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Chronic stress is a universal condition commonly associated with many psychiatric diseases. An extensive body of evidence discussed hippocampal affection upon chronic stress exposure, however, the underlying molecular pathways still need to be identified. We investigated the impact of chronic stress on miR200/BMP/Olig‐2 signaling and hippocampal myelination. We also compared the effects of chronic administration of amitriptyline and cholecalciferol on chronically stressed hippocampi. Both amitriptyline and cholecalciferol significantly decreased serum cortisol levels, reduced immobility time in the forced swim test, increased the number of crossed squares in open field test, decreased the hippocampal expression of bone morphogenetic protein 4 (BMP4) and its messenger RNA (mRNA) levels, reduced miR200 expression as compared to untreated chronically stressed rats. Also, both drugs amended the hippocampal neuronal damage, enhanced the surviving cell count, and increased the pyramidal layer thickness of Cornu Ammonis subregion 1 (CA1) and granule cell layer of the dentate gyrus. Cholecalciferol was more effective in increasing the area percentage of myelin basic protein (MBP) and Olig‐2 positive cells count in hippocampi of chronic stress‐exposed rats than amitriptyline, thus enhancing myelination. We also found a negative correlation between the expression of BMP4, its mRNA, miR200, and the immunoexpression of MBP and Olig‐2 proteins. This work underscores the amelioration of the stress‐induced behavioral changes, inhibition of miR200/BMP4 signaling, and enhancement of hippocampal myelination following chronic administration of either amitriptyline or cholecalciferol, though cholecalciferol seemed more effective in brain remyelination. [ABSTRACT FROM AUTHOR]

Two clusters of mortality among endangered tūturuatu/tchūriwat'/shore plover (Thinornis novaeseelandiae) have occurred at captive breeding facilities around New Zealand in recent years. In the first, four chicks died at Pūkaha National Wildlife Centre (Mount Bruce, NZ) in February 2016, and in the second five adult birds at the Cape Sanctuary (Cape Kidnappers, NZ) died in 2022. In 2016, four chicks were noted to become weak, have increased vocalisations and closed eyes prior to death. The remaining chicks were treated for 5 days with amoxycillin/clavulanate orally twice daily. Water containers and brooders were cleaned and disinfected with chlorhexidine. No further mortality was seen. In the 2022 cluster, three adult breeding birds died acutely and five others showed inappetence, weight loss and diarrhoea approximately 10 days after heavy rains flooded the local river. The five birds were treated with amoxycillin/clavulanate orally twice daily and oral fluids for 5 days. Two birds died and three survived. No breeding occurred in the aviaries in the following season. In 2016, the chicks showed pulmonary changes ranging from congestion and oedema to heterophilic inflammation consistent with septicaemia. In 2022, the adult birds showed proliferation of bacteria in the distal small intestine associated with mucosal ulceration and heterophilic infiltration. Acid-fast staining of the caecal contents in one bird showed organisms consistent with Cryptosporidium spp. Aerobic bacterial cultures of the lung and liver of two affected chicks carried out in 2016 showed heavy growth of Plesiomonas shigelloides. The same organism was cultured from water trays and holding tanks containing water boatmen (Sigara arguta) on which the chicks were fed. In 2022, cultures from the livers of three dead birds each showed a mixed bacterial growth with differing dominant organisms (Aeromonas sobria, Hafnia alvei, Citrobacter freundii and an Enterococcus sp.). PCR and sequencing confirmed Cryptosporidium parvum in the caecum of one bird. Fresh faeces from 24 breeding birds from the captive breeding facilities were negative by PCR for Cryptosporidium spp. The captive breeding facilities obtain water for the aviaries and aquatic invertebrates to feed to the chicks from local freshwater sources. Water quality testing at the Cape Sanctuary revealed concentrations of faecal indicator bacteria in excess of safe drinking water guidelines, with peaks following heavy rainfall. Fluctuations in water quality associated with mammalian faecal bacteria can adversely affect bird health and impact on captive rearing of endangered wildlife. [ABSTRACT FROM AUTHOR]

