S-methyl-L-cysteine sulfoxide (SMCO) is a non-protein sulfur-containing amino acid with a variety of functions. There are few reports on the enzymes catalyzing the biosynthesis of SMCO from S-methyl-L-cysteine (SMC). In this study, the flavin-containing monooxygenase gene derived from Schizosaccharomyces pombe (spfmo) was heterologously expressed in Escherichia coli BL21(DE3) and the enzymatic properties of the expressed protein were analyzed. The optimum catalytic conditions of the recombinant SpFMO were 30 ℃ and pH 8.0, under which the enzyme activity reached 72.77 U/g. An appropriate amount of Mg²⁺ improved the enzyme activity. The enzyme kinetic analysis showed that the K_m and k_cat/K_m of SpFMO on the substrate SMC were 23.89 μmol/L and 61.71 L/(min·mmol), respectively. Under the optimal reaction conditions, the yield of SMCO synthesized from SMC catalyzed by SpFMO was 12.31% within 9 h. This study provides reference for the enzymatic synthesis of SMCO.
Schizosaccharomyces/genetics* ; Escherichia coli/metabolism* ; Recombinant Proteins/metabolism* ; Cysteine/biosynthesis* ; Mixed Function Oxygenases/metabolism* ; Schizosaccharomyces pombe Proteins/metabolism* ; Oxygenases/metabolism* ; Kinetics

Objective To explore the potential role and underlying mechanism of the functionally uncharacterized gene Gm49394 on regulating β-cell apoptosis under diabetic conditions.Methods The expression and translational activity of Gm49394 in pancreatic β-cell lines and non-β-cell lines were validated using RNA fluorescence in situ hybridization(RNA-FISH),quantitative real-time PCR(qPCR),Western blotting,and immunofluorescence(IF)assay.The β-cell lines(NIT-1/Min6)with Gm49394 overexpression or knockdown were constructed.The proliferation,apoptosis,mitochondrial function,as well as oxidative stress and endoplasmic reticulum stress markers in these β-cell lines under physiological homeostasis or pathological stress conditions,such as high glucose(30 mmol/L),inflammation(10 ng/mL IFN-γ alone or combined with 10 ng/mL IL-6),and hydrogen peroxide(100 μmol/L H2O2)were detected by flow cytometry and Western blotting.Results RNA-FISH and qPCR indicated that Gm49394 was specifically expressed in pancreatic β-cell lines and up-regulated under high glucose or inflammatory stimulation.IF assay and Western blotting showed that Gm49394 had protein-coding activity.Flow cytometry and Western blotting identified that Gm49394 overexpression did not affect β-cell proliferation,but promoted β-cell apoptosis and increased reactive oxygen species(ROS)and mitochondrial superoxide(MitoSOX)levels in β cells under physiological homeostasis or pathological stress conditions(P<0.05).Under physiological conditions,Gm49394 knockdown failed to induce significant alterations on β-cell apoptosis,ROS,or MitoSOX levels.Under pathological stress conditions,Gm49394 knockdown significantly suppressed β-cell proliferation,apoptosis,as well as oxidative and endoplasmic reticulum stress(P<0.05).Conclusion Gm49394 may promote β-cell apoptosis via oxidative stress and endoplasmic reticulum stress.

Objective To investigate the expression of Cyclin O(CCNO)in cervical cancer and its molecular mechanism in the progression of cervical cancer.Methods The pathological sections of 60 patients with cervical cancer in the Department of Oncology and Gynecology of the First Affiliated Hospital of Bengbu Medical University from January 2018 to December 2023 were collected,and the expression of CCNO in cervical cancer was detected by immunohistochemistry.The cells were divided into Vector group,CCNO group,siNC group and siCCNO group by transfection technology.CCK-8 assay and colony formation assay were used to evaluate the ability of CCNO to affect cell proliferation.Transwell assay and wound healing assay were used to evaluate the effect of CCNO on cell invasion and migration.Glycolysis assay and Western blot assay were used to evaluate the effect and mechanism of CCNO on glycolysis of cervical cancer cells.Results The results of immunohistochemistry and WB showed that CCNO was highly expressed in cervical cancer(P<0.001).Overexpression of CCNO promoted the proliferation,invasion,migration and glycolysis of cervical cancer cells(P<0.05),whereas the opposite effect inhibited the proliferation,invasion,migration and glycolysis of cervical cancer cells(P<0.05).Bioinformatics analysis and WB results showed that CCNO overexpression may regulate the occurrence of cervical cancer by activating the PI3K/AKT signaling pathway(P<0.05).Conclusion Cyclin O may promote the proliferation and metastasis of cervical cancer cells by regulating glycolysis.

