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1.
Mutations in the photoreceptor cell-specific nuclear receptor gene Nr2e3 increased the number of S-cone photoreceptors in human and murine retinas and led to retinal degeneration that involved photoreceptor and non-photoreceptor cells. The mechanisms underlying these complex phenotypes remain unclear. In the hope of understanding the precise role of Nr2e3 in photoreceptor cell fate determination and differentiation, we generated a line of Nr2e3 knockout zebrafish using CRISPR technology. In these Nr2e3-null animals, rod precursors undergo terminal mitoses but fail to differentiate as rods. Rod-specific genes are not expressed and the outer segment (OS) fails to form. Formation and differentiation of cone photoreceptors is normal. Specifically, there is no increase in the number of UV-cone or S-cone photoreceptors. Laminated retinal structure is maintained. After normal development, L-/M-cones selectively degenerate, with progressive shortening of OS that starts at age 1 month. The amount of cone phototransduction proteins is concomitantly reduced, whereas UV- and S-cones have normal OS lengths even at age 10 months. In vitro studies show Nr2e3 synergizes with Crx and Nrl to enhance rhodopsin gene expression. Nr2e3 does not affect cone opsin expression. Our results extend the knowledge of Nr2e3's roles and have specific implications for the interpretation of the phenotypes observed in human and murine retinas. Furthermore, our model may offer new opportunities in finding treatments for enhanced S-cone syndrome (ESCS) and other retinal degenerative diseases.  相似文献   
2.

Background

Tuberculosis (TB) is among the leading causes of morbidity and mortality worldwide. More than 70% of the deaths of TB patients occur during the first two months of TB treatment. The major risk factors that increase early death of TB patients are being positive for human immunodeficiency virus (HIV), being of old age, being underweight or undergoing re-treatment.

Objective

To assess the time of reported deaths and associated factors in a cohort of patients with TB during TB treatment.

Methods

An institution-based retrospective cohort study was analyzed in Dangila Woreda, Northwest Ethiopia from March 1st through March 30, 2014. All TB patients registered in the direct observed treatment (DOTs) clinic from 2008–2012 were included in the study. Data were entered into EpiData and exported to SPSS for analysis. The survival probability was analyzed by the Kaplan Meier method and Cox regression analysis was applied to investigate factors associated with death during TB treatment.

Results

From a total of 872 cases registered in TB registry log book, 810 were used for the analysis of which 60 (7.4%) died during the treatment. The overall mortality rate was 12.8/1000 person months of observation. A majority of TB deaths 34 (56.7%) occurred during the intensive phase of the treatment, and the median time of death was at two months of the treatment. Age, HIV status and baseline body weight were independent predictors of death during TB treatment.

Conclusions

Most deaths occurred in the first two months of TB treatment. Old age, TB/HIV co-infection and a baseline body weight of <35 kg increased the mortality during TB treatment. Therefore, a special follow up of TB patients during the intensive phase, of older patients and of TB/HIV co-infected cases, as well as nutritionally supplementing for underweight patients may be important to consider as interventions to reduce deaths during TB treatment.  相似文献   
3.
Objective: To contrast relief efforts for the 26 December 2004 tsunami with current global HIV/AIDS relief efforts and analyse possible reasons for the disparity. Methods: Literature review and ethical analysis. Results: Just over 273,000 people died in the tsunami, resulting in relief efforts of more than US$10 bn, which is sufficient to achieve the United Nation’s long‐term recovery plan for South East Asia. In contrast, 14 times more people died from HIV/AIDS in 2004, with UNAIDS predicting a US$8 bn funding gap for HIV/AIDS in developing nations between now and 2007. This disparity raises two important ethical questions. First, what is it that motivates a more empathic response to the victims of the tsunami than to those affected by HIV/AIDS? Second, is there a morally relevant difference between the two tragedies that justifies the difference in the international response? The principle of justice requires that two cases similarly situated be treated similarly. For the difference in the international response to the tsunami and HIV/AIDS to be justified, the tragedies have to be shown to be dissimilar in some relevant respect. Are the tragedies of the tsunami disaster and the HIV/AIDS pandemic sufficiently different, in relevant respects, to justify the difference in scope of the response by the international community? Conclusion: We detected no morally relevant distinction between the tsunami and the HIV/AIDS pandemic that justifies the disparity. Therefore, we must conclude that the international response to HIV/AIDS violates the fundamental principles of justice and fairness.  相似文献   
4.
5.

Background

To assess and compare the prevalence, severity and prognosis of anti-TB drug induced hepatotoxicity (DIH) in HIV positive and HIV negative tuberculosis (TB) patients in Ethiopia.

Methodology/Principal Findings

In this study, 103 HIV positive and 94 HIV negative TB patients were enrolled. All patients were evaluated for different risk factors and monitored biochemically and clinically for development of DIH. Sub-clinical hepatotoxicity was observed in 17.3% of the patients and 8 out of the 197 (4.1%) developed clinical hepatotoxicity. Seven of the 8 were HIV positive and 2 were positive for HBsAg.

Conclusions/Significance

Sub-clinical hepatotoxicity was significantly associated with HIV co-infection (p = 0.002), concomitant drug intake (p = 0.008), and decrease in CD4 count (p = 0.001). Stepwise restarting of anti TB treatment was also successful in almost all the patients who developed clinical DIH. We therefore conclude that anti-TB DIH is a major problem in HIV-associated TB with a decline in immune status and that there is a need for a regular biochemical and clinical follow up for those patients who are at risk.  相似文献   
6.
7.

Background

Assessment of delays in seeking care and diagnosis of tuberculosis is essential to evaluate effectiveness of tuberculosis control programs, and identify programmatic impediments. Thus, this review of studies aimed to examine the extent of patient, health system, and total delays in diagnosis of pulmonary tuberculosis in low- and middle- income countries.

Methods

It was done following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Electronic databases were searched to retrieve studies published from 2007 to 2015 including Pubmed central, Springer link, Hinari and Google scholar. Searching terms were pulmonary tuberculosis, health care seeking, health care seeking behavior, patient delay, diagnostic delay, health system delay, provider delay, and doctor delay. Retrieved studies were systematically reviewed and summarized using Comprehensive Meta-analysis software.

Results

Forty studies involving 18,975 patients qualified for systematic review, and 14 of them qualified for meta-analysis. The median diagnostic delay ranged from 30 to 366.5 days [IQR?=?44–77.8], with a 4–199 days [IQR?=?15–50] and 2–128.5 days [IQR?=?12–34] due to patient and health system delays, respectively. The meta-analysis showed 42% of pulmonary tuberculosis patients delayed seeking care by a month or more; uneducated patients [pooled OR?=?1.5, 95%CI?=?1.1–1.9] and those who sought initial care from informal providers [pooled OR?=?3, 95%CI?=?2.3–3.9] had higher odds of patient delay.

Conclusion

Delay in diagnosis is still a major challenge of tuberculosis control and prevention programs in low- and middle- income settings. Efforts to develop new strategies for better case-finding using the existing systems and improving patients’ care seeking behavior need to be intensified.
  相似文献   
8.
The tapertail anchovy Coilia brachygnathus, a commercially important species mainly distributed along the mid-lower Chang-Jiang basin, is by far the most dominant species in Lake Honghu. To figure out its success in this semiclosed lake, some basic biological parameters of this anchovy were analysed based on samples seasonally collected from October 2020 to December 2021. The results demonstrated that the age classes of fished individuals varied from 0.5 to 3.5, with the majority (97.36%) being between 0.5 and 3 years old. The size at 50% maturity of 17.2 cm total length (TL) for females and 19.0 cm TL for males corresponded to 1 and 1.6 years, respectively. Coilia brachygnathus has a short life span, early sexual maturity and a relatively fast growth rate. The flourishing of the fish in the lake is mainly attributed to its short life span, early maturity, fast growth rate, closed fishing, pelagic spawners, the availability of plenty of food and low predation effect on it. Age 3.5 year occurs in an extremely small percentage of the total (<3%), indicating that a large number of larger-sized or older fish died after spawning, which is probably one of the major sources of water pollution if the closed fishing measure is adopted in Lake Honghu. Thus, individuals older than 2 years or more than 20.0 cm TL should be harvested. These findings have important management implications for the fish resources in Lake Honghu and beyond.  相似文献   
9.

