The effects of repeated freezing and thawing on bovine sperm morphometry and function.

Refreezing the remaining genetic resources after in vitro fertilization (IVF) can conserve genetic materials. However, the precise damage inflicted by repeated freezing and thawing on bovine sperm and its underlying mechanism remain largely unexplored. Thus, this study investigates the impact of repeated freeze-thaw cycles on sperm. Our findings indicate that such cycles significantly reduce sperm viability and motility. Furthermore, the integrity of the sperm plasma membrane and acrosome is compromised during this process, exacerbating the advanced apoptosis triggered by oxidative stress. Additionally, transmission electron microscopy exposed severe damage to the plasma membranes of both the sperm head and tail. Notably, the "9 + 2" structure of the tail was disrupted, along with a significant decrease in the level of the axonemal protein DNAH10, leading to reduced sperm motility. IVF outcomes revealed that repeated freeze-thaw cycles considerably impair sperm fertilization capability, ultimately reducing the blastocyst rate. In summary, our research demonstrates that repeated freeze-thaw cycles lead to a decline in sperm viability and motility, attributed to oxidative stress-induced apoptosis and DNAH10-related dynamic deficiency. As a result, the utility of semen is compromised after repeated freezing.

Genome-wide identification of Brassicaceae histone modification genes and their responses to abiotic stresses in allotetraploid rapeseed.

BACKGROUND: Histone modification is an important epigenetic regulatory mechanism and essential for stress adaptation in plants. However, systematic analysis of histone modification genes (HMs) in Brassicaceae species is lacking, and their roles in response to abiotic stress have not yet been identified. RESULTS: In this study, we identified 102 AtHMs, 280 BnaHMs, 251 BcHMs, 251 BjHMs, 144 BnHMs, 155 BoHMs, 137 BrHMs, 122 CrHMs, and 356 CsHMs in nine Brassicaceae species, respectively. Their chromosomal locations, protein/gene structures, phylogenetic trees, and syntenies were determined. Specific domains were identified in several Brassicaceae HMs, indicating an association with diverse functions. Syntenic analysis showed that the expansion of Brassicaceae HMs may be due to segmental and whole-genome duplications. Nine key BnaHMs in allotetraploid rapeseed may be responsible for ammonium, salt, boron, cadmium, nitrate, and potassium stress based on co-expression network analysis. According to weighted gene co-expression network analysis (WGCNA), 12 BnaHMs were associated with stress adaptation. Among the above genes, BnaPRMT11 simultaneously responded to four different stresses based on differential expression analysis, while BnaSDG46, BnaHDT10, and BnaHDA1 participated in five stresses. BnaSDG46 was also involved in four different stresses based on WGCNA, while BnaSDG10 and BnaJMJ58 were differentially expressed in response to six different stresses. In summary, six candidate genes for stress resistance (BnaPRMT11, BnaSDG46, BnaSDG10, BnaJMJ58, BnaHDT10, and BnaHDA1) were identified. CONCLUSIONS: Taken together, these findings help clarify the biological roles of Brassicaceae HMs. The identified candidate genes provide an important reference for the potential development of stress-tolerant oilseed plants.

Tetrabromobisphenol Exposure Impairs Bovine Oocyte Maturation by Inducing Mitochondrial Dysfunction.

Tetrabromobisphenol (TBBPA) is the most widely used brominated flame retardant in the world and displays toxicity to humans and animals. However, few studies have focused on its impact on oocyte maturation. Here, TBBPA was added to the culture medium of bovine cumulus-oocyte complexes (COCs) to examine its effect on oocytes. We found that TBBPA exposure displayed an adverse influence on oocyte maturation and subsequent embryonic development. The results of this study showed that TBBPA exposure induced oocyte meiotic failure by disturbing the polar-body extrusion of oocytes and the expansion of cumulus cells. We further found that TBBPA exposure led to defective spindle assembly and chromosome alignment. Meanwhile, TBBPA induced oxidative stress and early apoptosis by mediating the expression of superoxide dismutase 2 (SOD2). TBBPA exposure also caused mitochondrial dysfunction, displaying a decrease in mitochondrial membrane potential, mitochondrial content, mtDNA copy number, and ATP levels, which are regulated by the expression of pyruvate dehydrogenase kinase 3 (PDK3). In addition, the developmental competence of oocytes and the quality of blastocysts were also reduced after TBBPA treatment. These results demonstrated that TBBPA exposure impaired oocyte maturation and developmental competence by disrupting both nuclear and cytoplasmic maturation of the oocyte, which might have been caused by oxidative stress induced by mitochondrial dysfunction.

