Publications by authors named "Zhen Jin"

336 Publications

Laser-assisted hatching in lower grade cleavage stage embryos improves blastocyst formation: results from a retrospective study.

J Ovarian Res 2021 Jul 15;14(1):94. Epub 2021 Jul 15.

Department of Reproductive Endocrinology, Zhejiang Provincial People's Hospital, Hangzhou Medical College, 310000, Hangzhou, P.R. China.

Background: Laser-assisted hatching (LAH) has been widely applied to facilitate blastocyst hatching in IVF-ET treatment, however, the effect of LAH on subsequent development and clinical outcomes of the lower grade cleavage stage embryos (LGCE) remains unknown. Our study aimed at evaluating the effect of LAH on blastocyst formation and the clinical pregnancy outcomes of LGCE embryos after transfer.

Methods: A total of 608 cycles of IVF/ICSI treatment from November 2017 to September 2019 were included in our study as follows: 296 in the LAH group and 312 in the N-LAH group. The total blastocyst rate, usable blastocyst rate, good-grade blastocyst rate and clinical pregnancy rate were statistically compared between the two groups.

Results: The total blastocyst rate (50.7% vs 40.2%, P < 0.001), usable blastocyst rate (31.0% vs 18.6%, P < 0.001) were significantly higher in the LAH group than those in the N-LAH group. After analysis of generalized estimating equations, LAH was positively correlated with the blastocyst rate (B = 0.201, OR 95% CI = 1.074-1.393, P = 0.002), usable blastocyst rate (B = 0.478, OR 95% CI = 1.331-1.955, P < 0.001). However, the clinical pregnancy rate after blastocyst transfer did not differ between LAH group and N-LAH group (49.4% vs 40.0%, P > 0.05, respectively).

Conclusions: A higher proportion of total blastocysts and usable blastocysts can be obtained by LAH in LGCE, which may be beneficial to the outcome of the IVF/ICSI-ET cycle.
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http://dx.doi.org/10.1186/s13048-021-00844-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8281458PMC
July 2021

The combination of targeted vaccination and ring vaccination.

Chaos 2021 Jun;31(6):063108

School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China.

Complex networks have become an important tool for investigating epidemic dynamics. A widely concerned research field for epidemics is to develop and study mitigation strategies or control measures. In this paper, we devote our attention to ring vaccination and targeted vaccination and consider the combination of them. Based on the different roles ring vaccination plays in the mixed strategy, the whole parameter space can be roughly divided into two regimes. In one regime, the mixed strategy performs poorly compared with targeted vaccination alone, while in the other regime, the addition of ring vaccination can improve the performance of targeted vaccination. This result gives us the more general and overall comparison between targeted and ring vaccination. In addition, we construct a susceptible-infected-recovered epidemic model coupled with the immunization dynamics on random networks. The comparison between stochastic simulations and numerical simulations confirms the validity of the model we propose.
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http://dx.doi.org/10.1063/5.0048457DOI Listing
June 2021

SIRT6 inhibits inflammatory response through regulation of NRF2 in vascular endothelial cells.

Int Immunopharmacol 2021 Jul 4;99:107926. Epub 2021 Jul 4.

Department of Pharmacology, Xi'an Jiaotong University, Health Science Center, Xi'an, Shaanxi 710061, China. Electronic address:

Emerging evidence suggests that inflammation plays a pivotal role in Atherosclerosis. Sirtuin 6 (SIRT6), a member of NAD-dependent protein lysine deacylases of the sirtuin family, plays an important role in the regulation of metabolism, aging and stress resistance. However, the role of SIRT6 in vascular inflammation and its molecular mechanism is unknown. The present study showed that TNF-α significantly reduced the expression of SIRT6 protein and mRNA in a concentration- and time-dependent manner and increased the expression of monocyte chemotactic protein 1 (MCP-1), interleukin (IL) -6 and IL-1β in human umbilical vein endothelial cells (HUVECs). Overexpression of SIRT6 but not its catalytically inactive mutant inhibited TNF-α-induced expression of MCP-1, IL-6 and IL-1β. Knockdown of SIRT6 significantly enhanced TNF-α-induced expression of MCP-1, IL-6 and IL-1β. Moreover, knockdown of SIRT6 reduced TNF-α-induced nuclear factor erythroid 2 related factor 2 (NRF2) nucleus protein expression, whereas knockdown of NRF2 significantly enhanced TNF-α-induced expression of MCP-1, IL-6 and IL-1β. In addition, overexpression of SIRT6 increased NRF2 and its target genes expression, and knockdown of SIRT6 decreased NRF2 and its target genes expression. Meanwhile, knockdown of SIRT6 inhibited NRF2 nucleus protein expression. Further, knockdown of SIRT6 decreased phosphorylation of NRF2, overexpression of SIRT6 increased phosphorylation of NRF2. SIRT6 interacted with NRF2. In vivo, the levels of TNF-α and IL-1β were increased in the serum of hyperlipidemia mice. Hyperlipidemia-induced production of MCP-1, IL-6 and IL-1β was significantly augmented in the endothelium specific SIRT6 knockout mice. In contrast, the expression of NRF2 and its target genes was reduced. Taken together, these results indicate that SIRT6 protects against vascular inflammation via its deacetylase activity and the NRF2-dependent signaling pathway.
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http://dx.doi.org/10.1016/j.intimp.2021.107926DOI Listing
July 2021

Antibacterial Activity of a Promising Antibacterial Agent: 22-(4-(2-(4-Nitrophenyl-piperazin-1-yl)-acetyl)-piperazin-1-yl)-22-deoxypleuromutilin.

Molecules 2021 Jun 8;26(12). Epub 2021 Jun 8.

Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.

