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1.
J Biol Chem ; 287(46): 38531-42, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23007393

RESUMO

Skeletal muscle formation and regeneration require myoblast fusion to form multinucleated myotubes or myofibers, yet their molecular regulation remains incompletely understood. We show here that the levels of extra- and/or pericellular chondroitin sulfate (CS) chains in differentiating C2C12 myoblast culture are dramatically diminished at the stage of extensive syncytial myotube formation. Forced down-regulation of CS, but not of hyaluronan, levels enhanced myogenic differentiation in vitro. This characteristic CS reduction seems to occur through a cell-autonomous mechanism that involves HYAL1, a known catabolic enzyme for hyaluronan and CS. In vivo injection of a bacterial CS-degrading enzyme boosted myofiber regeneration in a mouse cardiotoxin-induced injury model and ameliorated dystrophic pathology in mdx muscles. Our data suggest that the control of CS abundance is a promising new therapeutic approach for the treatment of skeletal muscle injury and progressive muscular dystrophies.


Assuntos
Sulfatos de Condroitina/fisiologia , Regulação da Expressão Gênica , Hialuronoglucosaminidase/metabolismo , Músculo Esquelético/metabolismo , Distrofias Musculares/fisiopatologia , Animais , Cardiotoxinas/metabolismo , Diferenciação Celular , Células Cultivadas , Sulfatos de Condroitina/química , Glicosaminoglicanos/metabolismo , Ácido Hialurônico/química , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Desenvolvimento Muscular , Distrofias Musculares/terapia , Proteoglicanas/metabolismo , Regeneração , Fatores de Tempo
2.
Dalton Trans ; 51(47): 18203-18212, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36398737

RESUMO

Silanones (OSiR2) are highly reactive species that readily convert to oligomeric siloxane (O-SiR2)n. The coordination of silanones to transition metal fragments to afford silanone-coordinated complexes is a reliable silanone stabilization method. Herein, a pyridine-stabilized silanone molybdenum complex Cp*(OC)2Mo{OSiMes2(py)}(SiMe3) (2b, Cp*: η5-C5Me5, Mes: 2,4,6-Me3C6H2, and py: pyridine) was synthesized by reacting the silyl(silylene) complex Cp*(OC)2Mo(SiMes2)(SiMe3) (4b) with pyridine-N-oxide in pyridine. X-ray crystal structure analysis revealed that the geometry of complex 2b is similar to those of the previously synthesized DMAP-stabilized analogue Cp*(OC)2Mo{OSiMes2(DMAP)}(SiMe3) (2a, DMAP: 4-(dimethylamino)pyridine). The SiO and Mo-O bond distances in 2b are similar to those observed in 2a, but the N-Si coordination bond of 2b is slightly longer (approximately 0.05 Å) than that of 2a, indicating weaker pyridine coordination than that of DMAP. The reaction of 2a with excess PMe3 in C6D6 at room temperature for 28 h afforded Cp*(OC)2Mo(PMe3)(SiMe3) (5c) in a 43% NMR yield. In contrast, reacting 2b with excess PMe3 in C6D6 at room temperature for 9 h afforded 5c and the five-membered metallacyclic carbene complex Cp*(OC)Mo(C(SiMe3)OSiMes2O)(PMe3) (6) in 10% and 41% NMR yields, respectively. The reactions of pyridine-stabilized silanone complexes Cp*(OC)2M(OSiMes2(py))(SiMe3) (M = Mo (2b) and W (1b)) with acetone proceeded via pyridine elimination, coordination of acetone to the Si center in the silanone ligand, and elimination of HSiMe3 to give Cp*(OC)2M{OSiMes2OC(Me)CH2} (M = Mo (8) and W (9)) in high yields.

3.
Materials (Basel) ; 14(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200651

RESUMO

Pure titanium was treated by atmospheric oxidation, and the effect of the treatment temperature on its performance was studied. X-ray diffraction, scanning electron microscopy, wear testing, and scratch testing were used to evaluate the performance of the treated specimens. In order to evaluate the difficulty of compound formation during the different processing temperatures, Gibbs free energy was calculated. The experimental results show that the surface hardness of the sample can be improved at a certain oxidation treatment temperature. When the processing temperature is 850 °C, the surface hardness reaches the maximum value. The results of the scratch testing show that the hardened layer produced at this processing temperature has excellent peeling resistance. In addition, the wear depth and wear width are also at their minimum values at this processing temperature. Since the specimen treated at a processing temperature of 850 °C provides sufficiently high surface hardness and wear resistance in this research report, it is considered to be the optimal condition during practical application.

