126 research outputs found
Hair Bundle Morphology on Surviving Hair Cells of the Chick Basilar Papilla Exposed to Intense Sound
Exposure to intense sound produces a well-defined patch lesion on the chick basilar papilla in which 30-35% of the short hair cells are lost. The present study compares various aspects of sensory hair bundle morphology on surviving hair cells in the patch lesion with hair bundles from matched locations on nonexposed control papilla immediately after removal from the exposure and 12-days post exposure. The height and thickness of the hairs, the total number of hairs in the bundle, the width of the bundle, and the area and perimeter of the apical surface of the hair cell were quantified from scanning electron microscope photomicrographs. An attempt was also made to determine if there was a consistent microstructure to the pattern of hair cell loss within the lesion area. Similar observations in 12-day recovered ears are also presented.
The results indicated that stereocilia height increased and width decreased on surviving hair cells in the exposed ear. The width of the hair bundle, the hair cell surface area, and perimeter also decreased. However, the number of hairs per cell remained unchanged, and there was no evidence of any consistent organization to the hair cell loss within the patch across a number of specimens. These observations indicated that the hair bundles on short hair cells underwent changes as a consequence of intense sound exposure.The results after 12 days of recovery were complicated by developmental changes on the papilla and incomplete maturation of the newly regenerated hair cells. It remains to be seen whether these changes were the result of cell sampling in the sound-damaged ear or were due to true structural alterations within the sensory hairs themselves
Effects of guanidine on synaptic transmission in the spinal cord of the frog
The effects of guanidine on motoneurons of the isolated frog spinal cord were studied by adding the drug to the solution bathing the cord during intracellular recording. Guanidine (5·10–4 M) did not alter the membrane potential of motoneurons.
The main effect was a marked increase of the amplitudes and frequencies of small spontaneously occurring inhibitory postsynaptic potentials. The hyperpolarizing component of postsynaptic potentials evoked by stimulation of dorsal roots was also enhanced by guanidine. Higher concentrations of guanidine (5·10–3 M) resulted in a very large and irreversible increase of the small spontaneously occurring inhibitory potentials, which now appeared in a regular, rhythmic pattern.
The effects of guanidine could easily be blocked by increasing the magnesium ions (15 mM) in the bath solution.
These results indicate that guanidine facilitates the release of an inhibitory transmitter in afferent terminals of the frog spinal cord either by a direct action on these terminals or indirectly by an action on nerve endings impinging on inhibitory interneurons
The association between family and community social capital and health risk behaviours in young people: an integrative review
Background:
Health risk behaviours known to result in poorer outcomes in adulthood are generally established in late childhood and adolescence. These ‘risky’ behaviours include smoking, alcohol and illicit drug use and sexual risk taking. While the role of social capital in the establishment of health risk behaviours in young people has been explored, to date, no attempt has been made to consolidate the evidence in the form of a review. Thus, this integrative review was undertaken to identify and synthesise research findings on the role and impact of family and community social capital on health risk behaviours in young people and provide a consolidated evidence base to inform multi-sectorial policy and practice.<p></p>
Methods:
Key electronic databases were searched (i.e. ASSIA, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Embase, Medline, PsycINFO, Sociological Abstracts) for relevant studies and this was complemented by hand searching. Inclusion/exclusion criteria were applied and data was extracted from the included studies. Heterogeneity in study design and the outcomes assessed precluded meta-analysis/meta-synthesis; the results are therefore presented in narrative form.<p></p>
Results:
Thirty-four papers satisfied the review inclusion criteria; most were cross-sectional surveys. The majority of the studies were conducted in North America (n=25), with three being conducted in the UK. Sample sizes ranged from 61 to 98,340. The synthesised evidence demonstrates that social capital is an important construct for understanding the establishment of health risk behaviours in young people. The different elements of family and community social capital varied in terms of their saliency within each behavioural domain, with positive parent–child relations, parental monitoring, religiosity and school quality being particularly important in reducing risk.<p></p>
Conclusions:
This review is the first to systematically synthesise research findings about the association between social capital and health risk behaviours in young people. While providing evidence that may inform the development of interventions framed around social capital, the review also highlights key areas where further research is required to provide a fuller account of the nature and role of social capital in influencing the uptake of health risk behaviours.<p></p>
"I will not let my HIV status stand in the way." Decisions on motherhood among women on ART in a slum in Kenya- a qualitative study
Impact of financial inclusion in low- and middle-income countries: a systematic review of reviews
Financial inclusion programmes seek to increase access to financial services such as credit, savings, insurance and money transfers and so allow poor and low-income households in low- and middle-income countries to enhance their welfare, grasp opportunities, mitigate shocks, and ultimately escape poverty. This systematic review of reviews assesses the evidence on economic, social, behavioural and gender-related outcomes from financial inclusion. It collects and appraises all of the existing meta-studies - that is systematic reviews and meta-analyses - of the impact of financial inclusion. The authors first analyse the strength of the methods used in those meta-studies, then synthesise the findings from those that are of a sufficient quality, and finally, report the implications for policy, programming, practice and further research arising from the evidence. Eleven studies are included in the analysis
Poverty and Wellbeing Impacts of Microfinance : What Do We Know?
