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21.
22.
Claudio Gustavo Stefanoff Rocío Hassan Ana Carolina Gonzalez Luiz Ant?nio B Andrade Daniel G Tabak Sérgio Romano Ilana R Zalcberg 《Diagnostic molecular pathology》2003,12(2):79-87
We herein present a technical strategy to optimize DNA isolation from paraffin-embedded tissue (PET). This includes the choice of adequate buffers for proteinase K digestion and multiplex PCR amplifications for assessing the appropriateness of DNA extracts for subsequent PCR assays for detecting clonality. We found that the association of proteinase K digestion in nonionic buffer and subsequent extract dilutions accounted for 79% of successful amplifications. A final efficiency of 88% was achieved by additional organic extractions and/or re-extractions. Comparisons were carried out with control DNA extracts from fresh samples to assess the efficiency of each clonality assay. Immunoglobulin CDRIII rearranged region amplification was more efficient for pregerminal center B-cell lymphomas in contrast to CDRII rearrangement detection, which was more effective for germinal and postgerminal lymphomas. T-cell clonality detection by TCRgamma PCR was less efficient in PET samples than in fresh tissues showing that DNA integrity is more critical for TCR than for IGH amplification. Two inconclusive cases without phenotypic markers and two other atypical lymphoproliferations masked by reactive T cells were diagnosed as plasmablastic lymphomas and as monoclonal B-proliferations, respectively, due to IGH rearrangements. 相似文献
23.
Gil LH Alves FP Zieler H Salcedo JM Durlacher RR Cunha RP Tada MS Camargo LM Camargo EP Pereira-da-Silva LH 《Journal of medical entomology》2003,40(5):636-641
Studies on seasonal anopheline fauna variation were performed in two distinct settlements in the State of Rond?nia, Brazil: one at the Madeira River banks (Portuchuelo) with stable native Amazonian population; the other at an inland lumber-extracting farm (Urupá) in dry land, in which adults are mostly migrants. During a 6-yr period (1994-2000), 8,638 adult anophelines were collected: 2,684 in Urupá and 5,954 in Portuchuelo. Anopheles darlingi represented >95% of total mosquitoes caught. Dissection of 4,424 A. darlingi females yielded a very low sporozoite infection index below 0.1%. Oocysts were found in both localities in approximately 0.1% of dissected mosquitoes. Determination of the hour biting rates disclosed seasonal variations in both localities. However, in Portuchuelo, mosquito density peaked at the acme of the rainy season, whereas at Urupá it peaked in the dry season. The increase in mosquito density and incidence of malaria cases were coincident. The high mosquito densities observed in the riverine settlement of Portochuelo sector B, which permits evaluation in > 10,000 mosquitoes' bites/person/year, could explain, in spite of the low mosquito's infection index, the previously described development of natural immunity in the local population that is not observed in the dry land agroindustrial settlement of Urupá. 相似文献
24.
Superantigens induce clonal deletion of reactive T cells in the thymus and clonal deletion and anergy in the periphery of euthymic mice. In this report we have assessed the ability of Staphylococcal enterotoxin B (SEB) to induce peripheral tolerance in nude mice reconstituted with normal, syngeneic T cells. Immunization of reconstituted nude mice with SEB resulted in lethal toxic shock in a large fraction of the animals. Such lethality was never observed in the normal donor mouse strain. Analysis of lymphokine production in response to SEB showed that reconstituted nude mice produced higher levels of interleukin-2 and tumor necrosis factor-α, but lower levels of interleukin-4, than euthymic control mice. Furthermore, SEB was unable to promote either clonal elimination or induction of anergy in the SEB-responsive peripheral T cells, despite the fact that reconstituted nude mice did produce high levels of corticosterone upon treatment with SEB. These results imply a lack of control over immune responses to superantigen in T cell-reconstituted athymic mice. 相似文献
25.
Câmara Vd Filhote MI Lima MI Alheira FV Martins MS Dantas TO Luiz RR 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(2):149-158
The main objective of this study was to promote the evaluation of an educational method to identify health risks among adolescents exposed to mercury by their work in gold mining production.The project was carried out with adolescents from a public school from the District of Monsenhor Horta, Municipality of Mariana, state of Minas Gerais. Statistical evaluation of the results revealed a significant increase in the amount of correct answers between the first and fifth stage concerning the definition of work accidents and its importance in relation to work-related diseases, accidents on route to and from the work place and violence at work site itself. 相似文献
26.