A novel transurethral resection technique for superficial bladder tumor: retrograde en bloc resection.

BACKGROUND: Transurethral resection of bladder tumor (TURBT) is the standard approach to bladder tumors but suffers from several disadvantages. The aim of this study was to evaluate the safety and efficacy of a novel procedure of retrograde en bloc resection of bladder tumor (RERBT) with conventional monopolar resection electrode for the treatment of superficial bladder tumors. METHODS: RERBT and conventional TURBT (C-TURBT) were conducted, respectively, in 40 and 50 patients diagnosed with superficial papillary bladder tumors. In the RERBT group, the tumors were en bloc removed retrogradely under direct vision using a conventional monopolar electrode. Patients' clinicopathological, intraoperative, and postoperative data were compared retrospectively between the RERBT and C-TURBT groups. RESULTS: Of the 90 patients, 40 underwent RERBT and 50 underwent C-TURBT. Both groups were comparable in clinicopathological characteristic. RERBT could be performed as safely and effectively as C-TURBT. There were no significant differences in operative time and surgical complications. The cumulative recurrence rates between groups were similar during up to 18 months follow-up. The detrusor muscle could be identified pathologically in 100% of RERBT tumor specimens and the biopsy of tumor bases, but only in 54 and 70%, respectively, of C-TURBT samples (P < 0.01). CONCLUSIONS: The RERBT technique is feasible and safe for superficial bladder tumors using conventional monopolar resection setting, with the advantages of adequate tumor resection and the ability to collect good quality tumor specimens for pathological diagnosis and staging compared to conventional TURBT.

Carboxymethyl chitosan/polyvinyl alcohol double network hydrogels prepared by freeze-thawing and calcium chloride cross-linking for efficient dye adsorption.

The discharge of dye wastewater resulting from rapid industrial development has become a serious environmental concern. Therefore, there is a pressing need to develop efficient methods and technologies for the removal of dye pollutants. This study introduced a double network hydrogel, with varying carboxymethyl chitosan (CMCS) contents and polyvinyl alcohol (PVA), employing a combination of freeze- thawing and calcium chloride cross-linking. The investigation focused on the rheological properties of the hydrogels and their removal ability of acidic blue 93 (AB). The results showed that the strength and viscoelastic modulus of composite hydrogels were positively correlated with the CMCS content, and all composite hydrogels exhibited the typical weak strain overshoot behavior. The pore size of the gel initially decreased and then increased, with the densest pores observed at 4 wt% CMCS, showing the optimal removal ability for AB. The adsorption process followed pseudo second-order kinetic model, dominated by external diffusion, and exhibited inhomogeneous multilayer adsorption. This study unveils the potential of CMCS/PVA gels as adsorbents, offering inspirations for the design and development of polyvinyl alcohol-based gels for applications in the food industry.

ß-hydroxybutyrate impairs bovine oocyte maturation via pyruvate dehydrogenase (PDH) associated energy metabolism abnormality.

Background: Ketosis is one of the most frequent and costly metabolic disorders in high-producing dairy cows, and negatively associated with the health and reproductive performance of bovine. Ketosis is mainly caused by the accumulation of ketone body ß-hydroxybutyric acid and its diagnosis is based on ß-hydroxybutyrate (ßHB) concentration in blood. Methods: In this study, we investigated the effects of ßHB on bovine oocyte maturation in the concentration of subclinical (1.2 mM) ßHB and clinical (3.6 mM). Results: The results showed ßHB disrupted bovine oocyte maturation and development capacity. Further analysis showed that ßHB induced oxidative stress and mitochondrial dysfunction, as indicated by the increased level of reactive oxygen species (ROS), disrupted mitochondrial structure and distribution, and depolarized membrane potential. Furthermore, oxidative stress triggered early apoptosis, as shown by the enhanced levels of Caspase-3 and Annexin-V. Moreover, 3.6 mM ßHB induced the disruption of the pyruvate dehydrogenase (PDH) activity, showing with the decrease of the global acetylation modification and the increase of the abnormal spindle rate. Conclusion: Our study showed that ßHB in subclinical/clinical concentration had toxic effects on mitochondrial function and PDH activity, which might affect energy metabolism and epigenetic modification of bovine oocytes and embryos.

