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1.
Ann ICRP ; 50(1_suppl): 74-81, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34353146

RESUMO

After the accident at Fukushima Daiichi nuclear power plant on 11 March 2011, radioactive materials were released into the atmosphere resulting in environmental contamination. Following the implementation of environmental decontamination efforts, the Radiation Dose Registration Centre of the Radiation Effects Association established the radiation dose registration system for decontamination and related workers to consolidate and prevent the loss of radiation records. This article presents statistics on the radiation doses of decontamination and related workers using official records. Since approximately 10 years have passed since the accident in Fukushima, the types of work conducted in the affected restricted areas have changed over time. Therefore, changes in radiation dose for each type of work and comparisons with nuclear workers are presented.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Proteção Radiológica , Descontaminação , Humanos , Japão , Centrais Nucleares , Doses de Radiação
2.
Nutr Metab Cardiovasc Dis ; 27(3): 249-259, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28062181

RESUMO

BACKGROUND AND AIMS: Epicatechin (EC) intake has been suggested to be beneficial for the prevention of cardiovascular disorders, and it is well known that adipose tissue inflammation is one of the major risk factors for coronary heart diseases. The purpose of the present study was to determine the in vitro and in vivo effects of EC on adipose tissue inflammation and obesity. METHODS AND RESULTS: DNA microarray analysis was performed to evaluate the effects of EC on gene expression in adipocytes co-cultured with bacterial endotoxin-stimulated macrophages. To determine the in vivo effects of the catechin, C57BL/6 mice were fed either a high-fat diet (HFD) or HFD combined with EC, and metabolic changes were observed EC suppressed the expression of many inflammatory genes in the adipocytes co-cultured with endotoxin-stimulated macrophages. Specifically, EC markedly suppressed chemokine (CC motif) ligand 19 (CCL19) expression. The target cell of EC appeared to macrophages. The in vivo study indicated that mice fed the EC-supplemented HFD were protected from diet-induced obesity and insulin resistance. Accordingly, the expression levels of genes associated with inflammation in adipose tissue and in the liver were downregulated in this group of mice. CONCLUSIONS: EC exerts beneficial effects for the prevention of adipose tissue inflammation and insulin resistance. Since we previously reported that mice deficient in the CCL19 receptor were protected from diet-induced obesity and insulin resistance, it can be concluded that the beneficial effects of EC could be mediated, at least in part, by marked suppression of CCL19 expression.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Catequina/farmacologia , Quimiocina CCL19/metabolismo , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina , Obesidade/prevenção & controle , Paniculite/prevenção & controle , Células 3T3-L1 , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Quimiocina CCL19/genética , Técnicas de Cocultura , Modelos Animais de Doenças , Regulação para Baixo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/genética , Obesidade/metabolismo , Paniculite/etiologia , Paniculite/genética , Paniculite/metabolismo , Células RAW 264.7 , Fatores de Tempo
3.
Transplant Proc ; 46(3): 963-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767391

RESUMO

In the present study, we aimed to compare the pancreas volumetric changes before and after living donor surgery for pancreas transplantation, using three-dimensional (3D) computed tomography (CT) and glucose metabolism. Pancreatic volume (PV) measurement using 3D CT was performed in 13 consecutive donors who underwent distal pancreatectomy for simultaneous living donor pancreas and kidney transplantation. PV was measured using a workstation before and 3 months after living donor operation. As the parameters of glucose metabolism, hemoglobin A1c (HbA1c) level, fasting plasma glucose (FPG) level, body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR), and insulinogenic index (IGI) were examined simultaneously with the PV measurement. The preoperative and postoperative PVs of pancreas was 30 ± 5 mL and 42 ± 9 mL, respectively. The postoperative PV was significantly higher than the preoperative PV (P < .01) and increased by approximately 40% at 3 months after surgery. The postoperative FPG and HbA1c levels were significantly higher than the preoperative values (P < .01). BMI decreased significantly after surgery (P < .01). No differences in HOMA-IR and IGI were noted between before and after surgery. Diabetes mellitus was not observed any of the 13 living donors during this period. Distal pancreatectomy for living donors caused an increase in the PV and maintained insulin resistance, but it was not sufficient to maintain glucose metabolism at the preoperative state.


