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P Santos

Publications and source records attributed to P Santos.

At least 19 recordsLinked to original sources
PubMed1997

Relatedness among Basques, Portuguese, Spaniards, and Algerians studied by HLA allelic frequencies and haplotypes.

HLA-A, -B, -DRB1, -DQA1, and DQB1 alleles were studied in Iberian and Algerian populations by serology and DNA sequence methodologies. The genetic and cultural relatedness among Basques, Spaniards, and paleo-North Africans (Berbers or Tamazights) was established. Portuguese people have also maintained a certain degree of cultural and ethnic-specific characteristics since ancient times. The results of the present HLA study in Portuguese populations show that they have features in common with Basques and Spaniards from Madrid: a high frequency of the HLA-haplotypes A29-B44-DR7 (ancient western Europeans), A2-B7-DR15 (ancient Europeans and paleo-North Africans), and A1-B8-DR3 (Europeans) are found as common characteristics. Portuguese and Basques do not show the Mediterranean A33-B14-DR1 haplotype, suggesting a lower admixture with Mediterraneans; Spaniards and Algerians do have this haplotype in a relatively high frequency, indicating a more extensive Mediterranean genetic influence. The paleo-North African haplotype A30-B18-DR3 present in Basques, Algerians, and Spaniards is not found in Portuguese either. The Portuguese have a characteristic unique among world populations: a high frequency of HLA-A25-B18-DR15 and A26-B38-DR13, which may reflect a still detectable founder effect coming from ancient Portuguese, i.e., oestrimnios and conios; Basques and Algerians also show specific haplotypes, A11-B27-DR1 and A2-B35-DR11, respectively, probably showing a relatively lower degree of admixture. A neighbor-joining dendrogram place Basques, Portuguese, Spaniards, and Algerians closer to each other and more separated from other populations. Genetic, cultural, geological, and linguistic evidence also supports the hypothesis that people coming from a fertile Saharan area emigrated towards the north (southern Europe, Mesopotamia, the Mediterranean Islands, and the North African coast) when the climate changed drastically to hotter and drier ca 10 000 years B.C.

Algeria↗
PubMed1996

Serum antibody reactivity to recombinant mig and whole cell antigens in Mycobacterium avium infection.

Mycobacterium avium is a significant opportunistic pathogen in immunocompromised patients. Moreover, the prevalence of infections in patients without known predisposing conditions has also been increasing in recent years. Patients would greatly benefit from early diagnosis of disseminated infection. Serodiagnostic tests have already been promising in tuberculosis and immunocompetent patients but studies in HIV-infected patients and humoral response to M. avium antigens resulted in conflicting data. We have evaluated the use of the phagocytosis-induced MIG protein of M. avium as a diagnostic antigen. Serum antibody levels of M. avium-infected, HIV-negative patients were significantly elevated for the recombinant MIG (p < 0.001) and also for M. avium whole-cell antigens (p < 0.025) as compared to controls. In contrast, HIV-infected patients with disseminated M. avium infection demonstrated also elevated levels of antibody for the whole-cell antigen (p < 0.00001) but a decreased reactivity for the MIG antigen (p < 0.007). The recombinant antigen proved to have no cross-reactivity with M. tuberculosis antigens as antibody levels were decreased in tuberculosis patients (p < 0.001). Therefore, a simultaneous serological test using recombinant MIG and the whole cell antigens might be helpful in the sometimes problematic diagnosis of M. avium infections in patients without predisposing conditions.

Antibodies, Bacterial↗
PubMed1994

Neoadjuvant chemotherapy with cisplatin and 5-fluorouracil, both in continuous 96-hour infusion, in the treatment of locally advanced head and neck cancer.

In this study, 79 patients with locally advanced head and neck cancer were treated with induction chemotherapy. Cisplatin, 25 mg/m2, and 5-fluorouracil (5-FU), 1000 mg/m2, were employed, both of them in 24-hour continuous infusion over 96 hours, four cycles. The patients later underwent surgery and/or radiation therapy. The response to chemotherapy was 49%: of the complete responses (CR), 56% were histological; 29% were partial responses (PR). With the administration of the fourth cycle, CR increased from 30% to 49%. Once the complete treatment had been finished, 75% of CR and 5% PR were achieved. With a maximum follow-up period of 44 months, overall survival stands at 50%.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

[Melanoma and pregnancy].

