ABSTRACT Solvent extraction of molybdenum and tungsten as homologues of Sg with α‐benzoinoxime from HCl solutions has been investigated. The extraction equilibration was achieved at 20s for Mo and W. Molybdenum was almost quantitatively... more
ABSTRACT Solvent extraction of molybdenum and tungsten as homologues of Sg with α‐benzoinoxime from HCl solutions has been investigated. The extraction equilibration was achieved at 20s for Mo and W. Molybdenum was almost quantitatively extracted from 0.001 to 4 M HCl solutions, and the extraction yields decreased at higher and lower acid concentrations due to the formation of anionic oxychloride complex and anionic species MO4 2−, respectively. The extraction yield of W was lower than that of Mo during the whole range of acid concentration. The composition of the extracted species was determined by using the slope method in present experiment. The elemental analysis, IR and 1H NMR spectra of the extracted species suggest that the extracted complex contain one MoO2 2+ or WO2 2+ groups bonded with two α‐benzoinoxime molecules.
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Astrocytes and microglia, the two immune-regulatory cells of the central nervous system (CNS), are activated by a variety of pathogens and cytokines to elicit rapid transcriptional responses. This program of activation is initiated by a... more
Astrocytes and microglia, the two immune-regulatory cells of the central nervous system (CNS), are activated by a variety of pathogens and cytokines to elicit rapid transcriptional responses. This program of activation is initiated by a set of intracellular signaling cascades that includes mitogen-activated protein kinase (MAPK), nuclear factor (NF) kappaB, and Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathways. This study defines the critical role that NADPH oxidase(Phox)-derived reactive oxygen species (ROS) play in lipopolysaccharide (LPS)- and interferon (IFN)gamma-induced signaling cascades leading to gene expression in glial cells. Treatment of rat microglia and astrocytes with LPS and IFNgamma resulted in a rapid activation of Phox and the release of ROS followed by an induction of inducible nitric oxide synthase (iNOS) expression. iNOS induction was blocked by inhibitors of Phox, i.e., diphenylene iodonium chloride (DPI) and 4-(2-aminoethyl) benzenesulfonylfluoride (AEBSF), suggesting an involvement of ROS signaling in iNOS gene expression. Exogenous catalase but not superoxide dismutase suppressed the basal activity and completely blocked induced levels of NO/iNOS, suggesting that hydrogen peroxide is the ROS involved. Phox inhibitors and catalase also suppressed LPS/IFNgamma-induced expression of cytokines, i.e., interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)alpha and blocked LPS activation of MAP kinases (i.e., p38 MAPK, c-Jun N-terminal kinase and extracellular signal-regulated kinase), NFkappaB, and IFNgamma-induced STAT1 phosphorylation. A microglial cell line stably transfected with a mutant form of Phox subunit, i.e., p47(phox) W(193)R, and primary astrocytes derived from Phox-deficient mice showed attenuated ROS production and induction of iNOS in response to LPS/IFNgamma, further strengthening the notion that Phox-derived ROS are crucial for proinflammatory gene expression in glial cells.
Research Interests: Neuroscience, Psychology, Cytokines, Enzyme Inhibitors, Oxidative Stress, and 18 moreLipopolysaccharide, Reactive Oxygen Species, Mice, Animals, Microglia, NF-kappa B, Astrocytes, NADPH oxidase, Lipopolysaccharides, Rats, Nitric Oxide Synthase, Redox Regulation, Encephalitis, Neurosciences, Oxidation-Reduction, Interferon gamma, Gliosis, and Inflammatory response
Neuropilin-1 (NRP-1), a recently identified co-receptor for vascular endothelial growth factor, is expressed by several nongastrointestinal tumor types and enhances prostate cancer angiogenesis and growth in preclinical models. We... more
Neuropilin-1 (NRP-1), a recently identified co-receptor for vascular endothelial growth factor, is expressed by several nongastrointestinal tumor types and enhances prostate cancer angiogenesis and growth in preclinical models. We investigated the expression and regulation of NRP-1 and the effect of NRP-1 overexpression on angiogenesis and growth of human colon adenocarcinoma by immunohistochemistry and in situ hybridization. NRP-1 was expressed in 20 of 20 human colon adenocarcinoma specimens but not in the adjacent nonmalignant colonic mucosa. By reverse transcriptase-polymerase chain reaction analysis, NRP-1 mRNA was expressed in seven of seven colon adenocarcinoma cell lines. Subcutaneous xenografts of stably transfected KM12SM/LM2 human colon cancer cells overexpressing NRP-1 led to increased tumor growth and angiogenesis in nude mice. In in vitro assays, conditioned medium from NRP-1-transfected cell lines led to an increase in endothelial cell migration, but did not affect endothelial cell growth. Epidermal growth factor (EGF) led to induction of NRP-1 in human colon adenocarcinoma cells and selective blockade of the epidermal growth factor receptor (EGFR) decreased constitutive and EGF-induced NRP-1 expression. Blockade of the Erk 1/2 and P38 mitogen-activated protein kinase signaling pathways also led to a decrease in constitutive and EGF-induced NRP-1 expression. These findings demonstrate the ubiquitous expression of NRP-1 in human colon cancer and suggest that NRP-1 may contribute to colon cancer angiogenesis and growth. This study also suggests that EGF and mitogen-activated protein kinase signaling pathways play an important role in NRP-1 regulation in colon cancer cells.
