Molecular dynamics simulation technology relies on Newtonian mechanics to simulate the motion of molecular system of the real system by computer simulation. It has been used in the research of self-assembly processes illustration and macroscopic performance prediction of self-assembly nano-drug delivery systems (NDDS) in recent years, which contributes to the facilitation and accurate design of preparations. In this review, the definitions, catalogues, and the modules of molecular dynamics simulation techniques are introduced, and the current status of their applications are summarized in the acquisition and analysis of microscale information, such as particle size, morphology, the formation of microdomains, and molecule distribution of the self-assembly NDDS and the prediction of their macroscale performances, including stability, drug loading capacity, drug release kinetics and transmembrane properties. Moreover, the existing applications of the molecular dynamic simulation technology in the formulation prediction of self-assembled NDDS were also summarized. It is expected that the new strategies will promote the prediction of NDDS formulation and lay a theoretical foundation for an appropriate approach in NDDS studies and a reference for the wider application of molecular dynamics simulation technology in pharmaceutics.

Mice ; Animals ; Tandem Mass Spectrometry ; Alpha-Amanitin ; Chromatography, Liquid ; Metabolomics ; Chromatography, High Pressure Liquid/methods*

Aim To elucidate the molecular mechanism of Sophora tonkinensis Gagnep in improving acute pharyngitis based on network pharmacology, animal experiments and quantitative real-time PCR.Methods The active components and targets of Sophora tonkinensis Gagnep were collected from the database of traditional Chinese medicinal systems databases and analysis platform(TCMSP). Targets related to acute pharyngitis were acquired through GeneCards, OMIM, DrugBank and Disgenet databases. After the common targets of the two were screened, the STRING database was used to construct the protein interaction network, and the Metascape platform was used for pathway analysis. At the same time, Cytoscape software was used to construct a network of "herbal-disease-component-target" and "herbal-disease-component-target-pathway" network. The acute pharyngitis models in rats were established to study the effect of water extract of Sophora tonkinensis Gagnep on acute pharyngitis in rats. Quantitative real-time PCR technology was used to study the effect of Sophora tonkinensis Gagnep on key gene targets in key pathways of pharyngeal tissues in rats with acute pharyngitis. Results In this experiment, 509 related targets of 21 active components of Sophora tonkinensis Gagnep were obtained, 2 167 related targets of acute pharyngitis were obtained, and 194 common targets of Sophora tonkinensis Gagnep and acute pharyngitis were obtained. KEGG pathway analysis screened 344 related signaling pathways, indicating that IL-17 signaling pathway, NF-kappa B signaling pathway and leukocyte transendothelial migration pathway might play a key role in the improvement of acute pharyngitis by Sophorae tonkinensis Gagnep. Animal experiments showed that the low dose group of Sophora tonkinensis Gagnep water extract had better therapeutic effect on acute pharyngitis. The results of quantitative real-time PCR showed that the low-dose group of Sophora tonkinensis Gagnep significantly down-regulated the expression levels of ITGB2, PIK3CA, PIK3CD and PTPN11 genes in leukocyte transendothelial migration pathway(P<0.05). Conclusions The above results show that Sophora tonkinensis Gagnep has the characteristics of multi-component, multi-target and multi-pathway synergy in improving acute pharyngitis, which provides a theoretical basis for further study on the complex mechanism of Sophora tonkinensis Gagnep in improving acute pharyngitis.

Aim To investigate the mechanism of Sophorae tonkinensis radix et rhizome (ST) induced nephrotoxicity based on network toxicology and experimental verification. Methods Through network toxicology the target of toxic components of ST was predicted, nephrotoxicity-related target genes were located, the intersection of targets was taken, the STRING platform was imported to map the target protein interactions, MetaScape database was used for GO and KEGG analysis, BioGPS database for screening the key expressed genes in rat nephrotoxicity and the component-target-pathway network was constructed. The mechanism of ST induced nephrotoxicity was verified through animal experiments, and qRT-PCR was applied to detect mRNA expression level of key genes in kidney tissue. Results Twenty toxic components of ST were screened from network toxicology, mainly including matrine, sophoridine, maackiain. A total of 135 targets were involved, and HSP90AA1, SRC, MAPK1, MAPK3, AKT1 were the main targets. A total of 169 related signaling pathways were yielded by KEGG analysis, and the mechanism of nephrotoxicity might be related to cancer pathway, PI3K-Akt signaling pathway, HIF-1 signaling pathway, MAPK signaling pathway. PPARA, RAF1, MAP2K1, SRC, AKT1 and MAPK3 were screened from BioGPS database. The results of animal experiments showed that BUN and SCr level increased (P <0. 01) in rats with high-dose group, and the kidney tissue was significantly damaged. qRT-PCR results indicated that the expression of PPARA, RAF1, MAP2K1, MAPK3 mRNA increased, the expression of AKT1 mRNA decreased in the high-dose group of ST (P <0. 05). Conclusions The mechanism of Sophorae tonkinensis radix et rhizome induced nephrotoxicity is found to be related to the combined action of multiple components, multiple targets and multiple pathways, which also provides a theoretical basis for the in-depth exploration of the toxicology.

