Publications by authors named "Tengfei Zhang"

137 Publications

Fretting Wear Behavior of Three Kinds of Rubbers under Sphere-On-Flat Contact.

Materials (Basel) 2021 Apr 23;14(9). Epub 2021 Apr 23.

School of Mechanical Engineering, Tianjin University, Tianjin 300350, China.

Rubbers are widely used in various fields as the important sealing materials, such as window seal, door seal, valve, pump seal, etc. The fretting wear behavior of rubbers has an important effect on their sealing performance. This paper presents an experimental study on the fretting wear behavior of rubbers against the steel ball under air conditions (room temperature at 20 ± 2 °C and humidity at 40%). Three kinds of rubbers, including EPDM (ethylene propylene diene monomer), FPM (fluororubber), and NBR (nitrile-butadiene rubber), are considered in experiments. The sphere-on-flat contact pattern is used as the contact model. The influences of the displacement amplitude, normal force, frequency, and rubber hardness on the fretting wear behavior are discussed in detail. White light profiler and scanning electron microscope (SEM) are used to analyze the wear mechanism of the rubber surface. The fretting wear performances of three rubbers are compared by considering the effect of the displacement amplitude, normal force, frequency, and rubber hardness. The results show that NBR has the most stable friction coefficient and the best wear resistance among the three rubbers.
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http://dx.doi.org/10.3390/ma14092153DOI Listing
April 2021

Effects of S1PR2 antagonist on blood pressure and angiogenesis imbalance in preeclampsia rats.

Mol Med Rep 2021 Jun 21;23(6). Epub 2021 Apr 21.

Obstetrics Department, Jinhua Maternal and Child Health Hospital, Jinhua, Zhejiang 321000, P.R. China.

Preeclampsia (PE), a hypertensive multisystem disorder, can lead to increased maternal and fetal mortality and morbidity. Sphingosine‑1‑phosphate (S1P) plays various roles, depending on the cell type, by binding to S1P receptors (S1PR). The present study evaluated the changes of S1PRs and investigated the potential role of S1PRs in pregnancy‑induced hypertension. PE rats were established by reduced uterine perfusion pressure. The involvement of S1PR2 was evaluated using JTE‑013, a specific S1PR2 antagonist, in PE rats. After the treatment, inflammatory cytokines were evaluated using enzyme linked immunosorbent assay, and the expression of vascular endothelial growth factor (VEGF), inducible nitric oxide synthase (iNOS) activation and endothelial nitric oxide synthase (eNOS) were evaluated by reverse transcription‑quantitative PCR and western blotting. Results showed that S1PR2, but not S1PR1 and S1PR3, was significantly increased in the serum and placenta tissues of PE rats. Notably, JTE‑013 significantly decreased blood pressure, attenuated infiltration of inflammatory cells and decreased inflammation, as indicated by the decreased expression of inflammatory cytokines, including tumor necrosis factor‑α, interleukin‑1β (IL‑1β) and IL‑6, in placental tissues. Mechanistic studies demonstrated that JTE‑013 significantly increased the expression of VEGF and decreased the expression of fms‑like tyrosine kinase 1 in placental tissue. Furthermore, JTE‑013 prevented iNOS activation and increased eNOS in placental tissue. In summary, the present study demonstrated that S1PR2 contributed to hypertension and angiogenesis imbalance in PE rats.
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http://dx.doi.org/10.3892/mmr.2021.12095DOI Listing
June 2021

Comparative Study of Three Minimally Invasive Surgical Approaches For the Treatment of L5/S1 Lumbar Intervertebral Disc Herniation.

Turk Neurosurg 2020 May 13. Epub 2020 May 13.

tianjin union medical center.

Aim: To compare the efficacy and safety of minimally endoscopic discectomy (MED), percutaneous endoscopic transforaminal endoscopic discectomy (PETD) and percutaneous endoscopic interlaminar endoscopic discectomy (PEID) in the treatment of L5/S1 lumbar disc herniation (LDH).

Material And Methods: From May 2012 to January 2017, 317 patients with L5/S1 LDH were treated with MED, PETD or PEID. Pre- and postoperative pain was measured using a visual analog scale (VAS; 0 -10), and functional status was assessed using the Oswestry Disability Index (ODI; 0 - 100%). Clinical outcomes, SF-36 scores and CK levels were compared between the 3 groups.

Results: There were 177 females and 140 males; the ages ranged from 22 to 74 years; and the course of disease was 15 to 85 days, with an average of 42.8 days.The postoperative bed rest time and average hospital stay in the MED group were higher than in the other two groups, and the differences were statistically significant.There was no significant difference in the results evaluated by the MacNab criteria. There were no significant differences in the levels of CK between the three groups before and after surgery (p 0.05).

Conclusion: Three minimally invasive surgeries for the treatment of L5/S1 LDH achieved satisfactory clinical outcomes; however, each procedure has its own advantages, disadvantages and indications. Surgeons need to choose the most appropriate surgery according to the individual condition of the patient to achieve the best therapeutic effect.
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http://dx.doi.org/10.5137/1019-5149.JTN.29539-20.2DOI Listing
May 2020

NEDD9 promotes cancer stemness by recruiting myeloid-derived suppressor cells CXCL8 in esophageal squamous cell carcinoma.

Cancer Biol Med 2021 Mar 12. Epub 2021 Mar 12.

Biotherapy Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.

Objective: Esophageal squamous cell carcinoma (ESCC) has high morbidity and mortality rates worldwide. Cancer stem cells (CSCs) may cause tumor initiation, metastasis, and recurrence and are also responsible for chemotherapy and radiotherapy failures. Myeloid-derived suppressor cells (MDSCs), in contrast, are known to be involved in mediating immunosuppression. Here, we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.

Methods: ESCC tissues and cell lines were evaluated. Neural precursor cell expressed, developmentally downregulated 9 (NEDD9) was knocked down and overexpressed by lentiviral transfection. Quantitative PCR, Western blot, immunohistochemistry, cell invasion, flow cytometry, cell sorting, multiplex chemokine profiling, and tumor growth analyses were performed.

