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

Rapid mapping of chromosomal breakpoints: from blood to BAC in 20 days

Structural chromosome aberrations and associated segmental or chromosomal aneusomies are major causes of reproductive failure in humans. Despite the fact that carriers of reciprocal balanced translocation often have no other clinical symptoms or disease, impaired chromosome homologue pairing in meiosis and karyokinesis errors lead to over-representation of translocations carriers in the infertile population and in recurrent pregnancy loss patients. At present, clinicians have no means to select healthy germ cells or balanced zygotes in vivo, but in vitro fertilization (IVF) followed by preimplantation genetic diagnosis (PGD) offers translocation carriers a chance to select balanced or normal embryos for transfer. Although a combination of telomeric and centromeric probes can differentiate embryos that are unbalanced from normal or unbalanced ones, a seemingly random position of breakpoints in these IVF-patients poses a serious obstacle to differentiating between normal and balanced embryos, which for most translocation couples, is desirable. Using a carrier with reciprocal translocation t(4;13) as an example, we describe our state-of-the-art approach to the preparation of patient-specific DNA probes that span or 'extent' the breakpoints. With the techniques and resources described here, most breakpoints can be accurately mapped in a matter of days using carrier lymphocytes, and a few extra days are allowed for PGD-probe optimization. The optimized probes will then be suitable for interphase cell analysis, a prerequisite for PGD since blastomeres are biopsied from normally growing day 3 – embryos regardless of their position in the mitotic cell cycle. Furthermore, routine application of these rapid methods should make PGD even more affordable for translocation carriers enrolled in IVF programs

A review of assessment methods for river hydromorphology

The work leading to this paper has received funding for the EU’s FP7 under Grant Agreement No. 282656 (REFORM

Grape berry responses to sequential flooding and heatwave events: a physiological, transcriptional, and metabolic overview

Grapevine cultivation, such as the whole horticulture, is currently challenged by several factors, among which the extreme weather events occurring under the climate change scenario are the most relevant. Within this context, the present study aims at characterizing at the berry level the physiological response of Vitis vinifera cv. Sauvignon Blanc to sequential stresses simulated under a semi-controlled environment: flooding at bud-break followed by multiple summer stress (drought plus heatwave) occurring at pre-vèraison. Transcriptomic and metabolomic assessments were performed through RNASeq and NMR, respectively. A comprehensive hormone profiling was also carried out. Results pointed out a different response to the heatwave in the two situations. Flooding caused a developmental advance, determining a different physiological background in the berry, thus affecting its response to the summer stress at both transcriptional levels, with the upregulation of genes involved in oxidative stress responses, and metabolic level, with the increase in osmoprotectants, such as proline and other amino acids. In conclusion, sequential stress, including a flooding event at bud-break followed by a summer heatwave, may impact phenological development and berry ripening, with possible consequences on berry and wine quality. A berry physiological model is presented that may support the development of sustainable vineyard management solutions to improve the water use efficiency and adaptation capacity of actual viticultural systems to future scenario

Intermittent rivers and ephemeral streams: what water managers need to know

Peer reviewe

Habitat quality affects the condition of Luciobarbus sclateri in the Guadiamar River (SW Iberian Peninsula): Effects of disturbances by the toxic spill of the Aznalcóllar mine

This study analyzes the somatic condition of southern Iberian barbel Luciobarbus sclateri (Günther, 1868) in the Guadiamar River (SW Iberian Peninsula). This river was seriously affected by a toxic spill of about 4 million cubic meters of acidic water and 2 million cubic meters of mud rich in heavy metals. Once the spill removal works concluded, sites affected and unaffected by the accident were sampled to study its effects on the fish fauna. The ecological variables registered were related to water quality, physical state of reaches, ecological quality, resources exploited by fish, and potential intra-specific interactions. From an initial 15 ecological variables, seasonal water flow and pH explained most of the variation in barbel condition. This study shows that the Guadiamar River, 56 months after the accident, is still undergoing a recovery process where, beyond ecological variables, proximity to the affected area is the most influential factor for fish condition. © 2012 Springer Science+Business Media B.V

Duration of viremia and fecal shedding of the virus in hepatitis A infected children

La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en suero y heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 pacientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepática fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyen al control y la toma de decisiones eficientes en políticas de Salud Pública.Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liver failure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentina and it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologic surveillance may contribute to efficient control and lead to rational decisions in public health policies.Fil: Munné, María Silvina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Cañero Velasco, María C. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Moreiro, Rita. Hospital Nacional de Pediatría J. P. Garrahan. Laboratorio; Argentina.Fil: Vladimirsky, Sara. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Otegui, Lucio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Castro, Raúl. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Brajterman, Leonardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Soto, Sonia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Mutti, Jorge. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Nucifora, Silvia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Lara, Elena. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Sosa, Anibal. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Godoy, Patricia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Ciocca, Mirta. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Cuarterolo, Miriam. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Quarleri, Jorge F. Facultad de Medicina. Centro Nacional de Referencia para el SIDA; Argentina.Fil: González, Jorge E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina

Duration of viremia and fecal shedding of the virus in hepatitis A infected children

La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en suero y heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 pacientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepática fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyen al control y la toma de decisiones eficientes en políticas de Salud Pública.Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liver failure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentina and it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologic surveillance may contribute to efficient control and lead to rational decisions in public health policies.Fil: Munné, María Silvina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Cañero Velasco, María C. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Moreiro, Rita. Hospital Nacional de Pediatría J. P. Garrahan. Laboratorio; Argentina.Fil: Vladimirsky, Sara. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Otegui, Lucio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Castro, Raúl. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Brajterman, Leonardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Soto, Sonia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Mutti, Jorge. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Nucifora, Silvia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Lara, Elena. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Sosa, Anibal. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Godoy, Patricia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Ciocca, Mirta. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Cuarterolo, Miriam. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Quarleri, Jorge F. Facultad de Medicina. Centro Nacional de Referencia para el SIDA; Argentina.Fil: González, Jorge E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina