RNF43 Inactivation Enhances the B-RAF/MEK Signaling and Creates a Combinatory Therapeutic Target in Cancer Cells

RING finger 43 (RNF43), a RING-type E3 ubiquitin ligase, is a key regulator of WNT signaling and is mutated in 6-10% of pancreatic tumors. However, RNF43-mediated effects remain unclear, as only a few in vivo substrates of RNF43 are identified. Here, it is found that RNF43-mutated pancreatic cancer cells exhibit elevated B-RAF/MEK activity and are highly sensitive to MEK inhibitors. The depletion of RNF43 in normal pancreatic ductal cells also enhances MEK activation, suggesting that it is a physiologically regulated process. It is confirmed that RNF43 ubiquitinates B-RAF at K499 to promote proteasome-dependent degradation, resulting in reduced MEK activity and proliferative ability in cancer cells. In addition, phosphorylation of B-RAF at T491 suppresses B-RAF ubiquitination by decreasing the interaction between RNF43 and B-RAF. Mutations at K499 in B-RAF are identified in various cancer types. MEK and WNT inhibitors synergistically suppress the growth of RNF43-mutated pancreatic cancer cells in vitro and in vivo. Collectively, the research reveals a novel mechanism by which RNF43 inhibits B-RAF/MEK signaling to suppress tumor growth and provide a new strategy for the treatment of RNF43-inactivated pancreatic cancer.

[The association between body mass index and in-hospital major adverse cardiovascular and cerebral events in patients with acute coronary syndrome]

Objective: To assess the association between body mass index (BMI) and major adverse cardiovascular and cerebrovascular events (MACCE) among patients with acute coronary syndrome (ACS). Methods: This was a multicenter prospective cohort study, which was based on the Improving Care for Cardiovascular Disease in China (CCC) project. The hospitalized patients with ACS aged between 18 and 80 years, registered in CCC project from November 1, 2014 to December 31, 2019 were included. The included patients were categorized into four groups based on their BMI at the time of admission: underweight (BMI<18.5 kg/m2), normal weight (BMI between 18.5 and 24.9 kg/m2), overweight (BMI between 25.0 and 29.9 kg/m2), and obese (BMI≥30.0 kg/m2). Multivariate logistic regression models was used to analyze the relationship between BMI and the risk of in-hospital MACCE. Results: A total of 71 681 ACS inpatients were included in the study. The age was (63.4±14.7) years, and 26.5% (18 979/71 681) were female. And the incidence of MACCE for the underweight, normal weight, overweight, and obese groups were 14.9% (322/2 154), 9.5% (3 997/41 960), 7.9% (1 908/24 140) and 7.0% (240/3 427), respectively (P<0.001). Multivariate logistic regression analysis showed a higher incidence of MACCE in the underweight group compared to the normal weight group (OR=1.30, 95%CI 1.13-1.49, P<0.001), while the overweight and obese groups exhibited no statistically significant difference in the incidence of MACCE compared to the normal weight group (both P>0.05). Conclusion: ACS patients with BMI below normal have a higher risk of in-hospital MACCE, suggesting that BMI may be an indicator for evaluating short-term prognosis in ACS patients.

[Construction of natural population cohort on telephone follow-up management quality control system and discussion regarding critical issues by REDCap system]

With completing a baseline survey of a large natural population cohort, conducting regular follow-up has become a key factor in further improving the quality of cohort construction and ensuring its sustainable development. Typical cohort follow-up methods include repeat surveys, routine monitoring, and community-oriented surveillance. However, in practical applications, there are often issues such as high costs, difficulty, and high error rates. Telephone follow-up is an important supplementary method to the methods mentioned above, as it has the characteristics of low cost, fast response, and high quality. However, the with difficult organization, quality control is challenging, response rates are low, and management levels vary widely, which limits its widespread use in large-scale population cohort studies. Given the above problems, this study draws on customer relationship management based on the actual needs of the China Northwest Cohort follow-up. It relies on the REDCap electronic data collection platform to build a telephone follow-up management and quality control system. Targeted solutions are provided for key issues in telephone follow-up implementation, including organizational structure, project management, data collection, and process quality control, to improve the quality control level of telephone follow-up comprehensively and thereby enhance the quality and efficiency of follow-up. We hope to provide standardized follow-up programs and efficient quality control tools for newly established and existing cohort studies.

A Low-Cost, Sensitive Reporter System Using Membrane-Tethered Horseradish Peroxidase for Efficient Gene Expression Analysis

Reporter gene assays are essential for high-throughput analysis, such as drug screening or determining downstream signaling activation/inhibition. However, use of this technology has been hampered by the high cost of the substrate (e.g., d-Luciferin (d-Luc)) in the most common firefly luciferase (FLuc) reporter gene assay. Although alternate luciferase is available worldwide, its substrate has remained expensive, and a more affordable option is still in demand. Here, we present a membrane-tethered horseradish peroxidase (mHRP), a new reporter system composed of a cell membrane expressing HRP that can preserve its enzymatic function on the cell surface, facilitates contact with HRP substrates (e.g., ABTS and TMB), and avoids the cell lysis process and the use of the high-priced luciferase substrate. An evaluation of the light signal sensitivity of mHRP compared to FLuc showed that both had comparable signal sensitivity. We also identified an extended substrate half-life of more than 5-fold that of d-Luc. Of note, this strategy provided a more stable detection signal, and the cell lysis process is not mandatory. Furthermore, with this strategy, we decreased the total amount of time taken for analysis and increased the time of detection limit of the reporter assay. Pricing analysis showed a one-third to one twenty-eighth price drop per single test of reporter assay. Given the convenience and stability of the mHRP reporter system, we believe that our strategy is suitable for use as an alternative to the luciferase reporter assay.

[Spatial-temporal characteristics and influencing factors of pulmonary tuberculosis cases in Shanghai from 2013 to 2020]

Objective: To use the spatiotemporal distribution model and INLA algorithm to study the spatiotemporal characteristics and influencing factors of tuberculosis in Shanghai and to provide a theoretical basis for formulating regional tuberculosis epidemic prevention and control measures. Methods: Based on the data of registered pulmonary tuberculosis cases in Shanghai during 2013-2020 derived from the tuberculosis management information system of China Disease Control and Prevention Information System, the hierarchical Bayesian model was adopted to fit the tuberculosis case data, identify the spatiotemporal variation characteristics of tuberculosis, and explore the potential socioeconomic characteristics and other factors related to health services and spatiotemporal characteristics. Results: From 2013 to 2020, 29 281 registered tuberculosis cases were reported in Shanghai, with an average annual incidence of 25.224/100 000. From 2013 to 2020, the incidence trend increased first and then decreased, the highest incidence was reported in 2014 (27.991/100 000). The incidence of tuberculosis in Shanghai is characterized by spatial clustering. Through the spatial characteristics and risk analysis of the reported incidence of tuberculosis, it is found that the high-risk area of tuberculosis in Shanghai is the suburban communities, whereas downtown communities are the low-risk areas. The incidence risk of pulmonary tuberculosis is associated with the gross domestic product per capita (RR=0.48), the number of beds per 10 000 persons (RR=0.56), the normalized vegetation index (RR=0.50), and the night light index (RR=0.80). Conclusions: With the steady progress of tuberculosis prevention and control in the central urban area of Shanghai, special attention should be paid to the prevention and control in the suburbs further to improve the social and economic level in the suburbs and increase the coverage rate of urban green space, to reduce the incidence of tuberculosis and reduce the disease burden of tuberculosis in Shanghai.

[Incremental value of epicardial fat volume on predicting obstructive coronary artery disease with myocardial ischemia]

Objective: This study aimed to investigate the association between epicardial fat volume (EFV) and obstructive coronary artery disease (CAD) with myocardial ischemia, and evaluate the incremental value of EFV on top of traditional risk factors and coronary artery calcium (CAC) in predicting obstructive CAD with myocardial ischemia. Methods: This study was a retrospective cross-sectional study. Patients with suspected CAD who underwent coronary angiography (CAG) and single photon emission computerized tomography-myocardial perfusion imaging (SPECT-MPI) at the Third Affiliated Hospital of Soochow University from March 2018 to November 2019 were consecutively enrolled. EFV and CAC were measured by non-contrast chest computed tomography (CT) scan. Obstructive CAD was defined as coronary artery stenosis≥50% in at least one of the major epicardial coronary arteries, and myocardial ischemia was defined as reversible perfusion defects in stress and rest MPI. Obstructive CAD with myocardial ischemia was defined in patients with coronary stenosis severity≥50% and reversible perfusion defects in the corresponding areas of SPECT-MPI. Patients with myocardial ischemia bot without obstructive CAD were defined as none-obstructive CAD with myocardial ischemia group. We collected and compared the general clinical data, CAC and EFV between the two groups. Multivariable logistic regression analysis was performed to identify the relationship between EFV and obstructive CAD with myocardial ischemia. ROC curves were performed to determine whether addition of EFV improved predictive value beyond traditional risk factors and CAC for obstructive CAD with myocardial ischemia. Results: Among the 164 patients with suspected CAD, 111 patients were males, and average age was (61.4±9.9) years old. 62 (37.8%) patients were included into the obstructive CAD with myocardial ischemia group. 102 (62.2%) patients were included into the none-obstructive CAD with myocardial ischemia group. EFV was significantly higher in obstructive CAD with myocardial ischemia group than in none-obstructive CAD with myocardial ischemia group ((135.63±33.29)cm³ and (105.18±31.16)cm³, P<0.01). Univariate regression analysis showed the risk of obstructive CAD with myocardial ischemia increased by 1.96 times for each SD increase in EFV(OR 2.96; 95%CI, 1.89-4.62; P<0.01). After adjustment for traditional risk factors and CAC, EFV remained as an independent predictor for obstructive CAD with myocardial ischemia (OR, 4.48, 95%CI, 2.17-9.23; P<0.01). Addition of EFV to CAC and traditional risk factors was related to larger AUC for predicting obstructive CAD with myocardial ischemia (0.90 vs. 0.85, P=0.04, 95%CI: 0.85-0.95) and the global chi-square increased by 21.81 (P<0.05). Conclusions: EFV is an independent predictor for obstructive CAD with myocardial ischemia. Addition of EFV to traditional risk factors and CAC has incremental value for predicting obstructive CAD with myocardial ischemia in this patient cohort.

