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1.
Ann Neurol ; 95(6): 1040-1054, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520151

RESUMO

OBJECTIVES: Intracerebral hemorrhage (ICH) and cerebral microbleeds (CMB) in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy are more common in East Asian populations than in people of white European ancestry. We hypothesized that the ethnic difference is explained by the East Asian-specific NOTCH3 p.R75P mutation. METHODS: This retrospective observational study included 118 patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy in Japanese and Korean cohorts. We investigated whether the p.R75P mutation is associated with symptomatic ICH and multiple CMB (>5) using quasi-Poisson regression models. We predicted the NOTCH3 extracellular domain protein structures in silico and graded NOTCH3 extracellular domain immunostaining in skin vessels of some patients, with subsequent comparisons between p.R75P and other conventional mutations. RESULTS: Among 63 Japanese patients (median age 55 years; 56% men), 15 had a p.R75P mutation, significantly associated with symptomatic ICH (adjusted relative risk 9.56, 95% CI 2.45-37.31), multiple CMB (3.00, 1.34-6.71), and absence of temporopolar lesions (4.91, 2.29-10.52) after adjustment for age, sex, hypertension, and antithrombotics. In the Korean cohort (n = 55; median age 55 years; 51% men), the p.R75P mutation (n = 13) was also associated with symptomatic ICH (8.11, 1.83-35.89), multiple CMB (1.90, 1.01-3.56), and absence of temporopolar lesions (2.32, 1.08-4.97). Structural analysis revealed solvent-exposed free cysteine thiols in conventional mutations, directly causing aggregation, whereas a stereochemically incompatible proline residue structure in p.R75P lowers correct disulfide bond formation probability, indirectly causing aggregation. Pathologically, the p.R75P mutation resulted in less vascular NOTCH3 extracellular domain accumulation than the other conventional mutations. INTERPRETATION: NOTCH3 p.R75P mutation is associated with hemorrhagic presentations, milder temporopolar lesions, and distinct mutant protein structure properties. ANN NEUROL 2024;95:1040-1054.


Assuntos
CADASIL , Hemorragia Cerebral , Mutação , Receptor Notch3 , Humanos , Masculino , Feminino , Receptor Notch3/genética , Pessoa de Meia-Idade , CADASIL/genética , Estudos Retrospectivos , Hemorragia Cerebral/genética , Idoso , Mutação/genética , Adulto , Japão , República da Coreia , Povo Asiático/genética
2.
Br J Haematol ; 204(5): 1856-1861, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38590011

RESUMO

Bone marrow (BM) examination is a key element in the diagnosis and prognostic grading of myelodysplastic syndromes (MDSs), and obtaining adequate BM cell samples is critical for accurate test results. Massive haemodilution of aspirated BM samples is a well-known problem; however, its incidence in patients with MDS has not been well studied. We report the first study to examine the incidence of massive haemodilution in nationwide BM samples aspirated from patients diagnosed with or suspected of MDS in Japan. Among 283 cases available for analysis, BM smears from 92 cases (32.5%) were hypospicular (massively haemodiluted) and, particularly, no BM particles were observed in 52 cases (18.4%). Regarding hypospicular cases, we examined how the doctors in charge interpreted the BM smears of their patients. In only 19 of 92 cases (20.7%), doctors realised that the BM smears were haemodiluted. Furthermore, the BM biopsy, which can help diagnose hypospicular cases, was oftentimes not performed when the haemodilution was overlooked by doctors (not performed in 50 of 73 such cases). These real-world data highlight that not only researchers who are working to improve diagnostic tests but also clinicians who perform and use diagnostic tests must realise this common and potentially critical problem.


