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1.
IEEE Trans Inf Technol Biomed ; 12(1): 55-65, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18270037

RESUMO

It has been shown that the accuracy of mammographic abnormality detection methods is strongly dependent on the breast tissue characteristics, where a dense breast drastically reduces detection sensitivity. In addition, breast tissue density is widely accepted to be an important risk indicator for the development of breast cancer. Here, we describe the development of an automatic breast tissue classification methodology, which can be summarized in a number of distinct steps: 1) the segmentation of the breast area into fatty versus dense mammographic tissue; 2) the extraction of morphological and texture features from the segmented breast areas; and 3) the use of a Bayesian combination of a number of classifiers. The evaluation, based on a large kappa = 0.81 and 0.67 for the two data sets) between automatic and expert-based Breast Imaging Reporting and Data System mammographic density assessment.


Assuntos
Mama/patologia , Mamografia , Automação , Teorema de Bayes , Sistemas de Gerenciamento de Base de Dados , Feminino , Humanos
2.
Eur J Surg Oncol ; 34(2): 191-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17475440

RESUMO

AIM: To evaluate the influence of distinguishing between well and poorly differentiated nonfunctioning neuroendocrine pancreatic carcinomas (PC). METHOD: Six well differentiated and 11 poorly differentiated nonfunctioning neuroendocrine PC were retrospectively analyzed for differences and compared with 340 ductal PC. RESULTS: 1. There was no difference in pT categories between well differentiated and, poorly differentiated nonfunctioning neuroendocrine PC and ductal PC. 2. The rate of the pN1 category was lower in well differentiated lesions (20%) than in poorly differentiated lesions (66%) and in the ductal PC group (75%). 3. The outcome of patients with R0 resections was significantly better for well differentiated neuroendocrine PC with all patients alive than for poorly differentiated ones and for ductal PC (5-year survival rate 0% and 18%, respectively). 4. The outcome following R1/R2 resections for poorly differentiated neuroendocrine PC tended to be similar than for ductal PC (1-year survival rate 20% vs. 33%). 5. There was no difference in mean survival time (9 months) between poorly differentiated lesions and ductal PC after palliative procedures. CONCLUSIONS: The better outcome of surgical treatment of nonfunctioning neuroendocrine PC vs. that of ductal PC was confined to well differentiated neuroendocrine lesions. For poorly differentiated lesions the outcome was as poor as for ductal PC. These results underscore the importance to distinguish between well and poorly differentiated nonfunctioning neuroendocrine PC.


Assuntos
Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/cirurgia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Adulto , Idoso , Biópsia por Agulha , Carcinoma Neuroendócrino/mortalidade , Carcinoma Ductal Pancreático/mortalidade , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pancreatectomia/métodos , Neoplasias Pancreáticas/mortalidade , Probabilidade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Fatores de Tempo
3.
Actas Urol Esp ; 31(3): 262-9, 2007 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-17658155

RESUMO

INTRODUCTION: Nocturia is the main cause of insomnia or sleep interruption in adult men, which has a negative impact on daily activities, quality of life (QoL) and quality of sleep (QoS). The assessment of nocturia and its impact on QoL and QoS in patients suffering from benign prostatic hyperplasia (BPH) has been poor in terms of clinical research, moreover there is a lack of specific methods to assess this impact. OBJECTIVES: The objectives of BPH treatment should include the improvement of patient's QoL by controlling both diurnal and nocturnal symptoms. In order to assess how nocturia affects QoL and also QoS, some specific tools, such as N-QoL questionnaire or the number of Hours of Undisturbed Sleep (HUS), have been recently developed. Therefore, it would be interesting to assess how nocturia reduction due to LUTS/BPH treatment can impact on some objective parameters such as HUS and also how nocturia reduction improves QoS and QoL. This assessment should be developed during the application of pharmacological treatments in clinical practice by means of these specific tools. With the aim of tackling nocturia as an urologic problem in patients with LUTS/BPH, as well as knowing the physiology of sleep and the effect of nocturia on the sleep and QoL, a meeting of expert urologists, that gathered about fifty specialists of all around Spain, was held in Madrid. This article presents the main ideas and concepts exposed in this meeting. CONCLUSIONS: Nocturia is a symptom with a high prevalence in older patients with STUI/BPH. The PreNoc study has showed a Nocturia prevalence in Spain of 83% in patients > or =60 years old diagnosed of BPH. Nocturia is the most bothersome symptom in patients with STUI/BPH.


