Designers, architects and artists have invariably relied on their portfolios to record their work and to exhibit their capabilities. Unfortunately there is very little reference from which to draw tips on how to effectively utilize a portfolio. Sometimes the attention given to the production of the work is not complemented with strong oral and visual, presentations. The continued failure to pay due attention to portfolio has led to loss of job opportunities. The portfolio can open doors and close them with equal speed. To people shopping for jobs, it's a calling card, the advance guard, the marketing tool, often the only opportunity to make an impression. Many companies do not hire people but rather hire portfolios. When a prospective employer requests for a portfolio it is because they are seeking certain attributes or traits that may be of service to them. Typically, the employer will say they are looking for somebody "creative". How does your portfolio show that you are creative? Is it in the way it is organized? The work you have put in it? Or is it the bag/booklet? The answer to this is "all of the above". It does not do good work justice if it's put together in a tattered envelope. Neither can a very expensive bag/booklet camouflage bad work. There must be a sense of your presence in the work you do, the way you do it, the way you present it and what you want to do with it. And, not to forget, what you want the work to do for you.

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BACKGROUND: The onset of colorectal cancer appears to be two to three decades earlier in developing countries. Data on whether colorectal cancer in the young has worse prognosis than in older patients is conflicting.
METHOD: Clinical charts of 70 patients ≤40 years old were reviewed to determine clinical and pathological patterns and treatment outcomes. Their data were compared with a
larger group of older patients treated between 1993-2005 at Kenyatta National Hospital in Nairobi, Kenya.
RESULTS: The data retrieval was highest for sub-site distribution and lowest for pathology information. Patients ≤ 40 years of age comprised 27.3% of all colorectal cancer
cases treated over the study period. There were 41 males (58.6%) and 29 (41.4%) females patients. The most common symptoms were abdominal pain (76.9%), change in bowel habit
(71.4%) and rectal bleeding (54.3%). The mean duration of symptoms was 24.6 ± 30 months. The rate of advanced colorectal disease (Duke C and D) was 73.5%. Mean follow-up time was 5.8 months with median survival of only 6.9
months. The Duke staging, histology, symptom duration, locations of tumours, follow-up and the complication rates were similar for young and older patients.
CONCLUSION: Younger patients form a significant proportion of colorectal cancer burden. Both the clinico-pathological
characteristics and treatment outcome correspond to older individuals. It is suggested that the concluded colorectal symptoms in younger patients should also be aggressively
evaluated including early endoscopy. A prospective follow-up study of patients with the disease will unravel the true survival picture

Possession of beta-1-selectivity and intrinsic sympathomimetic activity (ISA) by beta-adrenergic blocking drugs have been found to modify the effects of these drugs on heart rate, blood pressure and pulmonary airway resistance both at rest and during exercise. In a randomised, double-blind, cross-over, placebo-controlled trial, 21 healthy male volunteers took placebo, propranolol (non-selective with no ISA), metoprolol (beta-1-selective with no ISA) and pindolol (non-selective with ISA) on separate occasions prior to an exercise test using the same protocol each time. Heart rate, blood pressure and peak respiratory flow rate (PEFR) were measured before exercise and at exhaustion. No significant differences in percentage increase in heart rate after exercise were detected between placebo and all the three beta-blockers. All three drugs were associated with significantly lower percentage increases in systolic blood pressure with exercise compared to placebo; with metoprolol and propranolol causing lower increases than pindolol. The index of myocardial oxygen consumption, MVO2, was highest with pindolol. PEFR was reduced most by propranolol. Possession of beta-1-selectivity and ISA by beta-blocking drugs modifies their effects on cardio-respiratory responses to exercise amongst indigenous Kenyans.

PMID: 614126 [PubMed - indexed for MEDLINE]

In semi arid Kenya, the occurrence of flush floods and soil erosion on agricultural watersheds is attributed to intense rainstorm events of short duration. Thus when agricultural watersheds have no erosion control structures in place, the generation of direct runoff would increase with cultivation. Of the two components of runoff namely, runoff volume and peak runoff discharge, the consideration of peak runoff discharge rate is critical to the design of effective hydraulic structures for controlling floods and soil erosion. In order to accurately predict a watershed's peak runoff discharge, it is important to select a model that is deterministic and yet simple to use. The model should be able to consider the time distribution of runoff response as influenced by Watershed characteristics. The time to peak runoff discharge is largely influenced by the time of concentration. The time of concentration depends on the shape, size and relief of the watershed. In Iiuni Watershed, the Nash model, a parsimonious deterministic model, was selected to predict peak runoff discharges. This model uses the instantaneous unit hydrograph principle to simulate the direct runoff hydrographs and estimate peak runoff discharge. The Nash model was applied using input parameters derived from the watershed's rainfall-runoff characteristics. The results obtained showed that the Nash model was good in predicting peak runoff discharges. This statistic of comparison, R2 (coefficient of efficiency) for the model was above 70% for the model which is indicative of good model prediction of peak runoff discharge (Nash and Sutcliffe, 1970). From this analysis, the Nash model is recommended for the estimation of peak runoff discharge from un-gauged agricultural watersheds in Kenya.