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Neuropilin-1 (NRP-1) is a co-receptor for vascular endothelial growth factor (VEGF). During neovascularization, vascular smooth muscle cells (VSMCs) and pericytes modulate the function of endothelial cells. Factors that mediate NRP-1 in... more
Neuropilin-1 (NRP-1) is a co-receptor for vascular endothelial growth factor (VEGF). During neovascularization, vascular smooth muscle cells (VSMCs) and pericytes modulate the function of endothelial cells. Factors that mediate NRP-1 in human VSMCs (hVSMCs) remain to be elucidated. We studied various angiogenic cytokines to identify factors that increase NRP-1 expression in hVSMCs. Treatment of hVSMCs with basic fibroblast growth factor (b-FGF) induced expressions of NRP-1 mRNA and protein whereas epidermal growth factor, insulin-like growth factor-1, and interleukin-1beta did not. b-FGF induced phosphorylation of Erk-1/2 and JNK. MEK1/2 and nuclear factor kappa B (NF-kappaB) inhibitors (U0126 and TLCK, respectively) blocked the ability of b-FGF to induce NRP-1 mRNA expression, but inhibition of JNK (SP600125) or PI3-kinase activity (wortmannin) did not. Further, the increase in NRP-1 expression by b-FGF enhanced hVSMCs migration in response to VEGF(165). This effect was dependent on the binding of VEGF(165) to VEGFR-2, as blocking antibodies to VEGFR-2, but not VEGFR-1, inhibited VEGF(165)-induced migration. In conclusion, b-FGF increased NRP-1 expression in hVSMCs that in turn enhance the effect of VEGF(165) on cell migration. The enhanced migration of hVSMCs was mediated through binding of VEGF(165) to both NRP-1 and VEGFR-2, as inhibition of VEGFR-2 on these cells blocked the effect of VEGF-mediated cell migration.
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Angiopoietin (Ang)-1 is an important regulator of endothelial cell (EC) survival and stabilization. Ang-1 exerts its biological effects by binding to the EC-specific tyrosine kinase receptor Tie-2, and initiates intracellular signaling in... more
Angiopoietin (Ang)-1 is an important regulator of endothelial cell (EC) survival and stabilization. Ang-1 exerts its biological effects by binding to the EC-specific tyrosine kinase receptor Tie-2, and initiates intracellular signaling in ECs. However, regulatory mechanisms for endothelial Ang-1 expression have not been completely elucidated. In this study, we investigated the effects of angiogenic cytokines and growth factors on Ang-1 expression in human umbilical vein ECs (HUVECs). Northern blot analysis was performed after HUVECs were exposed to interleukin-1beta (IL-1beta), tumor necrosis factor-alpha, platelet-derived growth factor-BB, insulin-like growth factor-1, or vascular endothelial growth factor (VEGF). Both IL-1beta and tumor necrosis factor-alpha caused marked down-regulation of Ang-1 mRNA levels at 4 h with a further decrease observed at 24 h. Using signaling inhibitors, we identified the P38 pathway as the pathway that mediates IL-1beta down-regulation of Ang-1. Furthermore, treatment of cells with IL-1beta indirectly (via down-regulation of Ang-1) led to a decrease in Tie-2 autophosphorylation levels in HUVECs. We previously demonstrated that IL-1beta regulates VEGF expression in tumor cells. This observation was confirmed in ECs in the present study. Because pericytes play a role in regulating EC function, we also determined whether IL-1beta would also down-regulate Ang-1 in human vascular smooth muscle cells. Similar to our findings in HUVECs, we found that IL-1beta decreased Ang-1 expression in human vascular smooth muscle cells. Direct effects of IL-1beta on angiogenesis were investigated by use of an in vivo Gelfoam angiogenesis assay in which IL-1beta produced a significant increase in vessel counts (P = 0.0189). These results suggest that IL-1beta indirectly regulates angiogenesis by modulating the expression of Ang-1. IL-1beta may trigger a proangiogenic response by decreasing Ang-1 levels in ECs and pericytes and up-regulating VEGF in ECs and tumor cells.