Assuntos
Noctúria/etiologia , Hiperplasia Prostática/complicações , Qualidade de Vida , Sono , Humanos , Masculino , Terminologia como Assunto
4.
Ann Biol Clin (Paris) ; 63(5): 535-9, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16230292

RESUMO

We report a case of primary plasma cell leukaemia, with an absolute count of plasma cells of 53 Giga/L, diagnosed in a 83-year-old woman. The patient's condition improved, with no circulating plasma cells after 3 weeks of treatment, in response to the combination of thalidomide and dexamethasone administered for 5 days followed by thalidomide alone. The clinical presentation, the morphological, flow cytometric and pathophysiological characteristics of the plasma cell leukaemia and the treatment are summarised in this paper.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Leucemia Plasmocitária/diagnóstico , Talidomida/uso terapêutico , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Dexametasona/uso terapêutico , Feminino , Humanos , Leucemia Plasmocitária/tratamento farmacológico
6.
Leuk Res ; 27(5): 405-11, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12620292

RESUMO

This multicenter randomized phase III study was designed to compare the efficacy and toxicity of IFN alpha-2c (3.5 MU/d) in combination with either araC (10 mg/m(2) d1-10) or hydroxyurea (HU: 25 mg/kg per day) in newly diagnosed CML patients. A total of 114 patients were randomized. Following a median observation period of 36 (range 1-73) months the major cytogenetic response rates were 25 and 27% and the 4-year survival probabilities 62.5 and 63% for the araC and HU group, respectively. While the overall toxicity profile was comparable between both groups, patients in the HU arm exhibited a slightly higher degree of WHO grades 3 and 4 non-hematological toxicities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Feminino , Gastroenteropatias/induzido quimicamente , Doenças Hematológicas/induzido quimicamente , Humanos , Hidroxiureia/administração & dosagem , Hidroxiureia/efeitos adversos , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Leucemia Mieloide de Fase Crônica/mortalidade , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/induzido quimicamente , Proteínas Recombinantes , Resultado do Tratamento
7.
Ann Oncol ; 13(7): 1017-28, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12176779

RESUMO

BACKGROUND: This investigation evaluates prognostic variables in patients with seminomatous and non-seminomatous extragonadal germ-cell tumors (EGCT) in order to identify relevant factors for long-term outcome following cisplatin-based chemotherapy. PATIENTS AND METHODS: Patients from six countries treated at 11 centers in Europe and the USA from 1975 to 1996 were evaluated retrospectively. Uni- and multivariate analyses of prognostic variables for survival and for response to chemotherapy were performed. RESULTS: Data were available for 635 EGCT patients, 104 with seminomatous and 524 with non-seminomatous EGCT (n = 7 not specified). For non-seminomatous EGCT the following independent adverse factors were identified: presence of either liver, lung or central nervous system metastases, primary mediastinal tumor or elevation of pretreatment beta-human gonadotropin; for extragonadal seminoma (only univariate) adverse factors were: presence of liver metastases, two or greater metastatic sites or International Germ Cell Cancer Collaborative Group (IGCCCG) grouping (intermediate versus good). Integration of these variables produced the following prognostic risk groupings: 'excellent prognosis', all seminomatous EGCT (89% 5-year survival rate); 'intermediate low', 'intermediate high' and 'poor', all non-seminomatous EGCT with a 69, 55 and 17% 5-year survival rate, respectively. The decreased survival among the different groups was due to a lower rate of favorable objective remissions and a higher rate of relapses. Classification and regression tree (CART) modeling confirmed histology and location of primary tumor as the major prognosticators. For the subgroup of patients with mediastinal non-seminoma, the 2-year survival rate ranged from 34 to 84%. Multivariate testing for the probability to respond to chemotherapy revealed non-seminomatous histology, primary mediastinal tumor site, and the presence of liver, lung or CNS metastases as independent adverse factors. CONCLUSIONS: In EGCT, prognostic variables for the outcome and for the response to chemotherapy could be identified, which in part differ from gonadal GCT. The proposed model might help to better understand the specific prognosis of EGCT and to tailor risk-adapted treatment strategies. In addition, CART analysis demonstrated the heterogenous prognosis of patients with mediastinal non-seminoma.


Assuntos
Neoplasias Abdominais/tratamento farmacológico , Neoplasias Abdominais/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores Tumorais/análise , Germinoma/tratamento farmacológico , Germinoma/patologia , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias do Mediastino/patologia , Neoplasias Abdominais/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Análise de Variância , Biópsia por Agulha , Gonadotropina Coriônica/análise , Intervalo Livre de Doença , Europa (Continente)/epidemiologia , Germinoma/mortalidade , Humanos , Neoplasias do Mediastino/mortalidade , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Probabilidade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologia , alfa-Fetoproteínas/análise
8.
Onkologie ; 25(3): 249-54, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12119459

