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1.
Oral Dis ; 24(5): 741-748, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29316035

RESUMO

OBJECTIVE: Transcription factor EB (TFEB) is a master regulator of lysosomal biogenesis and plays an important role in various cancers. However, the function of TFEB in oral squamous cell carcinomas has not been examined. The aim of this study was to elucidate the role of TFEB in oral squamous cell carcinomas. MATERIALS AND METHODS: Expression levels of TFEB were examined in six different human oral squamous carcinoma cells: HSC2, HSC3, HSC4, SAS, OSC20, and SCC25. Knockdown of TFEB using small interfering RNA in HSC2 and HSC4 cells was performed. Cell morphology was observed by immunofluorescence microscopy. Cell proliferation, invasion, and adhesion were analyzed. RESULTS: Expression levels of TFEB were high in HSC2, moderate in HSC4 and SCC25, and low in HSC3 and OSC20 cells. Knockdown of TFEB did not affect proliferation of HSC2 and HSC4 cells, but did induced enlargement of lysosomes and endosomes in HSC4 cells. TFEB silencing reduced invasion and migration of these HSC cell squamous carcinoma cells; however, increased cell adhesion was also observed. CONCLUSION: TFEB knockdown reduces invasion and migration of cancer cells, likely through lysosomal regulation. Taken together, TFEB influences cell invasion and migration of oral squamous cell carcinomas.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Carcinoma de Células Escamosas/metabolismo , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Endossomos/patologia , Técnicas de Silenciamento de Genes , Humanos , Lisossomos/patologia , Neoplasias Bucais/metabolismo
2.
Oncogene ; 36(42): 5885-5896, 2017 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-28628120

RESUMO

Tumor suppressor TP53 is frequently mutated in colorectal cancer (CRC), and most mutations are missense type. Although gain-of-functions by mutant p53 have been demonstrated experimentally, the precise mechanism for malignant progression in in vivo tumors remains unsolved. We generated ApcΔ716 Trp53LSL•R270H villin-CreER compound mice, in which mutant p53R270H was expressed in the intestinal epithelia upon tamoxifen treatment, and examined the intestinal tumor phenotypes and tumor-derived organoids. Mutant Trp53R270H, but not Trp53-null mutation accelerated submucosal invasion with generation of desmoplastic microenvironment. The nuclear accumulation of p53 was evident in ApcΔ716 Trp53R270H/R270H homozygous tumors like human CRC. Although p53 was distributed to the cytoplasm in ApcΔ716 Trp53+/R270H heterozygous tumors, it accumulated in the nuclei at the invasion front, suggesting a regulation mechanism for p53 localization by the microenvironment. Importantly, mutant p53 induced drastic morphological changes in the tumor organoids to complex glandular structures, which was associated with the acquisition of invasiveness. Consistently, the branching scores of human CRC that carry TP53 mutations at codon 273 significantly increased in comparison with those of TP53 wild-type tumors. Moreover, allografted ApcΔ716 Trp53R270H/R270H organoid tumors showed a malignant histology with an increased number of myofibroblasts in the stroma. These results indicate that nuclear-accumulated mutant p53R270H induces malignant progression of intestinal tumors through complex tumor gland formation and acquisition of invasiveness. Furthermore, RNA sequencing analyses revealed global gene upregulation by mutant p53R270H, which was associated with the activation of inflammatory and innate immune pathways. Accordingly, it is possible that mutant p53R270H induces CRC progression, not only by a cell intrinsic mechanism, but also by the generation or activation of the microenvironment, which may synergistically contribute to the acceleration of submucosal invasion. Therefore, the present study indicates that nuclear-accumulated mutant p53R270H is a potential therapeutic target for the treatment of advanced CRCs.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Intestinais/patologia , Neoplasias Hepáticas/secundário , Mutação , Proteína Supressora de Tumor p53/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Progressão da Doença , Perfilação da Expressão Gênica , Humanos , Neoplasias Intestinais/genética , Neoplasias Intestinais/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Invasividade Neoplásica , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Microambiente Tumoral , Proteína Supressora de Tumor p53/metabolismo
3.
Chem Commun (Camb) ; 52(47): 7470-3, 2016 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-27198730

