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Biomedical subjects

R Martinez

Publications and source records attributed to R Martinez.

At least 343 records · Page 19Linked to original sources

Advantages of the rapid HIV-1 test in occupational accidents with potentially contaminated material among health workers.

In occupational accidents involving health professionals handling potentially contaminated material, the decision to start or to continue prophylactic medication against infection by Human Immunodeficiency Virus (HIV) has been based on the ELISA test applied to a blood sample from the source patient. In order to rationalize the prophylactic use of antiretroviral agents, a rapid serologic diagnostic test of HIV infection was tested by the enzymatic immunoabsorption method (SUDS HIV 1+2, MUREX) and compared to conventional ELISA (Abbott HIV-1/ HIV-2 3rd Generation plus EIA). A total of 592 cases of occupational accidents were recorded at the University Hospital of Ribeirão Preto from July 1998 to April 1999. Of these, 109 were simultaneously evaluated by the rapid test and by ELISA HIV. The rapid test was positive in three cases and was confirmed by ELISA and in one the result was inconclusive and later found to be negative by ELISA. In the 106 accidents in which the rapid test was negative no prophylactic medication was instituted, with an estimated reduction in costs of US$ 2,889.35. In addition to this advantage, the good correlation of the rapid test with ELISA, the shorter duration of stress and the absence of exposure of the health worker to the adverse effects of antiretroviral agents suggest the adoption of this test in Programs of Attention to Accidents with Potentially Contaminated Material.

AIDS Serodiagnosis↗

[Cryptococcus meningitis: clinical course, development and histopathologic aspects depending on the predisposing factors].

Seventeen consecutive cases of cryptococcal meningitis diagnosed at Hospital das Clínicas of Ribeirão Preto Medical School (São Paulo State Brazil) between 1969 and 1985 were reviewed. For analysis the patients were separated in 3 groups: I. three patients without immunodeficiency; II. six patients with associated disease: cancer (3), diabetes (2) and alcoholism (1); III. Eight renal transplant recipients that developed cryptococcosis after 18 to 67 months of immunosupression with steroids and azathioprine. The median interval between onset of symptoms and diagnosis of infection was greater in Group II (53 days) than in Groups I (25 days) or III (28 days). Neck stiffness, cranial nerve involvement and papilledema were more frequent in Group I than in Group II or III, but fever and focal neurological signs were observed only in patients of two last groups. Cerebrospinal fluid examination showed a mild lymphocytic pleocytosis in most patients, but transplant cases had polymorphonuclear cells more frequently. Late mortality was higher in patients with underlying disease and the prognosis was better for transplant patients that received effective antifungal therapy. Besides cryptococci, autopsy findings in 8 cases revealed granuloma formation in tissues, except in patients of Group II (2 cases). The differences between the groups suggest that clinical characteristics, evolution and postmortem findings of the cryptococcal meningitis are changed according to type of immunodeficiency presented by the patient.

Adolescent↗

The epidemiological impact of antimeningococcal B vaccination in Cuba.

The incidence of invasive meningococcal disease (IMD) before (1984-1988) and after (1989-1994), a nationwide intervention with VA-MENGOC-BC vaccination started in 1989, was compared. The prevaccination period incidence density (ID> 8.8/10(5) year-person) was higher than the postvaccination ID (ID< 6.5/10(5) year-person). The percentage proportional differences from the start to the end of each period of ID in the vaccinal period was higher (87%) than the prevaccinal (37%) with significant differences among vaccinated groups (< 25 years old). A break-point (Chow test) was confirmed by the decrease in the ID between 1989 and 1990 in children under 1 year old, 5-9, 10-14, 15-19 and 50-54 years. Comparison of ID using maps showed a decrease in IMD in all municipalities during the postvaccination period. These findings support the epidemiological impact of VA-MENGOC-BC vaccination in the reduction of IMD morbidity.

Adolescent↗

Subcellular distribution of phospholipase A2 and ATPases during capacitation and acrosome reaction in guinea pig spermatozoa.

