Objective To investigate the detection rate,epidemiology and resistance mechanism of methicil-lin-resistant Staphylococcus aureus(MRSA)in a hospital in recent 5 years.Methods A total of 762 strains of non repetitive Staphylococcus aureus detected from 2016 to 2020 in a hospital were collected retrospectively.Methicillin-sensitive Staphylococcus aureus(MSSA)was 392 strains(MSSA group)and 370 strains caused by MRSA(MRSA group),and 95 strains of MRSA isolated in 2020 were further used for resistance mechanism.Staphylococcus aureus was identified and tested for drug sensitivity by Vitek 2 automatic microbial system.Molecular epidemiological typing was determined by multilocus sequence typing.The biofilm formation was performed by crystal violet staining.PCR amplification was used to detect drug resistance genes,virulence genes and biofilm related genes,and logistic regression analysis was used to investigate the independent risk factors of its occurrence.Results The detection rate of MRSA in past five years was 48.56％,mainly was from pus samples and secretion samples(38.38％,33.51％respectively).MRSA was found in the general sur-gery(18.65％)and otorhinolaryngology(12.70％).ST88 was the most common multilocus sequence typing(37.89％),and followed by ST951(24.21％).Moderate biofilm formation was the most common,accounting for 74.73％.Multivariate regression analysis showed that compared with MSSA group,hypoproteinemia,en-docrine system diseases,wound infection and history of antibiotic use within six months were the independent risk factors for infection in MRSA group.Compared with the control group,hospital transfer,wound infection and tumor were independent risk factors for infection in MRSA group(P＜0.05).Conclusion The detection rate of MRSA in a hospital is high,and the carrying rate of various drug-resistant genes is high.The hospital should pay attention to the prevalence of MRSA and related risk factors,so as to prevent it early.

Objective To establish a mouse model of type Ⅰ tricho-hepato-enteric syndrome(THES)induced by Ttc37 deficiency.Methods Ttc37 flox strain was established by site-specifically inserted loxP sites into Ttc37 gene via CRISPR/CAS9 technology.Ubiquitously expressed CAG-Cre was introduced for all-tissue removal of Ttc37 in Ttc37flox/flox;CAG-Cre mice.The knock-out effect was confirmed by fluorescence quantitative PCR and Western blot.Phenotypic evaluations were conducted in 8-week-old mice including hematoxylin-eosin staining of skin,spleen,liver,bladder,and gastrointestinal tract(GI),serum enzyme activity assay of aspartate aminotransferase(AST)and alanine aminotransferase(ALT),measurement of serum hemoglobin level,and ELISA for IgG and IgM level upon antigen immunization.Results Similar to type Ⅰ THES patients,Ttc37flox/flox;CAG-Cre mice exhibited impaired development of hair shaft,epidermis,B cell and eyes,while liver,GI,bladder and serum hemoglobin level seemed normal under unstressed condition.Conclusion A novel mouse model of typeⅠ THES was constructed successfully,which was applicable for pathological study.

Quadratus lumborum block(QLB)is a regional anesthesia technique that provides sen-sory and sympathetic nerves block of the unilateral trunk and lower limb by an injection of local anesthetic into the fascia space around the quadratus lumborum.At present,ultrasound-guided QLB is widely used in postoperative analgesia in abdominal and lower limb surgery with satisfied analgesia efficacy.This article will review the anatomical basis,mechanisms,puncture approaches,local anesthetic selection,clinical applica-tion and complications of QLB.

