An atypical two-component system, AtcR/AtcK, simultaneously regulates the biosynthesis of multiple secondary metabolites in Streptomyces bingchenggensis

Streptomyces bingchenggensis is an industrial producer of milbemycins, which are important anthelmintic and insecticidal agents. Two-component systems (TCSs), which are typically situated in the same operon and are composed of a histidine kinase and a response regulator, are the predominant signal transduction pathways involved in the regulation of secondary metabolism in Streptomyces. Here, an atypical TCS, AtcR/AtcK, in which the encoding genes (sbi_06838/sbi_06839) are organized in a head-to-head pair, was demonstrated to be indispensable for the biosynthesis of multiple secondary metabolites in S. bingchenggensis. With the null TCS mutants, the production of milbemycin and yellow compound was abolished but nanchangmycin was overproduced. Transcriptional analysis and electrophoretic mobility shift assays showed that AtcR regulated the biosynthesis of these three secondary metabolites by a MilR3-mediated cascade. First, AtcR was activated by phosphorylation from signal-triggered AtcK. Second, the activated AtcR promoted the transcription of milR3. Third, MilR3 specifically activated the transcription of downstream genes from milbemycin and yellow compound biosynthetic gene clusters (BGCs) and nanR4 from the nanchangmycin BGC. Finally, because NanR4 is a specific repressor in the nanchangmycin BGC, activation of MilR3 downstream genes led to the production of yellow compound and milbemycin but inhibited nanchangmycin production. By rewiring the regulatory cascade, two strains were obtained, the yield of nanchangmycin was improved by 45-fold to 6.08 g/L and the production of milbemycin was increased twofold to 1.34 g/L. This work has broadened our knowledge on atypical TCSs and provided practical strategies to engineer strains for the production of secondary metabolites in Streptomyces.IMPORTANCEStreptomyces bingchenggensis is an important industrial strain that produces milbemycins. Two-component systems (TCSs), which consist of a histidine kinase and a response regulator, are the predominant signal transduction pathways involved in the regulation of secondary metabolism in Streptomyces. Coupled encoding genes of TCSs are typically situated in the same operon. Here, TCSs with encoding genes situated in separate head-to-head neighbor operons were labeled atypical TCSs. It was found that the atypical TCS AtcR/AtcK played an indispensable role in the biosynthesis of milbemycin, yellow compound, and nanchangmycin in S. bingchenggensis. This atypical TCS regulated the biosynthesis of specialized metabolites in a cascade mediated via a cluster-situated regulator, MilR3. Through rewiring the regulatory pathways, strains were successfully engineered to overproduce milbemycin and nanchangmycin. To the best of our knowledge, this is the first report on atypical TCS, in which the encoding genes of RR and HK were situated in separate head-to-head neighbor operons, involved in secondary metabolism. In addition, data mining showed that atypical TCSs were widely distributed in actinobacteria.

[Annual review of progress in research on chronic obstructive pulmonary disease(2022-2023)]

Chronic obstructive pulmonary disease (COPD) is the most common chronic airway disease, with a high prevalence and high disease burden. Clinical questions have driven advances in clinical research that continue to deepen our understanding of COPD. At the same time, new perspectives, evidence, and strategies have emerged. Studies since 2022 have increased knowledge of the impact of risk factors, such as low-to-moderate income and ambient ozone, on the prevalence of COPD. The effect of preterm birth on obstructive lung function deficits and COPD in the sixth decade of life was investigated for the first time. Screening studies for COPD in developed and low- and middle-income countries suggest the importance of tailoring screening strategies to local conditions. Developments in artificial intelligence provide a general framework for using machine-learning-based methods and medical record-based labels to improve disease prediction. New perspectives on endotypes/phenotypes and prognostic assessment of COPD were provided by lifetime spirometry patterns of obstruction and limitation, sensitisation to recombinant Aspergillus fumigatus allergens, airway-occluding mucus plugs and exacerbation history in COPD group A and B patients. Clinical trials focusing on inflammatory mediators, comorbidity treatment, non-pharmacological treatments, and environmental interventions shed light on some crucial and long-debated issues. Further research is needed for individualised diagnosis and treatment of COPD.

[Distribution and reference intervals of daytime intraocular pressure in the eye health screening population of Handan]

Objective: To describe the distribution and establish reference intervals (RI) of daytime intraocular pressure (IOP) in the eye health screening population of Handan. Methods: This cross-sectional study included subjects who participated in eye health screening at the Physical Examination Center of Handan First Hospital from May 2021 to June 2022. A complete general and ocular examination was performed, including measurements of visual acuity and IOP (using Goldmann tonometry), slit lamp microscopy, fundus photography, and anterior and posterior segment optical coherence tomography. Subjects with factors that could cause significant changes in IOP or affect the accuracy of IOP measurement, or with an inability to measure IOP were excluded. Simple random sampling was used to select participants, who were grouped by gender and age (18 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, and ≥70 years). Central corneal thickness and IOP at 8 to 11 o'clock in one eye of each participant were recorded. The independent sample t test and ANOVA were used for statistical analysis, and the RI of IOP values was calculated by x¯±1.96s. Results: A total of 9 310 subjects had their IOP measured, and 3 491 participants (3 491 eyes) were randomly selected from 7 886 healthy subjects. The age of the participants was (47.74±14.47) years old, ranging from 18 to 90 years old. There were 1 694 males and 1 797 females. The central corneal thickness of all participants was (525.56±49.39) μm. The daytime IOP of all participants was (15.40±2.54) mmHg (1 mmHg=0.133 kPa), and the RI was 10.42 to 20.39 mmHg. The IOP was (15.49±2.58) mmHg for males and (15.29±2.49) mmHg for females, and the gender difference was statistically significant (P<0.05). The RI of daytime IOP values was 10.43 to 20.54 mmHg for males and 10.41 to 20.18 mmHg for females. There were significant differences in daytime IOP [(15.13±2.58), (15.33±2.53), (15.49±2.50), (15.53±2.55), (15.39±2.62), and (15.28±2.52) mmHg] among 6 age groups (P<0.05). Conclusions: The distribution of daytime IOP in different gender and age groups in the eye health screening population of Handan and the RIs derived from the distribution were roughly the same as the international normal IOP RI (10 to 21 mmHg). It is recommended to refer to the RI of daytime IOP values of different genders and ages for clinical decision.

Oncologic safety of the pedicled submental island flap for reconstruction in oral tongue squamous cell carcinoma: An analysis of 101 cases

OBJECTIVE

To evaluate whether the pedicle submental island flap (SIF) can be safely used in the oral tongue squamous cell carcinoma (OTSCC) patients with pathologically node-positive (pN+) neck, especially pN+ at level I.

METHODS

Retrospectively, 101 OTSCC patients with SIF reconstruction were enrolled. Oncological outcomes included the total locoregional recurrence, the SIF related locoregional recurrence (SRLR) which referred to the local recurrence at flap and ipsilateral neck recurrence at level I, recurrence free survival (RFS), overall survival (OS), and disease specific survival (DSS).

RESULTS

Sixty-one patients were pathologically node-negative (pN0) and 40 were pN+. Thirteen patients experienced locoregional recurrence, of which 5 had a SRLR. The pN+ group had a significantly higher locoregional recurrence rate, lower 5-year RFS, OS and DSS than pN0 group (P < 0.05). Patients with pN0 had a significantly higher neck RFS when compared to those with pN+ either at level I (P = 0.005) or at other levels (P < 0.001). However, the neck RFS was similar between the two subgroups of pN+ (P = 0.550). Especially, patients with pN+ at level I had a significantly higher SRLR rate (P = 0.006) compared to those with pN0 at level I. Multivariate analysis showed that pN+ was an unfavorable factor for tumor recurrence and OS.

CONCLUSION

Our data did not support the use of SIF in OTSCC patients with pN+ neck at level I due to an significantly increased SRLR rate compared to those with pN0 neck at level I.

