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1.
Neoplasma ; 67(6): 1437-1446, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32787435

RESUMEN

Radiomics focuses on extracting a large number of quantitative imaging features and testing both their correlation with clinical characteristics and their prognostic and predictive values. We propose a radiomic approach using magnetic resonance imaging (MRI) to decode the tumor phenotype and local recurrence in oropharyngeal squamous cell carcinoma (OPSCC). The contrast-enhanced T1-weighted sequences from baseline MRI examinations of OPSCC patients treated between 2008 and 2016 were retrospectively selected. Radiomic features were extracted using the IBEX software, and hiegrarchical clustering was applied to reduce features redundancy. The association of each radiomic feature with tumor grading and stage, HPV status, loco-regional recurrence within 2 years, considered as main endpoints, was assessed by univariate analysis and then corrected for multiple testing. Statistical analysis was performed with SAS/STAT® software. Thirty-two eligible cases were identified. For each patient, 1286 radiomic features were extracted, subsequently grouped into 16 clusters. Higher grading (G3 vs. G1/G2) was associated with lower values of GOH/65Percentile and GOH/85Percentile features (p=0.04 and 0.01, respectively). Positive HPV status was associated with higher values of GOH/10Percentile (p=0.03) and lower values of GOH/90Percentile (p=0.03). Loco-regional recurrence within 2 years was associated with higher values of GLCM3/4-7Correlation (p=0.04) and lower values of GLCM3/2-1InformationMeasureCorr1 (p=0.04). Results lost the statistical significance after correction for multiple testing. T stage was significantly correlated with 9 features, 4 of which (GLCM25/180-4InformationMeasureCorr2, Shape/MeanBreadth, GLCM25/90-1InverseDiffMomentNorm, and GLCM3/6-1InformationMeasureCorr1) retained statistical significance after False Discovery Rate correction. MRI-based radiomics is a feasible and promising approach for the prediction of tumor phenotype and local recurrence in OPSCC. Some radiomic features seem to be correlated with tumor characteristics and oncologic outcome however, larger collaborative studies are warranted in order to increase the statistical power and to obtain robust and validated results.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia , Neoplasias Orofaríngeas/diagnóstico por imagen , Humanos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Pronóstico , Estudios Retrospectivos
2.
Strahlenther Onkol ; 193(11): 971-981, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28884310

RESUMEN

PURPOSE: Acute toxicity in head and neck (H&N) cancer patients treated with definitive radiotherapy (RT) has a crucial role in compliance to treatments. The aim of this study was to correlate doses to swallowing-associated structures and acute dysphagia. METHODS: We prospectively analyzed 42 H&N cancer patients treated with RT. Dysphagia (grade ≥ 3) and indication for percutaneous endoscopic gastrostomy (PEG) insertion were classified as acute toxicity. Ten swallowing-related structures were considered for the dosimetric analysis. The correlation between clinical information and the dose absorbed by the contoured structures was analyzed. Multivariate logistic regression method using resampling methods (bootstrapping) was applied to select model order and parameters for normal tissue complication probability (NTCP) modelling. RESULTS: A strong multiple correlation between dosimetric parameters was found. A two-variable model was suggested as the optimal order by bootstrap method. The optimal model (Rs = 0.452, p < 0.001) includes V45 of the cervical esophagus (odds ratio [OR] = 1.016) and Dmean of the cricopharyngeal muscle (OR = 1.057). The model area under the curve was 0.82 (95% confidence interval 0.69-0.95). CONCLUSION: Our results suggested that the absorbed dose to the cricopharyngeal muscle and cervical esophagus might play a relevant role in the development of acute RT-related dysphagia.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Trastornos de Deglución/etiología , Deglución/efectos de la radiación , Neoplasias de Oído, Nariz y Garganta/radioterapia , Traumatismos por Radiación/etiología , Adulto , Anciano , Trastornos de Deglución/terapia , Nutrición Enteral , Esófago/efectos de la radiación , Femenino , Gastrostomía , Humanos , Masculino , Persona de Mediana Edad , Músculos Faríngeos/efectos de la radiación , Estudios Prospectivos , Traumatismos por Radiación/terapia , Dosificación Radioterapéutica , Estadística como Asunto
3.
Oral Oncol ; 157: 106950, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038413

