49 research outputs found
Errors in chromosome segregation during oogenesis and early embryogenesis
Errors in chromosome segregation occurring during human oogenesis and early embryogenesis are very common. Meiotic chromosome development during oogenesis is subdivided into three distinct phases. The crucial events, including meiotic chromosome pairing and recombination, take place from around 11 weeks until birth. Oogenesis is then arrested until ovulation, when the first meiotic division takes place, with the second meiotic division not completed until after fertilization. It is generally accepted that most aneuploid fetal conditions, such as trisomy 21 Down syndrome, are due to maternal chromosome segregation errors. The underlying reasons are not yet fully understood. It is also clear that superimposed on the maternal meiotic chromosome segregation errors, there are a large number of mitotic errors taking place post-zygotically during the first few cell divisions in the embryo. In this chapter, we summarise current knowledge of errors in chromosome segregation during oogenesis and early embryogenesis, with special reference to the clinical implications for successful assisted reproduction
An integrated infant and young child feeding and small-quantity lipid-based nutrient supplementation programme in the Democratic Republic of Congo is associated with improvements in breastfeeding and handwashing behaviours but not dietary diversity.
Integrating small-quantity lipid-based nutrient supplements (SQ-LNS) into infant and young child feeding (IYCF) programmes can increase consumption of essential nutrients among children in vulnerable populations; however, few studies have assessed the impact of integrated IYCF-SQ-LNS programmes on IYCF practices. A 2-year, enhanced IYCF intervention targeting pregnant women and infants (0-12 months) was implemented in a health zone in the Democratic Republic of Congo (DRC). The enhanced IYCF intervention included community- and facility-based counselling for mothers on handwashing, SQ-LNS, and IYCF practices, plus monthly SQ-LNS distributions for children 6-12 months; a control zone received the national IYCF programme (facility-based IYCF counselling with no SQ-LNS distributions). Cross-sectional preintervention and postintervention surveys (n = 650 and 638 in intervention and control areas at baseline; n = 654 and 653 in each area at endline, respectively) were conducted in mothers of children 6-18 months representative of both zones. Difference in differences (DiD) analyses used mixed linear regression models. There were significantly greater increases in the proportion of mothers in the intervention (vs. control) zone who reported: initiating breastfeeding within 1 hr of birth (Adj. DiD [95% CI]: +56.4% [49.3, 63.4], P < 0.001), waiting until 6 months to introduce water (+66.9% [60.6, 73.2], P < 0.001) and complementary foods (+56.4% [49.3, 63.4], P < 0.001), feeding the minimum meal frequency the previous day (+9.2% [2.7, 15.7], P = 0.005); feeding the child in a separate bowl (+9.7% [2.2, 17.2], P = 0.01); awareness of anaemia (+16.9% [10.4, 23.3], P < 0.001); owning soap (+14.9% [8.3, 21.5], P < 0.001); and washing hands after defecating and before cooking and feeding the child the previous day (+10.5% [5.8, 15.2], +12.5% [9.3, 15.6] and +15.0% [11.2, 18.8], respectively, P < 0.001 for all). The enhanced IYCF intervention in the DRC was associated with an improvement in several important IYCF practices but was not associated with a change in dietary diversity (minimum dietary diversity and minimum acceptable diet remained below 10% in both zones without significant differences between zones). The provision of fortified complementary foods, such as SQ-LNS, may be an important source of micronutrients and macronutrients for young children in areas with high rates of poverty and limited access to diverse foods. Future research should verify the potential of integrated IYCF-SQ-LNS to improve IYCF practices, and ultimately children's nutritional status
Comprehensive analysis of karyotypic mosaicism between trophectoderm and inner cell mass
Aneuploidy has been well-documented in blastocyst embryos, but prior studies have been limited in scale and/or lack mechanistic data. We previously reported preclinical validation of microarray 24-chromosome preimplantation genetic screening in a 24-h protocol. The method diagnoses chromosome copy number, structural chromosome aberrations, parental source of aneuploidy and distinguishes certain meiotic from mitotic errors. In this study, our objective was to examine aneuploidy in human blastocysts and determine correspondence of karyotypes between trophectoderm (TE) and inner cell mass (ICM). We disaggregated 51 blastocysts from 17 couples into ICM and one or two TE fractions. The average maternal age was 31. Next, we ran 24-chromosome microarray molecular karyotyping on all of the samples, and then performed a retrospective analysis of the data. The average per-chromosome confidence was 99.95%. Approximately 80% of blastocysts were euploid. The majority of aneuploid embryos were simple aneuploid, i.e. one or two whole-chromosome imbalances. Structural chromosome aberrations, which are common in cleavage stage embryos, occurred in only three blastocysts (5.8%). All TE biopsies derived from the same embryos were concordant. Forty-nine of 51 (96.1%) ICM samples were concordant with TE biopsies derived from the same embryos. Discordance between TE and ICM occurred only in the two embryos with structural chromosome aberration. We conclude that TE karyotype is an excellent predictor of ICM karyotype. Discordance between TE and ICM occurred only in embryos with structural chromosome aberrations
Combined infant and young child feeding with small-quantity lipid-based nutrient supplementation is associated with a reduction in anemia but no changes in anthropometric status of young children from Katanga Province of the Democratic Republic of Congo: a quasi-experimental effectiveness study.