[Comparison of the predictive value of Padua and the IMPEDE assessment scores for venous thromboembolism in patients with newly diagnosed multiple myeloma: A single institution experience]

Objective: To compare the predictive efficacy of the two thrombosis risk assessment scores (Padua and IMPEDE scores) in venous thromboembolism (VTE) within 6 months in patients with newly diagnosed multiple myeloma (NDMM) in China. Methods: This study reviewed the clinical data of 421 patients with NDMM hospitalized in Beijing Jishuitan Hospital from April 2014 to February 2022. The sensitivity, specificity, accuracy, and Youden index of the two scores were calculated to quantify the thrombus risk assessment of VTE by the Padua and IMPEDE scores. The receiver operating characteristics curves of the two evaluation scores were drawn. Results: The incidence of VTE was 14.73%. The sensitivity, specificity, accuracy, and Youden index of the Padua score were 100%, 0%, 14.7%, and 0% and that of the IMPEDE score was 79%, 44%, 49.2%, and 23%, respectively. The areas under the curve of Padua and IMPEDE risk assessment scores were 0.591 and 0.722, respectively. Conclusion: IMPEDE score is suitable for predicting VTE within 6 months in patients with NDMM.

Effects of Coated Sodium Butyrate on Growth Performance, Intestinal Morphology, and Caecal Short-chain Fatty Acids of Growing Pekin Ducks

1. A dose‒response experiment with six supplemental levels of coated sodium butyrate (CSB) (0, 250, 500, 750, 1,000, and 1,250 mg/kg) was conducted to investigate its effects on growth performance, intestinal morphology, and caecal short-chain fatty acids of growing Pekin ducks aged 14 to 35 d. A total of 288 male 14-d-old Pekin ducks were randomly allocated to six dietary treatments. Each treatment had eight replicate pens of six ducks per pen.2. The daily weight gain, daily feed intake, and feed/gain of ducks from 14 to 35 d of age were not influenced by increasing CSB levels. The relative weight and length of the duodenum, jejunum, and cecum increased linearly or quadratically as supplemental CSB increased (P<0.05).3. For the ileum and caecum, the villus height and height/crypt depth increased linearly or quadratically, and the villus crypt depth decreased linearly as the supplemental CSB increased (P<0.05). As supplemental CSB increased, the goblet cell numbers of the ileum increased and decreased and changed quadratically (P<0.05), but caecal goblet cell number increased quadratically (P<0.05). Increasing the CSB level linearly or quadratically elevated the concentrations of acetic acid, propionic acid, and butyric acid in the cecum (P<0.05).4. It was concluded that CSB can be used as a safe and effective feed additive to promote the intestinal integrity of growing ducks by improving intestinal morphology and increasing the concentration of caecal short-chain fatty acids.

[A descriptive analysis on hypertension in adult twins in China]

Objective: To describe the distribution characteristics of hypertension among adult twins in the Chinese National Twin Registry (CNTR) and to provide clues for exploring the role of genetic and environmental factors on hypertension. Methods: A total of 69 220 (34 610 pairs) of twins aged 18 and above with hypertension information were selected from CNTR registered from 2010 to 2018. Random effect models were used to describe the population and regional distribution of hypertension in twins. To estimate the heritability, the concordance rates of hypertension were calculated and compared between monozygotic twins (MZ) and dizygotic twins (DZ). Results: The age of all participants was (34.1±12.4) years. The overall self-reported prevalence of hypertension was 3.8%(2 610/69 220). Twin pairs who were older, living in urban areas, married, overweight or obese, current smokers or ex-smokers, and current drinkers or abstainers had a higher self-reported prevalence of hypertension (P<0.05). Analysis within the same-sex twin pairs found that the concordance rate of hypertension was 43.2% in MZ and 27.0% in DZ, and the difference was statistically significant (P<0.001). The heritability of hypertension was 22.1% (95%CI: 16.3%- 28.0%). Stratified by gender, age, and region, the concordance rate of hypertension in MZ was still higher than that in DZ. The heritability of hypertension was higher in female participants. Conclusions: There were differences in the distribution of hypertension among twins with different demographic and regional characteristics. It is indicated that genetic factors play a crucial role in hypertension in different genders, ages, and regions, while the magnitude of genetic effects may vary.

[Outcomes of fluoroscopy-free hip arthroscopy technique in the treatment of femoroacetabular impingement syndrome]

Objective: To evaluate the effect of fluoroscopy-free technique in the arthroscopic treatment of femoroacetabular impingement syndrome (FAIS). Methods: A retrospective cohort study. Clinical data of FAI patients treated with hip arthroscopy in the No.4 Medical Center, PLA General Hospital from October 2018 to December 2021 were retrospectively analyzed. The patients were divided into two groups according to the surgical procedure: the fluoroscopy group and the fluoroscopy-free group. The operation time and modified Harris hip score (mHHS), international hip outcome tool (iHOT12) and visual analogue scale (VAS) of hip joint pain before and after the operation were observed and compared between the two groups. And the incidence of surgical complications in the two groups were compared too. Results: A total of 460 patients (213 males and 247 females) [aged (32.6±8.3) years (15-67 years)] with valid follow-up were included in this study. There were 275 cases in the fluoroscopy-free group and 185 cases in the fluoroscopy group. The operation time was shorter in the fluoroscopy-free group when compared with that in the fluoroscopy group, and the difference was statistically significant [(93.36±12.54) min vs (115.62±6.03) min, P<0.001]. In both groups, the VAS scores decreased and the mHHS scores and iHOT12 scores improved significantly at the last follow-up when compared with those before the operation (all P<0.001); however, there was no significant difference in the scores between the two groups (all P>0.05). The complication rate in the fluoroscopy-free group was 10.18% (28/275), and it was 10.81%(20/185) in the fluoroscopy group (P=0.829). Conclusion: Fluoroscopy-free hip arthroscopy technique for FAI can avoid radiation and shorten the operation time, but it does not increase the incidence of complications with reliable clinical outcomes.

[Exosomes secreted from human umbilical cord mesenchymal stem cells promote pancreatic ductal adenocarcinoma growth by transferring miRNAs]

Objective: To observe the effects of exosomes derived from human umbilical cord mesenchymal stem cells on the proliferation and invasion of pancreatic cancer cells, and to analyze the contents of exosomes and explore the mechanisms affecting pancreatic cancer cells. Methods: Exosomes extracted from human umbilical cord mesenchymal stem cells were added to pancreatic cancer cells BxPC3, Panc-1 and mouse models of pancreatic cancer, respectively. The proliferative activity and invasion abilities of BxPC3 and Panc-1 cells were measured by cell counting kit-8 (CCK-8) and Transwell assays. The expressions of miRNAs in exosomes were detected by high-throughput sequencing. GO and KEGG were used to analyze the related functions and the main metabolic pathways of target genes with high expressions of miRNAs. Results: The results of CCK-8 cell proliferation assay showed that the absorbance of BxPC3 and Panc-1 cells in the hucMSCs-exo group was significantly higher than that in the control group [(4.68±0.09) vs. (3.68±0.01), P<0.05; (5.20±0.20) vs. (3.45±0.17), P<0.05]. Transwell test results showed that the number of invasion cells of BxPC3 and Panc-1 in hucMSCs-exo group was significantly higher than that in the control group (129.40±6.02) vs. (89.40±4.39), P<0.05; (134.40±7.02) vs. (97.00±6.08), P<0.05. In vivo experimental results showed that the tumor volume and weight in the exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exo) group were significantly greater than that in the control group [(884.57±59.70) mm(3) vs. (695.09±57.81) mm(3), P<0.05; (0.94±0.21) g vs. (0.60±0.13) g, P<0.05]. High-throughput sequencing results showed that miR-148a-3p, miR-100-5p, miR-143-3p, miR-21-5p and miR-92a-3p were highly expressed. GO and KEGG analysis showed that the target genes of these miRNAs were mainly involved in the regulation of glucosaldehylation, and the main metabolic pathways were ascorbic acid and aldehyde acid metabolism, which were closely related to the development of pancreatic cancer. Conclusion: Exosomes derived from human umbilical cord mesenchymal stem cells can promote the growth of pancreatic cancer cells and the mechanism is related to miRNAs that are highly expressed in exosomes.

[Effect of "one-stop" outpatient management on the control rate of multiple metabolic disorders patients]

Objective: To explore the effect of "one-stop" outpatient management on the therapeutic schedule and control rate of patients with metabolic disorders. Methods: A total of 332 patients who met the inclusion criteria were enrolled and treated regularly in the "one-stop" outpatient department of the Department of Cardiology of the Third Hospital of Peking University from November 1, 2020 to April 30, 2022. The general information, personal history, family history, drug treatment plan, blood pressure, height, weight, waist circumference, and hip circumference of patients were collected through the outpatient electronic medical record system, and patients were followed up through conducting "one-stop" comprehensive management. The baseline clinical characteristics were analyzed, and the changes of metabolic indexes, treatment conditions and control rate of patients with different metabolic disorders before and after the "one-stop" outpatient management were compared. Results: The time interval between the first visit and the last visit was 44 (26, 60) weeks in 332 patients, whose age was (57.2±13.2) years, including 219 males (66.0%). After the "one-stop" outpatient management, fasting blood glucose (FBG) [ 6.6 (5.6, 7.9) mmol/L vs 6.3 (5.6, 6.9) mmol/L], glycosylated hemoglobin A1c (HbA1c) [ (7.2±1.5) % vs (6.6±0.8) %], low density lipoprotein cholesterol (LDL-C) [ 2.70 (1.97, 3.55) mmol/L vs 2.04 (1.66, 2.63) mmol/L] and blood uric acid (UA) [ (383.7±107.1) μmol/L vs (341.2±90.6) μmol/L] all decreased significantly (all P values<0.05). The control rates of hypertension (19.8% vs 28.2%), diabetes (45.2% vs 66.5%), hyperlipidemia (54.9% vs 87.6%) and hyperuricemia (16.7% vs 49.0%) were significantly improved after the "one-stop" outpatient management (all P values<0.05). Conclusion: The "one-stop" outpatient management of cardiovascular department can significantly improve the metabolic condition and the control rate of patients with multiple metabolic disorders.

[Impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease]

Objective: This study sought to investigate the impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease. Methods: We retrospectively analyzed clinical data of male patients diagnosed with suspected coronary microvascular dysfunction (CMD) in the First Hospital of Shanxi Medical University between December 2015 and August 2021. All patients underwent the one-day rest and stress ¹³N-ammonia positron emission tomography myocardial perfusion imaging. Overall obesity was defined by body mass index (BMI) ≥28 kg/m² and abdominal obesity was defined by waist circumference ≥90 cm. Hyperemic myocardial blood flow (MBF)<2.3 ml·min^-1·g^-1 or coronary flow reserve (CFR)<2.5 were referred as CMD. All patients were grouped based on their BMI and waist circumference. MBF, CFR, the incidence of CMD, hemodynamic parameters, and cardiac function were compared among the groups. Results: A total of 136 patients were included. According to BMI and waist circumference, patients were categorized into 3 groups: control group (n=45), simple abdominal obesity group (n=53) and compound obesity group (n=38). Resting MBF did not differ between groups (F=0.02,P=0.994). Compared with the control group, hyperemic MBF was significantly lower in the simple abdominal obesity and compound obesity groups ((2.82±0.64) ml·min^-1·g^-1, (2.44±0.85) ml·min^-1·g^-1 and (2.49±0.71) ml·min^-1·g^-1, both P<0.05, respectively). Hyperemic MBF was comparable among the groups of patients with obesity (P=0.772). CFR was significantly lower in the simle abdominal obesity group compared with the control group (2.87±0.99 vs. 3.32±0.62,P=0.012). Compared with the control group, CFR tended to be lower in the compound obesity group (3.02±0.91 vs. 3.32±0.62,P=0.117). The incidence of CMD was significantly higher in both the simple abdominal obesity and compound obesity groups than in the control group (62.3%, 52.6% vs. 22.2%, both P<0.01, respectively). Waist circumference was an independent risk factor for male CMD (OR=1.057, 95%CI: 1.013-1.103, P=0.011). Conclusions: In male patients with non-obstructive coronary artery disease, abdominal obesity is associated with decreased coronary microvascular function. Male patients with simple abdominal obesity face the highest risk of CMD.

[Application of isotemporal substitution model in epidemiological research]

Isotemporal substitution model is a powerful tool to explore the real association between physical behavior and health outcomes, which has the potential of the application in large-scale cohort study. This paper systematically introduces the principle of isotemporal substitution model and its implementation method in specific analysis to provide analytical ideas for the epidemiological research related to physical behavior in China. The baseline data of Regional Ethic Cohort Study in Northwest China conducted in Shaanxi province were used to analyze the relationship between physical behavior and cardiovascular disease with single-factor model, partition model and isotemporal substitution model. The advantages and disadvantages of different models were compared, and the advantages of isotemporal substitution model in quantifying physical activity health risk were introduced. Isotemporal substitution model could qualify physical behavior and health outcomes, which has wide application value in epidemiological research.

[Spatiotemporal characteristics of hand,foot and mouth disease and influencing factors in China from 2011 to 2018]

Objective: To analyze the spatiotemporal characteristics of hand,foot and mouth disease (HFMD) in China, explore the association of socioeconomic, population and health services factors with the incidence of HFMD in China, and provide information for the prevention and control of HFMD. Methods: Bayesian spatiotemporal model was used to fit the data of HFMD, evaluate the spatiotemporal variation of HFMD, and identify the potential association between the risk of HFMD and social, economic, population and health services. Results: From 2011 to 2018, a total of 17 118 050 HFMD cases, including 2 283 deaths, were reported in China. The reported incidence showed a fluctuating increase trend from 2011 to 2014, and a fluctuating decrease trend from 2014 to 2018. Meanwhile, there was a fluctuating decrease trend of mortality rate. The incidence of HFMD had spatial clustering, with the highest incidence in southern China with hot spot and high risk areas, and the lowest incidence in northwestern China where cold spot and low risk areas were found. The risk for HFMD was associated with GDP per capita (RR=3.54), number of industrial enterprises above designated size of 10 000 people (RR=1.61), urbanization rate (RR=3.00), birth rate (RR=2.36), number of beds in medical institutions per 10 000 people (RR=3.40), and green area in parks per capita (RR=0.57). Conclusions: The hotspot area for HFMD prevention and control in China was in the southeast coastal provinces from 2011 to 2018. In order to reduce the incidence of HFMD, it is necessary to increase the green area in parks per capita while accelerating urbanization process.

Structural insights into Nirmatrelvir (PF-07321332)-3C-like SARS-CoV-2 protease complexation: a ligand Gaussian accelerated molecular dynamics study

Coronavirus 3C-like protease (3CLpro) is found in SARS-CoV-2 virus, which causes COVID-19. 3CLpro controls virus replication and is a major target for target-based antiviral discovery. As reported by Pfizer, Nirmatrelvir (PF-07321332) is a competitive protein inhibitor and a clinical candidate for orally delivered medication. However, the binding mechanisms between Nirmatrelvir and 3CLpro complex structures remain unknown. This study incorporated ligand Gaussian accelerated molecular dynamics, the one-dimensional and two-dimensional potential of mean force, normal molecular dynamics, and Kramers' rate theory to determine the binding and dissociation rate constants (k_off and k_on) associated with the binding of the 3CLpro protein to the Nirmatrelvir inhibitor. The proposed approach addresses the challenges in designing small-molecule antiviral drugs.

[Estimation of molecular clock of Mycobacterium tuberculosis based on whole genome sequencing data]

Objective: To analyze the genomic mutation of Mycobacterium tuberculosis (M. tuberculosis) isolated in endogenous activation period and estimate the molecular clock based on the whole genome sequencing data. Methods: Literatures of the whole genome research of endogenous reactivated tuberculosis were retrieved, and the corresponding whole genome sequencing data were downloaded. We extracted the single nucleotide polymorphisms (SNPs) and strain isolation time of initial treatment and relapse of tuberculosis cases, explored the relationship between the different SNPs and interval between initial treatment and relapse by Poisson regression model, calculated the M. tuberculosis molecular clock, and estimated the mutation rate. Results: When the generation time of M. tuberculosis was 18 hours, the mutation rate in 0-2 years, i.e. short-term endogenous activation, was 6.47×10^-10 (95%CI: 5.59×10^-10-7.44×10^-10), which was significantly higher than that in 2-14 years in long term endogenous activation (3.27×10^-10, 95%CI: 2.88×10^-10-3.69×10^-10). The mutation rates of 0-, 1-, 2-, 3-, 5- and 7-14 years were 7.10×10^-10, 6.06×10^-10, 4.24×10^-10, 5.34×10^-10, 2.59×10^-10 and 1.26×10^-10 respectively. Conclusions: In the period of endogenous reactivation, the mutation rate of M. tuberculosis decreases with the interval time between initial treatment and relapse, which verifies the clinically observed phenomenon that the relapse often occurs within two years after the initial treatment of tuberculosis.

[Anatomical elucidation and histological study of pelvic autonomic nerve-plane based female fresh cadaver]

Objective: To investigate the rationality of nerve-plane sparing radical hysterectomy (NPSRH) for cervical cancer by observing the anatomical and histological characteristics of pelvic autonomic plane based on fresh cadaver. Methods: From October 2015 to September 2020, 14 fresh female cadavers were anatomically and histologically studied in the Laboratory of Anatomy and Embryology Department, Peking Union Medical College, Chinese Academy of Medical Sciences. The median age of the specimens was 79 years (range: 67 to 92 years). Twenty-eight hemi-pelvic specimens were obtained from 14 fresh female cadavers. NPSRH procedures were simulated in 8 hemi-pelvic cavities to prove its feasibility. Detailed dissection was conducted to recognize nerve plane and to observe the distribution of pelvic nerves in 10 hemipelvis. In the other 10 hemipelvis, whole parametrium tissue was taken from the crossing of ureter and the uterine artery to the ureterovesical entrance and be embedded, then continuous section was performed, and was stained by hematoxylin-eosin staining (HE) to observe the relationship of nerves and vessels. Immunohistochemical staining of S100, tyrosine dehydrogenase (TH), and vasoactive intestinal peptide (VIP) were performed to count and distinguish sympathetic and parasympathetic nerves, respectively. Results: (1) The pelvic autonomic nerve-plane was completely preserved in 7 of 8 hemipelvis by simulating NPSRH. (2) After detailed dissection in 10 hemipelvis, it was found that hypogastric nerve, pelvic splanchnic nerve, and their confluence of inferior hypogastric plexus were distributed in a planar statelocating in the ureteral mesentery and its caudal extension. This nerve plane showed a cross relationship with deep uterine vein and its branches. The bladder branches and vesical venous plexus were closely related to the inferior hypogastric plexus. The middle vesical vein and inferior vesical vein were intact in 7 of 10 hemipelvis, and either vesical vein was missing in 3 of them. It was observed that the vesical venous plexus communicated with the deep uterine vein trunk on the medial side of the nerve plane in 6 hemipelvis, while flowed into the deep uterine vein on the lateral side of the nerve plane in 2 hemipelvis, and in the other 2 hemipelvis it directly flowed into the internal iliac vein. (3) It was revealed that autonomic nerves were continuously distributed beneath the ureteral with sagittal plane by HE staining. The average nerve content below the ureteral width was 70.9% of the total in nerve plane by S100 staining. TH and VIP staining showed that the average number of sympathetic fibers was 13.5 and parasympathetic fibers was 8.2, reminding sympathetic predominated. Conclusion: Pelvic autonomic nerves are mainly distributed within the mesangial plane below the ureter, which provides an anatomic justification for NPSRH.

