Southern flounder (Paralichthys lethostigma) exhibit environmental sex determination (ESD), where environmental factors can influence phenotypic sex during early juvenile development but only in the ...presumed XX female genotype. Warm and cold temperatures masculinize fish with mid-range conditions producing at most 50% females. Due to sexually dimorphic growth, southern flounder fisheries are dependent upon larger females. Wild populations could be at risk of masculinization from ESD due to globally increasing water temperatures. We evaluated the effects of habitat and temperature on wild populations of juvenile southern flounder in North Carolina, USA. While northern habitats averaged temperatures near 23 °C and produced the greatest proportion of females, more southerly habitats exhibited warmer temperatures (>27 °C) and consistently produced male-biased sex ratios (up to 94% male). Rearing flounder in the laboratory under temperature regimes mimicking those of natural habitats recapitulated sex ratio differences observed across the wild populations, providing strong evidence that temperature is a key factor influencing sex ratios in nursery habitats. These studies provide evidence of habitat conditions interacting with ESD to affect a key demographic parameter in an economically important fishery. The temperature ranges that yield male-biased sex ratios are within the scope of predicted increases in ocean temperature under climate change.
Studying neurons from an energy efficiency perspective has produced results in the research literature. This paper presents a method that enables computation of low energy input current stimuli that ...are able to drive a reduced Hodgkin–Huxley neuron model to approximate a prescribed time-varying reference membrane voltage. An optimal control technique is used to discover an input current that optimally minimizes a user selected balance between the square of the input stimulus current (input current ‘energy’) and the difference between the reference voltage and the membrane voltage (tracking error) over a stimulation period. Selecting reference signals to be membrane voltages produced by the neuron model in response to common types of input currents
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Nutritional programming is the idea that early nutrient contributions can influence organismal structure or function and is documented in a variety of vertebrates, yet studies in fish are largely ...lacking. Tilapia are an important foodfish, with global production having increased rapidly since the 1990s. They exhibit high disease-resistance and grow well on formulated feeds which makes them an ideal aquaculture species, however incorporating high quality proteins into feeds can be costly. As feed constitutes 50-70% of total production costs in aquaculture, reducing protein content could curb these costs and increase revenue. Thus, we examined the effects of feeding Nile tilapia (O. niloticus) fry a restricted protein diet for the first 7-21 days on growth, gut microbial flora, and the intestinal transcriptome. Fish were fed either a 25% restricted or 48% control crude protein starter (ST) diet for up to 21 days and then switched to a 25% or 38% control crude protein growout (GO) diet. Fish fed a 25% ST diet for 14 days followed by a 38% GO diet had significantly higher lengths and weights and better feed efficiency than fish fed the control 48% ST and 38% GO diet after 56 days of culture. Growth of fry on the 25% ST, 7-day/38% GO and the 25% ST,7-day/25% GO diets did not differ from the those fed the control protein diets, while fish fed the 25% ST diet for 21 days had significantly lower growth and survival rates. We observed no significant differences in either alpha or beta diversity of the gut microbial flora between diets, however species richness (Shannon Index) was higher in fry fed the 25% protein ST diet regardless of the GO diet. Similarly, fish fed the 25% ST diet for 14 days followed by the 38% GO diet had minimal changes to the intestinal transcriptome relative to fish fed the control 48% ST and 38% GO diet. However, those fed 25% ST and GO diets for the entire 56 days exhibited substantial differences in the gut transcriptome from other groups showing gene expression profiles characteristic of detrimental changes to gut physiology, protein metabolism and immune function. Results suggest protein restriction for up to 14 days early in development leads to enhanced growth and feed efficiency with minimal effects on gut microbes or intestinal function. Protein restriction beyond this period appears detrimental to fish growth and health as underscored by expression of disease related genes and higher mortality rates.
Highlights • In schizophrenia, elevated Candida yeast antibody levels were lowered by probiotics. • Probiotics compared to placebo also relieved yeast-related bowel discomfort over time. • Candida ...albicans seropositivity was associated with worse psychiatric symptoms.
Abstract Strategies combatting cognitive decline among the growing aging population are vital. We tested whether environmental enrichment could reverse age-impaired rapid spatial search strategy ...acquisition concomitantly with hippocampal neurogenesis in rats. Young (5–8 months) and aged (20–22 months) male Fischer 344 rats were pair-housed and exposed to environmental enrichment ( n = 7 young, 9 aged) or housed individually ( n = 7 young, 7 aged) for 10 weeks. After 5 weeks, hidden platform trials (5 blocks of 3 trials; 15 m inter-block interval), a probe trial, and then visible platform trials (5 blocks of 3 trials; 15 m inter-block interval) commenced in the water maze. One week after testing, rats were given 5 daily intraperitoneal bromodeoxyuridine (50 mg/kg) injections and perfused 4 weeks later to quantify neurogenesis. Although young rats outperformed aged rats, aged enriched rats outperformed aged individually housed rats on all behavioral measures. Neurogenesis decreased with age but enrichment enhanced new cell survival, regardless of age. The novel correlation between new neuron number and behavioral measures obtained in a rapid water maze task among aged rats, suggests that environmental enrichment increases their ability to rapidly acquire and flexibly use spatial information along with neurogenesis.
