The aim of this investigation was to determine the optimal storage medium for testicular hypothermic transportation and identify the ideal concentration for the application of the protective agent 5-aminolevulinic acid (5-ALA). Furthermore, this study aimed to explore the underlying mechanism of the protective effects of 5-ALA. First, we collected and stored mouse testicular fragments in different media, including Hank's balanced salt solution (HBSS; n = 5), Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12 (DMEM/F12; n = 5), and alpha-minimum essential medium (αMEM; n = 5). Storage of testicular tissue in HBSS preserved the integrity of testicular morphology better than that in the DMEM/F12 group ( P < 0.05) and the αMEM group ( P < 0.01). Testicular fragments were subsequently placed in HBSS with various concentrations of 5-ALA (0 [control], 1 mmol l -1 , 2 mmol l -1 , and 5 mmol l -1 ) to determine the most effective concentration of 5-ALA. The 2 mmol l -1 5-ALA group ( n = 3) presented the highest positive rate of spermatogonial stem cells compared with those in the control, 1 mmol l -1 , and 5 mmol l -1 5-ALA groups. Finally, the tissue fragments were preserved in HBSS with control ( n = 3) and 2 mmol l -1 5-ALA ( n = 3) under low-temperature conditions. A comparative analysis was performed against fresh testes ( n = 3) to elucidate the underlying mechanism of 5-ALA. Gene set enrichment analysis (GSEA) for WikiPathways revealed that the p38 mitogen-activated protein kinase (MAPK) signaling pathway was downregulated in the 2 mmol l -1 5-ALA group compared with that in the control group (normalized enrichment score [NES] = -1.57, false discovery rate [FDR] = 0.229, and P = 0.019). In conclusion, these data suggest that using 2 mmol l -1 5-ALA in HBSS effectively protected the viability of spermatogonial stem cells upon hypothermic transportation.
Male ; Animals ; Testis/cytology* ; Aminolevulinic Acid/pharmacology* ; Mice ; Organ Preservation/methods* ; Organ Preservation Solutions/pharmacology* ; Cryopreservation/methods*

Direct electrical stimulation of the human cortex can produce subjective visual sensations, yet these sensations are unstable. The underlying mechanisms may stem from differences in electrophysiological activity within the distributed network outside the stimulated site. To address this problem, we recruited 69 patients who experienced visual sensations during invasive electrical stimulation while intracranial electroencephalography (iEEG) data were recorded. We found significantly flattened power spectral slopes in distributed regions involving different brain networks and decreased integrated information during elicited visual sensations compared with the non-sensation condition. Further analysis based on minimum information partitions revealed that the reconfigured network interactions primarily involved the inferior frontal cortex, posterior superior temporal sulcus, and temporoparietal junction. The flattened power spectral slope in the inferior frontal gyrus was also correlated with integrated information. Taken together, this study indicates that the altered electrophysiological signatures provide insights into the neural mechanisms underlying subjective visual sensations.
Humans ; Male ; Female ; Adult ; Visual Perception/physiology* ; Electric Stimulation ; Middle Aged ; Young Adult ; Electrocorticography ; Electroencephalography ; Brain Mapping

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Objective To investigate the role of member septin family(SEPT12)in human spermatogenesis and its influence on sperm motility and sperm ultrastructure.Methods Whole exome sequencing(WES)was performed on peripheral blood DNA extracted from 375 patients with asthenoteratozoospermia,and a patient with idiopathic in-fertility carrying compound heterozygous mutation of SEPT12 was screened out.Sanger sequencing was performed to verify the mutation,and co-segregation analysis was performed in the family.The morphological abnormalities of sperm were analyzed by hematoxylin-eosin(HE)staining and scanning electron microscopy(SEM),and the ultra-structural defects of sperm were analyzed by transmission electron microscopy(TEM).Then the effects of the muta-tion on the level and position of the protein and the changes of the location and level of the defect structure markers were analyzed by Western blot and immune-fluorescence(IF).Results The compound heterozygous mutations c.C332A(p.Ti111K)and c.406_416 del TGCTCGTATTG(p.q136 VFS*39)in the SEPT12 gene were screened and identified in a patient with asthenoteratozoospermia.The mutations were verified by Sanger sequencing,which was consistent with the co-segregation genetic pattern of the family.The mutations resulted in loss of protein expres-sion,decreased sperm motility and sperm morphological deformities,mainly including short tail,curly tail and ir-regular sperm head.The ultrastructure of sperm showed that the annulus between the mid-piece and the principle-piece was missing,the acrosome membrane of sperm head fell off and the nucleus contained vacuoles.In the mid-piece of sperm flagella,the arrangement of mitochondrial sheath was disordered,most of flagella axoneme central pair was absent,microtubules doublet was missing or disordered,and some radical spoke was absent.By Western blot and IF,the marker proteins of related structural components were detected,and the results showed that the level of SEPT4 protein decreased,SEPT6 protein unchanged,acrosomal related proteins ACTL7A and ACROSIN protein missing,and the expression levels of mitochondrial and axoneme related proteins TOMM20,SPAG6 and RSPH3 protein significantly decreased.Conclusion The deletion of SEPT12 protein caused by SEPT12 gene mu-tation leads to the deletion of the annulus between the mid-piece and the principle-piece,and the abnormal assem-bly of sperm acrosome,mitochondrial sheath and flagella.

