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Biomedical subjects

L Raymond

Publications and source records attributed to L Raymond.

At least 37 records · Page 2Linked to original sources

A recombinant Chlamydia trachomatis major outer membrane protein binds to heparan sulfate receptors on epithelial cells.

Chlamydial attachment to columnar conjunctival or urogenital epithelial cells is an initial and critical step in the pathogenesis of chlamydial mucosal infections. The chlamydial major outer membrane protein (MOMP) has been implicated as a putative chlamydial cytoadhesin; however, direct evidence supporting this hypothesis has not been reported. The function of MOMP as a cytoadhesin was directly investigated by expressing the protein as a fusion with the Escherichia coli maltose binding protein (MBP-MOMP) and studying its interaction with human epithelial cells. The recombinant MBP-MOMP bound specifically to HeLa cells at 4 degrees C but was not internalized after shifting the temperature to 37 degrees C. The MBP-MOMP competitively inhibited the infectivity of viable chlamydiae for epithelial cells, indicating that the MOMP and intact chlamydiae bind the same host receptor. Heparan sulfate markedly reduced binding of the MBP-MOMP to cells, whereas chondroitin sulfate had no effect on binding. Enzymatic treatment of cells with heparitinase but not chondroitinase inhibited the binding of MBP-MOMP. These same treatments were also shown to reduce the infectivity of chlamydiae for epithelial cells. Mutant cell lines defective in heparan sulfate synthesis but not chondroitin sulfate synthesis showed a marked reduction in the binding of MBP-MOMP and were also less susceptible to infection by chlamydiae. Collectively, these findings provide strong evidence that the MOMP functions as a chlamydial cytoadhesin and that heparan sulfate proteoglycans are the host-cell receptors to which the MOMP binds.

ATP-Binding Cassette Transporters↗

TIMI frame count: a quantitative method of assessing coronary artery flow.

BACKGROUND: Although the Thrombolysis in Myocardial Infarction (TIMI) flow grade is valuable and widely used qualitative measure in angiographic trials, it is limited by its subjective and categorical nature. METHODS AND RESULTS: In normal patients and patients with acute myocardial infarction (MI) (TIMI 4), the number of cineframes needed for dye to reach standardized distal landmarks was counted to objectively assess an index of coronary blood flow as a continuous variable. The TIMI frame-counting method was reproducible (mean absolute difference between two injections, 4.7 +/- 3.9 frames, n=85). In 78 consecutive normal arteries, the left anterior descending coronary artery (LAD) TIMI frame count (36.2 +/- 2.6 frames) was 1.7 times longer than the mean of the right coronary artery (20.4 +/- 3.0) and circumflex counts (22.2 +/- 4.1, P < .001 for either versus LAD). Therefore, the longer LAD frame counts were corrected by dividing by 1.7 to derive the corrected TIMI frame count (CTFC). The mean CTFC in culprit arteries 90 minutes after thrombolytic administration followed a continuous unimodal distribution (there were not subpopulations of slow and fast flow) with a mean value of 39.2 +/- 20.0 frames, which improved to 31.7 +/- 12.9 frames by 18 to 36 hours (P < .001). No correlation existed between improvements in CTFCs and changes in minimum lumen diameter (r=-.05, P=.59). The mean 90-minute CTFC among nonculprit arteries (25.5 +/- 9.8) was significantly higher (flow was slower) compared with arteries with normal flow in the absence of acute MI (21.0 +/- 3.1, P < .001) but improved to that of normal arteries by 1 day after thrombolysis (21.7 +/- 7.1, P=NS). CONCLUSIONS: The CTFC is a simple, reproducible, objective and quantitative index of coronary flow that allows standardization of TIMI flow grades and facilitates comparisons of angiographic end points between trials. Disordered resistance vessel function may account in part for reductions in flow in the early hours after thrombolysis.

Blood Flow Velocity↗

Diet and cancers of the larynx and hypopharynx: the IARC multi-center study in southwestern Europe.

