BACKGROUND:The research of dental stem cells in the fields of regenerative medicine and tissue engineering has been deepening,bringing hope for the repair of tooth-related tissues and the treatment of systemic diseases.However,there is a lack of systematic research and analysis on the biological characteristics of dental stem cells in different age groups. OBJECTIVE:To explore the biological characteristics of the human deciduous tooth and permanent tooth pulp stem cells cultured in umbilical cord blood platelet lysate to provide a reliable basis for human platelet lysates to replace fetal bovine serum. METHODS:The pulp tissues of deciduous teeth,juvenile permanent teeth and adult permanent teeth were taken out and cultured in DMEM/F-12 medium supplemented with 10%fetal bovine serum or different concentrations(5%,10%and 15%)of human platelet lysates.Cell proliferation in the four groups was detected by cytometry.The optimal concentration of human platelet lysates was selected for subsequent experiments.Under the optimal concentration of human platelet lysates,human deciduous tooth and juvenile and adult permanent tooth pulp stem cells were cultured in vitro.The cell growth status was observed under the microscope.The specific antigen on the cell surface was detected by flow cytometry.The cell proliferation ability was tested by the cell counting method and CCK-8 assay.The cell differentiation ability in vitro was observed by a three-line differentiation assay. RESULTS AND CONCLUSION:(1)The cell proliferation rate of the 10%human platelet lysate group was the highest.(2)In all three groups,fusiform fibrous cells grew and expanded from around the tissue block.There was no significant difference between deciduous teeth and juvenile permanent tooth cells,but the adult permanent tooth cells were larger than the deciduous and juvenile permanent tooth cells of the same generation.(3)The results of flow cytometry showed that deciduous teeth,juvenile permanent teeth and adult permanent teeth conformed to the phenotypic characteristics of mesenchymal stem cells.(4)The proliferative capacity of adult permanent dental pulp stem cells was significantly lower than those of deciduous teeth and juvenile permanent dental pulp stem cells(P<0.01).(5)mRNA expressions of osteoblast-related genes alkaline phosphatase and bone morphogenetic protein 2,lipoprotein lipase and peroxisome proliferator-activated receptor γ2,mRNA expressions of chondroblast related gene type II collagen α1 and cartilage oligomeric matrix protein in adult pulp stem cells of permanent teeth were significantly lower than those of deciduous teeth and juvenile permanent teeth pulp stem cells(P<0.01).(6)Compared with adult dental pulp stem cells,human deciduous teeth and juvenile permanent teeth dental pulp stem cells have the stronger proliferative capacity and multidirectional differentiation potential,and are more suitable for clinical research and disease treatment.

Objective:To investigate the current status on fundamental construction of clinical laboratories in China.Methods:A web-based external quality assessment (EQA) system was used to collect basic information from the clinical laboratories that participated in EQA program of National Center for Clinical Laboratory in 2023. The indicators include the construction of laboratory information systems (LIS), laboratory building area, human resource, and the number of clinical testing item. The comparisons of the indicators between different types of laboratories were tested.Results:A total of 14 405 clinical laboratories submitted the required information in 2023. Guangdong province accounted for the highest proportion of the numver of laboratories, which is 10.6% (1 533/14 405). The building area and staff numbers in the independent clinical laboratory were higher than other institutions, which were 1 400 (850, 2 196) m 2 and 20 (12, 35), respectively. The building areas, the staff numbers and the number of clinical testing item of tertiary hospitals and general hospitals were significantly higher than other hospitals. The building areas of the tertiary hospitals and the general hospitals were respectively 1 050 (600, 1 800) m 2 and 1 000 (500, 1 600) m 2, and the staff numbers were respectively 30 (19, 45) and 26 (17, 39). Besides, the number of clinical testing item were 287 (189, 388) and 285 (198, 378), respectively. The proportion of staff in hospitals with master′s degrees or higher titles was 18.2% (52 138/286 855). Meanwhile, 17.4% (49 280/282 528) of the staff had higher academic title. It showed that 24.5% (3 528/14 405) of the clinical laboratories still have no LIS. Conclusion:The fundamental construction in different type of clinical laboratories varied significantly in China. The clinical laboratories should strengthen the construction of information systems and pay more attention to human resources.

