[Inference of start time of resurgent COVID-19 epidemic in Beijing with SEIR dynamics model and evaluation of control measure effect]

Objective: To infer the start time of the resurgent COVID-19 epidemic in Xinfadi wholesale market in Beijing in June 2020 and evaluate the effect of comprehensive prevention and control measures in this epidemic. Methods: SEIR dynamics model was used to fit daily onset infections to search the start date of this resurgent COVID-19 epidemic in Beijing. The number of cumulative infections from June 12 to July 1 in Beijing were fitted considering different levels of control strength. Results: The current reemerged COVID-19 epidemic in Beijing probably started between May 22 and May 28 (cumulative probability: 95%), with the highest probability on May 25 (23%). The R(0) of the current reemerged COVID-19 epidemic was 4.22 (95%CI: 2.88-7.02). Dynamic model fitting suggested that by June 11, the cumulative number of COVID-19 cases would reached 99 (95%CI: 77-121), which was in line with the actual situation, and without control, by July 1, the cumulative number of COVID-19 cases would reach 65 090 (95%CI: 39 068-105 037). Since June 12, comprehensive prevention and control measures have been implemented in Beijing, as of July 1, compared with uncontrolled situation, the number of infections had been reduced by 99%, similar to the fitting result of a 95% reduction of the transmission rate. The sensitivity analysis showed consistent results. Conclusions: For the emergent outbreak of COVID-19, the dynamics model can be used to infer the start time of the transmission and help tracing the source of epidemic. The comprehensive prevention and control measures taken in Beijing have quickly blocked over 95% of the transmission routes and reduced 99% of the infections, containing the sudden epidemic timely and effectively, which have value in guiding the prevention and control of the epidemic in the future.

[Using Markov Chain Monte Carlo methods to estimate the age-specific case fatality rate of COVID-19]

Objectives: The COVID-19 epidemic has swept all over the world. Estimates of its case fatality rate were influenced by the existing confirmed cases and the time distribution of onset to death, and the conclusions were still unclear. This study was aimed to estimate the age-specific case fatality rate of COVID-19. Methods: Data on COVID-19 epidemic were collected from the National Health Commission and China CDC. The Gamma distribution was used to fit the time from onset to death. The Markov Chain Monte Carlo simulation was used to estimate age-specific case fatality rate. Results: The median time from onset to death of COVID-19 was M=13.77 (P(25)-P(75): 9.03-21.02) d. The overall case fatality rate of COVID-19 was 4.1% (95%CI: 3.7%-4.4%) and the age-specific case fatality rate were 0.1%, 0.4%, 0.4%, 0.4%,0.8%, 2.3%, 6.4%, 14.0 and 25.8% for 0-, 10-, 20-, 30-, 40-, 50-, 60-, 70- and ≥80 years group, respectively. Conclusions: The Markov Chain Monte Carlo simulation method adjusting censored is suitable for case fatality rate estimation during the epidemic of a new infectious disease. Early identification of the COVID-19 case fatality rate is helpful to the prevention and control of the epidemic.

Sirt6 regulates autophagy in AGE-treated endothelial cells via KLF4

Aims

To explore Sirt6 regulating autophagy in endothelial cells and the specific mechanism of this function with involvement of KLF4.

Materials and methods

Human umbilical vein endothelial cells were cultured with advanced glycation end products (AGE) treatment. Adv-Sirt6, LV-Sirt6 and LV-KLF4 were used to knockup Sirt6 and knockdown Sirt6 and KLF4 respectively. qPCR and Western Blotting were used to detect the mRNA and protein expression of Sirt6 and KLF4. Laser scanning confocal microscope was used to observe the LC3-II marked autophagosomes. Wildlife BALB/c mice were treated with STZ to produce diabetic mice model. AAV-Sirt6 was injected by tail vein injection to achieve Sirt6 knockdown. HE staining and scanning electron microscope were used to observe the aortic intima condition and autophagosomes number respectively.

Results

In AGE treated HUVECs, knockdown of Sirt6 led to impaired autophagy level along with less expression of autophagic markers LC3-II, Beclin-1, Lamp2 and autophagic marker p62. Knockdown and knockup of Sirt6 directly affected KLF4 expression level but KLF4 didn't have any effect on Sirt6 expression. Knockout of KLF4 offset the augmented autophagy caused by overexpression of Sirt6. In high-fat fed diabetic mice, downregulation of Sirt6 led to better cardiac function along with less autophagosomes and impaired aortic intima integrity.

