Differential expression of virulence factors in clinical isolates of Candida parapsilosis / 中国感染控制杂志

Objective To compare the differences in virulence-related factor aspartate protease,biofilm formation,and gene expression among clinical isolates of Candida parapsilosis(C.parapsilosis).Methods Gene sequencing and microsatellite typing(MT)method were adopted to identify C.parapsilosis isolated from patients with clinical fungal infection.The production of secreted aspartate protease and biofilm formation ability of each strain were de-tected,and the expression of biofilm formation related-genes BCR1,EFG1,and HWP1,as well as aspartate prote-ase virulence genes SAPP1,SAPP2,SAPP3 were compared among the strains.Results A total of 8 clinically iso-lated C.parapsilosis strains were collected,all of which were identified as genotype Ⅰ.Based on microsatellite ty-ping results,8 clinical strains were divided into 4 microsatellite types.G1,G2,and G3 strains isolated from the urine,peripherally inserted central catheters(PICC),and blood of patient A were of different subtypes.J1,J2,J3,J4,and J5 strains were of the same type,and isolated from blood specimens of patient B at different periods.All 8 clinical strains could form biofilm,and their biofilm formation ability was higher than that of the standard strain of C.parapsilosis(ATCC 22019).G1,G3 and J5 strains had strong biofilm formation ability,J1,J2,J3,and J4 strains had moderate biofilm formation ability,and G2 strain had weak biofilm formation ability.All of the eight clinical isolates secreted aspartate protease,and their in vitro expression levels of the enzyme were higher than that of the standard strain(ATCC 22019).G3,G1,and G2 strains showed low,moderate,and high in vitro enzyme expression respectively,with statistical differences(all P＜0.05).Enzyme expressed moderately in J1 and J5 strains,and highly in J2,J3,and J4 strains.Difference between moderate and high expressions was statistically significant(P＜0.05).The expression levels of biofilm formation genes BCR1,EFG1,and HWP1 in various strains isolated from patients A and B increased.In strains isolated from patient A,the expression level of EFG1 gene in G1 strain was higher than that in G2 strain(P＜0.05).There was no statistically significant difference in BCR1,EFG1,and HWP1 gene expression levels among strains isolated from patient B.The expression levels of as-partate protein genes(SAPP1,SAPP2,and SAPP3)in various strains isolated from patients A and B increased.The expression levels of SAPP1 and SAPP2 in strain G1 were higher than those in G2 and G3(both P＜0.05).There was no statistically significant difference in the expression levels of SAPP1,SAPP2,and SAPP3 genes in strains from patient B.Conclusion Clinical isolates of C.parapsilosis have higher biofilm formation and aspartate protease production abilities than standard strain.The expression of virulence factors varies among strains isolated from different specimens,while there is no significant difference in the expression of virulence factors among strains isolated at different periods.Patients may have been infected with different MT types of C.parapsilosis in multiple sites during the same period.

Research progress on SENP1/HIF-1α regulation of vascular differentiation of dental pulp stem cells / 中国医师杂志

Dental pulp stem cells (DPSC) are pluripotent stem cells with high differentiation potential isolated from dental pulp. Using DPSC for vascular regeneration may be a good option. Hypoxia inducible factor-1α (HIF-1α) is an upstream gene of vascular endothelial growth factor (VEGF), and the small ubiquitin like protease 1 (SENP1) can reverse the small ubiquitin like (SUMO) modification of HIF-1α. Through the regulation of SENP1/HIF-1α, good vascular regeneration characteristics have been demonstrated in many in vitro and in vivo experiments. The SENP1/HIF-1α signaling axis has varying degrees of promoting and inhibiting effects on many solid tumors. Although there is relatively little literature on the role of the SENP1/HIF-1α signaling axis in dental pulp stem cells, it can be determined that SENP1/HIF-1α plays an important role in the angiogenesis of dental pulp stem cells. This article will elucidate the SENP1/HIF-1α signaling pathway and its mechanism of promoting vascular differentiation of DPSC.

Production, purification and characterization of novel protease from Bacillus amyloliquefaciens D19 isolated in Vietnam

Aims@#Microorganisms play a vital role in the breakdown of natural organic compounds and are valuable objects for worldwide enzyme production. The aim of this study was to identify favorable production conditions for Bacillus amyloliquefaciens D19 protease, followed by the purification and chemical characterization of this novel enzyme to assess its potential applications in various fields.@*Methodology and results@#In this study, favorable conditions of protease production from B. amyloliquefaciens D19 were determined using a medium containing soluble starch (1.5%), earthworm extract (1.0%), yeast extract (0.5%), NaCl (1.0%), at pH 7.0-8.0, 37 °C for 36 h with 150 rpm shaking condition. The protease was purified and had a molecular weight of about 23 kDa. The optimum condition for casein hydrolysis was at 40 °C and pH 6.5-7.0 in the presence of 1.0 mM Na+ or 5.0 mM Zn2+. The enzymatic activity was maintained at 75-100% at 30-50 °C and in pH 6.0-10.0. The values of Vmax and KM were also determined as 1547 U/mg and 6.33 mg/mL, respectively.@*Conclusion, significance and impact of study@#The identified optimal conditions will serve as the foundation for the production of the 23 kDa B. amyloliquefaciens D19 protease, one of the smallest proteases within the Bacillus genus. Moreover, its notable heat resistance, broad pH tolerance, high substrate catalysis and moderate substrate binding affinity make this enzyme a promising candidate for various applications in the food-feed and brewing industries.

