Search PubMed⌕ Search

Biomedical subjects

P Demers

Publications and source records attributed to P Demers.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Comparison of hemodynamic and ventilatory effects of pneumoperitoneum using carbon dioxide or abdominal suspension during laparoscopic cholecystectomy].

This study compares the cardio-respiratory effects of CO2 pneumoperitoneum to those of abdominal suspension (or laparolift) in laparoscopic cholecystectomy. Between september 1993 et may 1995, 31 patients participated in this non-randomized prospective trial. They consisted of 9 males et 22 females, with a mean age of 47.0 +/- 14 years. Sixteen patients were included in the CO2 group and 15 in the laparolift group. Both groups were comparable for age and gender. All patients were submitted to the same anaesthetic protocol. Repeated measurements of the respiratory and cardiovascular function were made during the intervention. End tidal CO2, minute ventilation, peak inspiratory pressure showed superior elevations in the CO2 group. And for the hemodynamic parameters, only the mean arterial pressure and cardiac frequency differed between the two groups, other hemodynamic parameters including left ventricular ejection fraction were comparable. Also, postoperatory hospital stay, OR time, per and postoperatory complications were comparable. With its stable hemodynamic and ventilatory pattern, abdominal suspension can constitute a safe and secure alternative to CO2 pneumoperitoneum in patients with respiratory dysfunction.

Adult↗
PubMed1994

Translation of clinical and neuropsychological instruments into French: the CERAD experience.

The increasing number of international and epidemiological studies of Alzheimer's disease points to the need for linguistically equivalent translations of measures for identifying the presence, types, and severity of dementia in cross-cultural populations. In translating the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuropsychological instruments into French, several linguistic issues have emerged such as semantic, phonetic, and word-frequency equivalences. In verbal memory tests, these problems, though minor in appearance, can be major pitfalls in studies comparing cognitive function in populations differing in language. Description of the translation procedure and examples of problems encountered are presented, with measures taken to resolve them.

Aged↗
PubMed1992

Neuropsychological performance among agricultural pesticide applicators.

To assess the potential effects on neuropsychiatric performance of chronic occupational exposure to organophosphate insecticides, we performed a prospective longitudinal study of a cohort of apple orchard pesticide applicators and a comparison cohort of beef slaughter-house workers. The study group consisted of 49 applicators and 40 comparison subjects who completed both an initial evaluation (preseason) prior to the onset of the approximately 6-month pesticide spraying season and a follow-up evaluation (postseason) about 1 month following the end of spraying season. The applicator cohort had a greater number (n = 22, 45%) of individuals who identified primary preference for Spanish-language testing than did the comparison cohort (n = 5, 13%). Stratification by language preference revealed no significant differences in background characteristics between the two cohorts, except for fewer years of education in the Spanish-language preference applicators versus control subgroups (5.0 +/- 3.1 vs 7.8 +/- 3.7 years, respectively). After controlling for language preference, there were no statistically significant differences between the applicators and control cohorts on neuropsychological subtests of the computerized test battery. Preseason baseline performance on individual tests was a significant predictor of postseason test performance. After controlling for baseline performance, the only statistically significant exposure related across-season changes in neuropsychological performance was for one subtest (Symbol Digit Substitution) and was confined to the Spanish language preference subgroups, with worse adjusted postseason performance among applicators versus controls (P = 0.001). This study found no clear evidence of clinically significant decrements in neuropsychological performance following one 6-month season of pesticide exposure in a cohort of applicators who were felt to have generally low, intermittent, and well-controlled organophosphate exposures.

Adult↗
PubMed1992

Organophosphate pesticide exposure in a group of Washington State orchard applicators.

