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1.
Br J Cancer ; 110(1): 156-63, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24253505

RESUMO

BACKGROUND: Transforming growth factor-ß (TGF-ß) is a major inducer of epithelial-mesenchymal transition (EMT) in different cell types. TGF-ß-mediated EMT is thought to contribute to tumour cell spread and metastasis. Sialyl Lewis antigens synthesised by fucosyltransferase (FUT) 3 and FUT6 are highly expressed in patients with metastatic colorectal cancer (CRC) and are utilised as tumour markers for cancer detection and evaluation of treatment efficacy. However, the role of FUT3 and FUT6 in augmenting the malignant potential of CRC induced by TGF-ß is unclear. METHODS: Colorectal cancer cell lines were transfected with siRNAs for FUT3/6 and were examined by cell proliferation, invasion and migration assays. The expression and phosphorylation status of TGF-ß downstream molecules were analysed by western blot. Fucosylation of TGF-ß receptor (TßR) was examined by lectin blot analysis. RESULTS: Inhibition of FUT3/6 expression by siRNAs suppressed the fucosylation of type I TßR and phosphorylation of the downstream molecules, thereby inhibiting the invasion and migration of CRC cells by EMT. CONCLUSION: Fucosyltransferase 3/6 has an essential role in cancer cell adhesion to endothelial cells by upregulation of sialyl Lewis antigens and also by enhancement of cancer cell migration through TGF-ß-mediated EMT.


Assuntos
Neoplasias Colorretais/metabolismo , Fucosiltransferases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Fucosiltransferases/genética , Células HT29 , Humanos , Fosforilação , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Transdução de Sinais , Proteínas Smad/metabolismo , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Regulação para Cima
2.
Blood Cancer J ; 2: e87, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22961059

RESUMO

Aberrant reactivation of hedgehog (Hh) signaling has been described in a wide variety of human cancers including cancer stem cells. However, involvement of the Hh-signaling system in the bone marrow (BM) microenvironment during the development of myeloid neoplasms is unknown. In this study, we assessed the expression of Hh-related genes in primary human CD34(+) cells, CD34(+) blastic cells and BM stromal cells. Both Indian Hh (Ihh) and its signal transducer, smoothened (SMO), were expressed in CD34(+) acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)-derived cells. However, Ihh expression was relatively low in BM stromal cells. Remarkably, expression of the intrinsic Hh-signaling inhibitor, human Hh-interacting protein (HHIP) in AML/MDS-derived stromal cells was markedly lower than in healthy donor-derived stromal cells. Moreover, HHIP expression levels in BM stromal cells highly correlated with their supporting activity for SMO(+) leukemic cells. Knockdown of HHIP gene in stromal cells increased their supporting activity although control cells marginally supported SMO(+) leukemic cell proliferation. The demethylating agent, 5-aza-2'-deoxycytidine rescued HHIP expression via demethylation of HHIP gene and reduced the leukemic cell-supporting activity of AML/MDS-derived stromal cells. This indicates that suppression of stromal HHIP could be associated with the proliferation of AML/MDS cells.

3.
Osteoarthritis Cartilage ; 20(11): 1383-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22846714

RESUMO

OBJECTIVE: Previous studies have shown that meniscectomy results in an increase of local load transmission and may cause degeneration of the knee cartilage. Using 3D reconstructed T2 mapping, we examined the influence on the femoral cartilage under loading after medial meniscectomy. DESIGN: Ten porcine knees were imaged using a pressure device and a 3.0-T magnetic resonance imaging (MRI) system. Consecutive sagittal T2 maps were obtained in neutral alignment with and without compression, and under compression at 10° varus alignment. After medial meniscectomy, the aforementioned MRI was repeated. Cartilage T2 before and after meniscectomy under each condition were compared at the 12 regions of interest (ROIs) defined on the 3D weight-bearing area of the femoral cartilage. RESULTS: Before meniscectomy, large decreases in T2 under neutral compression were mainly seen at the anterior and central ROIs of the medial cartilage, which shifted to the posterior ROIs after meniscectomy. There were significant differences in decrease in T2 ratio with loading before and after meniscectomy (9.8%/4.3% at the anterior zone, 4.0%/11.4% at the posterior zone, P < 0.05). By applying varus compression, a more remarkable decrease in the cartilage T2 in posterior ROIs after meniscectomy was achieved. (Before/after meniscectomy: 8.7%/2.5% at the anterior zone, 7.2%/18.7% at the posterior zone, P < 0.05). CONCLUSIONS: Assuming a decrease in T2 with loading correlated with the applied pressure, a deficiency of the medial meniscus resulted in a shift of the primary area with a maximal decrease of cartilage T2 with loading posteriorly in the porcine knee joint, presumably reflecting the intraarticular environment of load transmission.


