PubMed Health⌕ Search

Biomedical subjects

A Eberle

Publications and source records attributed to A Eberle.

At least 19 recordsLinked to original sources

[Malignant melanoma of the skin as evidenced by epidemiological cancer registries in Germany -- incidence, clinical parameters, variations in recording].

PURPOSE: To exclude bias of registration evidenced by relevant differences among German cancer registries in the incidence of malignant melanoma (melanocarcinoma). METHODS: Cancer registries in the Federal German states of Hamburg, Schleswig-Holstein, Bremen, Rhineland-Palatinate, Saarland, the Munich District and the County of Münster featured registration data of malignant melanoma diagnosed in 2000 A. D. Figures and incidence rates, distribution of T-stage of the primary tumour were analysed as well as the distribution of sources reporting melanoma to the registries. Details of outpatient treatment of cutaneous melanoma by dermatologists in private practice were investigated. RESULTS: Data of 2,471 malignant melanoma cases were analysed. The highest age standardised incidence rates were 15.7 per 100,000 women and 19 per 100,000 men while the lowest rates were reported as 7.8 and 6.6 per 100,000, respectively (European standard). The proportion of stage T1 tumours varied between 21.5 and 59.2 %. We observed remarkable variations in the structure of reporting sources among the registries. The proportion of reports from dermatologists in private practice varied between 2.2 and 62 %, with higher proportions associated with more T1-T2 tumours but also lower completeness of stage reports. No clear association was identified between incidence of melanoma and reporting sources. CONCLUSION: Malignant melanomas of smaller size (T1-T2) are reported more frequently in an outpatient setting but very often without data. Hospital departments of dermatology contribute high-quality data with better completeness especially for later stage melanomas. Desirable inclusion of notifications from nationwide operating dermatopathology laboratories is complicated by the Federal German structure of cancer registration. Especially in case of malignant melanoma of the skin notification reports from all sectors of the health care system are imperative for valid epidemiological results.

Cohort Studies↗

On the association between valproate and polycystic ovary syndrome.

Recent studies by Isojärvi et al. have raised the issue of an increased incidence of polycystic ovary syndrome (PCOS) in women with epilepsy treated with valproate (VPA) and have proposed replacement with lamotrigine (LTG). Polycystic ovaries (PCO) are a common finding, with a prevalence >20% in the general population, and are easily detected by pelvic or vaginal ultrasonography, whereas PCOS is comparatively rare: few women with PCO have fully developed PCOS, which includes hirsutism, acne, obesity, hypofertility. hyperandrogenemia, and menstrual disorders. From an extensive review of the current literature, it appears that there are no reliable data on the actual prevalence of PCOS in normal women and in women with epilepsy. The pathogenesis of PCO is multifactorial, including genetic predisposition and the intervention of environmental factors, among which weight gain and hyperinsulinism with insulin resistance may play a part. The roles of central (hypothalamic/pituitary), peripheral, and local ovarian factors are still debated. PCO and PCOS appear to be more frequent in women with epilepsy, but there are no reliable data showing a greater prevalence after VPA. The recent studies by Isojärvi et al. may have been biased by the retrospective selection of patients. To date, there is no reason to contraindicate the use of VPA in women with epilepsy. However, patients should be informed about the risk of weight gain and its consequences.

Adolescent↗

Gender differences in carpal tunnel syndrome? occupational and non-occupational risk factors in a population-based case-control study.