RESUMO

A visible-light-sensitive tin sulfide photocatalyst was designed based on a ubiquitous element strategy and density functional theory (DFT) calculations. Computational analysis suggested that tin monosulfide (SnS) would be more efficient than SnS2 as a photocathode for hydrogen production because of the low ionization potential and weak ionic character of SnS. To test this experimentally, nanoparticles of SnS were loaded onto a mesoporous electrode using a wet chemical method, and the bandgap of the synthesized SnS quantum dots was found to be tunable by adjusting the number of successive ionic layer adsorption and reaction (SILAR) cycles, which controls the magnitude of the quantum confinement effect. Efficient hydrogen production was achieved when the bandgap of SnS was wider than that of the bulk form.

4.
Nanoscale ; 7(29): 12510-5, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26139287

RESUMO

Metal oxide and quantum dot (QD) heterostructures have attracted considerable recent attention as materials for developing efficient solar cells, photocatalysts, and display devices, thus nanoscale imaging of trapped electrons in these heterostructures provides important insight for developing efficient devices. In the present study, Kelvin probe force microscopy (KPFM) of CdS quantum dot (QD)-grafted Cs4W11O36(2-) nanosheets was performed before and after visible-light irradiation. After visible-light excitation of the CdS QDs, the Cs4W11O36(2-) nanosheet surface exhibited a decreased work function in the vicinity of the junction with CdS QDs, even though the Cs4W11O36(2-) nanosheet did not absorb visible light. X-ray photoelectron spectroscopy revealed that W(5+) species were formed in the nanosheet after visible-light irradiation. These results demonstrated that excited electrons in the CdS QDs were injected and trapped in the Cs4W11O36(2-) nanosheet to form color centers. Further, the CdS QDs and Cs4W11O36(2-) nanosheet composite films exhibited efficient remote photochromic coloration, which was attributed to the quantum nanostructure of the film. Notably, the responsive wavelength of the material is tunable by adjusting the size of QDs, and the decoloration rate is highly efficient, as the required length for trapped electrons to diffuse into the nanosheet surface is very short owing to its nanoscale thickness. The unique properties of this photochromic device make it suitable for display or memory applications. In addition, the methodology described in the present study for nanoscale imaging is expected to aid in the understanding of electron transport and trapping processes in metal oxide and metal chalcogenide heterostructure, which are crucial phenomena in QD-based solar cells and/or photocatalytic water-splitting systems.

5.
Neurogastroenterol Motil ; 24(12): 1083-e564, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22882753

RESUMO

BACKGROUND: Oral sumatriptan administration has been reported to delay gastric emptying after liquid meals. The aim of this study was to determine whether delayed gastric emptying is caused by enhanced gastric accommodation, impaired antral contractions, or both using ultrasonography. METHODS: Ten healthy volunteers were enrolled in this randomized two-way crossover study. After overnight fasting, the subjects received the liquid meal 60 min after ingesting a 50 mg sumatriptan tablet with 50 mL of water or 50 mL of water alone (control). The cross-sectional area of the proximal stomach was measured in a supine position after every 100 mL. The frequency and amplitude of the antral contractions were measured in a slightly backward sitting position. The intragastric distribution of the liquid meal was assessed by calculating the proximal stomach/distal stomach ratio (prox/distal ratio). KEY RESULTS: The cross-sectional area after drinking 100, 200, and 300 mL of the liquid meal (oral sumatriptan vs control) was 34.49 vs 15.11 cm(2) (P = 0.0051), 48.00 vs 30.61 cm(2) (P = 0.0166), and 58.67 vs 47.19 cm(2) (P = 0.0125), respectively. There was no significant difference in the amplitude of contractions, contraction cycle, motility index, and prox/distal ratio (97.15 vs 97.93%, P = 0.0745; 19.42 vs 19.5 s, P= 0.8590; and 887.58 vs 889.22, P = 0.5751; 9.75 vs 8.41, P = 0.8785; respectively). CONCLUSIONS & INFERENCES: Oral sumatriptan administration enhanced gastric accommodation after the ingestion of liquid nutrients, but had no significant effect on antral contractions or intragastric distribution in healthy subjects.


Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Estômago/efeitos dos fármacos , Estômago/diagnóstico por imagem , Sumatriptana/farmacologia , Vasoconstritores/farmacologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Ultrassonografia , Adulto Jovem
6.
Colorectal Dis ; 14(10): e740-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22709354

RESUMO

AIM: A case-controlled study was performed to investigate the association of colonic angiectasia with other conditions and to identify risk factors for bleeding. METHOD: Information was collected from all patients who underwent colonoscopy at our hospital between January 2008 and December 2010. Data on 90 individuals with angiectasia [58 men; median age 69 (26-92) years] were compared with those of 180 individuals without angiectasia, matched for gender and age. RESULTS: Multivariate analysis showed that occult gastrointestinal bleeding [odds ratio (OR) 2.523; 95% confidence interval (CI) 1.238-5.142], liver cirrhosis (OR 13.195; 95% CI 3.502-49.711), chronic renal failure (OR 6.796; 95% CI 1.598-28.904) and valvular heart disease (OR 6.425; 95% CI 1.028-40.165) were identified as significant predictors of the presence of colonic angiectasia. Eight patients were diagnosed with bleeding from angiectasia. Cardiovascular disease (OR 22.047; 95% CI 1.063-457.345) and multiple angiectasias (P-value 0.0019) were identified as significant risk factors for active bleeding. Medication and a large size were not associated with an increased risk of bleeding. CONCLUSION: The presence of colonic angiectasia was associated with valvular heart disease, liver cirrhosis and chronic renal failure. Valvular heart disease and multiple lesions increased the risk of bleeding.


Assuntos
Angiodisplasia/etiologia , Doenças do Colo/etiologia , Hemorragia Gastrointestinal/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiodisplasia/diagnóstico , Estudos de Casos e Controles , Doenças do Colo/diagnóstico , Colonoscopia , Feminino , Hemorragia Gastrointestinal/diagnóstico , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco
8.
J Oral Pathol Med ; 35(10): 620-5, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17032395

RESUMO

BACKGROUND: Diffuse sclerosing osteomyelitis (DSO) of the mandible is characterized by mixed bone resorption and formation. METHODS: Immunohistopathology of DSO in the clinically acute and subacute phases was compared with healthy bone. RESULTS: Receptor activator of nuclear factor kappaB ligand (RANKL) was found in DSO lesions. When it was used in vitro to stimulate monocytes, cathepsin K expression was observed in mononuclear prefusion precursors and in multinuclear giant cells. Similarly, exacerbations of DSO were characterized by RANKL and induction of cathepsin K in mononuclear precursor cells, which subsequently seem to differentiate into osteoclasts or foreign body giant cells. The proportion of bone to soft tissue increased with the duration of disease. CONCLUSIONS: RANKL-driven osteoclastogenesis and acidic cysteine endoproteinase cathepsin K seem to play important roles in DSO as osteoclast-mediated bone resorption may represent the primary disease process later followed by new bone formation.


Assuntos
Reabsorção Óssea/metabolismo , Catepsinas/análise , Doenças Mandibulares/metabolismo , Osteomielite/metabolismo , Ligante RANK/análise , Adolescente , Adulto , Idoso , Animais , Estudos de Casos e Controles , Catepsina K , Feminino , Cabras , Cavalos , Humanos , Masculino , Doenças Mandibulares/patologia , Camundongos , Pessoa de Meia-Idade , Osteoclastos/citologia , Osteomielite/patologia , Coelhos
9.
Waste Manag ; 26(7): 752-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16650753

RESUMO

Nuclear waste repositories need highly durable cementitious materials to function for over thousands of years while resisting leaching and degradation. The durability of cementitious material can be effectively improved by reducing permeability and by changing cement hydrates to a less soluble matrix. This paper describes the properties of carbonated new cementitious materials containing belite-rich cement and gamma-2CaO.SiO2 as main components. In addition, the long-term leaching properties are investigated and compared with ordinary Portland cement by using a predictive leaching model.


