Search for η

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2 nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun.

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

Observation and determination of periodontal tissue profile using optical coherence tomography.

BACKGROUND AND OBJECTIVE: Diagnosis is a crucial step in periodontal treatment. The aim of this study was to evaluate the effectiveness of optical coherence tomography (OCT) for observation and determination of periodontal tissue profiles in vivo. MATERIAL AND METHODS: In experiment 1, refractive indices of purified water, porcine gingiva and human gingiva at 1330 nm were determined for the analysis of OCT images of periodontal tissues. In experiment 2, OCT examination was performed in the midlabial apico-coronal plane of mandibular anteriors in 30 Asian volunteers with healthy gingiva. Sulcus depth was measured on intra-oral photographs taken during probing. In the OCT images, the gingival, epithelial and connective tissue thickness, and the position of alveolar bone crest were determined and finally, the biologic width was measured. RESULTS: Refractive indices of purified water, porcine gingiva and human gingiva were 1.335, 1.393 and 1.397, respectively. Cross-sectional images of gingival epithelium, connective tissue and alveolar bone were depicted in real-time. The sulcular and junctional epithelium could be visualized occasionally. Laser penetration and reflection were limited to a certain depth with an approximate maximal imaging depth capability of 1.5 mm and OCT images of the periodontal structure were not clear in some cases. The average maximal thickness of gingiva and epithelium and biologic width at the mandibular anteriors were 1.06 ± 0.21, 0.49 ± 0.15 and 2.09 ± 0.60 mm, respectively. CONCLUSION: OCT has promise for non-invasive observation of the periodontal tissue profile in detail and measurement of internal periodontal structures including biologic width in the anterior region.

Increased systemic levels of inflammatory mediators following one-stage full-mouth scaling and root planing.

BACKGROUND AND OBJECTIVE: Full-mouth scaling and root planing (FM-SRP) acts as a potent inflammatory stimulus immediately after treatment; however, systemic inflammation typically improves in the long term. The contribution of FM-SRP to systemic biological and acute-phase responses is largely unknown. The purpose of this prospective intervention study was to assess the systemic and local biological responses after FM-SRP. MATERIAL AND METHODS: Thirty-one patients with generalized moderate-to-severe chronic periodontitis received 1-stage FM-SRP. Measurement of clinical parameters and body temperature as well as collection of subgingival plaque, peripheral blood and gingival crevicular fluid was performed before and after treatment 2 or 3 times. Quantification of periodontopathic bacteria in the sulcus and measurement of corresponding serum IgG titers were performed. Systemic and local inflammatory markers such as endotoxin, high-sensitive C-reactive protein (hs-CRP) and 6 inflammatory cytokines were assessed using high-sensitivity assays. RESULTS: Compared to baseline values, FM-SRP resulted in a substantial improvement in clinical parameters (P < .05), lower bacterial counts (P < .01) and a significant decrease of IgG titers against Porphyromonas gingivalis (P < .001) 6 weeks after treatment. Comparing baseline parameters to those at 1 day post-treatment, there was a statistically significant elevation in body temperature (P = .007). In addition, a 5-fold increase in hs-CRP (P < .001), a remarkable increase in interferon-γ (P < .001) and a slight increase in interleukin (IL)-12p70 (P = .001) were detected in serum samples. In the gingival crevicular fluid, marked increases in hs-CRP (P < .001), IL-5 (P = .001), IL-6, IL-12p70 and tumor necrosis factor-α (P < .001 for the latter 3 markers) were noted 1 day after treatment. Endotoxin levels were below measurable limits for most time points. CONCLUSION: FM-SRP resulted in clinical and microbiological improvement 6 weeks post-treatment, but produced a moderate systemic acute-phase response including elevated inflammatory mediators 1 day post-treatment.

Time-Reversal Measurement of the p-Wave Cross Sections of the

The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

Energy Spectrum of Cosmic-Ray Electron and Positron from 10 GeV to 3 TeV Observed with the Calorimetric Electron Telescope on the International Space Station.