Assuntos
Síndromes Mielodisplásicas , Humanos , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/patologia , Japão/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , Adulto , Exame de Medula Óssea/métodos , Prevalência , Medula Óssea/patologia
3.
Eur J Neurol ; 30(11): 3487-3496, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36708081

RESUMO

BACKGROUND: Cerebral microbleeds (CMBs) influence long-term prognoses of stroke patients. Streptococcus mutans expressing the collagen-binding protein Cnm induces cerebrovascular inflammation, impairing blood brain barrier integrity and causing cerebral bleeding. Here, we examine the association of Cnm-positive S. mutans with CMBs. METHODS: Acute stroke patients were selected from a single-center registry database. Oral carriage of Cnm-positive or Cnm-negative S. mutans was determined using polymerase chain reaction assays. The associations of Cnm-positive S. mutans with CMB number and specifically the presence of >10 CMBs were examined using quasi-Poisson and logistic regression models, respectively. RESULTS: This study included 3154 stroke patients, of which 428 patients (median [interquartile range] age, 73.0 [63.0-81.0] years; 269 men [62.9%]) underwent oral bacterial examinations. In total, 326 patients harbored S. mutans. After excluding four patients without imaging data, we compared patients with Cnm-positive (n = 72) and Cnm-negative (n = 250) S. mutans. Harboring Cnm-positive S. mutans was independently associated with the presence of >10 CMBs (adjusted odds ratio 2.20 [1.18-4.10]) and higher numbers of deep and lobar CMBs (adjusted risk ratio 1.61 [1.14-2.27] for deep; 5.14 [2.78-9.51] for lobar), but not infratentorial CMBs, after adjusting for age, sex, hypertension, stroke type, National Institutes of Health Stroke Scale score, and cerebral amyloid angiopathy. CONCLUSIONS: Harboring Cnm-positive S. mutans was independently associated with a higher number of CMBs in deep and lobar locations. Reducing Cnm-positive S. mutans in the oral cavity may serve as a novel therapeutic approach for stroke.

4.
Biol Pharm Bull ; 45(1): 94-103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34980783

RESUMO

Our previous studies identified that nimesulide analogs which bear a methoxy substituent at the para-position of the phenyl ring could be potential radiotracer candidates for detecting disorders related to cyclooxygenase-2 (COX-2) expression and activity in vivo using positron emission tomography (PET) in the brain. The present study was conducted to evaluate the in vivo characteristics of 11C-labeled para-methoxy nimesulide ([11C]1d) as a brain COX-2-targeted imaging agent compared to other isomeric methoxy analogs of nimesulide ([11C]1b and [11C]1c). [11C]1b-d were synthesized with reasonable yield and purity by the methylation of the O-desmethyl precursor with [11C]methyl triflate in the presence of NaOH at room temperature. We performed in vivo biodistribution analysis, brain PET imaging, ex vivo autoradiography, and metabolite analysis in mice. The uptake of [11C]1b-d was lower in the brain than in other tissues, including in the blood, and both [11C]1c and [11C]1d were rapidly metabolized. However, [11C]1d showed a small, but significant, specific signal and heterogeneous distribution in the brain. In vivo evaluation suggested that [11C]1d might correlate with COX-2 expression in the brain. Given its instability in vivo, [11C]1d seems unsuitable as a brain-COX-2 radioimaging agent. Further structural refinement of these radiotracers is necessary to enhance their uptake in the brain and to achieve sufficient metabolic stability.


Assuntos
Tomografia por Emissão de Pósitrons , Sulfonamidas , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Radioisótopos de Carbono/metabolismo , Ciclo-Oxigenase 2/metabolismo , Camundongos , Tomografia por Emissão de Pósitrons/métodos , Distribuição Tecidual
5.
Acta Med Okayama ; 76(6): 737-742, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36549777

RESUMO

Paraplegia after an operation for acute aortic dissection Stanford type A (AADA) is fairly uncommon, and there is no consensus about optimal treatment. We present a case in which cerebrospinal fluid drainage (CSFD) and permissive hypertension were used for treatment of paraplegia. When the patient showed complete bilateral paraplegia after operation for AADA, we immediately began CSFD and maintained mean arterial blood pressure at over 90 mmHg. His neurological deficit gradually recovered, and he was eventually able to walk without support. The combination of CSFD and permissive hypertension could be a first-line emergent treatment for postoperative paraplegia after AADA surgery.


