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41.
Summary Glycolipids should have potential effects as antitumor agents. However, very few studies have examined this property of digalactosyl diacylglycerol (DGDG) and sulfoquinovosyl diacylglycerol (SQDG) on colon cancer cells. Cell viability was determined every 24 h with sodium 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium dye reduction assay up to 72 h. Alkaline phosphatase activity was measured for assessing cell differentiation. Apoptosis was tested with enzyme-linked immunosorbent assay analysis. Growth of Caco-2 cells was inhibited apparently at 48 h after addition of SQDG and at 72 h with DGDG. Alkaline phosphatase activity of Caco-2 cells obviously increased in combination with DGDG or SQDG and sodium butyrate (NaBT) at 72 h, indicating that DGDG and SQDG enhanced cell differentiation induced with NaBT. An increased enrichment factor was found when the cell was treated in combination with DGDG or SQDG and NaBT. These results strongly suggest that DGDG and SQDG should be considered as the leading compounds of potentially useful colon cancer chemotherapy agents when NaBT is combined.  相似文献   
42.
We aimed to detect Mycoplasma hyopneumoniae from the air of selected farms through air filtration-based air sampling using polymerase chain reaction (PCR). Air samples were collected at different locations inside and outside of pig farm rooms on polyethersulfone membrane (0.22 μm), and the presence of M. hyopneumoniae DNA was analyzed by PCR. Furthermore, nasal swab and blood samples were collected from 336 pigs in the same air sampled rooms and were analyzed by PCR and IDEXX ELISA, respectively. The suitability of the air sampling method was validated with analysis of an artificially induced aerosolized avirulent M. hyopneumoniae in an enclosed box showing PCR-positive results. M. hyopneumoniae was detected from air sample of pig farm rooms using PCR. Although the probability of an airborne M. hyopneumoniae causing an infection is not yet confirmed, air sampling PCR results could serve as a tool to assess the spread of M. hyopneumoniae by bioaerosols and the infection dynamics in a herd and between herds.  相似文献   
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International Journal of Peptide Research and Therapeutics - Overexpression of ERBBB family of receptors (ERBB1, ERBB2, ERBB3 and ERBB4) has been found to be hyper-activated in a number of...  相似文献   
44.
Plant and Soil - The major factors controlling the soil methane (CH4) concentration and CH4 emissions of various plant (mainly wetland) species were identified. Five plant species (Oryza sativa,...  相似文献   
45.
Wetlands Ecology and Management - Bangladesh has the single largest tract of naturally growing mangrove forest as well as the world’s largest manmade mangrove forest on newly accreted land in...  相似文献   
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We recently demonstrated that endogenous abscisic acid (ABA) is involved in methyl jasmonate (MeJA)-induced stomatal closure in Arabidopsis thaliana. In this study, we investigated whether endogenous ABA is involved in MeJA-induced reactive oxygen species (ROS) and nitric oxide (NO) production and cytosolic alkalization in guard cells using an ABA-deficient Arabidopsis mutant, aba2-2, and an inhibitor of ABA biosynthesis, fluridon (FLU). The aba2-2 mutation impaired MeJA-induced ROS and NO production. FLU inhibited MeJA-induced ROS production in wild-type guard cells. Pretreatment with 0.1 μM ABA, which does not induce stomatal closure in the wild type, complemented the insensitivity to MeJA of the aba2-2 mutant. However, MeJA induced cytosolic alkalization in both wild-type and aba2-2 guard cells. These results suggest that endogenous ABA is involved in MeJA-induced ROS and NO production but not in MeJA-induced cytosolic alkalization in Arabidopsis guard cells.  相似文献   
49.

Background

The study was conducted to evaluate the in vitro antimicrobial activity, cytotoxic, and membrane stabilization activities, and in vivo antiemetic and antipyretic potentials of ethanolic extract, n-hexane and ethyl acetate soluble fractions of Spilanthes paniculata leaves for the first time widely used in the traditional treatments in Bangladesh.

