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Biomedical subjects

M Paul

Publications and source records attributed to M Paul.

At least 325 records · Page 18Linked to original sources
PubMed1991

Tissue-specific activation of cardiac angiotensin converting enzyme in experimental heart failure.

In addition to the circulating renin-angiotensin system, recent data demonstrate the existence of tissue renin-angiotensin systems that may be important in cardiovascular homeostasis. However, the relative activities of the circulating and tissue renin-angiotensin systems have not been examined previously in pathophysiological states, such as congestive heart failure. The present study was performed to examine the status of plasma and tissue angiotensin converting enzyme (ACE) activities in compensated experimental heart failure induced by coronary artery ligation in the rat. Three groups of male Sprague-Dawley rats were examined: 1) nonoperated rats (NO, n = 5), 2) sham-operated rats (SO, n = 5), and 3) heart failure rats (HF, n = 11). Rats were studied an averaged of 85 days postoperatively. In HF animals, plasma renin concentration and serum ACE activities were not different compared with NO and SO control animals. Cardiac ACE activity was 50% greater in the right ventricle than the interventricular septum in NO and SO rats. Both right ventricular and interventricular septal ACE activity increased approximately twofold in HF animals as compared with NO and SO groups (p less than 0.05). In contrast, pulmonary, aortic, and renal ACE activities were not altered in HF rats compared with control animals. A positive correlation existed between the histopathological size of myocardial infarction and the level of right ventricular ACE activity (r = 0.75, p less than or equal to 0.05). Such a relation between infarct size and either serum or noncardiac tissue ACE activities was not observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Tissue renin-angiotensin systems: fact or fiction?

The discovery of the components of the renin-angiotensin system (RAS) in various tissues gave rise to the idea that functional "tissue" RASs exist that are more or less independent of the hormonal RAS. Further support for this notion came from the recent demonstration of the mRNA for the protein components of the RAS in a number of organs. Last but not least, the introduction of the converting-enzyme (CE) inhibitors, generating an enormous scientific interest in the role of the RAS, has contributed to the concept of "tissue" RASs, since some of the effects of these drugs were thought to be reconciled better with "tissue" than with plasma RAS inhibition. However, this model of plasma vs. "tissue" RAS still suffers from a number of conceptual problems. For instance, with respect to the "tissue" RAS in the vascular wall, it is not clear at present whether angiotensin-converting enzyme (ACE) is at all active inside endothelial cells. In addition, all evidence available speaks against its localization in the vascular media, while there may be some activity of the enzyme in the adventitial layer. Concerning the heart, there is at present no unequivocal evidence for a local angiotensin II (Ang II) production through ACE in cardiac tissue outside the coronary vessels. The localization of Ang II generation within tissue RASs in the adrenal gland or in the kidney, where Ang II may be generated through CE at the tubular brush border, are far from being elucidated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Bone marrow culture for diagnosis of mycobacterial and fungal infections in febrile patients.

The perception and evaluation of patients with fever are constantly evolving. Due to sophisticated technology and financial constraints, increasing numbers of tests are performed earlier in patient evaluation. One is bone marrow culture for mycobacteria and fungi. To assess the yield of this procedure, we reviewed the results of cultures performed from 1982-1986 at Shands Hospital at the University of Florida. There were 124 patients so evaluated. No fungal cultures were positive. Four mycobacterial cultures were positive: three Mycobacterium avium-intracellulare, all in patients with AIDS (Acquired Immune Deficiency Syndrome), and one Mycobacterium tuberculosis in a patient with disseminated disease. Three patients ultimately found by other means to have disseminated mycobacterial infection were culture negative. We conclude that this procedure is of very low yield and only warranted in the patient with severe immunocompromise or the patient with strong clinical evidence of disseminated tuberculosis.

Adult↗
PubMed1991

[Vaginal sonography in the diagnosis of and therapeutic indications in cervical incompetence].

Besides its contribution to the diagnosis, the vaginal sonography or transvaginal ultrasound is a remarkable support in the indication of the treatment of cervical incompetence and its control after cerclage. The study group consisted of 40 patients, their gestational age between 16 and 29 weeks, admitted in the department for cervical incompetence. After transvaginal ultrasound examination combined to the results of clinical evaluations, 32 pregnant women were retained for cervical cerclage. The other cases were given only medical treatment. It springs out from the analyse of the criteria of exploration, the absence of a funnel shaped formation of internal os in the cases non retained for cervical cerclage at the vaginosonography examination. Likewise, but in a less degree (6/8) a cervical dilatation greater than or equal to 10 mm. The softening of the cervix was also absent in the majority of the cases (5/8) at the clinical examination. On the contrary, the cervix was shortened in all cases, both in clinical and ultrasound examination. Another important element is the advanced gestational age which is in favour of medical treatment and ultrasound check up. The average gestational age of the group without cerclage is 26.87 weeks and that of the whole study group is 23.64 weeks. The vaginalsonography makes possible the follow up, in the postoperative periods after cervical cerclage and the appreciation of the outline of internal os and the localisation of the band used for cerclage.

