6 resultados para Biomechanical phenomena
Resumo:
Background: Barnacles are a type of seafood with worldwide distribution and abundant along the shores of temperate seas. They are particularly appreciated and regularly consumed in Portugal as well as in Spain, France and South America, but barnacle allergy is a rare condition of which there is only one reference in the indexed literature. The molecular allergens and possible cross-reactivity phenomena implicated (namely with mites) have not been established. Objective: To demonstrate the IgE-mediated allergy to barnacle and to identify the proteins implicated as well as possible cross-reactivity phenomena with mites. Methods: We report the clinical and laboratory data of five patients with documented IgE-mediated allergy to barnacle. The diagnosis was based on a suggestive clinical history combined with positive skin prick tests (SPT) to barnacle – prick to prick method. Two barnacle extracts were prepared (raw and cooked barnacle) and sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) and IgE-immunoblotting were performed. An immunoblotting inhibition assay with Dermatophagoides pteronyssinus was also done in order to evaluate cross-reactivity. Results: All patients had mite-related asthma and the allergic rhinoconjunctivitis; they all experienced mucocutaneous symptoms. All of them had positive SPT to barnacle, and the immunoblotting showed several allergenic fractions with a wide molecular weight range (19 – 94 kDa). The D. pteronyssinus extract inhibited several IgE-binding protein fractions in the barnacle extract. Conclusions: We describe five patients with IgE-mediated barnacle allergy. We also describe a group of IgEbinding+ proteins between 30 and 75 kDa as the allergenic fractions of this type of Crustacea. Cross-reactivity with D. pteronyssinus was demonstrated in two cases.
Resumo:
INTRODUCTION: Transthoracic echocardiography is the method of choice for the diagnosis of cardiac myxomas, but the transesophageal approach provides a better definition of the location and characteristics of the tumor. The authors review their thirteen years' experience on the echocardiographic diagnosis of this pathology. METHODS: From 1994 to 2007, 41 cardiac tumors were diagnosed in our echocardiographic laboratory, of which 27 (65.85%) were cardiac myxomas. The exams and the patients' clinical files were retrospectively reviewed. RESULTS: Of the 27 patients, 22 (81.5%) were female, with a mean age of 62.1 +/- 13.6 years (25-84 years). The predominant clinical features were due to the obstruction caused by the tumor in more than two thirds of the patients, followed by constitutional symptoms in one third and embolic events in 30%. In the lab results, anemia was found in three patients and elevated sedimentation rate and CRP in two. In two patients the myxoma was found by chance. All the cases were of the sporadic type, although we found a prevalence of thyroid disease of 14% (4 patients). All patients underwent urgent surgical resection except one, in whom surgery was refused due to advanced age and comorbidities. The myxomas followed a typical distribution with 24 (88.8%) located in the left atrium, 18 of them attached to the atrial septum (AS) and two to the mitral valve. In one patient, the tumor involved both atria. The other two cases originated in the right atrium at the AS. Embolic phenomena were more frequent in small tumors (p = 0.027) and in those with a villous appearance (p = 0.032). Obstructive manifestations were associated with larger tumors (p = 0.046) and larger left atria (p = 0.048). In our series, there were no deaths during hospitalization or in the follow-up period of 5.2 +/- 3.7 years in 19 patients. There were two recurrences, both patients being successfully reoperated. CONCLUSION: Myxoma is the most common cardiac tumor. Transesophageal echocardiography provides excellent morphologic definition, aiding in diagnosis and follow-up. Most clinical manifestations are obstructive and are associated with larger tumors. Small tumors with a friable appearance have a higher chance of embolization. Surgical resection is usually curative and the long-term prognosis is excellent.
Resumo:
The autonomic nervous system (ANS) is known to be an important modulator in the pathogenesis of paroxysmal atrial fibrillation (PAF). Changes in ANS control of heart rate variability (HRV) occur during orthostatism to maintain cardiovascular homeostasis. Wavelet transform has emerged as a useful tool that provides time-frequency decomposition of the signal under investigation, enabling intermittent components of transient phenomena to be analyzed. AIM: To study HRV during head-up tilt (HUT) with wavelet transform analysis in PAF patients and healthy individuals (normals). METHODS: Twenty-one patients with PAF (8 men; age 58 +/- 14 yrs) were examined and compared with 21 normals (7 men, age 48 +/- 12 yrs). After a supine resting period, all subjects underwent passive HUT (60 degrees) while in sinus rhythm. Continuous monitoring of ECG and blood pressure was carried out (Task Force Monitor, CNSystems). Acute changes in RR-intervals were assessed by wavelet analysis and low-frequency power (LF: 0.04-0.15 Hz), high-frequency power (HF: 0.15-0.60 Hz) and LF/HF (sympathovagal) were calculated for 1) the last 2 min of the supine period; 2) the 15 sec of tilting movement (TM); and 3) the 1st (TT1) and 2nd (TT2) min of HUT. Data are expressed as means +/- SEM. RESULTS: Baseline and HUT RR-intervals were similar for the two groups. Supine