Tannic acid inhibits Escherichia coli biofilm formation and underlying molecular mechanisms: Biofilm regulator CsgD

Biofilms often engender persistent infections, heightened antibiotic resistance, and the recurrence of infections. Therefor, infections related to bacterial biofilms are often chronic and pose challenges in terms of treatment. The main transcription regulatory factor, CsgD, activates csgABC-encoded curli to participate in the composition of extracellular matrix, which is an important skeleton for biofilm development in enterobacteriaceae. In our previous study, a wide range of natural bioactive compounds that exhibit strong affinity to CsgD were screened and identified via molecular docking. Tannic acid (TA) was subsequently chosen, based on its potent biofilm inhibition effect as observed in crystal violet staining. Therefore, the aim of this study was to investigate the specific effects of TA on the biofilm formation of clinically isolated Escherichia coli (E. coli). Results demonstrated a significant inhibition of E. coli Ec032 biofilm formation by TA, while not substantially affecting the biofilm of the ΔcsgD strain. Moreover, deletion of the csgD gene led to a reduction in Ec032 biofilm formation, alongside diminished bacterial motility and curli synthesis inhibition. Transcriptomic analysis and RT-qPCR revealed that TA repressed genes associated with the csg operon and other biofilm-related genes. In conclusion, our results suggest that CsgD is one of the key targets for TA to inhibit E. coli biofilm formation. This work preliminarily elucidates the molecular mechanisms of TA inhibiting E. coli biofilm formation, which could provide a lead structure for the development of future antibiofilm drugs.

Porcine cis-acting lnc-CAST positively regulates CXCL8 expression through histone H3K27ac

The chemokine CXCL8, also known as the neutrophil chemotactic factor, plays a crucial role in mediating inflammatory responses and managing cellular immune reactions during viral infections. Porcine reproductive and respiratory syndrome virus (PRRSV) primarily infects pulmonary alveolar macrophages (PAMs), leading to acute pulmonary infections. In this study, we explored a novel long non-coding RNA (lncRNA), termed lnc-CAST, situated within the Cxcl8 gene locus. This lncRNA was found to be highly expressed in porcine macrophages. We observed that both lnc-CAST and CXCL8 were significantly upregulated in PAMs following PRRSV infection, and after treatments with lipopolysaccharide (LPS) or lipoteichoic acid (LTA). Furthermore, we noticed a concurrent upregulation of lnc-CAST and CXCL8 expression in lungs of PRRSV-infected pigs. We then determined that lnc-CAST positively influenced CXCL8 expression in PAMs. Overexpression of lnc-CAST led to an increase in CXCL8 production, which in turn enhanced the migration of epithelial cells and the recruitment of neutrophils. Conversely, inhibiting lnc-CAST expression resulted in reduced CXCL8 production in PAMs, leading to decreased migration levels of epithelial cells and neutrophils. From a mechanistic perspective, we found that lnc-CAST, localized in the nucleus, facilitated the enrichment of histone H3K27ac in CXCL8 promoter region, thereby stimulating CXCL8 transcription in a cis-regulatory manner. In conclusion, our study underscores the pivotal critical role of lnc-CAST in regulating CXCL8 production, offering valuable insights into chemokine regulation and lung damage during PRRSV infection.

CircNRCAM up-regulates NRCAM to promote papillary thyroid carcinoma progression

PURPOSE

Papillary Thyroid Carcinoma (PTC) is the most prevalent subtype of Thyroid Carcinoma (THCA), a type of malignancy in the endocrine system. According to prior studies, Neural Cell Adhesion Molecule (NRCAM) has been found to be up-regulated in PTC and stimulates the proliferation and migration of PTC cells. However, the specific mechanism of NRCAM in PTC cells is not yet fully understood. Consequently, this study aimed to investigate the underlying mechanism of NRCAM in PTC cells, the findings of which could provide new insights for the development of potential treatment targets for PTC.

METHODS AND RESULTS

Bioinformatics tools were utilized and a series of experiments were conducted, including Western blot, colony formation, and dual-luciferase reporter assays. The data collected indicated that NRCAM was overexpressed in THCA tissues and PTC cells. Circular RNA NRCAM (circNRCAM) was found to be highly expressed in PTC cells and to positively regulate NRCAM expression. Through loss-of-function assays, both circNRCAM and NRCAM were shown to promote the proliferation, invasion, and migration of PTC cells. Mechanistically, this study confirmed that precursor microRNA-506 (pre-miR-506) could bind with m6A demethylase AlkB Homolog 5 (ALKBH5), leading to its m6A demethylation. It was also discovered that circNRCAM could competitively bind to ALKBH5, which restrained miR-506-3p expression and promoted NRCAM expression.

CONCLUSION

In summary, circNRCAM could up-regulate NRCAM by down-regulating miR-506-3p, thereby enhancing the biological behaviors of PTC cells.

[Progress in correlation between lymph node metastasis and prognosis of esophageal cancer]

The status of lymph node metastasis is an important parameter affecting the survival of patients with esophageal carcinoma, which is primarily determined by histological type and the depth of invasion. However, affected by pathological features, heterogeneity and individual differences of tumors, the present staging system of lymph node in esophageal carcinoma has not been unified, the rule of lymph node metastasis remains unclear, and the extent of lymphadenectomy is still controversial. Current lymph node staging system for esophageal carcinoma may be not effective enough, which may lead to inaccurate assessment of the stage and affect the clinicians' choice of treatment modalities, or even affect the conclusions of clinical trials. Therefore, it is essential to optimize the current lymph node staging system for esophageal carcinoma to guide the surgery-based multidisciplinary treatment, and effectively to evaluate the therapeutic effects and predict patients' prognosis.

[Myocardial protection of del Nido cardioplegia in adult cardiac and major vascular surgery with long aortic cross-clamp time]

Objective: To explore the safety and myocardial protection efficacy of del Nido cardioplegia in adult cardiac and major vascular surgery with long aortic cross-clamp (ACC) time. Methods: A total of 2 536 patients who underwent adult cardiac and major vascular surgery with ACC time>90 min at Beijing Anzhen Hospital from March 2018 to March 2023 were collected. The patients were divided into two groups according to the type of cardioplegia solution: the del Nido cardioplegia solution group (DC group) and the cold blood cardioplegia solution group (BC group). Preoperative baseline data of the patients (age, gender, comorbidities, ejection fraction, etc) were adjusted using propensity score matching (PSM). Cardiopulmonary bypass (CPB) time, ACC time, total amount of cardioplegia solution, in-hospital mortality rate, length of intensive care unit (ICU) stay, mechanical ventilation time, postoperative complications, left ventricular ejection fraction, and troponin levels were compared between the two groups. Results: After PSM, a total of 306 patients were included, including 223 males and 83 females, with a mean age of (52.0±12.3) years. There were 153 cases in the DC group and 153 cases in the BC group. Compared with the DC group, the cross-clamp time was longer [109(100, 150) min vs 102(91, 133) min, P<0.001], the rate of return to spontaneous rhythm was lower [51.6% (79/153) vs 86.9%(133/153), P<0.001], and intraoperative peak glucose was higher [12.6 (6.5, 15.9) mmol/L vs 10.1 (8.5, 12.4) mmol/L, P=0.005] in the BC group. In addition, perioperative mortality [4.6% (7/153) vs 3.3% (5/153), P=0.132], stroke[3.9% (6/153) vs 3.3% (5/153), P=0.759], renal insufficiency [3.3% (5/153) vs 6.5% (10/153), P=0.186], atrial fibrillation [4.6% (7/153) vs 2.6% (4/153), P=0.652] and low cardiac output syndrome [3.9% (6/153) vs 4.6% (7/153), P=0.716] did not differ between the two groups. Compared with BC group, DC group had lower level of high sensitivity troponin (hsTnI) [1.2 (0.8, 1.8) μg/L vs 1.3 (0.9, 2.3) μg/L, P=0.030] and creatine kinase isoenzyme (CK-MB) [31.0 (20.0, 48.9) μg/L vs 37.0 (24.0, 58.9) μg/L, P=0.011] at 24 h postoperatively, and shorter length of ICU stay [35.6 (19.8, 60.5) h vs 42.6 (21.9, 83.6) h, P=0.015] and mechanical ventilation time [20.5 (15.5, 41.0) h vs 31.5 (17.1, 56.0) h, P=0.012]. Subgroup analysis showed that in the 120-180 minute subgroup, patients in the DC group had a shorter cross-clamp time [132 (124, 135) min vs 136 (124, 138) min, P<0.001], while levels of hsTnI [1.6 (1.1, 2.0) μg/L vs 1.4 (1.0, 2.6) μg/L, P=0.030] and CK-MB [38.8 (23.5, 55.5) μg/L vs 37.0 (24.5, 62.3) μg/L, P=0.011] were higher than those in the BC group. Conclusions: In adult cardiac and major vascular surgery with ACC times>90 min, comparable myocardial protection is observed with the use of DC compared with BC. Additional advantages in glycemic control, return to spontaneous rhythm, and improved surgical procedures make DN an attractive alternative for myocardial protection in adult cardiac surgery.