The presence, distribution, and levels of phospholipase A2 and ATPases activities in those structures of the guinea pig spermatozoa that participate in the acrosome reaction were studied, both before and after capacitation, as well as during the acrosome reaction induced in vitro. Spermatozoa were collected from the cauda epididymis and incubated in the absence and presence of 1.15 mmol/L calcium, with and without the addition of 1 mumol/L A23187. Membrane fractions were recovered by vortexing and discontinuous sucrose density gradient centrifugation. Most of the Na+, K(+)-ATPase was recovered in the acrosome-free spermatozoa, but a clear, distinct presence of this enzyme was observed in the plasma membrane (25 against 101 nmoles Pi released per milligram of protein, respectively). The activity of this enzyme in the periacrosomal plasma and in the outer acrosomal membrane increased during calcium incubation. Ca2(+)-dependent ATPase was found in both membrane fractions, being higher in the periacrosomal plasma membrane. The addition of calcium induced a significant inhibition of this acrosomal ATPase, whereas the activity in the acrosome-free spermatozoa increased. The activity of phospholipase A2, under all experimental conditions, was found to be restricted to the soluble fraction.

Acrosome↗

Evaluation of the antimicrobial susceptibilities of coagulase-negative staphylococci by E-test.

Coagulase-negative staphylococci (CoNS) have recently emerged as important nosocomial pathogens. In this study, the susceptibility of 53 isolates of CoNS (42 S. epidermidis, 6 S. haemolyticus, 3 S. caprae, 1 S. lugdunensis and 1 S. chromogenes) obtained over a 1 year period at a Brazilian Hospital were tested for vancomycin, teicoplanin, cephalothin, penicillin, oxacillin, and chloramphenicol. The minimal inhibitory concentration (MICs) were determined by the E-test using saturated swabs or the flooding method. No isolates showed resistance to vancomycin, 3 (5.7%) were resistant to teicoplanin, 5 (9.4%) to cephalotin, most of them, (47, 88.6%) were resistant to penicillin, 19 (35.8%) to oxacillin and 27 (50.9%) to chloramphenicol. The study shows that the increased resistance of CoNS can cause serious infections of difficult treatment. The E-test proved to be a convenient and reliable method for MIC determination of CoNS isolates and the qualitative and quantitative results obtained by flooding were much more reproducible than the results obtained using swabs.

Bacterial Proteins↗

[Hypogammaglobulinemia as risk factor for Cryptococcus neoformans infection: report of 2 cases].

Two HIV-seronegative patients with cryptococcal disease refractory to conventional antifungal therapy were submitted to an evaluation of the immune system. Hypogammaglobulinemia was found in both and associated with abnormal function of cell-mediated immunity. Hypogammaglobulinemia is considered as a possible predisposing factor for cryptococcal infection. The importance of the antibodies on the control of Cryptococcus neoformans infection is discussed.

Adult↗

[Nosocomial urinary tract infections by Candida species].

BACKGROUND: Isolation of a yeast in urine does not necessarily indicate infection, but Candida urinary tract infection is an increasing nosocomial problem. In this study the clinical significance of candiduria was investigated in a Brazilian university hospital. METHODS: Between January and December 1998 species of Candida were isolated in the urine of 166 patients admitted to a tertiary-care general hospital at Ribeirão Preto, SP, Brazil. The data of 100 of these patients were retrospectivelly reviewed concerning microbiological, epidemiological, and clinical aspects of candiduria. RESULTS: C. tropicalis was found in 53% of the patients and C. albicans in 36%. Urine cultures yielded more than 20.000 yeast colonies/ml in 76% of cases. Neurological, cardiac and other chronic diseases, cancer, and trauma were frequent underlying illnesses. Diabetes mellitus was present in 25% of patients. The major predisposing factors associated with candiduria were previous antibiotic therapy (93%) indwelling urinary catheter (83%), surgery in the last 60 days (48%), renal failure (32%), concomitant bacterial infections (28%), use of corticosteroids (20%), and use of other immunosuppressive drugs (10%). Therapy for candiduria, fluconazole or amphotericin B with one exception, was given only to 43/100 patients. The overall mortality in the 60 days after the candiduria episode was 40%. CONCLUSIONS: The non-albicans species of Candida were the major agents of candiduria and are emergent pathogens of the urinary tract in critically ill patients. The underlying illnesses, risk factors and high mortality commonly associated with Candida urinary tract infection were also observed in a Brazilian university hospital.