[Access to liver cancer screening and surveillance in populations in China: an exploratory analysis]

Objective: To systematically quantify the access to screening and surveillance service of liver cancer in populations in China, especially a series of sub-indicators of the availability. Methods: Following the specific indicators applied by the International Agency for Research on Cancer in the session of availability and use of screening practices in several cancer screening handbooks, information about the access/availability of liver cancer screening and surveillance in population in China were collected; the indicators included local policies and guidelines, procedures most commonly used or recommended, population coverage and participation rate, compliance and related factors, treatment rate, acceptability, equity and others. Systematic review approach was used, combined with searching core literatures/monograph, websites of governments and available program reports, for a systematic analysis on the access to liver cancer screening and surveillance in populations in China. Results: A total of 34 journal articles were included from the systematic review and most of which were about the participation of secondary liver screening or surveillance compliance; additional information were mainly obtained from the other sources. Overall, there were clearly recommended screening and surveillance procedures for liver cancer in the three major cancer screening programs funded by the central government of China. It was estimated that 0.09% of the population aged 35-74 years were covered by liver cancer screening in 2019 in China. The overall participation rates of secondary screening ranged from 37.5% to 62.3% in three major programs, the median compliance rate of surveillance was reported as 26.9% (Q₁,Q₃: 23.5%, 41.0%) in the 6 included studies. Two studies reported the factors affecting the participation and compliance. A large-scale multicenter analysis showed that the subject acceptability to alpha fetoprotein test combined with ultrasound screening was as high as 99.3% in high-risk population in urban area. The treatment rate of liver cancer founded by screening, surveillance or follow-up was estimated to be >90% in rural population. No studies of equity were obtained via the systematic review. Conclusions: The public health service programs in China all recommend specific procedures for liver cancer screening in general population and surveillance for high-risk individuals. However, the overall availability needs to be improved, particularly in the indicator of population coverage. Participation rates of screening and compliance rates of surveillance varied among the included programs and the studies, suggesting that the influencing factors need to be further identified. The relatively high subject acceptability suggests the potential demands for screening service. More efforts are needed to address the access to screening and surveillance of liver cancer in populations in China.

[Research progress of sentinel lymph node biopsy technique in cervical cancer]

Cervical cancer is the most common gynecological malignant carcinoma in Chinese women, which seriously threatens women's health. Lymph node metastasis is the most important factor affecting the prognosis and adjuvant treatment of patients with early cervical cancer. Conventional systematic lymphadenectomy has always been a reliable method to detect lymph node metastasis. However, this procedure may affect the quality of life of patients because of high risks of complications. Recently, sentinel lymph node biopsy (SLNB) has been researched aiming to assess the status of pelvic lymph node metastasis intraoperatively, avoid unnecessary lymphadenectomy and achieve the goal of individualized diagnosis and treatment. Exploring efficient tracing methods and pathological ultra-staging is the key to the clinical application of SLNB for cervical cancer, and understanding the latest relevant clinical research progress will help SLNB to be applied in the clinic as soon as possible to benefit patients with cervical cancer.

[An investigation on serum antibody level of varicella-zoster virus in healthy population in Beijing]

Objective: To assess the level and trend of varicella-zoster virus (VZV) antibody among healthy population in Beijing in 2017, after the five-year implementation of the two doses varicella vaccination strategy in 2012, and to provide evidence for scientific evaluation of immunization strategy. Methods: A total of 2 144 subjects in ten age groups from 8 districts of Beijing city were recruited in this study using cross-sectional survey based on multi-stage cluster random sampling method. Serum samples were collected and VZV antibody was detected by ELISA. The influencing factors of antibody concentration and positive rate were analyzed and compared with the study in 2012. The antibody concentration and antibody positive rate were analyzed by nonparametric test and χ² test respectively. Results: The ratio of subjects with registered residence in Beijing city to other provinces was 1∶1. The ratio of male to female was 1∶1.08. The median concentration of VZV antibody was 341.4 (78.6, 1 497.8) mIU/ml, and the total antibody positive rate was 71.1% (1 524/2 144). There were significant differences in antibody positive rate (χ²=736.39, P<0.01) and antibody concentration (χ²=740.34, P<0.01) among different age groups. The antibody positive rate generally increased with age (χ²_trend=7.32, P_trend<0.01). Among 862 children under 14 years old, the antibody positive rate of two doses vaccination 72.8% (182/250) was significantly higher than that of one dose vaccination 51.9% (154/297) (χ²=25.14, P<0.01). There was significant difference between 1-4 years old group (χ²=11.71, P<0.01) and 10-14 years old group (χ²=5.95, P=0.02), but not in 5-9 years old group (χ²=3.00, P=0.07). Compared with the study in 2012, the antibody positive rate increased in 5-9 years old group (χ²=14.35, P<0.01) and decreased in 1-4 years old group (χ²=11.51, P=0.01) in 2017. Conclusion: The recommended varicella booster vaccination has significantly improved the VZV antibody level of children in Beijing city. In the future, it is necessary to explore a more optimized two doses varicella vaccination schedule for children in combination with epidemiological evidence.

[Long non-coding RNA LOC101927476 inhibits invasion, migration, and proliferation of ovarian cancer cell lines]

Objective: To investigate the expression of long non-coding RNA LOC101927476 (LncRNA LOC101927476) in ovarian cancer and its effect on the biological characteristics of ovarian cancer. Methods: Patients with ovarian cancer who underwent surgery in Cancer Hospital of Chinese Academy of Medical Sciences from 2018 to 2019 were selected. The expressions of LOC101927476 in ovarian cancer cells 3AO, OVCA429, TOV21G, A2780, SKOV3, as well as 22 primary tumor tissues and their matched metastatic tumor tissues were detected by real-time quantitative polymerase chain reaction (RT-PCR). Ovarian cancer transcriptome sequencing data from the TCGA database was used to verify the expressions of LOC101927476 and GATA4. 3AO and OVCA429 cells were infected with lentivirus plasmid containing OE-LOC101927476 and single guide RNA (sg-RNA) targeting LOC101927476, respectively. The effects of LOC101927476 on migration and invasion were detected by Transwell and wound healing assay. The effect of LOC101927476 on cell proliferation was detected by cell counting kit-8 (CCK-8) assay. Results: RT-PCR assay showed that 20 out of 22 patients had significantly lower expression of LOC101927476 in their metastatic tumors compared with primary tumors. Transwell assay showed that overexpression of LOC101927476 significantly inhibited the invasion and migration capacities of 3AO cells. The numbers of invading and migrating 3AO cells infected with OE-LOC101927476 lentivirus were (357±63) and (699±65), respectively, lower than (661±95) and (1 024±76) in OE-EV group (P<0.050). In contrast, the numbers of invading and migrating OVCA429 cells with LOC101927476 knockdown were (512±72) and (472±40), respectively, higher than (309±13) and (363±27) in sg-Control group (P<0.050). Wound healing assay results showed that after 48 hours, the percentage of scratch healing of 3AO cells in OE-LOC101927476 group was (10.86±0.63)%, significantly lower than (57.38±4.42)% of OE-EV group (P=0.009). After 24 hours, the percentage of scratch healing of OCVA429 cells in sg-LOC101927476 group was (59.98±1.34)%, significantly higher than (23.15±2.03)% of sg-Control group (P=0.004). CCK-8 assays showed that the OD value of 3AO cells in OE-LOC101927476 group was (2.07±0.08), significantly lower than (2.29±0.04) of OE-EV group (P=0.009). The OD value of OVCA429 cells in sg-LOC101927476 group was (2.13±0.03), significantly higher than (1.93±0.03) of sg-Control group (P=0.001). The relative expression of GATA4 in OE-LOC101927476 group was (1.86±0.25), significantly higher than 1.00 of OE-EV group (P=0.001). In patients with high expression of LncRNA LOC101927476, the expression level of GATA4 was (2.93±0.35), which was higher than (0.29±0.06) of LOC101927476 low expression group (P=0.001). Conclusion: LncRNA LOC101927476 can inhibit the invasion, migration and proliferation of ovarian cancer cells.

Traditional Chinese medicine use may reduce medical utility in patients with asthma: a nationwide population-based retrospective cohort study

BACKGROUND

Many patients with atopic diseases, including asthma, have sought complementary and alternative medicine and traditional Chinese medicine (TCM) treatments. But, limited clinical studies have yet examined TCM effects on medical utility in asthma patients.

AIM

To assess the medical utility of TCM in patients with asthma.

DESIGN

Population-based retrospective cohort study.

METHODS

We performed a 13-year population-based retrospective cohort study. A total of 5235 asthma patients who were TCM users and 5235 propensity-score matched asthma patients who never used TCM were sampled from the Taiwan National Health Insurance Research Database from 2000 to 2012. We compared these two groups of patients to calculate their medical utility, including numbers of emergency visits and hospitalizations until 2013. Univariate analyses were performed using Chi-square tests for dichotomous variables and t-tests for continuous variables. Cox proportional hazard models were conducted to investigate the medical utility of asthma after TCM use.

RESULTS

Compared with non-TCM patients, TCM patients had a significantly decreased medical utility of asthma admission [adjusted odds ratio (OR) = 0.63; 95% confidence interval (CI): 0.46-0.85; P < 0.05], especially in patients who used TCM for >60 days. Asthma medical utility in asthma emergencies was significantly higher for male than for female patients (adjusted OR = 1.45; 95% CI: 1.08-1.96). The most frequently used TCMs for asthma control or cough treatment were antitussive agents.

CONCLUSION

This population-based retrospective cohort study showed a significantly decreased medical utility of emergency visits and admissions in TCM patients, especially using TCM for >60 days.

