piRNABank: a web resource on classified and clustered Piwi-interacting RNAs

Piwi-interacting RNAs (piRNAs) are expressed in mammalian germline cells and have been identified as key players in germline development. These molecules, typically of length 25–33 nt, associate with Piwi proteins of the Argonaute family to form the Piwi-interacting RNA complex. These small regulatory RNAs have been implicated in spermatogenesis, repression of retrotransposon transposition in germline cells, epigenetic regulation and positive regulation of translation and mRNA stability. piRNABank is a highly user-friendly resource which stores empirically known sequences and other related information on piRNAs reported in human, mouse and rat. The database supports organism and chromosome-wise comprehensive search features including accession numbers, localization on chromosomes, gene name or symbol, sequence homology-based search, clusters and corresponding genes and repeat elements. It also displays each piRNA or piRNA cluster on a graphical genome-wide map (http://pirnabank.ibab.ac.in/)

Functions of PIWI proteins in spermatogenesis

Recently, a significant understanding of the molecular mechanisms regulating spermatogenesis has been achieved utilizing small RNA molecules (small RNAs), including small interfering RNAs (siRNAs), microRNAs (miRNAs), and Piwi-interacting RNAs (piRNAs) which emerged as important regulators of gene expression at the post-transcriptional or translation level. piRNAs are only present in pachytene spermatocytes and round spermatids, whereas miRNAs are expressed abundantly in male germ cells throughout spermatogenesis. This review is aimed at providing a glimpse of piRNAs and their interacting family proteins such as PIWIL1, PIWIL2, and PIWIL4 in spermatogenesis

Child maltreatment and neglect in the United Arab Emirates and relationship with low self-esteem and symptoms of depression

Objectives: To our knowledge, this study is the first in the United Arab Emirates (UAE) to investigate the prevalence of child maltreatment in relation to depressive symptoms and self-esteem.Study design: Exposure to physical maltreatment, emotional abuse and neglect was evaluated in 518 adolescents (86% response rate) randomly selected from schools in Al Ain in the Emirate of Abu Dhabi. The Rosenberg self-esteem scale and the Beck Depression Inventory were used to measure self-esteem and depressive symptoms by using multivariate logistic regression analyses.Results: The mean age of study participants was 14.3 years. Emotional abuse was the most frequent form of maltreatment (33.9%), physical abuse (12.6%) and neglect (12.1%) followed. Male sex was a positive predictor of physical abuse (OR = 2.12; 95% CI 1.18-3.77), whilst higher maternal level of education was protective (OR = 0.40; 95% CI 0.19-0.86). Daily screen time (OR = 2.77; 95% CI 1.17-6.56) and tobacco smoking (OR = 1.86; 95% CI 1.09-3.18) positively predicted emotional abuse. Emotionally maltreated and neglected participants were less likely to report high level of self-esteem and more likely to report symptoms of depression.Conclusions: Child maltreatment in the UAE is of a similar magnitude to what reported in other countries around the world and significantly associated with low self-esteem and depressive symptoms

TDRD5 is required for retrotransposon silencing, chromatoid body assembly, and spermiogenesis in mice

Tdrd5-deficient mice develop a functional haploid genome despite spermiogenesis arrest at the round spermatid stage

A snapshot of summer 2020

Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The study aim was to understand the availability of personal protective equipment (PPE) and the levels of anxiety, depression, and burnout of healthcare workers (HCWs) in the United Arab Emirates (UAE). This study was an online‐based, cross‐sectional survey during July and August 2020. Participants were eligible from the entire country, and 1290 agreed to participate. The majority of HCWs were females aged 30–39 years old, working as nurses, and 80% considered PPE to be available. Twelve percent of respondents tested positive for SARS‐CoV‐2. Half of HCWs considered themselves physically tired (52.2%), reported musculoskeletal pain or discomfort (54.2%), and perceived moderate‐to‐high levels of burnout on at least one of three burnout domains (52.8%). A quarter of HCWs reported anxiety (26.3%) or depression (28.1%). HCWs reporting not having musculoskeletal pain, having performed physical activity, and higher scores of available PPE reported lower scores of anxiety, depression, and burnout. UAE HCWs experienced more access to PPE and less anxiety, depression, and burnout compared with HCWs in other countries. Study findings can be used by healthcare organizations and policymakers to ensure adequate measures are implemented to maximize the health and wellbeing of HCWs during the current COVID‐19 and future pandemics.publishersversionpublishe