RESUMO

BACKGROUND: Alternative and effective drug regimens in patients with metastatic breast cancer progressing after adriamycin- and taxoid-containing regimens are urgently needed. PATIENTS AND METHODS: In a phase II trial, 43 heavily pretreated patients with metastatic breast cancer were treated with both carboplatin 200 mg/m(2) i.v. and mitomycin C 10 mg/m(2) i.v. on day 1 every 4 weeks. In case of granulocytopenia or thrombocytopenia below grade 3 according to NCI-CTC, the carboplatin dosage was escalated to 300, 400, and 450 mg/m(2) in the next treatment cycle. RESULTS: During the first 3 cycles the dose intensity of carboplatin could be increased from a mean of 50 to 74 mg/m(2)/week. Beyond this value the carboplatin dose intensity decreased because of hematotoxicity. Based on an intention-to-treat analysis, 9 of 43 patients responded to therapy (21%; 95% CI = 10.04-36.04) including 2 complete and 7 partial responses. 15 patients had no change, 13 progressed, and 6 patients were considered nonevaluable. The median time to progression was 3 (range 0-12) months. NCI-CTC grade 3 or 4 granulocytopenia was observed in 14 patients, grade 3 or 4 thrombocytopenia occurred in 32, grade 3 infections in 3, grade 3 hemorrhage in 1, and grade 3 cardiac dysrhythmias in 1 of the patients. CONCLUSIONS: In anthracycline/ taxoid-pretreated patients, salvage treatment with a combination of carboplatin and mitomycin C seems to be effective and associated with foreseeable toxicity. Based on our results with an intraindividual dose escalation of carboplatin, a dosage of 300 mg/m(2) in combination with mitomycin C 10 mg/m(2) every 4 weeks seems to represent a recommendable starting dose for future studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Terapia de Salvação , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Terapia Combinada , Progressão da Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
9.
Br J Cancer ; 85(10): 1462-6, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11720429

RESUMO

The majority of lymphomas of the mucosa-associated lymphoid tissue (MALT)-type arise in the stomach, but extragastric locations are also frequently encountered. Due to previous results indicating that somatostatin receptor (SSTR)-expression distinguishes between gastric and extragastric MALT-type lymphoma, we have initiated a study to evaluate the role of SSTR-scintigraphy for staging and follow-up of patients with extragastric manifestations of MALT-type lymphoma. A total of 30 consecutive patients, including 24 with primary extragastric MALT-type lymphoma, 5 patients with dissemination to extragastric sites (including colon, lung, parotid, ocular adnexa and breast) following an initial gastric MALT-lymphoma and one patient with spread to stomach, lung and lymph nodes following parotid lymphoma were prospectively studied. All patients had histologically verified MALT-type lymphoma: 2 patients had lymphoma presenting in the lung, 9 in the ocular adnexa, 7 had lymphomas in the parotid, 2 patients had disease located in the breast, 3 patients had lymph-node relapse following MALT-type lymphoma of the parotid, the lacrimal gland and the thyroid, and 1 had primary MALT-lymphoma of the liver. All patients underwent SSTR-scintigraphy using (111)In-DTPA-D-Phe(1)-Octreotide ((111)In-OCT) before initiation of therapy, while 13 also had a second scan after treatment. The results of gamma camera imaging were compared to conventional staging. No positive scans could be obtained in patients with dissemination following gastric lymphoma, while all patients with primary extragastric lymphoma had positive scans at the site of histologically documented involvement before initiation of therapy. In addition, also the patient with secondary spread to stomach, lung and lymph nodes was positive in all documented lymphoma sites. In one patient, focal tracer uptake in projection to the maxillary sinus was documented, which was bioptically verified as inflammation. In the scans performed after therapy, focal tracer accumulation in the left orbit indicated persistence of disease following irradiation in one patient with otherwise negative work-up, which was verified by MRI and biopsy 6 months later. In another patient, a positive scan indicated disease relapse in the lacrimal gland 9 months before clinical verification by means of ultrasound. In one patient, a focus not present in the pretherapeutic scan was found in the ethmoidal sinus, corresponding to a hyperplastic polyp. Both SST-scan as well as CT indicated disease persistence in one case, while negative scans corresponding to complete remission as judged by conventional staging were obtained following therapy in the remaining patients, and absence of relapse has been confirmed for a median follow-up of 2 years. These results indicate that (111)In-OCT is an excellent tool for staging and non-invasive therapy-monitoring in extragastric MALT-type lymphomas. These data further confirm our initial finding that gastric MALT-type lymphomas do not express relevant amounts of respective SSTR, and that SSTR-scanning is able to distinguish between gastric vs extragastric origin of MALT-type lymphoma irrespective of the site of presentation.


Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Octreotida/análogos & derivados , Ácido Pentético/análogos & derivados , Receptores de Somatostatina/análise , Adulto , Idoso , Feminino , Seguimentos , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico por imagem , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos
10.
J Natl Cancer Inst ; 93(22): 1733-8, 2001 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-11717334