Conclusions

Sirt6 improves autophagy both in vivo and in vitro and Sirt6 regulates autophagy via KLF4 in HUVECs.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China

Comparing nanoparticle polymeric micellar paclitaxel and solvent-based paclitaxel as first-line treatment of advanced non-small-cell lung cancer: an open-label, randomized, multicenter, phase III trial

BACKGROUND

Polymeric micellar paclitaxel (pm-Pac) is a novel Cremophor EL-free, nanoparticle micellar formulation of paclitaxel. We aimed to compare the efficacy and safety between pm-Pac plus cisplatin and solvent-based paclitaxel (sb-Pac) plus cisplatin in advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

A total of 448 stage IIIB to IV NSCLC patients were randomly assigned (2:1) to receive six 3-week cycles of either pm-Pac (230 mg/m²) plus cisplatin (70 mg/m²; n = 300), followed by dose escalation of pm-Pac to 300 mg/m² from the second 3-week cycle if prespecified toxic effects were not observed after the first cycle, or sb-Pac (175 mg/m²) plus cisplatin (70 mg/m²; n = 148). The primary end point was objective response rate (ORR) assessed by independent review committees (IRCs). The secondary end points included IRC-assessed progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Patients in the pm-Pac-plus-cisplatin group showed significant improvements in IRC-assessed ORR compared with those in the sb-Pac-plus-cisplatin group (50% versus 26%; rate ratio 1.91; P < 0.0001). Additionally, subgroup analysis showed that a higher ORR was consistently observed in both squamous and nonsquamous histological types. IRC-assessed median PFS was significantly higher in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group (6.4-month versus 5.3-month; hazard ratio 0.63; P = 0.0001). Median OS was not significantly different between the two groups. The incidence of treatment-related serious adverse events (9% versus 18%; P = 0.0090) was significantly lower in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group.

CONCLUSION

Pm-Pac plus cisplatin yielded superior ORR and PFS along with a favorable safety profile and should become an option for patients with advanced NSCLC.

CLINICAL TRIAL IDENTIFIER

ClinicalTrials.gov NCT02667743; https://clinicaltrials.gov/ct2/show/NCT02667743.

Apply Molecular Method To Diagnosis A Very Rare Bone Primary Myoepithelial Tumor: A Case Report

Introduction/Objective

A 38-year-old female without a history of trauma and malignancy presented with left knee pain and swelling for two weeks. MRI and PET scan find a left knee mass arising from the bone along the medial metaphysis of the distal femur. She underwent femur resection, and the specimen was sent for pathology evaluation.

Methods

Grossly, the cut surface of the sample revealed a 4.5 x 2 cm area of hemorrhagic softening of the bone with adjacent soft tissue nodules. Microscopically, the tumor showed biphasic or multiphase morphologic features, prominently presented with areas showing well-differentiated epithelial features and other areas with spindling and sheets of tumor cells. Areas suspicious for a vascular invasion were seen at the periphery of the soft tissue extension of the tumor. Immunohistochemistry stains showed the tumor cells are positive for vimentin, AE1/3, EMA, CK7, CK19, GATA3, and BRST2; and are negative for S100, HMB45, GFAP, Calponin, CDX2, PAX8, WT1, P63, CD34, and ER. The molecular test showed positive for the ESWR1 gene but negative for SYT gene translocation.

Results

A diagnosis of primary myoepithelial carcinoma of bone extension into surrounding soft tissue was made.

Conclusion

The most challenging differential diagnosis for this case is metastatic breast cancer. Many of the positive epithelial stains distinctly highlight the epithelial featured geographic areas sparing the background spindled stroma. The positive staining of GATA3 and BRST2, two commonly used breast linage markers, is unusual and not known in myoepithelial carcinoma. In light of the EWSR1 positive and SYT FISH negative results, combined with the morphologic features, locations as well as negative PET scan against its breast origins. Although many myoepithelial markers, such as S100, Calponin, P63, and GFAP were negative, make this case very unique. The molecular diagnosis is the mainstay for this final diagnosis.

