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1.
Ultrasound Obstet Gynecol ; 57(4): 614-623, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32196791

RESUMEN

OBJECTIVE: To construct international ultrasound-based standards for fetal cerebellar growth and Sylvian fissure maturation. METHODS: Healthy, well nourished pregnant women, enrolled at < 14 weeks' gestation in the Fetal Growth Longitudinal Study (FGLS) of INTERGROWTH-21st , an international multicenter, population-based project, underwent serial three-dimensional (3D) fetal ultrasound scans every 5 ± 1 weeks until delivery in study sites located in Brazil, India, Italy, Kenya and the UK. In the present analysis, only those fetuses that underwent developmental assessment at 2 years of age were included. We measured the transcerebellar diameter and assessed Sylvian fissure maturation using two-dimensional ultrasound images extracted from available 3D fetal head volumes. The appropriateness of pooling data from the five sites was assessed using variance component analysis and standardized site differences. For each Sylvian fissure maturation score (left or right side), mean gestational age and 95% CI were calculated. Transcerebellar diameter was modeled using fractional polynomial regression, and goodness of fit was assessed. RESULTS: Of those children in the original FGLS cohort who had developmental assessment at 2 years of age, 1130 also had an available 3D ultrasound fetal head volume. The sociodemographic characteristics and pregnancy/perinatal outcomes of the study sample confirmed the health and low-risk status of the population studied. In addition, the fetuses had low morbidity and adequate growth and development at 2 years of age. In total, 3016 and 2359 individual volumes were available for transcerebellar-diameter and Sylvian-fissure analysis, respectively. Variance component analysis and standardized site differences showed that the five study populations were sufficiently similar on the basis of predefined criteria for the data to be pooled to produce international standards. A second-degree fractional polynomial provided the best fit for modeling transcerebellar diameter; we then estimated gestational-age-specific 3rd , 50th and 97th smoothed centiles. Goodness-of-fit analysis comparing empirical centiles with smoothed centile curves showed good agreement. The Sylvian fissure increased in maturation with advancing gestation, with complete overlap of the mean gestational age and 95% CIs between the sexes for each development score. No differences in Sylvian fissure maturation between the right and left hemispheres were observed. CONCLUSION: We present, for the first time, international standards for fetal cerebellar growth and Sylvian fissure maturation throughout pregnancy based on a healthy fetal population that exhibited adequate growth and development at 2 years of age. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Cerebelo/embriología , Acueducto del Mesencéfalo/embriología , Desarrollo Fetal , Gráficos de Crecimiento , Ultrasonografía Prenatal , Adulto , Brasil , Cerebelo/crecimiento & desarrollo , Acueducto del Mesencéfalo/crecimiento & desarrollo , Preescolar , Femenino , Edad Gestacional , Humanos , India , Lactante , Recién Nacido , Italia , Kenia , Estudios Longitudinales , Masculino , Embarazo , Resultado del Embarazo , Estándares de Referencia , Reino Unido
2.
Ultrasound Obstet Gynecol ; 56(3): 359-370, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32048426

RESUMEN

OBJECTIVE: To create prescriptive growth standards for five fetal brain structures, measured using ultrasound, in healthy, well-nourished women at low risk of impaired fetal growth and poor perinatal outcome, taking part in the Fetal Growth Longitudinal Study (FGLS) of the INTERGROWTH-21st Project. METHODS: This was a complementary analysis of a large, population-based, multicenter, longitudinal study. The sample analyzed was selected randomly from the overall FGLS population, ensuring an equal distribution among the eight diverse participating sites and of three-dimensional (3D) ultrasound volumes across pregnancy (range: 15-36 weeks' gestation). We measured, in planes reconstructed from 3D ultrasound volumes of the fetal head at different timepoints in pregnancy, the size of the parieto-occipital fissure (POF), Sylvian fissure (SF), anterior horn of the lateral ventricle, atrium of the posterior horn of the lateral ventricle (PV) and cisterna magna (CM). Fractional polynomials were used to construct the standards. Growth and development of the infants were assessed at 1 and 2 years of age to confirm their adequacy for constructing international standards. RESULTS: From the entire FGLS cohort of 4321 women, 451 (10.4%) were selected at random. After exclusions, 3D ultrasound volumes from 442 fetuses born without a congenital malformation were used to create the charts. The fetal brain structures of interest were identified in 90% of cases. All structures, except the PV, showed increasing size with gestational age, and the size of the POF, SF, PV and CM showed increasing variability. The 3rd , 5th , 50th , 95th and 97th smoothed centiles are presented. The 5th centiles for the POF and SF were 3.1 mm and 4.7 mm at 22 weeks' gestation and 4.6 mm and 9.9 mm at 32 weeks, respectively. The 95th centiles for the PV and CM were 8.5 mm and 7.5 mm at 22 weeks and 8.6 mm and 9.5 mm at 32 weeks, respectively. CONCLUSIONS: We have produced prescriptive size standards for fetal brain structures based on prospectively enrolled pregnancies at low risk of abnormal outcome. We recommend these as international standards for the assessment of measurements obtained using ultrasound from fetal brain structures. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Encéfalo/diagnóstico por imagen , Ultrasonografía Prenatal , Adulto , Encéfalo/crecimiento & desarrollo , Cefalometría , Femenino , Desarrollo Fetal , Edad Gestacional , Salud Global , Humanos , Estudios Longitudinales , Embarazo , Valores de Referencia
3.
BJOG ; 120 Suppl 2: 100-4, v, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23841750

