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241.
Crude ethanolic extract, lignoid fraction and the purified compound yangambin were obtained from Ocotea duckei (Lauraceae) and their antileishmanial activity was tested against promastigote forms of Leishmania chagasi and Leishmania amazonensis cultivated in Schneider medium, supplemented with 20% of fetal bovine serum. All substances presented antileishmanial activity with IC50 values of 135.7 microg/mL for the crude ethanolic extract, 26.5 microg/mL for the lignoid fraction and 49.0 microg/mL for yangambin on L. chagasi. For L. amazonensis the IC50 values were 143.7 microg/mL, 48.2 microg/mL and 64.9 microg/mL for the crude ethanolic extract, the lignoid fraction, and the purified compound yangambin, respectively. The crude ethanolic extract, lignoid fraction, and yangambin caused an inhibition higher than Glucantime, a reference drug used for the treatment of leishmaniasis.  相似文献   
242.
As significant improvements in volumetric antibody productivity have been achieved by advances in upstream processing over the last decade, and harvest material has become progressively more difficult to recover with these intensified upstream operations, the segregation of upstream and downstream processing has remained largely unchanged. By integrating upstream and downstream process development, product purification issues are given consideration during the optimization of upstream operating conditions, which mitigates the need for extensive and expensive clearance strategies downstream. To investigate the impact of cell culture duration on critical quality attributes, CHO-expressed IgG1 was cultivated in two 2 L bioreactors with samples taken on days 8, 10, 13, 15, and 17. The material was centrifuged, filtered and protein A purified on a 1 ml HiTrap column. Host cell protein (HCP) identification by mass spectrometry (MS) was applied to this system to provide insights into cellular behavior and HCP carryover during protein A purification. It was shown that as cultivation progressed from day 8 to 17 and antibody titer increased, product quality declined due to an increase in post-protein A HCPs (from 72 to 475 peptides detected by MS) and a decrease in product monomer percentage (from 98% to 95.5%). Additionally, the MS data revealed an increase in the abundance of several classes of post-protein A HCPs (e.g., stress response proteins and indicators of cell age), particularly on days 15 and 17 of culture, which were associated with significant increases in total overall HCP levels. This provides new insight into the specific types of HCPs that are retained during mAb purification and may be used to aid process development strategies.  相似文献   
243.
The whistles of Irrawaddy dolphins (Orcaella brevirostris) from the waters of Matang, western Peninsular Malaysia are described. Duration, frequency and frequency modulation variables were measured from 163 whistles recorded using a broadband towed hydrophone. Irrawaddy dolphins produced whistles with a mean duration of 0.366 s (S.D. ± 0.217 s). The fundamental frequency of whistles extended from 3040 to 17,123 Hz with low levels of frequency modulation. These dolphins produced whistles that were comparable to those of conspecifics recorded from the waters of Kalimantan, but were generally different from the related Australian snubfin dolphin (O. heinsohni). They also differed from the whistles of the sympatric Indo-Pacific humpback dolphin (Sousa chinensis). Characteristics of Irrawaddy dolphin whistles may be useful in future passive acoustic monitoring studies to investigate differences in sympatric species and their habitat.  相似文献   
244.
Recombinant protein expression is a prerequisite for diverse investigations of proteins at the molecular level. For targets from Mycobacterium tuberculosis it is favorable to use M. smegmatis as an expression host, a species from the same genus. In the respective shuttle vectors, target gene expression is controlled by the complex tetra‐cistronic acetamidase regulon. As a result, the size of those vectors is large, rendering them of limited use, especially when the target proteins are expressed from multi‐cistronic operons. Therefore, in the current work we present a versatile new expression vector in which the acetamidase regulon has been minimized by deleting the two genes amiD and amiS. We assessed the functional properties of the resulting vector pMyCA and compared it with those of the existing vector pMyNT that contains the full‐length acetamidase regulon. We analyzed the growth features and protein expression patterns of M. smegmatis cultures transformed with both vectors. In addition, we created mCherry expression constructs to spectroscopically monitor the expression properties of both vectors. Our experiments showed that the minimized vector exhibited several advantages over the pMyNT vector. First, the overall yield of expressed protein is higher due to the higher yield of bacterial mass. Second, the heterologous expression was regulated more tightly, offering an expression tool for diverse target proteins. Third, it is suitable for large multi‐protein complexes that are expressed from multi‐cistronic operons. Additionally, our results propose a new understanding of the regulation mechanism of the acetamidase regulon with the potential to construct more optimized vectors in the future.  相似文献   
245.
Substance use is a major cause of disability globally. This has been recognized in the recent United Nations Sustainable Development Goals (SDGs), in which treatment coverage for substance use disorders is identified as one of the indicators. There have been no estimates of this treatment coverage cross‐nationally, making it difficult to know what is the baseline for that SDG target. Here we report data from the World Health Organization (WHO)'s World Mental Health Surveys (WMHS), based on representative community household surveys in 26 countries. We assessed the 12‐month prevalence of substance use disorders (alcohol or drug abuse/dependence); the proportion of people with these disorders who were aware that they needed treatment and who wished to receive care; the proportion of those seeking care who received it; and the proportion of such treatment that met minimal standards for treatment quality (“minimally adequate treatment”). Among the 70,880 participants, 2.6% met 12‐month criteria for substance use disorders; the prevalence was higher in upper‐middle income (3.3%) than in high‐income (2.6%) and low/lower‐middle income (2.0%) countries. Overall, 39.1% of those with 12‐month substance use disorders recognized a treatment need; this recognition was more common in high‐income (43.1%) than in upper‐middle (35.6%) and low/lower‐middle income (31.5%) countries. Among those who recognized treatment need, 61.3% made at least one visit to a service provider, and 29.5% of the latter received minimally adequate treatment exposure (35.3% in high, 20.3% in upper‐middle, and 8.6% in low/lower‐middle income countries). Overall, only 7.1% of those with past‐year substance use disorders received minimally adequate treatment: 10.3% in high income, 4.3% in upper‐middle income and 1.0% in low/lower‐middle income countries. These data suggest that only a small minority of people with substance use disorders receive even minimally adequate treatment. At least three barriers are involved: awareness/perceived treatment need, accessing treatment once a need is recognized, and compliance (on the part of both provider and client) to obtain adequate treatment. Various factors are likely to be involved in each of these three barriers, all of which need to be addressed to improve treatment coverage of substance use disorders. These data provide a baseline for the global monitoring of progress of treatment coverage for these disorders as an indicator within the SDGs.  相似文献   
246.
247.

