Pachytene PIWI-interacting RNAs (piRNAs), which comprise >80% of small RNAs in the adult mouse testis, have been proposed to bind and regulate target RNAs like microRNAs, cleave targets like short ...interfering RNAs or lack biological function altogether. Although piRNA pathway protein mutants are male sterile, no biological function has been identified for any mammalian piRNA-producing locus. Here, we report that males lacking piRNAs from a conserved mouse pachytene piRNA locus on chromosome 6 (pi6) produce sperm with defects in capacitation and egg fertilization. Moreover, heterozygous embryos sired by pi6
fathers show reduced viability in utero. Molecular analyses suggest that pi6 piRNAs repress gene expression by cleaving messenger RNAs encoding proteins required for sperm function. pi6 also participates in a network of piRNA-piRNA precursor interactions that initiate piRNA production from a second piRNA locus on chromosome 10, as well as pi6 itself. Our data establish a direct role for pachytene piRNAs in spermiogenesis and embryo viability.
The present study examined the mediating role of intolerance of uncertainty and fear of COVID-19 in the relationship between self-compassion and well-being. The participants were comprised of 667 ...Turkish individuals (465 females and 202 males; aged between 18 and 73 years) from 75 of 81 cities in Turkey. The model was investigated using bootstrapping. The results showed that self-compassion, intolerance of uncertainty, fear of COVID-19, and well-being are significantly interrelated. Moreover, a serial mediation was found among the variables: individuals with a growth self-compassion to report lower intolerance of uncertainty, which further decreased perceived fear of COVID-19, and subsequently weakened well-being. Results are discussed in the context of COVID-19 and the well-being literature, and theoretical and practical implications were also provided.
Since discovery of the first antibiotic drug, penicillin, in 1928, a variety of antibiotic and antimicrobial agents have been developed and used for both human therapy and industrial applications. ...However, excess and uncontrolled use of antibiotic agents has caused a significant growth in the number of drug resistant pathogens. Novel therapeutic approaches replacing the inefficient antibiotics are in high demand to overcome increasing microbial multidrug resistance. In the recent years, ongoing research has focused on development of nano-scale objects as efficient antimicrobial therapies. Among the various nanoparticles, silver nanoparticles have gained much attention due to their unique antimicrobial properties. However, concerns about the synthesis of these materials such as use of precursor chemicals and toxic solvents, and generation of toxic byproducts have led to a new alternative approach, green synthesis. This eco-friendly technique incorporates use of biological agents, plants or microbial agents as reducing and capping agents. Silver nanoparticles synthesized by green chemistry offer a novel and potential alternative to chemically synthesized nanoparticles. In this review, we discuss the recent advances in green synthesis of silver nanoparticles, their application as antimicrobial agents and mechanism of antimicrobial mode of action.
The world is currently experiencing a pandemic of an infectious disease called COVID-19 which has drawn global intensive attention. While global attention is largely focusing on the effects of the ...coronavirus on physical health, the impacts of the coronavirus on psychological health cannot be overlooked. Therefore, this study aims to adapt the Fear of COVID-19 Scale into Turkish and investigate the relationships between fear of COVID-19, psychological distress, and life satisfaction. Data were collected by convenience sampling method, which allowed us to reach total 1304 participants, aged between 18 and 64 years, from 75 cities in Turkey. In the adaptation process of the Fear of COVID-19 Scale, confirmatory factor analysis, Item Response Theory, convergent validity, and reliability (Cronbach’s α, McDonald’s ω, Guttmann’s λ6, and composite reliability) analyses were performed. Additionally, the mediating role of psychological distress on the relationship between fear of COVID-19 and life satisfaction was tested. The uni-dimensionality of the 7-item scale was confirmed on a Turkish sample. Item Response Theory revealed that all items were coherent and fit with the model. The results indicated that the Turkish version of the scale had satisfactory reliability coefficients. The fear of COVID-19 was found to be associated with psychological distress and life satisfaction. Results indicated that the Turkish version of the Fear of COVID-19 Scale had strong psychometric properties. This scale will allow mental health professionals to do research on the psychological impacts of COVID-19 in Turkey.
A novel ratiometric colorimetric and fluorescent dual probe based on Eriochrome Black T (EBT)–Eu3+ complex was designed to detect dipicolinic acid (DPA), a major constituent of bacterial spores, with ...high sensitivity and selectivity. UV–vis titration experiments demonstrated that EBT and Eu3+ ions formed a 1:1 coordination pair in water. In the presence of Eu3+ ions, the blue solution of EBT changed to magenta, however, upon the addition of DPA, the magenta color changed to blue immediately and characteristic fluorescence emission from DPA–Eu3+ complex was observed. In addition, the sensitivity of the system was further evaluated on Geobacillus stearothermophilus spores and as low as 2.5 × 105 spores were detected.