Assuntos
Glicemia/metabolismo , Doadores Vivos , Transplante de Pâncreas , Pâncreas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
4.
Transplant Proc ; 46(2): 321-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24655953

RESUMO

We have performed retroperitoneoscopic nephrectomy for living kidney donor surgery since 2000. Recently, we introduced single-site retroperitoneoscopic donor nephrectomy (RDN) as a less invasive donor surgery. The procedure was performed in 7 donors (5 women and 2 men) by a single surgeon. The mean age and body mass index of the donors were 62.6 years (range, 53-74 years) and 24.3 kg/m(2) (range, 22.3-29.0 kg/m(2)), respectively. Left-sided nephrectomy was performed in all the donors. The donors were positioned in the right lateral position, and a 7-cm-long incision was made in the left flank. The incision was extended to the retroperitoneal space using the muscle-splitting technique. The retroperitoneal space was then expanded using an inflation balloon. A GelPOINT Advanced Access Platform (Applied Medical, Rancho Santa Margarita, Calif, United States) was placed in the incision. The subsequent technique and equipment were the same as those used in conventional 3-port RDN. The renal artery and vein were dissected using a vascular stapler, and the kidney graft was directly extracted through the incision. The mean operative time was 197 ± 28 minutes, warm ischemic time was 4.1 ± 1.2 minutes, and blood loss was 75 ± 113 mL. No statistical differences were found between the present method and conventional 3-port RDN. Intraoperative and postoperative complications were not observed in any of the donors. Graft function after transplantation was good, and delayed graft function was not observed in any of the recipients. This technique can be easily introduced in the clinical setting by surgeons experienced in RDN.


Assuntos
Transplante de Rim , Doadores Vivos , Nefrectomia/métodos , Segurança do Paciente , Espaço Retroperitoneal/cirurgia , Idoso , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade
5.
Transplant Proc ; 46(2): 372-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24655966

RESUMO

BACKGROUND: Transforming growth factor (TGF)-ß1 may contribute to chronic allograft nephropathy and graft loss; however, the exact molecular mechanism remains unclear. Therefore, we assess the relationship between TGF-ß1 gene polymorphisms, expression, and development of allograft nephropathy. METHODS: We studied 135 renal transplant recipients at our hospital. TGF-ß1 gene polymorphisms (codons 10 and 25) were determined from peripheral blood leukocyte DNA. Plasma TGF-ß1 mRNA was measured by real-time polymerase chain reaction and TGF-ß1 protein levels were assessed by enzyme-linked immunosorbent assay. The relationship between TGF-ß1 genotyping, expression, and rejection and results of renal biopsy were evaluated. RESULTS: The genotype frequency of transplant recipients was 49.6%, 30.4%, and 20.0% for C/T, C/C and T/T at codon 10, 100% for G/G at codon 25, respectively. According to the criteria of Banff '97 classification, 24 cases were classified as acute rejection and whose genotypes were 16, 3, and 5 cases for C/T, C/C and T/T at codon 10. Plasma mRNA expression was elevated in 14 cases and decreased in 8 cases after acute rejection. We measured 267 specimens of TGF-ß1 protein and there was no relation between amount of TGF-ß1 protein and mRNA. CONCLUSION: Our results suggest that the relationship between plasma TGF-ß1 expression and the development of allograft nephropathy remains uncertain. Frequency of allograft rejection differ with TGF-ß1 codon 10 genotypes and the high-risk genotype was different from the reports of other countries.