First results of a cosmic-ray electron and positron spectrum from 10 GeV to 3 TeV is presented based upon observations with the CALET instrument on the International Space Station starting in October, 2015. Nearly a half million electron and positron events are included in the analysis. CALET is an all-calorimetric instrument with total vertical thickness of 30 X_{0} and a fine imaging capability designed to achieve a large proton rejection and excellent energy resolution well into the TeV energy region. The observed energy spectrum over 30 GeV can be fit with a single power law with a spectral index of -3.152±0.016 (stat+syst). Possible structure observed above 100 GeV requires further investigation with increased statistics and refined data analysis.

Levobupivacaine-dextran mixture for transversus abdominis plane block and rectus sheath block in patients undergoing laparoscopic colectomy: a randomised controlled trial.

We performed a randomised controlled double-blinded study of patients having laparoscopic colectomy with bilateral transversus abdominis plane block plus rectus sheath block, comparing a control group receiving 80 ml levobupivacaine 0.2% in saline with a dextran group receiving 80 ml levobupivacaine 0.2% in 8% low-molecular weight dextran. Twenty-seven patients were studied in each group. The mean (SD) maximum plasma concentration of levobupivacaine in the control group (1410 (322) ng.ml(-1) ) was higher than the dextran group (1141 (287) ng.ml(-1) ; p = 0.004), and was reached more quickly (50.6 (30.2) min vs 73.2 (24.6) min; p = 0.006). The area under the plasma concentration-time curve from 0 min to 240 min in the control group (229,124 (87,254) ng.min.ml(-1) ) was larger than in the dextran group (172,484 (50,502) ng.min.ml(-1) ; p = 0.007). The median (IQR [range]) of the summated numerical pain rating score at rest during the first postoperative 24 h in the control group (16 (9-20 [3-31]) was higher than in the dextran group (8 (2-11 [0-18]); p = 0.0001). In this study, adding dextran to levobupivacaine decreased the risk of levobupivacaine toxicity while providing better analgesia.

All-atom molecular dynamics calculation study of entire poliovirus empty capsids in solution.

Small viruses that belong, for example, to the Picornaviridae, such as poliovirus and foot-and-mouth disease virus, consist simply of capsid proteins and a single-stranded RNA (ssRNA) genome. The capsids are quite stable in solution to protect the genome from the environment. Here, based on long-time and large-scale 6.5 × 10(6) all-atom molecular dynamics calculations for the Mahoney strain of poliovirus, we show microscopic properties of the viral capsids at a molecular level. First, we found equilibrium rapid exchange of water molecules across the capsid. The exchange rate is so high that all water molecules inside the capsid (about 200,000) can leave the capsid and be replaced by water molecules from the outside in about 25 µs. This explains the capsid's tolerance to high pressures and deactivation by exsiccation. In contrast, the capsid did not exchange ions, at least within the present simulation time of 200 ns. This implies that the capsid can function, in principle, as a semipermeable membrane. We also found that, similar to the xylem of trees, the pressure of the solution inside the capsid without the genome was negative. This is caused by coulombic interaction of the solution inside the capsid with the capsid excess charges. The negative pressure may be compensated by positive osmotic pressure by the solution-soluble ssRNA and the counter ions introduced into it.

Probe of the solar magnetic field using the "cosmic-ray shadow" of the sun.

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

Flexural Properties and Polished Surface Characteristics of a Structural Colored Resin Composite.

