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J Roth

Publications and source records attributed to J Roth.

At least 469 records · Page 26Linked to original sources
PubMed1987

Glucosidase II, a protein of the endoplasmic reticulum with high mannose oligosaccharide chains and a rapid turnover.

Glucosidase II is regarded as a resident protein of the endoplasmatic reticulum. The enzyme removes alpha-1-3-linked glucose from high mannose oligosaccharides N-linked to asparagine residues of glycoproteins. Monospecific antibodies raised against the pig kidney enzyme are used to study the metabolism of the enzyme in a rat hepatoma cell line. These antiglucosidase II antibodies specifically immune precipitate glucosidase II as a 100,000-Da species from [35S]methionine-labeled cells. In addition, protein blotting and immune staining of cell extracts from both rat liver and human and rat hepatoma cell lines show identity in apparent Mr (100,000). Glucosidase II synthesized in the presence of tunicamycin is approximately 94,000 Da, indicating the presence of one or more N-linked oligosaccharide chains. Cell-free protein synthesis of rat hepatoma total RNA demonstrates that glucosidase II is synthesized as a slightly higher molecular weight species as compared to the polypeptide synthesized in whole cells in the presence of tunicamycin, indicating that the enzyme has a cleavable signal sequence. Using a pulse-chase protocol, the apparent molecular weight does not change upon longer chase periods. In addition, the 100,000-Da protein remains sensitive to endo-beta-N-acetylglucosaminidase H regardless of prolonged chase periods. The cells incorporate [3H]mannose into the enzyme; after release with endo-beta-N-acetylglucosaminidase H, most of the radioactivity comigrates with Glc1-Man9-GlcNAc on a gel filtration column. Phase separation in Triton X-114 shows a partition between the aqueous and the Triton phase, the major portion being separated in the aqueous phase. In rat hepatoma cells glucosidase II has a half-life of 50 min. This value is not altered if the cells are grown in the presence of monensin nor of methyl-deoxynoijirimycin. However, tunicamycin and low concentrations or primaquine (raising the pH of acidic compartments) causes a 100% increase in half-life of glucosidase II. We conclude that glucosidase II is a hydrophilic, probably not a transmembrane membrane, protein with a short half-life. It is the first example of an oligosaccharide-processing enzyme not being an integral membrane protein.

Animals↗
PubMed1987

Light microscopical detection of antigens and lectin binding sites with gold-labelled reagents on semi-thin Lowicryl K4M sections: usefulness of the photochemical silver reaction for signal amplification.

In the present study, we have investigated the applicability of semi-thin sections from low temperature Lowicryl K4M-embedded tissues for cytochemical labelling with protein A-gold and lectin-gold complexes. In order to ensure the best possible signal-to-noise ratio antibodies, protein A-gold and lectin-gold were applied in concentrations used for labelling at the electron microscope level. Furthermore, due to the lack of an appropriate chemical procedure for resin removal, untreated semi-thin sections were incubated. Under such conditions, semi-thin sections displayed either no visible staining or only a faint incomplete staining. However, following photochemical silver reaction, the latent or faint incomplete staining was rendered visible in most cases. It is concluded that the same block of Lowicryl K4M-embedded tissue and the same labelling reagents can be used for both light and electron microscopical cytochemical studies. At the light microscopical level, a high degree of structural and specific staining information is obtained. The reactivity of cellular components with antibodies or lectins is preserved even after years of storage of the blocks or slides containing semi-thin sections.

Amylases↗
PubMed1987

The management of Crohn's colitis with colonogastric fistula. Report of a case.

Colonogastric fistula, more commonly called "gastrocolic," is a rare complication of Crohn's colitis. The 17th incidence of this fistula is reported. Fecal halitosis is a prominent symptom. Barium enema is the most accurate diagnostic tool. Colonoscopy plays a role in delineating surgical therapy. The stomach resection is described. Because of its pathogenesis, the authors prefer to call this "colonogastric" fistula, rather than gastrocolic fistula.

Adult↗
PubMed1987

Monoclonal antibodies to polysialic acid reveal epitope sharing between invasive pathogenic bacteria, differentiating cells and tumor cells.

