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1.
The Trypanosoma spp. cause animal and human trypanosomiasis characterized with appreciable health and economic burden mostly in developing nations. There is currently no effective therapy for this parasitic disease, due to poor drug efficacy, drug resistance, and unwanted toxicity, etc. Therefore, new anti-Trypanosoma agents are urgently needed. This study explored new series of imidazoles for anti-Trypanosoma properties in vitro and in vivo. The imidazoles showed moderate to strong and specific action against growth of T. congolense. For example, the efficacy of the imidazole compounds to restrict Trypanosoma growth in vitro was ≥ 12-fold specific towards T. congolense relative to the mammalian cells. Additionally, the in vivo study revealed that the imidazoles exhibited promising anti-Trypanosoma efficacy corroborating the in vitro anti-parasite capacity. In particular, three imidazole compounds (C1, C6, and C8) not only cleared the systemic parasite burden but cured infected rats after no death was recorded. On the other hand, the remaining five imidazole compounds (C2, C3, C4, C5, and C7) drastically reduced the systemic parasite load while extending survival time of the infected rats by 14 days as compared with control. Untreated control died 3 days post-infection, while the rats treated with diminazene aceturate were cured comparable to the results obtained for C1, C6, and C8. In conclusion, this is the first study demonstrating the potential of these new series of imidazoles to clear the systemic parasite burden in infected rats. Furthermore, a high selectivity index of imidazoles towards T. congolense in vitro and the oral LD50 in rats support anti-parasite specific action. Together, findings support the anti-parasitic prospects of the new series of imidazole derivatives.  相似文献   
2.
Amino Acids - The antidiabetic effect of l-leucine has been attributed to its modulatory effect on glucose uptake and lipid metabolism in muscles. However, there is a dearth on its effect on...  相似文献   
3.
Immunological and biochemical evidence has been obtained for an interaction of maize protein phosphatase 2A (PP2A) holoenzyme with tubulin. Tubulin co-purifies with maize seedling PP2A. Affinity chromatography of the maize PP2A preparation on immobilized tubulin revealed two peaks of phosphorylase alpha phosphatase activity. In one of the peaks, the catalytic (C) and constant regulatory (A) subunits of PP2A were identified by Western blotting. The subunits (C and A) of PP2A were co-immunoprecipitated from maize seedlings homogenate by an anti-alpha-tubulin antibody. The interaction of plant PP2A with tubulin indicates a possible role of reversible protein phosphorylation in the dynamic structure of plant cytoskeleton.  相似文献   
4.
In this study, an efficient procedure was established for successful induction of tetraploid Arachis paraguariensis by treating diploid explants with colchicine. Quartered-seed, callus and shoot-tips were treated with colchicine at concentrations of 0.05, 0.1, 0.2 and 0.5?% (w/v) for 4, 8, 16, 20 and 24?h before they were transferred unto modified Murashige and Skoog medium for either callus induction or shoot regeneration. Results showed that quartered-seed displayed the highest frequency of in vitro plantlet regeneration and tetraploid induction, as well as the lowest mortality rate. Flow cytometric analysis also confirmed that the induced tetraploids from quartered-seed were true-to-type. The 0.5?% colchicine treatment for 4 to 8?h gave the best results with 39 and 43?% of the explants yielding tetraploid plants, respectively. Two?months following transfer to ex vitro environment, morphological and growth characteristics of the induced tetraploids were measured. Overall, increasing the ploidy level from 2× to 4× resulted in fewer stomata but more trichomes per unit leaf area. Tetraploid plants obtained in this study should expand the genetic base of Arachis, and can also be used in overcoming the existing hybridization barriers that may be due to ploidy differences within the genus Arachis.  相似文献   
5.

Introduction

Hyperglycemia promotes myocardial fibrotic lesions through upregulation of PKC and p38 in response to redox changes. The effects of naringin on hyperglycemia-induced myocardial fibrotic changes and its putative effects on PKC-β and p38 protein expression in type 1 rat model of diabetes are hereby investigated.

Methods

Male Sprague-Dawley rats were divided into six groups I-VI. Groups I and II, were orally treated with distilled water {3.0 ml/kg body weight (BW)} and naringin (50 mg/kg BW), respectively. Groups III, IV, V and VI were rendered diabetic by a single intraperitoneal injection of streptozotocin (60 mg/kg, BW) and were similarly treated with subcutaneous insulin (8.0 I.U/kg BW, twice daily), naringin (50 mg/kg BW), distilled water (3.0 ml/Kg BW) and ramipril (3.0 mg/kg/BW), respectively. The animals were sacrificed after 56 days by halothane overdose; blood and heart samples removed for further analysis.

