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1.
J Stud Alcohol Drugs ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38830016

RESUMO

OBJECTIVE: Measure prevalence and overlap of secondhand harms from other people's use of alcohol, cannabis, opioid, or other drugs and examine sociodemographic and other correlates of these secondhand harms. METHODS: This cross-sectional analysis used data from 7,799 respondents (51.6% female; 12.9% Black, 15.6% Hispanic/Latiné; mean age: 47.6) in the 2020 U.S. National Alcohol Survey. Secondhand harms included family/marriage difficulties, traffic accidents, vandalism, physical harm, and financial difficulties. Weighted prevalence estimates provided nationally representative estimates of these harms. Logistic regression assessed associations between individual characteristics and secondhand harms. RESULTS: Lifetime prevalence of secondhand harms from alcohol, cannabis, opioid, or other drugs was 34.2%, 5.5%, 7.6%, and 8.3%, respectively. There was substantial overlap among lifetime harms: almost 30% of those reporting secondhand alcohol harms also reported secondhand drug harms. Significant correlates of secondhand substance harms included female sex (alcohol, other drug); white (alcohol, opioid), American Indian/Alaska Native (opioid), and Black (cannabis) race/ethnicity; and separated/divorced/widowed marital status (opioid). Those reporting family history of alcohol problems had significantly higher odds of reporting secondhand harms across substance types. Individuals who reported frequent cannabis use had higher odds of reporting secondhand alcohol and opioid harms compared to those with no cannabis use, (aOR=1.55; aOR=2.38), but lower odds of reporting secondhand cannabis harms (aOR=0.51). CONCLUSIONS: Although less prevalent than secondhand alcohol harms, 14% of participants reported secondhand harms from someone else's drug use and frequently experienced secondhand harms attributed to multiple substances. Population-focused interventions are needed to reduce the total burden of alcohol and drug use.

2.
Sci Robot ; 9(86): eadi2746, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38232146

RESUMO

Versatile programmable materials have long been envisioned that can reconfigure themselves to adapt to changing use cases in adaptive infrastructure, space exploration, disaster response, and more. We introduce a robotic structural system as an implementation of programmable matter, with mechanical performance and scale on par with conventional high-performance materials and truss systems. Fiber-reinforced composite truss-like building blocks form strong, stiff, and lightweight lattice structures as mechanical metamaterials. Two types of mobile robots operate over the exterior surface and through the interior of the system, performing transport, placement, and reversible fastening using the intrinsic lattice periodicity for indexing and metrology. Leveraging programmable matter algorithms to achieve scalability in size and complexity, this system design enables robust collective automated assembly and reconfiguration of large structures with simple robots. We describe the system design and experimental results from a 256-unit cell assembly demonstration and lattice mechanical testing, as well as a demonstration of disassembly and reconfiguration. The assembled structural lattice material exhibits ultralight mass density (0.0103 grams per cubic centimeter) with high strength and stiffness for its weight ( 11.38 kilopascals and 1.1129 megapascals, respectively), a material performance realm appropriate for applications like space structures. With simple robots and structure, high mass-specific structural performance, and competitive throughput, this system demonstrates the potential for self-reconfiguring autonomous metamaterials for diverse applications.

3.
Smart Mater Struct ; 28(5)2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-33479558

RESUMO

Ultralight materials present an opportunity to dramatically increase the efficiency of load-bearing aerostructures. To date, however, these ultralight materials have generally been confined to the laboratory bench-top, due to dimensional constraints of the manufacturing processes. We show a programmable material system applied as a large-scale, ultralight, and conformable aeroelastic structure. The use of a modular, lattice-based, ultralight material results in stiffness typical of an elastomer (2.6 MPa) at a mass density typical of an aerogel (5.6 m g c m 3 ). This, combined with a building block based manufacturing and configuration strategy, enables the rapid realization of new adaptive structures and mechanisms. The heterogeneous design with programmable anisotropy allows for enhanced elastic and global shape deformation in response to external loading, making it useful for tuned fluid-structure interaction. We demonstrate an example application experiment using two building block types for the primary structure of a 4.27m wingspan aircraft, where we spatially program elastic shape morphing to increase aerodynamic efficiency and improve roll control authority, demonstrated with full-scale wind tunnel testing.

