Publications

Found 50493 results

Sort by: Author Title [ Type  (Asc)] Year
Journal Article
Rodineau P. "[Elementary respiratory care in the postoperative period]." Anesth Analg (Paris). 1978;35(4):677-84.
Betzhold J, Hong R. "Fatal graft-versus-host disease after a small leukocyte transfusion in a patient with lymphoma and varicella." Pediatrics. 1978;62(1):63-6. Abstract

A child with a poorly differentiated lymphoma developed varicella while being treated with maintenance chemotherapeutic agents. He received a transfusion of nonirradiated leukocytes from 1 unit of whole blood donated by a healthy volunteer who had recently recovered from varicella. The clinical course of varicella was aborted, but a classic graft-versus-host reaction developed and ultimately proved fatal. The host may have presented a large population of antigen-bearing cells to an infusion of presensitized immunocompetent donor cells, leading to an overwhelming aggressor lymphocyte reaction. We speculate that a modified approach using irradiated donor cells could be of benefit in the treatment of varicella infections in the immunosuppressed host.

Gatei DG, Odhiambo PA, Orinda DA, Muruka FJ, Wasunna A. "Retrospective study of carcinoma of the esophagus in Kenya." Cancer Res.. 1978;38(2):303-7. Abstract

A clinical, radiological, histological, and geographical study of carcinoma of the esophagus in Kenya is reported. It was found that this cancer is diagnosed more often in males than in females, with a ration of 8:1 (Kenya Cancer Registry). The most common age in males and females is 50 to 59 years. The regions of the esophagus most commonly involved are the middle and lower thirds, in almost equal proportions. An unexplained tendency for the tumor to be poorly differentiated towards the lower third is noted. In addition a review on the possible etiological factors is presented.

Calder JF, Wasunna AE. "Diverticular disease of the colon in Kenyan Africans." East Afr Med J. 1978;55(12):579-81.
Gripenberg U, Saarinen I, Bwibo NO, Oduori ML, Grayburn JA, Awori NW, Wasunna AE, Kinuthia DM. "Two true hermaphrodites with XX chromosomes." East Afr Med J. 1978;55(8):373-9.
Obel AO. "Antipyrine and progranolol disposition in malnutrition." East African Medical Journal. 1978;(55):20-24.
KAAYA, G.P., VALLI, V.E.O., MAXIE MG. "Bovine erythrocytic, granulocytic and macrophage colony formation in culture." Canadian Journal of Comparative Medicine. 1978;42:322-326.
Gichaga FJ. "Curriculum Development in Civil Engineering in Kenya." Journal, Institution of Engineers of Kenya.. 1978.
Mailu AM, Khamala CPM, Rose DJW. "Evaluation of pine woolly aphid damage to Pinus patula and its effect on yield in Kenya.". 1978. AbstractWebsite

It is reported in this further paper on the damage caused by Pineus pini (Gmel.) to Pinus patula in Kenya [see preceding abstract] that reduction in the elongation of the needles and stems occurs only after crown damage and aphid infestation become extreme. Lighter infestations are reflected in slight reductions of needle length. Damage to the trees and consequent losses of wood volume are most severe under warm dry conditions. Severely stunted needles caused by aphid feeding result in loss of half the tree yield. Infested stands may incur up to 5% economic loss in wood volume. These relations are, however, affected by site factors such as rainfall and altitude. With stands of P. patula at suitable sites. Pineus pini need not pose an important threat to plantations in Kenya.

Zuzarte JC;, Kasili EG. "Hepatitis B antigen--a review.". 1978.
Omondi LN, Odera LN. "Kenya's Independence.". 1978.Website
Kokwaro JO. "New Taxa and combination in Rutaceae of East Africa and North-East Africa." Kew Bulletin . 1978;34(4):785-798.
C.K. M. "Pharmacy – A profession with a crisis of identity." Kenya. Pharm J.. 1978;1(1):24.
Dr. Molepo PKDN. "Polymorphism of calcium carbonate." FC.D. 1978.
D.N. Kariuki and S.F.A. Kettle IC. "Raman Spectra of mixed crystals of transition metal hexacarbonyls.". 1978.
Gichaga FJ. "Research on Flexible Road Pavements in Kenya." Journal, Institution of Engineers of Kenya. . 1978:3-5.
Sketchley HR, Mbuvi JP, Scilley FM, Wokobi SM. "Soil science [in the Marginal Semi-Arid Lands of Kenya].". 1978.
Sketchley HR, Scilley FM, Wokobi SM. "Soil science [in the Marginal Semi-Arid Lands of Kenya].". 1978.Website
Khamala CPM, Okeyo-Owour JB. "Studies on insect podborer infestations on Cajanus cajan (L.) Millsp. (pigeon pea) under different insecticidal spraying regimes in the Kenya Highlands.". 1978. AbstractWebsite

Three insecticides were tested in sprays in the field in Kenya in 1976 for the control of podboring insects, especially the noctuids Pardasena virgulana (Mab.) and Heliothis armigera (Hb.) and the agromyzid Melanagromyza obtusa (Mall.), on pigeon pea (Cajanus cajan). DDT was applied twice at a concentration of 25% diluted to 180 ml/10 litres water, 40% dimethoate was applied at 30 ml/18 litres, and 35% endosulfan at 102 ml/18 litres water; these quantities were applied to 450 m2. The percentage pod damage and (in brackets) percentage seed damage totalled 30.4 (18.3) for DDT, 24.7 (13.5) for dimethoate, and 32.4 (17.3) for endosulfan, as compared with 47.9 (24.4) for no treatment.

C.K. 45. M. "Training of Pharmacists." Kenya J. Pharm.. 1978;1(1):19.
Mutiga ER. "Treatment of the repeat breeder cow syndrome in Kenya.". 1978. Abstract

One hundred repeat breeder dairy cows have been studied in detail. Although clinically 60 per cent of them were normal bacteria were isolated from the uteri of the majority (90 per cent). Thirty per cent of these isolates were mixed. Intra-uterine infusion of the uteri with diluted Lugol's Iodine solution, supplemented in a few cases by antibiotic therapy, resulted in a 62 per cent conception rate compared with 26 per cent in the control group. It is concluded that dilute Lugol's Iodine is a useful treatment for repeat breeder cows under conditions similar to those described.

Hardy DG, Rhoton Jr AL. "Microsurgical relationships of the superior cerebellar artery and the trigeminal nerve." Journal of neurosurgery. 1978;49:669-678. AbstractWebsite
n/a
McArdle CB, Dowling JE, Masland RH. "Development of outer segments and synapses in the rabbit retina." The Journal of Comparative Neurology. 1977;175:253-273. AbstractWebsite

The peripheral retina of rabbits aged 0 to 60 days was studied by electron microscopy. Ribbon and conventional synaptogenesis was studied with serial sections, and the density of synapses of the inner plexiform layer was measured on large (1,500μm2) montages. Photoreceptor and bipolar ribbon synapses seem to develop similarly in that processes of the prospective dyad or triad contact the presynaptic ribbon-containing terminal one at a time. No statistically significant difference in the lengths of ribbon lamellae was found at 11 and 30 days. Conventional synapses appear to result from the aggregation of synaptic vesicles on one side of junctions that first existed as symmetrical membrane densities without vesicles. The length of the synaptic membrane specialization remains constant between 0 and 30 days. The density of inner plexiform layer conventional synapses remains at a low and roughly constant level from 0 to 9 days, after which there is an abrupt increase to a plateau at about 20 days. After nine days the density of ribbon synapses also increases, with an initially steep time course similar to that of conventional synapses. All subcategories of synapse studied (amacrine-to-amacrine, amacrine-to-bipolar, serial, and reciprocal) participate in the general increase between 9 and 20 days. Functional circuits of the inner plexiform layer thus seem to be assembled primarily during the second and third weeks of life.

Fraley DS, Adler S. "Correction of hyperkalemia by bicarbonate despite constant blood {pH}." Kidney International. 1977;12:354-360. Abstract

Patients having hyperkalemia often are given bicarbonate to raise blood pH and shift extracellular potassium into cells. Blood pH in many hyperkalemic patients, however, is compensated. To determine whether bicarbonate, independent of its pH action, affects plasma potassium, 14 hyperkalemic patients were treated with bicarbonate in 5% dextrose. In five patients (changed pH group), blood pH rose at least 0.08, while in nine (constant pH group), it changed less than 0.04. In the first group, pH rose 0.12, bicarbonate rose 5.9 mEq/liter, and plasma potassium fell 1.6 mEq/liter, and plasma potassium fell 1.4 mEq/liter. The correlation between changes in plasma potassium and bicarbonate was identical in the two groups and independent of urinary potassium excretion. Four additional patients, who were treated with 5% dextrose alone, did not significantly lower their plasma potassium, although subsequent treatment with bicarbonate in 5% dextrose lowered their plasma potassium. Thus, bicarbonate lowers plasma potassium, independent of its effect on blood pH, and despite a risk of volume overload, should be used to treat hyperkalemia in compensated acid-base disorders, even in the presence of renal failure, provided the plasma bicarbonate concentration is decreased.

Saeki N, Rhoton AL. "Microsurgical anatomy of the upper basilar artery and the posterior circle of {Willis}." Journal of Neurosurgery. 1977;46:563-578. AbstractWebsite
n/a
Kreisberg RA. "Phosphorus deficiency and hypophosphatemia." Hospital Practice. 1977;12:121-128. Abstract

Low serum phosphorus levels, sometimes associated with depletion of phosphorus stores, can engender a variety of serious, often life-threatening physiologic changes. The proximate cause of this dangerous situation is usually medical intervention in such conditions as alcoholism and diabetic ketoacidosis, which can produce a shift of phosphorus within the body unless preventive measures are instituted.

