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1.
Phys Rev Lett ; 126(23): 236801, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34170165

RESUMO

Spin-charge conversion via spin-orbit interaction is one of the core concepts in the current spintronics research. The efficiency of the interconversion between charge and spin current is estimated based on Berry curvature of Bloch wave function in the linear-response regime. Beyond the linear regime, nonlinear spin-charge conversion in the higher-order electric field terms has recently been demonstrated in noncentrosymmetric materials with nontrivial spin texture in the momentum space. Here, we report the observation of the nonlinear charge-spin conversion in a nominally centrosymmetric oxide material SrIrO_{3} by breaking inversion symmetry at the interface. A large second-order magnetoelectric coefficient is observed at room temperature because of the antisymmetric spin-orbit interaction at the interface of Dirac semimetallic bands, which is subject to the symmetry constraint of the substrates. Our study suggests that nonlinear spin-charge conversion can be induced in many materials with strong spin-orbit interaction at the interface by breaking the local inversion symmetry to give rise to spin splitting in otherwise spin degenerate systems.

2.
Leuk Res ; 61: 68-76, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28917156

RESUMO

Fms-like tyrosine kinase 3 (FLT3) is highly expressed in mixed-lineage leukemia (MLL) gene-rearranged acute lymphoblastic leukemia (MLL+ALL) with a dismal prognosis. We previously reported that FLT3 ligand (FL) stimulation induced cell cycle arrest in MLL+ALL cells leading to resistance against anti-leukemic agents. Given that FL stimulation enhanced transforming growth factor (TGF)ß1 mRNA levels in MLL+ALL cells, we extensively examined the effect of TGFß1 on the cell cycle progression and chemosensitivity in MLL+ALL cells, and found that TGFß1 stimulation induced MLL+ALL cells into cell cycle arrest resistant to arabinosyl cytosine; its effect was markedly enhanced in synergy with FL. Thus, it is likely that TGFß1 and FL, both abundantly produced by bone marrow stromal cells, function in a coordinated manner to render MLL+ALL cells chemoresistant, which should lead to the development of minimal residual disease (MRD) resulting in relapse. The use of inhibitors against FLT3 and TGFß1 may become a useful strategy for eradicating MRD in MLL+ALL.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteínas de Membrana/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Western Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/fisiologia , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Humanos , Proteína de Leucina Linfoide-Mieloide/genética , Análise de Sequência com Séries de Oligonucleotídeos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Reação em Cadeia da Polimerase em Tempo Real , Tirosina Quinase 3 Semelhante a fms/metabolismo
3.
Insect Mol Biol ; 26(1): 13-24, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27792261

RESUMO

Insecticide use exerts a tremendous selection force on house fly populations, but the frequencies of the initial resistance mutations may not reach high levels if they have a significant fitness cost in the absence of insecticides. However, with the continued use of the same (or similar) insecticides, it is expected that new mutations (conferring equal or greater resistance, but less of a fitness cost) will evolve. Pyrethroid insecticides target the insect voltage sensitive sodium channel (VSSC) and have been widely used for control of house flies at animal production facilities for more than three decades. There are three Vssc mutations known that cause resistance to pyrethroids in house flies: knockdown resistance (kdr, L1014F), kdr-his (L1014H) and super-kdr (M918T + L1014F). Whether or not there are any new mutations in house fly populations has not been examined for decades. We collected house flies from a dairy in Kansas (USA) and selected this population for three generations. We discovered multiple new Vssc alleles, including two that give very high levels of resistance to most pyrethroids. The importance of these findings to understanding the evolution of insecticide resistance, designing appropriate resistance monitoring and management schemes, and the future of pyrethroids for house fly control are discussed.


