17 research outputs found
Atypical hepatic vacuolated cell lesion in the white perch \u3cem\u3eMorone americana\u3c/em\u3e
This report details histopathological findings of atypical vacuolated hepatocytes in the white perch Morone americana. Vacuolated cell lesions have been reported from a number of species in association with degraded habitats, often in the presence of hepatic neoplasms. Extensive atypical vacuolated cell lesions assuming characteristic acinar or ductular configurations have been reported previously only from the winter flounder Pseudopleuronectes americanus. Light microscopic findings, utilizing a variety of histochemical stains, suggest the identical nature of this lesion to that of winter flounder. The discovery of this lesion in a free-swimming species, feeding throughout the water column, is in direct contrast to that of the bottom dwelling pleuronectid, feeding from and constantly in contact with potentially contaminated sediments. While the winter flounder has become the sentinel fish species for pollution monitoring on the northeast coast, increased surveillance of other species may prove atypical vacuolated cell lesions represent a common mechanism of chronic cellular injury in relation to impacted environments
Hypoxia Impairs Primordial Germ Cell Migration in Zebrafish (Danio rerio) Embryos
Background: As a global environmental concern, hypoxia is known to be associated with many biological and physiological impairments in aquatic ecosystems. Previous studies have mainly focused on the effect of hypoxia in adult animals. However, the effect of hypoxia and the underlying mechanism of how hypoxia affects embryonic development of aquatic animals remain unclear. Methodology/Principal Findings: In the current study, the effect of hypoxia on primordial germ cell (PGC) migration in zebrafish embryos was investigated. Hypoxic embryos showed PGC migration defect as indicated by the presence of mis-migrated ectopic PGCs. Insulin-like growth factor (IGF) signaling is required for embryonic germ line development. Using real-time PCR, we found that the mRNA expression levels of insulin-like growth factor binding protein (IGFBP-1), an inhibitor of IGF bioactivity, were significantly increased in hypoxic embryos. Morpholino knockdown of IGFBP-1 rescued the PGC migration defect phenotype in hypoxic embryos, suggesting the role of IGFBP-1 in inducing PGC mis-migration. Conclusions/Significance: This study provides novel evidence that hypoxia disrupts PGC migration during embryonic development in fish. IGF signaling is shown to be one of the possible mechanisms for the causal link between hypoxia and PGC migration. We propose that hypoxia causes PGC migration defect by inhibiting IGF signaling through the induction of IGFBP-1
The intergenerational association between parents' problem gambling and impulsivity-hyperactivity/inattention behaviors in children
Despite the well-established association between problem gambling and ADHD core categories of impulsivity-hyperactivity and inattention, the link between parentsâ problem gambling and impulsivity-hyperactivity/inattention (IH/I) behaviors in children has not been investigated. This study investigated the association between parentsâ problem gambling and childrenâs IH/I behaviors while controlling for potential confounding variables. A population-based prospective cohort followed-up from kindergarten to age 30, the Quebec Longitudinal Study of Kindergarten Children (QLSKC), provided data over three generations. Among 1358 participants at age 30, parents with a child aged 1 year or older (N=468; Mean age=4.65 years; SD=2.70) were selected. Generalized Linear Models included measures of grandparentsâ and parentsâ problem gambling, parentsâ IH/I behaviors in childhood, and a host of risk factors and comorbidities to predict IH/I in children. Intergenerational bivariate associations were observed between grandparentsâ problem gambling, parentsâ IH/I in childhood and problem gambling at age 30, and between parentsâ IH/I, problem gambling, and childrenâs IH/I behaviors. Parentsâ problem gambling predicted childrenâs IH/I behaviors above and beyond the effects of covariates such as family and socioeconomic characteristics, alcohol and drug use, depression symptoms and parentsâ gambling involvement. Parentsâ IH/I behaviors in childhood also predicted childrenâs IH/I and had a moderating, enhancing effect on parentsâ problem gambling association with their offspringâs IH/I behaviors. Problem gambling is a characteristic of parentsâ mental health that is distinctively associated with childrenâs IH/I behaviors, above and beyond parentsâ own history of IH/I and of typically related addictive, psychopathological or socioeconomic risk factors and comorbidities
Study of doubly strange systems using stored antiprotons
Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PâŸANDA experiment at FAIR. For the first time, high resolution Îł-spectroscopy of doubly strange ÎÎ-hypernuclei will be performed, thus complementing measurements of ground state decays of ÎÎ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Îâ-atoms will be feasible and even the production of Ωâ-atoms will be within reach. The latter might open the door to the |S|=3 world in strangeness nuclear physics, by the study of the hadronic Ωâ-nucleus interaction. For the first time it will be possible to study the behavior of ÎâŸ+ in nuclear systems under well controlled conditions
Extinction risk of Mesoamerican crop wild relatives
Ensuring food security is one of the world's most critical issues as agricultural systems are already being impacted by global change. Crop wild relatives (CWR)âwild plants related to cropsâpossess genetic variability that can help adapt agriculture to a changing environment and sustainably increase crop yields to meet the food security challenge.
