[Clinical features of post-neurosurgical bacterial meningitis in children]

Objective: To understand the characteristics of bacterial meningitis after pediatric neurosurgical procedures. Methods: This was a retrospective observational study. From January 2016 to December 2022, 64 children diagnosed with post-neurosurgical bacterial meningitis based on positive cerebrospinal fluid (CSF) culture in Department of Neurosurgery of Shanghai Children's Medical Center were selected as the study population. The clinical characteristics, onset time, routine biochemical indexes of cerebrospinal fluid before anti infection treatment, bacteriology characteristics and sensitivity to antibiotics of bacteria cultured from cerebrospinal fluid were analyzed. Based on the CSF culture results, the patients were divided into the Gram-positive bacteria infection group and the Gram-negative bacteria infection group. The clinical characteristics of the two groups were compared using t-tests or Wilcoxon rank-sum tests, and chi-square tests. Results: There were 64 children,42 boys and 22 girls, with onset age of 0.83 (0.50, 1.75) years. Seventy cases of post-neurosurgical bacterial meningitis occurred in the 64 children, of which 15 cases (21%) in spring, 23 cases (33%) in summer, 19 cases (27%) in autumn, and 13 cases (19%) in winter. The time of onset was 3.5 (1.0, 10.0) months after surgery; 15 cases (21%) occurred within the first month after the surgery, and 55 cases (79%) occurred after the first month. There were 38 cases (59%) showing obvious abnormal clinical manifestations, fever 36 cases (56%), vomiting 11 cases (17%). Forty-eight cases (69%) were caused by Gram-positive bacteria, with Staphylococcus epidermidis 24 cases; 22 cases (31%) were caused by Gram-negative bacteria, with Acinetobacter baumannii the prominent pathogen 7 cases. The Gram-positive bacterial infection was more common in summer than the Gram-negative bacterial infection (20 cases (42%) vs. 3 cases (14%), χ²=5.37, P=0.020), while the Gram-negative bacterial infection was more in autumn and within the first month after surgery than the Gram-positive bacterial infection (11 cases (50%) vs. 8 cases (17%), 15 cases (67%) vs. 5 cases (33%), χ²=8.48, 9.02; P=0.004, 0.003). Gram-positive bacteria resistant to vancomycin and Acinetobacter baumannii resistant to polymyxin were not found. However, Acinetobacter baumannii showed only 45% (10/22) susceptibility to carbapenem antibiotics. Conclusions: The clinical presentation of post-neurosurgical bacterial meningitis in children is atypical. Gram-positive bacteria are the main pathogens causing post-neurosurgical bacterial meningitis; Gram-negative bacterial meningitis are more likely to occur in autumn and within the first month after surgery. Acinetobacter baumannii has a high resistance rate to carbapenem antibiotics, which should be taken seriously.

[Expert consensus on late stage of critical care management]

We wished to establish an expert consensus on late stage of critical care (CC) management. The panel comprised 13 experts in CC medicine. Each statement was assessed based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principle. Then, the Delphi method was adopted by 17 experts to reassess the following 28 statements. (1) ESCAPE has evolved from a strategy of delirium management to a strategy of late stage of CC management. (2) The new version of ESCAPE is a strategy for optimizing treatment and comprehensive care of critically ill patients (CIPs) after the rescue period, including early mobilization, early rehabilitation, nutritional support, sleep management, mental assessment, cognitive-function training, emotional support, and optimizing sedation and analgesia. (3) Disease assessment to determine the starting point of early mobilization, early rehabilitation, and early enteral nutrition. (4) Early mobilization has synergistic effects upon the recovery of organ function. (5) Early functional exercise and rehabilitation are important means to promote CIP recovery, and gives them a sense of future prospects. (6) Timely start of enteral nutrition is conducive to early mobilization and early rehabilitation. (7) The spontaneous breathing test should be started as soon as possible, and a weaning plan should be selected step-by-step. (8) The waking process of CIPs should be realized in a planned and purposeful way. (9) Establishment of a sleep-wake rhythm is the key to sleep management in post-CC management. (10) The spontaneous awakening trial, spontaneous breathing trial, and sleep management should be carried out together. (11) The depth of sedation should be adjusted dynamically in the late stage of CC period. (12) Standardized sedation assessment is the premise of rational sedation. (13) Appropriate sedative drugs should be selected according to the objectives of sedation and drug characteristics. (14) A goal-directed minimization strategy for sedation should be implemented. (15) The principle of analgesia must be mastered first. (16) Subjective assessment is preferred for analgesia assessment. (17) Opioid-based analgesic strategies should be selected step-by-step according to the characteristics of different drugs. (18) There must be rational use of non-opioid analgesics and non-drug-based analgesic measures. (19) Pay attention to evaluation of the psychological status of CIPs. (20) Cognitive function in CIPs cannot be ignored. (21) Delirium management should be based on non-drug-based measures and rational use of drugs. (22) Reset treatment can be considered for severe delirium. (23) Psychological assessment should be conducted as early as possible to screen-out high-risk groups with post-traumatic stress disorder. (24) Emotional support, flexible visiting, and environment management are important components of humanistic management in the intensive care unit (ICU). (25) Emotional support from medical teams and families should be promoted through"ICU diaries"and other forms. (26) Environmental management should be carried out by enriching environmental content, limiting environmental interference, and optimizing the environmental atmosphere. (27) Reasonable promotion of flexible visitation should be done on the basis of prevention of nosocomial infection. (28) ESCAPE is an excellent project for late stage of CC management.

[Status of personal information sharing on HIV between sexual partners among men who have sex with men who met casual sexual partners on the internet in Zhejiang province]

Objective: To identify the status and determinants of sharing personal HIV information with sexual partners among men who have sex with men (MSM) meeting their casual sexual partners on the internet. Methods: A cross-sectional study was conducted in five cities (Hangzhou, Ningbo, Wenzhou, Taizhou and Shaoxing) in Zhejiang province. The recruitment was enrolled by MSM social organization and in voluntary counseling and testing clinics, with a sample size of 793. A self-designed network questionnaire collected essential characteristics, HIV knowledge, sexual behavior, and sharing personal HIV status. SPSS 20.0 software was used for statistical analysis. Results: Among 767 MSM enrolled 302 MSM who reported finding casual sexual partners on the internet were enrolled in the analysis. MSM reported finding casual partners on the internet only, finding sexual partners online and in places were 62.6% (189/302) and 37.4% (113/302), respectively. Among those reporting web-based sexual behavior in the last six months, 54.6% (165/302) informed their partners of their HIV status, 49.2% (146/297) inquired about HIV status, and 42.9% (82/191) knew HIV status before sex intercourse, 75.8% (113/149) reported consistent condom use with HIV negative partners. The multivariable logistic regression analysis showed that related factors of inconsistent inquired HIV status of partners included 25-34 years old (aOR=2.17, 95%CI: 1.20-3.91), >2 partners on the internet in the last six months (aOR=2.13, 95%CI: 1.27-3.57), low-risk perception of HIV infection with online partners (aOR=1.96, 95%CI:1.14-3.35), numbers of HIV testing >1 times (aOR=0.38, 95%CI: 0.22-0.66). Conclusions: The willingness to know the HIV status of partners among MSM who met sexual partners on the internet was high but with a low rate of knowing their sex partner's HIV status in Zhejiang province. However, the successful implementation proportion was low. Therefore, it is necessary to pay attention to people who are elderly, with less conscience about the risk of the sex partners on the internet, have more sex partners, and have received few HIV tests. In addition, peer education was needed to promote related intervention programs.

Visible imaging system with changeable field of view on the HL-2A tokamak

A new visible imaging system characterizing a flexible optical design and delivering high resolution frames is established on the HL-2A tokamak. It features a modular configuration, consisting of a front-end imaging lens, a set of bilateral telecentric relay lenses, and a camera. To avoid the effects of plasma radiation (x and gamma-rays) and magnetic field variation on the camera, it should be away from the coils. Therefore, the length of the relay lenses determines the total size of the imaging system. The main feature of this imaging system is to realize the variation of field of view (FOV) by interchanging the front-end prime lenses or by using a zoom lens directly rather than designing the optical system afresh, which lowers the cost drastically. The primary purpose of varying FOV is to enrich the versatility of this system, i.e., focusing on a narrow FOV such as gas puff imaging or a wide FOV such as the plasma cross sections. During the HL-2A experiments, this visible imaging system is used to provide high quality pictures of the plasma-wall interaction, divertor detachment, pellet injections, and so on. The frames confirmed that a strong radiation close to the X point is correlated with the completely detached inner target.

