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71.
A series of sila‐organosulphur compounds containing 1,2,3‐triazole cores were screened for their cytotoxic activity on human breast cancer cell line MCF‐7. Most of the tested compounds exhibited moderate‐to‐good activity against the cancer cells. Especially, the compound 4‐((2‐(trimethylsilyl)ethynylthio)methyl)‐1‐benzyl‐1H‐1,2,3‐triazole ( 3a) from series of sila‐substituted thioalkyne 1,2,3‐triazoles (STATs) and the compounds 3‐(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)‐1‐mercapto‐1,1‐bis(trimethylsilyl)propane‐2‐thione ( 4a) and 1‐mercapto‐1,1‐bis(trimethylsilyl)‐3‐(1‐phenethyl‐1H‐1,2,3‐triazol‐4‐yl)propane‐2‐thione ( 4e) from series of sila‐substituted mercapto‐thione 1,2,3‐triazoles (SMTTs) exhibited promising cytotoxicity against MCF‐7 with IC50 values of 35.17, 32.63 and 30.3 μg/mL, respectively. In addition, the possible mechanisms for inhibition of cell growth and induction of apoptotic cell death were explored by DAPI staining, cell cycle analysis and qRT‐PCR. The synthetic compounds were evaluated for their in vitro antibacterial activities, and as a result, the most prominent effects were observed for 3e and 4e . Especially, 3e was found to be quite active against all the tested strains with the MIC values ranging from 15 to 62 μg/mL, except P. aeruginosa. The results of the time‐kill assay suggested that the compound of 3e completely inhibited the growth of both gram‐negative bacteria, A. baumannii, and gram‐positive bacteria, S. aureus. In addition, SEM analysis confirmed morphostructural damage of the bacteria. Our findings could be applicable for developing dual‐targeting anticancer/antibacterial therapeutics.  相似文献   
72.
Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided.  相似文献   
73.
Among the legume foods, soy proteins are finding increased use in human diets. Hence, selected aspects of dietary mineral absorption and availability in reference to soy proteins are reviewed, with particular attention being given to the human nutritional context. Data from animal feeding studies are considered first as a basis for indicating the value, as well as limitations, of data from animal bioassays on mineral absorption as they may relate directly to human feeding. It is apparent that the availability of zinc and iron in soy-based diets given to animals is variable and it is difficult to draw generalized conclusions about legumes and mineral absorption in reference to man. The limited data obtained in human metabolic studies are reviewed and they lead to the conclusion that well-processed soy concentrates and isolates do not impair zinc absorption or nutriture. The effects of diets based on significant intakes of soy foods on the absorption of iron are still unclear although the major available evidence does not suggest significant untoward consequences of increased soy-protein intake on body iron nutriture. This problem deserves more attention, and not only with respect to iron but also other trace elements for which data in human subjects are limited or entirely lacking. Preliminary results of studies of MIT experiments, in which stable isotope probes are being developed to quantify mineral bioavailability, arc reviewed as a basis for indicating possible novel and useful approaches for exploring quantitative aspects of nutrient bioavailability in diets consumed directly by man.  相似文献   
74.
Nasojejunal feeding tubes are being used at an increased frequency, but it is not without complications that could be life-threatening. We report two cases of pneumothorax following small-bore feeding tube insertion into the pleural cavity, resulting in pneumothorax. We further discuss the potential measures that can be taken to prevent and treat this serious complication.  相似文献   
75.
Increased reliance of urban populations on Rio Grande water has necessitated an expanded microbial surveillance of the river to help identify and evaluate sources of human pathogens, which could pose a public health risk. The objectives of this study were to investigate microbial and chemical water quality in Rio Grande water and to perform risk assessment analyses for Cryptosporidium. No oocysts in any of the ten-litre samples were detected. However, the limit of detection in the water samples ranged between 20 and 200 oocysts/100 L. The limits of detection obtained in this study would result in one to two orders of magnitude higher risk of infection for Cryptosporidium than the U.S.EPA annual acceptable risk level of 10(-4). The bacterial data showed the significance of animal farming and raw sewage as sources of fecal pollution. Male specific and somatic coliphages were detected in 52% (11/21) and 62% (24/39) of the samples, respectively. Somatic coliphages were greater by one order of magnitude, and were better correlated with total (r2 = 0.6801; p < or = 0.05) and fecal coliform bacteria (r2 = 0.7366; p < or = 0.05) than male specific coliphages. The dissolved organic carbon (DOC) and specific ultraviolet absorbance (SUVA) values ranged 2.58-5.59mg/L and 1.23-2.29 m(-1) (mg/I)(-1), respectively. Low SUVA values of raw water condition make it difficult to remove DOC during physical and chemical treatment processes. The microbial and chemical data provided from this study can help drinking water utilities to maintain balance between greater microbial inactivation and reduced disinfection by-products (DBPs) formation.  相似文献   
76.