[Treatment of palbociclib in hormone receptor positive breast cancer: a real-world study and efficacy prediction model]

Objective: To summarize the clinical use of palbociclib and evaluate its efficacy and safety in hormone-receptor (HR)-positive advanced breast cancer patients. Methods: We retrospectively analyzed data from 66 HR-positive metastatic breast cancer patients treated with palbociclib and endocrine therapy at the Department of Oncology in the First Affiliated Hospital with Nanjing Medical University between 2018 and 2020. We evaluated the factors affecting the efficacy of palbociclib using Kaplan-Meier method and Log-rank test for survival analysis and Cox regressions for multivariate analysis. Nomogram model was built for predicting prognosis among HR-positive breast cancer patients who received palbociclib. Concordance index (C-index) and calibration curve were used for internal validation to assess the predictive ability and conformity of the model. Results: Of the 66 patients treated with palbociclib, 33.3%(22), 42.4%(28) and 24.2%(16) patients were treated without endocrine therapy, first-line endocrine therapy, second-line or above endocrine therapy after recurrence, respectively. 36.4%(24) patients had hepatic metastasis, 16.7% (11) patients were sensitive to previous endocrine therapy, 27.3%(18/66) patients had primary resistance to endocrine therapy, while 56.1% (37) patients had secondary resistance to endocrine therapy. The overall response rate was 14.3% (95% CI: 6.7%, 25.4%) and clinical benefit rate was 58.7% (95% CI: 45.6%, 71.0%). Better clinical outcomes were associated with non-hepatic metastasis (P=0.001), sensitive/secondary resistant to previous endocrine therapy (P=0.004), no or only one line of chemotherapy for metastatic breast cancer (P=0.004), recent pathological confirmation of immunohistochemical analysis (P=0.025). Hepatic metastasis (P=0.005) and primary resistance to endocrine therapy (P=0.016) were the independent risk factors of progression free survival. The C-index of predictive probability for the nomogram constructed from the patient clinical characteristics (whether liver metastasis, whether primary endocrine resistance, lines of chemotherapy after metastasis, lines of endocrine therapy, number of metastatic sites, and time to last immunohistochemistry) to predict the progression-free survival at 6 and 12 months for patients was 69.7% and 72.1%, respectively. The most common adverse events were hematologic toxicities. Conclusions: Our report indicates that palbociclib combined with endocrine therapy for HR-positive recurrent metastatic breast cancer is effective and safe; patients with hepatic metastases and primary resistance to endocrine therapy have worse prognoses and are independent risk factors for progression after palbociclib therapy. The constructed nomogram could help predict the survival and guide the use of palbociclib.

[Effect of hemoperfusion on protein energy wasting and long-term prognosis in patients on maintenance hemodialysis]

Objective: To explore the effect of hemoperfusion (HP) combined with hemodialysis (HD) (HD+HP) on protein energy wasting (PEW) and long-term prognosis in patients on maintenance HD (MHD). Methods: A prospective multicenter cohort study was conducted. Adult MHD patients who completed PEW assessment and underwent regular dialysis between July 2015 and July 2021 at 23 hemodialysis centers in Guizhou Province were selected. Demographic characteristics, physical indicators, laboratory indicators, 3-day diet diary and HP treatment data of the subjects were collected. The patients were divided into different groups according to the presence or absence of HP, the frequency of HP treatment and the type of cartridge, and then relevant indicators were compared. Multivariate logistic regression model and Cox proportional regression model were used to analyze the influence of HP treatment on PEW risk in MHD patients. Meanwhile, Kaplan-Meier method was used to plot the survival curve. Results: A total of 4 623 MHD patients (2 789 males and 1 834 females) aged (53.7±15.9) years were included in the study, with a median dialysis age of 64.3 (44.3, 92.3) months. There were 3 429 (74.2%) MHD patients treated with HD+HP, and 1 194 patients (25.8%) were not treated with HP. According to the 2008 diagnostic criteria of the International Society for Renal Nutrition and Metabolism (ISRNM), the incidence of PEW was 26.0% (1 204/4 623). Multivariate logistic regression analysis showed that female (OR=2.48, 95%CI: 1.55-3.95, P<0.001), diabetes (OR=1.75, 95%CI: 1.08-2.83, P=0.024) and high-sensitivity C-reactive protein (hs-CRP) (OR=1.02, 95%CI: 1.01-1.03, P=0.003) were risk factors for PEW, while treatment with HD+HP (OR=0.51, 95%CI: 0.31-0.87, P=0.012) and elevated triglyceride levels (OR=0.62, 95%CI: 0.48-0.80, P<0.001) were protective factors. Cox hazard ratio regression showed that among different HP treatment frequencies and cartridge types, 2 times/month (HR=0.40, 95%CI: 0.17-0.95, P=0.037), 3 times/month (HR=0.44, 95%CI: 0.23-0.85, P=0.014), 4 times/month (HR=0.54, 95%CI: 0.34-0.85, P=0.008), HA130 (HR=0.57, 95%CI: 0.36-0.89, P=0.014) and HA230 (HR=0.30, 95%CI: 0.15-0.63, P=0.001) had protective effects on the occurrence of PEW in MHD patients. The all-cause mortality rate was 11.3% (521/4 623) at 33 (24, 48) months of follow-up. Kaplan-Meier analysis showed that patients undergoing 4 times/month HP treatment (χ²=36.78, P<0.001) and using HA230 (χ²=9.46, P=0.002) had the highest survival rate. Conclusion: Treatment with HD+HP is a protective factor for PEW in patients with MHD, and 4 times/month HP treatment or HA230 significantly reduces the risk of PEW and all-cause mortality in patients with MHD.

[Effects of special natural environments and mechanisms on intraocular pressure]

With the expansion of human exploration and activities, increasing people work and live in special natural environments with relatively unique characteristics, which can not only lead to pathophysiological changes and metabolic disorders, but also have a great impact on eyes and intraocular pressure (IOP). This article reviews the effects of the high-altitude hypoxia environment, space microgravity environment, deep water environment, dark environment, cold environment and ambient air pollution on IOP, and discusses the mechanisms of related IOP changes.

[Comparison study for the proportion of underdiagnosed zonulopathy in angle closure glaucoma]

Objective: To analyze the proportion and clinical characteristics of underdiagnosed zonulopathy in angle closure glaucoma (ACG) patients and to explore the related risk factors. Methods: Case-control study. Continuous cases of ACG patients who underwent phacoemulsification combined with intraocular lens implantation and goniosynechialysis surgery [ACG group, including acute angle closure glaucoma (AACG) and chronic angle closure glaucoma (CACG)] from November 1, 2020 to October 31, 2021 and age-related cataract patients who underwent phacoemulsification combined with intraocular lens implantation surgery in the same period (control group) were included. The diagnosis of zonulopathy was determined according to the intraoperative signs such as wrinkles of the anterior capsule during continuous circular capsulorhexis. The proportion of zonulopathy, preoperative diagnosis rate of zonulopathy, demographic characteristics, anterior chamber depth (ACD), axis length, difference of ACD in both eyes (ACD of the contralateral eye minus ACD of the operated eye) were compared between the two groups. The related risk factors were explored. The paired t-test (comparison between two groups of normally distributed data), non-parametric test (comparison between two groups of non-normally distributed data), Chi-square test (categorical variables), univariate and multivariate logistic regression analysis were used. Results: There were 104 ACG patients (104 eyes), including 63 AACG patients (63 eyes) and 41 CACG patients (41 eyes), and 117 controls (117 eyes). There was no significant difference in age (P=0.29) and gender (P=0.07) between the two groups. The ACG group had shallower anterior chamber (P<0.001), shorter axial length (P<0.001) and more ACD difference in both eyes (P<0.001). In the ACG group, the proportion of zonulopathy was 46.2% (48/104), which was significantly higher than that (6.0%, 7/117) in the control group (P<0.001). In the control group, only zonular laxity was found, while in the ACG group, besides the predominant zonular laxity (68.8%, 33/48), there was zonular dehiscence (31.3%, 15/48). The eyes with AACG (57.1%, 36/63) had a higher proportion of zonulopathy than those with CACG (29.3%, 12/41) (P=0.006). In the ACG group, only 14 cases (29.8%) were diagnosed preoperatively according to slit lamp examination and/or ultrasound biomicroscopy. The proportion of underdiagnosed zonulopathy was 70.8% in the ACG group (34/48). A smaller ACD was found to be related to the zonulopathy in the ACG group. All AACG cases with an ACD ≤2.0 mm and CACG cases with an ACD ≤1.9 mm had zonulopathy. Multivariate logistic regression showed that the ACD difference in both eyes (P=0.025) and the diagnosis of ACG (AACG vs. cataract, P<0.001; CACG vs. cataract, P=0.023) were independent risk factors associated with zonulopathy. Conclusions: The proportion of underdiagnosed zonulopathy among ACG patients is high. Better preoperative diagnostic methods for zonulopathy are needed. Zonulopathy is common in ACG patients, especially in AACG patients, suggesting that zonulopathy may be related to the pathogenesis of ACG. The shallower the ACD, the riskier the zonulopathy. ACD differences between two eyes and ACG types (including AACG and CACG) were related risk factors of zonulopathy.(This article was published ahead of print on the Online-First Publishing Platform for Excellent Scientific Researches of Chinese Medical Association Publishing House on March 11, 2022).

