In order to provide a thorough summary and analysis over sperm toxicity evaluation of medical devices for human
Humans ; Male ; Reproductive Techniques, Assisted ; Spermatozoa ; Toxicity Tests

BACKGROUNDExtensive research toward creating a biological pacemaker by enhancement of inward depolarizing current has been performed. However, studies have mainly focused on inducing spontaneous activity and have not adequately addressed ways to improve pacemaker function. In this study we attempted to improve pacemaker function by altering connexin expression in rat mesenchymal stem cells (MSCs) to a phenotype similar to native sinus node pacemaker cells.

METHODSTo generate a biological pacemaker, MSCs were transduced with a cardiac pacemaker gene-hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4), via transfection with a lentiviral vector. Funny current (I(f)) in HCN4(+) MSCs was recorded by voltage-clamp. Overexpression of connexin 45 (gene Gja7) in MSCs was achieved by transfection with the plasmid pDsRED2-N1-Gja7-RFP. Double-immunolabelling with anti-connexin 43 and anti-connexin 45 antibodies were used to identify the gap junction channels. The effects of the genetically modified MSCs on cardiomyocyte excitability were determined in MSCs cocultured with neonatal rat ventricular myocytes. Spontaneous action potentials of neonatal rat ventricular myocytes were recorded by current-clamp.

RESULTSHigh level time- and voltage-dependent inward hyperpolarization current that was sensitive to 4 mmol/L Cs(+) was detected in HCN4(+) MSCs, confirming that HCN4 acted as I(f) channels in MSCs. Connexin 43 and connexin 45 were simultaneously detected in CX45(+) MSCs. Beating frequency was (82 +/- 8) beats per minute (n = 5) in myocytes cocultured with non-transfected control MSCs, versus (129 +/- 11) beats per minute (n = 5) in myocytes cocultured with HCN4(+) MSCs. Myocytes cocultured with MSCs cotransfected with HCN4 and connexin 45 had the highest beating frequency at (147 +/- 9) beats per minute (n = 5).

CONCLUSIONThese findings demonstrate that overexpression of connexin 45 and subsequent formation of heteromeric connexin 45/connexin 43 gap junction channels in HCN4 expressing MSCs can improve their function as cardiac biological pacemakers in vitro.

Animals ; Animals, Newborn ; Biological Clocks ; physiology ; Cells, Cultured ; Connexins ; genetics ; metabolism ; Electrophysiology ; Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels ; Mesenchymal Stromal Cells ; cytology ; metabolism ; physiology ; Myocytes, Cardiac ; cytology ; metabolism ; physiology ; Potassium Channels ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction

This study was aimed at understanding the genome-wide characterization and variations for three imported novel coronavirus(SARS-CoV-2)strains from different sources in the same period in Jinan at the viral genome level,to provide a sci-entific basis for further improving the prevention and control of COVID-19 outbreaks at Jinan port.We selected nasal and pha-ryngeal swab samples from three cases of imported asymptomatic COVID-19infectionat Jinan port;performed second-genera-tion whole-genome sequencing;and analyzed the variant loci and homology withvarious bioinformatics software.The whole ge-nome sequence of SARS-CoV-2 was successfully obtained from three samples of asymptomatic infected cases,and had full lengths ranging from 29 835 bp to 29 844 bp.Pangolin typing results indicated that the genotypes of the three samples were O-micron BQ.1,BQ.1.1,and BQ.1.12.Compared with the original Wuhan strain,the three samples produced mutations at 77,80,and 78 base sites,respectively,involving 60-63 non-synonymous mutations,mainly in the S and ORF1ab genes.Omicron BQ.1 is an imported variant of the SARS-CoV-2 virus and was detected for the first time at Jinan port.From a molecular biolo-gy perspective,this study provides a theoretical basis for the source tracing and prevention and control of COVID-19 at theport.

er to detect the beam quality of the SC200 superconducting cyclotron,measure the beam at the extraction reference and the acceptance of the accelerator is realized.This article mainly introduces the design that use the scintillation screen at the extraction reference to measure the beam profile,position and use the Faraday cup to measure the current intensity with 2.5 level accuracy.The remoted controlling of probes and the acquisition and processing of signal based on LabVIEW and PLC.
Proton Therapy ; instrumentation

Objective:To investigate the expression and significance of the angiotensin Ⅱ and its receptors in lipopolysaccharide (LPS)-induced acute lung injury and acute kidney injury in rats.Methods:Forty eight Wistar rats were randomly divided into two groups: control group and endotoxin group (LPS group). LPS was injected through tail vein in LPS group, and the same amount of saline was injected through tail vein in control group.Samples were collected at 2 h, 6 h, 12 h and 24 h, respectively.The histopathology of lung and kidney was observed by HE staining.We detected lung wet/dry weight ratio, serum creatinine, urea nitrogen and Ang Ⅱ concentration in plasma, lung and kidney tissues by radioimmunoassay.Western blot and immunohistochemistry were used to detect the expression changes of AT1R and AT2R in lung and kidney tissue.Results:Compared with the control group, the pathology of lung and kidney tissue in LPS group showed different degrees of damage.The lung wet/dry weight ratio, serum creatinine and urea level in LPS group were significantly increased than that in control group( P<0.05). The Ang Ⅱ content in plasma increased significantly at 2 h and 6 h ( P<0.05), and the expression level of Ang Ⅱ in lung and kidney increased significantly at all time points ( P<0.05). The expression of AT1R in lung and kidney decreased significantly ( P<0.05), while the AT2R protein expression increased significantly ( P<0.05). Additionally the correlation analysis showed that the expression level of Ang Ⅱ and AT2R were positively correlated with lung and renal function, while the expression of AT1R was negatively correlated with lung and renal function. Conclusion:LPS results in the damage of lung and kidney function and the change of renin-angiotensin system.The changes of Ang Ⅱ and angiotension receptors were correlated with lung and kidney injury.Ang Ⅱ and angiotension receptors may be involved in LPS induced lung and kidney injury.