The main causes of cancer of the larynx and hypopharynx are smoking cigarettes and drinking alcohol. However, for these as well as for other cancers of the upper aerodigestive tract, some dietary components, mainly low consumption of fruit and vegetables, have been observed to be associated with increased cancer risk. We report results from a multicenter case-control study carried out in six regions of Europe located in northern Spain, northern Italy, Switzerland, and France. A total of 1,147 males with cancer (cases) and 3,057 population controls were interviewed on usual diet, lifelong drinking and smoking habits, and occupational history. Cancer cases had histologically verified epidermoid carcinomas. The cancers were classified in two anatomic sub-entities: the epilarynx (hypopharynx and upper part of the larynx), which enters into contact with the bolus and the air; and the endolarynx, through which air and tobacco smoke pass, but not the bolus. A previous report from this study found that alcohol drinking presents a greater risk factor for cancer of the epilarynx than for cancer of the endolarynx. The main results regarding diet indicate that high intake of fruit, vegetables, vegetable oil, fish, and low intake of butter and preserved meats were associated with reduced risk of both epilaryngeal and endolaryngeal cancers, after adjustment for alcohol, tobacco, socioeconomic status, and non-alcohol energy intake. Among nutrients, a reduced risk was found for high intake of vitamins C and E and for a high polyunsaturated/saturated fatty acids (P/S) ratio. While these variables are relevant in scoring nutritional behaviour, it remains unresolved whether the biologic properties of these nutrients play a role in the apparent protective effect.

Alcohol Drinking↗

[Risk factors in self-injurious behavior in a Swiss prison].

Suicide is reported to be one of the leading causes of death in prison (25-45% of deaths), and attempted suicide is observed more frequently in prison than in the general population. The purpose of this study is to identify the risk factors of the suicidal gestures (including wrist slashing) in the Geneva prison, and their impact; with a view to elaborating possible preventive measures. A case-control study (172 cases and 169 controls) was conducted retrospectively on the basis of medical records. Demographic and medical data for cases were compared to similar data for non-suicidal inmates. A multivariate analysis of the data revealed that the risk of suicidal inmates. A multivariate analysis of the data revealed that the risk of suicidal gestures increased for the following characteristics: age less than 25 years (RR = 4.4), previous suicide attempts (RR = 4.7), a past history of psychiatric treatment (RR = 2.5), and finally, opiate drug dependence (RR = 2.8).

Adolescent↗

Na+/Ca2+ exchanger in epithelial cells of the porcine cortical thick ascending limb.

Intracellular Ca2+ concentration ([Ca2+]i) plays an important role in the signal transduction processes within cortical thick ascending limb (CTAL) cells. Control of [Ca2+]i was investigated in isolated CTAL cells with microfluorescent techniques. CTAL cells pretreated with ouabain to elevate intracellular Na+ concentration ([Na+]i) had basal [Ca2+]i of 86 +/- 2 nM. Removal of extracellular Na (Nao+) or voltage depolarization with KCl (in the presence of Nao+) resulted in a rapid and reversible maximal elevation of [Ca2+]i (1,023 +/- 72 nM, n = 28), which was dependent on the presence of external Ca2+ (Cao2+). The rise in [Ca2+]i was inhibited with La3+, Mg2+, amiloride, and bepridil. The increments of [Ca2+]i with either removal of Nao+ or voltage depolarization were dependent on pretreatment with ouabain and increases in [Na+]i. The presence of a Na+/Ca2+ exchanger was, confirmed with hybridization techniques, and the isoform was identified by sequencing the alternative splicing site within the intracellular loop. A gene transcript that encodes a portion of the intracellular loop of the renal Na+/Ca2+ exchanger was amplified from cortical tissue and single CTAL cells by reverse transcription-polymerase chain reaction, using primers flanking the alternative splicing site. Southern hybridization and DNA sequencing demonstrated the isoform contained exons B and D, which is characteristic of one isoform (NACA3) of the renal Na+/Ca2+ exchanger. The results provide both functional and molecular evidence for a Na+/Ca2+ exchanger in thick ascending limb cells of the porcine kidney.

Animals↗

Recent trends in incidence of cervical cancer in several regions of south-western Europe.