Results: Microarray analysis revealed 10 upregulated genes in esophageal CSCs. Only NEDD9 was upregulated in CSCs using the sphere-forming method. NEDD9 expression was correlated with tumor invasion ( = 0.0218), differentiation ( = 0.0153), and poor prognosis ( = 0.0373). Additionally, NEDD9 was required to maintain the stem-like phenotype. Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8 (CXCL8) expression the ERK pathway. CXCL8 mediated the recruitment of MDSCs induced by NEDD9 and . MDSCs promoted the stemness of ESCC cells through NEDD9 the Notch pathway.

Conclusions: As a marker of ESCC, NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor, suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.
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http://dx.doi.org/10.20892/j.issn.2095-3941.2020.0290DOI Listing
March 2021

Analysis of risk factors for obstetric outcomes after hysteroscopic adhesiolysis for Asherman syndrome: A retrospective cohort study.

Int J Gynaecol Obstet 2021 Jan 23. Epub 2021 Jan 23.

Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.

Objective: To investigate the factors influencing placenta accreta in pregnant women who previously underwent hysteroscopic adhesiolysis (HA).

Methods: This retrospective study enrolled 265 women with intrauterine adhesions (IUAs) at the Sir Run Run Shaw Hospital from January 2014 to December 2018. We followed up their pregnancy outcomes and maternal complications.

Results: The menstrual pattern and gestational history before operation were significantly different between the live birth and pregnancy loss groups. The age, extent of cavity involved, type of adhesions, times of adhesiolysis performed, and time interval from surgery to pregnancy were not significantly different between these two groups. In the third trimester, 48 of 140 patients had 53 perinatal complications, including placenta accreta (27), gestational diabetes mellitus (10), pregnancy-induced hypertension (6), postpartum hemorrhage (4), intrahepatic cholestasis of pregnancy (2), placenta previa (1), oligohydramnios (1), and intrauterine growth restriction (1). Logistic regression analysis showed that extent of cavity involved and times of adhesiolysis performed were associated with placenta accreta.

Conclusion: The extent of cavity involved and times of adhesive separation surgeries were risk factors for placenta accreta in patients. The menstrual model and gestational history may provide the main predictive factors for pregnancy loss.
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http://dx.doi.org/10.1002/ijgo.13616DOI Listing
January 2021

(p)ppGpp synthetases are required for the pathogenicity of Salmonella Pullorum in chickens.

Microbiol Res 2021 Apr 5;245:126685. Epub 2021 Jan 5.

Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China; Hubei provincial key laboratory of animal pathogenic microbiology, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China. Electronic address:

Salmonella Pullorum is a pathogen specific to birds that can cause Pullorum disease in young chickens and lead to considerable economic losses in the poultry industry. During transmission and infection, S. Pullorum will encounter various environmental stresses and host defenses. The stringent response is an important adaptation response induced by (p)ppGpp, and in Salmonella, (p)ppGpp is synthesized by two (p)ppGpp synthetases, RelA and SpoT. To investigate the role of (p)ppGpp synthetases in the adaptation and pathogenicity of S. Pullorum, a (p)ppGpp synthetases mutant (ΔrelAΔspoT) was constructed, and its physiological phenotypes and pathogenicity, as well as transcription profiling, were compared with the parent strain. The ΔrelAΔspoT mutant showed decreased ability to form biofilms, and reduced resistance to acidic, alkaline, high osmolarity and HO conditions. The internalization of the ΔrelAΔspoT mutant into host cells in vitro and its lethality and colonization abilities within young chickens were also significantly reduced. RNA sequencing showed that the (p)ppGpp synthetases did not only affect the classic stringent response, such as inhibition of DNA replication and protein synthesis, but also controlled the expression of many virulence factors, in particular, the Salmonella pathogenicity island 1 (SPI-1) and SPI-2 type III secretion systems (T3SSs), and adhesion factors. These results suggest that the (p)ppGpp synthetases are required for the pathogenicity of S. Pullorum by affecting its stress response and the expression of the virulence factors.
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http://dx.doi.org/10.1016/j.micres.2020.126685DOI Listing
April 2021

A Fish Galectin-8 Possesses Direct Bactericidal Activity.

Int J Mol Sci 2020 Dec 31;22(1). Epub 2020 Dec 31.

CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.

Galectins are a family of animal lectins with high affinity for β-galactosides. Galectins are able to bind to bacteria, and a few mammalian galectins are known to kill the bound bacteria. In fish, no galectins with direct bactericidal effect have been reported. In the present study, we identified and characterized a tandem repeat galectin-8 from tongue sole (designated CsGal-8). CsGal-8 possesses conserved carbohydrate recognition domains (CRDs), as well as the conserved HXNPR and WGXEE motifs that are critical for carbohydrate binding. CsGal-8 was constitutively expressed in nine tissues of tongue sole and up-regulated in kidney, spleen, and blood by bacterial challenge. When expressed in HeLa cells, CsGal-8 protein was detected both in the cytoplasm and in the micro-vesicles secreted from the cells. Recombinant CsGal-8 (rCsGal-8) bound to lactose and other carbohydrates in a dose dependent manner. rCsGal-8 bound to a wide range of gram-positive and gram-negative bacteria and was co-localized with the bound bacteria in animal cells. Lactose, fructose, galactose, and trehalose effectively blocked the interactions between rCsGal-8 and different bacteria. Furthermore, rCsGal-8 exerted potent bactericidal activity against some gram-negative bacterial pathogens by directly damaging the membrane and structure of the pathogens. Taken together, these results indicate that CsGal-8 likely plays an important role in the immune defense against some bacterial pathogens by direct bacterial interaction and killing.
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http://dx.doi.org/10.3390/ijms22010376DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7796122PMC
December 2020

Coral gasdermin triggers pyroptosis.

Sci Immunol 2020 12;5(54)

CAS Key Laboratory of Experimental Marine Biology, Institute of Oceanology; CAS Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.

