Mouse cytokine profile skewed towards Th2 in pregnancy during infection with Brucella abortus S19 strain

The two classes of cytokines Th1 and Th2 determine the type of immune response elicited. The Th2 immune response is associated with successful pregnancy. Brucellosis is an intracellular bacterium that elicits the Th1 response and is known to cause spontaneous abortion in mammalian species. This study sought to determine if Brucella infection causes spontaneous abortion by causing the circulating cytokine profile be Th1 dominant during pregnancy. Forty-eight Swiss white mice were used in this murine model and the S19 strain of Brucella abortus was used in as the infective agent. Pregnant mice in the test group were injected intraperitoneally with 105-8 CFU of Brucella and cytokine profile evaluated over the three trimesters of pregnancy. Pregnant mice in the control group were left to go through normal pregnancy and their cytokine profile evaluated over the three trimesters of pregnancy. Cytokines in serum samples were analyzed by Cytometric Bead Array. The data was analyzed using the Paired T- test and

Prospective Changes in Serum Levels of Some Proinflammatory Cytokines and Erythropoietin among Anaemic HIV-infected Patients Attending Kenyatta National Hospital Comprehensive Care Centre

Between 70 to 80% of HIV infected patients develop anaemia which is a major complication in advanced HIV infection. The multifactorial etiology of the HIV-associated anaemia requires extensive studies on its unique pathophysiology as a step towards improving therapeutic options and disease management.The objective of this study is to monitor changes in serum levels of erythropoietin (Epo), Tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6), C-Reactive Protein (CRP) and anaemia in HIV infected patients over six months’ period. This study is Longitudinal descriptive study and it was conducted at Kenyatta National Hospital, Kenyatta National Hospital can be considered as Comprehensive Care Centre.The study used one hundred and eighty-four (184) seropositive adults aged 18 to 60 years.The results shows that Blood cells exhibited pathologies ranging from: Rouleaux formation, round macrocytes, microcytic hypochromic cells and target cells in frequencies that decreased with increase in CD4+ cells. Normochromic, macrocytic normochromic and dimorphic anaemias were observed. Bicytopenia (erythrocytopenia and leucopenia), reactive thrombocytosis with giant platelets, neutrophil and eosinophil hypersegmentations were also observed. Persistent increase in Epo and CRP levels were demonstrated among subjects throughout the study period. Increases in TNF-α levels without corresponding increase in IL-6 levels were observed. Persistence anaemia in presence of high Epo levels is suggestive of hyposensitivity to Epo by erythroid precursors. Asynchronized increases in TNF-α and IL- 6 levels may have deprived the duo the synergy required to effectively inhibit Epo production further facilitating the escalating levels of Epo observed. High levels of CRP observed indicate enhanced inflammation processes associated with HIV infection. Iron studies to rule out the role of iron-restricted erythropoiesis in the development microcytic, dimorphic anaemias and the granulocytic hypersegmentations noted are recommended. Studies on the possibility of Epo hyposensitivity derailing the effectiveness of recombinant human Epo in the management of HIV – associated anaemia are recommended.       

Determination of Pesticide Residues in Locally Consumed Vegetables in Kenya

Background: Pesticides are being used today to control a variety of insects, weeds and plant diseases. Some of these pesticides can act as toxins to plants, animals and humans when found in significant concentrations. Objective: The purpose of this study was to determine pesticide residues in locally consumed vegetables. This was done by analyzing vegetable samples from supermarkets and local markets in Nairobi and its environs. Materials and methods: A total of 112 samples (kales 94, French beans 18) were collected from the study area and analyzed using gas chromatography for pesticide residues. Samples collection was done during the hot/dry season and cold/wet season. Results: The pesticide residues were found especially during the hot/dry season and were mainly organophosphates. However, on washing and cooking the residue levels reduced were by 17% and 40% -respectively. Adherence to recommended pre harvest intervals resulted in 99% reduction of the pesticide residues. Conclusion: This study clearly shows that adherence to good agricultural practice would significantly lower the levels of pesticide residues in vegetables. Keywords: Pesticides residues, vegetable

Analgesic potential of dichloromethane leaf extracts of Eucalyptus globulus (Labill) and Senna didymobotrya (Fresenius) in mice models

Introduction: Pain is managed using conventional drugs like paracetamol, aspirin and diclofenac among others. Synthetic drugs have many side effects. This study aimed at evaluating the analgesic potential of the dichloromethane leaf extracts of Eucalyptus globulus and Senna didymobotrya in mice. Methods: The dichloromethane leaf extracts of E. globulus and S. didymobotrya were subjected to quantitative phytochemical analysis using gas chromatography-mass spectrophotometry (GC-MS). In vivo analgesic evaluation comprised of nine groups of animals (Swiss albino mice): normal, positive, negative control and six experimental groups that received 25, 50, 100, 150, 200 and 250 mg/kg body weight of each plant extract intraperitoneally. Thirty minutes later, they were injected with 0.01 mL of 2.5% formalin. The animals in positive control group were administered diclofenac (15 mg/kg) and formalin, the normal control mice received 3% dimethyl sulfoxide (DMSO) in normal saline, while the negative group received DMSO in normal saline and formalin. All the doses were administered intraperitoneally. The duration of shaking and licking of the injected paw was scored and analyzed. Results: The analysis revealed that E. globulus contained alpha-pinenes, endo-fenchol, α-eudesmol, myrcene, camphene, alpha-phellandrene, limonene, and camphor while S. dymobotrya possessed camphene, alpha-phellandrene, limonene, and camphor. In the late phase, E. globulus at the doses of 25, 50, 100, 150, 200 and 250 mg/kg reduced the paw licking time by 34.03%, 60.79%, 84.33 %, 90.65%, 94.49%, 98.52%, respectively while S. didymobotrya extract reduced the paw licking time by 26.48%, 32.96%, 87.04%, 91.27%, 93.40%, 90.97%, and 96.82%, respectively. Conclusion: The results of this study validate and support the traditional uses of these plants as analgesics

Mouse cytokine profile skewed towards Th2 in pregnancy during infection with Brucella abortus S19 strain

The two classes of cytokines Th1 and Th2 determine the type of immune response elicited. The Th2 immune response is associated with successful pregnancy. Brucellosis is an intracellular bacterium that elicits the Th1 response and is known to cause spontaneous abortion in mammalian species. This study sought to determine if Brucella infection causes spontaneous abortion by causing the circulating cytokine profile be Th1 dominant during pregnancy. Fortyeight Swiss white mice were used in this murine model and the S19 strain of Brucella abortus was used in as the infective agent. Pregnant mice in the test group were injected intraperitoneally with 105-8 CFU of Brucella and cytokine profile evaluated over the three trimesters of pregnancy. Pregnant mice in the control group were left to go through normal pregnancy and their cytokine profile evaluated over the three trimesters of pregnancy. Cytokines in serum samples were analyzed by Cytometric Bead Array. The data was analyzed using the Paired T-test and p<0.05 was considered significant. IFN-γ and TNF-α represented the Th1 cytokines while IL-4 and IL-5 represented the Th2 cytokines. None of the mice in the test group had spontaneous abortion. IFN-γ and TNF-α had no significant differences between cytokine levels for infected and uninfected groups in all 3 trimesters of pregnancy. IL-4 levels had significant differences in all three trimesters of pregnancy (t =13, P=0.036, 0.0071 and 0.0277). IL-5 levels had significant differences second trimester (t=14, P=0.0075). The cytokine profile was robustly Th2. In conclusion, Brucella abortus cannot cause spontaneous abortion by altering the mouse cytokine profile towards ThI in pregnancy. Elevated IL-4 levels with corresponding suppression of IFN-γ can be used as a marker for successful pregnancy in Brucellosis

Effi cacy of Allopatric Tephrosia Vogelii (Fabales: Fabaceae) against Pre-Emerginal Stages of Phlebotomus (Phlebotomus) Duboscqi (Diptera: Psychodidae)

The effi cacy of allopatric Tephrosia vogelii in killing eggs and larvae of the sand fl y Phlebotomus duboscqi was tested in the laboratory. In this study effects of both water and crude powder extracs of Tephrosia vogelii were tested against against pre-emerginal stages of P. duboscqi in the laboratory. Three groups of eggs were wetted with T. vogelii extracts from Kilifi (TVK), Nairobi (TVN) and Vihiga Counties (TVV) and observed for morphological changes, motility, transformation and death. Six groups of 30 first instar larvae were fed on T. vogelii crude powder either alone or mixed with larvae food. All larvae given TVN powder become immortile, did not feed and died at the fi rst instar stage, whereas those fed on TVV and TVK did not die. Combining all the three extracts also led the death of all fi rst and second instar larvae, but gradual death and disintegration of third instar larvae was sequentially observed. The differences in activities of the allopatric plants can be attributed to allopatric introgression arising from geopgraphic separation leading to introgressive hybridization. The killing and anti-feedant activities of TVN could also mean that it is a chemotype 1 plant that contains rotenoid whereas TVK and TVV are chemotype 2 that lack rotenoids. Feeding deterrence has been shown to be caused by rutin and quercetin. Considering that only leaves were used, the toxicity of TVN can be attributed to single or combination actions of rotenone, elliptone, deguelin, rutin, rotenolone, tephrosin or quercetin that have been shown to be present in leaves. Results of this study suggest that T. vogelli has detrimental insecticidal effects on pre-emerginal stages of P. duboscqi and has potential for sand fl y control. This control method can be achieved through direct introduction of crude dried T. vogelii powder into termite mound ventilation shafts and animal burrows where sand fl ies are known to breed and rest.</p

Comparison of short-term and long-term protocols for stabilization and preservation of RNA and DNA of Leishmania, Trypanosoma, and Plasmodium

Molecular tools continue to be important in the prevention and control of parasitic diseases. However, using these techniques directly in the field remains a major challenge. Therefore, the preservation of clinical samples collected from endemic field areas for later analysis remains an important preanalytical process. This study aimed at identifying a suitable protocol for stabilization and preservation of RNA and DNA in bioclinical specimens for Trypanosoma, Leishmania, and Plasmodium research. Both spiked and unspiked blood samples were preserved in 7 protocols (different media; storage temperatures). Samples were evaluated for possible degradation of DNA and RNA along the storage duration up to the 10th week. Nucleic acid targets were assessed as follows: (i) Trypanosoma and Plasmodium RNA analysis was done using real-time nucleic acid sequence-based amplification (RT-NASBA) for 18S rRNA and for stage-specific Pfs25 mRNA, respectively; (ii) Trypanosoma DNA assessment analysis was conducted by using a conventional PCR for 18S rDNA; (iii) Leishmania RNA analysis was performed with a quantitative NASBA for 18S rRNA and Leishmania DNA assessment with an RT-PCR for 18S rDNA. Findings suggested that a newly developed L3™ buffer proved to be reliable and suitable for both short- and long-term preservation of parasite nucleic acid material. This buffer is envisaged to be suitable for utilization in field situations where resources are limite

Molecular characterization of group A rotaviruses in Mukuru slums Kenya: detection of novel strains circulating in children below 5 years of age

Abstract Background Gastroenteritis is a public health concern due to high morbidity and mortality among children. Rotaviruses are the leading etiological agents of severe gastroenteritis in children and accounts for more than half a million deaths per year in Africa. The study aimed at investigating the rotavirus genotypes that were circulating in children aged 5 years and below in and around Mukuru slums in Nairobi County Kenya. Methods A purposive cross sectional sampling method was applied where 166 samples were collected from children below 5 years of age and taken to Kenya Medical Research Institute virology laboratory. Presence of rotaviruses was determined using reverse transcription polymerase chain reaction, while extraction was done using ZR Soil/Fecal RNA MicroPrep™ extraction kit. This was followed by reverse transcription and genotyping using various group A rotavirus primers. Results The G type was successfully determined in 37 (92.5%), while the P type was successfully determined in 35 (87.5%) of the 40 (24%) page positive samples. Type G1 was the most predominant of the G types (40.5%), and the incidences of G3 and G9 were 21.6 and 32.4% respectively. Mixed types G3/G9 were detected at 5.4%. Three P types existed in Mukuru slums, P[8] (60%), P[6] (22.9%), P[4] (11.4) and their relative incidence varied over the 15 months of this study. Conclusions The G types and P types detected in this study are important causes of acute gastroenteritis in Mukuru slums Nairobi Kenya. An indication that the prevalence of certain genotypes may change over a rotavirus season is significant and mirrors observations from studies in other tropical climates. Thus monitoring of the genotypic changes among circulating viruses should be encouraged over the coming years

Risk factors for diarrheagenic Escherichia coli infection in children aged 6-24 months in peri-urban community, Nairobi, Kenya

Escherichia coli commonly inhabits the gut of humans and animals as part of their microbiota. Though mostly innocuous, some strains have virulence markers that make them pathogenic. This paper presents results of a cross-sectional epidemiological study examining prevalence of diarrheagenic E. coli (DEC) pathotypes in stool samples of asymptomatic healthy children (n = 540) in Dagoretti South subcounty, Nairobi, Kenya. E. coli was cultured and pathotyped using PCR to target specific virulence markers associated with Shiga-toxin, enteropathogenic, enterotoxigenic, enteroaggregative, entero-invasive and diffusely adherent E. coli. Overall prevalence of DEC pathotypes was 20.9% (113/540) with enteropathogenic E. coli being the most prevalent (34.1%), followed by enteroaggregative E. coli (23.5%) and Shiga-toxin producing E. coli (22.0%) among positive samples. We found evidence of co-infection with multiple pathotypes in 15% of the positive samples. Our models indicated that at the household level, carriage of DEC pathotypes in children was associated with age group [12-18 months] (OR 1.78; 95%CI 1.03-3.07; p = 0.04), eating matoke (mashed bananas) (OR 2.32; 95%CI 1.44-3.73; p = 0.001) and pulses/legumes (OR 1.74; 95%CI 1.01-2.99; p = 0.046) while livestock ownership or contact showed no significant association with DEC carriage (p>0.05). Our findings revealed significant prevalence of pathogenic DEC circulating among presumptive healthy children in the community. Since there has been no previous evidence of an association between any food type and DEC carriage, unhygienic handling, and preparation of matoke and pulses/legumes could be the reason for significant association with DEC carriage. Children 12-18 months old are more prone to DEC infections due to exploration and hand-to-mouth behavior. A detailed understanding is required on what proportion of positive cases developed severe symptomatology as well as fatal outcomes. The co-infection of pathotypes in the rapidly urbanizing environment needs to be investigated for hybrid or hetero-pathotype circulation that have been implicated in previous infection outbreaks