BACKGROUND: Small-quantity lipid-based nutrient supplements (SQ-LNS) are efficacious in controlled settings; data are scarce on the effectiveness utilizing health care delivery platforms. OBJECTIVE: We evaluated the impact of an infant young child feeding (IYCF)-SQ-LNS intervention on anemia and growth in children aged 6-18 mo in the Democratic Republic of Congo following a quasi-experimental effectiveness design. METHODS: An intervention health zone (HZ) received enhanced IYCF including improved counseling on IYCF during pregnancy until 12 mo after birth and daily use of SQ-LNS for infants 6-12 mo; the control HZ received the standard IYCF package. We analyzed data from 2995 children, collected in repeated cross-sectional surveys. We used adjusted difference-in-difference analyses to calculate changes in anemia, iron and vitamin A deficiencies, stunting, wasting, and underweight. RESULTS: Of mothers, 70.5% received SQ-LNS at least once in the intervention HZ, with 99.6% of their children consuming SQ-LNS at least once. The mean number of batches of SQ-LNS (28 sachets per batch, 6 batches total) received was 2.3 ± 0.8 (i.e., 64.4 ± 22.4 d of SQ-LNS). The enhanced program was associated with an 11.0% point (95% CI: -18.1, -3.8; P < 0.01) adjusted relative reduction in anemia prevalence and a mean +0.26-g/dL (95% CI: 0.04, 0.48; P = 0.02) increase in hemoglobin but no effect on anthropometry or iron or vitamin A deficiencies. At endline in the intervention HZ, children aged 8-13 mo who received ≥3 monthly SQ-LNS batch distributions had higher anthropometry z scores [length-for-age z score (LAZ): +0.40, P = 0.04; weight-for-age z score (WAZ): +0.37, P = 0.04] and hemoglobin (+0.65 g/dL, P = 0.007) and a lower adjusted prevalence difference of stunting (-16.7%, P = 0.03) compared with those who received none. CONCLUSIONS: The enhanced IYCF-SQ-LNS intervention using the existing health care delivery platform was associated with a reduction in prevalence of anemia and improvement in mean hemoglobin. At endline among the subpopulation receiving ≥3 mo of SQ-LNS, their LAZ, WAZ, and hemoglobin improved. Future research could explore contextual tools to maximize coverage and intake adherence in programs using SQ-LNS
Enteritis secundaria a nivolumab, una causa creciente de diarrea
La inmunoterapia es una herramienta cada vez más utilizada en el campo de la oncología. Conviene conocerla debido a sus crecientes usos, entre los que se incluye el tratamiento de tumores del aparato digestivo (hepatocarcinoma1, adenocarcinoma colorrectal con alta inestabilidad en microsatelites2) así como por las reacciones adversas que con elevada frecuencia afectan al tubo digestivo.
Presentamos el caso de un varón de 74 años, con antecedentes personales de enfermedad pulmonar obstructiva crónica (EPOC) y melanoma con metástasis pulmonares. Debido a estas patologías tomaba de manera habitual inhaladores de salbutamol y había estado en tratamiento con nivolumab, suspendido hacía cuatro meses tras conseguir una respuesta radiológica completa de las metástasis pulmonares.