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The mechanisms responsible for the viscoelasticity and self-healing ability of VHB 4910 are studied. The type of chemical bonds is confirmed using Fourier transform infrared and Raman spectroscopy. The tensile tests demonstrate that the... more
The mechanisms responsible for the viscoelasticity and self-healing ability of VHB 4910 are studied. The type of chemical bonds is confirmed using Fourier transform infrared and Raman spectroscopy. The tensile tests demonstrate that the material has viscoelastic behavior that depends on the deformation speed and changes in the hysteresis area with different tensile strains. The shear modulus of entangled networks increases with the deformation speed. This behavior confirms that the viscoelasticity is due to the dissociation and re-association of non-covalent bonding. The hydrogen bonding initiates the healing process and the diffusion of molecular chains strengthens the self-healing ability.The mechanisms responsible for the viscoelasticity and self-healing ability of VHB 4910 are studied. The type of chemical bonds is confirmed using Fourier transform infrared and Raman spectroscopy. The tensile tests demonstrate that the material has viscoelastic behavior that depends on the deformation speed and changes in the hysteresis area with different tensile strains. The shear modulus of entangled networks increases with the deformation speed. This behavior confirms that the viscoelasticity is due to the dissociation and re-association of non-covalent bonding. The hydrogen bonding initiates the healing process and the diffusion of molecular chains strengthens the self-healing ability.
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Research Interests: Cardiovascular disease, Molecular Mechanics, Signal Transduction, Renin Angiotensin Aldosterone System, Nitric oxide, and 20 moreAnimals, Male, Heart, European, mRna expression levels, Rats, Nitric Oxide Synthase, Time Dependent, Rat, Stilbenes, Cell Proliferation, Lactate dehydrogenase, Angiotensin II, Human Fibroblasts, Intracellular Space, Methyl Ester, Brain Natriuretic Peptide, cyclic GMP, Cell Size, and Atrial Natriuretic Factor
We report a method of obtaining controllable spatially varying liquid crystal pretilt angles using a stacked alignment layer. The stacked alignment layer consists of nano-domains of horizontal and vertical alignment materials. The pretilt... more
We report a method of obtaining controllable spatially varying liquid crystal pretilt angles using a stacked alignment layer. The stacked alignment layer consists of nano-domains of horizontal and vertical alignment materials. The pretilt angle is controlled by varying the domain ratio of the two layers. By using photoalignment material as the top layer, the pretilt angle can be controlled by varying the UV light dosage. A spatially variable UV light beam can be used to control the pretilt angle spatially. An electrically tunable-focus liquid crystal lens is obtained using this method.
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ABSTRACT
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Research Interests: Twins, Pregnancy, Humans, Placenta, Female, and 6 moreMale, Clinical Sciences, Newborn Infant, Adult, Cesarean Section, and Fetus
Vascular endothelial growth factor (VEGF), a dominant angiogenic factor in gastric cancer, is upregulated by cytokines in the tumor microenvironment. Interleukin-1β (IL-1β), a proinflammatory cytokine, has been shown to be proangiogenic... more
Vascular endothelial growth factor (VEGF), a dominant angiogenic factor in gastric cancer, is upregulated by cytokines in the tumor microenvironment. Interleukin-1β (IL-1β), a proinflammatory cytokine, has been shown to be proangiogenic in vivo, despite its not demonstrating angiogenic activity in vitro. We hypothesized that IL-1β regulates VEGF expression in human gastric cancer cells and investigated the mechanism by which this occurs.We treated the TMK-1 human gastric cancer cell line with IL-1β for 1 to 24 hours, and then analyzed VEGF mRNA expression by Northern blotting and signaling intermediates by Western blotting. Signaling inhibitors were used to identify the dominant pathways involved in IL-1β induction of VEGF. VEGF promoter–luciferase constructs and transcription blockers were used to investigate the transcriptional regulation of VEGF by IL-1β.Treating TMK-1 cells with IL-1β increased VEGF mRNA levels and activated extracellular signal-regulated kinases 1 and 2 (Erk 1/2) and p38, but not Akt. Inhibitors of the Erk and p38 pathways blocked IL-1β induction of VEGF mRNA. Treating TMK-1 cells with IL-1β also increased VEGF promoter activity. VEGF transcriptional activity was found to depend on a 120-bp region just proximal to the transcription start site.In human gastric cancer cells, IL-1β induced VEGF through Erk- and p38-dependent pathways; this induction of VEGF was transcriptionally regulated.