As part of a study to investigate the potential for organophosphates to cause chronic neurologic sequelae, we assessed the pesticide exposure experience of a group of Washington State apple orchard applicators. Seasonal monitoring of cholinesterase activity for 48 regular organophosphate applicators and a control group of 40 slaughterhouse workers was performed. A subset of the pesticide applicators participated in an in-depth exposure assessment. This involved observation of spraying activities during 1 spray day, as well as cholinesterase monitoring and dermal exposure assessment using a fluorescent tracer in the pesticide formulation. Comparison of seasonal red blood cell cholinesterase change in pesticide workers according to exposure level, characterized by frequency of pesticide spraying and protective equipment use, showed lower cholinesterase levels among higher exposed groups compared to lesser exposed groups. In-depth exposure assessment revealed exposure primarily on the head and hand regions. Subclinical changes (less than 15% inhibition) in red cell cholinesterase correlated well with dermal exposure calculations. This study suggests that cholinesterase monitoring may be a useful biological marker for even subclinical organophosphate pesticide effects.

Agricultural Workers' Diseases↗
PubMed1991

Opposite variations of two epididymal components and blood plasma testosterone in two breeds of rams.

1. Testicular volume (T Vol), blood plasma testosterone (T) concentration, seminal plasma alpha-glucosidase (alpha-G) specific activity, L-carnitine (L-C) concentration as well as semen characteristics were compared in eight Finnish Landrace (F) and eight Suffolk (S) rams throughout 21 months. 2. Only T Vol and T exhibited a typical seasonal variation in both breeds, whereas L-C, alpha-G and live sperm output presented a seasonal profile only in S rams. 3. L-C and alpha-G variations were opposite to those of T in S rams, while they fluctuated in F rams throughout the entire experiment, as did live sperm output. 4. Only the number of ejaculates and T were significantly higher in F rams (3.50 +/- 0.08 in 5 min and 7.62 +/- 0.40 ng/ml) than in S rams (2.30 +/- 0.05 in 5 min and 5.5 +/- 0.30 ng/ml); these two characteristics might therefore be considered as two indexes of sexual activity in rams. 5. By contrast, among all characteristics measured, only alpha-G was significantly higher in S rams than in F rams (1.33 +/- 0.04 vs 0.77 +/- 0.03 mU/mg proteins); this result, as well as seasonal alpha-G profile present in only S rams, allowed us to conclude that alpha-G might be considered as an additional index of seasonal reproduction in rams.

Animals↗
PubMed1991

Occupational injuries and illnesses among Washington State agricultural workers.

In Washington state 29,451 workers' compensation claims were filed by farm workers between 1982 and 1986. Five percent of claimants were under 18 years of age, including 1.3% under the age of 16. Agricultural workers were found to be at higher risk than other workers in the state for fatal injury (relative risk [RR] = 2.5, 95% confidence interval [CI] = 1.7-3.7), sprains and strains (RR = 1.4, CI = 1.3-1.4), fractures (RR = 2.3, CI = 2.2-2.4), dislocations (RR = 1.9, CI = 1.7-2.2), concussions (RR = 1.9, CI = 1.6-2.3), amputations (RR = 2.5, CI = 2.0-3.1), dermatitis (RR = 4.3, CI = 4.0-4.7), systemic poisoning (RR = 3.4, CI = 3.1-3.7), respiratory disease (RR = 1.7, CI = 1.0-2.9), and tendonitis (RR = 1.2, CI = 1.1-1.4).

Absenteeism↗
PubMed1991

The effects of removing a statutory barrier to workers' compensation for farm workers.

In 1983 the Washington State Supreme Court ruled unconstitutional a unique exemption that excluded farm workers from workers' compensation if they had not earned $150 in continuous work with the same employer. In order to examine the effect of removing this restriction, workers' compensation data were analyzed to examine the number of farm workers covered, the number of claims submitted, and claim acceptance rates before and after the ruling. Although the 1983 ruling appears to have had a significant impact on the treatment of claims, no increase in utilization of the workers' compensation system was observed. Further intervention is required if the objective of treating farm workers equitably is to be realized.

Agricultural Workers' Diseases↗
PubMed1990

Cohort mortality study of Seattle fire fighters: 1945-1983.