In recent decades, most Western countries have experienced a decline in the incidence of invasive cervical cancer. More recently, a reversal of this trend has been noted in young women, especially in anglo-saxon countries. These trends have been attributed to the beneficial results of cervical cancer screening on the one hand, to the widespread increase of high risk sexual behaviors on the other. Recent trends in Latin European countries have not previously been studied. Time trends of incidence data from 10 regions of South-Western Europe (Geneva, Vaud, Calvados, Doubs, Bas-Rhin, Isère, Ragusa, Varese, Zaragoza and Navarra) were analysed by means of log-linear models. The data were provided for various periods of time between 1970 and 1990. The mean incidence rate varies threefold between Navarra where rates are the lowest to Calvados where they are the highest. The overall decrease rate is of the order of -3% per year but rate changes differ by age group. The reduction seems to concern mostly middle aged women. A definite trend could not be determined among younger women due to low case numbers. Thus, the hypothesis of a rising incidence in young women cannot be confirmed at this time.

Adolescent↗

Estimating the incidence of cancers in Switzerland: 1983-1987.

Estimates have recently been made of the incidence of cancers in the countries of the European Community. Similar estimates are given for Switzerland, based on data from the six Swiss cantonal cancer registries, all of which have been operating for at least 12 years. These registries cover Basel, Geneva, Neuchatel, St Gall and Appenzell, Vaud and Zurich, which account for about 50% of the Swiss population as a whole. Two different methods were used to extrapolate from the incidences observed in the regions covered by cancer registration to the entire country. The first method is based solely on the distribution of populations according to the country's main linguistic groups, whereas the second relies on mortality data. Estimates obtained by the second approach are presented and their reliability is discussed. Comparison of the age incidence curve with that of Denmark tends to confirm the validity of the estimations. Estimated standardised rates (world population) for all sites except nonmelanomatous skin cancer are 294.3 for males and 214.2 for females. Comparisons with other European countries show that in males, lung cancer is relatively less common in Switzerland, whereas in females, breast cancer is relatively more frequent.

Adolescent↗

[Psychiatric diagnosis and cause of death in a hospitalized population].

Psychosomatic theories suggest that psychiatric pathology modulates mortality rates; some diagnoses could be considered as risk factors and others as protective factors regarding the different causes of death. The results obtained so far are controversial. The present study aimed at determining the associations between psychiatric diagnosis and cause of death on the basis of 1698 deaths which occurred in a regional Swiss psychiatric hospital during the 1945-1989 period. The diagnoses were divided into four groups (psycho-organic syndromes/dysthymia/schizophrenia/others) and the causes of death into five groups (cardiovascular/lung diseases/cancer/suicide/others). As data were lacking for the entire group of hospitalized patients, associations were analyzed by way of a proportional approach (PMR). The proportional variation factors attributed to a given cause were studied by logistic regression (case-control design). The results mainly reveal the specificity of dysthymic patients which were characterized by a decreasing proportion of deaths due to pulmonary diseases and an increasing proportion of deaths due to cardio-vascular disease. Suicide was proportionally more frequent in both dysthymic and schizophrenic patients. The classic hypothesis that schizophrenics are protected against cancer was not confirmed. The limits of the proportional approach (PMR) are discussed.

Aged↗

[Multiple tumors of colon and rectum].

The possible occurrence of multiple synchronous or metachronous malignant lesions in patients with carcinoma of the colon and rectum is a well known event. In this population-based study in the Geneva area from 1970 to 1986, the frequency of synchronous colorectal carcinomas was 1.1% and that of metachronous carcinomas 1%. The relative risk of metachronous colorectal carcinoma is higher than in the general population (colon after rectum 1.2, colon after colon 1.7 and rectum after rectum 1.4). A high association of adenomatous polyps with multiple colorectal carcinoma was observed. The 5-year actuarial survival in case of curative resection was 87% for metachronous carcinomas, 35% for single carcinomas and 33% for synchronous carcinomas. We conclude that complete preoperative colonoscopy, whenever possible, should be performed to screen patients with synchronous carcinomas. Finally, a lifelong follow-up of the residual colon or rectum should be planned to detect metachronous lesions.

Actuarial Analysis↗

[First treatment demands for drug abuse: and indicator of developmental trends].

