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Biomedical subjects

J Constans

Publications and source records attributed to J Constans.

At least 73 records · Page 4Linked to original sources

Alteration of arterial distensibility in systemic sclerosis.

OBJECTIVES: To evaluate the distensibility of large arteries in patients with systemic sclerosis (SSc). DESIGN: Prospective case-control study including unselected patients with SSc. SETTING: One cardiology and two internal medicine units in a teaching hospital. SUBJECTS: Eighteen patients with SSc and controls matched for age, sex, height, weight and 24-h ambulatory blood pressure (BP). INTERVENTION: The timing of Korotkoff's sounds (QKD interval), a newly described noninvasive ambulatory method was used to measure arterial distensibility during 24 h. MAIN OUTCOME MEASURES: Two endpoints were used: QKD 100-60 (normalized for a heart rate of 100 beats min-1 and a systolic BP of 100 mmHg) and the slope of QKD against pulse pressure. RESULTS: The patients with SSc had a lower slope of QKD against pulse pressure than the controls (median 0.55, range 0-1.21, versus 0.92, range 0.5-1.34, respectively; P = 0.003), and a lower QKD 100-60 (medians/ranges respectively 191 [162-216] and 203 [169-231]: P = 0.01). CONCLUSIONS: These results indicate that arterial distensibility of large arteries is decreased in SSc.

Adult↗

Soluble adhesion molecules and endothelial cell damage in HIV infected patients.

Endothelial damage is present in HIV infection but our understanding of markers and mechanisms is incomplete. We found increased levels of markers of endothelial cell damage such as von Willebrand factor (vWf), soluble thrombomodulin (sTM) and adhesion molecule E-selectin in 90 subjects seropositive for HIV relative to healthy controls. sTM was strongly raised in those patients with the lowest CD4+ cell count (p < 0.001), but levels of vWf increased at each incremental fall in CD4+ cell count and the two indices correlated significantly (r = -0.485, p < 0.001). vWf correlated strongly with levels of the inflammatory cytokines tumor necrosis factor (TNF-alpha) and alpha interferon (IFN-alpha) but sTM correlated only weakly with IFN-alpha. We suggest that increased vWf is largely the result of inflammatory stimulus of the endothelium but that sTM is found only in those patients with more severe disease, and so truly represents endothelial damage.

Adolescent↗

Up-regulation of tissue factor expression by platelet-derived growth factor in human vascular smooth muscle cells in culture--role of mitogen-activated protein kinase and effects of intracellular cyclic AMP.

Human vascular smooth muscle cells (SMCs) isolated from normal adult arteries were investigated for the expression of Tissue Factor (TF) procoagulant activity at their membrane surface and TF antigen in lysed cells. In growing conditions, SMCs expressed high levels of TF activity and antigen. When cells were made quiescent by 72 h of subculture in serum-poor medium, these levels fell to about one third of the initial values. Platelet-derived growth factor BB (PDGF) up-regulated in a dose-dependent manner TF expression with a significant increase (1.8 fold) within five hours. PD 98059, a specific inhibitor of mitogen-activated protein kinase (MAPK) pathway involved in cell response to PDGF, also prevented TF up-regulation. Short-term treatment by Pentoxifylline and dibutyryl cAMP also completely prevented induced TF up-regulation, but remained without effect on baseline levels of quiescent, unstimulated cells. At their effective concentrations, pentoxifylline and dibutyryl cAMP also inhibited the activation of MAPK induced by PDGF. The rapid induction of TF upon growth factor stimulation may be important in circumstances where SMCs proliferate, such as vascular events or vessel development.

Adult↗

[Kikuchi-Fujimoto necrotizing histiocytic lymphadenitis: apropos of 2 cases and review of the literature].

The Kikuchi-Fujimoto's syndrome is an histiocytic necrotizing lymphadenitis which is observed at any ages but preferentially among young adults. The sex ratio is about 4:1 in favour of women. It is clinically characterized by cervical lymph nodes in a context of fever and asthenia. Sometimes, there is transitory leucopenia and an increase of the erythrocyte sedimentation rate. The course of the disease is spontaneously favourable in 1 or 3 months but recurrence is possible. The histology of the lymph node could mimic a malignant lymphoma and the immunohistochemical findings are of a great importance (Ki-M1P or KP1 antibody). The etiology remains unknown but some infectious diseases have been suspected (toxoplamosis, Epstein-Barr virus). Its association with a systemic lupus erythematous had been described and this set the problem of its physiopathology. We report two new cases of Kikuchi-Fujimoto's syndrome which one was attributed to Epstein-Barr virus primo-infection and the other associated with a systemic lupus erythematous.

Adult↗

[Thrombosis of the superior mesenteric artery and Behçet's syndrome].

