The long-term impact of the MEMA kwa Vijana adolescent sexual and reproductive health intervention: effect of dose and time since intervention exposure

Background

Despite recent decreases in HIV incidence in many sub-Saharan African countries, there is little evidence that specific behavioural interventions have led to a reduction in HIV among young people. Further and wider-scale decreases in HIV require better understanding of when behaviour change occurs and why. The MEMA kwa Vijana adolescent sexual and reproductive health intervention has been implemented in rural Mwanza, Tanzania since 1999. A long-term evaluation in 2007/8 found that the intervention improved knowledge, attitudes to sex and some reported risk behaviours, but not HIV or HSV2 prevalence. The aim of this paper was to assess the differential impact of the intervention according to gender, age, marital status, number of years of exposure and time since last exposure to the intervention.

Methods

In 2007, a cross-sectional survey was conducted in the 20 trial communities among 13,814 young people (15–30 yrs) who had attended intervention or comparison schools between 1999 and 2002. Outcomes for which the intervention had an impact in 2001 or 2007 were included in this subgroup analysis. Data were analysed using cluster-level methods for stratified cluster-randomised trials, using interaction tests to determine if intervention impact differed by subgroup.

Results

Taking into account multiplicity of testing, concurrence with a priori hypotheses and consistency within the results no strong effect-modifiers emerged. Impact on pregnancy knowledge and reported attitudes to sex increased with years of exposure to high-quality intervention.

Conclusions

The desirable long-term impact of the MEMA kwa Vijana intervention did not vary greatly according to the subgroups examined. This suggests that the intervention can have an impact on a broad cross-section of young people in rural Mwanza.

Trial registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00248469","term_id":"NCT00248469"}}NCT00248469     

Long-Range Surface Plasmon Supported by Asymmetric Bimetallic Structure

With this study, we prove that an asymmetric bimetallic structure can support long-range surface plasmon (LRSP) and propose a procedure for its optimization. By applying different criteria we prove that the plasmon which is supported by the structure is indeed LRSP. Unlike all known asymmetric structures supporting LRSP, our structure provides prism excitation and can be used as a biochip for biosensing. Moreover, we show that the structure supports a plasmon with the same propagation constant as LRSP and which is excited at the interface of metal and buffer. This plasmon can be used as a reference channel providing information for the temperature of the structure.     

Enhanced Defence Responses of Chickpea Plants Against Rhizoctonia solani by Pre‐Inoculation with Rhizobia

The aim of this work was to study the antagonist effect of two Rhizobium strains Pch Azm and Pch S.Nsir2 to Rhizoctonia solani and for an evaluation of the relative impact of rhizobia on the expression of the plant's defence response against Rhizoctonia. First, these strains reduced fungal growth observed in vitro using the same or separately Petri dishes. Moreover, these isolates led to reduced chickpea infection by R. solani, resulting from the direct effect of rhizobia on pathogens and possible induced resistance in chickpea. Concomitantly, reduction in infection was accompanied by enhanced level of defence‐related enzymes, phenylalanine ammonia lyase (PAL) and peroxidase (POX). An increased level of phenol content was recorded in the roots of bacterized plants grown in the presence of pathogen. The results promise the use of rhizobia for protection of chickpea against R. solani.     

Effect of a normal protein diet on oxidative stress and organ damage in malnourished rats

Background

We investigated the effects of three weeks of renutrition with a normal protein diet on oxidant/antioxidant status in malnourished rats using biochemistry and histology.

Methods

Eighteen young Wistar rats were divided into three groups: control group was fed on a normal protein diet; malnourished group was fed on low protein diet and renourished group was fed on low protein diet followed by a normal protein diet. Serum albumin was evaluated. Malondialdehyde, protein carbonyl, superoxide dismutase and catalase levels were determined in the intestine, muscle and liver. Intestinal and hepatic damage were assessed by histological examination.

Results

Protein malnutrition resulted in a significant decrease of body weight, albumin level, villus length, intraepithelial lymphocytes counts (IELC) and superoxide dismutase level (liver and muscle). However, catalase activity increased significantly in muscle and gut but there was no difference in liver. In all organs, malondialdehyde and protein carbonyl content of malnourished group showed a significant increase. Interestingly, a normal protein diet for three weeks resulted in a return to normal levels of superoxide dismutase, albumin, malondialdehyde and protein carbonyl in all organs. Catalase activity decreased in the muscle and gut and exhibited no significant difference in the liver. The renutrition diet enhanced also the recovery of intestinal epithelium by increasing villus length. Hepatic damage of rats fed normal protein diet was markedly reduced (macrovesicular steatosis decreased by 45%).

Conclusion

The normal protein diet could improve the oxidant/antioxidant imbalance and organ damage induced by protein malnutrition.

     

Proved viraemia in asian influenza (Hong Kong variant) during incubation period

During an outbreak of influenza specimens were obtained from 21 patients with influenza-like illnesses and from 29 healthy subjects in close contact with the patients. Throat washings from 12 of the patients were positive for influenza virus but virus was not detected from the blood specimens. One healthy contact became ill 12 hours after the specimens were obtained, and the virus was isolated from his blood and throat washings. The remaining contacts showed no clinical illness; but the virus was isolated from the throat washings of four of them, with no viral isolation from the blood specimens.     

Vaginal Practices among Women at High Risk of HIV Infection in Uganda and Tanzania: Recorded Behaviour from a Daily Pictorial Diary

Background

Intravaginal practices (IVP) are highly prevalent in sub-Saharan African and have been implicated as risk factors for HIV acquisition. However, types of IVP vary between populations, and detailed information on IVP among women at risk for HIV in different populations is needed. We investigated IVP among women who practice transactional sex in two populations: semi-urban, facility workers in Tanzania who engage in opportunistic sex work; and urban, self-identified sex workers and bar workers in Uganda. The aim of the study was to describe and compare IVP using a daily pictorial diary.

Methodology/Principal Findings

Two hundred women were recruited from a HIV prevention intervention feasibility study in Kampala, Uganda and in North-West Tanzania. Women were given diaries to record IVP daily for six weeks. Baseline data showed that Ugandan participants had more lifetime partners and transactional sex than Tanzanian participants. Results from the diary showed that 96% of Tanzanian participants and 100% of Ugandan participants reported intravaginal cleansing during the six week study period. The most common types of cleansing were with water only or water and soap. In both countries, intravaginal insertion (e.g. with herbs) was less common than cleansing, but insertion was practiced by more participants in Uganda (46%) than in Tanzania (10%). In Uganda, participants also reported more frequent sex, and more insertion related to sex. In both populations, cleansing was more often reported on days with reported sex and during menstruation, and in Uganda, when participants experienced vaginal discomfort. Participants were more likely to cleanse after sex if they reported no condom use.

Conclusions

While intravaginal cleansing was commonly practiced in both cohorts, there was higher frequency of cleansing and insertion in Uganda. Differences in IVP were likely to reflect differences in sexual behaviour between populations, and may warrant different approaches to interventions targeting IVP. Vaginal practices among women at high risk in Uganda and Tanzania: recorded behaviour from a daily pictorial diary.     

HIV Infection among Young People in Northwest Tanzania: The Role of Biological,Behavioural and Socio-Demographic Risk Factors

Background

Young people are at high risk of HIV and developing appropriate prevention programmes requires an understanding of the risk factors for HIV in this age group. We investigated factors associated with HIV among participants aged 15–30 years in a 2007–8 cross-sectional survey nested within a community-randomised trial of the MEMA kwa Vijana intervention in 20 rural communities in northwest Tanzania.

Methods

We analysed data for 7259(53%) males and 6476(47%) females. Using a proximate-determinant conceptual framework and conditional logistic regression, we obtained sex-specific Odds Ratios (ORs) for the association of HIV infection with socio-demographic, knowledge, behavioural and biological factors.

Results

HSV-2 infection was strongly associated with HIV infection (females: adjOR 4.4, 95%CI 3.2–6.1; males: adjOR 4.2, 95%CI 2.8–6.2). Several socio-demographic factors (such as age, marital status and mobility), behavioural factors (condom use, number and type of sexual partnerships) and biological factors (blood transfusion, lifetime pregnancies, genital ulcers, Neisseria gonorrhoeae) were also associated with HIV infection. Among females, lifetime sexual partners (linear trend, p<0.001), ≥2 partners in the past year (adjOR 2.0, 95%CI 1.4–2.8), ≥2 new partners in the past year (adjOR 1.9 95%CI 1.2, 3.3) and concurrent partners in the past year (adjOR 1.6 95%CI 1.1, 2.4) were all associated with HIV infection.

Conclusions

Efforts must be intensified to find effective interventions to reduce HSV-2. Effective behavioural interventions focusing on reducing the number of sexual partnerships and risk behaviour within partnerships are also needed. An increase in risky sexual behaviour may occur following marriage dissolution or when a young woman travels outside of her community and interventions addressing the needs of these subgroups of vulnerable women may be important.

Trial Registration

ClinicalTrial.gov {"type":"clinical-trial","attrs":{"text":"NCT00248469","term_id":"NCT00248469"}}NCT00248469.     

Sulfur bacteria in wastewater stabilization ponds periodically affected by the ‘red-water’ phenomenon

Several wastewater stabilization ponds (WSP) in Tunisia suffer periodically from the ‘red-water’ phenomenon due to blooming of purple sulfur bacteria, indicating that sulfur cycle is one of the main element cycles in these ponds. In this study, we investigated the microbial diversity of the El Menzeh WSP and focused in particular on the different functional groups of sulfur bacteria. For this purpose, we used denaturing gradient gel electrophoresis of PCR-amplified fragments of the 16S rRNA gene and of different functional genes involved in microbial sulfur metabolism (dsrB, aprA, and pufM). Analyses of the 16S rRNA revealed a relatively high microbial diversity where Proteobacteria, Chlorobi, Bacteroidetes, and Cyanobacteria constitute the major bacterial groups. The dsrB and aprA gene analysis revealed the presence of deltaproteobacterial sulfate-reducing bacteria (i.e., Desulfobacter and Desulfobulbus), while the analysis of 16S rRNA, aprA, and pufM genes assigned the sulfur-oxidizing bacteria community to the photosynthetic representatives belonging to the Chlorobi (green sulfur bacteria) and the Proteobacteria (purple sulfur and non sulfur bacteria) phyla. These results point on the diversity of the metabolic processes within this wastewater plant and/or the availability of sulfate and diverse electron donors.