Assuntos
Dissecção Aórtica , Hipertensão , Masculino , Humanos , Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Vazamento de Líquido Cefalorraquidiano , Hipertensão/complicações , Paraplegia/etiologia , Paraplegia/terapia , Resultado do Tratamento
6.
Br J Clin Pharmacol ; 87(6): 2511-2520, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33202059

RESUMO

AIMS: Ocrelizumab is a humanized monoclonal antibody that selectively targets CD20-positive B cells and is indicated for treatment of patients with relapsing forms of multiple sclerosis (RMS) or primary progressive multiple sclerosis (PPMS). The pharmacokinetics and pharmacodynamics of ocrelizumab in patients with RMS or PPMS were assessed. METHODS: A population pharmacokinetic model was developed based on data from the Phase II study and the Phase III studies OPERA I and OPERA II in patients with RMS. Data from the ORATORIO Phase III study in patients with PPMS became available after model finalization and was used for external model evaluation. RESULTS: The ocrelizumab serum concentration vs time course was accurately described by a 2-compartment model with time-dependent clearance. Body weight was found to be the main covariate. The area under the concentration-time curve over the dosing interval was estimated to be 26% higher for patients with RMS weighing <60 kg and 21% lower for patients weighing >90 kg when compared with the 60-90 kg group. The terminal half-life of ocrelizumab was estimated as 26 days. The extent of B-cell depletion in blood, as the pharmacodynamic marker, was greater with increasing ocrelizumab exposure. CONCLUSION: The pharmacokinetics of ocrelizumab was described with pharmacokinetic parameters typical for an immunoglobulin G1 monoclonal antibody, with body weight as the main covariate. The pharmacokinetics and B-cell depletion in blood were comparable across the RMS and PPMS trials, and the extent of blood B-cell depletion was greater with higher exposure.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Anticorpos Monoclonais Humanizados , Humanos , Fatores Imunológicos , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico
7.
Stroke ; 51(12): 3632-3639, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33148146

RESUMO

BACKGROUND AND PURPOSE: Cerebral microbleeds (CMB) are associated with stroke and cognitive impairment. We previously reported a high prevalence of CMB in people with Streptococcus mutans expressing Cnm, a collagen-binding protein in the oral cavity. S.mutans is a major pathogen responsible for dental caries. Repeated challenge with S.mutans harboring the cnm gene encoding Cnm induced cerebral bleeding in stroke-prone spontaneously hypertensive rats. The purpose of this longitudinal study is to examine the relationship of cnm-positive S.mutans to the development of CMB. METHODS: We retrospectively investigated patients with stroke receiving oral microbiological examination and head 3T magnetic resonance imaging evaluations twice in the period 2014 to 2019, allowing >180-day interval. Patients with cnm-positive S.mutans were compared with those without. Quasi-Poisson regression models were used to explore associations between cnm-positive S.mutans and the increase in number of CMB between the 2 magnetic resonance imaging scans. RESULTS: A total of 111 patients were identified; 21 (19%) with cnm-positive S.mutans and 90 (81%) without. Clinical history, including blood pressure and the use of antithrombotic agents, were comparable between the 2 groups. New CMB were more commonly observed in patients with cnm-positive S.mutans (52% versus 23%; P=0.008). The incidence of CMB was significantly higher in the group with cnm-positive S.mutans, especially in deep areas, (incidence rate ratios [95% CI], 5.1 [1.9-13.6] for CMB in any brain region; 15.0 [5.4-42.0] for deep CMB), which persisted after adjusting for age, sex, hypertension, and renal impairment (4.7 [1.8-11.9] for CMB in any brain region; 13.9 [4.3-44.5] for deep CMB). CONCLUSIONS: This study demonstrates that cnm-positive S.mutans is associated with an increased incidence of CMB. Treatment for cnm-positive S.mutans infection may be a novel microbiota-based therapeutic approach for stroke and cognitive impairment.


