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1.
J Am Chem Soc ; 140(6): 2196-2205, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29323891

RESUMO

The transition-metal-catalyzed C-H arylation of aromatic hydrocarbons represents a useful and ideal method for the production of biaryls and multiarylated aromatic compounds. We have previously reported the palladium-catalyzed direct C-H arylation of polycyclic aromatic hydrocarbons, such as phenanthrene, pyrene, and corannulene with various organosilicon, -borane, and -germanium compounds. In these reactions, o-chloranil proved to be an essential and unique promoter (stoichiometrically as an oxidant) and arylation occurred exclusively at the K-region. Herein, we report our mechanistic investigation of Pd/o-chloranil catalysis in C-H arylation of phenanthrene with trimethylphenylsilane by computational calculations. The results revealed that C-H arylation occurs through a sequence of transmetalation, carbometalation, and trans-ß-hydrogen elimination steps. In addition, the triple role of o-chloranil as a ligand, oxidant, and base is also elucidated.

2.
Phys Chem Chem Phys ; 17(14): 8638-41, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25759865

RESUMO

A dinuclear copper(II) complex of 3,5-diamino-1,2,4-triazole is one of the highly active copper-based catalysts for the oxygen reduction reaction (ORR) in basic solutions. Our in situ X-ray absorption near edge structure measurements revealed that deprotonation of the triazole ligand might cause coordination geometrical changes, resulting in the enhancement of the ORR activity.

3.
J Crohns Colitis ; 17(3): 369-378, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36149832

RESUMO

BACKGROUND AND AIMS: Previous studies conducted in Europe suggested that darvadstrocel, a suspension of expanded, allogeneic, adipose-derived, mesenchymal stem cells, is safe and effective for treatment-refractory complex perianal fistulas in patients with Crohn's disease. The aim of this study was to evaluate the efficacy and safety of darvadstrocel for the treatment of complex perianal fistulas in Japanese adults with Crohn's disease. METHODS: This is a phase 3, open-label, single-arm study conducted at nine sites in Japan. Adult patients with non-active or mildly active Crohn's disease and complex perianal fistulas received a single 24-mL intralesional injection of darvadstrocel [120 × 106 cells]. The primary endpoint was combined remission (clinically confirmed closure of all treated external openings that were draining at screening, and absence of collections >2 cm, [confirmed by magnetic resonance imaging] among treated fistulas) at Week 24. RESULTS: Between March 6, 2019 and February 1, 2021, 22 patients received darvadstrocel and completed the 52-week follow-up. The proportion of patients achieving combined remission at Week 24 was 59.1% (95% confidence interval [CI], 38.5-79.6). The effect was maintained at Week 52, with 68.2% [95% CI, 48.7-87.6] of patients achieving combined remission. Treatment-related adverse events included: one [4.5%] patient with worsening of Crohn's disease and diarrhoea, and one [4.5%] patient with blood bilirubin increase. No new safety findings were identified in this study. CONCLUSIONS: The efficacy and tolerability of darvadstrocel in Japanese adult patients with treatment-refractory complex perianal fistulas in Crohn's disease were similar to those observed in the previous European study. ClinicalTrials.gov number, NCT03706456.


Assuntos
Doença de Crohn , Transplante de Células-Tronco Mesenquimais , Fístula Retal , Humanos , Adulto , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Resultado do Tratamento , População do Leste Asiático , Fístula Retal/etiologia , Fístula Retal/terapia , Fístula Retal/diagnóstico , Transplante de Células-Tronco Mesenquimais/métodos
4.
J Stomatol Oral Maxillofac Surg ; 124(5): 101516, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37236352