[Association between inflammation activity of left atrial epicardial adipose tissue measured by 18F-FDG PET/CT and atrial fibrillation]

Objective: To explore the association between inflammation activity of left atrial epicardial adipose tissue (LA-EAT) measured by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and atrial fibrillation (AF). Methods: A total of 78 patients with AF, who underwent ¹⁸F-FDG PET/CT in the Nuclear Medicine Department of the Third Affiliated Hospital of Soochow University due to abnormally elevated levels of tumor indicators or malignant tumors from March 2018 to December 2019, were enrolled in this retrospective study. According to the examination date of PET/CT and basic characteristics of AF patients (gender, age), a 1∶1 propensity score matching was used to enroll a non-AF control group (78 patients). The maximum standard uptake value of left atrial epicardial tissue (LA-EAT FDG SUV_max) and total EAT volume (V-EAT) were measured by ¹⁸F-FDG PET/CT. Left ventricular ejection fraction (LVEF) and left atrial diameter (LAD) were obtained by echocardiography. Blood lipids and biomarkers of inflammation were measured. The differences of clinical data and EAT-related indicators were compared between the AF group and control group. Logistic multivariate regression analysis was used to determine the related factors of AF. Then the receiver operating characteristic (ROC) curve was used to determine the cutoff value of LA-EAT FDG SUV_max on the diagnosis of AF. Univariate and multivariate logistic regression analysis were used to analyze the relationship between the increase of LA-EAT FDG SUV_max and AF. Results: The age was (66.9±10.2) years and there were 55 males (70.5%) in the AF group. The age was (66.9±8.0) years, and there were 52 males (66.7%) in the control group (both P>0.05). The LAD ((44.2±5.8) mm vs. (35.4±4.4) mm), V-EAT ((122.1±42.0) cm³ vs. (91.6±34.5) cm³), and LA-EAT FDG SUV_max ((1.6±0.3) vs. (1.4±0.2)) values were significantly higher, while LVEF ((60.1±4.7)% vs. (63.9±2.9)%) was lower in the AF group than in the control group (P all<0.001). Multivariate logistic regression analysis showed that LAD (OR=1.340, 95%CI 1.195-1.502), V-EAT (OR=1.016, 95%CI 1.001-1.031), and LA-EAT FDG SUV_max (OR=1.375, 95%CI 1.095-1.723) were positively correlated with AF, LVEF (OR=0.781, 95%CI 0.659-0.926) was negatively correlated with AF(P all<0.05). The area under the ROC curve of LA-EAT FDG SUV_max for diagnosis of AF was 0.680 (95%CI 0.597-0.764, P<0.001), and the best cut-off value was 1.415 with a sensitivity of 65.4% and specificity of 61.5%. After adjusting for high-density lipoprotein cholesterol, LVEF, LAD and V-EAT, LA-EAT FDG SUV_max≥1.415 was independently associated with AF (OR=2.982, 95%CI 1.122-7.926, P=0.010). Conclusions: The inflammatory activity of LA-EAT measured by ¹⁸F-FDG PET/CT is an independent risk factor of AF, and the increased inflammatory activity of LA-EAT is positively correlated with AF.

Does conventional early life academic excellence predict later life scientific discovery? An assessment of the lives of great medical innovators

BACKGROUND

Perhaps, as never before, we need innovators. With our growing population numbers, and with increasing pressures on our education systems, are we in danger of becoming more rigid and formulaic and increasingly inhibiting innovation? When young can we predict who will become the great innovators? For example, in medicine, who will change clinical practice?

AIMS

We therefore determined to assess whether the current academic excellence approach to medical school entrance would have captured previous great innovators in medicine, assuming that they should all have well fulfilled current entrance requirements.

METHODS

The authors assembled a list of 100 great medical innovators which was then approved, rejected or added to by a jury of 12 MD fellows of the Royal Society of Canada. Two reviewers, who had taken both the past and present Medical College Admission Test as part of North American medical school entrance requirements, independently assessed each innovator's early life educational history in order to predict the innovator's likely success at medical school entry, assuming excellence in all entrance requirements.

RESULTS

Thirty-one percent of the great medical innovators possessed no medical degree and 24% would likely be denied entry to medical school by today's standards (e.g. had a history of poor performance, failure, dropout or expulsion) with only 24% being guaranteed entry. Even if excellence in only one topic was required, the figure would only rise to 41% certain of medical school entry.

CONCLUSION

These data show that today's medical school entry standards would have barred many great innovators and raise questions about whether we are losing medical innovators as a consequence. Our findings have important implications for promoting flexibility and innovation for medical education, and for promoting an environment for innovation in general.

[Non-alcoholic fatty liver disease increases the incidence rate of type 2 diabetes mellitus: a cohort study based on a rural town elderly population of southern Jiangsu]

Objective: To investigate the impact of non-alcoholic fatty liver disease (NAFLD) on the incidence of type 2 diabetes mellitus (T2DM) in an elderly population. Methods: A rural elderly population of Kunshan city, Jiangsu Province were used as the research subject. Prior diabetes mellitus, heavy alcohol consumption and incomplete data were excluded from prospective cohort study analysis. Annual physical examination and follow-up were conducted from 2007 to 2016. T2DM onset, death and loss to follow-up visits were observed as the research subject end points. According to the baseline physical examination results, the study subjects were divided into NAFLD and control groups, and further baseline data of both groups were analyzed whether there were match. The cumulative incidence rate of T2DM were statistically analyzed and compared between the two groups. Simultaneously, the relationship between the two groups of various indexes and the newly developed T2DM were analyzed using Kaplan-Meier. The variables with P < 0.1 were selected and incorporated into the Cox proportional hazard regression model. The impact of NAFLD on the incidence of T2DM was analyzed in an elderly population. Results: At baseline, there were statistically significant differences in the distribution of age, sex, waist circumference, body mass index, systolic blood pressure, diastolic blood pressure, direct bilirubin, blood urea nitrogen and triglycerides between NAFLD and non-NAFLD groups. However, fasting blood glucose, serum creatinine, total bilirubin, total cholesterol, low density lipoprotein cholesterol and high-density lipoprotein cholesterol had no statistically significant differences between the two groups. After nine years of follow-up, 207 newly developed T2DM cases, 52 NAFLD cases and 155 control group were selected as the study subjects. The cumulative incidence rates were 4.25%, 10.34%, and 3.55%, respectively. Kaplan-Meier analysis result showed that there were statistically significant differences in the cumulative incidence rates between the two groups from five-year. NAFLD had increased the T2DM risk in an elderly population by approximately 2.14 times (2.14 CI: 1.132 ~ 4.047) at five-year, and then had increased year by year thereafter. Univariate analysis showed that T2DM risk was 2.76 times higher in NAFLD than non-NAFLD groups (95% CI: 2.015 ~ 3.777). After adjustment for gender, age, body mass index, waist circumference, systolic blood pressure, diastolic blood pressure, serum creatinine, triglyceride, total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol, T2DM risk ratio was 1.68 times higher in NAFLD than control groups (95% CI: 1.163 ~ 2.425). Conclusion: NAFLD is an independent long-term risk factor for the T2DM onset in an elderly population.

[Epidemiological characteristics of Chlamydia pneumoniae in cases with acute respiratory infection in Beijing, 2015-2019]

Objective: To analyze the epidemiological characteristics of Chlamydia pneumoniae infection among patients with acute respiratory infection in Beijing from 2015 to 2019. Methods: The epidemiological data of acute respiratory infection patients from 35 sentinel hospitals in Beijing were collected by the respiratory pathogen surveillance system in Beijing. The clinical samples were collected to detect Chlamydia pneumoniae, and the sequence of the VD4 region of the ompA gene in positive samples was analyzed. Results: From January 2015 to December 2019, the overall positive rate of Chlamydia pneumoniae among patients with acute respiratory infection in Beijing was 0.34% (129/37 460). The positive rate of Chlamydia pneumoniae generally increased in March, reaching the peak in May, and started to drop in July, with a duration of about 5-8 months. The epidemic season in different years fluctuated by 1-2 months. The positive monthly rate of Chlamydia pneumoniae was no less than 0.30% in every epidemic season. The positive rate of Chlamydia pneumoniae was the highest in the 5-44 years old group and the highest in 10-14 year-olds. The risk of Chlamydia pneumoniae infection increased with age in patients younger than 25 years old and decreased in those older one aged than 25 years of age. The positive rates in male and female patients were 0.33% (68/20 830) and 0.37% (61/16 528), respectively, and there was no significant difference between the two groups (χ²=0.486, P=0.486). The positive rate of Chlamydia pneumoniae in patients with common pneumonia was higher than that in patients with upper pneumonia and severe pneumonia (χ²=36.797, P<0.01). Other respiratory pathogens were also detected in the Chlamydia pneumoniae samples, and the top four pathogens appeared as Haemophilus influenzae (15 cases), Streptococcus pneumoniae (13 cases), Rhinovirus (8 cases), and Stenotrophomonas maltophilia (7 cases). 101 strains of 129 Chlamydia pneumoniae positive samples were identified as type A by sequencing. Conclusions: The annual epidemic pattern of Chlamydia pneumoniae in Beijing, is unimodal, and the epidemic season generally appears from March to July. The seasonal characteristics of Chlamydia pneumoniae in Beijing can be used for the differential diagnosis of Chlamydia pneumoniae from other respiratory pathogens. Chlamydia pneumoniae is most common in people aged 5-44 years, and the primary genotype is type A. People aged 10-44 years old suffer the highest incidence. If the nucleic acid positive rate of Chlamydia pneumoniae exceeds 0.30% for two consecutive months, the high prevalence period of Chlamydia pneumoniae can be preliminarily expected. Chlamydia pneumoniae infection has a higher probability of progressing to severe pneumonia from general pneumonia.

