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D Mayr

Publications and source records attributed to D Mayr.

17 recordsLinked to original sources
PubMed2006

HER-2/neu gene amplification in ovarian tumours: a comprehensive immunohistochemical and FISH analysis on tissue microarrays.

AIMS: Data on HER-2/neu overexpression, its correlation to prognosis and the success of treatment with Herceptin((R)) in ovarian carcinomas are scarce and contradictory. Therefore we assessed HER-2/neu expression and amplification in a large series of ovarian tumours by using tissue microarrays (TMAs). METHODS AND RESULTS: Two TMAs containing 173 invasive carcinomas, 36 borderline tumours, 20 granulosa cell tumours, 14 carcinosarcomas, 11 benign cystadenoms and eight other pelvic tumours were constructed to assess HER-2/neu gene amplification by fluorescence in-situ hybridization (FISH) and immunohistochemistry. Immunohistochemistry was successful in 94.3%; 81.8% were HercepTest negative, 11.3% were scored as 1+, 4.1% as 2+ and 2.8% as 3+, including 3.1% of invasive carcinomas, 2.8% of borderline tumours and 7.7% of carcinosarcomas; 83.6% could be analysed successfully by FISH revealing no aberration in 75.8%, low amplification in 2.7% and high amplification in 3.7% of the cases. In 17.8% monosomy, trisomy, polysomy or deletion could be detected. All cases with high-level amplification had 2+ or 3+ scores on immunohistochemistry. CONCLUSIONS: TMA is a feasible tool to study a large number of ovarian cases. Correlation between immunohistochemistry and FISH was excellent. HER-2/neu overexpression or gene amplification does not correlate with histological tumour type, stage, grade or prognosis.

Adolescent↗
PubMed2006

Development and characterization of monoclonal antibodies for the immunohistochemical detection of glycodelin A in decidual, endometrial and gynaecological tumour tissues.

AIMS: Glycodelin is a glycoprotein with a molecular weight of 28 kDa. Unusual LacdiNAc structures have been identified on glycodelin A, isolated from amniotic fluid. Three major functions of this glycoprotein have been identified. Glycodelin is an immunosuppressive molecule, a marker of morphological differentiation, and a contraceptive. Because no monoclonal antibodies for glycodelin A are commercially available, our aim was to develop and characterize three monoclonal antibodies against this glycoprotein. METHODS AND RESULTS: Glycodelin A was purified from amniotic fluid by three chromatographic steps and its purity was checked by SDS-PAGE. Antibodies were generated from immunized BALB/c mice. Three IgG1 monoclonal antibodies detecting glycodelin A were cloned. All three antibodies recognized carbohydrate structures of glycodelin A and did not cross-react with glycodelin S. They are applicable to immunohistochemistry (frozen and paraffin sections), ELISA and Western blots. CONCLUSION: The new antibodies can be used for the detection of glycodelin A in frozen and paraffin-embedded decidual and endometrial tissue. One antibody (A87-B/D2) can be used for the detection of glycodelin in endometrial and ovarian tumour tissues. Because glycodelin A is a major secretory endometrial product during the luteal phase, in early pregnancy and in gynaecological tumours, the new antibodies are, potentially, valuable tools for the study of endometrial development and tumour progression.

Amniotic Fluid↗
PubMed2005

[Schistosomiasis in a leiomyoma of the uterus].

This case report deals with an, in our regions, unusual diagnosis of coincidence of a genital schistosomiasis of a 30-year-old woman, coming from Africa. The female patient presented herself by a specialist because of longer lasting hypermenorrhoe. After clinical examination the patient underwent an operation because of an uterus myomatosus. The histopathological evaluation showed beside a leimyoma an expanded infestation with schistosomiasis haematobium. After pathological diagnosis the patient underwent the standard therapy with a single injection of praziquantel. We report about the clinic, epidemiology, morphology and diagnostic.

Adult↗
PubMed2004

Analysis of HER-2/neu amplification in endometrial carcinoma by chromogenic in situ hybridization. Correlation with fluorescence in situ hybridization, HER-2/neu, p53 and Ki-67 protein expression, and outcome.