Assuntos
Evolução Molecular , Moscas Domésticas/genética , Inseticidas , Piretrinas , Canais de Sódio Disparados por Voltagem/genética , Adaptação Biológica , Alelos , Animais , Sequência de Bases , Feminino , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Masculino , Dados de Sequência Molecular , Seleção Genética
4.
Insect Mol Biol ; 25(2): 126-37, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26691197

RESUMO

Target site insensitivity because of mutations in the voltage-sensitive sodium channel gene (Vssc) is a major mechanism of resistance to pyrethroid insecticides in the house fly, Musca domestica. There are three known Vssc alleles that confer resistance to pyrethroids in the house fly: knock down resistance (kdr; L1014F), super-kdr (M918T + L1014F) and kdr-his (L1014H), but there has been no side-by-side comparison of the resistance levels that they confer. We compared the levels of resistance conferred by the three Vssc alleles in congenic strains to 19 structurally diverse pyrethroids, and compared the full-length Vssc cDNA sequences from each strain. Generally, the levels of resistance conferred were kdr-his < kdr < super-kdr. However, there was significant variation in this pattern, especially for super-kdr, for which both high and low resistance ratios were observed for several pyrethroids. We also examined the levels of resistance in heterozygotes. Resistance in each of the hybrids was generally inherited as an incompletely recessive trait, except for the kdr-his/kdr hybrids, which showed incompletely to completely dominant resistance (ie had resistance levels comparable to kdr homozygotes). The importance of these results to understanding the frequencies of these resistance alleles in natural populations, the evolution of insecticide resistance and resistance management strategies are discussed.


Assuntos
Moscas Domésticas/genética , Resistência a Inseticidas/genética , Canais de Sódio/genética , Alelos , Animais , DNA Complementar/genética , Heterozigoto , Moscas Domésticas/efeitos dos fármacos , Inseticidas/farmacologia , Mutação , Piretrinas/farmacologia
7.
Nanotechnology ; 26(23): 234001, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-25990026

RESUMO

In this study, we extracted the essential spatiotemporal dynamics that allow an amoeboid organism to solve a computationally demanding problem and adapt to its environment, thereby proposing a nature-inspired nanoarchitectonic computing system, which we implemented using a network of nanowire devices called 'electrical Brownian ratchets (EBRs)'. By utilizing the fluctuations generated from thermal energy in nanowire devices, we used our system to solve the satisfiability problem, which is a highly complex combinatorial problem related to a wide variety of practical applications. We evaluated the dependency of the solution search speed on its exploration parameter, which characterizes the fluctuation intensity of EBRs, using a simulation model of our system called 'AmoebaSAT-Brownian'. We found that AmoebaSAT-Brownian enhanced the solution searching speed dramatically when we imposed some constraints on the fluctuations in its time series and it outperformed a well-known stochastic local search method. These results suggest a new computing paradigm, which may allow high-speed problem solving to be implemented by interacting nanoscale devices with low power consumption.


Assuntos
Amoeba/fisiologia , Metodologias Computacionais , Nanotecnologia , Animais , Simulação por Computador , Modelos Teóricos , Nanofios
8.
Curr Mol Med ; 15(3): 193-205, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25817860

RESUMO

N-methyl-D-aspartate (NMDA) receptor plays important roles in learning and memory. NMDA receptors are a tetramer that consists of two glycine-binding subunits GluN1, two glutamate-binding subunits (i.e., GluN2A, GluN2B, GluN2C, and GluN2D), a combination of a GluN2 subunit and glycine-binding GluN3 subunit (i.e., GluN3A or GluN3B), or two GluN3 subunits. Recent studies revealed that the specific expression and distribution of each subunit are deeply involved in neural excitability, plasticity, and synaptic deficits. The present article summarizes reports on the dysfunction of NMDA receptors and responsible subunits in various neurological and psychiatric disorders, including schizophrenia, autoimmune-induced glutamatergic receptor dysfunction, mood disorders, and autism. A key role for the GluN2D subunit in NMDA receptor antagonist-induced psychosis has been recently revealed.


Assuntos
Transtornos Mentais/metabolismo , Subunidades Proteicas/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Encéfalo/metabolismo , Predisposição Genética para Doença , Humanos , Transtornos Mentais/genética
9.
Cell Death Discov ; 1: 15015, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551449

RESUMO

Inhibitory PAS domain protein (IPAS), a repressor of hypoxia-inducible factor-dependent transcription under hypoxia, was found to exert pro-apoptotic activity in oxidative stress-induced cell death. However, physiological and pathological processes associated with this activity are not known. Here we show that IPAS is a key molecule involved in neuronal cell death in Parkinson's disease (PD). IPAS was ubiquitinated by Parkin for proteasomal degradation following carbonyl cyanide m-chlorophenyl hydrazone treatment. Phosphorylation of IPAS at Thr12 by PTEN-induced putative kinase 1 (PINK1) was required for ubiquitination to occur. Activation of the PINK1-Parkin pathway attenuated IPAS-dependent apoptosis. IPAS was markedly induced in the midbrain following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration, and IPAS-deficient mice showed resistance to MPTP-induced degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc). A significant increase in IPAS expression was found in SNpc neurons in patients with sporadic PD. These results indicate a mechanism of neurodegeneration in PD.

