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1.
Human skin was fixed in Davidson's solution (95% alcohol, 35; formalin, 20; glacial acetic acid, 10; and distilled water, 35—parts by volume) and sections prepared through paraffin embedding in the usual manner. Stock stains were: I(BS)—Biebrich scarlet, 1 gm in 100 ml of 50% alcohol to which 0.3 gm of phosphotungstic acid and 5 ml of glacial acetic acid were added—and II(FG)—fast green, 0.5 gm in 85 ml of 50% alcohol to which 0.3 gm of phosphotungstic acid, 0.3 gm of phosphomolybdic acid, and 15 ml of glacial acetic acid were added. Experimental staining solutions were prepared in the following proportions of stock BS to stock FG—1:1, 2:1, 3:1, 1:2 and 1:3. Sections were brought to 50% alcohol and stained for 15, 20, 25 and 30 min in each of the five BS-FG mixtures, rinsed in 50% alcohol, then dehydrated in 70%, 95%, and absolute alcohol, 2 min each; cleared in xylene, and covered in balsam. The 2:1 (optimum proportion) combination of BS with FG, acting for 20 min, yielded 97% sex chromatin-positive nuclei in female material. If sections were stained in stock solution BS for 2 min, they could be differentiated by a 20 min treatment in the mordanting component of stock FG (without dye) to give a one-color stain. Such stains gave about the same percentage of sex chromatin-positive nuclei as those obtained by the regular two-color procedure. These modifications are simpler, more rapid, and yield results comparable to previously employed techniques.  相似文献   

2.
Indirect determination of partition coefficients of volatile substances in the system oleyl alcohol—water for analysis of quantitative structure—activity relationships is discussed. Water and oleyl alcohol were used as stationary liquid phases in gas—liquid chromatography. In order to correct the results for adsorption effects, two new procedures using a standard substance were suggested. The procedures were compared with a procedure used by Conder et al. Comparison of molar hydration enthalpies and entropies derived from experimental results of a series of aliphatic alcohols with calorimetric data proved that all procedures under consideration yielded true partition coefficients.  相似文献   

3.
Results of research into ethanol metabolism in yeast organisms with highly pronounced aerobic metabolism are reviewed. The low activity of NAD-dependent alcohol dehydrogenase (EC 1.1.1.1), observed under conditions of aerobic yeast growth on ethanol, demonstrates that alternative enzyme systems—alcohol oxidase (EC 1.1.3.13), microsomal ethanol-oxidizing system (including cytochrome P-450), and catalase (EC 1.11.1.6)—may be involved in the alcohol oxidation. The role of these systems in alcohol oxidation and the conditions favoring their operation in this processes are analyzed. It is concluded that iron ions are important regulators of ethanol metabolism for the microorganisms of this group.  相似文献   

4.
To study effect of sulphacetamide and sulphathiazole on the interaction of aliphatic alcohols with bovine serum albumin (BSA) in aqueous solution, 1H n.m.r. spectra of alcohols (A) and sulphonamides (S) were monitored in D2O, in the binary systems (A—S), (A—BSA), (S—BSA) and in the ternary system (A—BSA—S) at pH 7.0. The n.m.r. lines of alcohols, markedly and selectively broadened in the systems (A—BSA), were gradually narrowed on addition of increasing concentrations of sulphonamides. The narrowing was dependent on the chain length and branching of the alcohol molecules with residual broadening significantly greater for the α-methylenes or methines next to ?OH. The results suggest the release of alcohol molecules weakly associated to BSA after the formation of the specific sulphonamide—BSA complex. They also reflect selectively strong immobilization of the fragments next to ?OH in the A—BSA complexes, probably by hydrogen bonds between hydroxyls and the peptide groups of protein.  相似文献   

5.
In addition to furnishing clothing, food and shelter—the basic necessities of life—plants, in their utilization by man, have also furnished problems of public health in their production of alcohol, narcotics, allergies, poisons and specific human diseases.  相似文献   

