Microstructure and Molecular Interaction in Glycerol Plasticized Chitosan/Poly(vinyl alcohol) Blending Films

Exploring some basic interactions in blending systems is of great significance for designing a blend with controlled structure and properties. This work attempts to analyze microstructure and molecular interaction in glycerol plasticized chitosan/poly(vinyl alcohol) blends by atomic force microscopy, differential scanning calorimetry and ATR‐FTIR spectroscopy. Our results show that the blending films are aggregated by spherical chitosan/poly(vinyl alcohol) blending nanoparticles. The size and aggregation behavior of these particles are closely related to glycerol content. The presence of glycerol gives rise to a continuous closing in T_g of poly(vinyl alcohol) and chitosan components, suggesting an improved miscibility of the blend. Strong hydrogen bonding interaction in the blend is observed and further distinguished by peak resolution. Moreover, more interesting evidence on the effect of glycerol in the blends is provided by monitoring the structure evolution of the blend at different blending steps using atomic force microscopy. The formation of strong hydrogen bonding network among glycerol molecules and polymer matrix was considered as the main driving force to result in the changes in the microstructure and miscibility of the blend.

     

胆胃宁对乙醇性胃黏膜损伤保护作用的实验研究

目的:研究中药胆胃宁对无水乙醇所致胃黏膜损伤的保护作用及作用机制。方法:40只SD大鼠随机分为正常对照组、模型组和胆胃宁低、中、高剂量组共5组。正常对照组和模型组均以1ml生理盐水灌胃,胆胃宁组分别予胆胃宁1ml、2ml、4ml灌胃,2h后除正常对照组外均予无水乙醇灌胃。再过2h后处死大鼠,观察胃黏膜改变并测定溃疡指数及溃疡抑制率以及胃黏膜病理组织学改变,检测胃黏膜丙二醛(MDA)、超氧化物歧化酶(SOD)、前列腺素E2(PGE2)等指标。结果:胆胃宁能减轻乙醇所致胃黏膜损伤,抑制溃疡形成,改善胃黏膜组织学损害。胆胃宁尚可有效抑制乙醇损伤胃黏膜所致的SOD和PGE2降低以及MDA升高,且具有剂量依赖性。结论:胆胃宁可有效预防乙醇所致胃黏膜损伤,其机制可能与减轻脂质过氧化,提高抗氧化活力和PGE2水平有关。     

Moderate Ingestion of Alcohol Is Associated With Acute Ethanol‐Induced Suppression of Circulating CTX in a PTH‐Independent Fashion

The “J shape” curve linking the risk of poor bone health to alcohol intake is now well recognized from epidemiological studies. Ethanol and nonethanol components of alcoholic beverages could influence bone remodeling. However, in the absence of a solid underlying mechanism, the positive association between moderate alcoholic intake and BMD remains questionable because of confounding associated social factors. The objective of this work was to characterize the short‐term effects of moderate alcohol consumption on circulating bone markers, especially those involved in bone resorption. Two sequential blood‐sampling studies were undertaken in fasted healthy volunteers (age, 20–47 yr) over a 6‐h period using beer of different alcohol levels (<0.05–4.6%), solutions of ethanol or orthosilicic acid (two major components of beer), and water ± calcium chloride (positive and negative controls, respectively). Study 1 (24 subjects) assessed the effects of the different solutions, whereas study 2 (26 subjects) focused on ethanol/beer dose. Using all data in a “mixed effect model,” we identified the contributions of the individual components of beer, namely ethanol, energy, low‐dose calcium, and high‐dose orthosilicic acid, on acute bone resorption. Markers of bone formation were unchanged throughout the study for all solutions investigated. In contrast, the bone resorption marker, serum carboxy terminal telopeptide of type I collagen (CTX), was significantly reduced after ingestion of a 0.6 liters of ethanol solution (>2% ethanol; p ≤ 0.01, RM‐ANOVA), 0.6 liters of beer (<0.05–4.6% ethanol; p < 0.02), or a solution of calcium (180 mg calcium; p < 0.001), but only after calcium ingestion was the reduction in CTX preceded by a significant fall in serum PTH (p < 0.001). Orthosilicic acid had no acute effect. Similar reductions in CTX, from baseline, were measured in urine after ingestion of the test solutions; however, the biological variability in urine CTX was greater compared with serum CTX. Modeling indicated that the major, acute suppressive effects of moderate beer ingestion (0.6 liters) on CTX were caused by energy intake in the early phase (～0–3 h) and a “nonenergy” ethanol component in the later phase (～3 to >6 h). The early effect on bone resorption is well described after the intake of energy, mediated by glucagon‐like peptide‐2, but the late effect of moderate alcohol ingestion is novel, seems to be ethanol specific, and is mediated in a non–calcitonin‐ and a non–PTH‐dependent fashion, thus providing a mechanism for the positive association between moderate alcohol ingestion and BMD.     

