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R M Davis

Publications and source records attributed to R M Davis.

158 records · Page 9Linked to original sources
PubMedDate not supplied

Pipe smoking in the United States, 1965-1991: prevalence and attributable mortality.

BACKGROUND: National pipe-smoking prevalence data have rarely been reported, and mortality associated with pipe smoking has not been estimated. METHODS: We analyzed National Health Interview Survey data from 1965, 1966, 1970, 1987, and 1991 to estimate adult pipe-smoking prevalence in the United States. For each of these years, we estimated pipe smoking-attributable mortality from chronic obstructive pulmonary disease and cancers of the oral cavity, larynx, esophagus, and lung. RESULTS: From 1965 to 1991, the prevalence of current pipe smoking for men declined 12.1 percentage points (from 14.1% to 2.0%) while pipe smoking remained very uncommon among women. By 1991, pipe smoking was a behavior found primarily among men age 45 years or older. Most men who smoked pipes also used other tobacco products, especially cigarettes. About 830 deaths (range 720-2,495) in 1965 and 1,095 deaths (range 655-2,820) in 1991 were attributable to pipe smoking. CONCLUSIONS: If current trends continue, pipe smoking will become extremely rare in the United States by the year 2000. Reasons for the decline in pipe smoking may include the lack of appeal of pipe smoking to women and adolescents or the increasingly unfavorable image of smoking behavior in general. Prevention and cessation efforts need to be directed against all forms of tobacco, including smokeless tobacco use, cigar smoking, and pipe smoking.

Adult↗
PubMedDate not supplied

Wound healing following anterior keratectomy and lamellar keratoplasty in the pig.

PURPOSE: To examine corneal wound healing in an animal model of two types of mechanical lamellar keratectomy. METHODS: One eye from each of 28 pigs was studied. Using a motorized keratome, corneas were subjected to an anterior lamellar keratectomy with removal of anterior stroma and epithelium, or to automated lamellar keratoplasty (ALK) with reapposition of a corneal flap. The exposed stromal surfaces were labeled intraoperatively with a fluorescent dye (DTAF) to assess deposition of stromal components during subsequent wound healing. Examination before surgery and enucleation included measurement of corneal curvature and intraocular pressure, and assessment of corneal haze. Eyes were prepared for histological examination, fluorescence microscopy, and for fibronectin immunohistochemistry. RESULTS: Both keratectomy procedures produced flattening of corneas by up to 3.80 diopters, 28 days after surgery. Corneal haze was more pronounced in eyes from which epithelium was removed (anterior lamellar keratectomy group). The increased haze in this group was associated histologically with appearance of many reactive keratocytes and inflammatory cells, deposition of new stromal material, and more widespread appearance of fibronectin immunoreactivity. In the lamellar keratoplasty group, only the edges of the corneal wound showed significant reactivity, and included keratocyte activation and epithelial ingrowth. CONCLUSIONS: The pig provides a useful model for studies of refractive surgical techniques using procedures and instruments designed for use in humans. Mechanized keratectomy procedures that minimize disruption of the epithelium and Bowman's layer produce a less reactive corneal wound than procedures in which an expanse of epithelium and anterior stroma are removed.

Animals↗
PubMedDate not supplied

Smoking prevalence in the United States and Taipei City, Taiwan.

Although there are extensive antismoking efforts in the United States, smoking is a largely ignored health issue in Taiwan. In fact, tobacco advertising has increased dramatically since U.S. tobacco was first imported in 1987. We compared estimates of smoking prevalence of 83,281 Americans and 5,023 persons in Taipei, Taiwan, in 1986-1988. Among men, current smoking prevalence was higher in Taipei (49%) than in the United States (29%). In contrast, former smoking prevalence among men was substantially lower in Taipei (5%) than in the United States (32%). Young adults and those with lower and middle education levels had the highest smoking prevalence in both surveys. Among women, the current smoking prevalence was only 8% in Taipei, compared to 25% in the United States. The former smoking prevalence among Taipei women (1%) was also lower than among U.S. women (18%). Our findings indicate the need for expanding antismoking efforts in Taiwan, especially among men and among persons with lower and middle education levels.

Adolescent↗
PubMedDate not supplied

Methods used to quit smoking in the United States. Do cessation programs help?

Using data from the 1986 Adult Use of Tobacco Survey, we analyzed smoking-cessation methods used by adult smokers in the United States who tried to quit. About 90% of successful quitters and 80% of unsuccessful quitters used individual methods of smoking cessation rather than organized programs. Most of these smokers who quit on their own used a "cold turkey" approach. Multivariate analysis showed that women, middle-aged persons, more educated persons, persons who had made more quit-smoking attempts, and, particularly, heavier smokers were most likely to use a cessation program. Daily cigarette consumption, however, did not predict whether persons would succeed or fail during their attempts to quit smoking. Rather, the cessation method used was the strongest predictor of success. Among smokers who had attempted cessation within the previous 10 years, 47.5% of persons who tried to quit on their own were successful whereas only 23.6% of persons who used cessation programs succeeded. We conclude that cessation programs serve a small, but important, population of smokers that includes heavier smokers, those most at risk for tobacco-related morbidity and mortality.