The authors describe the third case in the literature of superior mesenteric artery's thrombosis occurring in the course of the Behçet's syndrome according to Mason and Barnes classification. Clinical manifestations in the patient were represented by intestinal angor. The literature data concerning vascular involvement in Behçet's disease, particularly thrombosis are reviewed. The value of noninvasive paraclinic arterial digestive explorations is discussed.

Adult↗

The enzymatic antioxidant system in blood and glutathione status in human immunodeficiency virus (HIV)-infected patients: effects of supplementation with selenium or beta-carotene.

To investigate the effects of selenium or beta-carotene supplementation in human immunodeficiency virus (HIV)-infected patients, who are known to have deficiencies of selenium and vitamin A, we evaluated the blood enzymatic antioxidant system, including superoxide dismutase (SOD), selenodependent glutathione peroxidase (GPX), and catalase (Cat); glutathione (GSH) status; and plasma selenium concentration. The placebo group consisted of 18 HIV-infected patients with no supplementation, the selenium group was composed of 14 patients receiving oral selenium treatment, and the beta-carotene group comprised 13 patients receiving oral beta-carotene supplementation. All groups were studied for 1 y. At the beginning of the study, a significantly higher SOD activity (P < 0.001) was observed in all HIV-infected patients compared with uninfected control subjects, and GPX activity at baseline was higher in the placebo (P < 0.004) and selenium (P < 0.014) groups than in the control subjects. These higher enzyme activities could be related to an increased synthesis of these enzymes in erythrocyte precursors under oxidative stress. Moreover, we observed significantly lower GSH values in all HIV-infected patients than in control subjects at the beginning of the study (P < 0.001). After selenium or beta-carotene supplementation, no significant difference was observed for SOD activity compared with baseline. On the contrary, GPX activity increased significantly after selenium treatment (P < 0.04 between 3 and 6 mo), whereas a slight increase was found after beta-carotene treatment. Similarly, a significant increase in GSH values was observed at 12 mo compared with baseline both after selenium supplementation (P < 0.001) and beta-carotene supplementation (P < 0.01). Because GPX and GSH play an important role in the natural enzymatic defense system in detoxifying hydrogen peroxide in water, selenium supplementation could be of great interest in protecting cells against oxidative stress. The lower efficiency of beta-carotene could be attributed to the seriousness of the pathology at the time of recruitment into the beta-carotene group.

Acquired Immunodeficiency Syndrome↗

Increases in CD3+CD4-CD8- T lymphocytes in AIDS patients with disseminated Mycobacterium avium-intracellulare complex infection.

Human immunodeficiency virus type 1 (HIV-1)-infected persons frequently have increased numbers of T cells bearing the gamma delta T cell receptor for antigen (gamma delta TCR). HIV-1-seropositive patients with < 100 CD4+ cells/mm3 were selected and divided into 9 AIDS-defining illness groups. The percentages of CD4+, CD8+, or double-negative CD4-CD8- (DN) T cells (most of the latter expressing the gamma delta TCR) for 8 symptomatic groups were compared with those for a reference group of asymptomatic HIV-1-infected patients. DN T cells were increased only in patients with disseminated Mycobacterium avium-intracellulare complex (MAC) infection, toxoplasmosis, or Kaposi's sarcoma. Multivariate logistic regression analysis revealed that the percentage of DN T cells was a better predictor of MAC infection than was the percentage of CD4+T cells. The increased percentage of DN T cells might have important implications for the understanding of gamma delta T cell physiology and for the early diagnosis and management of MAC infections in AIDS patients.

AIDS-Related Opportunistic Infections↗

Lipoprotein(a) in 505 hospitalized patients with various pathological states: correlations with cardiovascular diseases and therapies.

OBJECTIVE: Our aim was to study the lipoprotein (a) (Lp(a)) levels in various pathological states. EXPERIMENTAL DESIGN: This investigation was prospective and included a healthy control group. SETTING: This study was carried out in two internal medicine and angiology services in teaching hospitals. PATIENTS: 505 patients were included with various diseases: 66 acute infections, 9 HIV infections, 25 cancers, 86 diabetes, 36 systemic diseases, 94 atheromatous vascular disease, 27 arterial hypertensions. A control group was composed of 21 healthy subjects. INTERVENTIONS: There was no therapeutic intervention but cardiovascular treatments were recorded. MEASURES: Serum Lp(a), total cholesterol, triglycerides, HDL-cholesterol, calculated LDL-cholesterol, apolipoproteins A-I and B were measured together with inflammatory parameters, serum creatinine, proteinuria, serum aminotransferase activity. RESULTS: There was no difference in Lp(a) levels between controls and each patient group. However, a correlation was found in systemic diseases between Lp(a) and C reactive protein (r = 0.371, p = 0.026) or serum albumin concentration (r = 0.453, p = 0.006). In hypertension, Lp(a) correlated with serum creatinine (r = 0.420, p = 0.03). In the whole patient population, Lp(a) was correlated with cholesterol (r = 0.156, p = 0.0001), apolipoprotein B (r = 0.215, p = 0.0001), age (r = 0.108, p = 0.015), arterial events (r = 0.174, p = 0.0001) and platelet anti-aggregant drugs (r = 0.169, p = 0.0001). CONCLUSIONS: Lp(a), was related to atheromatous events and in systemic diseases to inflammation, suggesting that Lp(a) might vary in some patients in a manner similar to acute phase proteins.

