Bio

Publications


2010

Yuko-Jowi, C, Mukhwana R, Onyango FE.  2010.  Multifocal pheochromocytoma in early childhood: case report., 2010 Jun. East African medical journal. 87(6):269-72. Abstract

A three and a half year old male with multifocal phaeochromocytoma involving the right adrenal gland and an intrathoracic mass is presented. Twenty four hour vanillylmandelic acid (VMA) was negative despite suggestive symptomatology. The diagnosis was made on serial CT scans of the head, thoracic inlet and pelvis. He underwent right adrenalectomy and thoracotomy to remove the abdominal and intrathoracic mass. The diagnosis was confirmed by histology. He remained hypertensive on hefty antihypertensive doses throughout his lifespan and finally succumbed to status epilepticus at the age of ten, six years from the time of diagnosis.

Nzou, C, Kambarami RA, Onyango FE, Ndhlovu CE, Chikwasha V.  2010.  Clinical predictors of low CD4 count among HIV infected pulmonary tuberculosis clients: a health facility-based survey., 2010 Sep. South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde. 100(9):602-5. Abstract

The study aimed to determine the clinical and laboratory predictors of a low CD4+ cell count (<200 cells/microl) in HIV-infected patients with pulmonary tuberculosis (PTB).

2004

2001

Nduati, R, Richardson BA, John G, Mbori-Ngacha D, Mwatha A, Ndinya-Achola J, Bwayo J, Onyango FE, Kreiss J.  2001.  Effect of breastfeeding on mortality among HIV-1 infected women: a randomised trial., 2001 May 26. Lancet. 357(9269):1651-5. Abstract

We have completed a randomised clinical trial of breastfeeding and formula feeding to identify the frequency of breastmilk transmission of HIV-1 to infants. However, we also analysed data from this trial to examine the effect of breastfeeding on maternal death rates during 2 years after delivery. We report our findings from this secondary analysis.

2000

Nduati, R, John G, Mbori-Ngacha D, Richardson B, Overbaugh J, Mwatha A, Ndinya-Achola J, Bwayo J, Onyango FE, Hughes J, Kreiss J.  2000.  Effect of breastfeeding and formula feeding on transmission of HIV-1: a randomized clinical trial., 2000 Mar 1. JAMA : the journal of the American Medical Association. 283(9):1167-74. Abstract

Transmission of human immunodeficiency virus type 1 (HIV-1) is known to occur through breastfeeding, but the magnitude of risk has not been precisely defined. Whether breast milk HIV-1 transmission risk exceeds the potential risk of formula-associated diarrheal mortality in developing countries is unknown.

1999

Wafula, EM, Limbe MS, Onyango FE, Nduati R.  1999.  Effects of passive smoking and breastfeeding on childhood bronchial asthma., 1999 Nov. East African medical journal. 76(11):606-9. Abstract

To evaluate the effect of passive smoking and breastfeeding on the severity and age of onset of bronchial asthma.

1998

Wafula, EM, Ngamau DW, Onyango FE, Mirza NM, Njeru EK.  1998.  X-ray diagnosable pneumonia in children with severe malnutrition at Kenyatta National Hospital., 1998 Oct. East African medical journal. 75(10):567-71. Abstract

To estimate the prevalence of radiologically evident pneumonia among children with severe malnutrition and to evaluate the diagnostic utility of commonly used clinical indicators of pneumonia among children with severe malnutrition.

