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Screening with portable echocardiography has uncovered a large burden of latent rheumatic heart disease (RHD) among asymptomatic children in endemic regions, the significance of which remains unclear. This study aimed to determine the 2-year outcomes for children with latent RHD diagnosed by echocardiographic screening. Children identified with latent RHD enrolled in a biannual follow-up program. Risk factors for disease persistence and progression were examined. Of 62 children, 51 (82 %) with latent RHD had a median follow-up period of 25 months. Of these 51 children, 17 (33.3 %) reported an interval sore throat or symptoms consistent with acute rheumatic fever (ARF). Of 43 children initially classified as having borderline RHD, 21 (49 %) remained stable, 18 (42 %) improved (to no RHD) and 4 (10 %) worsened to definite RHD. Of the 8 children initially classified as having definite RHD, 6 (75 %) remained stable, and 2 (25 %) improved to borderline RHD. Two children had confirmed episodes of recurrent ARF, one of which represented the sole case of clinical worsening. The risk factors for disease persistence or progression included younger age (p = 0.05), higher antistreptolysin O titers at diagnosis (p = 0.05), and more morphologic valve abnormalities (p = 0.01). After 2 years, most of the children had a benign course, with 91 % remaining stable or showing improvement. Education may improve recognition of streptococcal sore throat. Longer-term follow-up evaluation, however, is warranted to confirm disease progression and risk factor profile. This could help tailor screening protocols for those at highest risk.  相似文献   
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A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
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This study was undertaken to measure and compare the thickness and cross-sectional area of the Achilles tendon between frequent- and infrequent-exercise subjects, and between the dominant and nondominant ankles in an asymptomatic Chinese population. Interobserver variability in the measurement of the size of Achilles tendon was also evaluated. High-resolution ultrasound (US) examination of Achilles tendons was performed in 40 healthy subjects (20 who frequently exercised, had exercise at least 3 days per week and at least 2 h per session; and 20 who infrequently exercised); their age range was 19 to 25 years. The thickness and cross-sectional area of the Achilles tendons were measured in a transverse scan at the level of medial malleolus. For each subject, the Achilles tendons were measured by five operators to evaluate the interobserver variability in the measurements. The mean thickness and cross-sectional areas of the Achilles tendon in a healthy Chinese population are 5.23 mm(2) and 56.91 mm(2)(2), respectively. The mean thickness of the Achilles tendon of frequent-exercise subjects (dominant ankle 5.43 mm, nondominant ankle 5.38 mm) was significantly greater than that of infrequent-exercise subjects (dominant ankle 5.08 mm, nondominant ankle 5.04 mm) (p < 0.05). The cross-sectional area of the tendons was also larger in frequent-exercise subjects but, whereas a significant result was found in dominant ankles (frequent-exercise subjects 60.46 mm(2)(2), infrequent-exercise subjects 54.71 mm(2)(2)) (p < 0.05), this was not the case for the nondominant ankles (frequent-exercise subjects 57.09 mm(2)(2), infrequent-exercise subjects 55.4 mm(2)(2)) (p > 0.05). In both frequent- and infrequent-exercise subjects, there was no significant difference in the mean thickness and cross-sectional area of Achilles tendon between dominant and nondominant ankles (p > 0.05). There was a high reproducibility in the sonographic measurement of the thickness (68%) and cross-sectional area (81%) of Achilles tendons. Results suggested that exercise would cause increase in the thickness and cross-sectional area of Achilles tendon. Interobserver variability is not significant in the sonographic measurement of Achilles tendons.  相似文献   
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IntroductionAs they grow, young people transit through adolescence; a particularly challenging phase. Many go through without difficulties but some experience maladaptive responses in form of conduct and adjustment problems, pubertal challenges and life stress. Published research from the developed societies demonstrates consistent associations between young people''s exposure to life events, psychosocial competence (PSC) and mental health problems. However, comparable research from income-constrained societies remains scarce. The purpose of this study was to determine the prevalence of life events in secondary school students and describe the relationship between life events and PSC in the same population.MethodsThis was a cross-sectional study. Participants were 2,902 randomly selected in Central and Northern Uganda. They responded to self-administered questionnaires on socio-demographics, life events and PSC.ResultsNorthern Ugandan students were more likely to be susceptible to stress-related illness associated with major life events (p = < 0.01). Among students with a high susceptibility to stress related illness, those with low scores on self-efficacy (p = < 0.001), accurate self-assessment (p = < 0.001) and self-confidence (p = < 0.001) were mostly from the North. Students from Northern Uganda had experienced more negative events. Students with higher scores on empathy, emotional awareness, accurate self- assessment and self-confidence tended to have low distress. Students that had a low susceptibility to stress related illness (AOR = 1.97; 95% CI: 1.57 – 2.48); high scores on self-efficacy (AOR 1.37; 95% CI: 1.09 – 1.74), self-confidence (AOR 1.32; 95% CI: 1.02 – 1.72), and accurate self-assessment (AOR 2.19; 95% CI: 1.70 – 2.80) were mostly from northern Uganda.ConclusionIt is important to help students to cope with negative life events since an association exists between negative life events and PSC domains. PSC domains of empathy, emotional awareness, accurate self-assessment and self-confidence seem to be associated with lower distress levels, implying that these should be reinforced.  相似文献   
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Background