Pulmonary Cement Emboli After Kyphoplasty: A Case Of Bilateral Pulmonary Emboli And Exacerbation Of Interstitial Lung Disease

Introduction/Objective

Osteoporosis often complicates the management of vertebral conditions, including spinal stenosis and vertebral fractures in the geriatric population. In addition to pharmacologic pain management; surgical interventions are employed if the pain is not adequately managed. The surgical interventions include vertebroplasty and kyphoplasty. These procedures involve the introduction of a cement polymer, Polymethylmethacrylate (PMMA), into the vertebral body. Cement leakage is a reported complication more commonly seen in vertebroplasty (30-75%) compared to kyphoplasty (8-33%). This occurs due to distant leakage of cement into the venous plexus or retrograde migration into the aorta which leads to pulmonary cement emboli (PCE). PCE are usually asymptomatic; few patients are symptomatic; seen in 0.9% for vertebroplasty and 0.4% for kyphoplasty. PMMA has a prothrombotic effect, contributing to the thrombosis of the pulmonary vessels. Symptoms typically arise weeks to months after the procedure. In addition, it has been reported that rarely PCE can present with ARDS especially in patients with interstitial lung abnormalities.

Methods

We present a case of an 80-year-old female with a history of hypertension, diabetes mellitus and osteoporosis who underwent a kyphoplasty procedure with use of PMMA for spinal stenosis. Her post-operative course was complicated by multiple surgical revisions. She was noted to have pulmonary cement emboli five months post kyphoplasty and developed significant shortness of breath eight months post procedure. She ultimately developed cardio-pulmonary failure and was found to have bilateral pulmonary emboli and cement emboli at autopsy. Microscopic examination of the cement emboli documented round to oval vacuole-like cavities within and around blood vessels consistent with PMMA.

Conclusion

The histo-pathologic findings of cement emboli are not well documented in human beings compared to animal models. We attempt to highlight the gross and microscopic findings of PMMA cement emboli which is essential in the clinical-histo-pathologic correlation and characterization of pulmonary emboli at autopsy.

Identification Of Liver Fluke Eggs In Bile Duct Brush Cytology In An 82 Year Old Man With A Hepatic Mass: Report Of A Case

Introduction/Objective

Clonorchis sinensis infects the liver, gallbladder, and bile ducts in humans. It is acquired via consumption of raw/undercooked fish, crabs, or crayfish in endemic areas. Though majority are asymptomatic, long lasting infections may cause severe disease. Without treatment, human infections may persist for the parasite lifespan (25–30 years). Diagnosis in cytology is challenging with a potentially acellular sample with miniscule eggs that can be overlooked as an artifact. Here we reported a rare case of liver fluke eggs diagnosed in bile duct brush cytology.

Methods

An 82 year old man who emigrated from China 20 years prior presented to the hospital with worsening jaundice for 2 weeks. Abdominal CT revealed a 4.8 x 2.9 cm central right hepatic lobe mass extending to the hilum, obstructing the bile ducts, resulting in severe intrahepatic ductal dilatation and stricture and focal occlusion of the right anterior portal vein. His CBC revealed eosinophilia. Bile duct brushing was submitted for cytology.

Results

ThinPrep and cell block showed oval-shaped parasite eggs measuring 10-24 µm. There was no other cellular matter. Eggs had a convex operculum resting on “shoulders” at the smaller end of the egg. At the opposite (abopercular) end, a small knob or hook-like protrusion was often visible. Wet mounts revealed visible miracidium inside the eggs. These findings were compatible with liver fluke eggs.

Conclusion

Cytologic microbiologic features of fluke eggs confirmed the findings. The most important features are the shape and size of the eggs; The seated operculum with its prominent “shoulders”, a small knob at the abopercular end, which can distinguish them from acellular artifact or a human cell. The cytologic and microbiologic features combined with the travel history and clinical presentation can aid in achieving the diagnosis.

Nanoscale bubble delivered YCD-TK/Cx26 gene therapeutic system suppresses tumor growth by inducing necrosis of tumor tissues in mouse Xenograft bladder cancer models

OBJECTIVE

Bladder cancer is considered as the fifth most common cancer in the whole world. This study aimed to investigate the anti-tumor effects of Nanoscale bubbles delivered yeast cytosine deaminase thymidine kinase/connexin 26 (YCD-TK/Cx26) on tumor cell proliferation and tumor growth.