A retrospective study of the hospital records revealed that 39 cases of mandibular fractures presented at Kisii District Hospital during a two-year period. 27 cases were due to interpersonal violence while road traffic accidents and accidental falls accounted for 9 and 3 of the cases respectively. The male ratio was 2.9:1. Majority (26 cases) of the patients were aged between 20 and 39 years. The commonly involved fracture site was the left body of the mandible accounting for 20 of the fractures.

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.

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.

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The gene Q13L coding for the Capripoxvirus group specific structural protein P32 was expressed in Escherichia coli using plasmid pGEX-2T as a fusion protein with glutathione-s-transferase and purified on glutathione sepharose affinity chromatography column. The protein was then employed for diagnosis of sheeppox, goatpox and lumpyskin disease, by a latex agglutination test (LAT) using the purified P32 antigen and guinea pig detector antiserum raised against the P32 antigen. The LAT and virus neutralization test (VNT) were used to screen one hundred livestock field sera for antibodies to Capripoxvirus, in comparison the LAT was simpler, rapid and 23% more sensitive than the VNT. In addition the LAT was found to be specific for Carpripoxvirus because it did not pick antibodies to Orthopoxvirus and Parapoxvirus. The LA test can be taken for a simple and quick diagnostic tool for primary screening of Carpripoxvirus infection and will reduce the reliance of diagnostic laboratories on tissue culture facilities. Keywords: Carpripox, latex agglutination test, attachment gene J. Trop. Microbiol. Biotechnol. Vol. 3 (2) 2007: pp. 36-43

This paper describes the methodology and presents preliminary results of an economic appraisal of a community based health care project in Kenya. Community health workers, trained for 12 weeks and deployed in two locations in Kenya's Western Province, act as first contact providers of basic health care and promoters of selected health, sanitation and nutrition practices. A Cost Benefit Analysis has been undertaken using the Willingness to Pay approach to compare the costs of the project and its benefits. The benefits are in the form of more easily accessible basic health care and are measured as consumer surplus accruing to the community. Gain in consumer surplus is consequent on the fall of average user costs and rise in utilisation of the project established points of first contact with primary health care. The argument for the economic viability of the project is validated by the large Net Present Value and Benefit Cost Ratio obtained for the whole of the project area and for the two locations separately. Although the evaluation technique used faces the problem of valuation of community time, aggregation of health care services at all points of first contact and the partial nature of cost benefit analysis evaluations, the results are strongly in favour of decentralisation of primary health care on similar lines in the rest of the country.

Normal 0 false false false MicrosoftInternetExplorer4 st1:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Macrophytes have been shown to perform important ecological roles in Lake Naivasha. Consequently, various studies regarding the impact of biotic factors on the macrophytes have been advanced but related studies on environmental parameters have lagged behind. In an attempt to address this gap, sampling on floating species and submergents was carried out in eight sampling sites in 2003 to investigate how they were influenced by a set of environmental factors. Soil texture (sandy sediments; P < 0.05, regression coefficient = - 0.749) and wind were the most important environmental parameters influencing the distribution and abundance of floating macrophytes. Combination of soil texture and lake-bed slope explained the most (86.3%) variation encountered in the submergents. Continuous translocation of the floating dominant water hyacinth to the western parts by wind has led to displacement of the submergents from those areas. In view of these findings, the maintenance and preservation of the steep Crescent Lake basin whose substratum is dominated by sand thus hosting most submergents remain important, if the whole functional purpose of the macrophytes is to be sustained.