Molecular Detection and Genetic Characterization of Vertically Transmitted Viruses in Ducks

To investigate the distribution and genetic variation in four vertically transmitted duck pathogens, including duck hepatitis B virus (DHBV), duck circovirus (DuCV), duck hepatitis A virus 3 (DHAV-3), and avian reoviruses (ARV), we conducted an epidemiology study using PCR and RT-PCR assays on a duck population. We found that DHBV was the most prevalent virus (69.74%), followed by DuCV (39.48%), and then ARV (19.92%) and DHAV-3 (8.49%). Among the 271 duck samples, two, three or four viruses were detected in the same samples, indicating that the coinfection of vertical transmission agents is common in ducks. The genetic analysis results showed that all four identified DuCV strains belonged to genotype 1, the DHAV-3 strain was closely clustered with previously identified strains from China, and the ARV stain was clustered under genotype 1. These indicate that different viral strains are circulating among the ducks. Our findings will improve the knowledge of the evolution of DuCV, DHAV-3, and ARV, and help choose suitable strains for vaccination.

Impact of CRAMP-34 on Pseudomonas aeruginosa biofilms and extracellular metabolites

Biofilm is a structured community of bacteria encased within a self-produced extracellular matrix. When bacteria form biofilms, they undergo a phenotypic shift that enhances their resistance to antimicrobial agents. Consequently, inducing the transition of biofilm bacteria to the planktonic state may offer a viable approach for addressing infections associated with biofilms. Our previous study has shown that the mouse antimicrobial peptide CRAMP-34 can disperse Pseudomonas aeruginosa (P. aeruginosa) biofilm, and the potential mechanism of CRAMP-34 eradicate P. aeruginosa biofilms was also investigated by combined omics. However, changes in bacterial extracellular metabolism have not been identified. To further explore the mechanism by which CRAMP-34 disperses biofilm, this study analyzed its effects on the extracellular metabolites of biofilm cells via metabolomics. The results demonstrated that a total of 258 significantly different metabolites were detected in the untargeted metabolomics, of which 73 were downregulated and 185 were upregulated. Pathway enrichment analysis of differential metabolites revealed that metabolic pathways are mainly related to the biosynthesis and metabolism of amino acids, and it also suggested that CRAMP-34 may alter the sensitivity of biofilm bacteria to antibiotics. Subsequently, it was confirmed that the combination of CRAMP-34 with vancomycin and colistin had a synergistic effect on dispersed cells. These results, along with our previous findings, suggest that CRAMP-34 may promote the transition of PAO1 bacteria from the biofilm state to the planktonic state by upregulating the extracellular glutamate and succinate metabolism and eventually leading to the dispersal of biofilm. In addition, increased extracellular metabolites of myoinositol, palmitic acid and oleic acid may enhance the susceptibility of the dispersed bacteria to the antibiotics colistin and vancomycin. CRAMP-34 also delayed the development of bacterial resistance to colistin and ciprofloxacin. These results suggest the promising development of CRAMP-34 in combination with antibiotics as a potential candidate to provide a novel therapeutic approach for the prevention and treatment of biofilm-associated infections.

Molecular characterization and pathogenicity evaluation of enterovirus G isolated from diarrheic piglets

IMPORTANCE

Enterovirus G is a species of positive-sense single-stranded RNA viruses associated with several mammalian diseases. The porcine enterovirus strains isolated here were chimeric viruses with the PLCP gene of porcine torovirus, which grouped together with global EV-G1 strains. The isolated EV-G strain could infect various cell types from different species, suggesting its potential cross-species infection risk. Animal experiment showed the pathogenic ability of the isolated EV-G to piglets. Additionally, the EV-Gs were widely distributed in the swine herds. Our findings suggest that EV-G may have evolved a novel mechanism for broad tropism, which has important implications for disease control and prevention.

Safety and Efficacy Analysis of Patients with Extensive-Stage Small Cell Lung Cancer (ES-SCLC) Treated with SHR-1316 Plus Chemotherapy and Sequential Chest Radiotherapy as First-Line Therapy from a Phase II Trial

PURPOSE/OBJECTIVE(S)

CAPSTONE-1, a phase 3 trial, showed that SHR-1316 (PD-L1 antibody) combined with standard first-line chemotherapy could prolong overall survival (OS) in patients (pts) with ES-SCLC. The CREST trial reported consolidative thoracic radiotherapy (TRT) of 30 Gy in 10 fractions provided a 10% 2-year OS benefit and more intensive TRT should be investigated in ES-SCLC. In the era of immunotherapy, the role of TRT also needs further exploration. Therefore, we designed this clinical trial to investigate the efficacy and safety of SHR-1316 plus first-line chemotherapy followed by TRT combined with SHR-1316.

MATERIALS/METHODS

Key inclusion criteria were pts aged 18-75 years, with previously untreated histologically or cytologically confirmed ES-SCLC, and an ECOG performance status of 0-1. Eligible pts would receive 4∼6 cycles of SHR-1316 (20mg/kg, D1, q3w) combined with EP/EC (etoposide, 100mg/m2, D1-5, q3w and cisplatin, 75mg/m², D1-3, q3w or carboplatin, AUC = 5, D1, q3w), followed by SHR-1316 combined with TRT (≥3 Gy*10 f or ≥2 Gy*25 f, involved-field irradiation), and then the maintenance therapy with SHR-1316 until disease progression or intolerable adverse events (AEs). The main endpoints included ORR, PFS and safety.

RESULTS

From October 2020 to January 2023, 33 pts received SHR-1316 and sequential consolidative TRT. Among them, 19 pts received high-dose TRT (>3 Gy*10 f or ≥2 Gy*25 f) and 14 pts received low-dose TRT (≤3 Gy*10 f or<2 Gy*25 f). The median age was 62 (range: 38-73). Most pts were male (28, 84.8%), former smokers (22, 66.7%) with an ECOG performance status 1 (32, 97%). Ten (30.3%) pts were diagnosed with brain metastasis and 10 (30.3%) pts had liver metastasis at baseline. At the data cutoff date, 9 pts remained on treatment, the average number of treatment cycles was 9.2. 33 pts had at least one 1 post-treatment tumor assessment. The confirmed ORR and DCR were 90.9% (30/33) and 100% (33/33) in all pts, were 89.5% (17/19) and 100% (19/19) in high-dose TRT group, and were 92.9% (13/14) and 100% (14/14) in low-dose TRT group. The median PFS was 10.2(CI: 5.8∼14.7) months in all pts, was 7 (CI: 3.8∼10.2) months in high-dose TRT group and 10.4 (CI: 8.4∼12.3) months in low-dose TRT group. AEs occurred in 27 (81.8%) pts and grade 3 or 4 AEs occurred in 20 (60.6%) pts. The most common grade 3 or 4 AEs included neutropenia (15, 45.5%), leukopenia (8, 24.2%), lymphocytopenia (5, 15.2%), pneumonia (3, 9.1%), anemia (3, 9.1%) and thrombocytopenia (2, 6.1%).

CONCLUSION

SHR-1316 plus chemotherapy and sequential TRT as first-line therapy for ES-SCLC showed promising efficacy and acceptable safety. There is no significant difference between high-dose and low-dose TRT groups in terms of safety and efficacy according to current data.

A non-toxic recombinant Clostridium septicum α toxin induces protective immunity in mice and rabbits

Clostridium septicum alpha toxin (CSA) plays significant roles in ruminant's braxy. Genetically engineered CSA has been shown to function as a potential vaccine candidate in the prevention of the disease caused by Clostridium septicum. In the present study, we synthesized a non-toxic recombinant, rCSAm4/TMD by introducing four amino acid substitutions (C86L/N296A/H301A/W342A) and 11-amino-acid deletion (residues 212 to 222). Compared to recombinant CSA, rCSAm4/TMD showed no cytotoxicity to MDCK cells and was not fatal to mice. Moreover, rCSAm4/TMD could protect immunized mice against 5 × mouse LD100 (100% lethal dose) of crude CSA without obvious pathological change. Most importantly, rabbits immunized with rCSAm4/TMD produced high titers of neutralizing antibodies which protected the rabbits against crude CSA challenge. These data suggest that genetically detoxified rCSAm4/TMD is a potential subunit vaccine candidate against braxy.

[Current application and limitations of augmented reality in the stomatology]

Computer-assisted technology are gradually integrated into dental education and clinical treatment. As a cutting-edge technology in computer-aided medicine, augmented reality can not only be used as an aid to dental education by presenting three-dimensional scenes for teaching demonstration and experimental skills training, but also can superimpose virtual image information of patients onto real lesion areas for real-time feedback and intraoperative navigation. This review explores the current applications and limitations of augmented reality in dentistry to provide a reference for future research.