MATERIALS AND METHODS

Nanoscale bubble was prepared using thin-film hydration-sonication method. Nanoscale bubble-LV5-YCD-TK+PCD-Cx26 was generated and transfected into BIU-87 cells. MTT assay was employed to detect cell viability. Apoptosis was determined using a flow cytometry assay. YCD-TK and Cx26 expressions were detected using Western blot and Real Time-PCR (RT-PCR). BIU-87 cells were transplanted into mice to establish Xenograft models. The tumor volume was recorded. HE staining was used to examine necrosis areas in tumor tissues.

RESULTS

Nanoscale bubble (Nanoscale bubble-LV5-YCD-TK+PCD-Cx26) successfully mediated YCD-TK and Cx26 gene expression in BIU-87 cells. Nanoscale bubble delivered YCD-TK/Cx26 expression significantly inhibited cell viability and induced apoptosis compared to Nanoscale bubble-LV5-YCD-TK and Nanoscale bubble group (p<0.05). Nanoscale bubble delivered YCD-TK/Cx26 expression triggered significantly higher levels of bystander effect compared to single YCD-TK or single Cx26 gene (p<0.05). Nanoscale bubble delivered YCD-TK/Cx26 expression significantly reduced tumor volume in mouse Xenograft bladder cancer model compared to LV5-YCD-TK and 5-FC+GCV group (p<0.05). Nanoscale bubble delivered YCD-TK/Cx26 expression significantly reduced the necrosis of tumor tissues in mouse Xenograft bladder cancer model compared to LV5-YCD-TK group and 5-FC+GCV group (p<0.05).

CONCLUSIONS

Nanoscale bubble delivered YCD-TK/Cx26 gene therapeutic system efficiently reduced BIU-87 cell proliferation in vitro, and suppressed tumor growth by inducing necrosis of tumor tissues in mouse Xenograft bladder cancer models.

Influence of mesenchymal stem cells on respiratory distress syndrome in newborn swines via the JAK-STAT signaling pathway

OBJECTIVE

Acute respiratory distress syndrome (ARDS) threatens humans' health worldwide, causing huge labor and economic cost investment. This study aims to explore whether mesenchymal stem cells (MSCs) affect RDS in newborn swines via the Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling pathway by the establishment of the model of the disease.

MATERIALS AND METHODS

The phosphorylation of the JAK-STAT signal transduction proteins was first detected via Western blotting to verify the regulatory effect of MSCs on RDS in newborn swines through the JAK-STAT signaling pathway. Then, the Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was utilized to analyze the influences of the injection of MSCs into the blood of newborn model RDS swines on inflammatory factors in vivo. To further demonstrate the signal transduction function put forwarded, the RT-PCR and enzyme-linked immunosorbent assay (ELISA) were adopted to analyze the influences of the JAK-STAT signaling pathway inhibitor on the expression of the signature proteins of RDS in newborn swines and the changes in the inflammatory factors.

RESULTS

MSCs induced the phosphorylation of JAK and STAT, and they activated the JAK-STAT signal transduction of RDS in newborn swines. Compared with those in normal saline group, the interleukin (IL)-2, IL-6, IL-8, and tumor necrosis factor-α (TNF-α) expression levels in MSC group were increased, namely, MSCs substantially promoted their expression levels (p<0.05), but those of IL-10 and IL-13 were significantly decreased (p<0.05).

CONCLUSIONS

The inhibitor of the JAK-STAT signaling pathway can suppress the therapeutic effect of MSCs on RDS in newborn swines.

Silence of MiR-9 protects depression mice through Notch signaling pathway

OBJECTIVE

To investigate the potential influence of micro ribonucleic acid (miR)-9 on depressive behaviors of depression mice.

MATERIALS AND METHODS

Depression model in mice was established via chronic unpredictable mild stress. A total of 36 C57BL/6 mice were randomly divided into control group (control mice, n=12), model group (depression mice administrated with control lentivirus, n=12) and miR-9 low-expression group (depression mice administrated with LV-miR-9-shRNA lentivirus, n=12). After 6 weeks, the depressive behaviors of mice were evaluated by behavioral experiments. Mice were then sacrificed for harvesting the hippocampus. Relative level of miR-9 in mouse hippocampus was determined via quantitative polymerase chain reaction (qPCR). Moreover, the number of newborn neurons in the hippocampus in each group was detected via immunofluorescence assay. Expression levels of doublecortin (DCX), post-synaptic density protein 95 (PSD95) and Notch signaling pathway in the hippocampus in each group were detected via Western blotting.