1995

Mbori-Ngacha, DA, Otieno JA, Njeru EK, Onyango FE.  1995.  Prevalence of persistent diarrhoea in children aged 3-36 months at the Kenyatta National Hospital, Nairobi, Kenya., 1995 Nov. East African medical journal. 72(11):711-4. Abstract

Three hundred and eighty four children aged 3-36 months admitted to the Infectious Diseases Hospital (IDH) with diarrhoea were studied for persistent diarrhoea (PD), defined as diarrhoea lasting more than 14 days. To establish the duration of diarrhoea, the children were evaluated daily while in hospital and on days seven, fourteen, twenty one and twenty eight of the diarrhoea episode, if discharged. Of these children, 268 (69.8%) were less than 12 months. There was a slight male preponderance with a male to female ratio of 1.2:1. Twenty (5.4%) children presented with diarrhoea of more than 14 days at admission while of the 364 who presented with diarrhoea of less than 14 days at admission, 40 (11%) developed persistent diarrhoea, giving a total PD rate of 16.5%. The peak age for PD was nine months with no sex difference. Some possible risk factors for PD were identified as blood in stools, pneumonia, malnutrition, not breastfeeding, severe dehydration and antibiotic treatment. The total number of deaths in the study cases was 50, giving a case fatality rate of 13.6%. Of the children with PD, 19(31.7%) died. The children with PD were at a four times greater risk of dying (P<0.001, OR = 4.16). This study indicates that prevalence of PD among children admitted to IDH is high; and carries a high case fatality.

Mbori-Ngacha, DA, Onyango FE, Chunge C, Luta M, Oloo AJ, Muga RO.  1995.  Efficacy of halofantrine in the treatment of uncomplicated falciparum malaria., 1995 Dec. East African medical journal. 72(12):796-9. Abstract

In the last decade, Plasmodium falciparum resistance to a number of commonly used anti-malarials especially chloroquine, has increased considerably. Newer anti-malarial drugs are therefore being aggressively evaluated as alternatives. A randomized double-blind controlled trial was therefore undertaken, to compare the efficacy of halofantrine to that of metakelfin, in the treatment of moderately severe infections of Plasmodium falciparum in an endemic malaria area in Kenya. Three hundred and thirty five subjects with laboratory confirmed malaria were recruited and randomized to receive treatment with either halofantrine (171 subjects) or metakelfin (164 subjects). Two thirds (66%) of the study subjects were under the age of five years, and were therefore considered to have minimal immunity. All study subjects were initially admitted to hospital for three days and then followed up as out-patients on days 7, 14, 21, and 28. The level of parasitaemia, the presence of fever and the occurrence of adverse effects were evaluated. Halofantrine was found to be comparable to metakelfin in terms of resolution of fever (mean time 45 and 51 hours respectively). No major adverse side effects were observed. Halofantrine is a viable drug in the treatment of uncomplicated P. falciparum malaria.

1994

Stanek, EJ, Wafula EM, Onyango FE, Musia J.  1994.  Characteristics related to the incidence and prevalence of acute respiratory tract infection in young children in Kenya., 1994 Apr. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 18(4):639-47. Abstract

Acute respiratory tract infection (ARI) in children is a prevalent condition that results in substantial morbidity and consumes large portions of health care resources in developing countries. We examined factors associated with the reported incidence and prevalence of ARI in a 3-year longitudinal study of 485 children < 5 years of age in rural Kenya. A large number of environmental factors, household and family characteristics, and child-specific factors were examined with use of multivariable methods. Few variables that may play a role in the incidence and prevalence of ARI (e.g., household tobacco use and weight z-score) were found to be related to such rates. Several factors related to ARI incidence and prevalence (e.g., mother's age, number of children, and community) were found to be associated with only mild ARI episodes. Evidence is presented to support the hypothesis that these factors are related to differential reporting of mild ARI episodes. The impact of such differential reporting on health care utilization and health education is discussed.

