This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Investigated the mechanisms by which baicalein regulates nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)to ameliorate lipopolysaccharide(LPS)-induced sepsis-asso-ciated acute kidney injury(AKI)in mice.Sixty male C57BL/6 mice were randomly divided into six groups:control,model,low-dose baicalein(50 mg/kg),medium-dose baicalein(100 mg/kg),high-dose baicalein(200 mg/kg),and high-dose baicalein+brusatol(4 mg/kg).Baicalein was adminis-tered orally for 7 days as a preventative measure.Sepsis was induced via intraperitoneal injection of LPS.Murine sepsis score(MSS)was assessed within 12 hours post-induction.Serum creatinine(Scr),blood urea nitrogen(BUN),tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),and interleukin-6(IL-6)were measured using an automatic biochemical analyzer and enzyme-linked immunosorbent assays(ELISA),respectively.Histopathological changes in kidney tissues were ob-served via hematoxylin-eosin(HE)staining.Western blot analysis was employed to determine the protein expression levels of Nrf2,HO-1,caspase-8,TNF-α,IL-1β,and IL-6 in kidney tissues.Additionally,total superoxide dismutase(SOD)activity in kidney tissues was assessed using com-mercially available kits.Compared to the model group,baicalein treatment significantly improved renal histopathological changes,alleviated cellular damage,and reduced the levels of inflammatory cytokines(TNF-α,IL-1βand IL-6)(P＜0.01)and kidney injury markers(Scr and BUN)(P＜0.01).Moreover,baicalein treatment significantly increased the protein expression levels of Nrf2 and HO-1(P＜0.01)and enhanced antioxidant enzyme activity.In conclusion,baicalein may pro-tect against LPS-induced sepsis-associated AK1 in mice by modulating the Nrf2/HO-1 signaling pathway,thereby attenuating oxidative stress,reducing inflammation,and disrupting the vicious cycle between inflammation and oxidative stress.

Objective:To investigate the role of platelet-derived zyxin in promoting tumor migration by platelets.Methods:The gene expression profile of platelets was analyzed from cancer patients by using the GEO database.Isolated platelets from wild-type(WT)and Zyx-/-mice were co-cultured with B16F10 cells labeled with green fluorescence to investigate the influence of zyxin deficiency on tumor cell migration,invasion,and wound healing.Optical microscopy was employed to evaluate the impact of zyxin deficiency on epithelial-mesenchymal transition(EMT)in B16F10 cells induced by platelets.Employing specific markers to label platelets,fluorescence confocal microscopy was utilized to investigate the impact of platelet-derived zyxin on the binding between tumor cells and platelets.And an aggregometer was employed to observe the influence of zyxin deficiency on tumor cell-induced platelet aggregation.Results:Compared to platelets from healthy volunteers,zyxin was upregulated in platelets from cancer patients.Zyx-/-mouse platelets exhibited a significant reduction in tumor cell invasion and migration,impaired wound healing,and delayed tumor cell EMT compared to WT mouse platelets.Additionally,zyxin deficiency attenuated the interaction between platelets and tumor cells,and diminished the capacity for tumor cell-induced platelet aggregation.Conclusion:Platelet-derived zyxin deficiency diminishes platelet-tumor cell interactions and weakens the ability of tumor cell-induced platelet aggregation,ultimately suppressing tumor cell migration.

This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Investigated the mechanisms by which baicalein regulates nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)to ameliorate lipopolysaccharide(LPS)-induced sepsis-asso-ciated acute kidney injury(AKI)in mice.Sixty male C57BL/6 mice were randomly divided into six groups:control,model,low-dose baicalein(50 mg/kg),medium-dose baicalein(100 mg/kg),high-dose baicalein(200 mg/kg),and high-dose baicalein+brusatol(4 mg/kg).Baicalein was adminis-tered orally for 7 days as a preventative measure.Sepsis was induced via intraperitoneal injection of LPS.Murine sepsis score(MSS)was assessed within 12 hours post-induction.Serum creatinine(Scr),blood urea nitrogen(BUN),tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),and interleukin-6(IL-6)were measured using an automatic biochemical analyzer and enzyme-linked immunosorbent assays(ELISA),respectively.Histopathological changes in kidney tissues were ob-served via hematoxylin-eosin(HE)staining.Western blot analysis was employed to determine the protein expression levels of Nrf2,HO-1,caspase-8,TNF-α,IL-1β,and IL-6 in kidney tissues.Additionally,total superoxide dismutase(SOD)activity in kidney tissues was assessed using com-mercially available kits.Compared to the model group,baicalein treatment significantly improved renal histopathological changes,alleviated cellular damage,and reduced the levels of inflammatory cytokines(TNF-α,IL-1βand IL-6)(P＜0.01)and kidney injury markers(Scr and BUN)(P＜0.01).Moreover,baicalein treatment significantly increased the protein expression levels of Nrf2 and HO-1(P＜0.01)and enhanced antioxidant enzyme activity.In conclusion,baicalein may pro-tect against LPS-induced sepsis-associated AK1 in mice by modulating the Nrf2/HO-1 signaling pathway,thereby attenuating oxidative stress,reducing inflammation,and disrupting the vicious cycle between inflammation and oxidative stress.