[Study on the diagnostic value of transient elastography, APRI and FIB-4 for liver fibrosis in children with non-alcoholic fatty liver disease]

Objective: To evaluate the diagnostic value of transient elastography, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on 4 factors (FIB-4) for liver fibrosis in children with non-alcoholic fatty liver disease (NAFLD). Methods: A retrospective study was conducted on 100 cases of nonalcoholic fatty liver disease in Hunan Children's Hospital between August 2015 to October 2020 to collect liver tissue pathological and clinical data. The receiver operating characteristic curve (ROC curve) was used to analyze the diagnostic value of liver stiffness measurement (LSM), APRI and FIB-4 in the diagnosis of different stages of liver fibrosis caused by NAFLD in children. Results: The area under the ROC curve (AUC) value of LSM, APRI and FIB-4 for diagnosing liver fibrosis (S≥1) were 0.701 [95% confidence interval (CI): 0.579 ~ 0.822, P = 0.011], 0.606 (95%CI: 0.436 ~ 0.775, P = 0.182), and 0.568 (95%CI: 0.397 ~ 0.740, P = 0.387), respectively. The best cut-off values were 6.65 kPa, 21.20, and 0.18, respectively. The AUCs value of LSM, APRI, and FIB-4 for diagnosing significant liver fibrosis (S≥ 2) were 0.660 (95% CI: 0.552 ~ 0.768, P = 0.006), 0.578 (95% CI: 0.464 ~ 0.691, P = 0.182) and 0.541 (95% CI: 0.427 ~ 0.655, P = 0.482), respectively. The best cut-off values were 7.35kpa, 24.78 and 0.22, respectively. The AUCs value of LSM, APRI and FIB-4 for the diagnosis of advanced liver fibrosis (S≥ 3) were 0.639 (95% CI: 0.446 ~ 0.832, P = 0.134), 0.613 (95% CI: 0.447 ~ 0.779, P = 0.223) and 0.587 (95% CI: 0.411 ~ 0.764, P = 0.346), respectively. The best cut-off values were 8.55kpa, 26.66 and 0.27, respectively. Conclusion: The transient elastography technique has a better diagnostic value than APRI and FIB-4 for liver fibrosis in children with NAFLD.

[Effect of lipopolysaccharide-stimulated exosomes from human dental pulp stem cells combined with stromal cell-derived factor-1 on dental pulp regeneration]

Objective: To investigate the effect of exosomes from mild-inflammation- stimulated human dental pulp stem cells (hDPSC) combined with stromal cell-derived factor-1 (SDF-1) on dental pulp regeneration in rats. Methods: Primary hDPSCs were isolated, cultured and then stimulated by using lipopolysaccharide (LPS). The exosomes from the hDPSCs with (L-EXO) or without (N-EXO) LPS were extracted by overspeed differential centrifugation and were identified by transmission electron microscopy and Western blotting. Forty SD rats, aged 6-8 weeks, were equally divided into S group (SDF-1 alone), L+S group (L-EXO combined with SDF-1), N+S group (N-EXO combined with SDF-1) and blank control group (no substance implanted into the root canal) by random number table method. Bilateral mandibular first molars were used as the experimental teeth to establish pulpless root canal models and different contents were implanted into the root canals according to the groups. All rats were over-anesthetized and sacrificed at the 30th day after content implantation. Bilateral mandibular tissues were taken for histological evaluation by means of HE, Masson and immunohistochemical stainings. Results: The HE staining showed new pulp-like tissue in the root canals of all three experimental groups. The amount of new tissues and the number of cells in the tissues were greatest in L+S group and least in S group. Masson staining showed that the mineralized tissue in L+S group was arranged longitudinally along the root canal wall and the collagen fibers were arranged in an orderly fashion, while those in N+S group showed an irregular and disordered distribution. Quantitative analysis of the area of neovascularization in each group showed that the density of vessels in the L+S group [(2.03±0.65)%] was significantly higher than that in the S group [(0.65±0.05)%] and the N+S group [(1.06±0.38)%] respectively (F=5.879, P<0.05). Immunohistochemical staining showed that the expression of CXC chemokine receptor 4 (CXCR4) was significantly lower in S and L+S groups than in N+S group, with a statistically significant difference (F=8.633, P<0.01). Conclusions: Exosomes secreted by hDPSCs combined with SDF-1 might increase the amount of new tissue in the root canal and the density of blood vessels in the tissue. L-EXO showed a stronger effect than N-EXO did. The combination of L-EXO with SDF-1 might result in more regular arrangement of mineralized tissue and collagen fibers in the regenerative tissues.

[Prediction of the vaulting after posterior chamber intraocular lens implantation]

Objective: To investigate the influencing factors on the vaulting one month after implantable collamer lens (ICL) implantation, and to develop and verify a prediction formula. Methods: The first half of this study was retrospective case series study, and the second half was cross-sectional stydy. A total of 83 eyes of 83 patients who underwent ICL implantation in the Lixiang Eye Hospital of Soochow University were included in the first half of the study, with an average age of (27±5) years, from August 1, 2019 to December 30, 2019. All patients underwent a complete preoperative examination, including axis length, anterior chamber depth, comprehensive optometry, intraocular pressure, central corneal thickness, white-to-white diameter, horizontal and vertical sulcus-to-sulcus diameter (STS), crystalline lens thickness (LT), corneal curvature, and bright and dark pupil diameter. Multiple linear regression (stepwise) was used to develop a prediction formula. In the validation part, a total of 65 people (65 eyes) were included, with an average age of (26±5) years, from March 1, 2020 to June 1, 2020. The accuracy and reliability of the formula were verified by the intergroup correlation coefficient and Bland-Altman consistency test. Results: At 1 month after surgery, ICL size had the greatest impact on the vaulting (β=0.942, P<0.001), followed by horizontal STS (β=-0.517, P<0.001), LT (β=-0.376, P<0.001), and vertical STS (β=-0.257, P=0.017). The influence of other factors was not statistically significant (all P>0.05). The regression equation was as follows: the vaulting (μm)=-1 369.05+657.12×ICL size-287.41×horizontal STS-432.50×LT-137.33×vertical STS (the fitting degree R=0.813, R²=0.660, and corrected R²=0.643). In the verification part, the predicted average vaulting was (497.31±102.75) μm, while the actual vaulting was (514.62±152.99) μm. About 96.92% (63/65) of the patients were fitted in the moderate vault, and 3.08% (2/65) were in the high vault. The intergroup correlation coefficient was 0.581. According to the Bland-Altman test, the actual vaulting was 17.31 μm, higher than the predicted value, and the 95% confidence interval of the difference was -260.28 to 294.90 μm. Conclusion: The ICL size, horizontal and vertical STS and LT are the factors that affect and predict the vaulting one month after ICL implantation, and our prediction formula has good accuracy and reliability. (Chin J Ophthalmol, 2021, 57: 519-525).

[Diagnosis and treatment of anastomotic leak after low anterior resection for rectal cancer: current status and future prospect]

Anastomotic leak is one of inevitable postoperative complications of rectal cancer. With the improvement of surgical techniques, the enhancement of the cognization of rectal cancer, and the development of surgical instruments, surgical procedures of rectal cancer are getting more sophisticated. The anastomosis is performed lower and lower, however the incidence of anastomotic leak is not significantly decreased. In addition, different from intraperitoneal anastomotic leak, the low rectal anastomotic leak after low anterior resection has many special issues in the diagnosis and treatment in clinic. The incidence of peritonitis caused by low anastomotic leak is low, the onset time is late, and symptoms of peritonitis are mild. So most low anastomotic leak is treated conservatively, second surgical repair or resection of anastomotic site is rarely performed, and proximal intestinal diversion is commonly performed. In the prevention of low anastomotic leak, some techniques and precautions during the perioperative period and identification of high risk factors might play important roles. Combined our clinical experiences, we introduced the diagnosis, treatment, prevention and research progression of low anastomotic leak after anterior resection of low rectal cancer, we hope it would be helpful.

[Willingness of post-exposure prophylaxis and possible related factors in men who have sex with men]

Objective: To analyze the willingness of post-exposure prophylaxis (PEP) to prevent HIV transmission and related factors in men who have sex with men (MSM). Methods: Cross sectional survey design was used in this study. After informed consent, MSM aged 18 years or above and having had homosexual anal or oral sex in the past 6 months were recruited through "i WeChat" official account between September and November, 2019. Results: Of 1 517 MSM were surveyed, the proportion of MSM who had ever heard of PEP were 72.5% (1 100/1 517) and 87.9%(1 333/1 517) of the MSM said they would like to use PEP if it is needed.Multivariate logistic regression analysis suggested that aged above 25 year (OR=1.807, 95%CI: 1.090-2.995), HIV test history (OR=1.953, 95%CI: 1.171-3.256) and being aware of PEP (OR=2.163, 95%CI: 1.468-3.186) were the positive factors for PEP use, but an aware of the HIV status of sexual partner was the negative factor for PEP (OR=0.602, 95%CI: 0.407-0.890). Among MSM who had ever heard of PEP, the positive factors for PEP use included living in Zhejiang (OR=1.942, 95%CI: 1.097-3.438), aged above 25 years (OR=2.431, 95%CI: 1.331-4.439), being aware of PEP (OR=3.714, 95%CI: 1.532-9.007) obtaining information about PEP service from MSM organization/volunteer/health organization. Conclusions: MSM's willingness to use PEP services was relatively high. Age, awareness of PEP related knowledge, and awareness of sexual partner's HIV infection status were the related factors. MSM organization/volunteer/health organization were the main forces for PEP promotion in MSM.

