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Chronic alcohol (ethanol) abuse causes neuroinflammation and brain damage that can give rise to alcoholic dementia. Insightfully, Dr. Albert Sun was an early proponent of oxidative stress as a key factor in alcoholism-related brain deterioration. In fact, oxidative stress has proven to be critical to the hippocampal and temporal cortical neurodamage resulting from repetitive “binge” alcohol exposure in adult rat models. Although the underlying mechanisms are uncertain, our immunoelectrophoretic and related assays in binge alcohol experiments in vivo (adult male rats) and in vitro (rat organotypic hippocampal-entorhinal cortical slice cultures) have implicated phospholipase A2 (PLA2)-activated neuroinflammatory pathways, release of pro-oxidative arachidonic acid (20:4 ω6), and elevated oxidative stress adducts (i.e., 4-hydroxynonenal-protein adducts). Also, significantly increased by the binge alcohol treatments was aquaporin-4 (AQP4), a water channel enriched in astrocytes that, when augmented, may trigger brain (esp. cellular) edema and neuroinflammation; of relevance, glial swelling is known to provoke increased PLA2 activities or levels. Concomitant with PLA2 activation, the results have further implicated binge alcohol-elevated poly (ADP-ribose) polymerase-1 (PARP-1), an oxidative stress-responsive DNA repair enzyme linked to parthanatos, a necrotic-like neuronal death process. Importantly, supplementation of the brain slice cultures with docosahexaenoic acid (22:6 ω3) exerted potent suppression of the induced changes in PLA2 isoforms, AQP4, PARP-1 and oxidative stress footprints, and prevention of the binge alcohol neurotoxicity, by as yet unknown mechanisms. These neuroinflammatory findings from our binge alcohol studies and supportive rat binge studies in the literature are reviewed.  相似文献   

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Psoriasis is a chronic skin disease triggered by genetic, environment or other risk factors such as infection, drugs, stress, moisture, alcohol, and smoking. A major psoriasis susceptibility locus at 6p21.3 has been identified. Further studies found that HLA-DQA1*0201 allele was associated with psoriasis. However, there were few data exploring an association between the environmental factors and susceptibility genes. In this study, the samples of 189 patients with psoriasis and 333 healthy controls were collected with their consent and were carried on analysis through polymerase chain reaction sequence-specific primer (PCR-SSP) method. The proportion of male psoriasis patients engaging in the smoking and alcohol was much higher than that of the control group (P<0.005). The HLA-DQA1*0201 allele was present at significantly higher frequency in the patients with psoriasis (OR=4.25, P<1.0 x 10(-6)). Association was found between smoking, alcohol and HLA-DQA1*0201 in male patients with psoriasis (OR>6.91, P<1.0 x 10(-4)).  相似文献   

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The effects of sodium tetradecyl sulfate (STS), β-phenethyl alcohol (PEA), and p-nitrophenylglycerol (PNPG) on motility, swarming, flagellation, and growth of Proteus were examined. Growth-inhibitory concentrations (GIC) and swarming-inhibitory concentrations (SIC) were determined. A characterization of the swarming-inhibitory efficacy of these compounds was based on their GIC/SIC ratio and their concentration inhibition curves. Using the homologous series of sodium alkyl sulfates as a standard reference, we showed that PNPG was more effective than STS, which was the most effective of the homologous series. PEA was less effective than sodium decyl sulfate but more effective than sodium octyl sulfate. Motility tests in liquid medium and electron microscope investigations indicated that the modes of action of the three compounds, all of which effectively inhibit the swarming of Proteus, are different. Whereas STS and PEA inhibit swarming by inhibition of motility, PNPG seems to act on the swarming mechanism sensu strictori, without impairment of motility. STS immobilizes by inhibition of flagellum formation or by some lytic action on the flagella already synthesized. PEA acts by impairing flagellar function, but leaves the flagella morphologically intact.  相似文献   

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Ester Formation by Alcohol Acetyltransferase from Brewers’ Yeast   总被引:2,自引:0,他引:2  
Alcohol acetyltransferase responsible for the formation of acetate esters during beer fermentation was found to be localized at the cell membrane of brewers’ yeast. This cell membrane-bound enzyme was purified 120-fold by solubilization with Triton X-100, gel filtration on a Sepharose 6B column and chromatography on a DEAE-Sephadex A-50 column. The enzyme was most active at 30°C at pH 7 ? 8. It was least active against C3 alcohol among C1 ? C6 alcohols, and slightly more active against straight-chain alcohols than against branched-chain alcohols with the same carbon number. The enzyme was strongly inhibited by unsaturated fatty acids, heavy metal ions and sulfhydryl reagents.  相似文献   