[Clinical characteristics of patients infected with Chlamydia pneumoniae in Beijing from 2015 to 2019]

Objective: To aralyze the clinical characteristics of Chlamydia pneumoniae infection in Beijing. Methods: Based on Beijing Respiratory Pathogen Surveillance System, acute respiratory infection patients were recruited from 35 different types of sentinel hospitals in Beijing. Their epidemiological and clinical data were systematically collected and clinical specimens were also obtained. Nuclear acid testing was performed for 30 types of respiratory pathogens (including Chlamydia pneumoniae). The identified patients of Chlamydia pneumoniae infection were divided into two groups, the acute upper respiratory tract infection (AURI) group and pneumoniae group. The differences in clinical characteristics, laboratory examination and prognosis were compared by using independent sample t test, Mann-Whitney U test, χ² test or Fisher's exact probability test. Results: A total of 119 patients of Chlamydia pneumoniae infection were included, including 12 patients in the AURI group and 107 patients in pneumoniae group. Chlamydia pneumoniae infection mainly occurred in people aged from 5 to 44 years, accounting for 81.5% (97/119). The three most common clinical symptoms were cough (92.4%, 110/119), fever (88.8%, 95/107), and sputum production (76.5%, 91/119). White blood cell counts increased in 39.3% (46/117) of patients. Neutrophile granulocyte proportion increased in 39.7% (46/116) of patients. Platelet count increased in 36.9% (41/111) of patients. An increase of the creatine kinase MB isoenzyme (CKMB) was observed in 12 pneumonia patients (24.5%, 12/49). Radiological examination showed that 90.6% (87/105) of patients in the pneumoniae group had pulmonary parenchymal changes; the lesion occurred most commonly in the lower right lung lobe (34.3%, 36/105) and the lower left lung lobe (27.6%, 29/105). Although 73.8% (79/107) of patients in the pneumoniae group were hospitalized, no case received intensive care unit or mechanical ventilation. As to outcomes, one patient developed respiratory failure and 6 patients suffered myocardial injury. No death was observed in this study. The median days of hospitalization and course of illness for pneumonia patients M(P₂₅,P₇₅) were 10.0 (7.0, 13.0) days and 18.0 (13.5, 22.0) days, respectively. Conclusion: Generally, Chlamydia pneumoniae infections in Beijing from 2015 to 2019 were mild, and the main clinical manifestations were cough, fever and sputum. However, most patients in the pneumoniae group caused by Chlamydia pneumoniae still required hospitalization but with a better outcome.

Correction: Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies

Correction for ‘Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies’ by Bo-Cheng Huang et al., Chem. Sci., 2021, DOI: 10.1039/D1SC01748A.

Development of a structure-based computational simulation to optimize the blocking efficacy of pro-antibodies

The on-target toxicity of monoclonal antibodies (Abs) is mainly due to the fact that Abs cannot distinguish target antigens (Ags) expressed in disease regions from those in normal tissues during systemic administration. In order to overcome this issue, we “copied” an autologous Ab hinge as an “Ab lock” and “pasted” it on the binding site of the Ab by connecting a protease substrate and linker in between to generate a pro-Ab, which can be specifically activated in the disease region to enhance Ab selectivity and reduce side effects. Previously, we reported that 70% of pro-Abs can achieve more than 100-fold blocking ability compared to the parental Abs. However, 30% of pro-Abs do not have such efficient blocking ability. This is because the same Ab lock linker cannot be applied to every Ab due to the differences in the complementarity-determining region (CDR) loops. Here we designed a method which uses structure-based computational simulation (MSCS) to optimize the blocking ability of the Ab lock for all Ab drugs. MSCS can precisely adjust the amino acid composition of the linker between the Ab lock and Ab drug with the assistance of molecular simulation. We selected αPD-1, αIL-1β, αCTLA-4 and αTNFα Ab as models and attached the Ab lock with various linkers (L1 to L7) to form pro-Abs by MSCS, respectively. The resulting cover rates of the Ab lock with various linkers compared to the Ab drug were in the range 28.33–42.33%. The recombinant pro-Abs were generated by MSCS prediction in order to verify the application of molecular simulation for pro-Ab development. The binding kinetics effective concentrations (EC-50) for αPD-1 (200-250-fold), αIL-1β (152-186-fold), αCTLA-4 (68-150-fold) and αTNFα Ab (20-123-fold) were presented as the blocking ability of pro-Ab compared to the Ab drug. Further, there was a positive correlation between cover rate and blocking ability of all pro-Ab candidates. The results suggested that MSCS was able to predict the Ab lock linker most suitable for application to αPD-1, αIL-1β, αCTLA-4 and αTNFα Ab to form pro-Abs efficiently. The success of MSCS in optimizing the pro-Ab can aid the development of next-generation pro-Ab drugs to significantly improve Ab-based therapies and thus patients' quality of life.

The pro-Ab blocks the Ag binding site using an Ab lock. We designed a method which uses structure-based computational simulation (MSCS) to predict the cover rate of Ab locks with various linkers and select the suitable linker for each Ab.

Anti-TNF Alpha Antibody Humira with pH-dependent Binding Characteristics: A constant-pH Molecular Dynamics, Gaussian Accelerated Molecular Dynamics, and In Vitro Study

Humira is a monoclonal antibody that binds to TNF alpha, inactivates TNF alpha receptors, and inhibits inflammation. Neonatal Fc receptors can mediate the transcytosis of Humira-TNF alpha complex structures and process them toward degradation pathways, which reduces the therapeutic effect of Humira. Allowing the Humira-TNF alpha complex structures to dissociate to Humira and soluble TNF alpha in the early endosome to enable Humira recycling is crucial. We used the cytoplasmic pH (7.4), the early endosomal pH (6.0), and pKa of histidine side chains (6.0-6.4) to mutate the residues of complementarity-determining regions with histidine. Our engineered Humira (W1-Humira) can bind to TNF alpha in plasma at neutral pH and dissociate from the TNF alpha in the endosome at acidic pH. We used the constant-pH molecular dynamics, Gaussian accelerated molecular dynamics, two-dimensional potential mean force profiles, and in vitro methods to investigate the characteristics of W1-Humira. Our results revealed that the proposed Humira can bind TNF alpha with pH-dependent affinity in vitro. The W1-Humira was weaker than wild-type Humira at neutral pH in vitro, and our prediction results were close to the in vitro results. Furthermore, our approach displayed a high accuracy in antibody pH-dependent binding characteristics prediction, which may facilitate antibody drug design. Advancements in computational methods and computing power may further aid in addressing the challenges in antibody drug design.

Characterization of sedimentary phosphorus in Lake Erie and on-site quantification of internal phosphorus loading

Lake Erie harmful algal blooms and hypoxia are two major environmental problems, and have severe impacts on human health, aquatic ecosystems, and the economy. However, little is known about internal loading of phosphorus (P) from sediments, which pose a challenge for assessing the efficacy of current conservation measures on the improvement of lake water quality. A modified Hedley's extraction procedure was employed to analyze representative sediment samples collected from the Lake Erie basin for assessing sedimentary P stock, potential availability for release into lake water, and internal P loading. Inorganic and organic P in the sediments were characterized by sequential extractions in H₂O, 0.5 M NaHCO₃, 0.1 M NaOH, and 1.0 M HCl, respectively. In the 0 - 10 cm sediment, total P stock was 172, 191, and 170 metric tons km^-2 in the western, central, and eastern basins, respectively. Sedimentary P seems unlikely to contribute to internal P loading in the western basin, while in the eastern basin it can potentially contribute to an internal loading of 359 metric tons P yr^-1. In the central basin, 41% of organic P, 15% of non-HCl extractable inorganic P, and 9.7% of residual P in the 0 - 10 cm sediment is potentially available for release into lake water; in the 10 - 20 cm sediment, organic P extracted by NaHCO₃ and NaOH is also partially available. The central basin potentially contributes to internal P loading at a total amount of 10,599 metric tons yr^-1. Internal P loading may not contribute to HABs in the western basin, but it can cause and maintain hypoxia in the central basin and delay the recovery of lake water quality for a lengthy time period in response to external P reduction measures.

Effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs

Ruminants can tolerate moderate concentrations of dietary tannin, making it feasible to replace corn with sorghum in ruminant diets; however, conditioning temperature of pelleted total mixed ration (PTMR) greatly affects nutrient digestibility. The objective was to determine effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs. This was a 2 × 3 factorial study, with corn and sorghum and three conditioning temperatures (65, 75 and 85 °C) in a randomized complete design, with 36 lambs (120 ± 10.2 d and 24.9 ± 3.3 kg) grouped by weight and randomly allocated. The resulting six PTMRs were referred to as 65-S, 75-S and 85-S for sorghum-based diets, and 65-C, 75-C and 85-C for corn-based diets, for low, medium and high pelleting temperatures, respectively. There was no grain type × conditioning temperature (Grain × Temp) interaction on growth performance and apparent nutrient digestibility. Furthermore, grain type did not affect DM intake (DMI), average daily gain (ADG) or feed conversion ratio (FCR) of fattening lambs. Pelleting at 75 °C improved ADG (P < 0.03) and FCR (P < 0.02) of fattening lambs compared to other temperatures. There was a Grain × Temp interaction (P < 0.01) on ruminal pH (lowest in lambs fed 75-S). There tended (P = 0.07) to be a Grain × Temp interaction for total volatile fatty acid (VFA), and there were Grain × Temp interactions for molar proportions of acetate (P < 0.04), butyrate (P < 0.03) and branch-chained VFA (P < 0.01). Lambs fed sorghum-based PTMR had greater molar proportion of propionate (P < 0.03) and lower acetate to propionate ratio (A:P, P < 0.04). Lambs fed sorghum-based PTMR had higher plasma concentrations of urea nitrogen (N) (P < 0.03), glucose (P < 0.01) and alkaline phosphatase (P < 0.05), whereas other blood metabolites were not affected by treatments. There were Grain × Temp (P < 0.03) interactions for color coordinates of longissimus and mid-gluteal muscle. Lambs fed sorghum-based PTMR had lower (P < 0.01) dressing percentage and meat quality than those fed corn-based PTMR. We concluded that sorghum can replace corn in lamb diets without compromising growth performance and feed efficiency; furthermore, feeding sorghum vs corn improved rumen fermentation, with reduced A:P ratio and enhanced N and glucose utilization. Finally, pelleting at 75 °C increased feeding value of either sorghum- or corn-based PTMR for fattening lambs.