4.
Auris Nasus Larynx ; 47(5): 763-768, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32376070

RESUMO

OBJECTIVE: Acoustic therapies including hearing aids and tinnitus control instruments are widely used in Japan but without high levels of evidence. The outpatient hearing aid clinic at our institution fits patients with hearing aids and instructs patients on how to use them to control tinnitus if present. In this study, we examined the effects of this approach on tinnitus. METHODS: One hundred and eleven of 138 patients who visited our hearing aid clinic from April 2016 to September 2018 purchased hearing aids after fitting. Sixty-six of these patients (31 men, 35 women; mean age 78.0 ± 8.0 years) had both hearing loss and tinnitus and were enrolled. The tinnitus was bilateral in 41 patients and unilateral in 25 (poor hearing ear, n = 16, good hearing ear, n = 9). Hearing aids were worn bilaterally by 23 patients and unilaterally by 43 (89 devices). Seventeen of the 23 patients wearing bilateral hearing aids had bilateral tinnitus and 6 had unilateral tinnitus, i.e., in 40 ears, the tinnitus side matched the hearing aid side (40 devices) and in 6 ears did not (6 devices). Twenty-four of 43 patients wearing unilateral hearing aids had bilateral tinnitus, meaning that in 24 ears the tinnitus side matched the hearing aid side (24 devices). In six of the remaining 19 cases with unilateral tinnitus, the hearing aid and tinnitus were on the same side (6 devices) and in 13 were on opposite sides (13 devices). Changes in the Tinnitus Handicap Inventory (THI), visual analog scale (VAS, for tinnitus discomfort, severity, and persistence), and Hospital Anxiety and Depression Scale scores were measured immediately before using a hearing aid and 12 months later. RESULTS: Significant effects of hearing aids on tinnitus were observed in all subjects (THI, p = 0.0000030), VAS (severity, p = 0.000000066; discomfort, p = 0.0000013). Significant effects were observed with bilateral hearing aids (THI, p = 0.0012; VAS for severity, p = 0.00069; VAS for discomfort, p = 0.00052) and with unilateral hearing aids (THI, p = 0.00055; VAS for severity, p = 0.000034; VAS for discomfort, p = 0.00007). Spearman's rank correlation coefficient showed a significant positive correlation between the THI and VAS scores (p = 0.0033). In cases of bilateral tinnitus, significant differences were observed with bilateral hearing aids (THI, p = 0.011; VAS for severity, p = 0.0019; VAS for discomfort; p = 0.020) and with unilateral hearing aids (THI, p = 0.00069; VAS for severity, p = 0.00071; VAS for discomfort, p = 0.000093). CONCLUSION: Acoustic therapy using hearing aids was effective for tinnitus. Even when bilateral, a unilateral hearing aid is able to improve tinnitus. When unilateral, the ipsilateral hearing aid is able to improve tinnitus.


Assuntos
Auxiliares de Audição , Perda Auditiva/reabilitação , Zumbido/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Perda Auditiva/complicações , Humanos , Masculino , Gravidade do Paciente , Estudos Retrospectivos , Zumbido/complicações
5.
J Clin Invest ; 110(11): 1619-28, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12464667

RESUMO

Interactions between endothelial cells (ECs) and perivascular mural cells (MCs) via signaling molecules or physical contacts are implicated both in vascular remodeling and maintenance of vascular integrity. However, it remains unclear how MCs regulate the morphogenic activity of ECs to form an organized vascular architecture, comprising distinct artery, vein, and capillary, from a simple mesh-like network. A clear elucidation of this question requires an experimental model system in which ECs are separated from MCs and yet form vascular structures. Here we report that injection of an antagonistic mAb against PDGFR-beta into murine neonates provides such an experimental system in the retina by completely blocking MC recruitment to developing vessels. While a vascular network was formed even in the absence of MCs, it was poorly remodeled and leaky. Using this vascular system ideal for direct assessment of the activities of MC-derived molecules, we show that addition of recombinant modified angiopoietin-1 restored a hierarchical vasculature, and also rescued retinal edema and hemorrhage in the complete absence of MCs. These observations demonstrate the potential of Ang1 as a new therapeutic modality for MC dropout in diseases such as diabetic retinopathies.