Background

Despite the benefits of childhood vaccinations, vaccination rates in low-income countries (LICs) vary widely. Increasing coverage of vaccines to 90% in the poorest countries over the next 10 years has been estimated to prevent 426 million cases of illness and avert nearly 6.4 million childhood deaths worldwide. Consequently, we sought to provide a comprehensive examination of contemporary vaccination patterns in East Africa and to identify common and country-specific barriers to complete childhood vaccination.

Methods

Using data from the Demographic and Health Surveys (DHS) for Burundi, Ethiopia, Kenya, Rwanda, Tanzania, and Uganda, we looked at the prevalence of complete vaccination for polio, measles, Bacillus Calmette–Guérin (BCG) and DTwPHibHep (DTP) as recommended by the WHO among children ages 12 to 23 months. We conducted multivariable logistic regression within each country to estimate associations between complete vaccination status and health care access and sociodemographic variables using backwards stepwise regression.

Results

Vaccination varied significantly by country. In all countries, the majority of children received at least one dose of a WHO recommended vaccine; however, in Ethiopia, Tanzania, and Uganda less than 50% of children received a complete schedule of recommended vaccines. Being delivered in a public or private institution compared with being delivered at home was associated with increased odds of complete vaccination status. Sociodemographic covariates were not consistently associated with complete vaccination status across countries.

Conclusions

Although no consistent set of predictors accounted for complete vaccination status, we observed differences based on region and the location of delivery. These differences point to the need to examine the historical, political, and economic context of each country in order to maximize vaccination coverage. Vaccination against these childhood diseases is a critical step towards reaching the Millennium Development Goal of reducing under-five mortality by two-thirds by 2015 and thus should be a global priority.  相似文献   
10.
BackgroundPodoconiosis is preventable if genetically susceptible people wear shoes starting from an early age and do so consistently. However, lack of routine use of footwear is one of the major risk factors for podoconiosis and several other foot-related Neglected Tropical Diseases (NTDs). This study is aimed at describing the extent of footwear use among school-age rural children susceptible to the disease and investigating associated socioeconomic factors.MethodsCross sectional surveys were conducted in 330 randomly selected households in Wolaita zone, southern Ethiopia. A household head and a child aged between 9 and 15 years were recruited from each household. Household heads provided socioeconomic data while children were asked about their footwear ownership and footwear use.ResultsNearly half (49.5%) of the children reported either walking barefoot or wearing under-protective footwear in a range of situations. Girls, older children, those in higher school grades, who belonged to families with higher socio-economic status, and those who owned a larger number of pairs of footwear reported more protective use of footwear. The linear regression model constituting the adequacy of footwear ownership and interaction term (i.e. family socioeconomic status by adequacy of footwear ownership) variables explained 30% of variance in the protective use of footwear (AR2 = 0.307). The interaction effect of adequate ownership of footwear and family socioeconomic status consistently predicted the protective use of footwear among children (β = -0.175, p<0.01) though the main effect of adequacy of footwear ownership was stronger (β = 0.507, p<0.001).ConclusionIncreased adoption of protective footwear is needed to effectively prevent school-age children living in endemic areas from developing podoconiosis and other neglected tropical diseases. Interventions aimed to improve the protective footwear use should consider approaches that also increase the socio-economic capacity of families in podoconiosis endemic communities.  相似文献   
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