basal blood pressure was also similar for the two groups, with a sustained increase in PAF patients, and a decrease followed by an increase and then recovery in normals. Basal LF, HF and LF/ HF values in PAF patients were 632 +/- 162 ms2, 534 +/- 231 ms2 and 1.95 +/- 0.39 respectively, and 1058 +/- 223 ms2, 789 +/- 244 ms2 and 2.4 +/- 0.36 respectively in normals (p = NS). During TM, LF, HF and LF/HF values for PAF patients were 747 +/- 277 ms2, 387 +/- 94 ms2 and 2.9 +/- 0.6 respectively, and 1316 +/- 315 ms2, 698 +/- 148 ms2 and 2.8 +/- 0.6 respectively in normals (p < 0.05 for LF and HF). During TF1, LF, HF and LF/ HF values for PAF patients were 1243 +/- 432 ms2, 302 +/- 88 ms2 and 7.7 +/- 2.4 respectively, and 1992 +/- 398 ms2, 333 +/- 76 ms2 and 7.8 +/- 0.98 respectively for normals (p < 0.05 for LF). During TF2, LF, HF and LF/HF values for PAF patients were 871 +/- 256 ms2, 242 +/- 51 ms2 and 4.7 +/- 0.9 respectively, and 1263 +/- 335 ms2, 317 +/- 108 ms2 and 8.6 +/- 0.68 respectively for normals (p < 0.05 for LF/HF). The dynamic profile of HRV showed that LF and HF values in PAF patients did not change significantly during TM or TT2, and LF/HF did not change during TM but increased in TT1 and TT2. CONCLUSION: Patients with PAF present alterations in HRV during orthostatism, with decreased LF and HF power during TM, without significant variations during the first minutes of HUT. These findings suggest that wavelet transform analysis may provide new insights when assessing autonomic heart regulation and highlight the presence of ANS disturbances in PAF.
Resumo:
The therapeutic approach to severe pulmonary arterial hypertension (PAH), whether primary or secondary to connective tissue disorders, thromboembolic phenomena or congenital heart disease with Eisenmenger syndrome, has evolved in recent years following the introduction of selective pulmonary vasodilators, including prostacyclin analogs and endothelin receptor antagonists. AIM: To correlate three different endpoints (6-minute walk test, Tei index and peak tricuspid regurgitation velocity by Doppler echocardiographic study) during follow-up of PAH patients under selective vasodilator therapy. METHODS: Eleven patients (9 female, age 42 +/- 18 years) with severe PAH (> or = 65 mmHg), 64% with Eisenmenger syndrome, in NYHA class > or = II, were assessed during a follow-up of 11 +/- 8 months. Eight patients were already under therapy with iloprost or bosentan. RESULTS: There was no correlation between the three endpoints before and after therapy as assessed by Pearson's correlation coefficient. There was, however, an improvement in all of them after selective vasodilatory therapy. CONCLUSION: Therapeutic response can be accurately measured by the traditional endpoint (6-minute walk test) or by echocardiographic endpoints. However, the lack of correlation between them excludes their use as alternatives in patient follow-up.
Resumo:
Based on a case of a patient with angiosarcoma (AS) of the right atrium with superior vena cava syndrome associated with urticaria and polyarthralgias, who died soon after surgery, the authors present a brief review of the subject of cardiac AS, an extremely rare pathology, usually diagnosed late due to its non-specific symptomatology. Several topics are discussed, including mechanisms of clinical manifestations caused by blood flow obstruction and valve dysfunction, local invasion with arrhythmias and pericardial effusion, embolic phenomena and constitutional symptoms. Imaging and histopathologic methods of diagnosis are considered, as well as references to cytogenetic analysis. Surgery is the first treatment choice, but heart AS are frequently not completely resectable and concomitant metastases at the time of surgery are common, both usually leading to a dismal prognosis. Chemotherapy, radiotherapy and even heart transplantation do not substantially improve the survival of these patients. Urticaria is not generally assumed by most authors to be associated with malignancy, but there are rare reports of its association with some malignant tumors.
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OBJECTIVE: The adjusted effect of long-chain polyunsaturated fatty acid (LCPUFA) intake during pregnancy on adiposity at birth of healthy full-term appropriate-for-gestational age neonates was evaluated. STUDY DESIGN: In a cross-sectional convenience sample of 100 mother and infant dyads, LCPUFA intake during pregnancy was assessed by food frequency questionnaire with nutrient intake calculated using Food Processor Plus. Linear regression models for neonatal body composition measurements, assessed by air displacement plethysmography and anthropometry, were adjusted for maternal LCPUFA intakes, energy and macronutrient intakes, prepregnancy body mass index and gestational weight gain. RESULT: Positive associations between maternal docosahexaenoic acid intake and ponderal index in male offspring (β=0.165; 95% confidence interval (CI): 0.031-0.299; P=0.017), and between n-6:n-3 LCPUFA ratio intake and fat mass (β=0.021; 95% CI: 0.002-0.041; P=0.034) and percentage of fat mass (β=0.636; 95% CI: 0.125-1.147; P=0.016) in female offspring were found. CONCLUSION: Using a reliable validated method to assess body composition, adjusted positive associations between maternal docosahexaenoic acid intake and birth size in male offspring and between n-6:n-3 LCPUFA ratio intake and adiposity in female offspring were found, suggesting that maternal LCPUFA intake strongly influences fetal body composition.