Investigate clinical characteristics and genetic mutations of CPVT patients in Taiwan and risk stratification

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science and Technology

Background

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare and lethal arrhythmia in children and young adults. RYR2 mutation accounts for 60% of CPVT patients. While many articles about CPVT are published in the Caucasian population, only a few studies are based on Asian ethnicity. A CPVT scorecard proposed using Caucasian patients is proven effective in reducing the burden of variants of uncertain significance (VUS) of RYR2 mutations is not yet tested in the Asian population.

Purpose

Identify mutations among Taiwanese CPVT patients and compare genetic and clinical results with other ethnicities. We also tested the efficacy of the CPVT scorecard in Taiwanese CPVT patients.

Methods

40 clinically diagnosed CPVT patients and their family members were consecutively enrolled from multi-centers. We compared clinical characteristics and genetic results with other ethnicities, and applied the Caucasian CPVT scorecard to test whether it is applicable in Taiwanese CPVT patients.

Results

This is the first nationwide CPVT cohort in Taiwan. Among the 29 patients with CPVT-related gene mutation, 12 RYR2 variants was identified in our cohort with 5 of them unreported in previous studies. The RYR2 yield rate was 55%, similar to other ethnicities. Exercise-induced symptoms including syncope and cardiac arrest were more severe in Taiwanese CPVT cohort, compared to Japanese and Caucasian cohorts. The CPVT scorecard also successfully reduced the VUS rate for the Taiwanese cohort.

Conclusions

Our study demonstrated genetic difference in CPVT patients across ethnicities, suggesting the importance of genetic testing in Taiwan. The CPVT scorecard is applicable to Taiwanese CPVT patients and is a helpful tool in interpreting genetic test results in clinical practice. Clinical characteristics of the cohort Gender (male, %) 15 (52%) Mean age of onset (years) 18 ± 15 Exercise-related syncope or cardiac arrest (n, %) 23 (79%) Exercise-related cardiac arrest (n, %) 14 (48%) Family history of unexplained sudden cardiac death (n, %) 5 (17%) Heart rate (bpm) 73 ± 16 Exercise stress test or Holter positive (n, %) 14 (48%) Ventricular arrhythmia (n, %) 23 (79%) Beta-blockers only (n, %) 10 (35%) Intracardiac defibrillator implantation (n, %) 15 (52%) CPVT score 6 ± 3

[Preliminary practice of multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases]

Objective: To preliminarily establish the multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases, and to explore its feasibility. Methods: In this prospective study a total of 150 children with hematological and oncological diseases visited immunization clinic of Shanghai Children's Medical Center from March 2017 to August 2018 were enrolled in this study. After establishing the multidisciplinary team, designing vaccination plan, staff training, implementation and quality control, a multidisciplinary immunization clinic was set up and the vaccination plan were implemented. The implementation rate of vaccination immunization, the HBsAb level and serum hepatitis B surface antibody (HBsAb) level before and after treatment, the HBsAb level and serum immunoglobulin G antibody (IgG) levels of measles, mumps, rubella (MMR) before and 6 months after immunization, the vaccine-related adverse reactions were assessed prospectively. Chi-square test or Fisher exact test was used to compare the differences of antibody level. Results: A total of 124 cases had been vaccinated as planned, with a coverage rate of 82.7%. Among these cases, the difference of HBsAb positive rate before and after treatment was significant (62.9% (78/124) vs.13.7% (17/124), χ²= 63.489, P<0.01). In 64 cases that completed three doses of hepatitis B immunization, there was a significant difference in HBsAb positive rate before and 6 months after immunization (6.3% (4/64) vs. 98.4% (63/64), P<0.01). In 40 cases that completed MMR immunization, the IgG antibody positive rate for measles (22.5% (9/40) vs. 82.5% (33/40), χ²=31.746,P<0.01), mumps (22.5% (9/40) vs.82.5% (33/40), χ²=28.872,P<0.01), rubella (25.0% (10/40) vs.62.5% (25/40), χ²=11.429, P<0.01) before and 6 months after immunization were significantly different. Of the 421 doses of immunization, 25 (5.9%) doses reported controlled systemic or local adverse event. Conclusions: The immunization of pediatric patients with hematological and oncological diseases is of great importance. The newly-developed multidisciplinary cooperation immunization model for Chinese children with hematological and oncological diseases is feasible, and the immunization protocol is safe and has a certain effect.

[Efficacy and safety of hepatitis B re-vaccination in children after completion of chemotherapy and(or) hematopoietic stem cell transplantation]

Objective: To assess the anti-hepatitis B surface antibody (HBsAb) titers in children after completion of chemotherapy and (or) hematopoietic stem cell transplantation (HSCT), evaluate the efficacy and safety of the current hepatitis B re-vaccination schedule. Methods: A total of 239 children who completed their chemotherapy and (or) HSCT and visited the vaccination clinic of Shanghai Children's Medical Center from March 2017 to July 2019 were enrolled in this study. According to the previous diseases, patients were divided into leukemia group (85 cases), lymphoma group (30 cases), solid tumor group (49 cases) and non-malignant hematological disease group (75 cases). According to the treatment of previous diseases, the patients were divided into chemotherapy group (126 cases), HSCT group (89 cases) and chemotherapy plus HSCT group (24 cases). HBsAb titers were assessed both at the time of diagnosis and after completion of treatment and some children who were HBsAb seronegative were re-vaccinated with 3 doses of hepatitis B vaccine, the vaccine-related adverse reactions were monitored. HBsAb titers were measured again one month after the completion of inoculation. HBsAb titers were defined as negative at levels <10 U/L and positive at ≥ 10 U/L. Chi-square test or Fisher exact test was used to compare the difference of negative conversion rate of hepatitis B antibody between groups, and Logistic regression was used to explore the risk factors of hepatitis B antibody negative conversion. Results: Among 239 patients, there were 143 males and 96 females. At the time of diagnosis, 179 patients (74.9%) were HBsAb seropositive and 60 patients (25.1%) were HBsAb seronegative. After completion of chemotherapy and (or) HSCT, 133 of 179 children with HBsAb seropositive (74.3%) at diagnosis became HBsAb seronegative. Univariate analysis showed significant differences at the negative conversion rates of HBsAb between different disease groups (χ²=10.211，P=0.015), different treatments groups (χ²=14.899，P<0.01) and different HBsAb titers groups before treatment (χ²=32.117，P<0.01). Logistic regression showed that HSCT (chemotherapy group as the reference, odds ratio (OR）=2.999, 95% confidence interval (CI) 1.276-7.050，P=0.012) and HBsAb titers<328.2 U/L before treatment (HBsAb titers≥328.2 U/L group as the reference, OR=6.397， 95% CI3.159-12.954，P<0.01) were risk factors for negative conversion of HBsAb. Among 48 patients whose HBsAb was seronegative after completion of chemotherapy and (or) HSCT and re-vaccinated with hepatitis B vaccine, 47 (97.9%) cases became HBsAb seropositivie. No serious adverse effects or complications were reported among these patients. Conclusions: After completion of chemotherapy and (or) HSCT, most children completely lose their protective humoral immunity against hepatitis B. Hepatitis B re-vaccination schedule can be efficiently and safely applied in those patients.

[The role of large-scale testing platform in the prevention and control of the COVID-19 pandemic: an empirical study based on a novel numerical model]

Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.

Ethnicity and health inequalities: an empirical study based on the 2010 China survey of social change (CSSC) in Western China

BACKGROUND

In China, ethnic minorities often live in frontier areas and have a relatively small population size, and tremendous social transitions have enlarged the gap between eastern and western China, with western China being home to 44 ethnic minority groups. These three disadvantages have health impacts. Examining ethnicity and health inequality in the context of western China is therefore essential.

METHODS

This paper is based on data from the 2010 China Survey of Social Change (CSSC2010), which was conducted in 12 provinces, autonomous regions and province-level municipalities in western China and had a sample size of 10,819. We examined self-rated health and disparities in self-rated health between ethnic minorities and Han Chinese in the context of western China. Self-rated health was coded as poor or good, and ethnicity was coded as ethnic minority or Han Chinese. Ethnic differences in self-rated health was examined by using binary logistic regression. Associations among sociodemographic variables, SES variable, health behaviour variable, health problem variables and self-rated health were also explored.

