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Biomedical subjects

M Antoine

Publications and source records attributed to M Antoine.

At least 127 records · Page 7Linked to original sources

Nature of pulmonary hypertension in congestive heart failure. Effects of cardiac transplantation.

Pulmonary hypertension associated with congestive heart failure carries a risk of right ventricular failure after cardiac transplantation. Few data, however, are available on the hemodynamic behavior of the pulmonary circulation in these patients. We therefore studied mean pulmonary artery pressure minus left atrial pressure (estimated by pulmonary artery occluded pressure) versus cardiac output relationships in 20 patients with congestive heart failure evaluated for orthotopic cardiac transplantation, and we repeated this study either within the first 3 days postoperatively (n = 10) or 1 month postoperatively (n = 11). Cardiac output was increased by physical exercise or (in the early postoperative period) by an infusion of dobutamine. Reversibility of pulmonary hypertension was tested by an infusion of prostaglandin E1. At preoperative evaluation, the extrapolated pressure intercept of pulmonary vascular pressure:flow plots was negative in 10 of the patients, suggesting active exercise-induced pulmonary vasoconstriction. In the other 10 patients, the extrapolated pressure intercept was positive, suggesting that an increased closing pressure contributed to pulmonary hypertension. However, transplantation was constantly associated with proportional decreases of pulmonary artery pressure and left atrial pressure. On the other hand, pulmonary vascular pressure:flow plots were displaced to equal or lower pressures and to higher flows by prostaglandin E1 before as well as after transplantation. We conclude that in patients with congestive heart failure evaluated for cardiac transplantation, an increased pulmonary venous pressure more than a reversible increase in closing pressure determines the severity of pulmonary hypertension.

Adolescent↗

Evidence that a non-steroidal factor from corpus luteum of pregnant sheep inhibits aromatase activity of ovarian follicles in vitro.

Porcine and ovine follicular tissues were used to investigate, in vitro, the effect of charcoal-treated aqueous extract from ovine corpora lutea of pregnancy on aromatase activity as determined by the conversion of [3H]testosterone to oestradiol by follicular walls and measurement of 3H2O release. Extract (500 micrograms protein) prepared from corpora lutea of day 112 of pregnancy but not extract (500 micrograms) prepared from ovine fetal cotyledonary tissue obtained at a similar time significantly decreased (P < 0.02) aromatase activity of pig follicles in the absence of FSH. These results demonstrate that a non-steroidal factor in the corpora lutea of late pregnancy directly inhibits aromatase activity. When the effects of different doses (300, 600 or 1200 micrograms) of luteal extract from corpora lutea of day 100 of pregnancy on aromatase activity of pig follicles were studied, the dose by treatment (presence or absence of FSH) interaction was not significant. Luteal extract dose at 300 micrograms did not affect aromatase activity but a significant decrease in activity occurred at 600 micrograms of luteal extract (600 versus 300 micrograms, P < 0.02). There was no further significant increase in the inhibitory effect with 1200 micrograms luteal extract. When the effects of 600 micrograms luteal extract from corpora lutea of days 15, 75 or 100 of pregnancy on aromatase activity of pig follicles were studied, a significant (P < 0.05) stage of pregnancy effect was detected, but the stage of pregnancy by treatment (presence or absence of FSH) interaction was not significant. No effect was noted with day 15 or day 75 luteal extract.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Primary malignant lymphoma of the uterine body. Apropos of a case and review of the literature].

We observed a case of primary malignant lymphoma located in the uterine body which was discovered fortuitously after hysterectomy in a 75-year-old patient who suffered from post-menopausal bleeding. Search for extension did not reveal extra-genital involvement. This localization is exceptional and only 7 cases have been reported in the literature. The most frequent histological type is diffuse large-cell lymphoma. Surgical treatment is indicated with possible secondary radiotherapy and/or chemotherapy depending on the clinical presentation.

Aged↗

Effects of serotonin on coronary arteries of cardiac transplant recipients.

Serotonin constricts coronary arteries with endothelial dysfunction. To detect early graft artery disease, the responses to intracoronary serotonin were studied 1 month (group A, 14 patients) and 1 year (group B, 13 patients) after orthotopic cardiac transplantation. No patient had evidence of rejection and all had angiographically normal coronary arteries. Serotonin in increasing doses (1, 10 and 20 micrograms/min for 2.5 minutes each) was infused into the coronary circulation. Diameters of proximal, middle and distal segments were measured by quantitative angiography. At the maximal concentration of serotonin, the diameters of the proximal segments decreased to 73 +/- 4% (percentage of the baseline) in group A; the diameters of the middle and distal segments decreased to 67 +/- 5 and 63 +/- 4%, whereas in group B, the diameters of the proximal, middle and distal segments were 90 +/- 6% (p < 0.02 vs group A value), 88 +/- 5% (p < 0.01 vs group A value) and 84 +/- 4% (p < 0.01 vs group A value), respectively. These changes were significantly (p < 0.02) different from those observed in 6 control patients in whom no constriction was induced by intracoronary serotonin. Moreover, coronary plasma endothelin levels were significantly higher in group A than in group B and control patients (5.6 +/- 0.3 vs 4.3 +/- 0.2 fmol/ml in group B and 3.9 +/- 0.3 fmol/ml in control patients). Thus, an abnormal response to intracoronary serotonin seems to occur often in transplant patients, and this abnormality is unexpectedly more pronounced in the early weeks after transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