Objective:To analyze the association between waist circumference (WC) and ischemic stroke (IS).Methods:The data for the present study were from the prospective cohort study of China Kadoorie Biobank in Qingdao. Using baseline information and IS events of the participants, the Cox proportional hazard regression model and restricted cubic spline (RCS) were used to analyze the association between WC and IS.Results:A total of 33 355 participants were included in the study, with 302 008.88 person-years of follow-up. A total of 1 093 new cases of IS were observed. Multivariate Cox proportional hazard regression model analysis showed that compared to the respondents with normal WC (male <85.0 cm, female <80.0 cm), respondents with excessive WC (male ≥85.0 cm, female ≥80.0 cm) had a 78% higher risk of IS incidence [hazard ratio( HR)=1.78, 95% CI: 1.51-2.10], and the risk increased by 72% ( HR=1.72, 95% CI: 1.40-2.12) and 83% ( HR=1.83, 95% CI: 1.40-2.39) in men and women. According to the RCS, the increase in WC and the risk of IS showed an "S" trend of nonlinear dose-response relationship. Conclusions:The risk of IS would increase with the WC. Keeping a normal WC is important for preventing IS.

Objective To investigate the application value of 3.0T MR apparent diffusion coefficient(ADC)in prognosis and pathological types of endometrial carcinoma(EC).Methods A total of 114 EC patients were retrospectively selected,and the ADC values of different pathological types were compared.The correlation between ADC and EC prognosis was analyzed by dividing the ADC quintile(Q1-Q5).Results The ADC parameters of EC patients with different pathological types were significantly different(P＜0.05).With the increase of ADC value,the correlation effect size between ADC and EC prognosis also increased(Ptrend＜0.001).ADC had a better predictive effect on EC prognosis.International Federation of Gynecology and Obstetrics(FIGO)stage,myographic invasion and ADC value had interaction with EC prognosis(P interaction＜0.05).Conclusion ADC can be used to distinguish the patho-logical types of EC.Also,ADC is significantly associated with EC prognosis while its correlation effect size increases with the increase of ADC value.ADC value interacted with FIGO stage,as well as with the degree of myographic invasion in predicting EC prognosis.

Objective:To investigate the early clinical characteristics of elderly patients with severe burns and the risk factors on prognosis.Methods:This study was a retrospective case series study. Clinical data of 124 elderly patients with severe burns who met the inclusion criteria and were admitted to the 12 hospitals from January 2015 to December 2020 were collected, including 4 patients from the Fourth People's Hospital of Dalian, 5 patients from Fujian Medical University Union Hospital, 22 patients from Guangzhou Red Cross Hospital of Jinan University, 5 patients from Heilongjiang Provincial Hospital, 27 patients from the First Affiliated Hospital of Naval Medical University, 9 patients from the First Affiliated Hospital of Nanchang University, 10 patients from Affiliated Hospital of Nantong University, 9 patients from Tongren Hospital of Wuhan University & Wuhan Third Hospital, 12 patients from the 924 th Hospital of PLA, 6 patients from Zhangjiagang First People's Hospital, 4 patients from Taizhou Hospital of Zhejiang Province, and 11 patients from Zhengzhou First People's Hospital. The patients' overall clinical characteristics, such as gender, age, body mass index, total burn area, full-thickness burn area, inhalation injury, causative factors, whether combined with underlying medical diseases, and admission time after injury were recorded. According to the survival outcome within 28 days after injury, the patients