PURPOSE: To determine the role of occupational and personal risk factors of carpal tunnel syndrome (CTS) separately in men and women.METHODS: Men (n = 404) and women (n = 404) younger than 65 years with first surgery for CTS in 1995/96 were sampled at random from the Bremen population (0.65 million) and matched to controls by age and gender sampled from the population registry. A self-administered questionnaire with 77 questions inquired about personal factors and activities during work and private environment (response: 60% of eligible cases and 52% in controls, respectively).RESULTS: CTS risk increased with body mass index (BMI): odds ratio for each unit of BMI [kg/m(2)] OR(men) = 1.13; (95%-confidence-limits CL(men) 1.06, 1.20), OR(women) = 1.09 (CL(women) 1.04, 1.14). Multivariate analysis adjusting for BMI showed more pronounced risks in men compared with women for repetitive movements of the hand: OR(m) = 2.89 (CL 1.82, 4.58); OR(w) = 2.10 (CL 1.37, 3.22), for forceful grip: OR(m) = 2.69 (CL 1.70, 4.27); OR(w) = 2.29 (CL 1.43, 3.66), but not for household chores: OR(m) = 0.64 (CL 0.40, 1.03); OR(w) = 0.88 (CL 0.34, 2.29). Women worked less hours per week than men but manual exposures remained more relevant in men after adjustment. Exposure-response-relationships could be demonstrated for all work related exposures. Women were at higher risk for CTS if they had had more than two births or a history of hysterectomy. Adding these factors to the logistic model still showed an association between manual work and CTS. Blinded expert rating (manual vs. non-manual) of jobs held by respondents and non-respondents and by cases and controls did not reveal relevant selection effects or recall-bias.CONCLUSIONS: CTS is a work related disease in both men and women, the fraction attributable to work in the Bremen population under age 65 is estimated to be 33% in men and 15% in women. Funding: German Federal Ministry for Education & Research: 01 EG 9512.

Journal Article↗

Elecsys CEA, PSA and AFP. Clinical results of a multicentre evaluation.

Three tumormarker assays, Elecsys CEA, PSA and AFP, have been evaluated in an international multicentre study to characterize their clinical performance and to verify the comparability with the corresponding tests of the Enzymun-Test product line and other methods. For each of the markers results were obtained from four laboratories. On the basis of 314 and 199 specimens respectively, (preliminary) reference ranges could be established for CEA and PSA. For the prostate marker, the age dependence of the antigen level could be clearly confirmed. Mean concentrations range between 0.51 ng/ml (< 40 years) and 3.57 ng/ml (> 70 years). Referring to CEA, 95th percentiles of 4.31 ng/ml and 2.69 ng/ml were elaborated for smokers and nonsmokers. In general, good to excellent correlations (r > 0.98) were found between the Elecsys and Enzymun-Tests. Regarding the systematic comparability of both systems, most of the slopes derived from the individual method comparison studies are within the +/- 10% range of the respective standardization results. The specific distribution pattern of the individual tumormarker values elaborated with sample material of known clinical background, reflects the well established categorization of different benign and malignant diseases according to their characteristic marker levels. Of utmost importance, however, is the excellent comparability of the Elecsys assays with the corresponding Enzymun-Tests and the FDA approved AIA 1200 tests from TOSOH in follow-up studies. Almost superimposable concentration curves guarantee that identical diagnostic information is derived from all three methods. Especially for PSA, a series of measurements on sera of prostatectomized patients proved the usability and clinical value of the test also for this particular indication. For either one of the Elecsys tests, the feasibility of using plasma as sample material was verified.

Adult↗

Prevalence of mutations in the insulin receptor gene in subjects with features of the type A syndrome of insulin resistance.

Mutations of the insulin receptor gene are a cause of the type A syndrome of extreme insulin resistance. This study assessed the prevalence of such mutations in women with clinical features of the type A syndrome including ovarian hyperandrogenism, moderate-to-severe degrees of insulin resistance, and acanthosis nigricans. We studied 22 unrelated women with insulin resistance (fasting insulin > 300 pM [50 microU/ml] and/or peak during an oral glucose tolerance test (OGTT) > 1,800 pM [300 microU/ml]), acanthosis nigricans, and the polycystic ovary syndrome (hyperandrogenemia, oligoamenorrhea, and hirsutism). Two insulin-resistant probands with congenital generalized lipodystrophy and one male proband with severe insulin resistance also were included in the study. Southern blotting experiments were performed to exclude gross gene deletions, insertions, or rearrangements. Exons 2-22 of the insulin receptor gene were polymerase chain reaction (PCR) amplified from genomic DNA and screened for nucleotide variation using single-strand conformation polymorphism (SSCP). No nucleotide variation between study subjects was detected in exons 4-6, 10-12, 15, 16, 18, 19, or 21. Sequencing of amplified DNA revealed that SSCP variants in exons 2, 3, 8, 9, and 17 corresponded to known silent polymorphisms within the coding region. Variants in exons 2, 9, 13, and 14 were caused by novel silent polymorphisms; variants in exons 7 and 22 were caused by nucleotide substitutions in flanking introns. One proband was found to have a heterozygous point mutation in exon 20 (CGG-->CAG, Arg1174-->Gln) that involves the intracellular receptor beta-subunit.(ABSTRACT TRUNCATED AT 250 WORDS)

Acanthosis Nigricans↗

A physiological role for cholecystokinin as a regulator of gastrin secretion.

