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1.
Artigo em Inglês | MEDLINE | ID: mdl-37813239

RESUMO

INTRODUCTION: Amino acid PET is a tool recommended by the main neuroimaging societies in the differential diagnosis between radionecrosis (RNC) and umour recurrence (TR) in brain tumours, but its use in our country is still limited. The aim of this work is to present our experience with 6-[18F]FDOPA PET/CT (FDOPA) in brain tumours (primary and M1), comparing these results with other published results. MATERIAL AND METHODS: Retrospective study of 62 patients with suspected tumour recurrence (TR): 42 brain metastases (M1) and 20 primary, who underwent FDOPA. Images were analysed visually and semi-quantitatively, obtaining SUVmax and SUVmaxlesion/SUVmaxstriatum (L/S) and SUVmaxlesion/SUVmaxcortex (L/C) ratios. The diagnostic validity of PET was analysed and the best performing cut-off points were calculated. PET results were compared with clinical-radiological follow-up and/or histopathology. RESULTS: TR was identified in 49% of M1 and 76% of brain primaries. The best performing FDOPA interpretation was visual and semi-quantitative, with a sensitivity and specificity in primaries of 94% and 80% and in M1s of 96% and 72% respectively. The cut-off points with the best diagnostic performance were L/C1.44 in M1 and L/C1.55 in primaries. There are discrepant results with other published results. CONCLUSION: FDOPA PET/CT is a useful tool in the differential diagnosis between recurrence and RNC in brain tumours. It is needed a standardization to contribute to homogenise FDOPA results a inter-centre level.


Assuntos
Neoplasias Encefálicas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons/métodos , Di-Hidroxifenilalanina , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia
2.
Clin Transl Oncol ; 20(12): 1529-1537, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29737461

RESUMO

PURPOSE: We retrospectively examined the potential effect on overall survival (OS) of delaying radiotherapy to administer neoadjuvant therapy in unresected glioblastoma patients. PATIENTS AND METHODS: We compared OS in 119 patients receiving neoadjuvant therapy followed by standard treatment (NA group) and 96 patients receiving standard treatment without neoadjuvant therapy (NoNA group). The MaxStat package of R identified the optimal cut-off point for waiting time to radiotherapy. RESULTS: OS was similar in the NA and NoNA groups. Median waiting time to radiotherapy after surgery was 13 weeks for the NA group and 4.2 weeks for the NoNA group. The longest OS was attained by patients who started radiotherapy after 12 weeks and the shortest by patients who started radiotherapy within 4 weeks (12.3 vs 6.6 months) (P = 0.05). OS was 6.6 months for patients who started radiotherapy before the optimal cutoff of 6.43 weeks and 19.1 months for those who started after this time (P = 0.005). Patients who completed radiotherapy had longer OS than those who did not, in all 215 patients and in the NA and NoNA groups (P = 0.000). In several multivariate analyses, completing radiotherapy was a universally favorable prognostic factor, while neoadjuvant therapy was never identified as a negative prognostic factor. CONCLUSION: In our series of unresected patients receiving neoadjuvant treatment, in spite of the delay in starting radiotherapy, OS was not inferior to that of a similar group of patients with no delay in starting radiotherapy.


Assuntos
Neoplasias Encefálicas/terapia , Quimioterapia Adjuvante/métodos , Glioblastoma/terapia , Radioterapia/métodos , Tempo para o Tratamento , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/mortalidade , Quimiorradioterapia/métodos , Feminino , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Resultado do Tratamento
3.
Clin Transl Oncol ; 20(1): 3-15, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29124520

RESUMO

Diffuse infiltrating low-grade gliomas include oligodendrogliomas and astrocytomas, and account for about 5% of all primary brain tumors. Treatment strategies for these low-grade gliomas in adults have recently changed. The 2016 World Health Organization (WHO) classification has updated the definition of these tumors to include their molecular characterization, including the presence of isocitrate dehydrogenase (IDH) mutation and 1p/19p codeletion. In this new classification, the histologic subtype of grade II-mixed oligoastrocytoma has also been eliminated. The precise optimal management of patients with low-grade glioma after resection remains to be determined. The risk-benefit ratio of adjuvant treatment must be weighed for each individual.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Glioma/diagnóstico , Glioma/terapia , Humanos
4.
Clin Transl Oncol ; 20(1): 108-109, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29209952

RESUMO

The original version of this article unfortunately contained a mistake. Figure 3 was incorrect.