A novel pleuromutilin derivative, 22-(4-(2-(4-nitrophenyl-piperazin-1-yl)-acetyl)-piperazin-1-yl)-22-deoxypleuromutilin (NPDM), was synthesized in our laboratory and proved excellent antibacterial activity against methicillin-resistant (MRSA). In this study, more methods were used to further study its preliminary pharmacological effect. The antibacterial efficacy and toxicity of NPDM were evaluated using tiamulin as the reference drug. The in vitro antibacterial activity study showed that NPDM is a potent bactericidal agent against MRSA that induced time-dependent growth inhibition and a concentration-dependent post-antibiotic effect (PAE). Toxicity determination showed that the cytotoxicity of NPDM was slightly higher than that of tiamulin, but the acute oral toxicity study proved that NPDM was a low-toxic compound. In an in vivo antibacterial effect study, NPDM exhibited a better therapeutic effect than tiamulin against MRSA in a mouse thigh infection model as well as a mouse systemic infection model with neutropenia. The 50% effective dose (ED) of NPDM in a infection model was 50.53 mg/kg. The pharmacokinetic properties of NPDM were also measured, which showed that NPDM was a rapid elimination drug in mice.
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http://dx.doi.org/10.3390/molecules26123502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8227856PMC
June 2021

Design, synthesis and biological evaluation of pleuromutilin-Schiff base hybrids as potent anti-MRSA agents in vitro and in vivo.

Eur J Med Chem 2021 Jun 12;223:113624. Epub 2021 Jun 12.

Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China. Electronic address:

A series of pleuromutilin derivatives with 1,2,4-triazole-3-substituted Schiff base structure were designed and synthesized under mild conditions. The in vitro antibacterial activities of the synthesized derivatives against 4 strains of Staphylococcus aureus (MRSA ATCC 43300, S.aureus ATCC 29213, S.aureus 144 and S.aureus AD3) and 1 strain of E. coli (ATCC 25922) were evaluated by the broth dilution method. Among these derivatives, compound 60 exhibited superior in vitro antibacterial effect against MRSA (MIC = 0.25 μg/mL) than tiamulin (MIC = 0.5 μg/mL), and compound 60 (-2.28 log CFU/mL) also displayed superior in vivo antibacterial efficacy than tiamulin (-1.40 log CFU/mL) in reducing MRSA load in the mouse thigh infection model. The time-kill study and the post-antibiotic effect study indicated that compound 60 showed a faster bactericidal kinetic and longer PAE time (exposure to 2 × MIC and 4 × MIC for 2 h, the PAE was 4.06 and 4.27 h) against MRSA compared with tiamulin (exposure to 2 × MIC and 4 × MIC for 2 h, the PAE was 1.72 and 2.14 h). Meanwhile, most of these compounds had no significant inhibitory effect on RAW 264.7 cells and HepG2 cells at the concentration of 4 μg/mL. Additionally, the development of resistance study showed that MRSA did not easily develop resistance against compound 60 compared with tiamulin after induction for 8 passages.
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http://dx.doi.org/10.1016/j.ejmech.2021.113624DOI Listing
June 2021

Correction: Ablation of dynamin-related protein 1 promotes diabetes-induced synaptic injury in the hippocampus.

Cell Death Dis 2021 Jun 1;12(6):565. Epub 2021 Jun 1.

Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, 52727, Republic of Korea.

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http://dx.doi.org/10.1038/s41419-021-03841-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169749PMC
June 2021

Spastin interacts with CRMP5 to promote spindle organization in mouse oocytes by severing microtubules.

Zygote 2021 May 26:1-12. Epub 2021 May 26.

Department of Gynaecology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang310014, China.

Microtubule-severing protein (MTSP) is critical for the survival of both mitotic and postmitotic cells. However, the study of MTSP during meiosis of mammalian oocytes has not been reported. We found that spastin, a member of the MTSP family, was highly expressed in oocytes and aggregated in spindle microtubules. After knocking down spastin by specific siRNA, the spindle microtubule density of meiotic oocytes decreased significantly. When the oocytes were cultured in vitro, the oocytes lacking spastin showed an obvious maturation disorder. Considering the microtubule-severing activity of spastin, we speculate that spastin on spindles may increase the number of microtubule broken ends by severing the microtubules, therefore playing a nucleating role, promoting spindle assembly and ensuring normal meiosis. In addition, we found the colocalization and interaction of collapsin response mediator protein 5 (CRMP5) and spastin in oocytes. CRMP5 can provide structural support and promote microtubule aggregation, creating transportation routes, and can interact with spastin in the microtubule activity of nerve cells (30). Knocking down CRMP5 may lead to spindle abnormalities and developmental disorders in oocytes. Overexpression of spastin may reverse the abnormal phenotype caused by the deletion of CRMP5. In summary, our data support a model in which the interaction between spastin and CRMP5 promotes the assembly of spindle microtubules in oocytes by controlling microtubule dynamics, therefore ensuring normal meiosis.
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http://dx.doi.org/10.1017/S0967199421000344DOI Listing
May 2021

Development and Validation of a Novel Prognostic Model for Acute Myeloid Leukemia Based on Immune-Related Genes.

Front Immunol 2021 5;12:639634. Epub 2021 May 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, China.

The prognosis of acute myeloid leukemia (AML) is closely related to immune response changes. Further exploration of the pathobiology of AML focusing on immune-related genes would contribute to the development of more advanced evaluation and treatment strategies. In this study, we established a novel immune-17 signature based on transcriptome data from The Cancer Genome Atlas (TCGA) and The Genotype-Tissue Expression (GTEx) databases. We found that immune biology processes and transcriptional dysregulations are critical factors in the development of AML through enrichment analyses. We also formulated a prognostic model to predict the overall survival of AML patients by using LASSO (Least Absolute Shrinkage and Selection Operator) regression analysis. Furthermore, we incorporated the immune-17 signature to improve the prognostic accuracy of the ELN2017 risk stratification system. We concluded that the immune-17 signature represents a novel useful model for evaluating AML survival outcomes and may be implemented to optimize treatment selection in the next future.
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http://dx.doi.org/10.3389/fimmu.2021.639634DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8131848PMC
May 2021

Is unilateral transverse process-pedicle percutaneous kyphoplasty a better choice for osteoporotic thoracolumbar fractures in the old patients?

BMC Surg 2021 May 21;21(1):252. Epub 2021 May 21.

