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A Stang

Publications and source records attributed to A Stang.

At least 37 records · Page 2Linked to original sources
PubMed2001

Medical risk factors for small-bowel adenocarcinoma with focus on Crohn disease: a European population-based case-control study.

BACKGROUND: Crohn disease and biliary diseases have been associated with small-bowel adenocarcinoma (SBA). We examined how medical conditions affect the risk of SBA. METHODS: A population-based European multicentre case-control study during the period 1995-97 including 95 histologically verified cases of SBA along with 3335 population controls; 70 cases (74%) and 2070 (62%) controls were interviewed about previous medical conditions. RESULTS: Crohn disease was identified in two SBA cases (both located in ileum) and two controls; odds ratio (OR) 53.6 (6.0-477) (95% CI in parentheses). Only one case and no controls had had long-standing Crohn disease. Coeliac disease was associated with SBA (2 cases, 0 controls), but one of the cases was diagnosed at the same time as the SBA. Overall, people with a history of gallstones had no increased risk of SBA. The OR was exclusively increased during the 3-year period preceding the SBA diagnosis. Previous gallstone surgery, which may be a sign of severe gallstone disease, was not associated with SBA. Liver cirrhosis, hepatitis or medical treatments with radioactive substances or corticosteroid tablets were not associated with this disease. Cases with SBA had an increased prevalence of anaemia; OR 15.3 (2.5-92.1). An association between low educational level and SBA was found; OR 1.75 (1.0-3.0). CONCLUSION: This study supports Crohn disease and coeliac disease being strong but rare risk factors for SBA. Previous gallstones were unrelated to SBA, and detection bias may account for the findings in earlier studies.

Adenocarcinoma↗
PubMed2001

Undescended testis and the risk of testicular cancer: importance of source and classification of exposure information.

BACKGROUND: The strength of the association between undescended testis and testicular cancer varies considerably across studies. Here we report the effect of various classifications of self-reported history of undescended testis and different data sources on the estimates of the risk of testicular cancer from a case-control study. METHODS: We performed a population-based case-control study including 269 testicular cancer cases and 797 controls matched on age and region. Medical history was assessed by interviews (index persons) and mailed questionnaires (mothers). We used conditional logistic regression to calculate odds ratios (OR) and kappa coefficients to assess agreement between different sources of information. RESULTS: Odds ratios for testicular cancer ranged between 2.4 and 5.4 based on the sons' self-reports and between 1.1 and 1.9 based on the mothers' reports. The agreement between the sons and mothers on undescended, gliding or retractile testis was fair (kappa 0.53) and was good when these conditions were treated by surgery (kappa 0.89). The rating of a history of undescended testis by two urologists was fair (kappa 0.54). CONCLUSIONS: The questionnaire design, the classifications of undescended testis and data sources have an important impact on the OR for the association of undescended testis and testicular cancer. These factors may partially explain the heterogeneity of the OR for this association in case-control studies relying on self-reports.

Adolescent↗
PubMed2001

The possible role of radiofrequency radiation in the development of uveal melanoma.

There are few epidemiologic studies dealing with electromagnetic radiation and uveal melanoma. The majority of these studies are exploratory and are based on job and industry titles only. We conducted a hospital-based and population-based case-control study of uveal melanoma and occupational exposures to different sources of electromagnetic radiation, including radiofrequency radiation. We then pooled these results. We interviewed a total of 118 female and male cases with uveal melanoma and 475 controls matching on sex, age, and study regions. Exposure to radiofrequency-transmitting devices was rated as (a) no radiofrequency radiation exposure, (b) possible exposure to mobile phones, or (c) probable/certain exposure to mobile phones. Exposures were rated independently by two of the authors who did not know case or control status. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). We found an elevated risk for exposure to radiofrequency-transmitting devices (exposure to radio sets, OR = 3.0, 95% CI = 1.4-6.3; probable/certain exposure to mobile phones, OR = 4.2, 95% CI = 1.2-14.5). Other sources of electromagnetic radiation such as high-voltage lines, electrical machines, complex electrical environments, visual display terminals, or radar units were not associated with uveal melanoma. This is the first study describing an association between radiofrequency radiation exposure and uveal melanoma. Several methodologic limitations prevent our results from providing clear evidence on the hypothesized association.

