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Excessive Drinking (excessive + drinking)
Selected AbstractsThe effectiveness of brief alcohol interventions in primary care settings: A systematic reviewDRUG AND ALCOHOL REVIEW, Issue 3 2009EILEEN F. S. KANER Abstract Issues. Numerous studies have reported that brief interventions delivered in primary care are effective in reducing excessive drinking. However, much of this work has been criticised for being clinically unrepresentative. This review aimed to assess the effectiveness of brief interventions in primary care and determine if outcomes differ between efficacy and effectiveness trials. Approach. A pre-specified search strategy was used to search all relevant electronic databases up to 2006. We also hand-searched the reference lists of key articles and reviews. We included randomised controlled trials (RCT) involving patients in primary care who were not seeking alcohol treatment and who received brief intervention. Two authors independently abstracted data and assessed trial quality. Random effects meta-analyses, subgroup and sensitivity analyses and meta-regression were conducted. Key Findings. The primary meta-analysis included 22 RCT and evaluated outcomes in over 5800 patients. At 1 year follow up, patients receiving brief intervention had a significant reduction in alcohol consumption compared with controls [mean difference: ,38 g week,1, 95%CI (confidence interval): ,54 to ,23], although there was substantial heterogeneity between trials (I2 = 57%). Subgroup analysis confirmed the benefit of brief intervention in men but not in women. Extended intervention was associated with a non-significantly increased reduction in alcohol consumption compared with brief intervention. There was no significant difference in effect sizes for efficacy and effectiveness trials. Conclusions. Brief interventions can reduce alcohol consumption in men, with benefit at a year after intervention, but they are unproven in women for whom there is insufficient research data. Longer counselling has little additional effect over brief intervention. The lack of differences in outcomes between efficacy and effectiveness trials suggests that the current literature is relevant to routine primary care. [Kaner EFS, Dickinson HO, Beyer F, Pienaar E, Schlesinger C, Campbell F, Saunders JB, Burnand B, Heather N. The effectiveness of brief alcohol interventions in primary care settings: A systematic review. Drug Alcohol Rev 2009;28:301,323] [source] Pre-operative screening for excessive alcohol consumption among patients scheduled for elective surgeryDRUG AND ALCOHOL REVIEW, Issue 2 2007SWATI SHOURIE Abstract Pre-operative intervention for excessive alcohol consumption among patients scheduled for elective surgery has been shown to reduce complications of surgery. However, successful intervention depends upon an effective and practical screening procedure. This study examines current screening practices for excessive alcohol consumption amongst patients scheduled for elective surgery in general hospitals. It also examines the appropriateness of potential sites and staff for pre-operative screening. Forms used routinely to assess alcohol consumption in the pre-admission clinics (PAC) of eight Sydney hospitals were examined. In addition, the appropriateness of six staff categories (surgeons, surgeons' secretaries, junior medical officer, anaesthetists, nurses and a research assistant) and of two sites (surgeons' office and PAC) in conducting additional screening was assessed at two hospitals. Outcomes included observed advantages and disadvantages of sites and personnel, and number of cases with excessive drinking identified. There was duplication in information collected routinely on alcohol use in the PACs in eight Sydney Hospitals. Questions on alcohol consumption in patient self-completion forms were not validated. The PAC provided for efficient screening but time to surgery was typically too short for successful intervention in many cases. A validated tool and efficient screening procedure is required to detect excessive drinking before elective surgery. Patients often present to the PAC too close to the time of surgery for any change in drinking to reverse alcohol's effects. The role of the referring general practitioner and of printed advice from the surgeon in preparing patients for surgery needs further investigation. [source] Community alcohol outlet density and underage drinkingADDICTION, Issue 2 2010Meng-Jinn Chen ABSTRACT Aim This study examined how community alcohol outlet density may be associated with drinking among youths. Methods Longitudinal data were collected from 1091 adolescents (aged 14,16 at baseline) recruited from 50 zip codes in