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91.
Visceral Leishmaniasis (VL) is an endemic parasitic disease and remains as a major health concern in southwestern Iran. The current study describes clinico-hematological, epidemiological and therapeutic features of VL cases, admitted to university-affiliated hospitals, during 1999–2014 in Fars province, southwestern Iran. A total of 380 VL cases were recorded during a 16 years period, giving an average annual admission of 23.75 cases/year in which 217 (57.1%) were male and 163 (42.9%) were female. Mean age of the patients was 3.7 years. The majority of the cases (91.5%) were ≤ 5 years old. Bone-marrow aspiration detected Leishmania amastigotes only in 26.6% of cases. Fever (98.1%), abdominal protrusion (65.1%) and hepatosplenomegaly (63.7%) were the most common clinical presentations of the patients. Pancytopenia was noted in 43.1, anemia in 87.3 and thrombocytopenia in 64% of cases. Increase in the level of AST (aspartate aminotransferase), ALT (alanine aminotransferase), alkaline phosphatase, LDH (lactate dehydrogenase) and CRP (C-Reactive Proteins) were seen in 84.9, 53.6, 44.4, 72.5 and 83.1% of cases, respectively. Mortality was noted in 5.3% of cases. Deranged haemato-biochemical parameters including total and direct bilirubin, PLT (platelet) and pancytopenia were significantly contributed to mortality from VL. Moreover, clinical features such as severe splenomegaly as well as bacterial infections were meaningfully contributed to death from VL. The majority of patients (74.9%) were treated with meglumine antimoniate. Amphotericin B was administrated in 59 of cases, 11 of them were initially treated with meglumine antimoniate with a shift to amphotericin B, because of treatment failure. Findings of the current study demonstrated that VL is present in southwest of Iran with a fairly continual rate during the last 16 years period. Deranged haemato-biochemical parameters along with severe splenomegaly contributed to mortality from VL.  相似文献   
92.

Dividing a metal nanoparticle into smaller components and the occurrence of the plasmonic phenomenon in the gap between these components can improve the sensitivity of the detector to variation of the refraction coefficient of liquid. In this paper, in a constant volume of metal, a golden disk is divided into two rings and one smaller disk. With a proper arrangement of these components, the surface plasmon resonance phenomenon takes place at the wavelength of 945.7 nm. The occurrence of this phenomenon increases the field in the distance between nanoparticles surrounded by liquid. The sensitivity of the detector that designed using nanodisks is 300 nm/RIU while it increases to 500 nm/RIU for the new structure. The increase of LSPR displacement, for a variation of 0.01 in the liquid refraction coefficient, from 3 nm for a disk to 5 nm for a proposed structure verifies a 67% improvement in the sensitivity of the sensor.

  相似文献   
93.

Background

A clinical parameter commonly used to assess the neurological status of an individual is the tendon reflex response. However, the clinical method of evaluation often leads to subjective conclusions that may differ between examiners. Moreover, attempts to quantify the reflex response, especially in older age groups, have produced inconsistent results. This study aims to examine the influence of age on the magnitude of the patellar tendon reflex response.

Methodology/Principal Findings

This study was conducted using the motion analysis technique with the reflex responses measured in terms of knee angles. Forty healthy subjects were selected and categorized into three different age groups. Patellar reflexes were elicited from both the left and right patellar tendons of each subject at three different tapping angles and using the Jendrassik maneuver. The findings suggested that age has a significant effect on the magnitude of the reflex response. An angle of 45° may be the ideal tapping angle at which the reflex can be elicited to detect age-related differences in reflex response. The reflex responses were also not influenced by gender and were observed to be fairly symmetrical.

Conclusions/Significance

Neurologically normal individuals will experience an age-dependent decline in patellar reflex response.  相似文献   
94.

Background

There is a recognized gap in the evidence base relating to the nature and components of interventions to address the psycho-social needs of HIV positive young people. We used mixed methods research to strengthen a community support group intervention for HIV positive young people based in Harare, Zimbabwe.

Methods

A quantitative questionnaire was administered to HIV positive Africaid support group attendees. Afterwards, qualitative data were collected from young people aged 15–18 through tape-recorded in-depth interviews (n = 10), 3 focus group discussions (FGDs) and 16 life history narratives. Data were also collected from caregivers, health care workers, and community members through FGDs (n = 6 groups) and in-depth interviews (n = 12). Quantitative data were processed and analysed using STATA 10. Qualitative data were analysed using thematic analysis.

Results

229/310 young people completed the quantitative questionnaire (74% participation). Median age was 14 (range 6–18 years); 59% were female. Self-reported adherence to antiretrovirals was sub-optimal. Psychological well being was poor (median score on Shona Symptom Questionnaire 9/14); 63% were at risk of depression. Qualitative findings suggested that challenges faced by positive children include verbal abuse, stigma, and discrimination. While data showed that support group attendance is helpful, young people stressed that life outside the confines of the group was more challenging. Caregivers felt ill-equipped to support the children in their care. These data, combined with a previously validated conceptual framework for family-centred interventions, were used to guide the development of the existing programme of adolescent support groups into a more comprehensive evidence-based psychosocial support programme encompassing caregiver and household members.

Conclusions

This study allowed us to describe the lived experiences of HIV positive young people and their caregivers in Zimbabwe. The findings contributed to the enhancement of Africaid’s existing programme of support to better promote psychological well being and ART adherence.  相似文献   
95.

Introduction

The inherent low oxygen tension in normal cartilage has implications on inflammatory conditions associated with osteoarthritis (OA). Biomechanical signals will additionally contribute to changes in tissue remodelling and influence the inflammatory response. In this study, we investigated the combined effects of oxygen tension and fibronectin fragment (FN-f) on the inflammatory response of chondrocytes subjected to biomechanical signals.