Gasdermins are executioners of the inflammatory cell death pathway pyroptosis that has so far been studied exclusively in vertebrates. In this study, we identified gasdermin E (GSDME) homologs in several invertebrate species including corals. We report that coral GSDME was cleaved by caspase 3 at two sites, yielding two active isoforms of GSDME N-terminal domain that were capable of inducing pyroptosis. Ectopic coexpression of coral GSDME and caspase 3 in human cells promoted pyroptosis. Corals infected with , a bacterial pathogen causing rapid tissue necrosis of corals worldwide, exhibited necrotic death with elevated caspase 3 activity and GSDME cleavage, whereas inhibition of caspase 3 blocked GSDME cleavage and protected corals from necrotic death. These results indicate that functional gasdermin exists in invertebrates and that coral gasdermin is involved in pathogen-induced coral death. Furthermore, our studies also suggest that mediation of pyroptosis is an evolutionarily conserved function of gasdermins.
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http://dx.doi.org/10.1126/sciimmunol.abd2591DOI Listing
December 2020

Self-Locking Stand-Alone Cage Used from Opposite Approach for the Treatment of Adjacent Segment Disease After an Anterior Cervical Corpectomy and Fusion.

Turk Neurosurg 2021 ;31(1):59-66

Tianjin Union Medical Center, Department of Spine Surgery, Tianjin 300121, China.

Aim: To investigate the efficacy and safety of the self-locking stand-alone cage used from opposite approach for the treatment of adjacent segment disease (ASD) after an anterior cervical corpectomy and fusion (ACCF).

Material And Methods: In this study, we retrospectively analyzed the clinical data of 8 cases of ACCF in the treatment of ASD cervical spondylopathy. All patients received self-locking stand-alone cage treatment. At different time points, the clinical status was evaluated using the Japan Orthopedic Association (JOA) score, JOA recovery rate (RR), and Neck Disability index (NDI) score. X-ray measurements included C2-C7 Cobb angle, fusion segment angle (FSA), cervical vertebral bow depth (VBP), and height of surgical segment (HOS). Statistical imaging parameters of sagittal cervical spine. Bone graft fusion in all self-locking stand-alone cage segments was evaluated.

Results: All operations were successfully completed, and no infection, epidural hematoma, or rupture of the dura mater were observed in all patients. Compared with pre-operation, the JOA and NDI scores at 3 months and at the last follow-up were significantly improved (p < 0.05). The JOA recovery rate between the final follow-up and preoperatively was 64.8±5.2%. One patient had dysphagia postoperatively, but was resolved after 3 months. Three months after surgery, the sagittal radiographic outcomes improved significantly and were well maintained during the final follow-up.

Conclusion: The self-locking stand-alone cage is a reliable and effective method used from the opposite approach for the treatment of ASD after ACCF in terms of JOA and NDI scores. The cervical alignment correction is considered satisfactory.
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http://dx.doi.org/10.5137/1019-5149.JTN.29575-20.3DOI Listing
March 2021

Effects of green tea extract combined with brisk walking on lipid profiles and the liver function in overweight and obese men: A randomized, double-blinded, placebo-control trial.

An Acad Bras Cienc 2020 16;92(4):e20191594. Epub 2020 Nov 16.

Kyushu University, Faculty of Human-Environment Studies, 744 Motooka, Nishi-ku, 8190395, Fukuoka City, Japan.

This study was aimed to investigate the effect of green tea extract (GTE) combined with brisk walking on lipid profiles and the liver function in overweight and obese men. Twenty-four participants were randomized to either the GTE group or the placebo group for 12 weeks with a 4-week follow-up. The walking program consisted of four 60-min-sessions/week and all participants were asked to consume two GTE (150mg) or placebo tablets daily. After 12-week intervention, GTE group resulted in a significant difference in the low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels when compared to placebo group (P < 0.01). There was also a significant reduction in the aspartate aminotransferase levels (P < 0.01) in the GTE group, but no change in the placebo group (P >0.05). There was no change in the triglyceride or high-density lipoprotein cholesterol (HDL-C) levels in the placebo group, but a significant reduction was noted in the HDL-C levels in the GTE group (P < 0.05). GTE combined with brisk walking resulted in a significant change in the LDL-C and TC levels, however, a significant reduce in HDL-C in the GTE group. The study has a more positive effect on the liver function than brisk walking alone.
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http://dx.doi.org/10.1590/0001-3765202020191594DOI Listing
November 2020

Formation and transformation of manganese(III) intermediates in the photochemical generation of manganese(IV) oxide minerals.

Chemosphere 2021 Jan 22;262:128082. Epub 2020 Aug 22.

Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China. Electronic address:

As important natural oxidants and adsorbents, manganese (Mn) oxide minerals affect the speciation, bioavailability and fate of pollutants and nutrient elements. It was found that birnessite-type Mn(IV) oxide minerals can be formed in the presence of NO and solar irradiation. However, the photochemical formation and transformation processes from Mn to Mn(IV) oxide minerals remain unclear. In this work, the Mn(IV) oxide minerals were confirmed to be photochemically formed mainly due to the disproportionation of Mn(III) intermediates generated from the oxidation of Mn in the presence of NO under UV light irradiation. The oxidation rate of Mn to Mn(IV) oxide minerals decreased with increasing initial Mn concentration due to the lower disproportionation rate. The increase in NO concentration, pH and temperature promoted Mn photochemical oxidation. The photochemical formation rate of Mn(IV) oxide minerals increased with increasing ligand concentrations at low ligand concentrations. Ligands affected the formation of Mn(IV) oxide minerals by promoting the formation and reducing the reactivity of Mn(III) intermediates. Overall, this work reveals the important role of Mn(III) intermediates in the formation of natural Mn oxide minerals.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128082DOI Listing
January 2021

Bilirubin Can Be Used as a Prognostic Factor for Lung Adenocarcinoma Patients with EGFR Mutations.

Onco Targets Ther 2020 29;13:11089-11095. Epub 2020 Oct 29.

Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People's Republic of China.