Aldosterone-to-renin ratio acts as the predictor distinguishing the primary aldosteronism from chronic kidney disease.

Aldosterone-to-renin ratio (ARR) is a screening test for primary aldosteronism, but it was impacted by a bunch of clinical covariates. The ARR is associated with chronic kidney disease (CKD), renal artery stenosis, renin adenoma. This study aims to investigate relationship between ARR and primary aldosteronism in CKD patients. A retrospective observational analysis involves 253 attendees from Urology Department of Chengdu Military General Hospital (China), comprising 146 patients with confirmed primary aldosteronism, 56 patients with essential hypertension, and 55 patients with chronic kidney disease accounting for primary kidney disease. Blood samples were drawn from patients with particular restriction for measuring serum aldosteronism, plasma renin activity, and serum potassium. Receiver operating characteristic (ROC) curve of ARR was tested to establish cutoff values and to assess sensitivity and specificity. The results showed that LogARR values were significantly higher (P < 0.001), and PRA and serum potassium values were significantly lower (P < 0.001) in primary aldosteronism patients. By contrast, significantly higher serum aldosterone and plasma renin were observed in CKDs compared with the other two groups (P < 0.001). There was a significantly positive correlation between LogARR and serum potassium (r = -0.0345, P < 0.001, R(2) = 0.093). The AUC for plasma renin activity, logARR, and serum aldosterone are 0.855, 0.84, and 0.501, respectively. ROC curve of logARR and plasma renin activity in detection of primary aldosteronism with higher sensitivity and specificity. In conclusion, this study indicated that the ARR act as the biomarker for the primary aldosteronism, and could distinguish from chronic kidney disease.

Hydrogen sulfide inhibits formaldehyde-induced endoplasmic reticulum stress in PC12 cells by upregulation of SIRT-1.

BACKGROUND: Formaldehyde (FA), a well-known environmental pollutant, has been classified as a neurotoxic molecule. Our recent data demonstrate that hydrogen sulfide (H2S), the third gaseous transmitter, has a protective effect on the neurotoxicity of FA. However, the exact mechanisms underlying this protection remain largely unknown. Endoplasmic reticulum (ER) stress has been implicated in the neurotoxicity of FA. Silent mating type information regulator 2 homolog 1 (SIRT-1), a histone deacetylases, has various biological activities, including the extension of lifespan, the modulation of ER stress, and the neuroprotective action. OBJECTIVE: We hypothesize that the protection of H2S against FA-induced neurotoxicity involves in inhibiting ER stress by upregulation of SIRT-1. The present study attempted to investigate the protective effect of H2S on FA-induced ER stress in PC12 cells and the contribution of SIRT-1 to the protection of H2S against FA-induced injuries, including ER stress, cytotoxicity and apoptosis. PRINCIPAL FINDINGS: We found that exogenous application of sodium hydrosulfide (NaHS; an H2S donor) significantly attenuated FA-induced ER stress responses, including the upregulated levels of glucose-regulated protein 78, C/EBP homologous protein, and cleaved caspase-12 expression. We showed that NaHS upregulates the expression of SIRT-1 in PC12 cells. Moreover, the protective effects of H2S on FA-elicited ER stress, cytotoxicity and apoptosis were reversed by Sirtinol, a specific inhibitor of SIRT-1. CONCLUSION/SIGNIFICANCE: These data indicate that H2S exerts its protection against the neurotoxicity of FA through overcoming ER stress via upregulation of SIRT-1. Our findings provide novel insights into the protective mechanisms of H2S against FA-induced neurotoxicity.