Biomedical subjects

L Cortez

Publications and source records attributed to L Cortez.

6 recordsLinked to original sources

PubMed1993

Survey of butyltin contamination in Portuguese coastal environments.

Butyltin compounds (MBT, DBT and TBT) in intertidal sediments collected in four different Portuguese coastal environments have been measured in order to evaluate the extent of contamination. The sites chosen were the Rias of Aveiro and Faro, and the Sado and Tejo estuaries. These zones were traditional areas for shellfish production in the recent past, but the effects of industrial development have caused a deterioration of the environment. Specific contaminations were derived from the harbour (commercial and/or fisheries) and shipyard activities, resulting in a release of TBT and causing the oyster populations of the above mentioned estuaries to almost disappear. Results presented in this study give a survey of TBT contamination levels found in the four areas. The paper discusses the importance of the pollution in comparison with other European coastal areas.

Journal Article↗

PubMed1992

[Myxedema coma].

Five patients, 4 female and 1 male, aged 45 to 73, were observed in myxedema coma between 1984 and 1992. In three patients hypothyroidism was not known. Depressed consciousness, hypothermia, bradycardia and no goiter were common to all and a precipitating factor could be identified in 3 of them. Therapy included L-thyroxine and/or triiodothyronine by nasogastric tube, hydrocortisone and supportive measures. Outcome was good in the 2 patients with known precipitating event, less impaired consciousness and normalization of body temperature by the third day of treatment.

Aged↗

PubMed1989

Impact of industrial and mine drainage wastes on the heavy metal distribution in the drainage basin and estuary of the Sado River (Portugal).

This paper presents results from a survey of the heavy metal distribution in sediments in the drainage basin and estuary of the Sado River (Portugal). In the drainage basin, heavy metals originate mostly from pyrite outcrop erosion and mining activities (Cd, Zn, Cu and locally Hg, Pg), and also from crust erosion (Sn, Ni, Ti, Zr). These sources are not correlated with the particulate organic carbon (POC) and so the metals are thought to be in inorganic forms in this area. Anthropogenic heavy metal sources (urban and industrial) are found in the lower estuary (Sn, Cd, Hg, Zn, Pb and Cu) along with high POC concentrations. In this zone, these metals are thought to be strongly adsorbed onto organic particles. Furthermore, organo-metallic species are likely to be present, as demonstrated in the case of Sn, since methyl- and butyl-tin species were detected in sediments from this area. This suggests the need for the detection of organo-metallic species to understand the heavy metal geochemical cycles. No long-term changes in metal concentrations are found in sediment cores, except in the middle estuary (Zn, Cu) due to the development of mining activities on an industrial scale in the 1860s.

Journal Article↗

PubMed1988

Degradation of bromacil by a Pseudomonas sp.

A gram-negative rod, identified as a Pseudomonas sp., was isolated from soil by using bromacil as the sole source of carbon and energy. During growth on bromacil or 5-bromouracil, almost stoichiometric amounts of bromide were released. The bacterium was shown to harbor two plasmids approximately 60 and 100 kilobases in size. They appeared to be associated with the ability to utilize bromacil as a sole source of carbon and also with resistance to ampicillin. This microorganism also showed the potential to decontaminate soil samples fortified with bromacil under laboratory conditions.

Alcohol Oxidoreductases↗

PubMed1987

Spontaneous suppressor cell activity in patients with the acquired immune deficiency syndrome and associated conditions.

Patients with the acquired immune deficiency syndrome (AIDS) have depressed cell-mediated immunity partially explained by a depletion of helper-inducer T-lymphocytes. We questioned if the remaining elements of the mononuclear cell (MNC) population also played a part in the immunologic abnormalities noted. We therefore evaluated the ability of MNC populations from homosexuals with AIDS and AIDS-associated conditions to suppress the mitogenic responses of control MNCs in an assay of "spontaneous suppressor" cell activity (SSCA). Asymptomatic homosexuals and homosexuals with chronic lymphadenopathy, Kaposi's sarcoma, or opportunistic infections (OIs) had levels of SSCA equal to or greater than that of control subjects. Levels were significantly higher in patients with lymphadenopathy (p less than or equal to 0.1) and in patients with OI (p less than or equal to 0.05). Although percentages of Ia+ cells were increased in all homosexual groups and highest in patients with OIs (p less than or equal to 0.05), percentages of either monocytes or suppressor/cytotoxic T-lymphocytes, potential mediators of SSCA function, did not correlate with levels of SSCA observed. Therefore, patients with AIDS and AIDS-associated conditions have MNC populations that appear to interact in producing normal or augmented down regulation of residual T-lymphocyte function, even in the face of helper/inducer T-lymphocyte depletion.

AIDS-Related Complex↗

PubMed1978

A new case of gamma-heavy chain disease.

The first case of gamma-heavy chain disease described in Spain is here reported. The patient, a 36-year-old woman, presented fever, enlarged regional lymph nodes, and hepatosplenomegaly, without bone marrow abnormalities but with lymphopenia. Serum electrophoresis did not disclose any M-component. The abnormal gamma-chain protein had a alpha2-globulin mobility and was immunochemically related to the Fc fragment. It belonged to the IgG 4 subclass, its molecular weight was about 60,000. Proteinuria was minimal but the electrophoresis of concentrated urine showed a homogeneous peak of alpha2-globulin mobility constituted by the gamma-chain fragment. Biopsy of an axillary lymph node disclosed features of immunoblastic sarcoma. The course was malignant, resulting in death in 8 months.

Adult↗