PubMed Health⌕ Search

Biomedical subjects

E David

Publications and source records attributed to E David.

At least 37 records · Page 2Linked to original sources
PubMed1990

Characterization of a receptor for human monocyte-derived neutrophil chemotactic factor/interleukin-8.

Monocyte-derived neutrophil chemotactic factor/interleukin-8 (MDNCF/IL-8) is an 8,000-dalton protein produced by monocytes which exhibits activity as a chemoattractant for neutrophils with maximal activity achieved at a concentration of 50 ng/ml. This polypeptide has been iodinated by chloramine-T methodology (350 Ci/mM), and specific receptors for MDNCF/IL-8 have been detected on human neutrophils, U937 cells, THP-1 cells, and dimethyl sulfoxide-differentiated HL-60 cells. The binding of MDNCF/IL-8 to human neutrophils is not inhibited by interleukin-1 alpha, tumor necrosis factor-alpha, insulin, or epidermal growth factor. In addition, chemoattractants such as C5a, fMet-Leu-Phe, leukotriene B4, and platelet-activating factor fail to inhibit binding, suggesting that MDNCF/IL-8 utilizes a unique receptor. The receptor for MDNCF/IL-8 is apparently glycosylated since ligand binding is inhibited by the presence of wheat germ agglutinin, a lectin with a binding specificity for N-acetylglucosamine and neuraminic acid. Steady state binding experiments indicate Kd values of 4 and 0.5 nM and receptor numbers of 75,000 and 7,400 for human neutrophils and differentiated HL-60 cells, respectively. 125I-MDNCF/IL-8 bound to human neutrophils is rapidly internalized and subsequently released from cells as trichloroacetic acid-soluble radioactivity. Affinity labeling experiments suggest that the human neutrophil MDNCF/IL-8 receptor exhibits a mass of approximately 58,000 daltons.

Affinity Labels↗
PubMed1990

The effect of Zollinger-Ellison syndrome and omeprazole therapy on gastric oxyntic endocrine cells.

In 1983, all trials of omeprazole in humans were stopped because rats given the drug developed gastric endocrine cell hyperplasia and carcinoid tumors. Further studies in rats showed that drug-induced achlorhydria and hypergastrinemia caused these changes. Because data in humans are limited, we compared the numbers of endocrine cells, as judged by silver staining (argyrophilia), in the gastric mucosa of patients with Zollinger-Ellison syndrome, who are hypergastrinemic, and in normogastrinemic patients with idiopathic acid-peptic diseases. In addition, we analyzed the number of gastric endocrine cells in patients with Zollinger-Ellison syndrome given omeprazole for up to 3 years. Patients with Zollinger-Ellison syndrome had 15.7% +/- 6.9% argyrophil cells in biopsies of gastric oxyntic mucosa, and patients with idiopathic acid-peptic disease had 7.8% +/- 2.3% (P less than 0.01). In patients with Zollinger-Ellison syndrome, the percentage of argyrophil cells was not related to serum gastrin concentration, duration of symptoms, time since diagnosis, basal or maximal acid output, extent of tumor, or age. There was a tendency for patients with multiple endocrine neoplasia type 1 to have a greater percent of argyrophil cells than patients with sporadic Zollinger-Ellison syndrome. Considering the biopsies from both normogastrinemic and hypergastrinemic patients, there was a significant relationship between the percentage of argyrophil cells and the serum concentration of gastrin (P less than 0.01). Patients with Zollinger-Ellison syndrome given omeprazole for up to 3 years developed no significant changes in percentage of argyrophil cells, no carcinoid tumors, and no changes in serum concentrations of gastrin. The present study shows that patients with Zollinger-Ellison syndrome have an increased percentage of argyrophil cells in oxyntic mucosa and that omeprazole does not increase this percentage. In periods of up to 3 years, omeprazole had no effects on gastric morphology in patients with Zollinger-Ellison syndrome.

Adult↗
PubMed1990

CMV enteritis causing hemorrhage and obstruction in an infant with AIDS.

