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Biomedical subjects

A Ortega

Publications and source records attributed to A Ortega.

At least 163 records · Page 9Linked to original sources
PubMed1993

Excitatory amino acid-induced phosphoinositide hydrolysis in Müller glia.

The presence of excitatory amino acid (EAA) receptors coupled to phosphoinositide metabolism in primary cultures of Müller (glial) cells from the chick retina was established. The order of potency of analogues for stimulating [3H]inositol phosphate (IP) accumulation was quisqualate (QA) > L-glutamate (L-Glu) = kainate (KA) > N-methyl-D-aspartate (NMDA) > L-aspartate (L-Asp) with EC50 in the range of 1-100 microM. 1-Aminocyclopentane-1,3-dicarboxylate (trans-ACPD), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), 2-amino-3-phosphonopropionate (AP3), and 2-amino-4-phosphonobutyrate (AP4) showed no effect either on basal concentration or on stimulated accumulation of [3H]IPs. The effect of EAA was potently inhibited by the ionotropic NMDA receptor antagonists 2-amino-5-phosphonopentanoate (AP5), 3-[(RS)-2-carboxy-piperazin-4-yl)]-propyl-1-phosphonate (CPP), and (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-10- imine (MK-801); L-Glu antagonists at non-NMDA receptors, the quinoxalines NBQX and DNQX, inhibited weakly the response to L-Glu, KA, and NMDA, and more potently that to QA. The translocation of protein kinase C was also stimulated by EAA with the same pharmacological profile, and was partially inhibited by kynurenate (KYN). L-Glu and KA induced 45Ca2+ influx, which was decreased by KYN and CNQX. EAA-induced [3H]IPs accumulation was decreased by verapamil but not by nifedipine, and slightly diminished by dantrolene. Results demonstrate that EAA-induced phosphoinositide hydrolysis in Müller cells shows pharmacological differences with that in astrocytes and neuronal cells and could be triggered by a different mechanism.

2-Amino-5-phosphonovalerate↗
PubMed1993

Sedative effect of galphimine B, a nor-seco-triterpenoid from Galphimia glauca.

Galphimia glauca Cav. (Malpighiaceae) is used in Mexican traditional medicine as a sedative in the treatment of mental disorders. Sedative properties of a methanolic extract of the aerial parts of this plant have been established in animal trials and an active compound, named galphimine B, has already been isolated. This compound was submitted to neuropharmacological testing, where it was shown that galphimine B had no significant effect as an anticonvulsant, while it exhibited a strong depressant activity on the nervous system.

Animals↗
PubMed1993

Effects of repeated neuropsychological assessments.

The effects of repeated administrations of neuropsychological instruments were evaluated in a group of chronic cigarette smokers who served as control subjects in a larger research project. Subjects performance on 13 neuropsychological variables across four assessments was evaluated using trend analyses. Statistically significant results were obtained on the Logical and Figurai Memory Subtests of the Wechsler Memory Scale (Form I-Russell's Revision) Part B of the Trail Making Test and the Grooved Pegboard Test (preferred hand). Of the remaining seven variables the Speech Sounds Perception Test, the Seashore Rhythm Test and Simple Auditory Reaction Time were highly consistent across all four assessments. The implications of these findings in clinical practice and research settings are addressed.

Journal Article↗
PubMed1993

Peri-implantitis.

Explore the source record for details and available documents.

Dental Implants↗
PubMed1993

The physiology of laparoscopic surgery: pulmonary function after laparoscopic cholecystectomy.

Changes in pulmonary function were studied via standard spirometry in 30 patients after laparoscopic cholecystectomy (LC) and compared with those in nine patients after traditional open cholecystectomy (OC). Studies performed presurgery and the morning after surgery included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and forced expiratory flow (FEF25%-75%). Age (43.9 +/- 2.6 years for LC and 42.3 +/- 3.2 for OC), sex, reasons for cholecystectomy, and smoking history were similar in both groups. The mean FVC decreased 23% after LC (3.57 +/- 0.18 L presurgery, range 0.56-5.62, versus 2.68 +/- 0.17 postsurgery, range 0.65-5.14) and 35.2% after OC (mean 3.52 +/- 0.29 presurgery, range 2.38-4.99, versus 2.24 +/- 0.24, range 1.23-3.49 postsurgery). FEV1 showed similar changes, with LC decreasing pulmonary function by 24.3% (2.76 +/- 0.14 L presurgery versus 2.01 +/- 0.12 postsurgery) compared with a 36.2% reduction in FEV1 after OC (2.86 +/- 0.29 L presurgery versus 1.81 +/- 0.21 L postsurgery). Forced expiratory flow decreased by 24.3% after LC and 40% after OC. Laparoscopic cholecystectomy provides less decrement in pulmonary function than traditional open cholecystectomy.