RESULTS

In the open field test, there were no significant differences in the crossing score and rearing score among control group, model group and miR-9 low-expression group (p>0.05). The immobility time of mice in tail suspension test and forced swimming test increased significantly in model group compared with that in control group (p<0.01), while it was significantly shorter in miR-9 low-expression group than that in model group (p<0.01). The expression of miR-9 in mouse hippocampus in model group was significantly higher than that in control group and miR-9 low-expression group (p<0.01). In miR-9 low-expression group, the number of newborn neurons in the hippocampus was significantly larger than that in control group and model group (p<0.01). Protein levels of both DCX and PSD95 were significantly higher in control group than those in model group (p<0.01). Besides, protein levels of Notch intracellular domain (NICD), Hes1 and Jag1 in the hippocampus in model group were remarkably declined compared with those in control group (p<0.01), which were higher in miR-9 low-expression group.

CONCLUSIONS

MiR-9 is upregulated in the hippocampus of depression mice. Silence of miR-9 in the hippocampus can effectively activate the Notch signaling pathway, promote the neuronal regeneration in the hippocampus and improve the depressive symptoms of mice.

[CAR T-cell bridging to allo-HSCT for relapsed/refractory B-cell acute lymphoblastic leukemia: the follow-up outcomes]

Objective: This study aims to investigate the efficacy and safety of chimeric antigen receptor (CAR) T-cell bridging allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of recurrent and refractory acute B-lymphocytic leukemia (R/R B-ALL) . Methods: A total of 50 R/R B-ALL patients who underwent CAR T-scell therapy to bridge allo-HSCT in the First Affiliated Hospital of Soochow University from January 2017 to May 2019 were retrospectively analyzed. The overall survival (OS) rate, event-free survival (EFS) rate, cumulative recurrence rate (CIR) , and transplant-related mortality (TRM) of patients with different bone marrow minimal residual disease (MRD) levels were analyzed before and after CAR T-cell infusion and before allo-HSCT. Results: The response rate of CAR T-cell therapy and the incidence rate of severe cytokine release syndrome were 92% and 28% , respectively. During 55 infusions, no treatment-related deaths occurred in any of the patients. The median time of CAR T-cell infusion to allo-HSCT was 54 (26-232) days, the median follow-up time after CAR T-cell infusion was 637 (117-1097) days, and the 1-year OS and EFS rates were (80.0±5.7) % and (60.0±6.9) % . The 1-year CIR and TRM after allo-HSCT were (28.0±0.4) % and (8.0±0.2) % . After CAR T-cell infusion and before allo-HSCT, patients with bone marrow MRD<0.01% had a significantly longer EFS [ (70.0±7.2) % vs (20.0±12.6) % , P<0.001; (66.7±7.5) % vs (36.4±14.5) % , P=0.008]and lower CIR [ (25.0±0.5) % vs (70.0±2.6) % , P<0.001; (23.08±0.47) % vs (45.45±2.60) % , P=0.038]. Conclusion: CAR T-cell therapy bridging allo-HSCT is safe and effective for recurrent and refractory B-ALL.

Effectiveness of health promoting school program: The relationship of HPS award level and outcome

Background

According to Taiwan health promoting school (HPS) accreditations program, the school was recognized with a gold award, silver award, bronze award, participation award, and non-awards. Previous studies have foci on the effectiveness of the HPS from the perspective of students' health behaviors. The main purpose of this study is to compare the students' health and social outcomes in different HPS award levels to assess the effectiveness of the HPS program.

Methods

This cross-sectional survey was conducted to 121 schools registering HPS accreditation program in 2018. Overall, a total of 8812 elementary, junior and senior high school students completed the questionnaire. The accredited schools were classified into four categories according to the award level: excellent (5 schools with gold), good (32 schools with silver), fair (23 schools with bronze and 18 schools with participation), and poor (44 schools with non-award). The outcome variables included perceived health status, well-being, and quality of life. The descriptive statistics and ANOVA were analysed using SPSS 20.0 software.

