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1.
Ann Oncol ; 30(9): 1521-1530, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31282941

RESUMO

BACKGROUND: The tumor immune microenvironment (TIME) of lung cancer brain metastasis is largely unexplored. We carried out immune profiling and sequencing analysis of paired resected primary tumors and brain metastases of non-small-cell lung carcinoma (NSCLC). PATIENTS AND METHODS: TIME profiling of archival formalin-fixed and paraffin-embedded specimens of paired primary tumors and brain metastases from 39 patients with surgically resected NSCLCs was carried out using a 770 immune gene expression panel and by T-cell receptor beta repertoire (TCRß) sequencing. Immunohistochemistry was carried out for validation. Targeted sequencing was carried out to catalog hot spot mutations in cancer genes. RESULTS: Somatic hot spot mutations were mostly shared between both tumor sites (28/39 patients; 71%). We identified 161 differentially expressed genes, indicating inhibition of dendritic cell maturation, Th1, and leukocyte extravasation signaling pathways, in brain metastases compared with primary tumors (P < 0.01). The proinflammatory cell adhesion molecule vascular cell adhesion protein 1 was significantly suppressed in brain metastases compared with primary tumors. Brain metastases exhibited lower T cell and elevated macrophage infiltration compared with primary tumors (P < 0.001). T-cell clones were expanded in 64% of brain metastases compared with their corresponding primary tumors. Furthermore, while TCR repertoires were largely shared between paired brain metastases and primary tumors, T-cell densities were sparse in the metastases. CONCLUSION: We present findings that suggest that the TIME in brain metastases from NSCLC is immunosuppressed and comprises immune phenotypes (e.g. immunosuppressive tumor-associated macrophages) that may help guide immunotherapeutic strategies for NSCLC brain metastases.


Assuntos
Biomarcadores Tumorais/imunologia , Neoplasias Encefálicas/imunologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Proteínas de Neoplasias/imunologia , Microambiente Tumoral/imunologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Células Dendríticas/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação/genética , Proteínas de Neoplasias/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Microambiente Tumoral/genética
2.
World J Surg Oncol ; 15(1): 179, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962578

RESUMO

BACKGROUND: Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) is a promising real-time navigation method in the surgical resection of malignant gliomas. In order to determine whether this method is applicable to metastatic brain tumors, we evaluated the usefulness of intraoperative fluorescence patterns and histopathological features in patients with metastatic brain tumors. METHODS: We retrospectively reviewed the cases of 16 patients with metastatic brain tumors who underwent intraoperative 5-ALA fluorescence-guided resection. Patients were given 20 mg/kg of 5-ALA orally 2 h prior to the surgery. High-powered excitation illumination and a low-pass filter (420, 450, or 500 nm) were used to visualize the fluorescence of protoporphyrin IX (PpIX), the 5-ALA metabolite. We evaluated the relationships between the fluorescence and histopathological findings in both tumoral and peritumoral brain tissue. RESULTS: Tumoral PpIX fluorescence was seen in only 5 patients (31%); in the remaining 11 patients (69%), there was no fluorescence in the tumor bulk itself. In 14 patients (86%), vague fluorescence was seen in peritumoral brain tissue, at a thickness of 2-6 mm. The histopathological examination found cancer cell invasion of adjacent brain tissue in 75% of patients (12/16), at a mean ± SD depth of 1.4 ± 1.0 mm (range 0.2-3.4 mm) from the microscopic border of the tumor. There was a moderate correlation between vague fluorescence in adjacent brain tissue and the depth of cancer cell invasion (P = 0.004). CONCLUSION: Peritumoral fluorescence may be a good intraoperative indicator of tumor extent, preceding more complete microscopic gross total resection. TRIAL REGISTRATION: Institutional Review Board of Osaka Medical College No. 42, registered February 17, 1998, and No. 300, registered April 1, 2008. They were retrospectively registered.


Assuntos
Ácido Aminolevulínico/administração & dosagem , Neoplasias Encefálicas/cirurgia , Procedimentos Neurocirúrgicos/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Protoporfirinas/química , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Ácido Aminolevulínico/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Feminino , Fluorescência , Humanos , Cuidados Intraoperatórios/métodos , Imageamento por Ressonância Magnética , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Procedimentos Neurocirúrgicos/instrumentação , Estudos Retrospectivos , Cirurgia Assistida por Computador/instrumentação
3.
J Viral Hepat ; 23(12): 977-984, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27476460

RESUMO

We compared Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) levels between patients with chronic hepatitis B (n=249) and chronic hepatitis C (n=386) based on the degree of liver fibrosis. We examined WFA+ -M2BP levels in patients with F4 (cirrhosis), F3 or more (advanced fibrosis) and F2 or more (significant fibrosis) in the two groups. We further examined the relationship between five fibrosis markers and the degree of fibrosis. The WFA+ -M2BP values ranged from 0.25 cut-off index (COI) to 12.9 COI in patients with hepatitis B and 0.34-20.0 COI in patients with hepatitis C (P<.0001). The median WFA+ -M2BP values in F4 in the two groups were 2.83 COI in patients with hepatitis B and 5.03 COI in patients with hepatitis C (P=.0046). The median WFA+ -M2BP values in F3 or more in the two groups were 1.79 COI in patients with hepatitis B and 3.79 COI in patients with hepatitis C (P<.0001). The median WFA+ -M2BP values in F2 or more in the two groups were 1.49 COI in the hepatitis B cohort and 3.19 COI in the hepatitis C group (P<.0001). Among five liver fibrosis markers, WFA+ -M2BP had the highest correlation coefficient (rs =.629) in terms of correlation with the degree of fibrosis in the patients with hepatitis C and had the second highest rs value (.415) in the hepatitis B group. Although WFA+ -M2BP could be a useful indicator of liver fibrosis, WFA+ -M2BP levels in the two groups significantly differed even in the same degree of fibrosis. Individual cut-off values in each aetiology for the degree of fibrosis should be determined.


Assuntos
Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/metabolismo , Hepatite B Crônica/patologia , Hepatite C Crônica/patologia , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/metabolismo , Lectinas de Plantas/metabolismo , Receptores de N-Acetilglucosamina/metabolismo , Soro/química , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Adulto Jovem
4.
Tissue Antigens ; 85(4): 252-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25789826

RESUMO

The present study investigates the human leucocyte antigen (HLA) allele and haplotype frequencies in Japanese population. We carried out the frequency analysis in 5824 families living across Japanese archipelago. The studied population has mainly been typed for the purpose of transplant, especially the hematopoietic stem cell transplantation (HSCT). We determined HLA class I (A, B, and C) and HLA class II (DRB1) using Luminex technology. The haplotypes were directly counted by segregation. A total of 44 HLA-A, 29 HLA-C, 75 HLA-B, and 42 HLA-DRB1 alleles were identified. In the HLA haplotypes of A-C-B-DRB1 and C-B, the pattern of linkage disequilibrium peculiar to Japanese population has been confirmed. Moreover, the haplotype frequencies based on family study was compared with the frequencies estimated by maximum likelihood estimation (MLE), and the equivalent results were obtained. The allele and haplotype frequencies obtained in this study could be useful for anthropology, transplantation therapy, and disease association studies.


Assuntos
Frequência do Gene , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Antígenos HLA-DQ/genética , Cadeias HLA-DRB1/genética , Adulto , Alelos , Povo Asiático , Criança , Família , Feminino , Expressão Gênica , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Antígenos HLA-C/imunologia , Antígenos HLA-DQ/imunologia , Cadeias HLA-DRB1/imunologia , Haplótipos , Teste de Histocompatibilidade , Humanos , Funções Verossimilhança , Desequilíbrio de Ligação , Masculino , Linhagem , Doadores de Tecidos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38763084

RESUMO

OBJECTIVE: This narrative review aimed to summarize studies assessing the effects of parenteral fish oil on neurodevelopment in preterm infants. METHODS: PubMed was searched (July 1985 to October 2023). We reviewed randomized controlled trials, and observational studies assessing intravenous lipid emulsion with fish oil in preterm infants (born less than 37 weeks' gestation), that reported long-term neurodevelopmental outcomes. RESULTS: We identified four publications relating to three randomized controlled trials in addition to four cohort studies. Study designs and outcomes were heterogenous and precluded meta-analyses. Results of trials were null for a selection of neurodevelopmental outcomes, however possible benefits of parenteral fish oil supplementation for neurodevelopment was reported in three cohort studies. Certainty of the evidence is hindered by methodological limitations of available trials and observational studies. CONCLUSIONS: Further research is required to firmly establish the effects of parenteral fish oil on preterm neurodevelopment.


Assuntos
Óleos de Peixe , Recém-Nascido Prematuro , Humanos , Recém-Nascido Prematuro/crescimento & desenvolvimento , Óleos de Peixe/administração & dosagem , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto , Emulsões Gordurosas Intravenosas/administração & dosagem , Desenvolvimento Infantil/efeitos dos fármacos , Nutrição Parenteral
6.
Br J Cancer ; 108(3): 644-52, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23361059

RESUMO

BACKGROUND: Recent studies have demonstrated that microRNAs (miRNAs) are stably detectable in blood and can serve as useful biomarkers for cancer. METHODS: We performed an miRNA array using serum samples obtained from oesophageal squamous cell carcinoma (ESCC) patients or healthy controls. MiR-1246 was the most markedly elevated in ESCC patients. Therefore, miR-1246 was selected as a candidate for further analysis. The serum miR-1246 level in 46 healthy controls and 101 ESCC patients was evaluated and compared among various clinicopathological characteristics. MiR-1246 expressions in tissue, exosomal, and cellular samples were also examined. RESULTS: Serum miR-1246 alone yielded an receiver-operating characteristic curve area of 0.754, with 71.3% sensitivity and 73.9% specificity for distinguishing ESCC patients from healthy controls. Serum miR-1246 was significantly correlated with the TNM stage and showed to be the strongest independent risk factor for poor survival (HR, 4.032; P=0.017). Unlike the tendency shown in previous reports, miR-1246 was not upregulated in ESCC tissue samples. Furthermore, exosomal miR-1246 did not reflect the abundance in the cell of origin. CONCLUSION: These data support our contention that serum miR-1246 has strong potential as a novel diagnostic and prognostic biomarker in ESCC, and its releasing mechanism is selective and independent of tissue miRNA abundance.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/sangue , Neoplasias Esofágicas/genética , Esôfago/metabolismo , Perfilação da Expressão Gênica , MicroRNAs/sangue , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/patologia , Exossomos/metabolismo , Feminino , Humanos , Metástase Linfática , Masculino , MicroRNAs/genética , Metástase Neoplásica , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Br J Cancer ; 109(3): 545-51, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23868010

RESUMO

BACKGROUND: We conducted a multicentre feasibility study for single agent long-term S-1 chemotherapy following docetaxel plus cisplatin in patients with curatively resected stage II-IIIA non-small cell lung cancer. METHODS: Patients received three cycles of docetaxel (60 mg m(-2)) plus cisplatin (80 mg m(-2)) and then received S-1 (40 mg m(-2) twice daily) for 14 consecutive days with a 1-week rest for >6 months (maximum, 1 year). The primary end point was feasibility, which was defined as the proportion of patients who completed eight or more cycles of S-1 chemotherapy. If the lower 95% confidence interval (CI) of this proportion was 50% or more, then the treatment was considered as feasible. The sample size was set at 125 patients. RESULTS: One hundred and thirty-one patients were enrolled, of whom 129 patients were eligible and assessable. In all, 109 patients (84.5%) completed 3 cycles of docetaxel plus cisplatin and 66 patients (51.2%, 95% CI: 42.5-59.8) completed 8 or more cycles of S-1 treatment. Grade 3/4 toxicities during the S-1 chemotherapy included anaemia (7.3%), neutropaenia (3.7%), and anorexia (3.7%). CONCLUSION: The toxicity level was acceptable, although the results did not meet our criterion for feasibility. Modification of the treatment schedule for S-1 chemotherapy might improve the treatment compliance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/cirurgia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Docetaxel , Esquema de Medicação , Combinação de Medicamentos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/administração & dosagem , Ácido Oxônico/efeitos adversos , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Adulto Jovem
8.
Ann Oncol ; 24(5): 1326-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23277482