RESUMO

OBJECTIVE: To quantify facial swelling at 1 week after Le Fort I osteotomy and bilateral sagittal splitting ramus osteotomy in Class III patients and to identify factors contributing to the swelling based on clinical, morphologic, and surgical variables. STUDY DESIGN: Data from 63 patients were examined in this single-center, retrospective study. Facial swelling was quantitatively measured by superimposing computed tomography data taken in the supine position at 1 week and 1 year postoperatively and extracting the area of maximum intersurface distance. Age, sex, body mass index, thickness of subcutaneous tissue, and of masseter muscle, maxillary length (A-VRP), mandibular length (B-VRP), and posterior maxillary height (U6-HRP), surgical movement (ΔA-VRP, ΔB-VRP, ΔU6-HRP), drainage method, and usage of facial bandages were examined. Multiple regression analysis was performed using the above factors. RESULTS: The median swelling at 1 week postoperatively was 8.35 IQR (5.99-11.47) mm. Multiple regression analysis revealed three factors that were significantly associated with facial swelling: Use of postoperative facial bandages (P=0.03), masseter muscle thickness (P=0.03), and ΔB-VRP (P=0.04). CONCLUSION: Absence of a facial bandage, thin masseter muscle, and large horizontal mandibular movement are risk factors for facial swelling at 1 week postoperatively.


Assuntos
Angioedema , Cirurgia Ortognática , Humanos , Estudos Retrospectivos , Face/cirurgia , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-36535887

RESUMO

OBJECTIVE: The objective was to evaluate stiffness as a prognostic factor for tongue squamous cell carcinoma (TSCC). STUDY DESIGN: This retrospective study included 55 patients with pathologic stage pT1 or T2 TSCC with muscle-layer invasion who underwent preoperative strain elastography of the tongue, followed by surgery, as the primary treatment modality at our cancer center. The stiffness of TSCC was semi-quantified as the ratio of the strain value of a non-tumor site to the strain value of the tumor site (strain ratio [SR]) using ultrasound strain elastography findings. RESULTS: SR cutoff values that maximized the significance of the difference for prognosis of delayed cervical lymph node metastasis (DCLNM) and overall survival (OS) were 7.10 and 7.49, respectively. In univariate analysis, SR, age, depth of invasion, pT stage, and perineural invasion were significant risk factors for DCLNM, whereas SR, sex, and DCLNM were identified as having an association with OS. In multivariate analysis, SR was a significant risk factor for DCLNM (hazard ratio [HR] = 3.102; P = .021) and a non-significant but relevant risk factor for OS (HR = 8.774; P = .073). Age also had an association with OS (HR = 0.382; 95% CI 0.127-1.152; P = .088). CONCLUSION: Tongue stiffness is a prognostic factor in patients with pT1/T2 TSCC with muscle-layer invasion. SR values >7.10 indicate a poor prognosis, thereby warranting a strict follow-up regimen in these cases.


Assuntos
Carcinoma de Células Escamosas , Técnicas de Imagem por Elasticidade , Neoplasias da Língua , Humanos , Carcinoma de Células Escamosas/patologia , Prognóstico , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos , Língua
6.
Masui ; 61(1): 64-7, 2012 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-22338862

RESUMO

BACKGROUND: Although Airtraq (ATQ) is well accepted as a useful device for tracheal intubation especially in cases of difficult airway management, we sometimes encounter difficulty in insertion of a tracheal tube along the blade of ATQ across the vocal cord in spite of ATQ assistance. Gum Elastic Bougie (GEB) is well known as a practical device for intubation assistance with Macintosh laryngoscope. We studied the efficacy of GEB for intubation with ATQ. METHODS: One-hundred-forty one patients scheduled for general anesthesia, ASA physical status 1 or 2, were allocated into two groups randomly; patients intubated with ATQ without GEB (n = 70), and those with ATQ with GEB (n = 71). Twenty anesthegiologists were assinged to them evenly according to their experience. We measured the time they needed for intubation. RESULTS: The combinational advantage of ATQ and GEB was not significantly proved among board certified anesthesiologist. However, among non-board-certified anesthesiologist group, the time needed for successful intubation was significantly shorter with combined use of ATQ and GEB. CONCLUSIONS: For the people with less experience of intubation, GEB is useful assistance for intubation with ATQ. It was concluded that the combined use of ATQ and GEB is a simple and effective process for ordinary doctors or paramedics.