[Interactive effect of hypoparathyroidism and type 2 diabetes mellitus on peritoneal dialysis related peritonitis]

Objective: To investigate the interactive effect of hypoparathyroidism (HPTH) and type 2 diabetes mellitus (T2DM) on peritonitis in patients on peritoneal dialysis (PD). Methods: In this retrospective cohort study, all PD patients who were firstly catheterized in the peritoneal dialysis center of Guizhou Provincial People's Hospital from January 1, 2012 to December 31, 2018 were included. The characteristics of demographics, baseline clinical and laboratory data were collected, and patients were followed up until December 31, 2020. Kaplan-Meier survival curve and Cox regression analysis were used to explore the associations between the interaction of HPTH+T2DM and peritonitis. Results: A total of 270 PD patients were enrolled in this study, aged (39.9±13.2) years, including 143 males and 24 T2DM patients. These serum levels of intact parathyroid hormone (iPTH) [M(Q₁, Q₃)] was 268.1 (121.7, 447.0)pg/ml. After a median follow-up of 29.5 (range from 4.0 to 75.0) months, peritonitis occurred in 69 (25.6%) PD patients for the first time. After controlling for confounding factors, the interaction analysis showed that the risk of peritonitis in T2DM patients with HPTH (n=12) was 3.48 times that of non-T2DM patients without HPTH (n=180) (HR=3.48, 95%CI: 1.04-3.87, P=0.034), which was also greater than the sum of the factors alone (HR=1.35, 95%CI: 0.78-2.31 and HR=0.82, 95%CI: 0.20-3.40). The synergy index between HPTH and T2DM was 1.95, the attributable proportion of interaction was 67.6%, and the relative excess risk of interaction was 2.35. The receiver operating characteristic (ROC) curve indicated that the area under the curve of combined diagnosis of HPTH and T2DM was 0.626 (95%CI: 0.550-0.703, P=0.039). Conclusion: The positive interaction between HPTH and T2DM is an independent risk factor for peritonitis in PD patients, both of which can significantly increase the risk of peritonitis.

[Nomogram model for predicting risk of anti-tuberculosis drug-induced liver injury among inpatients with tuberculosis]

Objective: To explore the influencing factors of anti-tuberculosis drug-induced liver injury (ATB-DILI) in hospitalized tuberculosis patients, and to establish a risk prediction model of Nomogram. Methods: A retrospective study was conducted on 5 681 tuberculosis patients admitted to Guiyang public health treatment center from January 2017 to June 2021, including 3 342 males and 2 339 females. The inpatients with ATB-DILI were selected as the case group (214 cases) and the non-ATB-DILI patients as the control group (5 427 cases). The baseline characteristics, tuberculosis condition, behavior and disease-related data of the patients were retrospectively analyzed, and the influencing factors were screened by chi-square test and multivariate logistic regression, based on which the Nomogram model was constructed and verified. The decision curve was used to evaluate the clinical application value of the model. Results: In this study, 3.8%(214/5 681) patients developed ATB-DILI. Multivariate logistic regression analysis showed that extrapulmonary tuberculosis (OR=1.876, P<0.001), malnutrition (OR=4.411, P<0.001), complicated with underlying liver disease (OR=4.961, P<0.001) and intermittent use of hepatoprotective drugs (OR=2.137, P=0.007) were independent risk factors for ATB-DILI, while whole-course use of hepatoprotective drugs (OR=0.292, P<0.001) was protective factor. The Nomogram model was constructed based on the above five related factors. The area under the receiver operating characteristic (ROC) curve was 0.749 (95%CI:0.713-0.786), the sensitivity was 0.640, and the specificity was 0.752, respectively. The Bootstrap method was used for internal repeated sampling for 1 000 times, the average absolute error was 0.003, the correction curve and the ideal curve were basically fitted, and the predicted values were in good agreement with the actual values. Hosmer-lemeshow test showed that the model had a good degree of fit (χ²=3.068, P=0.381). The decision curve showed that the Nomogram model had certain clinical practicability in the high risk threshold range (0.10-0.68). Conclusions: The Nomogram model for risk predicting ATB-DILI among inpatients with tuberculosis in this study has good predictability, consistency and clinical practicability, and can provide a basis for clinical prevention and control of ATB-DILI and individualized treatment in the process of anti-tuberculosis treatment.

[Occurrence and recurrence of hepatitis C-related hepatocellular carcinoma after direct antiviral treatment]

Hepatitis C virus (HCV) RNA can be cleared from the blood circulation by direct antiviral treatment to achieve sustained virologic response (SVR). Studies have shown that SVR after direct antiviral therapy can reduce the incidence of hepatocellular carcinoma; however, monitoring for hepatocellular carcinoma is still needed. This review briefly summarizes and discusses the existing studies on the possible causes of hepatitis C secondary to HCC after antiviral therapy, which is mainly divided into epigenetic alterations and abnormal DNA methylation, HCV-related cirrhosis and abnormal DNA amplification, HBV reactivation, several aspects of occult HCV infection, and the effect of direct antiviral treatment on hepatocellular carcinoma recurrence. In few cases, direct antiviral treatment cannot completely prevent the occurrence and recurrence of hepatitis C-related hepatocellular carcinoma. Therefore, its mechanism needs to be studied and explored, and clinicians should also approach it with caution.

[Analysis of the factors influencing the elimination strategies with the current status of diagnosis and treatment of hepatitis C in hospital]

Objective: To understand the current status of screening, diagnosis, and treatment and analyze the factors influencing micro-elimination strategy, so as to achieve hepatitis C elimination in hospital. Methods: Anti-HCV and HCV RNA test results of patients from October 2017 to September 2020 were retrospectively analyzed. Anti-HCV positive rates and factors influencing different genders, ages, places of residence and departments were analyzed. After comparing anti-HCV-positive patients with HCV RNA-positive patients with duplicate entries in "Name" and "Date of birth", the data were divided into three categories: anti-HCV positive without HCV RNA test, HCV RNA positive in single test, and HCV RNA positive many times in multiple tests. The above three types of patients were followed-up by telephone. According to the hospital follow-up results, current status of diagnosis and treatment and the factors influencing the micro-elimination strategy of hepatitis C were studied and analyzed. The comparison of data between groups were performed using χ(2) or χ(2) continuity-correction test. Results: Anti-HCV positive detection rate was 1.34% (899/66 866). The positive rate of male patients aged 40 and over residing in cities was significantly higher than female patients under 40 years old residing in rural areas, and the difference was statistically significant (χ(2) = 55.178, 264.11, 36, 351, P < 0.05). There were 90 (10.02%) and 809 cases (89.98%) in outpatient and inpatient departments, respectively, with no statistically significant difference between the two (χ(2) = 0.002, P > 0.05). The total number of anti-HCV positive cases were 196 in Gastroenterology (22.0%), 75 in Respiratory and Critical Care Medicine (8.3%), 74 in Neurology (8.2%), 63 in Orthopedics (7.0%) and 55 in Endocrinology departments (6.1%), and the difference in the positive rate among different departments were also statistically significant (χ(2) = 271.585, P < 0.05). Among the 480 cases who were followed-up, 215 (44.79%) were lost to follow-up, 84 cases (39.07%) were unregistered, 77 cases (16.04%) were untreated, 15 cases (19.48%) were unaware of their state of illness, 46 cases (59.74%) were diagnosed without concern, 16 cases (20.78%) were diagnosed but did not take medicine, 60 cases were under treatment, and 29 cases were mostly on counterfeit drugs (48.33%). Conclusion: Comprehensive diagnosis and treatment education to non-specialist clinicians and timely manner regular follow-up of patients is a key factor and an important link to formulate a simple, easy and sustainable model to improve the efficiency of screening, diagnosis, and treatment of hepatitis C micro-elimination strategy in hospital. In addition, it will also play an important role in achieving the strategic goal of "eliminating hepatitis C as a public health threat by 2030".

[Current status of thromboembolism risk assessment in patients hospitalized with non-valvular atrial fibrillation in tertiary hospitals in China]

Objective: To analyze the current status, trend and predictors of thromboembolism risk assessment in patients hospitalized with non-valvular atrial fibrillation (NVAF) in tertiary hospitals in China. Methods: The study was based on data from the Improving Care for Cardiovascular disease in China (CCC)-Atrial Fibrillation (AF) project. About 10% of the tertiary hospitals in each geographic-economic stratum were recruited. Participating hospitals reported the first 10 to 20 patients with a discharge diagnosis of atrial fibrillation monthly. From February 2015 to December 2019, a total of 49 104 NVAF patients from 151 tertiary hospitals in 30 provinces, municipalities and autonomous regions were enrolled. Clinical data of the patients was collected. The proportion of NVAF patients receiving thromboembolism risk assessment, variations in the proportion between different hospitals, the time trend of the application of thromboembolism risk assessment, and the predictors of the application of thromboembolism risk assessment were analyzed. Results: The age of the NVAF patients was (68.7±12.1) years, 27 709 patients (56.4%) were male. Only 17 251 patients (35.1%) received thromboembolism risk assessment. The proportion varied substantially between hospitals with the lowest value of 0 and the highest value of 100%. Among the hospitals, which enrolled more than 30 patients, no patients received thromboembolism risk assessment in 18.4% (26/141) of the hospitals, more than 50% of the patients received thromboembolism risk assessment in 21.3% (30/141) of the hospitals, and all the patients received thromboembolism risk assessment in only 1 hospital. The proportion of NVAF patients receiving thromboembolism risk assessment was 16.2% (220/1 362) in the first quarter of 2015, and significantly increased to 67.1% (1 054/1 572) in the last quarter of 2019 (P<0.001). Patients' characteristics were associated with the application of thromboembolism risk assessment. The odds of receiving thromboembolism risk assessment was lower in male patients compared to female patients(OR=0.94,95%CI 0.89-0.99), lower in patients with acute coronary syndrome or other cardiovascular diseases compared to those with AF as the primary admission reason (OR=0.59, 95%CI 0.55-0.63, OR=0.52, 95%CI 0.45-0.61, respectively), and lower in patients with paroxysmal, persistent and long-standing/permanent AF compared to those with first detected AF (OR=0.62, 95%CI 0.57-0.67, OR=0.72, 95%CI 0.66-0.79, OR=0.57, 95%CI 0.52-0.64, respectively). The odds was higher in patients with a history of hypertension, heart failure, stroke/TIA, and previous anticoagulant therapy compared to those without the above conditions (OR=1.17, 95%CI 1.11-1.23, OR=1.18, 95%CI 1.07-1.30, OR=1.17, 95%CI 1.08-1.27, OR=1.28, 95%CI 1.19-1.37, respectively) (P all<0.05). Conclusion: Thromboembolism risk assessment was underused in patients hospitalized with NVAF in tertiary hospitals in China, and there were substantial variations between hospitals in the application of thromboembolism risk assessment. The application of thromboembolism risk assessment in tertiary hospitals has been improved in recent years, but there is still plenty of room for future improvement. Patients' characteristics could affect the application of thromboembolism risk assessment in China.

Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

[Airborne pollens in Wuhan urban area and its correlation with hospital visits of allergic rhinitis patients from 2017 to 2018]

Objective: To investigate the species and concentrations of airborne pollens in Wuhan urban area and their correlation with the number of visits of allergic rhinitis patients. Methods: Retrospective analysis of pollen dispersal characteristics and the number of patients with allergic rhinitis presenting to Tongji Hospital of Huazhong University of Science and Technology in Wuhan city from October 2017 to September 2018, as well as pollen allergen testing results of patients with allergic rhinitis presenting to the Department of Allergy during the same period. Pollen data was collected by a 1-year air sampling conducted in Wuhan City during the same period using the volumetric method. The samples were examined microscopically to identify airborne pollen species and counted, and the concentrations of various pollens were calculated. Information on patients with allergic rhinitis who came to the hospital during the same period was collected, and the correlation between pollen concentration and the number of patient visits was statistically analyzed using Pearson correlation analysis. Results: A total of 35 types of airborne pollen were collected from October 2017 to September 2018. The dominant pollens in spring were Moraceae (68.46%, 1 042/1 522), Pendula (12.22%, 186/1 522) and Cupressaceae (2.30%, 35/1 522); in summer and autumn, the dominant pollens were Artemisia (3.81%, 58/1 522), Humulus (4.01%, 61/1 522) and Ambrosia (0.59%, 9/1 522). The peak number of visits for allergic rhinitis patients occurred in March-April and July-September, both exceeding 2 200 visits and reaching a maximum of 2 545 visits. There was a very weak correlation between the number of visits and the total pollen concentration (r=0.17, P=0.001). The average monthly pollen skin prick test positive rate of patients with allergic rhinitis was highest in March-May, exceeding 40% with a maximum of 45.73%, and there was a significant correlation between the positive pollen skin prick test positive rate and the average monthly pollen concentration (r=0.62, P=0.031). Conclusions: Pollen species and concentrations fluctuated continuously with time in Wuhan urban area, with peak pollen dispersal in spring from March to April and in autumn from August to September. The number of visits to patients with allergic rhinitis and the positive pollen skin prick test positive rate increased accordingly during the peak pollen concentration periods.

[Application and thinking of health standards related to medical care and health information in prevention and control of COVID-19]

Objective: To compare the technical elements of health standards for nosocomial infection control, health protection, health information, and health emergency and biosafety in the context of the prevention and control of COVID-19, and provide support for the further optimization of the epidemic prevention and control guidelines. Methods: Above mentioned health standards used in COVID-19 prevention and control were collected for a systematic comparison with "Guidelines for Prevention and Control of COVID-19 in Medical Institutions" (the 1(st) Edition) from the perspective of technical elements. Results: The application scope and technical elements of the current health standards basically meet the needs for the prevention and control of COVID-19 epidemic. Conclusions: The implementation of the current health standards can provide strong technical support for the prevention and control of COVID-19 epidemic. The experience obtained in the epidemic prevention and control can also contribute to the further revision and improvement of the health standards.

Biological Characteristics and Genetic Diversity of Phomopsis asparagi, Causal Agent of Asparagus Stem Blight

Asparagus stem blight is a regional disease. In the present study, we compared strains of Phomopsis asparagi from six different provinces to determine their biological characteristics and genetic diversity, differences in the pycnidium and conidium production, pathogenicity, and growth rate. Considerable differences were established in the pycnidium and conidium production among the P. asparagi strains from the six studied provinces. The largest pycnidium and conidium production had the strains from Fujian, followed by those from Hainan. The virulence of P. asparagi strains was significantly different but without a correlation with the geographical source of the strain. FJ2 had the highest virulence, followed by HN2, SD4, and SD5, whereas SD5 had the lowest virulence. The colony diameter and dry weight of the strains of asparagus stem blight fungus from the six provinces were substantially different. The colonies of HN1-5 had the largest diameters, whereas those of XT1-5, LT1-3, FJ1-5, and SX6 had smaller diameters. Four primers with good repeatability and strong specificity were selected from 100 intersimple sequence repeat (ISSR) primers. ISSR-PCR amplification was performed on 36 strains of asparagus stem blight fungus, and a large number of repeatable DNA fingerprints were obtained. Most of the amplified fragments were within 300 to 500 bp. In all, 69 total points, 64 multiple points, and 92.75% polymorphism points were established. The number of ISSR gene sites detected by four primers ranged from 14 to 20, with an average of 16 multiple sites. The copolymerization was divided into three groups: XT1-5, LT1-3, and FJ1-5, which were clustered into the first group; SD1-6, SX1-6, and HB1-6, clustered into the second group; and HN1-5 in the third group. The results of the cluster analysis revealed that the strains of the neighboring provinces had a nearer phylogenetic relationship than that between distant ones. Therefore, the system evolution of P. asparagi is related to the geographical distribution of its strains.

[Association between serum levels of osteopontin and systolic pulmonary artery pressure among healthy adults post acute high altitude exposure]

Objective: To explore the association between serum levels of osteopontin (OPN) and systolic pulmonary artery pressure (sPAP) in healthy men following acute high altitude exposure. Methods: According to the inclusion and exclusion criteria, this observational study included 94 male subjects (aged from 18 to 30 years, dwelling in lowland<500 m) who ascended to Litang (4 100 m) from Chongqing (400 m) by bus with a stair-like journey within 7 days in June 2013. Data including basic information, OPN, superoxide dismutase (SOD), and malondialdehyde (MDA) and echocardiographic derived sPAP were collected within 48 hours before ascent and within 2-7 hours after arrival. Accordingly, subjects were divided into 3 groups based on the tertiles of sPAP after acute high altitude exposure: low sPAP group (26.8-32.3 mmHg (1 mmHg=0.133 kPa)) (n=31), middle sPAP group (32.4-37.4 mmHg) (n=32) and high sPAP group (37.5-55.6 mmHg) (n=31). Associations of serum OPN and SOD levels with sPAP were analysed by univariate and multivariate linear regression analysis. Results: After acute high altitude exposure, the levels of sPAP were significantly increased (P<0.001). There were no differences in age, height, weight, body mass index, percent of Han nationality and smoking among 3 subgroups. However, following acute high altitude exposure, the levels of heart rate, systolic and diastolic blood pressure elevated (all P<0.05), whereas the levels of oxygen saturation were reduced in the total subjects and all subgroups (all P<0.05). Moreover, systolic blood pressure of subjects in the high sPAP group was higher than that in low and middle sPAP groups (both P<0.05), and diastolic blood pressure of subjects in high sPAP group was higher than that in low sPAP group (P<0.05). The serum levels of OPN were increased in total cohort(27.9 (22.5,34.0) μg/L vs. 25.6 (18.4, 33.1) μg/L, P<0.05)， and high sPAP group (P<0.05), whereas no differences were found in serum SOD and MDA levels among groups. Furthermore, the serum level of OPN in high sPAP group was higher than that in low sPAP group at high altitude (P<0.05), and there was a trend for decline in SOD level with increasing sPAP (P>0.05). Results from univariable linear regression analysis showed that the serum levels of OPN (r=0.32, P=0.002) and SOD (r=-0.22，P=0.032) were linearly correlated with sPAP in total cohort after high altitude exposure. Multivariate regression analysis showed that the serum levels of OPN(β=0.310，P=0.002) and SOD (β=-0.199，P=0.043) were independently associated with the levels of sPAP at high altitude. Conclusion: After acute high altitude exposure, the serum level of OPN is positively associated with sPAP, suggesting that OPN may be a novel bio-marker for predicting the increase of pulmonary pressure in response to acute high altitude exposure.