4.
Am J Drug Alcohol Abuse ; 45(2): 170-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30495983

RESUMO

BACKGROUND: Partners of heavy drinking individuals can be detrimentally affected as a result of their partner's drinking. OBJECTIVES: The aim of this study was to identify the proportion of heterosexual intimate partner relationships with a heavy drinking male that resulted in reported alcohol-related harm and to investigate the impact of this on well-being in 9 countries. METHODS: This study used survey data from the Gender and Alcohol's Harm to Others (GENAHTO) Project on Alcohol's Harm to Others in 9 countries (10,613 female respondents, 7,091 with intimate live-in partners). Respondents were asked if their partners drinking had negatively affected them as well as questions on depression, anxiety, and satisfaction with life. RESULTS: The proportion of partnered respondents that reported having a harmful heavy drinking partner varied across countries, from 4% in Nigeria and the US to 33% in Vietnam. The most consistent correlate of experiencing harm was being oneself a heavy episodic drinker, most likely as a proxy measure for the acceptability of alcohol consumption in social circles. Women with a harmful heavy drinking partner reported significantly lower mean satisfaction with life than those with a partner that did not drink heavily. CONCLUSIONS: Harms to women from heavy drinking intimate partners appear across a range of subgroups and impact on a wide range of women, at least demographically speaking. Women living with a heavy drinking spouse experience higher levels of anxiety and depression symptoms and lower satisfaction with life.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Relações Interpessoais , Qualidade de Vida , Parceiros Sexuais , Adulto , Feminino , Saúde Global , Humanos , Masculino , Inquéritos e Questionários , Saúde da Mulher
5.
Hisp J Behav Sci ; 39(4): 528-545, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29276337

RESUMO

Objective: Different patterns of heavy drinking occur by country and proximity to the U.S. Mexico border. Few studies describe the impact of violence on drinking between countries and along the border. Methods: Survey data is from U.S. Mexican origin adults living in Texas and Mexican border and non-border cities, N=4,796. Participants were asked about alcohol consumption, interpersonal physical violence (IPV) and exposure to community violence. Monthly hazardous drinking (5+/4+ for men/women) was the primary outcome. Multivariate logistic regression model comparisons identified best predictors. Results: In the U.S. hazardous drinking was associated with past year IPV (ORadj=2.5; 1.8-3.5) and community violence (ORadj=1.4; 1.1-1.8). In Mexico, IPV (ORadj=3.9; 2.0-7.4) and border proximity (ORadj=0.5; 0.4-0.8) were associated with hazardous drinking but not community violence. Conclusion: Hazardous drinking is associated with IPV in both countries, but violence did not explain border hazardous drinking differences where they existed in Mexico.

6.
Ann Oncol ; 22(3): 723-729, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20716625

RESUMO

BACKGROUND: Patients' perspectives provide valuable information on quality of care. This study evaluates the feasibility and validity of Internet administration of Service Satisfaction Scale for Cancer Care (SCA) to assess patient satisfaction with outcome, practitioner manner/skill, information, and waiting/access. PATIENTS AND METHODS: Primary data collected from November 2007 to April 2008. Patients receiving cancer care within 1 year were recruited from oncology, surgery, and radiation clinics at a tertiary care hospital. An Internet-based version of the 16-item SCA was developed. Participants were randomised to Internet SCA followed by paper SCA 2 weeks later or vice versa. Seven-point Likert scale responses were converted to a 0-100 scale (minimum-maximum satisfaction). Response distribution, Cronbach's alpha, and test-retest correlations were calculated. RESULTS: Among 122 consenting participants, 78 responded to initial SCA. Mean satisfaction scores for paper/Internet were 91/90 (outcome), 95/94 (practitioner manner/skill), 89/90 (information), and 86/86 (waiting/access). Response rate and item missingness were similar for Internet and paper. Except for practitioner manner/skill, test-retest correlations were robust r = 0.77 (outcome), 0.74 (information), and 0.75 (waiting/access) (all P < 0.001). CONCLUSIONS: Internet SCA administration is a feasible and a valid measurement of cancer care satisfaction for a wide range of cancer diagnoses, treatment modalities, and clinic settings.


