Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

Objective:To explore the relationship between diffusion tensor imaging (DTI) parameter of fractional anisotropy (FA) and recovery of upper-extremity motor function in patients with ischemic stroke. Methods:From January to December, 2019, 20 ischemic stroke patients accepted routine medication and rehabilitation for three weeks. They received DTI examination and were measured FA of the infarct and the corresponding area on the contralateral side, the cerebral foot and the posterior limb of internal capsule of affected and unaffected sides, while the bilateral FA ratio (rFA) of them were calculated, before and after treatment. Meanwhile, all the patients were assessed with Fugl-Meyer Assessment-Upper Extremity (FMA-UE). Results:The FMA-UE score improved after treatment (t = 9.074, P < 0.001), while FA and rFA increased in infarct area (t > 14.519, P < 0.001). The difference before and after treatment of FA and rFA in all of the areas positively correlated with that of FMA-UE scores (r = 0.445~0.565, P < 0.05), which was the most in posterior limb of internal capsule of the affected side. Conclusion:FA of DTI alters with the recovery of motor function of the upper extremity after ischemic stroke, especially in the posterior limb of internal capsule.

Objective To investigate the effects of 72 h sleep deprivation(SD)on circadian clock gene expression in the rat liver.Methods Twelve rats were randomly divided into control group and SD group.An SD instrument was used to deprive the rats′sleep for 72 h.Then the abdominal cavity was exposed to obtain liver,and the expression of clock genes was detected by RT-PCR and Western blotting analysis, respectively.Results Compared with the control group, the mRNA levels of clock,npas2 and rev-erbαstrikingly decreased in the livers of the SD group rats.However,per1,per2 and rorαmRNA levels obviously increased.bmal1 and cry1 mRNA expression hardly changed in the control and SD groups. Meanwhile,the protein levels of liver BMAL1,CLOCK,NPAS2,CRY1 and REV-ERBαwere significantly down-regulated and PER1,PER2 and RORαprotein levels were up-regulated in SD group compared with control group.Conclusion 72 h SD can result in abnormal expressions of several circadian clock genes in the rat liver at both transcriptional and translational levels.

Objective To investigate the effects of 72 h sleep deprivation (SD) on circadian clock gene expression in the rat spleen.Methods The rats were randomly divided into control group and SD group.An SD instrument was used to deprive the rats of sleep for 72 h.Then the lymphocytes from the spleen were obtained by Ficoll seperation medium before the expression of clock genes was detected by RT-PCR and Western blotting analysis respectively.Results Compared with the control group,the mRNA levels of bmal1,clock,per2 and rev-erbα strikingly decreased in the spleens of the SD group rats.However,npas2,per1,rorα and cry1 mRNA expression hardly changed in the control and SD group.Meanwhile,the protein levels of spleen BMAL1,NPAS2,CRY1 and RORα were significantly down-regulated and PER1 protein levels were up-regulated in SD group compared with control group.However REV-ERBα protein expression remained unchanged in the control and SD group.Conclusion 72 h SD can result in abnormal expressions of several circadian clock genes in lymphocytes of the spleen at both transcription and translation levels.

Boiling processing is commonly used in post-harvest handling of White Paeony Root (WPR), in order to whiten the herbal materials and preserve the bright color, since such WPR is empirically considered to possess a higher quality. The present study was designed to investigate whether and how the boiling processing affects overall quality of WPR. First, an ultra-high performance liquid chromatography quadrupole/time-of-flight mass spectrometry-based metabolomics approach coupled with multivariate statistical analysis was developed to compare the holistic quality of boiled and un-boiled WPR samples. Second, ten major components in WPR samples boiled for different durations were quantitatively determined using high performance liquid chromatography to further explore the effects of boiling time on the holistic quality of WPR, meanwhile the appearance of the processed herbal materials was observed. The results suggested that the boiling processing conspicuously affected the holistic quality of WPR by simultaneously and inconsistently altering the chemical compositions and that short-time boiling processing between 2 and 10 min could both make the WPR bright-colored and improve the contents of major bioactive components, which were not achieved either without boiling or with prolonged boiling. In conclusion, short-term boiling (2-10 min) is recommended for post-harvest handling of WPR.
Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; chemistry ; standards ; Hot Temperature ; Mass Spectrometry ; methods ; Paeonia ; chemistry ; Plant Roots ; chemistry ; Technology, Pharmaceutical ; Water

OBJECTIVETo observe the effect of Zishen Huoxue Recipe (ZHR) on pathomorphology in coronary heart disease (CHD) rats with Shen deficiency blood stasis syndrome (SDBSS).