1993

Wamola, IA, Mirza NB, Ombette JJ, Onyango FE.  1993.  Recent epidemic meningococcal meningitis in Nairobi. Abstract

This is a prospective study of the recent explosive epidemic of group A meningococcal meningitis that occurred in Nairobi from April 1989 to January 1990. It was compared with previous less explosive outbreaks that occurred from 1975 to 1981. The recent epidemic was correlated to its Neisseria meningiriais carrier status among case-control samples with carrier rate in nasopharyngeal respiratory pathogens of children born of human immunodeficiency virus (HIV-1) positive and negative mothers at about the same time of the outbreak. The effect of mass vaccination on the course of the outbreak is presented on selected affected areas of Nairobi city residents who were offered the bivalent meningococcal polysaccharide vaccine against serotype A and C

Brady, JP, Awan FB, Wafula EM, Onyango FE.  1993.  Recognition of illness in very young infants by inexperienced health workers. Abstract

To determine whether inexperienced health workers can recognize severe infection in infants less than 3 months of age, a study was conducted of 200 infants with cough, fever or 'not feeling well'. The presence or absence of five symptoms: cough, difficulty in breathing, feeding problem, fever or history of convulsions, and ten signs: appearing ill, respiratory rate > or = 60/min, chest indrawing, grunting, cyanosis, wheeze, lethargy, 'too hot', 'too cold' or abdominal distension, were recorded by a health worker, who made a diagnosis of 'ill' or 'mildly ill'. Each infant was then reviewed by an experienced paediatrician who made a diagnosis of 'ill' (pneumonia, sepsis, meningitis or other severe illness) or 'mildly ill'. Using these diagnoses as the 'gold standard', the sensitivity, specificity, and positive predictive values of each parameter were calculated. In 89% of the 200 infants, the health worker made the correct diagnosis. Forty infants were admitted. In 36 instances (90%) the health worker made the correct decision. The most discriminating symptoms and signs were 'not feeding well', 'appears ill', chest indrawing and grunting. A respiratory rate > or = 60/min was 78% sensitive and 69% specific. Our study suggests that inexperienced health workers can recognize severe illness in infants under 3 months of age.

Onyango, FE, Steinhoff MC, Wafula EM, Wariua S, Musia J, Kitonyi J.  1993.  Hypoxaemia in young Kenyan children with acute lower respiratory infection., 1993 Mar 6. BMJ (Clinical research ed.). 306(6878):612-5. Abstract

To determine the prevalence, clinical correlates, and outcome of hypoxaemia in acutely ill children with respiratory symptoms.

1990

Onyango, FE, Agwanda RO, Wafula EM, Macharia WM, Mirza NM.  1990.  Verbal autopsy: a tool for determining cause of death in a community.. Abstract

Verbal autopsy was used to determine causes of death in 239 children under the age of 5 years. The diagnosis derived from verbal autopsy was corroborated with hospital diagnosis in 39 cases. There was concurrence of diagnosis in 72% of the cases. Using the diagnosis of broncho pneumonia to validate the method, verbal autopsy was found to have a sensitivity of 71%, specificity of 92%, a positive predictive value of 85%. Reliability index of agreement was 0.654. Recall period up to 29 months after death was found to be reliable.

1988

Sanii, R, Younes M.  1988.  Steady-state response of normal subjects to an inspiratory sinusoidal pressure load., 1988 Feb. Journal of applied physiology (Bethesda, Md. : 1985). 64(2):511-20. Abstract

Inspiratory duration (TI) increases during inspiratory resistive loading in conscious humans. To ascertain whether this response is related to the temporal pattern of pressure perturbation (reaching a peak in early or midinspiration and declining subsequently) we compared the response of nine normal subjects to a usual resistor (narrow tube, RES) with their response when mouth pressure was reduced in a sinusoidal fashion during inspiration (SIN). Whereas the negative pressure pattern was similar with both loads (peak negative pressure near midinspiration), there was no relation between pressure and flow in the case of sinusoidal loading. Each experiment consisted of two loading periods, 4 min each, and three unloaded periods, also 4 min each, bracketing the periods of loading. The order of RES and SIN was randomized. TI during loading was compared with the average TI of the preceding and following unloaded periods. TI increased 0.74 +/- 0.12 and 0.27 +/- 0.05 (SE) s during RES and SIN, respectively (P less than 0.01). We conclude that the temporal pattern of pressure change during resistance breathing plays a small role in mediating the TI prolongation. Coupling between flow and the pressure perturbation appears to be an important determinant of TI prolongation.