Assuntos
Indutores da Angiogênese/farmacologia , Vasos Sanguíneos/fisiologia , Glicoproteínas de Membrana/farmacologia , Neovascularização Fisiológica/fisiologia , Angiopoietina-1 , Animais , Vasos Sanguíneos/citologia , Vasos Sanguíneos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Neovascularização Fisiológica/efeitos dos fármacos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteínas Recombinantes/farmacologia , Vasos Retinianos/citologia , Vasos Retinianos/efeitos dos fármacos
6.
Materials (Basel) ; 8(10): 7180-7190, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-28793629

RESUMO

Aluminum foam is usually used as the core of composite materials by combining it with dense materials, such as in Al foam core sandwich panels and Al-foam-filled tubes, owing to its low tensile and bending strengths. In this study, all-Al foam-filled tubes consisting of ADC12 Al-Si-Cu die-cast aluminum alloy foam and a dense A1050 commercially pure Al tube with metal bonding were fabricated by friction welding. First, it was found that the ADC12 precursor was firmly bonded throughout the inner wall of the A1050 tube without a gap between the precursor and the tube by friction welding. No deformation of the tube or foaming of the precursor was observed during the friction welding. Next, it was shown that by heat treatment of an ADC12-precursor-bonded A1050 tube, gases generated by the decomposition of the blowing agent expand the softened ADC12 to produce the ADC12 foam interior of the dense A1050 tube. A holding time during the foaming process of approximately tH = 8.5 min with a holding temperature of 948 K was found to be suitable for obtaining a sound ADC12-foam-filled A1050 tube with sufficient foaming, almost uniform pore structures over the entire specimen, and no deformation or reduction in the thickness of the tube.

7.
Invest Ophthalmol Vis Sci ; 44(1): 393-402, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12506101

RESUMO

PURPOSE: Ischemia-induced neovascularization can cause catastrophic loss of vision in retinal disorders such as diabetic retinopathy. Recent studies have shown that the angiopoietin-Tie2 system is a major regulator of vascular integrity and is involved in pathologic angiogenesis. In the study described herein, the role of these molecules in ischemic retinal disorders was investigated. METHODS: Human epiretinal membranes were examined by immunohistochemistry, In situ hybridization, and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Effects of angiopoietins on tube formation were studied in vitro in bovine retinal capillary endothelial cells (BRECs) and in a murine model of ischemia-induced retinal neovascularization. RESULTS: In human epiretinal membranes surgically obtained from eyes with ischemic retinal disorders, substantial upregulation of angiopoietin 2 (Ang2) and the receptor Tie2 was recorded than in those from eyes with nonischemic diseases, whereas expression of Ang1 was constant in all membranes. Both Ang1 and Ang2 promoted tube-forming activity and enhanced the effects of vascular endothelial growth factor (VEGF) in cultured BRECs. Soluble Tie2 fusion protein (sTie2-Fc), which precluded modulation of VEGF-dependent tube formation by the angiopoietins, suppressed both VEGF and hypoxia-conditioned, medium-induced tube-forming activity in BRECs. Intravitreal injection of sTie2-Fc, soluble Flt-1 fusion protein (sFlt-1-Fc), and both chimeric proteins suppressed retinal angiogenesis in a murine model of retinal ischemia in the order of sTie2-Fc < sFlt-1-Fc < sTie2-Fc+sFlt-1-Fc. CONCLUSIONS: These results reinforce the substantial role of the angiopoietins/Tie2 system in ischemia-induced angiogenesis as well as the VEGF system and suggest that combined inhibition of Tie2 and VEGF signaling may be more effective in halting or preventing pathologic angiogenesis in ischemic retinal disorders.


