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In view of the rapidly expanding medical and commercial applications of silver nanoparticles (AgNPs), their potential health risks and environmental effects are a significant growing concern. Earlier research by our group uncovered the embryotoxic potential of AgNPs, showing detrimental impacts of these nanoparticles on both pre- and post-implantation embryonic development. In the current study, we showed that low (50–100 μM) and high (200–400 μM) dose ranges of AgNPs trigger distinct cell death programs affecting mouse embryo development and further explored the underlying mechanisms. Treatment with low concentrations of AgNPs (50–100 μM) triggered ROS generation, in turn, inducing mitochondria-dependent apoptosis, and ultimately, harmful effects on embryo implantation, post-implantation development, and fetal development. Notably, high concentrations of AgNPs (200–400 μM) evoked more high-level ROS generation and endoplasmic reticulum (ER) stress-mediated necrosis. Interestingly, pre-incubation with Trolox, a strong antioxidant, reduced ROS generation in the group treated with 200–400 μM AgNPs to the level induced by 50–100 μM AgNPs, resulting in switching of the cell death mode from necrosis to apoptosis and a significant improvement in the impairment of embryonic development. Our findings additionally indicate that activation of PAK2 is a crucial step in AgNP-triggered apoptosis and sequent detrimental effects on embryonic development. Based on the collective results, we propose that the levels of ROS generated by AgNP treatment of embryos serve as a critical regulator of cell death type, leading to differential degrees of damage to embryo implantation, post-implantation development and fetal development through triggering apoptosis, necrosis or other cell death signaling cascades. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) is a potent toxin that exerts deleterious effects on human health via environmental contamination. Significant effects of MeHg on neuronal development in embryogenesis have been reported. Recently, our group demonstrated that MeHg exerts toxic effects on pre- and post-implantation embryonic development processes from zygote to blastocyst stage. Our results showed that MeHg impairs embryo development by induction of apoptosis through reactive oxygen species (ROS) generation that triggers caspase-3 cleavage and activation, which, in turn, stimulates p21-activated kinase 2 (PAK2) activity. Importantly, ROS were identified as a key upstream regulator of apoptotic events in MeHg-treated blastocysts. Data from the current study further confirmed that MeHg exerts hazardous effects on cell proliferation, apoptosis, implantation, and pre- and post-implantation embryo development. Notably, MeHg-induced injury was markedly prevented by co-culture with adipose-derived mesenchymal stem cells (ADMSCs) in vitro. Furthermore, ADMSC injection significantly reduced MeHg-mediated deleterious effects on embryo, placenta, and fetal development in vivo. Further investigation of the regulatory mechanisms by which co-cultured ADMSCs could prevent MeHg-induced impairment of embryo development revealed that ADMSCs effectively reduced ROS generation and its subsequent downstream apoptotic events, including loss of mitochondrial membrane potential and activation of caspase-3 and PAK2. The collective findings indicate that co-culture with mesenchymal stem cells (MSCs) or utilization of MSC-derived cell-conditioned medium offers an effective potential therapeutic strategy to prevent impairment of embryo development by MeHg. Graphical Abstract [ABSTRACT FROM AUTHOR]

The current study has focused on the effects of enniatin B (ENN B, a major mycotoxin produced by Fusarium fungi) on early embryonic development. In in vitro analysis, mouse blastocysts were incubated in medium with ENN B (0–40 μM) or 0.5% DMSO (control group) for 24 hours. In an animal study, blastocysts were collected from mice which were intravenously injected with ENN B (1, 3, 5, and 7mg/kg body weight/day) for 4 days in order to analyze apoptosis and necrosis via Annexin V/PI staining assay; and proliferation using dual differential staining. Exposure to low ENN B concentration (10 μM in vitro and 3 mg/kg/day in vivo) promoted Reactive Oxygen Species (ROS) generation and apoptosis in the Inner Cell Mass (ICM), the mass of cells inside the blastocyst, impairing post-implantation development alone. On the other hand, exposure to a higher ENN B concentration (40 μM in vitro and 7 mg/kg/day in vivo) induced ROS generation and decreased in intracellular ATP which encouraged necrotic processes in both trophectoderm (TE) and ICM of blastocysts leading to impaired implantation and post-implantation development. Moreover, 5 and 7 mg/kg/day ENN B intraperitoneal injection to female mice for 4 days has caused downregulation of CXCL1, IL-1β and IL-8 expressions and increased ROS generation in the liver of newborn mice. Over all, ENN B can induce apoptosis and/or necrosis depending on the treatment dosage in mouse blastocysts. ENN B-induced necrosis in blastocysts may exert long-term harmful effects on next-generation newborns. [ABSTRACT FROM AUTHOR]