Fluorescence in situ hybridization (FISH) is the most widely used technique to detect HER-2/neu gene amplification; however, it is only available in some institutions. In contrast, chromogenic in situ hybridization (CISH) can be evaluated by routine light microscopy. In endometrial carcinoma there are few data concerning HER-2/neu status and prognosis. Therefore, we determined HER-2/neu gene status by CISH using a digoxigenin-labelled probe on 60 formalin-fixed paraffin-embedded endometrial carcinomas. The data were compared with the immunohistochemistry of HER-2/neu (A0485, TAB250), p53, Ki-67, clinicopathological factors, and survival. By conventional light microscopy, HER-2/neu amplification (>/=6 copies >50% cancer cells) was detected in 14% (8/59) tumours, HER-2/neu overexpression (>10% cells moderate/strong complete membrane staining) in 22% (13/60) for A0485, and 18% (11/60) for TAB250, p53 (>10% +cells) in 61% (36/59), and Ki-67 (>50% +cells) in 50% (30/60). Discordant cases for CISH and immunohistochemistry, as well as all (2+) were further analysed by FISH (Vysis). Among 10 cases (2+) and not amplified by CISH, two showed low-level amplification by FISH. Significant correlation was found between amplification and protein overexpression (P</=0.001), and a trend with nonendometrioid type, higher grade, and older age. A better outcome (Kaplan-Meier) was observed for patients with nonamplified (1-5 copies per nucleus) or low-level (6-10 copies) amplification tumours, low Ki-67 expression, age <50 years, endometrioid type, low FIGO (International Federation of Obstetrics and Gynaecology) grade and stage, superficial myometrial infiltration, and no lymph-vascular invasion (P</=0.036), but only as a trend for HER-2/neu protein negative (P=0.13). Cox analysis revealed age, FIGO grade and stage, myometrial infiltration, and lymph-vascular invasion to be independent prognostic factors (P</=0.05), and a trend for HER-2/neu gene copy number (0.18). In endometrial carcinoma, HER-2/neu gene status can be readily assessed by CISH in routine clinical practice, and it gives more prognostic information than HER-2/neu by immunohistochemistry. FISH analysis in (2+) cases but negative by CISH may detect additional tumours with low-level amplification.

Adult↗
PubMed2003

Rapid detection of meat spoilage by measuring volatile organic compounds by using proton transfer reaction mass spectrometry.

The evolution of the microbial spoilage population for air- and vacuum-packaged meat (beef and pork) stored at 4 degrees C was investigated over 11 days. We monitored the viable counts (mesophilic total aerobic bacteria, Pseudomonas spp., Enterobacteriaceae, lactic acid bacteria, and Enterococcus spp.) by the microbiological standard technique and by measuring the emission of volatile organic compounds (VOCs) with the recently developed proton transfer reaction mass spectrometry system. Storage time, packaging type, and meat type had statistically significant (P < 0.05) effects on the development of the bacterial numbers. The concentrations of many of the measured VOCs, e.g., sulfur compounds, largely increased over the storage time. We also observed a large difference in the emissions between vacuum- and air-packaged meat. We found statistically significant strong correlations (up to 99%) between some of the VOCs and the bacterial contamination. The concentrations of these VOCs increased linearly with the bacterial numbers. This study is a first step toward replacing the time-consuming plate counting by fast headspace air measurements, where the bacterial spoilage can be determined within minutes instead of days.

Bacteria↗
PubMed2002

Characteristic pattern of genetic aberrations in ovarian granulosa cell tumors.