RESULTS

Fourteen percent of respondents reported their health to be poor. A total of 15.75% of ethnic minorities and 13.43% of Han Chinese respondents reported their health to be poor, indicating a difference in self-rated health between ethnic minorities and Han Chinese. Age, gender, marital status, education, alcohol, and health problems were the main factors that affected differences in self-rated health.

CONCLUSION

In western China, there were obvious ethnic disparities in self-rated health. Elderly ethnic minorities, non-partnered ethnic minorities, ethnic minorities with an educational level lower than middle school, and ethnic minorities with chronic disease had higher odds of poor self-rated health.

Fast charge exchange recombination spectroscopy on HuanLiu-2A tokamak

A Fast Charge eXchange Recombination Spectroscopy (CXRS) diagnostic with eight radial channels has been implemented on a HuanLiu-2A (HL-2A) tokamak with a time resolution of up to 10 kHz monitoring helium II spectra or 1 kHz monitoring carbon VI spectra. The crucial aspects of the fast CXRS are to improve the spectral intensity and the acquisition frequency. The spectral intensity has been greatly enhanced by customized fiber bundles. The main boost in optimizing the acquisition frequency is achieved by binning more pixel rows of the charge coupled device (CCD) representing one radial channel and by reducing the effective image area of the CCD. Consequently, the sawtooth oscillations of ion temperature and rotation velocity are continuously observed for the first time in the HL-2A tokamak.

[Evaluation on the confidence of refusing unprotected sex behavior and related factors among college students in Zhejiang province]

Objective: To understand the confidence-related factors of refusing unprotected sex behavior among college students in Zhejiang province. Methods: Stratified cluster random sampling method was conducted among college students from 13 colleges and universities in Zhejiang province, from October to November, 2018. A total of 3 718 students who self-reported "ever having had sexual contacts" were enrolled. Chi-square test was used to compare the confidence of rejecting unprotected sex under different demographic characteristics, sexual attitude/behaviors and different intervention approaches. Multivariate logistic regression model was used to analyze the related factors. Results: A total of 3 718 college students were involved in this study with average age as (20.17±1.38) years old and 70.5% (2 620/3 718) were male. The proportions of having confidence to refuse unprotected sex behavior were 74.9% (1 963/2 620) of male and 77.9% (896/1 098) of female students, respectively. According to the results from multivariate logistic regression analysis, factors that related to the confidence of refusing unprotected sex behavior in male students would include, did not accept casual sex behavior (compared with accepted students, OR=2.247, 95%CI: 1.828-2.762), did not accept homosexual behavior (compared with accepted students, OR=1.810, 95%CI: 1.302- 2.516), having casual sex behavior in the past one year (compared with having no sex behavior, OR=1.345, 95%CI: 1.051-1.721), aware of the availability of HIV self-test reagents service in college (compared with did not knew, OR=1.381, 95%CI: 1.011-1.887), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.707, 95%CI: 1.374-2.121). In female students, the factors would include: being urban resident (compared with rural residence, OR=1.816, 95%CI: 1.225-2.693), 21 years old or above (compared with 20 years old or below, OR=1.469, 95%CI: 1.075-2.007), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.597, 95%CI: 1.093-2.333), etc. Conclusions: Both male and female college students had higher confidence in refusing unprotected sex behavior. For male students, refusing casual or homosexual contacts, having casual sex in the recent year, knowing HIV self-test reagents service and having had HIV-related risk self-assessment in college as related factors. However, for female students; city residence, 21 years old and above, and having a HIV infection risk self- assessment in college appeared as related factors. Sexual health education should be strengthened to reduce unprotective sex behavior and to promote HIV infection risk self-assessment among the college students.

Mechanical writing of in-plane ferroelectric vortices by tip-force and their coupled chirality

Recent experiments have demonstrated the existence of vortex or flux-closure domains in ferroelectric nanostructures, which are attractive to develop high-density data storage and novel configurable electronic devices. However, it remains challenging to stabilize in-plane vortex or flux-closure domains in ferroelectric film for the absence of a lateral geometry confinement. Based on a 3D phase field model, here we show that stabilization of isolated or interacting in-plane vortices in ferroelectric film can be achieved via applying a mechanical tip-force. The formation of such dipole vortices is caused by a conjoint effect of the tip-force-induced depolarization effect and in-plane strain. The effects of factors like film thickness, misfit strain, tip force and temperature on the vortex formation are systematically revealed and summarized as phase diagrams. The interaction between tip-induced vortices is also investigated. It is found that as the two tips get closer than the critical distance, the two initially isolated vortices become coupled, with identical or opposite chirality, depending on the distance between the two tips. A maximum data storage density of isolated in-plane vortices in ferroelectric thin film is estimated to be ~1 Tb in^-2. Our work thus demonstrates a mechanical strategy to stabilize dipole vortices, and provides a comprehensive insight into the characteristics of ferroelectric film under a mechanical tip force.

[A clinical performance study of modified CT angiography in detecting bronchial artery-pulmonary artery fistula]

Objective: To evaluate the clinical value of modified computed tomography angiography(CTA) in detecting bronchial artery-pulmonary artery fistula(BPF). Methods: Retrospective analysis was performed on 246 patients with hemoptysis admitted to the First Affiliated Hospital of Wenzhou Medical University from July 2017 to December 2018, who underwent modified CTA and DSA examination at the same time. CT was performed with Toshiba Aquilion one 320 row 640-slice spiral CT scanner. All modified CTA images were read blindly by two radiologists above the attending doctors. The sensitivity, specificity and accuracy of the modified CTA in diagnosing BPF were calculated with the DSA results as the reference,and the consistency of the two tests was analyzed. Results: DSA detected 186 cases of positive and 60 cases of negative, modified CTA detected 160 cases of positive and 86 cases of negative. The sensitivity,specificity and accuracy of modified CTA for BPF diagnosis was 85.5%(159/186),98.3%(59/60), 88.6%(218/246) respectively, and they were with high consistency with DSA examination results (kappa=0.73,P<0.01). Conclusion: Modified CTA has high diagnostic specificity for BPF,which can be used as the preferred method for non-invasive screening of suspected BPF patients.

[Analysis on the transmission characteristics of newly reported human immunodeficiency virus/acquired immunodeficiency syndrome cases based on the molecular transmission network in Huzhou, Zhejiang, 2017]

Objective: Using field epidemiological investigation and molecular analysis to construct the molecular transmission network of human immunodeficiency virus/acquired immunodeficiency syndrome cases (HIV/AIDS) newly diagnosed in Huzhou in 2017, Zhejiang Province. Methods: A total of 160 participants were obtained through a web-based system from Chinese Center for Disease Control and Prevention (CCDC) with the features of diagnosed in Huzhou in 2017 who also had been collected samples for the first follow-up. The basic information of demographic characteristics and risk factors was extracted from the website. RNA was extracted from plasma samples of untreated cases, followed by RT-PCR and nest-PCR for pol gene amplification, sequencing. Phylogenetic tree was constructed by MEGA software for HIV gene subtyping. TN93 model was used for calculating the distance between two sequences. Cytoscape software was used for drawing molecular transmission network. And then an epidemiological survey was conducted to cases in the primary cluster. Results: A total of 138 sequenced individuals (86.3%) were acquired from 160 individuals. Among which, 123 (89.1%) were male. The highest proportion of subtype was CRF07_BC (60, 43.5%), followed by CRF01_AE (46, 33.3%), and with four cases of Unique Recombinant Form (URF, CRF01_AE and CRF07_BC) and one case of URF (subtype B and C). A total of 18 molecular clusters included 56 individuals (40.6%) were found in the transmission network under the optimal genetic distance threshold (1.0%). The clustering proportion of CRF07_BC (66.1%, 37 cases) was higher than that of CRF01_AE. There were 9 clusters formed among CRF07_BC, including 37 cases (accounting for 61.7%, 37/60). The primary transmission cluster contained 11 cases, among which 9 cases were transmitted by homosexual sex. The first time of the cases to have homosexual behavior is range from 2010 to 2016, whose media number (P(25), P(75)) of partners was 6 (3.5, 8.5). Most of the cases come from Anhui Province and engaged in garment industry (5 cases), between which there were 8 cases used Blued software to seek for casual partners, 1 case seeking for casual partners in garden. Conclusion: With CRF07_BC and CRF01_AE predominantly circulating, HIV genetic diversity had been noticed in this area. The primary cluster was consisted of high proportion of locally new infections, and a specific population aggregation in limited place existed.

Downregulation of miR-1294 associates with prognosis and tumor progression in epithelial ovarian cancer

OBJECTIVE

Increasing evidence has revealed that microRNAs (miRNAs) act as key players in the regulation of tumor growth and metastasis in epithelial ovarian cancer (EOC). However, the clinical role and functional effects of miR-1294 in EOC remain unknown.

