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1.
Eur Radiol ; 30(12): 6441-6451, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32683551

RESUMEN

OBJECTIVES: We aimed to evaluate the ability of feed-forward neural networks (fNNs) to predict the neurodevelopmental outcome (NDO) of very preterm neonates (VPIs) at 12 months corrected age by using biomarkers of cerebral MR proton spectroscopy (1H-MRS) and diffusion tensor imaging (DTI) at term-equivalent age (TEA). METHODS: In this prospective study, 300 VPIs born before 32 gestational weeks received an MRI scan at TEA between September 2013 and December 2017. Due to missing or poor-quality spectroscopy data and missing neurodevelopmental tests, 173 VPIs were excluded. Data sets consisting of 103 and 115 VPIs were considered for prediction of motor and cognitive developmental delay, respectively. Five metabolite ratios and two DTI characteristics in six different areas of the brain were evaluated. A feature selection algorithm was developed for receiving a subset of characteristics prevalent for the VPIs with a developmental delay. Finally, the predictors were constructed employing multiple fNNs and fourfold cross-validation. RESULTS: By employing the constructed fNN predictors, we were able to predict cognitive delays of VPIs with 85.7% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 99.1% negative predictive value (NPV). For the prediction of motor delay, we achieved a sensitivity of 76.9%, a specificity of 98.9%, a PPV of 90.9% and an NPV of 96.7%. CONCLUSION: FNNs might be able to predict motor and cognitive development of VPIs at 12 months corrected age when employing biomarkers of cerebral 1H-MRS and DTI quantified at TEA. KEY POINTS: • A feed-forward neuronal network is a promising tool for outcome prediction in premature infants. • Cerebral proton magnetic resonance spectroscopy and diffusion tensor imaging can be used for the construction of early prognostic biomarkers. • Premature infants that would most benefit from early intervention services can be spotted at the time of optimal neuroplasticity.


Asunto(s)
Encéfalo/diagnóstico por imagen , Discapacidades del Desarrollo/diagnóstico , Imagen de Difusión Tensora/métodos , Interpretación de Imagen Asistida por Computador/métodos , Enfermedades del Prematuro/diagnóstico , Espectroscopía de Resonancia Magnética/métodos , Redes Neurales de la Computación , Encéfalo/fisiopatología , Discapacidades del Desarrollo/fisiopatología , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/fisiopatología , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Sensibilidad y Especificidad
2.
Eur J Gynaecol Oncol ; 37(3): 434-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27352582

RESUMEN

INTRODUCTION: Metastatic renal cell carcinoma is often found in distant organs, including lung, bone, brain, and liver. Metastases to the vagina are extremely rare. CASE REPORT: The authors present a case of renal cell carcinoma metastasis to the anterior vaginal wall four months after nephrectomy in a 56-year-old patient. The vaginal lesions were excised. After two years the patient had no signs of recurrence or the disease progression. CONCLUSION: Vaginal metastases should be considered in differential diagnosis of female renal cell carcinoma patients presenting with vaginal bleeding of mass.


Asunto(s)
Carcinoma de Células Renales/secundario , Neoplasias Renales/patología , Neoplasias Vaginales/secundario , Carcinoma de Células Renales/patología , Femenino , Humanos , Persona de Mediana Edad
3.
Clin Exp Obstet Gynecol ; 43(1): 63-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27048020

RESUMEN

PURPOSE: The objectives of this study were as follows: to present the course and outcome of pregnancies complicated with fetal ventriculomegaly, determine the association between prenatal ultrasound diagnoses and definitive postnatal diagnosis or diagnoses after autopsy and additional analysis, and to monitor the psychomotor development of children born with ventriculomegaly. MATERIALS AND METHODS: The survey was designed as retrospective study and included 62 pregnant women who were attending a regular ultrasound examinations at the Department of Gynecology and Obstetrics, Clinical Center of Serbia, or patients who were referred from other institutions in Serbia. RESULTS: Ventriculomegalies were divided into three groups: mild, moderate, and severe or hydrocephalus. The most common were severe ventriculomegalies, with 34 cases (55%). Of all pregnancies complicated with ventriculomegalies, 61% were terminated. Among those continued, 88% had normal psychomotor development. In 97% ultrasonographic diagnosis was confirmed. CONCLUSION: Majority of pregnancies complicated with ventriculomegaly were continued and most of the children born with anomalies had normal psychomotor development.