RESUMEN

INTRODUCTION: Immune checkpoint inhibitors (ICIs) have demonstrated efficacy in the treatment of recurrent and/or metastatic (RM) head and neck squamous cell carcinoma (HNSCC) Keynote 048 highlighted the relevance of PD-L1 Combined Positive Score (CPS) as a predictive biomarker for ICIs treatment, but challenges persist regarding ideal assessment and concordance between primary and relapsing tumor has not been determined. MATERIAL AND METHODS: This is a retrospective multicentric study that included HNSCC patients with locoregional and/or metastatic relapses after curative treatment. Histological samples of primary tumors and corresponding relapses were collected. The primary objective was to evaluate PD-L1 CPS concordance between primary and recurrent tumors, with secondary objective of exploring the impact of clinical-pathological variables. RESULTS: Out of 86 evaluated patients, 30 cases were excluded due to insufficient histological material, with a final enrollment of 56 patients. Concordance analysis revealed a 66.1% agreement in PD-L1 CPS between primary and recurrent tumors. Only 3.6% of cases exhibited a change from negative to positive PD-L1 CPS status, and 7.2% showed the reverse. Factors analyzed, including primary tumor site, treatment modality, and recurrence type, did not significantly influence PD-L1 CPS concordance level. CONCLUSION: While significant changes in PD-L1 CPS expression are rare, the study underscores the importance of confirmatory biopsies on relapse. However, reliance on archival tumor tissue for initial PDL1 assessment may be considered in cases where obtaining additional biopsies poses risks to patients or urgent therapeutic decisions are required.


Asunto(s)
Antígeno B7-H1 , Neoplasias de Cabeza y Cuello , Recurrencia Local de Neoplasia , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Antígeno B7-H1/metabolismo , Masculino , Estudios Retrospectivos , Femenino , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/metabolismo , Anciano , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/metabolismo , Adulto , Anciano de 80 o más Años , Metástasis de la Neoplasia , Biomarcadores de Tumor/metabolismo
4.
Hematol Oncol ; 31(1): 34-40, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22473680

RESUMEN

High-dose chemotherapy (HDCT) has a consolidated role in the treatment of patients with refractory or relapsed Hodgkin lymphoma (HL). We report clinical results of 97 HL patients who underwent HDCT for refractory (62 patients) or relapsed (35 patients) diseases in Istituto Europeo di Oncologia, from 1995 to 2009. Treatment included high-dose carmustine, etoposide, cytarabine and melphalan in 84 patients and high-dose idarubicin and melphalan in 13 patients with subsequent peripheral hemopoietic stem cells transplant. Outcomes were evaluated in terms of progression-free survival (PFS) and overall survival (OS). In order to identify prognostic factors for outcome, a multivariate analysis for age, sex, disease status (refractory/relapsed), disease stage, B symptoms, presence of extranodal involvement, bulky disease, elevated lactate dehydrogenase, number of previous chemotherapy lines, remission status before transplant, 18F-fluoro-deoxy-d-glucose positron emission tomography ((18) FDG-PET) status before and after transplant was done. A clinical response was achieved in 91% of patients, with complete remissions in 76/97 patients. With a median follow-up of 45 months (range 1-164 months), 5-year PFS and OS were 64% and 71%, respectively. Remission status after induction therapy, 18F-fluoro-deoxy-d-glucose positron emission tomography status before and after transplant were the most important prognostic factors for PFS and OS in univariate or multivariate analyses. HDCT is able to induce a high remission rate and a prolonged PFS in more than 50% of the patients with refractory and relapsed HL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Tomografía de Emisión de Positrones , Terapia Recuperativa , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Trasplante de Médula Ósea , Cisplatino/administración & dosificación , Terapia Combinada , Citarabina/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Dexametasona/administración & dosificación , Supervivencia sin Enfermedad , Etopósido/administración & dosificación , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Enfermedad de Hodgkin/diagnóstico por imagen , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/cirugía , Humanos , Ifosfamida/administración & dosificación , Estimación de Kaplan-Meier , Masculino , Metilprednisolona/administración & dosificación , Persona de Mediana Edad , Estadificación de Neoplasias , Trasplante de Células Madre de Sangre Periférica , Pronóstico , Radiofármacos , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Trasplante Autólogo , Resultado del Tratamiento , Vinblastina/administración & dosificación , Vinblastina/análogos & derivados , Vinorelbina , Adulto Joven , Gemcitabina
5.
Radiol Med ; 116(4): 548-63, 2011 Jun.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21225365