Over the last 35 years, microfinance has been generally regarded as an effective policy tool in the fight against poverty. Yet, the question of whether access to credit leads to poverty reduction and improved wellbeing remains open. To address this question, we conduct a systematic review of the quantitative literature of microfinance’s impacts in the developing world, and develop a theory of change that links inputs to impacts on several welfare outcomes. Overall, we find that the limited comparability of outcomes and the heterogeneity of microfinance-lending technologies, together with a considerable variation in socio-economic conditions and contexts in which impact studies have been conducted, render the interpretation and generalization of findings intricate. Our results indicate that, at best, microfinance induces short-term dynamism in the financial life of the poor; however, we do not find compelling evidence that this dynamism leads to increases in income, consumption, human capital and assets, and, ultimately, a reduction in poverty
Oral and anal sex practices among high school youth in Addis Ababa, Ethiopia
<p>Abstract</p> <p>Background</p> <p>Understanding the full range of sexual behaviors of young people is crucial in developing appropriate interventions to prevent and control sexually transmitted infections including HIV. However, such information is meager in developing countries. The objective of this study was to describe oral and anal sex practices and identify associated factors among high school youth.</p> <p>Methods</p> <p>A cross-sectional study was conducted among high school youth in Addis Ababa, Ethiopia. A multi-stage sampling procedure was followed to select a representative sample of school youth. The total sample size for this study was 3840. Data were collected using a self-administered questionnaire. Data analysis was guided by the ecological framework.</p> <p>Results</p> <p>The overall proportion of people who reported ever having oral sex was 5.4% (190) and that of anal sex was 4.3% (154). Of these 51.6% (98) had oral sex and 57.1% (87) had anal sex in the past 12 months. Multiple partnerships were reported by 61.2% of the respondents who had oral sex and 51.1% of students practicing anal sex. Consistent condom use was reported by 12.2% of those practicing oral sex and 26.1% of anal sex. Reasons for oral and anal sex included prevention of pregnancy, preserving virginity, and reduction of HIV and STIs transmission. Oral sex practice was strongly and significantly associated with perception of best friends engagement in oral sex (AOR = 5.7; 95% CI 3.6-11.2) and having illiterate mothers (AOR = 11.5; 95%CI 6.4-18.5). Similarly, anal sex practice was strongly and significantly associated with favorable attitude towards anal sex (AOR = 6.2; 95%CI 3.8-12.4), and perceived best friends engagement in anal sex (AOR = 9.7; 95%CI 5.4-17.7).</p> <p>Conclusion</p> <p>Considerable proportion of adolescents had engaged in oral and anal sex practices. Multiple sexual partnerships were common while consistent condom use was low. Sexual health education and behavior change communication strategies need to cover a full range of sexual practices.</p
Coping strategies of women with postpartum depression symptoms in rural Ethiopia: a cross-sectional community study
Background:
Most women with postpartum depression (PPD) in low- and middle-income countries remain undiagnosed and untreated, despite evidence for adverse effects on the woman and her child. The aim of this study was to identify the coping strategies used by women with PPD symptoms in rural Ethiopia to inform the development of socio-culturally appropriate interventions.
Methods:
A population-based, cross-sectional study was conducted in a predominantly rural district in southern Ethiopia.
All women with live infants between one and 12 months post-partum (n = 3147) were screened for depression symptoms using the validated Patient Health Questionnaire, 9 item version (PHQ-9). Those scoring five or more, ‘high PPD
symptoms’, (n = 385) were included in this study. The Brief Coping with Problems Experienced (COPE-28) scale was used
to assess coping strategies. Construct validity of the brief COPE was evaluated using confirmatory factor analysis.
Results:
Confirmatory factor analysis of the brief COPE scale supported the previously hypothesized three dimensions of
coping (problem-focused, emotion-focused, and dysfunctional). Emotion-focused coping was the most commonly employed coping strategy by women with PPD symptoms. Urban residence was associated positively with all three dimensions of coping. Women who had attended formal education and who attributed their symptoms to a physical cause were more likely to use both problem-focused and emotion-focused coping strategies. Women with better subjective wealth and those who perceived that their husband drank too much alcohol were more likely to use emotion-focused coping. Dysfunctional coping strategies were reported by women who had a poor relationship with their husbands.
Conclusions:
As in high-income countries, women with PPD symptoms were most likely to use emotion-focused and dysfunctional coping strategies. Poverty and the low level of awareness of depression as an illness may additionally impede problem-solving attempts to cope. Prospective studies are needed to understand the prognostic significance of coping styles in this setting and to inform psychosocial intervention development
Sexual practices among unmarried adolescents in Tanzania
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Sexual activities are increasingly changing from the cultural point of view what they used to be. Knowledge of these practices among adolescents may be a basis to create awareness among adolescents on practices that involve risks. This study aims to assess sexual practices among unmarried adolescents in Tanzania. A cross-sectional survey was conducted among in-school and out-of-school but unmarried adolescents aged 10 to 19 in five locations in Tanzania. A questionnaire was used to collect information and to characterize sexual practices among these adolescents. About 32% of adolescents reported being sexually active; a higher proportion being males than females. The only inquired and reported sexual practices include vaginal sex, masturbation, oral and anal sex. About 15% of sexually active adolescents reported having multiple sexual partners. Significantly more males reported having multiple partners than females. Nearly 42% of sexually active adolescents reported having used a condom during most recent sexual act. Females reported older partners at first sexual act. Adolescents experience several sexual practices that include penetrative and non-penetrative. More males reported being sexually active than females. Despite adolescents reporting having multiple sexual partners, reported condom use during the most recent sexual act was low. We advocate for a more enhanced approach of reproductive health education that includes safer sex to adolescents without forgetting those in-schools.\u
Porn video shows, local brew, and transactional sex: HIV risk among youth in Kisumu, Kenya
Background: Kisumu has shown a rising HIV prevalence over the past sentinel surveillance surveys, and most new infections are occurring among youth. We conducted a qualitative study to explore risk situations that can explain the high HIV prevalence among youth in Kisumu town, Kenya
Methods: We conducted in-depth interviews with 150 adolescents aged 15 to 20, held 4 focus group discussions, and made 48 observations at places where youth spend their free time.
Results: Porn video shows and local brew dens were identified as popular events where unprotected multipartner, concurrent, coerced and transactional sex occurs between adolescents. Video halls - rooms with a TV and VCR - often show pornography at night for a very small fee, and minors are allowed. Forced sex, gang rape and multiple concurrent relationships characterised the sexual encounters of youth, frequently facilitated by the abuse of alcohol, which is available for minors at low cost in local brew dens. For many sexually active girls, their vulnerability to STI/HIV infection is enhanced due to financial inequality, gender-related power difference and cultural norms. The desire for love and sexual pleasure also contributed to their multiple concurrent partnerships. A substantial number of girls and young women engaged in transactional sex, often with much older working partners. These partners had a stronger socio-economic position than young women, enabling them to use money/gifts as leverage for sex. Condom use was irregular during all types of sexual encounters.
Conclusions: In Kisumu, local brew dens and porn video halls facilitate risky sexual encounters between youth. These places should be regulated and monitored by the government. Our study strongly points to female vulnerabilities and the role of men in perpetuating the local epidemic. Young men should be targeted in prevention activities, to change their attitudes related to power and control in relationships. Girls should be empowered how to negotiate safe sex, and their poverty should be addressed through income-generating activities.</p
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