Assuntos
Coleta de Dados/métodos , Neoplasias/terapia , Satisfação do Paciente/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde , Idoso , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Papel
7.
Drug Alcohol Depend ; 110(1-2): 108-16, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20236774

RESUMO

Alcohol consumption causes injury in a dose-response manner. The most common mode of sustaining an alcohol-attributable injury is from a single occasion of acute alcohol consumption, but much of the injury literature employs usual consumption habits to assess risk instead. An analysis of the acute dose-response relationship between alcohol and injury is warranted to generate single occasion- and dose-specific relative risks. A systematic literature review and meta-analysis was conducted to fill this gap. Linear and best-fit first-order model were used to model the data. Usual tests of heterogeneity and publication bias were run. Separate meta-analyses were run for motor vehicle and non-motor vehicle injuries, as well as case-control and case-crossover studies. The risk of injury increases non-linearly with increasing alcohol consumption. For motor vehicle accidents, the odds ratio increases by 1.24 (95% CI: 1.18-1.31) per 10-g in pure alcohol increase to 52.0 (95% CI: 34.50-78.28) at 120 g. For non-motor vehicle injury, the OR increases by 1.30 (95% CI: 1.26-1.34) to an OR of 24.2 at 140 g (95% CI: 16.2-36.2). Case-crossover studies of non-MVA injury result in overall higher risks than case-control studies and the per-drink increase in odds of injury was highest for intentional injury, at 1.38 (95% CI: 1.22-1.55). Efforts to reduce drinking both on an individual level and a population level are important. No level of consumption is safe when driving and less than 2 drinks per occasion should be encouraged to reduce the risk of injury.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/psicologia , Intoxicação Alcoólica/psicologia , Ferimentos e Lesões/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Intoxicação Alcoólica/epidemiologia , Estudos de Casos e Controles , Estudos Cross-Over , Interpretação Estatística de Dados , Relação Dose-Resposta a Droga , Humanos , Razão de Chances , Viés de Publicação , Projetos de Pesquisa , Risco
8.
Am J Epidemiol ; 168(8): 866-71, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18701442

RESUMO

Lifetime abstainers have often been recommended as the comparison group in alcohol epidemiology. The objective of this study was to provide insight into the validity and stability of lifetime abstention by using data derived from the National Alcohol Survey, a national probability survey of US households conducted in 1984, and its 2 follow-up surveys conducted in 1990 and 1992. Results indicated that more than half (52.9%; all proportions were weighted to represent the US population) of those who reported never having a drink of any alcoholic beverage in the 1992 survey reported drinking in previous surveys. Depending on assumptions, this difference may result in an underestimation of alcohol-attributable mortality of 2%-15% in men and 2%-22% in women. Sociodemographic factors differentiated those who consistently reported lifetime abstention across surveys from the rest of the study population. Results suggest that using reported lifetime abstainers as a sole comparison group is problematic, especially if reporting is based on 1 measurement only. Establishing multiple measurement points and including irregular lifetime light drinkers with lifetime abstainers as the comparison group are recommended for future epidemiologic studies.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Grupos Controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Socioeconômicos , Fatores de Tempo
9.
Clin Pharmacol Ther ; 83(4): 640-3, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18305457

RESUMO

Alcohol policy has been shown to have an impact on the incidence and prevalence of alcohol "addiction," or alcohol use disorders (AUDs), as currently defined by the International Classification of Diseases, volume 10, or by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. We will mainly use the term "addiction" to depict a state involving loss of control over intense urges to consume alcohol, even at the expense of adverse consequences. This definition goes beyond pure "physiological dependence." We will use the term AUD when referring to statistics based on the above-described definitions. In this overview we identify the pathways in the relationship between alcohol policy and addiction, present the empirical evidence, and draw conclusions. Special emphasis will be put on treatment policy.


Assuntos
Consumo de Bebidas Alcoólicas , Transtornos Relacionados ao Uso de Álcool , Bebidas Alcoólicas/economia , Benchmarking , Política de Saúde/tendências , Saúde Pública/tendências , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/economia , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Transtornos Relacionados ao Uso de Álcool/terapia , Austrália , Condução de Veículo , Testes Respiratórios , Canadá , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Incidência , Classificação Internacional de Doenças , Prevalência , Impostos , U.R.S.S. , Estados Unidos
10.
Mol Microbiol ; 42(2): 527-37, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11703673

