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991.
Microtox solid phase test is an acute toxicity test for solid matrices based on inhibition of natural bioluminescence of the marine bacterium Vibrio fischeri. Protocols developed to overcome the effects of confounding factors are proposed in the literature that differs by important practical and methodological issues. This work focused on diluents used for sediment resuspension and dilution. Two artificial seawaters, one natural seawater and two phosphate buffer solutions, were compared. The results showed that toxicity data obtained using different diluents were not comparable and that test sensitivity is highest using 0.1M phosphate buffer solution. The effects of medium on test organism were also investigated, in order to verify the capacity of media to maintain bioluminescence. The results underlined the importance of pH and Eh to explain the observed differences in toxicity.  相似文献   
992.
Inflammation persists in patients infected with HIV. Reduction of inflammatory cytokines and microbial translocation might be one way that this could be managed. Purpose: The anti-inflammatory properties of certain probiotic strains prompted us to investigate whether a probiotic could reduce the inflammatory index of HIV-infected patients. Methods: The study involved 30 HIV+ males on antiretroviral therapy, who were given one bottle of fermented milk Yakult Light® containing Lactobacillus casei Shirota (LcS) twice a day for four weeks. Results: The probiotic LcS was associated with an increase of T lymphocytes and a significant increase of CD56+ cells (p = 0.04). There was also a significant decrease of mRNA levels of TGFβ, IL-10 and IL-12 (p < 0.001) and IL-1β expression (p < 0.001) and an increase of serum IL-23 (p = 0.03). In addition, decreased inflammation and cardiovascular risk were observed, as shown by a reduction of cystatin C (p < 0.001). Conclusions: These data provide preliminary evidence that probiotic supplementation may modulate certain immunological parameters and some of the cytokines that were analyzed. Thus, we propose that LcS may be an inexpensive and practical strategy to support the immune function of HIV+ patients.  相似文献   
993.

Ethnopharmacological relevance

This paper illustrates the results of an ethnobotanical study carried out in the Madonie Regional Park (Central Sicily, Italy). It specifies the medicinal uses of plants in the study area and contains the results of a quantitative analysis carried out for the first time in an area noted for its high degree of biodiversity. It also introduces 28 species not previously accounted for in the area of study for their medicinal uses, highlighting Silene flos-cuculi L. Greuter & Burdet, little known as medicinal in the Mediterranean area.

Aim of the study

To understand to what extent current knowledge on medicinal-use plants is still an element of the culture within the elderly population of the Madonie Regional Park.

Methodology

The information was obtained using a semi-structured interview format performed on 150 informants over the age of 60 who were considered experts in plants and rural traditions. The taxa were identified and the results were analysed also using a range of quantitative ethnobotanical indices.

Results

A census was made of 174 wild plant species, 100 of which with medicinal and veterinary uses, belonging to 49 botanical families. Of the 170 endemic species found in the Madonie Regional Park, only 2 species were cited in this study for medicinal purposes. Most of the species were used against dermatological diseases, general health and metabolic disorders. The leaves were the most-used parts of the plant and the most common preparation methods were decoction and infusion. The level of knowledge on medicinal uses of the plants was not found to be high within the elderly population, demonstrating an ongoing process of cultural erosion.

Conclusions

Only very few medicinal uses are widely known by all the informants and, on many occasions, a specific medicinal use was cited by only very few people. Further study is required in order to find out to what extent knowledge on the medicinal use of plants is still present in the younger generations in this area of Sicily, and what methods might be adopted in order to halt this gradual loss in knowledge.  相似文献   
994.
Introduction: The levels of docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are critical for the normal structure and function of the brain. Trans fatty acids (TFA) and the source of the dietary fatty acids (FA) interfere with long-chain polyunsaturated fatty acids (LC-PUFA) biosynthesis.

Objectives: The aim of this study was to investigate the effect of TFA supplementation in diets containing different proportions of n-9, n-6, and n-3 FA on the brain FA profile, including the retention of TFA, LC-PUFA levels, and n-6/n-3 PUFA ratios. These parameters were also investigated in the liver, considering that LC-PUFA are mainly bioconverted from their dietary precursors in this tissue and transported by serum to the brain. Also, stearoyl-CoA desaturase-1 (SCD1) and sterol regulatory element-binding protein-1c (SREBP-1c) gene expressions were evaluated.

