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1.
Anaesthesia ; 72(11): 1344-1350, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28805239

RESUMO

We previously demonstrated that the gastric emptying time of different liquids with the same volume mainly depended on their energy content, regardless of differences in composition. In this crossover study, we investigated whether the same applies when soluble solid foods are ingested with water. Ten healthy volunteers ingested one of five test diets consisting of two test meals (Calorie Mate® 100 and 200 kcal) and three test solutions (water and glucose solutions of 100 and 200 kcal), each given in a volume of 400 ml, and then underwent ultrasonography to measure the gastric antral cross-sectional area every 10 min for 120 min. The gastric emptying time was defined as the time for the antral cross-sectional area to revert to its initial value. When test diets with the same energy content were ingested, the gastric emptying curves were nearly identical, regardless of whether the original form was solid or liquid. The median (IQR[range]) gastric emptying times of Calorie Mate® of 100 kcal with water vs. isocaloric glucose solution were 65 (60-78 [50-80]) vs. 65 (60-70 [50-80]) min (p = 0.58), and for Calorie Mate® of 200 kcal with water vs. isocaloric glucose solution they were 100 (93-108 [90-120]) vs. 105 (90-110 [90-120]) min (p = 0.54). The median (IQR [range]) for water was 40 (30-40 [30-50]) min. Energy content may be a critical determinant of the gastric emptying time when ingesting soluble solid diets with water.


Assuntos
Ingestão de Energia , Esvaziamento Gástrico , Refeições , Adulto , Anatomia Transversal , Estudos Cross-Over , Jejum , Alimentos Formulados , Voluntários Saudáveis , Humanos , Masculino , Projetos Piloto , Estômago/diagnóstico por imagem , Ultrassonografia
3.
Br J Anaesth ; 114(1): 77-82, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25260696

RESUMO

BACKGROUND: Although current preoperative fasting guidelines apply restrictions to drinks containing milk because of delayed gastric emptying, the safe volume of milk that can be consumed up to 2 h before surgery on a theoretical basis has not yet been defined. We aimed to determine whether delayed gastric emptying depended mainly on the total amount of calories irrespective of compositional differences between milk and clear fluids. METHODS: We prepared five beverages with a uniform volume (500 ml) and step-wise increments in calories (0, 220, and 330 kcal), comprised mainly of non-human milk, pulpless orange juice, water, and gum syrup. The gastric emptying rate of each beverage was determined by ultrasound measurements of the gastric antral cross-sectional area after their ingestion by eight healthy fasting volunteers. RESULTS: The emptying rates of 500 ml of orange juice and 330 ml of non-human milk with 170 ml of water (both were 220 kcal) from the stomach were similar. Furthermore, 450 ml of orange juice with 50 ml of gum syrup and 500 ml of non-human milk (both were 330 kcal) left the stomach at similar rates. The 220 kcal beverages emptied faster than the 330 kcal beverages. CONCLUSIONS: There were no significant differences in liquid gastric emptying after drinking equal volumes of either orange juice or milk as long as both had the same amount of calories. Liquid gastric emptying depends chiefly on the total caloric content. CLINICAL TRIAL REGISTRATION: UMIN000012537.


Assuntos
Bebidas , Ingestão de Energia/fisiologia , Esvaziamento Gástrico/fisiologia , Adulto , Animais , Humanos , Masculino , Leite , Valores de Referência , Fatores de Tempo , Adulto Jovem
4.
Phys Rev Lett ; 104(14): 147601, 2010 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-20481962

RESUMO

We have investigated the changes occurring in the electronic structure of digitally controlled SrVO(3) ultrathin films across the metal-insulator transition (MIT) by the film thickness using in situ photoemission spectroscopy. With decreasing film thickness, a pseudogap is formed at E(F) through spectral weight transfer from the coherent part to the incoherent part. The pseudogap finally evolves into an energy gap that is indicative of the MIT in a SrVO(3) ultrathin film. The observed spectral behavior is reproduced by layer dynamical-mean-field-theory calculations, and it indicates that the observed MIT is caused by the reduction in the bandwidth due to the dimensional crossover.