Background And Objectives: Non-small cell lung cancer (NSCLC) patients with an epidermal growth factor receptor () mutation demonstrate only a median progression-free survival (PFS) of 8 to 10 months and undergo EGFR tyrosine kinase inhibitors (EGFR-TKIs) therapy. For decades, bilirubin has been reported to be associated with the onset and prognosis of lung cancer as a prooxidant. This study aimed to investigate the prediction of pretreatment circulating bilirubin for PFS in lung adenocarcinoma (LAC) patients who underwent EGFR-TKIs targeted therapy.

Patients And Methods: LAC cases diagnosed and undergone EGFR-TKIs targeted therapy at The First Affiliated Hospital of Zhengzhou University between 2013 and 2015 were retrospectively reviewed. A total of 180 patients were studied according to inclusion and exclusion criteria. Follow-up data were collected for all patients until the disease progressed.

Results: Univariate analysis showed that the levels of pretreatment total bilirubin (TBIL), indirect bilirubin (IBIL) and direct bilirubin (DBIL) were related to PFS (all <0.05). Considering the close relationship among the three factors, we combined TBIL, IBIL and DBIL into one total factor, which is called bilirubin. Kaplan-Meier survival curves and Log rank tests indicated that patients with lower bilirubin levels had a shorter median PFS than those with higher bilirubin levels (8 vs. 15 months; 0.002). Multivariate analysis demonstrated that pretreatment bilirubin is an independent prognostic factor (HR=0.454, CI: 0.267-0.773, 0.004).

Conclusion: This study confirms that bilirubin can predict the prognosis of LAC patients who had undergone EGFR-TKIs targeted therapy.
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http://dx.doi.org/10.2147/OTT.S266477DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7605630PMC
October 2020

Regulation of (p)ppGpp and Its Homologs on Environmental Adaptation, Survival, and Pathogenicity of Streptococci.

Front Microbiol 2020 25;11:1842. Epub 2020 Sep 25.

State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.

Most streptococci are commensals, pathogens, or opportunistic pathogens for humans and animals. Therefore, it is important for streptococci to adapt to the various challenging environments of the host during the processes of infection or colonization, as well as to conditions for transmission. Stringent response (SR) is a special class of adaptive response induced by the signal molecules (p)ppGpp, which regulate several physiological aspects, such as long-term persistence, virulence, biofilm formation, and quorum sensing in bacteria. To understand the roles of SR in streptococci, the current mini-review gives a general overview on: (1) (p)ppGpp synthetases in the genus of , (2) the effects of (p)ppGpp on the physiological phenotypes, persistence, and pathogenicity of streptococci, (3) the transcriptional regulation induced by (p)ppGpp in streptococci, and (4) the link between (p)ppGpp and another nutrient regulatory protein CodY in streptococci.
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http://dx.doi.org/10.3389/fmicb.2020.01842DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7545056PMC
September 2020

Expressions of Fib, IL-12 in Serum of Neonatal Necrotizing Enterocolitis and Their Correlation with Clinicopathological Features.

Iran J Public Health 2020 Aug;49(8):1439-1446

Department of Emergency Medicine, Xuzhou Children's Hospital, Xuzhou Medical University, Xuzhou 221006, P.R. China.

Background: To investigate the expressions of fibrinogen (Fib) and Interleukin-12 (IL-12) in serum of neonatal necrotizing enterocolitis (NEC), and to analyze the correlation between the two and their relationship with clinicopathological features.

Methods: Forty two children with NEC treated in Xuzhou Children's Hospital, Xuzhou Medical University Xuzhou, China from 2016-2019 were selected as an observation group and 40 children who underwent physical examination at the same period as a control group. The expression levels of Fib and IL-12 in the serum of two groups were detected by ELISA. The correlation between Fib and IL-12 in the observation group and the correlation among the expressions of Fib, IL-12, the clinicopathological features and common examination indexes of the children with NEC were investigated by Pearson correlation analysis.

Results: The levels of Fib and IL-12 in the serum of the children in observation group were significantly higher than those in the control group were (<0.05). There was a significant positive correlation between the levels of Fib and IL-12 in the serum of the children in observation group (<0.05). The expression levels of Fib, IL-12 were not significantly correlated with sex and age of NEC children, but correlated with vomiting, diarrhea, bloody stool and bradycardia in NEC children (<0.05). Fib and IL-12 were positively correlated with erythrocyte level (<0.05) and negatively correlated with platelet level.

Conclusion: The expressions of Fib and IL-12 in the serum of NEC children can objectively predict the severity of NEC.
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http://dx.doi.org/10.18502/ijph.v49i8.3874DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7554385PMC
August 2020

Durability of neutralizing antibodies and T-cell response post SARS-CoV-2 infection.

Front Med 2020 Dec 5;14(6):746-751. Epub 2020 Oct 5.

Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.

The ongoing pandemic of Coronavirus disease 19 (COVID-19) is caused by a newly discovered β Coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). How long the adaptive immunity triggered by SARS-CoV-2 can last is of critical clinical relevance in assessing the probability of second infection and efficacy of vaccination. Here we examined, using ELISA, the IgG antibodies in serum specimens collected from 17 COVID-19 patients at 6-7 months after diagnosis and the results were compared to those from cases investigated 2 weeks to 2 months post-infection. All samples were positive for IgGs against the S- and N-proteins of SARS-CoV-2. Notably, 14 samples available at 6-7 months post-infection all showed significant neutralizing activities in a pseudovirus assay, with no difference in blocking the cell-entry of the 614D and 614G variants of SARS-CoV-2. Furthermore, in 10 blood samples from cases at 6-7 months post-infection used for memory T-cell tests, we found that interferon γ-producing CD4 and CD8 cells were increased upon SARS-CoV-2 antigen stimulation. Together, these results indicate that durable anti-SARS-CoV-2 immunity is common in convalescent population, and vaccines developed from 614D variant may offer protection from the currently predominant 614D variant of SARS-CoV-2.
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http://dx.doi.org/10.1007/s11684-020-0822-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533664PMC
December 2020

An interactive network of alternative splicing events with prognostic value in geriatric lung adenocarcinoma via the regulation of splicing factors.

Biosci Rep 2020 10;40(10)

Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 455002, Henan, China.