Hickey TL, Spear PD, Kratz KE. "Quantitative studies of cell size in the cat's dorsal lateral geniculate nucleus following visual deprivation." The Journal of comparative neurology. 1977;172:265-281. Abstract

The effects of visual deprivation upon dorsal lateral geniculate (DLG) cell size were compared for seven kittens reared with monocular lid-suture (MD), seven with binocular lid-suture (BD), and six with one eye lid-sutured and the other eye enucleated soon after birth (MD-E). Six additional kittens were reared normally for comparison. For each kitten the cross-sectional areas of 300 cells were measured in one or both nuclei. Measurements were taken from the binocular segment of laminae A and A1 and the monocular segment of lamina A. In agreement with previous studies, cells in the binocular segment of the deprived laminae of MD cats were smaller (33-34%) than those in the non-deprived laminae. Comparisons with normal animals indicated that this difference was due to an increase (10-15%) in size of cells in the non-deprived laminae as well as a decrease (23-25%) in size of cells in the deprived laminae. Cells in the monocular segment also were affected by deprivation in MD cats, and this effect increased with the age (and duration of the deprivation) of the animal. However, it was always smaller than the decrease in cell size in the binocular portion of the DLG. In BD kittens, DLG cells were smaller (7-12%) than normal in all portions of the nucleus, including both the binocular and monocular segments. Direct comparisons between the deprived laminae of MD and BD kittens indicated that the decrease in cell size was greater for MD kittens in the binocular segment, but tended to be greater for BD kittens in the monocular segment. In MD-E kittens, DLG cells in the deprived laminae were smaller (11-17%) than normal in all portions of the nucleus, including both the binocular and monocular segments. Thus, the effects of deprivation were similar to those in BD kittens, even though inputs from the deprived eye had been placed at a competitive advantage in MD-E kittens. These results indicate that two factors may affect cell size in the DLG of visually deprived cats: deprivation per se and abnormal binocular competition. Finally, separate analyses for the ten largest and the ten smallest cells in each lamina of each cat were carried out in an attempt to determine if the changes in cell size were limited to the largest cells. In every case, differences observed for the total sample of cells were paralleled by differences from normal of both the largest cells present and the smallest cells present in the deprived laminae. Since at least two alternative interpretations can account for this finding, the question of whether the large cells are selectively affected by visual deprivation remains unanswered in the cat.

Von Noorden GK, Crawford MLJ, Middleditch PR. "Effect of lid suture on retinal ganglion cells {inMacaca} mulatta." Brain Research. 1977;122:437-444. AbstractWebsite

Previous work has established the pronounced effect of unilateral lid suture during visual immaturity on cell growth in the lateral geniculate nucleus of cats, dogs and monkeys. Most investigators have reported the retinas to be grossly normal but only a few quantitative studies are available and the results are contradictory. We have compared cell section diameters and cell density of parafoveal retinal ganglion cells in the deprived and non-deprived eye ofMacaca mulatta after the lids of one eye were sutured between the ages of 1–9 weeks for varying periods of time. The results show a decrease in the size and density of parafoveal retinal ganglion cells after long-term (24 months) visual deprivation. Lid suture of lesser duration (2–56 weeks) had no effect on the size of retinal ganglion cells.

Padilla AJ, Loeb JN. ""{Low}-dose" versus "high-dose" insulin regimens in the management of uncontrolled diabetes. {A} survey." The American Journal of Medicine. 1977;63:843-848. Abstract
n/a
Fisher JN, Shahshahani MN, Kitabchi AE. "Diabetic ketoacidosis: low-dose insulin therapy by various routes." The New England Journal of Medicine. 1977;297:238-241. Abstract

Since in normal persons the hypoglycemic effect of low-dose intramuscular exceeds that of subcutaneous insulin we studied the effect of routes of insulin therapy in diabetic ketoacidosis. Forty-five patients with diabetic ketoacidosis entered a randomized prospective protocol with insulin administered either intravenously, subcutaneously or intramuscularly. Initial priming dose of insulin had to be repeated in two of 15, three of 15 and six of 15 of the intravenous, subcutaneous and intramuscular groups respectively. The intravenous group had a more rapid fall in plasma glucose (P less than 0.01) and ketone bodies (P less than 0.05) during the first two hours. Thereafter, there were no significant differences in the rate of decline of plasma glucose or ketones nor in the time required for glucose to reach 250 mg per deciliter or for complete recovery from diabetic ketoacidosis. The data confirm the efficacy of low-dose insulin therapy for diabetic ketoacidosis and indicate that the optimal route of insulin administration is by initial intravenous combined with subcutaneous or intramuscular.

Terayama Y, Kaneko Y, Kawamoto K, Sakai N. "Ultrastructural changes of the nerve elements following disruption of the organ of {Corti}. {I}. {Nerve} elements in the organ of {Corti}." Acta oto-laryngologica. 1977;83:291-302. Abstract

3-137 days after disruption of the guinea pig organ of Corti by perilymphatic perfusion with 20% streptomycin (SM), ultrastructural changes of the nerve fibers in the organ were observed. Most of nerve fibers began to degenerate after a latent period of 4 days. On the other hand, a number of fibers survived reactively enlarged and later developed into myelinated and unmyelinated fibers by becoming enclosed in Schwann cells which entered the organ of Corti through the habenula perforata. Regeneration and sprouting of the surviving nerve fibers also occurred. The fibers became mature, but atrophied after 60 days and then gradually disappeared. The regenerating fibers were mainly of the myelinated and unmyelinated efferent type. Retrograde degeneration occurred in both afferent and efferent fibers. In the less damaged organ of Corti perfused with 2% SM or Ringer's solution, Schwann cell invasion was not found.

Okech MO, Orinda DA, Gatei DG, Wasunna AO. "Plasma oestradiol-17B and oestrogen receptors in mammary tumours among Africans." East Afr Med J. 1977;54(11):615-20.
Ostenson RC, Fields BT, Nolan CM. "Polymyxin B and rifampin: new regimen for multiresistant Serratia marcescens infections." Antimicrob. Agents Chemother.. 1977;12(6):655-9. Abstract

Polymyxin B and rifampin were given to 12 patients with multi-drug-resistant nosocomial Serratia marcescens infections. Eight cures were achieved; drug hepatotoxicity occurred once; one fatal suprainfection was encountered; and two patients died during therapy of causes related to severe underlying illnesses. Polymyxin B and rifampin were uniformly synergistic in vitro against the infecting strains and against 40 additional clinical isolates of S. marcescens.

Steel CM, Ennis M, Levin AG, Wasunna A. "The mitogenic response of cryopreserved human lymphocytes in a microculture system." Cytobios. 1977;18(70):89-99. Abstract

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

Maitai CK. "The toxicity of the plant Catha edulis in rats." Toxicon. 1977;15(4):363-6.
KAAYA, G.P. WINGVISTANDJOHNSONGLW. "Clinico-pathological aspects of Trypanosoma congolense infection in goats." Bulletin of animal Health and production in Africa. 1977;25:397-408.
Wanjala C. "Culture, the African Writer and Alienation." Maktaba: Official Journal of the Kenya Library Association. 1977;4(1):22-27.
J.S 1. N. "A Curriculum Development Programme in Physical Education." Plymouth Polytechnic. 1977;2(1):13-20.
Ogana W, Spreiter JR. "Derivation of an integral equation for transonic flows." AIAA Journal. 1977;Vol. 15(No. 2):pp. 281-282.
Ilnicki RD, Justin JR, Michieka RW. "The effects of some dinitroaniline herbicide on kenaf.". 1977.
Onyango OW. "Kenya's Water Problems.". 1977.Website
Mohamed PA,(ed) AIS. "Language Situation in Kenya." Languages et PolitiQues en Afrique Noire. 1977.
Ogana W. "Numerical solution for subcritical flows by a transonic integral equation method." AIAA Journal. 1977;Vol 15(No. 3):pp. 444-446.
Dossaji SF, Kairu MG, Gondwe AT, Ouma JH. "On the evaluation of the molluscicidal properties of Polygonum senegalense." Lloydia (J. of Nat. Prod.). 1977;40(3):290-293.
Okech MO, Orinda DA, Gatei DG, Wasunna AO. "Plasma oestradiol-17B and oestrogen receptors in mammary tumours among Africans.". 1977.
Michieka RW, Ilnicki RD, Justin JR, Zublena J. "Response of kenaf to some preemergence herbicides.". 1977.
and Kettle KDNSFA. ""The vibrational Spectra of mixed crystals of (C6H5)3PMxM1- x(CO)5, where M, M = Cr, Mo, W."." Journal of Raman Spectroscopy, 6, 319. 1977.
Wanjala C. "Theatre and Politics." African Perspectives. 1977;1(1):30-38.
OLIECH JS. "Thyrotoxicosis at Kenyatta National Hospital Nairobi.East Afr Med J. 1977 Oct;54(10):561-4." East Afr Med J. 1977 Oct;54(10):561-4.. 1977;vol. 54(10):561-564. Abstract

ABSTRAC
A three-year (1974-1977) retrospective study of 163 patients with goiter and signs of thyrotoxicosis was carried out.Of thesepatients, 65 (40%) had confirmed thyrotoxicosis,the rest were euthyroid.Kungu(1) reported 36 cases histologically diagnosed over a period of 5 years(1967-1971).Gitau in a six year study1968-1973) REPORTED 148 cases.This suggests that thyrotoxicosis is on the increase at KNH.One the reasons for the increase may be that the patients are becoming more aware of the disease and therefore reporting to the hospital for treatment.The second reason is that the doctors are increasingly interested in the disease.Thirdly, the introduction of iodised domestic salt may cause some patients to become toxic (iodine stimulation).The majority of patients were treated with antithyroid drugs;if they relapsed or did not respond to medical therpy, surgery or radio iodine were the next methods of treatment.

