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BACKGROUND AND PURPOSE:Vessel wall imaging can identify intracranial atherosclerotic plaque and give clues about its components. We aimed to investigate whether the plaque hyperintensity in the middle cerebral artery on T2-weighted vessel wall imaging is associated with ischemic stroke. MATERIALS AND METHODS:We retrospectively reviewed our institutional vessel wall MR imaging data base. Patients with an acute ischemic stroke within 7-day onset in the MCA territory were enrolled. Patients with stroke and stenotic MCA plaque (stenosis degree, ≥50%) were included for analysis. Ipsilateral MCA plaque was defined as symptomatic, and contralateral plaque, as asymptomatic. Plaque was manually delineated on T2-weighted vessel wall imaging. The plaque signal was normalized to the ipsilateral muscle signal. The thresholds and volume of normalized plaque signal were investigated using logistic regression and receiver operating characteristic analysis to determine the association between normalized plaque signal and stroke. RESULTS:One hundred eight stenotic MCAs were analyzed (from 88 patients, 66 men; mean age, 58 ± 15 years), including 72 symptomatic and 36 asymptomatic MCA plaques. Symptomatic MCA plaque showed larger plaque hyperintensity volume compared with asymptomatic MCA plaque. The logistic regression model incorporating stenosis degree, remodeling ratio, and normalized plaque signal 1.3-1.4 (OR, 6.25; 95% CI, 1.90-20.57) had a higher area under curve in differentiating symptomatic/asymptomatic MCA plaque, compared with a model with only stenosis degree and remodeling ratio (area under curve, 0.884 versus 0.806; P =.008). CONCLUSIONS:The MCA plaque hyperintensity on T2-weighted vessel wall imaging is independently associated with ischemic stroke and adds value to symptomatic MCA plaque classification. Measuring the normalized signal intensity may serve as a practical and integrative approach to the analysis of intracranial atherosclerotic plaque.

Objective: To explore the effect and underlying mechanism of increased expression of M-type phospholipase A 2 receptor (PLA 2 R) on podocyte membrane induced by hepatitis B virus X protein (HBx) on podocyte pyroptosis in hepatitis B virus-associated glomerulonephritis (HBV-GN). Methods: Transfection of the HBx gene into human kidney podocytes was used to mimic the HBV-GN pathogenesis process. Subsequently, podocytes were divided into the following eight groups: normal control plus secretory phospholipase A 2 -ⅠB (sPLA 2 -ⅠB) group, empty plasmid plus sPLA 2 -ⅠB group, HBx group, HBx plus sPLA 2 -ⅠB group, HBx plus sPLA 2 -ⅠB plus PLA 2 R control siRNA group, HBx plus sPLA 2 -ⅠB plus PLA 2 R-siRNA group, HBx plus sPLA 2 -ⅠB plus ROS control siRNA group, and HBx plus sPLA 2 -ⅠB plus ROS-siRNA group. Podocyte morphology was observed under a transmission electron microscope, and PLA 2 R expression was detected under a fluorescence microscope. Podocyte pyroptosis and reactive oxygen species (ROS) expression were analyzed by flow cytometry, and the mRNA and protein expression of PLA 2 R, nucleotide-binding oligomerization domain-like receptor 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1, interleukin (IL)-1β and IL-18 were determined by real-time fluorescence quantitative PCR and Western blot. Results: Compared with the control group, the expression of PLA 2 R on podocyte membrane significantly increased after transfection with HBx plasmid in vitro (4.07±0.41 vs 1.01±0.17, P <0.001). Transmission electron microscope and fluorochrome-labeled inhibitor of caspases/propidium iodide (FLICA/PI) double staining suggested that overexpressed PLA 2 R combined with sPLA 2 -ⅠB caused aggravated podocyte injury and increased pyroptosis (20.22%±0.36% vs 7.86%±0.28%, P <0.001). Moreover, the expression levels of ROS (4 324 515±222 764 vs 12 920±46, P <0.001), NLRP3 (48.30±2.73 vs 1.00±0.11, P <0.001), ASC (4.02±0.84 vs 1.01±0.15, P <0.001), caspase-1 (3.99±0.42 vs 1.00±0.11, P <0.001), IL-1β (9.08±0.75 vs 1.00±0.09, P <0.001) and IL-18 (19.20±0.70 vs 1.00±0.02, P <0.001) increased when PLA 2 R was overexpressed. In contrast, with the addition of PLA 2 R-siRNA or ROS-siRNA to knockdown the expression of related substances, podocyte injury was alleviated and the degree of pyroptosis decreased, and the expressions of genes related to the downstream signaling pathway (NLRP3, ASC, caspase-1, IL-1β and IL-18) decreased (all P <0.01). Conclusion: HBx may promote podocyte pyroptosis in HBV-GN by targeting the ROS-NLRP3 signaling pathway via the upregulation of PLA 2 R.

