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Mammalian oocyte activation is a critical process occurring post-gamete fusion, marked by a sequence of cellular events initiated by an upsurge in intracellular Ca2+. This surge in calcium orchestrates the activation/deactivation of specific kinases, leading to the subsequent inactivation of MPF and MAPK activities, alongside PKC activation. Despite various attempts to induce artificial activation using distinct chemical compounds as Ca2+ inducers and/or Ca2+-independent agents, the outcomes have proven suboptimal. Notably, incomplete suppression of MPF and MAPK activities persists, necessitating a combination of different agents for enhanced efficiency. Moreover, the inherent specificity of activation methods for each species precludes straightforward extrapolation between them. Consequently, optimization of protocols for each species and for each technique, such as PA, ICSI, and SCNT, is required. Despite recent strides in camelid biotechnologies, the field has seen little advancement in chemical activation methods. Only a limited number of chemical agents have been explored, and the effects of many remain unknown. In ICSI, despite obtaining blastocysts with different chemical compounds that induce Ca2+ and calcium-independent increases, viable offspring have not been obtained. However, SCNT has exhibited varying outcomes, successfully yielding viable offspring with a reduced number of chemical activators. This article comprehensively reviews the current understanding of the physiological activation of oocytes and the molecular mechanisms underlying chemical activation in mammals. The aim is to transfer and apply this knowledge to camelid reproductive biotechnologies, with emphasis on chemical activation in PA, ICSI, and SCNT.

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Crotalicidin is a cathelicidin-related anti-infective (antimicrobial) peptide expressed in the venom glands of the South American rattlesnake Crotalus durissus terrificus. Congener peptides of crotalicidin, named vipericidins, are found in other pit vipers inhabiting South America. Crotalicidin is active against bacteria and pathogenic yeasts and has anti-proliferative activity for some cancer cells. The structural dissection of crotalicidin produced fragments (e.g., Ctn [15-34]) with multiple biological functionalities that mimic the native peptide. Another structural characteristic of crotalidicin and congeners is a unique repetitive stretch of amino acid sequences in tandem embedded in their primary structures. One of the encrypted vipericidn peptides (Ctn [1-9]) was synthesized, and the analog covalently conjugated with rhodamine B (RhoB-Ctn [1-9]) displayed considerable antimicrobial activity and selective cytotoxicity. Methods to evaluate antimicrobial peptides' toxicity include lysis of red blood cells (hemolysis) in vitro and cytotoxicity of healthy cultured cells (e.g., fibroblasts). Here, as a non-conventional model of toxicity, the bovine oocytes were exposed to two standardized concentrations of RhoB-Ctn [1-9], and embryo viability and development at its first stage of cleavage (division of cells) and blastocyst formation were evaluated. Oocytes treated with peptide at 10 and 40 µM induced cleavage rates of 44.94% and 51.53%, resulting in the formation of blastocysts of 7.07% and 11.73%, respectively. Light sheet microscopy and in silico prediction analysis indicated that RhoB-Ctn [1-9] peptide interacts with zona pellucida and internalizes into bovine oocytes and developing embryos. The ADMET prediction estimated good bioavailability of RhoB-Ctn [1-9]. In conclusion, the peptide appeared harmless to bovine oocytes and, remarkably, activated the parthenogenesis in vitro.

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In alpacas (Vicugna pacos), the high cost of in vitro embryo production is also a consequence of the use of several substances in the culture medium. In addition, embryo production rates in this species are still considered low. Thus, in attempt to reduce the cost and to improve the in vitro embryo production rates, this study evaluates the effect of adding follicular fluid (FF) in the in vitro maturation medium on oocyte maturation and subsequent embryo production. After ovary collection at the local slaughterhouse, the oocytes were recovered, selected, and allocated in experimental groups: standard maturation medium (G1) and simplified medium added by 10% FF (G2). The FF was acquired from follicles between 7- and 12-mm diameter. The cumulus cell expansion and the embryo production rates were analyzed by chi-square with p < 0.05. No differences (p > 0.05) were observed in maturation rate between G1 (66.36%) and G2 (63.12%) groups. Likewise, no significant difference (p > 0.05) was verified between G1 and G2 for morula (40.85 vs 38.45%), blastocyst (7.01 vs 6.93%), and total number of embryos (47.87 vs 45.38%). In conclusion, it was possible to simplify the medium used for in vitro maturation of alpaca oocytes resulting in embryo production rates similar to the standard medium.

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Depression, as well as other psychosocial factors, remains largely unaddressed among people living with HIV (PLHIV) in low and middle-income countries. Depression is a common occurrence among PLHIV and is elevated in those who consume alcohol. This paper will document the presence of depressive symptoms in alcohol-consuming male PLHIV receiving antiretroviral treatment (ART) in India. It examines the correlates of depressive symptoms and uses the data from in-depth interviews to explain the nature of the statistical relationships obtained from an NIH-funded a multilevel, multi-centric intervention study. A cross-sectional, baseline survey was administered to 940 alcohol consuming, male PLHIV in five hospital-based ART Centers in urban Maharashtra, India via face to face interviews from October 2015 to April 2016. An additional 55 men were recruited independently to engage in in-depth interviews on alcohol use and other factors related to adherence. The results of the survey showed that approximately 38% of PLHIV reported having moderate to severe depressive symptoms. Depressive symptoms were positively associated with higher levels of family-related concerns (OR 1.18; 95% CI 1.12-1.23), work difficulties (OR 2.04; 95% CI 1.69-2.69) and HIV-related self-stigma (OR 1.05; 95% CI 1.03-1.07) and a lower level of ART service satisfaction (OR 0.58 95% CI 0.44-0.77). The results of in-depth interviews showed that PLHIV's tenshun (a Hindi term most closely corresponding to depressive symptoms) resulted from feelings of guilt and concerns about how family, friends, and neighbors might react to their HIV status and the potential for loss of a job as a result of disclosure of their HIV status at work. The level of depressive symptoms among male PLHIV involved in ART treatment points to the need to strengthen the psychological component of PLHIV treatment in India.

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