Burke LF, Clark E. "Ileocolic intussusception—a case report." Journal of Clinical Ultrasound. 1977;5:346-347. AbstractWebsite
n/a
Osborne DMP, Monaghan P. "Effects of light and dark upon photoreceptor synapses in the retina of {Xenopus} laevis." Cell and Tissue Research. 1976;173:211-220. AbstractWebsite

Photoreceptor synapses in Xenopus retina were studied after exposure to day/night cycles and continuous light or dark. In the rods, dense-core vesicles appear alongside the synaptic ribbons in animals exposed to light. In dark-adapted rods, electron-dense material is present in the synaptic clefts, but no dense-core vesicles are found associated with the synaptic ribbons. Cone photoreceptors do not show these ultrastructural changes in response to light and dark. Prolonged exposure to light (21 days) causes flattening of the synaptic vesicles associated with the synaptic ribbons in both rods and cones. The results are discussed in the light of what is known about transmitter release from photoreceptors.

Chernenko GA, West RW. "A re-examination of anatomical plasticity in the rat retina." The Journal of comparative neurology. 1976;167:49-62. Abstract

Previous investigators have reported an increase in numbers of amacrine synapses in the inner plexiform layer (IPL) of the rat retina following light deprivation, and an increase in amacrine along with a decrease in bipolar synapses following light damage. Since there are several points of disagreement between the published reports on this subject we undertook a more detailed study of the effects of light deprivation and light damage on the retina. Four groups of eight male albino rat pups (14 days old) were raised for eight weeks under different conditions: (1) unsutured, bright light reared (UB); (2) bilaterally lid-sutured, bright light reared (SB); (3) unsutured, low light reared (UL); and (4) bilaterally lid-sutured, dark reared (SD). The intensity of the light given the UL group was equated with that striking the corneas of the SB group. Light microscopy showed that the retinas of the SB as well as the UB groups had almost complete degeneration of the outer retinal layers, indicating that even low intensity light, when continuous, causes severe retinal damage. The SD group was thicker in many of the retinal layers compared to the UL (control) group. Electron microscopy revealed that there were no significant changes in the incidences of any type of synapse in the IPL following light deprivation or light damage when averaged over total depth. This is in contradiction to the reports of other investigators. However, when the IPL was analyzed by levels, the incidence of amacrine-ganglion synapses was signficantly greater (p less than 0.05) in groups UB and SD, but only in the outer third of the IPL. Thus, extensive postnatal plasticity of IPL synapses in the rat retina did not occur under our experimental conditions. We found, at best, only limited effects which were confined to the amacrine-ganglion synapses.

Kitabchi AE, Ayyagari V, Guerra SM. "The efficacy of low-dose versus conventional therapy of insulin for treatment of diabetic ketoacidosis." Annals of Internal Medicine. 1976;84:633-638. Abstract

The effect of low-dose intramuscular insulin therapy was compared with that of high-dose insulin therapy by intravenous and subcutaneous routes in 48 patients with diabetic ketoacidosis. A simplified protocol was devised to compare efficacy of the two methods of therapy in a randomized manner. Plasma glucose dropped to less than 250 mg/dl in the low-dose group in 6.7 +/- 0.8 h and in the high-dose group in 4.5 +/- 0.8 h (P = not significant). The amount of insulin necessary to lower plasma glucose to 250 mg/dl was 263 +/- 45 U in the high-dose group and 46 +/- 5 U in the low-dose group. Twenty five percent in the high-dose group and none in the low-dose group developed hypoglycemia. Other biochemical and clinical variables in the two groups were comparable. No treatment complications were noted in the low-dose group. Our studies suggest that low-dose intramuscular insulin therapy is simple and as effective as high-dose therapy in the treatment of diabetic ketoacidosis without the risk of hypoglycemia and with a diminished incidence of hypokalemia. Furthermore, the favorable response of these patients to low-dose insulin therapy suggests the absence of insulin resistance in diabetic ketoacidosis.

Maany I. "Tardive dyskinesia." Dis Nerv Syst. 1976;37(10):587.
Mosin VI, Radbil' OS. "[Cyclic nucleotides and intestinal function]." Klin Med (Mosk). 1976;54(10):23-8.
Berg CP, Rodden FA. "Purification of D-amino oxidase from Trigonopsis variabilis." Anal. Biochem.. 1976;71(1):214-22.
Holmgren JH. "Automated laundry increases productivity." Mod Healthc (Short Term Care). 1976;5(6):60.
Silverstein E, Friedland J, Lyons HA, Gourin A. "Markedly elevated angiotensin converting enzyme in lymph nodes containing non-necrotizing granulomas in sarcoidosis." Proc. Natl. Acad. Sci. U.S.A.. 1976;73(6):2137-41. Abstract

Sarcoidosis is a disease of unknown etiology that is characterized by the generalized formation of granulomas and is accompanied by elevation in the serum in less than half the patients of angiotensin converting enzyme, a dipeptidyl carboxypeptidase that catalyzes the conversion of the decapeptide, angiotensin I, to the pressor octapeptide, angiotensin II, and L-histidyl-L-leucine. Mean activity of angiotensin converting enzyme was elevated generally more than 10-fold in granuloma-containing lymph nodes, but not in lung in which normally it is abundant, in 19 of 20 patients with sarcoidosis. Angiotensin converting enzyme in lymph nodes from subjects with sarcoidosis was similar to the enzyme from normal lung and lymph node with respect to activity as a function of pH, inhibition of activity by EDTA and o-phenanthroline, gel filtration on Sephadex G-200, and requirement for chloride for activity, but appeared to be more heat labile. The data suggest that the granulomas in sarcoidosis may be the source of the elevated serum enzyme and that cells of the granulomas, particularly the epitheloid cells which appear by electron microscopy to have active protein biosynthesis, may be actively synthesizing the enzyme.

Roseleur OJ, van Gent CM. "Alkaline and enzymatic hydrolysis of conjugated bile acids." Clin. Chim. Acta. 1976;66(2):269-72.
Stamm O, Latscha U, Janecek P, Campana A. "Development of a special electrode for continuous subcutaneous pH measurement in the infant scalp." Am. J. Obstet. Gynecol.. 1976;124(2):193-5. Abstract

Using a combined special glass electrode it is possible to monitor pH ratios and pH variation in the subcutaneous tissue of the infant scalp continuously. Tests on a normal sample of newborn babies immediately after birth showed a significant correlation between tissue pH and capillary blood pH, with the trend of pH variation being broadly similar in both measurement media.

Stamm O, Latscha U, Janecek P, Campana A. "Development of a special electrode for continuous subcutaneous pH measurement in the infant scalp." Am. J. Obstet. Gynecol.. 1976;124(2):193-5. Abstract

Using a combined special glass electrode it is possible to monitor pH ratios and pH variation in the subcutaneous tissue of the infant scalp continuously. Tests on a normal sample of newborn babies immediately after birth showed a significant correlation between tissue pH and capillary blood pH, with the trend of pH variation being broadly similar in both measurement media.

Stamm O, Latscha U, Janecek P, Campana A. "Development of a special electrode for continuous subcutaneous pH measurement in the infant scalp." Am. J. Obstet. Gynecol.. 1976;124(2):193-5. Abstract

Using a combined special glass electrode it is possible to monitor pH ratios and pH variation in the subcutaneous tissue of the infant scalp continuously. Tests on a normal sample of newborn babies immediately after birth showed a significant correlation between tissue pH and capillary blood pH, with the trend of pH variation being broadly similar in both measurement media.

Raffle A, Gray J, MacDonald HR. "Letter: First-aid treatment of poisoning." Br Med J. 1976;1(6001):93.
O'Day DH. "Acid protease activity during germination of microcysts of the cellular slime mold Polysphondylium pallidum." J. Bacteriol.. 1976;125(1):8-13. Abstract

Extracts of dormant microcysts of Polysphondylium pallidum demonstrate pH optima for the hydrolysis of casein at 3.5 and 6.0. During germination the intracellular pH 6.0 caseinolytic specific activity does not change significantly. The pH 6.0 protease is also active on azo-albumin, revealing the same developmental pattern with this substrate. Both acid protease activities are excreted during the germination process. Addition of purified nonspecific protease to cultures speeds up germination, suggesting that the excreted protease may play a role in removal of the microcyst wall. When cycloheximide is added to cultures, complete germination (emergence) is stopped whereas the pH 6.0 protease activity still accumulates to between 50 and 60% of the maximum control activity. Although this suggests that post-translational controls might mediate the accumulation of a portion of the pH 6.0 protease increase, mixing and dilution experiments with cell extracts do not reveal the differential presence of soluble activators or inhibitors of this activity at different developmental stages. The presence of tightly bound enzyme-inhibitor complexes for protease B in dormant microcysts has not been ruled out and is currently under study.

Chern CJ, Beutler E. "Biochemical and electrophoretic studies of erythrocyte pyridoxine kinase in white and black Americans." Am. J. Hum. Genet.. 1976;28(1):9-17. Abstract

The mean PNK activity in red blood cells from black subjects was only about 40% of that in whites. Among 51 whites examined, one was found to have enzyme deficiency. The estimated gene frequencies for PNKH (the common allele in whites which codes for higher enzyme activity) and PNKL (the common allele in blacks which codes for lower enzyme activity) were .35 and .65, respectively, for black donors, and .81 and .19, respectively, for white donors, The variant enzyme in persons with enzyme deficiency was associated with an increased rate of degradation in red cells during aging. No other biochemical or electrophoretic differences were detected.