[Protective effect of anti-idiopathic pulmonary fibrosis drug Pirfenidone and Sufenidone (SC1011) on pulmonary injury induced by tuberculosis in a mouse tuberculosis model]

Objective: To evaluate the protective effect of anti-idiopathic pulmonary fibrosis (IPF) marketed drug Pirfenidone and its clinical drug Sufenidone (SC1011) against lung injury in a mouse tuberculosis model. Methods: C57BL/6 mouse model of tuberculosis was established. A total of 75 C57BL/6 mice were infected with 1×10⁷ CFU/ml H37Rv suspension by aerosol and randomly divided into untreated (n=9) group, isoniazid+rifampicin+pyrazinamide (HRZ) group (n=22), PFD+HRZ group (n=22), and SC1011+HRZ group (n=22). C57BL/6 mice were infected with H37Rv by aerosol for 6 weeks and then treated. Seven mice in each treatment group were weighed, sacrificed, dissected and observed for lung and spleen lesions at 4 and 8 weeks of treatment. HE staining and Masson staining were used to assess degree of lung injury and fibrosis, respectively. ELISA was used to assess the IFN-γ/TNF-α content in the serum of mice in each treatment group after 4 weeks of treatment. Hydroxyproline (HYP) content in lung tissue was measured by alkaline hydrolysis; meanwhile, CFU counts were used to assess the bacterial load in the lung and spleen of mice in each treatment group and the recurrence of spleen and lung tissue after 12 weeks of drug withdrawal. Results: At 8 weeks, the HYP content in the lung tissue was (630±58), (635±17), and (840±70) μg/mg in the PFD+HRZ, SC1011+HRZ, and HRZ treatment group, respectively (P<0.05).At 8 weeks, the proportion of Masson staining blue-stained area, that was, positive area, in lung tissue was 16.65%±1.82%, 10.01%±2.16%, and 21.36%±3.21%, respectively (F=27.11, P<0.001).The lung injury scores by HE staining at 8 weeks were (5.00±0.50), (5.00±0.47), and (6.89±0.99) points, respectively (F=19.81, P<0.001).The results of 4-week ELISA showed that the levels of TNF-α and IFN-γ in the serum of the SC1011+HRZ-treated group were lower than those of the HRZ-treated group (all P<0.05).The degree of lung injury and fibrosis in PFD+HRZ and SC1011+HRZ treatment groups were lower than those in HRZ treatment group (all P<0.001). The number of viable bacteria in the lung tissue of mice treated with PFD+HRZ, SC1011+HRZ, and HRZ for 4 weeks was lower than that of mice untreated [(1.82±0.10), (1.91±0.05), (1.79±0.17) vs. (5.27±0.07) lg(CFU+1)/ml, all P<0.05)]. And the aseptic transformation of the spleen of mice was achieved in each treatment group at 8 weeks of administration. After 12 weeks of drug withdrawal, the recurrence of lung infection in the SC1011+HRZ treatment group was 3/7 lower than 5/7 in the HRZ treatment group (P>0.05); the recurrence of spleen infection in the SC1011+HRZ treatment group was 1/7 lower than 5/7 in the HRZ treatment group (P>0.05).Pulmonary infection recurred more frequently in PFD+HRZ 6/7 versus HRZ 5/7 (P>0.05). Conclusions: PFD/SC1011, when combined with HRZ, reduced lung injury and reduced secondary fibrosis in pulmonary tuberculosis in C57BL/6 mice. SC1011 combined with HRZ has no significant short-term therapeutic effect on MTB, but may reduce its recurrence rate in long-term treatment, especially in reducing the recurrence rate of mouse spleen.

Apabetalone, a BET inhibitor, attenuates inflammation induced by viral RNA mimetic and reduces SARS-CoV-2 spike protein binding regardless of variants

Background/Introduction

Hyperinflammatory responses to SARS-CoV-2 can cause myocarditis and cardiac dysfunction including congestive heart failure [1]. SARS-CoV-2 RNA induces type I interferon (IFN-I), activating IFN regulatory factors (IRFs) and downstream IFN stimulated genes (ISGs) to initiate inflammatory processes. SARS-CoV-2 variants may develop immune escape, undercutting benefits of vaccinations. These challenges highlight the need of variant-independent therapies to improve COVID-19 outcomes. Apabetalone is an epigenetic BD2-selective BET inhibitor in phase 3 trials for cardiovascular disease [2]. Apabetalone has the potential to treat COVID-19. It counters inflammatory signals caused by cytokine storm (CS), preventing cardiac dysfunction associated with severe COVID-19 symptoms in cardiac organoids [3]. It also downregulates angiotensin-converting enzyme 2 (ACE2) expression, the main host cell receptor for SARS-CoV-2 spike protein thus impeding propagation of wild-type SARS-CoV-2 [3,4].

Purpose

1) Evaluate apabetalone's effect on inflammatory processes induced by viral-RNA mimetic in human lung cells; 2) Assess apabetalone's ability to prevent binding of the highly contagious delta variant spike protein to human lung cells.

Methods

Inflammatory gene expression was examined by real-time PCR in apabetalone treated human bronchial epithelial cells (Calu-3) stimulated with poly I:C, a well-accepted viral RNA mimetic that elicits inflammatory signals similar to SARS-CoV-2 RNA [5]. Binding of SARS-CoV-2 delta or wild-type spike protein to apabetalone treated Calu-3 cells was determined by flow cytometry.

Results

In Calu-3 cells, apabetalone dose-dependently downregulated poly I:C induced transcription of key COVID-19 associated cytokines (IL6, CXCL10, CCL2) to a similar extent as baricitinib (up to 86%, p&lt;0.0001), an anti-inflammatory agent in emergency use for COVID-19 treatment. Moreover, apabetalone but not baricitinib diminished IL1B mRNA levels (up to 66%, p&lt;0.0001). Apabetalone and baricitinib opposed poly I:C induced expression of IFNB1 (an IFN-I), IRF1 and IRF9 (upstream regulators) as well as IFIT1 and IFIT2 (downstream ISGs that regulate CXCL10 expression; up to 90%, p&lt;0.0001). Clinically relevant doses of apabetalone did not alter expression of anti-viral IFITM2, an ISG that blocks SARS-CoV-2, particularly omicron, endosomal entry [6]. Therefore, apabetalone counters the expression of inflammatory factors with roles in CS and IFN-I signaling in response to poly I:C. Additionally, apabetalone reduced delta and wild-type spike protein binding to unstimulated Calu-3 cells (up to 72%, p&lt;0.0001).

Conclusions

Apabetalone's dual anti-viral and anti-inflammatory mechanism positions it as a variant-independent COVID-19 therapeutic. Together with an established safety profile from &gt;2000 treatment-years with apabetalone, the data provide rationale for an ongoing clinical trial (NCT04894266) which includes analysis of cardiac damage.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Resverlogix Corp

[The concept of traditional chinese medicine:history, theory and empirical research]

The concept of traditional Chinese medicine has different connotations and extensions in different historical periods. This paper examines the formation and development of the concept of traditional Chinese medicine in the perspective of history, theory and empirical research, and explores the internal connection among different medical systems and between medicine and other disciplines. It attempts to re-define the connotation and extension of the concept of traditional Chinese medicine in the context of the new era, provide references for building the medical community of the Chinese nation and promote the standardization of Chinese medicine terminology, advance the cross-disciplinary construction and establishing a new medical system with the characteristics of openness and tolerance, in order to provide the solution, wisdom and power of traditional Chinese medicine for global health in the process of building a community of human health.

Identification of Mycobacterium avium subspecies paratuberculosis in sheep farms in Bayannaoer, Inner Mongolia, China (short communication)

BACKGROUND

Paratuberculosis is a widespread chronic infection of Mycobacterium avium subspecies paratuberculosis (MAP) that causes significant economic losses to the sheep industry. The current study investigated this disease, which causes diarrhea in sheep, particularly, in Bayannaoer, Inner Mongolia, China. Diagnosis was based on clinical symptoms, pathological autopsy, histopathological inspection, and serological and molecular methods.

RESULTS

MAP was confirmed using polymerase chain reaction using DNA extracted from tissue and fecal samples. Serum samples from 472 individual sheep were obtained to detect antibodies against MAP using an enzyme-linked immunosorbent assay. MAP antibodies were separately detected in 17.86% (35/196) and 18.48% (51/276) of sheep herds at approximately 6 months and ≥ 1 year of age, respectively. The tissue lesion and pathological section results were consistent with paratuberculosis infection.

CONCLUSIONS

To our knowledge, this is the first report of Mycobacterium avium subspecies paratuberculosis seroprevalence in Bayannaoer sheep in Inner Mongolia. Our findings show that MAP is not only prevalent, but also a potential threat to this region. Further investigations, including long-term epidemiological surveillance and isolation are needed for the awareness and effective treatment of paratuberculosis in sheep of Inner Mongolia.