RESUMEN

PURPOSE: This study assessed the risk factors for pneumothorax and intrapulmonary haemorrhage after computed tomography (CT)-guided lung biopsies. MATERIALS AND METHODS: CT-guided lung biopsies performed between January 2007 and July 2008 were retrospectively evaluated to select the study cohort. Whenever possible, emphysema was quantified by using dedicated software. Features related to the patient, the lesion and the needle and its intrapulmonary path were recorded, along with the pathology findings and operators' experience. The occurrence of pneumothorax and parenchymal haemorrhage was recorded. Univariate and multivariate statistical analyses were performed to assess the association between risk factors and complications. P values <0.05 were considered significant. RESULTS: In 157/222 of the procedures considered, complications were associated with small lesion size and length of the intrapulmonary needle path. Transfissural course and type of needle were associated with pneumothorax using univariate analysis, whereas transfissural course was associated with intrapulmonary haemorrhage using both univariate and multivariate analysis. Emphysema, nodule type, patient position, access site and needle diameter were not significant. Fine-needle aspirates and operator experience were significantly correlated with inadequate biopsy samples. CONCLUSIONS: The size of the lesion and the length of the intrapulmonary trajectory are risk factors for pneumothorax and parenchymal haemorrhage. The transfissural course of the needles is frequently related to pneumothorax and intrapulmonary haemorrhage, and the type of the needle is related to pneumothorax.


Asunto(s)
Biopsia con Aguja/efectos adversos , Pulmón/patología , Radiografía Intervencional , Tomografía Computarizada por Rayos X , Femenino , Hemorragia/etiología , Humanos , Enfermedades Pulmonares/etiología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Neumotórax/etiología , Enfisema Pulmonar/diagnóstico por imagen , Factores de Riesgo
6.
Radiol Med ; 116(3): 466-76, 2011 Apr.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21225368

RESUMEN

PURPOSE: This study evaluated intraobserver and interobserver variability in the measurement of apparent diffusion coefficient (ADC) values in breast carcinomas. MATERIALS AND METHODS: Twenty-eight patients with solid breast lesions >10 mm underwent conventional contrast-enhanced magnetic resonance imaging (MRI) and diffusion-weighted MRI (DW-MRI). Two observers (expert and trainee) segmented the lesion from the surrounding breast tissue on DW images with high b-value (1,000 s/mm(2)). This analysis was repeated by the expert reader after 6 months. Volumes were analysed to obtain mean, median and standard deviation (SD) of the ADC values. Interobserver and intraobserver variation was analysed using the Bland-Altman graph. RESULTS: All lesions were breast carcinomas, with a mean ADC value of 1.07 × 10(-3) mm(2)/s. The mean of the differences was 0.012 × 10(-3) mm(2)/s, corresponding to an intraobserver variability of 1.1% (limits of agreement: -5%/+8%). The mean interobserver difference was 0.022 × 10(-3) mm(2)/s, corresponding to an interobserver variability of 2% (limits of agreement: -9%/+14%). CONCLUSIONS: We found a low intraobserver and interobserver variability in calculating ADC in breast carcinomas, which supports its potential use in routine clinical practice.