The crown of love: intimate relations and alcohol use in adolescence

Background  Remarkably, little attention has been paid to the role of intimate partners and their drinking behavior in relation to adolescent alcohol use. In the current study, we examined associations between adolescent alcohol use and romantic partners’ drinking behavior. Methods  A total of 428 families, consisting of both parents and two adolescents (aged 13.4 and 15.2 at Time 1) participated in a prospective study with four annual waves. Correlations and multivariate regressions were used to examine (1) similarity in drinking behaviors of adolescents and intimate partners, (2) whether alcohol use of partners prospectively predicts adolescent alcohol consumption, and (3) whether adolescents who consume alcohol select partners over time who show similar drinking behaviors. Results  (1) Frequency of alcohol consumption of adolescents and of their romantic partners correlated significantly. (2) Alcohol use of partners was not predictive of adolescent alcohol consumption over time, if previous levels of alcohol consumption were taken into account. (3) Adolescents acquired partners with similar drinking behaviors. Gender effects were found; adolescent girls, but not boys, were more likely to become involved with partners who also frequently consumed alcohol. Conclusions  Regarding alcohol consumption, adolescents and their intimate partners were relatively similar in alcohol use. This resemblance is best explained by adolescents’ selection of future partner on the basis of alcohol consumption. Less indication was found for influence effects, perhaps due to the transient nature of most adolescent romantic relationships.

The association between harmful alcohol use and Internet addiction among college students: Comparison of personality

Aims:  This study aimed to (i) evaluate the association between Internet addiction and harmful alcohol use, and (ii) evaluate the associated personality characteristics of Internet addiction as well as harmful alcohol use.
Methods:  A total of 2453 college students were invited to complete the Chen Internet Addiction Scale, Behavior Inhibition System and Behavior Approach System Scale(BIS/BAS scale), and the Alcohol Use Disorders Identification Test from May 2005 to May 2006.
Results:  The results demonstrated Internet addiction was associated with harmful alcohol use among college students. College students with Internet addiction had higher scores on the BIS and BAS fun-seeking subscales. However, college students with harmful alcohol use had higher scores on the BAS drive and fun-seeking subscales, and lower scores on the BIS subscale.
Conclusions:  Internet addiction is associated with harmful alcohol use. Furthermore, fun seeking was the shared characteristic of these two problem behaviors and might contribute to the association. However, further studies are necessary to evaluate the underlying mechanisms accounting for the association between Internet addiction and harmful alcohol use.     

Prevalence and identification of alcohol use disorders among severe mental illness inpatients in Taiwan

Aims:  A higher prevalence of alcohol use disorders (AUD) among psychiatric patients has been reported previously and the identification rate is relatively low. This study was designed to investigate the prevalence and identification of AUD among acute psychiatric inpatients with severe mental illness in a psychiatric hospital in Taiwan.
Methods:  In a two-phase case identification strategy, the Alcohol Use Disorders Identification Test (AUDIT) was used as the first phase screening tool and the Structured Clinical Interview for DSM-IV-TR as the second phase diagnostic interview. The definition of identification was diagnosis of AUD on medical record at discharge.
Results:  Of 400 respondents, 42 screened positive and 358 screened negative. All screen-positive respondents and 35 screen-negative respondents entered the second phase interview. The weighted lifetime prevalence of alcohol dependence was 8.3% (95% confidence interval [CI]: 4.6–11.9%); alcohol abuse, 1.5% (95%CI: 0.2–2.8%); and AUD, 9.8% (95%CI: 5.7–13.8%). The overall identification rate of AUD by medical staff was 28.2% (0% for alcohol abuse and 33.3% for alcohol dependence). Patients with mood disorders were prone to being undetected as having AUD.
Conclusion:  AUD comorbidity was common among inpatients with severe mental illness in Taiwan and was easily neglected by medical staff. It is necessary to use a validated screening questionnaire, such as AUDIT, to detect high-risk patients and then give appropriate interventions to enhance treatment outcome.     