METHODSTotally 60 healthy Wistar rats were divided into the blank control group, the model group, high, middle, and low dose ZHR groups according to random digit table, 12 in each group. Myocardial ischemia SDBSS rat model was prepared by ligating the left anterior descending coronary artery and injecting hydrocortisone. ZHR physic liquor was administered to rats in high, middle, and low dose ZHR groups at the daily dose of 21.6, 10.8, 5.4 g/kg by gastrogavage for 7 successive days, equal volume of pure water was administered to rats in the blank control group and the model group by gastrogavage for 7 successive days. Rat heart was collected for pathomorphological observation under light microscope.

RESULTSIn the model group the heart muscle fiber was swollen and deformed with widened space, loose and dropsy tissues. Blood vessels in myocardial mesenchymal were dilated, infiltrated with more inflammatory cells. Myocardial cells were markedly swollen, degenerated, or necrotic, with caryolysis or disappearance of partial nuclear. A large amount of collagen fibrous tissue became hyperplasia. Endocardial blood vessels were swollen and degenerated with infiltration of few inflammatory cells. Epicardium tissue and structure were destroyed and got hyperplasia. Swollen, degenerated, or necrotic vessels could be seen, with infiltration of more inflammatory cells and collagen deposition. Pathomorphological injuries were alleviated in each ZHR group. The higher ZHR concentration, the milder the injury degree of myocardial tissue, the more limited range of damage.

CONCLUSIONZHR could attenuate pathomorphological injuries of myocardial ischemia rats with SDBSS and regulate myocardial function, thus improving myocardial ischemia in CHD rats with SDBSS.

Animals ; Coronary Artery Disease ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Medicine, Chinese Traditional ; Myocardial Ischemia ; Myocardium ; Rats ; Rats, Wistar

In this paper, we cloned the full-length cDNA of TwSQS from Tripterygium wilfordii suspension cells (GenBank:KR401220) and performed the bioinformation and mRNA expression analysis. The expression after methyl jasmonate (MJ) treatment of the gene was detected by RT-PCR. The full-length cDNA of TwSQS was 1800 bp containing a 1242 bp open reading frame (ORF) encoding a polypeptide of 413 amino acids. The theoretical isoelectric point (pI) was 7.94 and the calculate molecular weight was about 47.20 kD. The relative expression level of TwSQS was deduced by MJ and reached the highest at 4 h after the treatment. The gene information we got in this study enriched the biosynthesis pathway of triterpenoids in Tripterygium wilfordii and laid foundation for further studies.

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme:sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length cDNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (pI) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21 (DE3) competent cells. After methyl jasmonate treatment, the relative expression level of TwSMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, TwSMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.

4-(Cytidine-5-diphospho) -2-C-methyl-D-erythritol kinase is a key enzyme in the biosynthesis pathway of terpenoids. According to the transcriptome database, the specific primers were designed and used in PCR. The bioinformatic analysis of the sequenced TwCMK gene was performed in several bioinformatics software. The Real-time fluorescence quantification polymerase chain reaction (RT-qPCR) were used to detect the expression levels of TwCMK from T. wilfordii after elicitor MeJA supplied. The results showed that the full length of TwCMK cDNA was 1 732 bp encoding 387 amino acids. The theoretical isoelectric point of the putative TwCMK protein was 5.79 and the molecular weight was about 42.85 kDa. MeJA stimulated the rising of TwCMK expression in suspension cell and signally impacted at 24 h. The research provides a basis for further study on the regulation of terpenoid secondary metabolism and biological synthesis.
Amino Acid Sequence ; Cloning, Molecular ; Computational Biology ; Gene Expression Regulation, Plant ; Models, Molecular ; Molecular Sequence Data ; Phosphotransferases (Alcohol Group Acceptor) ; chemistry ; genetics ; metabolism ; Phylogeny ; Plant Proteins ; chemistry ; genetics ; metabolism ; Sequence Alignment ; Tripterygium ; chemistry ; enzymology ; genetics