Objective:To investigate the protective effect of folic acid on melanocytes under oxidative stress.Methods:The normal human melanocyte cell line (PIG1) was cultured in vitro and divided into 5 groups to receive corresponding treatments: control group (normal culture for 48 hours without other treatment), H 2O 2 treatment group (normal culture for 24 hours followed by the treatment with 1 mmol/L H 2O 2 for another 24 hours), and 3 folic acid pretreatment groups (pretreatment with folic acid at concentrations of 50, 125, and 250 μmol/L for 24 hours followed by the treatment with 1 mmol/L H 2O 2 for another 24 hours). The cell viability was assessed using the cell counting kit 8 (CCK8) assay, the intracellular melanin content was measured by the sodium hydroxide solubilization method, cell apoptosis rates were detected by annexin V-fluorescein isothiocyanate/propidium iodide double staining, levels of intracellular reactive oxygen species (ROS) were detected using the fluorescent probe CM-H2DCFDA, the mitochondrial membrane potential was determined using the fluorescent probe JC-1, and the mitochondrial ultrastructure was observed by transmission electron microscopy. Comparisons among multiple groups were performed using one-way analysis of variance, and multiple comparisons were performed using Tukey test. Results:Compared with the control group, the H 2O 2 treatment group showed decreased cell viability (83.62% ± 3.77% vs. 99.99% ± 5.06%, P = 0.031), intracellular melanin content (68.48% ± 4.17% vs. 100.11% ± 2.30%, P < 0.001) and mitochondrial membrane potential (2.96 ± 0.26 vs. 5.86 ± 0.56, P = 0.002), but increased cell apoptosis rate (16.35% ± 1.20% vs. 6.45% ± 1.34%, P = 0.001) and intracellular ROS level (138.98% ± 2.74% vs. 100.00% ± 0.64%, P = 0.004). Compared with the H 2O 2 treatment group, the 125-μmol/L and 250-μmol/L folic acid pretreatment groups showed increased cell viability (106.21% ± 6.34%, 101.64% ± 6.77%, respectively; both P < 0.05) and intracellular melanin content (77.24% ± 3.85%, 88.34% ± 2.65%, respectively; both P < 0.05) ; the 50-μmol/L, 125-μmol/L and 250-μmol/L folic acid pretreatment groups all showed decreased cell apoptosis rates (9.40% ± 0.99%, 9.00% ± 1.13%, 6.50% ± 0.28%, P = 0.007, 0.005, 0.001, respectively) ; the 125-μmol/L and 250-μmol/L folic acid pretreatment groups showed decreased intracellular ROS levels (112.99% ± 4.21%, 101.36% ± 10.60%, P = 0.023, 0.005, respectively), but increased mitochondrial membrane potential (4.93 ± 0.25, 5.67 ± 0.35, P = 0.012, 0.003, respectively). Transmission electron microscopy showed damaged mitochondrial ultrastructure in melanocytes in the H 2O 2 treatment group, characterized by a substantial number of vacuolated mitochondria, intimal swelling, and reduced ridges, compared with the control group; compared with the H 2O 2 treatment group, the 250-μmol/L folic acid pretreatment group exhibited decreased degree of mitochondrial damage, manifesting as reduced mitochondrial vacuolization, clearer mitochondrial ultrastructure, and slight swelling of mitochondrial ridges. Conclusion:Folic acid could reduce the oxidative stress level in melanocytes, thus protecting melanocytes from oxidative stress.

Objective:To investigate the correlation between serum proprotein convertase subtilisin/Kexin type 9 (PCSK9) level and white matter hyperintensities (WMHs) in healthy population.Methods:Consecutive healthy individuals underwent routine physical examinations at the Department of Neurology, Jinling Hospital Affiliated to Medical School of Nanjing University (April 2023 to December 2023) and Hexi Branch of Nanjing First Hospital (March 2024 to April 2024) were included prospectively. Enzyme-linked immunosorbent assay was used to detect serum PCSK9 level. The Fazekas scale was used to assess the severity of WMHs (total score 0-6) and they were divided into no or mild WMHs group (0-2) and moderate to severe WMHs group (3-6). Multivariate logistic regression analysis was used to determine the independent correlation between the serum PCSK9 level and the severity of WMHs. Results:A total of 177 subjects were enrolled, including 110 males (62.1%), aged 66.7±10.1 years. The median serum PCSK9 level was 203.9 ng/L. According to the Fazekas score, there were 102 patients (51.6%) in the no or mild WMHs group, and 75 (42.4%) in the moderate to severe WMHs group. One way analysis of variance showed that serum PCSK9 level significantly increased with the increase of WMHs total score ( P=0.001). The serum PCSK9 level in the moderate to severe WMHs group was significantly higher than that in the no or mild WMHs group (437.2±260.4 ng/L vs. 217.9±141.7 ng/L; P=0.001). Multivariate logistic regression analysis showed that after adjusting for age, gender, and other confounding factors, there was a significant independent correlation between higher serum PCSK9 level and moderate to severe WMHs (odds ratio 3.201, 95% confidence interval 2.107-5.082; P=0.001). Conclusion:Higher serum PCSK9 level is an independent risk factor for moderate to severe WMHs in healthy individuals.