5.
Clin Transl Oncol ; 17(9): 743-50, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26033428

RESUMO

PURPOSE: The aim of this prospective and multicentric phase II study was to evaluate the efficacy and safety of temozolomide (TMZ) and bevacizumab (BV) in patients (pts) with recurrent glioblastoma (GB), previously treated with chemoradiotherapy and at least three cycles of adjuvant TMZ. PATIENTS AND METHODS: Patients with GB at first relapse received BV 10 mg/kg day every 2 weeks and TMZ 150 mg/m(2) days 1-7 and 15-21, every 28 days. Patients underwent brain magnetic resonance imaging every 8 weeks. RESULTS: Thirty-two evaluable pts were recruited in 8 sites. Fourteen pts (44%) had gross total resection. O(6)-methylguanine-DNA methyltransferase (MGMT) promoter was methylated in 12 pts, unmethylated in 6 pts, and missing in 14 pts. The estimated 6-month progression free survival (PFS) rate was 21.9% (95% CI 9.3-40.0%). The median PFS and overall survival (OS) were 4.2 months (95% CI 3.6-5.4 months) and 7.3 months (95% CI 5.8-8.8 months), respectively. No significant association with MGMT status was found in terms of OS or PFS. Six of 32 pts (19%; 95% CI 7.2-36.4) were long-term survivors, with a median PFS and OS (50% events) of 9.5 months (95% CI 7.9-23.6) and 15.4 (95% CI 8.9-NA), respectively: no differences in baseline characteristics were identified in comparison with total population. No unexpected toxicities or treatment-related deaths were observed. CONCLUSIONS: This regimen showed to be feasible and well tolerated in pts with recurrent GB pretreated with TMZ. Further investigation is warranted to identify subpopulations that are more likely to benefit from addition of BV to GB therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Doenças Hematológicas , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Bevacizumab/administração & dosagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Estudos de Viabilidade , Feminino , Seguimentos , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Temozolomida
6.
Br J Cancer ; 108(12): 2565-72, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23722472

RESUMO

BACKGROUND: Owing to the limited validity of clinical data on the treatment of prostate cancer (PCa) and bone metastases, biochemical markers are a promising tool for predicting survival, disease progression and skeletal-related events (SREs) in these patients. The aim of this study was to evaluate the predictive capacity of biochemical markers of bone turnover for mortality risk, disease progression and SREs in patients with PCa and bone metastases undergoing treatment with zoledronic acid (ZA). METHODS: This was an observational, prospective and multicenter study in which ninety-eight patients were included. Patients were treated with ZA (4 mg every 4 weeks for 18 months). Data were collected at baseline and 3, 6, 9, 12, 15 and 18 months after the beginning of treatment. Serum levels of bone alkaline phosphtase (BALP), aminoterminal propeptide of procollagen type I (P1NP) and beta-isomer of carboxiterminal telopeptide of collagen I (ß-CTX) were analysed at all points in the study. Data on disease progression, SREs development and survival were recorded. RESULTS: Cox regression models with clinical data and bone markers showed that the levels of the three markers studied were predictive of survival time, with ß-CTX being especially powerful, in which a lack of normalisation in visit 1 (3 months after the beginning of treatment) showed a 6.3-times more risk for death than in normalised patients. Levels of these markers were also predictive for SREs, although in this case BALP and P1NP proved to be better predictors. We did not find any relationship between bone markers and disease progression. CONCLUSION: In patients with PCa and bone metastases treated with ZA, ß-CTX and P1NP can be considered suitable predictors for mortality risk, while BALP and P1NP are appropriate for SREs. The levels of these biomarkers 3 months after the beginning of treatment are especially important.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Remodelação Óssea , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/metabolismo , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/mortalidade , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Progressão da Doença , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Fatores de Risco , Análise de Sobrevida , Ácido Zoledrônico
7.
Clin Transl Oncol ; 15(11): 897-902, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23463593

