Search PubMed⌕ Search

Biomedical subjects

A R Rosa

Publications and source records attributed to A R Rosa.

8 recordsLinked to original sources
PubMed2003

Prognostic value of p53 protein expression and vascular endothelial growth factor expression in resected squamous cell carcinoma of the esophagus.

The most common genetic alterations found in a wide variety of cancers are p53 tumor suppressor gene mutations. p53 appears to be a nuclear transcription factor that plays a role in the control of cell proliferation, apoptosis, and the maintenance of genetic stability. Angiogenesis is a critical process in solid tumor growth and metastasis. Vascular endothelial growth factor (VEGF), a recently identified growth factor with significant angiogenic properties, may be a major tumor angiogenesis regulator. Few studies have investigated the association between p53 and VEGF expressions and prognosis in esophageal carcinoma. Forty-seven specimens resected from patients with stage II and III squamous cell carcinoma (SCC) of the esophagus were studied using immunohistochemical staining. VEGF and p53 expressions were observed in 40% and 53% of the tumors, respectively. The p53 and VEGF staining statuses were coincident in only 21% of the tumors, and no significant correlation was found between p53 and VEGF statuses. No clinicopathologic factors were significantly correlated with p53 or VEGF expression. No significant association between p53 and VEGF expressions and poor prognosis was found. In conclusion, p53 and VEGF were not correlated with prognosis in patients with stage II and III SCC of the esophagus.

Carcinoma, Squamous Cell↗
PubMed2000

Histologic peripheral nerve changes in rats induced by deltamethrin.

Synthetic pyrethroid insecticides have been used in the last two decades largely because of their high activity as an insecticide and low mammalian toxicity. Some studies have demonstrated that these products, especially compounds with an alpha-cyano group, are toxic to the mammalian central nervous system (CNS) in acute intoxications. However, morphological studies are scarce. In the present work the histopathologic changes of the sciatic and tibial nerves of rats submitted to acute intoxication with the cyanopyrethroid deltamethrin were studied. For 3 consecutive days male Wistar rats received by oral gavage deltamethrin at a dose of 45 mg/kg body wt. On the 4th day fragments of sciatic and tibial nerves were studied by transmission electron microscopy (TEM) and teasing of individual nerve fibers. In addition, another group of rats were allowed to recover until the 10th day. Teasing of nerves of animals sacrificed on the 4th day revealed myelin ovoids, which are indicative of axonal damage. TEM demonstrated rare degenerated axons completely filled with organelles, in particular mitochondria, and with electron-dense lamellar bodies that resemble myelin figures. In addition, great cytoplasmic vacuolization caused by proliferation and dilation of the rough and smooth endoplasmic reticulum and Golgi apparatus was observed in some Schwann cells. No lesion was found 7 days after discontinuation of the treatment (group2). Since these histologic changes are transitory and scarce, the question arises: Are they related to the changes in NA(+), K(+)-ATPase activity or Na(+) channels caused by pyrethroid compounds?

Animals↗
PubMed1980

[Curricular reform].

Advocating the thesis that the planning of medical education must be oriented toward the articulastion of instruction with care, the authors note that the curricular reforms of the last 25 years, though reflected in the teaching-learning process, have led to no improvement in medical practice or in the health of the population. This failing, they assert, stems from the fact that these reforms begin and end within the educational institution itself, and ignore the interrelations between the education system and the user of the professional, and results in the production of physicians who are individualistic and of narrow vision. The article refers to the slight importance attached to the complementarity and interdependence of teaching and care work, and to the restriction of teaching to episodic contacts between specialized professors and groups of anonymous students, each in the limited confines of his own discipline, and the relegation of the student to the status of spectator and possible assistant in care work entrusted to him without any responsibility.

Brazil↗
PubMed1979

[Education and training of the general physician].

The authors of this paper, part of which was presented at the Seventh Pan American Conference on Medical Education (New Orleans, October 1978), recognize that training programs for general physicians should relate to the particular socioeconomic conditions and characteristics of the individual country and region. They propose that the general physician in developing countries be prepared in graduate courses to provide primary care, in order to give service immediately after graduation and because opportunities elsewhere for recent graduates are limited. After outlining new curriculum proposals for the general physicians, they argue against the establishment of departments of family medicine in Latin American medical schools. It is suggested that the general physician's training take place in outpatient clinics, health centers, and community and teaching hospitals, to make possible the integration of the medical education and medical care. Until such time when integration is achieved, the teaching hospital should afford medical education and care on a small scale, offering outpatient general clinics, nonspecialized services, and community health activities.

Brazil↗
PubMedDate not supplied

Survival and prognostic factors in patients with resected epidermoid oesophageal carcinoma.

To determine long-term survival of patients with thoracic oesophageal tumor who underwent resection, and to identify possible associated prognostic factors, 58 patients underwent oesophagectomy alone (group A) and 16 combined with neo-adjuvant chemoradiotherapy (group B). Univariate and multivariate analysis of prognostic factors were performed for age, depth of oesophageal wall tumour penetration, node involvement, type of resection, TNM stage and degree of tumour differentiation. Long-term survival rates at 1-5 years were 81% versus 89%; 56% versus 67%; 30% versus 67%; 12% versus 44%; and 0% versus 33% for group A and B, respectively (P = 0.0543, NS). Univariate analysis revealed only depth of invasion (P = 0.0076) and TNM stage (P = 0.0452) as isolated prognostic factors for long-term survival and multivariate analysis did not demonstrate any independent factor. Despite the small number of cases, neoadjuvant chemoradiotherapy seems to improve prognosis as well as to allow resection in a greater number of cases due to tumor downstaging.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Delayed cervical anastomosis of the esophagus for esophageal carcinoma.

BACKGROUND: The surgical approach for patients with advanced epidermoid esophageal carcinoma should provide an effective palliative effect with morbidity ratio as low as possible. Anastomotic leakage is a frequent complication and may be responsible for both early and late morbidity and, therefore, we assessed the role of delayed cervical esophagovisceral anastomosis technique in relation to the incidence of anastomotic complications. METHODS: Eight patients (Group 1) and 12 patients (Group 2) submitted to one-stage or two-stage operation, respectively, were selected by an intraoperative assessment by the surgeon, considering mainly tissue blood flow of the replacement organ after its placement in the cervical region. RESULTS: In Group 1 anastomotic dehiscence was observed in 37.5% of patients, while in Group 2 no cases of dehiscence occurred (p = 0.049). However, the postoperative mortality rate did not differ between the two groups (12.5% versus 0%, NS). CONCLUSION: When organ viability is uncertain, esophagovisceral anastomosis is best done by two-stage operation, since it decreases the incidence of anastomotic leak.

Adult↗