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81.
82.
Passiflora incarnata L. has been used as a medicinal plant in South America and Europe since the 16th century. Previous pharmacological studies focused mainly on the plant's sedative, anxiolytic, and anticonvulsant effects on the central nervous system and its supporting role in the treatment of addiction. The aim of the present study was to evaluate the behavioral and neurochemical effects of long‐term oral administration of P. incarnata. The passionflower extract (30, 100, or 300 mg/kg body weight/day) was given to 4‐week‐old male Wistar rats via their drinking water. Tests were conducted after 7 weeks of treatment. Spatial memory was assessed in a water maze, and the levels of amino acids, monoamines, and their metabolites were evaluated in select brain regions by high performance liquid chromatography (HPLC). We observed reduced anxiety and dose‐dependent improvement of memory in rats given passionflower compared to the control group. In addition, hippocampal glutamic acid and cortical serotonin content were depleted, with increased levels of metabolites and increased turnover. Thus, our results partially confirmed the proposed mechanism of action of P. incarnata involving GABAA receptors. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
83.
Diet plays a role in the onset and progression of metabolic disorders, including metabolic syndrome (MetS). We aimed to systematically review and conduct a quantitative meta-analysis of results from observational cross-sectional and prospective cohort studies on adherence to the Mediterranean dietary pattern and risk of MetS. Literature databases including PubMed, SCOPUS and EMBASE were searched from the beginning to May 2016. Eight cross-sectional and four prospective studies were included in this meta-analysis, accounting for a total of 33,847 individuals and 6342 cases of MetS. High adherence to the Mediterranean diet was associated with a risk of MetS (RR: 0.81, 95%CI: 0.71, 0.92). Regarding individual components of the MetS, the inverse associations were significant for waist circumference, blood pressure and low HDL-C levels. In conclusion, adoption of a Mediterranean dietary pattern was associated with lower risk of the MetS and it can be proposed for the primary prevention of the MetS.  相似文献   
84.
The miniCD4 M48U1 was formulated into thermosensitive and mucoadhesive pluronic® hydrogels as anti-HIV-1 microbicide. The release kinetics of M48U1 from F127/HPMC (20/1 wt%) and F127/F68/HPMC (22.5/2.5/1 wt%) studied during 24 h by using Franz diffusion cells showed that HEC hydrogel (1.5 wt%) used as control released 93% of the peptide, while about 25% of M48U1 remained in pluronic® hydrogels. The formulation of M48U1 in pluronic® hydrogels ensures a local delivery because no diffusion of the peptide was detected through vaginal Cynomolgus macaque mucosa using Ussing chamber. Finally, toxicological studies showed no significant difference in the HeLa cell viability of the pluronic® hydrogels in comparison with HEC and phosphate buffer saline.  相似文献   
85.
Context: The main source of bufadienolides is toad venom; however, plants such as members of Kalanchoe Adans. (Crassulaceae) genus may also synthesize these bioactive substances.

Objective: This is the first study on antioxidant effects and cytotoxicity of bufadienolide-rich fraction isolated from Kalanchoe daigremontiana Raym.-Hamet & H. Perrier.

Materials and methods: The methanolic fraction was extracted from the plant roots and contained 0.48?mg bufadienolides/mg of dry mass (11α,19-dihydroksytelocinobufagin, bersaldegenin-1-acetate, bersaldegenin-1,3,5-orthoacetate, 19-(acetyloxy)-3β,5β,11α,14-tetrahydroxyl-12-oxo-bufa-20,22-dienolide and 19-(acetyloxy)-1β,3β,5β,14-tetrahydroxyl-bufa-20,22-dienolide, mainly). The cytotoxicity of K. daigremontiana fraction was evaluated in an in vitro experimental model of blood platelets. The viability of blood platelets was determined on the basis of a release of lactate dehydrogenase.

Results: The fraction scavenged DPPH? radicals, with EC50 of 21.80?μg/mL. Studies on an experimental model of blood plasma under peroxynitrite-induced oxidative stress revealed that the plant preparation had moderate antioxidant properties. Levels of 3-nitrotyrosine and thiol groups indicated that the protective effect of K. daigremontiana was significant mainly for its concentration of 50?μg/mL. No effect was found in prevention of oxidation of low-molecular plasma thiols (glutathione, cysteine and cysteinylglycine). Simultaneously, measurements of lipid hydroperoxides and thiobarbituric acid-reactive substances (TBARS) indicated that the examined fraction might be effective antioxidant at broader concentration range, that is 1–5 and 25–50?μg/mL for hydroperoxides and TBARS generation, respectively. No cytotoxicity was observed at the concentration range of 1–50?μg/mL.

