Biomedical subjects

R L Collins

Publications and source records attributed to R L Collins.

At least 19 recordsLinked to original sources

PubMed2001

A national survey of stress reactions after the September 11, 2001, terrorist attacks.

BACKGROUND: People who are not present at a traumatic event may also experience stress reactions. We assessed the immediate mental health effects of the terrorist attacks on September 11, 2001. METHODS: Using random-digit dialing three to five days after September 11, we interviewed a nationally representative sample of 569 U.S. adults about their reactions to the terrorist attacks and their perceptions of their children's reactions. RESULTS: Forty-four percent of the adults reported one or more substantial stress symptoms; 91 percent had one or more symptoms to at least some degree. Respondents throughout the country reported stress syndromes. They coped by talking with others (98 percent), turning to religion (90 percent), participating in group activities (60 percent), and making donations (36 percent). Eighty-five percent of parents reported that they or other adults in the household had talked to their children about the attacks for an hour or more; 34 percent restricted their children's television viewing. Thirty-five percent of children had one or more stress symptoms, and 47 percent were worried about their own safety or the safety of loved ones. CONCLUSIONS: After the September 11 terrorist attacks, Americans across the country, including children, had substantial symptoms of stress. Even clinicians who practice in regions that are far from the recent attacks should be prepared to assist people with trauma-related symptoms of stress.

Adaptation, Psychological↗

PubMed2001

End-of-life discussions and preferences among persons with HIV.

CONTEXT: Deficits in advance care planning leave many patients and their physicians unprepared for decisions about end-of-life care. Even though the prognosis has improved for many persons with human immunodeficiency virus (HIV) infection, a need for planning remains. OBJECTIVE: To evaluate prevalence of end-of-life discussions, use of advance directives, and preferences concerning end-of-life care and their relationship with patient demographics, clinical status, psychosocial variables, and practitioner characteristics among HIV-infected persons. DESIGN, SETTING, AND PATIENTS: Cross-sectional survey of a US probability sample of 2864, which represents 231 400 adults receiving care for HIV, conducted from January 1996 to April 1997. MAIN OUTCOME MEASURES: Communication with physician regarding end-of-life issues, completion of an advance directive, preference for aggressiveness of care, and willingness to tolerate future permanent adverse health states. RESULTS: A total of 1432 patients (50%) discussed some aspect of end-of-life care with their practitioner and 1088 (38%) completed an advance directive. Patients were more likely to complete an advance directive after a physician discussion (odds ratio [OR], 5.82; 95% confidence interval [CI], 4.50-7.52). Practitioners discussed end-of-life care less with blacks (OR, 0.57; 95% CI, 0.39-0.83) and Latinos (OR, 0.74; 95% CI, 0.55-0.98) than with whites. Women (OR, 1.39; 95% CI, 1.05-1.84) and patients with children in the household (OR, 1.53; 95% CI, 1.12-2.10) communicated the most with practitioners about end-of-life issues. Patients infected with HIV via injection drug use (OR, 0.64; 95% CI, 0.45-0.89) and those with less education communicated the least with physicians about end-of-life issues. Less denial, greater trust in one's practitioner, and longer patient-practitioner relationship were associated with more advance care planning. CONCLUSIONS: Half of all persons infected with HIV are at risk of making end-of-life decisions without prior discussions with their health care practitioners. Blacks, Latinos, intravenous drug users, and less educated individuals need advance care planning interventions in clinical HIV programs.

Adult↗

PubMed2001

Changes in health-promoting behavior following diagnosis with HIV: prevalence and correlates in a national probability sample.

Diet, exercise, smoking, and substance use patterns affect the course of illness and quality of life for people with HIV. In interviews with a national probability sample of 2,864 persons receiving HIV care, it was found that most had made health-promoting changes in one or more of these behaviors since diagnosis. Many reported increased physical activity (43%) and improved diet (59%). Forty-nine percent of cigarette smokers quit or cut down; 80% of substance users did so. Desire for involvement in one's HIV care and information seeking-positive coping were the most consistent correlates of change. Other correlates varied by health practice but included health status, emotional well-being, demographics, and attitudes toward other aspects of HIV care. Most people with HIV improve their health behavior following diagnosis, but more might be helped to do so by targeting these behaviors in future interventions.