10.
Br J Pharmacol ; 171(5): 1287-98, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24670150

RESUMO

BACKGROUND AND PURPOSE: Melanin-concentrating hormone receptor 1 (MCH1 receptor) antagonists are being considered as anti-obesity agents. The present study reports a new class of MCH1 receptor antagonists with an 8-methylquinoline scaffold. The molecular mechanism of MCH1 receptor blockade by these antagonists was examined. EXPERIMENTAL APPROACH: The pharmacological properties of the 8-methylquinolines as exemplified by MQ1 were evaluated by use of multiple biophysical and cell-based functional assays. KEY RESULTS: Multiple signalling pathways for Gαi and Gαq , and ß-arrestin were inhibited by MQ1. Furthermore, MQ1 produced an insurmountable antagonism, causing a rightward shift of the curve for concentration-dependent binding of MCH along with a progressive reduction of the maximal response. The dissociation kinetics for MQ1 were determined from washout experiments as well as by affinity selection-MS. In short, MQ1 was shown to be a slowly dissociating reversible MCH1 receptor blocker with a low Koff value. CONCLUSION AND IMPLICATIONS: This is the first time that a slowly dissociating negative allosteric modulator of the MCH1 receptor has been demonstrated to inhibit the numerous signalling pathways of this receptor. The characteristics of MQ1 are superior and distinct from previously reported MCH1 receptor antagonists, making members of this chemotype attractive as drug candidates.


Assuntos
Fármacos Antiobesidade/farmacologia , Benzamidas/farmacologia , Quinolinas/farmacologia , Receptores de Somatostatina/antagonistas & inibidores , Regulação Alostérica , Animais , Células CHO , Cricetulus , Humanos , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo
11.
Mol Psychiatry ; 19(1): 55-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23183491

RESUMO

Opioids, such as morphine and fentanyl, are widely used as effective analgesics for the treatment of acute and chronic pain. In addition, the opioid system has a key role in the rewarding effects of morphine, ethanol, cocaine and various other drugs. Although opioid sensitivity is well known to vary widely among individual subjects, several candidate genetic polymorphisms reported so far are not sufficient for fully understanding the wide range of interindividual differences in human opioid sensitivity. By conducting a multistage genome-wide association study (GWAS) in healthy subjects, we found that genetic polymorphisms within a linkage disequilibrium block that spans 2q33.3-2q34 were strongly associated with the requirements for postoperative opioid analgesics after painful cosmetic surgery. The C allele of the best candidate single-nucleotide polymorphism (SNP), rs2952768, was associated with more analgesic requirements, and consistent results were obtained in patients who underwent abdominal surgery. In addition, carriers of the C allele in this SNP exhibited less vulnerability to severe drug dependence in patients with methamphetamine dependence, alcohol dependence, and eating disorders and a lower 'Reward Dependence' score on a personality questionnaire in healthy subjects. Furthermore, the C/C genotype of this SNP was significantly associated with the elevated expression of a neighboring gene, CREB1. These results show that SNPs in this locus are the most potent genetic factors associated with human opioid sensitivity known to date, affecting both the efficacy of opioid analgesics and liability to severe substance dependence. Our findings provide valuable information for the personalized treatment of pain and drug dependence.