Research Interests: Surgery, Cancer, Biological Chemistry, Biophysical Chemistry, Transcription Factors, and 25 moreSignal Transduction, Molecular Biology Cancer, Environmental Sciences, Humans, Kidney, Nitric oxide, Animals, Clinical, Thorax, Biological, Clinical Sciences, Histones, Histone acetyltransferases, Tumor Suppressor Gene, Acetylation, Circulation, Transfection, Base Sequence, Protein Binding, DNA binding proteins, cyclic GMP, Biochemistry and cell biology, Gene Expression Regulation, Vascular Endothelial Growth Factor, and Interleukin
To use distinctive water-medicine cup therapy for treatment of cervical spondylopathy of cervical type as a sample to provide a more effective cupping method for clinic. One hundred and forty cases were randomly divided into a medicine... more
To use distinctive water-medicine cup therapy for treatment of cervical spondylopathy of cervical type as a sample to provide a more effective cupping method for clinic. One hundred and forty cases were randomly divided into a medicine cup group (n = 47), a water cup group (n = 47) and a empty cup group (n = 46). The medicine cup group were treated by cupping therapy with a self-made medicine cup with 45 degrees C Chinese herb solution; the water cup group were treated with a cup with 45 degrees C water, and the empty cup group with a cup with nothing. Clinical symptoms and signs were observed for comparison of therapeutic effects. Clinically cured was 39 cases, and markedly effective was 8 cases in the medicine cup group; 20 cases were clinically cured, 22 cases were markedly effective and 5 cases were effective in the water cup group; 12 cases were clinically cured, 19 cases were markedly effective and 15 cases were effective in the empty cup group. There were significant differences in the ratio of cases of different therapeutic effects and the difference of pain score before and after treatment between the medicine cup group and the water cup group (P < 0.05), between the water cup group and the empty cup group (P < 0.05), and between the medicine cup group and the empty cup group (P < 0.01). The therapeutic effect of the distinctive medicine cup is better than the water cup group, and the water cup group is better than the empty cup group.
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ABSTRACT
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NRP-2 is a high-affinity kinase-deficient receptor for ligands belonging to the class 3 semaphorin and vascular endothelial growth factor families. NRP-2 has been detected on the surface of several types of human cancer cells, but its... more
NRP-2 is a high-affinity kinase-deficient receptor for ligands belonging to the class 3 semaphorin and vascular endothelial growth factor families. NRP-2 has been detected on the surface of several types of human cancer cells, but its expression and function in gastrointestinal (GI) cancer cells remains to be determined. We sought to determine the function of NRP-2 in mediating downstream signals
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To observe clinical therapeutic effect of moxibustion on abnormal blood lipids. The patients who did not take the medicine for regulating blood lipids and had still abnormal blood lipids after diet therapy for 3 months, were divided into... more
To observe clinical therapeutic effect of moxibustion on abnormal blood lipids. The patients who did not take the medicine for regulating blood lipids and had still abnormal blood lipids after diet therapy for 3 months, were divided into 4 groups according to different types of abnormal blood lipids. Forty cases selected in each group were again divided randomly into a treatment group and a control group. The treatment group were treated with moxibustion at Shousanli (LI 10), Zusanli (ST 36) and Shenque (CV 3) on the basis of diet therapy, and the control group only with the diet therapy. Their therapeutic effects were observed and compared after treatment of 90 days. There were significant differences between the treatment group and the control group in various groups of different types of abnormal blood lipids (P < 0.05). Moxibustion at Shousanli (LI 10), Zusanli (ST 36) and Shenque (CV 3) has a better therapeutic effect on abnormal blood lipids.