Chern CJ, Beutler E. "Biochemical and electrophoretic studies of erythrocyte pyridoxine kinase in white and black Americans." Am. J. Hum. Genet.. 1976;28(1):9-17. Abstract

The mean PNK activity in red blood cells from black subjects was only about 40% of that in whites. Among 51 whites examined, one was found to have enzyme deficiency. The estimated gene frequencies for PNKH (the common allele in whites which codes for higher enzyme activity) and PNKL (the common allele in blacks which codes for lower enzyme activity) were .35 and .65, respectively, for black donors, and .81 and .19, respectively, for white donors, The variant enzyme in persons with enzyme deficiency was associated with an increased rate of degradation in red cells during aging. No other biochemical or electrophoretic differences were detected.

Jacob JS, McDonald HS. "Diving bradycardia in four species of North American aquatic snakes." Comp Biochem Physiol A Comp Physiol. 1976;53(1):69-72.
Cochran DG. "Excreta analysis on additional cockroach species and the house cricket." Comp Biochem Physiol A Comp Physiol. 1976;53(1):79-81.
Belaich A, Belaich JP. "Microcalorimetric study of the anaerobic growth of Escherichia coli: growth thermograms in a synthetic medium." J. Bacteriol.. 1976;125(1):14-8. Abstract

A microcalorimetric technique was used for studying the growth of Escherichia coli during anaerobiosis. The growth thermograms obtained are complex and the shape of curves is dependent on the hydrogen lyase activity of the cells. Fermentation balances are given for different culture conditions, and simple growth thermograms are obtained when the hydrogen lyase activity is inhibitied.

Horty JF. "Negligence serves two masters." Mod Healthc (Short Term Care). 1976;5(1):58-60.
Share JB. "Review of drug treatment for Down's syndrome persons." Am J Ment Defic. 1976;80(4):388-93. Abstract

A review of drug treatment for Down's syndrome individuals was presented. Drugs used to modify behavior, as well as drugs used with the goal of affecting cognitive processes, were discussed. Some observations were offered as to the effectiveness of past and current drugs on Down's syndrome and some methodological problems relating to drug studies presented. There have not been any drugs that have demonstrated remarkable improvement in the status of Down's syndrome individuals that have been widely accepted as effective.

Share JB. "Review of drug treatment for Down's syndrome persons." Am J Ment Defic. 1976;80(4):388-93. Abstract

A review of drug treatment for Down's syndrome individuals was presented. Drugs used to modify behavior, as well as drugs used with the goal of affecting cognitive processes, were discussed. Some observations were offered as to the effectiveness of past and current drugs on Down's syndrome and some methodological problems relating to drug studies presented. There have not been any drugs that have demonstrated remarkable improvement in the status of Down's syndrome individuals that have been widely accepted as effective.

Bland RD, Clarke TL, Harden LB. "Rapid infusion of sodium bicarbonate and albumin into high-risk premature infants soon after birth: a controlled, prospective trial." Am. J. Obstet. Gynecol.. 1976;124(3):263-7. Abstract

We conducted a controlled, prospective trial to evaluate the effectiveness of rapidly infusing sodium bicarbonate (NaHCO3) and salt-poor albumin into high-risk, premature infants in the first 2 hours of life. Fifty-three infants, randomized into one of four treatment groups, received 8 ml. per kilogram of a solution containing either (A) glucose in water, (B) salt-poor albumin, (C) NaHCO3, or (D) a combination of albumin and NaHCO3. After the initial infusion, the babies received no colloid or alkali solutions until 4 hours of age. We managed them supportively with warmth, appropriate oxygen administration, isotonic fluid infusion, and close monitoring. Among the infants who received alkali, 14 of 26 acquired the respiratory distress syndrome (RDS), 11 died, and four had intracranial hemorrhage. Among babies who received no alkali, RDS occurred in 11 of 27, 5 died, and none had intracranial hemorrhage. These results do not support the common practice of rapidly infusing NaHCO3 into high-risk, premature infants, and they suggest that the early management of such infants needs renewed critical evaluation.

Bland RD, Clarke TL, Harden LB. "Rapid infusion of sodium bicarbonate and albumin into high-risk premature infants soon after birth: a controlled, prospective trial." Am. J. Obstet. Gynecol.. 1976;124(3):263-7. Abstract

We conducted a controlled, prospective trial to evaluate the effectiveness of rapidly infusing sodium bicarbonate (NaHCO3) and salt-poor albumin into high-risk, premature infants in the first 2 hours of life. Fifty-three infants, randomized into one of four treatment groups, received 8 ml. per kilogram of a solution containing either (A) glucose in water, (B) salt-poor albumin, (C) NaHCO3, or (D) a combination of albumin and NaHCO3. After the initial infusion, the babies received no colloid or alkali solutions until 4 hours of age. We managed them supportively with warmth, appropriate oxygen administration, isotonic fluid infusion, and close monitoring. Among the infants who received alkali, 14 of 26 acquired the respiratory distress syndrome (RDS), 11 died, and four had intracranial hemorrhage. Among babies who received no alkali, RDS occurred in 11 of 27, 5 died, and none had intracranial hemorrhage. These results do not support the common practice of rapidly infusing NaHCO3 into high-risk, premature infants, and they suggest that the early management of such infants needs renewed critical evaluation.

Bland RD, Clarke TL, Harden LB. "Rapid infusion of sodium bicarbonate and albumin into high-risk premature infants soon after birth: a controlled, prospective trial." Am. J. Obstet. Gynecol.. 1976;124(3):263-7. Abstract

We conducted a controlled, prospective trial to evaluate the effectiveness of rapidly infusing sodium bicarbonate (NaHCO3) and salt-poor albumin into high-risk, premature infants in the first 2 hours of life. Fifty-three infants, randomized into one of four treatment groups, received 8 ml. per kilogram of a solution containing either (A) glucose in water, (B) salt-poor albumin, (C) NaHCO3, or (D) a combination of albumin and NaHCO3. After the initial infusion, the babies received no colloid or alkali solutions until 4 hours of age. We managed them supportively with warmth, appropriate oxygen administration, isotonic fluid infusion, and close monitoring. Among the infants who received alkali, 14 of 26 acquired the respiratory distress syndrome (RDS), 11 died, and four had intracranial hemorrhage. Among babies who received no alkali, RDS occurred in 11 of 27, 5 died, and none had intracranial hemorrhage. These results do not support the common practice of rapidly infusing NaHCO3 into high-risk, premature infants, and they suggest that the early management of such infants needs renewed critical evaluation.

Fowler NO, McCall D, Chou TC, Holmes JC, Hanenson IB. "Electrocardiographic changes and cardiac arrhythmias in patients receiving psychotropic drugs." Am. J. Cardiol.. 1976;37(2):223-30. Abstract

Eight patients had cardiac manifestations that were life-threatening in five while taking psychotropic drugs, either phenothiazines or tricyclic antidepressants. Although most patients were receiving several drugs, Mellaril (thioridazine) appeared to be responsible for five cases of ventricular tachycardia, one of which was fatal in a 35 year old woman. Supraventricular tachycardia developed in one patient receiving Thorazine (chlorpromazine). Aventyl (nortriptyline) and Elavil (amitriptyline) each produced left bundle branch block in a 73 year old woman. Electrocardiographic T and U wave abnormalities were present in most patients. The ventricular arrhythmias responded to intravenous administration of lidocaine and to direct current electric shock; ventricular pacing was required in some instances and intravenous administration of propranolol combined with ventricular pacing in one. The tachyarrhythmias generally subsided within 48 hours after administration of the drugs was stopped. Five of the eight patients were 50 years of age or younger; only one clearly had antecedent heart disease. Major cardiac arrhythmias are a potential hazard in patients without heart disease who are receiving customary therapeutic doses of psychotropic drugs. A prospective clinical trial is suggested to quantify the risk of cardiac complications to patients receiving phenothiazines or tricyclic antidepressant drugs.

Zegers PV, Harmet KH, Hanzely L. "Inhibition of IAA-induced elongation in Avena coleoptile segments by lead: a physiological and an electron microscopic study." Cytobios. 1976;15(57):23-35. Abstract

A high resolution growth measuring apparatus was used to demonstrate the inhibition of auxin-induced cell elongation in oat coleoptile segments (Avena sativa L. var Holden) by lead at concentrations ranging from 2 x 10-6 M to 2 x 10-3 M. The inhibition was immediate, having no measurable lag period. Electron micrographs of lead-treated and control segments revealed that in the treated material, lead became localized as electron-dense granules in the cell walls and in vesicles associated with dictyosomes. These granules were found to be lead hydroxide phosphate by electron diffraction techniques. The possible significance of this localization and identification with regard to phosphatase activity is discussed.

Mayes KR, Holdich DM. "The water content of muscle and cuticle of the woodlouse Oniscus asellus in conditions of hydration and desiccation." Comp Biochem Physiol A Comp Physiol. 1976;53(3):253-8.
Kokwaro JO. "Euphorbiaceae.". 1976.Website
Brzustowski TA, Lutia MF. "Flow due to a two-dimensional heat source with cross flow in the atmosphere.". 1976. AbstractWebsite

This paper presents a model describing the flow field due to a two-dimensional infinitely long heat source in a stably-stratified atmosphere with a uniform wind cross-flow. The governing equation which is valid for any wind shear is non-linear in its general form and is solved for uniform flow only. The energy equation is not solved but a “source” function is assumed. The results of this model exhibit some of the observed mass fire characteristics such as the inflow window, the pinch effect, the upstream downdraft and a strong dynamic convection column. Blocking and the formation of eddies are shown to be the most important characteristics of the onset of mass fire conditions.