California with varying levels of alcohol outlet density and median household income. Hierarchical linear models were used to examine the associations between zip code alcohol outlet density and frequency rates of general alcohol use and excessive drinking, taking into account zip code median household income and individual-level variables (age, gender, race/ethnicity, personal income, mobility and perceived drinking by parents and peers). Findings When all other factors were controlled, higher initial levels of drinking and excessive drinking were observed among youths residing in zip codes with higher alcohol outlet densities. Growth in drinking and excessive drinking was, on average, more rapid in zip codes with lower alcohol outlet densities. The relation of zip code alcohol outlet density with drinking appeared to be mitigated by having friends with access to a car. Conclusion Alcohol outlet density may play a significant role in initiation of underage drinking during early teenage, especially when youths have limited mobility. Youth who reside in areas with low alcohol outlet density may overcome geographic constraints through social networks that increase their mobility and the ability to seek alcohol and drinking opportunities beyond the local community. [source] Older adults' alcohol consumption and late-life drinking problems: a 20-year perspectiveADDICTION, Issue 8 2009Rudolf H. Moos ABSTRACT Aims The aim of this study was to identify changes in patterns of alcohol consumption over a 20-year interval among older women and men, and to examine the associations between guideline-defined excessive drinking and late-life drinking problems. Design, participants and measures A community sample of 719 adults between 55 and 65 years of age who consumed alcohol at or prior to baseline participated in a survey of alcohol consumption and drinking problems and was followed 10 years and 20 years later. Findings The likelihood of excessive drinking declined over the 20-year interval as adults matured into their 70s and 80s. However, at ages 75,85, 27.1% of women and 48.6% of men consumed more than two drinks per day or seven drinks per week. At comparable guideline levels of alcohol consumption, older men were more likely to have drinking problems than were older women. Consumption of more than two drinks per day or seven drinks per week was identified as a potential conservative guideline for identifying excessive drinking associated with an elevated likelihood of drinking problems. Conclusions A substantial percentage of older adults who consume alcohol engage in guideline-defined excessive drinking and incur drinking problems. The finding that older men may be more likely than older women to experience problems when they drink beyond guideline levels suggests that alcohol guidelines for men should not be set higher than those for women. [source] Family members of relatives with alcohol, drug and gambling problems: a set of standardized questionnaires for assessing stress, coping and strainADDICTION, Issue 11 2005Jim Orford ABSTRACT Aims To describe a set of standard questionnaire measures for the assessment of the needs of family members of relatives with alcohol, drug or gambling problems, and to present evidence of their reliability and validity from a series of related studies. Design Includes cross-sectional and repeated-measurement studies. Setting and participants Family members affected by and concerned about the problem drinking or drug-taking of close relatives in treatment and non-treatment samples in the United Kingdom (white and Sikh) and Mexico City; family members of untreated heavy drinkers; and family members of problem gamblers. Measurements Four measures derived from a stress,strain,coping,support model of alcohol, drugs and gambling problems and the family: Family Member Impact scale (FMI), Symptom Rating Test (SRT), Coping Questionnaire (CQ), and Hopefulness,Hopelessness scale (HOPE). FMI, SRT and CQ assess stress, strain and coping, respectively. The exact role of HOPE in the model remains to be determined. The support component remains unmeasured. Findings Results from a number of studies support the internal reliability, discriminant and construct validity and sensitivity to change of the SRT and its two constituent scales (psychological and physical symptoms) and at least two subscales of the CQ (engaged and tolerant,inactive coping). Although showing evidence of satisfactory reliability and some evidence of discriminant validity, further work may be required on the CQ withdrawal coping subscale. Evidence suggests that the FMI is reliable and valid and may have a factor structure that will support future research (distinguishing worrying behaviour from active