Orthopedics Department, The Second Affiliated Hospital of Nanjing Medical University, Jiangjiayuan Road No. 121, Nanjing, 210000, Jiangsu Province, China.

Background: A few reports have shown that unilateral transverse process-pedicle percutaneous kyphoplasty is a good choice for patients with osteoporotic vertebral compression fracture (OVCF). However, this issue remains controversial and the related comprehensive research was lacked.

Methods: A retrospective study was conducted on patients receiving PKP surgery for OVCF. Patients were divided into three groups according to surgical approach. Symptom and radiographical evaluation were performed preoperatively, 1-month postoperatively, 1-year postoperatively and follow-ups. And follow-ups were repeated every year. Visual Analogue Scale Score (VAS), Oswestry Disability Index (ODI) scores, anterior vertebral height, coronal Cobb angle and sagittal Cobb angle was determined and compared among three groups.

Results: Totally 447 patients were included with an average age of 76.6 ± 7.2 years old. UTP showed significantly shorter surgical duration (p < 0.001), lower cement volume (p < 0.001) but higher cement leakage proportion (p = 0.044). No significant statistical difference was found in terms of improvement rates among three groups. Besides, it was notable that the a significantly higher coronal Cobb angle was observed in UTP group, and a about 4°coronal correction was found after UTP PKP.

Conclusion: UTTP PKP could achieve similar symptoms relief and kyphosis correction as UTP and BTP PKP. However, it had shorter surgical time and less radio exposure than BTP PKP, lower risk of cement leakage and higher proportion of bilaterally cement distribution than UTP PKP. It seemed to be a better choice for patients with OVCF. In addition, we found that UTP PKP was especially fit for OVCF patients with asymmetrical vertebral compression.
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http://dx.doi.org/10.1186/s12893-021-01246-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139159PMC
May 2021

Design, synthesis, in vitro and in vivo evaluation against MRSA and molecular docking studies of novel pleuromutilin derivatives bearing 1, 3, 4-oxadiazole linker.

Bioorg Chem 2021 Jul 1;112:104956. Epub 2021 May 1.

Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China. Electronic address:

A class of pleuromutilin derivatives containing 1, 3, 4-oxadiazole were designed and synthesized as potential antibacterial agents against Methicillin-resistant staphylococcus aureus (MRSA). The ultrasound-assisted reaction was proposed as a green chemistry method to synthesize 1, 3, 4-oxadiazole derivatives (intermediates 85-110). Among these pleuromutilin derivatives, compound 133 was found to be the strongest antibacterial derivative against MRSA (MIC = 0.125 μg/mL). Furthermore, the result of the time-kill curves displayed that compound 133 could inhibit the growth of MRSA in vitro quickly (- 4.36 log10 CFU/mL reduction). Then, compound 133 (- 1.82 log CFU/mL) displayed superior in vivo antibacterial efficacy than tiamulin (- 0.82 log CFU/mL) in reducing MRSA load in mice thigh model. Besides, compound 133 exhibited low cytotoxicity to RAW 264.7 cells. Molecular docking studies revealed that compound 133 was successfully localized in the binding pocket of 50S ribosomal subunit (ΔG = -10.50 kcal/mol). The results indicated that these pleuromutilin derivatives containing 1, 3, 4-oxadiazole might be further developed into novel antibiotics against MRSA.
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http://dx.doi.org/10.1016/j.bioorg.2021.104956DOI Listing
July 2021

Hydroxytyrosol Acetate Inhibits Vascular Endothelial Cell Pyroptosis via the HDAC11 Signaling Pathway in Atherosclerosis.

Front Pharmacol 2021 23;12:656272. Epub 2021 Apr 23.

Department of Pharmacology, Xi'an Jiaotong University Health Science Center, Xi'an, China.

Hydroxytyrosol acetate (HT-AC), a natural polyphenolic compound in olive oil, exerts an anti-inflammatory effect in cardiovascular diseases (CVDs). Pyroptosis is a newly discovered form of programmed inflammatory cell death and is suggested to be involved in the atherosclerosis (AS) process. However, the effect of HT-AC on vascular endothelial cell pyroptosis remains unknown. Thus, we aimed to investigate the effect of HT-AC on vascular endothelial cell pyroptosis in AS and related signaling pathways. studies showed that HT-AC alleviated the formation of atherosclerotic lesions and inhibited pyroptosis in the aortic intima of ApoE mice fed a high-fat diet (HFD) for 12 weeks. , we found that HT-AC treatment of human umbilical vein endothelial cells (HUVECs) alleviated tumor necrosis factor-alpha (TNF-α)-induced pyroptosis by decreasing the number of PI positive cells, decreasing the enhanced protein expressions of activated caspase-1 and gasdermin D (GSDMD), as well as by decreasing the release of pro-inflammatory interleukin (IL)-1β and IL-6. Besides, HT-AC down-regulated HDAC11 expression in the aortic intima of HFD-fed ApoE mice and TNF-α-stimulated HUVECs. To determine the underlying mechanism of action, molecular docking and drug affinity responsive target stability (DARTS) were utilized to identify whether HDAC11 protein is a target of HT-AC. The molecular docking result showed good compatibility between HT-AC and HDAC11. DARTS study's result showed that HDAC11 protein may be a target of HT-AC. Further study demonstrated that knockdown of HDAC11 augmented the inhibition of HT-AC on pyroptosis in TNF-α-stimulated HUVECs. These findings indicate that HT-AC might prevent vascular endothelial pyroptosis through down-regulation of HDAC11 related signaling pathway in AS.
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http://dx.doi.org/10.3389/fphar.2021.656272DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100680PMC
April 2021

Activation of acid-sensing ion channels by carbon dioxide regulates amygdala synaptic protein degradation in memory reconsolidation.

Mol Brain 2021 May 7;14(1):78. Epub 2021 May 7.

Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, 38163, Memphis, TN, USA.