OBJECTIVE: The aim of this study was to determine the flexural properties and surface characteristics of a structural colored resin composite after different finishing and polishing methods, in comparison to those of conventional resin composites. METHODS AND MATERIALS: A structural color resin composite, Omnichroma (OM, Tokuyama Corp, Chiyoda City, Tokyo, Japan), and two comparison resin composites, Filtek Supreme Ultra (FS, 3M, St Paul, MN, USA) and Tetric EvoCeram (TE, Ivoclar Vivadent, Schaan, Liechtenstein), were used. The flexural properties of the resin composites were determined in accordance with the ISO 4049 specifications. For surface properties, 70 polymerized specimens of each resin composite were prepared and divided into seven groups of 10. Surface roughness (Sa), gloss (GU), and surface free energy (SFE) were investigated after the following finishing and polishing methods. Three groups of specimens were finished with a superfine-grit diamond bur (SFD), and three with a tungsten carbide bur (TCB). After finishing, one of the two remaining groups was polished with a one-step silicone point (CMP), and the other with an aluminum oxide flexible disk (SSD). A group ground with SiC 320-grit was set as a baseline. RESULTS: The average flexural strength ranged from 116.6 to 142.3 MPa in the following order with significant differences between each value: FS > TE > OM. The average E ranged from 6.8 to 13.2 GPa in the following order with significant differences between each value: FS > TE > OM. The average R ranged from 0.77 to 1.01 MJ/mm3 in the following order: OM > FS > TE. The Sa values of the OM groups polished with CMP and SSD were found to be significantly lower than those of the other resin composites, regardless of the finishing method. The GU values appeared to be dependent on the material and the finishing method used. The OM specimens polished with SSD showed significantly higher GU values than those polished with CMP. Most of the resin composites polished with SSD demonstrated significantly higher γS values compared to the other groups. Extremely strong negative correlations between Sa and GU in the combined data from the three resin composites and each resin composite and between Sa and γS in the OM specimens were observed; GU showed a strong positive correlation with γS in the same material. CONCLUSION: These findings indicate that both flexural and surface properties are material dependent. Furthermore, the different finishing and polishing methods used in this study were observed to affect the Sa, GU, and SFE of the resin composites.

Histological evaluation of alveolar ridge augmentation using injectable calcium phosphate bone cement in dogs.

Alveolar ridge augmentation is an important procedure to restore tooth loss. Several types of graft materials have been used for augmenting the alveolar ridge. An injectable calcium phosphate cement (CPC) has been applied to periodontal bone defects and has shown favourable results. Thus, this CPC may work as an effective graft material for alveolar ridge augmentation. The aim of this study was to evaluate the effectiveness of the CPC for large-scaled (about 7 x 8 x 6 mm) ridge augmentation in dogs. Alveolar ridge defects were created bilaterally in the maxilla of six beagle dogs. The CPC was applied to one of the bilateral maxillary defects. The untreated defect on the contralateral side served as control. The animals were sacrificed at 6 months after surgery and decalcified histological specimens of the alveolar ridge were prepared histometrically and evaluated under a light microscope. Newly formed and reconstructed alveolar ridges covering the CPC were observed in all experimental sites. In the control sites, only slight newly bone formation was observed. Histomorphometrical analysis indicated that the CPC grafted group exhibited significantly (P = 0.0001) increased area and height in new bone formation compared with those of the control group. The results indicate that the CPC appears to be an effective material for alveolar ridge augmentation and may act as a space maintainer to conduct new bone formation.

Essential roles of ERK-mediated phosphorylation of vinexin in cell spreading, migration and anchorage-independent growth.

Vinexin is an adaptor protein supposed to play pivotal roles in various cellular events such as cell adhesion, cytoskeletal organization, signaling and gene expression. Despite the possible importance, physiological functions and regulatory mechanisms of vinexin are largely unknown. In addition, although vinexin was reported to be phosphorylated by extracellular signal-regulated kinase (ERK), physiological significance of the phosphorylation remains to be elucidated. Here we carried out characterization of endogenous vinexin and found that it was enriched at the leading edge of migrating cells and focal adhesions of spread cells. In the analyses using ERK-phosphorylated vinexin-specific antibody, the phosphorylation signal was also detected at the leading edges of migrating cells and at cell periphery of spreading cells, whereas only faint signal was observed at focal adhesions of well-spread cells. We then established LNCaP cell lines stably expressing GFP-fused vinexinbeta or two mutants at Ser189 that mimic the ERK-phosphorylated or -unphosphorylated vinexin beta. Based on the analyses using the lines, the phosphorylation was likely to inhibit the cell spreading and migration. On the other hand, anchorage-independent cell growth was inhibited by unphosphorylated vinexinbeta. Taken together, ERK-mediated phosphorylation of vinexinbeta is strongly suggested to occur in a spatio-temporally regulated manner and play important roles in cell spreading, migration and anchorage-independent growth.

Synthesis of pyrophosphate-containing compounds that stimulate Vgamma2Vdelta2 T cells: application to cancer immunotherapy.

