Biomedical subjects

A Schauer

Publications and source records attributed to A Schauer.

At least 73 records · Page 4Linked to original sources

PubMed1991

Endometrial stromal sarcoma of the uterus.

Uterine sarcomas are rare tumors constituting 1-3% of all uterine malignancies. These tumors are characterized by aggressive growth and by poor overall prognosis. There is much controversy concerning diagnostic criteria and the great variation in histology, as well as the role of radiotherapy and chemotherapy in the management of these tumors. We report a case of endometrial stromal sarcoma of the uterus in a 45-year-old woman. Total abdominal hysterectomy, bilateral salpingo-oophorectomy and pelvic lymphadenectomy was performed, followed by adjuvant radiotherapy and tamoxifen treatment. The patient has now been seen regularly for 2 years from the start of the treatment and at present there is no evidence of disease.

Antineoplastic Agents↗

PubMed1991

[Helicobacter pylori colonization in surgical patients].

The prevalence of Helicobacter pylori (HP) was examined in 387 patients undergoing endoscopy of the upper gastrointestinal tract. Of central interest was the question to which extent surgical intervention influences the colonisation of the gastric mucosa with HP. The bacillic status was appraised using double microbiological examinations, histological determination and the CLO-test. In 229 patients a 13C-urea-breath test was also carried out (sensitivity 98%). HP could be detected in 90% of all patients presenting with duodenal ulcers as well as in 70% of patients with gastric ulcers, whereas in those patients in whom a lesion of the upper gastrointestinal tract could be excluded through endoscopy. HP was found in only 27%. The prevalence of HP did not increase with age. In patients having undergone distal gastric resection due to gastric ulcers, HP was only rarely found (19%) in the mucosa in the vicinity of the anastomosis following removal of the apparently pathogenetically important antrum mucosa. There was no association between anastomosis ulcers and bacillic colonisation. Following selective proximal vagotomy in patients with duodenal ulcers, HP was found in 80% of all cases. In these patients there was also no association between recurrent ulceration and a HP-positive status. Our results describe the postoperative HP-status after different surgical procedures of ulcer therapy: whereas a distal gastric resection removes the antrum mucosa, which provides the necessary environmental milieu, the HP-colonisation rate after selective proximal vagotomy is similar to that in non-operated ulcer disease.

Adolescent↗

PubMed1990

Vaginosonography for early detection of endometrial carcinoma?

In 103 women with postmenopausal bleeding and 283 postmenopausal women without bleeding maximum endometrial thickness was measured by vaginosonography. All patients with postmenopausal bleeding and all women without atypical bleeding but with an endometrium thicker than 4 mm or with some other indication for further investigation underwent curettage. The curettings were examined histologically. All histologically classified endometrial carcinomas were associated with an endometrial thickness of at least 4 mm. Endometrial cancer was found in 12.6% in the postmenopausal bleeding group (n = 103) and in 3.5% in the symptom-free group (n = 283). Vaginosonography is thus a good method of screening for uterine neoplasms in presymptomatic women--those with endometrial thickness of 4 mm or greater should undergo curettage and histological examination.

Aged↗

PubMed1990

Heterogeneity of immunoglobulin gene rearrangements in B-cell lymphomas.

We have examined 69 B-cell non-Hodgkin's lymphomas (NHL) for rearrangements of the immunoglobulin (Ig) or T-cell antigen receptor (TCR) genes. The lymphomas were assigned to the categories of the Kiel classification and their B-cell nature was confirmed by immunostaining. Only 2 cases (with CLL) displayed clonal T beta-chain TCR gene rearrangements together with rearranged heavy- and light-chain Ig genes. The remaining 67 lymphomas had a germline beta-chain TCR-gene configuration. Three different patterns of Ig gene rearrangements were identified; (A) presence of both heavy- and light-chain rearrangements (H+L+); (B) rearrangement of heavy-chain gene only (H+L-); (C) heavy- and light-chain genes in germline configuration (H-L-). All the 45 low-grade NHLs and the 4 immunoblastic lymphomas exhibited pattern A and all had their kappa gene rearranged or deleted. Of 24 low-grade lymphomas tested, 13 (54%) had an addition rearrangement of the lambda light-chain gene. In contrast, the 19 high-grade centroblastic (cb) B-NHLs had distinct patterns of Ig-gene rearrangement: 12 with pattern A, 4 with B and 2 with C. In this group only 2 of 17 (12%) cases analyzed had evidence of lambda light-chain rearrangement whereas 12 of 18 (67%) had a kappa gene rearrangement or deletion. In one case expressing sIgM/lambda and with heavy chain Ig-rearrangement, no DNA was available for Ig light-chain analysis.