PATIENTS AND METHODS

We examined the expression of miR-1294 in 69 cases of EOC tissues and cell lines by quantitative Real-time polymerase chain reaction (qRT-PCR). The associations of miR-1294 expression with clinicopathologic features and overall survival of EOC patients were analyzed. Biological functional effects of miR-1294 expression on cell growth were analyzed using Cell Counting Kit-8 (CCK8) assays and flow cytometry assays in vitro.

RESULTS

In the present study, we identified that miR-1294 expression was lower in 76 specimens of EOC compared to adjacent normal tissues. Lower miR-1294 expression was related to FIGO stage, lymph node metastasis and shorter overall survival rate in EOC patients. Multivariate Cox analysis demonstrated that miR-1294 expression was an independent prognostic indicator of EOC patients. Gain function assays showed that miR-1294 overexpression inhibited cell proliferation and cell cycle progression in EOC.

CONCLUSIONS

Our results indicated that miR-1294 acted as a prognostic biomarker and potential target of EOC treatment.

P2556TXNDC5 is a novel therapeutic target of atrial fibrosis and fibrillation

Background

Atrial fibrillation (AF), one of the most common cardiac arrhythmias, increases the risk of stroke, systemic embolization and cardiovascular mortality. Atrial fibrosis, a hallmark of chronic AF, provides substrates to initiate/propagate fibrillation waves in the atria. There, however, lacks effective and specific therapeutics targeting atrial fibrosis. We have recently identified an endoplasmic reticulum (ER) protein thioredoxin domain containing 5 (TXNDC5) as a critical mediator of cardiac ventricular fibrosis. We hypothesized that TXNDC5 could also play an important role in the pathogenesis of atrial fibrosis and fibrillation.

Purpose

To determine the role of TXNDC5 in atrial fibrosis and fibrillation.

Methods and results

TXNDC5 transcript and protein levels were both significantly upregulated in the atrial tissue from patients with AF. In addition, TXNDC5 mRNA expression levels were positively correlated with those of transcripts encoding transforming growth factor β1 (TGFβ1) and extracellular matrix (ECM) proteins in human atrial tissue. Knockdown of TXNDC5 in human atrial fibroblasts (hAF) attenuated TGFβ1–induced hAF activation, proliferation and ECM protein upregulation, whereas overexpression of TXNDC5 was sufficient to trigger hAF activation, proliferation and ECM protein production. Further experiments revealed that the fibrogenic effects of TXNDC5 were dependent on c-Jun N-terminal kinase (JNK) signaling. Furthermore, using α-MHC-TGFβcys33ser mice, a transgenic mouse model with cardiac-specific overexpression of constitutively active TGFβ, which develop extensive atrial fibrosis and inducible AF, we showed that TXNDC5 was strongly upregulated in the fibrotic atria of α-MHC-TGFβcys33ser mice and specifically enriched in collagen-secreting atrial fibroblasts. Targeted deletion of TXNDC5 (Txndc5−/−) in α-MHC-TGFβcys33ser mice considerably mitigated the extent of atrial fibrosis. In addition, transesophageal atrial burst pacing induced AF in 75% (3 out of 4) α-MHC-TGFβcys33ser mice, whereas knockout of Txndc5 markedly reduced the inducibility of AF (25%, 3 out of 12) in α-MHC-TGFβcys33ser mice (Figure).

TXNDC5 KO Reduces AF Inducibility

Conclusion

The present study revealed that ER protein TXNDC5 augments atrial fibrosis by promoting cardiac fibroblast proliferation and ECM protein production via JNK signaling activation. Targeted deletion of Txndc5 protects against TGFβ induced atrial fibrosis and AF. Targeting TXNDC5, therefore, could be a promising new therapeutic approach to treat or prevent atrial fibrosis and AF.

[Status and associatied factors of anal sexual intention in casual sex behavior among heterosexual college students in Zhejiang Province]

Objective: To identify the status and risky factors of anal sexual intention in casual sex behavior in Zhejiang province. Methods: Stratified cluster sampling was conducted among college students in 13 colleges in 11 cities between October to November, 2018. 482 students were enrolled who self-reported "heterosexuality "and" ever had casual sex behavior". A self-designed network questionnaire was complimented containing basic information, knowledge of HIV, sexual behavior. Chi-square test was used to compared the difference of anal sex intention between different characteristic. The multivariate logistic regression methods was used to analyze the influence factors. Results: Among 482 students, the age was (20±1.442) years old. And 87.3% (421) were male and 29.0% (140) were from other province. The rate of anal sex intention were 19.4% (94/482) in total, with the rates of 38.1% (24/63) and 14.4% (53/367) in students with sexual number more than 5 and less than 5 (P<0.001), separately. Compared with students searching casual sexual partner with non-internet access (17.0%, 16/201), students searching sexual partner with internet access had higher risk of anal sex practice (27.8%, 78/281) (P<0.001). The rate of anal sex practice among students reporting "ever had casual sex after drinking "and" never had casual sex after drinking" were 30.5% (64/210) and 9.4% (25/266) (P<0.001). The multivariate logistic regression results revealed that compared with students searching casual sexual partner with non-internet access and reporting "never had casual sex after drinking", subjects searching sexual partner with internet access(OR (95%CI)=2.65 (1.34-5.23)) and "ever had casual sex after drinking" OR (95%CI)=3.02 (1.65-5.33) were more likely had higher risk of anal sex practice. Conclusion: Heterosexual college students in Zhejiang Province tend to have anal intercourse with causal sexual partners. Searching for causal sexual partners on internet or mobile phone dating software and having temporary sexual behavior after drinking were correlated factors.

[Epidemiological characteristics of molecular transmission cluster among reported HIV/AIDS cases in Jiaxing city, Zhejiang province, 2017]

Objective: To understand the epidemiological characteristics of one large HIV molecular transmission cluster in Jiaxing city, Zhejiang province, 2017 in order to select those people under high-risk and providing basis for programs on prevention. Methods: During 2017, newly diagnosed HIV/AIDS cases in this city were recruited. Plasma samples were collected from subjects, followed by RNA extraction, RT-PCR and nest-PCR for pol gene amplification, before being sequenced and aligned. Mega 6.0 software was used to construct phylogenetic tree, and Cytoscape 3.6.0 software was used to identify HIV molecular transmission clusters. Cases within the large transmission clusters were investigated, using a field-epidemiology-questionnaire. Data related to socio-demographics and previous sexual behaviors were collected and EpiData 3.0 and SPSS 20.0 software were used. Results: In the large transmission cluster with subtype identified as CRF07_BC, in Jiaxing, 2017, 26 cases of the total 30 cases were investigated. A total of 80.8% (21/26) could be identified as newly infected within the last two years and 30.8%(8/26) could be identified as newly infected within the last one year, including 22 cases infected locally. Among several infected cases who were at age 45 years or older, they admitted that they had experienced unprotected sexual contacts in local city for long time and having had more than 10 disclosed sexual contacts within the last two years at the local venues. Conclusions: This molecular cluster had been formed and scaled up quickly in recent two years, it has played an important role in promoting and scaling up the HIV transmission. Three cases identificed as high risk played an importantrde role in scaling up this cluster.

On the mechanisms of tip-force induced switching in ferroelectric thin films: the crossover of depolarization, shear strain and flexoelectricity

The recent observation of mechanical switching of ferroelectric polarization has placed the mechanical manipulation of ferroelectrics on an equal footing with the conventional electrical manipulation. However, discussions on the exact switching mechanisms due to mechanical loads are ongoing for the complexity in experimental situations. In this work, based on continuum mechanical and thermodynamic modeling and simulation, we analyze the mechanisms of tip-force induced switching in ferroelectric thin films. The roles of depolarization, shear strain and flexoelectricity in mechanical switching, both in normal and sliding loading modes, are separated out and the switching characteristics are analyzed. The depolarization field in the film is demonstrated to enable bidirectional switching. The coupling between shear strain and polarization components is shown to be important in the sliding loading mode. A great influence of flexoelectricity-modified polarization boundary condition on the switching process is revealed. The previous speculation that the switching process experiences an intermediate paraelectric phase is proved. The regulation of loading force, misfit strain, temperature and film thickness on the switching are further given for each mechanism. Taking all of the three mechanisms into account, we present the phase diagrams of mechanical switching for films in an initial upward or downward polarization state. The revealed characteristics of various switching mechanisms should provide useful guidelines for their verification in experiments, and the tunability of the switching by various influencing factors is instructive for the design and optimization of ferroelectric devices via mechanical engineering.

[All levels miniplate fixation and a modified hybrid fixation method in expansive open-door cervical laminoplasty: a retrospective comparative study]

OBJECTIVE

To retrospectively compare the effect of alternate levels miniplate and anchor fixation with the effect of all levels miniplate fixation in expansive open-door cervical laminoplasty (EOLP).