Conclusions: Based on the obtained results, we suggest that antioxidant activity may additionally contribute to beneficial properties of K. daigremontiana-derived extracts.  相似文献   
86.
Bisphenol A (BPA), is present in a multitude of products, including food and water containers, food can linings, dentistry sealants, and thermal paper. BPA can induce the growth of human ovarian cancer cell lines. Reduction of adhesion and the initiation of metastasis are important events in cancer progression; therefore, this study investigated the effects of BPA (0.1–100 nM) on the migration of OVCAR-3 ovarian cancer cells and the expression levels of metalloproteinases (MMPs) and cadherins. The oestrogenic compound 17β-estradiol (40 nM) was used as a positive control for estrogenic properties of bisphenol A. BPA stimulated cell migration, and the effect of BPA was similar to that of 17β-estradiol. BPA-induced cell migration was accompanied by up-regulation of the migration-related factors MMP-2, MMP-9 and N-cadherin, but E-cadherin expression and activity was unaffected. The stimulatory effects of BPA on cell migration were abolished by pre-treatment of the cells with inhibitors of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase pathways (PI3K). In conclusion, the results presented here show that BPA induces OVCAR-3 cells migration by activating MAPK and PI3K/Akt signalling pathways.  相似文献   
87.
Short-chain fatty acids (SCFAs) are the product of the anaerobic intestinal bacterial fermentation of dietary fiber and resistant starch. An abnormal intestinal microbiota may cause a reduction in the production of SCFAs, which stimulate the development of intestinal epithelial cells, nourish enterocytes, influence their maturation and proper differentiation, reduce the pH, and are an additional source of energy for the host. There have been reports of the special role of SCFAs in the regulation of glucose and lipid metabolism during pregnancy. Aim: The aim of the study was to analyze the correlation of SCFAs with lipid and hepatic metabolism during pregnancy in relation to the body weight of pregnant women. Material and methods: This study was conducted in pregnant women divided into two groups: Obese (OW—overweight and obese women; n = 48) and lean (CG—control group; n = 48) individuals. The biochemical plasma parameters of lipid metabolism (TG, CH, LDL, HDL), inflammation (CRP), and liver function (ALT, AST, GGT) were determined in all of the subjects. SCFA analysis was performed in the stool samples to measure acetic acid (C 2:0), propionic acid (C 3:0), isobutyric acid (C 4:0 i), butyric acid (C 4:0 n), isovaleric acid (C 5:0 i) valeric acid (C 5:0 n), isocaproic acid (C 6:0 i), caproic acid (C 6:0 n), and heptanoic acid (C 7:0). Results: Statistically significant differences in the concentrations of C 3:0 and C 6:0 n were found between women in the OW group compared to the CG group. The other SCFAs tested did not differ significantly depending on BMI. The C 2:0, C 3:0, and C 4:0 n ratios showed differences in both OW and CG groups. In the OW group, no relationship was observed between the concentrations of the SCFAs tested and CRP, ALT, AST. A surprising positive relationship between C 5:0 n and all fractions of the tested lipids and branched C 5:0 with CHL, HDL, and LDL was demonstrated. In the OW group, HDL showed a positive correlation with C 3:0. However, lower GGT concentrations were accompanied by higher C 4:0 and C 5:0 values, and this tendency was statistically significant. Conclusions: The results of our research show that some SCFAs are associated with hepatic lipid metabolism and CRP concentrations, which may vary with gestational weight. Obesity in pregnancy reduces the amount of SCFAs in the stool, and a decrease in the level of butyrate reduces liver function.  相似文献   
88.
Background: Food addiction (FA) is a dysregulated eating pattern characterized by difficulties in controlling the intake of certain foods. There is an overlap in physical and mental health correlates of FA and post-traumatic stress disorder (PTSD). The purpose of this study was to examine sex differences in the rates of positive FA status in individuals with threshold/subthreshold PTSD, and to examine sex differences in the physical and mental health correlates of FA. Methods: Post-9/11 veterans/service members seeking PTSD treatment were recruited. Participants were diagnosed with PTSD via the administration of a clinical interview. FA status was determined using Modified Yale Food Addiction Scale-2, binary sex and body mass index were assessed with demographics questions. Results: Nearly half (43%) of the sample were women. There were no sex differences in the rates of FA, with an overall FA prevalence of 18%. There were no sex differences in FA symptom count in the whole sample (M = 1.63) or those with FA status (M = 6.21). Individuals with FA reported higher frequency of disordered eating, higher severity of PTSD, and depression symptoms. Conclusions: FA should be assessed in tandem with PTSD symptoms, as its prevalence in that sample is higher than in the general population, and it appears to affect both sexes at similar rates.  相似文献   
89.
Curcumin is one of the most frequently researched herbal substances; however, it has been reported to have a poor bioavailability and fast metabolism, which has led to doubts about its effectiveness. Curcumin has antioxidant and anti-inflammatory effects, and has demonstrated favorable health effects. Nevertheless, well-reported in vivo pharmacological activities of curcumin are limited by its poor solubility, bioavailability, and pharmacokinetic profile. The bidirectional interactions between curcumin and gut microbiota play key roles in understanding the ambiguity between the bioavailability and biological activity of curcumin, including its wider health impact.  相似文献   
90.
Antibiotic resistance of Staphylococcus-like organisms (STLO) isolated from a recreational sea beach located on the southern coast of the Baltic Sea was studied. The results of the present study showed that STLO inhabiting sand and seawater of the beach strongly differed in the resistance level to tested antibiotics. These microorganisms were most resistant to ampicillin, penicillin, oxytetracycline and susceptible to gentamicin, neomycin and streptomycin. Moreover, the level of antibiotic resistance among bacteria isolated from different parts of the beach also differed. Bacteria inhabiting the seawater, shoreline and the middle part of the beach were more antibiotic-resistant than bacteria isolated from the dune. The majority of bacteria inhabiting the seawater and sand were resistant to 3–8 antibiotics out of 12 tested in this study. Generally, there was no difference in antibiotic resistance between Staphylococcus-like organisms isolated from the surface and subsurface sand layers. STLO strains isolated from Ustka Beach were most resistant to β-lactam and tetracycline antibiotics, and most susceptible to aminoglycosides.  相似文献   
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