5.
J Dent Res ; 89(4): 349-54, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20200412

RESUMO

Indian hedgehog (Ihh) is essential for embryonic mandibular condylar growth and disc primordium formation. To determine whether it regulates those processes during post-natal life, we ablated Ihh in cartilage of neonatal mice and assessed the consequences on temporomandibular joint (TMJ) growth and organization over age. Ihh deficiency caused condylar disorganization and growth retardation and reduced polymorphic cell layer proliferation. Expression of Sox9, Runx2, and Osterix was low, as was that of collagen II, collagen I, and aggrecan, thus altering the fibrocartilaginous nature of the condyle. Though a disc formed, it exhibited morphological defects, partial fusion with the glenoid bone surface, reduced synovial cavity space, and, unexpectedly, higher lubricin expression. Analysis of the data shows, for the first time, that continuous Ihh action is required for completion of post-natal TMJ growth and organization. Lubricin overexpression in mutants may represent a compensatory response to sustain TMJ movement and function.


Assuntos
Cartilagem Articular/crescimento & desenvolvimento , Proteínas Hedgehog/fisiologia , Côndilo Mandibular/crescimento & desenvolvimento , Articulação Temporomandibular/anatomia & histologia , Articulação Temporomandibular/crescimento & desenvolvimento , Agrecanas/biossíntese , Agrecanas/genética , Animais , Anquilose/genética , Anquilose/metabolismo , Cartilagem Articular/anatomia & histologia , Condrócitos/patologia , Colágeno Tipo II/biossíntese , Colágeno Tipo II/genética , Subunidade alfa 1 de Fator de Ligação ao Core/biossíntese , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Regulação para Baixo , Fibrocartilagem/anatomia & histologia , Fibrocartilagem/crescimento & desenvolvimento , Lâmina de Crescimento/anormalidades , Proteínas Hedgehog/genética , Côndilo Mandibular/anatomia & histologia , Camundongos , Camundongos Knockout , Proteoglicanas/biossíntese , Fatores de Transcrição SOX9/biossíntese , Fatores de Transcrição SOX9/genética , Fator de Transcrição Sp7 , Disco da Articulação Temporomandibular/anatomia & histologia , Disco da Articulação Temporomandibular/crescimento & desenvolvimento , Transtornos da Articulação Temporomandibular/genética , Transtornos da Articulação Temporomandibular/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
6.
Allergy ; 65(5): 649-56, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19845571

RESUMO

BACKGROUND: The evaluation of disease severity and activity of chronic urticaria (CU) is essential for the adequate treatment of patients. However, there is no reliable biomarker for such evaluations. Recently, markers of blood coagulation and fibrinolysis have been revealed to be elevated in severe cases of CU. In this article, we studied the coagulation/fibrinolysis and inflammation markers and their relationship to disease activity in patients with CU. METHODS: Plasma fibrin degradation products (FDP), d-dimer and serum C-reactive protein (CRP) were measured with the assessment of disease severity and skin reaction to autologous serum in 82 patients with CU and 37 patients with acute urticaria, idiopathic angioedema (AE) or inducible types of urticaria (IU). RESULTS: The levels of FDP in patients with CU were significantly higher than those in patients with IU, but no other differences in FDP, d-dimer and CRP were observed among patients with different types of urticaria. These markers of patients with CU were well correlated with each other and significantly associated with disease severity of CU, but not with skin reactions to autologous serum. In 37 patients with CU, levels of all these parameters reduced as their disease condition improved, while they increased when the disease became aggravated. Regarding FDP, this relationship was observed even if FDP concentrations were within normal range throughout the study. CONCLUSIONS: The measurement of plasma FDP, d-dimer and serum CRP may be useful for the assessment of disease activity of CU.