In spite of being a rare form of neoplasia, melanoma is the ones which occur most frequently in pregnancy. Pregnancy does not seem to aggravate the prognosis. However, the authors present the case of a woman suffering from melanoma, in which the intercurrence of pregnancy led to the development of the disease. After 32 weeks of pregnancy a living foetus was born without any symptoms of the disease, thus proving the low incidence of foetal metastatic lesions.

Adult↗
PubMed1992

Configuration of immunoglobulin and T cell receptor beta and gamma genes in acute myeloid leukaemia: pitfalls in the analysis of 40 cases.

AIMS: To evaluate the overall incidence of immunoglobulin (Ig) and T cell receptor (TCR) beta and gamma gene rearrangements in a series of 40 cases of acute myeloid leukaemia (AML) and to determine whether structural modifications of these genes could be correlated with the abnormal expression of lymphoid markers in malignant cells. METHODS: All cases were classified according to the criteria of the FAB group and immunophenotyped with a panel of monoclonal antibodies reactive with myeloid and lymphoid differentiation antigens. DNA analysis was performed by the method of Southern using probes for the Ig JH, TCR-C beta 1, and TCR-J tau 1 regions. RESULTS: Phenotypic analysis showed that in addition to myeloid markers, 10 cases expressed lymphoid antigens: CD7 in seven (of which three were TdT positive, one CD2 positive, and one CD19 positive) and CD19 in three. Southern blot analysis showed that bands with sizes different from the germ line control were present in the TCR beta genes in 11 cases: in six of 30 with pure myeloid phenotype and in five of 10 of those expressing lymphoid markers. A close observation of the size and patterns of those bands, however, showed that they could be artefactual. Indeed, further analysis showed that they were either due to resistant Eco RI/Hind III sites at the beta locus or to plasmid contamination. Rearranged genes were eventually found in only two of the 40 cases: at the Ig JH region in one of the 30 with pure myeloid phenotype (3.3%) and at the TCR gamma genes in one of 10 with lymphoid markers (10%). CONCLUSIONS: These observations showed that Ig/TCR gene rearrangements were rare in this AML series (overall incidence of 5%) and that they were not significantly more common in cases with aberrant expression of lymphoid markers. The size and pattern of the potential non-germline bands that can be found in these loci must be carefully evaluated.

Acute Disease↗
PubMed1991

Hemodynamic changes during whole bronchoalveolar lavage in two cases of pulmonary alveolar proteinosis.

Five whole bronchoalveolar lavages were performed in 2 patients with pulmonary alveolar proteinosis with continuous monitoring of mixed venous and arterial oxygen saturation. Hemodynamic parameters and gas-exchange status were measured during the different phases of the lavage. In the phase of filled lung, a significant increase of arterial partial pressure (PaO2) and arterial saturation of oxygen were observed, secondary to a decrease in the intrapulmonary shunt. The mean pulmonary arterial pressure, pulmonary vascular resistances and cardiac index were higher during the filling of the lung as compared to the controls. During the empty lung phase, although PaO2 decreased (without reaching statistical significance), due to an increase in the intrapulmonary shunt, the increase in cardiac output during this phase left the oxygen delivery (DO2) unchanged.

Adult↗
PubMed1983

[Indications for the surgical correction in patients with transposition of the great arteries, intact interventricular septum and organic or functional obstruction of the outflow tract of the left ventricle. Analysis of 53 cases operated on by the Mustard technic].