OBJECTIVE: Severe cases of coronavirus disease 2019 (COVID-19) are expected to have a worse prognosis than mild cases. Shenhuang Granule (SHG) has been shown to be a safe and effective treatment for severe COVID-19 in a previous randomized clinical trial, but the active chemical constituents and underlying mechanisms of action remain unknown. The goal of this study is to explore the chemical basis and mechanisms of SHG in the treatment of severe COVID-19, using network pharmacology. METHODS: Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry was employed to screen chemical constituents of SHG. Putative therapeutic targets were predicted by searching traditional Chinese medicine system pharmacology database and analysis platform, SwissTargetPrediction, and Gene Expression Omnibus (GEO) databases. The target protein-protein interaction network and enrichment analysis were performed to investigate the hub genes and presumptive mechanisms. Molecular docking and molecular dynamics simulations were used to verify the stability and interaction between the key chemical constituents of SHG and COVID-19 protein targets. RESULTS: Forty-five chemical constituents of SHG were identified along with 131 corresponding therapeutic targets, including hub genes such as HSP90AA1, MMP9, CXCL8, PTGS2, IFNG, DNMT1, TYMS, MDM2, HDAC3 and ABCB1. Functional enrichment analysis indicated that SHG mainly acted on the neuroactive ligand-receptor interaction, calcium signaling pathway and cAMP signaling pathway. Molecular docking showed that the key constituents had a good affinity with the severe acute respiratory syndrome coronavirus 2 protein targets. Molecular dynamics simulations indicated that ginsenoside Rg4 formed a stable protein-ligand complex with helicase. CONCLUSION Multiple components of SHG regulated multiple targets to inhibit virus invasion and cytokine storm through several signaling pathways; this provides a scientific basis for clinical applications and further experiments.
Humans ; Molecular Docking Simulation ; Ligands ; Network Pharmacology ; Drugs, Chinese Herbal/chemistry* ; Medicine, Chinese Traditional ; COVID-19 Drug Treatment

Objective: Comparative analyses of wild-type Clostridioides difficile 630 (Cd630) strain and pathogenicity locus (PaLoc) knockout mutant (ΔPaLoc) by using RNA-seq technology. Analysis of differential expression of Cd630 wild-type strain and ΔPaLoc mutant strain and measurement of its cellular virulence changes. Lay the foundation for the construction of an toxin-attenuated vaccine strain against Clostridioides difficile. Methods: Analysis of Cd630 and ΔPaLoc mutant strains using high-throughput sequencing (RNA-seq). Clustering differentially expressed genes and screening differentially expressed genes by DESeq software. Further analysis of differential genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Finally, cytotoxicity assays of ΔPaLoc and Cd630 strains were performed in the African monkey kidney epithelial cell (Vero) and the human colonic cell (Caco-2) lines. Results: The transcriptome data showed that the ΔPaLoc mutant toxin genes tcdA and tcdB were not transcribed. Compared to the wild-type strain, CD630_36010, CD630_020910,CD630_02080 and cel genes upregulated 17.92,11.40,8.93 and 7.55 fold, respectively. Whereas the hom2 (high serine dehydrogenase), the CD630_15810 (spore-forming protein), CD630_23230 (zinc-binding dehydrogenase) and CD630_23240 (galactitol 1-phosphate 5-dehydrogenase) genes were down-regulated by 0.06, 0.075, 0.133 and 0.183 fold, respectively. The GO and KEGG enrichment analyses showed that the differentially transcribed genes in ΔPaLoc were enriched in the density-sensing system, ABC transport system, two-component system, phosphotransferase (PTS) system, and sugar metabolism pathway, as well as vancomycin resistance-related pathways. Cytotoxicity assays showed that the ΔPaLoc mutant strain lost its virulence to Vero and Caco-2 cells compared to the wild-type Cd630 strain. Conclusion: Transcriptional sequencing analysis of the Cd630 and ΔPaLoc mutant strains showed that the toxin genes were not transcribed. Those other differential genes could provide a reference for further studies on the physiological and biochemical properties of the ΔPaLoc mutant strain. Cytotoxicity assays confirmed that the ΔPaLoc mutant lost virulence to Vero and Caco-2 cells, thus laying the foundation for constructing an toxin-attenuated vaccine strain against C. difficile.
Bacterial Proteins/metabolism* ; Bacterial Toxins/metabolism* ; Caco-2 Cells ; Clostridioides ; Clostridioides difficile/genetics* ; Humans ; Oxidoreductases/metabolism* ; Transcriptome ; Vaccines, Attenuated