At present, the major public health challenges caused by novel coronavirus infection have gradually subside. However, a large number of people are still suffering from long-novel coronavirus syndrome or post-novel coronavirus syndrome. The clinical manifestations of long coronavirus syndrome are related to multiple systems, such as respiratory, circulatory, nervous, digestive and musculoskeletal systems, with various long-term persistent symptoms after novel coronavirus infection. At the same time, the infection of the novel coronavirus is an important cause of frailty and sarcopenia in the elderly population. However, at present, the scholars have not paid enough attention to the skeletal muscle weakness caused by the novel coronavirus. Therefore, this paper focuses on the long-novel coronavirus syndrome and sarcopenia to explore the pathological mechanism of skeletal muscle attenuation caused by the SARS-CoV-2 mediated "cytokine storm", mitochondrial damage, hypoxia state and other links, so as to raise the attention of clinical and academic researchers and improve the clinical strategy of frailty and sarcopenia after novel coronavirus infection.

ObjectivesTo compare the clinical efficacy and complications of anatomic locking titanium plate （hereinafter referred to as “titanium plate screw”） and intramedullary nail in the treatment of distal tibial fractures.Methods From September 2019 to September 2021， 32 patients diagnosed with AO-A fracture of distal tibia at Sun Yat-sen Memorial Hospital of Sun Yat-sen University were included in this study. Of these， 15 cases were treated with titanium plate screws and 17 cases were treated with intramedullary nails. General surgical indexes， fracture healing time and postoperative operation were compared between the two groups.ResultsAll patients were followed up for 10 to 20 months， with an average of 12 months. The operative time and intraoperative fluoroscopy times of intramedullary nail group were longer than those of titanium plate screw group， but the preoperative waiting time and hospitalization days was less or were fewer than those of titanium plate screw group， the difference was statistically significant （P < 0.05）. There was no significant difference in fracture healing time between the two groups （P> 0.05）. At 6 weeks after operation， VAS scores in both groups were lower than those before operation， with statistically significant difference （P<0.05）. There was no significant difference in VAS scores between the intramedullary nail group and the titanium plate screw group （P> 0.05）. AOFAS scores 6 months after surgery， ankle joint motion and complication rate 1 year after surgery in intramedullary screw group were better than those in titanium plate screw group， and the differences were statistically significant （P< 0.05）. There was no significant difference in AOFAS scores between the two groups at 1 year after operation （P> 0.05）.ConclusionTitanium plate screw and intramedullary nail are both effective methods for the treatment of distal tibial AO-A fracture， and there is no significant difference in long-term clinical efficacy. Intramedullary nail has fewer soft tissue complications， less impact on ankle motion， faster recovery and higher safety， while titanium plate screw has a higher probability of postoperative soft tissue infection. We suggest that in clinical work， preoperative evaluation of patients should be done well. Under the premise of grasping the indications， intramedullary nail has fewer complications and certain advantages.

AIM: To investigate the effect of scleral-fixated capsular tension ring(SFCTR)combined with phacoemulsification and intraocular lens(IOL)implantation in the treatment of traumatic lens subluxation.METHODS: A total of 14 patients(14 eyes)who underwent SFCTR combined with phacoemulsification and IOL implantation for traumatic lens subluxation from December 2018 to February 2023 were selected. Visual acuity, intraocular pressure, anterior segment photography, and ultrasound biomicroscopy(UBM)were examined during postoperative follow-up. The location of IOL and postoperative complications were recorded.RESULTS: SFCTRs and IOLs were successfully implanted in all patients. The mean postoperative follow-up was 1.92±1.36 a. At the last follow-up, the uncorrected distance visual acuity(UDVA; 0.20±0.18 LogMAR)and corrected distance visual acuity(CDVA; 0.16±0.17 LogMAR)were significantly improved compared with the UDVA(1.13±0.56 LogMAR)preoperatively(P<0.01). The intraocular pressure(17.64±3.67 mmHg)was lower than that before the operation(22.00±9.92 mmHg; P<0.05). During the follow-up, the slit-lamp examination showed that the IOL was in the middle of the pouch. UBM examination showed that the CTR and IOL were located in the pouch, and the distance between the equatorial part of the pouch and the ciliary process was equal in all directions.CONCLUSION: The SFCTR combined with phacoemulsification and IOL implantation is an efficient and minimally invasive method in the treatment of traumatic lens subluxation.