Assuntos
Adesinas Bacterianas/genética , Proteínas de Transporte/genética , Portador Sadio/epidemiologia , Hemorragia Cerebral/epidemiologia , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Infecções Estreptocócicas/epidemiologia , Streptococcus mutans/genética , Idoso , Idoso de 80 Anos ou mais , Portador Sadio/microbiologia , Hemorragia Cerebral/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Feminino , Humanos , Incidência , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Estudos Retrospectivos , Infecções Estreptocócicas/microbiologia , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
8.
Int J Mol Sci ; 20(10)2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126115

RESUMO

Vascular risk factors, such as type 2 diabetes mellitus (T2DM), are associated with the increased risk of Alzheimer's disease. One of the common T2DM medications, dipeptidyl peptidase (DPP)-4 inhibitors, have a minimum risk for hypoglycemia and have recently been suggested to ameliorate ß-amyloid pathology. However, conflicting results have been reported regarding the effects of DPP-4 inhibition on cognitive function and tau pathology. Thus, we investigated whether inhibiting DPP-4 affects tau pathology and cognition in a mouse model of tauopathy with hyperglycemia. Male mice overexpressing the P301S mutant human microtubule-associated protein tau gene (PS19) were fed either a low or high-fat diet. PS19 mice were then administered either linagliptin, a DPP-4 inhibitor, or vehicle, from 6 weeks to 8 months of age. Linagliptin-treated mice exhibited higher levels of glucagon-like peptide-1 and decreased fasting blood glucose, compared with the vehicle-treated mice at 8 months. Linagliptin treatment significantly restored spatial reference memory and increased cerebral blood flow without affecting phosphorylation levels of tau or endothelial nitric oxide synthase (eNOS) in the brain. Linagliptin may ameliorate HFD-induced cognitive worsening in tauopathy, at least partially, by increasing cerebral perfusion via the eNOS-independent pathway.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Linagliptina/uso terapêutico , Tauopatias/tratamento farmacológico , Animais , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Hiperglicemia/complicações , Hiperglicemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tauopatias/complicações , Tauopatias/patologia
9.
Pharm Res ; 34(2): 333-351, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27864744

RESUMO

PURPOSE: Predicting target site drug concentration in the brain is of key importance for the successful development of drugs acting on the central nervous system. We propose a generic mathematical model to describe the pharmacokinetics in brain compartments, and apply this model to predict human brain disposition. METHODS: A mathematical model consisting of several physiological brain compartments in the rat was developed using rich concentration-time profiles from nine structurally diverse drugs in plasma, brain extracellular fluid, and two cerebrospinal fluid compartments. The effect of active drug transporters was also accounted for. Subsequently, the model was translated to predict human concentration-time profiles for acetaminophen and morphine, by scaling or replacing system- and drug-specific parameters in the model. RESULTS: A common model structure was identified that adequately described the rat pharmacokinetic profiles for each of the nine drugs across brain compartments, with good precision of structural model parameters (relative standard error <37.5%). The model predicted the human concentration-time profiles in different brain compartments well (symmetric mean absolute percentage error <90%). CONCLUSIONS: A multi-compartmental brain pharmacokinetic model was developed and its structure could adequately describe data across nine different drugs. The model could be successfully translated to predict human brain concentrations.