Approximately 140 million people worldwide are homozygous carriers of APOE4 (ε4), a strong genetic risk factor for late onset familial and sporadic Alzheimer's disease (AD), 91% of whom will develop AD at earlier age than heterozygous carriers and noncarriers. Susceptibility to AD could be reduced by targeted editing of APOE4, but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies. Here, we first screened eight cytosine base editor variants at four injection stages (from 1- to 8-cell stage), and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate (up to 100%) with the lowest bystander effects. In particular, 80% of AD-susceptible ε4 allele copies were converted to the AD-neutral ε3 allele in human ε4-carrying embryos. Stringent control measures combined with targeted deep sequencing, whole genome sequencing, and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells. Furthermore, base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage. Finally, we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia. Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos, a potential approach for reducing human susceptibility to AD or other genetic diseases.
Humans ; Apolipoprotein E4/genetics* ; Cytosine ; Mutation ; Blastocyst ; Heterozygote ; Gene Editing ; CRISPR-Cas Systems

Objective:To establish preliminary quality specifications for emergency examination turnaround time (TAT).Methods:The National Center for Clinical Laboratories organized 31 provinces (autonomous regions and municipalities directly) and Xinjiang production and Construction Corps centers to launch a synchronous Quality Indicators (QIs)-External Quality Assessment (EQA) program and the collected data were reported via developed online EQA system. The essential information of the clinical laboratories, the data of pre-examination and intra-laboratory TAT quality indicators of emergency departments at each specialty (biochemistry, automatic immunity, three routines tests and coagulation) and four specific tests (blood potassium, troponin I/T, white blood cell count and international normalized ratio (INR)) were collected from 2019 to 2021. TAT returned the median and 90th percentile ( P90) of the specified month were calculated. The median (lower quartile, upper quartile) of the TAT returned laboratories were calculated and second result grading statistics for 2021 (2 422 tertiary hospital and 5 088 secondary hospital) were performed to understand the difference of pre-examination and the laboratory TAT between different tertiary hospitals. Results:From 2019 to 2021, there were 9 540 laboratories, 9 709 laboratories and 10 653 returned laboratories. The pre-examination TAT of each specialty was similar, and the results were relatively stable. The median distribution was about 15 (10, 30) min, and the monthly P90 distribution was about 20 (10, 30) min. The distribution results of the median intra-laboratory TAT in each specialty were as follows: automatic immunity≥biochemistry>coagulation>three routine tests. The distribution of the latest (second result in 2021) survey results of each specialty were as follows: automatic immunity 53 (30, 60) min, biochemistry 45 (30, 60) min, coagulation 30 (23, 40) min, and three routine tests 20 (11, 30) min. The median results of monthly P90 of intra-laboratory TAT were as follows: 60 min for automatic immunity and biochemistry specialty, about 38 min for coagulation specialty, and about 27 min for three routines tests. The hierarchical statistical results showed that the monthly P90 distribution of laboratory TAT of the pre-examination and intra-laboratory TAT from the tertiary hospital was higher than that of the secondary hospital. The pre-examination TAT of each specialty of the tertiary hospital/secondary hospital was as follows: biochemistry 35 (22, 60)/20 (11, 30) min, automatic immunity 33 (20, 60)/20 (10, 30) min, three routine tests 30 (20, 49)/20 (10, 30) min and coagulation 31 (20, 58)/20 (10, 30) min, the intra-laboratory TAT of each specialty of the tertiary hospital/secondary hospital was as follows: biochemistry 65 (50, 91)/60 (40, 70) min, automatic immunity 75 (55, 113)/60 (40, 90) min, three routine tests 30 (23, 38)/28 (19, 30) min and coagulation 53 (36, 72)/35 (30, 57) min. In terms of the distribution results of the median of intra-laboratory TAT of the four specific tests, 96.76% (9 484/9 801) of the blood potassium and 95.96% (8 733/9 101) of the troponin I/T medical institutions were TAT within 69 min in the laboratories, 95.34% (9 679/10 152) of the white blood cell count medical institutions were TAT within 31 min in the laboratories, and 98.85% (9 462/9 572) of the INR medical institutions were TAT within 66 min in the laboratories. Conclusions:This survey provides a preliminary quality specification for the emergency department turnaround time at each specialty. Lower quartile, median and upper quartile of the monthly P90 at the tertiary and secondary hospitals can be used to define the best, appropriate and minimum performance levels, respectively.