Adult↗

Treatment of mixed cryoglobulinemia with recombinant interferon alpha and adjuvant therapies. A prospective study on 20 patients.

In order to evaluate the efficacy of interferon alpha (IFNa) in mixed cryoglobulinemia (MC), a prospective multicenter clinical trial was conduced in April 1992. It consisted of treating 20 clinically symptomatic MC patients with IFNa for 26 weeks. Hepatitis C virus (HCV) infection was detected in 16 patients. A complete or partial clinical remission was obtained in 12 patients (60%). Eleven of these 12 responders (91.6%) experienced a clinical relapse less than 12 months after the end of therapy. Side effects were noted in 10 patients (50%). It was concluded that subcutaneously administered IFNa does not provide long-term remission.

Adrenal Cortex Hormones↗

New rare variants and interpretation of the genetic diversity at the group-specific component (GC) locus in populations of India.

As part of our ongoing genetic studies, 2635 samples from 30 populations of the Indian subcontinent have been analyzed for GC subtype variation. Several rare variants were found and have been characterized using isoelectric focusing in 3 M urea and with an immobilized pH gradient and by comparison with known standards. Six new variants, 1A33, 2A22, 2A23, 2A24, 1C56, and 1C59, have been discovered in geographically and ethnically distant populations of the Indian subcontinent. Variants 1C11 and 1C21 have been reported previously in the French population and variant 1C36 has been reported in Nepalis, but all three variants were observed for the first time in the populations of India. The distribution of the rare variants in the Indian subcontinent was examined for anthropological usefulness for differentiation of Indian populations. The data for GC allele frequencies from 144 populations of India were compared for geographic and ethnic variation. A high frequency of the GC*IF allele was observed in populations of eastern India, and various ethnic groups from the eastern zone were clearly differentiated from similar ethnic populations from the rest of India. GC*2 allele frequency data were further correlated with various geographic and climatic variables, such as longitude, latitude, sunshine, solar radiation, and mean annual temperature. A significant positive correlation between GC*2 frequency and latitude was observed. The GC*2 allele frequency showed a cline increasing from south to north. Significant negative correlation was also observed between GC*2 frequency and sunshine, solar radiation, and mean temperature. A possible interpretation for selection of the GC*2 allele in areas with low levels of insolation is provided.

Climate↗

Fatty acids and plasma antioxidants in HIV-positive patients: correlation with nutritional and immunological status.

OBJECTIVE: To investigate red blood cell (RBC) and plasma fatty acids (FA) in HIV-positive patients in relation to oxidative stress and nutritional or immunological status. DESIGN AND METHODS: FA, plasma selenium, vitamins A and E were measured in 95 patients divided into four groups according to CD4 cells. RESULTS: Poly- and di-unsaturated FA (PUFA, DUFA) decreased and saturated FA (SFA) increased in RBC in the patients below 400/mm3 and in plasma in the patients below 50/mm3. RBC SFA correlated to CD4 cells, PUFA to MDA. Unlike vitamin E, plasma vitamin A and selenium decreased in most groups. Plasma SFA and MUFA correlated negatively to selenium and PUFA and DUFA to vitamin E. No correlation was found between PUFA and nutritional markers. CONCLUSION: FA seem to be modified during HIV infection by oxidative stress and disease evolution, but not by denutrition.

Adult↗

[Disseminated Mycobacterium avium complex infections in AIDS. Apropos of 100 cases. Groupe d'Epidémiologie clinique du SIDA en Aquitaine].

The improvement of survival of AIDS patients allowed the emergence of disseminated Mycobacterium avium Complex infections (D.MAC). Here we report the experience of the group of "Epidémiologie clinique du sida en Aquitaine (GECSA)" about 100 patients. There were no differences according to sex, age and route of acquisition of HIV. Clinical and biological characteristics of the infections were not specific. The mean TCD4+ lymphocytes count was 18/mm3. The diagnostic was generally established by systematic blood culture on Septi-Chek in patients with TCD4+ lymphocytes count below 75/mm3. The recommendations on therapy for D.MAC are to use regimen containing azithromycin or clarithromycin, ethambutol and one of the following drugs, rifabutin, clofazimine, amikacin, or ciprofloxacin. Rifabutin is recommended for prophylaxis in patients with lymphocytes TCD4+ count below 100/mm3.

AIDS-Related Opportunistic Infections↗