Objective To compare and analyze the differences in CD8+naive,effector,memory,exhausted and regulatory T cells in order to investigate the impact of gender on the differentiation fate of CD8+T cells in the context of type 1 diabetes (T1D)based on female and male non-obese diabetic (NOD)mice and healthy Institute for Cancer Research (ICR)mice.Methods The frequencies and phenotypes of CD8+T cell differentiation subsets including naive T cells (TN),central memory T cells (TCM),effector T cells(TEFF),effector precursor T cells (TEP),exhausted T cells (TEX),precursor exhausted T cells (TPEX)and regulatory T cells (Tregs)in the spleen,pancreatic draining lymph nodes (pLN)and pancreas infiltrating lymphocytes (PIL)of male and female NOD mice were detected by flow cytometry.Results The frequencies of IFN-γ+,CD107a+and CCL5+CD8+TEFF in pLN and PIL of female NOD mice were significantly higher than those of male NOD mice.However,the frequencies of CD8+TN,CD8+TCM,CD8+TEX,CD8+TPEX and CD122+CD8+Tregs subsets in the spleen were significantly decreased.While there were no significant differences in the above CD8+T cell subsets except CD8+Tregs between female and male ICR mice. Conclusion Androgen may inhibit the differentiation of memory T cells into effector T cells and promote the exhaustion of effector T cells,leading to the difference in morbidity between the male and female mice.

Uncovering the risk factors of pulmonary hypertension and its mechanisms is crucial for the prevention and treatment of the disease.In the current study,we showed that experimental periodontitis,which was established by ligation of molars followed by orally smearing subgingival plaques from patients with periodontitis,exacerbated hypoxia-induced pulmonary hypertension in mice.Mechanistically,periodontitis dysregulated the pulmonary microbiota by promoting ectopic colonization and enrichment of oral bacteria in the lungs,contributing to pulmonary infiltration of interferon gamma positive(IFNγ+)T cells and aggravating the progression of pulmonary hypertension.In addition,we identified Prevotella zoogleoformans as the critical periodontitis-associated bacterium driving the exacerbation of pulmonary hypertension by periodontitis,and the exacerbation was potently ameliorated by both cervical lymph node excision and IFNγ neutralizing antibodies.Our study suggests a proof of concept that the combined prevention and treatment of periodontitis and pulmonary hypertension are necessary.

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) for the prenatal diagnosis of chromosomal mosaicisms. METHODS: A total of 775 pregnant women who had visited the Prenatal Diagnosis Center of Yancheng Maternal and Child Health Care Hospital from January 2018 to December 2020 were selected as study subjects. Chromosome karyotyping analysis and CMA were carried out for all women, and FISH was used to validate the suspected mosaicism cases. RESULTS: Among the 775 amniotic fluid samples, karyotyping has identified 13 mosaicism cases, which yielded a detection rate of 1.55%. Respectively, there were 4, 3, 4 and 2 cases for sex chromosome number mosaicisms, abnormal sex chromosome structure mosaicisms, abnormal autosomal number mosaicisms and abnormal autosomal structure mosaicisms. CMA has only detected only 6 of the 13 cases. Among 3 cases verified by FISH, 2 cases were consistent with the karyotyping and CMA results, and clearly showed low proportion mosaicism, and 1 case was consistent with the result of karyotyping but with a normal result by CMA. Eight pregnant women had chosen to terminate the pregnancy (5 with sex chromosome mosaicisms and 3 with autosomal mosaicisms). CONCLUSION For fetuses suspected for chromosomal mosaicisms, CMA, FISH and G-banding karyotyping should be combined to determine the type and proportion of mosaicisms more precisely in order to provide more information for genetic counseling.
Female ; Pregnancy ; Humans ; Mosaicism ; In Situ Hybridization, Fluorescence ; Chromosome Disorders/genetics* ; Prenatal Diagnosis/methods* ; Chromosome Aberrations ; Sex Chromosome Aberrations ; Microarray Analysis/methods* ; Chromosomes

OBJECTIVE: To explore the clinical and genetic characteristics of four patients with medium-chain acyl-CoA dehydrogenase deficiency (MCADD). METHODS: Four children who had presented at the Children's Hospital Affiliated to Zhengzhou University between August 2019 and August 2021 were selected as the study subjects. Clinical data of the children were collected. The children were subjected to whole exome sequencing (WES). RESULTS: All of the four children were diagnosed with MCADD. Blood amino acid and ester acyl carnitine spectrum test showed that the concentration of octanoyl carnitine (C8) was significantly increased. The main clinical manifestations included poor mental response (3 cases), intermittent diarrhea with abdominal pain (1 case), vomiting (1 case), increased transaminase (3 cases), and metabolic acidosis (2 cases). Five variants were identified by genetic testing, among which c.341A>G (p.Y114C) was unreported previously. Three were missense variants, one was frameshift variant and one was splicing variant. CONCLUSION The clinical heterogeneity of MCADD is obvious, and the severity of the disease may vary. WES can assist with the diagnosis. Delineation of the clinical symptoms and genetic characteristics of the disease can facilitate early diagnosis and treatment of the disease.
Child ; Humans ; Acyl-CoA Dehydrogenase/genetics* ; Carnitine ; Genetic Testing ; Lipid Metabolism, Inborn Errors/genetics* ; Neonatal Screening