Asunto(s)
Neoplasias de la Mama/patología , Imagen de Difusión por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Variaciones Dependientes del Observador
7.
Radiol Med ; 115(6): 858-74, 2010 Sep.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20221706

RESUMEN

Perfusion computed tomography (CTP) has shown great potential in diagnosing tumours and evaluating and predicting treatment response and has been the subject of numerous experimental and clinical studies. Its increasing availability and simplicity allow it to be performed alongside morphological imaging to complete the evaluation of neoplastic lesions. The aim of this paper is to describe our personal experience and review the literature on the applications of CTP in tumours of different body regions, with particular regard to fields of development for new research. Increased clinical application is desirable, especially in relation to a wider use of antiangiogenic drugs. Additional and ideally multicentre studies are necessary to define the role of this technique.


Asunto(s)
Neoplasias/diagnóstico por imagen , Imagen de Perfusión/métodos , Tomografía Computarizada por Rayos X/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Femenino , Neoplasias de los Genitales Femeninos/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Neoplasias/terapia , Neoplasias de Oído, Nariz y Garganta/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Valor Predictivo de las Pruebas , Neoplasias de la Próstata/diagnóstico por imagen , Sensibilidad y Especificidad
8.
Radiol Med ; 115(6): 843-57, 2010 Sep.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20177989

RESUMEN

Functional imaging is becoming increasingly important in both research and clinical diagnostic radiology. Perfusion computed tomography (CTP) is a readily available and widely used tool that allows an objective measurement of tissue perfusion through the mathematical analysis of data obtained from repeated scans performed after administration of contrast agent. Recently, CTP has been increasingly used in the oncological field, being studied as a potential marker of neoplastic angiogenesis, which is one of the main targets of new tumour therapies. The aim of this paper was to provide the theoretical background and practical guidance for accurately performing CTP and interpreting results of examinations in solid-body tumours. CTP could be a valid tool for functional imaging of tumours if the acquisition technique is robust, if image and data analysis is accurate and if interpretation of results is adequately inserted within a clinical context.


Asunto(s)
Neoplasias/diagnóstico por imagen , Imagen de Perfusión/métodos , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Radioisótopos de Yodo , Cinética , Estadificación de Neoplasias , Imagen de Perfusión/instrumentación , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Programas Informáticos
9.
Phys Med ; 69: 164-169, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31918368

RESUMEN

PURPOSE: To devise a novel Spatial Normalization framework for Voxel-based analysis (VBA) in brain radiotherapy. VBAs rely on accurate spatial normalization of different patients' planning CTs on a common coordinate system (CCS). The cerebral anatomy, well characterized by MRI, shows instead poor contrast in CT, resulting in potential inaccuracies in VBAs based on CT alone. METHODS: We analyzed 50 meningioma patients treated with proton-therapy, undergoing planning CT and T1-weighted (T1w) MRI. The spatial normalization pipeline based on MR and CT images consisted in: intra-patient registration of CT to T1w, inter-patient registration of T1w to MNI space chosen as CCS, doses propagation to MNI. The registration quality was compared with that obtained by Statistical Parametric Mapping software (SPM), used as benchmark. To evaluate the accuracy of dose normalization, the dose organ overlap (DOO) score was computed on gray matter, white matter and cerebrospinal fluid before and after normalization. In addition, the trends in the DOOs distribution were investigated by means of cluster analysis. RESULTS: The registration quality was higher for the proposed method compared to SPM (p < 0.001). The DOO scores showed a significant improvement after normalization (p < 0.001). The cluster analysis highlighted 2 clusters, with one of them including the majority of data and exhibiting acceptable DOOs. CONCLUSIONS: Our study presents a robust tool for spatial normalization, specifically tailored for brain dose VBAs. Furthermore, the cluster analysis provides a formal criterion for patient exclusion in case of non-acceptable normalization results. The implemented framework lays the groundwork for future reliable VBAs in brain irradiation studies.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de la radiación , Meningioma/diagnóstico por imagen , Meningioma/radioterapia , Adolescente , Adulto , Anciano , Análisis por Conglomerados , Medios de Contraste/química , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Persona de Mediana Edad , Modelos Estadísticos , Radiometría , Reproducibilidad de los Resultados , Programas Informáticos , Tomografía Computarizada por Rayos X , Adulto Joven
10.
Radiol Med ; 114(6): 915-24, 2009 Sep.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-19562266