Fire fighters are known to be occupationally exposed to many toxic substances. However, the limited number of previous studies has not demonstrated any consistent excess mortality from diseases of a priori concern, such as lung cancer, non-malignant respiratory disease, and cardiovascular disease. We studied 2,289 Seattle fire fighters from 1945 through 1983, and observed 383 deaths. Excess mortality from leukemia (SMR = 503, n = 3) and multiple myeloma (SMR = 989, n = 2) was observed among fire fighters with 30 years or more fire combat duty. Lung cancer mortality was elevated (SMR = 177, n = 18) among fire fighters 65 years old or older. We also analyzed the data by considering fire fighters at risk only after 30 years from first exposure. In this analysis, a trend of increasing risk with increasing exposure was observed for diseases of the circulatory system. For this cause of death, fire fighters with 30 years or more fire combat duty had a relative risk of 1.84 compared to those with less than 15 years of fire combat duty.

Cause of Death↗
PubMed1990

The corpus callosum and cerebral speech lateralization.

In order to specify the callosal involvement in the establishment of cerebral lateralization, a dichotic listening task was administered to six subjects with congenital absence of the corpus callosum, two callosotomized patients, and two hemispherectomized patients. The acallosal subjects were also compared to six subjects matched for age, sex, and hand dominance as well as to six subjects also matched for IQ. Our findings indicate that language functions, as assessed by dichotic listening performance, are more strongly lateralized in callosal agenesis subjects than in IQ-matched normal controls. Our results also reveal that hemispherectomized patients typically show a strong ear-advantage favoring the ear contralateral to their remaining hemisphere. Callosotomized patients, on the other hand, show a more variable pattern of results that seems to be related to the postsurgical time interval. Finally, our findings suggest that there might be a relationship between IQ and lateralization in subjects with borderline or mild deficiency.

Adolescent↗
PubMed1990

Respiratory mortality among firefighters.

Although firefighters have been shown in some studies to suffer chronic respiratory morbidity from their occupational exposures, an increased risk for dying from non-malignant respiratory diseases has not been documented in any previous retrospective cohort mortality study. In order to assess the possibility that an unusually strong "healthy worker effect" among firefighters might mask this increased risk, a mortality analysis of firefighters was carried out in three cities in relation to the United States population and also to a comparison cohort of police officers. The firefighters were employed between 1945 and 1980 and experienced 886 deaths by 1 January 1984; compared with the United States population they had a significantly reduced risk of dying from all causes (SMR = 82, 95% confidence interval, 77-87), and from non-malignant circulatory diseases (SMR = 81, 95% confidence interval 73-89), but no significant difference in risk of non-malignant respiratory diseases (SMR = 88, 95% confidence interval 66-117). Compared with police, the firefighters experienced a trend toward improved mortality outcomes for all causes investigated (SMR = 82), but they had an excess of deaths from non-malignant respiratory diseases (SMR = 141). The results indicate that firefighters are probably at increased risk for dying from non-malignant respiratory diseases; this increased risk may have been missed in previous studies because of the limitations of using a general reference population.

Adolescent↗
PubMed1990

Alpha-1,4-glucosidase activity in ram seminal plasma is inversely related to serum testosterone.

The epididymis of adult rams is the primary source of alpha-glucosidase in seminal plasma. Two breeds of rams were selected to ascertain whether the enzyme was under androgenic control during adult life of rams. Opposite variations between serum testosterone and alpha-glucosidase were recorded over a period of 16 months in Suffolk and Finnish Landrace. In addition, the highest percentage of sperm motility was associated with a low alpha-glucosidase content of seminal plasma. Data from this study suggest that seasonal variations of testosterone in adult rams exert a negative control on the presence of alpha-glucosidase in semen.

Animals↗
PubMed1988

Serum cholesterol and colorectal polyps.

