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Biomedical subjects

M Crawford

Publications and source records attributed to M Crawford.

At least 55 records · Page 3Linked to original sources
PubMed1999

Inter-ethnic differences in youth tobacco language and cigarette brand preferences.

OBJECTIVE: To describe and understand variations in cigarette brand preferences between adolescents from varying ethnic and gender groups around the US. DESIGN: A qualitative study where adolescents, both smokers and nonsmokers, were interviewed individually in depth. SETTING: Schools and recreation centers in four sites: urban Maryland (Baltimore), urban Texas (Houston), rural Alabama and rural New Mexico. PARTICIPANTS: 121 adolescent volunteers 13-19 years of age, representing African American, white, American Indian and Hispanic ethnic groups, from both genders. RESULTS: Considerable geographic and ethnic variation exists in terminology used by youth to refer to cigarettes and to their use. Clear patterns in brand preference by ethnic group were found that follow patterns of targeted marketing by ethnicity. White teens preferred Marlboro brand cigarettes, while African-American teens who smoke preferred Newports. Hispanic and American Indian teens were more likely to smoke Marlboro or Camel cigarettes. Hispanic teens were most likely to mention low price as a reason for choosing a particular brand or to state that the brand does not matter. Tobacco advertisements targeting ethnic groups and the use of promotional items to encourage teen smoking were also recognized as factors influencing brand preferences. CONCLUSIONS: These findings have implications for the design of intervention programs aimed at curbing teen smoking. When working with teens who already smoke, using youth language to target messages at perceived characteristics of commonly used brands may be more effective and meaningful than talking about cigarette use in general. Another implication of this work is to shed light on what impact an advertising ban would have on teen brand preferences, brand loyalty, and prevalence of smoking.

Adolescent↗
PubMed1999

Recruiting adolescents into qualitative tobacco research studies: experiences and lessons learned.

An increasing barrier to the development and implementation of effective youth smoking prevention and cessation programs involves recruiting adolescents into research studies. Even for non-intervention studies, issues of consent, confidentiality, and motivation to participate are important considerations. In 1996, 11 Prevention Research Center sites across the country conducted qualitative research using focus groups to explore ethnic differences in smoking among adolescents. The diversity in strategies used to interest, motivate, and retain potential focus group subjects provided a rich data set for information about effective strategies and challenges to recruitment. This article presents an overview of recruitment methods used in a multi-site qualitative study on adolescent tobacco use, reports on successful and less successful strategies, and provides recommendations for future recruitment.

Adolescent↗
PubMed1999

One exam--or two?

Explore the source record for details and available documents.

Education, Medical, Graduate↗
PubMed1998

Sleep Deprivation in social phobia and generalized anxiety disorder.

BACKGROUND: Sleep deprivation has been shown to improve depressive symptoms in some patients with major depressive disorder, but it has not been tested in patients with generalized anxiety disorder (GAD) or social phobia (SP). METHODS: To determine if sleep deprivation altered anxiety or depressive symptoms in patients with GAD (n = 7) or SP (n = 8), we sleep deprived patients and normal controls (n = 18) for one night. RESULTS: On one measure of anxiety, GAD patients improved compared with controls, but there were otherwise no significant change differences between controls and SP or GAD patients. CONCLUSIONS: The lack of benefit is consistent with previous findings that sleep deprivation provides no benefit to patients with other anxiety disorders. Sleep deprivation may be a biological intervention that distinguishes anxiety from affective disorders.

Adolescent↗
PubMed1998

Dietary magnesium supplementation attenuates ethanol-induced myocardial dysfunction.

Hypomagnesemia is positively correlated with a number of cardiovascular abnormalities and recent evidence suggests that magnesium supplementation prevents ethanol-induced development of hypertension. The purpose of our study was to assess whether dietary magnesium supplementation effectively reverses or attenuates chronic ethanol-induced cardiac dysfunction, both at the tissue and the cellular level. Therefore, the influence of dietary magnesium supplementation during chronic ethanol ingestion on the mechanical properties of cardiac muscle was studied using isolated papillary muscles and ventricular myocytes from rat heart. In addition, the acute effects of ethanol on cardiac muscle from animals chronically exposed to ethanol in the absence and presence of dietary magnesium supplementation were also examined. Chronic ethanol exposure caused significant cardiac, hepatic, and renal enlargement, increased systolic blood pressure, and produced hypomagnesemia. After chronic ethanol exposure, the baseline force generating capacity of papillary muscles was markedly depressed and was associated with a significant slowing in the maximum velocities of contraction and relaxation. By contrast, in isolated myocytes, long-term ethanol exposure increased the extent of cell shortening associated with a significant reduction in the duration of relengthening and an increase in both the maximum velocities of shortening and relengthening. Dietary magnesium supplementation among animals chronically ingesting ethanol effectively normalized heart size, systolic blood pressure, and reduced plasma ethanol concentration. Magnesium supplementation also attenuated chronic ethanol-induced depression of contractile force and increased the extent of cell shortening. As expected, acute ethanol exposure caused a dose-dependent inhibition of both isometric force and isotonic shortening associated with a decrease in the intracellular calcium transient. However, the extent of the acute ethanol-induced reduction in isometric force and isotonic shortening was always slightly greater among preparations from animals chronically exposed to ethanol. Dietary magnesium supplementation normalized the acute inhibitory action of ethanol on isometric force, isotonic shortening, and the intracellular calcium transient. Our results suggest that dietary magnesium supplementation may attenuate chronic ethanol-induced alterations in baseline myocardial mechanical function and normalize the cardiac response to acute ethanol exposure.