Alternative splicing (AS), an essential process for the maturation of mRNAs, is involved in tumorigenesis and tumor progression, including angiogenesis, apoptosis, and metastasis. AS changes can be frequently observed in different tumors, especially in geriatric lung adenocarcinoma (GLAD). Previous studies have reported an association between AS events and tumorigenesis but have lacked a systematic analysis of its underlying mechanisms. In the present study, we obtained splicing event information from SpliceSeq and clinical information regarding GLAD from The Cancer Genome Atlas. Survival-associated AS events were selected to construct eight prognostic index (PI) models. We also constructed a correlation network between splicing factors (SFs) and survival-related AS events to identify a potential molecular mechanism involved in regulating AS-related events in GLAD. Our study findings confirm that AS has a strong prognostic value for GLAD and sheds light on the clinical significance of targeting SFs in the treatment of GLAD.
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http://dx.doi.org/10.1042/BSR20202338DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7569206PMC
October 2020

Thymosin alpha-1 blocks the accumulation of myeloid suppressor cells in NSCLC by inhibiting VEGF production.

Biomed Pharmacother 2020 Nov 14;131:110740. Epub 2020 Sep 14.

Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China. Electronic address:

Background: Thymosin alpha-1 (TA) has been reported to inhibit tumor growth as an immunomodulator. However, its mechanism of action in immunosuppressive cells is unclear. The purpose of this study was to investigate whether TA can reshape the immune microenvironment by inhibiting the function of myeloid-derived suppressor cells (MDSCs) in non-small cell lung carcinoma (NSCLC).

Methods: The effects of TA on peripheral blood monocytic MDSCs (M-MDSCs) in patients with NSCLC and on the apoptosis and migration of M-MDSCs were studied. A mouse subcutaneous xenograft tumor model was constructed, and the effect of TA on M-MDSC migration was evaluated. Quantitative real-time PCR, Western blotting, flow cytometry and immunohistochemistry were used to examine the mechanism by which TA affects M-MDSCs.

Results: TA not only promoted the apoptosis of M-MDSCs by reducing the Bcl-2/BAX ratio but also and more importantly inhibited the migration of MDSCs to the tumor microenvironment by suppressing the production of vascular endothelial growth factor (VEGF) through the downregulation of hypoxia-inducible factor (HIF)-1α in tumor cells.

Conclusions: TA may have a novel antitumor effect mediated by decreasing M-MDSC accumulation in the tumor microenvironment through reduced VEGF production.
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http://dx.doi.org/10.1016/j.biopha.2020.110740DOI Listing
November 2020

Mineralized Hydrogels Induce Bone Regeneration in Critical Size Cranial Defects.

Adv Healthc Mater 2021 02 16;10(4):e2001101. Epub 2020 Sep 16.

Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA.

Sequential mineralization enables the integration of minerals within the 3D structure of hydrogels. Hydrolyzed collagen-based hydrogels are sequentially mineralized over 10 cycles. One cycle is defined as an incubation period in calcium chloride dihydrate followed by incubation in sodium phosphate dibasic dihydrate. Separate cycles are completed at 30-minute and 24-hour intervals. For the gels mineralized for 30 min and 24 h, the compressive moduli increases from 4.25 to 87.57 kPa and from 4.25 to 125.47 kPa, respectively, as the cycle number increases from 0 to 10. As indicated by X-ray diffraction (XRD) and Fourier transform infrared analysis (FTIR) analyses, the minerals in the scaffolds are mainly hydroxyapatite. In vitro experiments, which measure mechanical properties, porous structure, mineral content, and gene expression are performed to evaluate the physical properties and osteoinductivity of the scaffolds. Real time-quantitative polymerase chain reaction (RT-qPCR) demonstrates 4-10 fold increase in the expression of BMP-7 and osteocalcin. The in vivo subcutaneous implantation demonstrates that the scaffolds are biocompatible and 90% biodegradable. The critical size cranial defects in vivo exhibit nearly complete bone regeneration. Cycle 10 hydrogels mineralized for 24 h have a volume of 59.86 mm and a density of 1946.45 HU. These results demonstrate the suitability of sequentially mineralized hydrogel scaffolds for bone repair and regeneration.
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http://dx.doi.org/10.1002/adhm.202001101DOI Listing
February 2021

Survival Profile and Prognostic Factors for Appendiceal Mixed Neuroendocrine Non-neuroendocrine Neoplasms: A SEER Population-Based Study.

Front Oncol 2020 12;10:1660. Epub 2020 Aug 12.

Department of Gastroenterology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.

Introduction: Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare form of neuroendocrine neoplasms (NENs). The purpose of this study was to investigate the characteristics and survival profile of appendiceal MiNENs, with a view of providing robust clinical features of this rare disease.

Methods: Patients were selected from the Surveillance, Epidemiology, and End Results database (2004-2016). The prognosis of MiNEN ( = 315) was compared with other histological subtypes including neuroendocrine tumor (NETs) ( = 1734), neuroendocrine carcinoma (NECs) ( = 375), goblet cell carcinoid (GCC) ( = 968), signet ring cell carcinoma ( = 463), mucinous adenocarcinoma (MAC) ( = 2355), and non-mucinous adenocarcinoma (NMAC) ( = 1187) in the appendix. Age-adjusted incidence was calculated using Joinpoint regression. The Cox proportional hazards model and the Fine-Gray competing risk model were used to perform overall survival (OS) and cancer-specific mortality (CSM) analyses, respectively.

Results: The age-adjusted incidence of MiNENs increased from 0.01/100,000 person-years in 2004 to 0.07/100,000 person-years in 2016. The 3-, 5-, and 10-year OS rates for MiNENs were 69.5, 57.4, and 43.7%, respectively, and the corresponding CSM rates were 23.1, 36.4, and 45.1%, respectively. Multivariate analysis revealed that the prognosis of MiNENs was worse than that of NETs, NECs, GCC, and MAC but better than that of NMAC and signet ring cell carcinoma. Tumor extension was the only independent factor influencing the prognosis of MiNENs, but tumor size, grade, and surgical approaches were not. Moreover, when compared with local excision or appendectomy, extensive surgery such as hemicolectomy or colectomy did not prolong the survival of individuals with MiNENs.