The county of Geneva, Switzerland, is part of an international multi-city survey under the auspices of the Council of Europe. This survey is designed to use common indicators for assessing and comparing drug misuse and its evolution in participating cities and regions. Its aim is to improve the strategies for controlling drug misuse. The first indicator under study is the "first treatment demand". Its objectives are to evaluate the treatment demand as well as the evolution of drug misuse in terms of patient characteristics, so as to optimise prevention and treatment policies. All treatment demands for drug misuse that meet the study's entry criteria are recorded in a permanent and centralized data bank, through an anonymous encoded form filled in by the treatment centers at the time of the demand. Later demands by the same patient are merged with the precedent ones. In this way, both the totality of treatment demands and the subset of first demands can be analyzed and information about individual trajectories can be collected. The introduction of this indicator is subjected to various problems due first of all to the illicit character of drug misuse. In particular, the necessary measures to guarantee strict confidentiality make it more difficult to obtain reliable data, especially for the merging of different treatment demands by the same patient. This paper reports on the introduction of the indicator in Geneva and its anticipated results.

Confidentiality↗

Mortality and incidence of cancer among a cohort of self employed butchers from Geneva and their wives.

To investigate whether specific cancers are associated with the occupation of butcher, as has been reported from other countries, a historical prospective cohort study was undertaken. The cohort consisted of all self employed butchers (n = 552) and pork butchers (n = 310) born since 1880 who set up a shop in the canton of Geneva from 1901 to 1969, and of their wives (n = 887). The study group was followed up from 1901 to 1990 for general mortality, from 1942 to 1990 for cause specific mortality, and from 1970 to 1989 for incidence of cancer. There was no trace of 45 men (5%) and 52 women (6%). Compared with the general population of the canton of Geneva, butchers and pork butchers experienced a significant increase, taking into account 15 years of latency, in mortality from all causes (observed deaths (Obs) 540, expected deaths (Exp) 445.5, standardised mortality ratio (SMR) 121, 90% confidence interval (90% Cl) 113-130). There were significant excesses in incidence and mortality from colorectal cancer, cancer of the prostate, and all malignant neoplasms, and in incidence of cancer of the liver. The risk of lung cancer was significantly increased among pork butchers (SMR 176, 90% Cl 114-262; standardised incidence ratio (SIR) 231, 90% Cl 137-368) but not among butchers (SMR 92, 90% Cl 59-138; SIR 113, 90% Cl 67-179). There was also a significant increase in mortality from cancer of the larynx among butchers. For non-malignant causes of death significant excesses were found among all men for ischaemic heart disease, motor vehicle accidents, and cirrhosis of the liver. Analysis of subgroups showed a cluster of deaths from leukaemia among older butchers born between 1880 and 1899 (Obs 5, Exp 0.6, p < 0.0001). Exposure of pork butchers to polycyclic aromatic hydrocarbons during meat smoking, which was assessed in a contemporary study, might have contributed to their increased risk of lung cancer. The possible role of other factors, especially cigarette smoking, nitrosamines, and oncogenic viruses was discussed. Moreover, there was evidence from another contemporary study that butchers and pork butchers ate more animal fat, and probably more animal protein, than the average male population of Geneva. These results suggest that dietary factors could be implicated in the excesses of colorectal cancer, cancer of the prostate, and ischaemic heart disease. An increased risk for alcohol abuse might explain the excesses of liver cirrhosis, cancer of the liver, cancer of the larynx and motor vehicle accidents. Among all wives overall mortality was similar to that expected (SMR 100, 90% Cl 93-108) and there was no significant excess risk for any specific cancer nor for any non-malignant cause of death. Results for cancer of the cervix uteri, especially among subgroups, suggest an increased risk consistent with previous findings from other countries.

Animals↗

[Multiple tumors of the colon and rectum].

The possible occurrence of multiple synchronous or metachronous malignant lesions in patients with a carcinoma of the colon and rectum is a well known event. In this population-based study in the Geneva area from 1970 to 1986, the frequency of synchronous colorectal carcinomas was of 1.1% and that of metachronous carcinomas of 1%. The relative risk of metachronous colorectal carcinoma is higher than in the general population (colon after rectum 1.2, colon after colon 1.7 and rectum after rectum 1.4). A high association of adenomatous polyps with multiple colorectal carcinomas was observed. The 5-year actuarial survival in case of curative resection was of 87% for metachronous carcinomas, 35% for single carcinomas and 33% for synchronous carcinomas. We conclude that complete preoperative colonoscopy, whenever possible, should be performed to screen patients with synchronous carcinomas. Finally, a lifelong follow-up of the residual colon or rectum should be planned to detect metachronous lesions.