Assuntos
Transplante de Rim , RNA Mensageiro/genética , Fator de Crescimento Transformador beta1/genética , Feminino , Genótipo , Humanos , Japão , Masculino , Fator de Crescimento Transformador beta1/metabolismo
6.
Transplant Proc ; 46(2): 556-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24656011

RESUMO

PURPOSE: BK polyomavirus-associated nephropathy (BKVAN) is an important cause of renal allograft loss. Immunosuppression therapy in renal transplant recipients can lead to the reactivation of latent BK polyomavirus (BKV) infection, leading to BK viruria and viremia. This single-center study aimed to clarify the association between quantitative measurement of BKV DNA and the progression of BKV infection, and secondly to identify the risk factors associated with the evolution of viruria to viremia. METHODS: We retrospectively analyzed 266 patients who underwent renal transplantation in our center from October 2006 to February 2013. We examined the viral loads of BKV in urine and plasma by quantitative real-time polymerase chain reaction assay after screening all of the recipients by urinary sediment examination. BKVAN was diagnosed by histological examination with immunohistochemistry of the large T antigen in biopsy specimens. RESULTS: Overall, 22 recipients showed BK viruria alone, whereas 22 progressed to BK viremia, of which 6 patients were diagnosed with BKVAN. Among BKVAN patients, 2 cases progressed to graft loss at 59 months and 31 months after diagnosis, respectively. In BKVAN group, the plasma viral loads were significantly higher than those in viremia without nephropathy (P < .001). Multivariate analysis revealed that the evolution of viruria to viremia was associated with recipient age over 55 years (odds ratio, 32.08; 95% confidence interval, 2.1-489.5) and tacrolimus exposure (odds ratio, 11.98; 95% confidence interval, 1.34-107.04). CONCLUSIONS: The progression from viremia to BKVAN was strongly associated with increasing plasma viral loads for BKV DNA. The cutoff value of 1 × 10(4) copies/mL for plasma viral loads could differentiate between BKVAN and viremia alone. Further, recipient age over 55 years and tacrolimus exposure were independently associated with the evolution of viruria to viremia.


Assuntos
Vírus BK/genética , DNA Viral/genética , Transplante de Rim , Infecções por Polyomavirus/complicações , Vírus BK/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carga Viral
7.
Transplant Proc ; 46(2): 651-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24656037

RESUMO

Common iliac artery stenosis after renal transplantation is a rare complication; it can occur in the course of hypertension and renal dysfunction. We report a case of suspected renal allograft rejection with iliac artery stenosis proximal to a transplanted kidney. A 52-year-old man with a history of cadaveric kidney transplantation 26 years previously underwent a second cadaveric kidney transplantation in the left iliac fossa because of graft failure 3 years before. In June 2012, the patient had progressive renal dysfunction. In July, a percutaneous needle biopsy was taken, and it showed no rejection; however, his renal function continued to get worse through September. A percutaneous allograft renal biopsy was performed under ultrasound guidance and showed hyperplasia of the juxtaglomerular apparatus and renin granules. Magnetic resonance angiography was used to evaluate the arteries in the pelvis and showed left common iliac artery stenosis, and a stent was placed. After percutaneous intervention, the patient's ankle brachial pressure index was within the normal range and the allograft function had improved.


Assuntos
Biópsia , Constrição Patológica/diagnóstico , Transplante de Rim , Rim/patologia , Artéria Renal/patologia , Adulto , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Transplant Proc ; 43(9): 3273-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22099775

RESUMO

For a safe living pancreas donoration for transplantation, we evaluated the function of the residual pancreas head using 11C-methionine positron emission tomography (PET) in 13 cases before and after distal pancreatectomy. After 6 hours of fasting, we intravenously administered 11C-methionine (370 to 740 MBq), performing PET at 30 minutes thereafter. 11C-methionine PET uptake in the pancreas head was expressed as a standardized uptake value (SUV) for comparison before versus after surgery: 17.3 ± 2.5 versus 17.4 ± 4.9, respectively, demonstrating no significant difference. However, the changes in SUVs of the residual pancreas head showed three patterns after surgery. The SUVs were elevated in three donors after surgery, hypermetabolite type; maintained in five donors, normometabolite type; and decreased in five donors hypometabolite type. The percentages of subjects with a postoperative HbA1c value more than 5.8%, the upper normal limit, were 33% in hypermetabolite type; 40% in the normometabolite type; and 60% in the hypometabolite type. Although diabetes mellitus has not developed in any of the 13 donors, the pancreatic head function after distal pancreatectomy was slightly decreased, especially among the hypometabolite type. To avoid postoperative diabetes mellitus for a prolonged period, donors who show decreased SUVs after surgery should be strictly followed. In conclusion, 11C-methionine PET may be a potent modality to evaluate segmental pancreatic function for a safe living donor pancreatectomy.