Serious gastrointestinal infections from cytomegalovirus (CMV) are often observed in immunosuppressed patients especially those with acquired immunodeficiency syndrome (AIDS). Hemorrhage and perforation have been frequent consequences. We present a case of CMV enteritis in an infant with AIDS who suffered massive hemorrhage and subsequent fatal small bowel obstruction from this condition. Gross findings at laparotomy were striking, diffuse, large yellowish plaques along the entire length of the small bowel. Each of these had a central ulceration. Each eventually caused a partial narrowing resulting in refractory small bowel obstruction. Biopsy of one of these lesions demonstrated many cells with typical cytomegalic inclusion bodies. This report illustrates a newly recognized type of CMV enteritis that can affect an infant and be readily recognized at laparotomy.

Acquired Immunodeficiency Syndrome↗
PubMed1990

[Report on threatened premature labor: etiology, management, results].

The studies on the aetiological factors of a premature delivery constitute an old fear of obstetricians and epidemiologists. However, they remain confused and the very definition of prematurity is among the first sources of confusion. There are many therapeutic methods considered as preventive. Their efficacy is debatable whilst their secondary effects are obvious. In this article, the authors report the results of a retrospective study of observations of patients who presented threats of premature labour and analyzed the epidemiological aspects, the aetiological factors and the therapeutic methods. It seems important to consider the risk factors in order to prevent premature labour. A decrease in the use of betamimetics and an increase in that of therapies said to be of replacement does not seem to be accompanied by a relative increase in the incidence of prematurity.

Adult↗
PubMed1989

Natural course and response to interferon of chronic hepatitis B accompanied by antibody to hepatitis B e antigen.

The course of chronic hepatitis B was studied in 30 patients who had antibody to hepatitis e antigen and hepatitis B virus DNA in the serum and hepatitis B core antigen in the liver. Over a 2-year period, no patient experienced a sustained spontaneous remission of disease, and follow-up liver histology revealed worsening of the disease in four patients. After 2 years of observation, 24 patients were allocated randomly to one of two groups: 12 patients served as untreated controls and 12 received recombinant human alpha-interferon-2a in a dose of 9 million units intramuscularly three times weekly for 16 weeks. Patients who remained viremic after 16 weeks received 3 million units three times weekly for an additional 8 weeks. Abnormal amino-transferases and serum hepatitis B virus DNA persisted without appreciable changes in all untreated patients. Hepatitis B virus DNA rapidly became undetectable and serum aminotransferases fell to normal in eight treated patients. After the end of treatment, hepatitis B virus DNA became detectable once again in seven patients, in six of whom a peak of aminotransferases (range: 256 to 850 units per liter) ensued; subsequently, hepatitis B virus DNA disappeared, and serum aminotransferases again fell to normal in two of the seven. Overall, hepatitis B virus DNA was no longer detectable in serum and liver histology improved in three treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Psychosomatic correlations in chronic pain patients using electroacupuncture.

Different reports on the efficacy of electroacupuncture in pain led to a randomized prospective study on 120 patients suffering from long-term chronic pain syndromes of different aetiology taking into account the psychological situation. The collected data included measuring the pulse amplitude difference of the arteria radialis dextra and sinistra oscillographically, pain evaluation by visual analogue scales, blood pressure and heart frequency and psychometrie. Results show that neurotic patients have a higher level of anxiety and that reduction of pain and the equalization of the amplitudes of both arterial curves is higher in anxious patients. The results are highly significant with an alpha value of 0.001.

Acupuncture Therapy↗
PubMed1989

Localisation of auditory evoked potentials in man during awakeness and sleep.

Auditory evoked potentials after click, speech and musical stimulation during sleep and awakeness were used in order to determine the existence of a topographical dominance of single cortical areas. The results showed a lateralization in awake subjects dependent on the semantic content of the stimulus. During deep sleep the lateralization of the potential was absent and the activity was extremely symmetrically concentrated around the vertex. The findings support the concept of cerebral dominances which has to be more than a pure metaphorical one.