disturbance). HOPE is a new measure showing promising characteristics. Conclusions A set of standard measures is available for helping to assess the needs of concerned and affected family members, derived from an explicit model of the family in relation to excessive drinking, drug taking or gambling. It may have a role to play in correcting the current neglect of the needs of such family members, estimated to be in the region of nearly a million adults in Britain alone. [source] Addiction as excessive appetiteADDICTION, Issue 1 2001Jim Orford The excessive appetite model of addiction is summarized. The paper begins by considering the forms of excessive appetite which a comprehensive model should account for: principally, excessive drinking, smoking, gambling, eating, sex and a diverse range of drugs including at least heroin, cocaine and cannabis. The model rests, therefore, upon a broader concept of what constitutes addiction than the traditional, more restricted, and arguably misleading definition. The core elements of the model include: very skewed consumption distribution curves; restraint, control or deterrence; positive incentive learning mechanisms which highlight varied forms of rapid emotional change as rewards, and wide cue conditioning; complex memory schemata; secondary, acquired emotional regulation cycles, of which 'chasing', 'the abstinence violation effect' and neuroadaptation are examples; and the consequences of conflict. These primary and secondary processes, occurring within diverse sociocultural contexts, are sufficient to account for the development of a strong attachment to an appetitive activity, such that self-control is diminished, and behaviour may appear to be disease-like. Giving up excess is a natural consequence of conflict arising from strong and troublesome appetite. There is much supportive evidence that change occurs outside expert treatment, and that when it occurs within treatment the change processes are more basic and universal than those espoused by fashionable expert theories. [source] REVIEW: The alcohol-preferring P rat and animal models of excessive alcohol drinkingADDICTION BIOLOGY, Issue 3-4 2006Richard L. Bell ABSTRACT The alcohol-preferring, P, rat was developed by selective breeding to study ethanol drinking behavior and its consequences. Characterization of this line indicates the P rat meets all of the criteria put forth for a valid animal model of alcoholism, and displays, relative to their alcohol-non-preferring, NP, counterparts, a number of phenotypic traits associated with alcohol abuse and alcoholism. Behaviorally, compared with NP rats, P rats are less sensitive to the sedative and aversive effects of ethanol and more sensitive to the stimulatory effects of ethanol. Neurochemically, research with the P line indicates the endogenous dopaminergic, serotonergic, GABAergic, opiodergic, and peptidergic systems may be involved in a predisposition for alcohol abuse and alcoholism. Paralleling the clinical literature, genetically selected P rats display levels of ethanol intake during adolescence comparable to that seen during adulthood. Binge drinking has been associated with an increased risk for health and other problems associated with ethanol abuse. A model of binge-like drinking during the dark cycle indicates that P rats will consume 6 g/kg/day of ethanol in as little as three 1-hour access periods/day, which approximates the 24-hour intake of P rats with free-choice access to a single concentration of ethanol. The alcohol deprivation effect (ADE) is a transient increase in ethanol intake above baseline values upon re-exposure to ethanol access after an extended period of deprivation. The ADE has been proposed to be an animal model of relapse behavior, with the adult P rat displaying a robust ADE after prolonged abstinence. Overall, these findings indicate that the P rat can be effectively used in models assessing alcohol-preference, a genetic predisposition for alcohol abuse and/or alcoholism, and excessive drinking using protocols of binge-like or relapse-like drinking. [source] Alcohol self-administration acutely stimulates the hypothalamic-pituitary-adrenal axis, but alcohol dependence leads to a dampened neuroendocrine stateEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2008Heather N. Richardson Abstract Clinical studies link disruption of the neuroendocrine stress system with alcoholism, but remaining unknown is whether functional differences in the hypothalamic-pituitary-adrenal (HPA) axis precede alcohol abuse and dependence or result from chronic exposure to this drug. Using an operant self-administration animal model of alcohol dependence and serial blood sampling, we show that long-term exposure to alcohol causes