RESUMO

BACKGROUND: A phase III study (Lung Cancer Evaluation of TS-1) previously demonstrated noninferiority in terms of overall survival (OS) at interim analysis for carboplatin-S-1 compared with carboplatin-paclitaxel for first-line treatment of advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 564 patients were randomly assigned to receive either carboplatin on day 1 plus oral S-1 on days 1-14 or carboplatin-paclitaxel on day 1 every 21 days. Updated results and post hoc subgroup analysis according to tumor histology are presented. RESULTS: The updated analysis revealed a median OS of 15.2 months in the carboplatin-S-1 arm and 13.1 months in the carboplatin-paclitaxel arm, with a hazard ratio (HR) of 0.956 [95% confidence interval (CI) 0.793-1.151], consistent with the previous primary analysis. Median OS was 14.0 months in the carboplatin-S-1 arm and 10.6 months in the carboplatin-paclitaxel arm (HR 0.713; 95% CI 0.476-1.068) for patients with squamous cell carcinoma (SCC), with corresponding values of 15.5 and 13.9 months (HR 1.060; 95% CI 0.859-1.308) for those with non-SCC. CONCLUSIONS: These results establish the efficacy and safety of carboplatin-S-1 in patients with advanced NSCLC regardless of tumor histology.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Ácido Oxônico/uso terapêutico , Paclitaxel/uso terapêutico , Tegafur/uso terapêutico , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Reagentes de Ligações Cruzadas/efeitos adversos , Reagentes de Ligações Cruzadas/uso terapêutico , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Humanos , Japão , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/efeitos adversos , Paclitaxel/efeitos adversos , Tegafur/efeitos adversos , Resultado do Tratamento , Adulto Jovem
9.
J Clin Pharm Ther ; 38(1): 12-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22882748

RESUMO

WHAT IS KNOWN AND OBJECTIVE: It has been reported that ibuprofen interferes with the antiplatelet effect of low-dose aspirin. This interaction is ascribed to steric hindrance at the active site of cyclooxygenase-1 by ibuprofen, when aspirin is administered after ibuprofen. However, whether other non-steroidal anti-inflammatory drugs (NSAIDs) interact with aspirin similarly is not well defined. The aim of this study was to assess the influence of nine NSAIDs on the antiplatelet effect of aspirin. METHODS: We investigated the antiplatelet effect of NSAIDs using steady-state plasma concentration reported after usual doses. We studied the in vitro antiplatelet effect of NSAID alone, aspirin alone, aspirin before NSAID addition and aspirin after NSAID addition to platelet-rich plasma. The rates of platelet aggregation induced by collagen were determined. The final concentration of aspirin used was the 50% effective concentration (EC(50)) previously estimated in vitro. RESULTS AND DISCUSSION: Ibuprofen and mefenamic acid interfere with the antiplatelet effect of aspirin when added before the latter. The rate of platelet aggregation was reduced by 48·1% and 22·7%, respectively. The other NSAIDs tested did not significantly affect the aspirin antiplatelet effect when exposure was prior to aspirin. None of the nine NSAIDs altered the aspirin effect if administration followed that of aspirin. WHAT IS NEW AND CONCLUSION: Naproxen and flurbiprofen have significant antiplatelet effects at plasma concentrations seen with usual doses. Our in vitro model suggests that the antiplatelet effect of aspirin is significantly diminished when taken after, but not before, ibuprofen or mefenamic acid. None of the other NSAIDs tested had any effect irrespective of the timing of dosing.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Colágeno/administração & dosagem , Interações Medicamentosas , Feminino , Humanos , Técnicas In Vitro , Masculino , Fatores de Tempo
10.
Water Sci Technol ; 68(3): 591-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23925187