Assuntos
Biomarcadores/sangue , Proteína C-Reativa/análise , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Inflamação/sangue , Urticária/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Coagulação Sanguínea/fisiologia , Criança , Pré-Escolar , Doença Crônica , Feminino , Fibrinólise/fisiologia , Humanos , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Testes Cutâneos , Urticária/imunologia , Adulto Jovem
7.
Phys Rev Lett ; 103(1): 012503, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19659141

RESUMO

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

8.
Rheumatology (Oxford) ; 46(11): 1652-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17855425

RESUMO

OBJECTIVES: To find serum markers that may serve as indices for an early diagnosis of degeneration or damage of the articular cartilage. METHODS: Twenty-four healthy volunteers, 19 individuals with knee trauma (KT) and 31 with knee osteoarthritis (OA) were evaluated. KT patients were divided into a group (n = 5) with an injury <2 months old (recent KT) and a group (n = 14) with that >2 months old (old KT). Articular cartilage damage was assessed using either arthroscopy or direct observation. Serum concentrations of hyaluronic acid (HA), cartilage proteoglycan aggrecan turnover epitope (CS846) and cartilage oligomeric protein (COMP) were measured using enzyme-linked immunosorbent assay kits and those of keratan sulfate (KS) and chondroitin-6-sulfate (C6S) using high-performance liquid chromatography. RESULTS: Serum KS in the recent KT group (2095 +/- 594 ng/ml) was significantly higher than that in the old KT group (1373 +/- 418 ng/ml; P = 0.021), and serum COMP in the recent KT group (1572 +/- 182 ng/ml) showed a tendency that was higher than that in the old KT group (1350 +/- 250 ng/ml; P = 0.079). Serum KS in OA patients with Kellgren and Lawrence (KL) grades 0 and I (1456 +/- 334 ng/ml) showed a tendency that was higher than that in OA patients with KL grades II, III and IV (1248 +/- 220 ng/ml; P = 0.084). CONCLUSIONS: The serum concentration of KS correlated with the damage of the articular cartilage and it was significantly increased even at an early stage after the injury.


Assuntos
Doenças das Cartilagens/diagnóstico , Cartilagem Articular/metabolismo , Sulfato de Queratano/sangue , Traumatismos do Joelho/diagnóstico , Osteoartrite do Joelho/diagnóstico , Adulto , Idoso , Artroscopia , Biomarcadores/sangue , Doenças das Cartilagens/diagnóstico por imagem , Proteína de Matriz Oligomérica de Cartilagem , Cartilagem Articular/lesões , Sulfatos de Condroitina/sangue , Proteínas da Matriz Extracelular/sangue , Feminino , Glicoproteínas/sangue , Humanos , Masculino , Proteínas Matrilinas , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Radiografia
9.
Cephalalgia ; 27(9): 1020-3, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17680817

RESUMO

This study examined the clinical picture of probable medication-overuse headache (MOH) and the presence of any features peculiar to Japan. In a retrospective study of 47 patients, type of primary headache, type of medicine overused, method and result of withdrawal were investigated. Among the 47 patients, 80.9% had migraine only, and 85.1% overused combination medications. While 36 patients (76.6%) succeeded in withdrawal, five patients (10.6%) failed. One patient (2.1%) had not improved by 2 months after withdrawal and was diagnosed with chronic migraine and chronic tension-type headache without MOH. The remaining five patients (10.6%) dropped out. All dropout patients were recommended abrupt inpatient withdrawal, but chose abrupt outpatient withdrawal. As features peculiar to Japan, many patients with probable MOH overused combination analgesics, particularly females.


Assuntos
Analgésicos/efeitos adversos , Cefaleia/induzido quimicamente , Cefaleia/epidemiologia , Erros de Medicação/efeitos adversos , Erros de Medicação/estatística & dados numéricos , Medição de Risco/métodos , Adulto , Idoso , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco
10.
Poult Sci ; 86(6): 1166-73, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17495088

