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Biomedical subjects

S Alvarez

Publications and source records attributed to S Alvarez.

At least 73 records · Page 4Linked to original sources

Localized soft-tissue infections with Mycobacterium avium/Mycobacterium intracellulare complex in immunocompetent patients: granulomatous tenosynovitis of the hand or wrist.

In immunocompetent patients, Mycobacterium avium/Mycobacterium intracellulare complex (MAC) has been associated with pulmonary infection in adults, cervical lymphadenitis in children, and disseminated infection in children and adults. MAC rarely has been recognized as a cause of localized soft-tissue infection in immunocompetent hosts. Six cases of granulomatous tenosynovitis due to MAC are reported; five cases occurred after local surgical procedures, trauma, or corticosteroid injection. In four cases, cure was achieved with combined medical and surgical intervention. In these six cases and 11 previously reported cases, both males and females were affected equally, usually in the fifth to seventh decades of life, and the distal upper extremity was predominantly involved. Surgical debridement with appropriate culture was critical for diagnosis and management. Antimycobacterial chemotherapy seemed to be a beneficial adjunctive measure in most cases but was clearly necessary for cure in only a few cases.

Aged↗

Vascular and other serious infections with Mycobacterium bovis after bacillus of Calmette-Guérin therapy for bladder cancer.

Intravesical application of bacillus of Calmette-Guérin (BCG) has proved to be an effective form of treatment for some stages of bladder cancer. Infrequent, serious complications of this treatment have become apparent as its use has become more widespread. We report a case of Mycobacterium bovis mycotic abdominal aortic aneurysm and a case of M. bovis mycobacteremia that developed as complications of intravesical BCG therapy. These cases are discussed in the context of a review of reported complications of intravesical BCG therapy and a review of measures currently advocated to prevent them.

Administration, Intravesical↗

Clinical comparison of the isolator and BacT/Alert aerobic blood culture systems.

The performance characteristics of the Isolator (Wampole Laboratories, Cranbury, N.J.) and the BacT/Alert (Organon Teknika Corporation, Durham, N.C.) aerobic blood culture systems were compared for 6,009 blood culture sets obtained from patients with suspected bloodstream infections. The BacT/Alert aerobic bottle [BTA(O2)] was continuously agitated while it was incubated in 5% CO2 at 36 degrees C; culture plates prepared from the Isolator tube [I(O2)] were incubated in 5% CO2 at 37 degrees C. From 394 blood cultures, 416 clinically significant isolates of bacteria and yeasts were recovered. The overall yields for BTA(O2) and I(O2) were not significantly different (319 versus 336; P = 0.20). I(O2) recovered significantly more staphylococcus (P < 0.05) and yeast isolates (P < 0.01). BTA(O2) recovered significantly more aerobic and facultatively anaerobic gram-negative bacilli (P < 0.05). In blood culture sets which produced growth of the same organisms in both the BTA(O2) and I(O2) systems, the BTA(O2) system detected growth sooner, but more rapid identification was possible with the I(O2) system by virtue of earlier isolation of colonies on solid media.

Bacteremia↗

Immune system stimulation by probiotics.

The immune system consists of organs and several cell types. Antigen interaction with these cells induces a cellular immune response mediated by activated cells and a humoral immune response mediated by antibodies. The cellular interactions are enhanced by adhesion molecules, and the activated cells release different cytokines. These complex cellular interactions induce a systemic immune response. If the antigen penetrates by the oral route, a secretory immune response is obtained, which is mediated by secretory IgA. The determination of the number of T or B cells, the quantitative or qualitative measure of the cytokines, antibody levels, or the study of cellular function such as phagocytic activity is used to evaluate the state of the immune system. The effects of lactic acid bacteria on the systemic immune response and on the secretory immune system are described. Potential health benefits of lactic acid bacteria include protection against enteric infections, use as an oral adjuvant, the immunopotentiator in malnutrition, and the prevention of chemically induced tumors. The results showed that Lactobacillus casei could prevent enteric infections and stimulate secretory IgA in malnourished animals, but could produce bacteria translocation. Yogurt could inhibit the growth of intestinal carcinoma through increased activity of IgA, T cells, and macrophages.

Animals↗

Caffeine clearance in subjects with constitutional unconjugated hyperbilirubinemia.