Objective:To investigate the effect of Edaravone and dexborneol(Eda.B)on oxidative stress pathway in peripheral blood of elderly patients with acute ischemic stroke.Methods:A total of 87 elderly patients with acute ischemic stroke in the Department of Neurology, Qinghai University Affiliated Hospital from July 2021 to January 2022 were selected as the study subjects.According to the random number table, they were divided into control group(44 cases)and edaravone dexborneol group(43 cases). Each group was divided into <12 h group, 12-24 h group and 24-48 h group according to the time of onset.Peripheral blood was collected in each group at admission and discharge, respectively.The serum levels of reactive oxygen species(ROS), Kelch-like epichlorohydrin-associated protein 1(Keap1), nuclear factor-E2-associated factor 2(Nrf2), heme oxygenase-1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1), tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6), as well as superoxide dismutase(SOD)activity and malondialdehyde(MDA)content were detected.Results:Elderly patients with acute ischemic stroke receving Eda.B treatment after admission could reduce the serum concentration of ROS, TNF-α and IL-6, as well as MDA content, and increase the concentration of Keap1, Nrf2, HO-1 and NQO1 and SOD activity.Except for ROS concentration in <12 h group and SOD activity in <12 h and 12 h-24 h groups, the differences between the other groups were statistically significant( P<0.05 for all). Compared with the control group, the serum concentration of TNF-α and IL-6 of patients in the Eda.B group at discharge decreased, while the concentration of Nrf2(24-48 h group)and HO-1(24-48 h group), and SOD activity increased, the differences were statistically significant( P<0.05 for all). In the control group at discharge, the concentrations of ROS(24-48 h group), TNF-α(<12 h group, 24-48 h group)and IL-6, as well as MDA content decreased, while the concentrations of Keap1, Nrf2(<12 h group, 12-24 h group)and HO-1(<12 h group, 12-24 h group)increased, the differences were also statistically significant( P<0.05 for all). Compared with admission, the concentration of Keap1(24-48 h group)and HO-1(24-48 h group), the activity of SOD(<12 h group, 12-24 h group)increased and the content of MDA(12-24 h group)in the Eda.B group decreased at discharge( P<0.05 for all). Conclusions:Eda.B can reduce oxidative stress and inflammatory response in peripheral blood of elderly patients with acute ischemic stroke by acting on the Keap1/Nrf2 pathway.

Objective:To explore the current situation of nursing human caring in hospital wards and analyze its influencing factors, so as to facilitate the development of nursing human caring practice.Methods:From July to November 2022, a total of 107 hospitals were surveyed through stratified convenience sampling method, and 4 072 ward nursing managers were recruited to finish the general information questionnaire and the ward nursing human caring status questionnaire. The general information included the region, class and type of the hospital, etc. The ward nursing human caring status questionnaire included 38 items in 5 dimensions of nursing human caring system and process, humanistic quality and training of nursing staff, humanistic environment and facilities, human caring procedures and measures, and human caring quality evaluation and improvement, with a full score of 190 points. Descriptive statistics were used to analyze the general data, independent samples t-test, ANOVA and correlation analysis were used to analyze the factors influencing the current status of nursing human caring in the ward, while multiple linear regression analysis was used to conduct a multivariate analysis. Results:The score of nursing human caring in hospital wards was 156.91±27.78. Whether the hospital had carried out nursing human caring pilot(demonstration) wards, whether the ward had previously been a hospital nursing human caring pilot(demonstration) nursing unit, the type of ward, and whether nursing managers had participated in human caring training were the influencing factors of the implication of nursing humanistic caring in wards( P<0.05). Conclusions:The practice of nursing human caring in hospital wards is at a good level, but needs to be further strengthened. Nursing managers should take systematically strategies to promote the development of nursing human caring practice.