METHODS

Patients with cervical spondylosis underwent EOLP between July 2015 and June 2016 were included in the study. There were 33 patients in the alternate group (alternate levels miniplate and anchor fixation group) and 34 patients in the miniplate group (all levels miniplate fixation group). Neurological function was evaluated with the Japanese Orthopedic Association (JOA) score and degree of pain was assessed with the visual analogue scale (VAS) score. Basic clinical and surgical data, complication rates and medical costs of the two groups were compared. In addition, radiological examinations were performed pre- and post-operatively and at the final follow-up. Relative imaging data such as anteroposterior diameter (APD), cervical curvature index (CCI) and open angle were collected and compared.

RESULTS

(1) The mean follow-up time was 18.6 months in the alternate group and 18.9 months in the miniplate group. There were no significant differences in operation time, intraoperative blood loss, perioperative complication rates, post-operative hospital stays, VAS scores and neurological recovery rates preoperatively and at the final follow-up between the two groups. (2) Additionally, no obvious differences were observed about CCIs and APDs at the three follow-up time points between the two groups. Post-operative open angles at C4 and C6 in the alternate group were significantly smaller than those in the miniplate group. However, there were no significant differences in C3, C5 and C7 open angles between the two groups post-operatively. Notably, no significant differences were detected about the open angles at all levels between the two groups at the final follow-up. (3) When comparing radiologic data at different time points in each group, CCIs and open angles at each level had no significant differences, but APDs after surgery and at the final follow-up were significantly larger than pre-operative APDs. (4) Total costs in the alternate group were significantly lower than those in the miniplate group.

CONCLUSION

The two surgical methods showed almost the same neurological recovery rates and complication rates. However, use of alternate levels miniplate and anchor fixation in EOLP can reduce medical expenses.

Note: Real-time wavelength matching system designed for the motional Stark effect polarimeter on HL-2A tokamak

A 7-channel motional Stark effect diagnostic based on dual photo-elastic modulators is installed and operated routinely for rather low beam energy and magnetic field on the HL-2A tokamak, with a spatial resolution of ∼3 cm and a temporal resolution of 10 ms. The instrument observes the σ component of the full energy D_α from the first or the fourth ion source of a neutral beam injector. However, the change in beam energy during a discharge causes variation of the Doppler shift with the maximum of 1 Å, which leads to the polarization fraction drop from 30%-40% to 10% and then makes the signal-to-noise ratio of the system become very poor. Therefore, a real-time wavelength matching system is designed to promote polarization fraction. The beam emission spectra are filtered by using a monochrometer in real time. And a narrowband filter is tilted by using an absolutely calibrated rotator through beam energy in order to make sure that the deviation of wavelength matching is less than 0.1 Å.

[Electrophysiological and pathological features of peripheral nerve in rats exposed to 1-bromopropane]

Objective: To study the electrophysiological changes and pathological characteristics of peripheral nerve in rats exposed to 1-bromopropane through chronic inhalation. Methods: 40 male SD rats were randomed divided into 4 groups, and exposed to 1-bromopropane vapor at concentrations of 1 000 mg/m(3), 2 000 mg/m(3), 4 000 mg/m(3) and fresh air respectively, 6 hours per day, 5 days per week for 12 weeks. The changes of nerve conduction velocity (NCV) , electromyography (EMG) and pathology were observed. Results: After 4 weeks of exposure, the body weights of high dose group are lower than that of the control group. Compared with the control group, the high and medium dose group have a decline in MCV and CMAPs, while SCV and SNAPs descend in the high dose group (P<0.05) . The EMG examination showed that there are denervation changes in high dose group. Sciatic nerve biopsy observed by electron microscope showed that axonal degeneration and demyelination coexist in the rats exposed to high concentration. Conclusion: Chronic inhalation of 1-bromopropane at the concentration of 4 000 mg/m(3) can cause peripheral nerve injury, which is characterized by axonal degeneration and demyelination. Axonal degeneration is the main pathological change.

[Effect of nerve growth factor on chronic peripheral neuropathy in rats induced by 1-bromopropane]

Objective: To observe the effect of nerve growth factor (NGF) and Mecobalamin on chronic peripheral neuropathy in rats induced by 1-bromopropane. Methods: 36 male SD rats were exposed to 1-bromopropane vapor at concentrations of 4 000 mg/m(3), 6 hours per day, 5 days per week for 12 weeks. The rats were randomed divided into 4 groups, and treated by Mecobalamin for 300 μg/kg qd, NGF for 40 μg/kg qd, Mecobalamin+NGF with the dose as mentioned above, respecively. The control group were fed in normal condition. The changes of Sciatic nerve conduction velocity (NCV) , electromyography (EMG) and pathology were observed 30 days later. Results: The nerve conduction velocity were decreased in all the rats. Compared with the control group, the motor nerve conduction velocity (MCV) was improved in group Mecobalamin and group Mecobalamin+NGF, The difference was statistically significant, as the sensory nerve conduction velocity (SCV) was improved only in group Mecobalamin+NGF. Sciatic nerve biopsy observed by electron microscope showed that myelinated nerve fibers were obvious swelling, lamellar separation, partial myelin vacuolization, and axonal degeneration. After treatment with exogenous nerve growth factor, the number and severity of damaged nerve fibers were restored. Conclusion: Exogenous nerve growth factor contributes to the recovery of peripheral nerve damage induced by 1-bromopropane.

[Retrospective analysis of cuffed-tunneled catheters in pediatric patients receiving maintenance hemodialysis]

Objective: To summarize the characteristics of cuffed-tunneled catheters insertion and investigate the values of cuffed-tunneled catheters in pediatric patients. Methods: Between March 2015 and July 2017, all the pediatric patients who received maintenance hemodialysis at least 3 consecutive months in our center were included. Sixteen cuffed-tunneled hemodialysis catheters were inserted in patients for long-term hemodialysis access. The clinical manifestations and complications were retrospectively reviewed. Results: Fifteen pediatric patients with end stage ranal disease (ESRD) were included in this study and they received 16 cuffed-tunneled catheters for long-term vascular access, including 10 males and 5 females; median age at start of catheter insertion was 11.5 (4.2-14.5) years. Body weight was (27.8±8.0)kg (16.0-39.4 kg) . The size and the length of the catheters were based on the height of patients as follows: 28 cm for (115.6±10.6) cm (102.0-130.0 cm) ,36 cm for (148.6±9.9)cm (140.0-167.0 cm) . Cuffed-tunneled catheters outcome: 10 cuffed-tunneled catheters were still functional at the end of the study; 5 catheters were removed after successful kidney transplantation. Catheter failure occurred in 1 out of 16 cuffed-tunneled catheters due to catheter-related infections. The median catheter survival time was 11.9 months (range 3.5-21.3 months). Complications of cuffed-tunneled catheters: Catheter placements operation was successful in 15 cases using ultrasound guidance. No serious complications were observed in any patients receiving catheter inserting operation. The overall rate of catheter-related infections and thrombosis/malposition was 6.3% and 18.7%, respectively. Conclusions: Ultrasound guidance is suggested in pediatric patients during the catheters insertion. The size and the length of the catheters should be based on the height of patients. Cuffed-tunneled hemodialysis catheters could be effectively used for maintenance of hemodialysis vascular access for pediatric patients with ESRD.

[Technical specification for clinical application of critical ultrasonography]

Critical ultrasonography(CUS) is different from the traditional diagnostic ultrasound, the examiner and interpreter of the image are critical care medicine physicians. The core content of CUS is to evaluate the pathophysiological changes of organs and systems and etiology changes. With the idea of critical care medicine as the soul, it can integrate the above information and clinical information, bedside real-time diagnosis and titration treatment, and evaluate the therapeutic effect so as to improve the outcome. CUS is a traditional technique which is applied as a new application method. The consensus of experts on critical ultrasonography in China released in 2016 put forward consensus suggestions on the concept, implementation and application of CUS. It should be further emphasized that the accurate and objective assessment and implementation of CUS requires the standardization of ultrasound image acquisition and the need to establish a CUS procedure. At the same time, the standardized training for CUS accepted by critical care medicine physicians requires the application of technical specifications, and the establishment of technical specifications is the basis for the quality control and continuous improvement of CUS. Chinese Critical Ultrasound Study Group and Critical Hemodynamic Therapy Collabration Group, based on the rich experience of clinical practice in critical care and research, combined with the essence of CUS, to learn the traditional ultrasonic essence, established the clinical application technical specifications of CUS, including in five parts: basic view and relevant indicators to obtain in CUS; basic norms for viscera organ assessment and special assessment; standardized processes and systematic inspection programs; examples of CUS applications; CUS training and the application of qualification certification. The establishment of applied technology standard is helpful for standardized training and clinical correct implementation. It is helpful for clinical evaluation and correct guidance treatment, and is also helpful for quality control and continuous improvement of CUS application.