MshC catalyzes the ATP-dependent condensation of GlcN-Ins and cysteine to form Cys-GlcN-Ins, which is an intermediate in the biosynthetic pathway of mycothiol, i.e.,... more
MshC catalyzes the ATP-dependent condensation of GlcN-Ins and cysteine to form Cys-GlcN-Ins, which is an intermediate in the biosynthetic pathway of mycothiol, i.e., 1-D-myo-inosityl-2-(N-acetyl-L-cysteinyl)amido-2-deoxy-alpha-D-glucopyranoside (MSH or AcCys-GlcN-Ins). MSH is produced by Mycobacterium tuberculosis, members of the Actinomycetes family, to maintain an intracellular reducing environment and protect against oxidative and antibiotic induced stress. The biosynthesis of MSH is essential for cell growth, and therefore, the MSH biosynthetic enzymes present potential targets for inhibitor design. The formation of kinetically competent adenylated intermediates was suggested by the observation of positional isotope exchange (PIX) reaction using [betagamma-(18)O6]-ATP in the presence of cysteine. The PIX rate depends on the presence of cysteine and increases with concentrations of cysteine. The loss of PIX activity upon the addition of small concentrations of pyrophosphatase suggests that the PP(i) is free to dissociate from the active site of cysteine ligase into the bulk solution. The PIX activity is also eliminated at high concentrations of GlcN-Ins, consistent with the mechanism in which GlcN-Ins binds after cysteine-adenylate formation. This PIX analysis confirms that MshC catalyzes the formation of a kinetically competent cysteinyl-adenylate intermediate after the addition of ATP and cysteine.
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Nitric oxide (NO) is an important negative modulator of tubuloglomerular feedback responsiveness. We recently found that macula densa expresses α-, β-, and γ-splice variants of neuronal nitric oxide synthase 1 (NOS1), and NOS1β expression... more
Nitric oxide (NO) is an important negative modulator of tubuloglomerular feedback responsiveness. We recently found that macula densa expresses α-, β-, and γ-splice variants of neuronal nitric oxide synthase 1 (NOS1), and NOS1β expression in the macula densa increases on a high-salt diet. This study tested whether upregulation of NOS1β expression in the macula densa affects sodium excretion and salt-sensitive hypertension by decreasing tubuloglomerular feedback responsiveness. Expression levels of NOS1β mRNA and protein were 30- and five-fold higher, respectively, than those of NOS1α in the renal cortex of C57BL/6 mice. Furthermore, macula densa NO production was similar in the isolated perfused juxtaglomerular apparatus of wild-type (WT) and nitric oxide synthase 1α-knockout (NOS1αKO) mice. Compared with control mice, mice with macula densa-specific knockout of all nitric oxide synthase 1 isoforms (MD-NOS1KO) had a significantly enhanced tubuloglomerular feedback response and after...
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A series of Gd 2Zr 2O 7 (GZO) single buffer layers with different thicknesses were epitaxially grown on highly textured Ni-5 at.% W tapes using pulsed laser deposition. These allow the subsequent growth of high-quality superconducting YBa... more
A series of Gd 2Zr 2O 7 (GZO) single buffer layers with different thicknesses were epitaxially grown on highly textured Ni-5 at.% W tapes using pulsed laser deposition. These allow the subsequent growth of high-quality superconducting YBa 2Cu 3O 7-delta layers. The superconducting transition temperature T c reaches a maximum value of 92.4 K as well as a narrow transition width of 0.8 K for the optimized GZO layer thickness. The inductive measurements show the critical current density as high as 1.2 MA/cm 2 at 77 K in self-field, indicating that a GZO single buffer layer is a suitable alternative for simplifying the second generation high T c superconducting coated conductors architecture.
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BACKGROUND: Fibrolamellar carcinoma, a rare variant of hepatocellular carcinoma, and focal nodular hyperplasia, a benign lesion, are rare hepatic lesions that are known to occur in young women with noncirrhotic livers. Some have suggested... more
BACKGROUND: Fibrolamellar carcinoma, a rare variant of hepatocellular carcinoma, and focal nodular hyperplasia, a benign lesion, are rare hepatic lesions that are known to occur in young women with noncirrhotic livers. Some have suggested that fibrolamellar carcinoma might be the malignant counterpart of focal nodular hyperplasia. The coexistence of the 2 lesions is very rare.CASES: Two cases of fibrolamellar hepatocellular carcinoma arising in a background of focal nodular hyperplasia followed long-term oral contraception, and 1 of the 2 occurred during pregnancy.CONCLUSION: Distinguishing fibrolamellar carcinoma from focal nodular hyperplasia has important implications for treatment and prognosis. One should be aware of such conditions, especially in patients with a long history of oral contraception.