RESUMO

PURPOSE: There is a need for biomarkers that may help in selecting the most effective anticancer treatments for each patient. We have investigated the prognostic value of a set of angiogenesis, inflammation and coagulation markers in patients treated for advanced non-small cell lung cancer. PATIENTS AND METHODS: Peripheral blood samples were obtained from 60 patients before first line platinum-based chemotherapy ± bevacizumab, and after the third cycle of treatment. Blood samples from 60 healthy volunteers were also obtained as controls. Angiogenesis, inflammation and coagulation markers vascular endothelial growth factor (VEGF), their soluble receptors 1 (VEGFR1) and 2 (VEGFR2), thrombospondin-1 (TSP-1), interleukin-6 (IL6), sialic acid (SA) and tissue factor (TF) were quantified by ELISA. RESULTS: Except for TSP-1, pre- and post-treatment levels of all markers were higher in patients than in controls (p < 0.05). There was a positive and significant correlation between VEGF and VEGFR2 before treatment. VEGF also correlated with inflammatory markers IL-6 and SA. Moreover, there was a positive and significant correlation between levels of VEGFR1 and TF. Decreased levels of TSP-1 and increased levels of VEGF were associated with shorter survival. Bevacizumab significantly modified angiogenesis parameters and caused a decrease of VEGF and an increase of TSP-1. CONCLUSION: Angiogenesis, inflammation and coagulation markers were increased in NSCLC patients. Increased levels of VEGF and low levels of TSP-1 correlated with a poor prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/sangue , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Neoplasias Pulmonares/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adenocarcinoma/sangue , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Carcinoma de Células Grandes/sangue , Carcinoma de Células Grandes/tratamento farmacológico , Carcinoma de Células Grandes/mortalidade , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Cisplatino/administração & dosagem , Docetaxel , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Taxoides/administração & dosagem
8.
J Clin Neurosci ; 17(1): 50-3, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19959364

RESUMO

In a consecutive series of 26 previously operated patients diagnosed with cerebral glioma, magnetic resonance spectroscopy (MRS), 2-((18)F) fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET), and perfusion MRI (MRP), were performed at follow-up to distinguish recurrence from radiation necrosis, and to identify tumour upgrading. Discrepancy between techniques was observed in 9 cases. The positive predictive value (PPV) and the negative predictive value (NPV) of each technique to detect the presence of high grade glioma was: MRI, PPV=50%; MRS, PPV=91.6%, NPV=100%; FDG-PET, PPV=75%, NPV=61.1%; MRP, PPV=100%, NPV=100%. In the selected group of nine cases studied to differentiate viable tumour from radiation necrosis, MRS and MRP reached a PPV and a NPV of 100%, whereas for FDG-PET, PPV and NPV were 66.6% and 60%, respectively. To distinguish between viable high-grade glioma and radiation necrosis, gadolinium-enhanced MRI gives a high false-positive rate, while MRS and MRP are superior to FDG-PET in discriminating tumour recurrence, grade increase and radiation necrosis.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Angiografia por Ressonância Magnética/estatística & dados numéricos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Recidiva Local de Neoplasia/patologia , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Adolescente , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/fisiopatologia , Diagnóstico Diferencial , Progressão da Doença , Reações Falso-Positivas , Feminino , Fluordesoxiglucose F18 , Gadolínio , Glioma/diagnóstico por imagem , Glioma/fisiopatologia , Humanos , Angiografia por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/fisiopatologia , Tomografia por Emissão de Pósitrons/métodos , Valor Preditivo dos Testes , Radioterapia/efeitos adversos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
9.
J Neurooncol ; 96(3): 417-22, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19669096