Assuntos
Radioisótopos de Carbono , Metionina , Transplante de Pâncreas/métodos , Pâncreas/metabolismo , Adulto , Idoso , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/terapia , Feminino , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Pâncreas/fisiologia , Tomografia por Emissão de Pósitrons/métodos , Fatores de Tempo
9.
Br J Cancer ; 102(11): 1592-9, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20461084

RESUMO

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) regulates the expression of genes that mediate cell survival, proliferation, and angiogenesis and is aberrantly activated in various types of malignancies, including renal cell carcinoma (RCC). We examined whether it could be a novel therapeutic target for RCC by using the STAT3 inhibitor WP1066. METHODS: The antitumour activities and related mechanisms of WP1066 were investigated in vitro on renal cancer cell lines and in vivo on murine xenografts. RESULTS: In Caki-1 and 786-O renal cancer cells, 5 muM WP1066 prevented the phosphorylation of STAT3, and 2.5 muM WP1066 significantly (P<0.01) inhibited cell survival and proliferation. WP1066 suppressed the expression of Bcl-2, induced apoptosis, and inhibited the basal and hypoxia-induced expression of HIF1alpha and HIF2alpha, as well as vascular endothelial growth factor secretion into cell culture medium. Human umbilical vascular endothelial cells cocultured with media from WP1066-treated cells showed significantly reduced tubulogenesis (P<0.05). Systemic oral administration of WP1066 to mice for 19 days significantly inhibited the growth of Caki-1 xenograft tumours (P<0.05), and pathological analysis of xenografts of WP1066-treated mice showed decreased immunostaining of phosphorylated STAT3 and reduced length of CD34-positive vessels (P<0.05). CONCLUSION: Our results suggest that using WP1066 to inhibit the STAT3 signalling pathway could be a novel therapeutic strategy against RCC.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Piridinas/uso terapêutico , Fator de Transcrição STAT3/antagonistas & inibidores , Tirfostinas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Piridinas/farmacologia , Tirfostinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Scand J Immunol ; 71(6): 447-51, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20500697

RESUMO

We identify possible differences in the cytokine/chemokine profiles in cerebrospinal fluid (CSF) from children with encephalopathy and febrile seizure. Interleukin (IL)-1beta, 2, 4, 5, 6, 7, 8, 10, 12, 13, 17, interferon-gamma, tumour necrosis factor-alpha, granulocyte colony-stimulating factor, granulocyte monocyte colony-stimulating factor, monocyte chemoattractant protein-1 and macrophage inflammatory protein-1beta were measured simultaneously in CSF supernatants from children with encephalopathy (n = 8), febrile seizure (n = 16) and fever without neurological complications (n = 8). IL-8 in CSF from children with encephalopathy was significantly elevated compared to that in CSF from children with febrile seizure and fever without neurological complications. IL-8 in CSF was also higher than serum IL-8, suggesting that increased IL-8 was generated from glia cells or astrocytes, not by leakage from serum. Increased IL-8 in CSF in encephalopathy may protect against severe brain damage.


Assuntos
Encefalite/líquido cefalorraquidiano , Encefalite/imunologia , Interleucinas/líquido cefalorraquidiano , Convulsões Febris/líquido cefalorraquidiano , Convulsões Febris/imunologia , Quimiocina CCL2/líquido cefalorraquidiano , Quimiocina CCL2/imunologia , Quimiocina CCL4/líquido cefalorraquidiano , Quimiocina CCL4/imunologia , Pré-Escolar , Feminino , Fator Estimulador de Colônias de Granulócitos/líquido cefalorraquidiano , Fator Estimulador de Colônias de Granulócitos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/líquido cefalorraquidiano , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Imunoensaio , Lactente , Interferon gama/líquido cefalorraquidiano , Interferon gama/imunologia , Interleucinas/imunologia , Masculino , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/líquido cefalorraquidiano , Fator de Necrose Tumoral alfa/imunologia
11.
Br J Radiol ; 83(994): 823-30, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20442278