Severe hemolysis due to a donor anti-D antibody after heart-lung transplantation. Association with lung and blood chimerism.

Hemolysis due to donor-derived red cell antibodies is a potential complication after minor ABO-mismatched solid organ transplantation. It has also been described in Rh-positive recipients receiving organs from previously isoimmunized Rh-negative donors. We report on a group O, Rh(D)-positive patient who received a heart-lung transplant from a group O, Rh(D)-negative donor presenting an anti-D antibody. Severe hemolytic anemia developed in the early postoperative period and lasted for 3 mo. Anti-D antibodies that were of donor origin were found in bronchoalveolar lavage fluid and serum. In addition, using the polymerase chain reaction for human leukocyte antigen class II genotyping, we were able to demonstrate the presence of a mixed population of donor and recipient cells in the lungs and the peripheral blood of the recipient. The chimeric state in the blood persisted until at least the fifty-seventh postoperative day. This first case report of hemolysis due to Rh(D) antibody after heart-lung transplantation emphasizes the need for routine red cell antibody screening of donors and for close monitoring of signs of red cell destruction in the recipient in cases of pretransplant donor isoimmunization.

Adult↗

Dextroposition of the left lower lobe after heart-lung transplantation.

Immediately after heart-lung transplantation for cystic fibrosis, a patient had development of a right lower lobe retrocardiac density that persisted on all postoperative chest radiographs. A computed tomographic examination of the thorax performed 3 weeks after surgery showed that there was partial collapse of the left lower lobe in the right hemithorax. The patient required a posterolateral thoracotomy for cure.

Adult↗

Radiation-induced pulmonary veno-occlusive disease.

Late occurrence of radiation-induced pulmonary pneumonitis and fibrosis is well documented. We report an unusual case of radiation induced veno-occlusive disease (VOD) occurring six years following mantle irradiation for Hodgkin's lymphoma. The patient developed severe pulmonary hypertension and cor pulmonale. A left lung transplantation was performed successfully and pathologic examination of the explanted lung showed severe changes compatible with VOD. In the absence of exposure to alternate therapeutic or toxic agents that may cause VOD, it is likely that radiation caused damage to the venular endothelium and caused progressive obliteration of the pulmonary vessels. Review of the literature reveals only a few similar reports of VOD mostly following radiation for bone marrow transplantation. We conclude that previous irradiation (even several years earlier) should be considered as a possible cause of pulmonary VOD.

Adult↗

[Tubal bilharziasis].

We report a case of tubular bilharziosis discovered on a surgical specimen after salpingectomy. Tubular bilharziosis is not exceptional in endemic zones but is rarely found in Europe. The species most often isolated is Schistosoma haematobium. Contamination occurs via vascular anastomoses between the bladder and the genital organs. Bilharziosis has been shown to be a cause of extra-uterine pregnancy although its effect on fertility is yet to be established.

Adult↗

Respiratory dysfunction in congestive heart failure: correction after heart transplantation.

Severe chronic congestive heart failure (CCHF) is known to induce a restrictive ventilatory defect, with a small decrease in lung transfer factor for carbon monoxide (TLCO). The aim of the present work was to assess the reversibility of this dysfunction. We studied a group of 47 patients with CCHF, before and one year after heart transplantation. The measurements included static and dynamic lung volumes, TLCO and cardiac function. On initial evaluation, vital capacity (VC), total lung capacity (TLC) and TLCO were reduced to 76, 79 and 64% of the predicted value (% pred), respectively. Forced expiratory volume in one second (FEV1) was decreased to 69% pred, with a FEV1/VC ratio below 0.70 in 13 out of 47 patients. One year after transplantation, cardiac function had markedly improved, as shown by a normalized left ventricular ejection fraction (from 18% preoperatively to 59% postoperatively), and mean pulmonary wedge pressure (from 26 to 12 mmHg). At this time, VC (94% pred) and TLC (98% pred) were within the normal range, whereas TLCO remained low (67% pred). The FEV1/VC ratio did not change, even in the subgroup with an initial low value. Smoking habits did contribute to the low TLCO and FEV1/VC ratio. In conclusion, respiratory dysfunction induced by CCHF is reversible, with the exception of the reduction in TLCO, which probably reflects permanent changes in the lung vasculature. CCHF does not induce an obstructive ventilatory pattern.