Reconsolidation has been considered a process in which a consolidated memory is turned into a labile stage. Within the reconsolidation window, the labile memory can be either erased or strengthened. Manipulating acid-sensing ion channels (ASICs) in the amygdala via carbon dioxide (CO) inhalation enhances memory retrieval and its lability within the reconsolidation window. Moreover, pairing CO inhalation with retrieval bears the reactivation of the memory trace and enhances the synaptic exchange of the calcium-impermeable AMPA receptors to calcium-permeable AMPA receptors. Our patch-clamp data suggest that the exchange of the AMPA receptors depends on the ubiquitin-proteasome system (UPS), via protein degradation. Ziram (50 µM), a ubiquitination inhibitor, reduces the turnover of the AMPA receptors. CO inhalation with retrieval boosts the ubiquitination without altering the proteasome activity. Several calcium-dependent kinases potentially involved in the CO-inhalation regulated memory liability were identified using the Kinome assay. These results suggest that the UPS plays a key role in regulating the turnover of AMPA receptors during CO inhalation.
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http://dx.doi.org/10.1186/s13041-021-00786-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8106190PMC
May 2021

Ablation of dynamin-related protein 1 promotes diabetes-induced synaptic injury in the hippocampus.

Cell Death Dis 2021 May 5;12(5):445. Epub 2021 May 5.

Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, 52727, Republic of Korea.

Dynamin-related protein 1 (Drp1)-mediated mitochondrial dysfunction is associated with synaptic injury in the diabetic brain. However, the dysfunctional mitochondria by Drp1 deletion in the diabetic brain are poorly understood. Here, we investigated the effects of neuron-specific Drp1 deletion on synaptic damage and mitophagy in the hippocampus of a high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic mice. HFD/STZ-induced diabetic mice exhibited metabolic disturbances and synaptic damages. Floxed Drp1 mice were crossed with Ca/calmodulin-dependent protein kinase IIα (CaMKIIα)-Cre mice, to generate neuron-specific Drp1 knockout (Drp1cKO) mice, which showed marked mitochondrial swelling and dendritic spine loss in hippocampal neurons. In particular, diabetic Drp1cKO mice exhibited an increase in dendritic spine loss and higher levels of oxidative stress and neuroinflammation compared with diabetic wild-type (WT) mice. Diabetic WT mice generally displayed increased Drp1-induced small mitochondrial morphology in hippocampal neurons, but large mitochondria were prominently observed in diabetic Drp1cKO mice. The levels of microtubule-associated protein 1 light-chain 3 and lysosomal-associated membrane protein 1 proteins were significantly increased in the hippocampus of diabetic Drp1cKO mice compared with diabetic WT mice. The inhibition of Drp1 adversely promotes synaptic injury and neurodegeneration in the diabetic brain. The findings suggest that the exploratory mechanisms behind Drp1-mediated mitochondrial dysfunction could provide a possible therapeutic target for diabetic brain complications.
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http://dx.doi.org/10.1038/s41419-021-03723-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099876PMC
May 2021

Nonpharmaceutical interventions contribute to the control of COVID-19 in China based on a pairwise model.

Infect Dis Model 2021 10;6:643-663. Epub 2021 Apr 10.

Complex System Research Center, Shanxi University, Taiyuan, 030006, Shanxi, China.

Nonpharmaceutical interventions (NPIs), particularly contact tracing isolation and household quarantine, play a vital role in effectively bringing the Coronavirus Disease 2019 (COVID-19) under control in China. The pairwise model, has an inherent advantage in characterizing those two NPIs than the classical well-mixed models. Therefore, in this paper, we devised a pairwise epidemic model with NPIs to analyze COVID-19 outbreak in China by using confirmed cases during February 3rd-22nd, 2020. By explicitly incorporating contact tracing isolation and family clusters caused by household quarantine, our model provided a good fit to the trajectory of COVID-19 infections. We calculated the reproduction number  = 1.345 (95 CI: 1.230 - 1.460) for Hubei province and  = 1.217 (95 CI: 1.207 - 1.227) for China (except Hubei). We also estimated the peak time of infections, the epidemic duration and the final size, which are basically consistent with real observation. We indicated by simulation that the traced high-risk contacts from incubated to susceptible decrease under NPIs, regardless of infected cases. The sensitivity analysis showed that reducing the exposure of the susceptible and increasing the clustering coefficient bolster COVID-19 control. With the enforcement of household quarantine, the reproduction number and the epidemic prevalence declined effectively. Furthermore, we obtained the resumption time of work and production in China (except Hubei) on 10th March and in Hubei at the end of April 2020, respectively, which is broadly in line with the actual time. Our results may provide some potential lessons from China on the control of COVID-19 for other parts of the world.
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http://dx.doi.org/10.1016/j.idm.2021.04.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8035808PMC
April 2021

Estimation of COVID-19 outbreak size in Harbin, China.

Nonlinear Dyn 2021 Apr 10:1-9. Epub 2021 Apr 10.

School of Mathematical Sciences, Tiangong University, Tianjin, 300387 China.

Since the first level response to public health emergencies was launched on January 25, 2020, in Heilongjiang province, China, the outbreak of COVID-19 seems to be under control. However, an outbreak of COVID-19 caused by imported cases developed in Harbin during April 2020. A mathematical model is established to investigate the transmission of COVID-19 in Harbin. Based on the dynamical analysis and data fitting, the research investigates the outbreak of COVID-19 in Harbin and estimates the outbreak size of COVID-19 in Harbin. The outbreak size estimated of COVID-19 in Harbin reaches 174, where 54% of infected cases were identified while 46% of infected cases were not found out. We should maintain vigilance against unfound infected people. Our findings suggest that the effective reproduction number decreased drastically in contrast with the value of 3.6 on April 9; after that the effective interventions were implemented by the Heilongjiang province government. Finally, the effective reproduction number arrived at the value of 0.04 which is immensely below the threshold value 1, which means that the Heilongjiang province government got the outbreak of COVID-19 in Harbin under control.
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http://dx.doi.org/10.1007/s11071-021-06406-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8035889PMC
April 2021

Tumor-targeted Gd-doped mesoporous FeO nanoparticles for T/T MR imaging guided synergistic cancer therapy.