Assuntos
Artroscopia/efeitos adversos , Cartilagem Articular/patologia , Meniscos Tibiais/cirurgia , Joelho de Quadrúpedes/patologia , Animais , Cartilagem Articular/fisiopatologia , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Meniscos Tibiais/fisiopatologia , Joelho de Quadrúpedes/fisiopatologia , Joelho de Quadrúpedes/cirurgia , Suínos , Suporte de Carga
4.
Osteoarthritis Cartilage ; 20(7): 646-52, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22469852

RESUMO

OBJECTIVE: The purpose of this study was to examine the three-dimensional (3D) progression patterns of early acetabular cartilage damage in hip dysplasia using high-resolutional computed tomography (CT) arthrography. DESIGN: Thirty-two dysplastic hips of 26 Japanese symptomatic females including 21 hips in pre-stage of osteoarthritis (Kellgren-Lawrence (K-L) grade 0; mean patient age, 32.0 years) and 11 hips in early stage of osteoarthritis (K-L grade 1 or 2; mean patient age, 32.8 years) were examined. Isotropic high-resolutional CT arthrography with an image resolution of 0.5 mm in any orthogonal direction was performed. A 3D acetabular cartilage model was generated and we evaluated distribution of cartilage thickness in 12 zones after dividing the weight-bearing area of the hip joint in radial and lateral/medial directions. RESULTS: In pre-stage of osteoarthritis, significant differences in cartilage thickness were observed between the lateral and medial zones in all radial regions, most prominently in the antero-superior region. In early stage of osteoarthritis, no significant differences in cartilage thickness were observed, except in the most posterior region. The lateral-medial (LM) ratio was defined as cartilage thickness in the lateral zone divided by that in the medial zone, and hips with the LM ratio in the antero-superior region of <1.4 had significantly more extensive involvement of labral tears than hips with the LM ratio of ≥1.4. CONCLUSIONS: In hip dysplasia, acetabular cartilage damage was probably occurred in the antero-superior lateral area. The LM ratio may be a sensitive index to quantify early cartilage damage associated with extent of labral disorders.


Assuntos
Acetábulo/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Luxação Congênita de Quadril/complicações , Osteoartrite do Quadril/etiologia , Acetábulo/patologia , Adolescente , Adulto , Artrografia/métodos , Cartilagem Articular/patologia , Diagnóstico Precoce , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Pessoa de Meia-Idade , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
5.
Br J Radiol ; 83(990): 509-14, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20505032

RESUMO

Our aim was to assess the protective effect of hydrogen-rich water against cisplatin-induced nephrotoxicity in rats using dynamic contrast-enhanced CT (DCE-CT). DCE-CT studies were performed in 30 rats (8 weeks old) on days 0, 2, 4 and 7 using multidetector row CT. The rats were divided into three groups: a control group (n = 6) with free access to standard water and without cisplatin injection, a non-treatment group (n = 12) with free access to standard water and injected with cisplatin (3.6 mg kg(-1) body weight) intraperitoneally on day 0 and a treatment group (n = 12) with free access to hydrogen-rich water starting from 7 days before cisplatin injection. The contrast clearance per unit renal volume (K(1)) was estimated from the DCE-CT data using the Patlak model. The contrast clearance of the entire kidney (K) was obtained by multiplying K(1) by the renal volume. The serum creatinine level was also measured on day 7. The K(1) and K values normalised by those on day 0 in the treatment group were significantly greater than those in the non-treatment group on days 2, 4 and 7. There were no significant differences in the normalised K value between the treatment and control groups on days 2 and 7. The serum creatinine level in the treatment group was significantly lower than that in the non-treatment group and was not significantly different from that in the control group. This study demonstrated that hydrogen-rich water ameliorates renal dysfunction due to cisplatin-induced nephrotoxicity in rats.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Hidrogênio/farmacologia , Rim/efeitos dos fármacos , Animais , Estudos de Casos e Controles , Meios de Contraste , Creatinina/sangue , Modelos Animais de Doenças , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X/métodos , Água
6.
J Med Eng Technol ; 33(6): 460-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19479608