Assuntos
Intubação Intratraqueal/instrumentação , Laringoscópios , Anestesia Geral , Humanos , Intubação Intratraqueal/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-36244954

RESUMO

OBJECTIVE: To investigate morphologic and surgical risk factors causing neurosensory disturbances (NSDs) after bilateral sagittal split osteotomy (BSSO). STUDY DESIGN: A total of 237 patients (with 474 sides) who underwent BSSO were followed up for 1 year. Parameters examined included age, sex, asymmetry, mandibular movement direction, mandible cutting devices, split type, intraoperative exposure of the inferior alveolar nerve (IAN), contact between the IAN and screw, distance between mandibular canal and inner surface of the cortical bone (distance A), distance from lateral osteotomy to mental foramen (distance B), and NSD at 1 year postoperatively. RESULTS: NSD was observed in 62 (13.1%) sides of 51 patients. Exploratory factor analysis determined 4 factors (factor 1: distance A; factor 2: direction of mandibular movement; factor 3: distance B and cutting devices; factor 4: IAN exposure). Logistic regression analysis was performed using the above factors and age, sex, and asymmetry, making a total of 7 variables. Age, factor 1, and factor 4 were significant predictors of NSD. CONCLUSIONS: Advanced age, close distance between mandibular canal and inner surface of the cortical bone, and IAN intraoperative exposure are risk factors for NSD 1 year postoperatively. Cases at high risk for NSD must be treated with great care.


Assuntos
Fatores de Risco , Humanos
8.
Oral Radiol ; 38(2): 278-287, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34302572

RESUMO

OBJECTIVES: To evaluate the stiffness of tongue squamous cell carcinoma (TSCC) using ultrasound strain elastography, a relatively new sonographic imaging technique, and to identify the factors that affect this stiffness. METHODS: We treated 62 patients diagnosed with muscle invasive TSCC, who were treated at the department of oral surgery of our institution. Each patient's tumor stiffness was semi-quantified according to the ratio of cancer to tongue muscle strain measured using ultrasound strain elastography (the strain ratio). Histopathological diagnosis was made on the same section as the ultrasound strain elastography. We set the following histopathological parameters: cancer cell content in the tumor area (%CCC), collagen fiber content in the tumor area (%CFC), and tumor-infiltrating inflammatory cell content in the stromal compartment (%TIIC). Spearman's rank correlation (rs) was used to assess correlations, and P values < 0.05 were considered significant. RESULTS: The mean strain ratio was 9.7 ± 9.8. The mean %CCC was 38.4 ± 11.3%, and % CFC was 31.1 ± 7.8%, % TIICs was 19.9 ± 8.9%. Log (strain ratio) by ultrasound strain elastography was positively correlated with %CFC (rs = 0.379, P = 0.024). %CFC was negatively correlated with %TIICs (rs = - 0.318, P = 0.012). No correlations were observed between other clinico-histopathological factors and either strain ratio, or %CFC. CONCLUSION: The strain ratio of the cancer to the strain of the tongue muscle measured through ultrasound strain elastography positively correlates with the collagen fiber content of the tumor area.


Assuntos
Carcinoma de Células Escamosas , Técnicas de Imagem por Elasticidade , Neoplasias da Língua , Carcinoma de Células Escamosas/diagnóstico por imagem , Colágeno , Técnicas de Imagem por Elasticidade/métodos , Humanos , Língua/diagnóstico por imagem , Neoplasias da Língua/diagnóstico por imagem
9.
Bioorg Med Chem Lett ; 21(19): 5901-4, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21843938