This study explores whether the current external quality assessment (EQA) level and acceptable bias for basic semen analysis in China are clinically useful. We collected data of semen EQA from Andrology laboratories in the Hunan Province (China) in 2022 and searched for data in the published literature from January 2000 to December 2023 in China. On the basis of these data, we analyzed the coefficients of variation and acceptable biases of different quality control materials for basic semen analysis through robust statistics. We compared these findings with quality specifications based on biological variation from optimal, desirable, and minimum levels of bias to seek a unified and more suitable semen EQA bias evaluation standard for China's national conditions. Different sources of semen quality control material exhibited considerable variation in acceptable biases among laboratories, ranging from 8.2% to 56.9%. A total of 50.0% of the laboratories met the minimum quality specifications for progressive motility (PR), whereas 100.0% and 75.0% of laboratories met only the minimum quality specifications for sperm concentration and total motility (nonprogressive [NP] + PR), respectively. The Z value for sperm concentration and PR+NP was equivalent to the desirable performance specification, whereas the Z value for PR was equivalent only to the minimum performance specification. This study highlights the feasibility of operating external quality assessment schemes for basic semen analysis using quality specifications based on biological variation. These specifications should be unified among external quality control (EQC) centers based on biological variation.
Semen Analysis/standards* ; Humans ; China ; Male ; Quality Control ; Sperm Motility ; Sperm Count/standards*

OBJECTIVE: To explore and quantify the association of hot night exposure during the sperm development period (0-90 lag days) with semen quality. METHODS: A total of 6,640 male sperm donors from 6 human sperm banks in China during 2014-2020 were recruited in this multicenter study. Two indices (i.e., hot night excess [HNE] and hot night duration [HND]) were used to estimate the heat intensity and duration during nighttime. Linear mixed models were used to examine the association between hot nights and semen quality parameters. RESULTS: The exposure-response relationship revealed that HNE and HND during 0-90 days before semen collection had a significantly inverse association with sperm motility. Specifically, a 1 °C increase in HNE was associated with decreased sperm progressive motility of 0.0090 (95% confidence interval [ CI]: -0.0147, -0.0033) and decreased total motility of 0.0094 (95% CI: -0.0160, -0.0029). HND was significantly associated with reduced sperm progressive motility and total motility of 0.0021 (95% CI: -0.0040, -0.0003) and 0.0023 (95% CI: -0.0043, -0.0002), respectively. Consistent results were observed at different temperature thresholds on hot nights. CONCLUSION Our findings highlight the need to mitigate nocturnal heat exposure during spermatogenesis to maintain optimal semen quality.
Humans ; Male ; Semen Analysis ; Adult ; Sperm Motility ; Hot Temperature/adverse effects* ; China ; Middle Aged ; Spermatozoa/physiology* ; Young Adult