RESUMO

This study was undertaken to develop a method to quantitatively monitor the effect of inhibition of nitric oxide synthase (NOS) on tumour vascular activity using dynamic contrast-enhanced computed tomography (DCE-CT). The DCE-CT studies were performed in 13 anaesthetized rats bearing tumours. To investigate the effect of NOS inhibition, N-nitro-L-arginine (L-NNA) was intravenously administered in eight rats, while only the vehicle was administered in five rats. The contrast enhancement (CE) images were generated by subtracting the CT images before and after the administration of contrast agent. The tumour blood volume (TBV) images were also generated. The CE significantly decreased after L-NNA administration, while there were no significant changes when only the vehicle was administered. There was a good correlation between CE and TBV, suggesting that CE mainly reflects TBV. In conclusion, the present method appears to be useful for monitoring the effect of NOS inhibition on tumour vascular activity.


Assuntos
Volume Sanguíneo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Neoplasias/irrigação sanguínea , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/farmacologia , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Animais , Masculino , Ratos , Ratos Endogâmicos F344
7.
Br J Radiol ; 82(978): 504-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19153183

RESUMO

It is useful to utilise a computed radiography system with a combination of storage phosphor plates and therapy cassettes for portal images. However, the therapy cassette has some disadvantages. The objective of the present study was to determine whether the disadvantages of a diagnostic cassette could be overcome to obtain clinically useful portal images. A storage phosphor plate has 0.3 mm of lead foil on the distal surface to reduce backscattered radiation. When the plate is reversed, the lead foil acts as a front intensifying screen, similar to the metal plate of a therapy cassette. We reversed a combination of the diagnostic cassette and storage phosphor plate and obtained portal images of the contrast-detail phantom and the Rando phantom (The Phantom Laboratory, Salem, NY) using three types of cassettes: a reversed diagnostic cassette, a therapy cassette and a diagnostic cassette. The image quality was subjectively evaluated. The Friedman and Wilcoxon tests were applied for statistical analyses. Evaluation of images for the contrast-detail phantom revealed that the reversed diagnostic cassette was inferior to the therapy cassette and superior to the diagnostic cassette, and that the differences were significant (p<0.017). There was no significant difference between the reversed diagnostic cassette and therapy cassette (p>0.05) for the Rando phantom. Portal images obtained using the reversed diagnostic cassette were of sufficiently high quality for clinical use as determined by Rando phantom studies.


Assuntos
Aumento da Imagem/instrumentação , Fósforo , Ecrans Intensificadores para Raios X/normas , Desenho de Equipamento/métodos , Humanos , Imagens de Fantasmas
8.
Br J Radiol ; 81(970): 790-800, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18591199

RESUMO

The purpose of this study was to investigate the accuracy of a quantitative method for estimating arterial hepatic blood flow and portal hepatic blood flow separately using a dual-input single-compartment model compared with the maximum slope method using computer simulations and clinical data. In computer simulations, the rate constants for the transfer of contrast agent (CA) from the hepatic artery to the liver (K(1a)), from the portal vein to the liver (K(1p)) and from the liver to the blood (k(2)) were estimated from simulated time-density curves with various transit times of CA from the aorta to the liver (tau(a)) and from the portal vein to the liver (tau(p)) using the linear least-squares (LLSQ) method. In clinical studies, dynamic CT data were acquired from 27 patients, and parametric maps of K(1a), K(1p) and k(2) were generated by applying the LLSQ method pixel by pixel. In simulation studies, tau(a) and tau(p) were found to have a large and a small effect on the estimates of K(1a) and K(1p), respectively. In clinical studies, the K(1a) and K(1p) values estimated with the maximum slope method were underestimated by 60+/-29% and 37+/-12%, respectively, compared with those estimated by the LLSQ method. In conclusion, our results suggest that correction of tau(a) is necessary for accurately estimating K(1a) and K(1p). Our method is therefore promising for the evaluation of hepatic blood flow in various liver diseases because it allows us to evaluate arterial hepatic blood flow and portal hepatic blood flow separately and visually.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Artéria Hepática/fisiopatologia , Circulação Hepática/fisiologia , Neoplasias Hepáticas/irrigação sanguínea , Fígado/irrigação sanguínea , Veia Porta/fisiopatologia , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/secundário , Simulação por Computador , Meios de Contraste , Feminino , Humanos , Fígado/diagnóstico por imagem , Hepatopatias/fisiopatologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
9.
J Orthop Surg (Hong Kong) ; 15(1): 22-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17429112