Between January 1965 and December 1979, in our Unit 53 patients underwent Mustard's operation for TGA, intact ventricular septum and LVOTO. There were 35 males and 18 females, ranging in age from 27 days to 12 years (mean = 26 months) and in weight from 3.7 to 26 kg (mean = 9.6 Kg). Twenty-one infants had undergone previous palliative procedures. The degree of LVOTO was mild in 26 cases, moderate in 10 and severe in 17 patients. In 28 cases no distinct anatomical obstructions were identified. In the other 25 patients the obstruction occurred at various level and it was determined by several anatomical structures. Subvalvular fibromuscular narrowing, redundant mitral valve, valvular stenosis and subvalvular fibrous shelf were the commonest forms encountered. The LVOTO was managed in several different ways. In 28 patients in whom the gradient was judged to be functional, no surgical intervention at the level of the LVOT was attempted. In 8 cases, all operated on at the beginning of this experience, an anatomic obstruction was present but was considered too difficult to be resected and, therefore, was left untreated. In 9 patients the LVOT was inspected either through the pulmonary valve or from below, through a left ventriculotomy. Pulmonary valvotomy was carried out in 5 of these cases, resection of the subvalvular fibrous shelf in 3 and subvalvular fibromuscular tunnel resection in 1. In 6 patients a left ventricle to pulmonary artery conduit was used to bypass the obstruction. A fibromuscular tunnel type of obstruction was present in 5 of these cases, while in one the obstruction was mainly due to a redundant mitral valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1983

[Indications for the surgical correction of patients with transposition of the great arteries associated with an interventricular defect. Analysis of 98 cases operated on using the Mustard technic].

At the Hospital for Sick Children, London, between Jan. 1965 and Jan. 1980, 98 patients, ranging in age from 22 days to 20.8 years (mean = 29.6 months), with a clinical diagnosis of transposition of the great arteries (TGA) associated with a ventricular septal defect (VSD) found at cardiac catheterization, underwent Mustard procedure at the atrial level, whether or not associated with the VSD closure. Twenty-nine other patients, with irreversible obstructive pulmonary vascular disease in whom a "palliative" Mustard was performed, have been excluded from this report. At operation, in 8 cases, the VSD was found to have closed spontaneously during the interval between the cardiac catheterization and the surgical repair, while, in 13 patients, the VSD was judged to be too small to influence the hemodynamic results and, accordingly, was left open. In 35 cases the VSD was closed with mattress stitches buttressed with dacron pledgets and in 42 patients a dacron patch was used. The defects were accessible through the tricuspid valve in all but 10 cases. There were 24 early deaths (24%) and these did not correlate either with the year of operation or with the age at the time of operation. The mortality rate was higher in the cases who had required previous pulmonary artery banding (37%), than in those who had not (21.5%), but this difference was not statistically significant. The early results were related to the size of the VSD. In the 21 patients in whom the VSD was partially or completely closed, the early mortality was 9.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1981

Deliberate hypotension and anesthetic requirements of halothane.

Following determination of minimum alveolar anesthetic concentration (MAC) of halothane during normotension, 18 dogs were divided into three groups. Dogs in each group then received either pentolinium, trimethaphan, or sodium nitroprusside, and mean arterial pressure was decreased to 60% of control values for 1 hour. The MAC of halothane was determined during hypotension and then arterial pressure was returned to control values and MAC was redetermined at normotension. The MAC of halothane decreased significantly during hypotension in all three groups: in the pentolinium group from a control MAC of 1.2 +/- 0.14 (SEM) to a MAC of 0.7 +/- 0.11 during hypotension, in the trimethaphan group from a control MAC of 1.02 +/- 0.06 to a MAC of 0.72 +/- 0.07 during hypotension, and in the nitroprusside group from a control MAC of 1.02 +/- 0.07 to a MAC of 0.73 +/- 0.07 during hypotension. Upon return of mean arterial pressure to normotensive levels, MAC of halothane returned to control values in dogs given pentolinium and trimethaphan, but in dogs given nitroprusside MAC remained at the hypotensive value. There was no correlation between the changes in MAC and carotid blood flow or cardiac index. These data indicate that anesthetic requirements decrease during deliberate hypotension irrespective of the drug used to produce hypotension.

Anesthesia, Inhalation↗
PubMedDate not supplied

[Deep lobe parotid tumors].

Tumours of the deep lobe, the section of the parotid located within the plane of the facial nerve, are not very frequent. Their diagnosis is difficult and seldom early, and their treatment involves complex technical problems. They evolve in one of two forms: as a tumour of the parapharyngeal space, or as a "dumb-bell" tumour with protrusion in the preauricular zone. Typical cases of both topographical possibilities are presented in this paper.

Adenoma, Pleomorphic↗