Assuntos
Acetaminofen/farmacocinética , Encéfalo/metabolismo , Morfina/farmacocinética , Animais , Barreira Hematoencefálica/metabolismo , Humanos , Masculino , Modelos Biológicos , Modelos Teóricos , Ratos , Ratos Wistar , Distribuição Tecidual/fisiologia
10.
J Toxicol Pathol ; 30(2): 169-175, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28458455

RESUMO

Spontaneous nephroblastoma is an uncommon tumor in laboratory rabbits. We recently encountered this tumor, and we describe its histological characteristics in this report. A male 3-year-old Japanese White rabbit (JW/kbs), maintained as a stock animal, suddenly showed poor condition and was found dead a few days later. At necropsy, a large mass was found that extended from one side of the renal pelvis. The cut surface of the mass was dark red in color and velvety to the touch. The kidney on the contralateral side was normal. Microscopically, the tumor mass consisted of biphasic components, which consisted of epithelial (tubular and glomerular) and blastemal (nodular) elements. No sarcomatous proliferation was observed. In addition, some of the tubules were lined by cells with a large amount of eosinophilic cytoplasm. The cells were confirmed as oncocytes by immunohistochemical and electron microscopic examinations. The present case was therefore diagnosed as a nephroblastoma with oncocytic differentiation.

11.
J Neurosci ; 35(9): 3915-28, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25740520

RESUMO

Subcortical white matter (WM) is a frequent target of ischemic injury and extensive WM lesions are important substrates of vascular cognitive impairment (VCI) in humans. However, ischemic stroke rodent models have been shown to mainly induce cerebral infarcts in the gray matter, while cerebral hypoperfusion models show only WM rarefaction without infarcts. The lack of animal models consistently replicating WM infarct damage may partially explain why many neuroprotective drugs for ischemic stroke or VCI have failed clinically, despite earlier success in preclinical experiments. Here, we report a novel animal model of WM infarct damage with cognitive impairment can be generated by surgical implantation of different devices to the right and left common carotid artery (CCA) in C57BL/6J mice. Implantation of an ameroid constrictor to the right CCA resulted in gradual occlusion of the vessel over 28 d, whereas placement of a microcoil to the left CCA induced ∼50% arterial stenosis. Arterial spin labeling showed a gradual reduction of cerebral blood flow over 28 d post operation. Such reductions were more marked in the right, compared with the left, hemisphere and in subcortical, rather than the cortical, areas. Histopathological analysis showed multiple infarct damage in right subcortical regions, including the corpus callosum, internal capsule, hippocampal fimbria, and caudoputamen, in 81% of mice. Mice displaying such damage performed significantly poorer in locomotor and cognitive tests. The current mouse model replicates the phenotypes of human subcortical VCI, including multiple WM infarcts with motor and cognitive impairment.


Assuntos
Infarto Cerebral/patologia , Infarto Cerebral/psicologia , Demência/patologia , Demência/psicologia , Animais , Pressão Sanguínea/fisiologia , Isquemia Encefálica/patologia , Isquemia Encefálica/psicologia , Circulação Cerebrovascular , Constrição Patológica , Demência Vascular/patologia , Demência Vascular/psicologia , Frequência Cardíaca , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Equilíbrio Postural , Acidente Vascular Cerebral Lacunar/patologia , Acidente Vascular Cerebral Lacunar/psicologia
12.
Bioorg Med Chem ; 24(16): 3727-33, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27325447

RESUMO

Isomeric iodinated derivatives of nimesulide, with an iodine substituent on the phenoxy ring, were prepared with the aim of identifying potential candidate compounds for the development of imaging agents targeting cyclooxygenase-2 (COX-2) in the brain. Both the experimental logP7.4 and pKa values for these iodinated analogs were in the acceptable range for passive brain penetration. The para-iodo-substituted analog was a more potent and selective COX-2 inhibitor than nimesulide, with a potency that was comparable to the reference drug, celecoxib. Iodination at the ortho- or meta-position of the phenoxy ring was associated with a substantial loss of COX-2 inhibitory activity. Transport studies across Caco-2 cell monolayers in the presence and absence of a P-glycoprotein (P-gp) inhibitor, verapamil, indicated that the para-iodo-substituted analog was not a P-gp transport substrate; this feature is a prerequisite for potential in vivo brain imaging compounds. The para-iodo-substituted analog of nimesulide appears to be an attractive candidate for the development of radioiodine-labeled tracers for in vivo brain imaging of COX-2 levels.


