Objective·To observe the impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting(FVFG)for osteonecrosis of femoral head(ONFH).Methods·Between October 2001 and December 2013,370 patients diagnosed with ONFH(556 hips)underwent FVFG.Preoperative synovitis was assessed using magnetic resonance imaging(MRI)and quantified with the Hip Inflammation MRI Scoring System(HIMRISS).Patients were divided into no synovitis group,moderate synovitis group,and severe synovitis group.Harris hip scores and the incidence of total hip arthroplasty were collected with an average follow-up duration of 90.5 months(range:5-215 months).Hip survival failure(defined as a Harris hip score lower than 80 at the final follow-up or the occurrence of total hip arthroplasty)was calculated.Multivariable Cox regression analysis was adopted to compare the influence of different degrees of synovial inflammation on long-term prognosis.Results·The proportion of hip survival failure was 28.0％in patients without synovitis and 28.5％in those with moderate synovitis,whereas it was significantly higher(60.4％)in patients with severe synovitis.The results of multivariable Cox regression analysis showed that severe synovitis was an independent risk factor for poor prognosis(HR 2.06,95％CI 1.21-3.53)after adjusting for age,gender,education level,marital status,ONFH type,affected side of ONFH,smoking history,baseline Harris hip score and other hip MRI-based covariates(collapse,bone marrow edema,and degeneration).Conclusion·Severe synovitis in patients with ONFH significantly increases the failure rate of hip preservation after FVFG,and the severity of synovitis should be considered in surgical decision-making.

Objective·To observe the impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting(FVFG)for osteonecrosis of femoral head(ONFH).Methods·Between October 2001 and December 2013,370 patients diagnosed with ONFH(556 hips)underwent FVFG.Preoperative synovitis was assessed using magnetic resonance imaging(MRI)and quantified with the Hip Inflammation MRI Scoring System(HIMRISS).Patients were divided into no synovitis group,moderate synovitis group,and severe synovitis group.Harris hip scores and the incidence of total hip arthroplasty were collected with an average follow-up duration of 90.5 months(range:5-215 months).Hip survival failure(defined as a Harris hip score lower than 80 at the final follow-up or the occurrence of total hip arthroplasty)was calculated.Multivariable Cox regression analysis was adopted to compare the influence of different degrees of synovial inflammation on long-term prognosis.Results·The proportion of hip survival failure was 28.0％in patients without synovitis and 28.5％in those with moderate synovitis,whereas it was significantly higher(60.4％)in patients with severe synovitis.The results of multivariable Cox regression analysis showed that severe synovitis was an independent risk factor for poor prognosis(HR 2.06,95％CI 1.21-3.53)after adjusting for age,gender,education level,marital status,ONFH type,affected side of ONFH,smoking history,baseline Harris hip score and other hip MRI-based covariates(collapse,bone marrow edema,and degeneration).Conclusion·Severe synovitis in patients with ONFH significantly increases the failure rate of hip preservation after FVFG,and the severity of synovitis should be considered in surgical decision-making.

Objective: To monitor the prevelance of Neisseria meningitidis among healthy children and adolescents aged 3-18 in Anhui Province, so as to provide support for epidemic cerebrospinal meningitis prevention and control. Methods: From September to October in 2021 and 2022, 4 033 healthy children and adolescents aged 3-18 were selected by stratified random sampling from Anhui Province, including areas north of the Yangtze River (Bozhou, Fuyang, Bengbu, Huainan, Chuzhou, Hefei) and areas south of the Yangtze River (Wuhu, Maanshan, Tongling, Anqing, Chizhou, Xuancheng) and the secretions of children and adolescents were collected from the posterior pharyngeal wall above the uvula, and the strains were identified by bacterial culture and nucleic acid detection. McNemar test and Kappa consistency test were used for statistical analysis. Chisquare test and Chisquare trend test were used to compare the rates. Results: The carrier rates of Neisseria meningitidis were 0.47% and 1.07%, respectively. The sensitivity of nucleic acid detection was higher. Among the detected bacteria, group B accounted for the largest proportion of 76.74%. It was followed by group C (4.65%), group Y (4.65%), group W 135 (2.33%) and group X (2.33%). The bacteria bearing rate of male students was higher than that of female students (χ2=11.44); with the increase of age, the bacteria bearing rate of children and adolescents showed an increasing trend (χ2trend=42.69); the bacterial bearing rate of children and adolescents in the north of the Yangtze River was higher than that in the south of the Yangtze River (χ2=23.19); the bacteria bearing rate of children and adolescents without immune history was higher than that with immune history (χ2=11.02)(P<0.01). Conclusions Neisseria meningitidis group B has become an epidemic strain in Anhui Province, and senior children and adolescents have become the key population of epidemic prevention and control. It is necessary to continue to do a good job in the surveillance of epidemic cerebrospinal meningitis disease and focuse on group B disease cases, so as to prevent the occurrence of cluster outbreaks in schools.