were divided into survival group (89 cases) and death group (35 cases). The following data of patients were compared between the two groups, including the basic data and injuries (the same as the overall clinical characteristics ahead); the coagulation indexes within the first 24 hours of injury such as prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time, D-dimer, fibrinogen degradation product (FDP), international normalized ratio (INR), and fibrinogen; the blood routine indexes within the first 24 hours of injury such as white blood cell count, platelet count, neutrophil-to-lymphocyte ratio, monocyte count, red blood cell count, hemoglobin, and hematocrit; the organ function indexes within the first 24 hours of injury such as direct bilirubin, total bilirubin, urea, serum creatinine, aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, blood glucose, triglyceride, total cholesterol, alkaline phosphatase, creatine kinase, electrolyte indexes (potassium, sodium, chlorine, calcium, magnesium, and phosphorus in blood), uric acid, myoglobin, and brain natriuretic peptide; the infection and blood gas indexes within the first 24 hours of injury such as procalcitonin, C-reactive protein, pH value, oxygenation index, base excess, and lactate; treatment such as whether conducted with mechanical ventilation, whether conducted with continuous renal replacement therapy, whether conducted with anticoagulation therapy, whether applied with vasoactive drugs, and fluid resuscitation. The analysis was conducted to screen the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns. Results:Among 124 patients, there were 82 males and 42 females, aged 60-97 years, with body mass index of 23.44 (21.09, 25.95) kg/m 2, total burn area of 54.00% (42.00%, 75.00%) total body surface area (TBSA), and full-thickness burn area of 25.00% (10.00%, 40.00%) TBSA. The patients were mainly combined with moderate to severe inhalation injury and caused by flame burns. There were 43 cases with underlying medical diseases. The majority of patients were admitted to the hospital within 8 hours after injury. There were statistically significant differences between patients in the 2 groups in terms of age, total burn area, full-thickness burn area, and inhalation injury, and PT, APTT, D-dimer, FDP, INR, white blood cell count, platelet count, urea, serum creatinine, blood glucose, blood sodium, uric acid, myoglobin, and urine volume within the first 24 hours of injury (with Z values of 2.37, 5.49, 5.26, 5.97, 2.18, 1.95, 2.68, 2.68, 2.51, 2.82, 2.14, 3.40, 5.31, 3.41, 2.35, 3.81, 2.16, and -3.82, respectively, P<0.05); there were statistically significant differences between two groups of patients in whether conducted with mechanical ventilation and whether applied with vasoactive drugs (with χ2 values of 9.44 and 28.50, respectively, P<0.05). Age, total burn area, full-thickness burn area, serum creatinine within the first 24 hours of injury, and APTT within the first 24 hours of injury were the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns (with odds ratios of 1.17, 1.10, 1.10, 1.09, and 1.27, 95% confidence intervals of 1.03-1.40, 1.04-1.21, 1.05-1.19, 1.05-1.17, and 1.07-1.69, respectively, P<0.05). Conclusions:The elderly patients with severe burns had the injuries mainly from flame burns, often accompanied by moderate to severe inhalation injury and enhanced inflammatory response, elevated blood glucose levels, activated fibrinolysis, and impaired organ function in the early stage, which are associated with their prognosis. Age, total burn area, full-thickness burn area, and serum creatinine and APTT within the first 24 hours of injury are the independent risk factors for death within 28 days after injury in this population.