Adaptation, Psychological↗

PubMed2001

Binge drinking among underage college students: a test of a restraint-based conceptualization of risk for alcohol abuse.

The authors tested a restraint-based model that binge drinking is a function of being tempted to drink alcohol while also being concerned about avoiding excessive alcohol intake. Underage (18- to 20-year-olds, 204 men and 225 women) college student drinkers completed measures that assessed the attraction to alcohol (e.g., temptation to drink, alcohol expectancies), concern about regulating alcohol intake (e.g., restriction of alcohol intake, reasons for limiting drinking), and alcohol-related outcomes (binge drinking, alcohol problems). In separate hierarchical multiple regressions, the attraction to alcohol accounted for significant amounts of additional variance in each of the alcohol outcomes. Concern about regulating alcohol intake accounted for additional variance, above that explained by attraction to alcohol. The results suggest that interventions for underage binge drinking should include training in the skills for regulating alcohol intake.

Adult↗

PubMed2000

kappa-Opioid receptors in the substantia nigra pars reticulata mediate the U-50,488-induced locomotor activity of preweanling rats.

The purpose of the present study was to determine the neuroanatomical location where kappa-opioid receptor stimulation induces locomotor activity in the preweanling rat. To confirm that the U-50,488-induced locomotor activity of preweanling rats is mediated by kappa-opioid receptors, 18-day-old rats were initially injected with vehicle or the kappa-opioid receptor agonist U-50,488 (5 mg/kg, s.c.) followed, 15 min later, by an injection of the kappa-opioid receptor antagonist nor-binaltorphimine (nor-BNI; 0, 2, 4, 8, or 12 mg/kg, s.c.). In subsequent experiments, 18-day-old rats were injected with vehicle or U-50,488 (5 mg/kg, s.c.) 15 min prior to bilateral administration (0.25 or 0.5 microl per side) of nor-BNI (0, 5, 10, or 20 microg) into the substantia nigra pars reticulata (SNR) or medial dorsal striatum (MDS). In the final experiment, 18-day-old rats received bilateral administration (0.25 microl per side) of vehicle or U-50,488 (0.0, 0.8, 1.6, or 3.2 microg) into the SNR. Results showed that systemically administered nor-BNI (0-12 mg/kg, s.c.) produced a dose-dependent reduction in the U-50, 488-induced locomotor activity of preweanling rats. The site of action for U-50,488's locomotor-activating effects appeared to be the SNR, because (a) bilateral administration of nor-BNI (5, 10, or 20 microg) into the SNR caused a complete attenuation of U-50, 488-induced locomotion, and (b) bilateral administration of U-50,488 into the SNR caused a dose-dependent increase in the locomotor activity of preweanling rats. Striatal injections of nor-BNI did not affect U-50,488-induced locomotor activity. When these findings are considered together it is apparent that stimulation of kappa-opioid receptors in the SNR is both necessary and sufficient for the occurrence of U-50,488-induced locomotor activity in the preweanling rat.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

PubMed2000

Amphetamine treatment during the preweanling period produces enduring changes in striatal protein kinase A activity.

The purpose of this study was to determine whether chronic exposure to amphetamine during the preweanling period causes enduring changes in behavioral and neuronal functioning. In two experiments rats were injected with saline or amphetamine (2.5 or 5.0 mg/kg) on postnatal days (PD) 11-15. Rats then received a challenge injection of saline or 2.5 mg/kg amphetamine on PD 23 or PD 90 and locomotor activity was measured. After behavioral assessment, rats were killed, and their dorsal striata and nucleus accumbens were dissected and later assayed for protein kinase A (PKA) activity. Interestingly, amphetamine treatment during the preweanling period produced an enduring decline in dorsal striatal and accumbal PKA activity that was still apparent in adulthood. These reductions in PKA activity were not related to the occurrence of locomotor sensitization, because rats did not exhibit a sensitized locomotor response when challenged with amphetamine at PD 23 or PD 90.

