Objective To assess retinal and choroidal blood flow density in the macular regions of children diagnosed with unilateral low myopia using optical coherence tomography angiography(OCTA).This study aimed to investigate the clinical significance of these mea-surements.Methods A cross-sectional study was conducted on 90 eyes of 45 children with monocular myopia and adolescents aged 8 to 14 years who visited the outpatient department of the Ophthalmology of Dalian Third People's Hospital between June 2022 and February 2023.Optometry was performed after a 1%cyclopentolate cycloplegic muscle paralysis.Eyes with spherical equivalent(SE)-3.00 D to-0.50 D were included in the myopia group,whereas those with SE-0.25 D to＜+2.00 D were placed in the non-myopia group.The Master system was used to measure axial length(AL)and corneal curvature radius(CR),and to calculate AL/CR.Heidelberg spectral-domain optical coherence tomography(SD-OCT)was used to perform horizontal linear scanning of the macular area to obtain subfoveal choroidal thickness(SFCT).The OCTA module was used to obtain 3 mm×3 mm choroidal blood flow images,which were imported into ImageJ graphics processing software to obtain the blood flow densities of the superficial choroidal plexus(SCP),deep choroidal plexus(DCP),choroidal capillary(CC),and foveal avascular zone(FAZ).Pearson's correlation was used to examine the correlations between each blood flow parameter and age,AL,CR,AL/CR,and SFCT.Results The SE and SFCT of the myopia group were smaller(P＜0.05)than those of the non-myopia group,whereas the AL and AL/CR were significantly larger(P＜0.05)than those of the non-myopia group.The DCP blood flow density in the myopia group was significantly lower than that in the non-myopia group(P＜0.01).There was no statistically sig-nificant difference between the residual blood flow parameters of the myopia and non-myopia groups(P＞0.05).The Pearson's correlation analysis indicated that the SCP and DCP blood flow densities in the myopia group were positively correlated with SE(r= 0.611,0.731,P＜0.05),negatively correlated with AL(r=-0.568,-0.712,P＜0.05),and negatively correlated with AL/CR(r=-0.557,-0.564,P＜0.05).The SCP and DCP blood flow densities were negatively correlated with AL/CR in the non-myopia group(r=-0.615,-0.656,P＜0.05).The CC density and FAZ area in the two groups did not correlate with age,SE,AL,CR,AL/CR,or SFCT(P＞0.05).Conclusion Com-pared to non-myopic eyes,the eyes of children with mild monocular myopia had lower DCP blood flow density.Moreover,retinal blood flow density in myopic eyes was correlated with SE,AL,and AL/CR,whereas retinal blood flow density in non-myopic eyes was only correlated with AL/CR.

BACKGROUND: It has been pointed out that perioperative hypothermia can increase the incidence of coagulation, acidosis, stroke, sepsis, pneumonia and myocardial infarction, so it is of great significance to monitor and maintain normal body temperature during perioperative period. OBJECTIVE: To design a medical carbon fiber thermostatic heating pad to prevent perioperative hypothermia and reduce complications. METHODS: The carbon fiber heating technology and medical equipment standard are combined and integrated into many advanced technologies. The system mainly consisted of power supply conversion, operation system, computer control system, PWM control and output, various heating pads and temperature controlling measurement system. A total of 200 patients undergoing epidural anesthesia in Zhengzhou First People's Hospital were randomly divided into two groups: the observation group (n=100) was treated with the medical carbon fiber thermostatic heating pad (adjusting temperature 38-40 oC), and the control group (n=100) with common quilt. The body temperature and shivering were monitored before operation, 10, 30 and 60 minutes after anesthesia, and 2 hours after operation. RESULTS AND CONCLUSION: (1) The heating pad had the characteristics of explosion proof, power purification, shielding isolation, output protection, computer control, and PWM modulation. (2) In clinical application, there was no skin irritation and skin allergy reaction in the observation group. (3) During operation, the body temperature of the observation group was relatively stable, and there was no significant difference in the body temperature in the observation group before and at 2 hours after operation (P> 0.05). However, the fluctuation of body temperature in control group was visible and showed a downward trend, and the body temperature in the control group showed a significant difference before and 2 hours after operation (P < 0.05). The body temperature of 10, 30, 60 minutes after anesthesia and 2 hours after operation was significantly higher in the observation group than the control group (P < 0.05). (4) The postoperative incidence of shivering in the control group was significantly higher than that in the observation group (18％ vs. 5％, P < 0.05). To conclude, the medical carbon fiber thermostatic heating pad is advanced in technology, safe and reliable in use, providing a new way for the prevention of perioperative shivering.