The relationship between war-related trauma exposure, depressive symptoms and multiple risk behaviors among adolescents is less clear in sub-Saharan Africa.

Methods

We analyzed data collected from a sample of school-going adolescents four years postwar. Participants completed interviews assessing various risk behaviors defined by the Youth Self Report (YSR) and a sexual risk behavior survey, and were screened for post-traumatic stress, anxiety and depression symptoms based on the Impact of Events Scale Revised (IESR) and Hopkins Symptom Checklist for Adolescents (HSCL-37A) respectively. Multivariate logistic regression was used to assess factors independently associated with multiple risk behaviors. The logistic regression model of Baron and Kenny (1986) was used to evaluate the mediating role of depression in the relationship between stressful war events and multiple risk behaviors.

Results

Of 551 participants, 139 (25%) reported multiple (three or more) risk behaviors in the past year. In the multivariate analyses, depression symptoms remained uniquely associated with multiple risk behavior after adjusting for potential confounders including socio-demographic characteristics, war-related trauma exposure variables, anxiety and post-traumatic stress symptoms. In mediation analysis, depression symptoms mediated the associations between stressful war events and multiple risk behaviors.

Limitations

The psychometric properties of the questionnaires used in this study are not well established in war affected African samples thus ethno cultural variation may decrease the validity of our measures.

Conclusions

Adolescents with depression may be at a greater risk of increased engagement in multiple risk behaviors. Culturally sensitive and integrated interventions to treat and prevent depression among adolescents in post-conflict settings are urgently needed.  相似文献   
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Immune activation is thought to play a major role in the pathogenesis of human immunodeficiency virus (HIV). This effect may be particularly relevant in Africa, where endemic coinfections may contribute to disease progression, perhaps as a consequence of enhanced immune activation. We investigated the expression of CD38 and human leukocyte antigen (HLA)-DR on T cells in 168 HIV-seropositive volunteers in Uganda. We observed higher levels of CD4(+) and CD8(+) T cell activation in Uganda, compared with those reported in previous studies from Western countries. Coexpression of CD38 and HLA-DR on both CD4(+) and CD8(+) T cell subsets was directly correlated with viral load and inversely correlated with CD4(+) T cell counts. In antiretroviral therapy (ART)-naive volunteers, viral load and CD4(+) T cell count had stronger associations with CD8(+) and CD4(+) T cell activation, respectively. Virus suppression by ART was associated with a reduction in T cell activation, with a stronger observed effect on reducing CD8(+) compared with CD4(+) T cell activation. The presence of coinfection was associated with increased CD4(+) T cell activation but, interestingly, not with increased CD8(+) T cell activation. Our results suggest that distinct mechanisms differentially drive activation in CD4(+) and CD8(+) T cell subsets, which may impact the clinical prognostic values of T cell activation in HIV infection.  相似文献   
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