Assuntos
Analgésicos Opioides/administração & dosagem , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 2/genética , Metilases de Modificação do DNA/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Escalas de Graduação Psiquiátrica , Procedimentos de Cirurgia Plástica/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/genética , Adulto Jovem
12.
Heredity (Edinb) ; 111(3): 216-26, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23632895

RESUMO

Insecticide resistance develops as a genetic factor (allele) conferring lower susceptibility to insecticides proliferates within a target insect population under strong positive selection. Intriguingly, a resistance allele pre-existing in a population often bears a series of further adaptive allelic variants through new mutations. This phenomenon occasionally results in replacement of the predominating resistance allele by fitter new derivatives, and consequently, development of greater resistance at the population level. The overexpression of the cytochrome P450 gene CYP9M10 is associated with pyrethroid resistance in the southern house mosquito Culex quinquefasciatus. Previously, we have found two genealogically related overexpressing CYP9M10 haplotypes, which differ in gene copy number (duplicated and non-duplicated). The duplicated haplotype was derived from the non-duplicated overproducer probably recently. In the present study, we investigated allelic series of CYP9M10 involved in three C. quinquefasciatus laboratory colonies recently collected from three different localities. Duplicated and non-duplicated overproducing haplotypes coexisted in African and Asian colonies indicating a global distribution of both haplotype lineages. The duplicated haplotypes both in the Asian and African colonies were associated with higher expression levels and stronger resistance than non-duplicated overproducing haplotypes. There were slight variation in expression level among the non-duplicated overproducing haplotypes. The nucleotide sequences in coding and upstream regions among members of this group also showed a little diversity. Non-duplicated overproducing haplotypes with relatively higher expression were genealogically closer to the duplicated haplotypes than the other non-duplicated overproducing haplotypes, suggesting multiple cis-acting mutations before duplication.


Assuntos
Culex/efeitos dos fármacos , Culex/enzimologia , Sistema Enzimático do Citocromo P-450/genética , Variação Genética , Proteínas de Insetos/genética , Resistência a Inseticidas , Inseticidas/farmacologia , Alelos , Animais , Culex/classificação , Culex/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Haplótipos , Proteínas de Insetos/metabolismo , Filogenia
13.
Nat Commun ; 3: 845, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22617285

RESUMO

A change of magnetic flux through a circuit induces an electromotive force. By analogy, a recently predicted force that results from the motion of non-uniform spin structures has been termed the spin-motive force. Although recent experiments seem to confirm its presence, a direct signature of the spin-motive force has remained elusive. Here we report the observation of a real-time spin-motive force produced by the gyration of a magnetic vortex core. We find a good agreement between the experimental results, theory and micromagnetic simulations, which taken as a whole provide strong evidence in favour of a spin-motive force.

14.
Curr Neuropharmacol ; 9(1): 96-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21886570

RESUMO

MDMA (3,4-methylenedioxymethamphetamine) is reportedly severely toxic to both dopamine (DA) and serotonin neurons. MDMA significantly reduces the number of DA neurons in the substantia nigra, but not in the nucleus accumbens, indicating that MDMA causes selective destruction of DA neurons in the nigrostriatal pathway, sparing the mesolimbic pathway. Parkinson's disease (PD) is a neurodegenerative disorder of multifactorial origin. The pathological hallmark of PD is the degeneration of DA neurons in the nigrostriatal pathway. Mutations in the parkin gene are frequently observed in autosomal recessive parkinsonism in humans. Parkin is hypothesized to protect against neurotoxic insult, and we attempted to clarify the role of parkin in MDMA-induced hyperthermia, one of the causal factors of neuronal damage, using parkin knockout mice. Body temperature was measured rectally before and 15, 30, 45, and 60 min after intraperitoneal injection of MDMA (30 mg/kg) at an ambient temperature of 22 ± 2°C. Significantly enhanced hyper-thermia after MDMA injection was observed in heterozygous and homozygous parkin knockout mice compared with wildtype mice, suggesting that parkin plays a protective role in MDMA neurotoxicity.

15.
Dermatology ; 221(3): 211-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20720387

RESUMO

Pyoderma gangrenosum (PG) of the eyelid is extremely rare, and its proper management is essential for the preservation of visual function. Here, we report 2 cases of PG of the eyelid with intraorbital involvement. In both cases, the skin and intraorbital lesions improved after systemic immunosuppressive therapies; however, corneal perforation occurred in 1 case. In order to assess the clinical features of PG of the eyelid and to obtain clues for optimal treatment, we reviewed 15 well-documented cases in the literature, including the present cases. Corneal perforation occurred in 4 cases and defective ocular motility in 1 case. Three patients eventually underwent enucleation of the affected eye. Our cases and the literature review clearly indicate that MRI is a powerful tool for evaluating the extent of extracutaneous PG lesions around the eye and that early diagnosis and immediate immunosuppressive therapy are crucial for the preservation of visual acuity.