Tripterygium glycoside fraction n2: Alleviation of DSS-induced colitis by modulating immune homeostasis in mice

BACKGROUND

The Tripterygium glycosides (TG) is the main active extractive of Tripterygium wilfordii Hook F and is widely used in clinical practice to treat inflammatory diseases (including inflammatory bowel disease). However, due to its severe toxicity, TG is restricted to the treatment of many diseases. Therefore, it is necessary to study a new method to obtain the attenuated and synergistic extracts from TG.

PURPOSE

Tripterygium glycosides-n2 (TG-n2) was obtained from TG by a new preparation method. In this study, we aimed to investigate the difference in the chemical compositions between TG and TG-n2, further explored its toxicity and therapeutic effects on DSS-induced colitis in mice.

METHODS

The major chemical compositions of TG and TG-n2 were analyzed by ultra-performance liquid chromatography (UPLC). Subsequently, acute toxicity test was applied to evaluate the toxicity difference between TG and TG-n2. Dextran sulfate sodium (DSS)-induced acute colitis model was used to explore the therapeutic effect of TG and TG-n2 and their potential mechanisms of action.

RESULTS

We found that the chemical compositions of TG-n2 is different from TG. The main difference is the ratio of triptriolide (T11) / triptolide (T9). Acute toxicity test proved that TG-n2 was less toxic than TG. Base on this, further studies showed that TG-n2 has a similar therapeutic effect as compared to TG on attenuating the symptoms of colitis, such as diarrhea, bloody stools, body weight loss, colonic atrophy, histopathological changes, inhibiting cytokines secretion and reducing absolute lymph number. In addition, TG and TG-n2 can increase the apoptosis of T lymphocyte in vivo. Further investigated showed that TG and TG-n2 could increase the expressions of Bax and p62 on CD3-positive T cells.

CONCLUSION

This study showed that oral administration of TG-n2 is safer than TG. Moreover, the attenuated TG-n2 has the similar therapeutic effect on treating experimental colitis in mice when compared to TG. Its mechanism may be related to activating the expression of Bax in T cells and inducing T cells autophagy to regulate the survival of T lymphocytes in colitis mice, thus reducing inflammation in colon.

[Efficacy and safety of immunotherapy in dust mites andalternaria multi-sensitized allergic rhinitis patients]

Objective:The aim of this study is to evaluate the efficacy and safety of immunosuppression in patients with allergic rhinitis with multiple sensitization of dust mites and Alternaria.Method:An open, label random parallel controlled clinical study was conducted. Sixty dust mites and alternaria multi-sensitized allergic rhinitis patients were enrolled and randomized into immunotherapy group and medication group.Evaluation indicators included symptom scores, medication scores,symptom medication combined scores,RQLQ and serum allergen-specific IgE.In immunotherapy group, side effects were also observed and recorded.Result:After 24 months of treatment, all the scores were significantly lower than baseline,in both immunotherapy group and medication group.The scores of immunotherapy group were significantly lower than those of the medication group. Only local side effects were observed in immunotherapy group,without any systemic side effects and anaphylaxis.Conclusion: Mixed immunotherapy with dust mites and alternaria was effective and safe in allergic rhinitis patients and it had better curative effect than medication.

Fisetin Exerts Antioxidant and Neuroprotective Effects in Multiple Mutant hSOD1 Models of Amyotrophic Lateral Sclerosis by Activating ERK

Oxidative stress exhibits a central role in the course of amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease commonly found to include a copper/zinc superoxide dismutase (SOD1) gene mutation. Fisetin, a natural antioxidant, has shown benefits in varied neurodegenerative diseases. The possible effect of fisetin in ALS has not been clarified as of yet. We investigated whether fisetin affected mutant hSOD1 ALS models. Three different hSOD1-related mutant models were used: Drosophila expressing mutant hSOD1^G85R, hSOD1^G93A NSC34 cells, and transgenic mice. Fisetin treatment provided neuroprotection as demonstrated by an improved survival rate, attenuated motor impairment, reduced ROS damage and regulated redox homeostasis compared with those in controls. Furthermore, fisetin increased the expression of phosphorylated ERK and upregulated antioxidant factors, which were reversed by MEK/ERK inhibition. Finally, fisetin reduced the levels of both mutant and wild-type hSOD1 in vivo and in vitro, as well as the levels of detergent-insoluble hSOD1 proteins. The results indicate that fisetin protects cells from ROS damage and improves the pathological behaviors caused by oxidative stress in disease models related to SOD1 gene mutations probably by activating ERK, thereby providing a potential treatment for ALS.

[A novel HAND1 mutation associated with sporadic dilated cardiomyopathy]

Objective: To investigate a novel mutation in the HAND1 gene associated with sporadic dilated cardiomyopathy (DCM). Methods: From February 2013 to February 2017, the clinical data and peripheral venous blood samples were collected from 120 patients with sporadic DCM and 200 healthy controls, who were both from the Fifth People's Hospital of Shanghai, Fudan University and Shanghai Chest Hospital, Shanghai Jiaotong University.The genomic DNA was extracted from the study participants.The coding exons of HAND1 were amplified from the study subjects by polymerase chain reaction, and were sequenced for a potential HAND1 mutation.The online computer programs MUSCLE and Mutation Taster were used to analyze the conversation of an altered amino acid and to predict the disease-causing potential of an identified mutation, respectively.The wild-type HAND1 was cloned and the mutant was generated by site-directed mutagenesis.The Dual-luciferase reporter assay kits were used to explore the functional characteristics of the mutant HAND1. Results: A novel heterozygous mutation, a substitution of thymine for guanine at nucleotide 346 (c.346G>T), predicting the conversion of a glutamic acid-encoding codon into a stop codon at codon 116 (p.E116X), was detected in a patient with sporadic DCM.The nonsense mutation was absent in the 200 control individuals.The altered glutamic acid at amino acid position 116 was highly conserved evolutionarily, and the mutation was predicted to be pathogenic.Biological analyses revealed that the mutant HAND1 lost the ability to transcriptionally activate a target gene. Conclusion: Loss-of-function mutation in HAND1 is likely to be an uncommon cause responsible for sporadic DCM.

[Clinical analysis of rituximab-induced interstitial lung disease]

Objective: To investigate the clinical characteristics, diagnosis-treatment points and prognosis of rituximab-induced interstitial lung disease (R-ILD), and to improve the recognition of this disease. Methods: The clinical data on 4 cases of R-ILD were analyzed retrospectively, and the related literatures were reviewed. The literature review was carried out respectively in Wanfang Data, CNKI and PubMed by October 2016 with"rituximab"and"interstitial lung disease"or"interstitial pneumonitis"as the search terms. Results: The all 4 patients received chemotherapy including rituximab, had respiratory symptoms after 2 to 5 cycles chemotherapy respectively. The chest computerized tomography findings of all 4 cases showed diffuse ground glass opacities. In all of the patients, the diagnosis of R-ILD was made and glucocorticoids therapy was initiated. After treatment, the clinical symptoms improved promptly and follow-up chest computerized tomography showed pulmonary lesions significantly resolved. Literature review found 48 articles (2 reviews, 6 original articles, 39 case reports and 1 other article) . 50 cases of R-ILD were collected and the chief complaint were dyspnea, cough and fever. The ground-glass pattern on the CT scan of the chest was the important feature of this disease. Therapy included glucocorticoids, discontinuation of rituximab, and any other clinically necessary measures. Conclusions: Rituximab can cause interstitial lung disease. The diagnosis relies on clinical manifestation and radiological findings. The good prognosis depends on prompt discontinuation of rituximab and treatment with glucocorticoids.

Inhibition of TGF-β Signaling in SHED Enhances Endothelial Differentiation

Low efficiency of deriving endothelial cells (ECs) from adult stem cells hampers their utilization in tissue engineering studies. The purpose of this study was to investigate whether suppression of transforming growth factor beta (TGF-β) signaling could enhance the differentiation efficiency of dental pulp-derived stem cells into ECs. We initially used vascular endothelial growth factor A (VEGF-A) to stimulate 2 dental pulp-derived stem cells (dental pulp stem cells and stem cells from human exfoliated deciduous teeth [SHED]) and compared their differentiation capacity into ECs. We further evaluated whether the vascular endothelial growth factor receptor I (VEGF-RI)-specific ligand placental growth factor-1 (PlGF-1) could mediate endothelial differentiation. Finally, we investigated whether the TGF-β signaling inhibitor SB-431542 could enhance the inductive effect of VEGF-A on endothelial differentiation, as well as the underlying mechanisms involved. ECs differentiated from dental pulp-derived stem cells exhibited the typical phenotypes of primary ECs, with SHED possessing a higher endothelial differentiation potential than dental pulp stem cells. VEGFR1-specific ligand-PLGF exerted a negligible effect on SHED-ECs differentiation. Compared with VEGF-A alone, the combination of VEGF-A and SB-431542 significantly enhanced the endothelial differentiation of SHED. The presence of SB-431542 inhibited the phosphorylation of Suppressor of Mothers Against Decapentaplegic 2/3 (SMAD2/3), allowing for VEGF-A-dependent phosphorylation and upregulation of VEGFR2. Our results indicate that the combination of VEGF-A and SB-431542 could enhance the differentiation of dental pulp-derived stem cells into endothelial cells, and this process is mediated through enhancement of VEGF-A-VEGFR2 signaling and concomitant inhibition of TGF-β-SMAD2/3 signaling.

