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1.
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619).  相似文献   
2.
A 20‐year‐old Congolese woman presented with presyncope, dyspnea, and anasarca. Past medical history was unremarkable. Echocardiography revealed a rare combination of giant right atrium (RA), a dilated and hypertrophied right ventricle, subvalvular pulmonary stenosis (subPS), severe tricuspid regurgitation (TR), pericardial effusion and what appeared to be a spontaneously closed ventricular septal defect (VSD). Cardiac Magnetic Resonance and Cardiac Computed Tomography confirmed the findings excluding the presence of intra‐cardiac and extra‐cardiac shunt and other associated congenital anomalies. The patient underwent subPS resection, right atrioplasty, and tricuspid annuloplasty. Multimodality approach facilitated the detection of the abnormalities and provided clarity when determining the optimal surgical strategy.  相似文献   
3.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
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5.
We demonstrate that a mixture of four recombinant dengue virus E polypeptides corresponding to the N-terminal region of the envelope protein from all serotypes substitutes for standard antigens in two immunoglobulin M enzyme-linked immunosorbent assay formats with 100% concordance, making these polypeptides a useful and accessible reagent for serological diagnosis of dengue in endemic countries.  相似文献   
6.
We report on a 26-year-old female affected by Noonan syndrome (NS), a congenital disorder characterized by various phenotypic features and congenital anomalies) associated with a variety of autoimmune diseases, including systemic lupus erythematosus, celiac disease, and Hashimoto thyroiditis. Autoimmunity is seldom described in NS and the association between this congenital disease and three autoimmune disorders has not been previously reported. Should the occurrence of autoimmune disorders in NS be confirmed, a relevant clinical and laboratory evaluation of NS patients should be performed in order to clarify whether the immune system involvement represents only an occasional event or is a feature of the disease.  相似文献   
7.
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours.  相似文献   
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The Pocone gold minings are situated in the Bento Gomes River Basin, at the border of the Pantanal of Mato Grosso. Gold-bearing quartz veins are removed from the subsoils, milled with water, centrifuged and the heavier fraction is subsequently mixed with mercury for gold separation. The gold mining activities caused a very intensive landscape change, threatening many environmental processes like sediment control and storage and recycling capacity of mercury. Cold Vapor Atomic Fluorescence System (CVAFS) was used to determinate total mercury in water, suspended material and sediments from Bento Gomes River, sampled monthly for 1 year. Apart from the fact that mercury concentrations are low in water and bottom sediments, they are slightly higher in relation to background levels measured in the area. The concentration in suspended material is also lower than other rivers with gold mining activities, but the floodplains of the Bento Gomes River act as mercury sinks. Therefore, the discharge of mercury into the Pantanal floodplain should be avoided, in spite of actual contamination of the system being very low.  相似文献   
10.
Eighty-six patients with locally advanced, high-grade soft tissue sarcomas of the extremities were studied prospectively in order to determine the efficacy of hyperthermic perfusion (HP) or hyperthermic antiblastic perfusion (HAP) as the first step of a combined multimodality therapy. The immediate response was evaluated in terms of tumor regression, and results confirmed the in vivo sensitivity of human sarcomas to the selective antineoplastic action of heat alone or combined with drugs (melphalan, actinomycin D, and cis-platinum). HAP has been shown to be simpler and safer than HP, and it is now currently routinely employed. As far as the long-term cure is concerned, all the patients have been evaluated for functional results, locoregional control, and survival, according to the different treatment schedules. The first clinical trials employed HP or HAP followed by delayed surgery alone. In 11 of 17 evaluable patients treated with HP, and in 17 of 29 treated with HAP, conservative surgery could be performed. A high incidence of locoregional relapse (24%) occurred, with low overall survival rates: 50.1% and 31.7% at 5 and 10 years after HP plus surgery, and 47.9% after HAP plus surgery at both 5 and 10 years. The protocol was, therefore, modified to include continuous intraarterial infusion of Adriamycin® (ADR) (17 patients) or radiotherapy (9 patients) before surgery. The results obtained thus far may be summarized as follows: (a) conservative surgery with functional limb-salvage was possible in all patients; (b) the percentage of locoregional failure decreased to approximately 12% after HAP + ADR infusion + excision, the 5- and 10-year overall survival rates both being 77.6 %, and the 5- and 10-year disease-free rates both being 57.8%; (c) no local recurrences occurred in the group treated with HAP + radiotherapy + excision with a 5-year overall survival rate of 71.5% and a 5-year disease-free rate of 50.4%. In conclusion, the combined multimodality approaches employed appear to have improved both functional results and long-term cure, even though these must be further confirmed on a larger series of patients.