Mbaya VB. "Hepatic changes induced by Schrebera alata (Hochst): a preliminary report on the toxicology of II kau kawa.". 1976. Abstract

Schrebera alata is a deciduous fuel tree from which the Samburu people in Northern Kenya obtain bark for medicinal purposes. A pharmacologically active principle that produces analgesic effects can be extracted from the bark with hot water. When administered to rats daily for a period of 6 weeks, the extract of bark (referred to as II kau kawa by the Samburu) caused reduced activities of succinic dehydrogenase, an enzyme that is involved in oxidative processes, and cholinesterase in heart and liver tissues. Histological sections from the liver revealed extensive cellular degeneration and small areas with necrotic lesions. Only that fraction of the bark extracts which contained components less soluble in alcohol produced such lesions within a 2 weeks period. The same fraction is associated with pharmacological activity. Since hepatic injuries occur frequently and the incidence of primary hepatic carcinoma is high in tropical areas, the role of natural toxins as aetiologic factors for cirrhotic conditions must be adequately clarified. It is apparent that bark from S.alata possesses some toxicity and its effects on the liver indicate it can contribute significantly to prevalent hepatocellular damages.

Okwaro HW, Mbuvi JP, Sombroek WG. "Soils of semi-arid savanna zone of the north-eastern Kenya : site evaluation report.". 1976. Abstract

Recent ground observation and study of ERTS imagery, in connection with national programme for country-wide soils mapping at scale 1: 1,000,000, have yielded substantial new information on the nature and distribution of the soils in the savanna-covered semi-arid plains of the North-Eastern Kenya. The findings differ in several aspects from earlier schematic mapping, notably in the near absence of well-drained calcerous soils and the wide extent of saline/alkali soils in the central-eastern section. The origin of the different soils development at the various geomorphologic levels is discussed, in relation to the character of the sediments as well as the quaternary changes in climate. Also, an outline is given of the significance of such exploratory mapping, on physiographic basis, for the sound planning of range management, wildlife conservation and irrigation development in the area.

D.N. Kariuki and S.F.A. Kettle, & Ti Soi Sang. "Vibrational Spectra of molecular crystals of impure metal carbonyls".". 1976.
Rees BI, Lari J. "Chronic intussusception in children." British Journal of Surgery. 1976;63:33-35. AbstractWebsite
n/a
Hendrickson A, Boothe R. "Morphology of the retina and dorsal lateral geniculate nucleus in dark-reared monkeys ({Macaca} nemestrina)." Vision Research. 1976;16:517-IN5. AbstractWebsite

Nine infant monkeys were reared in continuous darkness from 2 weeks to 1, 3 and 6 months of age. One monkey was dark-reared from 3 to 7 months after birth. Light microscopic morphological studies of retina and dorsal lateral geniculate nucleus (dLGN) were done on animals sacrificed immediately after emerging from darkness and others that were tested behaviorally before sacrifice. Neither retina nor dLGN showed any obvious changes in cell number, size or staining characteristics when compared to light-reared, age-matched controls. Autoradiographic tracing of labeled retinal ganglion cell synaptic terminals indicated a normal distribution for dark-reared animals.

Gichaga FJ. "The Trans-African highway – Mombasa/Lagos,." Journal, Institution of Engineers of Kenya. 1975:16-21.
Powner D, Snyder JV, Grenvik A. "Altered pulmonary capillary permeability complicating recovery from diabetic ketoacidosis." Chest. 1975;68:253-256. Abstract

Self-limited noncardiogenic interstitial pulmonary edema probably reflecting altered permeability of the pulmonary capillary membrane is reported in a patient being treated for severe diabetic ketoacidosis. The possible etiology, associated findings, and therapy with continuous positive airway pressure (CPAP) by facemask are discussed.

LaVail MM, Battelle BA. "Influence of eye pigmentation and light deprivation on inherited retinal dystrophy in the rat." Experimental eye research. 1975;21:167-192. Abstract
n/a
Ostashevskiĭ II, Sungurov IA, Volchkov VA. "[Light scattering by cell suspensions in normal conditions and exposed to external factors]." Biofizika. 1975;20(5):853-8. Abstract

The characteristics of light scattering of cell suspensions in norm (pH 7,2, t=20degreesC) and upon external influences (change of pH and increase of tdegree). The turbidity tauapproximatelylambda-n and n=0,2--0,3 for cells in norm. After cell damage n increases. Dependence of n correlates with the increase of some injured cells determined by eozin test. Alterations of light scattering after cell damage were connected with the increase of deposit of intercellular structure in general scattering.

Akamatsu N, Nakajima H, Ono M, Miura Y. "Increase in acetyl CoA synthetase activity after phenobarbital treatment." Biochem. Pharmacol.. 1975;24(18):1725-7.
Bhagwat VM, Ramachandran BV. "Malathion A and B esterases of mouse liver-I." Biochem. Pharmacol.. 1975;24(18):1713-7.
Bhagwat VM, Ramachandran BV. "Malathion A and B esterases of mouse liver-I." Biochem. Pharmacol.. 1975;24(18):1713-7.
Bhagwat VM, Ramachandran BV. "Malathion A and B esterases of mouse liver-I." Biochem. Pharmacol.. 1975;24(18):1713-7.
Schmoldt A, Benthe HF, Haberland G. "Digitoxin metabolism by rat liver microsomes." Biochem. Pharmacol.. 1975;24(17):1639-41.
Schmoldt A, Benthe HF, Haberland G. "Digitoxin metabolism by rat liver microsomes." Biochem. Pharmacol.. 1975;24(17):1639-41.
Silen W, Machen TE, Forte JG. "Acid-base balance in amphibian gastric mucosa." Am. J. Physiol.. 1975;229(3):721-30. Abstract

It has been established that H+ secretion can be maintained in frog stomach in the absence of exogenous CO2 by using a nutrient bathing fluid containing 25 mM H2PO4 (pH approximately equal to 4.5) or by lowering the pH of a nonbuffered nutrient solution to about 3.0-3.6. Exogenous CO2 in the presence of these nutrient solutions uniformly caused a marked decrease in H+ secretion, PD, adn short-circuit current (Isc) and an increase in transmucosal resistance (R). Elevation of nutrient [k+] to 83 mM reduced R significantly but transiently without change in H+ when nutrient pH less than 5.0, whereas R returned to base line and H+ increased when nutrient pH greater than 5.0. Acidification of the nutrient medium in the presence of exogenous CO2 results in inhibition of the secretory pump, probably by decreasing intracellular pH, and also interferes with conductance at the nutrient membrane. Removal of exogenous CO2 from standard bicarbonate nutrient solution reduced by 50% the H+, PD, and Isc without change in R; K+-free nutrient solutions reverse these changes in Isc and PD but not in H+. The dropping PD and rising R induced by K+-free nutrient solutions in 5% CO2 - 95% O2 are returned toward normal by 100% O2. Our findings support an important role for exogenous CO2 in maintaining normal acid-base balance in frog mucosa by acting as an acidifying agent.

Flohr H, Breull W. "Effect of etafenone on total and regional myocardial blood flow." Arzneimittelforschung. 1975;25(9):1400-3. Abstract

The distribution of blood flow to the subendocardial, medium and subepicardial layers of the left ventricular free wall was studied in anaesthetized dogs under normoxic (A), hypoxic (B) conditions and under pharmacologically induced (etafenone) coronary vasodilation (C). Regional myocardial blood flow was determined by means of the particle distribution method. In normoxia a transmural gradient of flow was observed, with the subendocardial layers receiving a significantly higher flow rate compared with the subepicardial layers. In hypoxia induced vasodilation this transmural gradient of flow was persistent. In contrast a marked redistribution of regional flow was observed under pharmacologically induced vasodilation. The transmural gradient decreased. In contrast to some findings these experiments demonstrate that a considerable vasodilatory capacity exists in all layers of the myocardium and can be utilized by drugs. The differences observed for the intramural distribution pattern of flow under hypoxia and drug induced vasodilation support the hypothesis that this pattern reflects corresponding gradients of regional myocardial metabolism.

Thornton JA, Harrison MJ. "Letter: Duration of action of AH8165." Br J Anaesth. 1975;47(9):1033.
Coscia L, Causa P, Giuliani E, Nunziata A. "Pharmacological properties of new neuroleptic compounds." Arzneimittelforschung. 1975;25(9):1436-42. Abstract

RMI 61 140, RMI 61 144 and RMI 61 280 are newly synthetized N-[8-R-dibenzo(b,f)oxepin-10-yl]-N'-methyl-piperazine-maleates which show interesting psychopharmacologic effects. This work contains the results of a study performed with these three compounds, in order to demonstrate their neuropsycholeptic activity in comparison with chloropromazine (CPZ) and chlordiazepoxide (CPD). The inhibition of motility observed in mice shows that the compounds reduce the normal spontaneous motility as well as the muscle tone. The central-depressant activity is evidenced by increased barbiturate-induced sleep and a remarkable eyelid ptosis can also be observed. Our compounds do not show any activity on electroshock just as do CPZ and CPD. As to the antipsychotic outline, our compounds show strong reduction of lethality due to amphetamine in grouped mice and a strong antiapomorphine activity. They show also an antiaggressive effect and an inhibitory activity on avoidance behaviour much stronger than CPZ. We have also found extrapyramidal effects, as catalepsy, common to many tranquillizers of the kind of the standards used by us. As for vegetative phenomena, the compounds show hypotensive dose related action ranging from moderate to strong, probably due to an a-receptor inhibition. Adrenolytic activity against lethal doses of adrenaline, antiserotonin and antihistaminic effects, as well as other actions (hypothermia, analgesia, etc.) confirm that RMI 61 140, RMI 61 144 and RMI 61 280 are endowed with pharmacologic properties similar and more potent than those of CPZ. Studies on the metabolism of brain catecholamines show that they are similar to CPZ, although with less effect on dopamine level.