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McCarty MF, Wey J, Stoeltzing O, Liu W, Fan F, Bucana C, Mansfield PF, Ryan AJ, Ellis LMZD6474, a vascular endothelial growth factor receptor tyrosine kinase inhibitor with additional activity against epidermal growth factor receptor tyrosine kinase, inhibits orthotopic growth and angiogenesis of...more
ABSTRACT
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ABSTRACT
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Small tumor vessels are composed of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). These cells have been shown to communicate with each other via cytokine signaling during neovascularization. We previously demonstrated... more
Small tumor vessels are composed of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). These cells have been shown to communicate with each other via cytokine signaling during neovascularization. We previously demonstrated that interleukin-1β (IL-1β) leads to induction of vascular endothelial growth factor (VEGF) in human colon carcinoma cells. As pericytes play a role in regulating EC function, we
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Angiogenesis is essential for the growth of both primary and metastatic tumors. This process, more complex than was previously thought, requires the coordinated activities of multiple factors and cell types. For tumors to develop a... more
Angiogenesis is essential for the growth of both primary and metastatic tumors. This process, more complex than was previously thought, requires the coordinated activities of multiple factors and cell types. For tumors to develop a neovascular blood supply, tumor and host cells must secrete pro-angiogenic factors that offset the activities of inhibitory angiogenic factors. In addition, the newly derived tumor endothelium must respond to survive in a relatively caustic microenvironment. Thus, endothelial-cell survival factors are essential in the maintenance of this neovasculature. Because redundant factors and pathways regulate angiogenesis, inhibition of any single pathway is unlikely to lead to prolonged response in most patients with solid malignancies. Since anti-angiogenic therapy is unlikely to induce tumor regression, the criteria for efficacy must be evaluated by means other than the standard criteria used to evaluate cytotoxic chemotherapy regimens. Understanding the basic principles that drive tumor angiogenesis will lead to the development of therapies that will likely prolong survival without the toxicity associated with standard chemotherapy.
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This study describes a high-throughput fluorescence dilution technique to measure the albumin reflection coefficient (σAlb) of isolated glomeruli. Rats were injected with fluorescein isothiocyanate-dextran 250 (75 mg/kg) and the glomeruli... more
This study describes a high-throughput fluorescence dilution technique to measure the albumin reflection coefficient (σAlb) of isolated glomeruli. Rats were injected with fluorescein isothiocyanate-dextran 250 (75 mg/kg) and the glomeruli were isolated in a 6% bovine serum albumin solution. Changes in the fluorescence of the glomerulus due to water influx in response to an imposed oncotic gradient was used to determine σAlb. Adjustment of the albumin concentration of the bath from 6% to 5%, 4%, 3%, and 2 % produced a 10%, 25%, 35%, and 50% decrease in the fluorescence of the glomeruli. Pretreatment of glomeruli with protamine sulfate (2 mg/ml) or TGF-β1 (10 ng/ml) decreased σAlb from 1 to 0.54 and 0.48, respectively. Water and solute movement were modeled using the Kedem-Katchalsky equations and the measured responses closely fit the predicted behavior, indicating that loss of albumin by solvent drag or diffusion is negligible in comparison to the movement of water. We also found th...
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Angiogenesis is essential for the growth and metastasis of solid tumors. The angiogenic process includes not only development of new blood vessels but also maintenance of the existing vasculature. Recent studies have demonstrated that... more
Angiogenesis is essential for the growth and metastasis of solid tumors. The angiogenic process includes not only development of new blood vessels but also maintenance of the existing vasculature. Recent studies have demonstrated that several factors induce angiogenesis and also function as endothelial cell survival factors. Vascular endothelial growth factor, a potent angiogenic factor, is an endothelial cell survival factor whose tyrosine kinase receptors are limited to endothelial cells. Members of the angiopoietin family also bind to an endothelial cell-specific tyrosine kinase receptor. Angiopoietin-1 has been shown to stabilize endothelial cell networks, whereas angiopoietin-2 is antagonistic to angiopoietin-1 and destabilizes endothelial cell networks. Pericytes contribute to endothelial cell stabilization by cell-cell contact, secretion of survival factors, or both. In addition, integrins may function as endothelial cell survival factors by numerous mechanisms after binding to the extracellular matrix. The effects of many endothelial cell survival factors act in concert with vascular endothelial growth factor to enhance this essential step in angiogenesis. Targeting any of the aforementioned mechanisms for endothelial cell survival may provide novel therapeutic antineoplastic strategies.