RESUMEN

PURPOSE: Primary lymphomas of the breast (PBNHL) are uncommon. Magnetic resonance imaging (MRI) features of these malignancies can be relevant in establishing the extent of disease and planning the appropriate therapeutic strategy, usually represented by chemo- and radiotherapy, rather than surgery. The purpose of this study was to assess MRI features of PBNHL. MATERIALS AND METHODS: MRI examinations performed on seven patients with known PBNHL were retrospectively evaluated. Lesions were analysed for both morphology and kinetics and classified according to the Breast Imaging Reporting and Data System (BI-RADS) categories. RESULTS: The mean MRI maximum diameter was 44 mm (range 12-69). Six lesions showed a mass-like enhancement; one lesion showed a non-mass-like enhancement. For mass-like lesions, kinetic curve assessment of initial rise showed slow enhancement in one lesion, rapid enhancement in four lesions and medium enhancement in one lesion. Assessment of delayed enhancement showed plateau in five lesions and washout in one lesion. MRI BI-RADS categories were distributed as follows: one BI-RADS II, one BI-RADS III, three BI-RADS IV and two BI-RADS V. CONCLUSIONS: MRI features of primary breast lymphomas in this study cohort suggest that the occurrence of a PBNHL should be considered in the presence of large enhancing lesions of the breast, especially if associated with skin thickening. MRI may also have an important role in the assessment of response to therapy and diagnosis of recurrence.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Linfoma/diagnóstico , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Neoplasias de la Mama/patología , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Linfoma/patología , Persona de Mediana Edad , Estudios Retrospectivos
11.
Head Neck Pathol ; 13(4): 686-691, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29876739

RESUMEN

Mammary analogue secretory carcinoma (MASC) is a recently described low-grade salivary gland malignancy with histologic, immunohistochemical and molecular similarities to secretory carcinoma of the breast, including a specific t(12;15)(p13;q25) resulting in an ETV6-NTRK3 gene fusion. Ultrasound and magnetic resonance imaging frequently document a macrocystic structure. The main differential diagnosis of secretory carcinoma is with low grade acinic cell carcinoma (AciCC). The two can be differentiated with immunohistochemical stains for S100, mammaglobin, carbonic anhydrase VI and DOG-1; the identification of the specific translocation can help to characterize non-typical cases. We report a unique case of synchronous MASC and AciCC presenting in a parotid gland and discuss the implications of the correct identification of the two tumors.


Asunto(s)
Carcinoma de Células Acinares/patología , Carcinoma Secretor Análogo al Mamario/patología , Neoplasias Primarias Múltiples/patología , Neoplasias de la Parótida/patología , Femenino , Humanos , Persona de Mediana Edad
12.
Med Oncol ; 34(5): 86, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28391578

