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111.
OBJECTIVE: To assess the burden of respiratory syncytial virus (RSV)-associated lower respiratory infections (LRI) in children in four developing countries. METHODS: A WHO protocol for prospective population-based surveillance of acute respiratory infections in children aged less than 5 years was used at sites in Indonesia, Mozambique, Nigeria and South Africa. RSV antigen was identified by enzyme-linked immunosorbent assay performed on nasopharyngeal specimens from children meeting clinical case definitions. FINDINGS: Among children aged < 5 years, the incidence of RSV-associated LRI per 1000 child-years was 34 in Indonesia and 94 in Nigeria. The incidence of RSV-associated severe LRI per 1000 child-years was 5 in Mozambique, 10 in Indonesia, and 9 in South Africa. At all study sites, the majority of RSV cases occurred in infants. CONCLUSION: These studies demonstrate that RSV contributes to a substantial but quite variable burden of LRI in children aged < 5 years in four developing countries. The possible explanations for this variation include social factors, such as family size and patterns of seeking health care; the proportion of children infected by human immunodeficiency syndrome (HIV); and differences in clinical definitions used for obtaining samples. The age distribution of cases indicates the need for an RSV vaccine that can protect children early in life.  相似文献   
112.
Experimental transmission of Trichomonas vaginalis into laboratory was carried out. The protein and glucose levels of infected vaginal exudates were also investigated. Subcutaneous lesions were produced in the mice with influx of neutrophils and macrophages and sloughing of epidermal parts. Rats, seem to be refractory to this infection. Compared with normal persons, the protein and glucose levels were higher and richer in exudates of patients with T. vaginalis infection.  相似文献   
113.
114.
The isolation of 98/ASF/NG, a strain of African Swine Fever Virus (ASFV) associated with a 1998 epizootic in Nigeria, is reported. This first isolate of the virus from West Africa was identified through a successful polymerase chain reaction (PCR) amplification and sequencing of a 280 base pair (bp) fragment of the Major Capsid Protein (VP72) gene. Further amplification and sequence analysis of a 1.9 kilobase pair (kbp) fragment encompassing the complete VP72 gene showed that the isolate has a 92.2%, 92.4%, and 97.2% homology with previously sequenced Ugandan, Dominican Republican and Spanish isolates respectively. Of the 50 nucleotide changes observed in this highly conserved gene, 45 were found to result in 40 amino acid changes clustered around the central region (position 426 to 516) of the VP 72 protein while changes at the remaining 5 positions were silent. These changes also led to the loss of two out of the seven potential N-glycosylation sites which are in this gene conserved among all isolates. The possible epizootiological implications of such mutations in a highly conserved gene of a DNA virus is discussed in relation to this outbreak.  相似文献   
115.
Protection against cardiomyocyte damage following ischemia/reperfusion (I/R) injury is highly desirable in patients with ischemic heart disease. Hydromethanol extracts of Globimetula cupulata (mistletoe) growing on cocoa (CGCE) and kola nut (KGCE) trees were assessed for antioxidant content and cardioprotective potential against I/R. Graded concentrations (1–50 μg/mL) of CGCE or KGCE were tested on Langendorff-perfused rat hearts to evaluate the effects on the flow rate, heart rate, and force of cardiac contraction, while another set of hearts were subjected to biochemical analyses. Both extracts showed good antioxidant content and activity, but KGCE (EC50: 24.8±1.8 μg/mL) showed higher hydroxyl radical scavenging activity than CGCE (70.2±4.5 μg/mL). Both extracts at 3 μg/mL reversed (p < 0.001) membrane peroxidation and the significant decrease in nitrite level, coronary flow rate, and superoxide dismutase and catalase activity caused by the I/R cycle. It is concluded that G. cupulata protects against ischemia–reperfusion injury in rat hearts via augmenting endogenous antioxidants and significant restoration of altered hemodynamic parameters.  相似文献   
116.
Introduction: The clinical and public health implications of the convergence of the human immunodeficiency virus (HIV) epidemic and chronic viral hepatitis in sub-Saharan Africa are poorly understood. This study was designed to determine the seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV), and the impact of co-infection on baseline serum alanine transaminase (ALT), CD4+ T lymphocyte (CD4) count, and plasma HIV-RNA (viral load) in a cohort of HIV-infected Nigerians. Methods: A retrospective study was conducted, on eligible treatment-naive patients who presented between August 2004 and February 2007 to the University College Hospital (UCH), Ibadan, Nigeria. Demographic data and pre-treatment laboratory results (hepatitis B surface antigen (HBsAg), HCV antibodies (anti-HCV), ALT, CD4 count and viral load) were retrieved from the medical records. Fisher’s exact, two sample t-tests, and the Wilcoxon rank sum tests were used to compare groups. A logistic regression model was fitted to explore characteristics associated with co-infection status. Results: A total of 1779 HIV-infected patients (male: female ratio, 1:2) met inclusion criteria. HBsAg was present in 11.9%, anti-HCV in 4.8% and both markers in 1%. HBsAg was more common among males than females (15.4% vs 10.1%, respectively p = 0.001) while anti-HCV was detected in a similar proportion of males and females (5.3% versus 4.6%, respectively p = 0.559). HIV-infected patients with anti-HCV alone had a lower mean baseline CD4 count compared to those without anti-HCV or HBsAg (197 cells/mm3vs247 cells/mm3, respectively p = 0.008). Serum ALT was higher among patients with HBsAg compared to those without HBsAg or anti-HCV (43 International Units (IU) vs. 39 IU, respectively p = 0.015). Male gender was associated with HBV co-infection on logistic regression (OR1.786; 95% CI, 1.306-2.443; p < 0.005). Conclusion: More HIV-infected females than males presented for care in this cohort. We identified a relatively high prevalence of HBV and HCV co-infection in general, and a higher rate of HBV co-infection among males than females. Pre-treatment CD4 count was significantly lower among those with HCV co-infection, while ALT was slightly higher among those with HBV co-infection. Triple infection with HIV, HBV and HCV was present in a small but significant proportion of patients. These findings underscore the importance of testing for HBV and HCV in all HIV-infected persons in our setting.  相似文献   
117.
Carpal tunnel syndrome in patients with diabetic polyneuropathy   总被引:4,自引:0,他引:4  
OBJECTIVE: Carpal tunnel syndrome (CTS) and diabetic polyneuropathy (DPN) are common conditions in patients with diabetes and therefore frequently occur concomitantly. Diagnosis of CTS in patients with DPN is important, as therapeutic interventions directed toward relief of CTS may be effective irrespective of diffuse neuropathy. The prevalence of clinical CTS and the most efficient electrodiagnostic discriminators of CTS from diffuse neuropathy are uncertain. RESEARCH DESIGN AND METHODS: A total of 478 subjects, including reference subjects (without diabetes and without neuropathy), nonneuropathic subjects with diabetes, and diabetic subjects with mild, moderate, and severe neuropathy, were evaluated in a cross-sectional design for clinical features of CTS. In the ascertainment of the cohort, a clinical stratification method was used to ensure a broad spectrum of neuropathy severity. All subjects underwent nerve conduction study determinations of median, ulnar, and sural nerve parameters. RESULTS: The prevalence of clinical CTS was 2% in the reference population, 14% in diabetic subjects without DPN, and 30% in those with DPN. Multiple linear regression analysis revealed that mean electrodiagnostic parameters are not significant predictors of clinical CTS in patients with diabetes. Generally, the parameters worsened with severity of neuropathy, but none reliably distinguished diabetic patients with and without CTS. CONCLUSIONS: Given the high prevalence of CTS in patients with DPN and that electrodiagnostic criteria cannot distinguish those with clinical CTS, it is recommended that therapeutic decisions for CTS be made independently of electrodiagnostic findings.  相似文献   
118.
Clin. Otolaryngol. 2011, 36 , 325–335 Background: There has been an increasing incidence of tonsil cancer worldwide. Documenting these changes is crucial to cancer prevention and control measures, resource allocation and understanding disease aetiology. Objective: To analyse the changing epidemiology of tonsil cancer in South East England over a 20‐year period between 1987 and 2006. Design: A retrospective, quantitative study using secondary anonymised data obtained from the Thames Cancer Registry, London. Data were analysed using spss v.17 and survival analyses with Kaplan–Meier and Cox regression. Setting: This study was conducted in South East of England comprising London, Kent, Surrey and Sussex counties with an average population of 12 million. This population increased from 10.7 to 11.8 million (a 10% increase) between 1987 and 2006. Participants: All patients with tonsil cancer in South East England registered with the Thames Cancer Registry (ICD‐10 code C09) between 1987 and 2006. A total of 1794 patients’ data were analysed. Ethical Considerations: Ethical approval was granted by the Kent Research Ethics Committee. Main outcome measures: Data were analysed for demographic trends including gender, age at diagnosis, yearly incidence and survival. Results: Tonsil cancer incidence has increased significantly from 0.60 to 1.45 per 100 000 in the 20 years (P < 0.001). This increase is mainly amongst men and age groups 40–59 years with a significant reduction in age at diagnosis by 2 years from 61.6 years in the first decade to 59.6 years in the second decade (P < 0.001). Survival was worse in men, older age groups and in the presence of synchronous tumours (P < 0.001). There has been a statistically significant increase in median survival times from tonsil cancer by about 3 years from 2.7 years in the first decade to 5.7 years in the second decade of this study (P < 0.001). Conclusions: Tonsil cancer incidence has increased in the 20 years of this study in South East England, especially amongst men and age groups 40–59 years. There has also been significant reduction in the mean age at diagnosis and an increase in median survival times for tonsil cancer. Further studies are needed to explain these trends.  相似文献   
119.

Background

Though the major target of the HIV-virus is the immune system, the frequency of abdominal disorders in HIV/AIDS patients has been reported to be second only to pulmonary disease. These abdominal manifestations may be on the increase as the use of antiretroviral therapy has increased life expectancy and improved quality of life. Ultrasonography is an easy to perform, non invasive, inexpensive and safe imaging technique that is invaluable in Africa where AIDS is most prevalent and where sophisticated diagnostic tools are not readily available. Purpose: To describe the findings and evaluate the clinical utility of abdominal ultrasonography in HIV/AIDS patients in Ibadan, Nigeria

Methods

A Prospective evaluation of the abdominal ultrasonography of 391 HIV-positive patients as well as 391 age and sex-matched HIV-negative patients were carried out at the University College Hospital, Ibadan.

Results

Of the 391 cases studied, 260 (66.5%) were females; the mean age was 38.02 years, (range 15–66 years). The disease was most prevalent in the 4th decade with an incidence of 40.4%. Compared with the HIV-negative individuals, the HIV+ group of patients had a significantly higher proportion of splenomegaly (13.5% vs. 7.7%; p < 0.01), lymphadenopathy (2.0% vs. 1.3%; p < 0.70), and renal abnormalities (8.4% vs. 3.8%; p < 0.02). There were no differences in hepatic and pancreatic abnormalities between the HIV+ and HIV- groups. There were significantly fewer gallstones in the HIV+ group (1.4% vs. 5.1%; p < 0.01).

Conclusion

AIDS is a multi-systemic disease and its demographic and clinical pattern remains the same globally. Ultrasonography is optimally suited for its clinical management especially in Africa. Its accuracy and sensitivity may be much improved with clinico-pathologic correlation which may not be readily available in developing countries; further studies may provide this much needed diagnostic algorithms.  相似文献   
120.
Traditional medicine has provided a basis for health care and disease treatment to Chinese people for millennia, and herbal medicines are regulated as drug products in China. Chinese herbal medicines have two features. They normally possess very complex chemical composition. This makes the identification of the constituents that are together responsible for the therapeutic action of an herbal medicine challenging, because how to select compounds from an herbal medicine for pharmacodynamic study has been a big hurdle in such identification efforts. To this end, a multi-compound pharmacokinetic approach was established to identify potentially important compounds (bioavailable at the action loci with significant exposure levels after dosing an herbal medicine) and to characterize their pharmacokinetics and disposition. Another feature of Chinese herbal medicines is their typical use as or in combination therapies. Coadministration of complex natural products and conventional synthetic drugs is prevalent worldwide, even though it remains very controversial. Natural product–drug interactions have raised wide concerns about reduced drug efficacy or safety. However, growing evidence shows that incorporating Chinese herbal medicines into synthetic drug-based therapies delivers benefits in the treatment of many multifactorial diseases. To address this issue, a drug-combination pharmacokinetic approach was established to assess drug–drug interaction potential of herbal medicines and degree of pharmacokinetic compatibility for multi-herb combination and herbal medicine–synthetic drug combination therapies. In this review we describe the methodology, techniques, requirements, and applications of multi-compound and drug-combination pharmacokinetic research on Chinese herbal medicines and to discuss further development for these two types of pharmacokinetic research.  相似文献   
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