Conclusion: MiNEN is a rare but aggressive tumor with a poor prognosis differing from NENs, GCC and adenocarcinomas. To improve the prognosis of the disease, early diagnosis and comprehensive evaluation are necessary.
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http://dx.doi.org/10.3389/fonc.2020.01660DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7438709PMC
August 2020

Characterization of Salmonella spp. isolated from chickens in Central China.

BMC Vet Res 2020 Aug 20;16(1):299. Epub 2020 Aug 20.

Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China.

Background: Salmonella is an important zoonotic pathogen, and chickens are one of its main hosts. Every year, Salmonella infections pose a serious threat to the poultry industry in developing countries, especially China. In this study, a total of 84 Salmonella isolates recovered from sick and healthy-looking chickens in central China were characterized by serotyping, MLST-based strain typing, presence of potential virulence factors, and antimicrobial resistance profiles.

Result: Data showed that the main serotypes of Salmonella isolates in central China were Salmonella enterica serovar Gallinarum biovar Pullorum, Salmonella enterica serovar Gallinarum biovar Gallinarum, Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Typhimurium, and among them, S. Pullorum was the dominant type in both sick and healthy-looking chickens, accounting for 43.9 and 46.5%, respectively, while S. Enteritidis was only found in healthy-looking chickens. All isolates exhibited higher resistance rates to ampicillin (97.6%), tetracycline (58.3%) and colistin (51.2%), and among these isolates, 49.5% were resistant to more than three drugs in different combinations. S. Enteritidis was the most severe multidrug-resistant serotype, which showed higher resistance rates to colistin, meropenem and ciprofloxacin. Multilocus sequence typing (MLST) revealed that S. Gallinarum and S. Enteritidis isolates were clustered in clade 1, which belonged to two and one STs, respectively. All S. Typhimurium isolates were clustered in clade 3, and belonged to three STs. However, S. Pullorum were distributed in three clades, which belonged to 7 STs. Twenty-seven virulence-associated genes were detected, and expected cdtB, which was absent in all the isolates, the other 26 genes were conserved in the closely related Salmonella serogroup D (S. Enteritidis, S. Pullorum, and S. Gallinarum).

Conclusion: Salmonella serogroup D was the major subgroup, and S. Pullorum was the most common type in sick and healthy-looking chickens in central China. Drug resistance assays showed serious multiple antimicrobial resistances, and S. Enteritidis was the most severe drug-resistant serotype. MLST showed that there was correlation between serotypes and genotypes in most Salmonella isolates, except S. Pullorum, which showed complicated genetic diversity firstly. These results provide important epidemiological information for us to control Salmonella in chickens.
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http://dx.doi.org/10.1186/s12917-020-02513-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7441611PMC
August 2020

Microstructure and Wear Behavior of In-Situ NbC Reinforced Composite Coatings.

Materials (Basel) 2020 Aug 5;13(16). Epub 2020 Aug 5.

School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China.

In the present study, plasma spray welding was used to prepare an in-situ niobium carbide (NbC) reinforced Ni-based composite coating on the low carbon steel, and the phase composition and the microstructure of the composite coatings were studied. The wear resistance and the wear mechanism of the composite coatings were also researched by the wear tests. The results showed that the main phases of the composite coating were NbC, γ-Ni, CrC, NiSi, CrB, CrB, CrC and FeNi. A number of fine in-situ NbC particles and numerous chromium carbide particles were distributed in the γ-Ni matrix. The increase in the mass fraction of Nb and NiCr-CrC could lead to the increase in NbC particles in the composite coatings. Due to the high hardness of NbC and chromium carbides, the micro-hardness and the wear resistance of the composite coatings were advanced. The composite coating with the powder mixtures of 20% (Nb + NiCr-CrC) and 80% NiCrBSi had the highest micro-hardness and the best wear resistance in this study. The average micro-hardness reached the maximum value 1025HV. The volume loss was 39.2 mm, which was merely 37% of that of the NiCrBSi coating and 6% of that of the substrate under the identical conditions.
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http://dx.doi.org/10.3390/ma13163459DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7475928PMC
August 2020

Evaluation of young chickens challenged with aerosolized Pullorum.

Avian Pathol 2020 Oct 17;49(5):507-514. Epub 2020 Aug 17.

Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, People's Republic of China.

serovar Pullorum (. Pullorum) is an important pathogen specific to avian species, which poses a serious threat to the poultry industry. The transmission of . Pullorum occurs both horizontally and vertically but the airborne transmission of . Pullorum has been neglected historically. In this study, the effects of aerosolized . Pullorum on young chickens were investigated. The results showed that the colonization and morbidity induced by bioaerosol infection are dose dependent. The bacteria colonized in chicken lung for more than 14 days following the exposure to ≥ 1.25 × 10 CFU/m of aerosolized . Pullorum. Tachypnoea and depression were present in all the chickens between 5 and 7 days after infection, and some died, following the exposure to ≥1.25 × 10 CFU/m of aerosolized . Pullorum. RT-PCR results showed that significant expressions of inflammatory cytokines, including tumour necrosis factor α, interleukin 1β (IL-1β), IL-6, and IL-8 were noted in the lung and spleen. Histopathological examination showed lung swelling, with obvious lesions, including inflammatory cell infiltration, tissue injury, and acute haemorrhage. These results suggest that uncontrolled and detrimental inflammation is caused by a high dose of aerosolized . Pullorum. These results further extend our understanding of the pathogenicity of air-transmitted . Pullorum on chickens. Aerosolized . Pullorum caused tachypnoea, depression, and lung swelling in chickens. The colonization and morbidity caused by aerosolized . Pullorum are dose dependent. Detrimental inflammation is caused by high doses of aerosolized . Pullorum in lung.
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http://dx.doi.org/10.1080/03079457.2020.1783433DOI Listing
October 2020

The correlation between imaging expression of P16 and S100 in hypertrophic ligamentum flavum.

BMC Musculoskelet Disord 2020 Jun 8;21(1):359. Epub 2020 Jun 8.