RESUMEN

Turin, Italy, was one of the two European sites for the INTERGROWTH-21(st) Project. The sample for the Newborn Cross-Sectional Study (NCSS) was drawn from two obstetric hospitals that together account for 79% of the city's approximately 12,000 births per year. Women were recruited for the Fetal Growth Longitudinal Study (FGLS) from ten antenatal clinics serving the city's largest obstetric hospital, Azienda Ospedaliera OIRM-S. Anna. Special activities to encourage participation and raise awareness of the project in this population included obtaining an endorsement from the coordinator of the city's antenatal care service, and disseminating information about the project to women through posters and leaflets in antenatal clinics. One of the major challenges at this site was the low recruitment rate in the early phase of FGLS because of the high prevalence of smoking and of women >35 years old in the population. The addition of six extra recruiting clinics served to increase the pool of potentially eligible women who could be screened and led to a marked improvement in the recruitment rate.


Asunto(s)
Desarrollo Infantil , Desarrollo Fetal , Gráficos de Crecimiento , Recién Nacido/crecimiento & desarrollo , Estudios Multicéntricos como Asunto/métodos , Proyectos de Investigación , Pesos y Medidas Corporales , Protocolos Clínicos , Estudios Transversales/métodos , Femenino , Humanos , Lactante , Recien Nacido Prematuro/crecimiento & desarrollo , Italia , Estudios Longitudinales/métodos , Selección de Paciente , Embarazo , Ultrasonografía Prenatal
4.
Placenta ; 32 Suppl 2: S165-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21232791

RESUMEN

Doppler Ultrasound allows the in vivo study of feto-placental hemodynamics. Doppler flow velocity waveforms (FVW's) obtained from the umbilical arteries reflect downstream blood flow impedance, thus giving indirect evidence of vascular villous tree characteristics. Pulsatility Index, which quantifies FVW's, decreases throughout normal pregnancy, indicating decreasing impedance and is often higher in cases of fetal growth restriction (FGR). Different approaches (morphometrical, morphological, mathematical, immunohistochemical and molecular) have contributed to elucidation of which anomalies of the vascular villous tree underlie Doppler findings. 3D ultrasound may be useful in the study of feto-placental perfusion. However, the unsolved question is why developmental villous tree anomalies occur. Crucial to the success of future research is definition of the population studied based on the uniform and correct definition of FGR.


Asunto(s)
Neovascularización Fisiológica/fisiología , Placenta/irrigación sanguínea , Flujo Pulsátil/fisiología , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Retardo del Crecimiento Fetal/fisiopatología , Humanos , Placenta/diagnóstico por imagen , Placenta/fisiopatología , Embarazo , Ultrasonografía Doppler
5.
Ultrasound Obstet Gynecol ; 38(6): 681-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22411446