6.
Purification and comparative studies of alcohol dehydrogenases   总被引:2,自引:0,他引:2  
Alcohol dehydrogenases from various animal and plant sources were purified by a common procedure which employed DEAE, Sephadex-G100 and affinity chromatographies. The procedure achieves an 80-130 fold purification for animal enzymes. However, only a 5-15 fold purification for plant enzymes was attained because of the instability of these enzymes. Purified alcohol dehydrogenases from animal and plant sources differ in coenzyme and substrate specificities. The enzymes from mammalian, avian and fish livers display aldehyde oxidizing and esterolytic activities in addition to alcohol oxidizing activity. However, the enzymes from plants and yeast show only the oxidative activity toward alcohols. Chemical modifications have been performed to identify amino acid residues which are essential to the oxidative and esterolytic activities of alcohol dehydrogenases.  相似文献   

7.
Applied Microbiology and Biotechnology - Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound enzymes—alcohol dehydrogenase and aldehyde...  相似文献   

8.
Hepatocellular carcinoma (HCC) is a major cause of cancer-related deaths worldwide. More than 90% of primary HCC is HCC. Hepatitis C virus (HCV) infection and alcohol consumption have been widely accepted as two major risk factors for developing HCC. Herein, we aimed to identify DNA methylation genes related to both HCV infection and alcohol consumption. In this study, we identified methylation genes that were associated with the risk of HCV infection and alcohol consumption, respectively, by a large-scale bioinformatic analysis. Through PPI network analysis, we revealed the associations between the two types of genes and found six hub genes—TAF1, SAT1, Phospholipase C-beta 2, FGD1, ARHGAP4, and ARHGEF9—that may be associated with both HCV infection and alcohol consumption. Gene Ontology enrichment analysis was used to analyze the function which these genes in the network enriched. Among them, TAF1, SAT1, and ARHGEF9 were methylated genes that have been found to be related to tumor progression in HCC patients. Through independent data sets, we verified the methylation pattern of these six genes in HCC samples that had both HCV infection and alcohol consumption risks. Furthermore, we found that three of the six methylated genes were also associated with the prognosis of HCC patients. To summarize, we identified six hub genes that were associated with both HCV infection and alcohol consumption in the progress of HCC. The six methylation genes that might play an important role in both HCV infection and alcohol consumption would be potential therapy targets for HCC.  相似文献   

9.
A rapid gel filtration chromatography method is described for determination of the molecular weight distribution (MWD) of peptide mixtures by using calibrated Sephadex microbore columns. The method was applied to MWD analysis of peptide mixtures resulting from trypsin and pepsin digestion of glycinin—the major soybean storage protein—under different incubation conditions of pH, temperature, and time of hydrolysis. Possible sources of errors and suggestions for improvement are discussed.  相似文献   

10.
The mass media is a major source of health information for the public, and as such the quality and independence of health news reporting is an important concern. Concerns have been expressed that journalists reporting on health are increasingly dependent on their sources—including representatives of industries responsible for manufacturing health-related products—for story ideas and content. Many critics perceive an imbalance of power between journalists and industry sources, with industry being in a position of relative power, however the empirical evidence to support this view is limited. The analysis presented here—which is part of a larger study of industry-journalist relationships—draws on in-depth, semi-structured interviews with representatives of health-related industries in Australia to inductively examine their perceptions of power relations between industry and journalists. Participants painted a picture in which journalists, rather than themselves, were in a position to control the nature, extent, and outcome of their interactions with industry sources. Our results resonate with the concept of “mediatisation” as it has been applied in the domain of political reporting. It appears that, from the perspective of industry representatives, the imposition of media logic on health-related industries may inappropriately influence the information that the public receives about health-related products.  相似文献   

11.
The present article investigates to what extent and level of success urban mining—the recovery of resources from anthropogenic stock—has been applied in the past during shortages of primary resources. As a case study, the Austrian economy during World War I—when raw materials indeed had to be substituted from secondary sources—is analyzed here. By means of material flow analysis, the management of copper, an important and relatively scarce metal that is difficult to substitute, is examined. The combination of increased demand for copper (for ammunition) and constraints on supply from sources other than the domestic anthroposphere highlights the importance of planning for and surveying urban mining activities. The results also indicate limitations to extracting a large share of copper from the anthroposphere, even in the face of a critical shortage. Although extreme measures, such as confiscation, were taken, only 1.7 kilograms of copper per capita (kg Cu/cap), amounting to perhaps as little as 10% of the anthropogenic stock, could be made available through the end of the war.  相似文献   

12.
Abstract

On the functional activation of germinanting seeds. Note V. Alcohol dehydrogenase activity. — The activity of alcohol dehydrogenase is determined by spettrophotometric method on acetone precipitates of dry and germinating seeds of leguminous and graminaceous plants.