RESUMO

A down-flow hanging sponge reactor, constructed by connecting three identical units in series, was applied to the treatment of artificial wastewater containing phenol and ammonia under high salinity conditions (10.9 g-Cl(-)/L). The theoretical hydraulic retention time (HRT) of each unit was 4 h (total HRT = 12 h). To enhance denitrification by effluent recirculation, the effluent recirculation ratio was increased in increments ranging from 0.0 to 2.0. The concentration of total ammonia nitrogen (TAN), NO2-N, and NO3-N in the final effluent as a proportion of the TAN in the influent was determined to calculate the unrecovered, or denitrification, proportion. The denitrification proportion of the reactor was equivalent to 19.1 ± 14.1% with no effluent recirculation; however, this was increased to 58.6 ± 6.2% when the effluent recirculation ratio was increased to 1.5. Further increasing the effluent recirculation ratio to 2.0 resulted in a decrease in the denitrification proportion to 50.9 ± 9.3%. Activity assays of nitrification and denitrification, as well as 16S rRNA gene sequence analysis, revealed that denitrification occurred primarily in the upper sections of the reactor, while nitrification increased in the lower sections of the reactor. Gene sequence analysis revealed that denitrification by Azoarcus-like species using phenol as an electron donor was dominant.


Assuntos
Reatores Biológicos/microbiologia , Desnitrificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Amônia/química , Amônia/metabolismo , Azoarcus/genética , Azoarcus/isolamento & purificação , DNA Bacteriano/análise , Modelos Químicos , Nitrogênio/química , Nitrogênio/metabolismo , Fenol/química , RNA Ribossômico 16S/genética
11.
Diabetologia ; 54(8): 2183-91, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21614569

RESUMO

AIMS/HYPOTHESIS: We have previously shown a negative correlation between serum bilirubin levels and prevalence of type 2 diabetes, suggesting that bilirubin inhibits development of this disease. To confirm this hypothesis, we investigated whether administration of biliverdin, the precursor of bilirubin, protects against the deterioration of glucose tolerance in db/db mice, a rodent model of type 2 diabetes. METHODS: Biliverdin (20 mg/kg daily) was orally administered to 5-week-old db/db mice for 4 weeks. After 4 weeks of treatment, i.p. glucose tolerance and insulin tolerance tests were performed. Insulin content was evaluated by immunostaining and ELISA. Oxidative stress markers (8-hydroxy-2'-deoxyguansosine and dihydroethidium staining) and expression of NADPH oxidase components Pdx1 and Bax were also evaluated in isolated islets. RESULTS: Treatment with biliverdin partially prevented worsening of hyperglycaemia and glucose intolerance in db/db mice. This effect was accompanied by a significant increase in insulin content and Pdx1 expression, and a significant decrease of apoptosis and Bax expression in pancreatic islets from db/db mice. At the same time, levels of oxidative stress markers and NADPH oxidase component production in islets were normalised. Biliverdin had little effect on HOMA of insulin resistance or insulin resistance evaluated by insulin tolerance tests. CONCLUSIONS/INTERPRETATION: Biliverdin may protect against progressive worsening of glucose tolerance in db/db mice, mainly via inhibition of oxidative stress-induced beta cell damage.


Assuntos
Biliverdina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Intolerância à Glucose/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Técnicas In Vitro , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Nature ; 437(7058): 522-4, 2005 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16177784

RESUMO

Thyristors are a class of nonlinear electronic device that exhibit bistable resistance--that is, they can be switched between two different conductance states. Thyristors are widely used as inverters (direct to alternating current converters) and for the smooth control of power in a variety of applications such as motors and refrigerators. Materials and structures that exhibit nonlinear resistance of this sort are not only useful for practical applications: they also provide systems for exploring fundamental aspects of solid-state and statistical physics. Here we report the discovery of a giant nonlinear resistance effect in the conducting organic salt theta-(BEDT-TTF)2CsCo(SCN)4, the voltage-current characteristics of which are essentially the same as those of a conventional thyristor. This intrinsic organic thyristor works as an inverter, generating an alternating current when a static direct-current voltage is applied. Whereas conventional thyristors consist of a series of diodes (their nonlinearity comes from interface effects at the p-n junctions), the present salt exhibits giant nonlinear resistance as a bulk phenomenon. We attribute the origin of this effect to the current-induced melting of insulating charge-order domains, an intrinsically non-equilibrium phenomenon in the sense that ordered domains are melted by a steady flow.