To explore the role of cholecystokinin (CCK) in regulating gastrin secretion in humans, the effect of a CCK antagonist (loxiglumide) on meal-stimulated hormone responses was investigated. Subjects received 500 mL of a liquid test meal in the presence and absence of loxiglumide (22 mumol.kg-1.h-1). In the control experiments, both plasma gastrin and CCK levels increased postprandially. In loxiglumide-treated subjects there was a marked elevation in gastrin (area under the curve, 11,042 +/- 1493/120 min vs. 2156 +/- 281 pg/120 min) and CCK levels compared with the control experiment. These observations were confirmed in experiments with modified sham feeding and gastrin-releasing peptide stimulation in which loxiglumide pretreatment also caused a significant increase in gastrin release compared with saline (P less than 0.05). Further studies with intravenous infusion of gastrin, CCK-8, and CCK-33 with and without loxiglumide showed that the increases in CCK and gastrin during loxiglumide application cannot be explained by alterations in clearance rates. The findings of this study show that postprandial gastrin secretion is influenced by CCK and support the concept of a negative feedback control of gastrin secretion by CCK.

Adult↗

The atp operon: nucleotide sequence of the genes for the gamma, beta, and epsilon subunits of Escherichia coli ATP synthase.

The nucleotide sequence of the promoter distal region of the atp (or unc) operon of Escherichia coli has been determined. It encodes the gamma, beta and epsilon subunits of the ATP-synthase complex and includes a noncoding sequence in which transcription of the operon probably terminates. This work completes the nucleotide sequence of the operon which contains nine genes: eight encode structural proteins of the ATP-synthase complex; a ninth, the first in the operon, may be a pilot for assembly. The genes for the alpha and beta subunits have evolved from a common ancestor.

ATP Synthetase Complexes↗

Diurnal variation in the release of alpha-MSH from rat hypothalamus and pituitary.

Release of alpha-MSH from rat hypothalamic slices was characterized with respect to ionic requirements and possible diurnal variations using a sensitive radioimmunoassay. Addition of 47 mM KCl to the superfusion medium resulted in a twofold increase in alpha-MSH functions as a neurotransmitter or neuromodulator in the hypothalamus. Both spontaneous and potassium-induced alpha-MSH release compared to spontaneous release. Removal of calcium from the superfusion medium abolished the potassium-evoked release of alpha-MSH. This supports the concept that alpha-MSH release were related to diurnal variation. Marked release from the slices was observed at 10.10 h, corresponding to a peak in the alpha-MSH concentration in the hypothalamus [18] and to a lower levels of alpha-MSH in the blood. Contrarily, no significant release from the hypothalamus was obtained at 17.00 h when hypothalamic alpha-MSH content was low, but blood levels exhibited a peak. These findings suggest that there are differences in the regulation of the alpha-MSH from the pituitary and that in the hypothalamus.

Animals↗

Mechanism of alpha-melanotropin action.

A structure-function study of alpha-melanotropin has shown that this tridecapeptide consists of two message sequences, (-Glu)-His-Phe-Arg-Trp- and -Gly-Lys-Pro-Val-NH2, and a potentiator sequence, Ac.Ser-Tyr-Ser-Met-(Glu-), when acting on its melanophore receptors. The key elements of the message, -Phe-Arg- and -Lys-Pro-, do not correspond exactly to those responsible for eliciting the effect in other tissues. It appears that alpha-MSH contains more information than would be necessary to interact with only one complementary receptor site; therefore, the topography of the hormone exposed to the binding site may be different on contact with the receptors of different target cells. To further investigate this aspect, new methods for the isolation and characterization of functional receptors must be developed. We are investigating the use of chemically well-defined, biologically active, covalent hormone-macromolecule complexes for this purpose. Another approach utilizes model receptors with a recognition pattern similar to that of the biological receptor, as described in this communication for certain highly specific antibodies.

Amino Acid Sequence↗