Morphology-controlled epitaxial vanadium dioxide low-dimensional structures: the delicate effects on the phase transition behaviors

As an important strongly correlated electron material, VO2 undergoes a metal-insulator transition (MIT) accompanied by a huge change of several orders of magnitude in conductance and transmittance. The MIT behavior can be controlled by low-dimensional structures (LDSs) and the interaction between LDSs and substrates. Consequently, fabricating the LDSs and understanding the phase transition behaviors have great significance for the investigation of fundamental properties and applications. Using the pulsed laser deposition technique, we fabricate abundant LDSs (i.e., from zero-dimensional nanodots, one-dimensional nanowires, nanobelts and nanorods to two-dimensional nanoplatelets and ultra-thin films, and zero-/one-/two-dimensional mixed structures), and investigate the controllability of each deposition factor on the growth of the LDSs. TEM results confirm the high crystallinity of the as-synthesized LDSs. AFM results and ab initio calculations demonstrate the great influence of substrates on the growth orientation of the LDSs. More importantly, we systematically investigate the phase transition characteristics of the LDSs by temperature-dependent Raman spectroscopy and XRD. The results clearly reveal the structural dependence of the phase transition features due to the delicate effects of substrates and structures. Our technique provides a rapid, controllable and easy method for fabricating VO2 LDSs, which can lead to a deeper understanding of the electrical, optical, and magnetic properties and potential applications of VO2.

[Molecular epidemiology and transmission of HIV-1 infection in Zhejiang province, 2015]

Objective: To understand the distribution of HIV-1 subtype diversity and its transmission characteristics in Zhejiang province. Methods: A total of 302 newly diagnosed HIV-1 positive patients were selected through stratified random sampling in Zhejiang in 2015. HIV-1 pol genes were sequenced successfully with reverse transcription PCR/nested PCR and phylogenetic analysis was conducted for 276 patients. Then a molecular epidemiologic study was performed combined with field epidemiological investigation. Results: Of 276 sequence samples analyzed, 122 CRF07_BC strains (44.2%), 103 CRF01_AE strains (37.3%), 17 CRF08_BC strains (6.1%), 9 B strains (3.2%), 6 CRF55_01B strains (2.2%), 5 C strains (1.8%), 1 CRF59_01B strain (0.4%), 1 CRF67_01B strain (0.4%), 1 A1 strain (0.4%), and 11 URFs strains (4.0%) were identified. Phylogenetic analysis revealed 16 clusters with only 15.1% (34/225) sequences involved among CRF07_BC and CRF01_AE strains. The clustered cases in MSM were higher than that in populations with other transmission routes. And clusters existed between the populations with different transmission routes. Conclusion: The major strains of HIV-1 in Zhejiang are CRF07_BC and CRF01_AE. The HIV subtypes showed more complexity in Zhejiang. It is necessary to strengthen the surveillance for HIV subtypes, carry out classified management and conduct effective prevention and control in the population at high risk.

[Analysis on HIV-1 subtypes and transmission clusters in newly reported HIV/AIDS cases in Yiwu, Zhejiang Province, 2016]

Objective: To understand the characteristics of distribution on HIV-1 subtypes and the transmission clusters in Yiwu in Zhejiang province. Methods: A cross-sectional study of molecular epidemiology was carried out on newly reported HIV/AIDS cases in Yiwu. RNA was extracted from 168 plasma samples, followed by RT-PCR and nest-PCR for pol gene amplification, sequencing, phylogenetic tree construction used for analyzing the subtypes and transmission clusters. Mutations on drug resistance was analyzed by CPR 6.0 online tool. Results: Subjects were mainly males (86.3%, 145/168), with average age as (39.1±13.4) years old and most of them were migrants (66.7%, 112/168). The major routes of transmission included homosexual (51.2%, 86/168) and heterosexual (48.8%, 82/168) contacts. The rate of success for sequence acquisition was 89.9% (151/168). The dominant subtypes showed as CRF01_AE (74, 49.0%) and CRF07_BC (64, 42.4%), followed by CRF08_BC (5, 3.3%), CRF55_01B (3, 2.0%), each case of subtype B, CRF45_cpx, CRF59_01B, CRF85_BC and URF (B/C). CRF45_cpx and CRF85_BC were discovered the first time in Zhejiang province. Twenty-six transmission clusters involving 65 cases were found, with the total clustered rate as 43.0% (65/151), in which the CRF01_AE clustered rate appeared as 54.1% (40/74), higher than that of CRF07_BC (21/64, 32.8%). The average size of cluster was 2.5 cases/cluster, with average size of cluster in CRF01_AE patients infected through heterosexual transmission as the largest (3.5 cases/cluster). The prevalence of transmitted drug resistance was 4.6% (7/151). Seven cases with surveillance drug resistant mutations (SDRM) were found, including 5 cases of M46L (3.3%), and one case of F77L or Y181C. Conclusion: HIV genetic diversity and a variety of transmission clusters had been noticed in this study area (Yiwu). Programs on monitoring the subtypes and transmission clusters should be continued and strengthened.

Mechanical switching in ferroelectrics by shear stress and its implications on charged domain wall generation and vortex memory devices

Combining thermodynamic calculation and phase-field simulation, we revealed that mechanical switching of polarization can be achieved in ferroelectric by shear stressviaa simple mechanism where the presence of flexoelectricity is not necessary.

[CT perfusion analysis on the association of permeability surface with hematoma and edema volume in acute spontaneous putaminal and thalamic hematoma]

Objective: To discuss the correlation of permeability surface (PS) with hematoma and edema volume in acute spontaneous putaminal and thalamic hematoma using CT perfusion imaging. Methods: A total of 48 acute spontaneous putaminal and thalamic hemorrhage patients were enrolled in this study during October 2015 and December 2016 at the First Affiliated Hospital of Wenzhou Medical University. At the image slice with maximum size of hematoma, PS was measured by drawing various regions of interest (ROI) including"hot spots", perihematomal regions, outward regions, hemisphere regions and contralateral mirror regions. The relative PS (rPS) was calculated as the ratio of ipsilateral to contralateral PS value in each ROI. Hematoma and edema volumes were traced and obtained with commercial software. Results: The"hot spots"PS ((2.8±1.5) ml·100 g(-1)·min(-1)) and perihematomal PS ((2.1±1.4) ml·100 g(-1)·min(-1)) were both significantly higher than the PS of the contralateral mirror regions ((1.1±0.5) ml·100 g(-1)·min(-1)) (P<0.001). There was no significant difference in outward regions PS and contralateral mirror regions PS (P>0.05), nor in hemisphere regions PS and contralateral mirror regions PS (P>0.05). There was no significant difference in"hot spots"rPS and perihematomal rPS (P=0.218). The"hot spots"rPS and Perihematomal rPS were both higher than the rPS of the outward and hemisphere regions (P<0.01). There was no significant difference in the outward and hemisphere regions (P<0.01). The median hematoma volume was 12.63 ml and the median edema volume was 12.36 ml. The edema volume had a positive association with the hematoma volume(r=0.799, P<0.001) and perihematomal PS(r=0.465, P=0.001). Perihematomal PS had a positive association with the hematoma volume (r=0.386, P=0.007). Conclusion: The damage of blood-brain barrier around acute spontaneous hematoma can be measured via CT perfusion imaging. Perihematomal PS was associated with the hematoma and edema volume.

Polygenic risk for schizophrenia and neurocognitive performance in patients with schizophrenia

Both neurocognitive deficits and schizophrenia are highly heritable. Genetic overlap between neurocognitive deficits and schizophrenia has been observed in both the general population and in the clinical samples. This study aimed to examine if the polygenic architecture of susceptibility to schizophrenia modified neurocognitive performance in schizophrenia patients. Schizophrenia polygenic risk scores (PRSs) were first derived from the Psychiatric Genomics Consortium (PGC) on schizophrenia, and then the scores were calculated in our independent sample of 1130 schizophrenia trios, who had PsychChip data and were part of the Schizophrenia Families from Taiwan project. Pseudocontrols generated from the nontransmitted parental alleles of the parents in these trios were compared with alleles in schizophrenia patients in assessing the replicability of PGC-derived susceptibility variants. Schizophrenia PRS at the P-value threshold (PT) of 0.1 explained 0.2% in the variance of disease status in this Han-Taiwanese samples, and the score itself had a P-value 0.05 for the association test with the disorder. Each patient underwent neurocognitive evaluation on sustained attention using the continuous performance test and executive function using the Wisconsin Card Sorting Test. We applied a structural equation model to construct the neurocognitive latent variable estimated from multiple measured indices in these 2 tests, and then tested the association between the PRS and the neurocognitive latent variable. Higher schizophrenia PRS generated at the PT of 0.1 was significantly associated with poorer neurocognitive performance with explained variance 0.5%. Our findings indicated that schizophrenia susceptibility variants modify the neurocognitive performance in schizophrenia patients.