Objective We aimed to compare the efficacy and prognosis of percutaneous coronary intervention(PCI)in complex and high-risk patients with coronary heart disease(CHD)treated with extracorporeal membrane oxygenation(ECMO)combined with intra-aortic balloon pump(IABP)assistance,and explore the application value of combined use of mechanical circulatory support(MCS)devices in complex PCI.Methods A total of patients who met the inclusion criteria and underwent selective PCI supported by MCS at the Department of Cardiology,the First Affiliated Hospital of the Air Force Medical University from January 2018 to December 2022 were continuously enrolled.According to the mechanical circulatory support method,the patients were divided into ECMO+IABP group and IABP group.Clinical characteristics,angiographic features,in-hospital outcomes,and complications were collected.The intra-hospital outcomes and major adverse cardiovascular events(MACE)at one month and one year after the procedure were observed.The differences and independent risk factors between the two groups in the above indicators were analyzed.Results A total of 218 patients undergoing elective PCI were included,of which 66 patients were in the ECMO+IABP group and 152 patients were in the IABP group.The baseline characteristics of the two groups of patients were generally comparable,but the ECMO+IABP group had more complex lesion characteristics.The proportion of patients with atrial fibrillation(6.1％vs.0.7％,P=0.030),left main disease(43.9％vs.27.0％,P=0.018),triple vessel disease(90.9％vs.75.5％,P=0.009),and RCA chronic total occlusion disease(60.6％vs.35.5％,P＜0.001)was higher in the ECMO+IABP group compared to the IABP group.The proportion of patients with previous PCI history was higher in the IABP group(32.9％vs.16.7％,P=0.014).There was no statistically significant difference in the incidence of in-hospital complications between the two groups(P=0.176),but the incidence of hypotension after PCI was higher in the ECMO+IABP group(19.7％vs.9.2％,P=0.031).The rates of 1-month MACE(4.5％vs.2.6％,P=0.435)and 1-year MACE(7.6％vs.7.9％,P=0.936)were comparable between the two groups.Multivariate analysis showed that in-hospital cardiac arrest(OR 7.17,95％CI 1.27-40.38,P=0.025)and after procedure hypotension(OR 3.60,95％CI 1.10-11.83,P=0.035)were independent risk factors for the occurrence of 1-year MACE.Conclusions Combination use of ECMO+IABP support can provide complex and high-risk coronary heart disease patients with an opportunity to achieve coronary artery revascularization through PCI,and achieve satisfactory long-term prognosis.

Various types of medical devices used in assisted reproductive technologies (ART) should be detected for their safety by strict biological assays. Mouse embryo assay(MEA)has been recognized as one of the most important and standardized methods with the threshold more than 80% of blastocyst formation rate (BR) after 96 h culture of fertilized eggs. The disadvantage using BR for embryonic quality control has been concerned as it is ubiquitously dependent of embryonic morphology and the detailed data including molecular and genetic information is obviously missing and incomplete. This leads to the urgent requirement for more sensitive and efficient assessments for the quality control of ART. This study evaluated the reliability of an immunofluorescent MEA by counting total cell and differential number of the cells in the inner cell mass (ICM) and trophectoderm (TE) in the blastocyst. This method improved the traditional MEA, provided a sensitive and powerful platform to assess embryonic developmental viability and should be suggested as a standard assay to be globally used for the quality control of medical devices and pre-clinical procedures in ART.
Animals ; Blastocyst ; Embryonic Development ; Equipment Safety ; Mice ; Reproducibility of Results ; Reproductive Techniques, Assisted ; instrumentation

italic>Platycodon grandiflorum (Jacq.) A. DC is one of the most commonly used bulk medicinal herbs. It has important value in the fields of medicine, food and cosmetics, and its market demand is increasing year by year, and it has a good development prospect. In this study, based on 403 distribution records and 8 environmental variables, we used Maxent model to predict the potential distribution of P. grandiflorum under climate change. The results showed that the model simulation effect was the best when the Maxent parameter was FC (feature combination) = LQPH (L: linear features; Q: quadratic features; P: product features; H: hinge features) and RM (regularization multiplier) = 2.1, AUC (area under curve) = 0.901, and the model prediction showed that P. grandiflorum was widely distributed in 28 provinces of China under the current climate conditions, with a suitable area of 2 337 419.98 km². Under the influence of climate change in the future, the area of suitable habitat of P. grandiflorum showed a decreasing trend, and the distribution center as a whole showed a trend of northward and eastward shift. The distribution area of P. grandiflorum in the three main producing areas is affected by climate change, and the overall trend is that the future suitable distribution area of Chifeng in Inner Mongolia increases, while the future suitable distribution area of Zibo in Shandong and Taihe, Bozhou in Anhui decreases or even disappears under the SSP5-8.5 scenario (shared socioeconomic pathways). It is suggested to maintain and protect the ecological environment and germplasm resources of the reserved area suitable for the growth of P. grandiflorum, and increase the cultivation research in the expansion area of P. grandiflorum, so as to lay a foundation for the subsequent expansion of P. grandiflorum planting and to promote the protection and sustainable development of P. grandiflorum resources.