Assuntos
Indutores da Angiogênese/metabolismo , Isquemia/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas , Neovascularização Retiniana/metabolismo , Vasos Retinianos/metabolismo , Adulto , Idoso , Indutores da Angiogênese/genética , Indutores da Angiogênese/farmacologia , Angiopoietina-1 , Angiopoietina-2 , Animais , Bovinos , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/efeitos dos fármacos , Membrana Epirretiniana/etiologia , Membrana Epirretiniana/metabolismo , Membrana Epirretiniana/patologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Isquemia/complicações , Linfocinas/farmacologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Receptor TIE-2 , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/patologia , Vasos Retinianos/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
8.
Invest Ophthalmol Vis Sci ; 43(6): 2007-14, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12037012

RESUMO

PURPOSE: It has been reported that 17beta-estradiol (E2) may enhance the proliferation of bovine retinal vascular endothelial cells (BRECs) by increasing the expression of VEGFR-2 and VEGF. The hypothesis in the current study was that estrogen may contribute to fetal vascular development and the cessation of exposure to estrogen of premature infants on birth may have an inhibitory effect on retinopathy of prematurity (ROP). Because ROP is thought to develop under relative hypoxia after exposure to high-dose oxygen, this study was conducted to investigate how estrogen modulates hypoxia-induced VEGF in BRECs and mouse ROP. METHODS: Gene expression of VEGF and hypoxia-inducible factor (HIF)-1alpha were studied in BRECs, with or without E2, under normoxia and hypoxia (1% O2). A binding assay was performed to determine whether estrogen interferes with HIF-1-mediated induction of VEGF. In a mouse ROP model, effects of E2 were evaluated by avascular area, subsequent extraretinal neovascularization, and retinal expression of the VEGF gene, by administering E2 during hyperoxia (75% O2) and/or after exposure to room air. RESULTS: Hypoxia-induced VEGF mRNA in BRECs was reduced dose dependently by 1 to 100 nM E2. E2 reduced hypoxia-induced binding of HIF-1 to the VEGF promoter site and reduced the HIF-1alpha mRNA level. In mouse ROP, injection of E2 during hyperoxia increased retinal VEGF mRNA and reduced the retinal avascular area at the end of hyperoxia. E2 treatment during the normoxia that followed reduced VEGF mRNA and extraretinal neovascularization. Treatment with E2 throughout both periods significantly improved retinopathy. CONCLUSIONS: Estrogen may function as a significant modulator of the level of VEGF mRNA under different oxygen conditions and could serve as a prophylactic agent for ROP.


Assuntos
Fatores de Crescimento Endotelial/genética , Endotélio Vascular/efeitos dos fármacos , Estrogênios/farmacologia , Hipóxia/metabolismo , Linfocinas/genética , Neovascularização Retiniana/metabolismo , Vasos Retinianos/efeitos dos fármacos , Retinopatia da Prematuridade/metabolismo , Fatores de Transcrição , Animais , Northern Blotting , Bovinos , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/patologia , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Recém-Nascido , Linfocinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Neovascularização Retiniana/patologia , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Retinopatia da Prematuridade/patologia , Tamoxifeno/farmacologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Br J Pharmacol ; 137(6): 901-9, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12411422