Background

Alcohol, tobacco, and illegal drug use cause considerable morbidity and mortality, but good cross-national epidemiological data are limited. This paper describes such data from the first 17 countries participating in the World Health Organization''s (WHO''s) World Mental Health (WMH) Survey Initiative.

Methods and Findings

Household surveys with a combined sample size of 85,052 were carried out in the Americas (Colombia, Mexico, United States), Europe (Belgium, France, Germany, Italy, Netherlands, Spain, Ukraine), Middle East and Africa (Israel, Lebanon, Nigeria, South Africa), Asia (Japan, People''s Republic of China), and Oceania (New Zealand). The WHO Composite International Diagnostic Interview (CIDI) was used to assess the prevalence and correlates of a wide variety of mental and substance disorders. This paper focuses on lifetime use and age of initiation of tobacco, alcohol, cannabis, and cocaine. Alcohol had been used by most in the Americas, Europe, Japan, and New Zealand, with smaller proportions in the Middle East, Africa, and China. Cannabis use in the US and New Zealand (both 42%) was far higher than in any other country. The US was also an outlier in cocaine use (16%). Males were more likely than females to have used drugs; and a sex–cohort interaction was observed, whereby not only were younger cohorts more likely to use all drugs, but the male–female gap was closing in more recent cohorts. The period of risk for drug initiation also appears to be lengthening longer into adulthood among more recent cohorts. Associations with sociodemographic variables were consistent across countries, as were the curves of incidence of lifetime use.

Conclusions

Globally, drug use is not distributed evenly and is not simply related to drug policy, since countries with stringent user-level illegal drug policies did not have lower levels of use than countries with liberal ones. Sex differences were consistently documented, but are decreasing in more recent cohorts, who also have higher levels of illegal drug use and extensions in the period of risk for initiation.  相似文献   
248.
The biological loading of viable, cultivable airborne microbes (heterotrophic bacteria, actinobacteria and fungi) in 6 size fractions as well as the three different fractions of respirable particulate matter (PM1, PM2.5 and PM10) and their relationship to meteorological conditions were studied in the ambient air due to health-related interests. An Andersen six stage viable particle impactor and a MAS 100 sampler were used for microbial measurements. 82 measurements were performed at three different periods (41 days) at a suburban, residential site in the city of Chania (Crete, Greece) during the period from April 2008 to June 2009. The concentrations of the viable, cultivable airborne microbes (bioaerosols) as well as of the PM1, PM2.5 and PM10 were highly variable during the whole measurement period. Among the airborne microbes, fungi presented the most abundant taxonomic group in the ambient air. A characteristic profile of the mean size distribution of biological loading in different PM fractions was obtained for every measured microbial taxonomic group. Although, the highest concentrations of the airborne fungi and actinobacteria were determined at aerodynamic diameters between 2.1 and 3.3 μm, a nearly equal distribution of the mean concentrations of the airborne heterotrophic bacteria was observed in the six different size fractions. However, two small maxima were observed at the airborne heterotrophic bacteria distribution, one at the fraction with aerodynamic diameters between 1.1 and 2.1 μm, and at other at the coarse fraction with aerodynamic diameter larger than 7 μm. A considerable part of the airborne microbes Cycloheximide per mL of growth medium of bacteriwere resistant to drugs. Between 10 and 40 % of the viable, cultivable airborne microbes were resistant to low concentrations of drugs (5–10 μg of Streptomycin or a or fungi, respectively). Furthermore, multiple linear regression of the data showed that the variation in fungi concentrations depends on the variation in PM10 mass concentration, PM1 number concentration, relative humidity and solar radiation. Likewise, the concentration of heterotrophic bacteria was found proportional to the values of relative humidity and fungal concentration, whereas was negatively correlated to the solar radiation.  相似文献   
249.
Saponins have the potential to favorably modulate rumen fermentation, but there is generally a lack of the chemical structures associated with the described effects. The activity of extracts from Calendula officinalis and Saponaria officinalis in the rumen was evaluated in vitro. The S. officinalis root extract, reduced CH4 production by 8.5% and increased total VFA concentration by 25.2%. C. officinalis and S. officinalis root extracts and the S. officinalis aerial part extract decreased the acetate to propionate ratio from 8.6 to 17.4%, according to the extract. An HPLC-ELSD analysis indicated that the saponin content ranged from 43.6 to 57.6?mg/g of dry matter (DM) in the C. officinalis extracts and from 224.0 to 693.8?mg/g of DM in the S. officinalis extracts, expressed as the hederacoside C equivalent. Identification of the saponin compounds present in the extracts by HPLC–MSn suggested that the saponin profile modulated the biological activities, showing the importance of determining the structure of saponins when evaluating extracts.  相似文献   
250.
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