Research progress on ocular diseases associated with SARS-CoV-2 / 国际眼科杂志(Guoji Yanke Zazhi)

The corona virus disease 2019(COVID-19)in 2019 has shown a global pandemic status in a short time since its outbreak, and many variants of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)were highly infectious and pathogenic. SARS-CoV-2 may infect tissue cells through the mediation of angiotensin-converting enzyme-2(ACE2)and transmembrane serine protease 2(TMPRSS2), leading to different diseases. Clinically, respiratory, cardiovascular, and gastrointestinal systems diseases are relatively common; many patients also seek medical attention based on eye symptoms as their main complaint. Compared with severe systemic diseases, eye-related symptoms are easily overlooked. This article reviews the pathogenesis and cases of various eye diseases related to SARS-CoV-2, aiming to enhance clinicians' attention to SARS-CoV-2-related eye diseases, avoid delaying the disease and causing irreversible loss of vision, and provide new ideas for the prevention and treatment of eye diseases.

Network pharmacology and molecular docking to study the mechanism of action of alpinumisoflavone in a temporomandibular joint osteoarthritis cell model / 口腔疾病防治

Objective@#To explore the potential role of alpinumisoflavone (AIF) in the treatment of temporomandibular joint osteoarthritis (TMJOA) cell model through network pharmacology and molecular docking and to provide a research basis for AIF in the treatment of TMJOA.@*Methods@#GeneCards, OMIM, DisGeNET, and PharmGKB databases were used to screen TMJOA disease targets, and PharmMapper and HERB were used to retrieve AIF-related targets. The intersection targets of the compounds and diseases were uploaded to the STRING database to obtain the key targets for GO and KEGG enrichment analysis, while the key targets in related signaling pathways were evaluated through molecular docking. Approval was obtained from the Ethics Committee to extract condylar chondrocytes from 3-week-old SD rats. The CCK-8 assay was used to detect AIF cytotoxicity on condylar chondrocytes. Condylar chondrocytes were induced with 10 ng/mL interleukin 1β (IL-1β) for 24 h to construct a TMJOA cell model. The experiment was divided into three groups: control group, comprising condylar chondrocytes cultured in DMEM for 48 h; IL-1β group, comprising condylar chondrocytes pre-cultured in DMEM for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h; and the IL-1β+10 μmol/L AIF group, comprising condylar chondrocytes pre-cultured in DMEM medium containing 10 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The effect of AIF on condylar chondrocyte apoptosis in the TMJOA cell model was detected by flow cytometry. The experiment was divided into four groups: control group, IL-1β group, IL-1β+10 μmol/L AIF group, and IL-1β+30 μmol/L AIF group. The IL-1β+30 μmol/L AIF group was pre-cultured in DMEM containing 30 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The remaining three groups were cultured in the same manner as before. The mRNA and protein expression of apoptosis-associated B-cell leukemia/lymphoma-2 (Bcl2), cysteinyl aspartate specific protease 3 (caspase-3), matrix degradation-associated a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4), matrix metalloproteinase 3 (MMP3), and matrix metalloproteinase 13 (MMP13) were detected by qPCR and western blot, by AIF in the TMJOA cell model.@*Results@#The PharmMapper and HERB database search yielded 300 AIF compound targets. The GeneCards, OMIM, DisGeNET, and PharmGKB databases yielded 378 TMJOA disease targets. Thirty-three potential common targets were obtained by intersecting compounds with disease targets. The common targets were uploaded into the STRING database to obtain 31 key targets that were mainly associated with apoptosis and extracellular matrix degradation. This process may be associated with the MAPK, estrogen, and TNF signaling pathways. The molecular docking results showed that AIF has good binding activity with extracellular signal-regulated kinase 1/2 (ERK1/2) and estrogen receptor gene 1/2 (ESR1/2), which are key targets in the MAPK and estrogen signaling pathways. The CCK-8 assay showed that AIF had no obvious cytotoxicity to condylar chondrocytes. The cell experiments showed that AIF inhibited apoptosis in the IL-1β+10 μmol/L AIF group compared to the IL-1β group. Compared to the IL-1β group in the IL-1β+10 μmol/L AIF group and the IL-1β+30 μmol/L AIF group, AIF upregulated Bcl2 and downregulated caspase-3 mRNA and protein expression and inhibited ADAMTS4, MMP3, and MMP13 mRNA and protein expression.@*Conclusion@#AIF inhibited apoptosis in the TMJOA cell model by upregulating Bcl2 and downregulating caspase-3 mRNA and protein expression, and inhibited extracellular matrix degradation induced by IL-1β, thereby delaying TMJOA progression.