[Study on the pharmacodynamic activity of combinations with the new anti-tuberculosis drug pyrifazimine in vitro and in vivo in mouse]

Objective: To evaluate two-drug combination interaction between pyrifazimine(TBI-166) and anti-drug-resistant tuberculosis group A drugs Bedaquiline (BDQ), Moxifloxacin (MFX) and the new anti-tuberculosis drug Delamanid (DLM), SQ109, Q203, and PBTZ169 in vitro and in vivo in mouse, so as to provide basis for TBI-166 combination therapy. Methods: This study was performed from September 2020 to July 2021. The chessboard method was used to evaluate the interaction between TBI-166 and BDQ, MFX, DLM, SQ109, and PBTZ169. The time-killing kinetics method was used to evaluate the anti-tuberculosis activity of the two-drug combination with partial synergy. The BALB/c mouse acute infection model was used to evaluate the anti-tuberculosis activity at 4 and 8 weeks in the two-drug combination group (TBI-166+BDQ, TBI-166+SQ109, TBI-166+PBTZ169, TBI-166+Q203) and monotherapy groups (TBI-166, BDQ, SQ109, PBTZ169, Q203). Data analysis was performed using an independent sample t-test. Results: After TBI-166 combined with anti-tuberculosis drugs, MIC was reduced to 6.25% to 25.00% of TBI-166 monotherapy. After TBI-166 combined with BDQ, SQ109 and PBTZ169, the partial inhibitory concentration index (FICI) values were 0.53, 0.75 and 0.75, respectively; the time sterilization experiment showed that the viable population of Mycobacterium tuberculosis treated with two-drug combination of TBI-166 and BDQ, SQ109, PBTZ169 for 14 days decreased at least 3 log₁₀ CFU/ml. In the mouse experiments, it was found that, the amount of viable bacteria in lung tissue of BDQ, SQ109 and PBTZ169 combined with TBI-166 groups was lower than that of the monotherapy group,respectively. The lung tissue culture of mice in the TBI-166+BDQ group was negative after 4 weeks of treatment, and the number of live bacteria in the lungs of the TBI-166+BDQ group was 1.49 log₁₀CFU lower than that of the BDQ monotherapy group(P<0.01). Conclusion: In vitro and in vivo experiments in mice revealed that TBI-166 had synergistic anti-tuberculosis activity after being combined with BDQ, SQ109 and PBTZ169, respectively.

Molecular Detection and Genetic Characterization of Potential Zoonotic Swine Enteric Viruses in Northern China

Despite significant economic and public health implications, swine enteric viruses that do not manifest clinical symptoms are often overlooked, and data on their epidemiology and pathogenesis are still scarce. Here, an epidemiological study was carried out by using reverse transcription-polymerase chain reaction (RT-PCR) and sequence analysis in order to better understand the distribution and genetic diversity of porcine astrovirus (PAstV), porcine encephalomyocarditis virus (EMCV), porcine kobuvirus (PKV), and porcine sapovirus (PSaV) in healthy pigs reared under specific pathogen-free (SPF) or conventional farms. PKV was the most prevalent virus (51.1%, 247/483), followed by PAstV (35.4%, 171/483), then PSaV (18.4%, 89/483), and EMCV (8.7%, 42/483). Overall, at least one viral agent was detected in 300 out of 483 samples. Out of the 300 samples, 54.0% (162/300), 13.0% (39/300), or 1.0% (3/300) were found coinfected by two, three, or four viruses, respectively. To our knowledge, this is the first report of EMCV detection from porcine fecal samples in China. Phylogenetic analysis revealed genetically diverse strains of PAstV, PKV, and PSaV circulating in conventional and SPF farms. Detection of swine enteric viruses with a high coinfection rate in healthy pigs highlights the importance of continuous viral surveillance to minimize future economic and public health risks.

[Attention should be paid to accurate pathological diagnosis of breast cancer]

Breast cancer has replaced lung cancer as the most common malignant tumor in the world. Precise surgical, internal medicine, targeted, radiotherapy, immunotherapy and other treatment methods will improve the survival and quality of life of patients. Accurate pathological diagnosis is the prerequisite and key to achieve clinical accurate treatment. This article makes a review of the relevant content of different submitted specimens and precise pathological diagnosis of breast cancer.

[Efficacy and safety of endothelin receptor antagonists combined with phosphodiesterase 5 inhibitor in the treatment of pulmonary arterial hypertension: a network meta-analysis]

Objective: To examine the efficacy and safety of endothelin receptor antagonists (ERA) combined with phosphodiesterase 5 inhibitors (PDE5i) in the treatment of pulmonary artery hypertension (PAH). Methods: Computer-based retrieval was performed on PubMed, Cochrane Library, CNKI, Wanfang, and VIP database (up to February 12th, 2021). Randomized controlled trials about endothelin receptor antagonists (ERAs) or PDE5i in patients with PAH were collected. The change of 6-minute walking distance (6MWD) in 12-16 weeks was used as primary outcome index. Case fatality rate, worsening clinical events, WHO functional class (FC) improvement, adverse events (AEs), serious adverse events (SAE) were the key secondary outcomes indicators. STATA 16.0 software was used for network meta-analysis, and the pooled estimates of odds ratios (ORs) or weighted mean differences (WMDs) and 95% confidence intervals (CIs) of the results were shown. To help explain ORs and WMDs, we used the surface under the cumulative ranking curve (SUCRA) to calculate the probability of each intervention. Results: We included 29 trials with 5 949 participants. In network meta-analysis, Bosentan combined with Sildenafil (WMD=53.93, 95%CI=6.19-101.66) had shown the greatest improvement in 6MWD compared with placebo, followed by Bosentan combined with Tadalafil (WMD=50.84, 95%CI=7.05-94.62), Ambrisentan combined with Tadalafil (WMD=46.67, 95%CI=15.88-77.45), Bosentan (WMD=29.44, 95%CI=5.86-53.02), Ambrisentan (WMD=23.90, 95%CI=0.31-47.48) and Macitentan (WMD=21.57, 95%CI=2.45-40.69). According to SUCRA, the effects of different intervention measures on improving 6MWD in patients with arterial pulmonary hypertension were as follows: Bosentan+Sildenafil (82.9%)>Bosentan+Tadalafil (78.4%)>Ambrisentan+Tadalafil (77.1%)>Bosentan (49.2%)>Sildenafil (48.5%)>Ambrisentan (40.3%)>Macitentan (37.3%)>Tadalafil (33.0%)>Placebo (3.3%). For the WHO functional class, Sildenafil (OR=2.90, 95%CI=1.04-8.08) was optimal compared with placebo, followed by Bosentan (OR=2.15, 95%CI=1.15-4.04), and there was no significant difference in the rest. For clinical worsening, Bosentan combined with Tadalafil (OR=0.08, 95%CI=0.01-0.49) performed best compared with placebo, followed by Bosentan (OR=0.20, 95%CI=0.11-0.38), Bosentan combined with Sildenafil (OR=0.21, 95%CI=0.09-0.46), Ambrisentan combined with Tadalafil (OR=0.27, 95%CI=0.15-0.50), Sildenafil (OR=0.33, 95%CI=0.17-0.66) and Tadalafil (OR=0.44, 95%CI=0.21-0.90). There was no statistical difference between all interventions and placebo in terms of the incidence of adverse events and serious adverse events. For case fatality rate, Ambrisentan (OR=0.28, 95%CI=0.11-0.74) was statistically superior to placebo and there was no statistics difference in the rest. Conclusions: The combination therapy of ERAs and PDE5i performed well in the short-term improvement of motor function. Furthermore, there was no significant difference with monotherapy in terms of safety. However, it is worth emphasizing that the choice of treatment should be based on the patient's individualized situation and the patient's requirements.

The Utility of PathElective.com as a Curricular Adjunct in Laboratory Medicine Education

Introduction/Objective

PathElective.com was founded as a means of combating stagnating resident and medical student education due to halting of in-person educational activities during the COVID-19 pandemic. The site has since grown to be included in medical student and resident training programs at numerous institutions across the world, serving as a unique means of delivering high-quality and trackable laboratory medicine education.

Methods/Case Report

The PathElective website was developed using Squarespace, video lectures were recorded by each professor or sourced from openly available web resources incorporating virtual slides, reading assignments, or relevant podcasts at the course director’s discretion. Monthly website traffic data were obtained through Squarespace analytics for the first 11 months of the website being available (May 1, 2020, to April 22, 2021). Geographic and source data were obtained through deidentified IP address analysis built-in to Squarespace analytics. Students who registered to take the online courses were assessed before and after interacting with the course materials using a dual form crossover quiz design to prevent memorization of questions and assess comprehension. Quiz data were all anonymous and improvement was determined using a paired t-test. Comparisons between courses were made via percentage improvements.