Asunto(s)
Ventrículos Cerebrales/anomalías , Ventrículos Cerebrales/diagnóstico por imagen , Enfermedades Fetales/diagnóstico por imagen , Trastornos Psicomotores/fisiopatología , Desempeño Psicomotor/fisiología , Ultrasonografía Prenatal/métodos , Adulto , Ventrículos Cerebrales/embriología , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Recién Nacido , Embarazo , Trastornos Psicomotores/etiología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
4.
Clin Exp Obstet Gynecol ; 42(1): 57-61, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25864283

RESUMEN

PURPOSE: The objectives of this study were as follows: to present the course and outcome of pregnancies complicated with neural tube defects, determine the association between prenatal ultrasound diagnoses, and definitive diagnoses after autopsy. MATERIAL AND METHODS: The survey was designed as a retrospective study and included 24 pregnant women who were attending a regular ultrasound examinations at the Department of Gynecology and Obstetrics, Clinical Center of Serbia, or patients who were referred from other institutions in Serbia. RESULTS: Neural tube defects are divided into five subgroups: spina bifida, meningocele, myelomeningocele, acranius, and anencephaly. The most frequent in the present study was spina bifida with 67%. All pregnancies complicated with neural tube defects were terminated. CONCLUSION: Their clinical severity and uncertain cause make them priorities for further research, whether to better target primary preventive measures, to improve in-utero surgery for prenatal repair, or to identify the causative genes to provide an objective basis for individual genetic counselling.


Asunto(s)
Defectos del Tubo Neural , Complicaciones del Embarazo , Ultrasonografía Prenatal/métodos , Feto Abortado/patología , Aborto Inducido/estadística & datos numéricos , Adulto , Femenino , Humanos , Evaluación de Necesidades , Defectos del Tubo Neural/clasificación , Defectos del Tubo Neural/diagnóstico , Defectos del Tubo Neural/terapia , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/terapia , Resultado del Embarazo , Diagnóstico Prenatal/métodos , Estudios Retrospectivos , Serbia
5.
Eur J Gynaecol Oncol ; 34(3): 280-1, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23967567

RESUMEN

Endometrial stromal sarcoma (ESS) is a rare uterine neoplasm. Tumor involvement of the large vessels is extremely rare. This is a case report of ESS with tumor invasion of the inferior vena cava at initial presentation.


Asunto(s)
Neoplasias Endometriales/patología , Sarcoma Estromático Endometrial/patología , Vena Cava Inferior/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad
6.
J Mol Histol ; 44(1): 55-63, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23070517

RESUMEN

Distributions of the Ki-67, TP53, caspase-3 and AIFM1 markers were histologically investigated in the 5th to 9th week developing gonads of 12 human conceptuses using immunohistochemical and immunofluorescence methods. Between the 5th and 8th developmental week, proliferation gradually increased in the surface gonad epithelium (26-52 %) and stroma (19-42 %), but then slightly decreased in the surface epithelium (35 %) during the early foetal period. In medulla, low proliferation activity decreased from 15 to 12 % between the 7th and 9th week. At earliest stages of gonadal development, primordial germ cells (PGC) were only rarely TP53 positive. In the 7th and 8th week, almost all PGC-s displayed TP53 positivity, while their number decreased in early fetal period. During the investigated period, caspase-3 reactivity gradually decreased in surface epithelium, while it increased in PGC and medulla of developing gonad AIFM1-positivity first appeared in surface gonad epithelium and then predominantly in PCG-s while caspase-3 characterized different cell populations within the developing gonad. AIFM1 and caspase-3 co-localized only during the migration of PCG-s. The number and distribution of Ki-67, TP53, caspase-3 and AIFM1 reacting cells changed coincidently with development end regression of the sex cords in indifferent and early fetal gonad. Our results indicate that the number of PGC might be controlled by balance of TP53 and AIFM1, leading to caspase-3 independent cell death. Other cell populations are probably eliminated by caspase-3-dependent cell death. Both pathways of cell death seem to operate during early human gonad development, while their intensity varies depending on the cell type and developmental period analysed.


Asunto(s)
Apoptosis/fisiología , Gónadas/embriología , Gónadas/metabolismo , Factor Inductor de la Apoptosis/metabolismo , Caspasa 3/metabolismo , Proliferación Celular , Femenino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Proteína p53 Supresora de Tumor/metabolismo
7.
Talanta ; 39(1): 55-62, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18965338

RESUMEN

Heterogeneous equilibria in saturated aqueous solutions of 8-hydroxyquinoline (A), 2-methyl-8-hydroxyquinoline (B) and 5-chloro-8-hydroxyquinoline (C) were investigated at constant ionic strength (1M sodium chloride), at 25.0 +/- 0.1 degrees , by the application of the following methods: the formation function method, the method of bound protons, the method of free proton sites and the solubility method. The following equilibrium constants were determined: K(s1)=[H(2)A(+)]/[H(3)O(+)], K(s2)=[HA] and K(s3)=[H(3)O(+)] [A(-)]. Their mean pK values are: -2.88, 2.42 and 12.09 for A, -3.27, 2.71 and 12.73 for B, and -0.34, 3.88 and 12.75 for C. In addition, the acidity constants of investigated 8-hydroxyquinolines were determined by pH-metric titrations. The values obtained for these constants were consistent with those calculated on the basis of corresponding equilibrium constants determined in heterogeneous systems.

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