Effect of Modified Shenhong Tongluo Prescription on Cell Apoptosis in Rats with Myocardial Ischemia-reperfusion Injury by Bcl-2/Bax/Caspase-3 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of modified Shenhong Tongluo prescription on cell apoptosis in rats with myocardial ischemia-reperfusion injury （MIRI）. MethodSixty Sprague-Dawley （SD） rats were randomly divided into a blank group， a model group， low-， medium-， and high-dose groups of modified Shenhong Tongluo prescription， and a simvastatin group. Except for the blank group， a rat model of MIRI was prepared by ligating the left anterior descending coronary artery. Starting from the first day after successful modeling， the blank group （1.0 mL·kg-1 physiological saline）， model group （1.0 mL·kg-1 physiological saline）， low-， medium-， and high-dose groups of modified Shenhong Tongluo prescription （1.031， 2.063， and 4.126 g·kg-1 Shenhong Tongluo prescriptiona standard concentrate）， and simvastatin group （0.71 mg·kg-1 simvastatin） were orally administered once daily for 2 weeks. Hematoxylin-eosin （HE） staining was used to observe the pathological changes of cardiomyocytes. Enzyme-linked immunosorbent assay （ELISA） was used to detect the levels of serum creatine kinase isoenzyme （CK-MB）， interleukin-6 （IL-6）， and tumor necrosis factor-α （TNF-α）. TdT-mediated dUTP nick-end labeling（TUNEL） staining was used to detect the apoptosis rate of rat cardiomyocytes. Western blot was used to detect the expression levels of apoptosis-related proteins B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and caspase-3. ResultCompared with the blank group， in the model group， HE staining showed disturbed arrangement of cardiomyocytes， incomplete fibers， focal necrosis of cardiomyocytes， and inflammatory cell infiltration； serum CK-MB， IL-6， and TNF-α levels were significantly increased （P<0.05）； apoptosis rate of cardiomyocytes was significantly increased （P<0.01）， with significantly increased expression levels of Bax and Caspase-3 proteins， and significantly decreased Bcl-2 expression （P<0.05）. Compared with the model group， the low-， medium-， and high-dose groups of modified Shenhong Tongluo prescription significantly reduced CK-MB， IL-6， and TNF-α levels （P<0.05）， significantly downregulated cardiomyocyte apoptosis rate （P<0.05）， significantly decreased Bax and Caspase-3 proteins， and significantly increased Bcl-2 expression levels （P<0.01）. In the modified Shenhong Tongluo prescription groups， the expression levels of Bax and Caspase-3 proteins significantly decreased with increasing dosage， while the expression level of Bcl-2 significantly increased with increasing dosage of modified Shenhong Tongluo prescription （P<0.05）. ConclusionShenhong Tongluo prescription can alleviate myocardial tissue pathological damage and reduce myocardial cell apoptosis， possibly by inhibiting Caspase-3 and Bax expression and promoting Bcl-2 expression.

Function and research progress of ubiquitin-specific protease 7 in colorectal cancer / 临床外科杂志

Ubiquitin-specific protease 7(USP7)is a deubiquitinating enzyme involved in a wide range of cellular processes,playing a key role in the regulation of cell proliferation and apoptosis,cell division,differentiation,DNA damage repair,epigenetic regulation and other biological processes.This article briefly summarizes the structure and extensive biological functions of USP7,and also describes the research progress of USP7 in colorectal cancer in recent years and potential directions for future research.

Expression of Serum Vaspin and SFRP5 in Children with Idiopathic Nanosomia and Their Diagnostic Value / 现代检验医学杂志

Objective To explore the expression level of visceral adipose tissue-derived serine protease inhibitor(Vaspin)and secreted frizzled-related protein5(SFRP5)in the serum of children with idiopathic short stature(ISS)and its diagnostic value.Methods 70 children with ISS diagnosed in the First Hospital of Zhangjiakou from December 2021 to February 2023 were selected as the disease group,while 72 healthy volunteer children who underwent physical examination were collected as the control group.Immunoluminescence was applied to detect the expression level of VASPIN,Enzyme-linked immunosorbent assay(ELISA)was applied to detect the expression level of SFRP5 the clinical data of children in two groups were analyzed.Receiver operating characteristic(ROC)curve was applied to analyze the diagnostic value of serum Vaspin and SFRP5 for ISS,multivariate Logistic regression was used to analyze the influencing factors of ISS.Results Compared with the control group,the serum Vaspin level in the disease group was obviously increased(2.89±0.92 ng/ml vs 1.81±0.42 ng/ml),while the SFRP5 level was obviously reduced(10.22±2.84 pg/ml vs 13.21±3.53 pg/ml),the differences were statistically significant(t=9.040,5.552,all P＜0.05).The weight,height,body mass index(BMI)and proportion of sexual development stage II～V of children in the disease group were obviously lower than those in the control group,and the differences were statistically significant(t=7.687,6.330,5.559,7.024,all P＜0.05).The area under ROC curve showed that the AUC of Vaspin and SFRP5 and their combined detection in the diagnosis of ISS were 0.768,0.849 and 0.925,respectively,the combined diagnosis efficacy of Vaspin and SFRP5 was better than that of serum Vaspin and SFRP5 alone(Z =3.829,P＜0.001;Z =2.141,P=0.032).Multivariate Logistic regression analysis showed that BMI(OR=0.508,95%CI:0.260～0.991),Vaspin(OR=3.458,95%CI:1.125～10.631)and SFRP5(OR=0.378,95%CI:0.153～0.935)were the influencing factors for ISS(all P＜0.05).Conclusion The expression level of Vaspin in the serum of children with ISS is obviously increased,while the expression level of SFRP5 is obviously reduced.The two are influencing factors of ISS,and the combined detection of their expression levels has certain value in the diagnosis of ISS.