Drug Deliv 2021 Dec;28(1):787-799

School of Medical Imaging, Xuzhou Medical University, Xuzhou, China.

In this study, a novel intelligent nanoplatform to integrate multiple imaging and therapeutic functions for targeted cancer theranostics. The nanoplatform, [email protected] NPs, was constructed Gd-doped mesoporous FeO nanoparticles following with the doxorubicin (DOX) loading in the mesopores of the NPs. The [email protected] NPs exhibited good properties in colloidal dispersity, photothermal conversion, NIR triggered drug release, and high T/T relaxicity rate (=9.64 mMs, = 177.71 mMs). Benefiting from the high MR contrast, [email protected] NPs enabled simultaneous T/T dual-modal MR imagining on 4T1 bearing mice and the MR contrast effect was further strengthened by external magnetic field. In addition, the [email protected] NPs revealed the strongest inhibition to the growth of 4T1 and under NIR irradiation and guidance of external magnetic field. Moreover, biosafety was also validated by and tests. Thus, the prepared [email protected] NPs would provide a promising intelligent nanoplatform for dual-modal MR imagining guided synergistic therapy in cancer theranostics.
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http://dx.doi.org/10.1080/10717544.2021.1909177DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079076PMC
December 2021

Design, synthesis and biological evaluation of novel pleuromutilin derivatives as potent anti-MRSA agents targeting the 50S ribosome.

Bioorg Med Chem 2021 May 2;38:116138. Epub 2021 Apr 2.

Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China. Electronic address:

A series of novel pleuromutilin derivatives were designed and synthesized with 1,2,4-triazole as the linker connected to benzoyl chloride analogues under mild conditions. The in vitro antibacterial activities of the synthesized derivatives against four strains of Staphylococcus aureus (MRSA ATCC 43300, ATCC 29213, AD3 and 144) were tested by the broth dilution method. Most of the synthesized derivatives displayed potent activities, and 22-(3-amino-2-(4-methyl-benzoyl)-1,2,4-triazole-5-yl)-thioacetyl)-22-deoxypleuromutilin (compound 12) was found to be the most active antibacterial derivative against MRSA (MIC = 0.125 μg/mL). Furthermore, the time-kill curves showed compound 12 had a certain inhibitory effect against MRSA in vitro. The in vivo antibacterial activity of compound 12 was further evaluated using MRSA infected murine thigh model. Compound 12 exhibited superior antibacterial efficacy than tiamulin. It was also found that compound 12 had no significant inhibitory effect on the proliferation of RAW264.7 cells. Compound 12 was further evaluated in CYP450 inhibition assay and showed moderate inhibitory effect on CYP3A4 (IC = 3.95 μM). Moreover, seven candidate compounds showed different affinities with the 50S ribosome by SPR measurement. Subsequently, binding of compound 12 and 20 to the 50S ribosome was further investigated by molecular modeling. Three strong hydrogen bonds were formed through the interaction of compound 12 and 20 with 50S ribosome. The binding free energy of compound 12 and 20 with the ribosome was calculated to be -10.7 kcal/mol and -11.66 kcal/mol, respectively.
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http://dx.doi.org/10.1016/j.bmc.2021.116138DOI Listing
May 2021

Sensitivity assessment and optimal economic evaluation of a new COVID-19 compartmental epidemic model with control interventions.

Chaos Solitons Fractals 2021 May 20;146:110885. Epub 2021 Mar 20.

Department of Mathematics and Statistics, University of Energy and Natural Resources, Sunyani, Ghana.

Optimal economic evaluation is pivotal in prioritising the implementation of non-pharmaceutical and pharmaceutical interventions in the control of diseases. Governments, decision-makers and policy-makers broadly need information about the effectiveness of a control intervention concerning its cost-benefit to evaluate whether a control intervention offers the best value for money. The outbreak of COVID-19 in December 2019, and the eventual spread to other parts of the world, have pushed governments and health authorities to take drastic socioeconomic, sociocultural and sociopolitical measures to curb the spread of the virus, SARS-CoV-2. To help policy-makers, health authorities and governments, we propose a Susceptible, Exposed, Asymptomatic, Quarantined asymptomatic, Severely infected, Hospitalized, Recovered, Recovered asymptomatic, Deceased, and Protective susceptible (individuals who observe health protocols) compartmental structure to describe the dynamics of COVID-19. We fit the model to real data from Ghana and Egypt to estimate model parameters using standard incidence rate. Projections for disease control and sensitivity analysis are presented using MATLAB. We noticed that multiple peaks (waves) of COVID-19 for Ghana and Egypt can be prevented if stringent health protocols are implemented for a long time and/or the reluctant behaviour on the use of protective equipment by individuals are minimized. The sensitivity analysis suggests that: the rate of diagnoses and testing, the rate of quarantine through doubling enhanced contact tracing, adhering to physical distancing, adhering to wearing of nose masks, sanitizing-washing hands, media education remains the most effective measures in reducing the control reproduction number to less than unity in the absence of vaccines and therapeutic drugs in Ghana and Egypt. Optimal control and cost-effectiveness analysis are rigorously studied. The main finding is that having two controls (transmission reduction and case isolation) is better than having one control, but is economically expensive. In case only one control is affordable, then transmission reduction is better than case isolation. Hopefully, the results of this research should help policy-makers when dealing with multiple waves of COVID-19.
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http://dx.doi.org/10.1016/j.chaos.2021.110885DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7980175PMC
May 2021

Network and 16S rRNA Sequencing-Combined Approach Provides Insightal Evidence of Vitamin K for Salt-Sensitive Hypertension.

Front Nutr 2021 24;8:639467. Epub 2021 Feb 24.

College of Chinese medicine, Jinan University, Guangzhou, China.

