Heroin self-administration in rats under a progressive ratio schedule of reinforcement

Heroin self-administration behavior under a progressive ratio (PR) schedule of reinforcement was evaluated in rats. The schedule was designed to restrict drug intake, minimize opiate dependency, and quantify the number of responses emitted (final response ratio) in order to receive a limited number of heroin infusions. Final ratios were found to be stable and did not increase with chronic (31 days) PR reinforcement. The ability of the PR schedule to detect changes in heroin reinforcement was demonstrated by evaluating the effect of naltrexone pretreatment and unit dose alteration on final ratios. Naltrexone (0.4 mg/kg) reduced final ratios and an inverted U dose-response relationship was established for the unit heroin doses 12.5–100 µg/injection. Maximal final ratios occurred with 50 µg/injection heroin reinforcement. This PR schedule may provide a useful method for evaluating the effects of pharmacological manipulations or lesions on opiate reinforcement.     

Cigarettes, alcohol and marijuana are related to pyospermia in infertile men

The relationship of current use of cigarettes, marijuana and alcohol to the parameters of seminal fluid analysis, sperm penetration assay and sperm autoimmunity was studied in 164 men from infertile couples. Current cigarette smokers, marijuana users and heavy alcohol users showed greater numbers of leukocytes in the seminal fluid than did nonusers (p less than 0.02, less than 0.007 and less than 0.01, respectively). In addition, cigarette smokers had lower sperm penetration assay scores than nonsmokers (median 2.5 versus 8.0, p = 0.05). Users of cigarettes, marijuana or alcohol showed no decrease in sperm count, motility or percentage of oval sperm, and no difference in prevalence of antisperm antibodies compared to nonusers. After controlling for past sexually transmitted diseases and multiple substance exposures in a multivariate model, use of cigarettes (p = 0.006), marijuana (p = 0.12) or alcohol (p = 0.098) continued to be associated with a trend toward increased number of seminal fluid leukocytes. Cigarette smoking continued to show a significant decrease in sperm penetration assay score (p = 0.03).     

Children's ice hockey injuries.

OBJECTIVE--To determine the rate, type, and severity of injuries to child hockey players as well as assessing coaches', parents', and players' attitudes and knowledge of hockey. DESIGN--A prospective observation of a population's injuries using injury-reporting forms and surveys. SETTING--A community-organized hockey program in Minnesota. PARTICIPANTS: One hundred fifty boys, aged 9 through 15 years, who played ice hockey during the 1990-1991 winter season. MEASUREMENTS AND MAIN RESULTS--Injuries were reported by multiple observers, including coaches, managers, and trained independent observers at the time an injury occurred; coaches, parents, and players were surveyed regarding hockey injuries, knowledge, and attitudes. One in three players experienced an injury during the season. The most common injuries were contusions. Six of 100 players experienced injuries severe enough to require cessation of physical activities for 8 to 25 days or longer. Weight differences of 53 kg and height differences of 55 cm were reported between Bantam-aged players (13 through 15 years), and body contact, including legal checks, accounted for 86% of injuries during games. Illegal checks and violations were associated with 66% of injuries during games, yet only four penalties (14%) were assessed. In addition, one in three games in which an injury resulted was described as hostile and 15% of the injuries were considered intentional. CONCLUSIONS--Eliminating violence and body checking for prepubertal boys while emphasizing rule enforcement and good sportsmanship are recommended.     

The impact of a screening mammography program on Sydney general practitioners

Abstract: The aim of this study was to determine changes in Sydney general practitioners' (GPs) knowledge about, attitude towards and intention to recommend screening mammography over the two years since a screening mammography program was first implemented in the Central Sydney Health Service (CSHS) area. 123 GPs from the CSHS area were selected from a list maintained by the Breast X-ray Programme, while 127 GPs from the rest of Sydney were selected from the Yellow Pages telephone directory. The overall response rate was 84 per cent. Outcomes were assessed by a self-administered questionnaire covering knowledge, attitudes and beliefs, self-report of recent referral practice, intention to recommend, and sources of information about mammography screening. Demographic data were also collected. Results showed that overall knowledge has increased both inside and outside the CSHS area, but important deficiencies in knowledge remain in both areas. Attitudes to screening mammography have improved in the CSHS area, especially regarding the efficacy of screening mammography and patient compliance. Importantly, positive views of screening mammography have declined outside the CSHS area, especially about whether screening mammography can save women's lives. GPs in both areas remain concerned about costs. The presence and strategies of the Breast X-ray Programme have had some positive effect on the attitudes of GPs towards, but not knowledge of, screening mammography.     

Laparoscopic-assisted bowel surgery

The use of laparoscopic surgical techniques is now being applied to a variety of operations traditionally performed in an open fashion. Twenty patients underwent laparoscopic-guided large and small bowel surgery at our institution from March 1991 to April 1992. The indications for surgery included polyps, obstruction, bleeding, and perforation, and pathologic diagnoses included benign polyps, lipomas, inflammatory bowel disease, perforation of a jejunal diverticulum, colonic arteriovenous malformations, and adenocarcinoma. Mobilization of the colon, ligation of the mesentery, and closure of the mesenteric defect were performed using the laparoscopic equipment. One trocar site was enlarged to 3 cm to deliver the bowel through the abdominal wall. All anastomoses were hand-sewn. Postoperative hospitalization ranged from 2 to 31 days (median, five days). No mortality was noted, and morbidity was 20 percent. We conclude that laparoscopic-guided bowel surgery is technically feasible and should translate into shorter hospitalization and less patient discomfort.     

Postpemphigus acanthomata: a sign of clinical activity?

Background Pemphigus is a group of vesiculobullous disorders in which the blisters usually heal with hyper- or hypopigmentation. The appearance of acanthomata at sites of previous blisters has been noted in some cases. Methods All cases of pemphigus admitted to the Madras Medical College hospitals during a 2-year period from March 1993 to March 1995 were taken into the study and screened for the presence of acanthomata. Results Fifty-two cases of pemphigus were identified, 47 of pemphigus vulgaris and five of pemphigus foliaceus; and of these 13 developed acanthomata when the blisters healed. Ten of these cases were of pemphigus vulgaris and three were of pemphigus foliaceus; biopsy of these lesions showed hyperkeratosis, acanthosis, papillomatosis, and intraepidermal clefting. Immunofluorescence carried out in two of these acanthomata also showed intercellular fluorescence. Conclusions The occurrence of acanthomata in healed lesions of pemphigus is not uncommon; because histopathologic and immunofluorescence evidence of disease activity is present, cases of this sort require careful follow-up.