Objective: To monitor the antimicrobial resistance and drug-resistance genes of Yersinia enterocolitis, Y. intermedia and Y. frederiksenii recovered from retailed fresh poultry of 4 provinces of China. Methods: The susceptibility of 25 isolated Yersinia spp. to 14 classes and 25 kinds of antibiotics was determined by broth microdilution method according to CLSI (Clinical and Laboratory Standards Institute). The antibiotic resistance genes were predicted with antibiotic resistance genes database (ARDB) using whole genome sequences of Yersinia spp. Results: In all 22 Y. enterocolitis tested, 63.7% (14 isolates), 22.8% (5 isolates), 4.6% and 4.6% of 1 isolates exhibited the resistance to cefoxitin, ampicillin-sulbactam, nitrofurantoin and trimethoprim-sulfamethoxazole, respectively. All the 25 isolates were multi-drug resistant to more than 3 antibiotics, while 64.0% of isolates were resistant to more than 4 antibiotics. A few Y. enterocolitis isolates of this study were intermediate to ceftriaxone and ciprofloxacin. Most Yersinia spp. isolates contained antibiotic resistance genes mdtG, ksgA, bacA, blaA, rosAB and acrB, and 5 isolates recovered from fresh chicken also contained dfrA1, catB2 and ant3ia. Conclusion The multi-drug resistant Yersinia spp. isolated from retailed fresh poultry is very serious in the 4 provinces of China, and their contained many kinds of drug-resistance genes.

Objective: To obtain the serotype diversity and antimicrobial resistance of Salmonella isolates recovered from retail chicken carcasses for sale in six regions of China. Methods: From August 2010 to March 2012, each month 20 retail chicken carcasses including freshly slaughtered, chilled and frozen samples were collected from supermarkets and farmer's markets in 7 monitoring sites in Beijing, Jilin province, Inner Mongolia Autonomous, Shanxi province, Jiangsu province and Guangdong province, respectively. Samples were routinely collected for 12 months for each site. 1 680 chicken carcasses were collected in total and 2 629 Salmonella strains were isolated by PCR and biochemical method. Luminex xMAP method and classical slide agglutination method were carried out to determine isolates' serotypes. Minimal inhibitory concentrations (MICs) of 10 classes of antimicrobials including 14 agents were determined using broth micro-dilution method. Mocular methods were used to determine antimicrobial resistance genes of CIP-CTX-CT co-resistant isolates. Results: In all, 2 629 Salmonella isolates, there were 17 seorgroups and 58 serotypes, B and D1 were the dominant serogroups with rates of 34.7% (n=913) and 31.0% (n=815), Enteritidis (30.8%, n=810), Indiana (17.6%, n=463), Infantis (10.6%, n=278) were the top three serovars. We found 224 CIP-CTX co-resistant S. Indiana containing 3 colistin resistant strains, one of them carrying mcr-1 gene and being ESBLs positive, which demonstrated a nine multi drug resistance against 11 antimicrobials tested. Conclusion These data began to describe the complicated serovar diversity and heavy antimicrobial resistance of Salmonella isolates recovered from retail chicken carcasses in six regions of China. The findings highlight the emergence of ciprofloxacin and cefotaxime co-resistant S. Indiana and also a mcr-1 positive S. Indiana with heavy multi drug resistance.

Objective The study aimed to construct a composite score method based on multidimensional quality indi-cators and conduct simulation trials to validate the method. Besides,the quality of breast cancer care for both hospitals and sur-geons was evaluated by the method. Methods The two-parameter logistic latent variable model was constructed as measure-ment model;the latent variables in the measurement model were further incorporated into multilevel structural model as depend-ent variables and one pseudo level was designed for representing multiple latent variables. MCMC method was used to estimate model parameters. Three level and two-dimensional latent variable model was used to analyze the actual data. Results The sim-ulation study showed that the number of quality indicators and surgeons should not be less than 20 to obtain efficient estimate of quality of care;the multilevel and multidimensional latent variable model was applied to analyze the data;surgeons and hospitals who provided superior quality of breast cancer diagnosis and operative procedure were obtained. Conclusion The newly con-structed multilevel and multidimensional latent variable model could effectively address the hieratical structure in quality of care data as well as the multidimensional nature of quality of care,thus,the model can be used to comprehensively and rationally as-sess the quality of care;comprehensive evaluation of quality of care provided ground for linking the ranking of hospitals and per-formance appraisal of surgeons to the quality of care.

Objective The study aimed to construct a composite score method based on multidimensional quality indi-cators and conduct simulation trials to validate the method. Besides,the quality of breast cancer care for both hospitals and sur-geons was evaluated by the method. Methods The two-parameter logistic latent variable model was constructed as measure-ment model;the latent variables in the measurement model were further incorporated into multilevel structural model as depend-ent variables and one pseudo level was designed for representing multiple latent variables. MCMC method was used to estimate model parameters. Three level and two-dimensional latent variable model was used to analyze the actual data. Results The sim-ulation study showed that the number of quality indicators and surgeons should not be less than 20 to obtain efficient estimate of quality of care;the multilevel and multidimensional latent variable model was applied to analyze the data;surgeons and hospitals who provided superior quality of breast cancer diagnosis and operative procedure were obtained. Conclusion The newly con-structed multilevel and multidimensional latent variable model could effectively address the hieratical structure in quality of care data as well as the multidimensional nature of quality of care,thus,the model can be used to comprehensively and rationally as-sess the quality of care;comprehensive evaluation of quality of care provided ground for linking the ranking of hospitals and per-formance appraisal of surgeons to the quality of care.