ABSTRACT

This study reports on the characteristics, sources, and health risks of atmospheric PM10-bound heavy metals (HMs) on citizenship living in different regions of Ahvaz, Southwest of Iran were investigated during 2016–2017. A total of 84 samples were analyzed from different regions: (S1) industrial, (S2) high traffic, and (S3) residential. Blood samples were collected from people who came to the east health center of Ahvaz. High volume air samplers, equipped with quartz fiber filters (8?×?10) were utilized for sampling in this study. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was also used for HMs. Risk assessment and hazard index of these pollutants were estimated, using USEPA’s exposure parameters. Based on the results, the highest and the lowest concentration of HM were observed in industrial and residential areas. Blood’s HMs concentration for chromium (Cr), nickel (Ni), lead (Pb), and zinc (Zn) were 2.932, 4.199, 8.425, and 71.2?μg/dL, respectively. In conclusion, increasing exposure concentration of HMs would have a significant potential for increased cancer and risk of diseases. The results of this study show that increasing exposure concentration to HM in the studied scenarios have a significant potential for generating different health endpoints, although exposing to HMs led to generating diseases in individuals particularly in polluted and populated districts; so, environmental measures should be considered by urban air authorities to mitigate the concentration of these pollutants in ambient air.  相似文献   
77.
Cromolyn sodium (CS) was spray dried under constant operation conditions from different water to ethanol feed ratios (50:50-0:100). The spray dried CS samples were characterized for their physicochemical properties including crystallinity, particle size distribution, morphology, density, and water/ethanol content. To determine quantitatively the crystallinity of the powders, an X-ray diffraction (XRD) method was developed using samples with different crystallinity prepared by physical mixing of 100% amorphous and 100% crystalline CS materials. The aerodynamic behavior of the CS samples was determined using an Andersen Cascade Impactor (ACI) with a Spinhaler at an air flow of 60 L/min. Binary mixtures of each spray dried CS powder and Pharmatose 325, a commercial alpha-lactose monohydrate available for DPI formulations, were prepared and in vitro aerosol deposition of the drug from the mixtures was analyzed using ACI to evaluate the effect of carrier on deposition profiles of the spray dried samples. CS spray dried from absolute ethanol exhibited XRD pattern characteristic for crystalline materials and different from patterns of the other samples. The crystallinity of spray dried CS obtained in the presence of water varied from 0% to 28.37%, depending on the ratio of water to ethanol in the feed suspensions. All samples presented different particle size, water/ethanol content, and bulk density values. CS particles spray dried from absolute ethanol presented uniform elongated shape whereas the other samples consisted mainly of particles with irregular shape. Overall, fine particle fraction increased significantly (p < 0.01) with decreasing d50% and water and ethanol content of spray dried CS samples. Significant difference (p < 0.01) in deposition profiles of the drug were observed between corresponding carrier free and carrier blended formulations. The difference in deposition profiles of CS aerosolized from various spray dried samples were described according to the particle size, shape, and water/ethanol contents of the powders. The results of this study indicate that enhanced aerosol performance of CS can be obtained by spray drying of the drug from suspensions containing > or = 87.5% v/v ethanol.  相似文献   
78.
Methamphetamine, a highly addictive psychostimulant drug, is widely used by substance users who are not motivated to undergo treatment throughout the world, including Iran. This research was conducted to evaluate the effectiveness of a brief home-based social work motivational intervention (HSWMI) to encourage male methamphetamine users to participate in a treatment program. Method: Fifty-six unmotivated male methamphetamine users participated in a randomized controlled trial. The case group received the HSWMI in addition to the usual consulting services in the clinic; the control group just received the usual consulting services. Data were collected 7 and 90 days after the intervention to evaluate participation and retention in a treatment program. Data were analyzed using the chi-square test. Results: Drug users with a mean age of 32.55 years and mean duration of drug use of 7.73 years, participated in the case (n = 28) and control (n = 28) groups. The case group participated in treatment programs significantly more than the control group and the retention rate for the case group was significantly higher than for the control group. Conclusion: This brief HSWMI was effective to increase the motivation of methamphetamine users to participate and remain in treatment programs. This intervention can be implemented by social workers in substance use treatment centers.  相似文献   
79.