RESUMO

Early pancreatic cancer is small and limited to the pancreas. In contrast, small pancreatic cancer may include peripancreatic vasculature or metastasis involvement. This study evaluates images of early pancreatic cancer on multidetector CT (MDCT) using contrast-enhanced multiphasic imaging, and post-processed pancreatic duct images. CT findings and pathological features were analysed in eight patients with early pancreatic cancer. Pathological evaluation included location, size and histological grading of the tumour. MDCT evaluation covered the maximum diameter of the main pancreatic duct (MPD), stenosis or obstruction of the MPD, loss of normal lobar texture and associated pancreatitis. Attenuation differences between normal pancreatic parenchyma and the tumour (AD-PT) were also measured. Focal stenosis or obstruction of the MPD with dilatation of the distal MPD was demonstrated in all patients. Associated pancreatitis occurred in six patients with tumours measuring 12 mm or greater. Loss of normal lobar texture was recognised in four cases with the tumour measuring 14 mm or greater. Statistically, low-attenuated lesions and high-attenuated lesions differed with respect to the tumour size (p<0.01), and a positive relationship was demonstrated between the tumour size and AD-PT (r = 0.84). In seven cases, AD-PT is higher during the arterial phase than the pancreatic phase. Early pancreatic cancer appears as low attenuation on early phase, and as high- to iso-attenuation during the pancreatic and delayed phases in respect to the tumour size. Focal stenosis or obstruction of the MPD with dilatation of the distal MPD observed on curved reformation imaging seems important in the diagnosis of early pancreatic cancer.


Assuntos
Linfonodos/diagnóstico por imagem , Ductos Pancreáticos/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Idoso , Detecção Precoce de Câncer , Feminino , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Retrospectivos
13.
Insect Mol Biol ; 18(2): 223-32, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19141111

RESUMO

The fruitfly, Drosophila melanogaster, has three proPO genes (DoxA1, CG8193 and CG2952). DoxA1 has been shown to encode proPO A(1), one of the two proPO isoforms (A(1) and A(3)). However, which of CG8193 or CG2952 encodes proPO A(3) has so far remained elusive. In Northern analysis, CG8193 expression was strong during the larval stage, yet expression of CG2952 was not detected at any stage. Immunoblot analyses with specific antibodies detected CG8193 in the larval hemolymph at the mobility of the endogenous proPOA(3), though no signal for CG2952. These results indicate that the expression of CG2952 is very low and that CG8193 is the gene that encodes proPO A3. Processing of A(1)and A(3) isoforms in adult homogenate and activity of recombinant proPOs were also investigated.


Assuntos
Catecol Oxidase/genética , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Precursores Enzimáticos/genética , Genes de Insetos , Animais , Especificidade de Anticorpos , Catecol Oxidase/sangue , Catecol Oxidase/imunologia , Eletroforese em Gel Bidimensional , Precursores Enzimáticos/sangue , Precursores Enzimáticos/imunologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Immunoblotting , Isoenzimas/sangue , Isoenzimas/genética , Isoenzimas/imunologia , Larva/enzimologia , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo
14.
J Plast Reconstr Aesthet Surg ; 62(1): 108-11, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17959426

RESUMO

Enterocutaneous fistula is an uncommon complication of surgery for colorectal cancer. However, once a fistula has developed, treatment is complicated by previous treatments. Here, we describe an enterocutaneous fistula that developed after multiple treatments for rectal cancer in a 62-year-old woman. The woman had previously undergone several colorectal surgeries, radiation therapy and five courses of chemotherapy. Four years after the final surgery, an enterocutaneous fistula developed between the small intestine and the sacral skin. The fistula was resected, and the resulting defect was successfully reconstructed with a superior gluteal artery perforator flap.