Animals↗

PubMed2000

Coping, conflictual social interactions, social support, and mood among HIV-infected persons. HCSUS Consortium.

This study considers the interrelationships among coping, conflictual social interactions, and social support, as well as their combined associations with positive and negative mood. Research has shown that each of these variables affects adjustment to stressful circumstances. Few studies, however, examine this full set of variables simultaneously. One hundred forty HIV-infected persons completed a questionnaire containing measures of coping, social support, conflictual social interactions, and positive and negative mood. Factor analyses showed that perceived social support and conflictual social interactions formed separate factors and were not strongly related. Compared to perceived social support, social conflict was more strongly related to coping behaviors, especially to social isolation, anger, and wishful thinking. Conflictual social interactions were more strongly related to negative mood than was perceived social support. Coping by withdrawing socially was significantly related to less positive and greater negative mood. The findings point to the importance of simultaneously considering coping, supportive relationships, and conflictual relationships in studies of adjustment to chronic illness. In particular, a dynamic may occur in which conflictual social interactions and social isolation aggravate each other and result in escalating psychological distress.

Adaptation, Psychological↗

PubMed2000

The role of women's alcohol consumption in evaluation of vulnerability to sexual aggression.

The authors examined the impact of alcohol consumption on women's risk perceptions and intended behaviors in a hypothetical situation in which the potential for establishing a relationship with an attractive man was coupled with the potential for sexual aggression. Fifty-nine single women, ages 21-29, were randomly assigned to 1 of 3 beverage conditions: (a) alcohol (dose sufficient to raise blood alcohol level to .08); (b) placebo, in which they were led to believe that they had consumed alcohol but had not; or (c) no alcohol, in which they neither expected nor received alcohol. Compared with women in the no-alcohol condition, women in the alcohol condition (a) rated the male character in the vignette more positively, (b) anticipated less risk and more benefit resulting from a series of behaviors likely to facilitate the relationship while increasing sexual vulnerability (e.g., engaging in consensual sexual activities), and (c) anticipated greater involvement in those behaviors. The placebo appeared to exert similar but weaker effects.

Adult↗

PubMed2000

Effects of incentive size and timing on response rates to a follow-up wave of a longitudinal mailed survey.

Young adults who had previously participated in a longitudinal survey of youth were sent a questionnaire. They were randomly assigned to receive a $20 prepayment, a $20 postpayment, or a $25 postpayment for participation in the latest survey. Those in the large incentive condition were 7 percentage points more likely to return a survey than those in the smaller, postpayment group. Prepayment had a smaller, less reliable effect. Effects of incentive magnitude and timing were consistent at each month of the study period; only better high school grades distinguished early responders from late responders. Nonresponders had characteristics suggestive of low social conformity and were more likely than responders to be African American and male and have low SES. The discussion centers on motivations for participating in research and differences in the incentives likely to promote continued response versus initial study enrollment.

Adolescent↗

PubMed2000

Temptation, restriction, and the regulation of alcohol intake: validity and utility of the temptation and restraint inventory.