In the present study, the possible effect of nitric oxide agents injected into the nucleus accumbens (NAc) in the presence or absence of nicotine on morphine state-dependent memory in adult male Wistar rats was investigated. As a model of memory, a step-through type inhibitory avoidance task was used. Post-training injection of morphine (4 and 6 mg/kg) dose dependently induced the impairment of memory retention. Administration of morphine (4 and 6 mg/kg) before retention induced state-dependent retrieval of the memory acquired under post-training morphine (6 mg/kg) influence. Injection of nicotine before retention (0.25 and 0.5 mg/kg) alone and nicotine (0.1, 0.25 and 0.5 mg/kg) plus an ineffective dose of morphine (2 mg/kg) reversed the post-training morphine-induced memory impairment. The amnesia elicited by morphine (6 mg/kg) was also prevented by pre-retention intra-NAc administration of a nitric oxide synthase (NOS) inhibitor, l-NAME (0.24 μg/rat, intra-NAc). Interestingly, an ineffective dose of nicotine (0.1 mg/kg) in combination with low doses of l-NAME (0.06 and 0.12 μg/rat, intra-NAc) synergistically improved memory performance impaired by morphine given after training. It is important to note that intra-NAc administration of l-NAME before retention impaired memory retrieval by itself. In contrast, pre-retention administration of l-arginine, a nitric oxide (NO) precursor (0.25 and 0.5 μg/rat, intra-NAc), which had no effect alone, prevented the nicotine reversal of morphine effect on memory. The results suggest a possible role for nitric oxide of nucleus accumbens in the improving effect of nicotine on the morphine-induced amnesia and morphine state-dependent memory.  相似文献   
80.
OBJECTIVE: To compare the efficacy of seven pyrethroid insecticides for impregnation of mosquito nets, six currently recommended by WHO and one candidate (bifenthrin), under laboratory conditions. METHODS: Tests were conducted using pyrethroid-susceptible and pyrethroid-resistant strains of Anopheles gambiae and Culex quinquefasciatus. Knock-down effect, irritancy and mortality were measured using standard WHO cone tests. Mortality and blood-feeding inhibition were also measured using a baited tunnel device. FINDINGS: For susceptible A. gambiae, alpha-cypermethrin had the fastest knock-down effect. For resistant A. gambiae, the knock- down effect was slightly slower with alpha-cypermethrin and much reduced following exposure to the other insecticides, particularly bifenthrin and permethrin. For susceptible C. quinquefasciatus, the knock-down effect was significantly slower than in A. gambiae, particularly with bifenthrin, and no knock-down effect was observed with any of the pyrethroids against the resistant strain. Bifenthrin was significantly less irritant than the other pyrethroids to susceptible and resistant A. gambiae but there was no clear ranking of pyrethroid irritancy against C. quinquefasciatus. In tunnels, all insecticides were less toxic against C. quinquefasciatus than against A. gambiae for susceptible strains. For resistant strains, mortality was significant with all the pyrethroids with A. gambiae but not with C. quinquefasciatus. Inhibition of blood-feeding was also high for susceptible strains of both species and for resistant A. gambiae but lower for resistant C. quinquefasciatus; bifenthrin had the greatest impact. CONCLUSIONS: Efficacy for impregnation of mosquito nets against A. gambiae was greatest with alpha-cypermethrin. Bifenthrin is likely to have a significant comparative advantage over other pyrethroids in areas with pyrethroid resistance because of its much stronger impact on the nuisance mosquito, C. quinquefasciatus, despite its slower knock-down effect and irritancy. Selection of pyrethroids for mosquito vector control and personal protection should take into account the different effects of these insecticides, the status of pyrethroid resistance in the target area, and the importance of nuisance mosquitoes, such as C. quinquefasciatus.  相似文献   
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