Hei Xiaoyaosan Regulates Fas/FasL/Caspase-8/Caspase-3 Signaling Pathway to Inhibit Neuronal Apoptosis in AD Rats / 中国实验方剂学杂志

ObjectiveTo explore the effect and mechanism of Hei Xiaoyaosan in regulating the tumor necrosis factor receptor superfamily member 6 （Fas）/Fas ligand （FasL）/cysteine protease-8 （Caspase-8）/cysteine protease-3 （Caspase-3） signaling pathway to intervene in neuronal apoptosis and prevent Alzheimer's disease （AD）. MethodNinety SPF-grade SD male rats of 4 months old were selected and randomly grouped as follows： 10 rats in the blank group， 10 rats in the sham group （bilateral hippocampus injected with 1 μL normal saline）， and 70 rats in the modeling group ［bilater hippocampus injected with 1 μL amyloid-beta protein 1-42 （Aβ1-42） solution for the modeling of AD］. Fifty successfully modeled rats were selected and randomly assigned into model， donepezil hydrochloride （0.45 mg·kg-1）， and high-， medium-， and low-dose （15.30， 7.65， 3.82 g·kg-1） Hei Xiaoyaosan groups. Rats were administrated with corresponding agents by gavage once a day for 42 days. Terminal-deoxynucleoitidyl transferase-mediated nick end labeling （TUNEL） was employed to observe the apoptosis of neurons in the cortex and hippocampus， and immunohistochemistry （IHC） was used to detect the expression of B-cell lymphoma-2 （Bcl-2） and Bcl-2-associated X protein （Bax） in the hippocampus. Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） was employed to determine the mRNA levels of Fas， FasL， and Fas-associated protein with death domain （Fadd）. Western blot was used to determine the protein levels of Fas， FasL， Fadd， Caspase-3， cleved Caspase-3， Caspase-8， and cleved Caspase-8. ResultCompared with the blank group and sham group， the model group showed increased apoptosis rate in the cortex and hippocampus （P<0.01）， elevated Bax level （P<0.01）， lowered Bcl-2 level （P<0.01）， up-regulated mRNA levels of Fas， FasL， and Fadd in the hippocampus （P<0.01）， and up-regulated protein levels of Fas， FasL， Fadd， cleaved Caspase-3， and cleaved Caspase-8 （P<0.01）. Compared with the model group， donepezil hydrochloride and Hei Xiaoyaosan at high and medium doses decreased the apoptosis rate in the cortex and hippocampus （P<0.05， P<0.01）， lowered the Bax level （P<0.01）， elevated the Bcl-2 level （P<0.01）， and down-regulated the mRNA levels of Fas， FasL， and Fadd and the protein levels of Fas， FasL， Fadd， cleaved Caspase-3， and cleaved Caspase-8 （P<0.05， P<0.01） in the hippocampus. Low-dose Hei Xiaoyaosan decreased the apoptosis rate in the cortex and hippocampus （P<0.05， P<0.01）， lowered the Bcl-2 level （P<0.01）， and down-regulated the mRNA levels of FasL and Fadd （P<0.05） and the protein levels of Fas， FasL， Fadd， cleaved Caspase-3， and cleaved Caspase-8 （P<0.05） in the hippocampus. ConclusionHei Xiaoyaosan can protect neurons in the cortex and hippocampus of AD rats by inhibiting the apoptosis mediated by the Fas/FasL/Caspase-8/Caspase-3 signaling pathway.

Genetic diversity in the partial sequence of the HIV-1 gag gene among people living with multidrug-resistant HIV-1 infection

ABSTRACT The group-specific antigen (gag) plays a crucial role in the assembly, release, and maturation of HIV. This study aimed to analyze the partial sequence of the HIV gag gene to classify HIV subtypes, identify recombination sites, and detect protease inhibitor (PI) resistance-associated mutations (RAMs). The cohort included 100 people living with HIV (PLH) who had experienced antiretroviral treatment failure with reverse transcriptase/protease inhibitors. Proviral HIV-DNA was successfully sequenced in 96 out of 100 samples for gag regions, specifically matrix (p17) and capsid (p24). Moreover, from these 96 sequences, 82 (85.42%) were classified as subtype B, six (6.25%) as subtype F1, one (1.04%) as subtype C, and seven (7.29%) exhibited a mosaic pattern between subtypes B and F1 (B/F1), with breakpoints at p24 protein. Insertions and deletions of amino acid at p17 were observed in 51 samples (53.13%). The prevalence of PI RAM in the partial gag gene was observed in 78 out of 96 PLH (81.25%). Among these cases, the most common mutations were R76K (53.13%), Y79F (31.25%), and H219Q (14.58%) at non-cleavage sites, as well as V128I (10.42%) and Y132F (11.46%) at cleavage sites. While B/F1 recombination was identified in the p24, the p17 coding region showed higher diversity, where insertions, deletions, and PI RAM, were observed at high prevalence. In PLH with virological failure, the analysis of the partial gag gene could contribute to more accurate predictions in genotypic resistance to PIs. This can aid guide more effective HIV treatment strategies.