Objective To investigate the disease spectrum and pathogenic genes of inherited metabolic disorder(IMD)among neonates in Gansu Province of China.Methods A retrospective analysis was conducted on the tandem mass spectrometry data of 286 682 neonates who received IMD screening in Gansu Provincial Maternal and Child Health Hospital from January 2018 to December 2021.A genetic analysis was conducted on the neonates with positive results in tandem mass spectrometry during primary screening and reexamination.Results A total of 23 types of IMD caused by 28 pathogenic genes were found in the 286 682 neonates,and the overall prevalence rate of IMD was 0.63‰(1/1 593),among which phenylketonuria showed the highest prevalence rate of 0.32‰(1/3 083),followed by methylmalonic acidemia(0.11‰,1/8 959)and tetrahydrobiopterin deficiency(0.06‰,1/15 927).In this study,166 variants were identified in the 28 pathogenic genes,with 13 novel variants found in 9 genes.According to American College of Medical Genetics and Genomics guidelines,5 novel variants were classified as pathogenic variants,7 were classified as likely pathogenic variants,and 1 was classified as the variant of uncertain significance.Conclusions This study enriches the database of pathogenic gene variants for IMD and provides basic data for establishing an accurate screening and diagnosis system for IMD in this region.

Objective To investigate the genetic causes of auditory neuropathy with optic atrophy in a family.Methods The proband's medical history and family history were inquired in detail,and relevant clinical examina-tions were performed to confirm the diagnosis of auditory neuropathy with optic atrophy,and the genetic pedigree of the family was drawn.Peripheral blood of proband(Ⅲ-7)was collected for whole exome sequencing,and the patho-genicity of the detected mutations were interpreted.Blood samples of proband's wife(Ⅲ-8),eldest daughter(Ⅳ-7),second daughter(Ⅳ-9)and son(Ⅳ-10)were tested for mutation sites by Sanger sequencing.Combined with clinical manifestations and examination results,the family was studied.Results The genetic pattern of this family was autosomal dominant.The proband showed decreased visual acuity at the age of 19,bilateral sensorineural deaf-ness at the age of 30,and decreased speech recognition rate.Among 20 members of the family of 5 generations,10(2 deceased)showed similar symptoms of hearing and visual impairment.Proband(Ⅲ-7),eldest daughter(Ⅳ-7)and son(Ⅳ-10)underwent relevant examination.Pure tone audiometry showed bilateral sensorineural deafness.ABR showed no response bilaterally.The 40 Hz AERP showed no response in both ears.OAE showed responses in some or all of the frequencies.No stapedial reflex was detected.The eye movement of Ⅲ-7 and Ⅳ-10 were reasona-ble in all directions,and color vision was normal.Ocular papilla atrophy was observed in different degrees in fundus examination.OCT showed thinning of optic disc nerve fibers in both eyes,and visual evoked potential showed pro-longed P100 wave peak.They were diagnosed as hereditary auditory neuropathy with optic atrophy.A mutation of the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)at a pathogenic locus on chromosome 3 was detected by whole exon detection in Ⅲ-7.The results of generation sequencing analysis showed that the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)mutation of chromosome 3 was also found in Ⅳ-7 and Ⅳ-10.Meanwhile,the gen-otypes of Ⅲ-8 and Ⅳ-9 were wild homozygous,that is,no mutation occurred.Conclusion The OPA1 c.1334G＞A(p.Arg445His,NM_015560.2)mutation site might be the pathogenic mutation in this family.

Objective To compare effectiveness between the modified and traditional pressure-overload myocardial hypertrophy(POMH) model by abdominal aorta coarctation (AAC) method. Methods Totally 45 rats were divided into three groups(n = 15 per group), sham group, traditional group, and modified group. In the traditional group, the diameter ol the abdominal aorta was narrowed to 0. 70 mm through a midline incision for 4 weeks; in the modified group, the diameter of the abdominal aorta was narrowed above the left kidney to 0. 45 mm for 1 week, and then the narrowing was lifted postoperatively. The cardiac index, heart weight (HW) /body weight (BW) and left ventricular index, left ventricular weight (LVW)/BW were measured from the heart specimens, and the cross-sectional area of cardiac myocytes, myocardial collagen area, and myocardial collagen area Iraction were measured in the pathological sections by HE staining and Masson staining. Results Compared with the sham group, the differences in end-systolic interventricular septum thickness (IVSs), left ventricular end-systolic posterior wall thickness (LVPWs), HW/BW, LVW/BW, cardiomyocyte cross-sectional area, myocardial collagen area, myocardial collagen area fraction, and brain natriuretic peptide (BNP) expression levels were statistically significant (P<0. 05) in the modilied and traditional groups of rats. The differences in these indices were not statistically significant between the modified and traditional groups (P>0. 05). Conclusion The modified abdominal aortic constriction method used in this experiment is time-saving, stable, homogeneous and easy to replicate, and is a more ideal approach to establish a rat model of POMH.

The Flash radiotherapy(Flash-RT),which is the key breakthrough in the basic field of radiotherapy technique,which is expected to cause a new major transformation in the field of radiotherapy.In this paper,we reviewed the latest research advances of the application and the mechanism exploration of Flash-RT in tumor treatment.Current studies have found that both the Flash-RT with electron beams and photon and the Flash-RT with proton can reduce injury of normal tissue than radiotherapy with conventional dose-rate,but the relevant mechanisms are not yet clearly understood,which includes but not limited to oxygen depletion,DNA damage,cellular senescence,apoptosis and immune response.The difference of Flash-RT injury between tumor tissue and normal tissue further reduces the limitations of radiotherapy,and reduces the adverse reaction and complication compared with conventional radiotherapy,which has wide application prospects.