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M Rais

Publications and source records attributed to M Rais.

34 records · Page 2Linked to original sources

[Progress in the diagnosis of unknown primary neoplasms].

About 5% of tumours clinically begin as unknown origin metastases involving some difficult diagnostic and therapeutic problems. In these cases the main goal is the formulation of the diagnosis as rapidly as possible because only about 10-15% of diagnosed patients are susceptible of treatment. Between 1973-1989 we observed 59 patients with unknown origin metastases. The diagnosis has been expressed in 5 patients by means of histochemical and immunohistochemical analysis, in 6 patients by means of radiologic and instrumental tests and in 3 patients spontaneously after 2-3 months.

Adenocarcinoma↗

A vivid model of chiral recognition.

Hands can be used to demonstrate the three-point model of chiral recognition. The points of attachment are thumb, forefinger, and middle finger. This vivid model has the advantages of simplicity, perspicuity, and availability at any time, although two persons are necessary. It can be shown that two interactions are not sufficient for chiral recognition but that three attractive or two attractive and one repulsive attraction are needed. It can also be used to explain some possibilities of weakening or elusion of the three-point model.

Hand↗

Determination of chloroquine and its desethyl metabolite in whole blood: an application for samples collected in capillary tubes and dried on filter paper.

A high performance liquid chromatography method for analysis of chloroquine and desethylchloroquine was adapted for 75 microliters aliquots of whole blood obtained by finger-prick and dried on filter paper. The precision of the method was satisfactory at whole blood concentrations of 40 nmol/L (coefficient of variation, 5%). The dried samples were stable for at least 7 weeks at 20 degrees C. The concentrations in venous whole blood and in dried samples correlated well. The correlation coefficient was 0.99 for chloroquine and 0.97 for desethylchloroquine. Chloroquine concentrations were marginally but significantly higher in venous whole blood. When fitted to a linear equation (y = bx + a) the relationship was y = 0.96x + 0.03. Desethylchloroquine concentrations did not differ significantly in venous whole blood and in finger-prick blood dried on filter paper. The method is specific and sensitive enough for pharmacokinetic studies and can be used in areas with limited technical facilities.

Blood Specimen Collection↗

Methyl-prednisolone treatment of serum HBsAg negative chronic active hepatitis occurring in transfusion-dependent thalassemia major.

We report the results of a two-year non randomized prednisolone trial carried out in 18 thalassemia major patients with chronic active hepatitis and in 16 controls. We found a beneficial effect on the biochemical remission rate and on the extent of liver inflammation with no significant side effects and no overt reactivation of possible latent HBV infection at three-year follow-up. However, a more prolonged longitudinal study is necessary in order to evaluate whether steroid treatment can impede the evolution to cirrhosis without determining long-term consequences, depending on virus-host interactions such as liver cell carcinoma.

Blood Transfusion↗

Chronic liver disease in transfusion-dependent thalassemia: liver iron quantitation and distribution.

The quantitative and/or qualitative distribution of liver iron was assessed in 81 transfusion-dependent thalassemia major patients with chronic liver disease (36 with chronic active hepatitis, 23 with chronic persistent hepatitis, 22 with siderosis). Viral marker studies showed only 3 cases with both HBsAg and anti-HBc positivity in the serum, while the others had anti-HBc and anti-HBs or only anti-HBs or no B viral markers. A significantly higher iron overload was found in chronic hepatitis, particularly chronic active hepatitis, than in siderosis. The increased iron overload may be due to less intensive chelation treatment, higher intestinal absorption secondary to lower mean Hb levels, and/or to liver inflammation-dependent iron deposition. The liver iron overload in turn amy facilitate the development or persistence of chronic progressive liver disease.

Adolescent↗

The sensibility of the hypophysis, the gonads and the thyroid of adolescents before and after the administration of oral contraceptives. A resume.