Adolescent↗
PubMed2001

Skin melanoma in Saarland: incidence, survival and mortality 1970-1996.

Over the past few decades, the incidence of cutaneous malignant melanoma has been rising in both sexes in almost all developed countries, notably those with fair-skinned populations. Detailed population-based time trend analyses of skin melanoma incidence and survival in Germany accounting for stage have not been published until now. We analysed skin melanoma data from the population-based Saarland Cancer Registry in Germany from 1970 to 1996. Incidence rates were age-standardized. We estimated 5-year disease-specific survival rates and evaluated the effects of sex, age, calendar period and staging on the prognosis in Cox's proportional hazards models. From 1970-1972 to 1994-1996, melanoma incidence increased 170% from 2.4 to 6.5 per 100 000 person-years among men and 150% from 2.4 to 6.0 per 100 000 person-years among women. Mortality rates peaked in 1988-1990. After 1988-1990, mortality rates declined among women and remained roughly constant among men. The increase in the incidence of localized melanoma and T1-T2 melanoma respectively is driving the overall incidence trend. The improvement of survival over time is most likely due to earlier detection of skin melanoma. In the 1990s, about 30% of all newly diagnosed skin melanoma had stage T3 or T4, implying that further improvement in survival by earlier detection is feasible.

Adult↗
PubMed2000

[Risk factors and surgery rates in gallstones. Results of a population-based study].

STUDY OBJECTIVE: The prevalence of gallstone disease, time trends in the frequency of cholecystectomies and risk factors for the occurrence of cholelithiasis were examined in a cross-sectional population study. METHODS: The survey was based on a random sample from the populations of 4 regions in Germany, stratified by region, age and sex. Information on the frequency of gallstone disease and on potential risk factors were collected by standardized interviews. For the statistical analysis, multiple logistic regression was used. RESULTS: Overall, 1,085 persons were interviewed. The age-standardized prevalence of known gallstones was 4.2% for men and 14.5% for women. The frequency of cholecystectomy almost tripled in women from 1985 to 1994 as compared to 1975 to 1984 despite a decreasing trend in gallstone diagnoses in the same time period. No such trend was apparent in men. In men, age, body weight, changes in body weight, diabetes and use of corticosteroids were identified as risk factors for gallstone disease. In women, gallstone disease was also associated with body weight, changes in body weight and age, and, in addition, the number of births. An inverse association with gallstone disease was found for use of oral contraceptives and level of education in women.

Adolescent↗
PubMed2000

Molecular and functional diversity of neural connexins in the retina.

Electrical synapses (gap junctions) in neuronal circuits have become a major focus in the study of network properties such as synchronization and oscillation (Galarreta and Hestrin, 1999; Gibson et al., 1999). Despite the recent progress made in unraveling the contribution of gap junctions to network behavior, little is known about the molecular composition of the junctional constituents. By cloning gap junction proteins [connexins (Cxs)] from zebrafish retina and through functional expression, we demonstrate that the retina possesses a high degree of connexin diversity, which may account for differential functional properties of electrical synapses. Three new Cxs, designated as zebrafish Cx27.5 (zfCx27.5), zfCx44.1, and zfCx55.5, and the carp ortholog of mammalian Cx43 were cloned. By in situ hybridization and in situ RT-PCR, we demonstrate that the four fish connexin mRNAs show differential localization in the retina. Transient functional expression in paired Xenopus oocytes and in the neuroblastoma N2A cell line indicate an extreme range of electrophysiological properties of these connexins in terms of voltage dependence and unitary conductance. For instance, the new zfCx44.1 exhibited high sensitivity to voltage-induced closure with currents decaying rapidly for transjunctional potentials >10 mV, whereas zfCx55.5 channels showed an opposite voltage dependence in response to voltage steps of either polarity. Moreover, although zfCx44.1 channels showed unitary conductance as high as any previously reported for junctional channels (nearly 300 pS), zfCx55. 5 and zfCx27.5 exhibited much lower unitary conductances (<60 pS).

Animals↗
PubMed2000

The prognostic value of cyclin D1, p53, and MDM2 protein expression in uveal melanoma.