Assuntos
Carbono/química , Materiais de Construção , Minerais/química
10.
J Neurophysiol ; 95(5): 2856-65, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16452254

RESUMO

Experiencing daily brief periods of unrestricted vision during early monocular form deprivation prevents or reduces the degree of resulting amblyopia. To gain insight into the neural basis for these "protective" effects, we analyzed the monocular and binocular response properties of individual neurons in the primary visual cortex (V1) of macaque monkeys that received intermittent unrestricted vision. Microelectrode-recording experiments revealed significant decreases in the proportion of units that were dominated by the treated eyes, and the magnitude of this ocular dominance imbalance was correlated with the degree of amblyopia. The sensitivity of V1 neurons to interocular spatial phase disparity was significantly reduced in all treated monkeys compared with normal adults. With unrestricted vision, however, there was a small but significant increase in overall disparity sensitivity. Binocular suppression was prevalent in monkeys with constant form deprivation but significantly reduced by the daily periods of unrestricted vision. If neurons exhibited consistent responses to stimulation of the treated eye, monocular response properties obtained by stimulation of the two eyes were similar. These results suggest that the observed protective effects of brief periods of unrestricted vision are closely associated with the ability of V1 neurons to maintain their functional connections from the deprived eye and that interocular suppression in V1 may play an important role in regulating synaptic plasticity of these monkeys.


Assuntos
Sensibilidades de Contraste/fisiologia , Neurônios/fisiologia , Privação Sensorial/fisiologia , Visão Monocular/fisiologia , Córtex Visual/fisiologia , Animais , Animais Recém-Nascidos , Comportamento Animal , Macaca mulatta , Orientação/fisiologia , Estimulação Luminosa/métodos , Fatores de Tempo , Córtex Visual/citologia , Córtex Visual/crescimento & desenvolvimento
11.
Int J Oral Maxillofac Surg ; 32(5): 563-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14759120

RESUMO

Oncocytoma is a rare salivary gland tumour consisting of oncocytes with many hyperplastic mitochondria. It usually occurs in the parotid gland. Because the features of oncocytoma resemble those of other benign and low-grade-malignant salivary gland tumours, clinical diagnosis is often challenging. This report presents the pathologic and imaging findings of an oncocytoma arising in the deep lobe of the left parotid gland in a 66-year-old man. Oncocytoma was diagnosed on the basis of histological, magnetic resonance imaging, and scintigraphic findings. The tumour showed accumulation of technetium-99m pertechnetate and decreased signal intensity on both T1- and T2-weighted magnetic resonance images.


Assuntos
Adenoma Oxífilo/patologia , Neoplasias Parotídeas/patologia , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/cirurgia , Idoso , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Parotídeas/diagnóstico por imagem , Neoplasias Parotídeas/cirurgia , Cintilografia , Compostos Radiofarmacêuticos , Pertecnetato Tc 99m de Sódio
12.
Arch Virol ; 147(1): 1-10, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11858230

RESUMO

JC virus (JCV) strains worldwide can be classified into various genotypes based on DNA sequence variations. To define the domains of the four major JCV genotypes in Asia, we collected urine samples at six unstudied sites: three in southeastern Asia, two in the central highlands and one in central Asia. DNA was extracted from urine samples, and used to amplify a 610-bp region of the viral genome. For each geographical site, we determined 16 to 31 sequences, from which a phylogenetic tree was constructed to unambiguously classify detected JCV isolates into distinct genotypes. From JCV genotype profiles at the sites studied here and elsewhere, the following conclusions were drawn. Although Af2 is the major genotype in Africa, this genotype also occurs in western and central Asia. B1-b mainly occurs in western and central Asia, including the central highlands. CY occurs in northeastern Asia with the southern boundary between China and southeast Asian countries. Although SC predominates in southeastern Asia, it also occurs in northern and central Asia at lower frequencies. In addition, a few minor JCV genotypes (B1-a, B2 and B3) occur at many sites. We discuss here the anthropological and medical significance of the present findings.