RESUMO

The par stability determinant of the Enterococcus faecalis plasmid pAD1 is the first antisense RNA regulated post-segregational killing system (PSK) identified in a Gram-positive organism. Par encodes two small, convergently transcribed RNAs, designated RNAI and RNAII, which are the toxin and antitoxin of the par PSK system respectively. RNAI encodes an open reading frame for a 33 amino acid toxin called Fst. Expression of fst is regulated post-transcriptionally by RNAII. RNAII interacts with RNAI by a unique antisense RNA mechanism involving binding at the 5' and 3' ends of both RNAs. Par RNA interaction requires a complementary transcriptional terminator stem-loop and a set of direct repeat sequences, DRa and DRb, located at the 5' end of both RNAs. The secondary structures of RNAI, RNAII and the RNAI-RNAII complex were analysed by partial digestion with Pb(II) and ribonucleases. Probing data for RNAI and RNAII are consistent with previously reported computer generated models, and also confirm that complementary direct repeat and terminator sequences are involved in the formation of the RNAI-RNAII complex. Mutant par RNAs were used to show that the binding reaction occurs in at least two steps. The first step is the formation of an initial kissing interaction between the transcriptional terminator stem-loops of both RNAs. The subsequent step(s) involves an initial pairing of the complementary direct repeat sequences followed by complete hybridization of the 5' nucleotides to stabilize the RNAI-RNAII complex.


Assuntos
Enterococcus faecalis/genética , Regulação Bacteriana da Expressão Gênica , Plasmídeos/genética , RNA Antissenso/metabolismo , RNA Bacteriano/metabolismo , RNA/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Dados de Sequência Molecular , Mutação/genética , Ensaios de Proteção de Nucleases , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Fases de Leitura Aberta/genética , RNA/química , RNA/genética , RNA Antissenso/química , RNA Antissenso/genética , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Interferente Pequeno , Ribonucleases/metabolismo , Transcrição Gênica
11.
J Stud Alcohol ; 62(1): 74-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11271967

RESUMO

OBJECTIVE: To assess the effect of mode of administration in alcohol surveys (telephone vs face-to-face interviews), prevalence rates of self-reported harms due to alcohol were compared for two datasets with equivalent measures. METHOD: Two national alcohol surveys were used: the 1990 Warning Labels Survey, in which random digit dialing was used to generate a sample of 2,000 adults interviewed by telephone, and the 1990 National Alcohol Survey (face-to-face interviews), a probability sample of U.S. adults living in households (N = 2,058). Both surveys included identical items on five areas of alcohol-related harm, yielding one composite index of any harm reported in the last 12 months that was compared between the two surveys for current drinkers. RESULTS: After controlling for demographic characteristics and alcohol use, the telephone survey yielded significantly higher rates of alcohol-related health harm, work harm and "any harm" as compared to the in-person survey. The interaction between heavier drinking (five or more drinks during 1 day, weekly or more often) and method of data collection was significant for health harm and any harm. Respondents in the telephone survey who drank 5+ less than weekly were more likely than those interviewed in person to report health harm due to alcohol use; those in the telephone survey who drank 5+ weekly or more often were more likely to report any harm. CONCLUSIONS: Possible explanations for differences between the surveys include anonymity and fewer social desirability issues associated with telephone surveys, as well as potentially differing cognitive requirements in telephone versus face-to-face interviews.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Entrevista Psicológica , Acontecimentos que Mudam a Vida , Inquéritos e Questionários , Telefone , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Masculino , Prevalência
12.
Am J Epidemiol ; 153(1): 64-71, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11159148

RESUMO

The objective of this study was to investigate the effects of an average volume of alcohol consumption and drinking patterns on all-cause mortality. The sample (n = 5,072) was drawn from the 1984 National Alcohol Survey, representative of the US population living in households. Follow-up time was until the end of 1995, with 532 people deceased during this period. The authors found a significant influence of drinking alcohol on mortality with a J-shaped association for males and an insignificant relation of the same shape for females. When the largest categories of equivalent average volume of consumption were divided into people with and without heavy drinking occasions, serving as an indicator of drinking pattern, this differentiation proved important in predicting mortality. Light to moderate drinkers had higher mortality risks when they reported heavy drinking occasions (defined by either eight drinks per occasion or getting drunk at least monthly). Similarly, when the category of exdrinkers was divided into people who did or did not report heavy drinking occasions in the past, people with heavy drinking occasions had a higher mortality risk. Finally, indicating alcohol problems in the past was related to higher mortality risk. Results emphasized the importance of routinely including measures of drinking patterns into future epidemiologic studies on alcohol-related mortality.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Mortalidade , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Masculino , Modelos de Riscos Proporcionais , Fatores de Risco , Assunção de Riscos , Fatores Sexuais , Estados Unidos/epidemiologia
13.
J Dairy Sci ; 84(11): 2469-77, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11768088