Resumen Ochenta y seis pacientes con sarcomas de los tejidos blandos de las extremidades, de alto grado histológico, e invasión local avanzada fueron estudiados en forma prospectiva con el objeto de determinar la eficacia de la perfusión hipertérmica (PH) o la perfusión hipertérmica antiblástica (PHA) como primer paso dentro de una terapia combinada multimodal.La respuesta inmediata fue valorada en términos de la regresión tumoral, y los resultados confirmaron la sensibilidad in vivo de los sarcomas humanos a la acción antineoplásica selectiva del calor sólo o combinado con drogas (melfalán, actinomicina D, y cis-platino). La PHA ha demostrado ser más sencilla y más segura que la PH y actualmente es utilizada en forma rutinaria.En lo referente a curación a largo plazo, todos los pacientes han sido evaluados en cuanto a resultados funcionales, control locorregional, y supervivencia, de acuerdo a los diferentes programas terapéuticos.En los primeros ensayos clínicos se utilizó PH o PHA seguida de cirugía solamente. En 11 de 17 pacientes valorables tratados con PH y 17 con PHA, fue posible realizar cirugía conservadora. Se presentó una incidencia alta de relapso locorregional (24%), con tasas bajas de supervivencia global: 50.1% y 31.7% a 5 y 10 años con PH y cirugía, y 47.9% con PHA y cirugía tanto a 5 como a 10 años.El protocolo fue consecuentemente modificado para incluir una infusión intraarterial continua de Adriamicina® (ADR) (17 pacientes) o radioterapia (9 pacientes) antes de la cirugía.Los resultados logrados hasta el momento pueden ser resumidos así: (a) la cirugía conservadora con salvamento del miembro fue posible en la totalidad de los pacientes; (b) el porcentaje de falla locorregional disminuyó aproximadamente 12% después de PHA + infusión de ADR + resección, con supervivencias globales a 5 y 10 años de 77.6%, y tasas de estado libre de enfermedad a 5 y 10 años de 57.8%; (c) no se presentaron recurrencias locales en el grupo tratado con PHA + radioterapia + resección, con una tasa de supervivencia global a 5 años de 71.5% y una tasa de estado libre de enfermedad a 5 años de 50.4%.En conclusión, los aproches con terapia combinada multimodal empleados parecen haber mejorado tanto los resultados funcionales como las tasas de curación a largo plazo, aunque estos resultados aún deben ser reconfirmados en una serie mayor de pacientes.

Résumé Une étude prospective concernant 86 malades qui présentaient un sarcome des parties molles des membres de stade évolutif avancé a été entreprise pour déterminer l'efficacité de la perfusion hyperthermique ou de la perfusion hyperthermique antiblastique en tant que première étape d'un traitement à modalités multiples.La réponse immédiate a été appréciée en fonction de la régression tumorale. Les résultats ont confirmé la sensibilité in vivo des sarcomes humains à l'action antinéoplasique sélective de la chaleur employée isolemment ou combinée avec des drogues (melphalan, actinomycine D, et cis-platinum). La perfusion hyperthermique antiblastique s'est montrée plus simple et plus sûre que la perfusion hyperthermique, et de ce fait est devenue une méthode thérapeutique normalement employée.Pour apprécier l'action thérapeutique à long terme tous les malades ont été étudiés en tenant compte des résultats fonctionnels, du contrôle loco-régional, et de la survie obtenus selon les différentes thérapeutiques appliquées.Les premiers essais ont eu recours à l'hyperthermie thermique ou à l'hyperthermie thermique antiblastique suivie d'une intervention chirurgicale. Chez 11 des 17 malades traités par l'hyperthermie thermique, et chez 17 des 29 malades soumis à l'hyperthermie antiblastique le traitement chirurgical conservateur a pu être réalisé. Les résultats furent les suivants: fréquence importante des récidives loco-régionales (24%); taux global de survie bas: 50.1% et 31.7% à 5 ans et 10 ans après perfusion hyperthermique suivie de chirurgie, ce taux étant de 47.9% après perfusion hyperthermique antiblastique suivie de chirurgie à 5 ans et 10 ans.En fonction de ces résultats le protocole thérapeutique fut modifié en y ajoutant une transfusion intra-artérielle continue d'Adriamycine® (17 malades) ou de la radiothérapie (9 malades) avant l'intervention.Les résultats obtenus à ce jour peuvent se résumer ainsi: (a) la chirurgie conservatrice permettant de sauver un membre fonctionnel est toujours possible; (b) la poucentage d'échec régional décroit environ jusqu' à 12% après perfusion hyperthermique antiblastique associée à la perfusion d'Adriamycine® et l'excision, le taux global de survie à 5 ans et 10 ans étant de 77.6%, le taux d'absence de la maladie à 5 ans et 10 ans étant de 57.8%; (c) aucune récidive locale n'est survenue dans le groupe traité par perfusion hyperthermique antiblastique associé à la radiothérapie et à l'exérèse, le taux global de survie à 5 ans étant de 71.5% et le taux d'absence de la maladie à 5 ans étant de 50.4%.En conclusion le traitement qui a été employé associant plusieurs modalités thérapeutiques a entrainé une amélioration des résultats fonctionnels et de la cure à long terme encore que ce fait demande a été confirmé par une étude étendue à un plus grand mombre de malades.


Supported by Special Project Hyperthermia from the Italian Ministry of Health.  相似文献   
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