OBJECTIVE: The Temptation and Restraint Inventory (TRI) is a measure of drinking restraint, the preoccupation with controlling alcohol intake. It contains two higher order factors pertaining to the temptation to drink and the restriction of alcohol intake. We tested the convergent and discriminant validity of the TRI in comparison to the Preoccupation with Alcohol Scale (PAS), the Reasons for Limiting Drinking Scale (RLD) and the Drinking-Related Locus of Control Scale (DRIE), each of which measures constructs analogous to the components of the TRI. We also tested the utility of the TRI, as compared to these related measures, for predicting typical drinking and alcohol problems. METHOD: A sample of 296 (50% male) moderate to heavy drinking adults completed the TRI, the PAS, the RLD, the DRIE and measures of typical (weekly) drinking and alcohol problems (SMAST). RESULTS: Correlations indicated that the TRI had excellent convergent and discriminant validity. The TRI's temptation factor (Cognitive and Emotional Preoccupation) was strongly and positively correlated with the PAS and the DRIE, and was weakly and positively correlated with the RLD. The TRI's restriction factor (Cognitive and Behavioral Control) was positively and moderately correlated with the DRIE and moderately to weakly correlated with the PAS and the RLD. In regressions predicting weekly drinking and SMAST scores, the TRI was particularly effective in accounting for the variance in SMAST scores. CONCLUSIONS: In comparison to measures of conceptually related constructs, the components of the TRI showed excellent convergent and discriminant validity. The TRI accounted for large portions of the variance in alcohol-related outcomes, using fewer items than measures of similar constructs.

Adult↗

PubMed1999

Substance use among a regional sample of female nurses.

We assessed the prevalence of licit (e.g. alcohol) and illicit (e.g. cocaine) drug use, as well as prescription (e.g. tranquillizers) and over-the-counter medications (e.g. analgesics), in a regional sample of female nurses. Surveys were mailed to a random sample of 4000 nurses in Western New York. The survey focused on lifetime and current use of substances, negative consequences of alcohol consumption and dependence. Three mailings resulted in a return of 2400 (60%) surveys, of which 1951 (49%) were usable. We examined lifetime and current use in each of the four classes of substances in the context of nursing related-factors (e.g. type of nurse, nursing specialty, work setting) and demographic characteristics (e.g. age, marital status). There were significant differences within each of the different groupings. Lifetime experience of negative consequences were relatively rare and few nurses reported dependence on substances other than tobacco and caffeine.

Adolescent↗

PubMed1999

Effects of repeated methylphenidate treatment in the young rat: sensitization of both locomotor activity and stereotyped sniffing.

The behavioral effects of repeated methylphenidate (MPH) treatment were assessed in young rats. In 4 experiments, rats (starting at Postnatal Day 10 or 16) were pretreated on 5 consecutive days with saline or MPH (2.5-20.0 mg/kg i.p.). Sensitization was assessed after 1 or 7 abstinence days, with rats receiving a test day challenge injection of either a low dose of MPH (2.5 mg/kg) or the same dose of MPH as given during pretreatment. Results show that a test day injection of 2.5 mg/kg MPH produced a sensitized locomotor response in rats pretreated with 2.5-20.0 mg/kg MPH. This MPH-induced locomotor sensitization was evident only after 1 abstinence day. Various pretreatment doses of MPH (5, 10, 15, or 20 mg/kg) were capable of sensitizing the stereotyped sniffing of young rats, but only rats pretreated and tested with the highest dose (20 mg/kg) of MPH showed an augmented stereotyped sniffing response that was still robust after 7 abstinence days. Results indicate that young rats are capable of exhibiting sensitization after an extended abstinence period, which contrasts with previous research suggesting that psychostimulant treatment does not produce long-term sensitization in young rats.

Aging↗

PubMed1999

The modeling of alcohol consumption: a meta-analytic review.

OBJECTIVE: Modeling, or the imitation of another's behavior, has been proposed to influence alcohol consumption. The literature dealing with effects of modeling on alcohol consumption was reviewed using meta-analytic procedures in order to determine the strength of the modeling effect and the variables that moderate the effect. METHOD: Thirteen studies were examined in which participant's alcohol consumption in the presence of a high consumption model was compared to a low consumption model condition or a no-model condition. Analyses were conducted for the four dependent measures utilized in the literature: amount consumed, blood alcohol concentration, number of sips taken and volume per sip. Mean effect sizes (d) were calculated for each dependent measure and moderator variables were examined. RESULTS: Modeling had a significant effect on all four dependent measures, with the strongest effects being on amount consumed and blood alcohol concentration. In addition, analyses identified numerous variables that moderate the effect of modeling on alcohol consumption, including the drinking history of the participant, the drinking task used and the nature of the interaction between model and participant. CONCLUSIONS: Results indicated that modeling has a strong effect on alcohol consumption; however, several variables do mediate this effect.