Estudio computacional de las interacciones moleculares entre el timol y los residuos HIS41 y CYS145 presentes en el sitio activo de la proteasa 3CLpro

La proteína proteasa 3CLpro del SARS-CoV-2 es una enzima crucial para la replicación viral, razón por la cual se convierte en un blanco terapéutico de gran importancia. El timol (2-isopropil-5-me-tilfenol), un compuesto natural que se encuentra en el tomillo (Thymus vulgaris), exhibe potencial actividad antiviral contra la proteasa 3CLpro. En este estudio, usando acoplamiento molecular con AutoDockTools-1.5.6, se evaluaron las energías de interacción molecular entre el timol y los residuos de aminoácidos en el sitio activo de la proteína proteasa 3CLpro. Luego, con la teoría cuántica de Átomos en Moléculas (QTAIM) y la de Interacciones no covalentes (NCI) se analizaron los tipos de interacciones moleculares entre los residuos de aminoácidos identificados y el timol. Los cálculos cuánticos se llevaron con el software Orca-5.0.3, utilizando el método DFT con el funcional M06-2X y el conjunto base aug-cc-pVDZ en fase gaseosa. Los resultados de acoplamiento molecular indican que el timol se une a la proteína 3CL con una energía de interacción igual a -3,784 kcal/mol. El análisis QTAIM indica la presencia de puntos críticos de enlace entre el timol y los residuos HIS41 y CYS145. Además, se observa la formación de un enlace de hidrógeno entre el grupo OH del timol y el residuo CYS145, lo cual es corroborado por los análisis ELF (Electron Localization Function) y NCI (Non Covalent Interactions). Finalmente, el método NCI confirma la presencia de interacciones de Van der Waals con el residuo HIS41. Los resultados sugieren que el mecanismo de inhibición de la actividad de la proteína 3CLpro es controlado por interacciones moleculares tipo puente de hidrógeno e interacciones débiles.

The protease 3CLpro of the SARS-CoV-2 is a crucial enzyme for viral replication, becoming a highly important therapeutic target. Thymol (2-isopropyl-5-methyl-phenol), a naturally occurring compound found in thyme, exhibits potential antiviral activity against the 3CLpro protease. In this study, using molecular docking with AutoDockTools-1.5.6, the molecular interaction energies between thymol and amino acid residues in the active site of the protein protease 3CLpro were evaluated. Then, with the Atoms in Molecules (QTAIM) and Non-covalent Interactions (NCI) theories, the types of molecular interactions between identified amino acid residues and thymol were analyzed. Quantum calculations were carried out with the Orca-5.0.3 software using the DFT method with the M06-2X functional and the aug-cc-pVDZ basis set in the gas phase. The molecular docking results indicate that thymol is linked to the 3CL protein with an interaction energy equal to -3.784 kcal/mol. QTAIM analysis indicates the presence of critical binding sites between thymol and residues HIS41 and CYS145. In addition, the formation of a hydrogen bond between the OH group of thymol and the CYS145 residue is observed, which is corroborated by the ELF and NCI analyses. Finally, the NCI method confirms the presence of Van der Waals interactions with the HIS41 residue. The results suggest that the mechanism of inhibition of the activity of the 3CLpro protein is controlled by molecular interactions such as hydrogen bonding and weak interactions.

A protease 3CLpro do SARS-CoV-2 é uma enzima crucial para a replicação viral, tornando-se um alvo terapêutico de grande importÅncia. O timol (2-isopropil-5-me-tilfenol), um composto natural encontrado no tomilho, exibe potencial atividade antiviral contra a protease 3CLpro. Neste estudo, utilizando o docking molecular com o AutoDockTools-1.5.6, foram avaliadas as energias de interação molecular entre o timol e os residuos de aminoácidos no sítio ativo da proteína protease 3CLpro. Em seguida, com a teoria quantica de atomos em moleculas (QTAIM) e da interacões no-covalentes (NCI), foram analisados os tipos de interações moleculares entre os resíduos de aminoácidos identificados e o timol. Os cálculos quÅnticos foram realizados com o software Orca-5.0.3 usando o método DFT com o funcional M06-2X e a base aug-cc-pVDZ definida na fase gasosa. Os resultados do docking molecular indicam que o ti-mol está ligado à proteína 3CL com uma energia de interação igual a -3.784 kcal/ mol. A análise QTAIM indica a presença de sítios de ligação críticos entre o timol e os resíduos HIS41 e CYS145. Além disso, observa-se a formação de uma ponte de hidrogênio entre o grupo OH do timol e o resíduo CYS145, o que é corroborado pelas análises ELF e NCI. Finalmente, o método NCI confirma a presença das interações de Van der Waals com o resíduo HIS41. Os resultados sugerem que o mecanismo de inibição da atividade da proteína 3CLpro é controlado por interações moleculares como ligações de hidrogênio e interações fracas.