RESUMO

BACKGROUND: The frequency of subsequent testicular cancer (referred to as metachronous testicular cancer) in men who have had previous testicular cancer is relatively high. The rate of metachronous testicular cancer in men with extragonadal germ cell tumors (EGCTs), however, is largely unknown. We conducted a retrospective study of EGCT patients to determine the incidence, cumulative risk, and specific risk factors for metachronous testicular cancers. METHODS: A standardized questionnaire about patient characteristics, the extent of EGCT disease, any second malignancies, and treatments received was completed for 635 patients with EGCTs identified from the medical records of 11 cancer centers in Europe and the United States from 1975 through 1996. Comparisons with age group-specific data from the Saarland, Germany, population-based cancer registry were used to calculate the standardized incidence ratio (SIR). The Kaplan-Meier method was used to analyze survival data and cumulative risk. All statistical tests were two-sided. RESULTS: Sixteen EGCT patients (4.1%) developed metachronous testicular cancers, with a median time between diagnoses of 60 months (range, 14-102 months). The risk of developing metachronous testicular cancers was statistically significantly increased in patients with EGCTs (observed = 16; expected = 0.26; SIR = 62; 95% confidence interval [CI] = 36 to 99) and in subsets of EGCT patients with mediastinal location (SIR = 31; 95% CI = 8 to 59), retroperitoneal location (SIR = 100; 95% CI = 54 to 172), and nonseminomatous histology (SIR = 75; 95% CI = 43 to 123). The cumulative risk of developing a metachronous testicular cancer 10 years after a diagnosis of EGCT was 10.3% (95% CI = 4.9% to 15.6%) and was higher among patients with nonseminomatous EGCTs (14.3%; 95% CI = 6.7% to 21.9%) and retroperitoneal EGCTs (14.2%; 95% CI = 5.6% to 22.8%) than among patients with seminomatous EGCTs (1.4%; 95% CI = 0.0% to 4.2%) and mediastinal EGCTs (6.2%; 95% CI = 0.1% to 12.2%). CONCLUSIONS: Patients with EGCTs, particularly those with retroperitoneal or nonseminomatous tumors, but also those with primary mediastinal EGCTs, are at an increased risk of metachronous testicular cancer.


Assuntos
Neoplasias Embrionárias de Células Germinativas/complicações , Segunda Neoplasia Primária/epidemiologia , Neoplasias Testiculares/epidemiologia , Adolescente , Adulto , Idoso , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Segunda Neoplasia Primária/etiologia , Segunda Neoplasia Primária/mortalidade , Estudos Retrospectivos , Fatores de Risco , Neoplasias Testiculares/etiologia , Neoplasias Testiculares/mortalidade , Fatores de Tempo
11.
J Clin Oncol ; 19(17): 3740-4, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11533096

RESUMO

PURPOSE: To establish the predictive potential of 2-18fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) for detecting viable tumor tissue in residual postchemotherapy masses of seminoma patients. PATIENTS AND METHODS: In this prospective multicenter trial, results of FDG PET studies in seminoma patients with postchemotherapy masses > or = 1 cm were correlated with either the histology of the resected lesion or the clinical outcome on follow-up without resection. Negative PET scans of residual lesions that were devoid of viable tumor tissue on resection or disappeared, shrunk, or remained stable in size for at least 2 years were rated as true-negative (TN). Positive scans without histologic or clinical evidence of tumor tissue were classified as false-positive. In patients with histologically positive or progressive lesions, positive PET scans were defined as true-positive (TP) and negative scans, false-negative (FN). RESULTS: Thirty-seven PET scans of 33 patients were assessable at a median follow-up time of 23 months (range, 2 to 46 months). Histologic data were available from nine patients who had undergone resection. Twenty-eight patients were followed-up clinically and radiologically. Twenty-eight scans were TN, eight were TP, and one was FN. All 14 residual lesions more than 3 cm and 22 (96%) of the 23 < or = 3 cm were correctly predicted by FDG PET. The specificity (100%; 95% confidence interval [CI], 87.7% to 100%), sensitivity (89%; 95% CI, 51.7% to 99.7%), positive predictive value (100%), and the negative predictive value (97%) of FDG PET were superior to data obtained by assessing residual tumor size (< or = or > 3 cm). CONCLUSION: FDG PET is a clinically useful predictor of viable tumor in postchemotherapy residuals of pure seminoma, especially those greater than 3 cm.


Assuntos
Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos , Seminoma/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Seminoma/tratamento farmacológico , Sensibilidade e Especificidade , Neoplasias Testiculares/tratamento farmacológico
12.
J Biol Chem ; 276(40): 36909-16, 2001 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11470785

RESUMO

Several mutations of residues Glu(795) and Glu(820) present in M5 and M6 of the catalytic subunit of gastric H(+),K(+)-ATPase have resulted in a K(+)-independent, SCH 28080-sensitive ATPase activity, caused by a high spontaneous dephosphorylation rate. The mutants with this property also have a preference for the E(1) conformation. This paper investigates the question of whether these two phenomena are coupled. This possibility was studied by combining mutations in residue Glu(343), present in M4, with those in residues 795 and 820. When in combined mutants Glu and/or Gln residues were present at positions 343, 795, and 820, the residue at position 820 dominated the behavior: a Glu giving K(+)-activated ATPase activity and an E(2) preference and a Gln giving K(+)-independent ATPase activity and an E(1) preference. With an Asp at position 343, the enzyme could be phosphorylated, but the dephosphorylation was blocked, independent of the presence of either a Glu or a Gln at positions 795 and 820. However, in these mutants, the direction of the E(2) <--> E(1) equilibrium was still dominated by the 820 residue: a Glu giving E(2) and a Gln giving E(1). This indicates that the preference for the E(1) conformation of the E820Q mutation is independent of an active dephosphorylation process.