RESUMO

Rumen characteristics and digestive kinetics of brown midrib corn silage were evaluated with five late-lactation (221 DIM +/- 20 d) multiparous cows fitted with ruminal and duodenal cannula. Dietary treatments were applied by using a single reversal design with two 21-d periods where either brown midrib (BM3) or isogenic (ISO) corn silage were included in a total mixed ration formulated to be 40% concentrate and 60% corn silage on a dry matter (DM) basis. Rumen and total tract digestibilities of DM, organic matter, neutral detergent fiber, acid detergent fiber, starch, and N were determined and rumen characteristics evaluated. Apparent rumen DM and organic matter digestibilities were greater for the BM3 corn silage (7.1 and 4.7 percentage units, respectively). Dietary intake and duodenal flow of starch were greater and rumen and total tract starch digestibilities were lower for BM3 corn silage diets than ISO corn silage diets. However, more starch (1.1 kg/d) was apparently digested and absorbed postruminally in cows fed the BM3 corn silage diets. Duodenal flow of neutral detergent fiber was 0.9 kg/d lower, and ruminal (15.9 percentage units) and total tract digestibilities (4.4 percentage units) were higher for BM3 treatment compared with the ISO treatment. Digestive patterns of ADF were similar for the BM3 and ISO treatments. Ruminal pH was lower in the cows fed the BM3 corn silage than those fed the ISO corn silage. As a result of a tendency for decreased N excretion in urine and slight increases in N intake due to increased DM intake, N balance tended to be greater for the BM3 treatment compared with the ISO treatment. These results may partially explain the benefits of feeding BM3 corn silage to cows during early lactation, as the observed increases in fiber component digestibility and improved N economy may combine to enhance DM intake and better support the nutritional demands of milk production for the high producing dairy cow.


Assuntos
Bovinos/fisiologia , Trânsito Gastrointestinal/fisiologia , Lactação/metabolismo , Nitrogênio/metabolismo , Rúmen/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/metabolismo , Detergentes/administração & dosagem , Detergentes/metabolismo , Fibras na Dieta/administração & dosagem , Fibras na Dieta/metabolismo , Digestão , Ingestão de Energia , Metabolismo Energético , Feminino , Fermentação , Concentração de Íons de Hidrogênio , Silagem , Amido/administração & dosagem , Amido/metabolismo , Zea mays
14.
Neurology ; 55(11): 1626-35, 2000 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11113215

RESUMO

BACKGROUND: The cause of dementia in subcortical ischemic vascular disease (SIVD) is controversial. OBJECTIVES: To determine whether cognitive impairment in SIVD 1) correlates with measures of ischemic brain injury or brain atrophy, and/or 2) is due to concomitant AD. METHODS: Volumetric MRI of the brain was performed in 1) elderly subjects with lacunes (L) and a spectrum of cognitive impairment-normal cognition (NC+L, n = 32), mild cognitive impairment (CI+L, n = 26), and dementia (D+L, n = 29); 2) a comparison group with probable AD (n = 28); and 3) a control group with normal cognition and no lacunes (NC). The authors examined the relationship between the severity of cognitive impairment and 1) volume, number, and location of lacunes; 2) volume of white matter signal hyperintensities (WMSH); and 3) measures of brain atrophy (i. e., hippocampal, cortical gray matter, and CSF volumes). RESULTS: Among the three lacune groups, severity of cognitive impairment correlated with atrophy of the hippocampus and cortical gray matter, but not with any lacune measure. Although hippocampal atrophy was the best predictor of severity of cognitive impairment, there was evidence for a second, partially independent, atrophic process associated with ventricular dilation, cortical gray matter atrophy, and increase in WMSH. Eight autopsied SIVD cases showed variable severity of ischemic and neurofibrillary degeneration in the hippocampus, but no significant AD pathology in neocortex. The probable AD group gave evidence of only one atrophic process, reflected in the severity of hippocampal atrophy. Comparison of regional neocortical gray matter volumes showed sparing of the primary motor and visual cortices in the probable AD group, but relatively uniform atrophy in the D+L group. CONCLUSIONS: Dementia in SIVD, as in AD, correlates best with hippocampal and cortical atrophy, rather than any measure of lacunes. In SIVD, unlike AD, there is evidence for partial independence between these two atrophic processes. Hippocampal atrophy may result from a mixture of ischemic and degenerative pathologies. The cause of diffuse cortical atrophy is not known, but may be partially indexed by the severity of WMSH.