Assuntos
Fístula Intestinal/cirurgia , Complicações Pós-Operatórias/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Terapia Combinada , Feminino , Humanos , Fístula Intestinal/diagnóstico por imagem , Fístula Intestinal/etiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Neoplasias Retais/terapia , Região Sacrococcígea/cirurgia , Tomografia Computadorizada por Raios X
15.
Opt Express ; 17(21): 19190-203, 2009 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20372656

RESUMO

We propose to use a combination of intersubband transitions in semiconductor quantum wells with a two dimensional photonic crystal cavity to obtain narrow, strong thermal radiation spectra. Single peak thermal radiation is obtained due to the Lorentzian shape absorption spectrum of the intersubband transition and the single mode cavity embedded within the photonic band gap. We present an analysis based on the quantum Langevin theory. It is shown that local radiance of the narrow emission peak can be maximized to approximately 80% of the radiation from the blackbody devices when the photon dissipation rates of the cavity mode due to the intersubband absorption and that due to the radiation to the free space modes are equal. Guidelines for concrete device design are introduced, and an example device structure is shown.

16.
Placenta ; 29(12): 1003-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18950855

RESUMO

BeWo cells, derived from human choriocarcinoma, have been known to respond to forskolin or cAMP analogues by differentiating into multinucleated cells- like syncytiotrophoblasts on the surfaces of chorionic villi of the human placenta. In this study, we demonstrated that long-term treatment with forskolin enhances the tight junction (TJ) formation in human placental BeWo cells. Interestingly, AMPK activation and phosphorylation of acetyl-CoA carboxylase (ACC), a molecule downstream from AMPK, were induced by long-term incubation (>12h) with forskolin, despite not being induced by acute stimulation with forskolin. In addition, co-incubation with an AMPK inhibitor, compound C, as well as overexpression of an AMPK dominant negative mutant inhibited forskolin-induced TJ formation. Thus, although the molecular mechanism underlying AMPK activation via the forskolin stimulation is unclear, the TJ formation induced by forskolin is likely to be mediated by the AMPK pathway. Taking into consideration that TJs are present in the normal human placenta, this mechanism may be important for forming the placental barrier system between the fetal and maternal circulations.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Colforsina/farmacologia , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Trofoblastos , Linhagem Celular Tumoral , Coriocarcinoma , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/fisiologia , Humanos , Integrases/genética , Luciferases/genética , Circulação Placentária/fisiologia , Gravidez , Transfecção , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/enzimologia , Neoplasias Uterinas
17.
Transplant Proc ; 40(8): 2562-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929801

RESUMO

For the safe operation of living donor pancreas transplantation, we investigated the utility of 11C-methionine positron emission tomography (PET) to examine the function of the residual pancreatic head in patients with pancreatic disease undergoing distal pancreatectomy and in living donors of pancreas transplantation. After 6 hours of fasting, we intravenously injected 370 to 740 MBq 11C-methionine. PET was scanned 30 minutes after injection. 11C-methionine PET uptake by the pancreatic head versus body/tail was expressed as a standardized uptake value (SUV). The SUVs of the pancreatic head were compared before versus after surgery. The SUVs of the pancreatic head in patients before and after distal pancreatectomy were 15.3 +/- 6.0 and 18.2 +/- 2.4, respectively. The SUVs of the pancreatic head in donors before and after distal pancreatectomy were 16.1 +/- 1.0 and 14.7 +/- 1.4, respectively. Both patients and donors showed no significant difference in SUVs of the pancreatic head before and after surgery. However, the SUVs of the residual pancreatic head were elevated after distal pancreatectomy in 80% of patients and 50% of donors. These data indicated that the function of the pancreatic head may be maintained or improved after distal pancreatectomy. 11C-methionine PET may become a potent modality to evaluate segmental pancreatic function for a safe living donor operation.