Assuntos
Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Animais , Encéfalo/metabolismo , Células CACO-2 , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/farmacocinética , Humanos , Isomerismo , Camundongos , Camundongos Endogâmicos BALB C , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfonamidas/síntese química , Sulfonamidas/farmacocinética
13.
J Stroke Cerebrovasc Dis ; 25(8): e128-30, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241575

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary and progressive small-vessel disease caused by NOTCH3 mutations, pathologically characterized by the degeneration of vascular mural cells, white matter changes, and ischemic strokes. Recently, dysautoregulation has received increasing attention regarding the pathogenesis of stroke in CADASIL. Here, we report a CADASIL case with a novel Cys323Trp mutation in the NOTCH3 gene, which suggests a close relationship between hemodynamic factors and clustering of cerebral infarctions in CADASIL. A 47-year-old male patient presented with internal border-zone infarcts in the bilateral hemispheres and was diagnosed with CADASIL by the presence of granular osmiophilic material and the accumulation of the Notch3 extracellular domain around small vessels. A literature review revealed 7 reports of similar CADASIL cases with clustering of cerebral infarctions related to blood pressure fluctuations. Not only large-artery stenosis but also small-vessel pathologies potentiate watershed infarctions, which might be triggered by hemodynamic fluctuation due to cerebral dysautoregulation.


Assuntos
Infarto Encefálico/etiologia , CADASIL/complicações , CADASIL/genética , Mutação/genética , Receptor Notch3/genética , CADASIL/diagnóstico por imagem , Cisteína/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Triptofano/genética
14.
Shinrigaku Kenkyu ; 87(2): 133-43, 2016 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-27476263

RESUMO

We tested possible intrapersonal effects of a sigh as a psychological "resetter/rebooter." Fifty-eight undergraduates were randomly assigned to a sigh or a normal exhalation (control) group. We asked participants on each task to model the experimenter demonstrating how to exhale air into a small plastic bag for breathing manipulation under the pretext that we were interested in the exhaled gas in stressful situations. Results revealed that the sigh group did not experience more relief (as shown by prolonged reaction time) after exposure to threat stimuli, but showed more persistence on a highly-difficult puzzle task (p = .03, d = .62) and more willingness to continue working on a monotonous task (p < .10, d = .48), than the normal exhalation group. A sigh may have an adaptive function to motivate further work; although it may not induce relief--suggesting that a "sigh of refresh" is a voluntary but a "sigh of relief" is an involuntary response.


Assuntos
Logro , Expiração/fisiologia , Motivação , Análise e Desempenho de Tarefas , Tédio , Feminino , Humanos , Masculino , Motivação/fisiologia , Adulto Jovem
16.
Bioorg Med Chem ; 23(21): 6807-14, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26455657

RESUMO

Nimesulide analogs bearing a methoxy substituent either at the ortho-, meta- or para-position on the phenyl ring, were designed, synthesized, and evaluated for potential as radioligands for brain cyclooxygenase-2 (COX-2) imaging. The synthesis of nimesulide and regioisomeric methoxy analogs was based on the copper-mediated arylation of phenolic derivatives for the construction of diaryl ethers. These isomeric methoxy analogs displayed lipophilicity similar to that of nimesulide itself, as evidenced by their HPLC logP7.4 values. In vitro inhibition studies using a colorimetric COX (ovine) inhibitor-screening assay demonstrated that the para-methoxy substituted analog retains the inhibition ability and selectivity observed for parent nimesulide toward COX-2 enzyme, whereas the meta- and ortho-methoxy substituents detrimentally affected COX-2-inhibition activity, which was further supported by molecular docking studies. Bidirectional transport cellular studies using Caco-2 cell culture model in the presence of the P-glycoprotein (P-gp) inhibitor, verapamil, showed that P-gp did not have a significant effect on the efflux of the para-methoxy substituted analog. Further investigations using the radiolabeled form of the para-methoxy substituted analog is warranted for in vivo characterization.