Adolescent↗

[Gastric paracoccidioidomycosis. A case report and considerations on the pathogenesis of this disease].

The authors report an unusual case of fungal gastric lesion in a patient with the chronic form of paracoccidioidomycosis. For a period of 8 months the major symptoms of the patient were abdominal pain and body weight loss. The endoscopic evaluation of the upper gastrointestinal tract showed a partial gastrectomy made previously, a great and irregular ulcer in the stomach and a granulated aspect of the duodenal mucosa. A granulomatous process and Paracoccidioides brasiliensis were observed in the histopathological examination of the gastric and duodenal biopsy tissue. New endoscopic evaluation 4 months after treatment with sulfadiazine revealed healing of the gastric ulcer. It was suggested that abdominal lymph nodes involvement, duodenal infection and anatomical and atrophic alterations of the stomach were predisposing factors for the gastric paracoccidioidomycosis.

Chronic Disease↗

[Diabetic cardiomyopathy: possible pathogenetic role of coronary microcirculation].

The hypothesis that diabetes mellitus provokes a specific cardiomyopathy is supported by numerous clinical, epidemiological and anatomopathological studies. However, the frequent association of diabetes mellitus with other conditions, such as hypertension and coronary atherosclerosis, both capable of causing the dysfunction of the cardiac muscle, makes it difficult to interpret many of the data reported in the literature and contributes to the continuing debate regarding the effective existence of diabetic cardiomyopathy and its possible pathogenetic mechanisms. In clinical terms, diabetic cardiomyopathy is manifested both as an altered diastolic and/or systolic phase, assessed using various non-invasive techniques, or as congested cardiac decompensation. The pathogenesis of diabetic cardiomyopathy is still not altogether clear. The alteration of the smallest coronary vessels might be responsible for the increased interstitial fibrosis found in the heart of diabetic patients. In this paper numerous data from the literature on this argument are reported and the authors advance the hypothesis that endothelial dysfunction may play a pathogenetic role in the development of cardiopathy.

Cardiomyopathies↗

Glioblastoma multiforme of the pineal region.

A case of glioblastoma multiforme restricted to the pineal region is presented. Although glioblastomas of the pineal region are exceedingly rare, they have to be considered in the differential diagnosis of tumors at this localization.

Brain Neoplasms↗

[Elimination of viscoelastic substances from the vitreous cavity. Comparative study of sodium hyaluronate and hydroxypropylmethylcellulose].

We study the elimination of two viscoelastic substances from the vitreous cavity: the Hydroxypropyl Methylcellulose and the Sodium Hyaluronate that are potentially vitreous substitutes. We performed gas-vitrectomy in 116 eyes of 58 rabbits. Three days after surgery we performed gas-viscoelastic substance exchange. We analyzed the concentration of Hydroxypropyl Methylcellulose and Sodium Hyaluronate with diphenylamine reaction at different periods: zero, 1 week, 2 weeks, 1 month till 6 months. In both cases the elimination is fast so that 1 week after the intravitreal injection remains only 60.1% of the Hydroxypropyl Methylcellulose and 100% of Sodium Hyaluronate, and two weeks after 38.5% of Hydroxypropyl Methylcellulose and 62.5% of Sodium Hyaluronate. We conclude that both substances have a short half life-time specially in the case of the Hydroxypropyl Methylcellulose.

Animals↗