Results (if a Case Study enter NA)

Over the tracking period, PathElective.com received 352,012 page views, 73,550 visits, 33,225 unique visitors, and accrued 5,815 registered users. Most of the visitors (72.8%) arrived at the site via a direct URL input, 14.9% through a search engine, and 10.6% through social media. Most visitors were from the US (43.8%) or India (11.9%). With a total of 1598 test pairs being analyzed from all clinical pathology modules, the average increase in score was 14.4% (95%, CI=10.3-18.6, p=0.0052). All courses experienced a statistically significant increase in scores except for Clinical Chemistry lesson 3.2 (7%, -1.8-15.9% CI, p=0.12). Courses were well received with a median satisfaction score was very satisfied in all six assessment categories.

Conclusion

PathElective.com is a free and effective means of enhancing clinical pathology training in medical education. Students liked the online format, the quality of the lectures, and course faculty, and felt they could get help if needed. An area of improvement for this platform would be the interaction with students on social media.

Bromodomain and extraterminal (BET) protein inhibitor, apabetalone, reduces ACE2 expression and attenuates SARS-CoV-2 infection in vitro

Background/Introduction

SARS-CoV-2 causes life threatening COVID-19 complications including acute coronary syndrome, venous thromboembolism, hyperinflammation and damage in multiple tissues. The SARS-CoV-2 “spike protein” binds cell surface receptors including angiotensin-converting enzyme 2 (ACE2) for entry into host cells to initiate infection. Host cell dipeptidyl peptidase-4 (DPP4 / CD26) is implicated as a cofactor in uptake. Recent evidence indicates expression of factors involved in SARS-CoV-2 uptake into host cells is regulated by BET proteins, epigenetic readers modulating gene expression. Apabetalone, the most clinically advanced BET inhibitor (BETi), is in phase 3 trials for cardiovascular disease (CVD) (a,b). In cultured human cardiomyocytes, apabetalone suppressed infection with SARS-CoV-2 and prevented dysfunction of cardiac organoids induced by the cytokine-storm that arises in patients with severe symptoms (c). However, anti-viral properties of apabetalone in other cell types are not known.

Purpose

To examine effects of apabetalone on SARS-CoV-2 infection in cell culture via downregulated expression of cell surface receptors involved in viral entry. Cell systems used mimic initial sites of infection in the lung as well as cell types contributing to complications in late stages of infection.

Methods

Gene expression was measured by real-time PCR, protein levels by immunoblot or flow cytometry, and binding of recombinant SARS-CoV-2 spike protein by flow cytometry. Infection with SARS-CoV-2 was determined in a BSL3 facility. Infectivity was quantified by determining levels of viral spike protein amongst total cells via imaging on an Operetta CLS.

Results

In Calu-3, a human bronchial epithelial cell line, apabetalone dose-dependently downregulated ACE2 gene expression (up to 98%), reduced ACE2 protein levels (up to 84%) and diminished binding of SARS-CoV-2 spike protein (up to 77%, p<0.001 for all parameters). Further, apabetalone abolished infection of Calu-3 cells with live SARS-CoV-2, which was comparable to other antiviral agents. Apabetalone-driven ACE2 downregulation was also observed in extrapulmonary cell types including HepG2, Huh-7 or primary hepatocytes (up to 90%, p<0.001 for all cell types), and Vero E6, a monkey kidney epithelial cell line (up to 38%, p<0.05). DPP4/CD26, a potential cofactor for SARS-CoV-2 uptake, was also downregulated by apabetalone in Calu-3 cells (mRNA ∼65% and protein ∼40%, p<0.001), which may be synergistic with ACE2 reductions to impede SARS-CoV-2 infection.

Conclusions

Apabetalone, an investigational drug for CVD, reduced cell surface receptors (ACE2 and DPP4) involved in SARS-CoV-2 uptake into host cells and dramatically attenuated SARS-CoV-2 infection/propagation in vitro. Our results suggest apabetalone can mitigate SARS-CoV-2 replication in multiple organs, which together with an established safety profile supports clinical evaluation of apabetalone to treat

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): COVID-19 Rapid Response Grant from the College of Medicine at the University of Nebraska Medical Center (to DE and SPMR), and by University of Nebraska Medical Center start-up funds (to DE).

LINC01605 regulates proliferation, migration and invasion of colorectal cancer cells via targeting miR-3960/SOX11

OBJECTIVE

We aimed to determine the expression level of long intergenic non-coding ribonucleic acid 1605 (LINC01605) in colorectal cancer (CRC), and to explore the effects of the LINC01605/microRNA (miR)-3960/sex-determining region Y-box 11 (SOX11) regulatory axis on the biological behaviors of CRC cells and the molecular mechanism therein.

PATIENTS AND METHODS

Tissue specimens were collected from 38 patients with CRC, and the relative expression level of LINC01605 in the CRC tissues and CRC cells was measured using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Then, the effects of LINC01605 on the proliferation, apoptosis, invasion and metastasis of CRC cells were observed via in vitro assays [cell counting kit (CCK)-8 assay, flow cytometry and transwell assay]. Besides, the possible miRNAs binding to LINC01605 were predicted by the bioinformatics method, and they were screened and verified using qRT-PCR and Dual-Luciferase reporter gene assay. Finally, the downstream target genes of miR-3960 were predicted by means of bioinformatics, and they were also screened and confirmed via qRT-PCR and Dual-Luciferase reporter gene assay.

RESULTS

According to the results of qRT-PCR, the expression of LINC01605 was up-regulated in 31 out of 38 cases of CRC tissue specimens, and its expression in CRC cells was higher than that in normal colorectal cells. The results of in vitro assays revealed that the proliferation, migration and invasion abilities of CRC cells were weakened, with an increased apoptosis rate after interference with LINC01605 expression. Based on the results of qRT-PCR and Dual-Luciferase reporter gene assay, miR-3960 was the target of LINC01605, while SOX11 was the target of miR-3960. Moreover, the expression of miR-3960 rose, but that of SOX11 declined after interference with LINC01605 expression. It was found through Western blotting that the protein expression of SOX11 was lowered after interference with LINC01605 expression.

CONCLUSIONS

LINC01605 has an up-regulated expression in CRC, and accelerates the proliferation, migration and metastasis of CRC cells by the miR-3960/SOX11 regulatory axis.

Observation of topological superconductivity in a stoichiometric transition metal dichalcogenide 2M-WS2

Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubits for quantum computation. Despite their importance in both fundamental research and applications, natural TSCs are very rare. Here, combining state of the art synchrotron and laser-based angle-resolved photoemission spectroscopy, we investigated a stoichiometric transition metal dichalcogenide (TMD), 2M-WS₂ with a superconducting transition temperature of 8.8 K (the highest among all TMDs in the natural form up to date) and observed distinctive topological surface states (TSSs). Furthermore, in the superconducting state, we found that the TSSs acquired a nodeless superconducting gap with similar magnitude as that of the bulk states. These discoveries not only evidence 2M-WS₂ as an intrinsic TSC without the need of sensitive composition tuning or sophisticated heterostructures fabrication, but also provide an ideal platform for device applications thanks to its van der Waals layered structure.

Adaptability of winter wheat Dongnongdongmai 1 (Triticum aestivum L.) to overwintering in alpine regions

Long winters led to a one-crop-a-year cultivation system until the winter wheat Dongnongdongmai 1 (Dn1) was successfully cultivated in northeast China. This crop variety is resistant to extremely low temperatures (-35 °C). To better understand the adaptability of winter wheat Dn1 to low temperatures, gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and metabolomics analysis was conducted on the tillering nodes of winter wheat during the overwintering period. Enzyme-regulating genes of the metabolic products were also quantitatively analysed. The metabolomic results for the tillering nodes in the overwintering period showed that disaccharides had a strong protective effect on winter wheat Dn1. Amino acid metabolism (i.e. proline, alanine and GABA) changed significantly throughout the whole wintering process, whereas organic fatty acid metabolism changed significantly only in the late stage of overwintering. This result indicates that the metabolites used by winter wheat Dn1 differ in different overwintering stages. The relationship between field temperature and metabolite changes in winter wheat Dn1 during overwintering periods is discussed, and disaccharides were identified as the osmotic stress regulators for winter wheat Dn1 during the overwintering process, as well as maintenance of the carbon and nitrogen balance by monosaccharides, amino acids and lipids for cold resistance.