RESUMO

1. Vascular endothelial growth factor (VEGF) plays an important role in the neovascularization of ischaemic retinal diseases such as proliferative diabetic retinopathy. We determined that bucillamine, an anti-rheumatic drug, inhibits the VEGF production induced by hypoxia in bovine retinal microcapillary endothelial cells (BREC). To further clarify the inhibitory mechanism, we investigated the possible mechanism by which bucillamine exerts this inhibitory effect. 2. Bucillamine (100 micro M) decreased the hypoxia-induced increase of VEGF mRNA by 54.5% (P<0.001). Bucillamine (100 micro M) reduced the hypoxia-induced VEGF content in culture media by 29.0% (P<0.001), while monosulfydryl drugs, N-acetylcysteine and D-penicillamine, did not. 3. Bucillamine (100 micro M) did not affect VEGF mRNA half-life (hypoxia, 4.3 h; hypoxia+bucillamine, 3.9 h; normoxia, 2.7 h; normoxia+bucillamine, 2.7 h). 4. Reporter gene studies revealed that bucillamine reduced transcriptional activity in the 5'-flanking region of the VEGF gene by 74.0%. Hypoxia stimulated binding activity of BREC nuclear protein to a hypoxia responsive element (HRE), which was decreased by bucillamine. 5. Bucillamine inhibited hypoxic-induction of HIF-1alpha mRNA by 73.1% (P<0.001). Bucillamine also inhibited spontaneous VEGF mRNA expression by 26.6%. Furthermore, it inhibited activity of VEGF promoter and decreased binding activity to Sp1 and HRE, but did not alter AP1 and AP2 activity in normoxia. 6. These data suggest that bucillamine inhibits hypoxic induction of VEGF through inhibition of HIF-1 induction and binding activity in BREC. Bucillamine also inhibits the spontaneous expression of VEGF mRNA by its effect on Sp1 and HRE binding.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cisteína/análogos & derivados , Cisteína/farmacologia , Linfocinas/efeitos dos fármacos , Animais , Bovinos , Hipóxia Celular/fisiologia , Linhagem Celular , Células Cultivadas , Proteínas de Ligação a DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Luciferases/genética , Luciferases/metabolismo , Linfocinas/genética , Linfocinas/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/efeitos dos fármacos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-2 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
10.
Mol Vis ; 10: 608-17, 2004 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-15354084

RESUMO

PURPOSE: The angiopoietin (Ang)/Tie-2 system may play a role in vascular integrity and angiogenesis. In this study, we investigated alterations of the gene expression of Ang-1 and Ang-2 in the retinas of streptozotocin (STZ) induced diabetic rats. METHODS: In situ hybridization, reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analyses were performed to determine the mRNA and protein content for Ang-1 and Ang-2 and the Tie2 receptor in the retinas of STZ diabetic and age matched control rats. RESULTS: Using in situ hybridization analysis, Ang-1, Ang-2, and Tie2 mRNA expression was observed in the ganglion cell layer (GCL) and the inner nuclear layer (INL). While Ang-2 mRNA expression did not changed after 2 weeks, 1 month, or 3 months of STZ induced diabetes, it was increased in the GCL and slightly elevated in the INL after 6 months of diabetes. In contrast, Ang-1 and Tie2 mRNA expression was stable at every timepoint during 6 months of STZ induced diabetes. RT-PCR and western blot analyses confirmed the increase of Ang-2 expression after 6 months of diabetes. Furthermore, double staining of alpha-smooth muscle actin (alphaSMA) and Ang-2 mRNA demonstrated that the SMA positive cells surrounding Ang-2-expressing cells were decreased in the GCL. CONCLUSIONS: Diabetes increases Ang-2 expression in the GCL accompanied by a reduction of alphaSMA positive perivascular cells. These changes may suggest a role for Ang-2 in the mechanism of pericyte loss in diabetic retinopathy.


Assuntos
Angiopoietina-1/genética , Angiopoietina-2/genética , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Regulação da Expressão Gênica , Receptor TIE-2/genética , Retina/metabolismo , Angiopoietina-1/metabolismo , Angiopoietina-2/metabolismo , Animais , Western Blotting , Técnicas Imunoenzimáticas , Hibridização In Situ , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor TIE-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Jpn J Ophthalmol ; 46(3): 270-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12063036

RESUMO

PURPOSE: It has been reported that vitronectin receptor-type integrins mediate vascular cell proliferation and migration. In this study, we investigated the expression of vitronectin receptor-type integrins and osteopontin in ischemia-induced retinal neovascularization, and examined the role of osteopontin in angiogenesis as a ligand of vitronectin receptor-type integrins. METHODS: Retinal neovascularization was produced by exposing C57BL/6J mice to 75% oxygen from postnatal day (P) 7 to P12. Expression of vitronectin receptor-type integrins and osteopontin was assessed by Northern blot analysis, in situ hybridization, and immunofluorescence. The role of osteopontin in retinal angiogenesis was evaluated by tube formation assay using cultured bovine retinal microcapillary endothelial cells. RESULTS: In the murine model, integrin alpha(v) mRNA was increased from P14 with a 2.6-fold peak response observed on P19, when retinal neovascularization was remarkable. Indirect immunofluorescence for vitronectin receptor-type integrins revealed prominent expression of integrin alpha(v)beta3/beta5 in the neovascular endothelial cells. Osteopontin mRNA was increased from P14, with a 2.0-fold peak response observed on P19. In situ hybridization demonstrated localization of osteopontin mRNA in neovascular tufts. Vascular endothelial growth factor-induced tube formation (8.3 +/- 0.6 mm/field) was inhibited significantly by treatment with anti-osteopontin antibody (4.8 +/- 0.7 mm/field, P <.001). CONCLUSIONS: These data suggest that increased expression of both vitronectin receptor-type integrins and osteopontin in ischemic retina contribute to vascular endothelial cell proliferation and to retinal vascular formation by promoting interaction between endothelial cells and extracellular matrix, which leads to retinal neovascularization.