Enniatins are mycotoxins of Fusarium fungi that naturally exist as mixtures of cyclic depsipeptides. Previous reports have documented hazardous effects of enniatins on cells, such as apoptosis. However, their effects on pre‐ and post‐implantation embryonic development require further clarification. Here, we showed for the first time that enniatin B1 (ENN B1) exerts cytotoxic effects on mouse blastocyst‐stage embryos and induces intracellular oxidative stress and immunotoxicity in mouse fetuses. Co‐incubation of blastocysts with ENN B1 triggered significant apoptosis and led to a decrease in total cell number predominantly through loss of inner cell mass. In addition, ENN B1 appeared to exert hazardous effects on pre and postimplantation embryo development potential in an in vitro development assay. Treatment of blastocysts with 1‐10 μM ENN B1 led to increased resorption of post‐implantation embryos and decreased fetal weight in the embryo transfer assay in a dose‐dependent manner. Importantly, in an in vivo model, intravenous injection with ENN B1 (1, 3, and 5 mg/kg body weight/d) for 4 days resulted in apoptosis of blastocyst‐stage embryos and impairment of embryonic development from the zygote to blastocyst stage, subsequent degradation of embryos, and further decrease in fetal weight. Intravenous injection with 5 mg/kg body weight/d ENN B1 additionally induced a significant increase in total reactive oxygen species (ROS) content and transcription levels of genes encoding antioxidant proteins in mouse fetal liver. Moreover, ENN B1 triggered apoptosis through ROS generation and strategies to prevent apoptotic processes effectively rescued ENN B1‐mediated hazardous effects on embryonic development. Transcription levels of CXCL1, IL‐1β, and IL‐8 related to innate immunity were downregulated after intravenous injection of ENN B1. These results collectively highlight the potential of ENN B1 to exert cytotoxic effects on embryos as well as oxidative stress and immunotoxicity during mouse embryo development. [ABSTRACT FROM AUTHOR]

Aim The purpose of the present study was to investigate the injury types and medical utilization profiles of veterans in emergency department visits by using big data from the National Health Insurance program in Taiwan. Method We used the outpatient prescriptions and treatment records between 1997 and 2010 of veterans aged ≥65 years in the National Health Insurance Research Database. The I nternational C lassification of D iseases, N inth R evision, C linical M odification codes 800-999 (i.e. injuries) were selected, and the emergency medical treatment and the medical institutions' basic profile were recorded. Results A total of 287 113 veterans were selected for this study. The average age was 77.4 years, and most participants were men (71.2%). The total medical expenses were US$46.0 million (an average of US$160.00 per person). Contusions/abrasions, open wounds, and fractures comprised 29.2%, 26.6% and 16.3% of the injuries, respectively. In addition, contusions/abrasions, open wounds, and fractures comprised 23.8%, 21.5% and 19.8%, respectively, of the total medical expenses. The highest charges for a single injury episode were for spinal cord and nerve injuries (an average of US$349.00 per person). Regarding sex differences, women mainly experienced fractures and contusions/abrasions, whereas men experienced open wounds. Conclusions The injury rate of veterans was reported higher than the non-veterans. Preventive methods are proposed to decrease the occurrences of injury, number of emergency visits and medical expenses. Geriatr Gerontol Int 2016; 16: 1254-1262. [ABSTRACT FROM AUTHOR]

Optical microscope was used to explore fiber morphology both in the upper and lower sides of one year-old branches among four upright and pendulous varieties by the H2 O2-CH2 COOH maceration.The results were as fol-lowed:the length of fiber in the lower side of the upright branches at the bottom was longer than the upper side sig-nificantly,the length of fiber in the upper side of the pendulous branches at the bottom was longer than the lower side significantly.There were no significant differences in other positions;the fiber diameter at different positions among four varieties indicated no significant differences separately.The results showed that the diferences of fiber size effects shoot development of Prunus mume. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) is a potent toxin that exerts deleterious effects on human health via environmental contamination. Significant effects of MeHg on neuronal development in embryogenesis have been reported. Recently, our group demonstrated that MeHg exerts toxic effects on pre- and post-implantation embryonic development processes from zygote to blastocyst stage. Our results showed that MeHg impairs embryo development by induction of apoptosis through reactive oxygen species (ROS) generation that triggers caspase-3 cleavage and activation, which, in turn, stimulates p21-activated kinase 2 (PAK2) activity. Importantly, ROS were identified as a key upstream regulator of apoptotic events in MeHg-treated blastocysts. Data from the current study further confirmed that MeHg exerts hazardous effects on cell proliferation, apoptosis, implantation, and pre- and post-implantation embryo development. Notably, MeHg-induced injury was markedly prevented by co-culture with adipose-derived mesenchymal stem cells (ADMSCs) in vitro. Furthermore, ADMSC injection significantly reduced MeHg-mediated deleterious effects on embryo, placenta, and fetal development in vivo. Further investigation of the regulatory mechanisms by which co-cultured ADMSCs could prevent MeHg-induced impairment of embryo development revealed that ADMSCs effectively reduced ROS generation and its subsequent downstream apoptotic events, including loss of mitochondrial membrane potential and activation of caspase-3 and PAK2. The collective findings indicate that co-culture with mesenchymal stem cells (MSCs) or utilization of MSC-derived cell-conditioned medium offers an effective potential therapeutic strategy to prevent impairment of embryo development by MeHg., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Under the health-care insurance system in Taiwan, hospital management has not only to challenge the impacts of the post-SARS era, but also has to conquer the system change brought about by the National Health-Insurance Bureau. By global budget and various quality-control indicators, the hospital confronts pressure on restriction measures, including, on the one hand, reducing manpower, while on the other, pushing remaining employees to achieve more. The nursing department, comprising the highest percentage of faculty in the hospital, cannot but burden itself by accepting more duties. A ward nursing unit (WNU) therefore, has taken on the fundamental role of attaining the goals set by the hospital. This review is concerned with how the WNU functions and what kind of relationships exist between head nurses and staff nurses. An approach was adopted of exploring the impact of transactional leadership and trust on Organizational-Citizenship Behavior (OCB) between head nurse and staff nurses, with the aim of clarifying the present situation and proposing some suggestions for future modifications.