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101.
During 2003 and during late September of 2004, more than 1230 cases of gastroenteritis were reported in the south of Sinaloa State, north-western Mexico. All cases were attributed to the consumption of raw or undercooked shrimp collected at the Huizache-Caimanero lagunary system. Vibrio parahaemolyticus was identified by standard biochemical methods, and many strains were positive for PCR amplifications of the tlh and tdh genes and negative for the trh gene. A representative strain belonged to the O3:K6 serogroup. This is the first outbreak of gastroenteritis caused by the pandemic strains of O3:K6 V. parahaemolyticus in México.  相似文献   
102.
Giardia and Cryptosporidium are important causes of diarrhoea in Bangladesh. The high prevalence of both parasites in humans and cattle in rural Bangladesh and the common use of water ponds by village inhabitants and their animals suggest a potential for zoonotic transmission. Direct transmission of Giardia and Cryptosporidium between cattle and their handlers and indirect transmission through water ponds was investigated. Faecal/stool samples were collected from 623 calves and 125 calf handlers in a cross-sectional survey. In two villages, water samples were collected monthly from water ponds and faecal/stool samples were collected monthly from inhabitants and their cattle. Giardia cysts and Cryptosporidium oocysts were detected in water samples and in faecal/stool samples and positive samples were genotyped, to determine their human or animal origin. The prevalence of Giardia and Cryptosporidium in calves was 22% and 5% respectively. In calf handlers, the prevalence of Giardia and Cryptosporidium was 11.2% and 3.2% respectively. Both in the cross-sectional survey and in the longitudinal study in the villages, G. duodenalis assemblage E was most prevalent in calves, while in humans assemblage AII, BIII and BIV were found. In cattle, Cryptosporidium parvum, C. bovis and C. andersoni were identified, but no Cryptosporidium sequences were obtained from humans. Giardia and Cryptosporidium were detected in 14/24 and 12/24 water samples respectively. G. duodenalis assemblage E and BIV (-like), as well as C. andersoni and C. hominis were identified. Although the presence of Giardia and Cryptosporidium in both water ponds suggests that water-borne transmission of Giardia and Cryptosporidium is possible, the genotyping results indicate that there is no significant direct or indirect (water-borne) transmission of Giardia between cattle and people in this area of rural Bangladesh. No conclusions could be drawn for Cryptosporidium, because of the low number of sequences that were obtained from human and water samples.  相似文献   
103.
The lack of a reliable and innocuous mark-recapture method has limited studies that would provide essential information for the management of commercial sea cucumbers. Tagging sea cucumbers is notoriously difficult because of their plastic nature and autolysis capacities. The markers that have so far been tested, mainly on or through the body wall, were either lost rapidly or had major drawbacks (e.g. suitable only for batch identification, requiring complex analysis, causing infections, necrosis, behavioural changes and mortality). The present study explored the efficacy of passive integrated transponder (PIT) tags for individually marking sea cucumbers by assessing retention rates and long-term side effects of tags inserted in previously unstudied tissues/organs. Individuals of the species Cucumaria frondosa were tagged in the body wall, aquapharyngeal bulb and at the base of the oral tentacles. They were monitored closely for evidence of stress, infection, change in feeding and spawning behaviour and tag retention rate. Implanting the tag in an oral tentacle to reach the hydrovascular system of the aquapharyngeal bulb achieved the best retention rates in full-size individuals: from a maximum of 92% after 30 days to 68% at the end of the experimental period (300 days). Efficacy was lower in smaller individuals (84% after 30 d and 42% after 300 d). Following a slight increase in cloacal movements for 15 h post tagging, no side effect was noted in sea cucumbers tagged in the aquapharyngeal bulb via the tentacles. Feeding and spawning behaviours were not affected and no signs of infections or abnormal cell development in the vicinity of the tags were observed. This study indicates that marking sea cucumbers with 8.2 mm long PIT tags implanted via the oral tentacle is an effective technique, yielding relatively high retention rates over long periods without any detectable physiological or behavioural effects.  相似文献   
104.
Uterine leiom yomas are benign tumors highly prevalent in reproductive women. In thecurrent study, initially, we aimed to screen five different strawberry cultivars (Alba, Clery, Portola, Tecla, and Romina) to identify efficient cultivars in terms of phytochemical characterization and biological properties by measuring phenolic and anthocyanin content as well as antioxidant capacity, and by measuring apoptotic rate and reactive oxygen species (ROS) production in uterine leiomyoma cells. Next, we focused on the most efficient ones, cultivar Alba (A) and Romina (R) as well as Romina anthocyanin (RA) fraction for their ability to regulate oxidative phosphorylation (oxygen consumption rate [OCR]) glycolysis (extracellular acidification rate [ECAR]), and also fibrosis. Leiomyoma and myometrial cells were treated with a methanolic extract of A and R (250 μg/ml) or with RA (50 μg/ml) for 48 hr to measure OCR and ECAR, as well as gene expression associated with fibrosis. In the leiomyoma cells, RA was more effective in inducing apoptosis and increasing intracellular ROS levels, followed by R and A. In myometrial cells, all strawberry treatments increased the cellular viability and decreased ROS concentrations. Leiomyoma cells showed also a significant decrease in ECAR, especially after RA treatment, while OCR was slightly increased in both myometrial and leiomyoma cells. R and RA treatment significantly decreased collagen 1A1, fibronectin, versican, and activin A messenger RNA expression in leiomyoma cells. In conclusion, this study suggests that Romina, or its anthocyanin fraction, can be developed as a therapeutic and/or preventive agent for uterine leiomyomas, confirming the healthy effects exerted by these fruits and their bioactive compounds.  相似文献   
105.
106.

