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M Teixeira

Publications and source records attributed to M Teixeira.

135 records · Page 8Linked to original sources
PubMed1982

Evidence for nickel and a three-iron center in the hydrogenase of Desulfovibrio desulfuricans.

Hydrogenase from Desulfovibrio desulfuricans (ATCC No. 27774) grown in unenriched and in enriched 61Ni and 57Fe media has been purified to apparent homogeneity. Two fractions of enzymes with hydrogenase activity were separated and were termed hydrogenase I and hydrogenase II. they were shown to have similar molecular weights (77,600 for hydrogenase I and 75,500 for hydrogenase II), to be composed of two polypeptide chains, and to contain Ni and non-heme iron. Because of its higher specific activity (152 versus 97) hydrogenase II was selected for EPR and Mössbauer studies. As isolated, hydrogenase II exhibits an "isotropic" EPR signal at g = 2.02 and a rhombic EPR signal at g = 2.3, 2.2, and 2.0. Isotopic substitution of 61Ni proves that the rhombic signal is due to Ni. Combining the Mössbauer and EPR data, the isotropic g = 2.02 EPR signal was shown to originate from a 3Fe cluster which may have oxygenous or nitrogenous ligands. In addition, the Mössbauer data also revealed two [4Fe-4S]2+ clusters iun each molecule of hydrogenase II. The EPR and Mössbauer data of hydrogenase I were found to be identical to those of hydrogenase II, indicating that both enzymes have common metallic centers.

Desulfovibrio↗
PubMed1982

Anticonvulsant activation of pain-suppressive systems.

The effect of diphenylhydantoin, sodium valproate and carbamezepine on the enzymatic activity of the anterior mesencephalic periaqueductal grey matter was examined by a histochemical technique using density phase measurement. Diphenylhydantoin caused the greatest reduction in glutamate dehydrogenase and GABA. Only sodium valproate increased glutamate dehydrogenase and GABA and only diphenylhydantoin an increase in semi-aldehyde dehydrogenase activity. Central pain suppressive systems can be activated by certain anticonvulsants.

Aldehyde Oxidoreductases↗
PubMed1980

Microcirculatory studies in rat mammary carcinoma. I. Transparent chamber method, development of microvasculature, and pressures in tumor vessels.

Fragments of a mammary adenocarcinoma were implanted into transparent tissue chambers in the dorsal skin flaps of female inbred F344 rats. A chamber modification permitted repeated access to the tissue without infection, vessel disruption, or impairment of tumor growth. Tumors completely filled the chambers after 26-30 days. Development of tumor microvasculature was characterized by increase in number, length, and diameter of vessels. These changes were much more pronounced in capillaries and venules than in arterioles. Direct blood pressure measurements were performed in microvessels throughout the tumor during the first 3 weeks of growth as well as in microvessels of tumor-free control preparations containing subcutaneous tissue. Average pressures in arterioles of 40- to 11-micron diameter were between 23.0 and 17.3 cm H2O in tumors versus 25.5 and 16.2 cm H2O in controls. Average pressures in venous capillaries, venules, and veins up to 150-micron diameter were between 9.1 and 8.1 cm H2O in tumors and between 13.4 and 11.0 cm H2O in controls.

Adenocarcinoma↗
PubMedDate not supplied

Simultaneous pancreas-kidney transplantation: five-year results from a single center.

We report the 5-year results of our simultaneous pancreas-kidney transplantation (SPKT) program, started on May 2, 2000. Forty-two SPKT were performed on 42 type I diabetic patients with chronic renal failure. The procedure was performed with enteric diversion and vascular anastomosis to the iliac vessels. Immunosuppressive protocol included antithymocyte globulin, tacrolimus, mycophenolate mofetil, and steroids. The 24 women and 18 men had a mean age of 33.5 +/- 6.3 years and mean 22.8 +/- 14.2 years time of diabetes evolution. Forty patients had been on dialysis for 34.3 +/- 24.1 months, and two were preemptive transplantations. Acute rejection episodes were treated in eight patients (19.1%): in three cases they affected both organs; in two only the kidney was affected; and the other three were pancreas graft rejections. The incidence of postoperative complications requiring re-operation was 42.9%, mostly pancreas graft related. Two patients died, one due to cardiovascular disease; the other was transplant related. Three kidney grafts were lost, and the causes were immunologic, thrombosis, and patient death. Pancreas graft loss occurred in seven patients: thrombosis (n = 3); infection (n = 3); immunologic (n = 1). The patients with surviving grafts were doing well, with normal kidney and pancreas function: serum creatinine = 0.89 +/- 0.15 mg/dL; fasting blood glucose = 79 +/- 16 mg/dL; HbA1c = 4.7 +/- 1.1%. The 1-year patient, kidney, and pancreas survival rates were 97.3%, 94.6%, and 83.8% and 5-year values, 91.7%, 89.2%, and 78.7%, respectively. In conclusion, these results are similar to the most recent UNOS/IPTR reports, leading us to consider our experience with SPKT very positive.

Adult↗
PubMedDate not supplied

[Evolution of the detection of interventricular septal defect].

From 24.10.1969 to 31.12.1986, seventeen years, 1274 infants and children with proven isolated ventricular septal defect were observed and followed in Pediatric Cardiology of Santa Marta Hospital. There were 659 males and 615 females, ranging from 3 days to 12 years, born in portuguese territory and without syndromes. As early detection and referring is crucial to prevent pulmonary vascular disease with fixed pulmonary arterial resistance, the annual variation of the referring age was studied. The results improved since 1972 with a steady faster improvement during the last 7 years of the study.

Child↗
PubMedDate not supplied

Uses and limitations of the Crohn's disease activity index.

The Crohn's Disease Activity Index (CDAI) proposed by a US Working Party was used in 39 Crohn's patients attending a combined medical and surgical gastrointestinal unit as out and inpatients. It proved easy to use and a range of values from 0 to 294 was obtained. Analysis of the contribution of its 8 components suggested a very considerable emphasis on well-being and haematocrit. No correlation with location of disease was found but there was a correlation with hospital admission and subjective assessment. Low values were found in several patients who, although known to have extensive disease were well on medical therapy. Therefore the Index measured the activity not the extent or presence of Crohn's disease. It is a very useful measure for clinical trials but in no way could replace full clinical assessment.

Crohn Disease↗