Monoclonal antibodies (mAb) for rapid diagnosis and detection of invasive bacteria and identification of pathogenic factors in infectious disease are equally important in medical microbiology and clinical pathology and may even provide a breakthrough in basic medical and cell biology research. Such a situation evolved from the application of a unique mAb against the poorly immunogenic homopolymers of alpha 2,8-linked sialic acid of Escherichia coli K1 and meningococci group B capsules which could be derived from immune-hyperreactive NZB-autoimmune mice. The cross-reactivity of this mAb with identical polysialic acid (polySA) units of the neural cell adhesion molecule (N-CAM) revealed antigenic mimicry as the basis for the escape of the above-mentioned bacteria from host immune response and immune defense. The mAb proved to be a specific and sensitive diagnostic reagent as well as a very efficient therapeutic agent in experimental E. coli K1 and meningococcal group B infections in mice. Furthermore, the mAb was found to react exclusively with long-chain polySA units characteristic of the embryonic form of N-CAM. This led to the discovery that the embryonic form of N-CAM is present outside neural tissue in the mesodermally derived kidney where it is specifically expressed during embryonic organ differentiation and reexpressed under conditions of malignant growth in nephroblastoma. Therefore, the embryonic form of N-CAM represents an onco-differentiation antigen in kidney.

Animals↗
PubMed1987

Frog brain and liver show evolutionary conservation of tissue-specific differences among insulin receptors.

The insulin receptors of frog brain and liver show features typical of other insulin receptors with regard to affinity and specificity of binding to insulins and proinsulin, solubility in Triton X-100, binding to and elution from wheat germ agglutinin, and insulin-sensitive tyrosine kinase activity. Likewise, the brain and liver receptors differ from one another in electrophoretic mobility and susceptibility to treatment with neuraminidase, analogous to brain and liver receptors of reptiles, birds, and mammals; while the functional implications of these differences are unknown, their evolutionary conservation for 400-500 million years suggests the possibility that they might have importance.

Animals↗
PubMed1987

The second ten years: long-term risks of breast conservation in early breast cancer.

A retrospective cooperative study was undertaken to analyze the fate of 300 clinical Stage I and II breast cancer patients who were alive and apparently cured with both breasts preserved, 10 years following primary limited surgery with irradiation. All patients had been treated by tumor excision, with or without axillary dissection, followed by megavoltage radiation therapy. Follow-up ranged from 10.5 to 26 years, median 14.5 years. The overall actuarial survival (Kaplan-Meier) of the 300 "cured" patients was 86% at 15 years and 78% at 20 years, with 38.5% of deaths attributable to breast cancer. The actuarial probability of remaining free of metastatic disease was 91% at both 15 and 20 years, independent of age or clinical stage. Sixteen patients (5.3%) developed recurrent cancer in the treated breast beyond the tenth year, the actuarial probability of remaining free of breast recurrence being 94% and 90% at 15 and 20 years, respectively. Contralateral breast cancers developed during the second decade in 5 patients, with a cumulative risk of 6.5% at 20 years. Significant treatment-related problems appeared during the second decade in 5 patients, including one chest wall sarcoma; all of these patients had received at least 60 Gy to breast and regional nodal areas. A comparison of these results with those in the literature allowed the following conclusions to be drawn: (a) the risk of death, as well as breast cancer mortality during the second decade, are similar for both conservatively and radically treated patients with Stage I and II breast cancer; (b) the risk of contralateral breast cancer is not greater than that observed following primary radical surgery without radiation therapy; (c) ipsilateral breast "recurrences" continue to occur at about 1% per year during the second decade. Such late recurrences are highly operable and have a favorable prognosis; (d) late progression of treatment-related sequelae is uncommon. This analysis supports the continued use of breast-conserving surgery with radiation therapy in the treatment of Stage I and II breast cancer.

Breast Neoplasms↗
PubMed1987

Delivery of intraoperative radiation therapy after pneumonectomy: experimental observations and early clinical results.

Intraoperative radiation therapy (IORT) is capable of delivering high doses of radiation to mediastinal structures while sparing lung parenchyma, heart, and other locoregional tissues. A canine model of pulmonary resection and IORT was investigated by performing a pneumonectomy in 15 adult foxhounds followed by 0 cGy, 2,000 cGy, 3,000 cGy, 4,000 cGy. No clinical complications developed in 4 animals in the 2,000-cGy group. However, 2 of the 8 animals given a high dose died of esophageal hemorrhage or carinal necrosis. Esophagitis occurred in 10 of 12 animals, and none of the animals experienced bronchial stump dehiscence. In a limited Phase I protocol, 4 patients with non-small cell lung cancer were treated with resection and 2,500 cGy of IORT to two separate ports encompassing the superior and inferior mediastinum. Two patients experienced life-threatening bronchopleural fistulas, and 2 patients died as a consequence of esophageal problems. One patients had recurrence with brain metastases, and the 1 long-term survivor is free from disease. As opposed to the animal model of thoracic IORT, the clinical study demonstrated major toxicity with respiratory and esophageal morbidity. The therapeutic usefulness of thoracic IORT in the management of lung cancer must be questioned in view of this small but consistent series of patients. Further carefully designed clinical studies using lower doses of IORT are needed.

