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A Haddad

Publications and source records attributed to A Haddad.

At least 55 records · Page 3Linked to original sources
PubMed1999

Sokolow-Lyon voltage criteria in sickle cell patients.

The electrocardiogram remains the most commonly used method of cardiac assessment in developing countries. To determine the prevalence of electrocardiographic left ventricular hypertrophy (LVH) and the clinical significance of Sokolow-Lyon voltage criteria in sickle cell patients, echocardiographic and ECG findings were studied in 112 patients (71 with haemoglobin SS disease and 41 with haemoglobin SC disease). Electrocardiographic left ventricular hypertrophy (ECGLVH) defined as Sokolow-Lyon voltage > or = 35 mm was detected in 39 (55%) SS patients and 11 (27%) SC patients. This prevalence was higher in men than in women. There were statistically significant trends for increasing prevalence of ECGLVH with height (p < 0.007 in SS, and p < 0.01 in SC, patients) and with left ventricular internal dimension (p < 0.05 in SS, and p < 0.01 in SC, patients). But no significant trend was found with increasing posterior wall (PWT) or interventricular septal thickness (IVST). Sensitivity of Sokolow-Lyon criteria for detection of echocardiographic left ventricular hypertrophy was 63% and 33% in SS and SC patients, respectively, and specificity was 51% and 74%, respectively. Sokolow-Lyon voltage correlated with left ventricular mass in SS and SC patients (r = 0.44, p < 0.01 and r = 0.32, p < 0.05) and with left ventricular internal dimension (r = 0.2, p < 0.01 and r = 0.32, p < 0.05) but not significantly with PWT and IVST. We conclude that, in sickle cell patients, the electrocardiographic LVH mainly indicates the existence of an eccentric echocardiographic LVH with increase of left ventricular internal dimension.

Adolescent↗
PubMed1999

Total thyroidectomy is the recommended treatment for all Papillary Thyroid Carcinoma (PTC).

Surgical treatment of well differentiated carcinomas of the thyroid gland remains a discussed topic and there is still no evidence of global and total harmony in the appropriate surgical procedure to be applied in the approach of these tumors. The major unresolved debate concerning the ideal surgical management of PTC focuses on the extent of thyroidectomy. The most common recommended options range from thyroid lobectomy to a total extracapsular thyroidectomy. Controversy concern not only the extent of thyroidectomy but also the indications for, and the extent of cervical lymph node dissection. To date, there are no controlled prospective trials comparing the results of different surgical treatments of PTC. There are, however, several large retrospective reports that have addressed the extent of thyroidectomy in the management of patients with PCT1. The purpose of this review article is to demonstrate that total thyroidectomy seems to be the optimal treatment for most patients with clinically significant PTC. We also emphasize that the ability to perform thyroid surgery safely is of paramount importance with an excellent long-term prognosis. To determine the ideal treatment surgeons must weigh the risk-complications of a more aggressive surgical resection (total thyroidectomy) versus the risk of morbidity, mortality, recurrence rates and difficulty in following patients who undergo less gland resection (lobectomy). It is mandatory to expand efforts to identify high-risk patients more accurately, thereby facilating more rational approaches to treatment.

Carcinoma, Papillary↗
PubMed1998

Hyalocyte-like cells are more numerous in the posterior chamber than they are in the vitreous of the rabbit eye.

The distribution and concentration of free cells inside the eye chambers of rabbits were investigated using semi-quantitative analysis of histological paraffin sections. Studies using light (methacrylate sections) as well as transmission and scanning electron microscopy were undertaken for the morphological characterization of the free cells. Immunocytochemistry and autoradiography were employed in an attempt to find out their nature and their origin, respectively. It was observed that cells morphologically similar to the vitreous hyalocytes were more numerous inside the posterior chamber than were the hyalocytes in the cortical vitreous. Neither the hyalocytes nor the posterior-chamber cells reacted with an antibody to rabbit macrophages. The finding of labeled free cells after an intravitreal injection of 3H-thymidine indicates that these cells can renew themselves and that their number does not depend exclusively on monocytes migrating from the blood stream to the eye chambers, as is believed to occur. In conclusion, hyalocytes or hyalocyte-like cells are more concentrated in the posterior chamber than they are in the vitreous. Both the hyalocytes and the posterior-chamber cells could not be characterized as fully developed macrophages.

Animals↗
PubMed1998

Sulfation of intrinsic glycoproteins of the rabbit vitreous.

The experiments reported here were designed to characterize the intrinsic vitreous glycoproteins and to understand the process of their sulfation. Rabbits were injected intravitreally with 35S-sodium sulfate and killed at several time intervals after injection. In another series of experiments, rabbits were injected either with 35S-sodium sulfate, 3H-fucose or 3H-tyrosine, associated or not associated with tunicamycin administration. Vitreous from the control eyes was also digested with N-glycosidase. Furthermore, ciliary bodies, the putative source of the intrinsic vitreous glycoproteins, were incubated with 35S-sodium sulfate in the presence or absence of the protein synthesis inhibitor cycloheximide, and the culture media recovered for analysis. These and the vitreous samples of the other experiments were processed for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorography. Except for serum albumin, practically all polypeptide bands of the vitreous and culture media were labeled with radioactive sulfate and were shown to undergo renewal. The experiments using tunicamycin or enzyme treatment suggest that radioactive sulfate was incorporated not only into the carbohydrate side chains of the glycoproteins but also into the amino acid tyrosine of the polypeptide backbone of these glycoproteins.

Animals↗
PubMed1998

Increased production of a Th2 cytokine profile by activated whole blood cells from rheumatoid arthritis patients.

T cells produce regulatory cytokines which control inflammation. In rheumatoid arthritis (RA), a Th1 cytokine profile has been described in the synovium. In order to assess the Th1/Th2 cytokine balance in blood, a one step culture-immunoassay procedure was used to measure the ex vivo production of IFN gamma and IL-4 by whole blood cells from 26 RA patients and 25 controls. For comparison, the same cytokines were measured by ELISA in supernatants of activated whole blood cells. The direct whole blood assay was 10-fold more sensitive than standard ELISA to measure IL-4 levels. IL-4 production was higher in RA patients than in controls, whereas that of IFN gamma was lower. Accordingly, the IL-4/IFN gamma ratio, which reflects the Th2/Th1 cytokine balance in blood, was higher in RA patients (P < 0.0001). The present findings indicate a Th2-over-Th1 cytokine balance profile in RA blood. These results are in contrast with the Th1-over-Th2 pattern previously found in the joint, indicating that the two compartments appear to be differently regulated.

Adolescent↗
PubMed1998

Radioactive fucose as a tool for studying glycoprotein secretion.

The efficiency and reliability of radioactive fucose as a specific label for newly synthesized glycoproteins were investigated. Young adult male rabbits were injected intravitreally with [3H]-fucose, [3H]-galactose. [3H]-mannose, N-acetyl-[3H]-glucosamine or N-acetyl-[3H]-mannosamine, and killed 40 h after injection. In another series of experiments rabbits were injected with either [3H]-fucose or several tritiated amino acids and the specific activity of the vitreous proteins was determined. Vitreous samples were also processed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and histological sections of retina, ciliary body and lens (the eye components around the vitreous body) were processed for radioautography. The specific activity (counts per minute per microgram of protein) of the glycoproteins labeled with [3H]-fucose was always much higher than that of the proteins labeled with any of the other monosaccharides or any of the amino acids. There was a good correlation between the specific activity of the proteins labeled by any of the above precursors and the density of the vitreous protein bands detected by fluorography. This was also true for the silver grain density on the radioautographs of the histological sections of retina, ciliary body and lens. The contribution of radioautography (after [3H]-fucose administration) to the elucidation of the biogenesis of lysosomal and membrane glycoproteins and to the determination of the intracellular process of protein secretion was reviewed. Radioactive fucose is the precursor of choice for studying glycoprotein secretion because it is specific, efficient and practical for this purpose.

Animals↗
PubMed1998

Ethics in action.

Explore the source record for details and available documents.

Anti-HIV Agents↗
PubMed1998

The future of ethical decision making in health care.

As health care has become more complex in light of technological, economic, and organizational advances and changes, ethics has increasingly become a required component in decision making. This article examines four major trends: philosophical and practical problems with the place of ethics in health care, the necessity to broaden the focus of ethics committees, increase emphasis on interprofessional collaboration, and changes in the marketplace of health care delivery that will impact ethical decision making in the future.

Bioethics↗
PubMed1998

Transferrin production by the ciliary body of rabbits: a biochemical and immunocytochemical study.

PURPOSE: We have previously reported that transferrin is one of several glycoproteins synthesized within the eye and secreted into the vitreous. The present investigation was designed to determine the role of the ciliary body in the production of this vitreous transferrin. METHODS: Isolated ciliary body-iris were incubated with 3H-fucose, 3H-tyrosine or 35S-methionine and afterwards the culture media were processed for affinity chromatography using columns of Sepharose conjugated with antibody to rabbit plasma transferrin. Reverse transcription-polymerase chain reaction (RT-PCR) was carried out using total RNA extracted from fresh ciliary body-iris and primers constructed on the basis of the known sequence of transferrin mRNA from rabbit liver. The fragment obtained was employed as a probe in northern-blots of total RNA of ciliary body-iris. Furthermore, paraffin sections of eyes were treated for immunocytochemical visualization of transferrin. RESULTS: A labeled polypeptide, specifically eluted from the antitransferrin columns, was detected in the incubation medium, transferrin mRNA was found in extracts of whole ciliary body-iris, and transferrin antigenicity was identified in the ciliary and iridial epithelial cells by immunocytochemistry. CONCLUSIONS: These results demonstrate the ciliary epithelium as one of the sources of the vitreous transferrin.

Animals↗