14.
Sci Rep ; 11(1): 4277, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608561

RESUMO

We report the first observation of room temperature spontaneous electric polarization in an electronic ferroelectric material, a YbFe2O4 single crystal. The observation was based on second harmonic generation (SHG), a nonlinear optical process. Tensor analysis of the SHG signal revealed that this material has a polar charge superstructure with Cm symmetry. This result settles the long-term discussion on the uncertainty about electronic ferroelectric properties, including the charge order structure. We present a complete picture of the polar charge ordering of this material via consistent results from two different characterization methods. The SHG signal shows the same temperature dependence as the superlattice signal observed in neutron diffraction experiments. These results prove ferroelectric coupling to electron ordering in YbFe2O4, which results in electronic ferroelectricity which is enabled by the real space ordering of iron cations with different valences. The existence of electronic ferroelectricity holds promise for future electronics technologies where devices run a thousand times faster than frequency of the present CPU (a few gigahertz) embedded in smartphones, etc.

15.
Adv Colloid Interface Sci ; 282: 102206, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32707348

RESUMO

Mixed adsorbed film of cationic surfactant and linear alkane at the air-water interface shows two-dimensional phase transition from surface liquid to surface frozen states upon cooling. This surface phase transition is accompanying with the compression of electrical double layer due to the enhancement of counterion adsorption onto the adsorbed surfactant cation and therefore induces the thinning of the foam film at fixed disjoining pressures. However, by increasing the disjoining pressure, surfactant ions desorb from the surface to reduce the electric repulsion between the adsorbed films on the both sides of the foam film. As a result, the foam film stabilized by the surfactant-alkane mixed adsorbed films showed unique thickening transition on the disjoining pressure isotherm due to the back reaction to the surface liquid films. In this review, we will summarize all these features based on the previously published papers and newly obtained results.

16.
Vet J ; 266: 105571, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33323173

RESUMO

Canine transitional cell carcinoma (cTCC) is the most common malignant tumour in the urinary bladder: it is highly invasive and exhibits metastatic characteristics. Inflammation is also strongly related to cTCC. Epithelial tumours often exhibit a mesenchymal cell phenotype during tumour invasion and metastasis owing to epithelial-mesenchymal transition (EMT), which is often induced in chronic inflammation. The aim of this retrospective study was to investigate the expression of epithelial and mesenchymal cell markers in tumour cells and to evaluate its relationship with prognosis of cTCC. In this study, 29 dogs with cTCC who underwent surgical treatment were enrolled. Clinical parameters were reviewed using medical records. Tissue expression of epithelial and mesenchymal markers was evaluated by immunohistochemical analysis. The association between the expression of mesenchymal cell markers and clinical parameters, including prognosis, was statistically examined. In five normal bladder tissues used as controls, no expression of mesenchymal markers was observed, except for one tissue that expressed fibronectin. Conversely, epithelial tumour cells expressed vimentin and fibronectin in 23/29 and 19/28 cTCC tissues, respectively. Regarding clinical parameters, vimentin score in Miniature Dachshunds was significantly higher than those in other dog breeds (P < 0.001). Multivariate survival analyses revealed that age>12 years was related to shorter progression-free survival (P = 0.02). Higher vimentin score, lower fibronectin score, and advanced clinical T stage were significantly correlated with shorter median survival time (P < 0.05). The results of this study indicate that vimentin expression was associated with cTCC progression. Further studies are needed to examine the incidence and relevance of EMT in cTCC.


Assuntos
Carcinoma de Células de Transição/veterinária , Doenças do Cão/patologia , Transição Epitelial-Mesenquimal , Neoplasias da Bexiga Urinária/veterinária , Fatores Etários , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Doenças do Cão/metabolismo , Cães , Feminino , Fibronectinas/metabolismo , Imuno-Histoquímica , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/metabolismo , Vimentina/metabolismo
17.
Kyobu Geka ; 62(8 Suppl): 739-43, 2009 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-20715702