RESUMO

The levels of mRNA expression in regulatory genes that are involved in the pathological changes of aortic atherosclerotic and fibroblastic intimal thickening was investigated in Japanese quail. The quail were divided into a control diet group and an atherogenic diet group. The quail were euthanized at 2, 4, 8, and 12 wk after consuming either a control diet or an atherogenic diet. Thereafter, both histological and immunohistochemical studies and mRNA expression analysis of the cell-cycle-regulating genes in aortic atherosclerotic lesions were performed on selected ascending aortas and their large branches. In the atherogenic diet group, aortic lipid-containing intimal and atheromatous lesions were seen mainly at 8 and 12 wk, respectively. Semiquantitative reverse-transcription PCR was used to analyze the alterations of mRNA expression on the development of atherosclerotic lesions. Messenger RNA expression of the c-fos and c-src genes showed peak levels at 8 wk in the atherogenic diet group. However, no significant alteration of c-jun mRNA expression was noted during the entire experimental period. According to the progression of aortic atherosclerotic lesions, c-myc mRNA expression in the atherogenic diet group increased chronologically, and the highest level was observed at 12 wk. Alterations in mRNA expression of proliferating cell nuclear antigen and the p27 gene were similar to that of c-myc. The levels of c-myc, proliferating cell nuclear antigen, and p27 mRNA expression was significantly correlated with the degree of aortic atherosclerotic lesion development at 12 wk in our experiment.


Assuntos
Aterosclerose/veterinária , Coturnix/genética , Gorduras na Dieta/farmacologia , Regulação da Expressão Gênica/genética , Genes cdc , Doenças das Aves Domésticas/genética , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Peso Corporal , Dieta/veterinária , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Doenças das Aves Domésticas/induzido quimicamente , RNA Mensageiro/metabolismo
11.
J Dent Res ; 86(5): 469-74, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17452570

RESUMO

While dental pulp appears to be able to form mineralized matrices that do not always resemble dentin, the precise characteristics of the hard tissue and the mechanism of its induction remain unknown. Therefore, we evaluated hard tissue induced by transplantation of pulp into subcutaneous tissue. Seven days after transplantation, initial hard tissue was formed at the inner periphery of the pulp. After 14 days, this hard tissue expanded inwardly. Mineralized matrix was immunopositive for osteocalcin, osteopontin, and bone sialoprotein, but negative for dentin sialoprotein. Transplantation of GFP-labeled pulp into wild-type rats showed these formative cells to have been derived from the transplant. TEM observation revealed apatite crystals within necrotic cells and matrix vesicles at the initial stage of calcification. These results indicate that pulp cells possess the ability to form a bone- or cementum-like matrix. Calcification of the matrix may occur in necrotic cells and matrix vesicles, followed by collagenous calcification.


Assuntos
Calcificações da Polpa Dentária/metabolismo , Polpa Dentária/metabolismo , Polpa Dentária/transplante , Animais , Animais Geneticamente Modificados , Polpa Dentária/química , Proteínas da Matriz Extracelular/análise , Proteínas de Fluorescência Verde , Imuno-Histoquímica , Sialoproteína de Ligação à Integrina , Masculino , Microscopia Eletrônica de Transmissão , Osteocalcina/análise , Osteopontina/análise , Fosfoproteínas , Precursores de Proteínas/análise , Ratos , Sialoglicoproteínas/análise , Tela Subcutânea
12.
Eur J Med Res ; 12(1): 43-6, 2007 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-17363357

RESUMO

Bacteremia due to Mycobacterium abscessus, a rapid grower, belonging to the Runyon group IV, occurred in an inpatient with fever of unidentified origin in Shinshu University Hospital. To the best of our knowledge, this is the first documented case of M. abscessus bacteremia in Japan. The organism initially grew on Sheep blood agar plates after terminal-subculturing from the BacT/Alert SA aerobic blood culture bottles with no positive signal, and was subsequently identified as M. abscessus using 16S rRNA sequence analysis. We evaluated the BacT/Alert SA bottles for the detection of Mycobacterium species, with special reference to the rapid growers including M. abscessus by seeding experiments and obtained the following findings: 1) The BacT/Alert system shows the positive sign when the bacterial cell counts reach around 10(6) to 10(7) CFU/ml. 2) The System requires around 6 to 7 days of incubation to obtain a sufficient bacterial growth for the positive signal. 3) The System may result in false negative under the 5-day-culture method recommended by American Society for Microbiology in cases of using automated blood culture systems. 4) So-called the blind- or terminal-subcultures from the bottles are inevitable to perform for precluding the false negative cases.