Background and Purpose: Vessel wall imaging can identify intracranial atherosclerotic plaque and give clues about its components. We aimed to investigate whether the plaque hyperintensity in the middle cerebral artery on T2-weighted vessel wall imaging is associated with ischemic stroke., Materials and Methods: We retrospectively reviewed our institutional vessel wall MR imaging data base. Patients with an acute ischemic stroke within 7-day onset in the MCA territory were enrolled. Patients with stroke and stenotic MCA plaque (stenosis degree, ≥50%) were included for analysis. Ipsilateral MCA plaque was defined as symptomatic, and contralateral plaque, as asymptomatic. Plaque was manually delineated on T2-weighted vessel wall imaging. The plaque signal was normalized to the ipsilateral muscle signal. The thresholds and volume of normalized plaque signal were investigated using logistic regression and receiver operating characteristic analysis to determine the association between normalized plaque signal and stroke., Results: One hundred eight stenotic MCAs were analyzed (from 88 patients, 66 men; mean age, 58 ± 15 years), including 72 symptomatic and 36 asymptomatic MCA plaques. Symptomatic MCA plaque showed larger plaque hyperintensity volume compared with asymptomatic MCA plaque. The logistic regression model incorporating stenosis degree, remodeling ratio, and normalized plaque signal 1.3-1.4 (OR, 6.25; 95% CI, 1.90-20.57) had a higher area under curve in differentiating symptomatic/asymptomatic MCA plaque, compared with a model with only stenosis degree and remodeling ratio (area under curve, 0.884 versus 0.806; P =.008)., Conclusions: The MCA plaque hyperintensity on T2-weighted vessel wall imaging is independently associated with ischemic stroke and adds value to symptomatic MCA plaque classification. Measuring the normalized signal intensity may serve as a practical and integrative approach to the analysis of intracranial atherosclerotic plaque., (© 2019 by American Journal of Neuroradiology.)

Module-based methods have made much progress in deconstructing biological networks. However, it is a great challenge to quantitatively compare the topological structural variations of modules (allosteric modules [AMs]) under different situations. A total of 23, 42, and 15 coexpression modules were identified in baicalin (BA), jasminoidin (JA), and ursodeoxycholic acid (UA) in a global anti-ischemic mice network, respectively. Then, we integrated the methods of module-based consensus ratio (MCR) and modified Z summary module statistic to validate 12 BA, 22 JA, and 8 UA on-modules based on comparing with vehicle. The MCRs for pairwise comparisons were 1.55% (BA vs. JA), 1.45% (BA vs. UA), and 1.27% (JA vs. UA), respectively. Five conserved allosteric modules (CAMs) and 17 unique allosteric modules (UAMs) were identified among these groups. In conclusion, module-centric analysis may provide us a unique approach to understand multiple pharmacological mechanisms associated with differential phenotypes in the era of modular pharmacology., (© 2016 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Aim: To clone the cDNA of UGT1A9 from a Chinese human liver and establish the Chinese hamster lung (CHL) cell line expressing human UGT1A9., Methods: cDNA of UGT1 A9 was transcripted from mRNA by reverse transcriptase-ploymerase chain reaction, and was cloned into the pGEM-T vector which was amplified in the host bacteric E.Coli DH5(alpha). The inserted fragment, verified by DNA sequencing, was subcloned into the Hind III /Not I site of a mammalian expression vector pREP9 to construct the plasmid termed pREP9-UGT1A9. CHL cells were transfected with the resultant recombinants, pREP9-UGT1A9, and selected by G418 (400 mg x L(-1)) for one month. The surviving clone (CHL-UGT1A9) was harvested as a pool and sub-cultured in medium containing G418 to obtain samples forUGT1A9 assays. The enzyme activity of CHL-UGT1A9 towards propranolol in S9 protein of the cell was determined by HPLC., Results: The sequence of the cDNA segment cloned, which was 1666 bp in length, was identical to that released by Gene Bank (GenBank accession number: AF056188) in coding region. The recombinant constructed, pREP9-UGT1A9, contains the entire coding region, along with 18 bp of the 5' and 55 bp of the 3' untranslated region of theUGT1A9 cDNA, respectively. The cell lines established expressed the protein of UGT1A9, and the enzyme activity towards propranolol in S9 protein was found to be 101+/- 24 pmol x min(-1) x mg(-1) protein (n=3), but was not detectable in parental CHL cells., Conclusion: The cDNA of UGT1A9 was successfully cloned from a Chinese human liver and transfected into CHL cells. The CHL-UGT1 A9 cell lines established efficiently expressed the protein ofUGT1A9 for the further enzyme study of drug glucuronidation.