significant impairment of HPA function in adult male Wistar rats. Acute alcohol (voluntary self-administration or experimenter-administered) stimulated the release of corticosterone and its upstream regulator, adrenocorticotropic hormone, but chronic exposure sufficient to produce dependence led to a dampened neuroendocrine state. HPA responses to alcohol were most robust in ,low-responding' non-dependent animals (averaging < 0.2 mg/kg/session), intermediate in non-dependent animals (averaging ,0.4 mg/kg/session), and most blunted in dependent animals (averaging ,1.0 mg/kg/session) following several weeks of daily 30-min self-administration sessions, suggesting that neuroendocrine tolerance can be initiated prior to dependence and relates to the amount of alcohol consumed. Decreased expression of corticotropin-releasing factor (CRF) mRNA expression in the paraventricular nucleus of the hypothalamus and reduced sensitivity of the pituitary to CRF may contribute to, but do not completely explain, neuroendocrine tolerance. The present results, combined with previous studies, suggest that multiple adaptations to stress regulatory systems may be brought about by excessive drinking, including a compromised hormonal response and a sensitized brain stress response that together contribute to dependence. [source] Binge Drinking and Suboptimal Self-Rated Health Among Adult DrinkersALCOHOLISM, Issue 8 2010James Tsai Background:, Binge drinking accounts for more than half of the 79,000 annual deaths in the United States that are owing to excessive drinking. The overall objective of our study was to examine the prevalence of binge drinking and consumption levels associated with suboptimal self-rated health among the general population of adult drinkers in all 50 states and territories in the United States. Methods:, The study included a total of 200,587 current drinkers who participated in the 2008 Behavioral Risk Factor Surveillance System (BRFSS) survey. We estimated the prevalence of binge drinking (i.e., ,5 drinks on 1 occasion for men or ,4 drinks on 1 occasion for women) and heavy drinking (i.e., an average of >14 drinks per week for men or >7 drinks per week for women), as well as the average number of binge episodes per person during a 30-day period. Odds ratios were produced with multivariate logistic regression models using binge-drinking levels as a predictor; status of suboptimal self-rated health was used as an outcome variable while controlling for sociodemographic, health, and behavioral risk factors. Results:, We estimate that 34.7 million adult drinkers in the United States engaged in binge drinking in 2008, including an estimated 42.2% who reported either heavy drinking or at least 4 binge-drinking episodes in a 30-day period. Binge drinking with such levels was associated with a 13,23% increased likelihood of reporting suboptimal self-rated health, when compared to the nonbinge drinkers. Conclusions:, Binge drinking continues to be a serious public health concern. Frequent binge drinkers or binge drinkers who consume alcohol heavily are especially at risk of suboptimal self-rated health. Our findings underscore the importance of broad-based implementation in health care settings of screening for and brief interventions to address alcohol misuse, as well as the continuing need to implement effective population-based prevention strategies to reduce alcohol-related morbidity and mortality. [source] Intensity and Duration of Chronic Ethanol Exposure Is Critical for Subsequent Escalation of Voluntary Ethanol Drinking in MiceALCOHOLISM, Issue 11 2009William C. Griffin III Background:, Excessive alcohol drinking continues to be an important health problem. Recent studies from our laboratory and others have demonstrated that animal models of ethanol dependence and relapse can contribute to understanding factors that contribute to excessive drinking. In this study, we tested the hypothesis that the amount and duration of ethanol exposure is critical for promoting the escalation in drinking by mice given access to ethanol in a limited access paradigm. Methods:, We used several methods of chronic intermittent ethanol exposure in male C57BL/6J mice that would vary in the amount and duration of exposure to ethanol as indicated by blood ethanol concentrations (BEC). After establishing baseline drinking in the mice using a 2 hours, 2 bottle choice drinking paradigm, each study involved alternating between periods of ethanol exposure and periods of limited access to ethanol (1 cycle) for a total of 3 cycles. In Study 1, mice were allowed extended access (16 hours) to ethanol for oral consumption or remained in the home cage. In Study 2, the ethanol exposure consisted of intragastric gavage of