Effects of Valeriana amurensis Roots and Rhizomes Extract and Its Active Constituents on Activities of Drug Metabolism Enzymes in Liver / 中国实验方剂学杂志

Objective::To evaluate the effects of Valeriana amurensis roots and rhizomes extract and its active constituents on the activities of six major cytochrome P450 (CYP450) enzymes in human liver microsomes. Method::Coumarin, bupropion, tolbutamide, omeprazole, dextromethorphan and testosterone were used as probe substrates for CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6 and CYP3A4, respectively. Taking their specific metabolites of hydroxylation or demethylation (7-hydroxycoumarin, hydroxybupropion, 4-hydroxytolbutamide, 5-hydroxyomeprazole, dextromethorphan, 6β-hydroxytestosterone) as indicators of enzyme activities. The analytical indexes were used to establish an in vitro model of human liver microsomes of Cocktail probe substrates. This method was applied to evaluate the effects of V. amurensis roots and rhizomes extract and its active constituents on human liver microsomal enzymes. Result::The V. amurensis roots and rhizomes extract had different inhibitory effects on CYP2B6, CYP2C9, CYP2D6 and CYP3A4, their half-inhibitory concentration (IC50) values were 87.49, 1.73, 68.29, 2.80 mg·L-1, respectively. Among the 9 lignans, (-)-massoniresinol-3α-O-β-D-glucopyranoside had a moderate inhibitory effect on CYP2A6 with an IC50 value of 8.51 μmol·L-1, 8, 8′-dihydroxypinoresinol-4, 4′-di-O-β-D-glucopyranoside had a moderate inhibitory effect on CYP2D6 with an IC50 value of 8.73 μmol·L-1, (+)-medioresinol-4, 4′-O-di-β-D-glucopyranoside had a moderate inhibitory effect on CYP2B6 and CYP2C9 with IC50 values of 5.41 μmol·L-1 and 8.20 μmol·L-1. Conclusion::The V. amurensis roots and rhizomes extract and its active constituents have inhibitory effects on liver CYP450 enzymes. Therefore, in the clinical study of new drugs, it is necessary to fully evaluate the risk of drug interactions caused by combination therapy.

Minimal invasive microscopic tooth preparation based on endodontic, periodontal and functional health / 华西口腔医学杂志

Tooth preparation is the primary and core operation technique for dental esthetic restoration treatment, due to its effect of providing restoration space, bonding interfaces and marginal lines for dental rehabilitation after tooth tissue reduction. The concept of microscopic minimal invasive dentistry put forward the issue of conducting high-quality tooth preparation, conserve tooth-structure, protect vital pulp and periodontal tissue simultaneously. This study reviewed the concepts, physiology background, design and minimal invasive microscopic tooth preparation, and in the meantime, individualized strategies and the two core elements of tooth preparation (quantity and shape) are listed.

Effect of hydrogen peroxide with different pH values on the color, translucency and laser-induced fluorescence of human dentin / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of 30% hydrogen peroxide(HP) with different pH values on color, translucency and laser-induced fluorescence of human dentin.</p><p><b>METHODS</b>Sixty dentin specimens from crown of mandibular third molars were randomly assigned into four groups (n = 15) and treated with acidic 30% HP, neutral 30% HP, alkaline 30% HP and deionized water (control group), respectively. The bleaching process was 0.5 h×4 times, and time points for measuring were baseline (0), 0.5, 1 and 2 h. A colorimeter was employed to measure the L(*), a(*), b(*) coordinates of dentin against white, black and yellow background. Then the parameters of translucency, masking effects, chroma and whiteness were calculated. The dentinal laser-induced Raman/fluorescence spectra was recorded by a Raman spectrometer and the fluorescence intensity(FI) and FI% were calculated.</p><p><b>RESULTS</b>ΔFI of acidic, neutral, alkaline 30% HP at 2 h were 9960.03 ± 2037.74, 8502.09 ± 1413.86, 8554.29 ± 1986.19. And ΔFI% were 84.60 ± 3.43, 84.89 ± 5.19, 86.72 ± 2.65, respectively. Repeated measure of ANOVA revealed that all parameters in the bleaching groups were significantly influenced by time (P < 0.001). Compared with control group, bleaching resulted significant change of ΔTP, Δchroma, Δwhiteness, ΔL(*), Δa(*), Δb(*), ΔE, ΔFI and ΔFI% (P < 0.001). There was no significant difference between three bleaching groups on ΔTP, Δmasking effects, Δchroma, Δwhiteness, ΔL(*), Δb(*), ΔE, ΔFI and ΔFI%. Correlation analysis demonstrated that FI was associated with chroma, a(*), b(*) and whiteness, respectively, and ΔFI was associated with ΔTP, Δmasking effects, Δwhiteness, Δchroma, Δb(*) and ΔE.</p><p><b>CONCLUSIONS</b>30% HP with different pH values could result in the same change of the color, translucency and laser-induced fluorescence of human dentin.Laser-induced fluorescence was associated with dentinal color and translucency, which might be a novel way to investigate the bleaching mechanism of dentin.</p>