Malignant uveal melanoma is the commonest primary intraocular tumour in adults. It metastasizes frequently and 50% of patients die within 10 years of diagnosis. The expression of cyclin D1, p53, and MDM2 in uveal melanoma and their relationship to metastasis-free 5-year survival was determined, in order to investigate whether these proteins help to distinguish those patients with a favourable prognosis from those with a poorer one. Ninety-six eyes enucleated for uveal melanomas were immunohistochemically analysed for the protein expression of cyclin D1 and related cell-cycle markers, p53 and MDM2. The evaluation of the specimens was undertaken by two independent pathologists without knowledge of the outcome. Statistical analysis of clinical, morphological, and immunohistological features was performed. A 'favourable outcome' was defined as survival of at least 5 years after diagnosis, without metastases (n=57). An 'unfavourable outcome' was defined as death from metastases within the first 5 years after diagnosis of uveal melanoma (n=39). Cyclin D1 positivity (>15% positive tumour cells) as well as p53 positivity (>15% positive tumour cells) was associated with an unfavourable outcome (for cyclin D1: odds ratio=4. 2, 95% confidence interval 1.5-11.8, p=0.006; for p53: odds ratio=3. 2, 95% confidence interval 1.1-9.3, p=0.03). In addition, cyclin D1 positivity was associated with the presence of extraocular extension of the tumour (p=0.01), with the mixed or epithelioid cell type (p=0. 02), and with the tumour cell MIB-1 positivity (p=0.0001). MDM2 immunoreactivity of the tumour cells showed a potential correlation with clinical outcome (odds ratio=2.1, 95% confidence interval 0.8-5. 8, p=0.13). Multiple logistic regression models showed that cyclin D1 positivity is an independent prognostic factor after control for other prognostic markers. The expression of cyclin D1 in uveal melanoma is associated with a more aggressive course and histologically unfavourable disease. This could serve as a further independent prognostic factor in uveal melanoma.

Adolescent↗
PubMed2000

Is there an association between alcohol intake or smoking and small bowel adenocarcinoma? Results from a European multi-center case-control study.

OBJECTIVE: To discover whether tobacco smoking and intake of different types of alcoholic drinks are associated with small bowel adenocarcinoma (SBA). METHODS: A population-based European multi-center case-control study was conducted from 1995 to 1997. RESULTS: After a histological review using uniform diagnostic criteria, 47 (33%) of the 142 identified cases of SBA were excluded due to reclassification as either tumors of the papilla of Vater (n = 22), stromal tumors, or metastases; 95 cases were accepted for study. In all, 70 cases of SBA together with 2070 controls matched by age, sex, and region were interviewed. A high intake (more than 24 g alcohol per day) of beer or spirits was associated with SBA, an odds ratio (OR) of 3.5 and 95% confidence intervals (CI) of 1.5-8.0 and 3.4 (95% CI 1.3-9.2), respectively). There was no association with wine intake or total alcohol intake. Tobacco smoking was probably unrelated to SBA. CONCLUSIONS: A high intake of beer or spirits seems to be a risk factor for SBA. Since this association was not seen for wine drinkers, protective components of wine may counterbalance a carcinogenic effect of alcohol on the small bowel. Alternatively, the result may be confounded by other factors, e.g. dietary factors.

Adenocarcinoma↗
PubMed2000

Occupation and small bowel adenocarcinoma: a European case-control study.