Structure of A-C Type Intervariant Interface in Nonmodulated Martensite in a Ni-Mn-Ga Alloy

The structure of A-C type intervariant interface in nonmodulated martensite in the Ni54Mn25Ga21 alloy was studied using high resolution transmission electron microscopy. The A-C interface is between the martensitic variants A and C, each of which has a nanoscale substructure of twin-related lamellae. According to their different thicknesses, the nanoscale lamellae in each variant can be classified into major and minor lamellae. It is the boundaries between these lamellae in different variants that constitute the A-C interface, which is thus composed of major-major, minor-minor, and major-minor lamellar boundaries. The volume fraction of the minor lamellae, λ, plays an important role in the structure of A-C interfaces. For major-major and minor-minor lamellar boundaries, they are symmetrical or asymmetrical tilt boundaries; for major-minor boundary, as λ increases, it changes from a symmetrical tilt boundary to two asymmetrical microfacets. Moreover, both lattice and misfit dislocations were observed in the A-C interfaces. On the basis of experimental observations and dislocation theory, we explain how different morphologies of the A-C interface are formed and describe the formation process of the A-C interfaces from λ ≈ 0 to λ ≈ 0.5 in terms of dislocation-boundary interaction, and we infer that low density of interfacial dislocations would lead to high mobility of the A-C interface.

Expression of Magnaporthe oryzae genes encoding cysteine-rich proteins secreted during nitrogen starvation and interaction with its host, Oryza sativa

Previous studies have shown that the blast fungus, Magnaporthe oryzae, may experience nitrogen starvation during infection of its plant host (rice,Oryza sativa). Here, we studied the expression of seven genes encoding cysteine-rich proteins with N-terminal signal peptides during nitrogen limitation and throughout the infection process. Some genes were upregulated to a greater extent in weak pathogenic strains than in strong pathogenic strains when they were cultured in complete media, and the expression of some genes was higher in both weak and strong pathogenic strains cultured in 1/10-N and nitrogen starvation media. Furthermore, the expression of these genes was upregulated to different extents in the early stages of M. oryzae infection. These data demonstrate that the genes of interest are highly expressed in weak and strong pathogenic strains cultured under nitrogen limitation and at the early stage of the infection process. This indicates that cysteine-rich secreted proteins in the blast fungus might be involved in establishing disease in the host and that they are sensitive to nitrogen levels. Thus, their role in sensing nitrogen availability within the host is implied, which provides a basis for further functional identification of these genes and their products during plant infection.

Upregulation of fibroblast growth factor 1 in the synovial membranes of patients with late stage osteoarthritis

Osteoarthritis (OA) is a degenerative disease of the systemic joint that involves multiple cytokines and growth factors. Fibroblast growth factor 1 (FGF-1) is increased in patients with rheumatic arthritis. The aim of this study was to determine whether the expression and secretion of FGF-1 differed in synovial tissue from patients with late stage OA from that in normal tissues. We selected eight patients with late stage OA and eight healthy donors for this study. An enzyme-linked immunosorbent assay was used to determine the amount of FGF-1 in the synovial fluid and in the culture medium of synovial fibroblasts. Real time quantitative polymerase chain reaction (qPCR) analysis was performed to examine the expression levels of FGF-1 and FGF receptor 2 (FGFR2) in synovial and cartilage tissues. We detected FGF-1 in the synovial fluid from all eight donors, as well as in the culture medium of synovial fibroblasts. Synovial fluid from patients with OA and culture medium of OA synovial fibroblasts contained significantly more FGF-1 than those from controls. FGF-1 expression was also lower in the synovial membranes of normal donors than in those of OA patients. FGFR2 expression was also higher in OA cartilage than in normal cartilage. Overall, these results demonstrated that FGF-1 synthesis and secretion by synovial fibroblasts were significantly increased in OA. FGFR2 expression was also shown to be upregulated in patients with OA. These findings suggest that increased FGF-1 signaling correlates with an OA pathological condition.

Construction and expression of prokaryotic expression vectors fused with genes of Magnaporthe oryzae effector proteins and mCherry

The aim of the current study was to investigate the prokaryotic expression of the Magnaporthe oryzae effector genes BAS1 and BAS4 fused to the fluorescent protein mCherry. Based on previous polymorphic analysis of BAS1 and BAS4 in rice blast strains using PCR, blast strains containing the PCR products of BAS1 and BAS4 were selected for liquid culture for total RNA extraction. For PCR analysis, cDNA was selected as a template to amplify the coding region of BAS1 and BAS4, the plasmid pXY201 was selected as template to amplify the mCherry sequence, and the three sequences were cloned into pMD®19-T vectors. Positive recombinant plasmids were digested using two restriction enzymes and the cleaved fragments of BAS1 and mCherry and BAS4 and mCherry were ligated to pGEX-4T-1 vectors and expression was induced using IPTG. The PCR results showed that the sequence sizes of BAS1, BAS4, and mCherry were 348, 309, and 711 bp, respectively, and these were cloned into pMD®19-T vectors. After digestion and gel purification, the fragments of BAS1 and mCherry, BAS4 and mCherry were ligated into pGEX-4T-1 vectors and expressed in Escherichia coli BL21 competent cells. The expressed proteins were approximately 60 kDa, corresponding to their theoretical size. Prokaryotic expression products of BAS1 and BAS4 fused to mCherry were presented in this study, providing a base for constructing prokaryotic expression vectors of pathogen effector genes fused to mCherry, which will contribute to further study of the subcellular localization, function, and protein interactions of these effectors.

Communication: Tracking molecular structure deformation and relaxation in real time

The CH3I structural deformation induced by strong laser fields is revealed by time- and frequency-resolved ro-vibrational spectra. The experimental results show that the CH3I molecule undergoes ultrafast structural deformation of CH3 "umbrella-closing" induced by the strong fs laser field (more than 10(11) W/cm(2)) and followed by a structural relaxation of "umbrella-opening" within an exponential decay time scale of ∼620 fs. This study provides a first glimpse of the immense potential of the time- and frequency-resolved vibrational spectra in studying molecular deformation dynamics.

Construction of overexpression vectors of Magnaporthe oryzae genes BAS1 and BAS4 fusion to mCherry and screening of overexpression strains

The aim of this study was to construct overexpression vectors and selecting strains of the Magnaporthe oryzae effectors BAS1 and BAS4. Primer pairs of BAS1, BAS4, and mCherry were designed based on their known nucleotide sequences. The coding sequences of BAS1 and BAS4 were amplified, and the pXY201 plasmid was selected as a template to amplify the mCherry sequence. Fragments of BAS1 and mCherry, and BAS4 and mCherry were ligated into the pCAMBIA1302 vector. The recombinant pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry plasmids were transformed into E. coli DH5α competent cells. Transformants were screened by PCR, and plasmids from the positive transformants were extracted by enzymatic digestion to obtain pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry. The pCAMBIA-BAS1-mCherry and pCAMBIA-BAS4-mCherry plasmids were transformed into protoplasts of rice blast strains and the transformed strains were screened by PCR using primer pairs against the hygromycin gene. The result showed that the PCR products corresponded with the theoretical sizes. RT-PCR was used to analyze the expression of BAS1 and BAS4 in five transformed strains of BAS1 and BAS4, and the result showed that the higher expression level of the two genes was occurred in five transformant strains comparing to wild-type strain A3467-40 (the strain containing BAS1 and BAS4), but there was no difference among the five overexpression strains. The sporulation and spore germination of transformed strains was higher than in wild type strain, and there was no difference in the germination time. Construction of overexpression vectors and strains of M. oryzae effectors BAS1 and BAS4 provide reference material for other new effectors.

Effects of high-intensity treadmill training on timeliness and plasticity expression of irisin in mice

OBJECTIVE

The purpose of this study was to investigate effects of high-intensity aerobic exercise training on timeliness and plasticity expression of irisin in mice and change of FNDC5, ACCβ expression, and to explore possible ways to influence its mechanism of fatty acid metabolism.