increasing doses of ethanol or isocaloric sucrose as the control. Study 3 compared intragastric gavage combined with pyrazole, an alcohol dehydrogenase inhibitor, with vapor inhalation of ethanol using procedures known to lead to increased drinking in mice. Finally, Study 4 was a retrospective review of several studies conducted in our laboratory using inhalation procedures. The retrospective review encompassed a range of postvapor chamber BEC values and ethanol intakes that would allow a relationship between increased drinking and BEC to be examined. Results:, Allowing mice to drink for longer periods of time did not cause increased drinking in subsequent limited access sessions. Likewise, gastric intubation of ethanol which produced high BEC (>300 mg/dl) with or without pyrazole did not increase drinking. Only the vapor inhalation procedure, which was associated with sustained BEC above 175 mg/dl for the entire exposure period resulted in increased drinking. The retrospective study provided further evidence that sustained BEC levels above 175 mg/dl was critical to the escalation in drinking. Conclusions:, We found that the intensity (amount) and duration of ethanol exposure, indexed by BEC, is critical to produce increased drinking in mice. Specifically, BEC must regularly exceed 175 mg/dl for the escalation in drinking to occur. Future studies will examine neurobiological adaptations that may underlie the increased drinking behavior caused by chronic intermittent ethanol exposure. [source] Suppression of Heavy Drinking and Alcohol Seeking by a Selective ALDH-2 InhibitorALCOHOLISM, Issue 11 2009Maria P. Arolfo Background:, Inherited human aldehyde dehydrogenase 2 (ALDH-2) deficiency reduces the risk for alcoholism. Kudzu plants and extracts have been used for 1,000 years in traditional Chinese medicine to treat alcoholism. Kudzu contains daidzin, which inhibits ALDH-2 and suppresses heavy drinking in rodents. Decreased drinking due to ALDH-2 inhibition is attributed to aversive properties of acetaldehyde accumulated during alcohol consumption. However, daidzin can reduce drinking in some rodents without necessarily increasing acetaldehyde. Therefore, a selective ALDH-2 inhibitor might affect other metabolic factors involved in regulating drinking. Methods:, Aldehyde dehydrogenase 2 inhibitors were synthesized based on the co-crystal structure of ALDH-2 and daidzin. We tested the efficacy of a highly selective reversible ALDH-2 inhibitor, CVT-10216, in models of moderate and high alcohol drinking rats. We studied 2-bottle choice and deprivation-induced drinking paradigms in Fawn Hooded (FH) rats, operant self-administration in Long Evans (LE), FH, and inbred P (iP) rats and in cue-induced reinstatement in iP rats. We also assayed blood acetaldehyde levels as well as dopamine (DA) release in the nucleus accumbens (NAc) and tested possible rewarding/aversive effects of the inhibitor in a conditioned place preference (CPP) paradigm. Results:, CVT-10216 increases acetaldehyde after alcohol gavage and inhibits 2-bottle choice alcohol intake in heavy drinking rodents, including deprivation-induced drinking. Moreover, CVT-10216 also prevents operant self-administration and eliminates cue-induced reinstatement of alcohol seeking even when alcohol is not available (i.e., no acetaldehyde). Alcohol stimulates DA release in the NAc, which is thought to contribute to increased drinking and relapse in alcoholism. CVT-10216 prevents alcohol-induced increases in NAc DA without changing basal levels. CVT-10216 does not show rewarding or aversive properties in the CPP paradigm at therapeutic doses. Conclusion:, Our findings suggest that selective reversible ALDH-2 inhibitors may have therapeutic potential to reduce excessive drinking and to suppress relapse in abstinent alcoholics. [source] Changes in the self-regulation guidelines of the US Beer Code reduce the number of content violations reported in TV advertisementsJOURNAL OF PUBLIC AFFAIRS, Issue 1-2 2010Thomas F. Babor From a public health perspective, alcohol advertising should not be directed at vulnerable groups, nor should it portray excessive drinking or other objectionable content such as illegal activity. To promote the responsible advertising of alcoholic beverages, alcohol industry groups have developed self-regulation guidelines that describe which types of content (and exposure markets) are unacceptable. In 2006 the US Beer Institute revised the content guidelines of the 1997 Beer Code. This study was designed to determine whether these changes made the revised Code more or less likely for expert judges to report guideline violations, and for alcohol advertisements to include otherwise inappropriate content from a public health