Syringe liposculpture: A two-year experience 总被引:1,自引:0,他引:1
Luiz S. Toledo M.D. 《Aesthetic plastic surgery》1991,15(1):321-326
Syringe liposcupture is a method that combines two relatively new techniques of plastic surgery: syringe liposuction and fat grafting. We can reshape the face and the body by removing localized fat deposits and reinjecting this fat where needed. When we do not reinject, we call the technique reduction liposculpture. In 1989 we introduced a new technique—superficial syringe liposculpture—to treat patients with flaccid skin, superficial irregularities or depressions, cellulite, and liposuction sequelae. The technique combines syringe liposculpture, superficial liposuction, and our method of treating skin irregularities by breaking the fibrous adherences and injecting fat superficially. 相似文献
27.
Luiz A Benvenuti Francisco O S Fran?a Kátia C Barbaro José R Nunes Jo?o L C Cardoso 《Toxicon》2003,42(3):331-334
A 36-year old woman was bitten on the left ankle by a Bothrops jararacussu, and died 45 min after the bite. At necropsy, there were local signs of envenoming with haemorrhage, thrombosis and necrosis of the subcutaneous and muscular tissue. Multiple fibrin and platelet thrombi were found in the microcirculation of the heart and lungs, suggesting the occurrence of disseminated intravascular coagulation. Pulmonary haemorrhage probably secondary to the action of haemorrhagins, consumption coagulopathy and disseminated intravascular coagulation was the immediate cause of death. Intravenous inoculation of the venom could have occurred in the present case, which would explain the rapid onset of coagulation disorders, haemorrhage and death. 相似文献
28.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
29.
BNP and ANP as diagnostic and predictive markers in heart failure with left ventricular systolic dysfunction. 总被引:3,自引:0,他引:3
Luiz Menezes Falc?o Fausto Pinto Luciano Ravara Peter Adriaan van Zwieten 《Journal of the renin-angiotensin-aldosterone system》2004,5(3):121-129
BACKGROUND: The prevalence of chronic heart failure (CHF) with systolic dysfunction is increasing. Plasma natriuretic peptides have been envisaged as diagnostic and predictive markers. AIMS: To investigate the relationship between the levels of B-type natriuretic peptide (BNP) and A-type natriuretic peptide (ANP) and the clinical and functional parameters of CHF in outpatients with CHF at baseline, compared with normal healthy controls; to find out the differences in a randomised controlled trial between patients treated with an angiotensin-converting enzyme (ACE) inhibitor, captopril, or an angiotensin receptor blocker (ARB), irbesartan. These differences were assessed throughout the six-month treatment period and at the sixth month. METHODS: Plasma BNP (pmol/L) and ANP (pmol/L) were determined in 68 hypertensive patients with dilated cardiomyopathy, NYHA class III-IV and ejection fraction (EF) < or = 40%, and in 26 normal controls. Statistical analysis for BNP and ANP was done by Students t-test. The patient group was randomly subdivided into two subgroups of 34 patients, each treated with either an ARB, irbesartan, or an ACE inhibitor (ACE-I), captopril. BNP and ANP were measured in both subsamples and correlated with clinical, functional and neurohormonal parameters throughout a follow-up period of six months and at the sixth month. RESULTS: The mean EF in the patient sample was 33.43+/-6.52% and in the controls was 61.96 +/-3.53% (p=0.000). The mean BNP (pmol/L) in patients was 44.78+/-54.36 and in the controls was 7.12+/-8.28 (p=0.000) and the mean ANP (pmol/L) was 30.32+/-25.97 in patients and 11.18+/-7.92 in controls (p=0.000). A statistically significant difference was found between patients and healthy controls. Significant correlations were found between natriuretic peptides and EF. Between the baseline phase and the sixth month, BNP and ANP decreased significantly in the ARB group. At the sixth month, both BNP and ANP were lower in the ARB group. Evidence of clinical benefit was found with both ARB or ACE-I treatment throughout the six months, with patients moving from classes III and IV to class II NYHA. Improvement of EF was also found, with transition of patients with lower EF (even <30%) to higher values. EF was higher in the ARB group at the sixth month. CONCLUSIONS: BNP and ANP can be useful diagnostic tools in hypertensive CHF patients with moderate-to-severe LV dysfunction. The decrease in BNP and ANP in the ARB group throughout six months, as well as the lower value at the sixth month, suggest a prognostic value of these parameters. 相似文献