Gene editing technology has been a hotspot in the field of biotechnology. CRISPR/Cas systems are efficient gene editing tools because of its specificity, simplicity and flexibility, these features enabled the rapid application of CRISPR/Cas systems in a variety of organisms. Moreover, the combination of transcriptional activator with dead Cas protein can achieve specific regulation of gene expression at the transcription level, which has made important contributions to the development of biotechnology in medical and agriculture. Overexpression of foreign genes is a common method to verify gene function and regulation. However, due to the limitation of vector capacity, it is difficult to achieve overexpression of multiple genes. CRISPR/Cas9 activation system can regulate the expression of multiple genes under the guidance of different guide RNAs to verify gene functions at the regulatory level. This review summarizes the composition of the CRISPR/Cas9 activation system and different activation strategies, and summarizes solutions for excessive activation. It may facilitate the application of CRISPR/Cas9 activation system in genetic improvement of cotton and herbicide resistance research.
Biotechnology ; CRISPR-Cas Systems/genetics* ; Gene Editing ; Phenotype ; RNA, Guide, Kinetoplastida/metabolism*

Objective: To investigate the effects of metformin on mitochondrial pathway of apoptosis and oxidative stress in cell model of nonalcoholic fatty liver disease. Methods: An in vitro cell model of nonalcoholic fatty liver disease was established using 0.6 mmol/L oleic acid to induce lipid accumulation in HepG2 cells. HepG2 cells were divided into control (Con) group, oleic acid (OA) group, and metformin-low (1mmol/L) and high (10mmol/L) dose group. Oil Red O stain was used to detect intracellular lipid droplet distribution. The levels of alanine aminotransferase and aspartate aminotransferase in the culture supernatant were detected by assay kits. DCFH-DA method was used to detect the reactive oxygen species of HepG2 cells. Double staining flow cytometry was used to detect the apoptosis rate of HepG2 cells. Western blot was used to detect caspase-3, B-lymphocyte lymphoma-related protein, B-cell lymphoma 2, and cytochrome c protein. One-way analysis of variance was used to compare the data between groups. Results: Oleic acid-induced HepG2 cells were significantly increased with lipid droplets. Low and high-dose metformin had reduced intracellular lipid droplets accumulation. The effect of metformin in the high-dose group was more significant than that in the low-dose group. Aspartate aminotransferase and alanine aminotransferase in HepG2 cells of OA group were significantly increased, which were (43.41 ± 7.11) U/L and (29.56 ± 4.11) U/L, respectively. The intracellular aspartate aminotransferase and alanine aminotransferase were decreased significantly after the treatment with low and high-dose metformin, which were (32.44 ± 4.08)U/L, (19.31 ± 3.03) U/L, (26.00 ± 3.11) U/L and (15.11 ± 4.11) U/L, respectively and the differences were statistically significant (P < 0.05). DCFH-DA test results showed that the fluorescence intensity of reactive oxygen species in the oleic acid group was 41.21% ± 4.23%, while the fluorescence intensity of reactive oxygen species in the low and high-dose metformin groups were reduced to 27.44% ± 3.91%, and 17.55% ± 5.11%, respectively and the differences between the groups were statistically significant (P < 0.05). The results of flow cytometry analysis showed that the cell apoptosis rate of the OA group was significantly higher than that of the Con group (12.12% ± 0.72% vs. 3.04% ± 0.57%, P < 0.05).The apoptosis rate of HepG2 cells was significantly reduced after metformin treatment at low and high doses (8.71% ± 0.71%, 5.71% ± 0.61%, P < 0.05). Western blot results showed that compared with the Con group, the expressions of B-lymphocyte lymphoma-related protein, cytochrome c, and caspase-3 were increased in the OA group, while the B-cell lymphoma 2 were decreased (P < 0.05). The expression of B-lymphocyte lymphoma-related protein, cytochrome c, and caspase-3 protein in HepG2 cells was decreased after treatment with low and high-dose metformin, while B-cell lymphoma 2 was increased (P < 0.05). Conclusion Metformin can effectively alleviate steatosis and improve the HepG2 function in cell model of nonalcoholic fatty liver disease. The mechanism of metformin may be related to the reduction of oxidative stress injury, the regulation of protein expression related to mitochondrial apoptosis pathway and the inhibition of cell apoptosis.

