Biomedical subjects

M Hadi

Publications and source records attributed to M Hadi.

6 recordsLinked to original sources

PubMed1999

Y receptor-mediated induction of CD63 transcripts, a tetraspanin determined to be necessary for differentiation of the intestinal epithelial cell line, hBRIE 380i cells.

Peptide YY (PYY) and neuropeptide Y (NPY) are peptides that coordinate intestinal activities in response to luminal and neuronal signals. In this study, using the rat hybrid small intestinal epithelial cell line, hBRIE 380i cells, we demonstrated that PYY- and NPY-induced rearrangement of actin filaments may be in part through a Y1alpha and/or a nonneuronal Y2 receptor, which were cloned from both the intestinal mucosa and the hBRIE 380i cells. A number of PYY/NPY-responsive genes were also identified by subtractive hybridization of the hBRIE 380i cells in the presence or absence of a 6-h treatment with PYY. Several of these genes coded for proteins associated with the cell cytoskeleton or extracellular matrix. One of these proteins was the transmembrane-4 superfamily protein CD63, previously shown to associate with beta(1)-integrin and implicated in cell adhesion. CD63 immunoreactivity, using antibody to the extracellular domain, was highest in the differentiated cell clusters of the hBRIE 380i cells. The hBRIE 380i cells transfected with antisense CD63 cDNA lost these differentiated clusters. These studies suggest a new role for NPY and PYY in modulating differentiation through cytoskeletal associated proteins.

Animals↗

PubMed1999

[Cerebral miliary granulomatosis with Histoplasma capsulatum in an HIV seronegative patient].

A 51 year old patient who worked in Africa for eight years, presented twelve years later a progressive ataxia associated with headaches. Neuroimaging studies done after a partial complex seizure demonstrated multiple supra and sub-tentorial cortical ring enhancing lesions. Histoplasma capsulatum histoplasmosis was found on histological examination of brain biopsy and confirmed by isolation of the fungus. Medical treatment with intravenous amphotericin B followed by oral itraconazole (400 mg per day) improved both clinical and radiological status. This observation of cerebral histoplasmosis is rather unusual for a seronegative HIV patient in a non endemic area.

Amphotericin B↗

PubMed1998

Molybdate binding by ModA, the periplasmic component of the Escherichia coli mod molybdate transport system.

ModA, the periplasmic-binding protein of the Escherichia coli mod transport system was overexpressed and purified. Binding of molybdate and tungstate to ModA was found to modify the UV absorption and fluorescence emission spectra of the protein. Titration of these changes showed that ModA binds molybdate and tungstate in a 1:1 molar ratio. ModA showed an intrinsic fluorescence emission spectrum attributable to its three tryptophanyl residues. Molybdate binding caused a conformational change in the protein characterized by: (i) a shift of tryptophanyl groups to a more hydrophobic environment; (ii) a quenching (at pH 5.0) or enhancement (at pH 7.8) of fluorescence; and (iii) a higher availability of tryptophanyl groups to the polar quencher acrylamide. The tight binding of molybdate did not allow an accurate estimation of the binding constants by these indirect methods. An isotopic binding method with 99MoO42- was used for accurate determination of KD (20 nM) and stoichiometry (1:1 molar ratio). ModA bound tungstate with approximately the same affinity, but did not bind sulfate or phosphate. These KDs are 150- to 250-fold lower than those previously reported, and compatible with the high molybdate transport affinity of the mod system. The affinity of ModA for molybdate was also determined in vivo and found to be similar to that determined in vitro.

Bacterial Proteins↗

PubMed1990

Effect of albumin on net copper accumulation by fibroblasts and hepatocytes.

The liver accumulates copper rapidly and preferentially from plasma. The effects of albumin on net copper accumulation by fibroblasts and hepatocytes were compared to determine whether preferential uptake involves hepatocyte-specific sequestering of copper. Although albumin inhibits the initial rates (30 s) of copper transport by fibroblasts and hepatocytes similarly, the effects of albumin on net copper accumulation (4 h) by these cell types were strikingly different. Fibroblasts accumulate only approximately 15% as much copper when equimolar albumin is present as from albumin-free media; hepatocytes accumulate about the same amount of copper with or without extracellular albumin present. Copper efflux data show that the special capacity of hepatocytes to accumulate copper in the presence of extracellular albumin is due to greater copper retention by hepatocytes than fibroblasts. The ability of hepatocytes to accumulate copper does not seem to be due to albumin-receptor-mediated uptake, since albumin was not co-transported with copper. The data are consistent with an equilibrium model of copper accumulation in which intracellular and extracellular copper are in equilibrium with intracellular and extracellular ligands. A high-affinity, copper-binding fraction that was previously identified in cytosols from hepatocytes was low or absent in fibroblasts. This may contain a liver-specific protein(s) that helps hepatocytes sequester and retain copper from albumin or serum-containing media. Irrespective of the exact species involved, the data are consistent with rapid, preferential copper uptake by the liver being due in part to a liver-specific, intracellular copper-binding protein(s) with a high binding affinity for copper.

Animals↗

PubMed1989

[Neonatal mortality at the Ille-et-Vilaine department. Results in 1987].

All 56 neonatal deaths that occurred during 1987 in Ille-et-Vilaine department (France) were systematically analysed, and the history of pregnancy, delivery, neonatal resuscitation, circumstances under which death occurred in neonatal care unit as well as autopsy findings were studied. Each case was then discussed by a multidisciplinary staff and consensus was obtained regarding diagnosis and cause of death. There were 2 separate categories: 26 deaths (46%) were due to related to malformation, or to metabolic dysfunction; 30 deaths were a result of other causes (54%): 9 low birth weight, 5 respiratory disorders, 5 neurologic disorders, 6 infectious diseases, 2 hemorrhagic shock and 3 were of unknown etiology. Information on causes of neonatal death in a specific region may aid in determining public health priorities for that region; if similar studies were carried out in each department, and results compared, this could aid in setting the guidelines for more efficient health treatments and lead to national choices about neonatal public health.

France↗

PubMedDate not supplied

Has fine-needle aspiration biopsy changed thyroid practice?

OBJECTIVE: To assess the influence of fine-needle aspiration (FNA) biopsy on the management of nodular thyroid disease. METHODS: We retrospectively evaluated the effect of the availability of FNA biopsy on thyroid surgical practice at our institution by comparing the data for two study periods--1975-1976 (before the introduction of FNA) and 1985-1986 (5 years after its introduction). RESULTS: The study inclusion criteria were fulfilled by 1,451 patients. In 1975-1976, 938 patients had thyroid operations at our institution. FNA biopsy was introduced into our practice in 1980. In 1985-1986, 513 patients underwent a thyroid surgical procedure. Before the FNA era, the frequency of carcinoma in patients selected for thyroidectomy was 18%, whereas after FNA became available, it increased to 25% (P< 0.0001). When patients were selected for surgical treatment because of either "suspicious" or malignant cytologic results, the yield of carcinoma increased to 40%. CONCLUSION: These data suggest that FNA biopsy has improved selectivity for operation in patients with nodular thyroid disease and has reduced the number of patients who undergo thyroidectomy for benign disease. The result is an increasing yield of malignant lesions found at surgical intervention. FNA biopsy has had a substantial cost-saving effect on thyroid practice.

Journal Article↗