The cytogenetic abnormalities of granulosa cell tumors (GCT) of the ovary are only partially known. Up to now, mainly numerical chromosomal aberrations have been described. Therefore we performed a comprehensive study on paraffin-embedded material of 20 GCT (17 adult, 3 juvenile; patient age between 16 and 78 y) combining comparative genomic hybridization (CGH); fluorescence in situ hybridization (FISH) using DNA-specific probes for chromosome 12, 17, 22, and X; DNA cytometry; and immunohistochemistry (inhibin, p53, Ki67). By DNA cytometry, 16 of 20 tumors (80%) were diploid. However, 6 of 16 diploid tumors (37%) showed aberrations by FISH. FISH revealed monosomy 22 in 8/18 cases (40%); trisomy 12 in 5/20 (25%); monosomy X in 2/20 (10%); and loss of chromosome 17 in one case (5%). The main findings by CGH were gains of chromosomes 12 (6 cases, 33%) and 14 (6 cases, 33%) and losses of chromosomes 22 (7 cases, 35%) and X (1 case, 5%), mostly comprising whole chromosomes or chromosome arms. Inhibin and p53 were expressed in 100% and 95% of the tumors, respectively. The Ki67 index ranged from 0% to 61%. Neither immunohistochemistry, nor DNA cytometry and molecular genetic analysis, provided statistically significant prognostic information. In summary, our study reveals a distinctive pattern of cytogenetic alterations in GCT. Our observations confirm earlier reports that trisomy 12 and 14 are frequent aberrations; however, monosomy 22 seemingly is even more prevalent.

Adolescent↗
PubMed2001

Prognostic relevance of hMLH1, hMSH2, and BAX protein expression in endometrial carcinoma.

Endometrial carcinoma is the most common gynecologic malignancy in perimenopausal and postmenopausal women. A role of mismatch repair genes, like hMLH1 and hMSH2 in their pathogenesis, has been suggested. Loss of their function leads to the accumulation of replication errors (mutator phenotype), which are responsible for further mutations in genes with microsatellite sequences in their coding region, such as Bax. We analyzed the expression of hMLH1, hMSH2, and Bax genes in 89 formalin-fixed paraffin-embedded endometrial carcinomas. The immunostains were scored with regard to percentage of positive tumor cells (0%, <10%, 10 to 50%, >50%), and relative staining intensity (1+, 2+, 3+). The staining results were correlated with clinicopathologic features and survival. Loss of hMSH2 expression (0% positive cells) was observed in 1.1% (1/89) of the tumors; loss of hMLH1 was seen in 12.4% (11/89) of the cases, particularly in endometrioid tumors with mucinous differentation (5/11; 45%; P =.03). No significant association was found between the immunoscores and grade, stage criteria of the International Federation of Obstetrics and Gynecology (FIGO), or age of the patients. Among 11 tumors with loss of Bax expression (12.4%), 4 had also loss of hMLH1 (4/11; 36.4%; P =.017). In multivariate analysis (Cox model), significantly longer survival was found for patients with tumors in FIGO Stage I-II (P <.0001), endometrioid type (P =.001), low grade (P =.001), and absence of hMLH1 expression (P =.027). Our results suggest that loss of function of hMLH1 and Bax occur in a subgroup of endometrial carcinoma. In addition to the classical prognostic factors, absence of hMLH1 expression is associated with better outcome of patients.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Human breath isoprene and its relation to blood cholesterol levels: new measurements and modeling.

Numerous publications have described measurements of breath isoprene in humans, and there has been a hope that breath isoprene analyses could be a noninvasive diagnostic tool to assess blood cholesterol levels or cholesterol synthesis rate. However, significant analytic problems in breath isoprene analysis and variability in isoprene levels with age, exercise, diet, etc., have limited the usefulness of these measurements. Here, we have applied proton transfer reaction-mass spectrometry to this problem, allowing on-line detection of breath isoprene. We show that breath isoprene concentration increases within a few seconds after exercise is started as a result of a rapid increase in heart rate and then reaches a lower steady state when breath rate stabilizes. Additional experiments demonstrated that increases in heart rate associated with standing after reclining or sleeping are associated with increased breath isoprene concentrations. An isoprene gas-exchange model was developed and shows excellent fit to breath isoprene levels measured during exercise. In a preliminary experiment, we demonstrated that atorvastatin therapy leads to a decrease in serum cholesterol and low-density-lipoprotein levels and a parallel decrease in breath isoprene levels. This work suggests that there is constant endogenous production of isoprene during the day and night and reaffirms the possibility that breath isoprene can be a noninvasive marker of cholesterologenesis if care is taken to measure breath isoprene under standard conditions at constant heart rate.

