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BackgroundThe objective of this study was to evaluate the anti-inflammatory activities and phytochemical composition of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv.MethodsThe powdered leaves of Boscia coriacea Graells and Uvaria leptocladon Oliv were extracted by maceration and soxhlet extraction methods. Anti-inflammatory activity of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv were evaluated using carrageenan-induced paw edema model. Standard methods were used for analysis of phytochemical composition of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv. Data analysis was done using one way analysis of variance.ResultsU. leptocladon Oliv (200 mg/kg) and B. coriacea Graells (200 mg/kg) showed percent inhibition on mice paw edema of 86% and 75% after six hours of carrageenan injection, respectively. The ethanol fraction (100 mg/kg) of U. leptocladon Oliv showed the highest anti-inflammatory effect after six hours of carrageenan injection. The phytochemical analysis of the leaves extracts of B. coriacea and U. leptocladon revealed the presence of tannins, alkaloids, cardiac glycoside, flavonoids, phenols, quinones, and saponins.ConclusionThe crude leaves extracts of B. coriacea Graells and U. leptocladon Oliv contain phytochemicals with anti-inflammatory activities.  相似文献   
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The presence of a direct estrogen effect on calcitonin secretion is controversial. Because most of the data available were obtained from complex in vivo systems, we chose an in vitro approach to assess the problem. Using a human C cell carcinoma cell line (TT cells) with well-documented estrogen receptors, we investigated the effect of 17 beta-estradiol (E2) on basal and stimulated calcitonin secretion, on calcitonin content, and on total cellular protein. After short (30 and 180 minutes) and long-term (24 h to 6 days) incubation of the cells with different concentrations of E2 (from 0.01 to 100 nM) we observed no stimulatory but a transient dose-dependent inhibitory effect on CT secretion and content. The nadir of the effect on CT secretion appeared at 24 h, demonstrating a reduction to 80.5 +/- 7.8% of control at 1 nM and to 59.1 +/- 15% of control at 100 nM E2. After 72 h, the CT levels of the E2-exposed groups returned to control levels. The acute stimulation of the cells with TPA plus forskolin after preincubation with E2 up to 6 days showed no difference in the increment of CT release compared to the control groups. Additionally, E2 had a dose-dependent stimulatory effect on cell protein content. The data demonstrate the absence of a direct stimulatory effect of E2 on CT secretion, revealing a dose-dependent inhibitory effect on CT secretion and content.  相似文献   
75.
The study was conducted to determine the prevalence, incidence, and risk factors for HIV infection among factory workers at two sites in Ethiopia. During February 1997-December 2001, a structured questionnaire was used for obtaining information on sociodemographics, sexual behaviour, and reported sexually transmitted infections (STIs) from a cohort of 1679 individuals. Serum samples were screened for antibodies against HIV, Treponema pallidum haemaglutination (TPHA), and herpes simplex virus type 2 (HSV-2). The overall baseline prevalence of HIV was 9.4%-8.5% among males and 12.4% among females. For both the sexes, the factors independently associated with an increased risk of HIV infection were widowhood and having had antibodies against TPHA and HSV-2. The risk factors specific for males were being orthodox Christian, having had a higher lifetime number of sexual partners, and genital discharge in the past five years. The risk factors for females, included low income, one or more rape(s) over lifetime, and casual sex in the last year. The overall incidence of HIV infection was 0.4 per 100 person-years. The highest rate of incidence was observed among young women aged less than 30 years (1 per 100 person-years). The study confirmed that high-risk sexual behaviour and STIs play major roles in the spread of HIV infection in the Ethiopians of both the sexes, but the factors, such as rape and low economic status, make women more vulnerable than men.  相似文献   
76.
The cytotoxicity of extracts from a widely used species of plant, Moringa stenopetala, was assessed in HEPG2 cells, by measuring the leakage of lactate dehydrogenase (LDH) and cell viability. The functional integrity of extract-exposed cells was determined by measuring intracellular levels of ATP and glutathione (GSH). The ethanol extracts of leaves and seeds increased significantly (p < 0.01) LDH leakage in a dose- and time-dependent manner. The water extract of leaves and the ethanol extract of the root did not increase LDH leakage. A highly significant (p < 0.001) decrease in HEPG2 viability was found after incubating the cells with the highest concentration (500 microg/mL) of the ethanol leaf and seed extracts. At a concentration of 500 microg/mL, the water extract of leaves increased (p < 0.01), while the ethanol extract of the same plant part decreased (p < 0.01), ATP levels. The root and seed extracts had no significant effect on ATP levels. The ethanol leaf extract decreased GSH levels at a concentration of 500 microg/mL (p < 0.01), as did the ethanol extract of the seeds at 250 microg/mL and 500 microg/mL (p < 0.05). The water extract of the leaves did not alter GSH or LDH levels or affect cell viability, suggesting that it may be non-toxic, and is consistent with its use as a vegetable. The data obtained from the studies with the ethanol extract of the leaves and seeds from Moringa stenopetala show that they contain toxic substances that are extractable with organic solvents or are formed during the process of extraction with these solvents. The significant depletion of ATP and GSH only occurred at concentrations of extract that caused leakage of LDH. Further investigation with this plant in order to identify the constituents extracted and their individual toxic effects both in vivo and in vitro is warranted. This study also illustrates the utility of cell culture for screening plant extracts for potential toxicity.  相似文献   
77.
BACKGROUND AND PURPOSE: The pattern of clinical presentations of tuberculosis (TB) is reflected in the microbiological, radiological, and histological characteristics of the disease. However, coinfection with human immunodeficiency virus (HIV) poses special diagnostic and therapeutic challenges. This study was aimed at assessing the clinical manifestations of TB in patients with or without HIV coinfection in a hospital-based cross-sectional study in Gondar, Ethiopia. METHODS: TB was diagnosed following standard clinical, bacteriological, radiological, and histological procedures. HIV serostatus was checked by enzyme-linked immunosorbent assay. RESULTS: This study included 257 TB patients, of whom 52.1% were coinfected with HIV. Pulmonary TB and extrapulmonary TB were diagnosed in 64.2% and 35.8% of the patients, respectively. No significant association was found between sputum smear positivity and HIV serostatus. One-fifth of the patients reported hemoptysis. More than one-third had chest pain, and >90% reported fever and weight loss. Night sweats and cough were reported by 86% and 82.5%, respectively. Coarse crepitations were the most frequent auscultatory finding (33.9%). Sputum smear positivity rate was 26.8%. Cavitation was significantly associated with sputum smear positivity (odds ratio = 9.0, 95% confidence interval = 2.4-34.1). Wasting, cough of 相似文献   
78.
The health effects of organophosphorus (OP) pesticides on cholinesterase (ChE) activities were assessed among 81 pest control workers from Northern Omo State Farm (Ethiopia), following the occupational use of Chlorpyrifos 25 and 48% ULV and Profenifos 250 EC/ULV. Plasma ChE (PChE) and erythrocyte ChE (AChE) activities were determined electrometrically before and after pesticide exposure. Plasma alkaline phosphatase (AP) and glutamic pyruvic transaminase (GPT) values were estimated colorimetrically. Risk factors of pesticide poisoning and related occupational factors were assessed following the WHO recommendations. The mean PChE and AChE activities determined after pesticide exposures were significantly lower than the pre-exposure values (P < 0.05); 16% and 40% of the pest control workers had PChE and AChE levels below 50% of the pre-exposure values, respectively. The mean plasma AP and GPT values were found to be within the recommended normal limits. No significant difference in either of the ChE activities was observed between the spray men and the pest assessors, although the former were believed to have frequent contact with the concentrated OP formulations. Risk factors of pesticide poisoning such as workers ignorance about the toxicity of pesticides, poor personal hygiene and total absence or improper use of personal protective devices were prevalent. Measures that should be considered to minimize the problem in the farm population are recommended.  相似文献   
79.