Diverse polarization bi-stability in ferroelectric tunnel junctions due to the effects of the electrode and strain: an ab initio study

Both electrodes and substrates are factors of great significance for the performance of ferroelectric tunnel junctions (FTJs) in designing functional nanodevices. To provide a comprehensive view on the polarization stability in FTJs due to the effects of an electrode and a substrate misfit strain, in this work we calculated more than 1000 FTJ structures by utilizing an ab initio density functional theory (DFT) method, via changing the symmetry of the FTJ structure (i.e., both asymmetric and symmetric FTJs), electrodes (including Au, Ag, Cu, Pt, Co, Fe, and SrRuO₃), barrier thickness (ranging from 2 to 10 unit cells), polarization direction (both positive and negative polarizations) and epitaxial strain (i.e., -3%, -2.5%, -2%, -1.5% and -1%) as variables. This shows that the FTJs can exhibit quite diverse polarization bi-stability due to the combined effect of the electrode and strain control, which indicates diverse performance of the FTJs modulated by the electrode and strain. In particular, the polarization-mediated electrostatic potential in the barriers with different electrodes forecasts an electrode-tailored tunnel electroresistance effect. Our study provides guidance on the practical applications of FTJs with regard to the selection of electrodes and substrates.

Characteristics and controllability of vortices in ferromagnetics, ferroelectrics, and multiferroics

Topological defects in condensed matter are attracting e significant attention due to their important role in phase transition and their fascinating characteristics. Among the various types of matter, ferroics which possess a switchable physical characteristic and form domain structure are ideal systems to form topological defects. In particular, a special class of topological defects-vortices-have been found to commonly exist in ferroics. They often manifest themselves as singular regions where domains merge in large systems, or stabilize as novel order states instead of forming domain structures in small enough systems. Understanding the characteristics and controllability of vortices in ferroics can provide us with deeper insight into the phase transition of condensed matter and also exciting opportunities in designing novel functional devices such as nano-memories, sensors, and transducers based on topological defects. In this review, we summarize the recent experimental and theoretical progress in ferroic vortices, with emphasis on those spin/dipole vortices formed in nanoscale ferromagnetics and ferroelectrics, and those structural domain vortices formed in multiferroic hexagonal manganites. We begin with an overview of this field. The fundamental concepts of ferroic vortices, followed by the theoretical simulation and experimental methods to explore ferroic vortices, are then introduced. The various characteristics of vortices (e.g. formation mechanisms, static/dynamic features, and electronic properties) and their controllability (e.g. by size, geometry, external thermal, electrical, magnetic, or mechanical fields) in ferromagnetics, ferroelectrics, and multiferroics are discussed in detail in individual sections. Finally, we conclude this review with an outlook on this rapidly developing field.

Astragalus polysaccharides improve cardiomyopathy in STZ-induced diabetic mice and heterozygous (SOD2+/-) knockout mice

Oxidative stress plays an important role in the development of diabetic cardiomyopathy. In the present study, we determined whether the effect of astragalus polysaccharides (APS) on diabetic cardiomyopathy was associated with its impact on oxidative stress. Streptozotocin (STZ)-induced diabetic mice and heterozygous superoxide dismutase (SOD2+/-) knockout mice were administered APS. The hemodynamics, cardiac ultrastructure, and the apoptosis, necrosis and proliferation of cardiomyocytes were assessed to evaluate the effect of APS on diabetic and oxidative cardiomyopathy. Furthermore, H₂O₂ formation, oxidative stress/damage, and SOD activity in cardiomyocytes were evaluated to determine the effects of APS on cardiac oxidative stress. APS therapy improved hemodynamics and myocardial ultrastructure with reduced apoptosis/necrosis, and enhanced proliferation in cardiomyocytes from both STZ-induced diabetic mice and heterozygous SOD2+/- knockout mice. In addition, APS therapy reduced H₂O₂ formation and oxidative stress/damage, and enhanced SOD activity in both groups of mice. Our findings suggest that APS had benefits in diabetic cardiomyopathy, which may be partly associated with its impact on cardiac oxidative stress.

[Dynamic detection of surface blood flow in rat heart and its application in real time identification of myocardial infarction model]

Objective: To establish a method for monitoring the surface blood flow in the heart of rats, and to clarify the relationship between the degree of myocardial infarction and the blood perfusion on the surface of the heart, so as to provide a new indicator for the identification of rat myocardial infarction model. Methods: The rats were divided into control group (n=23) and model group (n=107), the rat hearts were scanned by the laser doppler perfusion imager before and after operation respectively, and the data was analyzed to acquire the rate of surface blood flow change of the heart. Myocardial infarction size of model group was detected by NBT. Model group were divided into three subgroups of mild myocardial infarction, moderate myocardial infarction and severe myocardial infarction according to the myocardial infarction size, and an analysis was made on the correlativity between rate of surface blood flow change of the heart and myocardial infarction size. Results: Myocardial infarction size was highly correlated to the rate of surface blood flow change of the heart in model group (r=0.849 6, P<0.000 1). There was no significant correlation between infarction size and heart blood flow in the mild myocardial infarction subgroup (r=-0.133 6, P>0.05), while the correlation in moderate myocardial infarction was significant (r=0.721 7, P<0.000 1), and the highest correlation was shown in severe myocardial infarction subgroup (r=0.910 2, P<0.000 1). Conclusion: The heart surface blood flow has a close relationship with the myocardial infarction size in rat, so the change of heart blood perfusion can beused as an effective reference to establish and identify rat myocardial infarction model.

[Analysis of CT perfusion imaging in chronic cerebral circulatory insufficiency and its relationship with crossed cerebellar diaschisis]

Objective: To investigate the change of cerebral microcirculation of chronic cerebral circulation insufficiency(CCCI) patients and the relationship between CCCI and crossed cerebellar diaschisis(CCD)by using 320-detector row of low-dose volume CT perfusion imaging. Methods: A total of 158 patients (103 males, 55 females, from 45 to 82 years old, the mean age was 62.9) with symptoms of CCCI were admitted to the First Affiliated Hospital of Wenzhou Medical University from June 2013 to January 2016. Low-dose CTP imaging of whole brain was performed to them using 320-detector row volume CT scanner. The perfusion parameters such as cerebral blood flow(CBF), cerebral blood volume(CBV), mean transit time(MTT), time to peak(TTP) and DLY in both cerebral blood supply areas and cerebellum were got, so were the 4-dimensional CTA images, and rCBF, rCBV, rMTT and rTTP were calculated by ipsilateral/contralateral value. Comparative t-test and independent t-test were applied to analyzing these parameters quantitatively.Chi-square test and Logistic regression model were applied to analyzing the related clinical risk factors. Results: (1) All 108 patients in CCCI group showed asymmetric perfusion within two cerebral hemispheres in CTP images. The CBF, CBV of diseased side were lower than the contralateral mirror area (t(CBF)=-12.89, t(CBV)=-7.031, P(CBF, CBV)<0.001); the MTT of the diseased side was shorter than the contralateral mirror area (t(MTT) =13.310, P(MTT)<0.001); the TTP of the diseased side was longer than the contralateral mirror area (t(TTP)=-4.012, P(TTP)<0.001). The rCBF and rCBV of CCCI group were lower than that in non-CCCI group (t(rCBF)=3.079, t(rCBV)=2.760, P(rCBF, rCBV)<0.01), while the rTTP of CCCI group was longer than that in non-CCCI group (t(rTTP)=4.846, P(rTTP)<0.001). (2)The results of Chi-square test showed that the differences of gender (χ(2)=4.036, P=0.045), hyperlipidemia (χ(2)=7.687, P=0.006), as well as smoking (χ(2)=11.868, P=0.001) had statistical significance between CCCI group and non-CCCI group.Multi-factor Logistic regression analysis showed that hyperlipidemia (OR value=3.736, P=0.016) and smoking (OR value=4.641, P=0.01) were the risk factors of CCCI, while gender had no relationship with it.(3)The incidence of CCD was 18.5% in the CCCI group, and at the same time, the supratentorial corresponding blood supply areas were classified.A total of 10(34.5%) cases were in blood supply area of posterior cerebral artery, 6(20.7%) cases were in blood supply area of middle cerebral artery, 12(41.4%) cases were of anterior cerebral artery, while only 1(3.5%) case was of basal ganglia, in which 4 cases were in blood supply area of posterior cerebral artery, another 4 cases were middle cerebral artery, 7 cases were of anterior cerebral artery and no case of basal ganglia respectively leading CCD alone. Conclusions: CTP could display the microcirculation situation of abnormal brain tissue perfusion area intuitively and quantitatively. Additionally, it could reflect the degree of relationship between cerebral several blood supply areas and cerebellum.