RESUMO

Photodynamic therapy (PDT), neodymium yttrium aluminum garnet (Nd-YAG) laser therapy, electrocautery and microwave coagulation therapy are therapeutic options available for management of endobronchial malignancies. All of these treatment modalities have been used for both palliation of late obstructing cancers, and more recently have been used as primary treatment of early stage lung cancers. Only PDT has the curative potential for patients with early superficial squamous cell carcinoma. Nd-YAG laser therapy is used for direct thermal ablation of tissue in endobronchial malignancy. This equipment is the most widely used type of laser for bronchoscopic interventions because it has sufficient power to vaporize tissues and produces an excellent coagulation effect. But the risks of perforation and bleeding are high. Endobronchial electrocautery is the use of high-frequency electrical current that generates heat due to tissue resistance, resulting in destruction of tissue. Argon plasma coagulation (APC) is a form of noncontact electrocoagulation. The risks of perforation and igniting are much lower than with the Nd-YAG laser therapy. Microwave coagulation therapy refers to the use of all electromagnetic methods for inducing tumor destruction by using devices with frequencies of 2450 MHz. It is important to select these treatment methods appropriately according to each case.


Assuntos
Neoplasias Brônquicas/cirurgia , Terapia a Laser/métodos , Neoplasias Brônquicas/tratamento farmacológico , Humanos , Micro-Ondas/uso terapêutico , Fotoquimioterapia/métodos
18.
Food Chem Toxicol ; 46(6): 2190-200, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18381228

RESUMO

The beneficial effects of tea catechins are well documented. We evaluated the genotoxic potential of a green tea catechin preparation using established genotoxicity assays, including a bacterial reverse mutation assay (Ames test), a chromosomal aberration assay in cultured Chinese hamster lung cells (CHL/IU), a mouse lymphoma L5178Y/tk assay, and a bone marrow micronucleus (MN) assay in ICR CD mice and SD rats. No significant increases in the number of revertant colonies were observed in the Ames test, but positive responses were observed in two in vitro assays: the chromosomal aberration assay and mouse lymphoma L5178/tk assay. However, the in vivo study demonstrated no significant increase in micronucleated polychromatic erythrocytes (MNPCE) in the bone marrow of both ICR CD mice and SD rats administered a high dose of the green tea catechin preparation up to 2000mg/kg. Combined with favorable epidemiological information suggesting a chemopreventive effect of tea catechins on carcinogenesis, we conclude that green tea catechin presents no significant genotoxic concern under the anticipated conditions of use. These results are consistent with other genotoxicity studies of tea catechins, which show minimal, if any, genotoxic potential.


Assuntos
Catequina/toxicidade , Mutagênicos , Chá/química , Animais , Células da Medula Óssea/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Aberrações Cromossômicas/efeitos dos fármacos , Cricetinae , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos ICR , Testes para Micronúcleos , Testes de Mutagenicidade , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Timidina Quinase/genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-18519209

RESUMO

We report our recent discovery of novel ferroelectricity arising from the polar ordering of Fe(3)+ and Fe(2)+ in a mixed valence triangular lattice oxide LuFe(2)O(4), where the electric polarization is not a result of ionic displacement. The polar ordering of Fe(3)+ and Fe(2)+ was confirmed with a resonant x-ray scattering study in SPring-8. The origin of such ordering is the competitive interaction between Fe(3)+ and Fe(2)+ in the triangular lattice, i.e., the charge frustration. The polar superlattice of Fe(3)+ and Fe(2)+ develops below 350 K, where the electric polarization appears. The ferroelectricity arising from the polar charge ordering or the polar electron distribution may have great potential for the future application of ferroelectrics.


Assuntos
Eletrônica , Compostos Férricos/química , Modelos Químicos , Simulação por Computador , Condutividade Elétrica , Elétrons
20.
Kyobu Geka ; 61(4): 323-6, 2008 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-18411697

RESUMO

Safety management of bronchoscopic examination and treatment is devided into 3 phases. Patient information should be provided before the procedure. Also written informed conscent should be obtained after the information of advantage and disadvantage of examination/treatment. Bronchoscopists and well-trained nurses should manage both the procedure itself and patient condition. Through check up of patient is necessary to avoid late complications after the procedure. Due to the increase in the number of interventional bronchoscopies, the management of patients is getting more important. Safety management should be developed by wide-range of medical team including bronchoscopists, nurses and technical staff.


Assuntos
Broncoscopia/efeitos adversos , Gestão de Riscos/métodos , Humanos
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