Coscia L, Causa P, Giuliani E, Nunziata A. "Pharmacological properties of new neuroleptic compounds." Arzneimittelforschung. 1975;25(9):1436-42. Abstract

RMI 61 140, RMI 61 144 and RMI 61 280 are newly synthetized N-[8-R-dibenzo(b,f)oxepin-10-yl]-N'-methyl-piperazine-maleates which show interesting psychopharmacologic effects. This work contains the results of a study performed with these three compounds, in order to demonstrate their neuropsycholeptic activity in comparison with chloropromazine (CPZ) and chlordiazepoxide (CPD). The inhibition of motility observed in mice shows that the compounds reduce the normal spontaneous motility as well as the muscle tone. The central-depressant activity is evidenced by increased barbiturate-induced sleep and a remarkable eyelid ptosis can also be observed. Our compounds do not show any activity on electroshock just as do CPZ and CPD. As to the antipsychotic outline, our compounds show strong reduction of lethality due to amphetamine in grouped mice and a strong antiapomorphine activity. They show also an antiaggressive effect and an inhibitory activity on avoidance behaviour much stronger than CPZ. We have also found extrapyramidal effects, as catalepsy, common to many tranquillizers of the kind of the standards used by us. As for vegetative phenomena, the compounds show hypotensive dose related action ranging from moderate to strong, probably due to an a-receptor inhibition. Adrenolytic activity against lethal doses of adrenaline, antiserotonin and antihistaminic effects, as well as other actions (hypothermia, analgesia, etc.) confirm that RMI 61 140, RMI 61 144 and RMI 61 280 are endowed with pharmacologic properties similar and more potent than those of CPZ. Studies on the metabolism of brain catecholamines show that they are similar to CPZ, although with less effect on dopamine level.

Scherberger RR, Kaess H, Brückner S. "[Studies on the action of an anticholinergic agent in combination with a tranquilizer on gastric juice secretion in man]." Arzneimittelforschung. 1975;25(9):1460-3. Abstract

A double-blind study with intra-individual comparisons was carried out to investigate the effects of 15 mg of (8r)-3alpha-hydroxy-8-isopropyl-1alphaH-tropanium bromide(+/-)-tropate (Sch 1000), 15 mg Sch 1000 + 10 mg oxazepam, 10 mg oxazepam and placebo with oral administration in randomized sequence on gastric juice volume, amount of acid, concentration and pH values in 12 healthy volunteers. The secretion parameters were measured during a 1-h basal period and a 2-h stimulation period. The gastric juice was obtained in 15 min portions via stomach tube. Stimulation was effected by 1 mug/kg/h pentagastrin via drip infusion. The Friedman test was used for the comparative statistical evaluation, and individual comparisons were carried out by means of the Wilcoxon test (pair-differences rank). The results show that Sch 1000 and Sch 1000 + oxazepam were equal in effect on basal and stimulated secretion volume. As compared with placebo, it was not possible to establish an effect on secretion volume for oxazepam alone. Sch 1000 and Sch 1000 + oxazepam were found to be equipotent in reducing the amount of basal acid, while oxazepam reduced this quantity only during the first 30 min of basal secretion. None of the three active preparations was capable of inhibiting the stimulated acid, although both Sch 1000 preparations produced a clear trend towards lowered mean values. During the basal secretion period, all three test preparations had an inhibiting action on acid concentration, but none of them had a significant effect during the stimulation period. The pH value was savely increased only by Sch 1000 and Sch 1000 + oxazepam, and this even only during the basal period. The results are discussed.

Hendrickson WA, Ward KB. "Atomic models for the polypeptide backbones of myohemerythrin and hemerythrin." Biochem. Biophys. Res. Commun.. 1975;66(4):1349-56.
Wiesmann UN, DiDonato S, Herschkowitz NN. "Effect of chloroquine on cultured fibroblasts: release of lysosomal hydrolases and inhibition of their uptake." Biochem. Biophys. Res. Commun.. 1975;66(4):1338-43.
Wiesmann UN, DiDonato S, Herschkowitz NN. "Effect of chloroquine on cultured fibroblasts: release of lysosomal hydrolases and inhibition of their uptake." Biochem. Biophys. Res. Commun.. 1975;66(4):1338-43.
Smith RJ, Bryant RG. "Metal substitutions incarbonic anhydrase: a halide ion probe study." Biochem. Biophys. Res. Commun.. 1975;66(4):1281-6.
Smith RJ, Bryant RG. "Metal substitutions incarbonic anhydrase: a halide ion probe study." Biochem. Biophys. Res. Commun.. 1975;66(4):1281-6.
Chow YW, Pietranico R, Mukerji A. "Studies of oxygen binding energy to hemoglobin molecule." Biochem. Biophys. Res. Commun.. 1975;66(4):1424-31.
Chow YW, Pietranico R, Mukerji A. "Studies of oxygen binding energy to hemoglobin molecule." Biochem. Biophys. Res. Commun.. 1975;66(4):1424-31.
Lorkin PA, Stephens AD, Beard ME, Wrigley PF, Adams L, Lehmann H. "Haemoglobin Rahere (beta Lys-Thr): A new high affinity haemoglobin associated with decreased 2, 3-diphosphoglycerate binding and relative polycythaemia." Br Med J. 1975;4(5990):200-2. Abstract

A new haemoglobin with increased oxygen affinity, beta82 (EF6) lysine leads to threonine (Hb Rahere), was found during the investigation of a patient who was found to have a raised haemoglobin concentration after a routine blood count. The substitution affects one of the 2, 3-diphosphoglycerate binding sites, resulting in an increased affinity for oxygen, but both the haem-haem interaction and the alkaline Bohr effect are normal in the haemolysate. This variant had the same mobility as haemoglobin A on electrophoresis at alkaline pH but was detected by measuring the whole blood oxygen affinity; it could be separated from haemoglobin A, however, by electrophoresis in agar at acid pH. The raised haemoglobin concentration was mainly due to a reduction in plasma volume (a relative polycythaemia) and was associated with a persistently raised white blood count. This case emphasises the need to measure the oxygen affinity of haemoglobin in all patients with absolute or relative polycythaemia when some obvious cause is not evident.

Barthel W, Markwardt F. "Aggregation of blood platelets by adrenaline and its uptake." Biochem. Pharmacol.. 1975;24(20):1903-4.
Ris MM, Deitrich RA, Von Wartburg JP. "Inhibition of aldehyde reductase isoenzymes in human and rat brain." Biochem. Pharmacol.. 1975;24(20):1865-9.
Theodor JL, Senelar R. "Cytotoxic interaction between gorgonian explants: mode of action." Cell. Immunol.. 1975;19(2):194-200.
Mier PD, van den Hurk JJ. "Lysosomal hydrolases of the epidermis. 2. Ester hydrolases." Br. J. Dermatol.. 1975;93(4):391-8. Abstract

Five distinct ester hydrolases (EC 3-1) have been characterized in guinea-pig epidermis. These are carboxylic esterase, acid phosphatase, pyrophosphatase, and arylsulphatase A and B. Their properties are consistent with those of lysosomal enzymes.

Nitta K, Yoneyama M. "Polymer concentration dependence of the helix to random coil transition of a charged polypeptide in aqueous salt solution." Biophys. Chem.. 1975;3(4):323-9. Abstract

The helix to coil transition of poly(L-glutamic acid) was investigated in 0.05 and 0.005 M aqueous potassium chloride solutions by use of potentiometric titration and circular dichroism measurement. Polymer concentration dependence of the transition was observed in the range from 0.006 to 0.04 monomol/e in 0.005 M KG1 solution. The polymer concentration dependence can be interpreted by current theories of the transition of charged polypeptides and of titration curves of linear weak polyelectrolytes taking the effect of polymer concentration into consideration.

Crow TJ, Deakin JF, Longden A. "Proceedings: Do anti-psychotic drugs act by dopamine receptor blockade in the nucleus accumbens." Br. J. Pharmacol.. 1975;55(2):295P-296P.
Miller FL, Cawley AJ, Choquette LP, Broughton E. "Radiographic examination of mandibular lesions in barren-ground caribou." J. Wildl. Dis.. 1975;11(4):465-70. Abstract

Dental anomalies were observed in 43 of 1,226 barren-ground caribou (Rangifer tarandus groenlandicus) taken between 1966 and 1968. In five of these 43 animals, the mandibles had deformities which radiography showed to be the result of dental abscesses in four cases and probably of a trauma in the other. The absence of actinomycotic lesions of the jaw bones of these 1,226 animals, and of more than 500 examined previously, indicates that "lumpy jaw" is rare in barren-ground caribou. The authors suggest the use of radiography to determine the nature of bone growth on skeletal remains, in the absence of soft tissues for examination for Actinomyces, either microscopically or by cultural methods.

Imamura K. "[Studies on the energy for sperm motility (author's transl)]." Nihon Funin Gakkai Zasshi. 1975;20(4):6-13.
Hunter AL, Klaassen CD. "Biliary excretion of colchicine in newborn rats." Drug Metab. Dispos.. 1975;3(6):530-5. Abstract

The 24-hr LD50 of colchicine in newborn rats is 0.24 mg/kg, which is about 1/10 that observed in the adult. The 24-hr LD50 of colchicine was relatively constant in rats over 25 days of age. In an attempt to determine the mechanism of the increased sensitivity of the newborn rat to the toxic action of colchicine, the distribution of 3H after the administration of 3H-colchicine (0.1 mg/kg) was measured in 10- and 35-day-old rats. The concentration of 3H was higher in all tissues of the newborn than the adult after ip administration, suggesting an immaturity in the pathway for colchicine elimination. After iv administration, radioactivity disappeared much more slowly from the plasma of the newborn rat than from the adult. This was due to a lower capacity of the liver of the newborn to concentrate colchicine and to excrete it into the bile. Development of the hepatic excretory mechanism responsible for excretion of colchicine occurred at the same age as did the increase in LD50. These results suggest that colchicine is more toxic in the newborn because the drug remains in the body for a longer time due to immaturity of the liver excretory process.