Objective:To analyze the implementation of the external quality assessment plan for quality indicators of clinical laboratories in China from 2016 to 2021, as well as that of the external quality assessment of 15 quality indicators in clinical laboratories, in order to provide reference for quality management of clinical laboratory specialties.Methods:The research data was collected from the external quality assessment plan for quality indicators, which was conducted by the National Center for Clinical Laboratories joining the clinical laboratory centers of 31 provinces (autonomous regions and municipalities directly). The essential information reported by each participating clinical laboratory from 2016 to 2021 and the external quality assessment data of 15 quality indicators in clinical laboratories were collected, followed by a descriptive analysis on the number of participating laboratories and the number of returns for each indicator. Median representation was used for the external quality assessment data of 15 quality indicators in clinical laboratories, and the TOPSIS method was applied to comprehensively evaluate the quality of the total testing process of participating clinical laboratories in each year.Results:From 2016 to 2021, the number of laboratories participating in the external quality assessment plan for quality indicators of clinical laboratory increased from 7 704 to 12 142. Quality indicators in pre-analytical phases: the incorrect sample type rate, incorrect sample container rater, and incorrect fill level rate had been decreasing year by year, reaching 0, 0, and 0.005 8% in 2021, respectively. The anticoagulant samples clotted rate had decreased from 0.068 6% in 2016 to 0.042 8% in 2021, and the blood culture contamination rate from 2017 to 2021 had been 0 without exception. The pre-examination turnaround time had been shortened from 28 minutes in 2016 to 2019 to 24 minutes in 2020 and 2021. Quality indicators in analytical phases: the intra-laboratory turnaround time had been extended from 45 minutes in 2016 to 2019 to 50 minutes in 2020 and 2021. Test covered by an IQC rate had been increasing year by year, reaching 60.61% in 2021. Test with inappropriate IQC performances rate was 0 in 2020 and 2021, the test covered by an EQA-PT control rate was 100%, and unacceptable performances in EQA-PT schemes rate from 2017 to 2021 was 0. The inter-laboratory comparison rate had increased from 1.56% in 2016 to 3.00% in 2021. Quality indicators in post-analytical phases: the incorrect laboratory reports rate, critical values notification rate and timely critical values notification rate had been 0, 100%, and 100%from 2016 to 2021 respectively. The comprehensive evaluation results of TOPSIS method showed that the overall quality level of clinical laboratory testing in 2020 was the highest, with Ci value of 0.850 5, while the lowest Ci value in 2016 was 0.143 6. Conclusions:The quality of clinical laboratory testing in China has been effectively improved. Clinical laboratories should continue to strengthen their monitoring of quality indicators, especially the intra-laboratory turnover time and the inter-laboratory comparison rate, for the purposes of identifying errors, analyzing causes and taking corrective measures to improve quality.

Objective:By reviewing and analyzing the results of external quality assessment of pre-test quality indicators related to the acceptability of microbiology laboratory sample from 2016-2021, we aimed to understand the acceptability of microbiology laboratory sample and therefore to provide a reference for establishing preliminary quality specifications.Methods:The National Center for Clinical Laboratories organized 31 provinces (including autonomous regions and municipalities directly under the Central Government) and the Xinjiang production and Construction Corps centers to launch a synchronous Quality Indicators (QIs)-External Quality Assessment (EQA) program and the collected data were reported via an online EQA system. The essential information of the clinical laboratories and the data of quality indicators from 2016 to 2021 were collected and the data from overall, continuous return laboratories were analyzed. Sigma values were calculated to assess the quality level of laboratory.Results:The median of the 13 quality indicators of national laboratories for all years was 0 (except for the first microbiological contaminated sample rate in 2018). Ten of the quality indicators (incorrect fill level rate, sample loss rate, misidentified sample rate, unsuitable sample for storage rate before analysis, sample damaged rate during transportation, sample transported at inappropriate temperature rate, sample with excessive transportation time rate, inappropriate time in sample collection rate, sample recollection rate for error due to laboratory staff, sample recollection rate for error not due to laboratory staff) had quartiles of 0 for all years, reaching six sigma level. The results of the median (upper quartile) of each year of the three quality indicators of continuous return laboratories for tertiary hospitals show that the incorrect sample container rate was the lowest, followed by the incorrect sample type rate, and the microbiological contaminated sample rate was the highest. The highest values of corresponding median (upper quartile) results were 0.047% (0.191%), 0.059% (0.252%), 0.251% (0.6%) respectively. The median incorrect sample type rate and median incorrect sample container rate in 2016/1 and 2021/1 tertiary hospitals were ranked by province respectively. The median for the incorrect sample type rate of Liaoning, Hebei, Jiangxi, Tianjin, Beijing, Guizhou, Gansu, Qinghai and Ningxia tertiary hospitals in 2021/1 was significantly lower than the respective values in 2016/1, and the median for incorrect sample container rate of Liaoning, Sichuan, Zhejiang, Hubei, Shanxi, Tianjin, Chongqing, Guizhou, Ningxia and Hunan tertiary hospitals in 2021/1 was significantly lower than those respective values in 2016/1.Conclusions:The results of the sample acceptability of microbial laboratory are generally acceptable. The laboratories should explore and establish their own quality indicators system, strengthen the long-term monitoring of key quality indicators and improve their service quality.