perspective. Six alcohol advertisements known or suspected to have multiple content violations were rated by 139 experts selected on the basis of their expertise in public health, mental health, alcohol research and marketing. The ads were rated on two occasions with feedback about other viewers' ratings provided at the second rating. The data were collected by means of a computer-based rating program that used multiple items to evaluate the eight major content guidelines of the US Beer Code. The ratings were scored according to both the 1997 and the 2006 versions of the Beer Code. According to the 1997 criteria, raters identified an average of 26 guideline violations across the six ads; the number of violations was reduced to 18 when the 2006 criteria were applied. The difference was statistically significant and was primarily attributable to changes in guidelines dealing with the portrayal of illegal activity, humorous situations and the act of drinking. By removing or revising commonly violated guidelines, the 2006 Beer Code revision permits portrayal of previously objectionable ad content and increases the likelihood that risky drinking behaviours will be portrayed in US beer advertisements. Copyright © 2009 John Wiley & Sons, Ltd. [source] A STRUCTURAL EQUATION MODELING OF ALCOHOL USE AMONG YOUNG ADULTS IN THE U.S. MILITARY: COMPLEXITIES AMONG STRESS, DRINKING MOTIVES, IMPULSIVITIY, ALCOHOL USE AND JOB PERFORMANCEALCOHOLISM, Issue 2008Sunju Sohn Aims:, Young male adults in the U. S. military drink at much higher rates than civilians and females of the same age. Drinking has been shown to be associated with stress and individuals' ability to effectively cope with stressors. Despite numerous studies conducted on young adults' drinking behaviors such as college drinking, current literature is limited in fully understanding alcohol use patterns of the young military population. The aim of the present study was to develop and test the hypothesized Structural Equation Model (SEM) of alcohol use to determine if stress coping styles moderate the relationship between stress, drinking motives, impulsivity, alcohol consumption and job performance. Methods:, Structural equation models for multiple group comparisons were estimated based on a sample of 1,715 young (aged 18 to 25) male military personnel using the 2005 Department of Defense Survey of Health Related Behaviors among Military Personnel. Coping style was used as the grouping factor in the multi-group analysis and this variable was developed through numerous steps to reflect positive and negative behaviors of coping. The equivalences of the structural relations between the study variables were then compared across two groups at a time, controlling for installation region, race/ethnicity, marital status, education, and pay grade, resulting in two model comparisons with four coping groups. If the structural weight showed differences across groups, each parameter was constrained and tested one at a time to see where the models are different. Results:, The results showed that the hypothesized model applies across all groups. The structural weights revealed that a moderation effect exists between a group whose tendency is to mostly use positive coping strategies and a group whose tendency is to mostly use negative coping strategies (,,2(39)= 65.116, p<.05). More specifically, the models were different (with and without Bonferroni Type I error correction) in the paths between "motive and alcohol use" and "alcohol use and alcohol-related consequences (job performance)." Conclusions:, It seems plausible that coping style significantly factors into moderating alcohol use among young male military personnel who reportedly drink more excessively than civilians of the same age. The results indicate that it may be particularly important for the military to assess different stress coping styles ofyoung male military personnel so as to limit excessive drinking as well as to promote individual wellness and improve job performance. [source] I. Veterans Affairs Cooperative Study of Polyenylphosphatidylcholine in Alcoholic Liver Disease: Effects on Drinking Behavior by Nurse/Physician TeamsALCOHOLISM, Issue 11 2003Charles S. Lieber Background: This multicenter prospective, randomized, double-blind placebo-controlled trial was designed to evaluate the effectiveness of polyenylphosphatidylcholine against the progression of liver fibrosis toward cirrhosis in alcoholics. Seven hundred eighty-nine alcoholics with an average intake of 16 drinks per day were enrolled. To control excessive drinking, patients were referred to a standard 12-step,based alcoholism treatment program, but most patients refused to attend. Accordingly, study follow-up procedures incorporated