RESUMO

This multicenter phase II study conducted by the Spanish Neuro-Oncology Group evaluated the activity of an extended, dose-dense temozolomide regimen in patients with temozolomide-refractory malignant glioma. Adult patients (at least 18 years of age) with WHO grade III or IV glioma and a Karnofsky Performance Status of 60 or higher were treated with temozolomide (85 mg/m(2)/day) for 21 consecutive days every 28-day cycle until disease progression or unacceptable toxicity. All patients had developed progressive disease either during or less than 3 months after completing previous temozolomide treatment. Forty-seven patients were treated with a median of 2 (range, 1-13) cycles of temozolomide. Before study entry, patients had received a median of 6 cycles of temozolomide: 39 (83%) as part of initial therapy and 23 (49%) as second-line therapy. Three patients (6.4%) had a partial response with durations of 8.0, 3.5, and 3.2 months; 15 patients (31.9%) had stable disease with a median duration of 2.1 months, including 2 patients with stable disease (SD) for greater than 6 months (14 and 16 months). Median time to progression was 2 months, and median overall survival from study entry was 5.1 months. The 6-month progression-free survival rate was 16.7%. The most common hematologic toxicities were lymphopenia, thrombocytopenia, and leukopenia. Lymphopenia occurred in 83% of patients and was grade 3 in 28%, but no opportunistic infections occurred. In conclusion, this extended dose-dense schedule of temozolomide appears to have modest activity in patients refractory to previous treatment with temozolomide and is associated with manageable toxicity.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Dacarbazina/uso terapêutico , Esquema de Medicação , Sistemas de Liberação de Medicamentos , Feminino , Glioma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Temozolomida , Resultado do Tratamento , Adulto Jovem
11.
Ann Oncol ; 8(6): 547-53, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9261523

RESUMO

AIMS: a) To identify which pretreatment clinical or blood parameters were predictive of patients survival in small-cell lung cancer (SCLC) in a retrospective analysis. b) To validate three known prognostic indices: Royal Marsden Model (index 1), London Group (index 2) and Manchester Score (index 3). PATIENTS AND METHODS: From 1981 to 1993, 341 SCLC patients were treated with chemotherapy with or without surgery or radiotherapy. Univariate and multiple regression analyses of survival were performed and the feasibility of these models was explored, index 1: Karnofsky index, albumin, sodium and alkaline phosphatase; index 2: ECOG performance status (PS), albumin and alanine transaminase; and index 3; lactate dehydrogenase (LDH), disease extent, sodium, Karnofsky index, alkaline phosphatase and bicarbonate. RESULTS: Significant prognostic factors for survival after univariate and multiple regression analysis were: disease extent, PS, creatine kinase, neutrophilia, LDH, hypoalbuminemia, hyperglycemia and bicarbonate. A new prognostic index was performed that included LDH, hypoalbuminemia, neutrophilia, disease extent and PS. It defined three prognostic groups (PG). Median survival and two-year survival for these PG were 12.3, 8 and 3.4 months and 16.5%, 2.3% and 0%, respectively. The following PG were identified after application of the three models proposed: Index 1 identified two PG with 0% and 16.6% two-year survival (P < 0.001); index 2 detected three PG with 0%, 5% and 15.7% two-year survival (P < 0.001) and index 3 detected three PG with 0%, 2.5% and 16.2% two-year survivals, respectively (P < 0.001). CONCLUSION: A new prognostic index is proposed allowing identification of three different PG. The feasibility of three known prognostic models was validated and demonstrated. Variables other than disease extent or PS (albumin or LDH) should be taken into account in designing future clinical trials.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Pequenas/sangue , Carcinoma de Células Pequenas/diagnóstico , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Idoso , Análise de Variância , Carcinoma de Células Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
12.
Eur Urol ; 28(1): 19-24, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8521889

RESUMO

The records of 23 patients (22 male and 1 female, median age 28 years) with extragonadal germ cell tumors (EGCT) treated between 1974 and 1993 were reviewed retrospectively to investigate long-term survival and prognostic factors. Treatment consisted of cisplatin-based chemotherapy plus local irradiation or surgery. There were 7 seminomas, 5 poorly differentiated carcinomas (PDC) with elevated biomarkers, and 11 nonseminomatous germ cell tumors (NSGCT). The primary sites were retroperitoneum (10 cases), mediastinum (5 cases), pineal gland (4 cases) and other (4 cases). Two partial and 14 complete responses (69.6% overall) were achieved with primary therapy. After a median follow-up of 63 months, 10 (43.5%) patients live disease-free and 5-year survival is 55%. Seminomas showed an excellent outcome. Retroperitoneal NSGCT behaved like testicular neoplasms. Between nonseminoma patients, PDC histology and mediastinal primary were associated with the worst prognoses. EGCT patients should be treated and reported separately according to histology and primary site.