Animals↗
PubMed1997

Role of adenosine in the ethanol-induced potentiation of the effects of general anesthetics in rats.

Acetate, derived from ethanol metabolism in the liver, is released into the circulation and utilized in many tissues including the brain. The subsequent metabolism of acetate results in the production of adenosine that has a number of effects in the central nervous system. The purpose of the present studies, therefore, was to investigate the contribution of metabolically generated adenosine to the ethanol-induced potentiation of the inhalational agents isoflurane and sevoflurane. Changes in the anesthetic requirement for isoflurane and sevoflurane were determined in rats using the tail-clamp procedure. Both ethanol and sodium acetate reduced anesthetic requirement for isoflurane and sevoflurane in a dose-dependent fashion. The effect of acetate on anesthetic requirement was completely blocked by the administration of the adenosine receptor blocker, 8-phenyltheophylline. The ethanol-induced reduction in anesthetic requirement, however, was only partially blocked by 8-phenyltheophylline. Direct intracerebroventricular (i.c.v.) administration of the water-soluble adenosine receptor blocker, 8-sulfophenyltheophylline, also completely blocked the effect of acetate and partially blocked the effect of ethanol. This i.c.v. administration demonstrates that the actions of ethanol and acetate on anesthetic requirement are a central nervous system effect. The i.c.v. administration of the adenosine A1 receptor subtype agonist, R-phenylisopropyl adenosine, potentiated the anesthetic effects of isoflurane and suggests that the A receptor mediates the observed potentiation of anesthetic effect. This is further supported by the concomitant administration of 5-N-ethylcarboxamido adenosine, a non-selective adenosine agonist, with the selective A1 antagonist, 8-cyclopentyltheophylline, showing A1 receptor potentiation of anesthetic requirements. The studies show that (1) acetate potentiates the anesthetic effects of the inhalational anesthetics, sevoflurane and isoflurane; (2) acetate contributes in part to the effect of ethanol on anesthetic potency through metabolically generated adenosine; (3) these effects are likely mediated via adenosine A1 receptor subtypes.

Acetic Acid↗
PubMed1997

Antibodies to OspB prevent infection of C3H mice challenged with Borrelia burgdorferi isolates expressing truncated OspB antigens.

Truncation of outer surface protein B (OspB) of the Lyme disease agent, Borrelia burgdorferi, may allow the organism to escape immunological destruction and render an OspB-based vaccine ineffective. To investigate this possibility, we have identified two isolates, 297 and CA4, which predominantly express a truncated form of the OspB antigen. In each case, nucleic acid sequencing revealed that truncation of the OspB antigen resulted from a nonsense mutation within the 3', end of the ospB gene. Growth inhibition and protection studies demonstrated that both isolates were neutralized by an anti-OspB serum. Our results indicate that truncated forms of the OspB antigen possess epitopes that may represent important targets for neutralizing antibodies and thus, support the inclusion of OspB as a component of a subunit vaccine.

Amino Acid Sequence↗
PubMed1997

Immunization with outer surface protein (Osp) A, but not OspC, provides cross-protection of mice challenged with North American isolates of Borrelia burgdorferi.

The identification of antigens with the capacity to induce a broad spectrum of protective immunity is an important consideration in the design of a Lyme disease vaccine. In this study, the range of protection provided by outer surface protein (Osp) A or OspC vaccination was compared. Mice actively immunized with OspA or OspC were challenged with 3 North American isolates of Borrelia burgdorferi. OspA-immunized mice were fully protected from infection with each of the isolates, whereas mice immunized with OspC were protected from infection with the homologous isolate but not with 2 heterologous isolates. Sequence analysis revealed that the ospA genes from these 3 isolates were >99% homologous, whereas the ospC genes shared only 81%-85% homology. Western blot analysis suggested antigenic heterogeneity associated with OspC but not OspA. These results indicate that genetic and antigenic heterogeneity may limit the usefulness of OspC as a vaccine constituent.