Opposing effects of retinoic acid and FGF9 on Nanos2 expression and meiotic entry of mouse germ cells

In the mouse, three genes that are homologous to the Drosophila Nanos (Nos) gene have been identified. Deletion of one of these genes, Nanos2, results in male sterility, owing to loss of germ cells during fetal life. Before apoptosis, Nanos2-null gonocytes enter meiosis, suggesting that Nanos2 functions as a meiotic repressor. Here, we show that Nanos2 is continuously expressed in male germ cells from fetal gonocytes to postnatal spermatogonial stem cells. We observed that the promeiotic factor AtRA, an analog of retinoic acid (RA), downregulates NANOS2 levels, in both fetal and postnatal gonocytes, while promoting meiosis. Interestingly, FGF9, a growth factor crucial for sex differentiation and survival of fetal gonocytes, upregulates levels of NANOS2 in both male and female primordial germ cells (PGCs) and in premeiotic spermatogonia. This effect was paralleled by an impairment of meiotic entry, suggesting that FGF9 acts as an inhibitor of meiosis through the upregulation of Nanos2. We found that NANOS2 interacts with PUM2, and that these two proteins colocalize in the ribonucleoparticle and polysomal fractions on sucrose gradients, supporting the notion that they bind RNA. Finally, we found that recombinant NANOS2 binds to two spermatogonial mRNAs, Gata2 and Taf7l, which are involved in germ-cell differentiation

Differential Expression of Non-Coding RNAs and Continuous Evolution of the X Chromosome in Testicular Transcriptome of Two Mouse Species

BACKGROUND: Tight regulation of testicular gene expression is a prerequisite for male reproductive success, while differentiation of gene activity in spermatogenesis is important during speciation. Thus, comparison of testicular transcriptomes between closely related species can reveal unique regulatory patterns and shed light on evolutionary constraints separating the species. METHODOLOGY/PRINCIPAL FINDINGS: Here, we compared testicular transcriptomes of two closely related mouse species, Mus musculus and Mus spretus, which diverged more than one million years ago. We analyzed testicular expression using tiling arrays overlapping Chromosomes 2, X, Y and mitochondrial genome. An excess of differentially regulated non-coding RNAs was found on Chromosome 2 including the intronic antisense RNAs, intergenic RNAs and premature forms of Piwi-interacting RNAs (piRNAs). Moreover, striking difference was found in the expression of X-linked G6pdx gene, the parental gene of the autosomal retrogene G6pd2. CONCLUSIONS/SIGNIFICANCE: The prevalence of non-coding RNAs among differentially expressed transcripts indicates their role in species-specific regulation of spermatogenesis. The postmeiotic expression of G6pdx in Mus spretus points towards the continuous evolution of X-chromosome silencing and provides an example of expression change accompanying the out-of-the X-chromosomal retroposition

Cost per case or total cost? The potential of prevention of hand injuries in young children – Retrospective and prospective studies

<p>Abstract</p> <p>Background</p> <p>Health-care costs for hand and forearm injuries in young children are poorly documented. We examined costs in 533 children injured years 1996–2003.</p> <p>Methods</p> <p>Health-care costs and costs for lost productivity were retrospectively calculated in children from three catchment areas in Sweden. Seven case categories corresponding to alternative prevention strategies were constructed.</p> <p>Results</p> <p>Over time, diminishing number of ward days reduced the health-care cost per case. Among children, the cost of lost productivity due to parental leave was 14 percent of total cost. Fingertip injuries had low median costs but high total costs due to their frequency. Complex injuries by machine or rifle had high costs per case, and despite a low number of cases, total cost was high. Type of injury, surgery and physiotherapy sessions were associated with variations in health-care cost. Low age and ethnic background had a significant effect on number of ward days.</p> <p>Conclusion</p> <p>The costs per hand injury for children were lower compared to adults due to both lower health-care costs and to the fact that parents had comparatively short periods of absence from work. Frequent simple fingertip injuries and rare complex injuries induce high costs for society. Such costs should be related to costs for prevention of these injuries.</p