Department of Spine Surgery, Tianjin Union Medical Center, Tianjin, 300121, China.

Background: Lumbar spinal stenosis (LSS) is a common degenerative disease, which can lead to neurological dysfunction and requires surgical treatment. In the previous study, we used H&E staining and immunohistochemistry to qualitatively analyze the expression of S100 and P16 in the pathological process of ligamentum flavum (LF) hypertrophy in patients with LSS. To further explore the relationship between P16, S100 and LF hypertrophy in patients with LSS, we quantitatively detected S100 and P16 and their expressed products based on molecular biology techniques, and analyzed their imaging correlation.

Methods: Before posterior lumbar surgery, LF thickness was measured by Magnetic Resonance Imaging (MRI). Through the operation, we obtained the specimens of LF from 120 patients, all of whom were L4/5 LF. They were designated: simple lumbar disc herniation (LDH), single-segment spinal stenosis (SLSS), and double-segment LSS (DLSS). The detection of each side of LF was assessed. S100 and P16 and their expression products were detected by western blot and quantitative polymerase chain reaction (qPCR).

Results: The dorsal mRNA expression of P16 in DLSS group was significantly higher than that in SLSS group. On the dorsal and dural side of LF, the expression of P16 mRNA and proteins in the LDH group was significantly lower than that in SLSS and DLSS groups. We found a correlation between the thickness of LF and the expression of P16. However, there was no significant difference in the expression of S100 mRNA and S100 protein on both sides of the ligament and among the three groups, and no significant correlation between the expression of S100 and the thickness of LF.

Conclusions: P16 is involved in the process of LF hypertrophy in patients with LSS, and the imaging thickness of LF is related to the expression of P16. No obvious evidence proves that S100 may be related to the hypertrophy of LF in patients with LSS.
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http://dx.doi.org/10.1186/s12891-020-03395-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7282051PMC
June 2020

In-ovo Newcastle disease virus vaccine strain TS09-C protects commercial chickens against Newcastle disease in the presence of maternally derived antibodies.

Poult Sci 2020 May 20;99(5):2438-2443. Epub 2020 Mar 20.

Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan, China; Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture), Wuhan, China; Hubei Key Laboratory of Animal Embryo and Molecular Breeding, Wuhan, China. Electronic address:

Maternally derived antibodies (MDA) substantially interfere with active immunity in post-hatch vaccination, although they provide early protection against disease through passive immunity in young chickens. Previously, Newcastle disease virus (NDV) strain TS09-C was demonstrated to be safe and immunogenic as in-ovo vaccine in specific-pathogen-free chickens. Here, we evaluated the safety, protective efficacy, and duration of clinical protection of the TS09-C virus as an in-ovo vaccine for commercial chickens in the presence of Maternally derived antibodies against NDV. This vaccine was safe in commercial chickens and provided at least 80% protection against a virulent NDV challenge for 3 mo, despite inducing a low hemagglutinin-inhibition titer. For commercial chickens, the protective efficacy of the in-ovo vaccination was markedly higher than that of posthatch vaccination, and the cellular immune response might play an important role in the higher protective efficacy of the in-ovo vaccine. The overall results indicate that the maternally derived antibodies against NDV do not significantly interfere with the ability of the in-ovo vaccine strain TS09-C to induce protective cellular immunity.
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http://dx.doi.org/10.1016/j.psj.2020.01.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7597455PMC
May 2020

Numerical investigation of gaseous pollutant cross-transmission for single-sided natural ventilation driven by buoyancy and wind.

Build Environ 2020 Apr 31;172:106705. Epub 2020 Jan 31.

Department of Mechanical & Aerospace Engineering, University at Buffalo, 339 Jarvis Hall, Buffalo, NY, 14260, USA.

Single-sided natural ventilation was numerically investigated to determine the impact of buoyancy and wind on the cross-transmission of pollution by considering six window types commonly found in multistory buildings. The goal of this study was to predict the gaseous pollutant transmission using computational fluid dynamics based on the Reynolds-averaged Navier-Stokes equations and baseline - turbulence equations. The results indicated that ventilation rates generally increased with increasing wind speeds if the effects of buoyancy and wind were not suppressed; however, the re-entry ratio representing the proportion of expelled air re-entering other floors and the corresponding risk of infection decreased. If the source of the virus was on a central floor, the risk of infection was the highest on the floors closest to the source. Different window types were also considered for determining their effectiveness in controlling cross-transmission and infection risk, depending on the source location and driving force (e.g., buoyancy and wind).
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http://dx.doi.org/10.1016/j.buildenv.2020.106705DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7116971PMC
April 2020

Lanthanum-Modified MCF-Derived Nickel Phyllosilicate Catalyst for Enhanced CO Methanation: A Comprehensive Study.

ACS Appl Mater Interfaces 2020 Apr 19;12(17):19587-19600. Epub 2020 Apr 19.

Key Laboratory of Low Carbon Energy and Chemical Engineering, Shandong University of Science and Technology, Qingdao 266590, China.

For the traditional preparation method, it is challenging to fabricate a supported nickel catalyst with fine size at high loading. In this work, a group of La-modified mesostructured cellular foam (MCF)-derived nickel phyllosilicates was designed and synthetized by a hydrothermal method followed by an impregnation-modification of LaO, whose Ni contents varied from 25.3 to 32.2 wt %. Both the special property of phyllosilicate and the addition of a LaO modifier played significant roles in achieving high Ni dispersion and excellent catalytic performance. The formed nickel phyllosilicate was beneficial to obtain small Ni nanoparticles (<5 nm) due to its strong metal-support interaction and high specific surface area; the addition of the LaO modifier could further reduce the Ni particle size and decrease the reduction difficulty of the fabricated samples. On the contrary, a large Ni particle size of 13.0 nm was observed on the impregnated Ni/MCF (N/M-Im) catalyst with a Ni content of 31.7 wt %. As a result, the nickel phyllosilicate catalyst showed higher catalytic activity than the impregnated one, and the La modifier could further improve the catalytic activity especially at low temperature (<400 °C). Among all catalysts, the modified phyllosilicate catalyst N/M-P-32-5L with 180 °C-32 h-hydrothermal treatment and LaO content of 5 wt % was the best owing to its small-sized Ni particles, high H and CO chemisorption capacity, large turnover frequency (TOF) value, and low activation energy of 69.83 kJ mol. In addition, the intermediates of formate and CO were detected through in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis. In a 100 h-lifetime test under harsh conditions and 600 °C-steam treatment, N/M-P-32-5L showed both high sintering resistance of Ni particles and high thermal stability without the collapse of pores as well as decrease of catalytic activity, which was attributed to the special physical and chemical properties of MCF-derived nickel phyllosilicate, strong metal-support interaction over the catalyst, and the promotion of the LaO modifier.
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http://dx.doi.org/10.1021/acsami.0c03243DOI Listing
April 2020

