39 research outputs found
Molecular Cloning and Expression of a Thermostable Α-Amylase from Geobacillus Sp.
Starch degrading enzymes like amylase have received great deal of attention
because of their perceived technological significance and economic benefits.
Selection of a suitable strain is the most significant factor in the amylase
production process. On the other hand the screening for a single amylase is
difficult because one strain can produce different amylases with different
specificities or the amount of amylase produced may be very low. Thus the
cloning of one gene directing the synthesis of the desired amylase in a well
characterized host like E. coli should help greatly in the characterization of new
amylases and also allow a significant yield increase. Studies on the screening of
amylase producing bacterial strains were carried out on soil and water samples
collected from a hot spring located in Slim River, Perak, Malaysia. The bacteria
were cultivated in a mineral medium containing soluble starch as the sole carbon
source. Three of the isolates namely SR37, SR41, SR74 have demonstrated good
activity based on the assay performed using DNS method at 60oC and pH 7.0. The isolates showed activity of 2.44 U/ml, 4.5 U/ml, 2.05 U/ml for amylopectin and
1.78 U/ml, 3.54 U/ml, 1.65 U/ml for soluble starch, respectively. None of the
isolates except SR74 (1.65 U/ml) showed activity at 70oC. Since it showed
activity at 70oC, further study was conducted on the isolate SR74 for
identification, gene cloning, sequencing and expression for the α-amylase enzyme.
Gram staining and morphological studies revealed the isolate was a Gram positive
Bacillus. Molecular characterization using the 16S rDNA for the isolate SR74
revealed the organism closely related to the members of the genus Geobacillus.
The fatty acid methyl ester analysis using the Sherlock system also resulted in a
typical fatty acid profile of a thermophilic Geobacillus and other bacilli. Among
them the iso-branched pentadecanoic acid (iso-15:0), haxadecanoic acid (iso-16:0)
and heptadecanoic acids ( iso-17:0) accounted for 82.26% of the total fatty
acids.Iso-15:0 and iso-17:0 were especially abundant. This isolate exhibited
anteiso-15:0 (1.05%) and anteiso-17:0 (6.5%) as minor components (7.55% of the
total). The isolate was identified as Geobacillus sp. SR74. The gene coding for a
thermostable α-amylase from Geobacillus sp. SR74 was isolated, sequenced and
expressed in Escherichia coli BL21 (DE3) pLysS. Gene sequencing showed that
the enzyme secreted by this isolate shared 98% similarity with Geobacillus
stearothermophilus α-amylase gene. The ORF of the gene codes for 549 amino
acids. The signal peptide comprised 34 amino acids and the remaining 515 amino
acids belong to the mature polypeptide. The region encoding the mature α-
amylase was heterogeneously expressed in E. coli BL21 (DE3) pLysS cells using
the pET-32b expression system under the control of the T7 promoter. The mature
enzyme had a theoretical molecular weight of 58,547 Daltons and a theoretical pI
of 5.61. Optimization studies revealed that the highest enzyme activity was obtained at 16h post induction (32.414 U/ml). The optimum inducer concentration
was found to be 0.15mMol L-1 IPTG (39.73 U/ml). With regard to production
media, LB (49.53 U/ml) and 0.75YT (51.06 U/ml) were found to be best for
optimum production of the recombinant enzyme, while the A600nm of 0.75 (58.3
U/ml) being the best microbial density for inducing the production of the enzyme
Maternal death review: a path to achieve the Millennium Development Goal of improving maternal health
No Abstract
Determinants and outcomes of disclosing HIV-sero positive status to sexual partners among women in Mettu and Gore towns, Illubabor Zone southwest Ethiopia
Background: Disclosing one's HIV test result to a sexual partner is an important factor in HIV/AIDS prevention interventions. Disclosure of one's HIV status enables for improved access to prevention and treatment programs provides increased opportunities for risk reduction and helps in planning for the future. An assessment of the barriers and outcomes for disclosure is necessary to enhance HIV test result disclosure among couples.
Objective: This study is aimed at determining the rate, barriers and out comes of HIV positive status disclosure among sexual partners.
