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V Costa

Publications and source records attributed to V Costa.

70 records · Page 4Linked to original sources

Oxidative stress and signal transduction in Saccharomyces cerevisiae: insights into ageing, apoptosis and diseases.

In yeast, as in higher eukaryotes, reactive oxygen species are produced as normal by-products of cellular metabolism. Under physiological conditions, the cell defence mechanisms are able to avoid molecular damages. This balance is disturbed when yeast cells are exposed to diverse environmental stress conditions, such as the presence of oxidants, heat shock, ethanol and metal ions. The increased production of reactive oxygen species is sensed by the cell, leading to the induction of defence mechanisms - the oxidative stress response. The present review discusses the mechanisms by which reactive oxygen species are sensed and the signalling pathways that are coupled with changes in genomic expression programs. Yeast has been used as an eukaryotic cell system to characterise the molecular mechanisms underlying the oxidative stress response. Furthermore, yeast has been utilised to elucidate the role of oxidative stress in ageing, apoptosis, and diseases, such as familial amyotrophic lateral sclerosis and Friedreich's ataxia.

Aging↗

[Prevalence of cutaneous lesions in Freixo de Espada à Cinta].

Incidence or prevalence studies on cutaneous lesions in general populations are not available. The community observed by the authors (Freixo de Espada à Cinta, North-Eastern Portugal) is relatively closed. A pre-tested questionnaire for socio-demographic and clinical information was used and a physical observation was conducted in January and February 1994 by the Dermatology Team of Santo António General Hospital, Oporto. The analysis was supported by independent tests (Pearson and Fisher chi 2, Student-t, Mann-Whitney and Kruskall-Wallis). The Spearman correlation coefficient was also used. The results indicated that 51.9% of 1000 subjects analysed were in phototype III. Concerning specific pathologies, the following percentages were observed: melanocytic nevi 81.2; hemangiomas 26.5; androgenetic alopecia 20.5; deshydrotic eczema 12.7; seborrheic keratosis 11; solar keratosis 9.6; acne vulgaris 9.5; seborrheic dermatitis 6.9; superficial mycosis 6.4; other dermatitis 5.5; vascular spiders 4.4; vulgar psoriasis 1.9; vulgar warts 1.5; pediculosis and scabiosis 1.2.; herpes simplex 0.9; impetigo 0.7; tumours (neoplasias) 0.7; dysplastic nevi 0.6; urticaria 0.3. More than nine nevi were counted in 50% of the subjects observed. A difference was observed (p < 0.05) concerning the presence of nevi, mycosis, hemangiomas, non-specific dermatitis, vascular spider and solar keratosis according to sex. The females had more nevi in number than males (Mann-Whitney, p = 0.03). According to age there was a difference concerning the presence of nevi, superficial mycosis, deshydrotic eczema, seborrheic dermatitis, acne, psoriasis, tumours, hemangiomas, non-specific dermatitis, vascular spider, solar keratosis (with linear augmentation by age) and seborrheic keratosis. Nevi increased with ageing (Rs = 0.10 p < 0.001) and a greater number were observed in age groups 0-9 and 60 or more years. Acne was observed in 9.4% of the females and 9.7% of the males, 46.2% in the 15-29 year-old age group. This study indicated that the population had a mean of nine nevi. Psoriasis was similar to that mentioned in other studies: about 1% in the United States of America. Atopic dermatitis (5.5%) is below the values for the northern population (> = 15%), but above that indicated for the English and American population. Nevertheless, the values of the present study were higher than those in the latter populations, when children until seven years old were considered. The Freixo de Espada à Cinta population above 60 years had solar keratosis in 30.6%, a value three times higher than the previous decade (10.9%); reference values were not found. Contrary to the literature, an association was not established between phototype and solar keratosis. Cutaneous tumours were observed in 0.7% of the cases.

Adolescent↗

[Biliary cystadenoma and cystadenocarcinoma].

The authors present their experience with 5 biliary cystadenomas (BCA) and 1 cystadenocarcinoma (BCAC). BCA are rare but intriguing lesions of the liver for the possibility of the former to evolve into malignant lesion. Preoperative diagnosis is often difficult also at ultrasound and CT scan. The possibility of BCA and BCAC should be always ruled out in every cystic lesion of the liver. In every doubt lesion surgical exploration is indicated and at least a biopsy should be performed. The procedure of choice for BCA is radical resection, while palliative procedures may be justified only in poor risk patients.

Adult↗

[Major hepatectomies in liver neoplasms].

The development of major hepatic resective surgery during the last 50 years is due to a better knowledge of both hepatic regenerative capacity and intraparenchymal vascular and biliary anatomy. Two approaches of major hepatic resection have been described: 1) primary hilar approach; 2) primary transparenchymal approach. The authors review the indications of major hepatic resections in the treatment of hepatic tumors and discuss the advantages and the disadvantages of primary hilar and primary transparenchymal approaches, reviewing the data from the literature and the experience gained at the Clinica Chirurgica of the University of Verona from 1970 to 1989 of 289 major hepatic resections.

Hepatectomy↗

[Zuckerkandl tubercle of the thyroid gland (anatomo-surgical study: preliminary considerations)].

The presence of tubercle of Zuckerkandl (TZ) of the thyroid gland has been investigated in 20 specimens obtained from patients died from diseases not concerned to the cervical area. The project mas undertaken to elucidate the presence and the role of TZ as normal anatomical landmark. Special attempt has been paid to the relationships of the TZ with parathyroid gland and recurrent laryngeal nerve and the branches of the inferior thyroid artery. The tubercle was constantly found on the postero-medial surface of the thyroid lobe which showed constant relations with the branches of the inferior thyroid artery, superior parathyroid gland and recurrent laryngeal nerve. The outcomes of this preliminary report prove that TZ is an useful anatomical landmark to detect both superior parathyroid gland and laryngeal nerve in thyroid surgery.

Aged↗