RESUMO

PURPOSE: To assess the biomechanical and histological effects of a high-voltage electrical field on ligament healing. METHODS: 54 male Wistar rats were used. The medial collateral ligaments (MCLs) of 6 rats were measured for normal biomechanical failure load and stiffness. MCLs of the remaining 48 rats were transected and randomly assigned; half were subjected to a high-voltage electrical field for 8 hours a day (experimental group), and the other half were kept under normal conditions (control group). Eight rats from each group were killed 2, 4, and 6 weeks after the transection and their MCLs were tested biomechanically and histologically. RESULTS: Failure load and stiffness of the MCLs in the experimental group were significantly higher than those in the control group 2 weeks after transection, but not thereafter. At week 2, the granulation tissue completely occupied the space between the cut ends of the MCL in the experimental group, whereas some gaps remained in the control group. CONCLUSION: A high-voltage electrical field appear to accelerate ligament healing in the initial 2 weeks. Earlier initial healing may allow earlier start of the rehabilitation.


Assuntos
Terapia por Estimulação Elétrica , Membro Posterior/lesões , Ligamentos Articulares/lesões , Cicatrização , Animais , Fenômenos Biomecânicos , Colágeno Tipo I/metabolismo , Tecido de Granulação/patologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
10.
Br J Radiol ; 78(930): 519-27, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15900057

RESUMO

The purpose of this study was to evaluate the clinical efficacy of flexible noise control (FNC) image processing in off-line computed radiography (CR) portal images. An observer study was designed to compare FNC with multiobjective frequency processing (MFP) in images acquired using a CR portal imaging device (CRPID). The image processing of MFP and FNC used the same data and required no additional irradiation of patients, and all images were printed on 10-bit grey-level dry laser film. Four radiation technologists and one oncologist served as observers and evaluated 40 sets of images for three different treatment sites: brain, lung and pelvis. Six to 10 anatomical landmarks were selected from each treatment site. Each observer was asked to rate each landmark in terms of its clinical visibility and rate the ease of making the pertinent verification in the MFP- and FNC-processed images. In the ratings of the visibility of landmarks and for the verification of treatment ports, FNC-processed images were more visible than MFP-processed images except for several landmarks in the anteroposterior (AP) pelvis such as the pubic symphysis. The visibility of landmarks in FNC-processed images was comparable with that in MFP-processed images. The verification of treatment ports using the CRPID with FNC was generally achievable. In conclusion, this study suggests that FNC is effective for image processing of CR portal images.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Artefatos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Neoplasias/radioterapia , Neoplasias Pélvicas/diagnóstico por imagem , Neoplasias Pélvicas/radioterapia , Tomografia Computadorizada por Raios X/instrumentação
11.
J Int Med Res ; 31(2): 69-75, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12760309

RESUMO

Interleukin 6 (IL-6) is a pleiotropic cytokine with many physiological functions. The present study was designed to determine the expression of IL-6 and its receptor (IL-6R) in human gastric and colorectal cancers. Nine gastric- and nine colorectal cancer cell lines were analysed. The IL-6 gene was expressed in two gastric cancer cell lines and one colorectal cancer cell line; however, most of the cancer cell lines studied expressed the IL-6R gene. The level of IL-6 secretion in the gastric cancer cell lines correlated with the level of soluble IL-6R secretion, and was significantly higher (< approximately 100 pg/ml) than the level of IL-6 secretion in the colorectal cancer cell lines (< approximately 50 pg/ml). These results suggest that IL-6 may act in a paracrine fashion rather than an autocrine fashion in these cell lines.