Adult↗
PubMed1992

Tuberculous meningitis in patients infected with the human immunodeficiency virus.

BACKGROUND AND METHODS: Tuberculosis is a frequent complication of human immunodeficiency virus (HIV) infection. We describe the clinical manifestations and outcomes of tuberculous meningitis in patients with HIV infection, and compare them with those in non-HIV-infected patients. We reviewed the records from 1985 through 1990 at two large referral hospitals in Madrid for patients who had Mycobacterium tuberculosis isolated from cerebrospinal fluid. RESULTS: Of 2205 patients with tuberculosis, 455 (21 percent) also had HIV infection, of whom 45 had M. tuberculosis isolated from the cerebrospinal fluid. Of the 37 HIV-infected patients with tuberculous meningitis for whom records were available, 24 (65 percent) had clinical or radiologic evidence of extrameningeal tuberculosis at the time of admission. In 18 of 26 patients (69 percent), a CT scan of the head was abnormal. In most patients, analysis of cerebrospinal fluid showed pleocytosis (median white-cell count, 0.234 x 10(9) per liter) and hypoglycorrhachia (median glucose level, 1.3 mmol per liter), but in 43 percent (15 of 35), the level of protein in cerebrospinal fluid was normal. In four patients with HIV infection, tuberculosis was only discovered after their deaths. Of the 33 patients who received antituberculous treatment, 7 died (in-hospital mortality, 21 percent). Illness lasting more than 14 days before admission and a CD4+ cell count of less than 0.2 x 10(9) per liter (200 per cubic millimeter) were associated with a poor prognosis. Comparison with tuberculous meningitis in patients without HIV infection showed that the presentation, clinical manifestations, cerebrospinal fluid findings, and mortality were generally similar in the two groups. However, of the 1750 patients without HIV infection, only 2 percent (38 patients) had tuberculous meningitis, as compared with 10 percent of the HIV-infected patients (P less than 0.001). CONCLUSIONS: HIV-infected patients with tuberculosis are at increased risk for meningitis, but infection with HIV does not appear to change the clinical manifestations or the outcome of tuberculous meningitis.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Influence of different upper age limits on the "Years of Potential Life Lost" index.

The use of 65, 70 or 75 years as upper age limits for the "Years of Potential Life Lost" index (YPLL) could influence the relative importance assigned to different causes of premature death. Data from a representative year (1987) in Catalonia (Spain), show that health priorities and comparability among studies are not affected by the use of these upper age limits.

Age Factors↗
PubMed1992

Tuberculous meningitis with acellular cerebrospinal fluid in AIDS patients.

OBJECTIVE: To describe the clinical manifestations of tuberculous meningitis in HIV-positive patients with acellular cerebrospinal fluid (CSF). DESIGN: Retrospective analysis of case reports. METHODS: Four HIV-positive patients with acellular CSF and tuberculous meningitis are reported. RESULTS: Clinical presentation did not indicate meningeal infection in three of the four cases, and CSF tests were unusual in all cases. Two patients were diagnosed only after death. CONCLUSIONS: Acellular CSF may obstruct the diagnosis of tuberculous meningitis in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Serological diagnosis of pulmonary tuberculosis using ELISA and the A60 antigen].