Assuntos
Bacteriemia/diagnóstico , Técnicas Bacteriológicas , Sangue/microbiologia , Mycobacterium/genética , Bacteriemia/microbiologia , Meios de Cultura , Estudos de Avaliação como Assunto , Humanos , Mycobacterium/crescimento & desenvolvimento , Especificidade da Espécie
13.
J Biomed Mater Res B Appl Biomater ; 83(2): 327-31, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17385227

RESUMO

We assessed the biological response to several novel titanium alloys that have promising physical properties for biomedical applications. Four commercial titanium alloys [Super-TIX(R) 800, Super-TIX(R) 51AF, TIMETAL(R) 21SRx, and Ti-6Al-4V (ASTM grade 5)] and three experimental titanium alloys [Ti-13Cr-3Cu, Ti-1.5Si and Ti-1.5Si-5Cu] were tested. Specimens (n = 6; 5.0 x 5.0 x 3.0 mm(3)) were cast in a centrifugal casting machine using a MgO-based investment and polished to 600 grit, removing 250 mum from each surface. Commercially pure titanium (CP Ti: ASTM grade 2) and Teflon (polytetrafluoroethylene) were used as positive controls. The specimens were cleaned and disinfected, and then each cleaned specimen was placed in direct contact with Balb/c 3T3 fibroblasts for 72 h. The cytotoxicity [succinic dehydrogenase (SDH) activity] of the extracts was assessed using the MTT method. Cytotoxicity of the metals tested was not statistically different compared to the CP Ti and Teflon controls (p > 0.05). These novel titanium alloys pose cytotoxic risks no greater than many other commonly used alloys, including commercially pure titanium. The promising short-term biocompatibility of these Ti alloys is probably due to their excellent corrosion resistance under static conditions, even in biological environments.


Assuntos
Ligas/toxicidade , Materiais Biocompatíveis/toxicidade , Fibroblastos/efeitos dos fármacos , Titânio/toxicidade , Animais , Células 3T3 BALB , Teste de Materiais , Camundongos
14.
Br J Surg ; 93(3): 339-46, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16498606

RESUMO

BACKGROUND: There is no standard method for predicting remnant liver functional reserve after hepatectomy or for monitoring it in real time. METHODS: Indocyanine green (ICG) clearance (K) was measured non-invasively and instantaneously using pulse spectrophotometry before surgery, during inflow occlusion and after hepatectomy in 75 patients who underwent anatomical liver resection for hepatocellular carcinoma (HCC). RESULTS: Eight patients (11 per cent) suffered liver failure and one (1 per cent) died in hospital. An estimated remnant K value of 0.090 per min was the cut-off value for liver failure. In a logistic regression model, the estimated remnant K (0.090 per min; P = 0.022) and age (65 years; P = 0.025) were significant predictors of postoperative liver failure. There was a correlation between the estimated and measured post-hepatectomy K, and between the inflow occlusion K and measured post-hepatectomy K (P < 0.001). The cut-off value of less than 0.090 per min for the estimated remnant K resulted in 88 per cent sensitivity and 82 per cent specificity for predicting liver failure. CONCLUSION: Perioperative real-time monitoring of ICG-K is useful for evaluating the remnant liver functional reserve before, during and after liver resection for HCC. The estimated remnant K is a significant predictor of liver failure.


Assuntos
Carcinoma Hepatocelular/cirurgia , Falência Hepática/etiologia , Neoplasias Hepáticas/cirurgia , Fígado/irrigação sanguínea , Espectrofotometria/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/irrigação sanguínea , Corantes , Feminino , Hepatectomia/métodos , Humanos , Verde de Indocianina , Falência Hepática/diagnóstico , Neoplasias Hepáticas/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
15.
Dig Liver Dis ; 37(12): 968-72, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16243012