Vitamin K (VK2), found to act to treat hypertension, has been widely used in the food and pharmaceutical industries nowadays. However, the potential targets and molecular mechanisms of VK2 for salt-sensitive hypertension have not been fully investigated. Therefore, the study aimed to investigate the potential molecular mechanisms of VK2 for salt-sensitive hypertension using network pharmacology and 16S rRNA sequencing strategy. The network pharmacology-based findings from KEGG enrichment analysis revealed that VK2-treated salt-sensitive hypertension was mechanically associated with the complement and coagulation cascades, calcium signaling pathway, renin-angiotensin system, etc. A total of 29 different bacteria in an animal experiment after VK2 supplementation were screened and functionally enriched using PICRUSt2. Additionally, 10 signaling pathways were identified in which the renin-angiotensin system was found to be the potential molecular mechanisms with the greatest change in multiple and statistical significance. Moreover, the results of the renin-angiotensin system-related protein expression exhibited VK2-inhibited renin-angiotensin system in salt-induced hypertensive mice, which significantly verified the previous biological and functional prediction analysis. Finally, spearman correlation analysis showed the different bacteria such as , etc., had a positive or negative correlation with renin-angiotensin system-related proteins in salt-induced mice. In conclusion, the potential molecular mechanisms of VK2 for salt-sensitive hypertension may be beneficially achieved by the specific inhibition of the renin-angiotensin system, contributing to the development for a new preventive strategy of salt-sensitive hypertension.
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http://dx.doi.org/10.3389/fnut.2021.639467DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943625PMC
February 2021

Protective effect of SIRT6 on cholesterol crystal-induced endothelial dysfunction via regulating ACE2 expression.

Exp Cell Res 2021 May 22;402(1):112526. Epub 2021 Feb 22.

Department of Pharmacology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, 710061, China. Electronic address:

Sirtuins are a family of highly conserved nicotinamide adenine dinucleotide (NAD)-dependent enzymes. Among the sirtuins, SIRT1 and SIRT6 participate in the regulation of endothelial functions and play significant roles in the physiological and pathological processes of cardiovascular diseases (CVD). Recently, our study found that minute cholesterol crystals (CC) can be endocytosed by endothelial cells and further impair endothelial functions. Since previous studies have reported that angiotensin-converting enzyme (ACE2) involves Angiotensin (Ang) II-induced inflammation in endothelial cells, this study was designed to investigate the role of SIRT1 and SIRT6 in CC-induced variation of ACE2 expression and the related mechanism between SIRT6 and ACE2. We found that ACE2 is involved in CC-induced endothelial dysfunction, which inhibits decreases in nitric oxide (NO) level and endothelial nitric oxide synthase (eNOS) activity and increases in inflammatory factors and adhesion molecules. Besides, SIRT1 and SIRT6 regulated the protein expression of ACE2 in CC-stimulated human umbilical vein endothelial cells (HUVECs). Moreover, bioinformatics analysis from the Enrichr database indicated that activating transcription factor 2 (ATF2), is highly correlated with genes that significantly upregulated after infection with the SIRT6 adenovirus vector. In CC-induced HUVECs, ACE2 expression was up-regulated in cells transfected with ATF2 siRNA. However, further mechanism studies revealed that overexpression of SIRT6 decreases the accumulation of p-ATF2 in the nucleus, but did not affect p-ATF2 expression in the cytoplasm. Taken together, these data indicated that SIRT6 regulates ACE2 might via inhibiting the accumulation of nucleus p-ATF2 in CC-induced endothelial dysfunction.
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http://dx.doi.org/10.1016/j.yexcr.2021.112526DOI Listing
May 2021

Metformin attenuates post-epidural fibrosis by inhibiting the TGF-β1/Smad3 and HMGB1/TLR4 signaling pathways.

J Cell Mol Med 2021 Apr 21;25(7):3272-3283. Epub 2021 Feb 21.

NHC Key Laboratory of Antibody Technique, Department of Immunology, Nanjing Medical University, Nanjing, China.

Excessive post-epidural fibrosis is a common cause of recurrent back pain after spinal surgery. Though various treatment methods have been conducted, the safe and effective drug for alleviating post-epidural fibrosis remains largely unknown. Metformin, a medicine used in the treatment of type 2 diabetes, has been noted to relieve fibrosis in various organs. In the present study, we aimed to explore the roles and mechanisms of metformin in scar formation in a mouse model of laminectomy. Post-epidural fibrosis developed in a mouse model of laminectomy by spinous process and the T12-L2 vertebral plate with a rongeur. With the administration of metformin, post-epidural fibrosis was reduced, accompanied with decreased collagen and fibronectin in the scar tissues. Mechanistically, metformin decreased fibronectin and collagen deposition in fibroblast cells, and this effect was dependent on the HMGB1/TLR4 and TGF-β1/Smad3 signalling pathways. In addition, metformin influenced the metabolomics of the fibroblast cells. Taken together, our study suggests that metformin may be a potential option to mitigate epidural fibrosis after laminectomy.
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http://dx.doi.org/10.1111/jcmm.16398DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8034438PMC
April 2021

A Magnetically Guided Self-Rolled Microrobot for Targeted Drug Delivery, Real-Time X-Ray Imaging, and Microrobot Retrieval.

Adv Healthc Mater 2021 03 27;10(6):e2001681. Epub 2021 Jan 27.

Korea Institute of Medical Microrobotics, 43-26, Cheomdangwagi-ro 208-beon-gil, Buk-gu, Gwangju, 61011, South Korea.

Targeted drug delivery using a microrobot is a promising technique capable of overcoming the limitations of conventional chemotherapy that relies on body circulation. However, most studies of microrobots used for drug delivery have only demonstrated simple mobility rather than precise targeting methods and prove the possibility of biodegradation of implanted microrobots after drug delivery. In this study, magnetically guided self-rolled microrobot that enables autonomous navigation-based targeted drug delivery, real-time X-ray imaging, and microrobot retrieval is proposed. The microrobot, composed of a self-rolled body that is printed using focused light and a surface with magnetic nanoparticles attached, demonstrates the loading of doxorubicin and an X-ray contrast agent for cancer therapy and X-ray imaging. The microrobot is precisely mobilized to the lesion site through automated targeting using magnetic field control of an electromagnetic actuation system under real-time X-ray imaging. The photothermal effect using near-infrared light reveals rapid drug release of the microrobot located at the lesion site. After drug delivery, the microrobot is recovered without potential toxicity by implantation or degradation using a magnetic-field-switchable coiled catheter. This microrobotic approach using automated control method of the therapeutic agents-loaded microrobot has potential use in precise localized drug delivery systems.
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http://dx.doi.org/10.1002/adhm.202001681DOI Listing
March 2021

On the basic reproduction number in semi-Markov switching networks.