Anticholesteremic Agents↗
PubMed2000

Immunohistochemical analysis of drug resistance-associated proteins in ovarian carcinomas.

Loss of function of the tumor suppressor gene p53, increased expression of glutathione-S-transferase pi (GST7pi) and the major vault protein are involved in drug resistance of ovarian carcinomas. However, a study comparing these factors has not yet been performed. Therefore, paraffin-embedded material of 213 ovarian tumors with well-documented follow-up was used for immunohistochemical analysis of p53 protein, GSTpi, and major vault protein (antibodies LRP-56, LMR-5). Forty-six percent of the cases showed nuclear p53 accumulation. Strong immunoreactivity for GSTpi, LRP-56, and LMR-5 was seen in 50%, 36%, and 47%, respectively. p53 positivity was most often found in serous carcinomas (p < 0.05). Strong GSTpi expression was the only factor that correlated with clinical resistance to chemotherapy (p = 0.04). In the whole group, as well as in FIGO III cases stratified for residual disease < or = and >2 cm, p53 and GSTpi correlated with an adverse outcome (p = 0.01 for p53 and p = 0.04 for GSTpi). Strong LRP-56 or LMR-5 staining was associated with a tendency towards poorer prognosis, without reaching statistical significance. In multivariate analysis for FIGO III, only residual disease and p53 proved to be independent prognostic factors. Our observations confirm the prognostic significance of p53 accumulation in ovarian carcinomas. Only GSTpi immunoreactivity was significantly correlated with drug resistance.

Adenocarcinoma, Mucinous↗
PubMed2000

Grading of ovarian carcinomas.

Grading of ovarian carcinomas can have important implications for therapeutic decisions, in particular in International Federation of Gynecology and Obstetrics (FIGO) stage I. However, there are no universally accepted grading guidelines for this type of cancer. We applied the grading system suggested by Shimizu et al. (1) to a series of ovarian carcinomas from a single institution to evaluate its prognostic significance in relation to other predictive factors. One hundred ninety-two cases of ovarian carcinomas were studied, including all major histologic types. The histologic slides were evaluated with regard to architecture (glandular = 1 point, papillary = 2 points, solid = 3 points), nuclear pleomorphism (nuclear variability < or = 2:1 = 1 point, intermediate nuclei = 2 points, nuclear variability > or = 4:1 = 3 points), and mitotic activity per 10 high-power fields using objective 40x, ocular 10x/20 (0-7 mitoses = 1 point, 8-18 mitoses = 2 points, > or = 9 mitoses = 3 points). Carcinomas with a total score of 3-5 points were designated as grade I, 6-7 points were designated as grade II, and 8-9 points were designated as grade III. Kaplan-Meier curves showed the following 5-year survival rates: grade I (n = 42) 88%, grade II (n = 98) 60%, grade III (n = 52) 38% (p < 0.0001); stage I 90%, stage II 60%, stage III 38%, stage IV 10% (p < 0.0001); residual disease < or = 2 cm 67% and > or = 2 cm 27% (p < 0.0001). Multivariate Cox analysis revealed that grade (p < 0.0002), as well as nuclear pleomorphism alone (p < 0.0001), both provided statistically significant independent prognostic information. Our observations showed that the grading system used can be easily applied to all histologic types of ovarian carcinomas yielding prognostically relevant information and can be incorporated into routine diagnostic practice.

Adenocarcinoma, Clear Cell↗
PubMed1976

Possible linkage of HL-A and GLO.

In 21 informative families with 60 children, a possible linkage between HL-A and GLO was found (recombination fraction approximatively 0.15). The sequence of the loci on chromosome 6 might be GLO, HL-A, PGM3, MNSs.

Adult↗