[Effect of long non-coding RNA MBNL1-AS1 expression on prognosis of acute myeloid leukemia patients]

Objective: To explore the prognosis effect of the expression of long-chain non-coding RNA (lncRNA) MBNL1-AS1 on acute myeloid leukemia (AML) patients. Methods: One hundred and twenty-five AML patients of the Cancer Genome Atlas (TCGA) from November 2001 to March 2010 were involved, including 70 patients who received chemotherapy only and other 55 patients treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT) in addition to chemotherapy. According to the median expression of lncRNA MBNL1-AS1, patients of chemotherapy group were divided into high expression sub-group(n=35) and low expression sub-group (n=35), and patients of allo-HSCT group were also divided into high expression sub-group (n=28) and low expression sub-group (n=27) for prognosis analysis. Clinical characteristics at diagnosis, including peripheral white blood cell counts (WBC), blast percentages in peripheral blood and bone marrow (BM), French-American-British (FAB) subtypes and the frequencies of common genetic mutations in AML were described. The event-free survival (EFS) rate and overall survival (OS) rate of patients in different groups were analyzed, and the influence of the clinical characteristics of patients on the prognosis of AML was analyzed by COX multivariate analysis. Results: In the chemotherapy group, patients with low lncRNA-MBNL1-AS1 expression had significantly lower EFS and OS (60.0%, 8.6%) than patients with high lncRNA-MBNL1-AS1 expression (68.6%, 34.3%) (χ²=7.817, 10.880, all P<0.01). However, in the alloHSCT group, no significant differences were observed in EFS and OS of patients between high and low expression groups of lncRNA-MBNL1-AS1 (all P>0.05). COX multivariate analysis confirmed that age≥60 years old (EFS: HR (95%CI): 6.934 (1.918-25.075),P=0.003;OS: HR (95%CI): 4.119 (1.812-9.364), P=0.001), and low expression of lncRNA MBNL1-AS1 (EFS: HR (95%CI): 0.354 (0.126-0.941), P=0.038; OS: HR (95%CI): 0.424 (0.231-0.778), P=0.006)were independent risk factors for EFS and OS in the chemotherapy group. Conclusion: The long-chain non-coding RNA MBNL1-AS1 is related to the prognosis of AML, and its low expression is an independent poor prognostic factor in AML patients.

Does the presence of an intact primary increase the risk of nonelective colorectal surgery in patients treated with bevacizumab?

AIM

In patients with incurable metastatic colorectal cancer (mCRC), resection of the primary tumour is debated; however, patients with intact primaries may be at a higher risk of complications requiring surgery when receiving treatment with bevacizumab. Our aim was to estimate the risk of nonelective colorectal surgery in patients undergoing bevacizumab therapy for mCRC and evaluate the association between intact primary tumours and risk of nonelective surgery.

METHOD

We designed a population-based, retrospective cohort study using administrative and cancer registry data in Ontario, Canada. We included patients with mCRC who received bevacizumab from 1 January 2008 to 31 December 2014. The primary outcome was nonelective colorectal surgery after initiation of bevacizumab. We determined the cumulative incidence of nonelective colorectal surgery among patients with previously resected and unresected primaries, accounting for the competing risk of death. We explored the relationship between previous resection of the primary and need for nonelective surgery using a cause-specific hazards model, controlling for patient, tumour and treatment factors.

RESULTS

We identified 1840 (32.7%) patients with intact primaries and 3784 (67.3%) patients with prior resection. The cumulative incidence of nonelective surgery 1 year after initiating bevacizumab for all patients was 3.9% (95% CI 3.4-4.5%). One-year cumulative incidence was higher in those with intact primaries than in those with resected primaries (6.1% vs 2.9%, P < 0.0001). After adjustment, an intact primary remained strongly associated with nonelective colorectal surgery (hazard ratio = 2.89, 95% CI 2.32-3.61; P < 0.0001).

CONCLUSION

Bevacizumab is associated with a low but meaningful risk for serious gastrointestinal complications, necessitating vigilance, particularly among patients with an intact primary tumour.

LncRNA PCAT-1 regulated cell proliferation, invasion, migration and apoptosis in colorectal cancer through targeting miR-149-5p

OBJECTIVE

Emerging studies suggested that lncRNA plays an important role in cell progression of multiple cancers. In CRC, the function of some lncRNAs has been verified to be related to cell proliferation, apoptosis, migration and invasion, providing a crucial theoretical basis for the treatment of colorectal cancer. Due to the complexity of the regulation mechanism of cell growth, the regulation mechanism related to lncRNA still needs to be further studied in CRC.

PATIENTS AND METHODS

The qRT-PCR assay was used to carry out the expression of prostate cancer-associated ncRNA transcripts 1 (PCAT-1) and miR-149-5p. The Western blots were used to measure the protein expression of CDK4, Cyclin D1, MMP-2, MMP-9, Bcl-2, Bax and β-actin. Additionally, flow cytometry and MTT assay were used to assess cell apoptosis and cell proliferation, respectively. Moreover, transwell assay was applied to measure the ability of cells migrated and invasion in CRC. Luciferase reporter assay was performed to detect luciferase activities.

RESULTS

In this study, lncRNA PCAT-1 expression was significantly upregulated in CRC cells and tissues. More than that, knockdown of lncRNA PCAT-1 inhibited cell proliferation, migration and invasion while promoted cell apoptosis in CRC cells. Of note, lncRNA PCAT-1 directly targeted miR-149-5p and miR-149-5p expression was significantly downregulated in CRC cells and tissues. Moreover, miR-149-3p reversed the suppressive effects of PCAT-1 on the cell growth of CRC cells.

CONCLUSIONS

Our study demonstrated that LncRNA PCAT-1 regulated cell proliferation, invasion, migration and apoptosis in colorectal cancer through targeting miR-149-5p and provided a new regulatory mechanism of CRC.

Clean 2D superconductivity in a bulk van der Waals superlattice

Advances in low-dimensional superconductivity are often realized through improvements in material quality. Apart from a small group of organic materials, there is a near absence of clean-limit two-dimensional (2D) superconductors, which presents an impediment to the pursuit of numerous long-standing predictions for exotic superconductivity with fragile pairing symmetries. We developed a bulk superlattice consisting of the transition metal dichalcogenide (TMD) superconductor 2H-niobium disulfide (2H-NbS2) and a commensurate block layer that yields enhanced two-dimensionality, high electronic quality, and clean-limit inorganic 2D superconductivity. The structure of this material may naturally be extended to generate a distinct family of 2D superconductors, topological insulators, and excitonic systems based on TMDs with improved material properties.

Establishment and Application of a Dual TaqMan Real-Time PCR Method for Proteus Mirabilis and Proteus Vulgaris

Proteus species are common opportunistic bacteria and foodborne pathogens. The proper detection of Proteus can effectively reduce the occurrence of food-borne public health events. Proteus mirabilis and Proteus vulgaris are the two most important pathogens in the Proteus genus. In this study, a dual TaqMan Real-Time PCR method was established to simultaneously detect and distinguish P. mirabilis and P. vulgaris in samples. The method exhibited good specificity, stability, and sensitivity. Specifically, the minimum detection concentrations of P. mirabilis and P. vulgaris in pure bacterial cultures were 6.08 × 10² colony forming units (CFU)/ml and 4.46 × 10² CFU/ml, respectively. Additionally, the minimum detectable number of P. mirabilis and P. vulgaris in meat and milk was 10³ CFU/g. In addition, the method can be used to distinguish between strains of P. mirabilis and P. vulgaris within two hours. Overall, it is a sensitive, easy-to-use, and practical test for the identification and classification of Proteus in food.

Capsular serotypes, antimicrobial susceptibility, and the presence of transferable oxazolidinone resistance genes in Streptococcus suis isolated from healthy pigs in China

Streptococcus suis is a pig pathogen and a vector of zoonotic diseases that can cause severe systemic infection in humans. S. suis can colonize the nasal cavity, tonsils, and upper respiratory, genital, and digestive tracts in healthy pigs. Here, to determine prevalence, serotype distribution, and antimicrobial susceptibility of S. suis in healthy pigs, we collected 1813 nasal cavity samples from healthy pigs raised on 17 independent farms in six Chinese provinces between 2016 and 2018. We obtained 223 S. suis isolates (12.3 %) and the antimicrobial susceptibility to a panel of 11 antimicrobial agents was measured by microbroth dilution. Most S. suis isolates (98.7 %) were resistant to at least three classes of antimicrobial agents. The optrA gene conferring resistance to oxazolidinones and phenicols was identified in the chromosome of 27 isolates and on a ∼40-kb plasmid in one isolate; to the best of our knowledge, this was the first report of plasmid-borne optrA gene in S. suis. The genetic environment of optrA showed substantial diversity and could be divided into eleven different types. Interestingly, some fragments of the 89 K pathogenicity island (PAI) were observed together with optrA in 3 isolates, which warrants further attention. Capsular serotypes of S. suis isolates were determined by multiplex PCR. Serotype 29 was the most prevalent, followed by serotype 7 and serotype 2. The presence of highly virulent serotype 2 strains may pose a threat to public health.