Human Vgamma2Vdelta2 T cells recognize nonpeptide antigens, such as isoprenoid pyrophosphomonoester intermediates, alkylamine compounds, and bisphosphonate drugs, as well as some tumor cells. Although attempts have been made to derive novel cancer immunotherapies based on the discovery of these unconventional antigens, effective therapies remain to be developed. Here, we synthesized a series of pyrophosphate-containing compounds and examined the chemical requirements for the recognition of pyrophosphomonoester antigens by gammadelta T cells. The structural analysis clearly demonstrated that a proximal methylene moiety plays a crucial role in the stimulatory activity of the antigens. For optimal gammadelta T cell proliferation, we find that the use of human serum albumin was preferred and that pyrophosphomonoesters were superior to nitrogen-containing bisphosphonate compounds. Using these techniques, we have successfully expanded gammadelta T cells from healthy donors as well as from cancer patients using one of the most active compounds, 2-methyl-3-butenyl-1-pyrophosphate (2M3B1PP). The resulting expanded gammadelta T cells exhibited potent, cytotoxic activity against a wide variety of tumor cell lines. Even gammadelta T cells from a patient with advanced liver carcinoma efficiently responded to 2M3B1PP and exhibited strong cytotoxic activity against tumor cells. The pretreatment of tumor cells with nonpeptide antigens was essential for efficient cytotoxicity via TCR-gammadelta. The present study suggests a novel strategy for cancer immunotherapy using synthetic small pyrophosphate-containing compounds and nitrogen-containing bisphosphonates.

Association of emergence of HLA antibody and acute rejection in intestinal transplant recipients: a possible evidence of acute humoral sensitization.

Development of HLA antibody has been associated with chronic allograft failure in kidney recipients. We tested HLA antibody in posttransplant sera of intestinal recipients: 126 sera from 28 pediatric recipients were tested for HLA antibody by flow PRA (f-PRA). Median age was 1.1 years (0.44-17). Graft types included isolated intestine (n = 6), liver and intestine (n = 3), modified multivisceral (n = 3), and multivisceral grafts (n = 16). Greater than 10% of either class I (CI) or class II (CII) f-PRA was considered positive, and >30% strongly positive. Five of 28 patients had positive f-PRA in multiple samples; the remaining 23 had either no positive or only one positive sample. Three patients had strongly positive f-PRA. Patients with multiple positive samples were recipients of two modified multivisceral and three multivisceral grafts. Only one of these patients had a positive PRA pretransplant. Cytotoxic cross-match at transplant was negative for all. The three with strongly positive f-PRA showed significant episodes of rejection around the time of positive samples. One of them who persistently had f-PRA value >80% (from day 13-113) died of refractory rejection. The other two had f-PRA of 76% and 53% during the early postoperative course with associated episodes of rejection. F-PRA value decreased with rejection therapy. Only one of the 23 patients (4%) with negative f-PRA had an episode of rejection around the time of sample collection. Development of HLA antibody after intestinal transplantation seems to have significant association with acute rejection episodes.

Fluorescent substances in mouse and human sera as a parameter of in vivo lipid peroxidation.

Water-soluble fluorescent substances like lipofuscin were found in the protein fraction of mouse and human sera and had fluorescence characteristics with excitation and emission maxima at 335-340 and 435-440 nm for mice, and at 355-360 and 430-435 nm for human, respectively. When oxidized [U-14 C]linoleic acid was given intraperitoneally to mice, or added to the serum in vitro, both the fluorescence intensity and radioactivity of serum protein increased dose-dependently in the two tests. Also, the fluorescent substances responded well to acceleration of in vivo lipid peroxidation caused by carbon tetrachloride. These results indicate that the substances were some binding compounds between the degraded lipids and serum proteins, and that they could be taken as a parameter of in vivo lipid peroxidation. The distribution of the pigments in the serum proteins, albumin and globulins, was shown to depend upon the number of free amino groups in each protein which appear to be binding sites of degraded lipids. Spectral characteristics and some chemical properties of the substances suggest that they might not be conjugated Schiff bases formed from protein and malondialdehyde but might be due to some other stable compounds. Significantly high levels of the substances were observed in sera of patients with diabetes and hypertension.

Domain closure mechanism in transferrins: new viewpoints about the hinge structure and motion as deduced from high resolution crystal structures of ovotransferrin N-lobe.