Summary: Heat shock factors (Hsfs) are transcription factors that regulate responses to heat shock and other environmental stimuli. Four heat shock factors (Hsf1-4) have been characterized from vertebrates to date. In addition to stress response, they also play important roles in development and gametogenesis. Here, we study the fifth member of heat shock factor family, Hsf5, using zebrafish as a model organism. Mutant hsf5−/− males, generated by CRISPR/Cas9 technique, were infertile with drastically reduced sperm count, increased sperm head size, and abnormal tail architecture, whereas females remained fertile. We show that Hsf5 is required for progression through meiotic prophase 1 during spermatogenesis as suggested by the accumulation of cells in the leptotene and zygotene-pachytene stages and increased apoptosis in post-meiotic cells. hsf5−/− mutants show gonadal misregulation of a substantial number of genes with roles in cell cycle, apoptosis, protein modifications, and signal transduction, indicating an important role of Hsf5 in early stages of spermatogenesis. : Saju et al. show that heat shock factor 5 (hsf5) is predominantly expressed in testis. Loss of Hsf5 leads to a drastic reduction in sperm counts and severe morphological abnormalities in spermatozoa, leading to infertility. Hsf5 appears to be required for proper progression of meiosis-I during spermatogenesis. Keywords: Hsf5, fish sex, reproduction, gonad differentiation, meiosis, CRISPR/Cas9, sexual development

Purpose: A new magnetic resonance imaging (MRI) based scoring system for temporomandibular joint (TMJ) internal derangement was developed to predict disease severity and the likelihood of invasive treatment. Patients and methods: Reports and images from bilateral TMJ MRI studies of 100 consecutive patients with TMJ pain were retrospectively reviewed. A Temporomandibular Joint Internal Derangement Score (TIDS) score was composed of 6 MRI characteristics: joint effusion, disc displacement, disc nonrecapture, disc degenerative changes, abnormal condyle translation, and condyle arthritis. The primary endpoint was whether disease severity merited invasive treatment (arthrocentesis, arthroscopy, arthroplasty, or discectomy). Primary analyses were conducted as univariate regression, with the level of significance set at p < .05. Multivariate regression was also used to assess the impacts of each variable upon the need for invasive treatment. Results: Invasive treatment was performed in 29 patients and planned in an additional 9 patients. Patients with clinical bilateral pathology were no more likely to undergo invasive treatment than those with unilateral clinical pathology. Statistically significant correlations were found between bilateral invasive treatment and the presence of bilateral joint effusions (p = 0.0037) and disc displacement (p = 0.014), as well as with increasing values of right TIDS (p = 0.0015) and bilateral TIDS (p = 0.0090). Bilateral TIDS of greater than 6 was correlated with both bilateral invasive treatment (p = 0.0033) and with invasive treatment of any kind (p = 0.041). In each instance of TIDS > 6, the patient demonstrated multiple signs of bilateral TMJ pathology. On multivariate regression, only disc recapture failed to trend towards statistical significance in both the six and twelve component regressions, which trended towards significance only in the twelve component analysis. Conclusion: A TIDS score was developed to serve as an adjunct to the clinical assessment of TMJ pathology. Bilateral TIDS score greater than 6 was statistically significantly correlated with the severity of TMJ pathology.

A reduction in daily caloric or nutrient intake has been observed to promote health benefits in mammals and other vertebrates. Feed Restriction (FR), whereby the overall food intake of the organism is reduced, has been explored as a method to improve metabolic and immune health, as well as to optimize productivity in farming. However, less is known regarding the molecular and physiological consequences of FR. Using the model organism, Danio rerio, we investigated the impact of a short-term (month-long) FR on growth, gut morphology and gene expression. Our data suggest that FR has minimal effects on the average growth rates, but it may affect weight and size heterogeneity in a sex-dependent manner. In the gut, we observed a significant reduction in gut circumference and generally lower mucosal heights, whereas other parameters remained unchanged. Gene Ontology (GO), EuKaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified numerous metabolic, reproductive, and immune response pathways that were affected by FR. These results broaden our understanding of FR and contribute towards growing knowledge of its effects on vertebrate health.