Method: A cross sectional study was conducted in Mettu and Gore towns of Illubabor Zone, south west Ethiopia. Sixty-seven women living with HIV out of which 42(62.7%) reported to had sexual partners and were eligible for the study and were interviewed. A structured questionnaire was used for data collection.
Results: Overall 69% of the women reported that they had shared their HIV test results with their partners. Among the women who did not disclose their HIV status 62.5% said that it was due to fear of partner’s reaction (fear of abandonment, rejection and accusation of infidelity). But 75.9 % of HIV positive women who disclosed their result reported positive partner’s reaction. Most (81.3%) women who had prior discussion about HIV and HIV testing with their partners have disclosed their results (P<0.005). Condom use was also found to be high among couples that disclosed their HIV/status than those who did not do so (P<0.05).
Conclusion: This study indicates that the outcomes of disclosure are encouraging. The anticipated partner reactions and the reality discovered by the study were different. Therefore it is important to assure HIV-positive women that the benefits of disclosure out weigh the potential risks. A large-scale study on the subject is also recommended
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Uptake and barriers of voluntary counseling and testing among antenatal care attendants, southwest Ethiopia
BACKGROUND . Voluntary counseling and testing (VCT) service provides an essential knowledge, skill and helps pregnant women to access intervention such as short course antiretroviral and infant feeding options. Therefore, the potential barriers to the service need to be assessed.
OBJECTIVE: This study is intended to examine the uptake of VCT and its barrier among Antenatal care (ANC) attendants in southwest Ethiopia.
METHODS- Health institution based cross-sectional study was conducted from Sept. 1. 2004 to Nov. 1, 2004 a mong ANC attendants in southwest Ethiopia. A total of 285 pregnant women were selected conveniently. Additionally, five experienced counselors were involved in the study. Both qualitative and quantitative interviews methods were utilized using structured questionnaires.
RESULT-Out of a total of 285 pregnant women who participated in the study, 77(27% had decepted VCT. The acceptance rate was higher among 16-20 years old women (p<0.05) and those from urban résidences (p<0.025). Women who are single, divorced or widowed were also found to have more acceptance of VCT than married women (P<0.001). Among tested women 61(79.2%) received test result. Qualitative analysis showed that I ack of decision-making a utonomy and fear of partner's reactions were identified as major barriers. The reason for low return for test result was the women do not want to know their HIV status; but gave their blood to avoid offending the counselors.
CONCLUSION - This study revealed that the uptake of VCT service is very low. Therefore, to increase the utilization of VCT service at ANC setting, problems associated with the service should be addressed. This includes quality of counseling, provision of test result on same day and addressing individual concerns
A historical overview of traditional medicine practices and policy in Ethiopia
Abstract Background: Although traditional medicine plays an important role in Ethiopian society, knowledge about the extent and characteristics of traditional healing practices and practitioners is limited and has frequently been ignored in the national health system. Objective: To review history of practices and policies on traditional medicine in Ethiopia. Methods: A systematic review of available literature on Ethiopian traditional medicine and policy documents was carried out. Google, Pub Med and Medline online internet searches were done to access relevant material. In addition, materials from Jimma University Library and the Ethiopian Federal Ministry of Health Library were used. Several authorities were also contacted to supplement the literature. Result: There are a number of traditional medicinal practices that reflect the diversity of Ethiopian cultures. Ethiopian traditional medicine is concerned not only with the curing of diseases but also with the protection and promotion of human physical, spiritual, social, mental and material wellbeing. The many categories of traditional medicinal practices dealing with these different aspects of health include: spiritual healing, prevention, as well as curative and surgical practices. The health and drug policies of the Ethiopian Ministry of Health recognize the important role traditional health systems play in health care. Unfortunately, little has been done in recent decades to enhance and develop the beneficial aspects of traditional medicine including relevant research to explore possibilities for its gradual integration into modern medicine. Conclusion: The Ethiopian government firmly supports and encourages traditional medicine through its policies as part of the national heritage. Despite these commitments on the policies, the government's ability to implement and provide increased resources for the study, as well as sustainable use of traditional medicine and their integration with modern medical practice has been limited. Introduction The World Health Organization (WHO) defines traditional medicine as health practices, approaches, knowledge and beliefs incorporating plant, animal and mineral based medicines, spiritual therapies, manual techniques and exercises, applied singularly or in combination to treat, diagnose and prevent illnesses and maintain well-being (1)
Estimating the burden of mycetoma in Sudan for the period 1991-2018 using a model-based geostatistical approach
Mycetoma is widespread in tropical and subtropical regions favouring arid areas with low humidity and a short rainy season. Sudan is one of the highly endemic countries for mycetoma. Estimating the population at risk and the number of cases is critical for delivering targeted and equitable prevention and treatment services. In this study, we have combined a large dataset of mycetoma cases recorded by the Mycetoma Research Centre (MRC) in Sudan over 28 years (1991-2018) with a collection of environmental and water and hygiene-related datasets in a geostatistical framework to produce estimates of the disease burden across the country. We developed geostatistical models to predict the number of cases of actinomycetoma and eumycetoma in areas considered environmentally suitable for the two mycetoma forms. Then used the raster dataset (gridded map) with the population estimates for 2020 to compute the potentially affected population since 1991. The geostatistical models confirmed this heterogeneous and distinct distribution of the estimated cases of eumycetoma and actinomycetoma across Sudan. For eumycetoma, these higher-risk areas were smaller and scattered across Al Jazirah, Khartoum, White Nile and Sennar states, while for actinomycetoma a higher risk for infection is shown across the rural districts of North and West Kurdufan. Nationally, we estimated 63,825 people (95%CI: 13,693 to 197,369) to have been suffering from mycetoma since 1991 in Sudan,51,541 people (95%CI: 9,893 – 166,073) with eumycetoma and 12,284 people (95%CI: 3,800 – 31,296) with actinomycetoma. In conclusion, the risk of mycetoma in Sudan is particularly high in certain restricted areas, but cases are ubiquitous across all states. Both prevention and treatment services are required to address the burden. Such work provides a guide for future control and prevention programs for mycetoma, highly endemic areas are clearly targeted, and resources are directed to areas with high demand
Substance use and its predictors among undergraduate medical students of Addis Ababa University in Ethiopia
<p>Abstract</p> <p>Background</p> <p>Substance use remains high among Ethiopian youth and young adolescents particularly in high schools and colleges. The use of alcohol, <it>khat </it>and tobacco by college and university students can be harmful; leading to decreased academic performance, increased risk of contracting HIV and other sexually transmitted diseases. However, the magnitude of substance use and the factors associated with it has not been investigated among medical students in the country. This study was conducted to determine the prevalence of substance use and identify factors that influenced the behavior among undergraduate medical students of Addis Ababa University in Ethiopia.</p> <p>Methods</p> <p>A cross-sectional study using a pre-tested structured self-administered quantitative questionnaire was conducted in June 2009 among 622 medical students (Year I to Internship program) at the School of Medicine. The data were entered into Epi Info version 6.04d and analyzed using SPSS version 15 software program. Descriptive statistics were used for data summarization and presentation. Differences in proportions were compared for significance using Chi Square test, with significance level set at p < 0.05. Multivariate logistic regression analyses were used to assess the magnitude of associations between substance use and socio-demographic and behavioral correlates.</p> <p>Results</p> <p>In the last 12 months, alcohol was consumed by 22% (25% males vs. 14% females, p = 0.002) and <it>khat </it>use was reported by 7% (9% males vs. 1.5% females, p < 0.001) of the students. About 9% of the respondents (10.6% males vs. 4.6% females, p = 0.014) reported ever use of cigarette smoking, and 1.8% were found to be current smokers. Using multiple logistic regression models, being male was strongly associated with alcohol use in the last 12 months (adjusted OR = 2.14, 95% CI = 1.22-3.76). Students whose friends currently consume alcohol were more likely to consume alcohol (adjusted OR = 2.47, 95% CI = 1.50-4.08) and whose friends' use tobacco more likely to smoke (adjusted OR = 3.89, 95% CI = 1.83-8.30). <it>Khat </it>use within the past 12 months was strongly and positively associated with alcohol consumption (adjusted OR = 15.11, 95% CI = 4.24-53.91). Similarly, ever use of cigarette was also significantly associated with alcohol consumption (adjusted OR = 8.65, 95% CI = 3.48-21.50).</p> <p>Conclusions</p> <p>Concordant use of alcohol, <it>khat </it>and tobacco is observed and exposure to friends' use of substances is often implicated. Alcohol consumption or <it>khat </it>use has been significantly associated with tobacco use. While the findings of this study suggest that substance use among the medical students was not alarming, but its trend increased among students from Year I to Internship program. The university must be vigilant in monitoring and educating the students about the consequences of substance use.</p