OBJECTIVES: Because of the rarity of small bowel adenocarcinoma (SBA), little is known about the aetiology of this disease. This study aimed to identify occupational clustering of cases SBA as a systematic approach to new hypotheses on the aetiology of this disease. METHODS: A European multicentre case-control study was conducted in 1995-7, inclusive. Incident cases aged 35-69 years with SBA (n=168) were recruited before acceptance by a pathologist. Altogether 107 cases and 3915 controls were accepted, of which 79 cases, 579 colon cancer controls, and 2070 population controls were interviewed. RESULTS: The strongest industrial risk factors for SBA taking account of 10 years' exposure lag were dry cleaning, manufacture of workwear, mixed farming (women), and manufacture of motor vehicles (men). A significantly increased risk of SBA (odds ratio (OR) and 95% confidence interval (95% CI)) was found among men employed as building caretakers, OR 6.7 (1.7 to 26.0) and women employed as housekeepers, OR 2.2 (1.1 to 4.9); general farm labourers, OR 4.7 (1.8 to 12.2); dockers, OR 2.9 (1.0 to 8.2); dry cleaners or launderers, OR 4.1 (1.2 to 13.6); and textile workers (sewers or embroiderers), OR 2.6 (1.0 to 6.8). For the last four groups, together with welders OR 2.7 (1.1 to 6.6) (men) an exposure-response pattern was found when calculating the ORs for jobs held 1-5 years and >5 years, with never having held the job as reference. The ORs (95% CIs) for 1-5 years and >5 years were 4.3 (0.4 to 44.0) and 3.5 (0.9 to 13.7), 3.0 (0.3 to 26.2) and 4.3 (0.9 to 21.2), 4.6 (0.4 to 48.1) and 11.0 (2.0 to 60.4), 1.3 (0.2 to 11.0) and 5.8 (2.0 to 17.2), and 2.8 (0.3 to 23.8) and 4.6 (1.3 to 16.6), respectively, for each of these occupations. Among welders, people performing semiautomatic arc welding (MIG/MAG) were identified as a high risk group (OR 5.0 (1.3 to 19.6)). CONCLUSIONS: This explorative study suggests an increased occurrence of SBA in certain occupations, which needs further evaluation.

Adenocarcinoma↗
PubMed2000

Expression of the cell adhesion molecules ICAM-1, VCAM-1 and NCAM in uveal melanoma: a clinicopathological study.

To investigate the relationship between the expression of the cell adhesion molecules intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and neural cell adhesion molecule (NCAM) in uveal melanoma and the metastatic spread in the first 5 years after diagnosis, we performed a hospital-based case-control study with human tissue from 90 patients who underwent enucleation for primary uveal melanoma (iris melanoma excluded). Thirty-five patients developed metastasis within the first 5 years, and 55 patients lived metastasis-free for at least 5 years after enucleation. The paraffin-embedded and formalin-fixed globes were studied by immunohistochemistry with monoclonal antibodies for ICAM-1, VCAM-1 and NCAM. A strong ICAM-1 positivity (more than 75% of the tumor cells stained positive) was detected in 73 tumors (81%). The expression of 75% or less ICAM-1 positive cells in tumors was strongly associated with the development of metastases (odds ratio: 7.5, p = 0.001). Multiple logistic regression models showed that ICAM-1 is an independent risk factor for metastasis even after control for important prognostic markers like extraocular growth, ciliary body involvement, scleral infiltration and cell type. VCAM-1 was expressed in 24 out of 88 tumors (27.3%) and NCAM only in 14 out of 87 tumors (16%). Only spindle cells stained positive with anti-NCAM. NCAM and VCAM-1 expression was not related to metastasis. Our results show that the loss of ICAM-1 expression is associated with an increased risk of metastasis within the first 5 years after diagnosis.

Adult↗
PubMed2000

New contraceptive eligibility checklists for provision of combined oral contraceptives and depot-medroxyprogesterone acetate in community-based programmes.

Community-based services (CBS) have long used checklists to determine eligibility for contraceptive method use, in particular for combined oral contraceptives (COCs) and the 3-month injectable contraceptive depot-medroxyprogesterone acetate (DMPA). As safety information changes, however, checklists can quickly become outdated. Inconsistent checklists and eligibility criteria often cause uneven access to contraceptives. In 1996, WHO produced updated eligibility criteria for the use of all contraceptive methods. Based on these criteria, new checklists for COCs and DMPA were developed. This article describes the new checklists and their development. Several rounds of expert review produced checklists that were correct, comprehensible and consistent with the eligibility requirements. Nevertheless, field-testing of the checklists revealed that approximately half (48%) of the respondents felt that one or more questions still needed greater comprehensibility. These findings indicated the need for a checklist guide. In March 2000, WHO convened a meeting of experts to review the medical eligibility criteria for contraceptive use. The article reflects also the resulting updated checklist.

Community Health Services↗
PubMed2000

Sorting the hype from the facts in testicular cancer: is testicular cancer related to trauma?