Assuntos
Isquemia Encefálica/patologia , Córtex Cerebral/patologia , Demência Vascular/patologia , Hipocampo/patologia , Acidente Vascular Cerebral/patologia , Idoso , Atrofia/patologia , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
15.
Mol Microbiol ; 37(3): 652-60, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10931358

RESUMO

The par stability determinant of the Enterococcus faecalis plasmid pAD1 is the first antisense RNA-regulated post-segregational killing system (PSK) identified in a Gram-positive organism. Par encodes two small, convergently transcribed RNAs, designated RNA I and RNA II, which are the toxin and antidote of the par PSK system respectively. RNA I encodes an open reading frame of 33 codons designated fst. The results presented here demonstrate that the peptide encoded by fst is the par toxin. The fst sequence was shown to be sufficient for cell killing, and removal of the final codon inactivated the toxin. In vitro translation reactions of purified RNA I transcript produced a product of the expected size for the fst-encoded peptide. This product was not produced when purified RNA II transcript was added to the translation reaction. Toeprint analysis demonstrated that purified RNA II was able to inhibit ribosome binding to RNA I. These data suggest that fst expression is regulated by RNA II via an antisense RNA mechanism. In vitro translation studies and toeprint analyses also indicated that fst expression is internally regulated by a stem-loop structure at the 5' end of RNA I. Removal of this structure resulted in better ribosome binding to RNA I and a 300-fold increase in production of the fst-encoded peptide. Finally, RNA II was shown to be less stable than RNA I in vivo, providing a basis for the selective expression of fst in plasmid-free cells.


Assuntos
Toxinas Bacterianas/genética , Enterococcus faecalis/genética , Regulação Bacteriana da Expressão Gênica , Plasmídeos/genética , RNA Antissenso/genética , RNA Bacteriano/genética
16.
Mol Microbiol ; 37(3): 661-70, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10931359

RESUMO

The par stability determinant of the Enterococcus faecalis plasmid pAD1 is the first antisense RNA-regulated post-segregational killing system (PSK) identified in a Gram-positive organism. Par encodes two small, convergently transcribed RNAs, designated RNA I and RNA II, which are the toxin and antidote of the par PSK system respectively. RNA I encodes an open reading frame for a 33-amino-acid toxin called Fst. Expression of fst is regulated post-transcriptionally by RNA II. In this paper, RNA II is shown to interact with RNA I by a unique antisense RNA mechanism. RNA I and RNA II contain complementary direct repeats at their 5' ends and a complementary transcriptional terminator stem-loop at their 3' ends. Deletion of the terminator or mutations within the terminator loop of RNA II severely reduced the rate of interaction in vitro. Mutations in the 5' direct repeats of RNA II prevented the RNAs from interacting in vitro. For these mutations in RNA II, complementary mutations in RNA I were shown to restore interaction. The reduced binding efficiency of the RNA II mutants was paralleled by the failure of these mutants to suppress par-mediated killing in vivo. These results indicate that regions at both the 5' and the 3' ends of the par transcripts are important for RNA I-RNA II interaction.


Assuntos
Enterococcus faecalis/genética , Regulação Bacteriana da Expressão Gênica , Plasmídeos/genética , RNA Antissenso/genética , RNA Bacteriano/genética , Regiões 3' não Traduzidas/genética , Regiões 5' não Traduzidas/genética
17.
Addiction ; 95(2): 251-65, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10723854

RESUMO

AIMS: To examine the consistency and/or variability of gender differences in drinking behavior cross-culturally. DESIGN, SETTING, PARTICIPANTS: Women's and men's responses in 16 general population surveys from 10 countries, analyzed by members of the International Research Group on Gender and Alcohol. MEASUREMENTS: Comparable measures of drinking, versus abstention, typical drinking frequencies and quantities, heavy episodic drinking, intoxication, morning drinking, and alcohol-related family and occupational problems. FINDINGS: Women and men differed little in the probability of currently drinking versus abstaining, but men consistently exceeded women in typical drinking frequencies and quantities and in rates of heavy drinking episodes and adverse drinking consequences, while women were consistently more likely than men to be life-time abstainers. In older age groups, both men and women drank smaller quantities of alcohol and were more likely to stop drinking altogether, but drinking frequencies did not change consistently with age. CONCLUSIONS: A theoretical synthesis proposes that gender roles may amplify biological differences in reactions to alcohol, and that gender differences in drinking behavior may be modified by macrosocial factors that modify gender role contrasts.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Transtornos Relacionados ao Uso de Álcool/psicologia , Comparação Transcultural , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
18.
Addiction ; 95(2): 277-84, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10723856