The Asian seabass (or barramundi; Lates calcarifer) is a marine teleost and a popular food fish in Southeast Asia and Australia. To date, comprehensive genome and transcriptome sequence information has not been available for this species in public repositories. Here, we report a comprehensive de novo transcriptome assembly of the Asian seabass. These data will be useful for the development of molecular tools for use in aquaculture of Asian seabass as well as a resource for genome annotation. The transcriptome was obtained from sequences generated from organs of multiple individuals using three different next-generation sequencing platforms (454-FLX Titanium, SOLiD 3+, and paired-end Illumina HiSeq 2000). The assembled transcriptome contains >80% of the expected protein-coding loci, with 58% of these represented by a predicted full-length cDNA sequence when compared to the available Nile tilapia RefSeq dataset. Detailed descriptions of the various steps involved in sequencing and assembling a transcriptome are provided to serve as a helpful guide for transcriptome projects involving de novo assembly of short sequence reads for non-model teleosts or any species of interest.

Summary: As complete absence of germ cells leads to sterile males in zebrafish, we explored the relationship between primordial germ cell (PGC) number and sexual development. Our results revealed dimorphic proliferation of PGCs in the early zebrafish larvae, marking the beginning of sexual differentiation. We applied morpholino-based gene knockdown and cell transplantation strategies to demonstrate that a threshold number of PGCs is required for the stability of ovarian fate. Using histology and transcriptomic analyses, we determined that zebrafish gonads are in a meiotic ovarian stage at 14 days postfertilization and identified signaling pathways supporting meiotic oocyte differentiation and eventual female fate. The development of PGC-depleted gonads appears to be restrained and delayed, suggesting that PGC number may directly regulate the variability and length of gonadal transformation and testicular differentiation in zebrafish. We propose that gonadal transformation may function as a developmental buffering mechanism to ensure the reproductive outcome. : In this article, Orban, Tzung, and colleagues report that the number of primordial germ cells (PGCs) plays a regulatory role during sexual differentiation in zebrafish. Partial depletion of PGCs leads to male bias, and a threshold number is required for ovarian development. They further provide evidence suggesting that the PGC-depleted gonads might undergo a less pronounced gonadal transformation than WTs.

[This corrects the article DOI: 10.1371/journal.pgen.1005954.].

Many graduates of various levels and disciplines appear unable to practically apply their knowledge in problem solving situations. However, few education systems are adopting modern education practices such as visualization skills that intrinsically motivate and engage learners and are at the same time flexible enough to consider students' aspirations and interests. Such systems make learning more relevant, meaningful and enjoyable to the learners and improve exit performances. In such a system, the role of the teacher is that of a facilitator and not instructor. The purpose of this study was to identify three-dimensional (3D) visualizations that could aid comprehension and perception of cytoplasmic structure, geo-referenced graphical data and understanding of spatial relationships in Biology. A qualitative research approach was used to ascertain from university lecturers (n = 13) what convictions, beliefs and experiences they have had with their students that related to the use of visualization skills. Skills most required included interpretation of 2 and 3D structures as well as their rotation in space. A survey was also carried out among cell biology first year students (n = 145) and second year students (n = 45) of the School of Life and Environmental Studies at the University of Natal in order to precisely determine aspects of three-dimensionality and visual skills suspected to cause conceptual difficulties. Quantitative data analysis (the non parametric Mann-Whitney U-Wilcoxon Test at a confidence level of 0.05) showed that the most deficient skills in the learners included pattern folding (projecting 2D material into 3D objects), orientation of form (identifying 3D objects that are oriented differently) and rotation (identifying 3D objects from top and front views). These findings corroborate qualitative analysis of lecturers' opinions and convictions. An educational computer game is proposed with the aim of ameliorating these problems. It is recommended that visualization skills should be incorporated into the Biology curriculum for all undergraduate students within the first year of the course. (Contains 4 figures.)