Weiss JM, Glazer HI, Pohorecky LA, Brick J, Miller NE. "Effects of chronic exposure to stressors on avoidance-escape behavior and on brain norepinephrine." Psychosom Med. 1975;37(6):522-34. Abstract

A single exposure to a severe stressor (either cold swim or inescapable shock) impairs subsequent performance in a shuttle avoidance-escape task (1), a deficit attributed to reduction in brain noradrenergic activity produced by these stressors. In the present paper, two experiments are described which examine how repeated exposure to such stressors affects (a) shuttle avoidance-escape performance (Experiment 1), and (b) aspects of brain norepinephrine metabolism (Experiment 2). Experiment 1 showed that, whereas subjects receiving the single exposure to cold swim or shock showed a large avoidance-escape deficit, subjects that received repeated exposure to these stressors for 14 days performed similarly to the control group that received no stressor. Experiment 2 showed that, whereas subjects that received one session of the inescapable shock stressor showed a lower level of norepinephrine in hypothalamus and cortex than did subjects that received no shock, subjects that received repeated exposure to inescapable shock or cold swim showed neurochemical "habituation." Subjects that received repeated shock showed elevated tyrosine hydroxylase activity and no depletion of norepinephrine level, and both repeated shock and cold swim caused a decrease in uptake of 3H-norepinephrine by slices of cortex in vitro. Thus, it is concluded that the behavioral and neurochemical changes that were observed after the stressful conditions studied are consistent with the hypothesis that changes in avoidance-escape responding following exposure to these stressful events are due to changes in brain noradrenergic activity.

Galliard T, Phillips DR, Matthew JA. "Enzymic reactions of fatty acid hydroperoxides in extracts of potato tuber. II. Conversion of 9- and 13-hydroperoxy-octadecadienoic acids to monohydroxydienoic acid, epoxyhydroxy- and trihydroxymonoenoic acid derivatives." Biochim. Biophys. Acta. 1975;409(2):157-71. Abstract

1. Crude extracts and partially purified enzyme preparations from potato tubers catalyse, at pH 5-7, the conversion of linoleic acid hydroperoxides to a range of oxygenated fatty acid derivatives. 2. 9-D- and 13-L-hydroperoxide isomers are converted at similar rates to equivalent (isomeric) products. 3. The major products from the 13-hydroperoxide isomer were identified as the corresponding monohydroxydienoic acid derivative, threo-11-hydroxy-trans12,13-epoxy-octadec-cis9-enoic acid and 9,12,13-trihydroxy-octadec-trans10-enoic acid. The corresponding products from the 9-hydroperoxide were the monohydroxydienoic acid, 9,10-epoxy-11-hydroxy-octadec-12-enoic acid and 9,10,13-trihydroxy-octadec-11-enoic acid. 4. No separation of activities forming the different products was achieved by partial purification of enzyme extracts. 5. Product formation was unaffected by EDTA, CN-, sulphydryl reagents or glutathione but was reduced by boiling the extracts. 6. This system is compared with the 9-hydroperoxide-specific enzymic formation of divinyl ether derivatives by potato extracts.

Wan H, Horvath C. "Behavior of soluble and immobilized acid phosphatase in hydro-organic media." Biochim. Biophys. Acta. 1975;410(1):135-44. Abstract

The hydrolysis of p-nitrophenyl phosphate by wheat germ acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) has been investigated in mixtures of aqueous buffers with acetone, dioxane and acetonitrile. The enzyme was either in free solution or immobilized on a pellicular support which consisted of a porous carbonaceous layer on solid glass beads. The highest enzyme activity was obtained in acetone and acetonitrile mixed with citrate buffer over a wide range of organic solvent concentration. In 50% (v/v) acetone both V and Km of the immobilized enzyme were about half of the values in the neat aqueous buffer, but the Ki for inorganic phosphate was unchanged. In 50% (v/v) mixtures of various solvents and citrate buffers of different pH, the enzymic activity was found to depend on the pH of the aqueous buffer component rather than the pH of the hydro-organic mixture as measured with the glass-calomel electrode. The relatively high rates of p-nitrophenol liberation in the presence of glucose even at high organic solvent concentrations suggest that transphosphorylation is facilitated at low water activity.

Yoshimura F, Suzuki T. "Calcium-stimulated adenosine triphosphatase in the microsomal fraction of tooth germ from porcine fetus." Biochim. Biophys. Acta. 1975;410(1):167-77. Abstract

The characterization and localization of a Ca(2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) in the tooth germ of the porcine fetus are reported. This enzyme, a microsome fraction, is preferentially activated by Ca(2+). In the presence of 0.5 mM ATP, maximal enzyme activity is obtained at 0.5--1.0 mM CaCl2. The maximal rate of ATP hydrolysis is approx. 20 mumol per h per mg of protein as the enzyme preparation is used here. At optimal Ca(2+) concentration, the Mg(2+) has an inhibitory effect. The enzyme does not require Na+ or/and K+ for activation by Ca(2+). Other nucleotide triphosphates may serve as the substrate, but V for ATP is the highest. The Km for ATP is 8.85 - 10(-5) M. The optimal pH for Ca(2+) activation of the enzyme lies around 9.2. Well known inhibitors of (Na+ + K+)-ATPase, mitochondria ATPase and Ca(2+)-ATPase in the erthrocyte do not inhibit the enzyme. In the subcellular order the enzyme may be assumed to be localized in the smooth endoplasmic reticulum fraction containing cell and Golgi body membrane fragments and in the tissue order in the enamel organ containing an ameloblast layer, stratum intermedium and stellate reticulum.

Tan AW, Nuttall FQ. "Characteristics of the dephosphorylated form of phosphorylase purified from rat liver and measurement of its activity in crude liver preparations." Biochim. Biophys. Acta. 1975;410(1):45-60. Abstract

The phosphorylated form of liver glycogen phosphorylase (alpha-1,4-glucan : orthophosphate alpha-glucosyl-transferase, EC 2.4.1.1) (phosphorylase a) is active and easily measured while the dephosphorylated form (phosphorylase b), in contrast to the muscle enzyme, has been reported to be essentially inactive even in the presence of AMP. We have purified both forms of phosphorylase from rat liver and studied the characteristics of each. Phosphorylase b activity can be measured with our assay conditions. The phosphorylase b we obtained was stimulated by high concentrations of sulfate, and was a substrate for muscle phosphorylase kinase whereas phosphorylase a was inhibited by sulfate, and was a substrate for liver phosphorylase phosphatase. Substrate binding to phosphorylase b was poor (KM glycogen = 2.5 mM, glucose-1-P = 250 mM) compared to phosphorylase a (KM glycogen = 1.8 mM, KM glucose-1-P = 0.7 mM). Liver phosphorylase b was active in the absence of AMP. However, AMP lowered the KM for glucose-1-P to 80 mM for purified phosphorylase b and to 60 mM for the enzyme in crude extract (Ka = 0.5 mM). Using appropriate substrate, buffer and AMP concentrations, assay conditions have been developed which allow determination of phosphorylase a and 90% of the phosphorylase b activity in liver extracts. Interconversion of the two forms can be demonstrated in vivo (under acute stimulation) and in vitro with little change in total activity. A decrease in total phosphorylase activity has been observed after prolonged starvation and in diabetes.

Fluck RA, Jaffe MJ. "Cholinesterases from plant tissues. VI. Preliminary characterization of enzymes from Solanum melongena L. and Zea mays L." Biochim. Biophys. Acta. 1975;410(1):130-4. Abstract

Enzymes capable of hydrolyzing esters of thiocholine have been assayed in extracts of Solanum melongena L. (eggplant) and Zea Mays L. (corn). The enzymes from both species are inhibited by the anti-cholinesterases neostigmine, physostigmine, and 284c51 and by AMO-1618, a plant growth retardant and they both have pH optima near pH 8.0. The enzyme from eggplant is maximally active at a substrate concentration of 0.15 mM acetylthiocholine and is inhibited at higher substrate concentrations. On the basis of this last property, the magnitude of inhibition by the various inhibitors, and the substrate specificity, we conclude that the enzyme from eggplant, but not that from corn, is a cholinesterase.