RESUMO

Inflammatory fibroid polyp is a rare benign polypoid lesion of the gastrointestinal tract. Histologically, inflammatory fibroid polyp is characterised by an admixture of numerous small vessels, fibroblasts and oedematous connective tissue, accompanied by marked inflammatory infiltration by eosinophils. A 40-year-old man visited our hospital for the purpose of colorectal screening due to a positive faecal occult blood test. A pedunculated and reddish polyp was found endoscopically in the ascending colon. The polyp was large but was resected endoscopically without any problems. Histologically, the abnormal tissue of the polyp was located in the submucosal and mucosal layer. Proliferation of spindle cells and infiltration of inflammatory cells, such as plasma cells and eosinophils, were observed. Immunohistochemically, the spindle cells were positive for CD34, which was localised in the cytoplasm. These cells were also positive for S100 protein but were negative for c-kit and muscle markers. These findings are compatible with the histological diagnosis of inflammatory fibroid polyp. The surgical margin of the polyp was free of the tumour. Inflammatory fibroid polyp is more commonly found in the stomach or small intestine, and rarely in the colon, and therefore our case is a rare example of large and pedunculated colonic inflammatory fibroid polyp, which was treated successfully by endoscopic polypectomy.


Assuntos
Pólipos do Colo/cirurgia , Colonoscopia , Sangue Oculto , Adulto , Pólipos do Colo/diagnóstico , Humanos , Masculino , Instrumentos Cirúrgicos
16.
J Exp Clin Cancer Res ; 24(1): 75-82, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15943035

RESUMO

The aim of the present study was to determine whether expression of the CD44 variant v7-v8 (CD44v7-v8) or vascular endothelial growth factor-C (VEGF-C) is associated with long-term prognosis in breast cancer patients. A 10-year follow-up of 91 patients with primary breast cancer who were previously assessed for CD44 expression was undertaken. Immunohistochemical evaluation of VEGF-C expression was performed in 87 of these patients and their long-term prognosis was assessed. The disease-free and overall survival rates were significantly poorer for the CD44v7-v8-positive patients than for the patients negative for this marker. VEGF-C expression was detected in 38 out of the 87 patients (43.7%) with primary human breast cancer. There were no significant differences in tumor size, histological type, axillary lymph node status, presence of lymphatic or venous invasion, or presence of estrogen receptors and progesterone receptors between the VEGF-C-positive and -negative patients. There were also no significant differences in the disease-free or overall survival rates in these patient groups. In conclusion after the 10-year follow-up, expression of CD44v7-v8 was associated with poor prognosis for breast cancer patients. However, there was no association between VEGF-C expression and the clinicopathological factors or prognosis of breast cancer patients.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Variação Genética/genética , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Metástase Linfática , Fator C de Crescimento do Endotélio Vascular/metabolismo , Neoplasias da Mama/genética , Intervalo Livre de Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Mutação/genética , Prognóstico , Taxa de Sobrevida , Fatores de Tempo
17.
Acta Biomater ; 1(3): 353-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16701813

RESUMO

This study characterized the electrochemical behavior of Ti-Hf binary alloys in a simulated oral environment. Ti-Hf alloys (10, 20, 25, 30, 35 and 40 mass% Hf) were prepared by arc-melting titanium sponge and hafnium sponge. Specimens of each alloy (n = 4) were prepared using a dental titanium casting system with a MgO-based investment. Specimens were inspected with X-ray radiography to ensure minimal internal porosity. Castings (n = 4) made from pure titanium and commercially pure titanium were used as controls. The ground flat surface (10 mm x 10 mm) on each specimen where approximately 30 microm was removed was used for the characterization. Sixteen-hour open-circuit potential (OCP) measurement, linear polarization and potentiodynamic cathodic polarization were performed sequentially in aerated (air + 10% CO2) MTZ synthetic saliva at 37 degrees C. Potentiodynamic anodic polarization was conducted in the same medium but deaerated (N2 + 10% CO2) 2 h before and during testing. Polarization resistance (R(P)) and Tafel slopes were determined, as were corrosion current density (I(CORR)) and passive current density (I(PASS)). Results were subjected to nonparametric statistical analysis (alpha = 0.05). The OCP stabilized (mean values -229 mV to -470 mV vs. SCE) for all specimens after the 16-h immersion. Similar passivation was observed for all the metals on their anodic polarization diagrams. The Kruskal-Wallis test showed significant differences in OCP among the test groups (p = 0.006). No significant differences were found in R(P), I(CORR) or I(PASS) among all the metals (p>0.3). Results indicate that the electrochemical behavior of the Ti-Hf alloys examined resembles that of pure titanium.