Assuntos
Isquemia/complicações , Receptores de Vitronectina/metabolismo , Neovascularização Retiniana/metabolismo , Sialoglicoproteínas/metabolismo , Animais , Animais Recém-Nascidos , Northern Blotting , Células Cultivadas , Modelos Animais de Doenças , Imunofluorescência , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Osteopontina , RNA Mensageiro/metabolismo , Receptores de Vitronectina/genética , Neovascularização Retiniana/etiologia , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Sialoglicoproteínas/genética
12.
Auris Nasus Larynx ; 35(4): 572-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18272310

RESUMO

Laryngeal carcinoma is usually encountered in smoker men, and thyroid carcinoma is sometimes discovered incidentally during treatment for these patients. However, this coexistence of malignancies could occur in non-smoker female. We report an unusual case of multiple primary malignancies in the larynx and the thyroid gland. The laryngeal carcinoma was suspected to be related to the malignant transformation of the papillomas. The case suggests the importance of meticulous examination in the head and neck region for treatment of cervical metastatic lymph nodes with negative cytology in non-smoker female.


Assuntos
Carcinoma Papilar/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Transformação Celular Neoplásica/patologia , Neoplasias Laríngeas/diagnóstico , Neoplasias Primárias Múltiplas/diagnóstico , Papiloma/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Carcinoma Papilar/patologia , Carcinoma Papilar/radioterapia , Carcinoma Papilar/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Terapia Combinada , Feminino , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Laringe/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Pessoa de Meia-Idade , Esvaziamento Cervical , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/radioterapia , Neoplasias Primárias Múltiplas/cirurgia , Papiloma/patologia , Papiloma/radioterapia , Papiloma/cirurgia , Radioterapia Adjuvante , Fumar/efeitos adversos , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
13.
Proc Natl Acad Sci U S A ; 99(1): 383-8, 2002 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-11756651

RESUMO

Neuropilin (NRP) 1, previously identified as a neuronal receptor that mediates repulsive growth cone guidance, has been shown recently to function also in endothelial cells as an isoform-specific receptor for vascular endothelial growth factor (VEGF)(165) and as a coreceptor in vitro of VEGF receptor 2. However, its potential role in pathologic angiogenesis remains unknown. In the present study, we first show that VEGF selectively up-regulates NRP1 but not NRP2 via the VEGF receptor 2-dependent pathway. By NRP1 binding analysis, we showed that its induction by VEGF accompanies functional receptor expression. Endothelial proliferation stimulated by VEGF(165) was inhibited significantly by antibody perturbation of NRP1. In a murine model of VEGF-dependent angioproliferative retinopathy, intense NRP1 mRNA expression was observed in the newly formed vessels. Furthermore, selective NRP1 inhibition in this model suppressed neovascular formation substantially. These results suggest that VEGF cannot only activate endothelial cells directly but also can contribute to robust angiogenesis in vivo by a mechanism that involves up-regulation of its cognate receptor expression.


Assuntos
Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Linfocinas/metabolismo , Neovascularização Patológica , Proteínas do Tecido Nervoso/biossíntese , Animais , Aorta/citologia , Sítios de Ligação , Northern Blotting , Western Blotting , Bovinos , Divisão Celular , Núcleo Celular/metabolismo , Reagentes de Ligações Cruzadas/farmacologia , Relação Dose-Resposta a Droga , Imunoglobulina G/metabolismo , Camundongos , Neuropilina-1 , Análise de Sequência com Séries de Oligonucleotídeos , Ligação Proteica , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Retina/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fatores de Tempo , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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