Amino Acid Sequence↗
PubMed1997

Socioeconomic deprivation and health in Glasgow and the west of Scotland--a study of cancer incidence among male residents of hostels for the single homeless.

STUDY OBJECTIVE: To determine the incidence of cancer among homeless men in Glasgow. DESIGN: Descriptive study of cancer incidence in a defined, though individually unidentifiable, population cohort. SETTING: Glasgow and the West of Scotland Region. PARTICIPANTS: Male residents of 10 hostels for the single homeless in Glasgow, open for all or part of the period 1975-93. Estimated total man-years of risk 21,820. MAIN RESULTS: After adjusting for age and socioeconomic deprivation, the proportional incidence ratio (PIR) of tumours of the oral cavity and pharynx in hostel residents was over twice what would be expected in the male population as a whole (PIR 2.37, 95% CI 1.41, 4.00). Cancers of the oesophagus and larynx were also overrepresented (PIR 1.63 and 1.74 respectively). Estimated age standardised incidence ratios were greater than would be expected for the most socioeconomically deprived areas of the west of Scotland for tumours of the oral cavity and pharynx, larynx, oesophagus, and lung (2.39, 1.87, 1.61, and 1.23 respectively). CONCLUSIONS: The incidence of many cancers is known to be higher in lower socioeconomic groups. Within the lowest deprivation category, there is evidence from this study for a further excess risk among homeless men for cancers of the oral cavity and pharynx, oesophagus, larynx, and lung. Improvements in general health care are urgently needed for this particularly vulnerable section of the population.

Cohort Studies↗
PubMed1997

Phase II trial of oral altretamine for relapsed ovarian carcinoma: evaluation of defining response by serum CA125.

PURPOSE: A phase II study was performed of oral altretamine in 71 patients with ovarian carcinoma who entered clinical complete remission with CA125 levels less than 35 U/mL after initial or second-line chemotherapy, and relapsed more than 6 months later. Response was compared between standard and CA125-based criteria. PATIENTS AND METHODS: Altretamine 260 mg/m2 was given in divided doses daily for 14 days per month. Response was evaluated according to European Organization for Research and Treatment of Cancer (EORTC) criteria in 45 of 66 eligible patients. Response was assessed according to precise CA125 criteria in 51 patients based on either a confirmed > or = 50% or > or = 75% decrease in CA125 levels. RESULTS: A combination of domperidone, dexamethasona, and chlorpromazine at night controlled toxicity in most patients, which was mainly nausea (National Cancer Institute criteria grade 2 or 3 in 27), vomiting (grade 2 or 3 in 19, grade 4 in one), and tiredness (grade 2 or 3 in 15). Responses (complete plus partial) were seen in 18 (40%; 95% confidence interval [CI], 25.4% to 54.6%) of those evaluated according to EORTC criteria and in 20 (39%; 95% CI, 25.5% to 52.9%) of those evaluated according to CA125 level. The overall response rate was 26 of 57 (45.6%) and was related to treatment-free interval: 6 to 12 months, 35%; 12 to 24 months, 52%; and greater than 24 months, 67%. The medium duration of response was 8 months. CONCLUSION: Oral altretamine is a useful agent in patients-who relapse after previously responsive ovarian cancer. Response evaluation by a strict CA125 definition gave a similar estimate of the efficacy of altretamine as EORTC criteria.

Administration, Oral↗
PubMed1997

Dialogue. Resource allocation: to those in the greatest need or those who will benefit most?

The behavioral healthcare community seeks universal coverage for mental health and addiction treatment services at parity with coverage for other medical conditions. To achieve this goal, our field must accept and work within realistic financial limits. The time has come to establish a framework for "rational rationing" of behavioral healthcare resources. What are the priorities? How should resources be equitably shared? Should we sacrifice people with mild and moderate disabilities and illness in order to spend most of our dollars on people who are severely impaired? Our first writer, Dr. Daniels, warns us that there are no moral tenets upon which we can easily or comfortably hang our hats, as he shares the current perspective of medical bio-ethics. Dr. Sabin is a practicing psychiatrist at Harvard Pilgrim Health Care. He highlights the Oregon health Plan as one example of political fortitude and wisdom in resolving healthcare resource allocation challenges. Mac Crawford, chairman of the board and chief operating officer of Magellan Health Services, is in one of the most influential positions in private sector integrated behavioral services delivery. He stresses the importance of managed care and clinical process standardization as fundamental requirements for the rational allocation of resources. One additional note: The lack of a consumer voice in this Dialogue is an unfortunate consequence of the mismatch between submissions received and our publication deadlines. It was our intention to present the perspective of a prominent individual from the growing field of consumer and family advocacy. We apologize for the lack of this perspective, which may have extended this discussion to the practical implications of this abstract question of resource allocation.

Cost-Benefit Analysis↗