RESUMEN

Many concerns are related to the idea that the acute toxicity of induction chemotherapy (IC) performed with TPF (docetaxel, cisplatin, 5-fluorouracil) could reduce the ability to deliver the subsequent standard concurrent chemoradiotherapy (CRT) in head and neck cancer patients. We performed a critical review of the literature on the toxicity profile of the standard CRT administered after the IC with TPF. A total of 13 papers (including 950 patients) were selected. Results showed that most patients were treated with an adequate radiation total dose although a significant proportion of them (from 15 to 30%) completed the planned treatment with a delay of more than 5 days. A minority of patients were able to be treated with three cycles of concurrent cisplatin, but only few papers reported how many of patients reached the cumulative total dose of almost 200 mg/m2 cisplatin. The rate of deaths due to treatment-related toxicity varied from 0 to 9% (median and mean 2%). Two prospective trials stopped patient enrollment due to acute treatment-related toxicity and because a low number of patients were able to undergo the planned full schedule of cisplatin during the CRT, respectively. Retrospective analysis of 45 patients treated at our institute showed that this schedule was feasible with manageable side effects. In conclusion, the literature data did not provide homogeneous information on the feasibility of the standard CRT after induction TPF. A more uniform data collection of treatment-related toxicity will be helpful in better selecting the patients who might adequately tolerate this multimodality strategy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioradioterapia , Cisplatino/administración & dosificación , Docetaxel , Estudios de Factibilidad , Fluorouracilo/administración & dosificación , Humanos , Estudios Retrospectivos , Taxoides/administración & dosificación
13.
Psychopharmacology (Berl) ; 110(4): 421-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7870912

RESUMEN

The scopolamine model of amnesia has been used to test the pharmacodynamic efficacy of oxiracetam in 12 healthy volunteers. The subjects were divided into four experimental groups, according to a double-blind cross over incomplete randomized block design. After a baseline neuropsychological examination, each subject received in two separate sessions one of the following treatments, as acute oral doses: oxiracetam 800, 1600, 2400 mg or placebo. One hour after treatment scopolamine hydrobromide (0.5 mg) was given subcutaneously. The cognitive performance was tested before and 1, 2, 3 and 25 h after scopolamine administration. Scopolamine caused a deterioration of performance of verbal episodic memory, semantic memory and attention tests. In comparison to placebo, oxiracetam improved the overall test performance, with a statistically significant difference at the dose of 1600 mg on delayed recall of word lists, and showed dose-related antagonism of scopolamine-induced effects also on semantic memory and attention. The efficacy of an acute dose of oxiracetam in reducing scopolamine-induced cognitive impairment supports the potential usefulness of this pharmacological model of amnesia for studying the effects of cognition enhancers in humans.


Asunto(s)
Amnesia/psicología , Psicotrópicos/farmacología , Pirrolidinas/farmacología , Escopolamina/antagonistas & inhibidores , Adulto , Amnesia/inducido químicamente , Atención/efectos de los fármacos , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Memoria/efectos de los fármacos , Memoria a Corto Plazo/efectos de los fármacos , Recuerdo Mental/efectos de los fármacos , Pruebas Neuropsicológicas , Lectura , Escopolamina/farmacología
14.
Thromb Res ; 64(6): 647-58, 1991 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1839200

RESUMEN

Using an ACL 300R coagulometer (Instrumentation Laboratory) we assessed the clinical usefulness of a new method to measure PS activity (PS:Act), based on the prolongation of prothrombin time of a mixture of diluted plasma sample, PS depleted plasma previously incubated with Protac for protein C activation, bovine thromboplastin and calcium ions. The results were compared with those from immunological assays. PS:Act was measured in 42 apparently healthy subjects, in 12 patients with hereditary PS deficiency (HPSD group) diagnosed on the basis of immunologic tests and in 48 patients with episodes of juvenile venous thromboembolism at least three months prior to testing (JVTE group). All the HPSD patients had PS:Act below the normal range (less than 62%). In JVTE group 9 patients (18.7%) showed abnormal results for PS:Act, 4 (8.3%) had low levels of free PS:Ag; all patients had normal total PS:Ag levels. Levels of antiphospholipid antibodies (immunologic test) were normal in the 9 JVTE patients with low PS:Act. When all the results were considered together (n = 102), the correlation coefficient between PS:Act and free PS:Ag was 0.78 (p less than 0.01).