To improve cancer care in Indiana, a telementoring program using the Extension for Community Healthcare Outcomes (ECHO) model was introduced in September 2019 to promote best-practice cancer ...prevention, screening, and survivorship care by primary care providers (PCPs). The aim of this study was to evaluate the program's educational outcomes in its pilot year, using Moore's Evaluation Framework for Continuing Medical Education and focusing on the program's impact on participants' knowledge, confidence, and professional practice. We collected data in 22 semi-structured interviews (13 PCPs and 9 non-PCPs) and 30 anonymous one-time surveys (14 PCPs and 16 non-PCPs) from the program participants (hub and spoke site members), as well as from members of the target audience who did not participate. In the first year, average attendance at each session was 2.5 PCPs and 12 non-PCP professionals. In spite of a relatively low PCP participation, the program received very positive satisfaction scores, and participants reported improvements in knowledge, confidence, and practice. Both program participants and target audience respondents particularly valued three features of the program: its conversational format, the real-life experiences gained, and the support received from a professional interdisciplinary community. PCPs reported preferring case discussions over didactics. Our results suggest that the Cancer ECHO program has benefits over other PCP-targetted cancer control interventions and could be an effective educational means of improving cancer control capacity among PCPs and others. Further study is warranted to explain the discrepancies among study participants' perceptions of the program's strengths and the relatively low PCP participation before undertaking a full-scale effectiveness study.
Traumatic injury is not only physically devastating, but also psychologically isolating, potentially leading to poor quality of life, depression and posttraumatic stress disorder (PTSD). Perceived ...social support (PSS) is associated with better outcomes in some populations. What is not known is if changes in PSS influence long-term outcomes following nonneurologic injury. We hypothesized that a single drop in PSS during recovery would be associated with worse quality of life.
This is a post hoc analysis of a prospectively collected database that included patients 18 years or older admitted to a Level I trauma center with Injury Severity Score (ISS) of 10 or higher, and no traumatic brain or spinal cord injury. Demographic and injury data were collected at the initial hospital admission. Screening for depression, PTSD, and Medical Outcomes Study Short Form 36 Mental Composite Score (MCS) were obtained at the initial hospitalization, 1, 2, 4, and 12 months postinjury. The Multidimensional Scale of Perceived Social Support (MSPSS) was obtained at similar time points. Patients with high MSPSS (>5) at baseline were included and grouped by those that ever reported a score ≤5 (DROP), and those that remained high (STABLE). Outcomes were determined at 4 and 12 months.
Four hundred eleven patients were included with 96 meeting DROP criteria at 4 months, and 97 at 1 years. There were no differences in sex, race, or injury mechanism. The DROP patients were more likely to be single (p = 0.012 at 4 months, p = 0.0006 at 1 year) and unemployed (p = 0.016 at 4 months, and p = 0.026 at 1 year) compared with STABLE patients. At 4 months and 1 year, DROP patients were more likely to have PTSD, depression, and a lower MCS (p = 0.0006, p < 0.0001).
Patients who have a drop in PSS during the first year of recovery have significantly higher odds of poor psychological outcomes. Identifying these socially frail patients provides an opportunity for intervention to positively influence an otherwise poor quality of life.
Therapeutic, Prognostic and Epidemiological, Level III.
Autoantibodies that bind the N-methyl-D-aspartate receptor (NMDAR) may underlie glutamate receptor hypofunction and related cognitive impairment found in schizophrenia. Exposure to neurotropic ...pathogens can foster an autoimmune-prone environment and drive systemic inflammation leading to endothelial barrier defects. In mouse model cohorts, we demonstrate that infection with the protozoan parasite, Toxoplasma gondii, caused sustained elevations of IgG class antibodies to the NMDAR in conjunction with compromised blood-gut and blood-brain barriers. In human cohorts, NMDAR IgG and markers of barrier permeability were significantly associated with T. gondii exposure in schizophrenia compared with controls and independently of antipsychotic medication. Combined T. gondii and NMDAR antibody seropositivity in schizophrenia resulted in higher degrees of cognitive impairment as measured by tests of delayed memory. These data underscore the necessity of disentangling the heterogeneous pathophysiology of schizophrenia so that relevant subsets eligible for NMDAR-related treatment can be identified. Our data aid to reconcile conflicting reports regarding a role of pathological NMDAR autoantibodies in this disorder.
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