Adolescent↗

PubMed1990

c-erbB2 expression in correlation to other biological parameters of breast cancer.

On the prognostic value of c-erbB2-encoded protein p185 in breast cancer there are controversal opinions. With the outlook of an evaluation of the prognostic value of p185 expression in breast cancer the relationships between p185 expression and known prognosis factors were investigated. Using polyclonal antibody against p185 33% out of 163 primary breast carcinomas are p185-positive. Within the various histological types of tumors the percentage of p185 expression differs. It is suggested that p185 indicates a certain type of biological behavior and plays a role in the pathogenesis of breast cancer. Thus the determination of p185 could allow definition of biological subclasses. A statistically significant correlation between expression of p185 and the presence of lymph node metastases or tumor size can not be proved. Nevertheless p185 expression is increased in cases with more than three positive lymph nodes. Expression of p185 correlates statistically significantly positively with histological grade and epidermal growth factor receptor, and negatively with steroid receptor status. Furthermore, high-proliferating tumors are more common in p185-positive cases than in p185-negative cases. It is concluded that p185 may be associated with an increased malignancy and proliferation activity of tumors.

Breast Neoplasms↗

PubMed1990

Growth-stimulating effects of recombinant human growth hormone in children with end-stage renal disease.

Because patients with uremia have evidence for growth hormone resistance, we investigated whether this resistance can be overcome by administration of recombinant human growth hormone in supraphysiologic doses in children with severe uremia. Nine stunted children with end-stage renal disease (median age 5.8 years, median bone age 2.7 years) were treated with recombinant human growth hormone, 4 IU/m2/day subcutaneously, for a period of 1 year. Median height velocity was increased from 4.4 cm/yr before therapy to 8.0 cm/yr during treatment. Negative values for height velocity standard deviation scores for chronologic age were improved from a median of -2.6 to +1.5 without advancing bone age more than chronologic age. The growth hormone-insulin-like growth factor I resistance may be explained in part by the increased serum concentration of the high molecular weight insulin-like growth factor binding protein despite normal insulin-like growth factor I serum concentration. Treatment with recombinant human growth hormone improved the ratio between the serum concentrations of insulin-like growth factor I and its binding protein, and normalized the somatomedin bioactivity in the growth cartilage bioassay.

Age Determination by Skeleton↗

PubMed1990

[Malignant skin and soft tissue tumors--function preserving surgery--pathomorphologic aspects].

Special aspects of the localization and spontaneous regression of primaries of malignant melanoma, further more aspects of the pTNM-system as well as problems concerning perfusion therapy are pointed out and discussed. In the following the different biology of squamous cell and basal cell cancer dependent also on the localization of the primaries is described and discussed. Concerning the soft tissue tumor part immunohistochemical methods for the management of differential diagnosis are demonstrated and evaluated. These methods can be used for the delineation of extranodal Hodgkin and non-Hodgkin lymphoma infiltration from soft tissue tumors and in the differential diagnosis of polymorphous, spindle cell and epitheloid differentiated soft tissue tumors. Finally the problem of tumor grading and new grading systems (score) according to Coindre et al. are demonstrated and discussed.

Biomarkers, Tumor↗

PubMed1990

Endogenous lectins with specificity to beta-galactosides and alpha- or beta-N-acetyl-galactosaminides in human breast cancer. Their glycohistochemical detection in tissue sections by synthetically different types of neoglycoproteins, their quantitation on cultured cells by neoglycoenzymes and their usefulness as targets in lectin-mediated phototherapy in vitro.

Endogenous lectins may augment the panel of tumor markers. Specific protein-carbohydrate interactions especially involve carbohydrate moieties that are located at sequence termini, e.g. D-galactose and N-acetyl-D-galactosamine. Respective endogenous lectins can be detected by suitably constructed neoglycoproteins. In order to evaluate the influence of sugar and label density as well as coupling mode of the carbohydrate moiety to the carrier protein for lectin localization in histopathology, four different types of neoglycoproteins, carrying beta-galactosides or alpha- and beta-anomers of N-acetyl-D-galactosamine were employed to reveal the presence of specific receptors in invasive ductal mammary carcinomas with propensity for metastasis formation. Staining of tumor cells was more intense than staining of normal cell types. Coupling of the diazo derivatives of p-aminophenyl glycosides led in most cases to the relatively highest extent of staining in terms of number of stained cells and staining intensity. Classified next according to these categories attachment of sugars via p-isothiocyanato derivatives or via an aliphatic linker after his reaction with the C6-hydroxyl group of the sugar moiety was rather equally well effective, whereas reductive amination with concomitant ring opening at the reducing end of the disaccharide lactose resulted in neoglycoproteins, yielding the lowest extent of staining. The alpha-anomer is preferred as a ligand to endogenous lectins of tumor cells to the beta-anomer of N-acetyl-D-galactosamine. To reduce the number of steps in glycohistochemical processing, glycosylated enzymes were successfully employed. They also allowed to measure the lectin density on breast carcinoma cells, leading to rational selection for demonstrated lectin-mediated targeting of neoglycoprotein-hematoporphyrin conjugates. Immobilization of ligands as an approach to prepare histochemically valuable reagents to localize respective receptors is not confined to tumor lectinology, as emphasized by additional application of hormone-protein conjugates, termed neohormoproteins.

Acetylgalactosamine↗

PubMed1989

Tissue-specific expression of sialyltransferases.

Three sialyltransferases which attach terminal sialic acids to glycoprotein sugar chains are shown to exhibit striking differential expression in seven tissues of the rat. Using cDNA probes for the Gal beta 1,4GlcNAc alpha-2,6-sialytransferase which forms a NeuAc alpha 2-6Gal beta 1-4GlcNAc sequence on N-linked sugar chains, three different sized mRNAs are detected, two of which (4.7 and 4.3 kilobases (kb] have high homology along the full length, and a third (3.6 kb, in kidney) which is missing the 5' region corresponding to 45% of the NH2-terminal coding sequence. The 4.7- and 4.3-kb mRNAs exhibit differential expression of over 50-fold with the highest levels in liver and lowest in brain and heart. Assays for enzyme activity in tissue homogenates show high correspondence to the levels of mRNA. Evidence of tissue-specific expression was also obtained for two other sialyltransferases which form the NeuAc alpha 2-3Gal beta 1-4/3GlcNAc and NeuAc alpha 2-3Gal beta 1-3GalNAc sequences on N-linked and O-linked sugar chains, respectively. Comparison of the ratios of the three enzymes in several tissues suggests that they are expressed independently. The results are discussed for their relevance to cellular control of terminal glycosylation sequences on glycoproteins and glycolipids.

Animals↗

PubMed1989

Therapy of early breast cancer: preliminary results of the German Breast Cancer Study.

The German Breast Cancer Study Group has a large, homogeneous patient population with pT1 pN0 breast cancers who have undergone a detailed pathohistological work-up and uniform treatment. Seventy institutions take part in this study, mostly community hospitals. All pathologic specimens are reviewed by the Pathology Reference Center. Moreover, in order to improve the quality of radiation therapy, all dosimetric data, radiation protocols, and localization, and verification films are reviewed by the Radiotherapeutic Study Centre. By January 31, 1988, 762 patients had been recruited. At the moment, after an admittedly short follow-up period for the majority of our patients, there is no evidence of differences between the two treatment arms concerning the incidence of local and distant recurrences, contralateral breast cancers, and other malignancies. However, the study demonstrates several unresolved problems, mainly the collection of follow-up data which can arise when many institutions especially community hospitals and general practitioners, are involved in a prospective trial.

Breast Neoplasms↗

PubMed1989

Regulation of tumor necrosis factor gene expression in colorectal adenocarcinoma: in vivo analysis by in situ hybridization.

Tumor necrosis factor (TNF) produced by macrophages is thought to contribute to the host defense against development of cancer. However, since tumor cells themselves are able to produce TNF, it is conceivable that TNF may also play an adverse pathological role in carcinogenesis. To better understand the functional significance of TNF in neoplastic disease, we have determined the cellular source of TNF activity produced in 10 patients with colorectal cancer. Northern blot analysis of RNAs extracted from fresh biopsy specimens revealed detectable TNF mRNA levels in all instances. By using in situ hybridization of frozen sections, scattered cells expressing TNF mRNA could be discerned. Based on morphological criteria, these TNF-positive cells most likely belong to the macrophage lineage. Macrophages in normal tissue surrounding the tumor did not express TNF mRNA, suggesting that macrophage activation occurs locally at the site of neoplastic transformation. Immunohistochemistry using anti-TNF monoclonal antibodies revealed that less than 1% of tumor-infiltrating macrophages synthesize TNF protein. Thus we present evidence that in colorectal cancer only a small proportion of tumor-infiltrating macrophages produces TNF, indicating that the microenvironment of the tumor provides adequate, yet suboptimal, conditions for macrophage activation.

Adenocarcinoma↗

PubMed1989

Improvement of uremic growth failure by recombinant human growth hormone.

Nine stunted prepubertal children with end-stage renal failure were treated by rhGH in supraphysiological doses (4 U/m2/day s.c.) for a period of six to nine months. The six-month data from these children indicated that exogenous rhGH significantly improved the growth rate in all children (mean height velocity SDS before therapy, -2.8; during the treatment period, +2.5). This effect was accompanied by a significant increase in serum somatomedin bioactivity. Low normal basal serum IGF I concentrations were increased by rhGH. Elevated basal serum IGF II concentrations were further increased by rhGH treatment. The pharmacokinetic profile of rhGH in uremia resembles that of the non-uremic state; no accumulation was seen after 14 days of treatment. Glucose tolerance did not change, and insulin levels remained stable throughout the six-month observation period. No rhGH antibodies were detected. Although these short-term results are very encouraging, the effects of rhGH on the prognosis for final height need to be assessed over a longer period of time.

Child↗

PubMed1988

Visualizing gene expression in time and space in the filamentous bacterium Streptomyces coelicolor.

Streptomycetes are prokaryotic microorganisms that exhibit a complex, mycelial fungus-like cycle of morphological differentiation. Development involves at least two spatially separated types of cells: the branching hyphae of the substrate mycelium, which penetrate the stratum upon which the colony feeds, and the upwardly protruding hyphae of the aerial mycelium, which undergo metamorphosis into spores. The luciferase-encoding luxA and luxB operon of the luminescent marine bacterium Vibrio harveyi was used as a promoter probe to visualize gene expression in differentiating colonies of Streptomyces coelicolor. Promoters for developmental genes of several kinds gave distinctive temporal and spatial patterns of light emission.

DNA, Bacterial↗

PubMed1988

[Vaginal tumor--an initial manifestation of malignant histiocytosis].

An anaplastic vaginal tumour was diagnosed in a 29-year-old woman. Before the planned operation leukocytosis and thrombocytopenia developed and further diagnostic tests revealed malignant histiocytosis with bone-marrow infiltration, leukaemic wash-out and tumour formation in the lower pelvis. Intensive chemotherapy, as for acute myeloid leukaemia, achieved full remission. The case demonstrates that, although rare, tumorous organ infiltration may be the initial manifestation of malignant histiocytosis. Its early diagnosis and treatment decisively affects the prognosis.

Adult↗

PubMed1988

Endogenous sugar-binding proteins in human breast tissue and benign and malignant breast lesions.

Binding of carbohydrate moieties was detected in tissue sections of human breast by employing two types of labeled ligands: neoglycoproteins (chemically glycosylated, histochemically inert carrier protein) and desialylated naturally occurring glycoproteins. Paraffin-embedded, formalin-fixed sections from 40 benign and malignant breast lesions were examined for the presence and distribution of endogenous sugar receptors, employing a panel of 13 biotinylated neoglycoproteins, representing carbohydrates commonly found in naturally occurring glycoconjugates, and four biotinylated glycoproteins. Benign and malignant breast lesions revealed staining with mannosylated carrier neoglycoprotein in comparison to normal breast. A mixed pattern of staining localization and intensity was seen for different types of malignancy with this neoglycoprotein. Similarly, receptors for lactose and N-acetylglucosamine could only be detected within the cytoplasm for certain types of malignancy. Their nuclear localization, however, could also be seen in normal breast specimens. The extent of staining with different glycoproteins, containing different types of galactoside-terminal sugar chains, also appeared to differ between various types of breast cancer. The detection of endogenous sugar receptors by neoglycoproteins is proposed to contribute to an understanding of malignancy-associated alterations in the structure of their potential physiological ligands, the glycoconjugates. Changes in the structure and abundance of such glycoconjugates have commonly been detected with the use of plant lectins in histopathologic studies.

Breast Neoplasms↗

PubMed1988

Ewing's sarcoma metastazing from the right pelvis via the inferior vena cava into the heart: diagnosis and successful surgical treatment.

A case of Ewing's sarcoma metastazing from the pelvis into the heart is presented. Fainting as a result of circulatory obstruction within the right heart was the leading symptom. Open-heart surgery was performed to excise the tumor from the right atrium and the inferior vena cava. Postoperative angiography showed the tumor coming up out of the right iliac vein and growing along the wall of the inferior vena cava.

Bone Neoplasms↗

PubMed1988

Sonographic detection of an asymptomatic rupture of the uterus due to necrosis during the third trimester.

This is a report on the first sonographic detection of a silent rupture of the uterus in the 33rd week of pregnancy of a 35-year-old patient. On the basis of the clear sonographic picture immediate cesarean section was (considered) indicated in spite of lack of clinical symptoms. The intraoperative situs confirmed the sonographic diagnosis of a ruptured uterus related to an old cesarean section, combined with partial necrosis of the lower uterine segment.

Adult↗

PubMed1988

Promoter determining the timing and spatial localization of transcription of a cloned Streptomyces coelicolor gene encoding a spore-associated polypeptide.

Streptomyces coelicolor is a filamentous, gram-positive bacterium that exhibits a complex cycle of morphological differentiation involving the formation of an aerial mycelium of multinucleoid hyphae which undergo septation to form long chains of spores. We report the identification of two proteins of 13 and 3 kilodaltons, designated SapA and SapB, respectively, that are produced during formation of the aerial mycelium and are found in assocation with purified, mature spores. We cloned the structural gene (sapA) for one of these spore-associated proteins. Nucleotide sequence analysis suggests that the 13-kilodalton polypeptide is derived from a larger pre- or preproprotein containing a leader sequence of 37 amino acids. Nuclease protection-hybridization analysis and experiments using the Vibrio harveyi, luciferase-encoding luxAB operon as a gene tag demonstrated that expression of sapA is controlled from a promoter contained within a region of less than 110 base pairs in length, whose transcription start site is located approximately 50 base pairs upstream from the initiation codon for the sapA open reading frame. Transcription of sapA was induced at the time of appearance of the aerial mycelium, and the level of sapA transcripts was significantly reduced in certain mutants blocked in aerial mycelium (bld) and or spore (whi) formation. As further evidence of the association of sapA transcription with morphological differentiation, experiments in which we monitored sapA transcription topographically by use of a sapA-luxAB operon fusion demonstrated a close spatial correlation between colony regions undergoing aerial mycelium formation and zones of sapA-promoted light emission.

Amino Acid Sequence↗