PURPOSE: The rate of testicular cancer is increasing. Trauma severe enough to cause testicular atrophy is a putative risk factor for testicular cancer but the epidemiological evidence is not conclusive. A population based, multicenter case-control study was performed from 1995 to 1997 to investigate potential risk factors for gonadal and extragonadal germ cell cancer. MATERIALS AND METHODS: The study was done in 5 German regions. Interviews were performed with 269 eligible male patients with a histologically verified diagnosis and 797 controls. Detailed information on medical and family history was collected at personal interviews. RESULTS: We identified a significantly elevated risk for testicular cancer in relation to testis and/or groin trauma (odds ratio 2.5, 95% confidence interval [CI] 1.51 to 4.20). After introducing a lag time by excluding reports of trauma within the last 12 months before diagnosis or interview the corresponding odds ratio was 2.1 (95% CI 1.24 to 3.61). Analysis of the circumstances and the reported types of injury allowed us to restrict the study to testis trauma specifically, which had an odds ratio of 3.49 (95% CI 1.78 to 6.81). To account for a potential reporting bias analysis was restricted to traumatic episodes for which medical attention was sought. This restriction resulted in an odds ratio of 0.70 (95% CI 0.19 to 2.63) after excluding from study trauma reports within the last 12 months. CONCLUSIONS: The results of our study do not support the hypothesis that testicular trauma is an important risk factor for testicular cancer. The possibility of recall bias should be considered.

Adolescent↗
PubMed1999

Perspectives of clinical epidemiology in Germany.

The aim of this article is to discuss the perspective of clinical epidemiology in Germany. The following statements are discussed: (1) There is some confusion about the definition of clinical epidemiology. (2) There is a latent and growing need for clinical epidemiology in Germany. (3) Clinical epidemiology is an interdisciplinary field and not simply clinical medicine, epidemiology, biometry, or medical informatics. (4) We must continue with the education of clinicians and nonclinical methodologists in clinical epidemiology to develop the field of clinical epidemiology in Germany, Biometry, medical informatics, and epidemiology will play an essential role for this purpose. (5) The German scientific community urgently needs clinicians and scientists with experience in methodological research to specialize in the methods of clinical epidemiology. (6) The starting point for the development of clinical epidemiology in Germany, clear deficits in the past notwithstanding, is promising. However, we will only be able to develop the field if the egoism of the different disciplines can be tamed.

Biometry↗
PubMed1999

Cancer occurrence in the elderly: agreement between three major data sources.

PURPOSE: To explore agreement on cancer occurrence and site among Medicare Part A, Massachusetts Cancer Registry, and death certificates. METHODS: We linked these data sources with the cohort of the population-based East Boston Senior Health Project, a component of the National Institute on Aging's Established Populations for Epidemiologic Studies of the Elderly. The cohort consists of 905 subjects dying between January 1986 and December 1990. RESULTS: We detected the following agreements on cancer occurrence: hospitalization data and death certificates (kappa = 0.70), hospitalization and cancer registry data (kappa = 0.59), and cancer registry and death certificate data (kappa = 0.50). Measures of agreement changed little when the analyses were stratified by age, sex, calendar year and place of death, autopsy performance, cigarette smoking or alcohol consumption. Site-specific agreements were higher for colorectal and respiratory tract cancer compared to breast and prostate across all three comparisons. CONCLUSIONS: The results should assist epidemiologists to better understand the strengths and limitations of these data sources.

Aged↗
PubMed1999

Descriptive epidemiology of small intestinal malignancies: the German Cancer Registry experience.

In the first population-based analysis of certain epidemiologic features of primary malignancies of the small intestine in Germany, we used data from the Saarland Cancer Registry (1982-1993) and from the former National Cancer Registry of the German Democratic Republic (1976-1989). The age-standardized incidence rates for ages 0-74 years is 3.3-6.2 per million per year. The average incidence rates of the federal state Saarland are for men about 1.3 times and for women about 1.4 times the rate of the former German Democratic Republic. After the age of 30 years, the incidence rates increased with increasing age. Incidence rates for carcinoids levelled off after the age of 54 years. Rates for men were 35-40% higher than for women after adjusting for age. The risk for carcinomas, malignant carcinoids and malignant lymphoma were higher for men than for women.

Adolescent↗