[Construction and evaluation of a novel diagnosis pathway for 2019-Corona Virus Disease]

Objective: To construct and evaluate a diagnosis pathway (Xiangya pathway) for Corona Virus Disease 2019 (COVID-19). Methods: Consecutive subjects aged ≥12 years old who were screened for COVID-19 were included in Xiangya Hospital of Central South University from January 23 to February 3, 2020, and the subjects were further divided into the inception cohort and the validation cohort. The gender, age, onset time of disease of the subjects were recorded. The information of epidemiological history, fever, and the declined blood lymphocytes were collected as clinical indicators, CT scan was used to evaluate the possibility of COVID-19 and range of lung involvement. According to the current Chinese national standards, throat swabs of suspected cases were collected and the nucleic acid of COVID-19 was detected by reverse transcription-polymerase chain reaction (RT-PCR). The Xiangya pathway was constructed with multi-indexes, compared with clinical indicators, CT results and Chinese national standards, their effectiveness of detecting confirmed cases were verified in the inception and validation cohort. Results: A total of 382 consecutive adults who was screened for COVID-19 were included, and 261 cases were in the inception cohort and 121 cases were in the validation cohort. Among the 382 cases, 192 were males (50.3%) and 190 were females (49.7%), with a median age of 35 years (range: 15-92 years). There were 183 cases (47.9%) with epidemiological history, 275 cases (72.0%) with fever, 212 cases (55.5%) with decreased peripheral blood lymphocytes, 114 cases (29.8%) with positive CT findings, 43 cases (11.3%) with positive CT-COVID-19, and 30 cases (7.9%) with positive virus nucleic acid by throat swab. Compared with clinical indicators, the sensitivity and specificity of CT were 0.950 and 0.704, respectively. The accuracy of CT to make a definite diagnosis was higher than that of epidemiological history, fever, and declined blood lymphocyte count (0.809 vs 0.660, 0.532, 0.596, P=0.001, 0.002, 0.003, respectively). The sensitivity of this pathway and the pathway recommended by the Health Commission of China were both high (all were 1.000), while the specificity and accuracy of the Xiangya pathway were higher than the one recommended by the Health Commission (0.872 vs 0.765, 0.778 vs 0.592, both P<0.001). The CT-COVID-19 reduced the missed diagnosis rate caused by false negative of nucleic acid test (31 vs 64), with difference rate of 51.6%, and the positive rate of nucleic acid test was 64.5% (20/31). In validation cohort, the specificity and accuracy of the Xiangya pathway was 0.967, the positive rate of nucleic acid test was 76.9%(10/13). Conclusions: The Xiangya pathway can predict the nucleic acid test results of COVID-19, and can be applied as a reliable strategy to screen patients with suspected COVID-19 among people aged ≥12 years in areas other than Hubei during the epidemic period of COVID-19. The cohort size needs to be increased for further validation.

Postnatal leptin surge is critical for the transient induction of the developmental beige adipocytes in mice

Beige adipocytes have become a promising therapeutic target to combat obesity. Our senior author Dr. B. Xue previously discovered a transient but significant induction of beige adipocytes in mice during early postnatal development, which peaked at postnatal day (P) 20 and then disappeared thereafter. However, the physiological mechanism underlying the transient induction of the developmental beige cells remains mystery. Interestingly, there exists a postnatal surge of leptin in mice at P10 before the appearance of the developmental beige adipocytes. Given the neurotropic effect of leptin during neuronal development and its role in activating the sympathetic nervous system (SNS), we tested the hypothesis that postnatal leptin surge is required for the transient induction of developmental beige adipocytes through sympathetic innervation. Unlike wild-type (WT) mice that were able to acquire the developmentally induced beige adipocytes at P20, ob/ob mice had much less uncoupling protein 1 (UCP1)-positive multilocular cells in inguinal white adipose tissue at the same age. This was consistent with reduced expression of UCP1 mRNA and protein levels in white fat of ob/ob mice. In contrast, daily injection of ob/ob mice with leptin between P8 and P16, mimicking the postnatal leptin surge, largely rescued the ability of these mice to acquire the developmentally induced beige adipocytes at P20, which was associated with enhanced sympathetic nerve innervation assessed by whole mount adipose tissue immunostaining of tyrosine hydroxylase. Our data demonstrate that the postnatal leptin surge is essential for the developmentally induced beige adipocyte formation in mice, possibly through increasing sympathetic nerve innervation.

[Transbronchial lung cryobiopsy in diffuse lung disease: a pathological analysis of 173 cases]

Objective: To evaluate the value of transbronchial lung cryobiopsy (TBCB) in pathological diagnosis for diffuse lung disease. Methods: The clinicopathological data of 173 patients from the first affiliated hospital of Guangzhou medical university between Jaunary 2017 and June 2019 with transbronchial lung cryobiopsy of diffuse lung disease were retrospectively analyzed and summarized with review. Among 173 cases, TBCB and conventional transbronchial lung biopsy (TBLB) were performed in 54 patients. The size of biopsy samples and diagnostic yield were compared. Results: Among 173 cases, the diagnostic yield was 85.54% (148/173) , 160 (92.49%) cases provided definite diagnosis and valuable pathological results, according to age, sex, occupation, past history, contact history, smoking history, laboratory serology and imaging findings. Among 160 cases, there were 72 cases of known etiology (45.00%), 27 cases of idiopathic interstitial pneumonia (16.88%), 7 cases of granulomatous lesions (4.38%) and 54 cases of other types (33.75%). With TBCB and TBLB in 54 patients, the specimens sizes of TBCB and TBLB were (3.3±1.3) mm(2) and (1.0±0.3) mm(2) respectively (t'=12.67 P<0.01) . The diagnostic yields of TBCB and TBLB were 81.48% (44/54) and 42.59% (23/54) respectively (χ(2)=17.33, P<0.01) . The diagnostic yields of TBCB and TBLB for interstitial lung diseases were 48.15% (26/54) and 5.56% (3/54) respectively (χ(2)=24.94, P<0.01) . However, the diagnostic yields of TBCB and TBLB for the other diffuse lung disease except interstitial lung diseases were 33.33% (18/54) and 37.04% (20/54) respectively, with no significant difference (χ(2)=0.1624, P=0.687). Conclusion: Compared with TBLB, TBCB has obvious advantages and application value in the diagnosis of diffuse pulmonary diseases, especially interstitial pulmonary diseases.

Long non-coding RNA FENDRR inhibits NSCLC cell growth and aggressiveness by sponging miR-761

OBJECTIVE

The aim of this paper is to investigate the functions of long noncoding RNA (lncRNA) FOXF1 Adjacent Non-Coding Developmental Regulatory RNA (FENDRR) in the growth and aggressiveness of non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

The expression of FENDRR in NSCLC tissues and cell lines was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and colony formation assays were conducted to explore the roles of FENDRR on the growth of NSCLC cell. The wound healing and transwell invasion assays were conducted to explore the impact of FENDRR on NSCLC cell migration and invasion. The apoptosis of NSCLC cell was detected using flow cytometer-based Annexin V/Propidium Iodide (PI) dual staining. The xenograft model was conducted to investigate the effect of FENDRR on the growth of NSCLC cell in vivo. The expression of Ki67 was measured by immunohistochemical (IHC) staining using Ki67 antibody. Bioinformatics analysis and Luciferase reporter assay were applied to identify that miR-761 was the target of FENDRR. Additional, colony formation and transwell experiments were utilized to confirm that FENDRR inhibited the growth and aggressiveness of NSCLC cell by regulating miR-761.

RESULTS

We found a marked down-regulation of FENDRR in NSCLC tissues compared to tumor-adjacent tissues. FENDRR down-expression was detected in four NSCLC cell lines (H1650, HCC827, H1975 and A549) compared to the human non-tumorigenic bronchial epithelial cell, BEAS-2B. Low expression of FENDRR was identified as a predictive factor for poor prognosis of patients with NSCLC. The over-regulation of FENDRR inhibited the proliferation, migration and invasion capacities of NSCLC cell and promoted the apoptosis of NSCLC cell in vitro whereas the down-regulation of FENDRR caused the opposite results. Moreover, the over-expression of FENDRR restrained the growth of NSCLC cell in vivo. We found that there were potential binding sites between FENDRR and miR-761 and the level of miR-761 was inversely associated with the expression of ENDRR in NSCLC tissues. Finally, the rescue experiments suggested that the anti-oncogenic role of FENDRR was at least partially mediated by miR-761 in NSCLC.

CONCLUSIONS

We found that FENDRR was down-expressed in NSCLC and the over-expression of FENDRR inhibited the malignant phenotypes of NSCLC cell by binding to miR-761 competitively.

Combined Effect of Osteoporosis and Poor Dynamic Balance on the Incidence of Sarcopenia in Elderly Chinese Community Suburban-Dwelling Individuals

OBJECTIVES

Given the increasing prevalence of osteoporosis and the important role dynamic balanced plays in the assessment of muscle function, we aimed to examine the joint and separate effects of osteoporosis and poor dynamic balance on the incidence of sarcopenia in Chinese elderly individuals.