A cross sectional study of 115 patients admitted at the Department of Orthopedics, Kenyatta National Hospital, Nairobi, Kenya was carried out to determine the prevalence and antibiotic susceptibility of Staphylococcus aureus isolated from infected wounds. The prevalence of Staphylococcus aureus was 33.0 %. The drugs tested and their corresponding sensitivity was amoxycillin (13.2 %), co-amoxyclav (39.5 %), oxacillin (55.3 %), erythromycin (44.7 %), gentamicin (60.5 %), ciprofloxacin (62.2 %), minocycline (86.8 %), cefuroxime (57.9 %), and clidamycin (84.2 %). These results show the sensitivity profile of Staphylococcus aureus and can be used to choose suitable drugs in the management of wounds for hospitalized patients.

A cross sectional study of 115 patients admitted at the Department of Orthopedics, Kenyatta National Hospital, Nairobi, Kenya was carried out to determine the prevalence and antibiotic susceptibility of Staphylococcus aureus isolated from infected wounds. The prevalence of Staphylococcus aureus was 33.0 %. The drugs tested and their corresponding sensitivity was amoxycillin (13.2 %), co-amoxyclav (39.5 %), oxacillin (55.3 %), erythromycin (44.7 %), gentamicin (60.5 %), ciprofloxacin (62.2 %), minocycline (86.8 %), cefuroxime (57.9 %), and clidamycin (84.2 %). These results show the sensitivity profile of Staphylococcus aureus and can be used to choose suitable drugs in the management of wounds for hospitalized patients.

A cross sectional study of 115 patients admitted at the Department of Orthopedics, Kenyatta National Hospital, Nairobi, Kenya was carried out to determine the prevalence and antibiotic susceptibility of Staphylococcus aureus isolated from infected wounds. The prevalence of Staphylococcus aureus was 33.0 %. The drugs tested and their corresponding sensitivity was amoxycillin (13.2 %), co-amoxyclav (39.5 %), oxacillin (55.3 %), erythromycin (44.7 %), gentamicin (60.5 %), ciprofloxacin (62.2 %), minocycline (86.8 %), cefuroxime (57.9 %), and clidamycin (84.2 %). These results show the sensitivity profile of Staphylococcus aureus and can be used to choose suitable drugs in the management of wounds for hospitalized patients.

Soil water conservation through tillage is widely accepted as one of the ways of improving crop yields in rainfed agriculture. Field experiments were conducted between 2007 and 2009 to evaluate the effects of conservation tillage on the yields and crop water use efficiency of maize (Zea mays L.) and cowpea (Vigna unguiculata L.) in eastern Kenya. Experimental treatments were a combination of three tillage practices and four cropping systems. Tillage practices were tied-ridges, subsoiling-ripping and ox-ploughing. The cropping systems were single crop maize, single crop cowpea, intercropped maize–cowpea and single crop maize with manure. The treatments were arranged in split plots with tillage practices as the main plots and cropping systems as the sub-plots in a Randomized Complete Block Design (RCBD). The results showed that tied-ridge tillage had the greatest plant available water content while subsoiling-ripping tillage had the least in all seasons. Averaged across seasons and cropping season, tillage did not have a significant effects on maize grain yield but it did have a significant effect on crop grain and dry matter water use efficiency (WUE). Nevertheless, maize grain yields and WUE values were generally greater under tied-ridge tillage than under subsoiling-ripping and ox-plough tillages. The yields and WUE of cowpea under subsoiling-ripping tillage were less than those of ox-plough tillage. When averaged across the seasons and tillage systems, the cropping system with the manure treatment increased (P ≤ 0.05) maize grain yield, grain WUE and dry matter WUE by 36%, 30%, 26% respectively, compared to treatments without manure. Maize and cowpea when intercropped under ox-plough and ripping tillage systems did not have any yield advantage over the single crop.Highlights ► We studied crop yield and water use efficiencies of maize and cowpea under different tillage practices in semi-arid Kenya. ► Plant available water was highest in tied ridges, followed by ox-ploughing and least in the ripping tillage system. ► Tillage did not have significant effects on maize grain yield and but it had on crop water use efficiency. ► Cowpea yielded less under ripping than ox-ploughing. ► Maize yield was reduced by intercropping but was improved by manure application.

Sixty newly diagnosed adult patients with mild to moderate essential hypertension were assessed to determine their cardiovascular risk factor profiles. Detailed history and physical examinations were done. Resting 12-lead ECG was done and serum levels of uric acid, fasting cholesterol, and fasting glucose were determined. Twenty nine patients had hypertension and two or more cardiovascular risk factors. The most prevalent cardiovascular risk factors other than hypertension were electro-cardiovascular left ventricular hypertrophy (31.7%), obesity (28.3%) and hypercholesterolaemia (28.3%). About a half of these patients (48.3%) can be classified as high risk hypertensives. This calls for aggressive management of cardiovascular risk factors as a whole and not just hypertension alone if we are to reduce incidence of hypertensive complications.

Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya

In a prospective single-blind comparative trial, sixty newly diagnosed mild to moderate hypertensives were randomly assigned to either propranolol or hydroflumethiazide monotherapy. Baseline fasting serum glucose lipid profiles, serum uric acid and potassium levels, were determined at the beginning of the trial. Repeat levels were determined at completion of twelve weeks of treatment. Propranolol treatment significantly reduced HDL-cholesterol (p < 0.02) and increased both VLDL and total serum triglycerides (p < 0.01). Hydroflumethiazide significantly increased total and LDL-chole-sterol, fasting serum glucose and uric acid levels (p < 0.01); potassium levels were significantly lowered (p < 0.01). Treatment with either propranolol or hydroflumethiazide is associated with significant metabolic side-effects which require regular monitoring and intervention as appropriate.

In a prospective single-blind comparative trial, sixty newly diagnosed mild to moderate hypertensives were randomly assigned to either propranolol or hydroflumethiazide monotherapy. Baseline fasting serum glucose lipid profiles, serum uric acid and potassium levels, were determined at the beginning of the trial. Repeat levels were determined at completion of twelve weeks of treatment. Propranolol treatment significantly reduced HDL-cholesterol (p < 0.02) and increased both VLDL and total serum triglycerides (p < 0.01). Hydroflumethiazide significantly increased total and LDL-chole-sterol, fasting serum glucose and uric acid levels (p < 0.01); potassium levels were significantly lowered (p < 0.01). Treatment with either propranolol or hydroflumethiazide is associated with significant metabolic side-effects which require regular monitoring and intervention as appropriate.

Sixty newly diagnosed adult patients with mild to moderate essential hypertension were assessed to determine their cardiovascular risk factor profiles. Detailed history and physical examinations were done. Resting 12-lead ECG was done and serum levels of uric acid, fasting cholesterol, and fasting glucose were determined. Twenty nine patients had hypertension and two or more cardiovascular risk factors. The most prevalent cardiovascular risk factors other than hypertension were electro-cardiovascular left ventricular hypertrophy (31.7%), obesity (28.3%) and hypercholesterolaemia (28.3%). About a half of these patients (48.3%) can be classified as high risk hypertensives. This calls for aggressive management of cardiovascular risk factors as a whole and not just hypertension alone if we are to reduce incidence of hypertensive complications.

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Department of Medicine, Faculty of Medicine, University of Nairobi, Kenya. In a prospective single-blind comparative trial, sixty newly diagnosed mild to moderate hypertensives were randomly assigned to either propranolol or hydroflumethiazide monotherapy. Baseline fasting serum glucose lipid profiles, serum uric acid and potassium levels, were determined at the beginning of the trial. Repeat levels were determined at completion of twelve weeks of treatment. Propranolol treatment significantly reduced HDL-cholesterol (p < 0.02) and increased both VLDL and total serum triglycerides (p < 0.01). Hydroflumethiazide significantly increased total and LDL-chole-sterol, fasting serum glucose and uric acid levels (p < 0.01); potassium levels were significantly lowered (p < 0.01). Treatment with either propranolol or hydroflumethiazide is associated with significant metabolic side-effects which require regular monitoring and intervention as appropriate.

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Separation of midgut membrane proteins from the tick, Ambylomma variegatum, using a nonionic detergent (Triton X-114), resulted in two protein fractions, namely DET (detergent) and AQ (aqueous). In immunoblotting analysis with polyclonal antibodies against these fractions, 4 proteins (Mr approximately 27,000, 67,000, 86,000 and 95,000,) and 2 proteins (M, approximately 54,000 and 67,000) were detected in the DET and AQ fractions, respectively. Three of the DET fraction proteins Mr approximately 27,000, 67,000 and 95,000 were glycosylated since they bound to the lectin, concanavalin A. In 2-dimensional gel electrophoresis, the AQ and DET fraction proteins were found to be acidic in nature. In a series of bioassay experiments, rabbits were first immunised with both DET and AQ fractions and then infested with ticks. The egg batch weights of these ticks were reduced by 50% compared to control ticks. Furthermore, there was a significant reduction in the hatchability of eggs laid by ticks fed on rabbits previously immunised with both DET (14%) and AQ (33%) fractions. Based on the egg hatchability, the reproductive capacity of ticks was reduced by 77 and 48% by DET and AQ fractions, respectively.