Assuntos
Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Interleucina-6/metabolismo , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Humanos , Neoplasias Gástricas/genética
12.
IEEE Trans Neural Netw ; 14(4): 820-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-18238062

RESUMO

Presents a constructive algorithm for training cooperative neural-network ensembles (CNNEs). CNNE combines ensemble architecture design with cooperative training for individual neural networks (NNs) in ensembles. Unlike most previous studies on training ensembles, CNNE puts emphasis on both accuracy and diversity among individual NNs in an ensemble. In order to maintain accuracy among individual NNs, the number of hidden nodes in individual NNs are also determined by a constructive approach. Incremental training based on negative correlation is used in CNNE to train individual NNs for different numbers of training epochs. The use of negative correlation learning and different training epochs for training individual NNs reflect CNNEs emphasis on diversity among individual NNs in an ensemble. CNNE has been tested extensively on a number of benchmark problems in machine learning and neural networks, including Australian credit card assessment, breast cancer, diabetes, glass, heart disease, letter recognition, soybean, and Mackey-Glass time series prediction problems. The experimental results show that CNNE can produce NN ensembles with good generalization ability.

13.
Hepatogastroenterology ; 49(45): 639-43, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12063959

RESUMO

BACKGROUND/AIMS: Recent studies have shown that focal active gastritis seems to be the typical gastric pathology in Crohn's disease. The aim of this study was to compare the incidence of focal active gastritis, Helicobacter pylori infection and distribution of gastric mast cells and macrophages in patients with Crohn's disease, ulcerative colitis and H. pylori gastritis without inflammatory bowel disease. METHODOLOGY: Patients with histologically confirmed Crohn's disease (n = 25) or ulcerative colitis (n = 25) and control patients without inflammatory bowel disease (n = 25) were included in this study. Biopsy specimens were obtained from the antrum and corpus of each patient, and stained with hematoxylin and eosin and immunostained using antibodies to tryptase (AA1) and CD68. The number of mast cells and macrophages located in the lamina propria was determined. RESULTS: Focal active gastritis was detected in 54% of H. pylori-negative patients with Crohn's disease, but it was not found in patients with ulcerative colitis nor in the control group. The density of mast cells and macrophages in the lamina propria of H. pylori-positive patients was significantly higher than in H. pylori-negative patients in all groups. In the Crohn's disease group, the number of mast cells (antrum; 83 +/- 11, body; 89 +/- 11/mm2) and macrophages (antrum; 94 +/- 22, body; 92 +/- 17/mm2) in the lamina propria of H. pylori-negative patients with focal active gastritis was halfway between that in H. pylori-positive and H. pylori-negative patients. In focal active gastritis, mast cells accumulated at the border of focal active gastritis, whereas macrophages accumulated in the center of such lesions. CONCLUSIONS: Our findings indicated that the diagnosis of focal active gastritis, using immunostain for mast cells and macrophages, is the histological hallmark of gastric Crohn's disease. Macrophages might be associated with the formation of focal active gastritis in patients with Crohn's disease.


Assuntos
Doença de Crohn/patologia , Gastrite/patologia , Helicobacter pylori , Macrófagos/patologia , Mastócitos/patologia , Adulto , Colite Ulcerativa/patologia , Doença de Crohn/complicações , Infecções por Helicobacter/complicações , Infecções por Helicobacter/patologia , Humanos , Imuno-Histoquímica
16.
Eur J Nucl Med ; 28(11): 1640-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702105

RESUMO

We previously developed an alternative method for estimating the brain perfusion index (BPI) using technetium-99m compounds and spectral analysis (SA) for quantification of cerebral blood flow (CBF). In this study, we investigated the reproducibility of the BPI values obtained by SA (BPIS) using a double injection of technetium-99m ethyl cysteinate dimer without any intervention, and compared it with that of the BPI values obtained by graphical analysis (BPIG). The BPIS values in the first (x) and second sessions (y) correlated closely (y=0.921x+0.036; r=0.962; n=64; s.e.e.=0.058 min-1). Although the BPIG values in the first (x) and second sessions (y) also correlated (y=0.942x+0.040; r=0.916; n=64; s.e.e.=0.061 min-1), the correlation coefficient for BPIS was significantly higher than that for BPIG. The reproducibility was dependent on the injection dose ratio of the second session to the first (R). The difference in BPI between the first and second sessions tended to be smaller when 1.5

Assuntos
Circulação Cerebrovascular , Transtornos Cerebrovasculares/fisiopatologia , Cisteína/análogos & derivados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Transtornos Cerebrovasculares/diagnóstico por imagem , Cisteína/administração & dosagem , Feminino , Humanos , Masculino , Compostos de Organotecnécio/administração & dosagem , Compostos Radiofarmacêuticos/administração & dosagem , Reprodutibilidade dos Testes
17.
Neural Netw ; 14(9): 1265-78, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11718425