Objective:To establish a melanoma cell line derived from a Chinese female patient of Han nationality with metastatic melanoma, and to study its basic biological characteristics.Methods:Metastatic melanoma cells were isolated from axillary lymph nodes of a 17-year-old female patient with malignant melanoma, and subjected to culture in vitro to establish a cell line. Short tandem repeat (STR) genotyping was performed to compare the information about the cell line and its derived tissue, and to detect gene mutations; cell counting kit-8 (CCK8) assay was conducted to assess the cellular proliferative activity, and soft agar cloning assay to assess the anchorage-independent proliferation; karyotype analysis was performed to determine the number and structure of chromosomes; with the highly aggressive melanoma cell line A2058 and keratinocyte line HaCaT serving as controls, Transwell assay was conducted to detect differences in cell migratory and invasive abilities, cell immunofluorescence assay and Western blot analysis were performed to determine the protein expression of melanoma-specific markers HMB45, S100 and Melan-A; the tumorigenicity was evaluated in vivo in a tumor-bearing mouse model. Results:A melanoma cell line was successfully established and named ZJMM-45, which was cultured for more than 70 passages over a 1-year period, and showed a stable shape and proliferative activity. The cells were spindle-shaped or polygonal, and could produce melanin. STR matching analysis showed that the ZJMM-45 sample was 96% matched with the cryopreserved lymph node tissue of the patient, suggesting that they were from the same source. A tumor-related gene BRAF V600E mutation (c.1799T>A) was identified in the ZJMM-45 cell line; karyotype analysis revealed that ZJMM-45 cells had triploid chromosomes and abnormal structures. ZJMM-45 cells grew exponentially in vitro and reached a plateau-phase in growth on day 5; the cells grew clonally and formed colonies in agar, showing anchorage-independent and malignant proliferative activity. Cell immunofluorescence assay and Western blot analysis showed that both ZJMM-45 and A2058 cells expressed HMB45, S100 and Melan-A; Transwell assay revealed that the numbers of invasive and migratory ZJMM-45 cells (300 ± 14, 260 ± 14, respectively) were significantly higher than those of invasive and migratory A2058 cells (150 ± 6, 160 ± 19, t = 13.25, 11.76, respectively, both P < 0.001) . The tumor-bearing mouse experiment showed that all 5 nude mice developed tumors with an inner diameter of 1.0 cm after 4 weeks, and the tumors were histopathologically characterized by proliferating hyperchromatic melanoma cell nuclei and formation of small nests, which were similar to primary solid tumors. Conclusion:The metastatic melanoma cell line ZJMM-45 derived from a Chinese patient with melanoma was successfully constructed, which carried the BRAF V600E mutation and expressed melanoma-specific markers, and was characterized by rapid proliferation, invasion and metastasis in both in vivo and in vitro culture, as well as obvious tumorigenicity in the in vivo experiment.

Objective:To explore effects of different loading modes of non-woven fabric and Tyvek packaging materials on degree of hydrogen peroxide adsorption and pressure during injection during low temperature plasma sterilization.Methods:From April to June 2019, 6 empty silicone resin instrument boxes were divided into two packaging methods in Disinfectant Supply Center of the First Affiliated Hospital of Zhengzhou University, 3 of which were double-packed with 100 cm 2 non-woven fabric and 3 of which were single-packed with 60 cm×20 cm Tvek paper-plastic bags. In the control group, the 3 non-woven packages to be sterilized were placed on the upper shelf of the sterilizer, and the 3 Tyvek packages to be sterilized were placed on the lower shelf. The loading order of the experimental group was reversed. The three packages of Tyvek packaging to be sterilized were placed on the upper shelf, and the three packages of non-woven packaging were placed on the lower shelf. The loading capacity of the two methods was 70%, and 20 times of sterilization were respectively carried out according to the normal process. The concentration of hydrogen peroxide adsorbed by the sterile bags was detected immediately after sterilization, and the pressure during each injection period was recorded. Results:The adsorption concentrations of hydrogen peroxide in sterile packages of non-woven fabric and Tevek in the experimental group were respectively (11.120±4.187) ppm and (8.205±4.181) ppm, and the difference was statistically significant ( t=2.203, P<0.05) . The adsorption concentrations of hydrogen peroxide of the two packaging materials in the control group were respectively (13.745±3.754) ppm and (8.065±4.599) ppm, and the difference was statistically significant ( t=4.279, P<0.01) . The difference in the adsorption concentration of non-woven fabrics between the two groups was statistically significant ( t=2.088, P<0.05) . There was no statistically significant difference in the adsorption of Tyvek between the two groups ( t=0.164, P>0.05) . The pressure during injection of the experimental group was (9.410±0.188) Torr, and that of the control group was (9.121±0.243) Torr, and the difference was statistically significant ( t=4.215, P<0.01) . Conclusions:When low temperature plasma sterilization of hydrogen peroxide is carried out, Tyvek packaging has adsorption of weak hydrogen peroxide, so it is more suitable for sterilization. In the mixed loading, the sterilization packages packed with Tyvek and non-woven fabric are respectively placed on the upper and lower layers, which can reduce the adsorption amount of hydrogen peroxide of packaging materials, improve the pressure during the injection period of sterilization and ensure the sterilization quality.

