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71.
Aprilianto E. Wiria Firdaus Hamid Linda J. Wammes Margaretta A. Prasetyani Olaf M. Dekkers Linda May Maria M. M. Kaisar Jaco J. Verweij Bruno Guigas Felix Partono Erliyani Sartono Taniawati Supali Maria Yazdanbakhsh Johannes W. A. Smit 《PloS one》2015,10(6)
Objective
Given that helminth infections have been shown to improve insulin sensitivity in animal studies, which may be explained by beneficial effects on energy balance or by a shift in the immune system to an anti-inflammatory profile, we investigated whether soil-transmitted helminth (STH)-infected subjects are more insulin sensitive than STH-uninfected subjects.Design
We performed a cross-sectional study on Flores island, Indonesia, an area with high prevalence of STH infections.Methods
From 646 adults, stool samples were screened for Trichuris trichiura by microscopy and for Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale, and Strongyloides stercoralis by qPCR. No other helminth was found. We collected data on body mass index (BMI, kg/m2), waist-to-hip ratio (WHR), fasting blood glucose (FBG, mmol/L), insulin (pmol/L), high sensitive C-reactive protein (ng/ml) and Immunoglobulin E (IU/ml). The homeostatic model assessment for insulin resistance (HOMAIR) was calculated and regression models were used to assess the association between STH infection status and insulin resistance.Results
424 (66%) participants had at least one STH infection. STH infected participants had lower BMI (23.2 vs 22.5 kg/m2, p value = 0.03) and lower HOMAIR (0.97 vs 0.81, p value = 0.05). In an age-, sex- and BMI-adjusted model a significant association was seen between the number of infections and HOMAIR: for every additional infection with STH species, the HOMAIR decreased by 0.10 (p for linear trend 0.01). This effect was mainly accounted for by a decrease in insulin of 4.9 pmol/L for every infection (p for trend = 0.07).Conclusion
STH infections are associated with a modest improvement of insulin sensitivity, which is not accounted for by STH effects on BMI alone. 相似文献72.
73.
Shahverdi AR Abdolpour F Monsef-Esfahani HR Farsam H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):528-530
A simple TLC bioautographic method was developed for detection of antibiotic resistance reversal agents. In this study, the retention factor values of the components of some essential oils not previously shown to have any antibacterial activity were evaluated on nitrofurantoin supplemented agar media. The active component of Artemisia annua, Artemisia dracunculus and Eucalyptus globulus essential oils was piperitone which increased the antibacterial activity of nitrofurantoin against Enterobacter cloacae. Piperitone was not detected in the essential oil of Humulus lupulus and we could not observe any clear areas in this bioautographic method. 相似文献
74.
75.
Hamid Mohammadi Sandra Alaniz Zia Banihashemi Josep Armengol 《Journal of Phytopathology》2009,157(10):642-645
Eight Cylindrocarpon isolates recovered from the trunk bases of 10-year-old grapevines showing decline symptoms from two vineyards in Bavanat (Fars province, south-western Iran) were studied. Based on phenotypical characteristics, mating experiments and molecular data, they were identified as Cylindrocarpon liriodendri. Pathogenicity was confirmed with selected isolates inoculated into 8-month-old dormant rooted cuttings of grapevine rootstock cv. 110 Richter. This is the first report of C. liriodendri causing black foot disease of grapevines in Iran. 相似文献
76.
Hamid Forootanfar Mojtaba Shakibaie Zahra Bagherzadeh Marzieh Aghaie-Khozani Nastaran Nafissi-Varcheh Hamid Reza Monsef-Esfahani Mohammad Ali Faramarzi 《Journal of applied phycology》2013,25(1):51-57
The present study aimed at evaluating the ability of some isolated cyanobacterial and microalgal strains for the removal of ρ-chlorophenol (ρ-CP), an environmentally harmful contaminant. To identify the most efficient species, a screening program was carried out using 15 microalgal and cyanobacterial strains. Among them, Tetraselmis suecica was able to remove 67 % of the ρ-chlorophenol at an initial concentration of 20 mg L?1 from the medium within a 10-day period. The efficacy of the process was dependent on the ρ-chlorophenol concentration. At concentrations above 60 mg L?1 of the pollutant, no removal was observed due to the inhibitory effect of ρ-chlorophenol on the T. suecica cells. The effect of cell immobilization in alginate beads on T. suecica removal capacity was also examined. Using this technique, the removal efficacy for the initial ρ-CP concentration of 20 mg L?1 increased up to 94 %. 相似文献
77.
In this study, we examined the mechanistic insights of folate reabsorption during alcoholism, considering enhanced renal excretion
as one of the major contributing factors to alcohol-induced folate deficiency. Male Wistar rats were fed 1g/kg body weight/day
ethanol (20% solution) orally for 3 months. The results on characterization of the folate transport system in renal basolateral
membrane (BLM) suggested it to be a carrier-mediated, acidic pH-dependent and saturable one. Chronic ethanol feeding decreased
the uptake mainly by increasing the K
m and decreasing the V
max of the transport process at the BLM surface. At the molecular level, reduced folate transport activity in renal tissue during
chronic ethanol ingestion was attributable to decreased expression of reduced folate carrier (RFC) and folate binding protein
(FBP). Antibodies against RFC protein revealed a parallel change in RFC expression in both brush border and BLM surfaces during
chronic alcoholism. Such findings highlight the role of downregulation of RFC and FBP expression and provide mechanistic insight
into the observed reduced folate transport efficiency at renal absorptive surfaces in alcoholism, which may result in low
blood folate levels commonly observed in alcoholics. 相似文献
78.
79.
80.
Feng ZP Hamid J Doering C Bosey GM Snutch TP Zamponi GW 《The Journal of biological chemistry》2001,276(19):15728-15735
We recently reported that amino acid residues contained within a putative EF hand motif in the domain III S5-H5 region of the alpha(1B) subunit affected the relative barium:calcium permeability of N-type calcium channels (Feng, Z. P., Hamid, J., Doering, C., Jarvis, S. E., Bosey, G. M., Bourinet, E., Snutch, T. P., and Zamponi, G. W. (2001) J. Biol. Chem. 276, 5726-5730). Since this region partially overlaps with residues previously implicated in block of the channel by omega-conotoxin GVIA, we assessed the effects of mutations in the putative EF hand domain on channel block by omega-conotoxin GVIA and the structurally related omega-conotoxin MVIIA. Both of the toxins irreversibly block the activity of wild type alpha(1B) N-type channels. We find that in addition to previously identified amino acid residues, residues in positions 1326 and 1332 are important determinants of omega-conotoxin GVIA blockade. Substitution of residue Glu(1332) to arginine slows the time course of development of block. Point mutations in position Gly(1326) to either arginine, glutamic acid, or proline dramatically decrease the time constant for development of the block. Additionally, in the G1326P mutant channel activity was almost completely recovered following washout. A qualitatively similar result was obtained with omega-conotoxin MVIIA, suggesting that common molecular determinants underlie block by these two toxins. Taken together the data suggest that residue Gly(1326) may form a barrier, which controls the access of peptide toxins to their blocking site within the outer vestibule of the channel pore and also stabilizes the toxin-channel interaction. 相似文献