Aged↗

Increased risk for lung cancer and for cancer of the gastrointestinal tract among Geneva professional drivers.

A historical prospective cohort study of 6630 drivers from the Canton of Geneva was carried out to evaluate mortality and incidence of cancer in this occupation. The study population was all men (of all vocations) who held in 1949 a special licence for driving lorries, taxis, buses, or coaches and all new licence holders in the period 1949-61. Men born before 1900 and those with only an ordinary driving licence were excluded. According to the occupation registered on their licence, the 6630 drivers were distributed into three groups: (1) professional drivers (n = 1726), (2) non-professional drivers "more exposed" to exhaust gas and fumes (this group included occupations such as vehicle mechanic, policeman, road sweeper; n = 712), and (3) non-professional drivers "less exposed," composed of all other occupations (n = 4192). The cohort was followed up from 1949 to December 1986 and the trace of 197 men (3%) was lost. Compared with the general population of the Canton of Geneva, professional drivers experienced significant excess risks, taking into account 15 years of latency, for all causes of death (standardised mortality ratio (SMR) 115, 90% confidence interval (90% CI) 107-123) and for all malignant neoplasms (SMR 125, 90% CI 112-140; standardised incidence ratio (SIR) 128, 90% CI 115-142). Cause specific analysis showed significant excesses for lung cancer (SMR 150, 90% CI 123-181; SIR 161, 90% CI 129-198), oesophageal cancer (SMR 183, 90% CI 108-291), stomach cancer (SMR 179, 90% CI 117-263; SIR233, 90% CI 156-336), rectal cancer (SMR 258, 90% CIU 162-392; SIR 200, 90% CI 127-300), and cirrhosis of the liver (SMR 145, 90% CI 104-198). Risk of lung cancer increased significantly with time from first exposure. Among non-professional drivers no significant excess risk was found except for lung cancer mortality among the "less exposed" group (SMR 121, 90% CI 103-140), and for incidence of lung cancer among the "more exposed" group (SIR 161, 90% CI 111-227). The possible casual relation between exposure to engine exhaust emissions and the increased risk for lung cancer and for cancer of the gastrointestinal tract found among professional drivers is discussed.

Aged↗

Prevention of cutaneous melanoma: an epidemiological evaluation of the Swiss campaign.

A national information program, focusing on the main recognized risk factors (primary prevention) and on the potential benefits of early detection (secondary prevention) of cutaneous malignant melanoma, was launched in Switzerland in May 1988. The first campaign, based on a pilot study conducted in 1986 in the canton of Basel, was followed by a recall campaign in July 1989. This report describes the organization of this program and presents an assessment of its initial impact. The number of newly diagnosed cases increased more than twofold (+ 116%) in the two months following the launch of the first campaign (May to June 1988). This trend was accompanied by a statistically significant shift of case distribution towards younger ages (< 60 years; p = 0.003), and a non-significant shift was observed towards less advanced lesions (thickness < or = 1.5 mm). The incidence decreased quickly, though in the twelve month period between the two campaigns it remained 21% higher than before the inception of the program. No appreciable effects were detected from the recall campaign and no difference was seen among regions or between sexes.

Adolescent↗

The "post-Chernobyl" childhood leukemia study (ECLIS Study).

Numerous European cancer registries are working together to evaluate the current trends in the incidence of childhood leukemias after the Chernobyl accident. The study is coordinated by the International Agency for Research on Cancer. The primary objective is to establish whether the accident has resulted in an increase in the number of cases. The results will also allow an evaluation of the clusters which could be reported. According to the provisional estimations, the accident could lead to an increase of an average of 0.8% of the frequency of new cases in the European regions covered by the study. For the whole of Switzerland, this increase would correspond to 0.5 supplementary cases per year.

Accidents↗