Objective To analyze the clinical characteristics of structural malformations in one of monochorionic diamnionic twins (MCDA). Methods The clinical data of 77 MCDA patients with structural malformations diagnosed by ultrasound were retrospectively reviewed from January 2012 to May 2017. The distribution of structural malformations, prenatal chromosomal karyotyping and pregnancy outcomes were analyzed. Results (1)Among the 77 MCDA patients with structural malformations, the single malformation accounted for 79％(61/77), the multiple malformations accounted for 21％(16/77). And there were a total of 94 types of malformations, the top three malformations were neurological malformations (32％, 30/94), cardiovascular malformations (29％,27/94) and twin reversed arterial perfusion sequence (TRAPS;10％,9/94). (2)Among the 77 patients with structural malformation, 64 cases (83％, 64/77) were examined for fetal chromosomes, of whom 14 cases (22％,14/64) were examined for fetal chromosomes of both twins, with 1 case (1/14) of discordant fetal chromosome. (3)Among the 77 patients, 4 cases (5％, 4/77) with severe fetal malformations terminated pregnancy. Totally 29 cases (38％, 29/77) with severe malformations were treated with selective fetal reduction, among whom 7 cases (24％, 7/29) experienced unexplained fetal death within 24 hours after the operation;2 cases (7％, 2/29) happened inevitable abortion, and 2 cases (7％, 2/29) underwent unexplained fetal death during the late pregnancy. Of the remaining 44 patients (57％,44/77) with expectant treatment, 13 cases (30％, 13/44) occurred twin transfusion syndrome (Ⅱ-Ⅳ), and were treated with fetoscopic laser occlusion. Eight patients had 2 survival twins, 4 patients delivered 1 survival twin, and 1 patient had dead twins. Conclusions The most common malformations in MCDA twins are the nervous malformations, cardiovascular malformations and TRAPS. The chromosome karyotype of MCDA twins with structural malformations are sometimes discordant, and separate samling of the twins is suggested for prenatal diagnosis. Selective fetal reduction could be given to severe structural malformation in MCDA patients safely and effectively. For non-severe structural malformation in MCDA patients with twin transfusion syndrome, fetoscopic laser occlusion is safe and effective.

Objective To investigate the risk factors of electrocoagulation syndrome after endoscopic submucosal dissection (ESD) in patients with colorectal lesions.Methods Clinical data of 145 patients with colorectal mucosal lesions undergoing ESD in People's Hospital of Wuhan University between September 2010 and September 2015 were retrospectively studied.Results Among 45 patients,post endoscopic submucosal dissection electrocoagulation syndrome (PEECS) was developed in 32 cases (22％).The median age in PEECS group was higher (t =-5.783,P =0.000),the median lesion size was larger(t =-5.590,P =0.000),the median length of hospital stay was longer (t =-6.841,P =0.000) than those in non-PEECS group.Univariate regression analysis showed PEECS was associated with the age,lesion size,lesion location,length of hospital stay,malignant tumor,polyps type,resection modality.Multivariable logistic regression analysis showed that the independent risk factors for the development of electrocoagulation syndrome were age ＞65 year (OR =1.123,95％ CI:1.013-1.244,P =0.027),lesion size ＞ 3.5 cm (OR =1.173,95％ CI:1.015-1.357,P =0.031),malignant tumor (OR =3.498,95 ％ CI:1.460-8.379,P =0.005),hospital stay ＞ 10 d (OR =2.480,95％ CI:1.346-4.569,P =0.004),non-rectal lesions (OR =12.612,95％ CI:3.446-46.157,P =0.000).Conclusion Attention should be paid for colorectal lesion patients with high risk of PEECS,when endoscopic submucosal dissection is performed.