Alcohol-specific rules, personality and adolescents' alcohol use: a longitudinal person-environment study

AIMS: To examine the bi-directional associations between providing alcohol-specific rules and adolescents' alcohol use. Further, to explore person-environment interactions, we tested whether Big Five personality traits moderate the assumed association between providing alcohol-specific rules and adolescents' alcohol use. DESIGN: Longitudinal data (three waves in 2 years) from 428 families, consisting of both parents and two adolescents (aged 13-16 years) were used for the analyses. Analyses were conducted on four samples: a group of older adolescents and a group of younger adolescents who already consumed alcohol, and a group of older and younger adolescents who were not drinking at baseline measurement. FINDINGS: In general, results of structural equation modelling showed that providing clear alcohol-specific rules lowers the likelihood of drinking initiation, regardless of the age of the youngsters. Once adolescents have established a drinking pattern, the impact of parental alcohol-specific rules declined or even disappeared. Finally, the Big Five personality traits did not moderate the association between providing alcohol-specific rules and adolescents' alcohol involvement. CONCLUSIONS: In sum, in particular during the initiation phase of drinking, parents could prevent the drinking of their offspring, regardless of the age or personality of their youngsters, by providing clear alcohol-specific rules.     

Japan: alcohol today

AIMS: The purpose of this paper is to outline alcohol availability, alcohol consumption and related harm, alcohol control policy and prevention programmes in Japan, few of which have been discussed in either the Japanese or English literature. METHODS: Data were collected primarily from the following two sources: statistics and survey results issued by the national government, including surveys funded by the government; and papers published since 2000, identified by searching the MEDLINE and Igaku-Chuo-Zasshi databases. These data were assessed regarding their quality and summarized. Some data presented here were produced specifically for this review. RESULTS: Although per capita alcohol consumption has tended to decline for more than 10 years, it has remained at a high level. Diversification of the drinking population has progressed rapidly, specifically in women, among whom alcohol consumption has increased sharply. Cross-sectional data suggest that alcohol consumption is associated with serious health and social consequences. Existing longitudinal data suggest that alcohol-related problems, especially health problems, have increased steadily over the past several decades, with few exceptions, including alcohol-related fatal road traffic accidents. Alcohol policy and prevention programmes have not developed to a level that can control these problems adequately. Specifically, the high availability of alcoholic beverages, including the lack of restrictions on sales and advertising and decreasing prices, are noted. CONCLUSIONS: This review provides basic information regarding alcohol availability and alcohol consumption and related harm that may facilitate the improvement of existing alcohol control measures in Japan and encourage the development of new alcohol control measures. This research revealed the scarcity of longitudinal data regarding alcohol consumption and its consequences, and the lack of several important variables, such as disability adjusted life years, for improving our understanding of the comprehensive status of alcohol in Japan.     

The monoamine oxidase A (MAO-A) gene, family function and maltreatment as predictors of destructive behaviour during male adolescent alcohol consumption

AIM: To investigate possible interactions between a polymorphism in the monoamine oxidase A (MAO-A) gene promoter, family relations and maltreatment/sexual abuse on adolescent alcohol-related problem behaviour among male adolescents. DESIGN, SETTING AND PARTICIPANTS: A cross-sectional study of a randomized sample of 66 male individuals from a total population of 16- and 19-year adolescents from a Swedish county. Boys, who volunteered to participate answering an alcohol-related problem/behaviour questionnaire, were investigated with regard to interactions between such problems, family function, maltreatment and MAO-A genotype. MEASUREMENTS: MAO-A genotype, family relations history, history of being maltreated or abused and alcohol-related problem behaviour. FINDINGS: Boys with the short (three-repeat) variant of the MAO-A gene, who had been maltreated/abused or came from families with poor relations, showed significantly higher scores of alcohol-related problems. We also found that maltreatment/abuse independently showed the strongest relation to alcohol-related problems among boys in our model. CONCLUSIONS: The results suggest that both maltreatment and MAO-A genotype may be useful for the understanding of male adolescent alcohol-related problem behaviour.