Assuntos
Neoplasias Embrionárias de Células Germinativas/mortalidade , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Carcinoma/mortalidade , Carcinoma/patologia , Carcinoma/terapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/secundário , Masculino , Neoplasias do Mediastino/mortalidade , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/terapia , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Glândula Pineal , Prognóstico , Neoplasias Retroperitoneais/mortalidade , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/terapia , Estudos Retrospectivos , Seminoma/mortalidade , Seminoma/patologia , Seminoma/terapia , Sobreviventes , Resultado do Tratamento
13.
Clin Chim Acta ; 162(3): 277-89, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3568404

RESUMO

Some binding assays have been suggested to measure serum testosterone--estradiol-binding globulin (TeBG) concentration. They have led to discrepant results. This study brought to surface the lack of these methods and the interest of a method using an accurate analysis of the binding isotherm. These observations led us to propose an absolute reference method especially suitable for the radioimmunological assays standardization. Our method used Con A Sepharose as a solid phase and DHT as a radioligand. We succeeded in solving the difficulties related to binding methods by evaluating the non-specific binding of the ligand and ligand--albumin binding. A careful analysis of experimental data, by setting equations specific to this DHT-TeBG system permitted the systematic errors to be corrected and allowed a precise determination of the serum TeBG concentration (27.3 +/- 6.0 nmol/l for 30 healthy men; 40 +/- 13 nmol/l for 15 healthy women). Moreover, the affinity constant of the ligand for the protein was accurately evaluated KDHT = (0.7 +/- 0.1)10(9) (mol/l-1) at 20 degrees C, which was not permitted by other methods. Two lines of evidence supported our assumptions and results. On the one hand, using estradiol as a radioligand instead of dihydrotestosterone, we found the same value for serum TeBG concentration; on the other hand, our assay favourably compared with two different kits commercially available. The correlation (r = 0.89) with 3H-SBP kit Merieux was good though this kit was not suitable for correctly assaying serum TeBG concentrations between 30 nmol/l and 60 nmol/l. An excellent correlation (r = 0.97) with SHBG IRMA Kit Farmos was found. This antibody-based assay and our binding assay yielded quite similar values that mutually validated both methods.


Assuntos
Kit de Reagentes para Diagnóstico , Globulina de Ligação a Hormônio Sexual/análise , Ligação Competitiva , Cromatografia de Afinidade/métodos , Concanavalina A/farmacologia , Di-Hidrotestosterona/farmacologia , Feminino , Humanos , Masculino , Gravidez , Ligação Proteica , Trítio
14.
Anal Biochem ; 159(2): 396-401, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3826624

RESUMO

The authors describe an experimentally simple method for investigating the competition of two ligands for the same binding sites on a protein. The free and bound concentrations of one ligand are modified by the presence of the other; binding isotherms are therefore deformed. The authors present a theoretical study based on the analysis of these isotherms obtained with different known concentrations of the competing ligand. It is shown that deformation of the isotherms can be used to obtain the affinity constant of the competitor. The method was applied to competition between different ligands for the binding sites of testosterone-estradiol-binding globulin, a serum protein specific for the transport of steroid hormones as essential as testosterone and estradiol.


Assuntos
Ligação Competitiva , Ligação Proteica , Sítios de Ligação , Humanos , Masculino , Matemática , Modelos Químicos , Globulina de Ligação a Hormônio Sexual/metabolismo , Termodinâmica
16.
J Immunol ; 137(4): 1187-93, 1986 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3016089

RESUMO

Transferrin (Tf) binding to lymphocytes and to syncytiotrophoblast plasma membranes (STPM) and their soluble extracts (STPM-SE) was examined, as well as the effect of the latter on mitogen-induced lymphoproliferation. Lymphocytes only express Tf receptors (Rtf) after mitogen (phytohemagglutinin or concanavalin A) stimulation, and the percentage of Tf bound by stimulated lymphocytes increased as a function of contact time with the mitogen, reaching a maximum at 72 hr. Studies of Tf binding to STPM-SE showed that the percentage of bound Tf increased proportionally to the protein concentration, but was additionally enhanced by a factor of three when STPM were pretreated with 3 M KCl. Scatchard analysis of Tf binding to lymphocytes cultured for 72 hr in the presence of mitogen, as well as to STPM and STPM-SE, revealed that this binding was specific and occurs via a single category of identical and independent receptors the numbers and affinity constants (Ka) of which have been determined. The results obtained by using STPM indicate that the Ka does not vary significantly from one preparation to another, but that the number of sites per milligram of protein increases by a factor of 10 when the STPM are pretreated with 3 M KCl (KCl-STPM). Finally, STPM-SE inhibited the mitogen-induced lymphoproliferative response whether or not they were treated with 3 M KCl. This inhibition was not due to lymphocytotoxicity, was dose dependent regardless of the preparation used, but was maximized with the KCl-STPM-SE fraction. The correlation between the inhibitory capacities of the soluble STPM extracts and the numbers of RTf sites present on their membranes leads to the hypothesis that the observed inhibition could involve the RTf. This effect may help in protecting the fetus from the maternal immune system at the time of the semi-allogenic fetal graft.


Assuntos
Extratos Celulares/imunologia , Ativação Linfocitária , Receptores de Superfície Celular/fisiologia , Extratos de Tecidos/imunologia , Transferrina/metabolismo , Trofoblastos/imunologia , Ligação Competitiva , Membrana Celular/imunologia , Concanavalina A/farmacologia , Humanos , Cinética , Linfócitos/imunologia , Linfócitos/metabolismo , Proteínas de Membrana/fisiologia , Fito-Hemaglutininas/farmacologia , Cloreto de Potássio/farmacologia , Receptores de Superfície Celular/análise , Receptores de Superfície Celular/biossíntese , Receptores da Transferrina , Trofoblastos/citologia , Trofoblastos/metabolismo
18.
Int J Biochem ; 18(12): 1135-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3817274

RESUMO

A highly sensitive and reproducible radioimmunoassay was established to detect transferrin in human fluids. By this technique, applied to seminal fluid, transferrin levels (micrograms/ml) were found in normozoospermic individuals (64.49 +/- 25.41) at level higher than in oligozoospermic (38.93 +/- 21.35), azoospermic (19.49 +/- 10.23), or vasectomized (19.61 +/- 8.95) subjects. A relationship between transferrin and spermatozoid concentration in sperm was shown. These results reinforce previous findings that seminal transferrin can be used as a reliable clinical marker of Sertoli Cell function.


Assuntos
Líquidos Corporais/análise , Sêmen/análise , Transferrina/análise , Técnicas de Laboratório Clínico , Humanos , Masculino , Oligospermia/metabolismo , Radioimunoensaio/métodos , Valores de Referência , Vasectomia
20.
Rev Fr Transfus Immunohematol ; 25(1): 49-55, 1982 Feb.
Artigo em Francês | MEDLINE | ID: mdl-7041224

RESUMO

A one year study has been performed between six blood Banks of the Centre of France in order to evaluate, among a population of donors found to be positive for HBs Ag by a radioimmunoassay, the number of those who were not detected by Enzyme immunoassay or passive hemagglutination. This study provides a good basis for comparing the sensitivities of the different methods used for Hbs Ag testing.


Assuntos
Bancos de Sangue , Antígenos de Superfície da Hepatite B/análise , França , Testes de Hemaglutinação , Anticorpos Anti-Hepatite B/análise , Humanos , Técnicas Imunoenzimáticas , Radioimunoensaio
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