Assuntos
Vírus JC/classificação , Vírus JC/genética , Infecções por Polyomavirus/virologia , Adulto , Ásia , DNA Viral/urina , Variação Genética , Genética Populacional , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Prevalência , Análise de Sequência de DNA , Infecções Tumorais por Vírus/virologia
13.
J Biochem ; 130(6): 823-31, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11726283

RESUMO

Modifications occurring during the transformation of phagosomes into mature phagolysosomes were investigated in osteoclast-like cells (OCLs) and macrophages using latex beads as markers for the isolation of phagosomal compartments (LBC) at different time points after phagocytosis. In OCLs, newly formed LBC acquired cathepsin K, tartarate-resistant phosphatase (TRAP), lysosome-associated membrane protein-1 (Lamp-1), and cathepsin D, and rapidly lost annexin II in a time-dependent manner. The levels of Rab7 and c-Src in OCLs initially increased and then gradually decreased during the transformation from early to late endosomal LBC or phagolysosomes. Receptor activator of NF-kappaB (RANKL) significantly increased the LBC levels of cathepsin K, TRAP, and c-Src, whereas calcitonin decreased the LBC levels of cathepsin K, TRAP, and Rab7, indicating that the transformation of early to late endosomal elements and lysosomes in OCLs is also regulated by osteoclastogenesis regulatory factors. On the other hand, changes in the LBC levels of Lamp-1, cathepsin D, and annexin II in macrophages were comparable to those in OCLs. However, contrary to osteoclastic LBC, Rab7 levels of macrophage LBC decreased in a time-dependent manner. Macrophage LBC were devoid of cathepsin K, TRAP, and c-Src in all transformation stages. These observations suggest that OCLs and macrophages have different phagosome maturation mechanisms that involve the specific and regulated acquisition of markers from endocytic organelles. The results also demonstrate that the use of LBC is a useful system in which to identify and characterize molecules involved in these different endocytic pathways.


Assuntos
Endocitose/fisiologia , Macrófagos/fisiologia , Osteoclastos/fisiologia , Fagossomos/classificação , Animais , Medula Óssea , Calcitonina/farmacologia , Glicoproteínas/farmacologia , Cinética , Macrófagos/ultraestrutura , Masculino , Camundongos , Microscopia Eletrônica/métodos , Microesferas , Osteoclastos/efeitos dos fármacos , Osteoclastos/ultraestrutura , Osteoprotegerina , Fagossomos/fisiologia , Fagossomos/ultraestrutura , Receptores Citoplasmáticos e Nucleares , Receptores do Fator de Necrose Tumoral
14.
J Hepatol ; 35(2): 235-44, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11580146

RESUMO

BACKGROUND/AIMS: Intrahepatic cholangiocarcinoma (ICC) arises from intrahepatic bile duct epithelium and is the second most prevalent among primary liver cancers. The aim of this study was to clarify the mechanism of cholangiocarcinogenesis. METHODS: We studied the incidence of microsatellite instability (MSI) involving eight highly polymorphic microsatellite markers and alternations of the K-ras, p53 and mdm-2 genes in human ICC tissues. Overexpression of mdm-2 oncoprotein was also immunohistochemically studied. RESULTS: Of all 65 cases examined, K-ras gene mutation was found in three cases (4.6%) at codon 12. Analysis of p53 alterations was performed in 28 cases including 22 frozen samples and mutations were found in three cases (10.7%). Overexpression of mdm-2 protein was observed in 25 (41.7%) out of 60 cases analyzed. In 22 frozen samples, seven (31.8%) cases showed mdm-2 amplification and four (18.2%) cases revealed MSI-positive phenotype. Among the cases analyzed, all the tumors with mdm-2 amplification/overexpression harbored the wild-type p53 gene and all the microsatellite instability-positive cases were from mass-forming (MF) + periductal-infiltrating (PI) subtype. CONCLUSIONS: These results suggest that mdm-2 plays a role, which might be partially through inhibiting p53 activity, in cholangiocarcinogenesis and that M


Assuntos
Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/genética , Repetições de Microssatélites , Proteínas Nucleares , Adulto , Idoso , Sequência de Bases , Neoplasias dos Ductos Biliares/etiologia , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/etiologia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , DNA de Neoplasias/genética , Feminino , Expressão Gênica , Genes p53 , Genes ras , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Genético , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2
16.
J Biol Chem ; 276(49): 46031-8, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11592959