BACKGROUND: Study of the utility of a serologic technic in the clinic diagnostic of the pulmonary tuberculosis. METHODS: An indirect enzyme-linked immunosorbent assay (ELISA) for detecting serum antibodies (IgG) against the antigen A60 has been applied to 170 tuberculosis patients (151 adults and 19 children) and 35 healthy children not protected with BCG. RESULTS: The ELISA results obtained with tuberculosis patients were: 84.8% positive IgG in adults and 21.1% in children. The percentage of serologically positive cases in healthy children against the antigen A60 was 11.5%. All the results were statistically significant (p less than 0.01). CONCLUSIONS: This test can be successfully applied as a support technique in the diagnosis of pulmonary tuberculosis in adults, it will be necessary to know the endemic situation in each community analysed.

Adult↗
PubMed1992

Meningeal fibrosarcoma: a case report and review of the literature.

Meningeal Fibrosarcoma (MF) accounts only for 0.5% of the brain tumors. Since the clinical manifestations and radiologic findings are non-specific, the diagnosis can only be achieved by pathological examination of surgically removed specimens. MF are tumors that behave locally very aggressively and respond poorly to treatment, with reported median survivals ranging from 6 to 15 months. We report a new case of MF describing the peculiar onset as a slow growing mass in scalp with bone destruction and without neurological clinical findings.

Adult↗
PubMed1992

Effects of administration route on pharmacokinetics of viloxazine in the rabbit.

The absorption of viloxazine chlorhydrate was investigated in ten rabbits. Each animal received the drug (15 mg/kg) by three routes: intravenous, gastric and duodenal. Viloxazine plasma concentrations were low when administered by gastric and duodenal routes compared to those after intravenous injection. Concentrations to peak were 1-2 times higher after duodenal than gastric administration. Times to peak were 23.0 +/- 4.7 min after gastric administration and 9.5 +/- 5.4 min after duodenal administration. A better absorption of viloxazine after administration occurred in the duodenum than in the stomach; these results agree with viloxazine pKa = 8.13. The other pharmacokinetic parameters such as half-life, clearance and volume of distribution where the same irregardless of the administration route.

Administration, Oral↗
PubMed1991

[The analysis of mortality in urban areas].

BACKGROUND: To investigate health status inequalities in small urban areas, using mortality differences between districts of Reus (pop. 85000), Spain. METHODS: For the period 1986-1988, data from the Civil Register and from death certificates issued indicated 1521 valid cases. Infant mortality, adjusted mortality indices (AMI) and years of potential life lost (YPLL) were calculated for the 17 groups of cause-of-death based on the International Classification of Diseases and Preventable Causes of Death. Both indicators (AMI and YPLL) were studied for each district and for the city as a whole. The exact confidence limits for the Standard Mortality Ratio were calculated. RESULTS: Although AMI and YPLL gave results that were quantitatively very different, districts IV and VIII consistently had the worst indices while districts II and VI had the best. CONCLUSION: Archive data over a period of several years together with exact calculation methods, can demonstrate inequalities in health or in socioeconomic conditions even in small areas. These methods may also be useful in delineating different urban living areas.

Age Factors↗
PubMed1991

Maternal and developmental toxicity of low doses of cytosine arabinoside in mice.

1-beta-D-Arabinofuranosylcytosine (Ara-C), an effective drug for the treatment of leukemia and breast cancer, was evaluated for developmental toxicity in pregnant Swiss mice. Ara-C was administered by intraperitoneal injection on gestational days 6-15 at doses of 0, 0.5, 2, and 8 mg/kg/day. Maternal observations included clinical signs, body weight change, food consumption, and gross evaluation of organs and uterine contents at necropsy (day 18). Live fetuses were examined for external, visceral, and skeletal alterations. Maternal toxicity was observed at 2 and 8 mg/kg/day, as evidenced by a significant decrease in body weight gain and food consumption during the treatment period. Significantly increased early and late resorptions and reduced number of live fetuses per liter as well as decreased fetal body weight were observed at 8 mg/kg/day. At 2 mg/kg/day, the incidence of cleft palate, renoureteral agenesis or hypoplasia, and poly- or oligodactyly was significantly increased, whereas fetal weight was reduced at 0.5 mg/kg/day. Thus, the developmental no-observed-adverse-effect-level (NOAEL) of Ara-C in the pregnant mouse is lower than 0.5 mg/kg/day, while the NOAEL for maternal toxicity is 0.5 mg/kg/day. We believe that exposure to this agent ought to be avoided during organogenesis.

Abnormalities, Drug-Induced↗