Chegwidden WR, Watts DC. "Kinetic studies and effects of anions on creatine phosphokinase from skeletal muscle of rhesus monkey (Macaca mulatta)." Biochim. Biophys. Acta. 1975;410(1):99-114. Abstract

A purification procedure for creatine kinase (EC 2.7.3.2) from muscle of the monke35--170 muequiv H+/mg protein per min at 30 degrees C and a yield of approx. 0.5 g/kg muscle. Assuming equilibrium kinetics, synergistic binding of substrates at one catalytic site is found for both the forward and back reactions. Kinetic constants for the binding of each substrate to the free enzyme and the enzyme-second substrate complex are determined and are compared with those for the enzyme from other species. Inhibition by small anions is determined in the presence of different combinations of substrates and products. SO4(2-) inhibits by simple competitive inhibition and probably binds at the site of the transferrable phosphoryl group. Inhibition by NO3-, NO2-, SCN- and Cl- is more complex and these ions are suggested to mimic the transferrable phosphoryl group in a planar transition-state complex. These anions stabilize the dead-end complex, enzyme-creatine-MgADP, which lacks the transferable phosphoryl group. The effects of these anions on the dissociation constants of the enzyme-substrate complexes is reported and is in accord with the above hypothesis. The dead-end complex in the absence of anion does not protect the essential thiol group against inhibition by iodoacetamide. Addition of NO3- or Cl- to the dead-end complex or a substrate equilibrium mixture without anion confers protection. The essential thiol group is inhibited by iodoacetamide at a rate which is essentially independent of pH over the normal stability range of the enzyme. Contrary to our previous report this pH independence is not altered by the presence of dead-end complex, creatine plus MgADP, in the presence or absence of anion or in the presence of a substrate equilibrium mixture. It is inferred that the 'essential' thiol group of the monkey enzyme has essentially the same properties as that of the rabbit enzyme. In consequence, the inferences made about the role of this group based on our previous work on the monkey enzyme are no longer valid. The present findings are compatible with the essential thiol group playing a conformational role in the catalytic process.

Kumar R, Tao M. "Multiple forms of casein kinase from rabbit erythrocytes." Biochim. Biophys. Acta. 1975;410(1):87-98. Abstract

Two rabbit erythrocyte casein kinases, GTP:casein kinase I and GTP:casein kinase II, have been purified 29 000- and 47 000-fold, respectively. Studies employing sucrose density gradient centrifugation indicate that kinase I has a molecular weight of about 9.5 - 10(5) (25 S) and kinase II about 1.4 - 10(6) (32 S). These enzymes can utilize either ATP or GTP as the phosphoryl donor. Among various protein substrates examined, these kinases catalyze the phosphorylation of casein greater than 50% dephosphorylated phosvitin congruent to 50% dephosphorylated casein greater than phosvitin. Histones, protamine and bovine serum albumin are poor phosphoryl acceptors. Kinetic data indicate that both enzymes are inhibited by high casein substrate concentrations which may be partially relieved by NaCl. Both phosphotransferases require Mg(2+) for activity and are optimally active at pH 9.0. The enzymes have apparent Km values of 2.5 - 10(-5) M for GTP, 2 - 10(-5) M for ATP, and 0.4--0.6 mg/ml for casein. The incorporation of the terminal phosphate of GTP into casein as catalyzed by these enzymes is inhibited to varying degrees by ATP, ITP, ADP, and GDP but not by UTP, CTP, GMP, adenosine 3':5'-cyclic monophosphate, and guanosine 3':5'-cyclic monophosphate. In addition, NaF and 2,3-diphosphoglyceric acid are also found to inhibit the activity of both kinases. The effect of 2,3-diphosphoglycerate is interesting and suggests that this metabolite may regulate the activity of the casein kinases in the red blood cells.

Kumar R, Tao M. "Multiple forms of casein kinase from rabbit erythrocytes." Biochim. Biophys. Acta. 1975;410(1):87-98. Abstract

Two rabbit erythrocyte casein kinases, GTP:casein kinase I and GTP:casein kinase II, have been purified 29 000- and 47 000-fold, respectively. Studies employing sucrose density gradient centrifugation indicate that kinase I has a molecular weight of about 9.5 - 10(5) (25 S) and kinase II about 1.4 - 10(6) (32 S). These enzymes can utilize either ATP or GTP as the phosphoryl donor. Among various protein substrates examined, these kinases catalyze the phosphorylation of casein greater than 50% dephosphorylated phosvitin congruent to 50% dephosphorylated casein greater than phosvitin. Histones, protamine and bovine serum albumin are poor phosphoryl acceptors. Kinetic data indicate that both enzymes are inhibited by high casein substrate concentrations which may be partially relieved by NaCl. Both phosphotransferases require Mg(2+) for activity and are optimally active at pH 9.0. The enzymes have apparent Km values of 2.5 - 10(-5) M for GTP, 2 - 10(-5) M for ATP, and 0.4--0.6 mg/ml for casein. The incorporation of the terminal phosphate of GTP into casein as catalyzed by these enzymes is inhibited to varying degrees by ATP, ITP, ADP, and GDP but not by UTP, CTP, GMP, adenosine 3':5'-cyclic monophosphate, and guanosine 3':5'-cyclic monophosphate. In addition, NaF and 2,3-diphosphoglyceric acid are also found to inhibit the activity of both kinases. The effect of 2,3-diphosphoglycerate is interesting and suggests that this metabolite may regulate the activity of the casein kinases in the red blood cells.

Elgart ES, Gusovsky T, Rosenberg MD. "Preparation and characterization of an enzymatically active immobilized derivative of myosin." Biochim. Biophys. Acta. 1975;410(1):178-92. Abstract

Purified skeletal muscle myosin (EC 3.6.1.3) has been covalently bound to Sepharose 4B by the cyanogen bromide procedure. The resulting complex, Sepharose-Myosin, possesses adenosine triphosphatase activity and is relatively stable for long periods of time. Under optimal binding conditions, approximately 33% of the specific ATPase activity of the bound myosin is retained. Polyacrylamide gel electrophoresis of polypeptides released from denatured Sepharose-Myosin indicates that 85% of the myosin is attached to the agarose beads through the heavy chains and the remainder through the light chains, in agreement with predictions of binding and release based upon either the lysine contents or molecular weights of themyosin subunits. The adenosine triphosphatase of the immobilized myosin has been investigated under conditions of varying pH, ionic strength, and cation concentration. The ATPase profiles of immobilized myosin are quite similar to those for free myosin, however subtle differences are found. The Sepharose-Myosin ATPase is not as sensitive as myosin to alterations in salt concentration and the apparent KM is approximately two-fold higher than that of myosin. These differences are probably due to chemical modification in the region of the attachment site(s) to the agarose beads and hydration and diffusion limitations imposed by the polymeric agarose matrix.

Tominaga Y, Tsujisaka Y. "Purification and some enzymatic properties of the chitosanase from Bacillus R-4 which lyses Rhizopus cell walls." Biochim. Biophys. Acta. 1975;410(1):145-55. Abstract

A strain of Bacillus sp (Bacillus R-4) produces a protease and a carbohydrolase both of which have the ability to lyse Rhizopus cell walls. Of the enzymes, the carbohydrolase has been purified to an ultracentrifugally and electrophoretically homogeneous state, and identified as a chitosanase. The enzyme was active on glycol chitosan as well as chitosan. Molecular weight of the purified enzyme was estimated as 31 000 and isoelectric point as pH 8.30. The enzyme was most active at pH 5.6 and at 40 degrees C with either Rhizopus cell wall or glycol chitosan as substrate, and was stable over a range of pH 4.5 to 7.5 at 40 degrees C for 3 h. The activity was lost by sulfhydryl reagents and restored by either reduced glutathione of L-cysteine. An abrupt decrease in viscosity of the reaction mixture suggested an endowise cleavage of chitosan by this enzyme.

Moroff G, Brandt KG. "Yeast glutathione reductase. Studies of the kinetics and stability of the enzyme as a function of pH and salt concentration." Biochim. Biophys. Acta. 1975;410(1):21-31. Abstract

1. The pH dependencies of the apparent Michaelis constant for oxidized glutathione and the apparent turnover number of yeast glutathione reductase (EC 1.6.4.2) have been determined at a fixed concentration of 0.1 mM NADPH in the range pH 4.5--8.0. Between pH 5.5 and 7.6, both of these parameters are relatively constant. The principal effect of low pH on the kinetics of the enzyme-catalyzed reaction is the observation of a pH-dependent substrate inhibition by oxidized glutathione at pH less than or equal 7, which is shown to correlate with the binding of oxidized glutathione to the oxidized form of the enzyme. 2. The catalytic activity of yeast glutathione reductase at pH 5.5 is affected by the sodium acetate buffer concentration. The stability of the oxidized and reduced forms of the enzyme at pH 5.5 and 25 degrees C in the absence of bovine serum albumin was studied as a function of sodium acetate concentration. The results show that activation of the catalytic activity of the enzyme at low sodium acetate concentration correlates with an effect of sodium acetate on a reduced form of the enzyme. In contrast, inhibition of the catalytic activity of the enzyme at high sodium acetate concentration correlates with an effect of sodium acetate on the oxidized form of the enzyme.

Moroff G, Brandt KG. "Yeast glutathione reductase. Studies of the kinetics and stability of the enzyme as a function of pH and salt concentration." Biochim. Biophys. Acta. 1975;410(1):21-31. Abstract

1. The pH dependencies of the apparent Michaelis constant for oxidized glutathione and the apparent turnover number of yeast glutathione reductase (EC 1.6.4.2) have been determined at a fixed concentration of 0.1 mM NADPH in the range pH 4.5--8.0. Between pH 5.5 and 7.6, both of these parameters are relatively constant. The principal effect of low pH on the kinetics of the enzyme-catalyzed reaction is the observation of a pH-dependent substrate inhibition by oxidized glutathione at pH less than or equal 7, which is shown to correlate with the binding of oxidized glutathione to the oxidized form of the enzyme. 2. The catalytic activity of yeast glutathione reductase at pH 5.5 is affected by the sodium acetate buffer concentration. The stability of the oxidized and reduced forms of the enzyme at pH 5.5 and 25 degrees C in the absence of bovine serum albumin was studied as a function of sodium acetate concentration. The results show that activation of the catalytic activity of the enzyme at low sodium acetate concentration correlates with an effect of sodium acetate on a reduced form of the enzyme. In contrast, inhibition of the catalytic activity of the enzyme at high sodium acetate concentration correlates with an effect of sodium acetate on the oxidized form of the enzyme.

UoN Websites Search