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Introduction: Computational studies were performed to investigate the unknown status of endosomal and cell surface receptors in SARS-CoV-2 infection. The interactions between Toll-like receptors (TLRs)-4/7/8/9 or ACE2 receptor and different SARS-CoV-2 variants were investigated. Methods: The RNA motifs for TLR7, TLR8 and a CpG motif for TLR9 were analyzed in different variants. Molecular docking and molecular dynamics (MD) simulations were performed to investigate receptor-ligand interactions. Results: The number of motifs recognized by TLR7/8/9 in the Alpha, Delta and Iranian variants was lower than in the wild type (WT). Docking analysis revealed that the Alpha, Delta and some Iranian spike variants had a higher affinity for ACE2 and TLR4 than the WT, which may account for their higher transmission rate. The MD simulation also showed differences in stability and structure size between the variants and the WT, indicating potential variations in viral load. Conclusion: It appears that Alpha and some Iranian isolates are the variants of concern due to their higher transmissibility and rapid spread. The Delta mutant is also a variant of concern, not only because of its closer interaction with ACE2, but also with TLR4. Our results emphasize the importance of ACE2 and TLR4, rather than endosomal TLRs, in mediating the effects of different viral mutations and suggest their potential therapeutic applications. [ABSTRACT FROM AUTHOR]

Chicken gut microbiota is affected by factors such as diets, environmental,and bird age. In the current study, the effects of age and region on the ileum bacterial population of broiler chickens were investigated. A total of 2679 chickens in four geographical regions of Iran were sacrificed in the first to eighth week of age. Stool samples were collected and DNA was extracted and analyzed for the detection of Lactobacillus, Enterococcaceae, Clostridiaceae, Streptococcaceae, and Actinobacteria, using specific primers and probes. Purified amplicons were quantified by QuantiFluor® and pooled for sequencing. Findings showed that L. acidophilus was the dominant bacterium during the first four weeks, and was substituted with L. crispatus and L. salivarius in the next four weeks. So, the Lactobacillus family was the most dominant bacteria at all ages showing its essential role in chicken physiology. The age of chickens significantly affected the percentage of L. crispatus, L. acidophilus, L. salivarius, Clostridiaceae, Enterococcaceae, Streptococcaceae, and Actinobacteria. The breeding region influenced Streptococcaceae, with the highest percentage in the hot region. Chicken weight had a significant effect on Enterococcaceae. Broiler breeder age and distance to the nearest farm had no effect on ileum bacterial populations. This study showed there are several factors during the broiler breeding period that have an impact on microbial population changes at different ages. [ABSTRACT FROM AUTHOR]

The Clostridium genus is composed of a large spectrum of heterogeneous bacteria. They are Gram-positive, mostly mesophilic, and anaerobic spore-forming strains. Clostridia are widely distributed in oxygen-free habitats. They are found principally in the soil and intestines of ruminants as normal flora, but also are the cause of several infections in humans. The infections produced by important species in humans include botulism, tetanus, pseudomembranous colitis, antibiotics-associated diarrhea, and gas gangrene. Immunization with toxoid or bacterin-toxoid or genetically modified or other vaccines is a protective way against clostridial infection. Several experimental or commercial vaccines have been developed worldwide. Although conventional vaccines including toxoid vaccines are very important, the new generation of vaccines is an effective alternative to conventional vaccines. Recent advances have made it possible for new vaccines to increase immunogenicity. This review discusses briefly the important species of clostridia in humans, their toxins structure, and vaccine development and usage throughout the world. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) that detect pathogen associated molecular patterns and activate innate and adaptive immune system. Coronaviruses can be detected via TLRs through their biological materials such as ribonucleic acids, glycoproteins and CpG motifs. During COVID-19 pandemic, different strategies have been used for combating SARS-CoV-2 to initiate a proper and balanced immune response through TLRs or other PRRS. Understanding the trigerred TLR signaling pathways during coronavirus infections would assist to understand the control and defense mechanisms against these viral diseases. In this review, we summarize different studies on the use and function of of TLRs and their signaling pathways as vaccines/adjuvants or therapeutic agents against coronavirus infections. Since the pandemic is ongoing and there still many unknowns with respect to COVID-19 immunology, we highlight the role of TLRs and their agonists/antagonists in previous coronavirus infections, and show their potential role in the current SARS-CoV-2 immunopathology. [ABSTRACT FROM AUTHOR]