J Biol Dyn 2021 12;15(1):73-85

Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, Alberta, Canada.

Basic reproduction number in network epidemic dynamics is studied in the case of stochastic regime-switching networks. For generality, the dependence between successive networks is considered to follow a continuous time semi-Markov chain. is the weighted average of the basic reproduction numbers of deterministic subnetworks. Its position with respect to 1 can determine epidemic persistence or extinction in theories and simulations.
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http://dx.doi.org/10.1080/17513758.2020.1867246DOI Listing
December 2021

Tumor Targeted Multifunctional Magnetic Nanobubbles for MR/US Dual Imaging and Focused Ultrasound Triggered Drug Delivery.

Front Bioeng Biotechnol 2020 7;8:586874. Epub 2020 Dec 7.

School of Medical Imaging, Xuzhou Medical University, Xuzhou, China.

The development of multifunctional nanoplatforms that are safe and have multiple therapeutic functions integrated with dual- or multi-imaging modality is one of the most urgent medical requirements for active cancer therapy. In our study, we prepared multifunctional magnetic nanobubbles (MF-MNBs) by co-encapsulating superparamagnetic iron oxide nanoparticles (SPIONs) and doxorubicin into polylactideco-glycolide-polyethylene glycol-folate (PLGA-PEG-FA) polymer-based nanobubbles for tumor-targeted ultrasound (US)/magnetic resonance (MR) imaging and focused ultrasound (FUS)-triggered drug delivery. Hydrophobic SPIONs were successfully embedded into MF-MNBs by a typical double emulsion process. The MF-MNBs were highly dispersed with well-defined spherical morphology and an average diameter of 208.4 ± 12.58 nm. The potential of MF-MNB as a dual-modal contrast agent for US and MR imaging was investigated via study, and the MF-MNB exhibits promising US/MR contrast ability. Moreover, tumor targeting ability was further enhanced by folate conjugation and assessed through cell test. Furthermore, FUS, as a non-invasive and remote-control technique, was adopted to trigger the release of doxorubicin from MF-MNB and generate the sonoporation effect to enhance drug release and cellular uptake of MF-MNBs. The 4T1 cell viability was significantly decreased by FA ligand-receptor-mediated targeting and FUS sonication. In addition, the developed MF-MNB also exhibits enhanced accumulation in tumor site by FA ligand-receptor-mediated tumor targeting, in which the accumulation of MF-MNB was further enhanced by FUS sonication. Hence, we believe that the MF-MNB could be a promising drug nanocarrier for US/MR-guided anticancer drug delivery to improve cancer treatment efficacy.
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http://dx.doi.org/10.3389/fbioe.2020.586874DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750502PMC
December 2020

The risk factor assessment of the spread of foot-and-mouth disease in mainland China.

J Theor Biol 2021 03 18;512:110558. Epub 2020 Dec 18.

Complex Systems Research Center, Shanxi University, Taiyuan, Shanxi 030006, PR China; Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Taiyuan, Shanxi 030006, PR China. Electronic address:

In China, foot-and-mouth disease (FMD) serotype O remains prevalent, and its main host is pigs. Infected but undiscovered pigs can carry foot-and-mouth disease virus (FMDV) for a longtime. And, the virus can spread among farms through pig trade. Although individual vaccination at least 2 times a year and monthly monitoring disease and culling all individual in same group for pigs are adopted vigorously in China, the epidemic remains prevalent. Therefore, in this paper, based on these propagation characteristics and control measures of the epidemic in China, we take the pig farms as research individuals, the trade among farms as transmission routes to establish a dynamic model with nonlinear incidence. In addition, we use this model to assess the impact of trade and transport of pigs among farms on the spread of foot-and-mouth disease virus (FMDV), and to assess the effect of the immunization, monitoring and culling adopted presently in China on the control of the epidemic. By the dynamical analysis of the model, it is found that there will appear backward branching under some conditions, which means that there are two spreading thresholds for the disease, and the disease development trend is also related to the current epidemic situation. Besides, we give the threshold conditions of key parameters to control the spread of FMD. By carrying out data fitting and parameter estimation, we confirm the model rationality, and give four evaluation indexes: the basic reproduction number R of FMD serotype O in China, the value of the infected farms at the equilibria, annual probability of a susceptible farm being infected and annual transmission intensity of an infected farm. By carrying out the sensitivity analysis of key parameters on four evaluation indexes, the effect of parameters on the spread of the disease can be intuitively observed. All these can provide a theoretical basis for understanding of the trading-based transmission mechanism, control and prevention of foot-and-mouth disease in pigs in China.
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http://dx.doi.org/10.1016/j.jtbi.2020.110558DOI Listing
March 2021

A Progressive Somatic Cell Niche Regulates Germline Cyst Differentiation in the Drosophila Ovary.

Curr Biol 2021 Feb 18;31(4):840-852.e5. Epub 2020 Dec 18.

National Institute of Biological Sciences, No. 7 Science Park Road, Zhongguancun Life Science Park, Beijing 102206, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 102206, China. Electronic address:

In the germarium of the Drosophila ovary, developing germline cysts are surrounded by a population of somatic escort cells that are known to function as the niche cells for germline differentiation; however, the underlying molecular mechanisms of this niche function remain poorly understood. Through single-cell gene expression profiling combined with genetic analyses, we here demonstrate that the escort cells can be spatially and functionally divided into two successive domains. The anterior escort cells (aECs) specifically produce ecdysone, which acts on the cystoblast to promote synchronous cell division, whereas the posterior escort cells (pECs) respond to ecdysone signaling and regulate soma-germline cell adhesion to promote the transition from 16-cell cyst-to-egg chamber formation. The patterning of the aEC and pEC domains is independent of the germline but is dependent on JAK/STAT signaling activity, which emanates from the posterior. Thus, a heterogeneous population of escort cells constitutes a stepwise niche environment to orchestrate cystoblast division and differentiation toward egg chamber formation.
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http://dx.doi.org/10.1016/j.cub.2020.11.053DOI Listing
February 2021

Transmission dynamics of brucellosis: Mathematical modelling and applications in China.