Results

The untreated diabetic rats exhibited significantly increased oxidative stress, NADPH oxidase activity, increased cardiac fibrosis, PKC-β and p38 mitogen activated protein kinase expression compared to controls. Naringin treatment significantly ameliorated these changes in diabetic rats compared to the untreated diabetic controls.

Conclusions

Naringin’s amelioration of myocardial fibrosis by modulating p38 and PKC-β protein expression possibly through its known antioxidant actions and may therefore be useful in retarding the progression of fibrosis in a diabetic heart.  相似文献   
6.

Background

The diagnosis of tuberculosis (TB) in resource-limited settings relies on Ziehl-Neelsen (ZN) smear microscopy. LED fluorescence microscopy (LED-FM) has many potential advantages over ZN smear microscopy, but requires evaluation in the field. The aim of this study was to assess the sensitivity/specificity of LED-FM for the diagnosis of pulmonary TB and whether its performance varies with the timing of specimen collection.

Methods and Findings

Adults with cough ≥2 wk were enrolled consecutively in Ethiopia, Nepal, Nigeria, and Yemen. Sputum specimens were examined by ZN smear microscopy and LED-FM and compared with culture as the reference standard. Specimens were collected using a spot-morning-spot (SMS) or spot-spot-morning (SSM) scheme to explore whether the collection of the first two smears at the health care facility (i.e., “on the spot”) the first day of consultation followed by a morning sample the next day (SSM) would identify similar numbers of smear-positive patients as smears collected via the SMS scheme (i.e., one on-the-spot-smear the first day, followed by a morning specimen collected at home and a second on-the-spot sample the second day). In total, 529 (21.6%) culture-positive and 1,826 (74.6%) culture-negative patients were enrolled, of which 1,156 (49%) submitted SSM specimens and 1,199 (51%) submitted SMS specimens. Single LED-FM smears had higher sensitivity but lower specificity than single ZN smears. Using two LED-FM or two ZN smears per patient was 72.8% (385/529, 95% CI 68.8%–76.5%) and 65.8% (348/529, 95% CI 61.6%–69.8%) sensitive (p<0.001) and 90.9% (1,660/1,826, 95% CI 89.5%–92.2%) and 98% (1,790/1,826, 95% CI 97.3%–98.6%) specific (p<0.001). Using three LED-FM or three ZN smears per patient was 77% (408/529, 95% CI 73.3%–80.6%) and 70.5% (373/529, 95% CI 66.4%–74.4%, p<0.001) sensitive and 88.1% (95% CI 86.5%–89.6%) and 96.5% (95% CI 96.8%–98.2%, p<0.001) specific. The sensitivity/specificity of ZN smear microscopy and LED-FM did not vary between SMS and SSM.

Conclusions

LED-FM had higher sensitivity but, in this study, lower specificity than ZN smear microscopy for diagnosis of pulmonary TB. Performance was independent of the scheme used for collecting specimens. The introduction of LED-FM needs to be accompanied by appropriate training, quality management, and monitoring of performance in the field.

Trial Registration

Current Controlled Trials ISRCTN53339491 Please see later in the article for the Editors'' Summary  相似文献   
7.
Graded extracts of neem seed oil extracted across the savanna agro-ecological zones (AEZs) of Nigeria were tested on mycelial growth of Colletotrichum capsici and Macrophomina phaseolina of cowpea in Nigeria. Minimum inhibition concentrations (MIC) and effectiveness levels of oil from AEZs were determined. Data were subject to ANOVA. Biplot was employed to access variation and interactions among the AEZs. Across the AEZs, fungitoxicity, MIC and effectiveness level varies; concentrations of 0.1 and 1.0% reduced the growth of C. capsici, while M. phaseolina was reduced at 10% concentration. On M. phaseolina, neem oil extracted from Ilorin, Ogbomosho (derived savanna) and Mokwa (southern guinea savanna) performed similarly, while a strong positive association existed between Ogbomosho (derived savanna) and Hadejia (Sahel savanna) samples. On C. capsici, samples from Bida (southern guinea savanna) and Ilorin (Derived savanna) were similar. This result could be a possible link between ecology, biodiversity and toxic principles in plant materials.  相似文献   
8.

Background

The surge of donor funds to fight HIV&AIDS epidemic inadvertently resulted in the setup of laboratories as parallel structures to rapidly respond to the identified need. However these parallel structures are a threat to the existing fragile laboratory systems. Laboratory service integration is critical to remedy this situation. This paper describes an approach to quantitatively measure and track integration of HIV-related laboratory services into the mainstream laboratory services and highlight some key intervention steps taken, to enhance service integration.