Babaodan Alleviates APAP-induced Acute Liver Injury in Mice by Inhibiting NLRP3/Caspase-1 Pathway / 中国实验方剂学杂志

ObjectiveTo explore the effect of Babaodan （BBD） on the NOD-like receptor pyrin domain containing 3/cysteine aspartate-specific protease-3 （NLRP3/Caspase-1） pathway proteins in mice with acetaminophen （APAP）-induced acute liver injury. MethodC57BL/6 mice were randomly grouped， and BBD （75， 150， 300 mg·kg-1， ig） was administered twice a day for three days. After 2 hours of the last administration， the mice were treated with APAP （400 mg·kg-1， ip）， and the eyeballs were removed to collect blood after 14 hours. Then they were sacrificed by cervical dislocation for sample collection. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of liver tissue cells， and biochemical methods were used to detect the activities of alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， superoxide dismutase （SOD）， malondialdehyde （MDA） and myeloperoxidase （MPO） in serum of mice in each group. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was performed to determine the mRNA expression of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β） and IL-6， and Western blot was performed to determine the protein expression of cyclooxygenase-2 （COX-2）， inducible nitric oxide synthase （iNOS）， NLRP3， Caspase-1 and IL-18 in the liver of mice. ResultCompared with the conditions in normal group， the hepatic lobule structure of mice in the model group was partially destroyed， and the hepatic sinusoids were dilated. And the expression levels of ALT and AST in serum， the protein levels of NLRP3， Caspase-1， iNOS， IL-18 and COX-2 and the mRNA levels of IL-1β， IL-6 and TNF-α were increased （P<0.05， P<0.01）. Compared with the model group， the administration groups had improvement in liver cell rupture and hepatic sinusoidal compression， and a dose-dependent decrease in the levels of ALT and AST in serum as well as the protein levels of NLRP3， Caspase-1， iNOS， IL-18 and COX-2 and the the mRNA levels of IL-1β， IL-6 and TNF-α in liver tissue （P<0.05， P<0.01）. ConclusionBBD can reduce APAP-induced acute liver injury in mice. The mechanism may be related to anti-oxidative stress， inhibition of NLRP3/Caspase-1 pathway， and decreased expression levels of IL-1β， IL-18， TNF-α and IL-6.

Study on the role and mechanism of osteogenesis induced by advanced platelet-rich fibrin and β-tricalcium phosphate complex / 口腔疾病防治

Objective @#To investigate the role and mechanism of bone formation caused by the ratio of advanced platelet-rich fibrin (A-PRF) and β-tricalcium phosphate (β-TCP) in rabbit femur defect model, which provides a new idea for clinical treatment of bone defect.@*Methods @#Twenty-four New Zealand white rabbits were divided into model group, 1∶1 complex group (A-PRF∶β-TCP=1∶1), 2∶1 complex group (A-PRF∶β- TCP=2∶1) and 4∶1 complex group (A-PRF∶β- TCP=4∶1）, with 6 rabbits in each group. Femoral defect models were constructed in each group. In the composite group, the bone defect was filled with composite material, while in the model group, no material was filled. After 8 weeks, the animals were euthanized and specimens were collected. Bone mineral density (BMD), bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.SP) and trabecular number (Tb.N) in femoral defect tissue were measured by micro-CT and photographed. Hematoxylin - eosin staining was used to detect the pathological changes of new bone tissue. The morphological changes of the new bone tissue were observed by scanning electron microscopy. Determination of phospho-mitogen activated protein kinase p38 (p-p38MAPK), CCAAT/enhancer binding protein homologous protein (CHOP) and phospho-cysteine aspartic protease-3 (p-Caspase3) in newborn femur by ELISA. The mRNA expressions of osteoprotegerin (OPG), bone morphogenetic protein-2 (BMP-2), receptor activator of nuclear factor kappa-B ligand (RANKL) and p38MAPK were detected by real-time quantitative PCR. The expression of OPG, BMP-2, RANKL, p-p38MAPK and p-Caspase3 protein in the new bone tissue was observed by immunohistochemistry. @*Results @#In the model group, bone formation in the femoral defect area was slow and osteogenic quality was poor. Compared with the model group, the bone formation and neocapillaries of femoral defect area in the complex group was good, BMD, BV.TV, Tb.Th, Tb.N were increased, and Tb.Sp were decreased, the expressions of p-p38MAPK, CHOP and p-Caspase3 were decreased, and the mRNA and protein expressions of OPG and BMP-2 were increased. The mRNA expression of RANKL and p38MAPK was decreased. Apoptosis in new bone tissue of each group showed the lowest apoptosis rate in samples of the 2∶1 complex group (P<0.05); A-PRF: β-TCP=2∶1 ratio has the best osteogenic effect. @*Conclusion@#The complex composed of A-PRF and β-TCP can promote the expression of OPG, inhibit the expression of RANKL and phosphorylation of p38MAPK, reduce the apoptosis of new bone tissue cells, and promote osteogenic differentiation.