Assuntos
Meios de Contraste/síntese química , Inibidores de Ciclo-Oxigenase 2/síntese química , Ciclo-Oxigenase 2/metabolismo , Sulfonamidas/química , Encéfalo/enzimologia , Células CACO-2 , Domínio Catalítico , Meios de Contraste/química , Meios de Contraste/metabolismo , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/metabolismo , Humanos , Isomerismo , Conformação Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Sulfonamidas/síntese química , Sulfonamidas/metabolismo
17.
Cell Biochem Funct ; 33(2): 73-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25663666

RESUMO

Acquired radioresistance of cancer cells interferes with radiotherapy and increases the probability of cancer recurrence. HepG2-8960-R, which is one of several clinically relevant radioresistant (CRR) cell lines, has a high tolerance to the repeated clinically relevant doses of X-ray radiation. In this study, HepG2-8960-R had slightly lower cell proliferation ability than HepG2 in the presence of FBS. In particular, epidermal growth factor (EGF) hardly enhanced cell proliferation and DNA synthesis in HepG2-8960-R. Additionally, EGF could not induce the activation of Erk1/2, because the expression of EGF receptor (EGFR) protein decreased in HepG2-8960-R in accordance with the methylation of the EGFR promoter region. Therefore, cetuximab did not inhibit HepG2-8960-R cell proliferation. Our study showed that HepG2-8960-R had radioresistant and cetuximab-resistant abilities.


Assuntos
Carcinoma Hepatocelular/radioterapia , Proliferação de Células , Fator de Crescimento Epidérmico/metabolismo , Neoplasias Hepáticas/radioterapia , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Cetuximab , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Metilação , Regiões Promotoras Genéticas , Tolerância a Radiação
18.
Stroke ; 45(11): 3403-11, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25213338

RESUMO

BACKGROUND AND PURPOSE: Silent information regulator 2 homolog 1 (SIRT1) is a protein deacetylase that has been reported to suppress neurodegenerative and cardiovascular diseases in model organisms. We hypothesized that neurovascular protection is one of the diverse actions of SIRT1. This study was designed to determine whether SIRT1 protects against the consequences of cerebral hypoperfusion in vivo. METHODS: Sirt1-overexpressing (Sirt1-Tg) mice driven by a prion promoter and their wild-type littermates were subjected to bilateral common carotid artery stenosis using external microcoils. Using Sirt1-Tg mice, we assessed the effect of SIRT1 on cerebral blood flow, cerebral angioarchitecture, histological and ultrastructural changes, and spatial working memory at several time points. We also evaluated the effects of preadministration of SIRT1 inhibitors or endothelial nitric oxide synthase inhibitors on cerebral blood flow after bilateral common carotid artery stenosis in Sirt1-Tg mice. Levels of acetylated and nonacetylated endothelial nitric oxide synthase were measured semiquantitatively with immunoblotting. RESULTS: Cerebral hypoperfusion induced by bilateral common carotid artery stenosis caused memory impairment and histological changes in wild-type littermates. However, these phenotypes were rescued in Sirt1-Tg mice, where cerebral blood flow was maintained even poststenosis. Electron microscopic analyses showed irregularities in the vascular endothelia, such as tight junction openings in wild-type mice, which were absent in Sirt1-Tg littermates. Brain endothelial nitric oxide synthase was acetylated after cerebral hypoperfusion in wild-type littermates but remained unacetylated in Sirt1-Tg mice. Moreover, treatment with SIRT1 inhibitors and endothelial nitric oxide synthase inhibitors abolished the vasculoprotective effects of SIRT1. CONCLUSIONS: Our results indicate that neurovascular endothelial SIRT1 potentiation upregulates the nitric oxide system and counters cerebral hypoperfusion injury. This novel cerebral blood flow-preserving mechanism offers potential molecular targets for future therapeutic intervention.