Objective To quantify the correlations between Elekta XVI cone beam CT dose and various scanning protocols,providing mathematical models to assess the protocol-dependency of imaging dose during imnage guided radiotherapy.Methods Based on standard protocols and various combinations of kVp and mA on an XVI mounted on an Elekta Versa HD accelerator,the air KERMA was measured at various positions in a standard PTW CTDI body phantom using calibrated PTW 30009 kV chamber and UNIDOS webline electrometer.Weighted CT dose index (CTDIw) was computed thereafter.SigmaPlot 10.0 was used to fit the measurements against mA and/or kVp yielding empirical functions.Results Under standard protocols,the CTDIw of Varian OBI was only 11.23％ (chest) and 9.15％ (pelvis) of Elekta XVI.Using the default and other 4 investigated kVp values,the central and peripheral KERMA were both proportional to mA,and vet the slope value a varied dramatically from 0.479 to 6.679.Major affecting factors included kVp settings,measurement locations,and dosimetric mnetrics,etc.None linear regressions were used to fit kVp against KERMA at various locations and CTDIw (R2 ＞ 0.997).The differences between all coefficients were statistically significant (P ＜ 0.05).The impact of changing both mA and kVp on the dose to phantom center can be described as mGy =(5.917-0.197 ×kVp+0.002 × kVp2-5.063 × 10-6 × kVp3) × mA.Conclusions Imaging dose of Elekta XVI is strongly dependent on scanning paraneters.The proposed mathematical models can be used as efficient and robust indicators of such dependency.

Objective : To explore the correlation between oral mucosal lichen planus and Helicobacter pylori infection by analyzing the infection status of Helicobacter pylori in patients with oral mucosal lichen planus. Methods: 14C- urea breath test was done in 69 patients with oral lichen planus and 28 patients with chronic inflammation of oral mucosa. Detection of serum anti Helicobacter pylori antibody was done in 32 patients (23 with oral lichen planus and 9 with chronic inflammation of oral mucosa) at the same time. Results : The positive rate of 14C-urea breath test was 68.12% in patients with oral lichen planus and 46.43% in chronic inflammation of oral mucosa. There was significant difference between the 2 groups (χ2=3.970, P=0.046). The positive rate of anti Helicobacter pylori antibody was 52.17% in patients with oral lichen planus and 22.22% in chronic inflammation of oral mucosa, and there was no significant difference between the 2 groups (χ2=2.358, P=0.125). Conclusion The prevalence of Helicobacter pylori infection in patients with oral lichen planus is higher, and there is a relevance between oral lichen planus and Helicobacter pylori infection.

OBJECTIVETo evaluate the quality and clinical applicability of pyrosequencing assay kit for detecting hepatitis B virus resistance (HBV DRT).

METHODSSerial dilutions of the International Standard for HBV DNA were used to test the detection limit of the PCR for HBV DRT. Plasmids containing the either a wild-type (WT) copy or one of 10 mutant (MT) copies of the HBV RT gene were used to prepare a series of samples with various mutation ratios. To construct the linear relationship between the true mutation rate and the detected mutation rate, each sample was repeated at least 10 times. A total of 102 clinical samples were analyzed by Sanger sequencing and retested by the PCR for HBV DRT to determine the concordance of these two methods.

RESULTSThe lower detection limit of the PCR for HBV DRT was 50 IU/ml. Except for the RT236 MT, the correlation between the true mutation rate and the detected mutation rate for the other nine resistance-related mutation sites were excellent, with R² more than 0.98 (P less than 0.001). Among the 102 clinical samples, four were not amplified successfully by PCR. The results were significantly different between the PCR for HBV DRT method and the Sanger sequencing method (x² = 71.2, P less than 0.001), and concordance was observed for 897/969 (92.6%) amino acid positions in 98 samples. Concordant results were achieved in 46/98 (46.9%) samples at all 10 mutation sites. For detection of a single mutation site, concordance rates ranged from 71.5% to 100% at the 10 mutation sites, respectively. Analysis of discordant samples showed that in 87.5% (63/72), Sanger sequencing detected WT and the PCR for HBV DRT detected WT/MT. In 5.6% (4/72) of samples, Sanger sequencing detected WT/MT and the PCR for HBV DRT detected WT. In the remaining 6.9% (5/72) of samples, Sanger sequencing detected WT but PCR for HBV DRT detected MT.

CONCLUSIONThe PCR for HBV DRT showed high sensitivity and accuracy in detecting antiviral drug-resistant mutations. The method is superior to Sanger sequencing for detecting minor mutations and can be used for early detection of a resistance mutation.

Cerebral ischemia-induced inflammatory cascade reaction may aggravate nerve tissue damage and destroy blood-braln barrier, and angiogenesis after ischemia can improve nerve function. Inhibiting inflammatory response after stroke, promoting angiogenesis and protecting blood-braln may reduce nerve tissue damage and promote recovery of neurological function. Monocyte chemotactic protein 1-induced protein inhibits inflammatory signaling pathways through degradating proinflammatory cytokine mRNA. Its unique biological characteristics also suggest that it has the potential protective effect in cerebral ischemia. This article focuses on the roles of monocyte chemotactic protein 1-induced protein in cerebral ischemia.