El paciente refería cuadro diarreico de un mes de evolución, consistente en tres a cuadro deposiciones (Bristol 5-6) sin productos patológicos, que afectaban el descanso nocturno, asociaban molestias centroabdominales intermitentes y pérdida de peso de unos 3-4 kg. No había ingerido alimentos crudos, antibióticos o nuevas medicaciones. Tampoco había convivientes con la misma sintomatología ni había realizado viajes al extranjero. Negaba cualquier otra sintomatología y antecedentes familiares de interés. La exploración física era anodina a excepción de unas ligeras molestias a la palpación profunda en mesogastrio..
Aproximación al manejo de la disección del tronco celíaco
El dolor abdominal constituye uno de los motivos de consulta más frecuentes en los servicios de Urgencias y de Aparato Digestivo. Además, el diagnóstico diferencial supone un importante reto, dado el amplio abanico de entidades clínicas que pueden provocarlo, algunas de ellas con un pronóstico desfavorable. En este sentido, en algunas cohortes no se ha llegado a un diagnóstico específico en más de un 30% de los casos1, 2.
Se presenta el caso de un varón de 40 años, fumador activo desde hace más de 20 años, sin otros antecedentes personales ni familiares de interés, excepto traumatismo cerrado abdominal hace cuatro años, que no seguía tratamiento farmacológico habitual. Presentaba dolor abdominal epigástrico continuo e irradiado hacia ambos hipocondrios, de ocho horas de evolución. No asociaba ictericia mucocutánea ni coluria o acolia, tampoco náuseas ni vómitos ni alteraciones en el ritmo y características de las deposiciones. No presentaba fiebre, síndrome constitucional ni otra sintomatología asociada.
A la exploración física destacaba dolor a la palpación de epigastrio, sin signos de irritación peritoneal, con peristaltismo y pulsos distales conservados. Asimismo, no presentaba signos de colagenopatía. Para una primera aproximación diagnóstica se realizó analítica de sangre, destacando como únicos hallazgos ligera alteración del perfil hepático (AST 66 U/L, ALT 58 U/L, GGT 106 U/L, FA 76 U/L) con amilasemia, ..
Retablos-tabernáculo de la Baja Edad Media en la Corona de Castilla. Ficha 7/38
Producción CientíficaCastildelgado (Burgos), hermitage of Nuestra Señora la Real del Campo (Castildelgado [Burgos], church of San Pedro y San Esteban – the titular image –, and Barcelona, Museu Frederic Marès, inv. no 814 – the remaining elements –): titular image, baldachin and all four panels. DEDICATEE: Virgin and Child (Nuestra Señora la Real del Campo). OBVERSE: scenes of the infancy of Christ and of the death and glorification of the Virgin (reliefs). REVERSE: plain black (overpainted). DATE: fourteenth century. - Ficha incluida en el anexo "Updated list of Castilian tabernacle-altarpieces" publicado en: Fernando Gutiérrez Baños, Justin Kroesen, Elisabeth Andersen (eds.). The Saint enshrined: European tabernacle - altarpieces, c. 1150–1400. Barcelona: Instituto de Estudios Medievales, 2020.Departamento de Historia del ArteMinisterio de Economía, Industria y Competitividad, AEI, FEDER, UE (HAR2017-82949-P
Raman laser fiber optic strategy for non-destructive pigment analysis
In this work, the strategy, performances and applications of a Raman spectroscopy system with both optical fibre technology and two lasers (red and green) are presented. With this system, we have investigated certain yellow pigment from Italian paintings of the XVII century whose composition is not yet exactly known. The comparison of its Raman spectrum with the spectra of two yellow patterns that we have produced demonstrates the triple oxide composition (Pb, Sn and Sb) of this Italian pigment. This result is in good agreement with the previous works obtained by other authors with scanning electron microscopy-energy dispersive X-rays (SEM-EDX). The paintings we have analysed here are “Lot and his daughters”, by G.B. Langetti, and “Entrance of Christ in Jerusalem”, by Luca Giordano.Peer ReviewedPostprint (published version