Asunto(s)
Proteínas Sanguíneas/metabolismo , Glicoproteínas/metabolismo , Tromboflebitis/sangre , Adolescente , Adulto , Análisis Químico de la Sangre/métodos , Proteínas Sanguíneas/deficiencia , Proteínas Sanguíneas/genética , Glicoproteínas/deficiencia , Glicoproteínas/genética , Humanos , Masculino , Persona de Mediana Edad , Proteína S , Tiempo de Protrombina , Valores de Referencia , Reproducibilidad de los Resultados
15.
Thromb Res ; 52(5): 453-68, 1988 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-3146823

RESUMEN

A new family of coagulometers ACL 100, 200 and 300 (Instrumentation Laboratory, IL) has recently been introduced, in addition to the existing ACL 810. This paper presents a technique to determine clottable fibrinogen using the ACL method based on the measurement of the light scattered from the reaction mixture during a PT test. This technique was found to compare well with the present most commonly used methods.


Asunto(s)
Análisis Químico de la Sangre/instrumentación , Pruebas de Coagulación Sanguínea/instrumentación , Fibrinógeno/análisis , Afibrinogenemia/sangre , Análisis Químico de la Sangre/métodos , Pruebas de Coagulación Sanguínea/métodos , Estudios de Evaluación como Asunto , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Heparina/sangre , Humanos , Inmunodifusión , Tiempo de Protrombina
16.
Thromb Res ; 86(6): 461-8, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9219326

RESUMEN

A functional clotting assay was recently reported to detect the factor V-Leiden mutation (R506Q) in patients receiving oral anticoagulants and in patients with Lupus Anticoagulant inhibitor. The original assay (Dahlback) to detect resistance to activated protein C (aPC-resistance) frequently gave unreliable findings in these patients. The change in the method is the use of bovine thromboplastin in a PT-derived assay, with a 1:10 sample dilution. In these conditions a reference normal plasma gives a prolongation of more than 35 seconds, while samples with a heterozygous or homozygous mutation give a prolongation respectively of 10-18 seconds or less 2 seconds. The test is easily automated and quickly performed on ACL/3000, and the reproducibility is good.


Asunto(s)
Pruebas de Coagulación Sanguínea/métodos , Factor V/análisis , Factor V/efectos de los fármacos , Proteína C/farmacología , Animales , Anticoagulantes/farmacología , Trastornos de la Coagulación Sanguínea/sangre , Trastornos de la Coagulación Sanguínea/diagnóstico , Trastornos de la Coagulación Sanguínea/genética , Pruebas de Coagulación Sanguínea/estadística & datos numéricos , Bovinos , Resistencia a Medicamentos , Estudios de Evaluación como Asunto , Factor V/genética , Factor VIII/metabolismo , Heparina/farmacología , Heterocigoto , Homocigoto , Humanos , Técnicas In Vitro , Inhibidor de Coagulación del Lupus/efectos de los fármacos , Mutación Puntual , Conejos , Reproducibilidad de los Resultados , Tromboplastina
17.
Thromb Res ; 68(6): 451-7, 1992 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1341055

RESUMEN

The inhibitory capacity of the natural protein C (PC)/protein S (PS) system was evaluated measuring both the functional activity and the antigen level of both these inhibitors in 30 uremic patients before and after a dialytic treatment and in 30 healthy normal volunteers. PC functional activity was determined by two methods, one clotting and one chromogenic. PS antigen level was measured both as free protein and as total content. Unlike previous authors, we found that PC functional activity and the antigen level were normal in patients before dialysis, with a significant increase after. PS functional activity and free and total antigen levels were all normal before dialysis, and all except free antigen showed a significant post-treatment rise.


Asunto(s)
Proteína C/análisis , Proteína S/análisis , Diálisis Renal , Uremia/sangre , Pruebas de Coagulación Sanguínea , Humanos , Tromboembolia/etiología , Uremia/complicaciones , Uremia/terapia
18.
Thromb Res ; 60(1): 19-32, 1990 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2148988

RESUMEN

Protein S activity was measured as the degree of prolongation of a prothrombin time-based clotting assay in which diluted test sample, protein S-depleted plasma previously incubated with Protac to fully activate protein C, bovine thromboplastin and calcium ions are mixed. Assay specificity was first demonstrated by observing that the prolongation of the clotting time was dependent on protein S and was subsequently confirmed by testing plasma samples from patients with conditions known to affect protein S activity. High sensitivity, reproducibility (interassay coefficient of variation lower than 5%) and easy handling of samples and reagents make this assay suitable for screening of congenital and acquired protein S deficiency.