Evaluation Studies as Topic↗
PubMed1990

Cerebrospinal fluid neopterin in human immunodeficiency virus type 1 infection.

We evaluated cerebrospinal fluid (CSF) concentrations of neopterin, a putative marker of activated macrophages, in 97 subjects infected with human immunodeficiency virus type 1 who had a spectrum of neurological complications. The highest CSF neopterin concentrations occurred in those with neurological opportunistic infections, primary central nervous systems lymphoma, and acquired immunodeficiency syndrome (AIDS) dementia complex. In general, the CSF concentration of neopterin was independent of CSF cell count and blood-brain barrier disruption to albumin. In the patients with AIDS dementia complex, CSF neopterin concentrations correlated with severity of disease and decreased in conjunction with clinical improvement following treatment with zidovudine. These results suggest that CSF neopterin, although not disease-specific, may be useful as a surrogate marker for the presence of AIDS dementia complex and its response to antiviral therapy.

AIDS Dementia Complex↗
PubMed1990

Repair of complete atrioventricular septal defect with tetralogy of Fallot.

Repair of complete atrioventricular canal with tetralogy of Fallot was performed in 9 patients. Ventricular septal defect was closed through the right atrium using a single polytetrafluoroethylene patch with ample anterior extension to avoid subaortic obstruction. The atrial septal defect was closed with a separate patch. Undivided atrioventricular valve leaflets were sandwiched between the two patches. Right ventricular outflow tract stenosis was relieved by pulmonary valvotomy and an infundibular patch in 7, a supravalvar patch (none transannular) in 6, and right ventricle-to-pulmonary artery conduit in 2. There was one hospital death (1/9, 11%) in a patient with persistent clinically significant postoperative pulmonary stenosis and low cardiac output requiring reoperation and right ventricle-to-pulmonary artery conduit insertion. There was no late mortality. All patients are asymptomatic 0.3 to 5.6 years after operation. Follow-up right ventricular outflow tract gradient ranged from 11 to 43 mm Hg and was 70 mm Hg in 1 patient who later had successful relief of obstruction. Three patients had mitral valve insufficiency; 1 needed reoperation. Aggressive relief of right ventricular outflow tract stenosis with maintenance of pulmonary valve competence and use of two separate patches for closure of the septal defects contribute to optimum immediate and long-term results after repair of this lesion.

Abnormalities, Multiple↗
PubMed1990

Androgen dependence and tissue specificity of renin messenger RNA expression in mice.

Testosterone, a steroid hormone which increases blood pressure by hitherto unknown mechanisms, is known to induce renin synthesis in the submandibular gland (SMG) of mice. Since renin as well as all other components of the renin-angiotensin system are present in organs important for cardiovascular control, e.g. the kidney, heart, adrenal gland and brain, it is of interest to study the effect of testosterone on renin gene expression in these organs. Renin messenger (m) RNA concentrations were measured by a solution hybridization assay using a 32P-labeled mouse SMG renin complementary (c) RNA as a radioactive probe (detection limit: 1 pg renin mRNA). Measurements were performed after 2 h and after 2, 7, 14 and 21 days of dihydrotestosterone (DHT) treatment in female NMRI mice. Renin mRNA concentration (values are expressed as pg renin mRNA/ micrograms total RNA) in the SMG was significantly increased after 7 days (108 +/- 22 in controls versus 630 +/- 101 in DHT-treated mice), after 14 days (83 +/- 15 in controls versus 743 +/- 83 in DHT-treated mice) and after 21 days (107 +/- 30 in controls versus 579 +/- 76 in DHT-treated mice), but did not reach levels found in untreated male NMRI mice (1021 +/- 84). In the kidney, a decrease was observed within 21 days, from 43 +/- 4 and 40 +/- 4 to 29 +/- 2 and 22 +/- 1.7 pg/micrograms in controls and DHT-treated groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗
PubMed1990

[New valvular homografts. Prospects and limits of their viability. Report of 42 implantations].

The regain of interest in aortic homograft bioprostheses is related to the prospects of improved viability resulting from explanation from organ donors, preservation in rich tissue culture media, together with the progress made in techniques of cryopreservation. Viability studies examining morphology of electron microscopy and tests of tissue culture confirm this notion of longer viability. These properties raise hopes of satisfactory long-term results while acknowledging outstanding antigenic problems which require strict A-B-O system compatibility. The results of a preliminary series of 42 valve homografts implanted at Henri Mondor Hospital over the last 5 years are reported. Twenty-one bioprostheses were implanted on the right side in congenital heart disease with good results in every case. Twenty-one were implanted in the aortic position in children and show no signs of degeneration as yet. One poor result was related to a technical error in calibration. The rebirth of this technique raises certain hopes, especially in aortic valve replacement.