OBJEC TIVE To optimize the simultaneous extraction technology of dietary fiber （DF）and flavonoids from the peel of Prunus armeniaca . METHODS The content of DF was calculated with enzyme-gravimetric method ，and the content of flavonoids was determined by ultraviolet spectrophotometry. The orthogonal design and single factor test were used to optimize the extraction technology ，with the factors of liquid-solid ratio ，pH，papain concentration ，α-amylase concentration ，temperature of enzymatic hydrolysis and time of enzymatic hydrolysis as factors ，using the contents of DF and flavonoids as indexes. RESULTS The optimal extraction technology included the solid-liquid ratio of 1 ∶ 10（g/mL），pH5，0.5％ papain and 0.5％ α-amylase， enzymatic hydrolysis at 50 ℃ for 1 h. After three times of validation ，the average content of DF was 0.801 g/g（RSD＝1.95％）， and the average content of flavonoids was 2.135 mg/g（RSD＝2.44％）. The average comprehensive score was 0.988（RSD＝ 0.81％）. CONCLUSIONS The optimal extraction technology is stable and feasible.

Since the implementation of drug registration in China, the classification of Chinese medicine has greatly met the needs of public health and effectively guided the transformation, inheritance, and innovation of research achievements on traditional Chinese medicine(TCM). In the past 30 years, the development of new Chinese medicine has followed the registration transformation model of " one prescription for single drug". This model refers to the R&D and registration system of modern drugs, and approximates to the " law-abiding" medication method in TCM clinic, while it rarely reflects the sequential therapy of syndrome differentiation and comprehensive treatment with multiple measures. In 2017, Opinions on Deepening the Reform of Review and Approval System and Encouraging the Innovation of Drugs and Medical Devices released by the General Office of the CPC Central Committee and the General Office of the State Council pointed out that it is necessary to " establish and improve the registration and technical evaluation system in line with the characteristics of Chinese medicine, and handle the relationship between the traditional advantages of Chinese medicine and the requirements of modern drug research". Therefore, based on the development law and characteristics of TCM, clinical thinking should be highlighted in the current technical requirements and registration system of research and development of Chinese medicine. Based on the current situation of registration supervision of Chinese medicine and the modern drug research in China, the present study analyzed limitations and deficiency of " one prescription for single drug" in the research and development of Chinese medicine. Additionally, a new type of " series prescriptions" was proposed, which was consistent with clinical thinking and clinical reality. This study is expected to contribute to the independent innovation and high-quality development of the TCM industry.
China ; Drugs, Chinese Herbal/therapeutic use* ; Medicine, Chinese Traditional ; Prescriptions ; Public Health

This manuscript aims to investigate the effects of resibufogenin on the proliferation, migration and invasion of human hepatocellular carcinoma cells and its related mechanisms. MTT assay was used to determine the inhibitory effect of resibufogenin on the growth of four hepatocellular carcinoma cells in vitro. Wound-healing assay and Transwell assay were used to evaluate the migration and invasion ability of resibufogenin on MHCC-97H cells. Western blot assay was used to detect the expression of migration and invasion related proteins in MHCC-97H cells treated with different concentrations of resibufogenin. The results showed that resibufogenin significantly inhibited the proliferation of hepatocellular carcinoma cells in vitro. The half maximal inhibitory concentration (IC₅₀) values on MHCC-97H, HepG2, SK-Hep-1 and Huh-7 cells were 0.55 ± 0.06, 2.83 ± 0.24, 5.25 ± 0.49, 14.89 ± 2.28 μmol·L^-1, respectively. Resibufogenin also suppressed the migration and invasion of MHCC-97H cells in a concentration-dependent manner. The protein expression of integrin α2, integrin α6, integrin β1, N-cadherin, matrix metalloproteinase 2 (MMP2) and transcription factor Twist in MHCC-97H cells were decreased significantly with the increase of the concentration of resibufogenin, while the protein expression of E-cadherin increased. In addition, we found that p-PI3K/PI3K and p-AKT/AKT ratios were significantly reduced after treatment with resibufogenin. In conclusion, resibufogenin can inhibit the proliferation, migration and invasion of hepatocellular carcinoma MHCC-97H cells in vitro, which is related to the regulation of intracellular migration and invasion protein expression and PI3K/AKT signaling pathway.

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases