Neuropeptide precursors in Tribolium castaneum

Neuropeptides and neurohormones are among the more diverse and functionally important classes of cell-to-cell signaling molecules involved in animal development and behavior. Less is known about the hormones and neuropeptides of the red flour beetle, Tribolium castaneum, than many other insects. However, the genomic information becoming available from this organism presents an opportunity to identify multiple neuropeptide and hormone genes, and hence their associated protein precursors. Using similarity-based prediction, we report new neuropeptides and hormone precursors from T. castaneum, bringing the number of annotated precursors to 37. We identified one prohormone (SVDPIDGDLIG-containing) having little similarity to other insect prohormones. The conversion of the protein precursors into bioactive peptides requires a suite of processing enzymes and a number of enzymatic steps; using the web-based NeuroPred application and similarity-based bioinformatics approaches, we predict 132 likely peptides that may result from the enzymatic processing of these gene products.     

Bridging neuropeptidomics and genomics with bioinformatics: Prediction of mammalian neuropeptide prohormone processing

Neuropeptides are an important class of cell to cell signaling molecules that are difficult to predict from genetic information because of their large number of post-translational modifications. The transition from prohormone genetic sequence information to the determination of the biologically active neuropeptides requires the identification of the cleaved basic sites, among the many possible cleavage sites, that exist in the prohormone. We report a binary logistic regression model trained on mammalian prohormones that is more sensitive than existing methods in predicting these processing sites, and demonstrate the application of this method to mammalian neuropeptidomic studies. By comparing the predictive abilities of a binary logistic model trained on molluscan prohormone cleavages with the reported model, we establish the need for phyla-specific models.     

Efect of emergency oral contraceptive use on condom utilization and sexual risk taking behaviours among university students, Northwest Ethiopia: a cross-sectional study

ABSTRACT: BACKGROUND: Young people between the ages of 15 and 24 years are both the most at risk of HIV and the greatest hope for turning the tide against HIV/AIDS. Although various surveys have been done on sexual behaviour of youth in Ethiopia, studies assessing the effect of emergency oral contraceptives on condom utilization of university students are lacking. METHODS: A cross-sectional study was conducted in two major universities of Ethiopia from January to May 2011 using structured self administered questionnaire with the aim to assess the effect of introducing oral emergency contraceptive pills on condom utilization and sexual risk taking behaviours among female university students. Study participants were selected by simple random sampling using the list from the associate registrars of each University. Data were entered, cleaned and analyzed using SPSS version 17.0. Bivariate and multiple logistic regression analyses were used to determine factors associated with condom utilization. RESULTS: a total of 623 students out of 660 were included giving response rate of 94.4%. A total of 103(16.5%) had history of sexual intercourse and nearly half (45.6%) of them had sex before the age of 20 years. Forty (6.4%) students had history of sexually transmitted infections (STI). Sixty seven percent of students had heard about emergency oral contraceptives. One hundred and ninety one (45.7%) of students believe that EOC is effective in preventing pregnancy. Believing that EOC is effective in preventing pregnancy (adjusted Odds ratio, AOR = 0.22 95% CI 0.06, 0.87), condom prevents STI (AOR = 10.37, 95%CI 1.73, 62.24) and younger age below 20 years (AOR = 11.68 95% CI 1.25, 109.19) were statistically significantly associated with condom use. CONCLUSION: a significant number of students had history of sexual intercourse and used emergency contraception. The belief in the effectiveness of EOC negatively affects condom use. The preference for the pill may make teenagers less prepared to practice STI protective behaviours in specific situations. Therefore, there is an urgent need to educate young people in universities about reproductive health and family planning and skills on how to prevent HIV/STIs including unwanted pregnancy.     

Field-based investigation on phytoremediation potentials of Lemna minor and Azolla filiculoides in tropical,semiarid regions: Case of Ethiopia

This study investigated the concurrent accumulation of eight heavy metals by two floating aquatic macrophytes (Lemna minor and Azolla filiculoides) cultivated in ambient media and blended wastewaters in the semiarid regions of Ethiopia. Both species accumulated heavy metals in varying degrees with a significant concentration gradient within the immediate water media. Highest bioconcentration factor (BCF) was determined for Mn and Fe in both plants. Results revealed that L. minor was high phytoaccumulator for Fe, Mn, Zn, and Co but moderate for Cd, Cu, Ni, and Cr. On the other hand, A. filiculoides was a high accumulator for Fe, Mn, Zn, and Cu, but its potency was moderate for Co, Cr, and Ni, but lower for Cd. Both species exhibited significant difference in accumulating Co, Zn, and Mn (p < 0.05). In general, the BCFs for both plants were comparable within the same treatment. In this study, stronger associations between the heavy metal concentrations in the plant tissues and in the grown water media were observed for A. filiculoides.     

Production of alkaline protease by an alkaliphilic bacteria isolated from an alkaline soda lake

A new alkaliphilic strain of Microbacterium producing an alkaline protease was isolated from an alkaline soda lake in Ethiopia. High level of protease activity was produced in the presence of glucose and sucrose as carbon sources. The optimum temperature and pH for activity were 65°C and 9.5-11.5 respectively. Above 50°C, Ca²⁺ was required for enzyme activity and stability. At 55 and 60°C it retained 100 and 85% of its original activity respectively after 1 h incubation. The enzyme was stable over the pH range of 5-12. This revised version was published online in November 2006 with corrections to the Cover Date.     

Exclusive breastfeeding status of children aged between 6 and 24 months in the nomadic population of Hadaleala district,Afar Region,northeast Ethiopia

Background

Exclusive breastfeeding (EBF) during infancy is fundamental, however it is not fully practiced in the nomadic population of Ethiopia. In Ethiopia, there is still a lack of information on the implementation of the EBF, especially among the nomadic population. This study was conducted to assess the EBF status of children during their first 6 months of life, who are now aged between 6 and 24 months, in the nomadic population of Afar region. The study also aimed to identify factors affecting exclusive breastfeeding.

Methods

A community based cross-sectional study was conducted from April to May, 2015 to assess EBF of children aged between 6 and 24 months during the first 6 months of life. Exclusive breastfeeding is defined as consuming only breast milk (including expressed breast milk) during the first 6 months and no other liquids and solid foods except medications, and non exclusive breastfeeding is taking liquids and solid foods in addition to breast milk. The cluster sampling technique was used to select the study participants. Data were collected from 254 households using a structured questionnaire.

Results

One hundred eighty eight of the children were fed breast milk exclusively for the first 6 months of age; the rate of EBF in the study area was 74% (95% CI 70, 78%). One hundred fifty four (60.6%) of the children received breast milk within 1 h immediately after birth and 207 (81.5%) of the children maintained breastfeeding at the time of the survey. Exclusive breastfeeding was statistically associated with mothers aged above 35 years (AOR 8.3, 95% CI 1.7, 40.3), commencing to breastfeed in first hour (AOR 3.5, 95% CI 1.8, 6.9), and parents who didn’t migrate or move to a more comfortable area (AOR 4.6, 95% CI 1.5, 14.4).

Conclusion

Exclusive breastfeeding was not fully practiced in the study area. Therefore, promotion of infant and young children feeding (IYCF) is needed in the area to strengthen EBF practices. Moreover, child feeding practices should be integrated with the existing health system and attention should be given to the nomadic mothers.