Assuntos
Ligas , Háfnio/química , Titânio/química , Eletroquímica
18.
J Oral Rehabil ; 31(11): 1109-14, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15525390

RESUMO

The mechanical properties of Ti-6Al-4V-XCu (1, 4 and 10 wt% Cu) alloys were examined. The castings for each alloy were made in a centrifugal titanium casting machine. Two shapes of specimens were used: a dumbbell (20 mm gauge length x 2.8 mm diameter) for mechanical property studies, and a flat slab (2 mm x 10 mm x 10 mm) for metallography, microhardness determination and X-ray diffractometry. Tensile strength, yield strength, modulus of elasticity, elongation and microhardness were evaluated. After tensile testing, the fracture surfaces were observed using scanning electron microscopy. The tensile strengths of the quaternary alloys decreased from 1016 MPa for the 1% Cu alloy to 387 MPa for the 10% Cu alloy. Elongation decreased with an increase in the copper content. The 1% Cu alloy exhibited elongation similar to Ti-6Al-4V without copper (3.0%). The results also indicated that the copper additions increased the bulk hardness of the quaternary alloy. In particular, the 10% Cu alloy had the highest hardness and underwent the most brittle fracture. The mechanical properties of cast Ti-6Al-4V alloy with 1 and 4% Cu were well within the values for existing dental casting non-precious alloys.


Assuntos
Ligas , Cobre , Titânio , Técnica de Fundição Odontológica , Dureza , Teste de Materiais , Microscopia Eletrônica de Varredura , Resistência à Tração
19.
J Oral Rehabil ; 31(2): 185-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15009605

RESUMO

Titanium-based alloys form a surface reaction layer when cast. This study investigated the effect of the surface reaction layer on the cytotoxicity of novel Ti-based binary alloys. The cytotoxicities of the novel alloys were compared with commercially pure titanium, Ti-6Al-4V and Ti-6Al-7Nb. Cast discs with or without the reaction layer were first tested for cytotoxicity, then for elemental release into cell-culture medium. The elements released into the extracts were measured by means of an inductively coupled plasma atomic emission spectrometer. The commercial and novel binary Ti-based alloys showed no statistically significant cytotoxicity, although some trends were noted for several alloys. The presence of the reaction layer did not significantly alter the cytotoxicity. These favourable biocompatibility results show that these novel alloys have promise for use in dental restorations.


Assuntos
Ligas/efeitos adversos , Titânio/efeitos adversos , Animais , Células Cultivadas , Restauração Dentária Permanente , Fibroblastos/efeitos dos fármacos , Espectrometria de Massas/métodos , Teste de Materiais/métodos , Camundongos , Camundongos Endogâmicos BALB C , Succinato Desidrogenase/metabolismo , Propriedades de Superfície
20.
Biomaterials ; 25(16): 3147-53, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14980409

RESUMO

This study examined the Hg evaporation during setting from experimental Ag-Sn-Cu alloy powders with and without Pd. Four series of alloy powders were fabricated to examine the effect on the Hg evaporation of the alloy compositions (all percentages in this report are weight percents): Pd (0-1.5), Cu (9.0-14.0), Ag (57.0-63.7), and Sn (24.9-29.5). These variations in composition produced alloy powders with gamma-Ag3Sn to beta-AgSn ratios varying from 0.0 to 23.9. The total amounts of Hg released from 10 min after trituration were measured from cylindrical specimens (4 x 8mm; n = 4 ) at 37 degrees C using a Hg vapor analyzer. The results were compared to those from commercial alloys (one high-Cu and one low-Cu alloy). All amalgams made from alloys containing 1.5% Pd exhibited lower Hg vapor release than any other amalgams, with the exception of the low-Cu amalgam. The results clearly showed that the alloy formulation affected the mercury evaporation behavior during setting of the resultant amalgams. A small addition of Pd to the alloy can produce amalgams with 50-60% less Hg vapor release during setting than a leading commercial high-Cu amalgam, Tytin.


Assuntos
Amálgama Dentário/química , Teste de Materiais , Mercúrio/química , Paládio/química , Cobre/química , Projetos Piloto , Pós , Prata/química , Estanho/química , Volatilização
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