The crystal structure of holo hen ovotransferrin N-lobe refined at 1.65 A resolution has been obtained. The final model gave an R-factor of 0.173 in the resolution range between 10.0 and 1.65 A. The comparison of the structure with previous high-resolution apo and Fe(3+)-loaded, domain-opened intermediate structures provides new viewpoints on the domain closure mechanism upon Fe(3+) uptake in ovotransferrin N-lobe. Overall, conformational transition follows the common mechanism that has been first demonstrated for lactoferrin N-lobe; the domains 1 and 2 rotate 49.7 degrees as rigid bodies with a translation of 2.1 A around a screw-axis that passes through the two interdomain beta-strands (89-94 and 244-249). It is generally believed that the two strands display a hinge-like motion. Here, the latter strand indeed displays an ideal hinge nature: the segments 244-246 and 248-249 behave as a part of the rigid body of domain 2 and that of domain 1, respectively, and a sharp bend upon the domain closure is largely accounted for by the changes in the torsion angles phi and psi of Val247. We find, however, that the mode of the conformational change in the first beta-strand is much more complex. Two of the five inter beta-strand hydrogen bonds undergo crucial exchanges: from Ser91-N...Val247-O and Thr89-O...Ala249-N in the open apo and intermediate structures into Tyr92-N...Val247-O and Thr90-O...Ala249-N in the closed holo structure. These exchanges, which may be triggered in the intermediate state by modulation in the topological relation between the Fe(3+)-ligated hinge residue Tyr92-OH and the anion anchor residues of helix 5, are accompanied by a large conformational change and extensive hydrogen bonding rearrangements in a long stretch of segment of Glu82 to Tyr92. Such structural transition would work as a driving force for the domain closure, which highlights a "door closer"-like role, in addition to the canonical-hinge role, for the interdomain polypeptide segment pair. As an alternative hinge that secures the correct domain motion by being placed on a significant distance from the beta-strand hinge, we point out the participation of the van der Waals contacts formed between domain 1 residue of Met331 and domain 2 residues of Trp125, Ile129 and Trp140.

Comprehensive gene expression profiling of anaplastic thyroid cancers with cDNA microarray of 25 344 genes.

Little is known about the genetic mechanisms of anaplastic thyroid cancer (ATC). This is the most virulent of all human malignancies, and it is believed to result from transformation of differentiated thyroid cancers. To identify a set of genes involved in the development of ATC, we investigated expression profiles of 11 cell lines derived from ATC using a cDNA microarray representing 25 344 genes. Semi-quantitative RT-PCR experiments carried out for some genes that had shown altered expression on the microarray verified frequent over-expression of destrin, HSPA8, stathmin, LDH-A, ATP5A1, PSMB6, B23, HDP-1 and LDH-B, and frequent under-expression of thyroglobulin, PBP and c-FES/FPS genes among the cell lines and also among ten primary ATCs. In addition to mRNA expression studies, up-regulation of GDI2, destrin and stathmin were confirmed with immunohistochemical analysis. The extensive list of genes identified provides valuable information towards understanding the development of ATC, and provides a source of possible biomarkers for diagnosis and/or molecular targets for the development of novel drugs to treat ATC.

Propofol decreases the clearance of midazolam by inhibiting CYP3A4: an in vivo and in vitro study.

OBJECTIVE: To examine the effect of propofol on the pharmacokinetics of midazolam in vivo and to elucidate the mechanism of the pharmacokinetic changes of midazolam by propofol with the use of human liver microsomes and recombinant CYP3A4. METHODS: In an in vivo, double-blind randomized study, 24 patients received 0.2 mg/kg midazolam and either 2 mg/kg propofol (propofol group) or placebo (placebo group) for induction of anesthesia. In the propofol group, continuous infusion of propofol at 9 mg/kg/h was started immediately after the bolus infusion of propofol and was maintained for an hour. In the placebo group the same dose of soybean emulsion as a placebo was given and infused intravenously for an hour instead of propofol. In an in vitro study the effect of propofol on the metabolism of midazolam was studied with human liver microsomes and recombinant CYP3A4. RESULTS: In the propofol group the mean clearance of midazolam was decreased by 37% (P = .005) and the mean elimination half-life was prolonged by 61% (P = .04) compared with the placebo group. The mean plasma concentrations of 1'-hydroxymidazolam were lower in the propofol group than in the placebo group at 5, 10, 15, 20, and 30 minutes after midazolam was administered (P < .05). The mean (+/-SD) Michaelis-Menten constant for midazolam 1'-hydroxylation by human liver microsomes was 5.6 +/- 3.3 micromol/L. The formation of 1'-hydroxymidazolam was competitively inhibited by propofol, and the mean inhibition constant was 56.7 +/- 16.6 micromol/L. The mean Michaelis-Menten constant and mean inhibition constant values for midazolam 1'-hydroxylation by recombinant CYP3A4 were 4.0 micromol/L and 61.0 micromol/L, respectively, consistent with the mean values obtained from human liver microsomes. CONCLUSION: Propofol decreases the clearance of midazolam, and the possible mechanism is the competitive inhibition of hepatic CYP3A4.