Objective: To analyze the epidemiological history, clinical manifestations, treatment and the short-term prognosis of 31 cases of 2019 novel coronavirus(2019-nCoV) infection in children from six provinces (autonomous region) in northern China. Methods: A retrospective analysis of the epidemiological history, clinical symptoms, signs, laboratory examinations, chest imaging, treatment and the short-term prognosis of 31 cases of 2019-nCoV was conducted. The patients were diagnosed between January 25th, 2020 and February 21st, 2020 in 21 hospitals in 17 cities of six provinces(autonomous region) of Shaanxi, Gansu, Ningxia, Hebei, Henan and Shandong. Results: The age of the 31 children with 2019-nCoV infection was 7 years and 1 month (6 months -17 years). Nine cases (29%) were imported cases. Other 21 cases (68%) had contact with confirmed infected adults. One case (3%) had contact with asymptomatic returnees from Wuhan. Among the 31 children, 28 patients (90%) were family cluster cases. The clinical types were asymptomatic type in 4 cases (13%), mild type in 13 cases (42%), and common type in 14 cases (45%). No severe or critical type existed. The most common symptom was fever (n=20, 65%), including 1 case of high fever, 9 cases of moderate fever, 10 cases of low fever. Fever lasted from 1 day to 9 days. The fever of fifteen cases lasted for ≤3 d, while in other 5 cases lasted > 3 d. Other symptoms included cough (n=14, 45%), fatigue (n=3, 10%) and diarrhea (n=3, 9%). Pharyngalgia, runny nose, dizziness, headache and vomiting were rare. In the early stage, the total leukocytes count in peripheral blood decreased in 2 cases (6%), the lymphocytes count decreased in 2 cases (6%), and the platelet count increased in 2 cases (6%).Elevation of C-reactive protein (10%, 3/30), erythrocyte sedimentation rate(19%,4/21), procalcitonin(4%,1/28), liver enzyme(22%, 6/27) and muscle enzyme (15%, 4/27) occurred in different proportions. Renal function and blood glucose were normal. There were abnormal chest CT changes in 14 cases, including 9 cases with patchy ground glass opacities and nodules, mostly located in the lower lobe of both lungs near the pleural area. After receiving supportive treatment, the viral nucleic acid turned negative in 25 cases within 7-23 days. Among them, 24 children (77%) recovered and were discharged from hospital. No death occurred. Conclusions In this case series, 2019-nCoV infections in children from six provinces (autonomous region) in northern China are mainly caused by close family contact. Clinical types are asymptomatic, mild and common types. Clinical manifestations and laboratory examination results are nonspecific. Close contact history of epidemiology, nucleic acid detection and chest imaging are important bases for diagnosis. After general treatment, the short-term prognosis is good.