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Tumor angiogenesis is a complicated process that is regulated by numerous factors simultaneously and in a coordinated fashion. Angiogenic factors drive the process of neovascularization, but the initiation of angiogenesis involves priming... more
Tumor angiogenesis is a complicated process that is regulated by numerous factors simultaneously and in a coordinated fashion. Angiogenic factors drive the process of neovascularization, but the initiation of angiogenesis involves priming of endothelial cells so that they will respond to mitogenic stimuli. The angiopoietins (Ang) -1 and -2 mediate endothelial cell stability through binding to their endothelial cell-specific receptor, Tie-2. Ang-1 leads to endothelial cell stability, and, in vivo, to an actual decrease in angiogenesis. This is likely due to its ability to enhance adhesion to the perivascular tissues. In contrast, Ang-2 leads to endothelial cell instability and may be an initiating factor in angiogenesis, priming endothelial cells for mitogenic signals. Thus, a novel antiangiogenic strategy may be one that leads to enhanced endothelial cell stability, thereby protecting endothelial cells from standard angiogenic stimuli. This may ultimately lead to tumor dormancy by transforming a rapidly growing tumor into an indolent tumor.
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Angiogenesis is a dynamic process essential for primary tumor growth and metastases. New insights into the basic understanding of the biologic processes responsible for angiogenesis have led to the characterization of potential... more
Angiogenesis is a dynamic process essential for primary tumor growth and metastases. New insights into the basic understanding of the biologic processes responsible for angiogenesis have led to the characterization of potential therapeutic targets. Several strategies for the development of antiangiogenic therapeutic modalities have been employed, including agents that (1) decrease the activity of specific angiogenic factors, (2) decrease th$ activity of endothelial survival factors, (3) increase the activity of naturally occurring antiangiogenic agents, or (4) indirectly downregulate angiogenic and survivalfactor activity. Because antiangiogenic therapy is unlikely to induce tumor regression, the criteria for efficacy must be evaluated by means other than the standard response criteria used to evaluate cytotoxic chemotherapy. Further, the redundancy of molecules responsible for the angiogenic process suggests it is unlikely that a single antiangiogenic agent will provide prolonged inhibition of angiogenesis. Nevertheless, the understanding of the basic principles that drive tumor angiogenesis will lead to the development of therapies that will likely prolong survival without the toxicity associated with standard chemotherapy.
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... Comparison of the IC 50 s for each receptor is a means to assess compound selectivity between the two known β 3 integrins, α v β 3 and α IIb β 3 and to predict the effect of a compound in cell-based in vitro and in vivo efficacy... more
... Comparison of the IC 50 s for each receptor is a means to assess compound selectivity between the two known β 3 integrins, α v β 3 and α IIb β 3 and to predict the effect of a compound in cell-based in vitro and in vivo efficacy models. ...
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Retina-like image sensor is based on the non-uniformity of the human eyes and the log-polar coordinate theory. It has advantages of high-quality data compression and redundant information elimination. However, retina-like image sensors... more
Retina-like image sensor is based on the non-uniformity of the human eyes and the log-polar coordinate theory. It has advantages of high-quality data compression and redundant information elimination. However, retina-like image sensors based on the CMOS craft have drawbacks such as high cost, low sensitivity and signal outputting efficiency and updating inconvenience. Therefore, this paper proposes a retina-like image sensor based on space-variant lens array, focusing on the circuit design to provide circuit support to the whole system. The circuit includes the following parts: (1) A photo-detector array with a lens array to convert optical signals to electrical signals; (2) a strobe circuit for time-gating of the pixels and parallel paths for high-speed transmission of the data; (3) a high-precision digital potentiometer for the I-V conversion, ratio normalization and sensitivity adjustment, a programmable gain amplifier for automatic generation control(AGC), and a A/D converter fo...