Results

There were awards level differences of students' health (F = 10.66, p&lt;.001) and social outcomes (e.g. well-being: F = 3.76, p&lt;.01; quality of life: F = 11.58, p&lt;.001). From the perspective of health outcomes, the results found that schools with excellent level (Mean=3.59), good level (Mean=3.52), and fair level (Mean=3.47) were better in students' perceived health status than schools with poor level (Mean=3.38). Similarly, the results showed that schools with excellent level were better in students' well-being (Mean=7.63) and quality of life (Mean=34.56) than schools with poor level (Mean=7.25; 33.56).

Conclusions

Students from schools with excellent levels exhibited better health and social outcomes. The finding suggests that future studies evaluate and track the effectiveness to conduct the longitudinal study, and the HPS program should be effectively implemented and sustained.

Key messages

To explore the effectiveness of the health promoting school program in health and social outcomes. Note: This work was funded by the Health Promotion Administration, Ministry of Health and Welfare. Health promoting schools award level is related to students’ perceived health status, well-being, and quality of life.

[Principles of dynamics model and its application in forecasting the epidemics and evaluation the efforts of prevention and control interventions]

During the epidemics of COVID-19 in domestic China and recently continuing rapid spread worldwide, a bunch of studies fitted the epidemics by transmission dynamics model to nowcast and forecast the trend of epidemics of COVID-19. However, due to little known of the new virus in early stage and much uncertainty in the comprehensive strategies of prevention and control for epidemics, majority of models, not surprisingly, predict in less accuracy, although the dynamics model has its great value in better understanding of transmission. This comment discusses the principle assumptions and limitations of the dynamics model in forecasting the epidemic trend, as well as its great potential role in evaluating the efforts of prevention and control strategies.

Characterization of a blaIMP-4-carrying plasmid from Enterobacter cloacae of swine origin

OBJECTIVES

To characterize an MDR blaIMP-4-harbouring plasmid from Enterobacter cloacae EC62 of swine origin in China.

METHODS

Plasmid pIMP-4-EC62 from E. cloacae EC62 was transferred by conjugation via filter mating into Escherichia coli J53. Plasmid DNA was extracted from an E. coli J53 transconjugant and sequenced using single-molecule real-time (SMRT) technology. MIC values for both the isolate EC62 and the transconjugant were determined using the broth microdilution and agar dilution methods. Plasmid stability in both the isolate EC62 and the transconjugant was assessed through a series of passages on antibiotic-free media.

RESULTS

Plasmid pIMP-4-EC62 is 314351 bp in length, encodes 369 predicted proteins and harbours a novel class 1 integron carrying blaIMP-4 and a group II intron. The blaIMP-4-bearing plasmid belongs to the IncHI2/ST1 incompatibility group. Sequence analysis showed that pIMP-4-EC62 carries four MDR regions and several gene clusters encoding heavy metal resistance. Plasmid pIMP-4-EC62 was stably maintained in both the E. cloacae EC62 isolate and the transconjugant E. coli J53-pIMP-4-EC62 in the absence of selective pressure. Analysis of the evolutionary relatedness of selected IncHI2 plasmids indicates that ST1-type plasmids are key carriers of carbapenemase genes among IncHI2 plasmids.

CONCLUSIONS

pIMP-4-EC62 represents the first fully sequenced IncHI2-type blaIMP-4-harbouring plasmid from E. cloacae in China. Co-location of blaIMP-4 with other resistance genes on an MDR plasmid is likely to further accelerate the dissemination of blaIMP-4 by co-selection among bacteria from humans, animals and the environment under the selective pressure of other antimicrobial agents, heavy metals and disinfectants.

Melatonin activates autophagy via the NF-κB signaling pathway to prevent extracellular matrix degeneration in intervertebral disc

OBJECTIVE

This study investigated whether melatonin alleviates intervertebral disc degeneration (IVDD) by promoting autophagy through inhibiting the NF-κB signaling pathway.

METHODS

Magnetic resonance imaging (MRI), hematoxylin and eosin (H&E) staining and Safranin-O staining were used to measure disc degeneration in rat needle puncture IVDD models, and melatonin was injected intraperitoneally in the treated group to test its function. The expression of autophagy and extracellular matrix (ECM) degeneration related-markers were measured in the discs using immunohistochemistry. Transmission electron microscopy was used to evaluate the activation of autophagy in human nucleus pulposus (NP) tissues with different degenerated statuses. The expression of autophagy and disc degeneration related-markers were detected in NP cells by Western blot, RT-qPCR, and immunofluorescence analyses. NF-κB signaling pathway involvement was studied by lentivirus-mediated knockdown, Western blotting, and immunohistochemistry and immunofluorescence staining.