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Protein kinase C (PKC) is a family of signal transducing enzymes that have been implicated in anesthetic preconditioning signaling cascade. Evidences are emerging that certain exogenous neuromodulators such as n-alkanols and general anesthetics can stimulate PKC activity by binding to regulatory C1A domain of the enzyme. However, the accurate binding sites in C1A domain as well as the molecular mechanism underlying binding-stimulated PKC activation still remain unelucidated. Here, we report a systematic investigation of the intermolecular interaction of human PKCδ C1A domain with its natural activator phorbol ester (PE) and co-activator dioleoylglycerol (DOG) as well as exogenous stimulators butanol, octanol and sevoflurane. The domain is computationally identified to potentially have three spatially vicinal ligand-binding pockets 1, 2 and 3, in which the pockets 1 and 2 have previously been determined as the binding sites of PE and DOG, respectively. Systematic cross-binding analysis reveals that long-chain octanol and DOG are well compatible with the flat, nonpolar pocket 2, where the nonspecific hydrophobic contacts and van der Waals packing are primarily responsible for the binding, while the general anesthetic sevoflurane prefer to interact with the rugged, polar pocket 3 through specific hydrogen bonds and electrostatic forces. Short-chain butanol appears to bind effectively none of the three pockets. In addition, the pocket 1 consists of two angled arms 1 and 2 that are also involved in pockets 2 and 3, respectively. Dynamics characterization imparts that binding of long-chain octanol and DOG to pocket 2 or binding of sevoflurane to pocket 3 can induce a conformational displacement in arm 1 or 2, thus further opening the included angle and enlarging pocket 1, which can improve the pocket 1-PE affinity via an allosteric mechanism, consequently stimulating the PE-induced PKCδ activation.  相似文献   

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Epidemiological data show that light-to-moderate drinkers, especially those over 50 years of age, are more healthy in every way than non-drinkers. Although the J-shaped all-cause mortality curves may indicate that small quantities of alcohol (for some age groups) can confer good health, researchers are beginning to realize that drinking habits also reflect far more powerful underlying risk factors such as socio-economic class, education and general ill-health. Epidemiologists, cardiologists, statisticians, public health experts and sociologists met at the Novartis Foundation in London in October 1997 to discuss this vexed question in light of the new clinical, biochemical and sociological data that have emerged in recent months. In the red corner, statisticians and sociologists, such as Professor Kaye Fillimore (Institute of Health and Ageing, San Francisco, CA, USA) showed that outdated, ineffectual questionnaires, unreliable reporting and poor statistical classification have probably vastly exaggerated the so-called `beneficial' effect of alcohol. Furthermore, Dr Gerry Shaper (Mill Hill, London, UK) pointed out, vital information about changes in drinking pattern over time and the effects of heavy drinking in youth are being lost by the practice of lumping together lifelong teetotallers and ex-drinkers as one all purpose category, `non-drinkers'. But the biochemists in the blue corner were far more enthusiastic. Professor Ian Puddey (University of Western Australia, Perth, Australia) reviewed the possible role of the free radicals and antioxidants in alcoholic beverages in protecting against coronary heart disease. His in vitro studies have shown that polyphenolic compounds, such as flavonoids and phenolic acids, can dose-dependently inhibit serum and low-density lipoprotein (LDL) oxidation. Beverages containing high levels of polyphenols, such as red wine and dark beers, have a greater antioxidant effect than white wine and other substances with a low polyphenol content. However, Puddey was careful to point out that these findings are not sufficient to send us reaching for the Bordeaux—for two reasons. First, there have not as yet been any convincing in vivo studies of this phenomenon and, second, the much-vaunted flavonoids and polyphenolics are in fact present in a large number of plant products including tea, fruit, onions, and olive oil. So assuming for a moment that much of the `beneficial' effect of alcohol arises from the antioxidant effect of the polyphenolic compounds therein, why don't we all switch to red grape juice instead and save ourselves from possible cirrhosis, cancers, haemorrhagic strokes, memory loss, addiction, violence and suicide? Well, quite apart from the fact that many people actually enjoy the taste of `a real drink', it is the ethanol, explained Michael Gaziano (Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA) that does a lot of good, regardless of beverage type. Ethanol raises high-density lipoprotein (HDL) levels. HDL has long been known to protect against heart disease; it is involved in transporting cholesterol from artery walls back to the liver and might interfere with platelet aggregation and stimulate fibrinolysis. `It may not be the only mechanism at play' he conceded, `but I do think it is most likely to be the most important mechanism.' But given that alcohol's `protective effect' only really applies to the over fifties and is probably in the region of 1–3 fewer heart attacks per 1000 person years, `what we need now,' said Gaziano, `is more data on free-living humans so that we can learn about the risk: benefit ratio in different populations.' Until then the symposiasts agreed that it would be sheer folly to plug the so-called beneficial effects of drinking alcohol as though it were some amazing new prophylactic. `Not only could positive public health messages increase heavy drinking,' warned Dr Peter Anderson (WHO), `but they would also present a very misleading image of alcohol to developing world societies unaccustomed to drinking.' `We must not just extrapolate from epidemiological data to public health messages,' cautioned chairman Professor Tim Peters (King's College School of Medicine and Dentistry, London, UK). `To move forward from here', he concluded, `we need some viable animal models, more biochemistry, more genetics, and a good, easy-to-measure, non-invasive blood-alcohol marker so that we can find out once and for all how much people really drink!'  相似文献   