To investigate the behaviour of caffeine (CAF) in patients with Gilbert's Syndrome (GS), a combined oral loading test of caffeine and chenodeoxycholic acid was performed in 14 healthy subjects and 71 patients with GS. Indocyanine green (ICG) kinetics was tested in 50 subjects with GS and in all control subjects. Fasting serum bile acids (SBA) and clearance after CDCA loading were within normal range in normal and GS subjects. No significant difference in levels either of bilirubin or of SBA was observed in GS cases with normal (52 cases, 488 +/- 63 ml/min) or impaired (19 cases, 338 +/- 30 ml/min) caffeine clearance. Eleven GS cases showed altered ICG clearance. No correlation was found between bilirubin and bile acids, CAF or ICG. Fasting SBA were normal even in cases of CAF or ICG altered kinetics, thus excluding structural damage in unconjugated hyperbilirubinemia. CAF altered kinetics in 27% of GS cases may suggest multiple deficits in the hepatocellular metabolism, thus confirming the heterogeneity of this syndrome.

Adolescent↗

Biochemical and immunohistochemical multiparametric analysis of steroid receptors and growth factor receptors in human normal endometrium in spontaneous cycles and after the induction of ovulation.

This study was carried out with three aims: to assess the variations of receptors for beta-oestradiol and progesterone, and for epidermal growth factor (EGF), alpha-fibroblast growth factor (FGF) and beta-FGF, during a spontaneous cycle in normo-ovulatory patients, 2 days before, and 2 and 7 days after the day of ovulation; to compare the control group of patients with those given ovulation induction using a multiparametric approach; and to study the role of luteal supplementation with progesterone in two groups of patients treated by a luteinizing hormone-releasing hormone agonist plus human menopausal gonadotrophin. The results were assessed by biochemical analyses and by immunohistochemistry. In spontaneous cycles, a decrease in steroid receptors occurred during the luteal phase. There was an increase in EGF and EGF receptors which was induced by oestradiol secretion, and an increase during the luteal phase of alpha-FGF and beta-FGF, which are considered to be angiogenic factors. Comparisons between spontaneous and induced cycles showed a few variations in the endometrium but no differences were related to the type of ovulation induction.

Adult↗

Biochemical scores could reflect histological activity in chronic hepatitis C.

Eighty-one patients with HCV positive chronic active hepatitis (CAH) were studied to correlate, in multivariate regression analysis, liver tests with the histological activity index (HAI). The median HAI value (9.4) divided the patients into two groups; 44 under the 9.4 value (moderate CAH) and 37 above (severe CAH). Multiple regression improved the significance of nine biochemical parameters related to HAI in univariate analysis, and backward stepwise analysis identified the combination of alanine-aminotransferase (ALT), gammaglobulins (gamma GL), gammaglutamyl transpeptidase (gamma GT) and prolyl-hydroxylase (PH) as the best relationship with HAI (R = 0.520, p < 0.0001). A biochemical activity index (BAI) calculated as: 2.304 + ALT x 0.013 + gamma GL x 1.76 + gamma GT x 0.008 + PH x 0.012 showed the higher significant difference between moderate (7.7 +/- 1.3) and severe (12.2 +/- 2) CAH (p < 0.0001). These results suggest that this BAI could be a pointer for checking activity of chronic liver diseases.

Adult↗

Ceftazidime as monotherapy for fever and neutropenia: experience in a community hospital.

Fever and neutropenia is occurring in a wider variety of clinical settings, and the proper antibiotic therapy for its treatment is an area of debate. Our study is a retrospective analysis of the experience of the Oncology Division of the Medical Center of Baton Rouge, which used ceftazidime as monotherapy in the empiric treatment of fever and neutropenia. A total of 53 episodes in 38 patients were studied. Using ceftazidime as monotherapy in our study population was associated with an 8% mortality rate, indicating that monotherapy is a viable option for the treatment of fever and neutropenia.

Ceftazidime↗

Induction of antioxidant enzymes and DT-diaphorase in human blood mononuclear cells by light stress.