Objective

Given that helminth infections have been shown to improve insulin sensitivity in animal studies, which may be explained by beneficial effects on energy balance or by a shift in the immune system to an anti-inflammatory profile, we investigated whether soil-transmitted helminth (STH)-infected subjects are more insulin sensitive than STH-uninfected subjects.

Design

We performed a cross-sectional study on Flores island, Indonesia, an area with high prevalence of STH infections.

Methods

From 646 adults, stool samples were screened for Trichuris trichiura by microscopy and for Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale, and Strongyloides stercoralis by qPCR. No other helminth was found. We collected data on body mass index (BMI, kg/m2), waist-to-hip ratio (WHR), fasting blood glucose (FBG, mmol/L), insulin (pmol/L), high sensitive C-reactive protein (ng/ml) and Immunoglobulin E (IU/ml). The homeostatic model assessment for insulin resistance (HOMAIR) was calculated and regression models were used to assess the association between STH infection status and insulin resistance.

Results

424 (66%) participants had at least one STH infection. STH infected participants had lower BMI (23.2 vs 22.5 kg/m2, p value = 0.03) and lower HOMAIR (0.97 vs 0.81, p value = 0.05). In an age-, sex- and BMI-adjusted model a significant association was seen between the number of infections and HOMAIR: for every additional infection with STH species, the HOMAIR decreased by 0.10 (p for linear trend 0.01). This effect was mainly accounted for by a decrease in insulin of 4.9 pmol/L for every infection (p for trend = 0.07).

Conclusion

STH infections are associated with a modest improvement of insulin sensitivity, which is not accounted for by STH effects on BMI alone.  相似文献   
107.
Benthic algal mats and phytoplankton of Lake Gondwana (Northern Victoria Land, Antarctica) were investigated. Biomass, chlorophyll content and floristic analyses were carried out on algal mats. The mats are composed of two layers different in colour, floristic composition and chlorophyll content. The algal flora of the mats amount to 34 taxa (19 Cyanophyta, 7 Bacillariophyta, 8 Chlorophyta). The phytoplankton community is species-poor (only 5 taxa). Crytophyta account for about 98% of total algal density.  相似文献   
108.
Mussels were translocated from a shell-fish breeding area (Sète, on the French Mediterranean coast) to sites exposed to trace element inputs in April 2000. They were recovered 3 months later. Whole soft tissues from all of the sites (n = 97) were analysed for arsenic, cadmium, chromium, copper, mercury, nickel, lead and zinc. Metallothioneins (MTs) were also measured in the digestive gland and in the remaining tissues (allowing calculation of whole soft tissue concentrations) at 22 of the 97 sites. MT concentrations in the digestive gland and the whole soft tissues were strongly correlated. The condition index varied with food availability at different sites. This did not influenced MT concentrations in the whole soft tissues, whereas the condition index was negatively correlated to trace element concentrations. A model is proposed to minimize this influence of condition. Metal concentrations adjusted using this model showed significant correlations with MT levels for those metals (cadmium, copper, nickel and zinc) that are known to bind to this protein, with the exception of mercury. Even in moderately contaminated sites, measurement of the MT level in the soft tissues of mussels was generally able to discriminate between different levels of contamination, allowing the use of a simplified procedure compared with dissection of the digestive gland. It is recommended to avoid translocation and sampling during the reproductive period, which is well documented for commercial species such as Mytilus sp.  相似文献   
109.
110.
BackgroundDiabetes mellitus (DM) has been associated with increased risk for pulmonary tuberculosis (PTB) in endemic settings but it is unknown whether PTB risk is also increased by pre-DM. Here, we prospectively examined the association between glucose metabolism disorder (GMD) and PTB in patients with respiratory symptoms at a tuberculosis primary care reference center in Brazil.MethodsOral glucose tolerance test was performed and levels of fasting plasma glucose and glycohemoglobin (HbA1c) were measured in a cohort of 892 individuals presenting with respiratory symptoms of more than two weeks duration. Patients were also tested for PTB with sputum cultures. Prevalence of pre-DM and DM (based on HbA1c) was estimated and tested for association with incident PTB. Other TB risk factors including smoking history were analyzed.ResultsThe majority of the study population (63.1%) exhibited GMD based on HbA1c ≥5.7%. Patients with GMD had higher prevalence of PTB compared to normoglycemic patients. Individuals with DM exhibited increased frequency of TB-related symptoms and detection of acid-fast bacilli in sputum smears. Among patients with previous DM diagnosis, sustained hyperglycemia (HbA1c ≥7.0%) was associated with increased TB prevalence. Smoking history alone was not significantly associated with TB in our study population but the combination of smoking and HbA1c ≥7.0% was associated with 6 times higher odds for PTB.ConclusionsSustained hyperglycemia and pre-DM are independently associated with active PTB. This evidence raises the question whether improving glycemic control in diabetic TB patients would reduce the risk of TB transmission and simultaneously reduce the clinical burden of disease. A better understanding of mechanisms underlying these associations, especially those suggesting that pre-DM may be a factor driving susceptibility to TB is warranted.  相似文献   
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