Objective To explore the association between patatin-like phospholipase domaincontaining protein 3 (PNPLA3) gene rs738409 polymorphism and the susceptibility of non-alcoholic fatty liver disease (NAFLD).Methods Data bases were comprehensively searched to retrace all the related studies on the association between PNPLA3 gene rs738409 polymorphism and susceptibility.Of NAFLD,the pooled OR with 95％ CI of the association between PNPLA3 gene rs738409 polymorphism and NAFLD susceptibility were performed using different genetic models.Subgroup analysis based on the source of population and sensitivity analysis was performed to detect the stability of results.Results 28 original studies with 6 216 patients and 8 218 controls were involved in the final combination of data.Findings from the meta-analyses showed that there were strong associations between PNPLA3 gene rs738409 polymorphism and the susceptibility of NAFLD,under different genetic model comparisons [GG vs.CC:OR=2.42,95％CI:1.83-3.21,P＜0.001 ;CG vs.CC:OR=1.28,95％CI:1.15-1.43,P＜0.001 ; CG+GG vs.CC:OR=1.31,95％CI:1.17-1.46,P＜ 0.001 ; GG vs.CC + GC:OR=2.26,95％CI:1.76-2.90,P＜0.001].Similar results were found in both Asian and Caucasian populations.Conclusion Results from the Meta-analysis strongly suggested that there appeared significant association between PNPLA3 gene rs738409 polymorphism and the susceptibility of NAFLD.

Objective To study whether matrix metalloproteinases-9 (MMP)-1562C/T (rs3918242) and MMP-2-1306C/T (rs243865) were associated with the susceptibility on nonalcoholic fatty liver disease (NAFLD) and the interactions between the two factors and central obesity.Methods Genotypes of 545 patients and 636 subjects with NAFLD under control were examined by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP).Unconditional logistic regression (ULR) was performed to assess the NAFLD risk.The geneenvironment interactions on the risk of NAFLD were explored by generalized multifactor dimensionality reduction (GMDR) and ULR methods.Results Results from the case-control analysis indicated that there was an increased risk of developing NAFLD for MMP-9 rs3918242 (TT/CT) genotype carriers,when compared with the non-carriers (CC),with OR=1.67,95％ CI:1.32-2.12,P=0.001;Adjusted OR=1.65,95％CI:1.31-2.01 (P=0.008).However,risk reduction of NAFLD was found when MMP-2 rs243865 (TT/CT) genotype carriers compared with the non-carriers (CC),with OR=0.68,95％CI:0.53-0.86,P=0.001;with adjusted OR=0.66,95％CI:0.49-0.90 (P=0.007).Data from the GMDR showed that gene-environment interaction among rs3918242 and central obesity on the risk of NAFLD might be significant (P=0.001).By using the ULR method,subjects as central obesity-positive but with genotype CT/TT,appeared having 4.50 (95％ CI:2.78-7.17,P =0.007) times risk of NAFLD,when compared to the central obesity-negative subjects with genotype CC after adjusting for the covariates.Conclusion MMP-9 rs3918242,MMP-2 rs243865 were associated with risk of NAFLD while both rs3918242 and central obesity showing synergistic effects on the risk of the NAFLD.

Objective To establish the golden hamster model of buccal squamous carcinoma and observe its biological character-istics .Methods 50 golden hamster were randomly divided into two group :experiment group (n=40) and control group(n=10) . Buccal mucosa of golden hamster were daubed by exposure 4-nitroquinoline-1-oxide (4NQO) in experiment group and tap water in control group .HE staining and immunohistochemistry were used to observe the tissue sample on the 8th and 12th week .The tissue samples of golden hamster buccal-mucosa cancer were used for the in-vitro subculture .Then flat cloning formation rate ,expression of CK and Vim ,and cell karyotype were detected .Results The observations of cell morphology and biology showed that the tissue of buccal squamous carcinoma were conformed to the basic characteristics of squamous carcinoma cell in 26 golden hamster(84 .6% ) after 12 weeks .The positive rate of CK and Vim were 96 .0% by immunohistochemical staining .The Chromosomes were tetraploid karyotype .Conclusion We successfully established the golden hamster model of buccal squamous carcinoma by the daub method of 4NQO .