RESUMEN

OBJECTIVE: To assess whether a standardization exercise prior to commencing a fetal growth study involving multiple sonographers can reduce interobserver variation. METHODS: In preparation for an international study assessing fetal growth, nine experienced sonographers from eight countries participated in a standardization exercise consisting of theoretical and practical sessions. Each performed a set of seven standard fetal measurements on pregnant volunteers at 20-37 weeks' gestation, and these were repeated by the lead sonographer; all measurements were taken in a blinded fashion. After this the sonographers had hands-on practice and feedback sessions on other volunteers. This process was repeated three times. Measurement differences between sonographers and the lead sonographer, expressed as a gestational-age-specific Z-score, between the first and third scans were compared using the Wilcoxon signed ranks test, and variance was assessed using Pitman's test. Interobserver agreement was also assessed using the intraclass correlation coefficient (ICC), and all images were scored for quality in a blinded fashion. RESULTS: At baseline the level of agreement and image scoring were high. A significant reduction in the differences between sonographers and the lead sonographer were seen for fetal biometry overall (head circumference, abdominal circumference and femur length) between the first and third scans (median Z-scores, 0.46 and 0.24; P = 0.005), and a reduction in the variance was also observed (P < 0.001). The ICCs for measurement pairs for every fetal measurement showed a clear trend of increasing ICC (better agreement) with consecutive training scan sessions, although no improvement in image scores was seen. CONCLUSION: Even for experienced sonographers, a standardization exercise before starting a study of fetal biometry can improve consistency of measurements. This could be of relevance for studies assessing fetal growth in multicenter sites.


Asunto(s)
Biometría/métodos , Competencia Clínica/normas , Mejoramiento de la Calidad , Ultrasonografía Prenatal/normas , Femenino , Desarrollo Fetal , Edad Gestacional , Humanos , Masculino , Variaciones Dependientes del Observador , Embarazo , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Ultrasonografía Prenatal/métodos
6.
Ultrasound Obstet Gynecol ; 31(2): 171-6, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18254148

RESUMEN

OBJECTIVES: To investigate three-dimensional (3D) power Doppler ultrasound indices in the assessment of placental perfusion and their relationship to gestational age (GA), placental position and umbilical artery Doppler flow velocity waveform (FVW) patterns in normal and intrauterine growth-restricted (IUGR) pregnancies. METHODS: Forty-five pregnant women at 23-37 weeks' gestation were studied, of whom 30 had IUGR and 15 were controls. Nine of the IUGR group had normal umbilical FVWs (NED), nine had abnormal patterns but positive end-diastolic velocities (PED) and 12 had absent or reversed end-diastolic velocities (AED). Placental position was assessed as being posterior, anterior or lateral. 3D power Doppler indices related to placental perfusion (vascularization index (VI), vascularization flow index (VFI) and flow index (FI)) were obtained from five different sampling sites in each placenta. RESULTS: VI, VFI and FI were not significantly dependent on GA or placental position. VI and VFI were significantly lower in PED and AED cases compared with controls, while FI was reduced in the AED group only. VI and VFI showed high variability between different sampling sites within each placenta, while the variability of FI was much lower. CONCLUSIONS: 3D power Doppler sonography can provide new insights into placental pathophysiology. FI, which identifies the most severe cases of placental impairment, appears to be the most reliable index because of its low intraplacental variability. Further studies are needed to verify its accuracy when applied in clinical practice as a substitute for or an adjunct to umbilical artery Doppler studies.


Asunto(s)
Retardo del Crecimiento Fetal/diagnóstico por imagen , Placenta/irrigación sanguínea , Circulación Placentaria/fisiología , Ultrasonografía Doppler , Ultrasonografía Prenatal/métodos , Peso al Nacer , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Edad Gestacional , Humanos , Imagenología Tridimensional/métodos , Recién Nacido , Placenta/diagnóstico por imagen , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo
7.
Eur J Neurosci ; 14(3): 513-21, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11553301