Adolescent↗

PubMed1999

Adolescent use of illicit drugs other than marijuana: how important is social bonding and for which ethnic groups?

We predicted Grade 12 use of illicit drugs other than marijuana ("hard" drugs) from characteristics at Grade 10, examining the protective value of social bonds and testing whether certain social bonds have greater importance for some racial/ethnic groups. We also explored the association of previous substance use with later "hard" drug use when social bonds and a broad range of other personal and environmental variables are statistically controlled. Bonds with family were inversely related to any use of illicit drugs other than marijuana; various forms of prior use were positively related to both any and frequent use. However, variables other than social bonds and prior use were equal or stronger predictors of both outcomes. Some differences were obtained across racial groups: African-Americans were less likely to use illicit drugs other than marijuana, Mexican-Americans were more affected by family factors than were other groups, and Asian-Americans were more affected by school failure. Implications for prevention are discussed.

Adolescent↗

PubMed1998

Surgical treatment of urate calculi in Dalmatians: 38 cases (1980-1995).

OBJECTIVE: To assess clinical signs and response to surgical treatment in Dalmatians with urate urolithiasis. DESIGN: Retrospective study. ANIMALS: 38 Dalmatians. PROCEDURE: Medical records from 1980 to 1995 of Dalmatians with urate urolithiasis were reviewed to obtain information on history, results of physical examination, hemogram, biochemical analysis, urinalysis, bacterial culture of urine, diagnostic imaging, analysis of calculi, treatment, and recurrence. RESULTS: 35 (92%) dogs were males. Mean age at admission was 4.9 years. Common clinical findings and initial complaints included dribbling of urine, stranguria, vomiting, tense abdomen with signs of pain, and a large bladder. Hematuria was found in 85% of dogs in which urinalysis was performed. Crystalluria was found in 54% of dogs. Bacteria were isolated from urine from 36% of dogs. Contrast radiography and abdominal ultrasonography were the most sensitive diagnostic tests for uroliths. Dogs that underwent scrotal urethrostomy and cystotomy had the fewest number of recurrent clinical signs that were attributable to urinary calculi. Clinical recurrence rate in dogs on a protein-restricted diet was 27%, compared with that (36%) for dogs on a commercial diet. CLINICAL IMPLICATIONS: Urate urolithiasis is more commonly recognized in male Dalmatians compared with females. Contrast radiography and ultrasonography appear to be the most useful techniques for detecting urate uroliths. Scrotal urethrostomy and cystotomy was the most effective surgical treatment for preventing recurrence of clinical signs associated with calculi. Complete removal of calculi and protein-restricted diets may have a beneficial effect in reducing recurrence of calculi.

Animals↗

PubMed1998

Repeated methylphenidate treatment induces behavioral sensitization and decreases protein kinase A and dopamine-stimulated adenylyl cyclase activity in the dorsal striatum.

The behavioral effects of repeated methylphenidate (MPH) treatment were assessed in the adult rat. Protein kinase A (PKA) and adenylyl cyclase (basal and DA-stimulated) activity in the dorsal striatum (i.e., caudate-putamen) were measured to determine whether MPH-induced alterations in these enzymes correlate with the occurrence of behavioral sensitization. In two experiments, adult rats were injected (i.p.) on 5 consecutive pre-exposure days with saline or MPH (5, 10, 15, or 20 mg/kg). Sensitization was tested after a single abstinence day, with rats receiving a challenge injection of MPH prior to either a 40- or 150-min testing session (additional control groups received saline on the test day). Immediately after the 40-min testing session, rats were killed and tissue from the dorsal striatum was dissected for later analysis of PKA and adenylyl cyclase activity. Results showed that repeated MPH treatment sensitized the stereotyped sniffing, but not the locomotor activity, of adult rats. PKA activity was significantly depressed in rats treated with MPH (10 or 20 mg/kg) during both the pre-exposure and test day phases. DA-stimulated adenylyl cyclase activity was reduced after chronic MPH treatment, while basal adenylyl cyclase values were enhanced. Thus, the present study showed that MPH was able to sensitize the stereotyped behaviors of adult rats, an action that corresponded with drug-induced changes in dorsal striatal DA signal transduction mechanisms.