The activity of alcohol dehydrogenase is present, even with remarkable different values, in all seeds and in their various parts, singularly examined.

During germination in aerobic conditions, after a first, not strong, increase, the alcohol dehydrogenase activity sensibly decreases.  相似文献   

13.
Abstract

Changes of specific level of four regulatory enzymes (citrate cleavage enzyme, pyruvate kinase, isocitrate lyase and alcohol dehydrogenase) — as a response to diverse environmental conditions (carbon source, Zn availability) — take place in the yeast Rhodotorula gracilis according to a specific control pattern and can be interpreted in terms of induction-repression mechanisms mediated by specific metabolic signals.  相似文献   

14.
During adolescence, interactions with peers influence a teen’s attitudes and behaviors. Adolescents seek for peer approval and acceptance, which may bring them to engage in health-risky behaviors such as smoking and drinking. In this study, we estimate the impact of peers on the drug use of Spanish students aged 14 to 18. We focus on the consumption of alcohol and tobacco, the most prevalent substances used at those ages. We estimate the effect of the average classmates’ consumption—the measure of peers’ use—on individual consumption. Since peers’ use affects individual use and vice versa, we correct for this bias using instrumental variables. Results show that peers’ consumption increases substantially the probability of using alcohol, while it does not significantly affect tobacco consumption. Our results are not sensitive to using different time spans of consumption. This study shows also novel evidence indicating that the higher the proportion of grade-retained students in the class, the stronger the peer effects, especially for alcohol. This suggests that future reforms of the grade retention policy should also consider the negative effects on non-academic outcomes, such as substance use.  相似文献   

15.
Only four kinds of native nut—hazelnut, chinquapin and two acorns—and introduced American walnut, Persian walnut and European filbert constitute the sources of edible nuts in this region.  相似文献   

16.
Interest in alternative fuel sources has grown in recent years in response to a confluence of factors, including concerns over our reliance on and increasing demand for fossil fuels as well as the deleterious environmental effects of fossil fuel extraction and utilization. The use of microbe-derived fuel alcohols is a viable alternative, as they are renewable, emit fewer greenhouse gasses, and require little augmentation of current energy infrastructure as compared to other sustainable transportation options such as electric vehicles and fuel cells. Here, we present a brief overview of candidate substrates for alcohol production with a focus on lignocellulosic sources, relevant microorganisms under research for industrialization and the biotechnological techniques used to improve alcohol production phenotypes.  相似文献   

17.
In the present study, the metabolic pathways involved in the degradation of benzyl alcohol and 1-butanol, the hydrolyzed products of butyl benzyl phthalate, were investigated by the Gordonia sp. strain MTCC 4818. The strain can utilize both benzyl alcohol and 1-butanol individually as sole carbon sources, where benzyl alcohol was found to be metabolized via benzaldehyde, benzoic acid and catechol, which was further degraded by ortho-cleavage dioxygenase to cis,cis-muconic acid and subsequently to muconolactone leading to tricarboxylic acid cycle. On the other hand, 1-butanol was metabolized via butyraldehyde and butyric acid, which was channeled into the tricarboxylic acid cycle via the beta-oxidation pathway. Numbers of dehydrogenases, both NAD+-dependent and NAD+-independent, were found to be involved in the degradation of benzyl alcohol and 1-butanol, where several dehydrogenases exhibited relaxed substrate specificity. Both 2,3- and 3,4-dihydroxybenzoic acids were utilized by the test organism for growth and metabolized by the ortho-cleavage pathway by the cell-free extract of benzoate-grown cells, similar to catechol, suggesting possible broad substrate specificity of the ring cleavage dioxygenase. Moreover, the test organism can utilize various primary and secondary alcohols, aliphatic aldehydes and acids in the C2-C5 range besides n-hexadecane, 1,4-butanediol and cyclohexanol individually as the sole carbon sources indicating metabolic diversity in the Gordonia sp. strain MTCC 4818.  相似文献   