Objective To analyze the competition status and spatial autocorrelation of Beijing medical market from 2015 to 2019.Methods The Herfindahl-Hirschman Index(HHI)was used to calculate the degree of market competi-tion in 16 districts of Beijing,and the Moran index was used to calculate the spatial autocorrelation of market compe-tition.Results Except for the number of discharged patients,the average HHI of the number of health technicians,the number of beds and the total number of medical visits in 16 medical markets in Beijing from 2015 to 2019 showed a downward trend between 0.2 and 0.4,and the spatial global Moran index of the HHI index was all less than 0,showing a spatial negative correlation with the degree of competition in the medical market.Conclusion The medical market competition in Beijing is strengthened,the competition gap between urban and rural areas is large,and the competition in adjacent markets is mutually exclusive.It is suggested to strengthen the differentiated develop-ment of hospitals,strengthen the balanced layout between regions,and promote the low-competitive market with cross-regional medical association,forming a positive spillover effect.

Objective To establish a HS-GC test method for the determination of enflurane,isoflurane,diflurane,sevoflurane and its metabolite hexafluoroisopropanol(HFIP)in blood,and to establish a LC-MS/MS method for the determination of trifluoroacetic acid(TFA),the co-metabolite of enflurane,isoflurane,and deflurane in blood.Methods Place 0.5 mL blood sample in a 10 mL headspace bottle,add 1.0 mL ultrapure water to mix,then add 0.5 mL n-butanol internal standard solution,sealed and heated at 70℃for 20 min,take the upper layer of gas for HS-GC analysis,qualitatived by dual-column retention time and quantified by the internal standard curve;Blood sample was acetonitrile precipitated protein,separated by liquid chromatography,scanned with electrospray ionization(ESI),negative ion mode,and examined in multiple reaction monitoring mode(MRM),qualitatived by retention time and characteristic ions,quantified by standard curve.Results The detection limits(LOD)of enflurane,isoflurane,desflurane,heptaflurane,HFIP and TFA are 0.05,0.2,0.5,0.05,0.5 μg/mL and 0.5 ng/mL,and linear range as 1～100 μg/mL(TFA:1～100 ng/mL),with correlation coefficients greater than 0.999.The extraction recovery rate is between 30%and 80%,and the intra-day and inter-day precision are less than 5%.The accuracy is between 85%and 115%.Conclusion This method is quick and simple,and can be used for qualitative and quantitative analysis of enflurane,isoflurane,desflurane,sevoflurane and their metabolites in blood.

Objective To establish an analytical method combining gas chromatography-tandem mass spectrometry(GC-MS)and liquid chromatography-tandem mass spectrometry(LC-MS)to detect diazepam residue in bait nest materials and fish samples,and improve the pretreatment steps of samples to make the experimental results accurate and the sample processing convenient and fast.Methods Taking diazepam as the research object,samples were extracted with methanol and dichloromethane/n-hexane as solvents according to the type,and the supernatant was taken for detection after centrifugation.Results The diazepam standard sample showed a good linear relationship in the range of 10～10 000 ng/mL.The retention times in methanol and mixed solvent were 13.54 min and 13.83 min,respectively,and the correlation coefficients were 0.998 and 0.999,respectively;The limit of detection(LOD)of using methanol as extraction solvent was 2 ppb,and limit of quantification(LOQ)was 6 ppb.The LOD of using mixed solvents was 5 ppb,and the LOQ was 15 ppb.When the sample is a bait nest material,the GC-MS spectrum was clear and standard,and the peak shape was sharp and prominent;When the sample is biological specimen,the GC-MS spectra are disturbed by matrix,while the LC-MS data is more accurate and faster.Conclusion It is more appropriate to use GC-MS to determine the content of bait nest materialsamples,and it is more accurate to LC-MS to determine the content of fish samples due to the complexity of the organism.

The biological clock(also known as the circadian rhythm)is the fundamental reliance for all organisms on Earth to adapt and survive in the Earth's rotation environment.Circadian rhythm is the most basic regulatory mechanism of life activities,and plays a key role in maintaining normal physiological and biochemical homeostasis,disease occurrence and treatment.Recent studies have shown that the biologi-cal clock plays an important role in the development of oral tissues and in the occurrence and treatment of oral diseases.Since there is cur-rently no guiding literature on the research methods of biological clock in stomatology,researchers mainly conduct research based on pub-lished references,which has led to controversy about the research methods of biological clock in stomatology,and there are many confusions about how to rationally apply the research methods of circadia rhythms.In view of this,this expert consensus summarizes the characteristics of the biological clock and analyzes the shortcomings of the current biological clock research in stomatology,and organizes relevant experts to summarize and recommend 10 principles as a reference for the rational implementation of the biological clock in stomatology research.