Biomedical subjects
Publications and source records attributed to S Raptis.
A patient with multiple myeloma who developed a myeloproliferative disorder 6 years after initial diagnosis is described. The 2 disorders coexisted for 3 years. Possible explanations for this occurrence are discussed.
delta-Aminolevulinic acid (delta-ALA) synthetase in mouse liver homogenate was significantly (p less than 0.001) higher in the presence of uremic compared with normal plasma, the ratio of the two values being 1.36 +/- 0.24 in 30 paired experiments. This effect does not seem to be due to increased concentrations of urea or creatinine nor to any possible dialyzable substances. Its relationship to the retention of an inducing factor or decreased production of erythropoietin in uremic patients is discussed. A possible inhibitory effect of erythropoietin on liver delta-ALA synthetase is suggested.
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We analysed 29 consecutive cases of primary gastric lymphoma (20 men and 9 women) treated in our unit between January 1977 and May 1983. Median age was 55 years. Abdominal pain and weight loss were the main presenting symptoms while there was no palpable disease in the majority of cases. Upper gastrointestinal radiology was abnormal, but not diagnostic, in all cases. Endoscopy with multiple biopsies was performed in 22 cases; carcinoma was diagnosed in 11, lymphoma in 8 while no diagnosis was made in 3 cases. Twenty six patients underwent laparotomy. Gastrectomy was performed in twenty while the tumour was unresectable in six. Histology was reported as diffuse in 28 cases (16 histiocytic, 8 lymphocytic and 4 mixed) and nodular (lymphocytic) in one. All our patients received multichemotherapy. Complete remission after 6 courses was documented in 18 patients (62%). Neither perforation nor gastrointestinal bleeding was a problem in our series. Eighty four per cent complete responders are predicted to be alive at 4 years. Advanced stage (II2B and IV) and tumour size greater than 10 cm adversely influenced survival. We suggest that in limited primary gastric lymphoma an attempt at 'curative' surgery combined with multichemotherapy currently gives very promising results.
The immune states of 52 patients with myelodysplastic syndromes classified according to the FAB criteria were studied. Serum electrophoresis and immunoelectrophoresis, direct Coombs test, and tests for organ and non-organ specific antibodies were performed. Twenty six patients had immunoglobulin abnormalities: six (11.5%) had monoclonal gammopathy; 17 (32.6%) had polyclonal increases in serum immunoglobulin; while in three (5.8%) immunoglobulin concentrations were decreased. The distribution of immunoglobulin abnormalities among the five myelodysplastic syndrome subtypes was fairly uniform. Results of direct Coombs test were negative in all cases. Organ specific antibodies were not detected in any of the patients tested, although two patients were found positive for antinuclear antibodies. The presence of immunoglobulin abnormalities indicates an involvement of the lymphoplasmatic system in myelodysplastic syndromes.
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The two human insulins of clinical importance are (a) semisynthetic human insulin prepared from pork pancreas by enzymatically substituting threonine for alanine-the last amino acid in the beta chain-thereby transforming pork insulin in vitro to human insulin; and (b) biosynthetic human insulin synthesized biotechnologically in Escherichia coli-K12. Using this latter technique, it is possible to produce mass quantities of highly purified insulin for the treatment of insulin-dependent diabetics, avoiding the problems inherent in supplies of insulin produced from animal pancreas. It has been suggested that to avoid confusion the two human insulins should be called semisynthetic human insulin of pork origin and biosynthetic human insulin of E. coli origin, respectively. These insulins have four advantages over highly purified animal insulins: (a) they induce lower titers of circulating insulin antibodies; (b) their subcutaneous injection is associated with fewer skin reactions; (c) they are absorbed more rapidly from the injection site; and (d) less degradation occurs at the site of injection. These data indicate that newly diagnosed insulin-dependent diabetes, particularly in children, should be treated with either of the two human insulins. The warranty against inadequate supplies of insulin offered by biosynthetic human insulin makes the use of pork insulins unnecessary and beef insulins totally useless.