Objective:To investigate the use of the reference intervals for blood cell counting and the reference of industry standard in China.Methods:Information from all laboratories was collected using online questionnaire in 18 reference intervals survey in blood cell counting in 2019. The information includes the source of the reference intervals, the verification of the reference intervals, and the upper and lower limits of the reference intervals, the method used, the instrument, the reagent and the calibrator. Microsoft Excel 2007 software was used to analyze the results of all laboratories. The median and 95% confidence interval were calculated. The distribution of the reference intervals for blood cell counting and their conformance to industry standards were analyzed.Results:2, 869 labs reported the data. The main sources were industry standards and National Guide to Clinical Laboratory Procedures. The proportion was 33.30%-35.02% and 28.55%-30.90% respectively. 49.44%-55.13% of laboratories validated the reference interval when citing industry standards. The reference interval grouping of most laboratories (89.37%-91.69%) cited in RBC, Hgb and Hct were consistent with the industry standards. We compared the upper and lower limits of the reference intervals with that given by the industry standards, when the lower limit of the reference intervals of mean corpuscular hemoglobin concentration, absolute neutrophils count, absolute basophils count, absolute monocyte count, and lymphocyte percentage were compared. The upper limit of reference intervals of neutrophils percentage as well as upper and lower limits of reference intervals of mean corpuscular volume, mean corpuscular hemoglobin, absolute eosinophil count, basophils percentage, and monocyte percentage were also compared. The median and mode were equal and consistent with industry standards. For other labs, the upper and lower limits of the reference intervals were not consistent with the reference intervals given by the industry standards.Conclusion:The use of reference intervals for blood cell counting was not the same, and the implementation of industry standards was not optimistic. A considerable number of laboratories had not verified the reference intervals, so it was necessary to promote the industry standards for reference intervals.

Objective:To explore the effect of the interval of radical prostatectomy after prostate puncture on the perioperative period and prognosis of patients.Methods:Patient’s data from September 2016 to September 2018 whom performed laparoscopic radical prostatectomy at the Affiliated Hospital of Xuzhou Medical University were collected and retrospectively analyzed. All prostate biopsy confirmed prostate cancer and 66 patients underwent laparoscopic radical prostatectomy. The average age was (70.11 ± 5.01) years, ranged from 60 to 79 years. The patients were divided into two groups according to the interval time from prostate biopsy to laparoscopic radical prostatectomy: <7 d group ( n=32) and 6-8 weeks group ( n= 34). The operation time, intraoperative blood loss, postoperative hospital stays, positive rate of incisional margin, postoperative urinary incontinence rate and the rate of urinary incontinence 6 months after operation, rate of postoperative erectile dysfunction and bone metastasis were compared and analyzed between the two groups. When the data conformed to the normal distribution, the data were expressed in Mean±standard deviation ( Mean± SD), and the independent sample t-test was used to evaluate the statistical significance between groups. When the data did not conform to the normal distribution, the measurement data was expressed as Median (interquartile range) [ M( P25, P75)], and the Mann-Whitney U test was used for the comparison between groups. Count data comparison between groups using Chi-square test or Fisher exact probability method. Unconditional multivariate Logistic regression was used to analyze the relationship between outcome and exposure. Results:All the 66 patients successfully underwent surgery, the surgery success rate was 100%. The average operation time of <7 d group and group 6-8 weeks group was [185.00(174.50, 193.50)] min and [183.00(175.00, 187.50) min], respectively, the difference was not statistically significant ( P=0.685 8, U=512.0). The average intraoperative blood loss of group <7 d group and 6-8 weeks group was [185.50(177.75, 205.25)]ml, [189.00(180.75, 206.00)] ml, respectively, the difference was not statistically significant ( P=0.685 9, U=512.0). The average postoperative hospital stays of <7 d group and 6-8 weeks group was [14.00(11.75, 16.00)] d, [13.50(12.00, 15.00)] d, respectively, the difference was not statistically significant ( P=0.785 7, U=522.5). The positive rate of incisal margin of<7 d group and 6-8 weeks group was 18.75%, 14.71%, respectively, the difference was not statistically significant ( P=0.659 5, χ2=0.194). The postoperative urinary incontinence rate of <7 d group and 6-8 weeks group was 6.25% and 8.82%, respectively, the difference was not statistically significant ( P=1.000 0). The urinary control after follow-up for six months of <7 d group and 6-8 weeks group was 6.25% and 2.94%, respectively, the difference was not statistically significant ( P=0.607 7). The postoperative erectile dysfunction rate of<7 d group and group 6-8 weeks group was 9.38% and 8.82%, respectively, the difference was not statistically significant ( P=1.000 0). The postoperative bone metastasis rate of group<7 d and 6-8 weeks group was 6.25% and 5.88%, respectively, the difference was not statistically significant ( P=1.000 0). Conclusions:Performing laparoscopic radical prostatectomy within 7 days following prostate biopsy did not adversely affect the postoperative outcomes and prognosis, also not increased postoperative complications, can shorten the patient′s treatment cycle.