18.
Alcohol oxidases (Alcohol: O2 Oxidoreductase; EC 1.1.3.x) are flavoenzymes that catalyze the oxidation of alcohols to the corresponding carbonyl compounds with a concomitant release of hydrogen peroxide. Based on substrate specificity, alcohol oxidases may be categorized broadly into four different groups namely, (a) short chain alcohol oxidase (SCAO), (b) long chain alcohol oxidase (LCAO), (c) aromatic alcohol oxidase (AAO), and (d) secondary alcohol oxidase (SAO). The sources reported for these enzymes are mostly limited to bacteria, yeast, fungi, plant, insect, and mollusks. However, the quantum of reports for each category of enzymes considerably varies across these sources. The enzymes belonging to SCAO and LCAO are intracellular in nature, whereas AAO and SAO are mostly secreted to the medium. SCAO and LCAO are invariably reported as multimeric proteins with very high holoenzyme molecular masses, but the molecular characteristics of these enzymes are yet to be clearly elucidated. One of the striking features of the alcohol oxidases that make them distinct from the widely known alcohol dehydrogenase is the avidly bound cofactor to the redox center of these enzymes that obviate the need to supplement cofactor during the catalytic reaction. These flavin-based redox enzymes have gained enormous importance in the development of various industrial processes and products primarily for developing biosensors and production of various industrially useful carbonyl compounds. The present review provides an overview on alcohol oxidases from different categories focusing research on these oxidases during the last decade along with their potential industrial applications.  相似文献   

19.
《Hormones and behavior》2011,59(5):835-843
Prenatal alcohol exposure (PAE) alters adult neurogenesis and the neurogenic response to stress in male rats. As the effects of stress on neurogenesis are sexually dimorphic, the present study investigated the effects of PAE on adult hippocampal neurogenesis under both nonstressed and stressed conditions in female rats. Pregnant females were assigned to one of three prenatal treatments: (1) alcohol (PAE)—liquid alcohol (ethanol) diet ad libitum (36% ethanol-derived calories); (2) pair-fed—isocaloric liquid diet, with maltose–dextrin substituted for ethanol, in the amount consumed by a PAE partner (g/kg body wt/day of gestation); and (3) control—lab chow ad libitum. Female offspring were assigned to either nonstressed (undisturbed) or stressed (repeated restraint stress for 9 days) conditions. On day 10, all rats were injected with bromodeoxyuridine (BrdU) and perfused either 24 hours (cell proliferation) or 3 weeks (cell survival) later. We found that PAE did not significantly alter cell proliferation or survival, whereas females from the pair-fed condition exhibited elevated levels of cell survival compared to control females. Importantly, however, the proportion of both new neurons and new glial cells in the hippocampal dentate gyrus was reduced in PAE compared to control females. Exposure to stress did not alter neurogenesis in any of the prenatal treatment groups. In summary, compared to females from the control condition, prenatal dietary restriction enhanced the survival of new neurons, whereas PAE altered the differentiation of newly produced cells in the adult dentate gyrus. Alterations in hippocampal neurogenesis following PAE may contribute to learning and memory deficits seen in individuals with fetal alcohol spectrum disorders.  相似文献   

20.
An attempt is made to show that the phenomenon of chirality—of which optical activity is but one consequence—is by no means restricted to life on Earth, but is common throughout the universe. Several independent sources have been investigated including: statistical fluctuations; stereoselective physical factors; and energetic differences between enantiomeric molecules. It is emphasised that a search for chirality as an indicator for life elsewhere in space provides an excellent tool for the fascinating question of exobiology. Still one must be aware of the limitations of the experimental methods and their interpretations.  相似文献   

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