Human blood mononuclear cells exposed to visible light increase their antioxidant enzyme (superoxide dismutase, catalase, and glutathione peroxidase) and DT-diaphorase activities. The activities of CuZn-superoxide dismutase (3.70 +/- 0.25 U/mg protein), catalase (4.60 +/- 0.39 U/mg protein), and DT-diaphorase (1.40 +/- 0.11 mumol DCPIP/min.mg protein) increased 1.5-fold when mononuclear cells were exposed at 38 W/m2 for 4 h. Se-containing glutathione peroxidase activity (6.76 +/- 0.21 mU/mg protein) increased 1.3 times after 3 h of exposure to 38 W/m2. Conversely, Mn-superoxide dismutase (2.20 +/- 0.20 U/mg protein), succinate dehydrogenase (0.86 +/- 0.04 mumol DCPIP/min.mg protein), and cytochrome oxidase (0.54 +/- 0.04 min-1 (k')/mg protein) activities remained constant during this period of exposure. The treatment of cells with cycloheximide prevented the response triggered by light exposure. These results introduce new insight to the adaptive response of human cells to light stress suggesting that: (a) the response observed might be ascribed to synthesis of stress proteins rather than to activation of a preexisting pool, and (b) that DT-diaphorase and CuZn-superoxide dismutase may operate biologically in a concerted fashion resulting in antioxidant activity.

Adult↗

Cellular stress by light and rose bengal in human lymphocytes.

Human lymphocyte cultures were supplemented with 10(-8)-10(-4) M Rose Bengal and irradiated with fluorescent light (Philips 40-W daylight-fluorescent lamp, 380-550 nm) and chromosomal aberrations and catalase and superoxide dismutase activities in the cells were determined. Chromosomal lesions and both enzymatic activities increased additively or synergistically in human lymphocytes after Rose Bengal supplementation and fluorescent light irradiation. Chromosomal lesions (expressed as chromosomal aberrations/cells) were (a) 0.12 +/- 0.03, (b) 0.18 +/- 0.12, (c) 1.58 +/- 0.11 and (d) 3.20 +/- 0.17 in the following conditions: (a) control; (b) after 3 h light irradiation, (c) supplemented with 10(-5) M Rose Bengal and (d) with dye treatment and light irradiation. Superoxide dismutase activity was: (a) 16.5 +/- 1.5; (b) 19.5 +/- 1.2; (c) 29.2 +/- 1.5 and (d) 35.4 +/- 2.1 U/mg protein and catalase activity was: (a) 10.3 +/- 0.5, (b) 12.8 +/- 0.7, (c) 22.4 +/- 0.5 and (d) 27.6 +/- 1.1 U/mg protein in the same experimental conditions. These findings suggest that Rose Bengal supplementation plus fluorescent light irradiation of human lymphocytes lead to the synthesis of superoxide dismutase and catalase in a manner similar to the heat-shock response. A threshold of chromosomal damage (about 2 chromosomal aberrations/cell) is apparently required to activate oxidative stress genes.

Adult↗

Comparison of growth hormone responses to growth hormone-releasing factor and clonidine in women with normal or poor ovarian response to gonadotropin stimulation.

OBJECTIVE: To assess the reliability of growth hormone (GH) secretion tests using provocative agents in women of different ovarian status. DESIGN: Comparison of GH secretion in response to clonidine (Catapressan; Boehringer Ingelheim, Reims, France) and growth hormone-releasing factor (GH-RF). SETTING: University Hospital, Hôpital Tenon, Paris, France. PATIENTS: Women categorized as "normal" (n = 6) or "poor" responder (n = 7) to ovarian stimulation with gonadotropins, depending on the follicular development attained at previous IVF attempts. INTERVENTIONS: Clonidine (0.300 mg administered orally) once and GH-RF (1 micrograms/kg IV) repeated twice. The tests were performed in random order in each individual on following cycles. MAIN OUTCOME MEASURES: Basal and peak GH values, area under the curve (AUC). RESULTS: Poor responder patients show significantly higher basal levels of FSH, GH, and insulin-like growth factor 1; FSH and basal GH levels are positively correlated. Peak GH levels and AUC are not significantly different in both categories of patients, whether GH-releasing factor or clonidine are used as provocative agents. True positive rate is 56.4% at the cutoff value of 7 micrograms/L, with no significant difference between the patients of the normally or poorly responding groups. At the 10-micrograms/L cutoff level, the true positive rate is almost half in the poor responder group (19.0% versus 38.9%), but the difference is not significant. CONCLUSIONS: These results raise concern about using the GH secretory response to a single clonidine administration as a predictive test of the therapeutic benefit that could be obtained by co-stimulating the somatotropic axis during a treatment with gonadotropins in poor responder patients, especially when their FSH basal levels are elevated.

Adult↗