Objective:To analyze the epidemiological characteristics of human brucellosis (HB), evolution and origin feature of Brucella strains in Tongliao city, Inner Mongolia Autonomous Region during 2004-2018, and to provide evidence for strategy development against the disease. Methods:Data from the reports on HB in Tongliao during 2004-2018 were extracted from the China Information System for Disease Control and Prevention before being analyzed with software Excel 2016. Epidemiologic feature was described, using the number of cases, constituent ratio and related rates. Conventional biotypes methods were used for identification of species/biovars strains while species of six Brucella strains were further verified by AMOS-PCR. Cluster analyze on six Brucella strains were performed with Bio-Numerics 5.0 software and for examining and revealing the genetic characteristics of the related strains. Results:During 2004-2018, a total of 16 704 HB cases were reported, with the incidence rate as 35.41/100 000. The incidence rates appeared as 110.51/100 000 in Jarud Banner and 67.84/100 000 in Kulun flag, which were both higher than the other areas. Most of the cases were reported in the 40 -54 year olds, which accounted for 48.75% (8 143/16 704). The number of HB in farmers appeared as 14 873, which counted for 89.04% (14 873/16 704) of all the cases. Male to female ratio of incidence was 2.40∶1. Most of the reported cases appeared between March to May, which accounted for 56.30% (9 405/16 704). Peak of the disease was seen in April. Using the conventional identification method, results showed that the available six strains all belonged to B. melitensis, including three of them as B. melitensis bv.1 and others three strains as B. melitensis bv. 3. Results from the amplified AMOS-PCR showed that all the strains were B. melitensis. The six strains clustered in two MLVA-11 genotypes (111 and 116) and all belonged to the Eastern Mediterranean lineage. Based on the MLVA-16 cluster analysis, results suggested that strains from this study were having close genetic relationship with B. melitensis strains that were from Jilin and Heilongjiang provinces. Conclusions:Human brucellosis identified in Tongliao area was with greater risk in spreading the disease to the vicinity. Our findings indicated that the programs on detection and control of the disease should be strengthened.

Objective: To compare the lateralization accuracy and localization accuracy of MRI, interictal ¹⁸F-fluorodeoxyglucose(FDG) and ¹¹C-flumazenil(FMZ) PET/CT imaging for refractory epilepsy(REP) in patients with hippocampal sclerosis(HS). Methods: A total of 41 classical HS patients (25 males, 16 females; age: 15-61 years) with REP from General Hospital of Northern Theater Command of PLA between January 2017 and October 2018 were retrospectively analyzed. All patients underwent MRI, interictal ¹⁸F-FDG and ¹¹C-FMZ PET/CT imaging, followed by the resection of epileptogenic foci. The pathological diagnosis was taken as the gold standard. Visual and semi-quantitative analyses were used to analyze the images. The lateralization accuracy and localization accuracy of the three imaging methods for epileptogenic foci were calculated and compared(χ² test). Results: The lateral accuracy and localization accuracy of MRI were 70.73%(29/41) and 60.98%(25/41), those of interictal ¹⁸F-FDG PET/CT imaging were 78.05%(32/41) and 70.73%(29/41), and those of interictal ¹¹C-FMZ PET/CT imaging were 100%(41/41) and 100%(41/41), respectively. The interictal ¹¹C-FMZ PET/CT imaging was the best among 3 imaging methods(χ² values: 1.976-12.902, all P<0.01). Conclusions All 3 imaging methods have their advantages and limitations. The interictal ¹¹C-FMZ PET/CT imaging has a high value in the localization of classical HSREP, which can significantly improve the diagnostic accuracy of classical HSREP and guide clinical operation.