Vitrification of oocytes for in vitro fertilization and embryo transfer / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the feasibility, indication and method of oocyte vitrification during the IVF - ET procedure, so as to increase the utilization of oocytes and reduce oocyte waste.</p><p><b>METHODS</b>This study included the patients whose husbands failed to provide sperm samples at the time of oocyte pickup or from whom more than 25 oocytes were obtained. With the patients' consent, some of their oocytes were subjected to cryopreservation by vitrification, and used for IVF - ET after thawed.</p><p><b>RESULTS</b>Totally, 53 oocytes from 7 patients were thawed, and 44 (83.02%) survived, of which 41 M II oocytes were subjected to ICSI and 32 (72.73%) were fertilized. Thirty embryos were formed, with a cleavage rate of 93.75%. Sixteen embryos were transferred in 9 cycles, with achievement of 2 clinical pregnancies and delivery of 3 healthy babies. The implantation rate was 18.75% and the live birth rate 22.22%. Seven of the embryos were still cryopreserved.</p><p><b>CONCLUSION</b>Cryopreservation of oocytes by vitrification effects satisfactory rates of survival and fertilization, and that of surplus oocytes can increase oocyte utilization and adds to the alternatives for IVF - ET.</p>

Breeding of transgenic mice expressing human tau isoform with P301L mutation and identification of homozygous transgenic mice / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To establish homozygous transgenic mouse strain expressing human tau isoform with P301L mutation.</p><p><b>METHODS</b>Five transgenic mice expressing human tau isoform with P301L mutation were obtained by microinjection into male nuclei. Homozygote and hemizygote were identified by PCR and real-time fluorescent quantitative PCR.</p><p><b>RESULTS</b>Ninety five homozygous transgenic mice were selected, and the results indicated that homozygous transgenic mice were superior to hemizygote in simulating the changes of biological characteristics.</p><p><b>CONCLUSION</b>Exogenous gene tau is able to stably transmit to next generation and the combination of SYBR Green real-time fluorescent quantitative PCR with the traditional mating is a fast, reliable and economical way to screen homozygous and hemizygous transgenic mice.</p>

Optimized HPLC-DAD in simultaneous determination of 4 flavonoids in Apocynum venetum / 第二军医大学学报

Objective: To establish an optimized HPLC method for simultaneous determination of rutin, hyperoside, isoquercitrin, and quercetin in Apocynum venetum obtained from different locations. Methods: The separation was performed on a Shiseido C18 (3.0 μm, 30mmX100mm) column by gradient elution with acetonitrile: methanol = 10: 1 as the mobile phase A and 0.1% formic asid as the mobile phase B (0-4 min, 5% → 16%A; 4-15 min, 16% → 23%A; 15-20 min, 23% → 35%A; 20-22 min, 35% → 55%A) at a flow rate of 0.6 ml • min-1. The detection wave length of DAD was set at 360 nm, and the column temperature was 30°C. The injection volume was 5 μl. Results: Rutin, hyperoside, isoquercitrin, and quercetin were separated at base line within 22 min with good linearity (r = 0.9999), with the linearity range being 0.308 4 ~ 30.84 μg • ml-1 (r = 0.9999), 0.877 6-87.76 μg • ml-1 (r=0.9999), 0.9020 ~ 90.20 μg • ml-1(r = 0.9999),and 0.2498 ~ 24.98 μg • ml-1 (r = 0.9999), respectively. The result of intra-day and inter-day precisions, limits of detection and quantitation were all within the normal ranges. The recovery rates (n = 3) were 102.0%, 96.40%, and 103.8% for rutin, 98.50%, 101.0%, and 102.9% for hyperoside, 98.40%, 100.4%, and 101.4% for isoquercitrin, and 104.4%, 103.1%, and 103.5% for quercetin. The contents of the above 4 flavonoids were determined in Apocynum venetum from 9 different locations. Conclusion: The method developed in this study is rapid, simple, accurate, reliable, and with good repeatability; the method provides evidence for the quality control of Apocynum venetum.

MT1-MMP up-regulates VEGF expression in human breast carcinoma MCF-7 cells and induces tumor angiogenesis / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the function of MT1-MMP in tumor angiogenesis and elucidate the possible way of action that MT1-MMP contributes to angiogenesis.</p><p><b>METHODS</b>MT1-MMP was transfected into human breast carcinoma cell line MCF-7 cells. Semi-quantitative RT-PCR and immunofluorescence staining were employed to detect the expression of VEGF in the transfected and non-transfected MCF-7 cells. Tumor growth, microvessel density and expression of VEGF in nude mice were detected through in vivo tumorigenicity assay.</p><p><b>RESULTS</b>In MT1-MMP stable transfected MCF-7 cells, mRNA expression of VEGF(189), VEGF(165), and VEGF(121) and immunofluorescence intensity were significantly elevated (P < 0.001). In vivo tumorigenicity assay in the nude mice showed that MT1-MMP promoted tumor growth. The MVD in the MT1-MMP-transfected cells-transplanted tumor tissue was significantly elevated (P < 0.05). Immunohistochemical assay showed that there was a strong immunostaining of VEGF in those tumor tissues.</p><p><b>CONCLUSION</b>MT1-MMP can induce tumor angiogenesis through up-regulation of VEGF expression. This function of MT1-MMP may open a new approach for clinical anti-tumor research and anti-tumor drug development.</p>

Changes in hyoid bone and tongue positions, and oral cavity volume after mandibular setback by sagittal split ramus osteotomy

Dermoid Cyst on the Floor of the Mouth: A Case Report