Background

Reliable data on causes of death form the basis for building evidence on health policy, planning, monitoring, and evaluation. In Ethiopia, the majority of deaths occur at home and civil registration systems are not yet functional. The main objective of verbal autopsy (VA) is to describe the causes of death at the community or population level where civil registration and death certification systems are weak and where most people die at home without having had contact with the health system.

Methods

Causes of death were classified and prepared based on the International Classification of Diseases (ICD-10). The cause of a death was ascertained based on an interview with next of kin or other caregivers using a standardized questionnaire that draws information on signs, symptoms, medical history, and circumstances preceding death. The cause of death, or the sequence of causes that led to death, is assigned based on the data collected by the questionnaire. The complete VA questionnaires were given to two blinded physicians and reviewed independently. A third physician was assigned to review the case when disagreements in diagnosis arose.

Results

Communicable diseases (519 deaths [48.0%]), non-communicable diseases (377 deaths [34.8%]), and external causes (113 deaths [10.4%]) were the main causes of death between 2007 and 2013. Of communicable diseases, tuberculosis (207 deaths [19.7%]), HIV/AIDS (96 deaths [8.9%]) and meningitis (76 deaths [7.0%]) were the most common causes of death.

Conclusion

Tuberculosis, HIV/AIDS, and meningitis were the most common causes of deaths among adults. Death due to non-communicable diseases showed an increasing trend. Increasing community awareness of infections and their interrelationships, tuberculosis case finding, effective local TB programs, successful treatment, and interventions for HIV are supremely important.
  相似文献   
80.
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