Female↗

The organization of the intron-containing human S6 ribosomal protein (rpS6) gene and determination of its location at chromosome 9p21.

The intron-containing gene encoding human ribosomal protein S6 (rpS6), the major phosphoprotein in the mammalian ribosome, has been cloned. Using a PCR based cloning strategy we have isolated the rpS6 intron-containing gene in the presence of its many processed pseudogenes and determined the DNA sequence of the entire gene and its upstream and downstream flanking regions. The human rpS6 gene is 3979 bp in length and comprises six exons. Despite lacking a consensus TATA box, primer extension analysis indicates that the start of transcription is located at a single C residue within an 11 bp oligopyrimidine tract. The first exon, which contains the ATG start codon, is 48 bp in length. The DNA sequence in the 5' region of the gene has features of a CpG-rich island. Using fluorescence in situ hybridization (FISH) analysis the position of the rpS6 gene has been sublocalized to human chromosome 9p21. The similarities and differences between rpS6 and other previously characterized ribosomal protein genes are discussed.

Base Sequence↗

[Pleurisy in HIV infected patients].

Thirty-seven records of pleural effusion of known cause which occurred in HIV-seropositive patients hospitalized at the Tenon hospital, Paris, between 1985 and 1990 were analyzed retrospectively and divided into two groups: group 1 (n = 21) made up of kaposian effusions, and group 2 (n = 16) of infectious effusions serving as control. Numerous features distinguished group 1 from group 2 pleural effusions: In group 1 the effusion occurred in patients with cutaneous Kaposi sarcoma in 20/21 cases (P less than 0.001), developed slowly (more than 10 days) in 20/21 patients (P less than 0.001), was associated with a specific fever in only 4/21 cases (P less than 0.001), was bilateral in 20/21 cases (P less than 0.001), was regularly associated with bilateral parenchymatous opacities (P less than 0.001) and was haemorrhagic in 18/21 patients (P less than 0.001). Thus, simple semeiological features are sufficient to predict the cause of pleural effusion occurring in HIV-seropositive patients and to guide the diagnostic approach.

Adult↗

Primary structure and expression of a chicken cDNA encoding a protein with zinc-finger motifs.

We report the cloning and sequence analysis of a chicken nearly full-length cDNA clone, cKr1, encoding a protein of 509 amino acids which contains ten 2Cys + 2His-type zinc-finger motifs arranged in two separate sets of five zinc fingers each. The cKr1 transcripts are detected in organs of the adult chicken, predominantly in the brain and lung. At day 4 of embryonic development strong cKr1 hybridization signals are found in the brain and neural tube, in the mesonephros and in the gut, respectively.

Alpharetrovirus↗

Activation of the simian virus 40 (SV40) genome abrogates sensitivity to AVP in a rabbit collecting tubule cell line by repressing membrane expression of AVP receptors.

To analyze the role of SV40 genome in the phenotypic alterations previously observed in SV40-transformed cell lines, we infected rabbit renal cortical cells with a temperature-sensitive SV40 mutant strain (tsA58) and compared the cell phenotypes at temperatures permissive (33 degrees C) and restrictive (39.5 degrees C) for SV40 genome expression. At both temperatures, the resulting cell line (RC.SVtsA58) expresses cytokeratin and uvomorulin, but epithelial differentiation is more elaborate at 39.5 degrees C as shown by the formation of a well-organized cuboidal monolayer with numerous tight junctions and desmosomes. Functional characteristics are also markedly influenced by the culture temperature: cells grown at 33 degrees C respond only to isoproterenol (ISO, 10(-6) M) by a sevenfold increase in cAMP cell content above basal values; in contrast, when transferred to 39.5 degrees C, they exhibit increased sensitivity to ISO (ISO/basal: 19.1) and a dramatic response to 10(-7) M dDarginine vasopressin (dDAVP/basal: 18.2, apparent Ka: 5 X 10(-9) M) which peaks 48 h after the temperature shift. The latter is associated with membrane expression of V2-type AVP receptors (approximately 50 fmol/10(6) cells) which are undetectable when SV40 genome is activated (33 degrees C). Clonal analysis, additivity studies, and desensitization experiments argue for the presence of a single cell type responsive to both AVP and ISO. The characteristics of the RC. SVtsA58 cell line at 39.5 degrees C (effector-stimulated cAMP profile, lack of expression of brush-border hydrolases and Tamm-Horsfall protein) suggest that it originates from the cortical collecting tubule, and probably from principal cells.

Animals↗