Beck, T, Höckel M, Friese K.  1988.  [Degree of placental maturity and histopathologic finding: clinical prospective studies of a sample of term births and premature births]., 1988 Jan-Feb. Zeitschrift für Geburtshilfe und Perinatologie. 192(1):24-32. Abstract

By analogy with Grannum et al.'s sonographic classification of the placenta (1979), macroscopic observation of the cut surfaces of the afterbirth enables the extent of placental segmentation to be determined and macroscopic maturity to be established in accordance with sonographic findings. Out of a total of 767 clinically-prospectively documented obstetrical cases, 674 were identified as term births and 93 as premature. For the purposes of comparison they were subdivided into two groups: term births with stage 0 to II and stage III maturity; and premature births with stage 0 to II and stage III maturity. Proceeding from this morphological classification and grouping, the clinical data, such as age of the mother, parity, gravidity, diseases during pregnancy, premature labour, type of delivery, fetal outcome, and biometric data of the newborn, as well as histologic findings regarding villous maturity, were recorded and statistically analyzed. The findings revealed no significant differences between term births with stage III maturity and those in the control group of placentas with stage 0 to II maturity and the same gestation time. Therefore, stage III maturity at term corresponds chronopathologically to a normal temporal development of fetomaternal flow units of the mature human placenta at term and does not imply any perinatological risk. Histopathologically, placentas with stage III maturity manifest a significantly advanced degree of villous maturity, with lower mean placental weight as the morphological correlate to threshold placental function, which is reflected in the clinical data of perinatological complications. Therefore, premature detection of a stage III placenta before term indicates a risk that should be kept in mind in the overall concept of prenatal monitoring parameters.

1984

1983

Ojwang, PJ;, Onyango FE;, Aluoch JA.  1983.  Hypercalcaemia in pulmonary tuberculosis. Abstract

uberculosis can affect calcium metabolism, mainly through an enhanced production of active vitamin D. The incidence of hypercalcemia among unselected patients with active pulmonary tuberculosis was investigated, retrospectively, during a ten-year period. Among 67 patients, the mean serum calcium concentration on admission was significantly raised compared to healthy controls (2.51 ± 0.16 (SD) vs 2.43 ± 0.07 mmol/l; p<0.001) and 25% of the patients had hypercalcemia. After one year of successful tuberculostatic treatment the serum calcium values had normalized Read More: http://informahealthcare.com/doi/abs/10.3109/03009739009178584

1978

Betzhold, J, Hong R.  1978.  Fatal graft-versus-host disease after a small leukocyte transfusion in a patient with lymphoma and varicella., 1978 Jul. Pediatrics. 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.

1976

  1976.  Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 1-1976., 1976 Jan 1. The New England journal of medicine. 294(1):37-42.
Holmgren, JH.  1976.  Automated laundry increases productivity., 1976 Jun. Modern healthcare. [Short-term care ed.]. 5(6):60.
Maany, I.  1976.  Tardive dyskinesia., 1976 Oct. Diseases of the nervous system. 37(10):587.
Horty, JF.  1976.  Negligence serves two masters., 1976 Jan. Modern healthcare. [Short-term care ed.]. 5(1):58-60.

1975

Peterson, DL, Gleisner JM, Blakley RL.  1975.  Bovine liver dihydrofolate reductase: purification and properties of the enzyme., 1975 Dec 2. Biochemistry. 14(24):5261-7. Abstract