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Electrophoretic patterns of malate dehydrogenase (Mdh), alcohol dehydrogenase (Adh), and 6-phosphogluconate dehydrogenase (Pgd) of Zea mays L. × Tripsacum dactyloides L. hybrids and their parents were compared. The components of enzymes specific to T. dactyloides may be used as markers to identify the following T. dactyloides chromosomes in the hybrids: Tr 16 (Mdh 2 and Pdg 1), Tr 7, and/or Tr 13 (Adh 2). The isozymes of Mdh 2 are supposed as a possible biochemical marker to evaluate the introgression of genes, determining an apomictic mode of reproduction from T. dactyloides (localized on Tripsacum 16 chromosome) into Z. mays. The isozymes may be used as markers for the identification of maize chromosomes 1 and 6 in the hybrids as well. Chromosome count taken on the examined hybrids showed the addition of 9 to 13 chromosomes of T. dactyloides to maize chromosome complement.  相似文献   

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Pseudomonas 0–3 strain which was isolated from soil can grow on polyvinyl alcohol (PVA) as a sole carbon source. When 0.5 per cent of PVA (500, 1500 or 2000) was employed as the carbon source in the culture medium, PVA was almost completely lost from the culture fluid after a week and the concentration of total organic carbon measured by a TOC analyzer decreased from the initial value of about 2700 ppm to 250~300 ppm after 7~10 days culture. This bacterium was found to produce and secrete an inducible enzyme which degrade PVA. The way by which this enzyme degrades PVA was examined and the results were obtained which suggested that PVA was broken down oxidatively in a way of endowise splitting. However, the mechanism of PVA degradation has not been clarified yet. The optimum pH and temperature for enzyme activity were examined and they were 7.5~8.5 and 35~45°C, respectively. Morphological and biological characteristics of this bacterium were examined and it was similar to a strain of Pseudomonas boreopolis.  相似文献   

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Xylose-to-xylitol conversion was investigated in a bench-scale bioreactor using Candida guilliermondii cells entrapped within polyvinyl alcohol-hydrogel beads in a system operated in repeated-batch mode with cell recycling. Yeast-viable cells were immobilized in the support using the freezing–thawing method. Bioconversion assays were performed in a stirred tank reactor operated at 400-rpm agitation speed, 30°C temperature, and 1.04-vvm air flow rate. The system was explored during six successive cycles, and a small decrease in the conversion performance in the fifth cycle was observed, but the biocatalytic activity of the microorganism was recovered in the sixth cycle after washing the particles. During the process, the hydrogel beads maintained their shape and size without appreciable deterioration. Xylitol production, yield factor, and volumetric productivity increased with progressive recycling of cells and achieved their maximum values (P F = 39.7 g l−1; Y P/S = 0.77 g g−1; Q P = 0.53 g l−1 h−1, respectively) after the third cell recycling, probably because of cells’ adaptation to the medium.  相似文献   

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Mitochondrial dysfunction is a hallmark of beta-amyloid (Aβ)-induced neuronal toxicity in Alzheimer’s disease (AD). Epidemiological studies have indicated that alcohol consumption plays a role in the development of AD. Here we show that alcohol exposure has a synergistic effect on Aβ-induced neuronal cell death. Aβ-treated cultured neurons displayed spontaneous generation of reactive oxygen species (ROS), disruption of their mitochondrial membrane potential, induction of caspase-3 and p53 activities, and loss of cell viability. Alcohol exposure facilitated Aβ-induced neuronal cell death. Our study shows that alcohol consumption enhances Aβ-induced neuronal cell death by increasing ROS and mitochondrial dysfunction.  相似文献   

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Sixteen Adh-negative mutants (induced by ethyl methanesulfonate) were examined for the presence of inactive alcohol dehydrogenase (ADH) protein. Four techniques were utilized in an effort to detect this protein: hybrid enzyme formation, intra-cistronic complentation, sodium dodecyl sulfate electrophoresis and antibody precipitation. Eleven of the sixteen negative strains showed evidence of inactive ADH protein and are preseumably mutations in the strutural element. These results are discussed in light of some recent models of gene organization in higher organisms.  相似文献   

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Background

Research conducted in high-income countries has investigated influences of socioeconomic inequalities on drinking outcomes such as alcohol use disorders (AUD), however, associations between area-level neighborhood social deprivation (NSD) and individual socioeconomic status with these outcomes have not been explored in Brazil. Thus, we investigated the role of these factors on drink-related outcomes in a Brazilian population, attending to male-female variations.