Assuntos
ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Potássio/metabolismo , Estômago/enzimologia , Animais , Células Cultivadas , Ácido Glutâmico/genética , ATPase Trocadora de Hidrogênio-Potássio/química , ATPase Trocadora de Hidrogênio-Potássio/genética , Insetos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutagênese Sítio-Dirigida , Fosforilação/efeitos dos fármacos , Conformação Proteica , Ratos , Vanadatos/farmacologia
13.
Biochim Biophys Acta ; 1538(2-3): 329-38, 2001 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11336804

RESUMO

Phospholipase D (PLD) is distributed widely in mammalian tissues where it is believed to play an important role in the regulation of cell functions and cell fate by a variety of extracellular signals. In this study, we used primary cultures of rabbit connecting tubule (CNT) and cortical collecting duct (CCD) cells, grown to confluence on a permeable support, to investigate the possible involvement of PLD in the mechanism of action of hormones that regulate Ca(2+) reabsorption. RT-PCR revealed the presence of transcripts of PLD1b and PLD2, but not PLD1a, in these cultures. Moreover, the expression of substantial amounts of PLD1 protein was demonstrated by Western blotting. To measure PLD activity, cells were labelled with [(3)H]myristic acid after which the PLD-catalysed formation of radiolabelled phosphatidylethanol ([(3)H]PtdEth) was measured in the presence of 1% (v/v) ethanol. Deamino-Cys,D-Arg(8)-vasopressin (dDAVP) and N(6)-cyclopentyladenosine (CPA), two potent stimulators of Ca(2+) transport across these monolayers, stimulated PLD activity as was indicated by a marked increase in [(3)H]PtdEth. Similarly, ATP, a potent inhibitor of dDAVP- and CPA-stimulated Ca(2+) transport, increased the formation of [(3)H]PtdEth. PLD activity was furthermore increased by 8Br-cAMP and following acute (30 min) stimulation of protein kinase C (PKC) with a phorbol ester (PMA). Chronic PMA treatment (120 h) to downregulate phorbol ester-sensitive PKC isoforms did not affect PLD activation by dDAVP, CPA and 8Br-cAMP, while markedly decreasing the effect of ATP and abolishing the effect of PMA. The PKC inhibitor chelerythrine significantly reduced PLD activation by dDAVP, CPA and 8Br-cAMP, without changing the effect of ATP. The inhibitor only partially reduced the effect of PMA. This study shows that Ca(2+) transporting cells of CNT and CCD contain a regulated PLD activity. The physiological relevance of this activity, which is not involved in Ca(2+) reabsorption, remains to be established.


Assuntos
Cálcio/metabolismo , Hormônios/farmacologia , Túbulos Renais Coletores/enzimologia , Fosfolipase D/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Trifosfato de Adenosina/farmacologia , Animais , Transporte Biológico , Cátions Bivalentes , Células Cultivadas , Desamino Arginina Vasopressina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Glicerofosfolipídeos/análise , Isoenzimas/metabolismo , Modelos Químicos , Coelhos , Acetato de Tetradecanoilforbol/farmacologia , Trítio
14.
J Clin Oncol ; 19(10): 2647-57, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11352956

RESUMO

PURPOSE: To assess the value of postsurgery chemotherapy in patients with disseminated nonseminomatous germ-cell tumors (NSGCTs) and viable residual disease after first-line cisplatin-based chemotherapy. PATIENTS AND METHODS: The outcome of 238 patients was reviewed. Tumor markers had normalized in all patients before resection. A multivariate analysis of survival was performed on 146 patients. RESULTS: The 5-year progression-free survival (PFS) rate was 64% and the 5-year overall survival (OS) rate was 73%. Three factors were independently associated with both PFS and OS: complete resection (P <.001), < 10% of viable malignant cells (P =.001), and a good International Germ Cell Consensus Classification (IGCCC) group (P =.01). Patients were assigned to one of three risk groups: those with no risk factors (favorable group), those with one risk factor (intermediate group), and those with two or three risk factors (poor-risk group). The 5-year OS rate was 100%, 83%, and 51%, respectively (P <.001). The 5-year PFS rate was 69% (95% confidence interval [CI], 62% to 76%) and 52% (95% CI, 40% to 64%) in postoperative chemotherapy recipients and nonrecipients, respectively (P <.001). No significant difference was detected in 5-year OS rates. After adjustment on the three prognostic factors, postoperative chemotherapy was associated with a significantly better PFS (P <.001) but not with better OS. Patients in the favorable risk group had a 100% 5-year OS, with or without postoperative chemotherapy. Postoperative chemotherapy appeared beneficial in both PFS (P <.001) and OS (P =.02) in the intermediate-risk group but was not statistically beneficial in the poor-risk group. CONCLUSION: A complete resection may be more critical than recourse to postoperative chemotherapy in the setting of postchemotherapy viable malignant NSGCT. Immediate postoperative chemotherapy or surveillance alone with chemotherapy at relapse may be reasonable options depending on the completeness of resection, IGCCC group, and percent of viable cells. Validation is necessary.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Germinoma/tratamento farmacológico , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias Retroperitoneais/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adulto , Análise de Variância , Terapia Combinada , Intervalo Livre de Doença , Germinoma/mortalidade , Germinoma/patologia , Germinoma/cirurgia , Humanos , Masculino , Neoplasias do Mediastino/mortalidade , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/cirurgia , Estudos Multicêntricos como Assunto , Prognóstico , Neoplasias Retroperitoneais/mortalidade , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/cirurgia , Estudos Retrospectivos , Neoplasias Testiculares/mortalidade , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia
15.
Biochemistry ; 40(21): 6527-33, 2001 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-11371216