RESULTS

Melatonin prevented IVDD development in vivo and in vitro. Compared to non-degenerated disc tissues, degenerated human NP tissues showed a decrease in the autophagy-specific marker LC3B and the numbers of autophagosomes and autolysosomes, whereas the p62 level was increased; similar results were observed in rat IVDD models, indicating a negative correlation between autophagy and IVDD. Furthermore, both in vivo and in vitro studies found that melatonin application induced autophagy and reduced ECM disc degradation. Melatonin was also shown to regulate autophagy by inhibiting the NF-κB signaling pathway in vivo and vitro.

CONCLUSION

This study indicates that melatonin prevents IVDD by promoting autophagy, indicating its possible therapeutic potential for controlling the progression of IVDD.

Genetic characterization of an MDR/virulence genomic element carrying two T6SS gene clusters in a clinical Klebsiella pneumoniae isolate of swine origin

OBJECTIVES

Multiresistant Klebsiella pneumoniae isolates rarely cause infections in pigs. The aim of this study was to investigate a multiresistant porcine K. pneumoniae isolate for plasmidic and chromosomal antimicrobial resistance and virulence genes and their genetic environment.

METHODS

K. pneumoniae strain ZYST1 originated from a pig with pneumonia. Antimicrobial susceptibility testing was performed using broth microdilution. Conjugation experiments were conducted using Escherichia coli J53 as the recipient. The complete sequences of the chromosomal DNA and the plasmids were generated by WGS and analysed for the presence of resistance and virulence genes.

RESULTS

The MDR K. pneumoniae ST1 strain ZYST1 contained three plasmids belonging to incompatibility groups IncFIIk5-FIB, IncI1 and IncX4, respectively. The IncFIIk5-FIB plasmid carried the resistance genes aadA2, mph(A), sul1 and aph(3')-Ia, and the IncI1 plasmid carried aadA22 and erm(B). No resistance genes were present on the IncX4 plasmid. Plasmids related to the aforementioned three plasmids were also present in other Enterobacteriaceae species from humans, animals and the environment. Bioinformatic analyses identified a chromosomal 904 kb MDR element flanked by two copies of ISKpn26. This element included virulence factors, such as a type VI secretion system (T6SS) and genes for type 1 fimbriae, the toxin-antitoxin system HipA/HipB, antimicrobial resistance genes, such as blaSHV-187, mdtk, catA and the multiple antibiotic resistance operon marRABC, and heavy metal resistance determinants, such as chrB/chrA and tehA/tehB.

CONCLUSIONS

This study reports a novel 904 kb MDR/virulence genomic element and three important plasmids coexisting in a clinical K. pneumoniae isolate of animal origin.

ADMA mediates gastric cancer cell migration and invasion via Wnt/β-catenin signaling pathway

Objective

To explore the role of ADMA in gastric cancer.

Methods

The specimens of 115 gastric cancer patients were analyzed by ELISA and survival analysis. Functional assays were used to assess the effects of ADMA on gastric cancer cells. Experiments were conducted to detect the signaling pathway induced by ADMA in GC.

Results

Gastric cancer patients with high ADMA levels had poor prognosis and low survival rate. Furthermore, high level of ADMA did not affect the proliferation while promoted the migration and invasion of gastric cancer cell. Moreover, ADMA enhanced the epithelial–mesenchymal transition (EMT). Importantly, ADMA positively regulated β-catenin expression in GC and promoted GC migration and invasion via Wnt/β-catenin pathway.

Conclusions

ADMA regulates gastric cancer cell migration and invasion via Wnt/β-catenin signaling pathway and which may be applied to clinical practice as a diagnostic and prognostic biomarker.

Electronic supplementary material

The online version of this article (10.1007/s12094-020-02422-7) contains supplementary material, which is available to authorized users.

Characterization of carbapenem-resistant Klebsiella pneumoniae in a tertiary hospital in Fuzhou, China

Aims

The emergence of carbapenem‐resistant Klebsiella pneumoniae (CRKP) strains has led to increased mortality and morbidity rates. Tigecycline, a new class of broad‐spectrum glycyl‐tetracycline antibiotics, has been used to target multi‐ and pan‐drug‐resistant bacterial infections. This study aimed to assess the molecular characteristics of CRKP in a tertiary hospital, and its susceptibility to tigecycline, to create a reference for hospital infection control and clinical drug use.

Methods and Results

We retrieved patient clinical information and CRKP characterization from medical records and detected the MIC of tigecycline using the micro‐broth dilution method. Multi‐locus sequence typing was performed, and antibiotic resistance genes associated with CRKP were detected by qPCR. A total of 166 CRKP strains were detected in the sputum, urine and blood among intensive care unit patients (average age, 69·6 years). The most infrequently observed resistance genes were amikacin resistance genes, followed by tobramycin resistance genes. KPC‐2, CTX‐M9 and CTX‐M1 were the most frequently detected resistance genes.

Conclusions

No strain was resistant to tigecycline (MIC ≥ 8 µg ml⁻¹). Twenty‐four sequence types were identified, with ST11 being the most common type.

Significance and Impact of the Study

Clinicians and infection control experts should be aware of CRKP prevalence to facilitate clinical treatment and improve nosocomial infection control.

[Fitting and forecasting the trend of COVID-19 by SEIR(+CAQ) dynamic model]

Objectives: Fitting and forecasting the trend of COVID-19 epidemics. Methods: Based on SEIR dynamic model, considering the COVID-19 transmission mechanism, infection spectrum and prevention and control procedures, we developed SEIR(+CAQ) dynamic model to fit the frequencies of laboratory confirmed cases obtained from the government official websites. The data from January 20, 2020 to February 7, 2020 were used to fit the model, while the left data between February 8-12 were used to evaluate the quality of forecasting. Results: According to the cumulative number of confirmed cases between January 29 to February 7, the fitting bias of SEIR(+CAQ) model for overall China (except for cases of Hubei province), Hubei province (except for cases of Wuhan city) and Wuhan city was less than 5%. For the data of subsequent 5 days between February 8 to 12, which were not included in the model fitting, the prediction biases were less than 10%. Regardless of the cases diagnosed by clinical examines, the numbers of daily emerging cases of China (Hubei province not included), Hubei Province (Wuhan city not included) and Wuhan city reached the peak in the early February. Under the current strength of prevention and control, the total number of laboratory-confirmed cases in overall China will reach 80 417 till February 29, 2020, respectively. Conclusions: The proposed SEIR(+CAQ) dynamic model fits and forecasts the trend of novel coronavirus pneumonia well and provides evidence for decision making.

Abstracts of published randomised controlled trials in Endodontics: Reporting quality and spin

AIMS

To assess the reporting quality of recently published randomised controlled trial (RCT) abstracts in Endodontics, to investigate factors associated with reporting quality, and to evaluate the existence and characteristics of spin. Spin refers to reporting strategies that distort study results and misguide readers.

METHODOLOGY

The PubMed database was searched to identify abstracts of RCTs in the field of Endodontics published during 2017 to 2018. Two authors assessed the reporting quality of each included abstract using the original 16-item CONSORT for Abstracts checklist, with the overall quality score (OQS, range: 0 to 16) being the primary outcome measure. For each individual item, a score of '1' was given if it was described adequately, and '0' if the description was inadequate. Linear regression analyses were conducted to identify factors associated with reporting quality. For the evaluation of spin, two authors selected parallel-group RCTs with a nonsignificant primary outcome from the included abstracts, and evaluated independently the existence and characteristics of spin among these abstracts.

RESULTS

A total of 162 abstracts were included for assessment of reporting, for which the mean OQS was 3.97 (SD, 1.30; 95 % CI, 3.77 to 4.17). According to multivariable analysis, origin from Europe (P=0.001) and reporting of the exact P value (P=0.020) were significantly associated with better reporting. Forty abstracts with statistically nonsignificant results for their primary outcome were included for spin evaluation, among which 34 (85.0%) had at least one type of spin. Thirty-two abstracts (94.1%) had spin in their conclusions section, and six abstracts (17.6%) had spin in the results section.

CONCLUSIONS

The reporting quality of RCT abstracts in Endodontics needs to be improved. The occurrence rate of spin in the sample of abstracts of RCTs in the field of Endodontics was high. Relevant stakeholders are recommended to be familiar with the CONSORT for Abstracts guideline and develop active strategies to ensure its implementation.