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Biomedical subjects

M Lopez

Publications and source records attributed to M Lopez.

At least 433 records · Page 24Linked to original sources
PubMed1982

Cyproterone acetate in advanced male breast cancer.

Three male patients of 55, 63 and 71 years of age, with metastatic breast cancer, were treated with cyproterone acetate. Two patients showed complete remission, one lasting 21 months, another 51+ months and a third achieved partial remission lasting 9 months. These results suggest that cyproterone acetate may be useful in the treatment of advanced male breast cancer.

Aged↗
PubMed1982

Use of microcarriers to isolate and culture pulmonary microvascular endothelium.

Microcarriers of known diameter can be used to collect endothelial cells from microvessels of the same or slightly smaller internal diameter. The procedure is illustrated by collection of endothelial cells from rabbit pulmonary pre-capillary vessels. The lungs are perfused free of blood with physiological saline and then cold vessels. The lungs are perfused free of blood with physiological saline and then cold (4 degrees C) saline (containing EDTA, 0.02%, and microcarriers 600/ml; 40-60 micrometers diameter) is perfused via the pulmonary artery. The direction of flow is reversed periodically to collect the bead-cell harvest from the arterial side. Cold shock and EDTA cause the endothelial cells to detach from the vessels under conditions such that the cells remain attached to the microcarriers. The selective attachment to microcarriers is apparently aided by the tight fit of the beads within vessels of the same diameter. Beads do not emerge on the venous side, all being trapped at the pre-capillary level. Electron microscopic examination of lungs fixed during the perfusion shows that the beads lodge in terminal arterioles and pre-capillary vessels (approximately 40-60 micrometers in diameter, with one, sometimes incomplete, muscle layer). Endothelial cells recovered on microcarriers can be allowed to migrate on to flasks and back on to beads. The resultant cultures have an endothelial morphology and possess high levels of angiotensin coverting enzyme and carboxypeptidase N activity.

Animals↗
PubMed1982

B-cell acute lymphoid leukemia (ALL) with lymphoblasts expressing surface immunoglobulins only at relapse.

Morphological, cytogenetic and immunological studies were performed on lymphoblasts of two patients with acute lymphoid leukemia at onset and at relapse. At onset and before any treatment lymphoblasts had L3-FAB morphology, a 14q+ chromosome abnormality due to a 8;14 translocation in the absence of expression of specific immunologic markers (E-rosette, C3-receptor, surface immunoglobulins). The clinical behaviour of the two patients was characterized by a very short first complete remission and by a short survival. At relapse SIg was expressed by lymphoblasts of both patients. This evolution in immunological phenotype of the dominant blast populations from onset to relapse provides evidence that in vivo, during the course of the leukemic disease, phenotype changes take place that seem to be cell differentiation.

Adolescent↗
PubMed1982

Atypical transmission of ABO blood groups in a French family.

A group AB mother (Mrs P.D.) gave birth to a group O female baby (C.D.). Extensive study of the blood group genetic markers in both the parents and the child, carried out on several occasions, showed nothing unusual outside the ABO system. Mrs P.D. then, gave birth to a second female baby who was also group O. Mrs P.D. had normal amounts of A, B, H and Lewis antigens in her saliva. The H, A and B agglutinability of her red cells was in the range of normal A2B group. This A2B blood group was characterized by very low A gene-specified glycosyltransferase activity in serum. Moreover this activity was undetectable in red blood cell membranes. These results are discussed in the light of various hypotheses in order to explain this unusual transmission of ABO blood group.

ABO Blood-Group System↗
PubMed1982

Immunologic evaluation of T chronic lymphocyte leukemia cells: correlations among phenotype, functional activities, and morphology.

Chronic lymphocytic leukemia of T-cell origin (T-CLL), a rare variant of CLL, appears to be a clonal proliferation of mature T cells of one of several subsets. In the cells of 7 T-CLL patients, surface markers (including those reacting with a panel of monoclonal antibodies), functional activities, and electron microscopic morphology were evaluated. The phenotypic patterns of circulating T-CLL cells correspond to those of normal mature T-cell subsets. The cells of three patients demonstrated at least one marker reported to be expressed by suppressor/cytotoxic T cells: those of three patients expressed markers apparently linked with T-helper activity. Cells from one patient appeared to be a heterogeneous proliferation of more than one T-cell subset. These T-CLL cells may also retain some of the functional activity of the normal T subpopulations. Our data indicate that a combination of several tests should be used to characterize the proliferating cells in T-CLL.

Aged↗
PubMed1981

Mechanism for strand-break induction in DNA-proflavine complexes exposed to visible light.

Proflavine bound-superhelical phi XRFI DNA Molecules undergo single-strand scission upon irradiation with visible light at high fluence rate. As shown by agarose gel electrophoresis analyses, the nicking reaction is (i) oxygen-dependent, (ii) strongly inhibited by catalase and an electron scavenger such as cystamine, and (iii) totally suppressed by ceruloplasmin and radical scavengers such as t-butanol sodium benzoate. This indicates that H2O2, e-, O2 and OH, respectively, are involved in the cleavage process. NaN3, a singlet-oxygen quencher, has very little effect on strand-breakage but it prevents almost completely the alteration of guanine residues (a lesion already observed after irradiation at low fluence rate). Since, in the presence of NaN3, strand scission can occur and guanine (as the other bases) recovered intact, it follows that the radical intermediates produced during breakages are probably not involved in any permanent modification of the DNA bases.

Acridines↗
PubMed1981

[Effect of rheumatoid factors on results for determination of antitoxoplasms IgM antibodies by immunofluorescence and agglutination technics (author's transl)].

Simultaneous presence of antitoxoplasm IgG antibodies and of rheumatoid factors gives rise to an IgM-type immunofluorescence reaction in 44 p. cent of cases. Three experiments showed that association of the two antibodies can give rise to false positives in the Remington test ; the mixture of the two antibodies renders the reaction positive in the majority of cases. On the other hand, after absorption of negative rheumatoid factors and separation of serum IgM and IgG, IgM fluorescence is no longer seen ; if they are again mixed, then a positive reaction will result. Interference of antitoxoplasm IgG antibodies and rheumatoid factors does not occur in direct toxoplasm agglutination tests. The presence of the rheumatoid factor is rare in the pregnant female. Nevertheless, it is necessary to test for rheumatoid factors using the latex test. If results are here positive, then serum should be absorbed on aggregated human IgG and the Remington test repeated. The probably rare simultaneous presence of antitoxoplasm IgG antibodies and of rheumatoid factors cannot be differentiated from these false positives without fractionation of the serum, separating IgM and IgG.

Agglutination Tests↗
PubMed1980

Different H deficient phenotypes present in one kindred.

Two different H deficient phenotypes are observed in one kindred. Three of them in two generations of a same family appear as Bombay like. In the other branch of the kindred, an Hz phenotype (as described in the editorial of this issue) is observed. The most simple explanation is that the three Bombay like phenotypes correspond to Hz ABH non secretor (Hz sese) individuals, this being indistinguishable from a true Bombay. The high level of I antigen in the plasma of the three Bombay like (as observed in Hz in contrast to true Bombay) could favour such an hypothesis. According to ORIOL'S new hypothesis [5], III2, III3 and IV2 would genetically be hh sese, III8 would be hh Se and the h Se would therefore be a recombining haplotype (the original haplotype being h se).

ABO Blood-Group System↗