RESUMO
Cadmium, an environmental toxicant, severely impairs male reproductive functions and currently lacks effective clinical treatments. Mesenchymal stem cell-derived exosomes (MSC-Exos) are increasingly recognized as a potential alternative to whole-cell therapy for tissue injury and regeneration. This study aims to investigate the protective effects of MSC-Exos against cadmium toxicity on male reproduction. Our findings reveal that MSC-Exos treatment significantly promotes spermatogenesis, improves sperm quality, and reduces germ cell apoptosis in cadmium-exposed mice. Mechanistically, MSC-Exos dramatically mitigate cadmium-induced cell apoptosis in a spermatogonia cell line (GC-1 spg) in vitro by reducing DNA damage and promoting autophagic flux. These results suggest that MSC-Exos have a protective effect on cadmium-induced germ cell apoptosis by ameliorating DNA damage and autophagy flux, demonstrating the therapeutic potential of MSC-Exos for cadmium toxicity on male reproduction.
RESUMO
As testicular mesenchymal stromal cells, stem Leydig cells (SLCs) show great promise in the treatment of male hypogonadism. The therapeutic functions of mesenchymal stromal cells are largely determined by their reciprocal regulation by immune responses. However, the immunoregulatory properties of SLCs remain unclear. Here, we observe that SLCs transplantation restore male fertility and testosterone production in an ischemiaâreperfusion injury mouse model. SLCs prevent inflammatory cascades through mitochondrial transfer to macrophages. Reactive oxygen species (ROS) released from activated macrophages inducing mitochondrial transfer from SLCs to macrophages in a transient receptor potential cation channel subfamily member 7 (TRPM7)-mediated manner. Notably, knockdown of TRPM7 in transplanted SLCs compromised therapeutic outcomes in both testicular ischemiaâreperfusion and testicular aging mouse models. These findings reveal a new mechanism of SLCs transplantation that may contribute to preserve testis function in male patients with hypogonadism related to immune disorders.
Assuntos
Hipogonadismo , Canais de Cátion TRPM , Humanos , Masculino , Camundongos , Animais , Células Intersticiais do Testículo , Testículo/fisiologia , Testosterona , Hipogonadismo/terapia , Macrófagos , Proteínas Serina-Treonina QuinasesRESUMO
An MHD vibration sensor, as a new type of sensor used for vibration measurements, meets the technical requirements for the low-noisy measurement of acceleration, velocity, and micro-vibration in spacecraft during their development, launch, and orbit operations. A linear vibration sensor with a runway type based on MHD was independently developed by a laboratory. In a practical test, its output signal was mixed with a large amount of noise, in which the continuous narrowband interference was particularly prominent, resulting in the inability to efficiently carry out the real-time detection of micro-vibration. Considering the high interference of narrowband noise in linear vibration signals, a single-channel blind signal separation method based on SSA and FastICA is proposed in this study, which provides a new strategy for linear vibration signals. Firstly, the singular spectrum of the linear vibration signal with noise was analyzed to suppress the narrowband interference in the collected signal. Then, a FastICA algorithm was used to separate the independent signal source. The experimental results show that the proposed method can effectively separate the useful linear vibration signals from the collected signals with low SNR, which is suitable for the separation of the MHD linear vibration sensor and other vibration measurement sensors. Compared with EEMD, VMD, and wavelet threshold denoising, the SNR of the separated signal is increased by 10 times on average. Through the verification of the actual acquisition of the linear vibration signal, this method has a good denoising effect.
RESUMO
Introduction: The COVID-19 pandemic affects the process of care transition for patients with underlying chronic conditions. This study aims to explore the impact of the pandemic measures on discharge planning and continuum of care for vulnerable older patients from multi-stakeholder perspectives. Methods: We conducted focus group discussions and individual interviews with healthcare workers, community partners, government officials and family caregivers in Singapore. All interviews were audio-recorded, transcribed verbatim and thematically analysed. Results: A total of 53 individuals participated in the study. Discharge planning and care continuity in the community were affected primarily by the limited step-down care options and remote assessment of discharge needs. Participants felt a need to revisit the decision of 'essential' community services through engagement of all stakeholders to enhance care community.To improve better care transition, participants suggested the need for clearer communication of guidelines, improved intersectoral collaboration, shared responsibility of patient care through community engagement and employment of novel models of care. Conclusion: The pandemic measures generated challenges of safe discharge of patients and care continuity in the community. Findings shed light on the need to proactively assess care pathways and catalyse novel models to improve care transition beyond the pandemic.