Large Isospin Asymmetry in ^{22}Si/^{22}O Mirror Gamow-Teller Transitions Reveals the Halo Structure of ^{22}Al

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

[Efficacy and safety of laparoscopic radical hysterectomy for early cervical adenocarcinoma]

Objective: To investigate the efficacy and safety of laparoscopic radical hysterectomy for early cervical adenocarcinoma. Methods: A retrospective observational study was performed by reviewing medical records of patients with staging Ⅰb1-Ⅱa2 International Federation of Gynecology and Obstetrics (FIGO, 2009) cervical adenocarcinoma who underwent laparoscopic or abdominal radical hysterectomy from 2007 to 2017 in the Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences. The difference among clinicopathologic characteristics, surgery-related parameters and complications, and prognosis were analyzed between the laparoscopic group and abdominal group. Results: Two hundreds and ninety-three patients were included with 88 cases in laparoscopic group and 205 cases in abdominal group. （1） There was no significant difference in clinicopathologic characteristics between the two groups （all P>0.05）, including age, body mass index, menopause status, history of abdominal surgery, clinical stage, tumor diameter, neoadjuvant chemotherapy, differentiation, lymph-vascular space invasion, positive of surgical margin, parametrial invasion, and lymph node metastasis. But the abdominal group showed a higher proportion of deep stromal invasion (38.5% vs 25.0%, P<0.05). No significant difference was observed between two groups with number of lymph nodes resected, urinary catheter retention, short-term surgical complications (including ureteral injury, ileus, infection, hydronephrosis and poor wound healing), and long-term complications (including voiding dysfunction, defecation dysfunction and lower limb edema； all P>0.05）. （2） The laparoscopic group was significantly associated with a longer operation time [(260±51) minutes vs (244±53) minutes, P<0.05], but less bleeding (100 ml vs 300 ml, P<0.01), shorter hospital stay [(13±5) days vs (16±8) days, P<0.01] and lower incidence of lymphedema (12.5% vs 27.8%, P<0.01). （3） The 5-year progression-free survival (PFS; 85.7% vs 86.4%, P=0.971) and 5-year overall survival (OS; 91.4% vs 93.0%, P=0.657) of laparoscopic group were comparable to that of abdominal group. （4） Multivariate analysis demonstrated that lymph node metastasis (HR=2.44, 95%CI: 1.16-5.15, P=0.019) was independent poor prognostic factors related to PFS, while adenosquamous carcinoma (HR=2.54, 95%CI: 1.02-6.35, P=0.046), lymph-vascular space invasion (HR=3.86, 95%CI: 1.60-9.33, P=0.003) and lymph node metastasis (HR=5.92, 95%CI: 2.45-14.34, P<0.01) were independent poor prognostic factors related to OS. The laparoscopy surgery was not an independent poor prognostic factor (P=0.396). Conclusion: The laparoscopic radical hysterectomy for early cervical adenocarcinoma has comparable prognosis to abdominal radical hysterectomy with a higher surgery quality.

Computational modeling of cyclic peptide inhibitor-MDM2/MDMX binding through global docking and Gaussian accelerated molecular dynamics simulations

MDM2 and MDMX are potential targets for p53-dependent cancer therapy. Peptides are key in cellular immunology and oncology, and cyclic peptides generally have higher half-life than their linear counterparts. However, prediction of cyclic peptide-protein binding is challenging with normal molecular simulation approaches because of high peptide flexibility. Here, we used global peptide docking, normal molecular dynamics, Gaussian accelerated molecular dynamics (GaMD), two-dimensional (2D) potential of mean force (PMF) profiles, and solvated interaction energy (SIE) techniques to investigate the interactions of MDM2/MDMX with three N-to-C-terminal cyclic peptide-based inhibitors. We determined the possible cyclic peptide-MDM2/MDMX complex structures via 2D PMF profiles and SIE calculations. Our findings increase the accuracy of peptide-protein structural prediction, which may facilitate cyclic peptide drug design. Advancements in the computational methods and computing power may further aid in addressing the challenges in cyclic peptide drug design. Communicated by Ramaswamy H. Sarma.

[Value of absolute quantification of myocardial perfusion by PET in detecting coronary microvascular disease in patients with non-obstructive coronaries]

Objective: To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries. Methods: We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF<2.17 ml·min(-1)·g(-1). Results: Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ(2)=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ(2)=0.915, P=0.339). RMBF ((0.83±0.14) ml·min(-1)·g(-1) vs. (0.82±0.17) ml·min(-1)·g(-1)), SMBF ((2.13±0.60) ml·min(-1)·g(-1) vs. (1.91±0.50) ml·min(-1)·g(-1)) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions: CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.

[Outcomes of implanting porcine small intestinal submucosa mesh in rabbit vesicovaginal space]

Objective: To assess surgical outcomes of implanted porcine small intestinal submucosa (SIS) mesh in the rabbit vesicovaginal space (VVS) and explore its application value in pelvic floor reconstruction surgery. Methods: Sixteen male rabbits were randomly divided into four groups, and each group had four rabbits. All groups of rabbits were implanted with SIS mesh in the vesicovaginal space. They were humanely killed after a postoperative period of 7, 30, 90 and 180 days by group. The grafted area was removed with the surrounding bladder and vaginal tissues. The specimens were embedded in paraffin and then stained with HE and Masson's trichrome stains for visual observations, cells counts, and assessment of tissues and collagen fibers. Results: (1) After HE staining, a large number of inflammatory response cells mainly eosinophils and lymphocytes infiltrated around the SIS mesh in 7 days group, and neovascularization was observed, the infiltration area of inflammatory response cells further increased in 30 days group, the infiltration area of inflammatory response cells significantly reduced in 90 days group, while the inflammatory response basically subsided in 180 days group. (2) After Masson's trichromestaining, the collagen structure of SIS mesh in 7 days group was clear and intact. While, the collagen structure of SIS mesh was partially degraded in 30 days group, the SIS meshes of 4 rabbits were completely degraded, but the collagen fragments of SIS remained in 90 days group. In 180 days group, the SIS mesh of all rabbits was degraded, and one of them had the formation of new collagen fibers. Conclusions: SIS mesh implanted into the VVS of rabbits can lead to a transient non infective inflammatory reaction, which could be completely degraded and a small amount of new collagen fibers could be produced after 180 days of implantation. Which shown that SIS mesh should be used cautiously in pelvic floor reconstruction surgery.

[Cost-effectiveness analysis of rabies immunization strategy based on dynamic-decision tree model]

Objective: To evaluate the cost-utility of different immunization strategies for rabies in China, and to provide a reference for determining the optimal immunization strategy. Methods: The system dynamics model was used to simulate the epidemic of canine rabies and a decision tree model was conducted to analysis different immune strategies. Relevant probabilities were obtained through literature search and on-site investigation. Sensitivity analysis was used to explore the important influenced factors. Results: At baseline, from a social perspective, 70% vaccination of dogs was the optimal strategy compared to current vaccination strategy (43% vaccination in dogs, human category-Ⅱ exposure vaccination/category-Ⅲ exposure vaccination combined with RIG). The total cost was 14 084 354 CNY, and the total utility value was 22 078 616.23 QALYs, and the incremental cost-utility ratio was-62 148 147 CNY/QALY; if human vaccination was considered, 55% vaccination of dogs combined with strategy one was the optimal strategy, its incremental cost-utility ratio was-444 620 557 CNY/QALY. The probability that an injured dog carries rabies virus was the most sensitive parameter. When it was greater than 0.005 03, strategy four was the optimal strategy. When it was less than 82/100 000, strategy one was the optimal strategy; when it was between 82/100 000 and 120/100 000, strategy two was the optimal strategy; when it was between 120/100 000 and 503/100 000, strategy two was the optimal strategy. Conclusion: It was conducive to increase the vaccination coverage of canine for the prevention and control of rabies.

P841Derivation and validation of novel score system for predicting all-cause death and myocardial infarction in coronary artery ectasia

Background

Coronary artery ectasia (CAE) bears high risk of death and myocardial infarction. Risk stratification in CAE patients is crucial for their management, but there were no risk score systems intended for risk evaluation of CAE patients so far.

Methods

In a retrospective cohort of 595 patients with CAE, we collected the baseline characteristics (clinical history, biomarkers and quantitative coronary angiography variables). Follow-up were conducted and the end-point event was the composite of all-cause death and non-fatal myocardial infarction. The candidate predictors of end-point event were analyzed using Cox proportional hazards regression models to derive a risk score in the form of nomogram. The predictive performance and discriminative ability of the novel nomogram were determined by concordance index (C-index) and calibration curve, that were validated internally. Risk stratification by nomogram-predicted risk score was further evaluated.

Results

During a median follow-up time of 62.3 months, 26 all-cause deaths and 37 non-fatal myocardial infarctions were identified. The final risk-prediction model named ABCD-CAE score included four items: age (A), Brain natriuretic peptide (B), high sensitivity C-reactive protein (C) and maximum Dilated area of ectatic lesions (D). The nomogram yielded a C-index for end-point event of 0.72 (95% confidence interval, 0.64 - 0.79). The calibration curve demonstrated that there is good agreement between prediction by nomogram and actual observation of end-point events. Compared with the low-risk group (score ≤100), the risk of composite events was significantly increased in the intermediate-risk group (score: 100–130) and high-risk group (score >130) [hazard ratio (95% confidence interval): 2.23 (1.23–4.06), P=0.008 and 7.02 (3.81–12.97), P<0.001 respectively].