Development of lentiviral vectors for antiangiogenic gene delivery.

Growth and metastasis of malignant tumors requires angiogenesis. Inhibition of tumor-induced angiogenesis may represent an effective cytostatic strategy. We have constructed recombinant self-inactivating lentiviral vectors expressing angiostatin and endostatin, and have tested their antiangiogenic activities. As VSV-G-pseudotyped lentiviral vectors showed low relative transduction titers on bovine aortic and human umbilical vein endothelial cells, it was difficult to achieve significant inhibition of endothelial cell growth by lentivirus-mediated antiangiogenic gene transfer directly to endothelial cells without concomitant vector-associated cytotoxicity. However, lentivirus vectors could efficiently and stably transduce T24 human bladder cancer cells that are relatively resistant to adenovirus infection due to loss of coxsackievirus-adenovirus receptor expression. Long-term expression and secretion of angiostatin and endostatin from lentivirus-transduced T24 cells resulted in significant inhibition of cellular proliferation on coculture with endothelial cells. This report represents the first use of lentivirus-based vectors to deliver the antiangiogenic factors, angiostatin and endostatin, and suggests the potential utility of antiangiogenic gene therapy with lentiviral vectors for the treatment of cancer.

Phytoestrogens attenuate oxidative DNA damage in vascular smooth muscle cells from stroke-prone spontaneously hypertensive rats.

OBJECTIVES: A recent study demonstrated that reactive oxygen species (ROS) were involved in the maintenance of hypertension in stroke-prone spontaneously hypertensive rats (SHRSP). However, the role of oxidative stress in hypertension and its related diseases in SHRSP remains unknown. To determine whether phytoestrogens attenuate oxidative DNA damage in vascular smooth muscle cells (VSMC) from SHRSP and Wistar-Kyoto (WKY) rats, we investigated the effect of daidzein, genistein and resveratrol on oxidative DNA damage in VSMC, induced by advanced glycation end-products (AGEs). METHODS: VSMC were treated with AGEs in the presence or absence of phytoestrogens for the indicated time. Cellular degeneration induced by AGEs was characterized in terms of intracellular oxidant levels, intracellular total glutathione (GSH) levels, mRNA expression for gamma-glutamylcysteine synthetase (GCS), and a new marker of oxidative stress, 8-hydroxy-2'-deoxyguanosine (8-OHdG) contents. RESULTS: AGEs stimulated 8-OHdG formation in VSMC in a time- and dose-dependent manner. We also confirmed that VSMC from SHRSP were more vulnerable to oxidative stress induced by AGEs, than VSMC from WKY rats. Daidzein, genistein or resveratrol reduced AGEs-induced 8-OHdG formation in a dose-dependent manner. The preventive effects of phytoestrogens on 8-OHdG formation remarkably paralleled changes in the intracellular oxidant levels in VSMC following AGEs treatment. We further demonstrated that phytoestrogens increase intracellular total GSH level in VSMC. Increased GSH synthesis was due to enhanced expression of the rate-limiting enzyme for GSH synthesis, GCS. Phytoestrogens-stimulated total GSH level in VSMC could lead to decreased intracellular oxidant levels, and thus prevent oxidative DNA damage, induced by AGEs. The phytoestrogens are powerful antioxidants able to interfere with AGEs-mediated oxidative DNA damage of VSMC, and are potentially useful against vascular diseases where ROS are involved in hypertension.