Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo

Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible.     

The Dissipation of Carbofuran in Two Soils with Different Pesticide Application Histories within Nzoia River Drainage Basin,Kenya

The dissipation of carbofuran from soils within the Nzoia River Drainage Basin in Kenya was studied under real field conditions for 112 days. Results showed significantly enhanced dissipation of carbofuran with half life (DT₅₀) values of 8 days (p = 0.038) in soils with prior exposure to carbofuran compared to 19 days in soils with no application history. At the end of the experiment, residues of 2.57 % and 9.36 % of the initial carbofuran applied were recorded in the two types of soil, respectively. Carbofuran metabolites identified in the study were 3-keto carbofuran and carbofuran phenol with 5.84 % and 15.0 % remaining in soils with prior exposure, respectively. Soils with no application history recorded 16.05 % and 12.82 % of 3-keto carbofuran and carbofuran phenol metabolites, respectively.     

A randomized open label clinical trial to compare the efficacy and safety of intravenous quinine followed by oral malarone vs. intravenous quinine followed by oral quinine in the treatment of severe malaria

The treatment of patients with severe malaria in sub-Saharan Africa has become a challenge to clinicians due to poor compliance to quinine and the increasing multidrug resistance to antimalarials by the P. falciparum parasite. The aim of this study was to compare the efficacy and safety profile of two truncated antimalarial regimens of intravenous quinine followed by oral Malarone (Malarone arm) with intravenous quinine followed by oral quinine (quinine arm) in the treatment of severe P. falciparum malaria. The outcome measures were parasite clearance time, fever clearance time, efficacy, and adverse events profile. Consecutive patients aged 1-60 years, with a diagnosis of severe malaria with positive blood smears for P. falciparum parasites and admitted to the Moi Teaching and Referral Hospital were randomized into the two study arms. Of the 360 patients studied 167 and 193 cases were randomized into the Malarone and quinine arms, respectively. Of the five (1.4 per cent) patients who died, three came from the quinine arm. The frequency of adverse reactions was higher in the oral quinine group (31.6 per cent) than in the Malarone group (25.7 per cent). The mean parasite clearance time was 120 h and 108 h for the quinine and Malarone arms of the study, respectively, and the mean fever clearance times were 84 h and 72 h for the quinine and Malarone arms, respectively (p=0.1). Truncated therapeutic regimen using malarone after intravenous quinine is safer and as effective as conventional intravenous quinine followed by oral quinine in the treatment of severe malaria. The P. falciparum recrudescence rate was lower with the use of Malarone than for quinine.     

KEMRI Hep-cell II hepatitis B surface antigen screening kit

Kenya is a high hepatitis B virus endemic zone, and prevention of viral transmission by transfusing safe blood is necessary. However, kits for screening hepatitis B surface antigen (HBsAg) are usually imported and are expensive; hence, it has been difficult to screen donated and patient blood samples all over the country. This laboratory-based study, conducted at the Kenya Medical Research Institute (KEMRI), produced a HBsAg screening kit locally in order to be able to screen donated and patient blood samples throughout Kenya. Purified HBsAg from plasma carriers obtained from the National Public Health Laboratories Services was used to induce guinea pigs to produce anti-hepatitis B antibody (anti-HBs). The anti-HBs was then used to sensitize sheep red blood cells. The final product was freeze dried (lyophilized) and its sensitivity and specificity was compared with other commercial kits. The KEMRI Hep-cell II had 98% and 99% sensitivity and specificity, respectively, in comparison with other commercial kits. The kit was found to be stable and potent for 1 year at temperatures of 4 degrees Celsius, 37 degrees Celsius, or at room temperature. The KEMRI Hep-cell II kit is cheap and affordable and requires a simple apparatus to carry out the test; hence, it can be used anywhere in Kenya.     

Loss to follow-up among youth accessing outpatient HIV care and treatment services in Kisumu,Kenya

Youth are particularly vulnerable to acquiring HIV, yet reaching them with HIV prevention interventions and engaging and retaining those infected in care and treatment remains a challenge. We sought to determine the incidence rate of loss to follow-up (LTFU) and explore socio-demographic and clinical characteristics associated with LTFU among HIV-positive youth aged 15–21 years accessing outpatient care and treatment clinics in Kisumu, Kenya. Between July 2007 and September 2010, youth were enrolled into two different HIV care and treatment clinics, one youth specific and the other family oriented. An individual was defined as LTFU when absent from the HIV treatment clinic for ≥?4 months regardless of their antiretroviral treatment status. The incidence rate of LTFU was calculated and Cox regression analysis used to identify factors associated with LTFU. A total of 924 youth (79% female) were enrolled, with a median age of 20 years (IQR 18–21). Over half, (529 (57%)), were documented as LTFU, of whom 139 (26%) were LTFU immediately after enrolment. The overall incidence rate of LTFU was 52.9 per 100 person-years (p-y). Factors associated with LTFU were pregnancy during the study period (crude HR 0.68, 95% CI 0.53–0.89); CD4 cell count >350 (adjusted hazard ratios (AHR) 0.59, 95% CI 0.39–0.90); not being on antiretroviral therapy (AHR 4.0, 95% CI 2.70–5.88); and non-disclosure of HIV infection status (AHR 1.43, 95% CI 1.10–1.89). The clinic of enrolment, age, marital status, employment status, WHO clinical disease stage and education level were not associated with LTFU. Interventions to identify and enrol youth into care earlier, support disclosure, and initiate ART earlier may improve retention of youth and need further investigation. Further research is also needed to explore the reasons for LTFU from care among HIV-infected youth and the true outcomes of these patients.