Comput Struct Biotechnol J 2020 21;18:3843-3860. Epub 2020 Nov 21.

Complex Systems Research Center, Shanxi University, Taiyuan, Shanxi 030006, China.

Brucellosis, the most common zoonotic disease worldwide, represents a great threat to animal husbandry with the potential to cause enormous economic losses. Meanwhile, brucellosis is one of the major public-health problems in China, and the number of human brucellosis cases has increased dramatically in recent years. In order to show the main features of brucellosis transmission in China, we give a systematic review on the transmission dynamics of brucellosis including a series of mathematical models and their applications in China. For different situations, dynamical models of brucellosis transmission in single population and multiple populations are devised based on ordinary differential equations. Furthermore, we revealed the spatial-temporal characteristics and effective control measures of brucellosis transmission. The results may provide new perspectives for the prevention and control of other types of zoonoses.
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http://dx.doi.org/10.1016/j.csbj.2020.11.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7720096PMC
November 2020

Rapid detection of the New Delhi metallo-β-lactamase (NDM) gene by recombinase polymerase amplification.

Infect Genet Evol 2021 01 13;87:104678. Epub 2020 Dec 13.

Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China. Electronic address:

New Delhi metallo-β-lactamase (NDM) is a series of enzyme conferring resistance to β-lactam antibiotics including the carbapenems. The bla gene has been reported in a variety of Gram-negative bacilli, especially in the Enterobacteriaceae and Acinetobacter spp., which is deeply disconcerting for public health worldwide. In this study, recombinase polymerase amplification assays using a basic detection (Basic-RPA) and a real-time fluorescent detection (Exo-RPA) were established for detecting bla gene. The RPA reactions were performed at 39 °C and finished within 20 min. Using different copy numbers of pMD18T-NDM plasmid DNA as templates, we identified the detection limit of Basic-RPA assay (1.85 × 10 copies/μL), conventional PCR assay (1.85 × 10 copies/μL), Exo-RPA assay (1.85 × 10 copies/μL) and real-time PCR assay (1.85 × 10 copies/μL). Both Basic-RPA and Exo-RPA assays were highly specific for detecting bla, as there were no cross-reactions with the strains without bla gene. Examination of 62 clinical samples by RPA assays and PCR assays showed the same results, suggesting that RPA assays are reliable in clinical diagnosis. The amplification time of RPA is much shorter than that of other molecular techniques, it is easy to implement and has the potential for clinical application.
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http://dx.doi.org/10.1016/j.meegid.2020.104678DOI Listing
January 2021

Neutrophil extracellular traps promote scar formation in post-epidural fibrosis.

NPJ Regen Med 2020 Oct 30;5(1):19. Epub 2020 Oct 30.

NHC Key Laboratory of Antibody Technique, Department of Immunology, Nanjing Medical University, Nanjing, 211166, China.

Low back pain following spine surgery is a major complication due to excessive epidural fibrosis, which compresses the lumbar nerve. The mechanisms of epidural fibrosis remain largely elusive. In the drainage samples from patients after spine operation, neutrophil extracellular traps (NETs) and NETs inducer high-mobility group box 1 were significantly increased. In a mouse model of laminectomy, NETs developed in the wound area post epidural operation, accompanied with macrophage infiltration. In vitro, macrophages ingested NETs and thereby increased the elastase from NETs via the receptor for advanced glycation end product. Moreover, NETs boosted the expression of fibronectin in macrophages, which was dependent on elastase and could be partially blocked by DNase. NF-κB p65 and Smad pathways contributed to the increased expression fibronectin in NETs-treated macrophages. In the mouse spine operation model, post-epidural fibrosis was significantly mitigated with the administration of DNase I, which degraded DNA and cleaved NETs. Our study shed light on the roles and mechanisms of NETs in the scar formation post spine operation.
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http://dx.doi.org/10.1038/s41536-020-00103-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599244PMC
October 2020

Fangcang shelter hospitals during the COVID-19 epidemic, Wuhan, China.

Bull World Health Organ 2020 Dec 29;98(12):830-841D. Epub 2020 Sep 29.

Centre for Disease Modelling, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada.

Objective: To design models of the spread of coronavirus disease-2019 (COVID-19) in Wuhan and the effect of Fangcang shelter hospitals (rapidly-built temporary hospitals) on the control of the epidemic.

Methods: We used data on daily reported confirmed cases of COVID-19, recovered cases and deaths from the official website of the Wuhan Municipal Health Commission to build compartmental models for three phases of the COVID-19 epidemic. We incorporated the hospital-bed capacity of both designated and Fangcang shelter hospitals. We used the models to assess the success of the strategy adopted in Wuhan to control the COVID-19 epidemic.

Findings: Based on the 13 348 Fangcang shelter hospitals beds used in practice, our models show that if the Fangcang shelter hospitals had been opened on 6 February (a day after their actual opening), the total number of COVID-19 cases would have reached 7 413 798 (instead of 50 844) with 1 396 017 deaths (instead of 5003), and the epidemic would have lasted for 179 days (instead of 71).

Conclusion: While the designated hospitals saved lives of patients with severe COVID-19, it was the increased hospital-bed capacity of the large number of Fangcang shelter hospitals that helped slow and eventually stop the COVID-19 epidemic in Wuhan. Given the current global pandemic of COVID-19, our study suggests that increasing hospital-bed capacity, especially through temporary hospitals such as Fangcang shelter hospitals, to isolate groups of people with mild symptoms within an affected region could help curb and eventually stop COVID-19 outbreaks in communities where effective household isolation is not possible.
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http://dx.doi.org/10.2471/BLT.20.258152DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7716094PMC
December 2020