Assuntos
Ciclosporina/uso terapêutico , Doenças Palpebrais/tratamento farmacológico , Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Prednisolona/uso terapêutico , Pioderma Gangrenoso/tratamento farmacológico , Idoso , Quimioterapia Combinada , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pioderma Gangrenoso/diagnóstico , Pioderma Gangrenoso/patologia
16.
Insect Mol Biol ; 19(6): 717-26, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20629774

RESUMO

Previous studies on a strain of Culex pipiens quinquefasciatus from Saudi Arabia indicated permethrin resistance was a result of cytochrome P450 mediated detoxification and kdr. The P450 detoxification was found to be larval specific and associated with a fitness cost in certain environments. The P450 responsible for resistance (and the fitness cost) has not been identified, but recently two candidate P450s (CYP4H34 and CYP9M10) have been found. We measured cytochrome P450 and cytochrome b5 content as well as the expression levels of CYP4H34 and CYP9M10 in a susceptible (SLAB) and two isogenic strains (isolated by repeated backcrossing and selection) of mosquito (ISOP450 and ISOJPAL) resistant to permethrin. Cytochrome P450 protein levels of the resistant strains were significantly higher (1.5-fold) than SLAB, but were not significantly different from one another. Expression of CYP4H34 in the larvae and adults of the resistant (ISOP450 and ISOJPAL) and susceptible (SLAB) strains were not statistically different. CYP9M10 was found to be significantly over-expressed in larvae of both permethrin-resistant isogenic strains (1800-fold in ISOP450 and 870-fold in ISOJPAL) when compared to SLAB. Partial sequence analysis of CYP9M10 revealed eight polymorphic sites that distinguished the susceptible allele from the resistant allele. We conclude that CYP9M10 is linked to permethrin resistance in these strains of C. p. quinquefasciatus, and is likely to be the P450 gene responsible for resistance in these strains.


Assuntos
Culex/genética , Sistema Enzimático do Citocromo P-450/genética , Genes de Insetos/genética , Resistência a Inseticidas/genética , Permetrina , Animais , Sequência de Bases , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b5/metabolismo , Regulação Enzimológica da Expressão Gênica , Frequência do Gene , Genótipo , Larva , Dados de Sequência Molecular , Alinhamento de Sequência
17.
Br J Cancer ; 100(8): 1257-66, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19319137

RESUMO

Cholangiocarcinoma is an intractable cancer, with no effective therapy other than surgical resection. Elevated vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expressions are associated with the progression of cholangiocarcinoma. We therefore examined whether inhibition of VEGFR and EGFR could be a potential therapeutic target for cholangiocarcinoma. Vandetanib (ZD6474, ZACTIMA), a VEGFR-2/EGFR inhibitor, was evaluated. Four human cholangiocarcinoma cell lines were molecularly characterised and investigated for their response to vandetanib. In vitro, two cell lines (OZ and HuCCT1), both of which harboured KRAS mutation, were refractory to vandetanib, one cell line (TGBC24TKB) was somewhat resistant, and another cell line (TKKK) was sensitive. The most sensitive cell line (TKKK) had EGFR amplification. Vandetanib significantly inhibited the growth of TKKK xenografts at doses > or = 12.5 mg kg(-1) day(-1) (P<0.05), but higher doses (50 mg kg(-1) day(-1), P<0.05) of vandetanib were required to inhibit the growth of OZ xenografts. Vandetanib (25 mg kg(-1) day(-1)) also significantly (P=0.006) prolonged the time to metastasis in an intravenous model of TKKK metastasis. Inhibiting both VEGFR and EGFR signalling appears a promising therapeutic approach for cholangiocarcinoma. The absence of KRAS mutation and the presence of EGFR amplification may be potential predictive molecular marker of sensitivity to EGFR-targeted therapy in cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Piperidinas/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Receptores ErbB/genética , Feminino , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Japão , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
18.
Phys Med Biol ; 53(13): 3543-9, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18552417