Assuntos
Doadores Vivos , Transplante de Pâncreas/métodos , Pâncreas/anatomia & histologia , Pancreatectomia/métodos , Transporte Biológico , Radioisótopos de Carbono , Humanos , Metionina/metabolismo , Pâncreas/diagnóstico por imagem , Pâncreas/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Radiografia
18.
Int J Obes (Lond) ; 32(11): 1725-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18779827

RESUMO

Recent studies have suggested that macrophages were integrated into adipose tissues to interact with adipocytes, thereby exacerbating inflammatory responses. Furthermore, both adipocytes and macrophages appear to express toll-like receptor-4 (TLR-4), and free fatty acids may stimulate cells through TLR-4. Herein, we analyzed genes differentially expressed in adipocytes when co-cultured with macrophages in the presence of a ligand for TLR-4, bacterial lipopolysaccharide (LPS). RAW264.7, a murine macrophage cell line and differentiated 3T3-L1 adipocytes were co-cultured using a transwell system. Genes differentially expressed in adipocytes were analyzed by the DNA microarray method following 4, 8, 12 and 24 h stimulation with 1 ng ml(-1) of Escherichia coli LPS. Randomly selected genes with high expressions were confirmed by quantitative methods at both the gene and the protein level. Co-culture of macrophages and adipocytes with a low LPS concentration (1 ng ml(-1)) markedly upregulated gene expressions associated with inflammation and/or angiogenesis, such as those of interleukin-6 (IL-6), MCP-1, RANTES and CXCL1/KC, in adipocytes. Furthermore, several genes associated with insulin resistance were differentially expressed. Upregulations of genes encoding MCP-1, RANTES and CXC/KC were confirmed by quantitative methods. These results suggest that ligands for TLR-4 stimulate both adipocytes and macrophages to upregulate the expressions of many genes associated with inflammation and/or angiogenesis.


Assuntos
Adipócitos/imunologia , Endotoxinas/imunologia , Macrófagos/imunologia , Receptor 4 Toll-Like/imunologia , Células 3T3-L1/metabolismo , Animais , Linhagem Celular/metabolismo , Endotoxinas/genética , Expressão Gênica , Camundongos , Análise em Microsséries , Receptor 4 Toll-Like/genética , Regulação para Cima
19.
J Phys Condens Matter ; 20(38): 384206, 2008 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21693814

RESUMO

This paper reviews recent advances in our original 2D-plasmon-resonant terahertz emitters. The structure is based on a high-electron-mobility transistor and featured with doubly interdigitated grating gates. The dual grating gates can alternately modulate the 2D electron densities to periodically distribute the plasmonic cavities along the channel, acting as an antenna. The device can emit broadband terahertz radiation even at room temperature from self-oscillating 2D plasmons under the DC-biased conditions. When the device is subjected to laser illumination, photo-generated carriers stimulate the plasma oscillation, resulting in enhancement of the emission. The first sample was fabricated with standard GaAs-based heterostructure material systems, achieving room temperature terahertz emission. The second sample was fabricated in a double-decked HEMT structure in which the grating gate metal layer was replaced with the semiconducting upper-deck 2D electron layer, resulting in enhancement of emission by one order of magnitude.

20.
Int J Artif Organs ; 30(6): 495-500, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17628850

RESUMO

Transplantation of mesothelial cells is used to repair peritoneum that is damaged by surgery, peritonitis, and peritoneal dialysis. The largest obstacle for clinical application of mesothelial cell transplantation is the lack of a reliable source of mesothelial cells. So far, they are isolated from omentum, mesentery, parietal wall and ascites. Procedures used to obtain mesothelial cells from the omentum or mesentery are invasive, however, especially in pre-operative situations. Sufficient amounts of ascites for aspiration can not be obtained under physiological conditions. We have developed a novel method of isolating mesothelial cells from the tunica vaginalis. The tunica vaginalis originates from the peritoneum and descends into the scrotum along with the testis during fetal development. This region provides a source of mesothelial cells that is convenient to approach and free from abdominal complications. Transplantation of autologous mesothelial cells that were isolated from tunica vaginalis was effective in preventing post-operative adhesions. In this review, we summarize mesothelial cell transplantation trials and describe the method of isolating mesothelial cells form the tunica vaginalis. Mesothelial cell transplantation might be widely accepted for clinical use in the near future.


Assuntos
Células Epiteliais/transplante , Epitélio/transplante , Peritônio/patologia , Testículo/ultraestrutura , Animais , Separação Celular , Células Cultivadas , Cães , Masculino , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/complicações , Regeneração/fisiologia , Aderências Teciduais/prevenção & controle , Transplante Autólogo
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