RESUMO

Six double mutants of Glu(795) and Glu(820) present in transmembrane domains 5 and 6 of the alpha-subunit of rat gastric H(+),K(+)-ATPase were generated and expressed with the baculovirus expression system. Five of the six mutants exhibited an SCH 28080-sensitive ATPase activity in the absence of K(+). The activity levels decreased in the following order: E795Q/E820A > E795Q/E820Q > E795Q/E820D congruent with E795A/E820A > E795L/E820Q. The E795L/E820D mutant possessed no constitutive activity. The relative low ATPase activity of the E795L/E820Q mutant is due to its low phosphorylation rate so that the dephosphorylation step was no longer rate-limiting. The constitutively active mutants showed a much lower vanadate sensitivity than the wild-type enzyme and K(+)-sensitive mutants, indicating that these mutants have a preference for the E(1) conformation. In contrast to the constitutively active single mutants generated previously, the double mutants exhibited a high spontaneous dephosphorylation rate at 0 degrees C compared to that of the wild-type enzyme. In addition, the H(+),K(+)-ATPase inhibitor SCH 28080 increased the steady-state phosphorylation level of the constitutively active mutants, due to the formation of a stable complex with the E(2)-P form. These studies further substantiate the idea that the empty ion binding pockets of some mutants apparently mimic the K(+)-filled binding pocket of the native enzyme.


Assuntos
Substituição de Aminoácidos/genética , Ácido Glutâmico/genética , ATPase Trocadora de Hidrogênio-Potássio/genética , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Mutagênese Sítio-Dirigida , Potássio/metabolismo , Estômago/enzimologia , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Animais , Baculoviridae/genética , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Inibidores Enzimáticos/farmacologia , Hidroxilamina/farmacologia , Imidazóis/farmacologia , Fosforilação/efeitos dos fármacos , Inibidores da Bomba de Prótons , Ratos , Spodoptera/enzimologia , Spodoptera/genética
16.
Cancer ; 91(7): 1394-401, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11283942

RESUMO

BACKGROUND: The objectives of this study were to evaluate the long term outcome of patients with extragonadal seminomatous germ cell tumors (GCT) so that prognostic variables for disease recurrence and patient survival could be identified and to access the efficacy of different treatment modalities. METHODS: Six hundred thirty-five patients with extragonadal GCT who were treated consecutively at 11 centers in the United States and Europe during the cisplatin-based chemotherapy era between 1975 and 1996 were evaluated retrospectively. RESULTS: Fifty-two patients with primary retroperitoneal GCT (50%) and 51 patients with primary mediastinal GCT (49%) of pure seminomatous histology were identified (n = 1 patient with a primary cervical lymph node) representing 16.4% of 635 patients with extragonadal GCT who were included in the data base. The median age was 37 years (range, 18-70 years). Treatment consisted of platin-based chemotherapy in 77 patients (74%), radiotherapy in 9 patients (9%), and combined modality in 18 patients (17%). Ninety-two percent of patients (95% confidence interval, 87-97%) achieved a favorable response to primary therapy. After a median follow-up of 61 months (range, 1-211 months), 18 patients (17%) have had recurrent disease: 14% of those who received chemotherapy and 67% of those who received radiation therapy. The 5-year progression free survival rate favored the chemotherapy group, with 87% compared with 33% for irradiated patients (P = 0.006), whereas the overall survival rates were equal (90% vs. 67%; P = 0.13). No differences in overall survival or progression free survival were observed among patients with primary retroperitoneal and mediastinal seminoma. Prognostic factors that were identified to influence survival negatively were liver metastases (P = 0.01) and two or more metastatic sites (P = 0.04). CONCLUSIONS: In patients with extragonadal seminoma, a survival rate of > 90% at 5 years is achieved with adequate cisplatin-based chemotherapy. Compared with patients with nonseminomatous extragonadal GCT, no difference in long term survival exists between patients with primary retroperitoneal or mediastinal seminoma location. Primary radiotherapy seems to be associated with a significantly higher rate of disease recurrence, although most patients will be salvaged by subsequent chemotherapy.