Assuntos
Lesões Encefálicas/metabolismo , Lesões Encefálicas/prevenção & controle , Circulação Cerebrovascular/fisiologia , Óxido Nítrico Sintase Tipo III/biossíntese , Sirtuína 1/biossíntese , Acetilação , Animais , Lesões Encefálicas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
19.
Neuropathol Appl Neurobiol ; 40(5): 591-602, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23844775

RESUMO

BACKGROUND: Magnetic resonance imaging indicates diffuse white matter (WM) changes are associated with cognitive impairment in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). We examined whether the distribution of axonal abnormalities is related to microvascular pathology in the underlying WM. METHODS: We used post-mortem brains from CADASIL subjects and similar age cognitively normal controls to examine WM axonal changes, microvascular pathology, and glial reaction in up to 16 different regions extending rostro-caudally through the cerebrum. Using unbiased stereological methods, we estimated length densities of affected axons immunostained with neurofilament antibody SMI32. Standard immunohistochemistry was used to assess amyloid precursor protein immunoreactivity per WM area. To relate WM changes to microvascular pathology, we also determined the sclerotic index (SI) in WM arterioles. RESULTS: The degree of WM pathology consistently scored higher across all brain regions in CADASIL subjects (P<0.01) with the WM underlying the primary motor cortex exhibiting the most severe change. SMI32 immunoreactive axons in CADASIL were invariably increased compared with controls (P<0.01), with most prominent axonal abnormalities observed in the frontal WM (P<0.05). The SIs of arterioles in CADASIL were increased by 25-45% throughout the regions assessed, with the highest change in the mid-frontal region (P=0.000). CONCLUSIONS: Our results suggest disruption of either cortico-cortical or subcortical-cortical networks in the WM of the frontal lobe that may explain motor deficits and executive dysfunction in CADASIL. Widespread WM axonal changes arise from differential stenosis and sclerosis of arterioles in the WM of CADASIL subjects, possibly affecting some axons of projection neurones connecting to targets in the subcortical structures.


Assuntos
Axônios/patologia , CADASIL/patologia , Lobo Frontal/patologia , Substância Branca/patologia , Adulto , Idoso , Precursor de Proteína beta-Amiloide/metabolismo , Axônios/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , CADASIL/metabolismo , Feminino , Lobo Frontal/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/patologia , Substância Branca/irrigação sanguínea , Substância Branca/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-38874672

RESUMO

The maximum blood flow velocity through the aortic valve (AVmax) using Doppler transthoracic echocardiography (TTE) is important in assessing the severity of aortic stenosis (AS). The right parasternal (RP) approach has been reported to be more useful than the apical approach, but the anatomical rationale has not been studied. We aimed to clarify the influence of the angle formed by the ascending aorta and left ventricle on Doppler analysis by TTE (Sep-Ao angle) and three-dimensional multidetector computed tomography (3D-MDCT) in patients with AS. A total of 151 patients evaluated using the RP approach and 3D-MDCT were included in this study. The Sep-Ao angle determined using TTE was compared with that determined using 3D-MDCT analysis. In MDCT analysis, the left ventricular (LV) axis was measured in two ways and the calcification score was calculated simultaneously. The Sep-Ao angle on TTE was consistent with that measured using 3D-MDCT. In patients with an acute Sep-Ao angle, the Doppler angle in the apical approach was larger, potentially underestimating AVmax. Multivariate analysis revealed that an acute Sep-Ao angle, large Doppler angle in the apical approach, smaller Doppler angle in the RP approach, and low aortic valve calcification were independently associated with a higher AVmax in the RP approach than in the apical approach. The Sep-Ao angle measured using TTE reflected the 3D anatomical angle. In addition to measurements using the RP approach, technical adjustments to minimize the Doppler angle to avoid bulky calcification should always be noted for accurate assessment.

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