RESUMO

Glycosphingolipids and their metabolites play important roles in a variety of biological processes. Several signal molecules are localized in a glycolipid-enriched microdomain on the cell surface, and their signals are regulated by the glycolipid composition. However, the function of glycolipids in osteoclastogenesis has not been clearly understood. We found that D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP), a glucosylceramide synthase inhibitor, completely inhibits the osteoclast formation induced by macrophage-colony-stimulating factor and receptor activator of nuclear factor-kappa B ligand (RANKL) in a dose-dependent manner. Expression of RANK, the receptor of RANKL, induced by macrophage colony-stimulating factor, was reduced markedly in D-PDMP-treated cells. d-PDMP also inhibited the phosphorylation of the inhibitor of nuclear factor-kappa B and extracellular signal-regulated kinase 1/2 induced by RANKL. In several experiments with the addition of glycolipids to D-PDMP-treated purified bone marrow cells, lactosylceramide (LacCer) strongly affected the differentiation into tartrate-resistant acid phosphatase mononucleated cells, but not positive multinucleated cells. GM3 and GM1 also recovered, but less effectively compared with LacCer. Moreover, exogenous LacCer recovered the reduced expression of RANK and the phosphorylation of inhibitor of NF-kappa B and extracellular signal-regulated kinase 1/2 after stimulation by RANKL at the same level of cells without D-PDMP treatment. Our data suggest that glycosphingolipids, especially LacCer, are necessary for the initiation step of RANKL-induced osteoclastogenesis.


Assuntos
Antígenos CD , Proteínas de Transporte/fisiologia , Divisão Celular/fisiologia , Lactosilceramidas/fisiologia , Fator Estimulador de Colônias de Macrófagos/fisiologia , Glicoproteínas de Membrana/fisiologia , Osteoclastos/citologia , Animais , Sequência de Bases , Primers do DNA , Masculino , Camundongos , Fosforilação , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B
17.
Int J Radiat Oncol Biol Phys ; 50(2): 301-7, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11380215

RESUMO

PURPOSE: Radiation pneumonitis (RP) is one of the most serious complications for patients who receive thoracic irradiation. To avoid this, early diagnosis of radiation pneumonitis is extremely important. The purpose of the present study is to investigate whether serum pulmonary surfactant proteins A and D (SP-A and SP-D, respectively) could be useful markers for RP. METHODS AND MATERIALS: Eighty-six patients (lung cancer: 42 [primary: 39, metastatic: 3], breast cancer: 23, esophageal cancer: 21) who underwent radiation therapy were prospectively studied. Radiation doses ranged from 30-76 Gy (median, 58 Gy). Serum SP-A and SP-D levels were evaluated sequentially by a sandwich enzyme-linked immunosorbent assay (ELISA) method before, during, and throughout the follow-up period until the development of symptomatic RP or until one year after completion of radiotherapy. Specificity of the ELISA results was confirmed by Western blot analysis. Patients symptomatic for RP were graded according to the Common Toxicity Criteria. RESULTS: RP occurred in 19 patients. Serum SP-D levels of patients with RP were sequentially higher than those in patients without RP. In the monitoring, serum SP-D levels at 50-60 Gy showed greater sensitivity and positive predictive values for RP detection (74% and 68%, respectively) than SP-A (26% and 21%, respectively). Western blot analysis showed that the development of RP was due to overproduction, but not proteolysis of surfactant proteins. CONCLUSION: We confirm that serum SP-A and SP-D monitoring is a practical and useful diagnostic method for the early detection of RP.


Assuntos
Glicoproteínas/sangue , Proteolipídeos/sangue , Surfactantes Pulmonares/sangue , Pneumonite por Radiação/sangue , Pneumonite por Radiação/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Proteína A Associada a Surfactante Pulmonar , Proteína D Associada a Surfactante Pulmonar , Proteínas Associadas a Surfactantes Pulmonares , Sensibilidade e Especificidade , Neoplasias Torácicas/tratamento farmacológico , Neoplasias Torácicas/radioterapia
18.
Arch Oral Biol ; 46(7): 585-92, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11369313