Point Deletion or Insertion in CmeR-Box, A2075G Substitution in 23S rRNA, and Presence of (B) Are Key Factors of Erythromycin Resistance in and Isolated From Central China.

Front Microbiol 2020 3;11:203. Epub 2020 Mar 3.

Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, China.

and are major food-borne pathogens that cause bacterial gastroenteritis in humans, and poultry is considered as their most important reservoir. Macrolides, such as erythromycin, are the first-line choice for treatment of campylobacteriosis. In this study, of the 143 isolates recovered from poultry in central China during 2015-2017, 25.2% were erythromycin resistant. A2075G substitution in 23S ribosomal RNA (rRNA) and ribosomal methylase encoded by (B) were found in 4.2 and 4.9% isolates, respectively, and correlated with erythromycin resistance. The polymorphisms of CmeR-Box were also analyzed in our isolates. Among them, 9.1% isolates harbored a point deletion or insertion within the CmeR-Box, and we first showed that point deletion or insertion, but not substitution, in CmeR-Box led to high expression of , which was significantly associated with erythromycin resistance ( < 0.05). These results suggest that point deletion or insertion in CmeR-Box, A2075G substitution in 23S rRNA, and presence of (B) are three main factors to erythromycin resistance in and .
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http://dx.doi.org/10.3389/fmicb.2020.00203DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7062675PMC
March 2020

High concentration of coagulase-negative staphylococci carriage among bioaerosols of henhouses in Central China.

BMC Microbiol 2020 Jan 28;20(1):21. Epub 2020 Jan 28.

Key laboratory of prevention and control agents for animal bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China.

Background: Coagulase-negative staphylococci (CoNS) are a group of opportunistic pathogens, which are widely spread in the environment. Animal breeding is an important source of pathogen spreading. However, the concentration and characteristics of CoNS in the bioaerosols of henhouses are unclear.

Results: In this study, we showed that CoNS were significantly increased in bioaerosols of henhouses during the first 60 days, and reached 2.0 × 10 CFU/m, which account for 75.4% of total bacteria. One hundred and two CoNS isolates from bioaerosols and nasal swabs of farmers were further identified, covering seven species. Among these, 41.2% isolates were Staphylococcus sciuri, which was the predominant species, followed by S. equorum, S. saprophyticus, S. haemolyticus, S. xylosus, S. arlettae and S. gallinarum. There were high rates of resistance to oxacillin in CoNS (49.0%), which were defined as Methicillin-Resistant CoNS (MRCoNS), and 36.3% isolates contained resistance gene mecA. Bioaerosol infection models showed that, chickens exposed to aerosolized S. sciuri had significant induction of inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8 and IL-10 at 5 days post-infection (dpi) in lungs and at 7 dpi in spleens.

Conclusions: We reported a high concentration of CoNS in henhouses, and S. sciuri was the preponderant CoNS species. Antibiotic resistance analysis and bioaerosols infection of CoNS further highlighted its hazards on resistance and immunological challenge. These results suggested that, CoNS in bioaerosols could be one serious factor in the henhouses for not only poultry industry but also public health.
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http://dx.doi.org/10.1186/s12866-020-1709-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6986044PMC
January 2020

Catechol-functionalized hydrogels: biomimetic design, adhesion mechanism, and biomedical applications.

Chem Soc Rev 2020 Jan 15;49(2):433-464. Epub 2020 Jan 15.

Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931, USA.

Hydrogels are a unique class of polymeric materials that possess an interconnected porous network across various length scales from nano- to macroscopic dimensions and exhibit remarkable structure-derived properties, including high surface area, an accommodating matrix, inherent flexibility, controllable mechanical strength, and excellent biocompatibility. Strong and robust adhesion between hydrogels and substrates is highly desirable for their integration into and subsequent performance in biomedical devices and systems. However, the adhesive behavior of hydrogels is severely weakened by the large amount of water that interacts with the adhesive groups reducing the interfacial interactions. The challenges of developing tough hydrogel-solid interfaces and robust bonding in wet conditions are analogous to the adhesion problems solved by marine organisms. Inspired by mussel adhesion, a variety of catechol-functionalized adhesive hydrogels have been developed, opening a door for the design of multi-functional platforms. This review is structured to give a comprehensive overview of adhesive hydrogels starting with the fundamental challenges of underwater adhesion, followed by synthetic approaches and fabrication techniques, as well as characterization methods, and finally their practical applications in tissue repair and regeneration, antifouling and antimicrobial applications, drug delivery, and cell encapsulation and delivery. Insights on these topics will provide rational guidelines for using nature's blueprints to develop hydrogel materials with advanced functionalities and uncompromised adhesive properties.
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http://dx.doi.org/10.1039/c9cs00285eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7208057PMC
January 2020

Draft Genome Sequences of Multidrug-Resistant Campylobacter jejuni Strains Isolated from Chickens in Central China.

Microbiol Resour Announc 2020 Jan 2;9(1). Epub 2020 Jan 2.

Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, China

is a major foodborne pathogen that plays an important role in spreading drug resistance. We report the draft genome sequences of two multidrug-resistant isolates which contained similar mutations in the CmeR box. This will improve the understanding of antimicrobial resistance and genetic characteristics.
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http://dx.doi.org/10.1128/MRA.01303-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6940295PMC
January 2020