Adult↗
PubMed1987

Polysialic acid units are spatially and temporally expressed in developing postnatal rat kidney.

We report the presence of alpha(2----8)-linked polysialic acid as detected with a monoclonal antibody outside the nervous tissue in the postnatal developing rat kidney. By immunoblot analysis, the reactivity was confined to a broad band of apparent molecular mass 200-250 kDa. By immunohistochemistry, the polysialic acid units were found throughout the ureteric bud-derived collecting duct system. In developing nephrons derived from the metanephrogenic mesenchyme, polysialic acid units were only regionally and transiently expressed. Furthermore, the expression of polysialic acid units was developmentally regulated, as evidenced by their gradual disappearance concomitant with postnatal kidney maturation. These findings suggest a possible role for polysialic acid units in cell-cell contact-mediated renal differentiation processes.

Aging↗
PubMed1987

Detection of terminal N-linked N-acetylglucosamine residues in the Golgi apparatus using galactosyltransferase and endoglucosaminidase F/peptide N-glycosidase F: adaptation of a biochemical approach to electron microscopy.

Purified human milk beta-N-acetylglucosaminide beta 1, 4 galactosyltransferase (EC 2.4.1.38) was used to galactosylate N-acetylglucosamine (GlcNAc) residues present in ultra-thin sections of Lowicryl K4M-embedded rat and pig liver. Both endogenous galactose and galactosylated transferase products could be revealed by Ricinus communis lectin I-gold complexes (RcL I-g15). Without galactosyltransferase (GT) treatment, labeling for galactose (gal) was limited to the trans region of rat and pig hepatocyte Golgi apparatus. After exposure to GT, additional labeling was found over cis Golgi apparatus cisternae. RcL I-g15 labeling was sensitive to a purified preparation of endoglucosaminidase F/peptide N-glycosidase F (at pH 9). This indicates that endogenous gal and gal transferred by GT to terminal GlcNAc residues are present N-linked oligosaccharides. The RcL I-g15 labeling produced by GT was insensitive to extensive washing with solutions containing either EDTA and urea or SDS and 2-mercaptoethanol or 0.1 M GlcNAc. Substrate inhibition studies showed that 50 mM GlcNAc specifically inhibited the additional RcL I-g15 labeling produced by GT. The use of purified glycosyltransferases therefore appears to allow specific detection of oligosaccharide substrates and their high resolution localization in thin sections by electron microscopy.

Acetylglucosamine↗
PubMed1987

Immunocytochemistry of pituitary tumors.

Pituitary tumors from 376 patients were investigated, using immunocytochemical techniques at the light and electron microscopic level, and autoradiography combined with immunocytochemistry for localizing somatostatin (SRIH) receptors. Prolactinomas, growth hormone-secreting adenomas causing acromegaly, and hormonally inactive adenomas were most frequently observed (153, 86, and 90 tumors, respectively). Among the latter, we could distinguish "alpha-only adenomas," many of which were oncocytomas. At the light and electron microscopic levels, cells containing (and presumably producing) simultaneously both prolactin and growth hormone, and cells containing exclusively either prolactin or growth hormone, could be demonstrated. In addition, a highly variable number and distribution of SRIH receptors could be shown in tumors secreting prolactin, growth hormone, and in tumors not associated with symptoms caused by inappropriate hormone secretion. The systematic combination of clinical, radiological, and biological techniques has currently brought great progress in the behavior and therapeutic concepts of pituitary lesions, and promises new achievements in the near future.

Adenoma↗
PubMed1987

The insulin receptors of chick embryo show tissue-specific structural differences which parallel those of the insulin-like growth factor I receptors.