RESUMEN

ErbB-4 is expressed by the periglomerular and the mitral/tufted cells of the adult mouse olfactory bulb (OB) and in the present work we tested whether this expression is regulated by the olfactory nerve input to the OB. Reversible zinc sulphate lesions of the olfactory mucosa were made in adult mice and the deafferented OB analysed by immunohistochemistry, Western blotting and semiquantitative RT-PCR. Following deafferentation, the expression of erbB-4, erbB-2 and neuregulin-1 (NRG-1) mRNAs in the OB was altered. At early stages (7-14 days) after lesion the levels of expression of olfactory marker protein (OMP), tyrosine hydroxylase (TH), erbB-4 and NRG-1 mRNAs were decreased, whilst expression of erbB-2 increased and that of NRG-2 was not significantly altered. We observed at least two distinct time courses for these expression changes. The lowest amounts of mRNA for erbB-4 and NRG-1 were observed at day 7 after lesion, whilst mRNAs for TH and OMP were lowest at day 14. At day 28 after the lesion, when olfactory receptor neuron axons had reinnervated the olfactory bulb, the expression levels of OMP, TH, erbB-2, erbB-4 and NRG-1 were identical to control values. These results indicate that the expression of erbB-4 mRNA and protein in periglomerular and mitral cells is controlled by peripheral olfactory innervation. The tight correlation in NRG-1 and erbB-4 expression levels also suggests a possible functional link that deserves further exploration.


Asunto(s)
Receptores ErbB/biosíntesis , Neurregulinas/biosíntesis , Bulbo Olfatorio/metabolismo , Nervios Periféricos/fisiología , Animales , Astringentes , Western Blotting , Desnervación , Receptores ErbB/genética , Femenino , Inmunohistoquímica , Ratones , Degeneración Nerviosa/inducido químicamente , Neurregulinas/genética , Mucosa Olfatoria/fisiología , Nervio Olfatorio/fisiología , Pruebas de Precipitina , Receptor ErbB-4 , Transcripción Genética , Sulfato de Zinc
8.
Cell Mol Biol (Noisy-le-grand) ; 45(3): 293-301, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10386786

RESUMEN

Previously, we have shown that erbB-3 expression is restricted to the ensheathing cells of the olfactory nerve layer, while erbB-4 is found in the periglomerular and mitral/tufted cells of the olfactory bulb and in cells coming out from the rostral migratory stream of the subependymal layer. In the present work, we have treated adult mice with zinc sulfate intranasal irrigation and analyzed erbB-3 and erbB-4 expression in the deafferented olfactory bulb. Following treatment, olfactory axons undergo degeneration, as indicated by the loss of OMP expression in the deafferented olfactory bulb. The thickness of the olfactory nerve layer is reduced, but the specific intensity of erbB-3 labeling in the remaining olfactory nerve layer is increased with respect to control. Interestingly, following deafferentation, erbB-4 immunoreactivity decreases specifically in cell types that normally make synaptic contacts with primary olfactory neurons in the glomeruli, i.e. periglomerular and mitral/tufted cells. Partial lesion of the olfactory epithelium allows regenerative axon growth of olfactory neurons to the olfactory bulb. Following olfactory axon regeneration, erbB-3 and erbB-4 immunoreactivity in the olfactory bulb is similar to control. Thus, like tyrosine hydroxylase, the down regulation of erbB-4 expression in the periglomerular cells is reversible.


Asunto(s)
Receptores ErbB/metabolismo , Bulbo Olfatorio/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Administración Intranasal , Animales , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Femenino , Inmunohistoquímica , Ratones , Ratones Endogámicos , Degeneración Nerviosa/inducido químicamente , Proteínas del Tejido Nervioso/metabolismo , Neuronas Aferentes/efectos de los fármacos , Bulbo Olfatorio/efectos de los fármacos , Proteína Marcadora Olfativa , Nervio Olfatorio/efectos de los fármacos , Nervio Olfatorio/metabolismo , Receptor ErbB-3 , Receptor ErbB-4 , Sulfato de Zinc
9.
Leukemia ; 12(10): 1561-4, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9766500

RESUMEN

Acute leukemias of the t(4;11) (MLL-AF4 fusion gene) type frequently have high white blood counts and extramedullary disease in multiple organs. In the present study we evaluated the hypotheses that this extensive disease is the result of extramedullary survival of leukemia cells due to resistance to stress-induced cell death. Leukemias with t(4;11)(MLL-AF4) were found to be resistant to the cell death that results from serum deprivation in vitro when compared with B lineage acute leukemias without t(4;11)(MLL-AF4). Cells with t(4;11)(MLL-AF4) did not have increased doubling time or increased numbers of cells in cycle. These results suggest that the alteration in cellular homeostasis in these leukemias is due to abnormalities of cellular destruction rather than cellular proliferation when compared to other leukemias. Our results are consistent with the hypothesis that death of non-t(4;11) leukemias occurs in the microenvironment outside of the bone marrow as a result of deficient cellular and humoral growth factors. Resistance to death signals in t(4;11) leukemias results in extensive accumulation of leukemia cells in extramedullary sites and likely contributes to the poor prognosis of these leukemias.