ABCD-CAE nomogram for risk prediction

Conclusions

The ABCD-CAE score is a simple four-item risk score, that provides a clinically useful tool for the risk prediction of all-cause death and myocardial infarction in patients with CAE. This user-friendly tool might support clinical decision making for the management of CAE.

[Efficacy and side effect analysis of paclitaxel liposome for neoadjuvant chemotherapy in locally advanced cervical cancer]

Objective: To investigate the efficacy and side effect of paclitaxel liposome for neoadjuvant chemotherapy (NACT) in locally advanced cervical cancer. Methods: This study were included 265 cervical cancer patients staging Ⅰb2 and Ⅱa2 who underwent paclitaxel-platinum NACT followed by radical surgery from June 2008 to December 2016 in the Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences. All patients were classified into two groups with 106 patients in paclitaxel liposome group and 159 patients in traditional paclitaxel group. The difference in clinicopathologic characteristics, efficacy and side effect were analyzed retrospectively between the two groups. Results: (1) Clinicopathologic characteristics: there were no significant difference in clinicopathologic characteristics between the two groups, including age, body mass index, clinical stage, pathological histology, cycles of NACT, combined platinum regimen, lymph-vascular space invasion, lymph node metastasis, deep stromal invasion, and postoperative adjuvant therapy (all P>0.05). (2) Efficacy: after NACT, the overall response occurred in 90 (15 complete response plus 75 partial response) of 106 cases in the paclitaxel liposome group versus 131 (21 complete response plus 110 partial response) of 159 cases in the traditional paclitaxel group without statistical significance (84.9% vs 82.4%; χ(2)=0.291, P=0.590). A total of 248 patients received surgery after NACT and were evaluable in survival. The 5-year recurrence-free survival (RFS) rate and 5-year overall survival (OS) rate of these patients was 85.1% and 88.2%. The 5-year RFS rate in the paclitaxel liposome group was 85.9% compared with 85.2% in the traditional paclitaxel group, while the corresponding 5-year OS rate was 88.5% and 88.7%, respectively. There was no statistically significant difference in efficacy between the two groups (P=0.968, P=0.797). (3) Side effect: the incidence of allergic reaction between the paclitaxel liposome group and the traditional paclitaxel group was 0 versus 1.9% (3/159) without statistical significance (P=0.277). But the incidence of neurotoxicity in the paclitaxel liposome group significantly decreased compared with the traditional paclitaxel group (6.6% vs 15.7%, P<0.05), as well as the incidence of alopecia (67.9% vs 79.2%, P<0.05) and myalgia (17.9% vs 28.9%, P<0.05). However, significant differences were not found in terms of hematological toxicity, gastrointestinal reaction, and hepatic function damage (P>0.05). Conclusion: In paclitaxel-platinum NACT of local advanced cervical cancer, paclitaxel liposome can achieve similar efficacy compared with traditional paclitaxel, but paclitaxel liposome is helpful in decreasing the toxicity of neurotoxicity, alopecia and myalgia.

Antimicrobial resistance and virulence genes of Streptococcus isolated from dairy cows with mastitis in China

Streptococcus is a major mastitis-causing pathogen in dairy cows. To investigate the prevalence, antimicrobial resistance and virulence gene of Streptococcus in mastitic milk, a total of 735 mastitic raw milk samples from dairy cows in 11 provinces of China were collected and tested. Antimicrobial resistance of Streptococcus isolates was determined by disc diffusion against 8 classes 29 antimicrobial agents, and Streptococcus resistant genes and virulence genes were determined by PCR and agarose gel electrophoresis. A total of 64 (8.71%) isolates of Streptococcus were isolated and identified using biochemical profiling, including 22 isolates of Streptococcus agalactiae, 13 isolates of Streptococcus dysgalactiae, and 29 isolates of Streptococcus uberis. Out of 64 resistant Streptococcus isolates, all isolates (100%) were resistant to 3 or more antimicrobials. The most frequency (n = 18, 28.12%) of the isolates were multi-resistant to 5-7 antimicrobials and the highest multi-resistant number was 29 (n = 1, 1.56%). Streptococcus isolates had the highest resistance rate to tetracycline (98.44%) and oxacillin (98.44%), followed by penicillin G (96.88%) and doxycycline (96.88%), and the lowest resistance was observed with respect to ciprofloxacin (1.56%). A total of 16 antimicrobials resistance genes with 25 combination patterns were detected in the isolates. The gene combination of Sul1/Sul2/Sul3 + gyrA/parC + cat1/cat2 was the most common pattern (12.5%). The correlation between resistant phenotypes and resistance genes in Streptococcs was 35.87%. A total of 7 virulence genes were detected and 59 (92.19%) isolates harbored at least one gene. Twenty-four classes of gene patterns were found in the isolates and the patterns of bca (9.38%) and cfb (9.38%) were the most prevalent form. In conclusion, the issue of drug resistance of Streptococcus is still a great concern in cattle health in China.

[Comparative study of three-dimensional versus two-dimensional laparoscopic C1 radical hysterectomy for cervical cancer]

Objective: To compare the clinical effects and the subjective perception of surgeons with three-dimensional (3D) and two-dimensional (2D) laparoscopic C1 radical hysterectomy surgeries for cervical cancer. Methods: The retrospective cohort study was conducted. The clinicopathological data of 101 patients with cervical cancer who received C1 laparoscopic radical hysterectomy (C1-LRH) surgery from June 2015 to August 2017 were collected. Of all patients, 42 cases undergoing 3D laparoscopic surgery and 59 cases undergoing 2D laparoscopic surgery were respectively allocated into the C1-3DLRH group or C1-2DLRH group. The clinical effect and the subjective perception of surgeons were compared between the two groups. Results: (1) There was no significant difference between the C1-3DLRH group and C1-2DLRH group in terms of age, body mass index (BMI), International Federation of Gynecology and Obstetrics (FIGO) stage, pathologic type, etc. (all P>0.05). Compared with C1-2DLRH group, the operation time was significantly shortened [(192±54) vs (221±54) minutes, P<0.01], blood loss was significantly less [(102±88) vs (167±117) ml, P<0.01], and the success rate of inferior hypogastric plexus (IHP) bladder branch preservation was significantly increased [86% (36/42) vs 66% (39/59), P<0.05] in C1-3DLRH group. There were no significant difference in the number of lymph nodes, the incidence of operative complications, the infection rate, the time of catheterization and the length of hospitalization between the two groups (all P>0.05). The long-term bladder function was evaluated at the twelfth month after operation, 39 patients in the C1-3DLRH group and 53 patients in the C1-2DLRH group were completed the survey. The results showed that 13% (5/39) of the patients in the C1-3DLRH group had long-term bladder dysfunction, which was lower than that 21% (11/53) of the C1-2DLRH group, but there was no significant difference between the two groups (χ(2)=0.980, P=0.322). (2) A total of 251 laparoscopic surgeons questionnaires were eligible. The incidence of side effects in the first and second generation of 3D and 2D laparoscopic surgeons was 20.4% (10/49), 6.9% (6/87) and 3.5% (4/115), respectively. The incidence of side effects in the first generation of 3D laparoscopic surgeons was higher than that in the second generation of 3D (χ(2)=5.463, P=0.019) and 2D laparoscopic surgeons (χ(2)=12.475, P<0.01). There was no difference between the second generation of 3D and 2D laparoscopic surgeons (χ(2)=1.208, P=0.272). Conclusions: 3D laparoscopy is advantageous to the preservation of autonomic nerve in C1-LRH operation and may improve the quality of operation compared with 2D laparoscopy. The second generation of 3D laparoscopic device might overcome the side effects of the surgeons.

Flaxseed extract induces apoptosis in human breast cancer MCF-7 cells

Significant evidence indicated that flaxseed (Linum usitatissimum) possesses various positive health aspects such as reducing the risk of cancer and cardiovascular diseases. The fatty acids are considered to be responsible for these benefits of flaxseed. Herein, the in vitro effects of flaxseed extract on the growth and apoptosis of human breast cancer MCF-7 cells were investigated. The MCF-7 cells treated with flaxseed extract showed a dose-dependent decrease in cell viability. The flaxseed extract induced reactive oxygen species and the flow cytometric analysis demonstrated that flaxseed fatty acids triggered apoptosis of MCF-7 cells, which was also shown by the loss of mitochondrial membrane potential and caspase cascade reaction. Thus, the flaxseed extract regulated the growth of MCF-7 cells and induced apoptosis. Eventually, the flaxseed could be used as a dietary supplement to prevent breast cancer.

[Effect of serum HGF and CK18 in patients with laryngeal cancer on postoperative prognosis]

Objective: To investigate the correlation between the levels of serum cytokeratin 18 (CK18) and hepatocyte growth factor (HGF) and tumor stage and prognosis in patients with laryngeal carcinoma. Method: Patients with laryngeal cancer who were admitted to our hospital from January 2012 to December 2013 were enrolled. Blood samples were collected for CK18 and HGF detection, and postoperative prognosis data were collected at regular follow-up. Result: The serum CK18 and HGF concentration of patients with poorly differentiated tumor, high tumor grade and clinical stage were significantly higher than those with well differentiated tumor, low tumor grade and low clinical stage (P<0.05). The 5-year survival rate (69.9%) of patients with laryngeal cancer in the high CK18 group was significantly lower than that in the low CK18 group (92.3%) (P<0.05), and the 5-year survival rate (71.1%) of patients with laryngeal cancer in the high HGF group was significantly lower than that in the low HGF group (94.2%) (P<0.05). The results of univariate analysis showed that tumor type, differentiation, T grade, N grade and clinical stage affected the survival rate of patients with laryngeal cancer. Cox regression model analysis showed high CK18 and high HGF levels were risk factors for poor prognosis ［CK18 HR: 2.594 (1.558-4.318); P<0.001, HGF HR: 2.671 (1.605-4.446); P<0.001］. Conclusion:The results suggested that serum CK18 and HGF levels can be used as prognostic and disease monitoring biomarkers for laryngeal cancer.