In this article, a method for fabricating the patterned liquid crystal photoalignment structures, in a single step, is proposed. A patterned quarter-wave plate formed by a photoaligned liquid crystalline polymer film is used as a... more
In this article, a method for fabricating the patterned liquid crystal photoalignment structures, in a single step, is proposed. A patterned quarter-wave plate formed by a photoaligned liquid crystalline polymer film is used as a photomask to generate photoaligned micro-patterns. Whereas other existing alternatives include complicated fabrication scheme, the proposed method provides an edge with simple one-step alignment. Moreover, the proposed method offers highly accurate, high resolution, multi micro-pattern alignment with great repeatability and therefore could find application in wide range of photonic and display devices demanding the micro-patterned, single of multi domain, alignment. In addition, the structure could be used for optical polarization information storage and patterned alignment structure storage, which could easily be reproduced.
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Revascularization is an essential process to compensate for cardiac underperfusion and, therefore, preserves cardiac function in the face of chronic ischemic injury. Recent evidence suggested a vital role of aldehyde dehydrogenase 2... more
Revascularization is an essential process to compensate for cardiac underperfusion and, therefore, preserves cardiac function in the face of chronic ischemic injury. Recent evidence suggested a vital role of aldehyde dehydrogenase 2 (ALDH2) in cardiac protection after ischemia. This study was designed to determine whether ALDH2 regulates chronic ischemia-induced angiogenesis and to explore the underlying mechanism involved. Moreover, the clinical impact of the ALDH2 mutant allele on the development of coronary collateral circulation (CCC) was evaluated. Mice limb ischemia was performed. Compared with wild-type, ALDH2 deletion significantly reduced perfusion recovery, small artery and capillary density, and increased muscle atrophy in this ischemic model. In vitro, ALDH2-knockdown reduced proliferation, migration and hypoxia triggered endothelial tube formation of endothelial cells, the effects of which were restored by ALDH2 transfection. Further examination revealed that ALDH2 regu...
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The degradation of underwater image obtained by range gated pulsed laser imaging system is mainly caused by scattering and absorption of in-water particles. Although the use of blind deconvolution of image restoration is a widely known... more
The degradation of underwater image obtained by range gated pulsed laser imaging system is mainly caused by scattering and absorption of in-water particles. Although the use of blind deconvolution of image restoration is a widely known concept, little literatures have discussed in detail its application in the problem of restoration of underwater images. In order to extend the imaging distance,
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A large number of pseudogenes have been found to be transcribed in human cancers. However, only a few pseudogenes are functionally characterized. Here, we identified a transcribed pseudogene of vascular endothelial growth factor... more
A large number of pseudogenes have been found to be transcribed in human cancers. However, only a few pseudogenes are functionally characterized. Here, we identified a transcribed pseudogene of vascular endothelial growth factor receptor-1 (VEGFR1), or fmsrelated tyrosine kinase 1 (FLT1), in human colorectal cancer (CRC) cells. Interestingly, this pseudogene (designated as FLT1P1) was found to be transcribed bidirectionally and functionally modulated cognate VEGFR1 protein expression in the cells. Mechanistically, expression of FLT1P1 antisense transcript not only inhibited the VEGFR1 expression, but also inhibited non-cognate VEGF-A expression through interaction with miR-520a. Perturbation of FLT1P1 expression by RNA interference (RNAi) markedly inhibited tumor cell proliferation and xenograft tumor growth. This study identifies FLT1P1 antisense as a critical regulator of VEGFR1 and VEGF-A expression in CRC cells, and highlights its role in regulation of the pathogenesis of CRC. T...
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Inflammation and oxidative stress have been implicated in various pathological processes including skin tumorigenesis. Skin cancer is the most common form of cancer responsible for considerable morbidity and mortality, the treatment... more
Inflammation and oxidative stress have been implicated in various pathological processes including skin tumorigenesis. Skin cancer is the most common form of cancer responsible for considerable morbidity and mortality, the treatment progress of which remains slow though. Therefore, chemoprevention and other strategies are being considered. Menthol has shown high anticancer activity against various human cancers, but its effect on skin cancer has never been evaluated. We herein investigated the chemopreventive potential of menthol against 9,10-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation, oxidative stress and skin carcinogenesis in female ICR mice. Pretreatment with menthol at various doses significantly suppressed tumor formation and growth, and markedly reduced tumor incidence and volume. Moreover, menthol inhibited TPA-induced skin hyperplasia and inflammation, and significantly suppressed the expression of cyclooxygenase-2 (COX-...