Asunto(s)
Fusión Artificial Génica , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 4 , Proteínas de Unión al ADN/genética , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proto-Oncogenes , Factores de Transcripción , Translocación Genética , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Ciclo Celular , División Celular , Supervivencia Celular , Niño , N-Metiltransferasa de Histona-Lisina , Humanos , Cinética , Proteína de la Leucemia Mieloide-Linfoide , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Factores de Elongación Transcripcional , Células Tumorales Cultivadas , Dedos de Zinc
10.
Ann N Y Acad Sci ; 855: 255-9, 1998 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-9929617

RESUMEN

The interplay between neuregulins and the ErbB receptor family has a pivotal role in the development of several tissues, including the nervous system, and is maintained in the adult olfactory system where extensive plasticity and neurogenesis are retained. In the present work we show the immunohistochemical localization of ErbB-3 and ErbB-4 in the olfactory system of adult normal and lesioned mice. The expression of ErbB-3 is demonstrated to be restricted to the ensheathing cells of the olfactory nerve and to a few substentacular cells of the olfactory epithelium (OE). ErbB-3 staining circumvents the glomeruli but is never observed inside them or elsewhere in the adult olfactory bulb. Conversely, ErbB-4 immunoreactivity is found in all the periglomerular and mitral/tufted cells of the olfactory bulb (OB) and to a minor extent in the olfactory neurons and basal cells of the OE. Interestingly enough, cells coming out from the rostral migratory stream of the subependymal layer (SEL), as well as isolated cells in the granule cell layer, possibly migrating cells, strongly stained for ErbB-4 expression. Lesions of the olfactory epithelium have been performed by unilateral intranasal irrigation with ZnSO4 and 3 weeks after the irrigation, the olfactory bulbs were analyzed for olfactory marker protein (OMP), tyrosine hydroxylase (TH), ErbB-3 and ErbB-4 expression. In the deafferented OB, the drastic loss of immunoreactivity for OMP was accompanied by a strong reduction of ErbB-3 expression. Most of the deafferented dopaminergic interneurons switched off TH expression. In the deafferented periglomerular and mitral/tufted cells ErbB-4 expression was turned off and down, respectively. No differences were noted at the granular cell layer level in the deafferented OB with respect to control. Taken together our results suggest that, in normal conditions, neuregulins are involved in the survival of the ensheathing cells of the olfactory nerve through ErbB-3 activation and in the functional activity of postsynaptic neurons through ErbB-4 activation.


Asunto(s)
Receptores ErbB/biosíntesis , Vías Olfatorias/metabolismo , Proteínas Proto-Oncogénicas/biosíntesis , Animales , Femenino , Regulación de la Expresión Génica , Inmunohistoquímica , Ratones , Receptor ErbB-3 , Receptor ErbB-4
11.
Panminerva Med ; 36(1): 48-9, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8090544

RESUMEN

The results are reported of experimental research into the hypophyseal endorphins in 42 drug addicts killed by heroin overdose. All samples were found to contain endorphins in widely varied amounts: 21-239 ng/g, mean 81.8 +/- 45.8 ng/g.


Asunto(s)
Dependencia de Heroína/metabolismo , Heroína/envenenamiento , Hipófisis/química , betaendorfina/análisis , Adolescente , Adulto , Sobredosis de Droga , Femenino , Humanos , Masculino
12.
J Pediatr Orthop ; 4(6): 749-51, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6511904

RESUMEN

Acute plastic bowing injuries in children characteristically heal with little periosteal callus and exhibit a limited potential to remodel. A case of plastic bowing of the femur in a neonate is reported in which follow-up radiographs demonstrated periosteal new bone formation and rapid remodeling of the deformity. This report suggests that plastic bowing injuries in the neonate show a greater remodeling potential than similar lesions in older children.


Asunto(s)
Traumatismos del Nacimiento/diagnóstico por imagen , Fémur/lesiones , Desarrollo Óseo , Resorción Ósea , Fémur/diagnóstico por imagen , Fémur/fisiología , Humanos , Recién Nacido , Radiografía
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