the essential features of the brief-intervention approach. An overall substantial and sustained reduction in drinking was observed. Hepatic histological and other findings are described in a companion article. Methods: Patients were randomized to receive daily three tablets of either polyenylphosphatidylcholine or placebo. Monthly follow-up visits included an extensive session with a medical nurse along with brief visits with a study physician (hepatologist or gastroenterologist). A detailed physical examination occurred every 6 months. In addition, telephone consultations with the nurse were readily available. All patients had a liver biopsy before entry; a repeat biopsy was scheduled at 24 and 48 months. Results: There was a striking decrease in average daily alcohol intake to approximately 2.5 drinks per day. This was sustained over the course of the trial, lasting from 2 to 6 years. The effect was similar both in early dropouts and long-term patients, i.e., those with a 24-month biopsy or beyond. Conclusions: In a treatment trial of alcoholic liver fibrosis, a striking reduction in alcohol consumption from 16 to 2.5 daily drinks was achieved with a brief-intervention approach, which consisted of a relative economy of therapeutic efforts that relied mainly on treatment sessions with a medical nurse accompanied by shorter reinforcing visits with a physician. This approach deserves generalization to address the heavy drinking problems commonly encountered in primary care and medical specialty practices. [source] When to say when: can excessive drinking explain silicon uptake in diatoms?BIOESSAYS, Issue 3 2009Kimberlee Thamatrakoln Abstract Diatoms are the single most important drivers of the oceanic silicon biogeochemical cycle. Due to their considerable promise in nanotechnology, there is tremendous interest in understanding the mechanism by which they produce their intricately and ornately decorated silica-based cell wall. Although specific proteins have been implicated in some of the key steps of silicification, the exact mechanisms are poorly understood. Silicon transporters, identified in both diatoms and silicoflagellates, are hypothesized to mediate silicon uptake. Recently, macropinocytosis, the non-specific engulfment of extracellular fluid, was proposed as a more energetically favorable uptake mechanism, which can also explain the long-observed effect of salinity on frustule morphology. We explore the bioenergetic, membrane recycling, and vacuolar volume requirements that must be satisfied for pinocytosis-mediated silicon uptake. These calculated requirements contrast starkly with existing data on diatom physiology, uptake kinetics, growth, and ultrastructure, leading us to conclude that pinocytosis cannot be the primary mechanism of silicon uptake. [source] Die Chemie des Katers: Alkohol und seine FolgenCHEMIE IN UNSERER ZEIT (CHIUZ), Issue 1 2007Klaus Roth Prof. Das Überfluten jeder einzelnen Zelle unseres Körpers mit einer großen Menge Ethanol führt zu Störungen im Stoffwechsel aller Organe. Dies erklärt die große Variationsbreite der Symptome nach zu großer Ethanolaufnahme. Gegen den Kater gibt es keine echte Heilung. "Chemie in unserer Zeit" empfiehlt: Viel reines Wasser gegen den Wasserverlust, eine Aspirin oder Ibuprofen gegen die pochenden Kopfschmerzen, Fruchtsaft gegen den Glucosemangel, Muttis kräftige Hühnerbrühe gegen den Elektrolytverlust, eine Vitamintablette wegen ihres sehr wirksamen Placebo-Effekts, Zuspruch und Mitleidsbekundungen der Lieben und dann , wenn der Kreislauf und die Kontrolle der unteren Extremitäten den aufrechten Gang es zulassen, einen Spaziergang an der frischen Luft. Dabei sollte man intensiv über die Sinnlosigkeit übermäßigen Trinkens nachdenken. Das hilft, und am nächsten Tag ist alles vorbei , zumindest bis zum nächsten Mal. Na dann: Helau und Alaaf! Flooding of every cell in our body with a huge amount of ethanol affects the entire metabolism of all organs. This explains the broad variation of symptoms after drinking to much. There is no real cure für hangover. "Chemie in unserer Zeit" recommends much pure water against the dehydration, aspirin or ibuprofen against the throbbing headaches, fruit juice against hypoglycemia, Mom's powerful chicken soup to compensate for electrolyte losses, a vitamine pill because of its powerful placebo-effect, compassion and words of comfort of the loved ones and finally , if blood circulation and control of the lower extremities admit an upright walk , a long stroll in fresh air. Meanwhile one should think deeply about the pointlessness of excessive drinking. This all helps and on the next day it will all be over , at least until next time. Well then: Cheers and Bottoms up! [source] | |||||||||||||