In the male germ cells of placental mammals, 26-30-nt-long PIWI-interacting RNAs (piRNAs) emerge when spermatocytes enter the pachytene phase of meiosis. In mice, pachytene piRNAs derive from ~100 ...discrete autosomal loci that produce canonical RNA polymerase II transcripts. These piRNA clusters bear 5' caps and 3' poly(A) tails, and often contain introns that are removed before nuclear export and processing into piRNAs. What marks pachytene piRNA clusters to produce piRNAs, and what confines their expression to the germline? We report that an unusually long first exon (≥ 10 kb) or a long, unspliced transcript correlates with germline-specific transcription and piRNA production. Our integrative analysis of transcriptome, piRNA, and epigenome datasets across multiple species reveals that a long first exon is an evolutionarily conserved feature of pachytene piRNA clusters. Furthermore, a highly methylated promoter, often containing a low or intermediate level of CG dinucleotides, correlates with germline expression and somatic silencing of pachytene piRNA clusters. Pachytene piRNA precursor transcripts bind THOC1 and THOC2, THO complex subunits known to promote transcriptional elongation and mRNA nuclear export. Together, these features may explain why the major sources of pachytene piRNA clusters specifically generate these unique small RNAs in the male germline of placental mammals.
The concentration of nitrite (NO2−) ions above allowable limits in water resources and food stuffs is considered hazardous and has been proven to be of great threat to the environment and public ...health. In this work, an acenaphtho 1,2-d imidazole derivative (1) as a ratiometric colorimetric probe is developed. UV–Vis experiments demonstrate that the probe 1 shows excellent selectivity toward NO2− in the presence of other potential interfering species, a rapid response (20 s) and a low detection limit (100 nM) by a distinct visual color change with a bathochromic shift of 120 nm from colorless to intense yellow. Besides, this probe is further used for the quantification of nitrite ions in environmental water resources such as tap water, underground water, and surface water samples. The high recoveries (96–99% with relative standard deviations (RSD) of <2.0%) make the probe 1 a promising candidate for practical applications in daily life in the detection of nitrite ions.
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•A ratiometric and colorimetric probe for sensing NO2− ions is developed.•A distinct visual color change from colorless to intense yellow is observed.•The sensor exhibited high sensitivity (LOD = 100 nM) and remarkable selectivity.•The sensor has rapid response time (<30 s) and fast reaction kinetics.•The sensor was further used for detecting NO2− ions in different water resources.
Firm-specific information has a damped effect on business group-affiliated firms’ stock prices. Such firms’ idiosyncratic stock returns are less responsive to idiosyncratic commodity price shocks ...than are the idiosyncratic returns of otherwise similar unaffiliated firms in the same country and commodity-sensitive industry. Using global commodity shocks means we assess responses to common idiosyncratic shocks of the same magnitude, frequency, and observability. Further identification follows from difference-in-difference tests exploiting successful and matched exogenously failed control block transactions. We conclude that business group firms’ stock prices provide less firm-specific information to capital providers and managers.
In animals, PIWI-interacting RNAs (piRNAs) of 21-35 nucleotides in length silence transposable elements, regulate gene expression and fight viral infection. piRNAs guide PIWI proteins to cleave ...target RNA, promote heterochromatin assembly and methylate DNA. The architecture of the piRNA pathway allows it both to provide adaptive, sequence-based immunity to rapidly evolving viruses and transposons and to regulate conserved host genes. piRNAs silence transposons in the germ line of most animals, whereas somatic piRNA functions have been lost, gained and lost again across evolution. Moreover, most piRNA pathway proteins are deeply conserved, but different animals employ remarkably divergent strategies to produce piRNA precursor transcripts. Here, we discuss how a common piRNA pathway allows animals to recognize diverse targets, ranging from selfish genetic elements to genes essential for gametogenesis.
Male gametogenesis, spermatogenesis, is a stepwise developmental process to generate mature sperm. The most intricate process of spermatogenesis is meiosis during which two successive cell divisions ...ensue with dramatic cellular and molecular changes to produce haploid cells. After entry into meiosis, several forms of regulatory events control the orderly progression of meiosis and the timely entry into post-meiotic sperm differentiation. Among other mechanisms, changes to gene expression are controlled by key transcription factors. In this review, we will discuss the gene regulatory mechanisms underlying meiotic entry, meiotic progression, and post-meiotic differentiation with a particular emphasis on the MYBL1/TCFL5 regulatory architecture and how this architecture involves in various forms of transcription network motifs to regulate gene expression.
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