Colorectal cancer and hypocholesterolemia have recently been associated, and colorectal polyps have a known relationship with colorectal cancer. In order to establish further evidence regarding the nature of the serum cholesterol-colorectal cancer relationship, this study investigated the hypothesis that men with colorectal polyps would have lower serum cholesterol levels than men without polyps. Of the 1380 men screened by sigmoidoscopy for colorectal polyps, 246 had at least one polyp. The men with polyps were older than those without, and also had higher cholesterol levels, but after controlling for age, there were no serum cholesterol differences. These data suggest that low serum cholesterol is not etiologically linked to cancer. Analyses of potentially confounding variables showed smoking to be strongly related to the presence of polyps.

Adult↗
PubMed1986

New-patient no-shows in an urban family practice center: analysis and intervention.

The new-patient no-show rate reached 55 percent in an urban, university-based family practice center in mid-1981. A prospective descriptive study revealed that the no-show rates varied significantly with hour of appointment, patient age, source of referral, delay in appointment date, and chronicity of illness. Study findings led to alterations in the scheduling system, with a subsequent drop in the new-patient no-show rate to 40 percent.

Adult↗
PubMed1985

Relative sensitivity of the fecal occult blood test and flexible sigmoidoscopy in detecting polyps.

A group of 1,002 male pattern and model makers, an occupational group at high risk for colorectal cancers, was screened for the presence of polyps and malignancies of the lower gastrointestinal tract. Flexible sigmoidoscopy and serial fecal occult blood testing were both performed on 988 of the participants, and 165 were found to have at least one colorectal polyp. Only 3% of all men with visualized polyps showed Hemoccult-positive stools. Only 2 (4%) of the 51 men with histologically proven adenomatous polyps were Hemoccult positive. Adenomatous polyps of 1 cm or greater in diameter are malignant 8% of the time. This study concludes that the fecal occult blood test sensitivity in detecting colorectal polyps is unacceptably low. It should be supplemented by more rigorous procedures, especially in populations at high risk for colorectal cancer.

Adolescent↗
PubMed1985

Prevalence of colorectal polyps among Michigan pattern and model makers.

A group of 902 pattern and model makers were screened for colorectal cancer and polyps using a 60-cm flexible sigmoidoscope. Three recent mortality studies have found a significant excess of colorectal malignant neoplasms in this occupational group. Four adenocarcinomas, two carcinoids, and two cancers in situ were found. In addition, 150 (17%) of the individuals were found to have polyps. Among white males 40 to 70 years of age, the prevalence rate was found to be 23%. The prevalence of colorectal polyps among the pattern and model makers was compared with that of four previously studied asymptomatic populations who were also examined using a 60-cm flexible sigmoidoscope. Polyp rates were found to be significantly greater among pattern and model makers than among three of the four comparison populations. The odds ratios between these three populations and the study population ranged from 1.9 to 2.7 and closely approximate the ratios found in previous studies evaluating colon cancer in this occupational group.

Adenocarcinoma↗
PubMed1985

Leptospiral exposure in Detroit rodent control workers.

Antibody levels to L. icterohemorrhagiae of rodent control workers and two control groups were compared with antibodies against five other leptospiral serotypes carried predominantly by species other than rats. Rodent control workers contact urban rats, 77 per cent of which are carriers of leptospiral organisms. Rodent control workers had higher antibody levels against L. icterohemorrhagiae than control groups (OR 4.37, 99 per cent CI = 3.0, 6.3 and OR 11.08, 99 per cent CI = 5.6, 22). Antibodies against the other five serotypes were almost non-existent in the study group.

Adult↗
PubMed1983

Exposure to Leptospira icterohaemorrhagiae in inner-city and suburban children: a serologic comparison.

This study explores the exposure of urban children to the spirochete Leptospira icterohaemorrhagiae. This organism is carried by 90 percent of the rats in Detroit. It is felt that these rats are a potential vehicle for childhood exposure to this organism. Strain-specific tests were performed comparing antibody levels in sera of inner-city (exposed) and suburban (unexposed) children. Study and control groups, numbering 124 and 113, respectively, showed significant serologic differences, with urban children having higher antibody titers. The findings are indicative of differential exposure rates and suggest that actual cases of leptospirosis may be present, yet undiagnosed.

Antibodies, Bacterial↗