Traditional values of virginity and sexual behaviour in rural Ethiopian youth: results from a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Delaying sexual initiation has been promoted as one of the methods of decreasing risks of HIV among young people. In traditional countries, such as Ethiopia, retaining virginity until marriage is the norm. However, no one has examined the impact of this traditional norm on sexual behaviour and risk of HIV in marriage. This study examined the effect of virginity norm on having sex before marriage and sexual behaviour after marriage among rural Ethiopian youth.</p> <p>Methods</p> <p>We did a cross-sectional survey in 9 rural and 1 urban area using a probabilistic sample of 3,743 youth, 15–24 years of age. Univariate analysis was used to assess associations between virginity norm and gender stratified by area, and between sexual behaviour and marital status. We applied Kaplan-Meier and Cox regression analysis to estimate age at sexual debut and assessed the predictors of premarital sex among the never-married using SPSS.</p> <p>Results</p> <p>We found that maintaining virginity is still a way of securing marriage for girls, especially in rural areas; the odds of belief and intention to marry a virgin among boys was 3–4 times higher among rural young males. As age increased, the likelihood of remaining a virgin decreased. There was no significant difference between married and unmarried young people in terms of number of partners and visiting commercial sex workers. Married men were twice more likely to have multiple sexual partners than their female counterparts. A Cox regression show that those who did not believe in traditional values of preserving virginity (adjusted hazard ratio [AHR] = 2.91 [1.92–4.40]), alcohol drinkers (AHR = 2.91 [1.97–4.29]), Khat chewers (AHR = 2.36 [1.45–3.85]), literates (AHR = 18.01 [4.34–74.42]), and the older age group (AHR = 1.85 [1.19–2.91]) were more likely to have premarital sex than their counterparts.</p> <p>Conclusion</p> <p>Although virginity norms help delay age at sexual debut among rural Ethiopian youth, and thus reduces vulnerability to sexually transmitted infections and HIV infection, vulnerability among females may increase after marriage due to unprotected multiple risky sexual behaviours by spouses. The use of preventive services, such as VCT before marriage and condom use in marriage should be part of the HIV/AIDS prevention and control strategies.</p
Disclosure experience and associated factors among HIV positive men and women clinical service users in southwest Ethiopia
BACKGROUND: Disclosing HIV test results to one's sexual partner allows the partner to engage in preventive behaviors as well as the access of necessary support for coping with serostatus or illness. It may motivate partners to seek testing or change behavior, and ultimately decrease the transmission of HIV. The present study was undertaken to determine the rate, outcomes and factors associated with HIV positive status disclosure in Southwest Ethiopia among HIV positive service users. METHODS: A cross-sectional study was carried out from January 15, 2007 to March 15, 2007 in Jimma University Specialized Hospital. Data were collected using a pre-tested interviewer-administered structured questionnaire. RESULTS: A total of 705 people (353 women and 352 men), participated in the study of which 71.6% were taking ART. The vast majority (94.5%) disclosed their result to at least one person and 90.8% disclosed to their current main partner. However, 14.2% of disclosure was delayed and 20.6% did not know their partner's HIV status. Among those who did not disclose, 54% stated their reason as fear of negative reaction from their partner. Among those disclosures however, only 5% reported any negative reaction from the partner. Most (80.3%) reported that their partners reacted supportively to disclosure of HIV status. Disclosure of HIV results to a sexual partner was associated with knowing the partner's HIV status, advanced disease stage, low negative self-image, residing in the same house with partner, and discussion about HIV testing prior to seeking services. CONCLUSION: Although the majority of participants disclosed their test results, lack of disclosure by a minority resulted in a limited ability to engage in preventive behaviors and to access support. In addition, a considerable proportion of the participants did not know their partner's HIV status. Programmatic and counseling efforts should focus on mutual disclosure of HIV test results, by encouraging individuals to ask their partner's HIV status in addition to disclosing their own