Results

In antipyretic activity assay, a significant reduction (P < 0.05) was observed in the temperature in the mice tested. At dose 400 mg/kg-body weight, the n-hexane soluble fraction showed the effect (36.7 ± 0.63°C ) as like as the standard (dose 150 mg/kg-body weight) after 5 h of administration. Extracts showed significant (P < 0.001) potential when tested for the antiemetic activity compared to the standard, metoclopramide. At dose 50 mg/kg-body weight, the standard showed 67.23% inhibition, whereas n-hexane and ethyl acetate soluble fractions showed 37.53% and 24.93% inhibition of emesis respectively at dose 400 mg/kg-body weight. In antimicrobial activity assay, the n-hexane soluble fraction (400 μg/disc) showed salient activity against the tested organisms. It exerts highest activity against Salmonella typhi (16.9 mm zone of inhibition); besides, crude, and ethyl acetate extracts showed resistance to Bacillus cereus and Bacillus subtilis, and Vibrio cholera respectively. All the extracts were tested for lysis of the erythrocytes. At the concentration of 1mg/ml, ethanol extract, and n-hexane and ethyl acetate soluble fractions significantly inhibited hypotonic solution induced lysis of the human red blood cell (HRBC) (27.406 ± 3.57, 46.034 ± 3.251, and 30.72 ± 5.679% respectively); where standard drug acetylsalicylic acid (concentration 0.1 mg/ml) showed 77.276 ± 0.321% inhibition. In case of heat induced HRBC hemolysis, the plant extracts also showed significant activity (34.21 ± 4.72, 21.81 ± 3.08, and 27.62 ± 8.79% inhibition respectively). In the brine shrimp lethality bioassay, the n-hexane fraction showed potent (LC50 value 48.978 μg/ml) activity, whereas ethyl acetate fraction showed mild (LC50 value 216.77 μg/ml) cytotoxic activity.

Conclusions

Our results showed that the n-hexane extract has better effects than the other in all trials. In the context, it can be said that the leaves of S. paniculata possess remarkable pharmacological effects, and justify its folkloric use as antimicrobial, antipyretic, anti-inflammatory, and antiemetic agent. Therefore, further research may be suggested to find possible mode of action of the plant part.  相似文献   
50.

Objectives

University students in general face multiple challenges, which may affect their levels of perceived stress and life satisfaction. Chinese students currently face specific strains due to the One-Child Policy (OCP). The aim of this study was to assess (1) whether the levels of perceived stress and studying-related life satisfaction are associated with only-child (OC) status after controlling for demographic and socio-economic characteristics and (2) whether these associations differ between Chinese and international students.

Materials and Methods

A cross-sectional health survey based on a self-administrated standardised questionnaire was conducted among 1,843 (1,543 Chinese, 300 international) students at two Chinese universities in 2010–2011. Cohen’s Perceived Stress Scale (PSS-14) and Stock and Kraemer’s Studying-related Life Satisfaction Scale were used to measure perceived stress and studying-related life satisfaction respectively. Multivariable logistic regression analyses were used to examine the associations of OC status with perceived stress and studying-related life satisfaction by sex for Chinese students and international students separately.

Results

The Chinese non-only-children (NOCs) were more likely to come from small cities. Multivariable regression models indicate that the Chinese NOCs were more stressed than OCs (OR = 1.39, 1.11–1.74) with a stronger association in men (OR = 1.48, 1.08–2.02) than women (OR = 1.26, 0.89–1.77). NOCs were also more dissatisfied than their OC fellows in the Chinese subsample (OR = 1.37, 1.09–1.73). Among international students, no associations between OC status and perceived stress or studying-related life satisfaction were found.

Conclusions

To promote equality between OCs and NOCs at Chinese universities, the causes of more stress and less studying-related life satisfaction among NOCs compared to OCs need further exploration.  相似文献   
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