Adenylyl Cyclases↗

PubMed1998

Kappa opioid-mediated behavioral sensitization in the preweanling rat: relationship to Fos immunoreactivity.

When given acutely, drugs that stimulate kappa opioid receptors (e.g., U-50,488) enhance the locomotor activity of preweanling rats and induce regional increases in Fos immunoreactivity (IR). In contrast, the effects of chronic treatment with kappa opioid agonists are unknown. The purpose of the present study was two-fold: first, to determine whether repeated treatment with a kappa opioid agonist would sensitize the locomotor activity of preweanling rats and, second, to determine whether changes in Fos IR correspond with the occurrence of locomotor sensitization. To test these hypotheses, rats were injected with U-50,488 (5 mg/kg, s.c.) or saline on either postnatal days (PD) 5-9 or PD 11-15. For rats pretreated on PD 5-9, a test day injection of U-50,488 or saline was given after either 1 or 7 abstinence days (i.e., at PD 11 or PD 17). For rats pretreated on PD 11-15, a test day injection of U-50,488 or saline was given after 1 abstinence day (i.e., at PD 17). In two additional experiments, the acute and chronic effects of U-50,488 treatment were assessed in adult rats. As expected, repeated treatment with U-50,488 produced locomotor sensitization at both PD 11 and PD 17, but only when the test day occurred 1, and not 7, days after cessation of drug pretreatment. Thus, the persistence of the sensitized response was very brief. Test day treatment with U-50,488 stimulated Fos IR in various brain regions of the preweanling rat, including the medial striatum, nucleus accumbens, lateral habenula, and septal area. Chronic treatment with U-50,488 depressed Fos expression in a number of brain regions (relative to acutely treated rats); however, these changes in Fos IR did not necessarily coincide with the occurrence of behavioral sensitization. Repeated treatment with U-50,488 did not produce locomotor sensitization in adult rats, so Fos IR was not assessed in this age group. Therefore, while acute treatment with U-50,488 both increased locomotor activity and stimulated Fos IR in preweanling rats, chronic U-50,488 treatment produced behavioral changes that did not correspond with Fos expression.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

PubMed1998

Simultaneous polydrug use among teens: prevalence and predictors.

The use of two or more substances in combination, simultaneous polydrug use (SPU), is a particularly dangerous form of drug use that appears to be established by late adolescence. We examined the prevalence of SPU in a diverse sample of 12th graders, and identified risk and protective factors for SPU that are present at 10th grade. We also tested for differences in SPU across race and gender, and explored the basis for observed differences. Our goals were to determine the extent of SPU problems in different groups and how to address these problems. Twenty-nine percent of participants had engaged in SPU in the past year. The best predictors of alcohol/marijuana SPU were a pro-drug environment, pro-drug beliefs, social deviance, and family disruption; only a pro-drug environment was predictive of hard drug SPU. Women were far less likely to combine marijuana and alcohol than were men. Asian Americans were less likely to combine alcohol and marijuana than were other racial groups, apparently due to their advantaged standing on all predictors of this behavior. African Americans were less likely to use hard drugs in combination than were other groups. Overall, polydrug use is a substantial problem for older teens. Broader drug-use prevention programs may be sufficient to address SPU involving gateway drugs, but reducing drug availability appears central to addressing hard drug SPU.

Adolescent↗