Adolescent↗
PubMed1990

[Viability of new valvular homografts. An evaluation at the Henri Mondor Hospital].

The renewed interest in valvular homograft is due to the new concept of their viability. This viability requires procurement from organ donors and preparation in rich tissue culture medium immediately prior to cryopreservation. This viability, confirmed by morphological tests especially electron microscopy, and by cell culture tests is the basis for satisfactory long-term results. Antigenic aspects justify rigorous respect of A-B-O compatibility. A preliminary clinical series of 35 valvular homografts (16 on the right side and 19 in the aortic position), implanted especially in children over the last five years at the Henri Mondor Hospital, is reported here, No tissue failures have been reported to date.

Aortic Valve↗
PubMed1990

Health, equity, and reproductive risks in the workplace.

Potential exposure to occupational reproductive hazards raises complex questions regarding health and gender discrimination in the workplace. On the one hand, growing scientific evidence suggests that workplace exposures to either sex can cause a wide range of disorders ranging from infertility to adverse pregnancy outcomes. On the other hand, policies alleging to protect workers from reproductive risks have often reinforced gender inequalities in the workplace. This article sheds new light on this continuing debate through an examination of the policy insights suggested by a recent study of reproductive hazard policies in Massachusetts. In what ways do policies evidenced in this study reflect or differ from historical patterns of protectionism? The article presents a political-legal review of reproductive hazard policies in the workplace, then examines the policy implications of the Massachusetts study, and finally presents the prescriptions for change that are implied by both the historical and contemporary evidence.

Female↗
PubMed1989

Corporate response to reproductive hazards in the workplace: results of the Family, Work, and Health Survey.

As a part of a Family, Work, and Health Survey, we analyzed corporate practices regarding reproductive hazards in the chemical and electronics manufacturing industries in Massachusetts. Over half of the 198 firms surveyed had at least one of four designated reproductive hazards in use. Among these firms, 57% provided information on reproductive risks to employees. Nearly 20% of companies excluded certain classes of workers from substances, work areas, or occupations on the basis of reproductive health concerns. Another 13% offered voluntary transfers to workers concerned about reproductive risks. With one exception, all restrictions and transfers applied to women only--even when scientific evidence supports potential reproductive risk to both sexes. Analysis of corporate practices by industry type, and size, gender stratification, and unionization of the workforce was carried out. Results of the survey raise important public health concerns about corporate practices that may restrict women's job opportunities on the basis of reproductive status while underprotecting the health of male workers.

Adolescent↗
PubMed1989

AIDS-related vacuolar myelopathy is not associated with coinfection by human T-lymphotropic virus type I.

Assessment of antibodies against human T-lymphotropic virus type I (HTLV-I) by enzyme-linked immunoassay, immunofluorescence, and Western blot was undertaken in patients with pathologically or clinically diagnosed acquired immunodeficiency syndrome-related vacuolar myelopathy to determine whether this retrovirus could be etiologically implicated in this disorder. No serological evidence for HTLV-I was found in the patients with vacuolar myelopathy, though 1 patient with an atypical myelopathy did have antibodies against HTLV-I.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Negative control elements and cAMP responsive sequences in the tissue-specific expression of mouse renin genes.

The 5' flanking regions of the mouse renin genes (Ren1d and Ren2d) contain putative negative control and cAMP responsive elements. Sequence analysis shows additionally that these putative control elements in the Ren2d gene are interrupted by a 160-base-pair insertion. To document the functions of these elements, we isolated these regions and fused them to the reporter gene chloramphenicol acetyltransferase (CAT), which was linked upstream to a thymidine kinase (TK) promoter (pUTKAT1). The chimeric constructs were transfected into mouse pituitary tumor AtT-20 and human choriocarcinoma JEG-3 cells. At the basal unstimulated condition, Ren1d 5' flanking sequence in the sense orientation inhibited basal CAT expression from the TK promoter of pUTKAT1, whereas the same sequence in the antisense orientation did not. The 5' flanking region of Ren2d had no inhibitory effect on basal CAT expression. These data demonstrate that the negative control element is functional in Ren1d but is nonfunctional in Ren2d, suggesting that the 160-base-pair insertion in Ren2d interferes with the function of the negative control elements. In response to 8-bromo-cAMP, both renin genes increased transcription 3-fold, suggesting a functional cis action of the cAMP responsive element in both genes. These data may be important in the understanding of the regulation of the tissue-specific expression of mouse renin genes.

8-Bromo Cyclic Adenosine Monophosphate↗