Ten patients with multiple myeloma (MM) were studied cytogenetically, using the G-banding technique. It was found that five patients had a normal karyotype, whereas five patients exhibited various chromosomal abnormalities. The presence of marker chromosomes was a consistent finding. Among those, the 14q+ marker chromosome was present in three cases, partial or complete trisomy for 1q was detected in four cases, and chromosome #6 was involved in two cases. In one case the 14q+ marker chromosome was determined to result from a translocation between chromosomes #11 and #14. In one patient with Bence Jones kappa multiple myeloma, there was a translocation between chromosomes #2 and #8.
Cytogenetic findings of a primary renal-cell carcinoma are reported. The chromosome number was near triploid and there was tetrasomy for the long arm of chromosomes #1 and #3. The following structural chromosomal abnormalities were identified by the G-banding technique: i(1q), t(3;17), 6q-, 7p+, and a ring chromosome of unknown origin. Chromosomes #1, #3, #6, #7, and #17 involved in this case are often implicated in malignancy.
The proteolytic degradation of labelled pyromycyl polypeptides was investigated in human intact erythroid cells derived from the bone marrow of eight non-thalassaemic patients and the peripheral blood of eleven thalassaemics (eight splenectomized beta thalassaemia heterozygotes and three sickle-cell beta thalassaemics). These abnormal polypeptides are rapidly degraded to soluble trichloroacetic-acid (TCA) fragments with a half-life of 12 min both in bone marrow and peripheral blood. This comes very close to the half-life reported for the puromycyl peptide degradative system in rabbit reticulocytes (15 min). The relationship of the present proteolytic system to the ATP-dependent one, described in rabbit reticulocytes, and to that responsible for the free alpha-chain degradation in beta thalassaemia is discussed.
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The effects of natural secretin (90%) and synthetic secretin as well as impure (10%) and pure (99%) cholecystokinin-pancreozymin (CCK) on net absorption of water, electrolytes, and glucose in human jejunum were studied in 31 normal subjects. An intestinal perfusion technique with a triple-lumen tube was used. Net absorption of water and solute was significantly inhibited by both hormones only with larger doses, pure CCK being less active than impure CCK. A dose-dependent response of water and electrolyte absorption to graded doses of pure CCK was observed, without concomitant inhibition of glucose absorption with lower doses. The findings suggest that secretin and CCK may not be of physiologic importance regarding intestinal absorption in man. The definite changes in intestinal motility and transit rate caused by these hormones seem more likely to result in a reduction of intestinal absorption and an increase in the secretion of water and electrolytes along the proximal small bowel.
The effects of synthetic human gastric I (SHG I) and gastrin-like pentapeptide (PG) on jejunal water, electrolyte, and glucose absorption were studied in 11 normal subjects. The i.v. administration of graded doses of SHG I increased plasma gastrin levels similar to those after food intake and in the Zollinger-Ellison syndrome. SHG I and PG caused no significant changes in the net movement of water and solute. The findings indicate that gastrin has no direct effect on intestinal absorption in normal man, and does not account for the mechanism of diarrhea in the Zollinger-Ellison syndrome.
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In 12 normal volunteers the interaction between the metabolic and cardiovascular effects of adrenaline and either a cardioselective (atenolol 150 mg p. o. for 1 week) or a non-selective beta-blocker with intrinsic sympathomimetic activity (pindolol 15 mg p. o. for 1 week) were studied. Equiactive doses of the beta-blockers were investigated with respect to their metabolic effects. There were profound differences in the metabolic profile of the two substances: the non-cardioselective beta-blocker caused significant inhibition of the lipolytic, glycogenolytic and the growth hormone-releasing effects of adrenaline when compared to the cardioselective agent. The results indicate that, during non-cardioselective beta-blockade, metabolic effects occur which should favourably influence myocardial oxygen consumption by making myocardial performance more economical.
Secretin was determined radioimmunologically in portal vein blood and in duodenal mucosa biopsies in stressed male Wistar rats as compared to control animals. The stressed animals showd a significantly higher scretin content of the duodenalmucosa and no different levels of the portal vein blood. A stress ulcer-reducing cimetidine application does not demonstrate any influence of secretin content on duodenal mucosa. The obvious elevation of duodenal secrtin is not the result of an increased gastric acid production, but may be a consequence of a stress-reduced susceptibility of the pancreas to endogenous secretin.
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