RESUMO

Tooth cementum, a calcified hard tissue covering the root surfaces, is an important component connecting the teeth to the collagenous fibres of the periodontal ligament. Although the overall composition of cementum may closely resemble that of bone, each part has not been fully characterized. Here, the localization of the matrix gamma-carboxyglutamic acid (Gla) protein (MGP), one of the major Gla-containing proteins in the body, in cementum was investigated using immunohistochemistry and in situ hybridization. (1) Strong MGP antigenicity was observed in the acellular cementum, but was only moderate in the cellular cementum; (2) polygonal periodontal ligament cells facing the acellular cementum and the uncalcified cellular cementum expressed MGP mRNA, indicating that these cells produced MGP and deposited it on the cementum; (3) MGP accumulated at the junction between the uncalcified and calcified cellular cementum; and (4) the distribution pattern of MGP antigenicity resembled that of osteopontin. As one function of MGP could be as a negative regulator for mineral apposition, the expression of MGP in the cells adjacent to the cementum may be important to prevent hyperapposition of minerals.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Cemento Dentário/metabolismo , Proteínas da Matriz Extracelular , Calcificação de Dente , Animais , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/genética , Cemento Dentário/anatomia & histologia , Cemento Dentário/química , Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Masculino , Osteocalcina/análise , Osteopontina , Ratos , Ratos Wistar , Sialoglicoproteínas/análise , Proteína de Matriz Gla
19.
Thromb Haemost ; 85(2): 226-30, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11246537

RESUMO

The platelet-collagen receptor, glycoprotein Ia/IIa (integrin alpha2beta1) plays a fundamental role in the adhesion of platelets to fibrillar collagen, an event leading to platelet activation and thrombus formation and contributing to the pathogenesis of thrombotic disease. Further, glycoprotein Ia/IIa receptor density and function may be associated with two linked and silent polymorphisms (807C/T and 873G/A) within the glycoprotein Ia gene. We tested the extent to which these polymorphisms serve as genetic markers of myocardial infarction in a Japanese population. A case-control study was carried out using 210 Japanese myocardial infarction patients and 420 age- and sex-matched controls. Genotyping was accomplished using PCR followed by melting curve analysis with specific fluorescent hybridization probes. The 807CC, CT, TT genotypes linked perfectly to the 873GG, GA, AA genotypes, respectively. Allele frequencies of the 807T (873A) variant were similar in the control and patient groups (0.373 vs. 0.352). The 807T and 873A variants of platelet glycoprotein Ia gene are common and in a perfect linkage in the Japanese population, but it appears unlikely that the 807T (873A) variant represents a useful marker of increased risk for myocardial infarction.


Assuntos
Análise Mutacional de DNA/métodos , Integrinas/genética , Infarto do Miocárdio/genética , Polimorfismo Genético , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Análise Mutacional de DNA/normas , Feminino , Marcadores Genéticos , Genótipo , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Receptores de Colágeno , Fatores de Risco , Fatores Sexuais
20.
Biosci Biotechnol Biochem ; 65(12): 2798-801, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11826982

RESUMO

Transfer RNA is an essential molecule for biological system, and each tRNA molecule commonly has a cloverleaf structure. Previously, we experimentally showed that some Drosophila tRNA (tRNA(Ala), tRNA(His), and tRNA(iMet)) molecules fit to form another, non-cloverleaf, structure in which the 3'-half of the tRNA molecules forms an alternative hairpin, and that the tRNA molecules are internally cleaved by the catalytic RNA of bacterial ribonuclease P (RNase P). Until now, the hyperprocessing reaction of tRNA has only been reported with Drosophila tRNAs. This time, we applied the hyperprocessing reaction to one of human tRNAs, human tyrosine tRNA, and we showed that this tRNA was also hyperprocessed by E. coli RNase P RNA. This tRNA is the first example for hyperprocessed non-Drosophila tRNAs. The results suggest that the hyperprocessing reaction can be a useful tool detect destablized tRNA molecules from any species.


Assuntos
Endorribonucleases/metabolismo , Proteínas de Escherichia coli , Escherichia coli/enzimologia , RNA Catalítico/metabolismo , RNA de Transferência de Tirosina/metabolismo , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Humanos , Hidrólise , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA de Transferência de Tirosina/química , Ribonuclease P
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