RESUMO

Urolithin A is a major metabolite produced by rats and humans after consumption of pomegranate juice or pure ellagitannin geraniin. In this study, we investigated the anti-inflammatory effect of urolithin A on carrageenan-induced paw edema in mice. The volume of paw edema was reduced at 1h after oral administration of urolithin A. In addition, plasma in treated mice exhibited significant oxygen radical antioxidant capacity (ORAC) scores with high plasma levels of the unconjugated form at 1h after oral administration of urolithin A. These results indicate strong associations among plasma urolithin A levels, the plasma ORAC scores, and anti-inflammatory effects and may help explain a mechanism by which ellagitannins confer protection against inflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Cumarínicos/farmacologia , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/metabolismo , Cumarínicos/administração & dosagem , Cumarínicos/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Sequestradores de Radicais Livres/análise , Glucosídeos , Glucuronídeos/metabolismo , Humanos , Taninos Hidrolisáveis/metabolismo , Lythraceae , Camundongos , Camundongos Endogâmicos ICR , Ratos
10.
Hiroshima J Med Sci ; 60(2): 37-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21970186

RESUMO

Patients on long-term hemodialysis are at risk of developing malnutrition,and poor nutrient intake is an important factor in this. In the present case, we encountered a 55-year-old Japanese woman with end-stage renal failure and a past history of schizophrenia. Severe systemic edema was observed. Hemodialysis was started, but after one year she suddenly became unable to consume food orally, despite provision of a dietary plan by the nutrition support team (NST). Tube feeding was eventually implemented. Because the systemic edema did not improve, we decided to remove body fluid by intense hemodialysis. Hypotension was often observed during this hemodialysis, requiring dopamine. Over approximately 2 months, the patient's dry weight fell from 73 kg to 62 kg, the patient's activity improved and she became able to eat orally again, allowing tube feeding to be stopped. Although the reason for the sudden anorexia has not been clarified, tube feeding and dry weight control was successful in the treatment of this malnourished hemodialysis patient.


Assuntos
Edema/terapia , Nutrição Enteral , Falência Renal Crônica/terapia , Desnutrição/terapia , Diálise Renal , Atividades Cotidianas , Dopamina/uso terapêutico , Edema/etiologia , Edema/fisiopatologia , Feminino , Humanos , Hipotensão/tratamento farmacológico , Hipotensão/etiologia , Desnutrição/etiologia , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Estado Nutricional , Diálise Renal/efeitos adversos , Simpatomiméticos/uso terapêutico , Resultado do Tratamento , Redução de Peso
11.
J Clin Virol ; 44(1): 15-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18952495

RESUMO

BACKGROUND: Viral resistance to antiviral drugs can cause serious complications in immunosuppressed patients. We isolated from an allogeneic stem cell transplant (SCT) recipient an antiviral-resistant human herpesvirus 6 (HHV-6) strain with mutations that caused amino acid substitutions. OBJECTIVE: To study the impact of mutations in the U38 and U69 genes of the ganciclovir (GCV)-resistant HHV-6 strain associated with the death of the SCT recipient. STUDY DESIGN: Viruses were obtained from blood taken during symptomatic disease. Mutations in the genes for U69 protein kinase and U38 DNA polymerase were analyzed and the effects of the U69 mutations on GCV resistance were assayed using a recombinant baculovirus system. RESULTS: Increasing HHV-6 antigenemia occurred after 2-3 months of preemptive GCV therapy, followed by symptomatic HHV-6 disease that ended in fatal fungus-related septic shock. The HHV-6 strain isolated from the patient was 100-fold more resistant to GCV than was a wild-type strain. New mutations were found in HHV-6 genes U38 (P462S and A565V) and U69 (L202I and L213I). The mutation of U38 P462S corresponds to a mutation in the UL54 gene (P522S) of a GCV-resistant HCMV. The U69 mutations did not alter GCV sensitivity in baculovirus GCV-resistant assay system. CONCLUSIONS: Drug-resistant mutations arising during preemptive therapy may complicate post-transplant HHV-6 disease in SCT recipients. The increased copy number during GCV treatment of this new GCV-resistant HHV-6 strain correlated with mutations in the U69 and U38 genes. Since the kinase mutation did not alter sensitivity to GCV when tested in the in vitro system, it is likely that the substitutions in the polymerase related to GCV resistance.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Ganciclovir/farmacologia , Herpesvirus Humano 6/efeitos dos fármacos , Herpesvirus Humano 6/isolamento & purificação , Infecções por Roseolovirus/virologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Animais , Baculoviridae/genética , Linhagem Celular , Pré-Escolar , DNA Viral/química , DNA Viral/genética , Evolução Fatal , Herpesvirus Humano 6/genética , Humanos , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Alinhamento de Sequência , Análise de Sequência de DNA , Transplante de Células-Tronco/efeitos adversos , Transplante , Proteínas não Estruturais Virais/genética
12.
Pediatr Dermatol ; 26(5): 597-600, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19840319