The expression and significance of protease activated receptor 2 in ovarian epithelial carcinoma / 中华肿瘤杂志

Objective: To investigate the expression and significance of protease activated receptor 2 (PAR2) in ovarian epithelial carcinoma. Methods: PAR2 mRNA expression levels in 410 cases of epithelial ovarian carcinoma and 88 cases of human normal ovary were analyzed from cancer Genome Atlas (TCGA) database and tissue genotypic expression database (GTEx). Immunohistochemical (IHC) staining of PAR2 protein was performed in 149 patients with ovarian cancer who underwent primary surgical treatment at Cancer Hospital of Chinese Academy of Medical Sciences. Then the relationship between mRNA/protein expression of PAR2 and clinicopathological features and prognosis was analyzed. Gene functions and related signaling pathways involved in PAR2 were studied by enrichment analysis. Results: The mRNA expression of PAR2 in epithelial ovarian carcinoma was significantly higher than that in normal ovarian tissue (3.05±0.72 vs. 0.33±0.16, P=0.004). There were 77 cases showing positive and 19 showing strong positive of PAR2 IHC staining among the 149 patients, accounting for 64.4% in total. PAR2 mRNA/protein expression was closely correlated with tumor reduction effect and initial therapeutic effect (P<0.05). Survival analysis showed that the progression free survival time (P=0.033) and overall survival time (P=0.011) in the group with high PAR2 mRNA expression was significantly lower than that in the low PAR2 mRNA group. Multivariate analysis showed tumor reduction effect, initial therapeutic effect were independent prognostic factors on both progression-free survival and overall survival (P<0.05). The progression-free survival (P=0.016) and overall survival (P=0.038) of the PAR2 protein high expression group was significantly lower than that of the low group. Multivariate analysis showed PAR2 expression, initial treatment effect and chemotherapy resistance were independent prognostic factors on both progression-free survival and overall survival (P<0.05). Based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), PAR2 target genes were mainly enriched in function related to intercellular connection, accounting for 40%. Gene enrichment analysis (GSEA) showed that the Wnt/β-catenin signaling pathway (P=0.023), the MAPK signaling pathway (P=0.029) and glycolysis related pathway (P=0.018) were enriched in ovarian cancer patients with high PAR2 mRNA expression. Conclusions: PAR2 expression is closely related to tumor reduction effect, initial treatment effect and survival of ovarian cancer patients. PAR2 may be involved in Wnt/β-catenin signaling pathway and intercellular connection promoting ovarian cancer invasion and metastasis.

Hypoxia-induced ROS aggravate tumor progression through HIF-1α-SERPINE1 signaling in glioblastoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Hypoxia, as an important hallmark of the tumor microenvironment, is a major cause of oxidative stress and plays a central role in various malignant tumors, including glioblastoma. Elevated reactive oxygen species (ROS) in a hypoxic microenvironment promote glioblastoma progression; however, the underlying mechanism has not been clarified. Herein, we found that hypoxia promoted ROS production, and the proliferation, migration, and invasion of glioblastoma cells, while this promotion was restrained by ROS scavengers N-acetyl-L-cysteine (NAC) and diphenyleneiodonium chloride (DPI). Hypoxia-induced ROS activated hypoxia-inducible factor-1α (HIF-1α) signaling, which enhanced cell migration and invasion by epithelial-mesenchymal transition (EMT). Furthermore, the induction of serine protease inhibitor family E member 1 (SERPINE1) was ROS-dependent under hypoxia, and HIF-1α mediated SERPINE1 increase induced by ROS via binding to the SERPINE1 promoter region, thereby facilitating glioblastoma migration and invasion. Taken together, our data revealed that hypoxia-induced ROS reinforce the hypoxic adaptation of glioblastoma by driving the HIF-1α-SERPINE1 signaling pathway, and that targeting ROS may be a promising therapeutic strategy for glioblastoma.

Bioinformatics analysis and prokaryotic expression of Strongyloides stercoralis serine protease inhibitor 1 / 中国血吸虫病防治杂志

Objective To predict the structure and antigenic epitope of the Strongyloides stercoralis serine protease inhibitor 1 (Ss-SRPN-1) protein using bioinformatics tools, and to construct prokaryotic expression plasmids for expression of recombinant Ss-SRPN-1 protein, so as to provide the basis for unraveling the function of the Ss-SRPN-1 protein. Methods The amino acid sequence of the Ss-SRPN-1 protein was downloaded from the NCBI database, and the physicochemical properties, structure and antigenic epitopes of the Ss-SRPN-1 protein were predicted using bioinformatics tools, including ExPASy, SWISS-MODEL and Protean. Primers were designed according to the nucleotide sequences of Ss-SRPN-1, and the Ss-SRPN-1 gene was amplified, cloned and sequenced with genomic DNA extracted from the infective third-stage larvae of S. stercoralis as a template. The Ss-SRPN-1 protein sequence was cloned into the pET28a (+) expression vector and transformed into Escherichia coli BL21 (DE) cells for induction of the recombinant Ss-SRPN-1 protein expression. The recombinant Ss-SRPN-1 protein was then purified and identified using Western blotting and mass spectrometry. Results Bioinformatics analysis showed that the Ss-SRPN-1 protein, which was composed of 372 amino acids and had a molecular formula of C1948H3046N488O575S16, was a stable hydrophilic protein, and the subcellular localization of the protein was predicted to be extracellular. The Ss-SRPN-1 protein was predicted to contain 11 dominant B-cell antigenic epitopes and 20 T-cell antigenic epitopes. The Ss-SRPN-1 gene with a length of 1 119 bp was successfully amplified, and the recombinant plasmid pET28a (+)/Ss-SRPN-1 was constructed and transformed into E. coli BL21(DE) cells. The expressed recombinant Ss-SRPN-1 protein had a molecular weight of approximately 43 kDa, and was characterized as a Ss-SRPN-1 protein. Conclusions The recombinant Ss-SRPN-1 protein has been expressed successfully, and this recombinant protein may be a potential vaccine candidate against strongyloidiasis.