This research shows that the adenohypophysis of the adolescent differs from that of the adult by sensibility variations vis-a-vis of LHRH and TRF in relation to the growing rates of the ovarian steroids and their actions on the steroid and peptide receptors of the hypophyseal cells. During the first few years after the menarche, the increasing secretion of estradiol provokes a greater secretion of the four adenohypophyseal hormones both before and after LHRH and TRF. As the adolescent grows older, the increasing amounts of progesterone in relation to the increasing amounts of estradiol reduce the sensibility of the hypophysis to the releasing hormones; the release of its trophic hormones and prolactin is diminished. This would indicate that the hypothalamic-pituitary-ovarian system undergoes progressive maturation for a number of years after the menarche. The sensibility of the adolescent pituitary, ovary, and thyroid during the luteal phase of the first menstrual cycle after oral contraceptives have been discontinued is the same in girls who have taken oral contraceptives for 24 months or longer as it is in girls who are five to six years after the menarche and have not taken oral contraceptives.

Adolescent↗

Pentamidine concentrations in plasma, whole blood and cerebrospinal fluid during treatment of Trypanosoma gambiense infection in Côte d'Ivoire.

Pentamidine concentrations in plasma, whole blood and cerebrospinal fluid (CSF) were determined in 11 patients with Trypanosoma gambiense infection without involvement of the central nervous system in Côte d'Ivoire. Blood samples were drawn during a 48 h period after the first and last dose of pentamidine dimesylate given as 10 intramuscular injections on alternate days. Maximum plasma concentrations were generally attained within one hour after injection but varied extensively (420-13420 nmol/litre). The median plasma concentration 48 h after the last dose was approximately 5 times higher than that after the first dose. The ratio between whole blood and plasma concentration was approximately 2. Small amounts of the drug were found in the CSF after the last dose. The findings showed inter-individual differences in the pharmacokinetics of pentamidine. The currently recommended daily dose regimen could be questioned, as drug accumulation was pronounced. All patients were cured and the concentrations attained should be considered as parasiticidal. Further studies on the kinetics and distribution after single and multiple doses of pentamidine as well as studies on the possible relationship between adverse effects and plasma concentrations are, however, needed.

Adolescent↗

[Neuromuscular and vascular hamartoma of the small intestine. Report of a clinical case and review of the literature].

We present the case of a 50-year old patient, operated on for three adjoining annular strictures in the jejunum with proximal dilatation. He presented with a one-year history of recurrent cramping in the upper abdomen and vomiting, with two episodes of intestinal obstruction. Microscopic examination of the stricture revealed, in the submucosa, disorganised fascicles of smooth muscle derived from the muscularis mucosae, bundles of non-myelinated nerve fibres with scattered abnormal ganglion cells and haemangiomatous vessels. The pathological findings observed were similar to those described as neuromuscular and vascular hamartoma, a rare stricturing condition of the small intestine. Many authors have questioned the hamartomatous nature of this disorder, since identical features may be seen in Crohn's disease, in ischaemic enteritis, in radiation enteritis and in non-steroidal antiinflammatory drug-induced small intestinal strictures. On the basis of a review of the 5 previously described cases and of our own experience, we believe that neuro muscular and vascular hamartoma of the small bowel should be considered as a distinct entity if histological hallmarks of Crohn's disease are absent, in patients with no history of gastrointestinal disease, or of chronic ingestion of non-steroidal antiinflammatory drugs.

Hamartoma↗

Histopathological study of a case of systemic angiofollicular hyperplasia (Castleman's disease).

This report describes the nodal and hepatic lesions observed in a patient with generalized disorders that had been histologically diagnosed as a systemic angiofollicular hyperplasia. The diagnostic morphological findings were observed in the nodes of the axilla and were represented by diffuse marked plasmacytosis, prominence of the germinal centres, preservation of the architecture with a reactive proliferation of blood vessels and fibrous tissue in interfollicular areas.

Aged↗