RESUMO

This paper describes the cascade neural network design algorithm (CNNDA), a new algorithm for designing compact, two-hidden-layer artificial neural networks (ANNs). This algorithm determines an ANN's architecture with connection weights automatically. The design strategy used in the CNNDA was intended to optimize both the generalization ability and the training time of ANNs. In order to improve the generalization ability, the CNDDA uses a combination of constructive and pruning algorithms and bounded fan-ins of the hidden nodes. A new training approach, by which the input weights of a hidden node are temporarily frozen when its output does not change much after a few successive training cycles, was used in the CNNDA for reducing the computational cost and the training time. The CNNDA was tested on several benchmarks including the cancer, diabetes and character-recognition problems in ANNs. The experimental results show that the CNNDA can produce compact ANNs with good generalization ability and short training time in comparison with other algorithms.


Assuntos
Algoritmos , Redes Neurais de Computação , Design de Software
18.
Gan To Kagaku Ryoho ; 28(11): 1558-61, 2001 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11707979

RESUMO

Thirty-one patients with advanced pancreatic carcinoma and liver metastases were treated by hepatic and splenic arterial infusion chemotherapy after transcatheter peripancreatic arterial embolization. The response rate for these 31 patients was 61.3%, with a mean survival period of 17.8 +/- 3.2 months and a 50% survival period of 12 months. By site of the primary tumor, the response rate for pancreatic head and body carcinoma was 81%, with a mean survival period of 21.6 +/- 4.0 months and a 50% survival period of 17 months, whereas the response rate for pancreatic caudal carcinoma was 20%, with a mean survival period of 6.1 +/- 0.5 months and a 50% survival period of 6 months. We believe that the current chemotherapy is an effective treatment for advanced pancreatic cancer with liver metastases.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/mortalidade , Idoso , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Pessoa de Meia-Idade , Pâncreas/irrigação sanguínea , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Artéria Esplênica , Taxa de Sobrevida
19.
Gan To Kagaku Ryoho ; 28(11): 1562-4, 2001 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11707980

RESUMO

Dual chambers ports were implanted in 7 patients with advanced pancreatic carcinoma and metastatic liver tumors to connect a 3.3 Fr catheter as an indwelling catheter. In comparison with the implantation of a pair of Single chamber ports, implanting a Dual chambers port entails some technical difficulties, but has some benefits in terms of stabler placement, a smaller incision, reduction of medical fees, and improved QOL of patients.


Assuntos
Bombas de Infusão Implantáveis/normas , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/tratamento farmacológico , Cateteres de Demora , Feminino , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Artéria Esplênica
20.
Br J Pharmacol ; 134(7): 1403-10, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11724745

RESUMO

1. Human umbilical vein endothelial cells cultured on a transparent silicone chamber were subjected to a short stretch pulse (ca. 1 s, 5-25% stretch) of their substrate and following increases in intracellular Ca(2+) concentration ([Ca(2+)](i)) were measured by fluorescence intensity ratiometry using fura-2. 2. In response to mechanical stretch, the cells in HEPES buffered saline exhibited a Ca(2+) transient in a dose dependent way. The response was completely dependent on external Ca(2+) and inhibited by gadolinium (Gd(3+)), suggesting that it was mediated by the activation of a stretch activated cation channel (SACatC). 3. Interestingly, the stretch induced Ca(2+) transient was significantly augmented in the presence of basic polypeptide, protamine. This augmented Ca(2+) response was inhibited neither by Gd(3+) nor by the deprivation of external Ca(2+), indicating that the SACatC is not responsible for this phenomenon. 4. In contrast, this augmentation was inhibited by depletion of intracellular Ca(2+) stores with thapsigargin or by the pretreatment with phospholipase inhibitors such as U73122 and manoalide. 5. These results suggest the presence of a metabotropic mechanoreceptor distinct from the SACatC in vascular endothelium. This augmented [Ca(2+)](i) increase may contribute to the vasodilating response induced by protamine during heparin neutralization in cardiac surgery.


Assuntos
Cálcio/metabolismo , Endotélio Vascular/efeitos dos fármacos , Protaminas/farmacologia , Cálcio/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Estrenos/farmacologia , Gadolínio/farmacologia , Humanos , Manganês/metabolismo , Pirrolidinonas/farmacologia , Estresse Mecânico , Terpenos/farmacologia , Tapsigargina/farmacologia , Fatores de Tempo
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