Objective:To monitor the susceptibility of common used antimicrobial agents against nosocomial Gram-negative bacilli in 2018 across China.Methods:Prospective collection of Gram-negative bacilli from 13 teaching hospitals nationwide from January to December 2018. The minimal inhibitory concentration (MICs) of antibiotics such as meropenem was determined by agar dilution methods and broth microdilution methods. Interpretation of results using the Clinical and Laboratory Standards Institute(CLSI) 2019 M100S (29th Edition) standard. Data were analyzed by using WHONET-5.6 software.Results:A total of 1 214 non-repetitive Gram-negative bacilli were collected, accounting for 96.7% (1 174/1 214) of blood and sterile body fluid samples. The activity of antimicrobial agents against 871 strains of Enterobacteriaceae was as follows in descending order of susceptible rate: amikacin (93.2%, 812/871), meropenem (92.0%, 801/871), ertapenem (88.9%, 774/871), imipenem (88.4%, 770/871), piperacillin-tazobactam (84.0%, 732/871), cefoperazone-sulbactam (83.1%, 724/871), cefepime (71.4%, 622/871), minocyline (68.9%, 600/871), ceftazidime (66.9%, 583/871), levofloxacin (54.4%, 474/871).The resistance rates of Escherichia coli to the third generation cephalosporins were 61.5% (155/252) (ceftriaxone) and 60.7% (153/252) (cefotaxime), respectively. The resistance rates of Klebsiella pneumoniae to the third generation cephalosporins were 56.6% (126/222) (ceftriaxone) and 57.9% (129/222) (cefotaxime), respectively. The incidence of extended-spectrum β lactamase (ESBLs) positive E. coli and K. pneumoniae was 50.2% (127/252) and 18.2% (40/222), respectively. Over 95% of all the ESBLs positive strains were susceptible to imipenem and meropenem. The incidence of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae was 2.8% (7/252) and 20.4% (45/222), respectively. For Enterobacter cloacae, Klebsiella aerogenes, Citrobacter freundii, the most susceptible agent were tigecycline (96.3%-100%), followed by amikacin (94.9%-97.1%), meropenem (89.8%-96.6%)and imipenem (89.8%-94.9%).The susceptibility of Proteus mirabilis, Morganella morganii and Serratia marcescens to meropenem and amikacin was over 90%.A total of 67 strains of carbapenems resistant enterobacteriaceae(CRE) were detected. Modified carbapenem inactivation method showed, 45 strains were serine carbapenemase and 20 were metalloenzymes. The susceptibility of Pseudomonas aeruginosa to meropenem and imipenem were 73.2% (112/153) and 66.0% (101/153), respectively. Acinobacter baumannii has the highest sensitivity to colistin (100%, 163/163), followed by tigecycline (87.1%, 142/163).Compared with other sources of infection, specimens of bloodstream infections were less resistant to Klebsiella pneumoniae (17.6%, 27/153 vs 21.7%, 15/69) and Acinetobacter baumannii (68.3%, 71/104 vs 71.2%, 42/59). Escherichia coli (2.5%,4/198 vs 0%,0/54) and Pseudomonas aeruginosa (37%, 33/89 vs 18.8%, 12/64) have a high proportion of carbapenem resistance. Conclusions:Carbapenems still maintain high antibacterial activity against Enterobacteriaceae bacteria, especially strains producing only ESBLs. Carbapenem-resistant Klebsiella pneumoniae should be given sufficient attention. Carbapenemase is the most important drug resistance mechanism of carbapenem-resistant Enterobacteriaceae in China.

We examined the neural correlates of the statistical learning of orthographic-semantic connections in Chinese adult learners. Visual event-related potentials (ERPs) were recorded while participants were exposed to a sequence of artificial logographic characters containing semantic radicals carrying low, moderate, or high levels of semantic consistency. The behavioral results showed that the mean accuracy of participants' recognition of previously exposed characters was 63.1% that was significantly above chance level (50%), indicating the statistical learning of the regularities of semantic radicals. The ERP data revealed a temporal sequence of the neural process of statistical learning of orthographic-semantic connections, and different brain indexes were found to be associated with this processing, i.e., a clear N170-P200-N400 pattern. For N170, the larger negative amplitudes were evoked by the high and moderate consistency than the low consistency. For P200, the mean amplitudes elicited by the moderate and low consistency were larger than the high consistency. In contrast, a larger N400 amplitude was observed in the low than moderate and high consistency; and more negative amplitude was elicited by the moderate than high consistency. We propose that the initial potential shifts (N170 and P200) may reflect orthographic or graphic form identification, while the later component (N400) may be associated with semantic information analysis.

OBJECTIVE: To identify pathogenic variations of EXT1 and EXT2 genes in two Chinese pedigrees affected with hereditary multiple exostosis (HME). METHODS: Genomic DNA was extracted from peripheral blood samples using a phenol-chloroform method. PCR and Sanger sequencing was conducted to amplify the exons and the flanking intronic regions of the EXT1 and EXT2 genes. RESULTS: DNA sequencing has revealed a heterozygous missense variation c.812A>G (p.Tyr271Cys) in the exon 1 of EXT1 in pedigree 1, and a heterozygous frameshift variation c.1431dup (p.Ser478Leufs*43) in the exon 6 of EXT1 in the proband from pedigree 2. Both variations have co-segregated with the disease phenotype, which was also consistent with previous report. CONCLUSION Two heterozygous pathogenic variations underlying HME have been identified. The result has facilitated genetic counseling and prenatal diagnosis for the affected pedigrees.
Asian Continental Ancestry Group ; Base Sequence ; DNA Mutational Analysis ; Exostoses, Multiple Hereditary ; genetics ; pathology ; Frameshift Mutation ; Humans ; Mutation, Missense ; N-Acetylglucosaminyltransferases ; genetics ; Pedigree