A purification procedure is reported for obtaining bovine liver dihydrofolate reductase in high yield and amounts of 100-200 mg. A key step in the procedure is the use of an affinity gel prepared by coupling pteroyl-L-lysine to Sepharose. The purified reductase has a specific activity of about 100 units/mg and is homogeneous as judged by analytical ultracentrifugation, polyacrylamide gel electrophoresis, and titration with methotrexate. The products of the first step of Edman degradation indicated a minimum purity of 79%. The reductase has a molecular weight of about 21500 on the basis of amino acid composition and 22100 +/- 300 from equilibrium sedimentation. It is not inhibited by antiserum to the Streptococcus faecium reductase (isoenzyme 2). Unlike the reductase of many other vertebrate tissues, the bovine enzyme is inhibited by mercurials rather than activated and it has a single pH optimum at both low and high ionic strength. However, the position of the pH optimum is shifted and the activity increased by increasing ionic strength. Automatic Edman degradation has been used to determine 34 of the amino-terminal 37 amino acid residues. Considerable homology exists between this region and the corresponding regions of the reductase from S. faecium and from Escherichia coli. This strengthens the idea that this region contributes to the structure of the binding site for dihydrofolate.

Johnson, HA.  1975.  The demise of the Hopewellian moundbuilders: a plausible conjecture., 1975 Nov. IMJ. Illinois medical journal. 148(5):528-30.
Ignatovich, VF.  1975.  Enhancement of the antigenic activity and virulence of the vaccine strain E of Rickettsia prow azeki by passages in cell culture., 1975 Nov. Acta virologica. 19(6):481-5. Abstract

Changes in the biological properties of the vaccine strain E of Rickettsia prowazeki occurred upon cultivation of A1 (human amnion) cells infected with this strain. In the course of passages of these cells the antigenic activity and virulence of the rickettsia increased. The changes were observed in 10 out of 22 cell cultures examined: in 6 cultures there was an increase in the antigenic activity and in 4 both in the antigenic activity and in virulence. The time of the occurrence of these changes in the rickettsial populations varied from 12-18 to 53-102 days of passage of the infected cells.

Hartman, FC, LaMuraglia GM, Tomozawa Y, Wolfenden R.  1975.  The influence of pH on the interaction of inhibitors with triosephosphate isomerase and determination of the pKa of the active-site carboxyl group., 1975 Dec 2. Biochemistry. 14(24):5274-9. Abstract

Ionization effects on the binding of the potential transition state analogues 2-phosphoglycolate and 2-phosphoglycolohydroxamate appear to be attributable to the changing state of ionization of the ligands themselves, therefore it is unnecessary to postulate the additional involvement of an ionizing residue at the active site of triosephosphate isomerase to explain the influence of changing pH on Ki in the neutral range. The binding of the competitive inhibitor inorganic sulfate is insensitive to changing pH in the neutral range. 3-Chloroacetol sulfate, synthesized as an active-site-specific reagent for triosephosphate isomerase, is used to provide an indication of the pKa of the essential carboxyl group of this enzyme. Previously described active-site-specific reagents for the isomerase were phosphate esters, and their changing state of ionization (accompanied by possible changes in their affinity for the active site) may have complicated earlier attempts to determine the pKa of the essential carboxyl group from the pH dependence of the rate of inactivation. Being a strong monoprotic acid, chloroacetol sulfate is better suited to the determination of the pKa of the carboxyl group. Chloroacetol sulfate inactivates triosephosphate isomerase by the selective esterification of the same carboxyl group as that which is esterified by the phosphate esters described earlier. From the pH dependence of the rate of inactivation of yeast triosephosphate isomerase, the apparent pKa of the active-site carboxyl group is estimated as 3.9 +/- 0.1.

Ris, MM, Deitrich RA, Von Wartburg JP.  1975.  Inhibition of aldehyde reductase isoenzymes in human and rat brain., 1975 Oct 15. Biochemical pharmacology. 24(20):1865-9.
Weiss, JM, Glazer HI, Pohorecky LA, Brick J, Miller NE.  1975.  Effects of chronic exposure to stressors on avoidance-escape behavior and on brain norepinephrine., 1975 Nov-Dec. Psychosomatic medicine. 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.