RESUMO

AIMS AND DESIGN: In order to assess the effects of survey modality on alcohol consumption estimates, data from two surveys using different interview modes (face-to-face and telephone) were compared on several alcohol measures. SETTING AND PARTICIPANTS: Face-to-face survey data were drawn from the 1990 National Alcohol Survey, while the telephone data came from the 1990 Warning Labels Survey. Both surveys used a probability sampling of the US adult general population in the 48 contiguous states. MEASUREMENTS: Measures of alcohol use derived from an identical "graduated frequencies" series included estimates of any drinking in the past 12 months, overall volume, and heavy (5+) drinking days. FINDINGS: Abstention rates did not differ by survey mode, nor did distributions of alcohol consumption by volume and reported frequency of drinking five or more drinks in a day. Multiple regression models including demographic-mode interaction terms were used to examine how mode effects might differ across demographic subgroups. Lower income respondents were under-represented in the telephone sample, and were associated with lower reports of volume and 5+ days, compared to respondents in the face-to-face mode. CONCLUSIONS: The results suggest that although there are few differences in alcohol consumption estimates by interview mode, telephone samples may need to be supplemented or estimates adjusted by income level in order to attain equivalent results.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Inquéritos Epidemiológicos , Temperança/estatística & dados numéricos , Viés , Humanos , Entrevistas como Assunto , Análise de Regressão , Telefone , Estados Unidos/epidemiologia
19.
Am J Public Health ; 90(1): 47-52, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10630136

RESUMO

OBJECTIVES: Data from the 1984, 1990, and 1995 National Alcohol Surveys were used to investigate whether declines shown previously in drinking and heavy drinking across many demographic subgroups have continued. METHODS: Three alcohol consumption indicators--current drinking (vs abstaining), weekly drinking, and weekly heavy drinking (5 or more drinks in a day)--were assessed for the total US population and for demographic subgroups. RESULTS: Rates of current drinking, weekly drinking, and frequent heavy drinking, previously reported to have decreased between the 1984 and 1990 surveys, remained unchanged between 1990 and 1995. Separate analyses for each beverage type (beer, wine, and spirits) and most demographic subgroups revealed similar temporal patterns. CONCLUSIONS: Alcohol consumption levels, declining since the early 1980s, may reach a minimum by the 21st century. Consumption levels should be monitored carefully over the next few years in the event that long-term alcohol consumption trends may be shifting.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/tendências , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Estados Unidos/epidemiologia
20.
Am J Public Health ; 90(1): 53-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10630137

RESUMO

OBJECTIVES: Given the decline in alcohol use in the United States since the 1980s, the purpose of this study was to assess shifts in self-reported social consequences of alcohol use (and 5 consequences subscales) and dependence symptoms from 1984 to 1995. METHODS: This study used data from 3 national alcohol surveys based on household probability samples of current drinkers (adults) in 1984, 1990, and 1995; samples sizes were 1503, 1338, and 1417, respectively. RESULTS: Overall, few changes in prevalence of social consequences or dependence symptoms were found. Significantly lower prevalence rates of 2 consequences subscales (accidents/legal problems and work problems) were reported between 1984 and 1990, but prevalence rates did not change for any of the scales from 1990 to 1995. CONCLUSIONS: This stability in alcohol-related outcomes despite reductions in alcohol consumption may be a result of cultural shifts in which problem amplification occurs in "drier" historical periods. Furthermore, rates of alcohol-related problems may be approaching their lowest limit and may not be readily influenced by any additional decreases in alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/epidemiologia , Problemas Sociais , Acidentes/estatística & dados numéricos , Adulto , Idoso , Consumo de Bebidas Alcoólicas/tendências , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Estados Unidos/epidemiologia , Violência/estatística & dados numéricos
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