Screening methods of SARS-CoV-2 main protease inhibitors and current applications / 药学学报

COVID-19 epidemic continues to spread around the world till these days, and it is urgent to develop more safe and effective new drugs. Due to the limited P3 biosafety laboratories for directly screening inhibitors of virulent viruses with high infectivity, it is necessary to develop rapid and efficient screening methods for viral proteases and other related targets. The main protease (Mpro), which plays a key role in the replication cycle of SARS-CoV-2, is highly conserved and has no homologous proteases in humans, making it an ideal target for drug development. From two different levels, namely, molecular level and cellular level, this paper summarizes the reported screening methods of SARS-CoV-2 Mpro inhibitors through a variety of representative examples, expecting to provide references for further development of SARS-CoV-2 Mpro inhibitors.

Progresses and analysis in fibrinolytic drugs induced hemorrhage / 药学学报

At present, most clinical thrombolytic drugs are plasminogen activators, which are highly dependent on the plasminogen level of the patient. Therefore, the efficacy of those drugs is restricted. Unlike the conventional thrombolytic plasminogen activator drugs, fibrinolytic drugs have direct fibrinolytic activity. Thus, fibrinolytic drugs can directly dissolve the thrombus, and its thromlysis efficacy is not restricted by the patients' plasminogen. This is a new type of thrombolytic drug with higher thrombolytic efficiency and safety, and has become one of the research hotspots at present. Although more and more agents that can be used as fibrinolytic drugs have been discovered, only a few of them can successfully be applied in clinical practice. The mainly underlying reason is the risk of bleeding. In this paper, based on the latest research progress of fibrinolytic drugs, the bleeding mechanisms and coping strategies of fibrinolytic drugs were systematically reviewed, five types of bleeding mechanisms of fibrinolytic drugs were summarized, and three types of coping strategies were proposed. We hope our work can provide theoretical basis for the development of safer and more efficient fibrinolytic drugs.

Biochemical properties of Scedosporium aurantiacum extracellular elastase-like protease / 生物工程学报

Extracellular elastase-like protease is one of the key virulence proteases of Scedosporium aurantiacum. To date, little is known about this enzyme in terms of genetic information, structure, properties and virulence mechanism due to the difficulties in purification caused by its low secretion amount, high specific activity, uncompleted genome sequencing and annotation. This work investigated the gene, structure and enzymatic properties of this enzyme. The S. aurantiacum elastase-like protease from the fungal culture supernatant was analyzed through tandem mass spectrometry (MS/MS) approach, illustrating its primary structure. Bioinformatics tools were employed to predict the conserved domain and tertiary structure, the enzymatic properties were also studied. It turned out that S. aurantiacum extracellular elastase-like protease demonstrated well hydrolysis towards elastin and bovine achilles tendon collagen, with Vmax of 18.14 μg/s and 17.57 μg/s respectively, better than fish scale gelatin, with the lowest hydrolysis effect on casein. Its activity towards elastin was lower than that of the elastase from porcine pancreas, with values of Kcat/Km of 3.541 (μg/s) and 4.091 (μg/s), respectively. It was an alkaline protease, with optimal pH 8.2 and temperature 37 oC. Zn2+ promoted the enzymatic activity while Ca2+, Mg2+, Na+, elastatinal and PMSF inhibited its activity. Its sequence was similar to Paecilomyces lilacinus secreted serine protease (PDB Entry: c3f7oB_) with multiple conserved fractions each containing more than 7 amino acids, thus suitable for design of PCR primer. This study increased our knowledge on S. aurantiacum extracellular elastase-like protease in terms of structure and enzymatic properties, and may facilitate later studies on protein expression and virulence mechanism.

Expression of BmSPI38 tandem multimers in Escherichia coli and its antifungal activity / 生物工程学报

The aim of this study was to prepare tandem multimeric proteins of BmSPI38, a silkworm protease inhibitor, with better structural homogeneity, higher activity and stronger antifungal ability by protein engineering. The tandem multimeric proteins of BmSPI38 were prepared by prokaryotic expression technology. The effects of tandem multimerization on the structural homogeneity, inhibitory activity and antifungal ability of BmSPI38 were explored by in-gel activity staining of protease inhibitor, protease inhibition assays and fungal growth inhibition experiments. Activity staining showed that the tandem expression based on the peptide flexible linker greatly improved the structural homogeneity of BmSPI38 protein. Protease inhibition experiments showed that the tandem trimerization and tetramerization based on the linker improved the inhibitory ability of BmSPI38 to microbial proteases. Conidial germination assays showed that His6-SPI38L-tetramer had stronger inhibition on conidial germination of Beauveria bassiana than that of His6-SPI38-monomer. Fungal growth inhibition assay showed that the inhibitory ability of BmSPI38 against Saccharomyces cerevisiae and Candida albicans could be enhanced by tandem multimerization. The present study successfully achieved the heterologous active expression of the silkworm protease inhibitor BmSPI38 in Escherichia coli, and confirmed that the structural homogeneity and antifungal ability of BmSPI38 could be enhanced by tandem multimerization. This study provides important theoretical basis and new strategies for cultivating antifungal transgenic silkworm. Moreover, it may promote the exogenous production of BmSPI38 and its application in the medical field.