Methods

Chondrocytes were cultured under free-swelling conditions at 1%, 5% and 21% oxygen tension or subjected to dynamic compression in an ex vivo 3D/bioreactor model with 29 kDa FN-f, interleukin-1beta (IL-1β) and/or the nitric oxide synthase (NOS) inhibitor for 6 and 48 hours. Markers for catabolic activity (NO, PGE2), tissue remodelling (GAG, MMPs) and cytokines (IL-1β, IL-6 and TNFα) were quantified by biochemical assay. Aggrecan, collagen type II, iNOS and COX-2 gene expression were examined by real-time quantitative PCR. Two-way ANOVA and a post hoc Bonferroni-corrected t-test were used to analyse data.

Results

Both FN-fs and IL-1β increased NO, PGE2 and MMP production (all P < 0.001). FN-f was more active than IL-1β with greater levels of NO observed at 5% than 1% or 21% oxygen tension (P < 0.001). Whilst FN-f reduced GAG synthesis at all oxygen tension, the effect of IL-1β was significant at 1% oxygen tension. In unstrained constructs, treatment with FN-f or IL-1β increased iNOS and COX-2 expression and reduced aggrecan and collagen type II (all P < 0.001). In unstrained constructs, FN-f was more effective than IL-1β at 5% oxygen tension and increased production of NO, PGE2, MMP, IL-1β, IL-6 and TNFα. At 5% and 21% oxygen tension, co-stimulation with compression and the NOS inhibitor abolished fragment or cytokine-induced catabolic activities and restored anabolic response.

Conclusions

The present findings revealed that FN-fs are more potent than IL-1β in exerting catabolic effects dependent on oxygen tension via iNOS and COX-2 upregulation. Stimulation with biomechanical signals abolished catabolic activities in an oxygen-independent manner and NOS inhibitors supported loading-induced recovery resulting in reparative activities. Future investigations will utilize the ex vivo model as a tool to identify key targets and therapeutics for OA treatments.  相似文献   
96.
Transhumance sheep and goat production have been a common and traditional practice in Greece, with its origins dating back to ancient times. Despite the diminishing number of transhumance farms, it remains an essential activity in less-favoured and mountainous areas of the country. This article applies DEA (Data Envelopment Analysis) in a sample of transhumance farms in Greece in order to assess the technical efficiency of sheep and goat transhumance flocks and determine the factors that affect their performance. The effect of EU subsidies on the technical efficiency of transhumance farms is assessed and the type of farms that benefit most is investigated. Results accrued reveal that the overall technical efficiency of transhumance farms in Greece is quite low and it is affected by herd size. EU subsidies have a significant impact on the technical efficiency of only the low-efficiency, small-sized farms.  相似文献   
97.
98.
We present results from the OP3 campaign in Sabah during 2008 that allow us to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NO(x) emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.  相似文献   
99.
In recent years, many studies have stated the nutritional benefits of fish consumption: vitamins, proteins and omega-3 fatty acids, which may protect humans from adverse health effects, including heart disease and stroke. This study aimed to evaluate the concentration of Cu, Pb and As in the liver, gills and muscles of tilapia fish (Oreochromis niloticus) and to calculate the weekly intake from eating tilapia collected from Cempaka Lake, Selangor — Peninsular Malaysia during the period between April 2009 to February 2010. The elemental concentrations were determined using inductively — coupled plasma mass spectrometry (ICP-MS). The results showed that all heavy metal concentrations were significantly different among fish organs, and between calendar months. The data showed that Cu levels in liver, gills and muscles were 491.30, 3.70 and 1.82 μg/g dry weight (dw), respectively. Meanwhile Pb levels were 2.71, 1.04 and 0.48 μg/g dw, respectively and As levels were 6.26, 4.18 and 1.79 μg/g dw, respectively. Significant changes occurred in Cu, Pb and As levels in tilapia fish organs in Cempaka Lake over the period of 11 months. Tilapia weekly intake was calculated based on mean Cu, Pb and As concentrations in the muscle of tilapia fish and adult consumption of tilapia in Malaysia which averages at 160 grams per day. Furthermore, tilapia weekly and daily human intakes for Cu, Pb and As were compared with the Provisional Tolerable Weekly Intake (PTWI) established by the JECFA (WHO/FAO) presenting values below the PTWI. Metal levels in fish muscle were found to be lower than the maximum permitted concentrations recommended by various authorities; hence, consumption of tilapia fish from Cempaka Lake is currently safe for humans.  相似文献   
100.
Research on Leishmania-macrophage interaction is mainly focused on the impact of the parasite on macrophages and several known virulent factors have been described. Furthermore, studies on macrophage revealed several defense mechanisms including various cytokines which are released by macrophages to defend against parasite. In the present study, a new aspect of this interaction was evaluated: parasite characteristics, which emerge when they were cocultivated with macrophage. Two promastigote characteristics, survival at high temperature (32 degrees C) and infectivity rate were the focus of this study. In this study, an in vitro coculture model for promastigotes with macrophage cell line, J774 A1, was introduced using a cell culture chamber system which separates both cell types by a microporous polycarbonate membrane. After 5-7 days of coculturing at 32 degrees C, a few promastigotes survived longer than control group. Once this population of parasite was cultured at optimal temperature (26 degrees C), the emerged new clone was much more infective for J774 A1 cell line in comparison with the original one. Having this system and using the new clone of promastigotes, parasite infectivity rate was raised from 1-2% of original clone to 35-45%. Using this new introduced technique, infective promastigotes were isolated from 9 month old frequently sub-cultured clone of Leishmania major. This coculturing system allows investigators to prepare infective promastigotes from the frequently cultured parasites. Molecular and biochemical mechanisms of this phenomenon need to be investigated.  相似文献   
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