Assuntos
Neoplasias do Mediastino/terapia , Neoplasias Retroperitoneais/terapia , Seminoma/terapia , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Cisplatino/uso terapêutico , Terapia Combinada , Seguimentos , Humanos , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/mortalidade , Neoplasias do Mediastino/patologia , Pessoa de Meia-Idade , Prognóstico , Neoplasias Retroperitoneais/diagnóstico , Neoplasias Retroperitoneais/mortalidade , Neoplasias Retroperitoneais/patologia , Seminoma/diagnóstico , Seminoma/mortalidade , Seminoma/secundário , Taxa de Sobrevida , Resultado do Tratamento
17.
J Pediatr Gastroenterol Nutr ; 32(2): 168-70, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11321387

RESUMO

BACKGROUND: Patients who undergo liver transplantation require multifaceted general care, and vaccination has a fundamental role before and after transplantation. The purpose of this study was to provide a prospective evaluation of the immunogenicity of the recombinant vaccine (RV) against Hepatitis B in pediatric patients with liver transplants (TxH) who for different reasons did not receive a pretransplantation vaccine. METHODS: From June 1996 to December 1999, 47 pediatric patients with liver transplants were vaccinated with RV. Patients older than 1 year of age, in stable condition, and 6 months post-transplantation were included. The vaccination scheme was 0-1 and 6 months, intramuscular 10 microg in less than 30 kg body weight, and 20 microg in more than 30 kg body weight. The nonresponder patients were vaccinated with a booster dose and a double dose 1 to 6 months after the last dose. Responders to titer HBs Ab enzyme immunoassay (EIA) <10 UI/ml were defined as nonresponders, to titer between 10-100 UI/ml as responders, and to higher titer of 100 UI/ml as high responders. RESULTS: The following data were obtained from the 47 patients: mean +/- standard deviation (SD) age at vaccination was 10.76 +/- 5.96 years old and the mean +/- SD post-transplant time at the beginning of vaccination was 3.56 +/- 2.19 years. Thirty-three of 47 patients (70%) responded to doses according to body weight, and 14 (30%) did not respond, necessitating a booster dose after which 7 responded (50%). The global seroconversion was 85%. There was not a significant responder cyclosporine concentration dosage (154 vs. 150 ng/ml) difference between responders and nonresponders. Sixty-six percent (8 of 12) of patients receiving a triple immunosuppressive scheme (cyclosporine, steroids, and Azathioprine) had a positive response, while 84% (16 of 19) receiving a double scheme (cyclosporine and steroids) and 100% (16 of 16) receiving monotherapy with cyclosporine had a positive response. By comparing a triple scheme with monotherapy, the Fisher exact test found a P < 0.01. Incidence of adverse effects (local pain) was 2.63%. CONCLUSION: Immunization with RV was well-tolerated with acceptable seroconversion and safety in recipients after liver transplantation, particularly in those undergoing cyclosporine monotherapy. The population studied showed better results than did other populations of immunosuppressed patients.


Assuntos
Anticorpos Anti-Hepatite B/biossíntese , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Transplante de Fígado , Vacinas Sintéticas/imunologia , Criança , Ciclosporina , Esquema de Medicação , Feminino , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunização Secundária , Técnicas Imunoenzimáticas , Imunossupressores , Injeções Intramusculares , Transplante de Fígado/imunologia , Masculino , Estudos Prospectivos , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem
18.
J Biol Chem ; 276(15): 11705-11, 2001 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-11278751

RESUMO

In this study we reveal regions of Na(+),K(+)-ATPase and H(+),K(+)-ATPase that are involved in cation selectivity. A chimeric enzyme in which transmembrane hairpin M5-M6 of H(+),K(+)-ATPase was replaced by that of Na(+),K(+)-ATPase was phosphorylated in the absence of Na(+) and showed no K(+)-dependent reactions. Next, the part originating from Na(+),K(+)-ATPase was gradually increased in the N-terminal direction. We demonstrate that chimera HN16, containing the transmembrane segments one to six and intermediate loops of Na(+),K(+)-ATPase, harbors the amino acids responsible for Na(+) specificity. Compared with Na(+),K(+)-ATPase, this chimera displayed a similar apparent Na(+) affinity, a lower apparent K(+) affinity, a higher apparent ATP affinity, and a lower apparent vanadate affinity in the ATPase reaction. This indicates that the E(2)K form of this chimera is less stable than that of Na(+),K(+)-ATPase, suggesting that it, like H(+),K(+)-ATPase, de-occludes K(+) ions very rapidly. Comparison of the structures of these chimeras with those of the parent enzymes suggests that the C-terminal 187 amino acids and the beta-subunit are involved in K(+) occlusion. Accordingly, chimera HN16 is not only a chimeric enzyme in structure, but also in function. On one hand it possesses the Na(+)-stimulated ATPase reaction of Na(+),K(+)-ATPase, while on the other hand it has the K(+) occlusion properties of H(+),K(+)-ATPase.