MATERIALS AND METHODS

Adult male mice of specific pathogen-free grade [Kunming mice, (20 ± 2) g] are randomly divided into 4 groups. Wherein the first group is immediately after one-time exercise groups: including control group (CN group 1), 0.5 h exercise group (group 2), 1 h exercise group (group 3), 1.5 h exercise group (group 4) and 2 h exercise group (group 5), each for 10. The second group is rest after one-time 60 min exercise groups: including control group (CN group 1), rest 20 min groups (groups 2), rest 40 min group (group 3), rest 60 min group (groups 4), rest 80 min group (group 5), each for 10. Third group is immediately after long-term exercise groups: including the control group (CN group 1), 0.5 h exercise group (group 2), 1 h exercise group (group 3), 1.5 h exercise group (group 4) and 2 h exercise group (group 5), each for 10. The fourth group is rest after long-term 60 min exercise group: including control group (CN group 1), rest 20 min group (group 2), rest 40 min group (group 3), rest 60 min group (4 groups) and rest 80 min groups (5 groups), each for 10.

RESULTS

With the extension of a one-time high-intensity exercise time, the mouse FNDC5 protein, P-ACCβ / ACCβ ratio showed fluctuations, and opposite trends between the two, its turning points are 1.5 h; FNDC5 protein and P-ACCβ / ACCβ ratio with long-term exercise in mice at different time produce adaptability; the regulation of exercise induced irisin timeliness and plasticity reflected after a long-term exercise irisin expression in serum showed a steady decline in trend and return to normal levels, compared to a one-time exercise, expression of irisin is more stable.

CONCLUSIONS

With the high-intensity exercise a one-time extension of time, the mouse FNDC5 proteins, P-ACCβ / ACCβ ratio showed fluctuations, and both changes in the opposite trend, its turning points are 1.5 h; the long-term exercise can produce FNDC5 proteins, P-ACCβ / ACCβ ratios adaptable, more stable expression of the irisin curve after long-term exercise compared to a one-time exercise.

Influence of cyclophilin D protein expression level on endothelial cell oxidative damage resistance

We examined the influence of cyclophilin-D (CypD) protein expression level on endothelial cell oxidative damage resistance. A model of CypD protein expression or high expression in endothelial cells was established through gene silencing or cloning. The comparable groups were normal endothelial cells cultured in phosphate-buffered solution in liquid handling cells containing 500 mM H2O2 for 90 or 120 min, and then the medium was replaced with common nutrient solution and cultured again for 24 h. The apoptosis rate and nitric oxide (NO) levels of each group were tested. The cell apoptosis rate of the CyPD low expression group (32.51 ± 6.6 %) was significantly lower than that of the control group (52.57 ± 5.84%, P = 0.001), and total NO production was 24.06 ± 3 and 13.03 ± 3.55 μM. The apoptosis rate of the CyPD high expression group (24.24 + 3.08%) was significantly higher than that of the control group (7.7 + 0.68%, P < 0.001); total NO production was 3.55 ± 1.53 and 8.46 ± 0.77 μM, which was significantly different (P = 0.008). CypD protein could increase oxidative stress and cause endothelial cell injury and apoptosis.

Allergy to dust mites may contribute to early onset and severity of alopecia areata

BACKGROUND

A higher risk of allergic diseases such as rhinitis, asthma and atopic eczema (atopic dermatitis) has been reported for patients with alopecia areata (AA) compared with the general population, but the significance of this is still largely unclear.

AIM

To determine whether serum total or specific IgE play a role in the onset and severity of AA.

METHODS

We tested 461 serum samples from 351 patients with AA and 110 healthy controls (HC) for total IgE (tIgE) and specific IgE (sIgE) by ImmunoCAP-100 or in vitro test (IVT).

RESULTS

The absolute value of tIgE was higher in patients with AA than in normal controls (P < 0.001), although the prevalence of raised tIgE (> 120 IU/mL) detected in patients with AA (29.3%) was similar to that of HC (21.8%). Prevalences of raised sIgE against various allergens detected by ImmunoCAP-100 showed that Dermatophagoides pteronyssinus (Der p; 31.1%) and Dermatophagoides farinae (Der f; 29.0%) were the most common allergens. Similar results were found by IVT, with the most common response being against Der p/Der f (29.0%). However, the prevalences of tIgE and sIgE against dust mites (Der p and Der f) in patients with early-onset AA and severe AA were significantly higher than those with late-onset AA and mild AA (P = 0.02, P = 0.02 vs. P = 0.03 and P = 0.001, respectively). Notably, the increases in tIgE and sIgE were independent of atopy history.

CONCLUSIONS

Allergy to dust mites may have an effect on the immune response in AA, and may contribute to its early onset and severity in patients of Chinese origin.

Significant association of APOA5 and APOC3 gene polymorphisms with meat quality traits in Kele pigs

Apolipoprotein A5 (APOA5) and C3 (APOC3) genes are involved in the PPAR lipid metabolism pathway and thus associated with elevated triglyceride levels. However, whether APOA5 and APOC3 genetic polymorphisms affect intramuscular fat deposition and other meat quality traits remains unknown in pigs. One hundred and seventy-one Kele pigs were sampled to investigate genetic variants in the APOA5 and APOC3 genes and their association with seven pork quality traits. We identified 5 single nucleotide polymorphisms (SNPs) in the promoter region of the APOA5 gene and 17 SNPs in the APOC3 gene. Linkage disequilibrium analysis revealed 5 complete linkage disequilibria among these 22 SNPs. We found that 10 SNPs were significantly correlated with meat quality traits, including the mutation A5/-769 in the APOA5 gene, which was significantly associated with cooked weight percentage, and 9 SNPs in the APOC3 gene that were significantly associated with drip loss rate, meat color value of longissimus dorsi muscle and shear force. Therefore, these SNP markers will be useful for marker-assisted selection for improved pork quality.

hCLCA1 DNA vaccine suppresses cell hyperplasia and mucin expression of goblet cells in vitro

BACKGROUND

Excessive airway mucus secretion is a remarkable trait of asthma. Mucus overproduction mainly resulted from an increase in goblet cell numbers, which causes considerable damage to health. However, effective therapeutic treatments are still lacking for mucus hypersecretion. Human calcium-activated chloride channel 1 (hCLCA1) has been identified to be predominantly responsible for mucus hypersecretion.

OBJECTIVES

In this study, we investigated the effects of an hCLCA1 DNA vaccine on the control of mucus production and goblet cell proliferation using an in vitro model goblet cell line (NCI-H292).

METHODS

The effect of the hCLCA1 DNA vaccine on cell viability and proliferative activity of NCI-H292/hCLCA1 was analyzed by electron microscopy, MTT assay, and flow cytometry. Expression of mucins and MUC5AC, a major member of the mucin gene family in airway goblet cells, was assessed under hCLCA1 DNA vaccine challenges by periodic acid-Schiff staining, quantitative real-time PCR and Western blot, respectively, and the expression profile of granulocyte-macrophage colony-stimulating factor (GM-CSF), a critical cytokine in airway inflammation, was also examined by real-time PCR and immunocytochemistry.

RESULTS

Results showed that hCLCA1 overexpression caused high cell proliferation and mucin expression, whereas the hCLCA1 DNA vaccine could effectively reverse these abnormal effects. In addition, GM-CSF expression was highly induced by hCLCA1 overexpression and efficiently suppressed by hCLCA1 DNA vaccine.

CONCLUSIONS

These results illustrate that the hCLCA1 DNA vaccine effectively inhibits cell hyperplasia and mucin gene expression of goblet cells, suggesting that the hCLCA1 DNA vaccine has potential value in the treatment of human asthma.

Elicitation and in situ adsorption enhanced secondary metabolites production of Tripterygium wilfordii Hook. f. adventitious root fragment liquid cultures in shake flask and a modified bubble column bioreactor

The experiments of elicitation and in situ adsorption were conducted in shake flasks and then tested in a modified bubble column bioreactor for enhancing the productions of three active metabolites in Tripterygium wilfordii Hook. f., triptolide, wilforgine and wilforine. Methyl jasmonate was screened out as the elicitor and the non-ionic polymeric ion-exchange resin of Amberlite(®) XAD-7 was used for in situ product removal and protecting the alkaloids from degradation in the medium. In shake flask experiments, 3.55-fold, 49.11-fold, and 10.40-fold of triptolide, wilforgine, and wilforine, respectively, could be recovered from the medium and XAD-7 resin by elicitation and in situ product removal, compared with the control. The modified 10 L bubble column bioreactor had similar productions of the three active metabolites but needed a further optimization of parameters for better growth of adventitious roots.

Effects of preventive acupuncture on streptozotocin-induced hyperglycemia in rats

BACKGROUND

Diabetes prevention has received increasing attention recently. Clinical and experimental studies showed that acupuncture could produce hypoglycemic effect. However, little is known about the effectiveness of acupuncture in diabetes prevention.

AIM

To investigate the preventive effects of acupuncture on streptozotocin (STZ)-induced hyperglycemia in rats.

METHODS

Hyperglycemia was induced by a single intraperitoneal injection of STZ (60 mg/kg). Rats were randomly divided into six groups (no.=8 each group): control, diabetes, preventive acupuncture plus STZ injection, STZ injection plus therapeutic acupuncture, STZ injection plus preventive and therapeutic acupuncture, and preventive and therapeutic acupuncture control. Body weight, blood glucose, serum insulin, lipid peroxidation, and antioxidant enzymes were measured by routine standard methods. Histological analysis of pancreatic islets was conducted.