Clostridium is a Gram-positive, rod-shaped, anaerobic, and spore-forming bacterium, which is found in the surrounding environments throughout the world. Clostridium species cause botulism, tetanus, enterotoxaemia, gas gangrene, necrotic enteritis, pseudomembranous colitis, blackleg, and black disease. Clostridium infection causes severe economic losses in livestock and poultry industries. Vaccination seems to be an effective way to control Clostridial diseases. This review discusses the toxins and vaccine development of the most common pathogenic Clostridium species in animals, including Clostridium perfringens, Clostridium novyi, Clostridium chauvoei, and Clostridium septicum. In this comprehensive study, we will review different kinds of clostridial toxins and the vaccines that are experimentally or practically available and will give a short description on each vaccine focusing on its applications, advantages, and disadvantages. [ABSTRACT FROM AUTHOR]

Maternal effect genes have highly impressive effects on pre-implantation development.Filia/Ecat1/Khdc3lis a maternal effect gene found in mouse oocytes and embryos, loss of which causes a 50% decrease in fertility. In the present study, we investigatedFiliamRNA expression in bovine oviduct, 30- to 40-day fetus, liver, heart, lung, and oocytes (as a positive control), by RT-PCR and detected it only in oocytes. A 443 bp fragment was amplified only in oocytes and was sequenced as a part of bovine predictedFiliamRNA. We analyzed bovine and ovine Filia N-terminal peptide sequence in PHYRE2, and a KH domain was predicted. Protein alignment using ClustalW indicated a highly identical N-terminal extention between the 2 species. Immunohistochemical analysis using anti-bovine Filia antibody showed the expression of Filia protein in the zone surrounding the nuclear membrane, and in the subcortex of ovine oocytes of primary and antral follicles. However, in the bovine, Filia has been found through the oocyte cytoplasm of antral follicles, and here it is further confirmed in the primary follicles. Our data suggests a difference in Filia expression pattern between cow and sheep, although the sequence is highly conserved. [ABSTRACT FROM AUTHOR]

• microRNAs (miRNAs) are one of the molecular participants involved in regulating the translational process during oocyte and early embryo development. • Cellular proteins and the mRNAs that encode them are key factors in oocyte and sperm development. • MiRNAs have been identified as a group of testosterone-dependent disruptors in SCs that play an essential role in androgen-mediated processes. Cellular proteins and the mRNAs that encode them are key factors in oocyte and sperm development, and the mechanisms that regulate their translation and degradation play an important role during early embryogenesis. There is abundant evidence that expression of microRNAs (miRNAs) is crucial for embryo development and are highly involved in regulating translation during oocyte and early embryo development. MiRNAs are a group of short (18–24 nucleotides) non-coding RNA molecules that regulate post-transcriptional gene silencing. The miRNAs are secreted outside the cell by embryos during preimplantation embryo development. Understanding regulatory mechanisms involving miRNAs during gametogenesis and embryogenesis will provide insights into molecular pathways active during gamete formation and early embryo development. This review summarizes recent findings regarding multiple roles of miRNAs in molecular signaling, plus their transport during gametogenesis and embryo preimplantation. [ABSTRACT FROM AUTHOR]

Melatonin is a hormone mainly secreted by the pineal gland during the circadian cycle, with low levels during the daytime and prominent levels during the night. It is involved in numerous physiological functions including the immune system, circadian rhythm, reproduction, fertilization, and embryo development. In addition, melatonin exerts anti-inflammatory and antioxidant effects inside the body by scavenging reactive oxygen and reactive nitrogen species, increasing antioxidant defenses, and blocking the transcription factors of pro-inflammatory cytokines. Its protective activity has been reported to be effective in various reproductive biotechnological processes, including in vitro maturation (IVM), embryo development, and survival rates. In this comprehensive review, our objective is to summarize and debate the potential mechanism and impact of melatonin on oocyte maturation and embryo development through various developmental routes in different mammalian species., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)