Exposure of children to their parents' intimate partner violence (IPV) is recognized as an adverse childhood experience that has a significant impact on the overall healthy development of the children and this research summarizes all relevant literature to determine the prevalence, impacts, risks, and protective factors of adolescents subjected to parental IPV since childhood. The literature in this scoping was scrutinized based on both inclusion, exclusion criteria. Almost 15 articles were reviewed out of 118 related literature sourced from electronic databases such as PubMed, Scopus, Research Gate, and Google Scholar published in the year 2016–2021. The search method followed Mays, Roberts, and Popay's process of gathering relevant literature and mapping important ideas to capture the available data in a study topic, especially the one which lacked proper evaluation. The results of this review of the literature indicate that parental IPV is a pervasive problem that impairs the adolescent's overall well-being. It also highlights a range of protective factors that can mitigate the impact of parental IPV. The findings of this scoping review have implications for practice and policy. Given the enormous scope and burden of children's parental IPV exposure, intervention techniques to safeguard this vulnerable population and enhance well-being are urgently needed. [ABSTRACT FROM AUTHOR]

Asian seabass (Lates calcarifer) is a food fish of increasing aquaculture importance. In order to improve our understanding on the digestive system and feeding of this species, morphological and histological features of the gut were studied. Morphologically, the Asian seabass gut is defined by a short and muscular esophagus, well-developed stomach and comparatively short intestine. Mucous secreting goblet cells reactive to PAS (Periodic Acid Schiff) and AB (Alcian Blue) stain were present throughout the esophagus. The stomach was sac-like and could be distinguished into the cardiac, fundic and pyloric regions. Gastric glands and mucus cells were predominately present in the cardiac and fundic regions. Five finger-like pyloric caeca were present between the stomach and intestine. The intestine was a short, tubular structure with no morphological differences between the various regions. Histologically, the intestinal regions were similar, the main difference being in the number of goblet cells that increased from anterior to posterior intestine, with 114 ± 9, 153 ± 7 and 317 ± 21 goblet cells in the anterior, mid and posterior regions, respectively. The intestinal epithelium stained positively for PAS, but the staining was stronger for acidic glycoproteins. The rectum was similar to intestine, except for increased goblet cell numbers (anterior rectum: 529 ± 26; posterior rectum: 745 ± 29). Gut morpho-histology did not respond to salinity changes, however, there was a significant reduction of mucosal height, goblet cell numbers and muscularis thickness upon food deprivation.

We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species' native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics.

As nutrition-related expenses constitute the majority of the costs for aquaculture farms, it is essential for them to use feeds that provide an ideal combination of nutrients for the species of choice. In this study, the relative effect of consuming three different pelleted feeds (B, C and D) in comparison to frozen baitfish (A; control) were compared on juvenile Asian seabass (77.3 ± 22.4g) that were selected for increased growth rate over two generations. Our objectives were: 1) to evaluate the effects of different pelleted feeds based on overall physiological changes and nutritional quality of fillets; 2) improve our understanding of the underlying mechanisms with transcriptomic analysis; 3) if possible, identify the feed type that supports the growth of these fishes without substantially reducing the nutritional quality of fillet. The growth performance, fatty acid composition of fillet, hepatic histology and transcriptome of the fishes (Groups A-D) were analyzed. The majority of fatty acids of the fillets, except γ-linolenic acid (GLA, C18:3n6), correlated significantly with the respective diets. Asian seabass fed Feed C showed highest specific growth rate (SGR) and feed conversion efficiency (FCE) with closest histology and transcriptomic profile to control, but their fillet contained the highest n6/n3 ratio. When the liver-based transcriptomes were analyzed, a complex set of differentially expressed genes were detected between groups fed pelleted feeds and controls as well as among the pellet-fed groups themselves. Significant enrichment of genes with growth-related function tallied with the morphological data measured. When compared with control (Group A), 'Biosynthesis of unsaturated fatty acids' and 'Steroid biosynthesis' pathways were significantly enriched in pellet-fed groups. Reduced goblet cell numbers were observed in the gut of pellet-fed fish compared to controls and fads6 was found to be a suitable candidate gene to separate wild-caught Asian seabass, from pellet-fed ones. These results provide insights for researchers on the various effects of feeds on the biochemistry and global gene expression of the fish and potentially for seabass farms to make more informed feed choices.