Orskov, ER, Fraser C.  1975.  The effects of processing of barley-based supplements on rumen pH, rate of digestion of voluntary intake of dried grass in sheep., 1975 Nov. The British journal of nutrition. 34(3):493-500. Abstract

1. In one experiment the effect on rumen pH of feeding with restricted amounts of whole or pelleted barley was studied. With whole barley there was little variation in rumen pH associated with feeding time, but with pelleted barley the pH decreased from about 7-0 before feeding to about 5-3, 2--3 h after feeding. 2. The rate of disappearance of dried grass during incubation in the rumens of sheep receiving either whole or pelleted barley was studied in a second experiment. After 24 h incubation only 423 mg/g incubated had disappeared in the rumen of sheep receiving pelleted barley while 625 mg/g incubated had disappeared when it was incubated in the rumen of sheep receiving whole barley. 3. The voluntary intake of dried grass of lambs was studied in a third experiment when they received supplements of either 25 or 50 g whole or pelleted barley/kg live weight 0-75. At the high level, pelleted barley reduced intake of dried grass by 534 g/kg but whole barley reduced it by only 352 g/kg. The digestibility of acid-detergent fibre was reduced more by pelleted barley than by whole barley but there was a tendency for a small increase in digestibility of the barley due to processing. 4. The implications of these findings on supplementation of roughages with cereals are discussed.

Sprenger, KJ, Chouler CA.  1975.  The GP dilemma. Recommendations and synopsis of a student conference., 1975 Nov 15. South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde. 49(49):2059-60. Abstract

The proceedings of a conference organised by students are reported. The present standing of the general practitioner and his need in different societies are equated and the obvious deficiencies are considered. Such themes as maldistribution, service and education are discussed. Resolutions derived from the conference are reported in full.

Odelola, HA, Koza J.  1975.  Characterization of Nigerian strains of West Nile virus by plaque formation., 1975 Nov. Acta virologica. 19(6):489-92. Abstract

Seven strains of West nile virus isolated in Nigeria were investigated for their ability to form plaques in monkey kidney cell monolayers. Five strains antigenically related to one another produced plaques of about the same size 3 to 4 days after the addition of the overlay medium. The two other strains closely related to each other produced no plaques. Their inability to produce plaques was regarded as a significant characteristic of the intratypic group to which the two strains belong.

Slotkin, TA, Seidler FJ.  1975.  Acute and chronic effects of nicotine on synthesis and storage of catecholamines in the rat adrenal medulla., 1975 May 15. Life sciences. 16(10):1613-22.
Tan, AW, Nuttall FQ.  1975.  Characteristics of the dephosphorylated form of phosphorylase purified from rat liver and measurement of its activity in crude liver preparations., 1975 Nov 20. Biochimica et biophysica acta. 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.

Dorofeyeva, LV.  1975.  Obtaining of measles virus haemagglutinin from strain L-16 grown in primary cell cultures., 1975 Nov. Acta virologica. 19(6):497.
Stites, DP, Caldwell J, Carr MC, Fudenberg HH.  1975.  Ontogeny of immunity in humans., 1975 Nov. Clinical immunology and immunopathology. 4(4):519-27.
Siddiqui, KA, Banerjee AK.  1975.  Fructose 1,6-bisphosphate aldolase activity of Rhizobium species., 1975. Folia microbiologica. 20(5):412-7. Abstract

FDP aldolase was found to be present in the cell-free extracts of Rhizobium leguminosarum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium meliloti, Rhizobium lupini, Rhizobium japonicum and Rhizobium species from Arachis hypogaea and Sesbania cannabina. The enzyme in 3 representative species has optimal activity at pH 8.4 in 0.2M veronal buffer. The enzyme activity was completely lost by treatment at 60 degrees C for 15 min. The Km values were in the range from 2.38 to 4.55 X 10(-6)M FDP. Metal chelating agents inhibited enzyme activity, but monovalent or bivalent metal ions failed to stimulate the activity. Bivalent metal ions in general were rather inhibitory.

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