Serum acid phosphatase was measured in patients with enlarged benign and malignant prostate before and after rectal examination. Amongst the patients with benign glands, rectal examination did not produce any significant false elevation of the enzyme. Rectal examination, however, caused a rise in the enzyme level in a few untreated cancer patients and in cancer patients who has become refractory to hormonal therapy. This rise would help rather than mislead in the diagnosis of malignant prostate and also in the identifying treated patients who had become refractory to treatment. Thus, when serum acid phosphatase is properly determined, elevated levels should always arouse suspicion of malignant prostate or other lesions associated with high enzyme level even is such determination was preceded by rectal examination. There appears to be no merit in the teaching that the determination of serum acid phosphatase should be delayed after rectal examination.

Although a relationship between Lapiat and post-Lapita ceramic traditions has long been suspected, a systematic and detailed examination of the similarities and differences has not been previously made. An important first step is to determine the nature of change from one to the other by examining pottery from sites which have the full ceramic sequence. My analyses of the assemblages from Manus and New Island demonstrate continuity between the two traditions.

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BACKGROUND: The onset of colorectal cancer appears to be two to three decades earlier in developing countries. Data on whether colorectal cancer in the young has worse prognosis than in older patients is conflicting.
METHOD: Clinical charts of 70 patients ≤40 years old were reviewed to determine clinical and pathological patterns and treatment outcomes. Their data were compared with a
larger group of older patients treated between 1993-2005 at Kenyatta National Hospital in Nairobi, Kenya.
RESULTS: The data retrieval was highest for sub-site distribution and lowest for pathology information. Patients ≤ 40 years of age comprised 27.3% of all colorectal cancer
cases treated over the study period. There were 41 males (58.6%) and 29 (41.4%) females patients. The most common symptoms were abdominal pain (76.9%), change in bowel habit
(71.4%) and rectal bleeding (54.3%). The mean duration of symptoms was 24.6 ± 30 months. The rate of advanced colorectal disease (Duke C and D) was 73.5%. Mean follow-up time was 5.8 months with median survival of only 6.9
months. The Duke staging, histology, symptom duration, locations of tumours, follow-up and the complication rates were similar for young and older patients.
CONCLUSION: Younger patients form a significant proportion of colorectal cancer burden. Both the clinico-pathological
characteristics and treatment outcome correspond to older individuals. It is suggested that the concluded colorectal symptoms in younger patients should also be aggressively
evaluated including early endoscopy. A prospective follow-up study of patients with the disease will unravel the true survival picture.

Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} Products of gene modification have vast implications. Creating public awareness and disseminating information on the subject seeks to demystify some of the widely held falsehoods regarding genetically modified products. This is an informative, thorough and easy to understand guidebook that aims to enlighten and debunk some of the commonly held misconceptions on products of gene modification and to give the reader a better understanding of the role genetic modification will play. The review sheds light on the safety, and application of these products in medicine, the food industry and other areas, especially those where genetic modification may represent a cheap, faster, credible, viable alternative in achieving sustainable development among resource-poor communities.

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In contrast with mammalian cells, little is known about the control of Ca2+ entry into primitive protozoans. Here we report that Ca2+ influx in pathogenic Trypanosoma brucei can be regulated by phospholipase A2 (PLA2) and the subsequent release of arachidonic acid (AA). Several PLA2 inhibitors blocked Ca2+ entry; 3-(4-octadecyl)-benzoylacrylic acid (OBAA; IC50 0.4+/-0.1 microM) was the most potent. We identified in live trypanosomes PLA2 activity that was sensitive to OBAA and could be stimulated by Ca2+, suggesting the presence of positive feedback control. The cell-associated PLA2 activity was able to release [14C]AA from labelled phospholipid substrates. Exogenous AA (5-50 microM) also initiated Ca2+ entry in a manner that was inhibited by the Ca2+ antagonist La3+ (100 microM). Ca2+ entry did not depend on AA metabolism or protein kinase activation. The cell response was specific for AA, and fatty acids with greater saturation than tetraeicosanoic acid (AA) or with chain lengths less than C20 exhibited greatly diminished ability to initiate Ca2+ influx. Myristate and palmitate inhibited PLA2 activity and also inhibited Ca2+ influx. Overall, these results demonstrate that Ca2+ entry into T. brucei can result from phospholipid hydrolysis and the release of eicosanoic acids.