Methods

A multi-stage area probability sample of adult household residents in the São Paulo Metropolitan Area was assessed using the WHO Composite International Diagnostic Interview (WMH-CIDI) (n = 5,037). Estimation focused on prevalence and correlates of past-year alcohol disturbances [heavy drinking of lower frequency (HDLF), heavy drinking of higher frequency (HDHF), abuse, dependence, and DMS-5 AUD] among regular users (RU); odds ratio (OR) were obtained.

Results

Higher NSD, measured as an area-level variable with individual level variables held constant, showed an excess odds for most alcohol disturbances analyzed. Prevalence estimates for HDLF and HDHF among RU were 9% and 20%, respectively, with excess odds in higher NSD areas; schooling (inverse association) and low income were associated with male HDLF. The only individual-level association with female HDLF involved employment status. Prevalence estimates for abuse, dependence, and DSM-5 AUD among RU were 8%, 4%, and 8%, respectively, with excess odds of: dependence in higher NSD areas for males; abuse and AUD for females. Among RU, AUD was associated with unemployment, and low education with dependence and AUD.

Conclusions

Regular alcohol users with alcohol-related disturbances are more likely to be found where area-level neighborhood characteristics reflect social disadvantage. Although we cannot draw inferences about causal influence, the associations are strong enough to warrant future longitudinal alcohol studies to explore causal mechanisms related to the heterogeneous patterns of association and male-female variations observed herein. Hopefully, these findings may help guide future directions for public health.  相似文献   

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Cigarettes and alcohol are the most abused substances in the world and are commonly co-abused. Nicotine primarily acts in the brain on nicotinic acetylcholine receptors (nAChR), which are also a target for alcohol. The alpha6 subunit of nAChR is expressed almost exclusively in the brain reward system and may modulate the rewarding properties of alcohol and nicotine. Recently, N,N-decane-1,10-diyl-bis-3-picolinium diiodide (bPiDI) was synthesized as a selective, brain penetrant α6 subunit antagonist that reduces nicotine self-administration. The current study aimed to examine the effects of bPiDI on alcohol self-administration in inbred alcohol-preferring (iP) rats. Adult, male iP rats were trained to self-administer alcohol or sucrose. Once stable responding was achieved, rats were injected with bPiDI (1, 3 mg/kg, i.p.) and tested for self-administration under fixed and progressive ratio schedules of reinforcement. They subsequently underwent extinction, in which no rewards or cues were presented in the operant chambers. Then, they were injected with bPiDI prior to testing for cue-induced reinstatement of reward seeking. bPiDI (3 mg/kg) significantly reduced alcohol self-administration in both fixed and progressive ratios without any effects on sucrose self-administration or locomotor activity. In contrast, bPiDI (3 mg/kg) did not inhibit cue-induced reinstatement of either alcohol or sucrose seeking. The results support the involvement of α6 containing nAChR in reinforcing effects of alcohol, but not relapse to alcohol-seeking, without any impact on responding for a natural reward or general activity. bPiDI may be a potential lead molecule for a therapeutic strategy to limit nicotine and alcohol consumption.  相似文献   

20.
Secondary structure of α-chymotrypsin in water/ethanol was investigated by circular dichroic (CD) spectroscopy. The changes in catalytic activity were discussed in terms of structural changes of the enzyme. α-Chymotrypsin formed β-sheet structure in water/ethanol (50/50 by volume), but it was substantially less active as compared to that in water. At water/ethanol 10/90, α-chymotrypsin took on a native-like structure, which gradually changed to β conformation with concomitant loss of activity. Change of solvent composition from water/ethanol 50/50 to 90/10 or 10/90 by dilution with water or ethanol, respectively, led to partial recovery of native or native-like structure and activity. In water/methanol, α-chymotrypsin tended to form stable β-sheet structure at water/methanol ratios lower than 50/50, but the catalytic activity decreased with time. Change to α-helix structure with substantial loss in catalytic activity was observed when α-chymotrypsin was dissolved in water/2,2,2-trifluoroethanol with water contents lower than 50%. In water/2,2,2-trifluoroethanol 90/10, α-chymotrypsin initially had the CD spectrum of native structure, but it changed with time to that characteristic of β-sheet structure.  相似文献   

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