Acoustic Stimulation↗
PubMed1988

Generation of leukotrienes by antigen and calcium ionophore A23187 stimuli from a mouse mastocytoma cell line, MMC-16.

The generation of leukotrienes and histamine release by the mouse mastocytoma cell line MMC-16 was investigated. These cells produced leukotriene C4 (LTC4) and released histamine upon calcium ionophore A23187 and antigen stimulation. The ionophore also stimulated the biosynthesis of leukotriene B4 (LTB4) by MMC-16. Generation of LTC4 was confirmed by its characteristic UV absorption spectrum, fast atom bombardment-MS, equivalent HPLC retention time with an authentic standard and radioimmunoassay. Leukotriene B4 was characterized by its distinctive UV spectrum and HPLC retention time compared with synthetic material. IgE-mediated LTC4 generation was also observed in a dose dependent fashion with MMC-16 cells passively sensitized with monoclonal IgE specific for ovalbumin. LTC4 biosynthesis was effectively inhibited by the lipoxygenase inhibitor NDGA.

Animals↗
PubMed1988

Phosphorylation of brain specific membrane proteins of developing chick embryo.

Phosphorylation of plasma membrane proteins in various tissues of chick embryos was investigated during the development. A polypeptide of Mr 22,000 was found to be the major phosphorylated plasma membrane protein in embryonic brain; this protein was absent in embryonic muscle, liver, and gizzard tissues. Extraction of plasma membranes with Triton X-100 (1%) or Nonidet p40 (1%) or sodium deoxycholate (1%) resulted in the solubilization of most membrane proteins including the 22 KDa phosphoprotein suggesting that the 22 KDa protein is a membrane-bound protein. Maximum phosphorylation of the 22 KDa protein by [gamma-32P]ATP was observed at 0.01 mM Ca2+. Higher concentrations of Ca2+ (2.5 mM) inhibited the phosphorylation of the 22 KDa protein whereas 3.5 mM Mg2+ stimulated the phosphorylation.

Animals↗
PubMed1988

Age-dependent changes in the level of a 22 KDa plasma membrane phosphoprotein in developing chick embryo brain.

In vitro phosphorylation of brain proteins of developing chick embryos showed a drastic increase in the extent of phosphorylation of a 22 KDa protein from the fourteenth day reaching a peak at seventeenth day of development; the phosphorylation of the 22 KDa protein declined afterwards. Phosphoaminoacid analysis of the 22 KDa protein indicated serine residues as targets of phosphorylation. Isoelectric focusing followed by second dimensional SDS-PAGE indicated that the 22 KDa protein had a pI value of 4.5. Polymyxin B, an inhibitor of Ca2+ and phospholipid dependent protein kinases inhibited the phosphorylation of the 22 KDa protein.

Aging↗
PubMed1987

Colonoscopy in inflammatory bowel disease. Diagnostic accuracy and proposal of an endoscopic score.

Colonoscopy is used in the differential diagnosis of inflammatory bowel disease but its accuracy and the "weight" of the various endoscopic signs have not been assessed. In a prospective study 357 patients with 606 colonoscopies, in whom the endoscopic appearances were those of ulcerative colitis, Crohn's colitis, or indeterminate colitis, were followed-up for an average period of 22 mo. A final, definite, endoscopy-independent diagnosis was reached by means of autopsy, surgery, or histology on biopsy in 71% of patients. Accuracy of colonoscopy was 89%, with 4% errors and 7% indeterminate diagnoses. Errors were more frequent in severe inflammatory activity (9%). The most useful endoscopic features in this differential diagnosis were discontinuous involvement, anal lesions, and cobblestoning of mucosa for Crohn's disease, and erosions or microulcers and granularity for ulcerative colitis. After selecting the endoscopic features with best predictive value, an "endoscopic score" was calculated by means of "likelihood ratios."

Colitis, Ulcerative↗