Method

A quantitative before-and-after study conducted in 122 Family Health International (FHI360) supported health facilities across Nigeria. A minimum service package was identified including management structure; trainings; equipment utilization and maintenance; information, commodity and quality management for laboratory integration. A check list was used to assess facilities at baseline and 3 months follow-up. Level of integration was assessed on an ordinal scale (0 = no integration, 1 = partial integration, 2 = full integration) for each service package. A composite score grading expressed as a percentage of total obtainable score of 14 was defined and used to classify facilities (≤80% FULL, 25% to 79% PARTIAL and <25% NO integration). Weaknesses were noted and addressed.

Results

We analyzed 9 (7.4%) primary, 104 (85.2%) secondary and 9 (7.4%) tertiary level facilities. There were statistically significant differences in integration levels between baseline and 3 months follow-up period (p<0.01). Baseline median total integration score was 4 (IQR 3 to 5) compared to 7 (IQR 4 to 9) at 3 months follow-up (p = 0.000). Partial and fully integrated laboratory systems were 64 (52.5%) and 0 (0.0%) at baseline, compared to 100 (82.0%) and 3 (2.4%) respectively at 3 months follow-up (p = 0.000).

Discussion

This project showcases our novel approach to measure the status of each laboratory on the integration continuum.  相似文献   
9.

Background

More than 50 million people around the world are investigated for tuberculosis using sputum smear microscopy annually. This process requires repeated visits and patients often drop out.

Methods and Findings

This clinical trial of adults with cough ≥2 wk duration (in Ethiopia, Nepal, Nigeria, and Yemen) compared the sensitivity/specificity of two sputum samples collected “on the spot” during the first visit plus one sputum sample collected the following morning (spot-spot-morning [SSM]) versus the standard spot-morning-spot (SMS) scheme. Analyses were per protocol analysis (PPA) and intention to treat (ITT). A sub-analysis compared just the first two smears of each scheme, spot-spot and spot-morning.In total, 6,627 patients (3,052 SSM/3,575 SMS) were enrolled; 6,466 had culture and 1,526 were culture-positive. The sensitivity of SSM (ITT, 70.2%, 95% CI 66.5%–73.9%) was non-inferior to the sensitivity of SMS (PPA, 65.9%, 95% CI 62.3%–69.5%). Similarly, the specificity of SSM (ITT, 96.9%, 95% CI 93.2%–99.9%) was non-inferior to the specificity of SMS (ITT, 97.6%, 95% CI 94.0%–99.9%). The sensitivity of spot-spot (ITT, 63.6%, 95% CI 59.7%–67.5%) was also non-inferior to spot-morning (ITT, 64.8%, 95% CI 61.3%–68.3%), as the difference was within the selected −5% non-inferiority limit (difference ITT = 1.4%, 95% CI −3.7% to 6.6%). Patients screened using the SSM scheme were more likely to provide the first two specimens than patients screened with the SMS scheme (98% versus 94.2%, p<0.01). The PPA and ITT analysis resulted in similar results.

Conclusions

The sensitivity and specificity of SSM are non-inferior to those of SMS, with a higher proportion of patients submitting specimens. The scheme identifies most smear-positive patients on the first day of consultation.

Trial Registration

Current Controlled Trials ISRCTN53339491 Please see later in the article for the Editors'' Summary  相似文献   
10.

Background

Recent studies have described the burden of disease in South Africa. However these studies do not tell us which of these conditions commonly present to primary care providers, how these conditions may present and how providers make sense of them in terms of their diagnoses. Clinical nurse practitioners are the main primary care providers and need to be better prepared for this role. This study aimed to determine the range and prevalence of reasons for encounter and diagnoses found among ambulatory patients attending public sector primary care facilities in South Africa.

Methodology/Principal Findings

The study was a multi-centre prospective cross-sectional survey of consultations in primary care in four provinces of South Africa: Western Cape, Limpopo, Northern Cape and North West. Consultations were coded prior to analysis by using the International Classification of Primary Care-Version 2 in terms of reasons for encounter (REF) and diagnoses. Altogether 18856 consultations were included in the survey and generated 31451 reasons for encounter (RFE) and 24561 diagnoses. Women accounted for 12526 (66.6%) and men 6288 (33.4%). Nurses saw 16238 (86.1%) and doctors 2612 (13.9%) of patients. The top 80 RFE and top 25 diagnoses are reported and ongoing care for hypertension was the commonest RFE and diagnosis. The 20 commonest RFE and diagnoses by age group are also reported.

Conclusions/Significance

Ambulatory primary care is dominated by non-communicable chronic diseases. HIV/AIDS and TB are common, but not to the extent predicted by the burden of disease. Pneumonia and gastroenteritis are commonly seen especially in children. Women''s health issues such as family planning and pregnancy related visits are also common. Injuries are not as common as expected from the burden of disease. Primary care providers did not recognise mental health problems. The results should guide the future training and assessment of primary care providers.  相似文献   
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