RESULTS

Preventive acupuncture significantly relieved hyperglycemia, insulin deficiency, weight loss, and pancreatic islet damage in rats with STZ injection; it also significantly reduced serum lipid peroxidation and enhanced superoxide dismutase in the serum and the pancreas without significantly affecting serum glutathione peroxidase and catalase. Therapeutic acupuncture exhibited a hypoglycemic effect in the late stage, but did not significantly improve other parameters.

CONCLUSIONS

These results indicate that preventive acupuncture is beneficial to the control of STZ-induced hyperglycemia in rats.

Human papilloma virus screening by hybrid capture II in Chinese women of Jiangsu Province

OBJECTIVE

To survey Human Papilloma Virus (HPV) infection in Chinese Women of Jiangsu Province and discuss the relationship between HPV and the biology of cervical cancer.

METHODS

Two thousand, one hundred and fifty-three sexually active women (including 66 cases of cervical cancer) were selected for high-risk human papilloma virus DNA test with Hybrid Capture II (HCII).

RESULTS

The overall HPV prevalence was 32.6% (701/2153) with higher positive rates in cervical carcinoma and Cervical Interstitial Neoplasia (CIN) [93.9% and 54.6%] respectively. For women aged 40-59 years, the overall high-risk HPV prevalence was higher than those of other age groups. Compared with CIN I, the positivity rate and viral load of HPV DNA in CIN III is much higher (80.2% vs. 29.9%, 11.89 vs. 0.53). Ninety-four per cent (64/66) of patients with Cervical cancer were detected to be HPV positive. There was no significant difference in HPV DNA among each clinical stage and pathologic grade. But the positive rates and the value of HPV DNA were higher in the patients with cervical interstitial incursion. Eighty per cent of patients (20/25) could become negative within six months after operation.

CONCLUSIONS

High-risk HPV DNA test is effective in screening for cervical diseases. HCII is an effective method to detect HPV DNA.

Enhanced fluorescence from CdTe quantum dots self-assembled on the surface of silver nanoparticles

This paper presents an investigation on the fluorescent properties of semiconductor CdTe quantum dots (QDs) self-assembled on the surface of PVP (polyvinylpyrrolidone)-capped silver nanoparticles (NPs) by the ligand field effect. A significant 2.5-fold enhancement in the integrated fluorescence intensities, red shift of fluorescence peak, and obvious decrease of lifetime were observed in the CdTe QDs assembled on the Ag NPs in comparison with the pure CdTe QDs. The fluorescence enhancement factor and red shift were found to depend on the Ag NP concentration. The fluorescence enhancement was attributed to a highly localized electromagnetic field on the Ag NPs generated by the surface plasma and the change in the surface trap state of the CdTe QDs originating from plasma oscillations in the Ag NPs. It is first proposed that the surface passivation of CdTe QDs is also an important factor for metal-enhanced fluorescence. The surface defects of CdTe QDs can be modified by the Cd-O coordination interaction between the CdTe QDs and PVP molecules, which will cause the trap state density and luminescence lifetime to decrease. The surface passivation of CdTe QDs can also improve fluorescence quantum yield and lead to the red shift of the fluorescence peak. Compared with previous reports, the occurrence of the self-assembly of CdTe QDs on the surface of PVP-capped Ag NPs is fairly simple and easy. From a practical point of view, the combination of CdTe QDs with Ag NPs may lead to the fluorescence enhancement, which could be utilized in a variety of chemical and biological detection applications.

A clinical study of 115 patients with extranodal natural killer/T-cell lymphoma, nasal type

AIMS

To investigate the clinicopathological features, treatment outcomes, and prognostic factors in patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 115 patients diagnosed with extranodal NK/T-cell lymphoma, nasal type who were admitted to our hospital between January 1991 and June 2006.

RESULTS

In total, 107 patients were available for follow-up. After the completion of treatment, 48 patients (44.9%) achieved a complete remission. By the end of the follow-up period, 60 patients (56.1%) had died from local recurrence or metastases. The mean survival duration was 70.0 months, the median survival duration was 42 months, and the 5-year survival rate was 39.4%. The mean survival durations of the three treatment groups of chemoradiotherapy, radiotherapy and palliative treatment were 91.6, 60.1 and 17.6 months, respectively. The median survival durations were 72.0, 42.0 and 10 months, respectively. Patients treated with > 50 Gy had better local control and survival than the < 50 Gy group. However, there was no significant difference between patients having fewer than four cycles of chemotherapy and patients having more than four cycles. Multifactor Cox regression model analysis showed that B symptoms, gender, International Prognostic Index (IPI) score, disease stage and therapy were all independent prognostic factors.

CONCLUSIONS

The prognosis of extranodal NK/T-cell lymphoma, nasal type is poor and significantly influenced by B symptoms, gender, IPI score, clinical staging and the method of treatment. Chemoradiotherapy should be the first choice for treatment.

A widely tunable dual-wavelength CW Ti:sapphire laser with collinear output

We report a collinear output and tunable dual-wavelength CW Ti:sapphire laser with a simple cavity configuration. The wavelength splitting range is easily tuned from 10 nm to 110 nm, which provides 56 THz bandwidth for terahertz generation. The total output power of two colors with the spatial mode of TEM(00) is between 700 mW and 300 mW, for small and large wavelength splittings, respectively, under 5 W argon-ion laser pumping.

Upconversion luminescence of CdTe nanocrystals by use of near-infrared femtosecond laser excitation

We study the steady-state and time-resolved luminescent properties of CdTe nanocrystals by one- and two-photon excitation with a femtosecond laser. We observe that 1208 nm excitation causes a shift of the emission peak of about 20 nm to the infrared compared with 400 nm laser excitation. It is found that upconversion luminescence is composed of a photoinduced trapping and a band edge excitonic state and produces the observation of biexponential decay kinetics. We conclude that the redshift of the emission peak is caused by the relative change in luminescence intensity between excitonic and trapping states.

Human periodontal ligament cells express osteoblastic phenotypes under intermittent force loading in vitro

Mechanical strain applied to bone leads to bone remodeling. In the oral cavity, it is unclear how such mechanical force applied to move teeth orthodontically induces alveolar bone remodeling. It is known that osteoclasts are the only cells that are responsible for bone resorption, while the formation and activity of osteoclasts are regulated by osteoblasts. So it is believed that osteoblasts play an important role not only in bone formation but in bone remodeling as well. Therefore, the purpose of this study was to examine the effect of mechanical force on human periodontal ligament (PDL) cells and whether they express osteoblastic characters in vitro.

METHODS

Human PDL cells cultured in vitro were loaded with intermittently stretching force for 24 hours. The expression of alkaline phosphatase (ALP), osteocalcin (OCN) and osteoprotegerin (OPG) were detected at mRNA and protein levels at 0, 2nd, 4th, 6th, 12th, 24th hours after intermittent force loading.

RESULTS

Without any stimulation, ALP and OPG mRNA expressions were detected in human PDL cells by in-situ hybridization, but not that of OCN mRNA. ALP mRNA signal was up-regulated and that of OPG was down-regulated by mechanical force within 24 hours. OCN mRNA expression was induced by mechanical force in the late phase of the 24-hours loading cycle. The changes in secreted proteins showed similar results with those seen at the mRNA level.

CONCLUSION

Human PDL cells express osteoblastic phenotypes under intermittent force loading and play a role in alveolar bone remodeling.

The expression of osteoprotegerin and the receptor activator of nuclear factor kappa B ligand in human periodontal ligament cells cultured with and without 1α,25-dihydroxyvitamin D3

The receptor activator of nuclear factor kappa B ligand (RANKL) and its decoy receptor, osteoprotegerin (OPG), are important bone metabolism molecules, which directly control osteoclastogenesis. Periodontal ligament (PDL) cells play a vital role in maintaining the homeostasis of periodontal tissues, releasing cytokines to affect bone metabolism. The purpose of this study was to investigate the expression of OPG and RANKL in cultured human periodontal ligament cells (hPDLCs) derived from permanent teeth and the expression change after stimulation by 1alpha,25-dihydroxyvitamin D(3) (1alpha,25(OH)(2)vitD(3)), a kind of bone resorption promoter. HPDLCs were cultured in the presence or absence of 10(-8)M 1alpha,25(OH)(2)vitD(3) in vitro. The expression of mRNA for OPG and RANKL in hPDLCs during 6 days' culture was examined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The level of secreted OPG protein in the culture medium during 6 days' culture was detected by enzyme-linked immunoabsorbent assay (ELISA). The result showed that OPG and RANKL were expressed by hPDLCs. OPG expression was down-regulated by 10(-8)M 1alpha,25(OH)(2)vitD(3) in a time-dependent manner, while RANKL mRNA was up-regulated. The ratio of OPG/RANKL was decreased. In conclusion, our findings suggest that hPDLCs may regulate the alveolar bone metabolism through the OPG/RANKL system.