Assuntos
ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , ATPase Trocadora de Hidrogênio-Potássio/química , Fosforilação , Potássio/metabolismo , Ratos , Proteínas Recombinantes de Fusão/química , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/química
19.
J Clin Oncol ; 19(6): 1641-8, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11250992

RESUMO

PURPOSE: Relapsed extragonadal germ cell tumors patients (EGGCT) are treated with identical salvage chemotherapy regimens, as are patients with metastatic testicular cancer. This investigation evaluates the results of second-line chemotherapy in nonseminomatous EGGCT and tries to identify prognostic factors for survival. PATIENTS AND METHODS: We conducted a retrospective review of 142 patients treated at eleven European and American centers between 1975 and 1996. All had received cisplatin-containing regimens as induction treatment. RESULTS: Twenty-seven of 142 patients (19%) were long-term disease-free, 11% with primary mediastinal and 30% of patients with primary retroperitoneal disease. Median follow-up since start of salvage treatment was 11 months (range, 1 to 157) for all patients and 45 months (range, 6 to 157) for surviving patients. Forty-eight patients (34%) received high dose chemotherapy with autologous bone marrow transplant at relapse, and 10 of these patients (21%) are continuously disease-free. Primary mediastinal location (P =.003), sensitivity to cisplatin (P =.003), elevated beta-HCG at relapse (P: =.04), and normal LDH at diagnosis (P =.01) were shown to be significant negative prognostic factors for overall survival in univariate; mediastinal location [relative risk ratios (HR) = 1.9; 95% confidence intervals (CI), 1.2 to 3.0] and sensitivity to cisplatin [HR = 2.4; 95% CI, 1.1 to 5.2] were significant negative prognostic factors in multivariate analysis. CONCLUSION: Although current salvage strategies will cure between 20% and 50% of recurrent metastatic testicular cancer, relapsed nonseminomatous EGGCT patients appear to have an inferior survival rate, in particular in case of primary mediastinal location. Mediastinal primary tumor and inadequate response to cisplatin-based induction chemotherapy have been identified as independent negative prognostic factors, both associated with an approximately two-fold higher risk for failure of salvage treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Retroperitoneais/tratamento farmacológico , Adolescente , Adulto , Idoso , Cisplatino/administração & dosagem , Humanos , Masculino , Neoplasias do Mediastino/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia , Neoplasias Embrionárias de Células Germinativas/patologia , Prognóstico , Neoplasias Retroperitoneais/patologia , Estudos Retrospectivos , Fatores de Risco , Terapia de Salvação , Análise de Sobrevida , Resultado do Tratamento
20.
Gastroenterology ; 120(2): 377-86, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159878

RESUMO

BACKGROUND & AIMS: The proton pump H(+),K(+)-adenosine triphosphatase (H(+),K(+)-ATPase) of parietal cells is the major humoral autoantigen in both human and experimental autoimmune gastritis (AIG) characterized by an inflammatory infiltrate in the gastric mucosa and loss of parietal cells. The aim of this study was to detect H(+),K(+)-ATPase-specific T cells in the gastric mucosa of patients with AIG and to define their functional properties. METHODS: In vivo-activated T cells from the infiltrates of the gastric mucosa of 5 patients with AIG were isolated and cloned. The ability of gastric T-cell clones to proliferate and to produce cytokines in response to H(+),K(+)-ATPase, as well as their expression of B-cell help, perforin-mediated cytotoxicity, and Fas-Fas ligand-mediated apoptosis in target cells, were assessed. RESULTS: A proportion (25%) of the CD4(+) clones from the gastric corpus of AIG patients proliferated in response to porcine H(+),K(+)-ATPase. Most of these clones (88%) showed a Th1 profile, whereas a few secreted both Th1 and Th2 cytokines. Virtually all of the H(+),K(+)-ATPase-specific clones produced tumor necrosis factor alpha and provided substantial help for B-cell immunoglobulin production, and most of them expressed perforin-mediated cytotoxicity against antigen-presenting cells and induced Fas-Fas ligand-mediated apoptosis in target cells. CONCLUSIONS: Activation of proton pump-specific Th1 cytotoxic/proapoptotic T cells in the gastric mucosa can represent an effector mechanism for the target cell destruction in AIG.


Assuntos
Doenças Autoimunes/imunologia , Gastrite/imunologia , ATPase Trocadora de Hidrogênio-Potássio/imunologia , Linfócitos T Citotóxicos/imunologia , Células Th1/imunologia , Adulto , Autoantígenos/imunologia , Doenças Autoimunes/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biópsia , Morte Celular/imunologia , Células Clonais , Epitopos , Proteína Ligante Fas , Feminino , Mucosa Gástrica/imunologia , Gastrite/patologia , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Humanos , Imunoglobulina G/biossíntese , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Perforina , Proteínas Citotóxicas Formadoras de Poros , Células Th1/enzimologia
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