Aim: To investigate the stereoselective metabolism of propafenone (PPF) by human liver CYP3A4., Methods: A chiral and an achiral HPLC were combined to determine the enantiomer of PPF in S9 incubates prepared from transgenic Chinese hamster CHL cells lines expressing CYP3A4. The time-dependent study was performed using individual enantiomer or racemate at low or high substrate concentration. Kinetic parameters were determined employing individual enantiomers as substrates. Enantiomeric inhibition experiments were performed by using R(-)-PPF as an inhibitor and S(+)-PPF as a substrate., Results: Stereoselectivity was found in metabolism of racemic PPF at low substrate concentration (10 mg/L) (S < R), and lost at high substrate concentration (400 mg/L) When an individual enantiomer of high concentration (200 mg/L) was used as a substrate, S(+)-PPF was eliminated faster than its isomer (S < R). However, the opposite situation was observed at low concentration (5 mg/L) (S < R). The Vmax of S(+)-PPF was significantly greater than that of R(-)-PPF [(2.66 +/- 0.32) vs (1.71 +/- 0.19) micromol . mg-1 . min-1]. The Km of R(-)-PPF was significantly lower than that of S(+)-PPF [(73 +/- 11) vs (185 +/- 17) micromol/L]. R(-)-PPF inhibited S(+)-isomer with an IC50 value of 125 micromol . L-1., Conclusion: It is concluded that stereoselectivity in metabolism of propafenone via CYP3A4 depend on substrate concentration. Enantiomer/enantiomer interaction of PPF occurred at high concentration of substrate, and resulted in the loss of stereoselectivity. There maybe no enantiomer/enantiomer interaction at low concentration thus keeping the superiority of R(-)-PPF in metabolism.

The compositions and contents of amino acids of parasites in different areas of China have been determined by precolumn derivatization, reversed-phase high performance liquid chromatography (HPLC) separation and ultra-violet absorption quantitation in order to prevent diseases caused from parasites. The results show that there were some differences in contents of amino acids in B. malayi from seven different areas in China. The contents of amino acids gradually increased from the southern to the northern areas in China. The method is simple and accurate, and the results have important values to investigate the life activities of parasites.

Bilirubin is a toxic substance. In order to effectively remove it from the hepatic patients' blood, two novel affinity membranes were prepared. These were prepared by chemically grafting on cellulose and immobilized with different ligands. One kind of ligand was poly-D-lysine, the other one was quaternary ammonium salt. Both affinity membranes were used for removal bilirubin from phosphate buffer and HSA solutions, and the effects of temperature, HSA concentration, adsorption time in static state experiment and flow rate in dynamic state experiment have been investigated. The results indicated that the membranes could remove over 70% bilirubin from phosphate buffer and at least 50% from low concentration HSA solutions. The results also indicated that the removal efficiency was better at higher temperature. In the static state experiment, four hours can be selected as adsorption time. In the dynamic state experiment, the flow rate can be properly increased.

Phage exclusion is a form of programmed cell death in prokaryotes in which death is triggered by infection with phage, a seemingly altruistic response that limits multiplication of the phage and its spread through the population. One of the best-characterized examples of phage exclusion is the exclusion of T-even phages such as T4 by the e14-encoded Lit protein in many Escherichia coli K-12 strains. In this exclusion system, transcription and translation of a short region of the major head coat protein gene late in phage infection activates proteolysis of translation elongation factor Tu (EF-Tu), blocking translation and multiplication of the phage. The cleavage occurs between Gly-59 and Ile-60 in the nucleotide-binding domain. In the present work, we show that a 29-residue synthetic peptide spanning the activating region of the major head coat protein can activate the cleavage of GDP-bound EF-Tu in a purified system containing only purified EF-Tu and purified Lit protein. Lit behaves as a bona fide enzyme in this system, cleaving EF-Tu to completion when present at substoichiometric amounts. Two mutant peptides with amino acid changes that reduce the activation of cleavage of EF-Tu in vivo were also greatly reduced in their ability to activate EF-Tu cleavage in vitro but were still able to activate cleavage at a high concentration. Elongation factor G, which has the same sequence at the cleavage site and a nucleotide-binding domain similar to EF-Tu, was not cleaved by this system, and neither was heat-inactivated EF-Tu, suggesting that the structural context of the cleavage site may be important for specificity. This system apparently represents an activation mechanism for proteolysis that targets one of nature's most evolutionarily conserved proteins for site-specific cleavage.

It was found that modified pulse induction could produce SOS responses of the sfi gene in 15 minutes. The responses peaked at 30-60 minutes and were twice as strong as those by persistent induction. The modified pulse induction could therefore more truly reflect the inducing effect. However, the SOS-inducing kinetics of MMC and 4NQO was not identical suggesting distinct kinetic patterns of induction by different mutagens. A suppressive effect on 4NQO-induced SOS response by cinnamic aldehyde and diallyl trisulfate was also observed. The effect might be due to an interference with the metabolic activation of 4NQO or breakdown of 4NQO by the bacteria.