Since specific binding to receptors and biological effects of insulin and insulin-like growth factors (IGFs) are demonstrable soon after the neural tube closes and organogenesis begins in the chick embryo, in the present study we have analyzed the structural characteristics and specificity of the receptors for insulin and IGFs at this early stage of development. We show that membranes from newly differentiated chick embryo tissues (day 6 brain, day 6 heart, day 8 liver, day 12 skeletal muscle) as well as whole embryos postneurulation (day 2, stage of 27-30 somites) have two populations of receptors with distinct specificity: insulin and type I IGF (IGF-I) receptors. Both insulin and IGF-I alpha-subunits, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, had tissue-dependent heterogeneity in Mr (liver greater than heart = skeletal muscle greater than brain) ranging from 138 kilodaltons (kDa) to 129 kDa. Desialylation of the receptors by treatment with neuraminidase produced a significant change in the Mr of the alpha-subunits in liver and heart but not in brain or the whole day 2 embryo. In each tissue the pattern for insulin receptors and IGF-I receptors was strikingly similar. Our studies raise the possibility that postranslational modifications of the insulin and IGF-I receptors, characteristic of terminally differentiated tissues, are already present in early organogenesis. Further, structural heterogeneity of the binding subunit of these receptors among tissues appears to be widespread and not exclusive to the brain receptor. An insulin receptor with features similar to the neural type is the only one detected in embryos at the beginning of organogenesis (day 2). The functional implication of this developmental tissue-specific regulation of insulin and IGF-I receptors, is still speculative. Its possible importance is suggested by the fact that it occurs embryologically early and affects both insulin and IGF-I receptors in parallel.

Animals↗
PubMed1987

[1985 dosimetry comparison at 12 radio-oncology centers in Switzerland].

In 1985 a working group of medical radiophysicists from the Swiss Society for Radiobiology and Radiophysics performed for the second time a dosimetric comparison at 13 irradiation units used in twelve radio-oncologic centres of Switzerland. The dose and dose distribution were measured in a specified target volume in an anthropomorphic phantom, also considering the irradiation planning. On the whole, the results show the expected variations. The average error of positioning towards the specified target volume was 4mm. The differences between the doses calculated for the individual points according to the irradiation scheme and the doses measured in these points amount on an average to less than 5%.

Cancer Care Facilities↗
PubMed1987

Codistribution of galactosyl- and sialyltransferase: reorganization of trans Golgi apparatus elements in hepatocytes in intact liver and cell culture.

The intracellular distribution of galactosyl- and sialyltransferase was investigated in rat hepatocytes of intact liver, primary monolayer cultures of freshly isolated hepatocytes, in a nontumorigenic hepatocyte cell line and in a hepatoma cell line. The two glycosyltransferases were detected by immunofluorescence using affinity-purified rabbit antibodies. Indirect double immunofluorescence showed that both terminal glycosyltransferases were identically codistributed in the same cell. This codistribution was always observed regardless of the cell type investigated, and in both stationary and migrating cells. The immunofluorescence pattern for both galactosyl- and sialyltransferase was found to be different in hepatocytes in vivo compared to hepatocytes grown in vitro. In hepatocytes of intact liver a spot-like cytoplasmic fluorescence was observed, whereas in cultured normal hepatocytes a perinuclear fluorescence from which an extensive tubular network radiated far into the cytoplasm existed. Cultured hepatoma cells also exhibited an extensive cytoplasmic fluorescence, which in contrast to the normal hepatocytes was rather diffuse. We conclude that (a) galactosyl- and sialyltransferase are codistributed in rat hepatocytes, and (b) a reorganization of (trans) Golgi apparatus elements containing both terminal glycosyltransferases occurs under conditions of in vitro growth and malignant transformation.

Animals↗
PubMed1987

Streptococcal protein G-gold complex: comparison with staphylococcal protein A-gold complex for spot blotting and immunolabeling.

Protein G, a cell wall protein isolated from human group G streptococci strain G148, binds in a similar manner as protein A from Staphylococcus aureus to the Fc portion of IgG molecules. Indeed, protein G has been proposed as a superior Fc binding protein due to its broader species reactivity. Thus, we have prepared a complex of protein G with particles of colloidal gold and determined its applicability for spot-blot analysis and postembedding immunolabeling by comparing it with protein A-gold complex. By spot-blot analysis no difference in binding of protein G-gold or protein A-gold to IgG molecules from a whole spectrum of animal species was observed. Moreover, using rabbit, sheep, or goat anti-rat albumin antibodies to detect nitrocellulose-immobilized rat albumin or antigenic sites in paraffin and Lowicryl K4M thin sections from rat liver, no difference was found with protein G-gold or protein A-gold. Similarly, no difference in binding to protein G-gold or protein A-gold was observed with a battery of monoclonal antibodies. However, in contrast to expectations, protein A-gold reacted well with both sheep and goat IgG molecules; indeed, for the light and electron microscopic localization of albumin with sheep or goat antibodies it was as efficient as protein G-gold. These results demonstrate, therefore, that both protein G-gold and protein A-gold are useful second step reagents for immunolabeling and that protein G-gold was not a superior probe in the systems tested.

Albumins↗