Adolescent↗
PubMedDate not supplied

Interferon-gamma, Staphylococcus aureus, and lipopolysaccharide/silica enhance interleukin-1 beta production by human corneal cells.

Cultures derived from human corneo-scleral rims remaining after a central corneal button had been removed for transplantation, revealed two types of cells on light microscopy: One with typical epithelial morphology and the other resembling fibroblasts. Both cell types contained keratin filaments in early passage and were therefore considered epithelial in nature. The fibroblast-like cells were designated fibroblast-like epithelial cells (FLE) while the typical epithelial cells were referred to as E-type. Both E and FLE cells constitutively produced an IL-1-like factor as determined by thymocyte proliferation assay and IL-2 induction in EL-4 lymphoma cells. Moreover, the supernatants from these cells potentiated concanavalin A (Con A)-primed mitochondrial oxidative metabolism in thymocytes, as indicated by the tetrazolium salt reduction assay (MTT) and this effect was significantly neutralized with monoclonal anti-IL-1 beta. The release of biologically active IL-1 beta by the FLE cells is another characteristic (in addition to the presence of keratin) distinguishing these cells from fibroblasts which do not release biologically active IL-1 beta. Using an ELISA, specific for IL-1 beta, there was clear cut evidence for increased production of this cytokine by FLE cells in response to human recombinant gamma-interferon (IFN-gamma), Staphylococcus aureus, and lipopolysaccharide (LPS) in combination with silica (LPS/silica). Time studies with IFN-gamma and LPS/silica demonstrated that enhanced production was time dependent and that IL-1 beta was primarily cell associated. The results indicate that human corneal E- and FLE-type cells can produce and release IL-1 and that FLE cells can be induced by inflammatory mediators to increase production of IL-1 beta.

Animals↗
PubMedDate not supplied

The distribution of free cigarette samples to minors.

From 1975 through 1984, expenditures by cigarette companies related to the distribution of free cigarette samples increased from $24.2 million to $148.0 million. When adjusted by the consumer price index, expenditures increased more than three-fold. During this period, the proportion of total cigarette advertising and promotional expenditures devoted to sampling increased from 4.9% to 7.1%. To evaluate the degree to which free cigarette samples are distributed to children and adolescents, we surveyed 141 elementary students and 223 high school students in five schools in Chicago in April 1982. We also surveyed a sample of 88 students enrolled at DePaul University in Chicago. Fifty (14%) of the 364 elementary and high school students reported having received free cigarette samples themselves, including six (4%) of the elementary students and 44 (20%) of the high school students. Approximately half of the elementary and high school students, and 28% of the college students, said they had seen children and adolescents receive free cigarette samples. More than three-fourths of the elementary and high school students were opposed to the distribution of free cigarette samples. Seventy-four percent of the college students, including 70% of current smokers, supported an ordinance that would ban cigarette sampling. These data provide evidence that the cigarette industry's voluntary code against distributing free cigarette samples to minors is not being strictly followed. Legislation prohibiting cigarette sampling, which at least 12 cities have adopted, is an effective way to prevent the distribution of free cigarettes to minors.

Adolescent↗
PubMedDate not supplied

Public attitudes about cigarette smoking: results from the 1990 Smoking Activity Volunteer Executed Survey.

The 1990 Smoking Activity Volunteer Executed Survey collected information on a wide range of policy-relevant issues concerning public attitudes about cigarette smoking. These issues include cigarette taxes, advertising restrictions, minors' access to tobacco products, school-based prevention, and exposure to environmental tobacco smoke in workplaces and public areas. Survey data were collected during the spring and summer months of 1990 from random samples of adults from Arizona, Michigan, Pennsylvania, and Texas. Telephone interviews were conducted by trained American Cancer Society volunteers using standardized questionnaires. Cluster sampling techniques, interviewer training and supervision, and data collection procedures were designed in conformity with the methodology of the Behavioral Risk Factor Surveillance System of the Centers for Disease Control and Prevention. Smoking prevalence ranged from a low of approximately 20 percent in Texas to a high of 31 percent in Michigan. Between 60 and 69 percent of the respondents in the four States, including between 44 and 71 percent of current smokers, believe tobacco should be classified as a drug. Around 65 percent of the respondents would support an extra tax on tobacco to finance public campaigns against smoking, and between 61 percent and 69 percent favor banning cigarette advertising in the print media and on billboards. More than 82 percent of the respondents believe that stronger laws should be enacted to prevent the sale of tobacco products to minors, and more than 86 percent believe that existing laws should be better enforced. Current smokers were only slightly less likely than were former and never smokers to indicate support of policy changes to prevent minors'access to tobacco products; the two groups had somewhat more disagreement in the amount of support for the other smoking control policies.Finally, although between 62 and 88 percent of working respondents reported the presence of smoking restrictions at their workplace, between 26 and 48 percent still reported being bothered by smoking at work.These study findings suggest that existing smoking control policies are not restrictive enough or are inadequately enforced. The study documents strong public concern in the four States about the in adequacy of current policies and support for the enactment of stronger legislation to control smoking behavior.

Adolescent↗
PubMedDate not supplied

Criminal deception.

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Adolescent↗