Here we report the results of an extinction risk assessment of 224 wild relatives of some of the world's most important crops (i.e. chilli pepper, maize, common bean, avocado, cotton, potato, squash, vanilla and husk tomato) in Mesoamericaâan area of global significance as a centre of crop origin, domestication and of high CWR diversity.
We show that 35% of the selected CWR taxa are threatened with extinction according to The International Union for Conservation of Nature (IUCN) Red List demonstrates that these valuable genetic resources are under high anthropogenic threat. The dominant threat processes are land use change for agriculture and farming, invasive and other problematic species (e.g. pests, genetically modified organisms) and use of biological resources, including overcollection and logging. The most significant drivers of extinction relate to smallholder agricultureâgiven its high incidence and ongoing shifts from traditional agriculture to modern practices (e.g. use of herbicides)âsmallholder ranching and housing and urban development and introduced genetic material.
There is an urgent need to increase knowledge and research around different aspects of CWR. Policies that support in situ and ex situ conservation of CWR and promote sustainable agriculture are pivotal to secure these resources for the benefit of current and future generations
An in vitro assay to measure phagocytosis in striped bass hybrids (Morone saxatilis Ă Morone chrysops)
An in vitro phagocytosis assay was developed for hybrid striped bass (Morone saxatilisĂMorone chrysops), using cells collected from the peritoneal cavity of this fish. The findings indicated that: (1) 10 days following a single intraperitoneal injection (1ml) of Freund\u27s incomplete adjuvant (FIA) was an appropriate time for collecting suitable working concentrations (5·3± 4·0Ă107cells ml-1) of peritoneal phagocytes (83·7±1·5% macrophages) from these hybrids held at 23°C; (2) these cells phagocytosed latex beads (polystyrene microspheres 3·12ÎŒm in diameter) after 30min of in vitro incubation at room temperature (25±1°C). The phagocytic ability and phagocytic capacity in a washed adherent layer exposure system were 67·2±2·76% and 4·14±0·35 beads phagocyte-1, respectively. These results strongly suggest that a simple methodology, including baseline data serving as guidelines, is now available for conducting in vitro phagocytosis assays in this hybrid © 2000 Academic Press
Increased prefrontal activation in adolescents born prematurely at high risk during a reading task
The influence of hemodilution on outcome after hypothermic cardiopulmonary bypass: results of a randomized trial in infants
Child Psychiatry Hum Dev
This cross-sectional study examined the moderating role of support from three key figures (mothers, teachers, friends) in the association between peer victimization and parasomnias in childhood. The sample consisted of 1150 children aged 8 years who attended elementary school. Controlling for potential confounders, hierarchical multiple regressions revealed that peer victimization was associated with a higher level of parasomnias, equally for both girls and boys. However, for girls, the predictive association of peer victimization with parasomnias was moderated by the level of support in relationships with either their parents, their teachers, or their friends. The findings suggest that somatic symptoms such as sleep problems may be a first indicator that a child is being bullied. Because parents, teachers as well as friends can play a key role in preventing the development of parasomnias, it may be useful to help bullied children develop strong bonds within at least one of these relationships