Asunto(s)
Análisis Químico de la Sangre/métodos , Glicoproteínas/sangre , Tiempo de Protrombina , Anticoagulantes/uso terapéutico , Femenino , Glicoproteínas/deficiencia , Humanos , Cirrosis Hepática/sangre , Masculino , Embarazo , Proteína C/metabolismo , Proteína S , Valores de Referencia
19.
Thromb Res ; 65(2): 253-62, 1992 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1533734

RESUMEN

Protein C (PC) and protein S (PS) are components of a potent, natural anticoagulant system. A deficiency of one of these two inhibitors is associated with thrombotic events in young people. A significant reduction in functional PS activity has been observed during normal pregnancy, and recurrent fetal loss may occur in women with lupus anticoagulant (LA) inhibitor. We measured functional PS activity and free PS antigen in 16 non pregnant patients with LA inhibitor and in 17 normal women as controls. A significant difference was observed between patients and controls in functional PS activity (65 +/- 23% vs 87 +/- 15%, p = 0.02) but not in free PS antigen (88 +/- 17% vs 93 +/- 17%). Functional PS activity decreased only in six patients (37%). Removal of IgG from plasma reduced the difference in functional PS activity between patients and controls. Immunologic IgG levels did not correlate with anti-phospholipid antibodies (APA) activities, activated partial thromboplastin time/kaolin clotting time (aPTT/KCT) data or functional PS activity.


Asunto(s)
Aborto Habitual/sangre , Proteínas Sanguíneas/metabolismo , Glicoproteínas/sangre , Inhibidor de Coagulación del Lupus/sangre , Tromboembolia/sangre , Adsorción , Adulto , Antígenos/sangre , Femenino , Glicoproteínas/inmunología , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , Embarazo , Proteína S , Valores de Referencia
20.
Blood Coagul Fibrinolysis ; 12(5): 405-10, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11505085

RESUMEN

We developed a new simple test to evaluate the global function of the activated factor II-antithrombin system. The new test measures the clotting time of plasma samples after the addition of a reagent containing a snake venom (Echis carinatus) that can activate prothrombin, with (Ta) and without (To) heparin. The prolongation of clotting times (Ta - To) is directly related to the function of the activated factor II-antithrombin system. The presence of quantitative or functional defects of the natural inhibitors (antithrombin and heparin co-factor II), or high levels of factor II and/or fibrinogen, can trigger a resistance to the inhibition of activated factor II. This new test was used to examine 134 thrombophilic patients as well as 157 normal subjects as controls. The results obtained confirm that the presence of abnormalities relating to the activated factor II-antithrombin system causes a resistance to activated factor II inhibition even if a significant number of patients was found to have a resistance that could not be accounted for. Since the new test can be easily performed automatically and has a good inter- and intra-assay variation coefficient (CV < 4%) it is useful for evaluating the global function of the activated factor II-antithrombin system in screening thrombophilic patients, alongside the tests already known and used to diagnose these patients.


Asunto(s)
Antitrombinas/fisiología , Coagulación Sanguínea/efectos de los fármacos , Protrombina/fisiología , Antitrombinas/farmacología , Pruebas de Coagulación Sanguínea/métodos , Pruebas de Coagulación Sanguínea/normas , Estudios de Casos y Controles , Relación Dosis-Respuesta a Droga , Factor VIII/farmacología , Femenino , Heparina/farmacología , Humanos , Masculino , Tamizaje Masivo , Métodos , Protrombina/antagonistas & inhibidores , Protrombina/efectos de los fármacos , Protrombina/metabolismo , Protrombina/farmacología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Venenos de Serpiente/farmacología , Trombofilia/sangre
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