RESUMO

Proteins are expected to exhibit collective vibrational modes at terahertz frequencies. We have developed a promising approach to measure these motions by using a membrane device to hold samples. Samples of bovine serum albumin (BSA) in native and thermally denatured conformations were measured using terahertz time-domain spectroscopy. Clear differences were observed in transmittance and phase between native-conformation BSA samples and thermally denatured BSA samples. Time-domain data shows that samples exhibited relative time shifts when compared with a standard. Results suggest that there were differences in dielectric responses in the BSA samples, and these are probably associated with molecular conformational changes in the membrane device.


Assuntos
Micro-Ondas , Soroalbumina Bovina/análise , Análise Espectral/métodos , Microscopia Eletrônica de Varredura/métodos , Conformação Molecular , Desnaturação Proteica , Soroalbumina Bovina/química , Análise Espectral/instrumentação , Temperatura , Fatores de Tempo
19.
Kyobu Geka ; 61(5): 355-8, 2008 May.
Artigo em Japonês | MEDLINE | ID: mdl-18464477

RESUMO

An 82-year-old man developed simultaneous stent thrombosis 11 days after the implantation of a sirolimus-eluting stent (SES) in the proximal left anterior descending artery (LAD) and the proximal right coronary artery (RCA). The patient immediately underwent percutaneous coronary intervention; however, his condition became critical due to the development of recurrent stent thrombosis, and emergent coronary artery bypass grafting with saphenous vein grafts was performed. Postoperative angiography showed good patency of both grafts; thrombus formation in the LAD and RCA was negative. Since the patient had a history of liver dysfunction due to ticlopidine administration, the thienopyridine derivative was not administered; this was believed to be the main cause of subacute stent thrombosis. He was administered aspirin, cilostazol, and sarpogrelate instead. A good postoperative course was achieved only using aspirin. This case demonstrates that simultaneous SES thrombosis in multivessel lesions poses a life-threatening situation.


Assuntos
Ponte de Artéria Coronária , Trombose Coronária/etiologia , Trombose Coronária/cirurgia , Stents Farmacológicos/efeitos adversos , Sirolimo/administração & dosagem , Idoso de 80 Anos ou mais , Angina Pectoris/terapia , Aspirina/administração & dosagem , Reestenose Coronária/etiologia , Emergências , Humanos , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Resultado do Tratamento
20.
Br J Cancer ; 98(2): 418-25, 2008 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-18087285

RESUMO

Epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and human epidermal growth factor receptor 2 (HER2) have been considered as potential therapeutic targets in cholangiocarcinoma, but no studies have yet clarified the clinicopathological or prognostic significance of these molecules. Immunohistochemical expression of these molecules was assessed retrospectively in 236 cases of cholangiocarcinoma, as well as associations between the expression of these molecules and clinicopathological factors or clinical outcome. The proportions of positive cases for EGFR, VEGF, and HER2 overexpression were 27.4, 53.8, and 0.9% in intrahepatic cholangiocarcinoma (IHCC), and 19.2, 59.2, and 8.5% in extrahepatic cholangiocarcinoma (EHCC), respectively. Clinicopathologically, EGFR overexpression was associated with macroscopic type (P=0.0120), lymph node metastasis (P=0.0006), tumour stage (P=0.0424), lymphatic vessel invasion (P=0.0371), and perineural invasion (P=0.0459) in EHCC, and VEGF overexpression with intrahepatic metastasis (P=0.0224) in IHCC. Multivariate analysis showed that EGFR expression was a significant prognostic factor (hazard ratio (HR), 2.67; 95% confidence interval (CI), 1.52-4.69; P=0.0006) and also a risk factor for tumour recurrence (HR, 1.89; 95% CI, 1.05-3.39, P=0.0335) in IHCC. These results suggest that EGFR expression is associated with tumour progression and VEGF expression may be involved in haematogenic metastasis in cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/genética , Genes erbB-1 , Genes erbB-2 , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/metabolismo , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Análise de Sobrevida
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