Methods: Male CF1 mice were fed (16 weeks) diets containing different oils (olive, corn, and rapeseed) with distinct proportions of n-9, n-6, and n-3 FA (55.2/17.2/0.7, 32.0/51.3/0.9, and 61.1/18.4/8.6), respectively, substituted or not with 0.75% of TFA. FA composition of the brain, liver, and serum was assessed by gas chromatography.

Results: TFA were incorporated into, and therefore retained in the brain, liver, and serum. However, the magnitude of retention was dependent on the tissue and type of isomer. In the brain, total TFA retention was lower than 1% in all diets.

Discussion: Dietary n-3 PUFA decreased TFA retention and increased DHA accretion in the brain. The results underscore the importance of the type of dietary FA on the retention of TFA in the brain and also on the changes of the FA profile.  相似文献   

995.

Purpose

At relatively low concentrations, flavanols induce inconsistent effects on isolated arterial tone, sometimes explained as being due to a structure–activity relationship. The aim of our study was to investigate the effects of two flavanols at different doses on arterial functional state.

Methods

The effects of two catechins, (?)-epigallocatechin-3-gallate (EGCG) and (?)-epicatechin (EP), on rat-isolated aorta tone were investigated on resting tension and on precontracted preparations, both in the presence and in the absence of endothelium.

Results

At resting tension, endothelium-intact preparations, EGCG and EP (0.01–10 μM), induced a slight concentration-dependent, non-significant contraction. On endothelium-denuded preparations, both EGCG and EP induced a concentration-dependent contraction (significance at 0.1 and 1 μM concentrations of the two compounds, respectively). In phenylephrine (PE) (1 μM) precontracted, endothelium-intact preparations, EGCG and EP (0.01–10 μM), induced a concentration-dependent vasorelaxation, reaching significance at 1 μM concentration of both agonists. On endothelium-denuded preparations, EGCG and EP did not significantly affect PE (0.3 μM)-induced tone. In endothelium-intact precontracted preparations, Nω nitro-l-arginine (L-NNA), a nitric oxide synthase (NOS) activity inhibitor, abolished the vasorelaxant effect of EGCG and EP (0.01–10 μM). At high concentrations, EGCG and EP (100 μM) elicited a marked relaxation. This was significantly larger in the presence than in the absence of endothelium or in the presence of L-NNA.