BACKGROUND: Our understanding of the correlation between postdischarge cancer and mortality in patients with coronary artery disease (CAD) remains incomplete. The aim of this study was to investigate the relationships between postdischarge cancers and all-cause mortality and cardiovascular mortality in CAD patients. METHODS: In this retrospective cohort study, 25% of CAD patients without prior cancer history who underwent coronary artery angiography between January 1, 2011 and December 31, 2015, were randomly enrolled using SPSS 26.0. Patients were monitored for the incidence of postdischarge cancer, which was defined as cancer diagnosed after the index hospitalization, survival status and cause of death. Cox regression analysis was used to explore the association between postdischarge cancer and all-cause mortality and cardiovascular mortality in CAD patients. RESULTS: A total of 4085 patients were included in the final analysis. During a median follow-up period of 8 years, 174 patients (4.3%) developed postdischarge cancer, and 343 patients (8.4%) died. A total of 173 patients died from cardiovascular diseases. Postdischarge cancer was associated with increased all-cause mortality risk (HR = 2.653, 95% CI: 1.727-4.076, P < 0.001) and cardiovascular mortality risk (HR = 2.756, 95% CI: 1.470-5.167, P = 0.002). Postdischarge lung cancer (HR = 5.497, 95% CI: 2.922-10.343, P < 0.001) and gastrointestinal cancer (HR = 1.984, 95% CI: 1.049-3.750, P = 0.035) were associated with all-cause mortality in CAD patients. Postdischarge lung cancer was significantly associated with cardiovascular death in CAD patients (HR = 4.979, 95% CI: 2.114-11.728, P < 0.001), and cardiovascular death was not significantly correlated with gastrointestinal cancer or other types of cancer. CONCLUSIONS Postdischarge cancer was associated with all-cause mortality and cardiovascular mortality in CAD patients. Compared with other cancers, postdischarge lung cancer had a more significant effect on all-cause mortality and cardiovascular mortality in CAD patients.

Objective:To explore the feasibility of the multiple-choice auditory graphical interactive check（MAGIC） screening module in childhood hearing screening in children aged 3 to 6 years. Methods:A hearing screening was conducted on 366 children（732 ears） aged between 3 and 6 years. The screening methods included MAGIC, DPOAE, and acoustic immittance.The cooperation, screening time, pass rate, and correlation of the three screening methods were compared. Results:There was a statistically significant difference in the degree of cooperation among the three screeningmethods（P=0.004）.The MAGIC pure tone screening method was 98.6%, the screening DPOAE was 99.5%,and the acoustic immittance screening was 100%. For the screening duration, the MAGIC pure tone screening method was（116.3±59.1）s, the screening DPOAE was（27.2±19.7）s, and the acoustic impedance screening was（24.6±14.6）s. There was a significant statistical significance differences among the three or two groups（P<0.01）. The passing rates of MAGIC pure tone screening,screening DPOAE and acoustic immittance screening were 64.7%, 65.4%, and 69.3%, respectively, and there was no significant statistical difference among the three or two groups（P>0.05）. There was no significant difference between MAGIC pure tone screening method and screening DPOAE（P=0.827>0.05）, and acoustic impedance（P=0.653>0.05）, while the difference between screening DPOAE and acoustic impedance was statistically significant（P<0.01）. Conclusion:MAGIC pure sound screening method has good feasibility, can comprehensively reflect the hearing level of screened children, and can be promoted for hearing screening in children aged between 3 and 6 years.
Humans ; Child, Preschool ; Child ; Female ; Male ; Audiometry, Pure-Tone ; Mass Screening/methods* ; Feasibility Studies ; Acoustic Impedance Tests/methods* ; Hearing Loss/diagnosis* ; Hearing Tests/methods*

Glutamine provides carbon and nitrogen to support the proliferation of cancer cells. However, the precise reason why cancer cells are particularly dependent on glutamine remains unclear. In this study, we report that glutamine modulates the tumor suppressor F-box and WD repeat domain-containing 7 (FBW7) to promote cancer cell proliferation and survival. Specifically, lysine 604 (K604) in the sixth of the 7 substrate-recruiting WD repeats of FBW7 undergoes glutaminylation (Gln-K604) by glutaminyl tRNA synthetase. Gln-K604 inhibits SCFFBW7-mediated degradation of c-Myc and Mcl-1, enhances glutamine utilization, and stimulates nucleotide and DNA biosynthesis through the activation of c-Myc. Additionally, Gln-K604 promotes resistance to apoptosis by activating Mcl-1. In contrast, SIRT1 deglutaminylates Gln-K604, thereby reversing its effects. Cancer cells lacking Gln-K604 exhibit overexpression of c-Myc and Mcl-1 and display resistance to chemotherapy-induced apoptosis. Silencing both c-MYC and MCL-1 in these cells sensitizes them to chemotherapy. These findings indicate that the glutamine-mediated signal via Gln-K604 is a key driver of cancer progression and suggest potential strategies for targeted cancer therapies based on varying Gln-K604 status.
Glutamine/metabolism* ; Myeloid Cell Leukemia Sequence 1 Protein/genetics* ; Humans ; Proto-Oncogene Proteins c-myc/genetics* ; Cell Proliferation ; Signal Transduction ; Neoplasms/pathology* ; F-Box-WD Repeat-Containing Protein 7/genetics* ; Cell Survival ; Cell Line, Tumor ; Apoptosis