DESIGN

This study was conducted on 658 (44.4% male) Chinese suburban-dwelling participants with a mean age of 68.42 ± 5.43 years who initially had no sarcopenia and were aged ≥60 years. A quantitative ultrasound scan of each participant's calcaneus with a T score less than -2.5 was used to identify the prevalence of osteoporosis. Sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia criteria. We assessed dynamic balance using the Timed Up and Go Test (TUGT). Participants who scored in the top 20% on the TUGT were defined as having poor dynamic balance.

RESULTS

After a follow-up of three years, the incidence of sarcopenia in the general population was 8.1% (9.6% in males, 6.8% in females). The incidence of sarcopenia was progressively greater in people suffering from both osteoporosis and poor dynamic balance (OR=2.416, 95%CI=1.124-5.195) compared to those who only had osteoporosis (OR=0.797, 95%CI=0.378-1.682) or poor dynamic balance (OR=1.226, 95%CI=0.447-3.363) in models without adjustments. Even after adjusting for potential confounders, the result still held true (OR=2.431, 95%CI=1.053-5.614).

CONCLUSIONS

In our study, we found individuals who suffered from both osteoporosis and poor dynamic balance simultaneously had a significantly higher incidence of sarcopenia than those who suffered from either one or the other.

Decreased expression of ferritin light chain in osteosarcoma and its correlation with epithelial-mesenchymal transition

OBJECTIVE

The purpose of this study was to detect ferritin light chain (FTL) expression level in osteosarcoma (OS), and to clarify whether FTL could offer additional help in diagnosis or therapy.

MATERIALS AND METHODS

First, we assessed FTL level in OS tissues and cells through GEO dataset and tissue microarrays (TMAs). Then, we overexpressed FTL expression in MG-63 cell line. Lastly, we detected the expression of EMT-related signal pathway proteins to study its underlying molecular mechanisms.

RESULTS

GEO dataset and TMAs showed that FTL was down-regulated in OS. After FTL was overexpressed, the proliferation, migration and invasion abilities of OS cells were significantly reduced. Moreover, after FTL overexpressing, the levels of CDH2 and Vimentin were down-regulated with CDH1 up-regulated.

CONCLUSIONS

We revealed that FTL (1) is lower in OS then in normal tissue, (2) is related to metastasis, survival period, and therapeutic response, and (3) may be a tumor-inhibiting factor owing to its inhibition of EMT in OS.

Comparison of the efficacy of two surgical procedures on adenoidal hypertrophy in children

OBJECTIVE

The aim of this study was to explore the treatment effects of two surgical procedures, performed with nasal endoscopy, on treating adenoidal hypertrophy in children.

METHODS

A total of 100 children diagnosed with adenoidal hypertrophy were treated with curettage combined with microwave thermocoagulation and with low-temperature plasma radiofrequency ablation under nasal endoscopic guidance; 6 months after surgery, the effects on snoring, nasal congestion, hearing loss, and gland residue were retrospectively analyzed.

RESULTS

Differences in snoring and hearing loss between the two groups were not statistically significant (P>0.05), but the differences in nasal congestion and gland residue between the two groups were statistically significant (P<0.05); the therapeutic effect was superior in the low-temperature plasma radiofrequency ablation group than in the curettage combined with microwave thermocoagulation group.

CONCLUSION

Low-temperature plasma radiofrequency ablation with nasal endoscopy can achieve a better comprehensive effect on treating adenoidal hypertrophy in children than curettage combined with microwave thermocoagulation.

LncRNA SNHG15 promotes proliferation and migration of lung cancer via targeting microRNA-211-3p

OBJECTIVE

To investigate whether lncRNA (long non-coding RNA) SNHG15 could regulate the proliferation and migration of lung cancer via microRNA-211-3p and its underlying mechanism.

PATIENTS AND METHODS

SNHG15 expression in 55 LC (lung cancer) tissues and 30 normal lung tissues was detected by qRT-PCR (quantitative Real Time-Polymerase Chain Reaction). The relationship between SNHG15 expression and pathological characteristics of LC patients was analyzed the by Kaplan-Meier method. The target microRNA of SNHG15 was predicted by bioinformatics and verified by dual-luciferase reporter gene assay. Viability, cell cycle and migration of LC cells after altering expressions of SNHG15 or microRNA-211-3p were detected by cell counting kit-8 (CCK-8), flow cytometry and transwell assay, respectively.

RESULTS

SNHG15 was highly expressed in LC tissues than that of normal lung tissues. Besides, LC patients with stage I-II presented lower expression of SNHG15 than those with stage III-IV. SNHG15 expression was correlated to tumor size, TNM stage, and lymph node metastasis, whereas not correlated to age and sex of LC patients. For in vitro studies, SNHG15 knockdown resulted in viability reduction, cell cycle arrest and reduced migration of LC cells, which were reversed by the microRNA-211-3p knockdown.

CONCLUSIONS

SNHG15 is highly expressed in LC tissues, which promotes the occurrence and progression of LC via regulating proliferation and migration of LC cells by targeting microRNA-211-3p.

Management of Ganciclovir Resistant Cytomegalovirus Retinitis in a Solid Organ Transplant Recipient: A Review of Current Evidence and Treatment Approaches

Purpose: Cytomegalovirus retinitis (CMVR) is a serious and potentially sight-threatening infection in immunocompromised individuals. Strategies for the management of drug-resistant CMVR are described. Methods: A case of severe bilateral CMVR in a single lung transplant patient, with UL97 mutation conferring ganciclovir-resistance, is presented. Treatment with standard antiviral agent and adjuvant leflunomide, immunosuppression modifications (calcineurin inhibitors and corticosteroid), intravitreal antiviral therapy and novel use of CMV-immunoglobulin is described. A literature review to support drug-resistant CMVR management is presented. Results: Severe and progressive CMV retinitis was refractory to intravitreal foscarnet and systemic leflunomide. Drug-toxicity restricted systemic antiviral therapy options. The use of combined leflunomide and CMV-immunoglobulins, in the absence of viremia, has not been previously reported. Loss of ganciclovir-resistance was eventually observed permitting successful treatment with systemic and intravitreal ganciclovir. Conclusions: Drug-resistant CMVR is a complex clinical challenge. Multiple systemic and local treatment strategies may be necessary but toxicity, resistance, and co-morbidities may severely restrict available options.

P2262Intensity and cost of health care at the end of life among patients with heart failure

Background

Health care utilization increase towards the end of life. There is little known about the intensity of care, including use of in-hospital services, critical care units, and invasive procedures at the end of life in heart failure (HF).

Aims

To determine the type and intensity of health care services offered at the end of life to patients with HF, and to establish the determinants of and costs associated with death in the hospital versus at home.

Methods

We conducted a retrospective cohort study of adults (≥18 years) who died between April 1, 2004 and March 31, 2017 in Ontario, Canada. We included decedents with a diagnosis of HF in the 2 years preceding their death and a hospitalization for HF in their last year of life. We obtained demographic, clinical, healthcare utilization, and healthcare cost data from population-based administrative databases, using unique encrypted identifiers to link records. We calculated direct costs from the perspective of the Ministry of Health in our publicly-funded healthcare system. We used descriptive statistics and a 2-level multivariable logistic regression model) with patients (1st level) nested in regions (2nd level) to assess for predictors of death in the hospital versus at home.

Results

We identified 396,024 adults with HF who died between April 1, 2004 and March 31, 2017. Mean (standard deviation [SD]) age at death was 81.8 (10.7) years, and 48.5% were men. During the last 6 months of life, patients commonly experienced hospitalizations (78.1%), care from >10 different physicians (62.2%); intensive care unit (ICU) admissions (26.4%); mechanical ventilation (18.1%); hemodialysis (6.2%); and cardiac catheterization (3.7%). In the last 6 months of life, patients spent a mean (SD) of 17.4 (23.0) days in the hospital; 2.5 (8.3) days in an ICU; and 1.6 (7.9) days on a ventilator. While the proportion of deaths at home increased from 32.6% in 2004–2005 to 38% in 2016–2017, a majority of patients (53.4%) died in hospital during the study period. Factors independently associated with in-hospital death included age (OR 0.53 [95% CI 0.51–0.55] for age >85 years vs <60 years), sex (OR 0.88 [95% CI 0.87–0.89] for female vs male), and socioeconomic status (OR 0.87 [95% CI 0.85–0.89] for highest vs lowest income quintile). Palliative care services in the last 6 months of life was associated with higher odds of in-hospital death (OR 1.73 [95% CI 1.70–1.76]). Death in hospital was associated with higher mean [SD] healthcare costs in the terminal 6 months of life than death out of hospital ($52,349 [55,649] vs $35,943 [31,907]).

Conclusion

In this large cohort study in Ontario, Canada, patients with HF commonly received in-hospital, intensive, and invasive care in the last 6 months of life, and a majority of patients died in hospital. Death in hospital was associated with higher costs of care in the terminal 6 months than death outside hospital.

Acknowledgement/Funding

Heart and Stroke Foundation of Ontario, Canadian Institutes of Health Research