Conclusions

Our findings highlight the important role played by an endothelium/NO-mechanism in the regulation of basal tone and in both mediating vasorelaxation and counteracting vasoconstriction induced by low concentrations of flavanols in rat thoracic aorta.  相似文献   
996.
During the postpartum period, ethnic minority women have higher rates of inactivity/under-activity than white women. The Nā Mikimiki (“the active ones”) Project is designed to increase moderate-to-vigorous physical activity over 18 months among multiethnic women with infants 2–12 months old. The study was designed to test, via a randomized controlled trial, the effectiveness of a tailored telephone counseling of moderate-to-vigorous physical activity intervention compared to a print/website materials-only condition. Healthy, underactive women (mean age = 32 ± 5.6 years) with a baby (mean age = 5.7 ± 2.8 months) were enrolled from 2008–2009 (N = 278). Of the total sample, 84% were ethnic minority women, predominantly Asian–American and Native Hawaiian. Mean self-reported baseline level of moderate-to-vigorous physical activity was 40 minutes/week with no significant differences by study condition, ethnicity, infant's age, maternal body mass index, or maternal employment. Women had high scores on perceived benefits, self-efficacy, and environmental support for exercise but low scores on social support for exercise. This multiethnic sample's demographic and psychosocial characteristics and their perceived barriers to exercise were comparable to previous physical activity studies conducted largely with white postpartum women. The Nā Mikimiki Project's innovative tailored technology-based intervention and unique population are significant contributions to the literature on moderate-to-vigorous physical activity in postpartum women.  相似文献   
997.
To determine if increased lead absorption was associated with sperm count suppression or perterbation of the hypothalamopituitary system, we compared battery workers (N=18), who were exposed to high airborne lead levels, with cement workers (N=18), who were exposed to ambient lead levels. Blood lead, urinary lead, semen lead, and zinc protoporphyrin concentrations were markedly elevated (p<.001) in battery workers. Battery workers had a significantly shifted (p<.025) frequency distribution of sperm count (median count, 45 vs. 73 × 106 cells/cc, respectively). There were no significant differences between the two groups in mean follicle-stimulating hormone, testosterone, prolactin, luteinizing hormone, or total neutral 17-ketosteroid levels. Potential confounding factors (alcohol, cigarette, and coffee consumption, frequency of intercourse, and days of abstinence prior to semen donation) were not significantly different between the two groups. These results suggest a direct toxic effect of increased lead absorption on sperm production or transport in man.  相似文献   
998.
BackgroundImmigration to the United States has been associated with obesity, yet the relationship of acculturation to obesity and energy balance (ie, physical activity/dietary intake) in adults is a complex issue. Limited longitudinal data are available on immigrant Asians and Pacific Islanders.DesignAnalyses were conducted on baseline data and change data from baseline to 24 months in the hotel-based cluster-randomized Work, Weight and Wellness trial involving 15 control and 15 intervention hotels on the island of Oahu, Hawaii.SampleParticipants were adult employees of predominantly Asian and Pacific Islander ancestry who were assessed one or more times over the course of 24 months. The full sample consisted of 4,236 hotel workers (about 40% of hotel workforce) at baseline, 3,502 hotel workers at Year 1 and 2,963 hotel workers at the 24-month follow up. One thousand one hundred fifteen hotel workers had at least two measurements, and were included in the analysis.InterventionThe Work, Weight, and Wellness trial was designed to promote weight loss via motivation and support for increases in physical activity and increased access to and consumption of healthy low-fat/low-energy foods. The measure of acculturation consisted of a score that was a compilation of a participant's age when he or she immigrated to the United States, country of birth, language spoken at home, and years of education.Statistical analysesWe used mixed effect regression models for cross-sectional baseline models and longitudinal multilevel regression analysis of change in diet and physical activity behaviors and obesity over time using a random intercept. Estimates of the intervention effect are expressed as an annual rate of change for all study outcomes.ResultsAt baseline acculturation was positively associated with body mass index; physical activity level; and fruit, meat, and sweetened drink intake level. In analyses of change across 24 months, acculturation did not significantly influence change in dietary intake or indexes of obesity (ie, body mass index or waist-to-height ratio). However physical activity increased significantly more in the intervention group during the course of the intervention compared with the control group, which decreased activity, when sociodemographic factors (including acculturation) and food intake behavior were controlled for.  相似文献   
999.
A series of 1,8-naphthyridine derivatives variously substituted in the 2, 3, 4 and 7 positions were synthesized for in vitro evaluation of antimycobacterial activity in accordance with an international program with the tuberculosis antimicrobial acquisition and coordinating facility (TAACF). Several compounds 4, 8, 12, 14, 19, 29 and 30, when tested at a concentration of 6.25 microg/ml against Mycobacterium tuberculosis H37Rv, showed an interesting activity with % inhibition in the range 38-96%. The most effective substituent in position 2, 4 or 7 of the 1,8-naphthyridine nucleus seem to be the piperidinyl group.  相似文献   
1000.
We present the most comprehensive comparison to date of the predictive benefit of genetics in addition to currently used clinical variables, using genotype data for 33 single‐nucleotide polymorphisms (SNPs) in 1,547 Caucasian men from the placebo arm of the REduction by DUtasteride of prostate Cancer Events (REDUCE®) trial. Moreover, we conducted a detailed comparison of three techniques for incorporating genetics into clinical risk prediction. The first method was a standard logistic regression model, which included separate terms for the clinical covariates and for each of the genetic markers. This approach ignores a substantial amount of external information concerning effect sizes for these Genome Wide Association Study (GWAS)‐replicated SNPs. The second and third methods investigated two possible approaches to incorporating meta‐analysed external SNP effect estimates – one via a weighted PCa 'risk' score based solely on the meta analysis estimates, and the other incorporating both the current and prior data via informative priors in a Bayesian logistic regression model. All methods demonstrated a slight improvement in predictive performance upon incorporation of genetics. The two methods that incorporated external information showed the greatest receiver‐operating‐characteristic AUCs increase from 0.61 to 0.64. The value of our methods comparison is likely to lie in observations of performance similarities, rather than difference, between three approaches of very different resource requirements. The two methods that included external information performed best, but only marginally despite substantial differences in complexity.  相似文献   
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