RESUMO

We describe a 10-year-old girl who presented with bizarre purpura. Both congenital and autoimmune hemorrhagic disorders were excluded based on her past medical history and physical and laboratory findings. Child abuse was also ruled out as purpura continued to develop after child-family separation. Histologic examination of the skin lesions revealed disruption of collagen fiber bundles. This finding indicated application of external force, leading to a definitive diagnosis of factitious purpura. Although it is very rare in school-age children, the diagnosis of factitious purpura should be included in the differential diagnosis of purpura in children. Histologic analysis of skin biopsies may aid in establishing the diagnosis.


Assuntos
Transtornos Autoinduzidos/complicações , Transtornos Autoinduzidos/patologia , Púrpura/etiologia , Púrpura/patologia , Comportamento Autodestrutivo/complicações , Biópsia , Criança , Diagnóstico Diferencial , Feminino , Humanos , Dermatopatias/etiologia , Dermatopatias/patologia , Estresse Psicológico/complicações
13.
Am J Perinatol ; 26(8): 583-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19399703

RESUMO

We describe herein the case of a 3-day-old male neonate with umbilical arteriovenous malformation showing umbilical hemorrhage. The patient was born after 38 weeks and 3 days of gestation with a birth weight of 2784 g. Sudden massive umbilical hemorrhage occurred on day 3. Cardiopulmonary arrest developed, but the patient was successfully rescued by immediate cardiopulmonary resuscitation. An umbilical venous catheter was inserted for blood access. However, umbilical hemorrhage continued and hemostasis was difficult. Congenital bleeding disorders were excluded based on laboratory findings. Ultrasonography on day 15 revealed a mass with rich blood supply directly under the umbilicus. Umbilical arteriovenous malformation was suspected from abdominal contrast-enhanced computed tomography on day 17. Excision of the arteriovenous malformation was performed on day 29. The mass was connected to three arteries including the umbilical arteries, with the umbilical vein flowing out from the mass. Umbilical arteriovenous malformation was diagnosed from evidence during the operation and pathological findings. Umbilical arteriovenous malformations are rare and often discovered by heart failure symptoms, but rare cases present with umbilical bleeding, as in this report. Umbilical arteriovenous malformation must be taken into consideration as along with congenital bleeding disorders when massive umbilical hemorrhage is identified.


Assuntos
Malformações Arteriovenosas/complicações , Hemorragia/etiologia , Choque Hemorrágico/etiologia , Artérias Umbilicais/anormalidades , Veias Umbilicais/anormalidades , Malformações Arteriovenosas/cirurgia , Hemorragia/diagnóstico , Humanos , Recém-Nascido , Masculino
14.
Drug Saf ; 42(11): 1311-1327, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31654243

RESUMO

The dipeptidyl peptidase-4 inhibitor (DPP-4i) alogliptin is an oral, antidiabetic treatment that is approved in many countries to treat patients with type 2 diabetes mellitus (T2DM), including the USA, Europe, and Japan. Alogliptin is efficacious both as monotherapy and as add-on/combination therapy with other commonly prescribed T2DM treatments, such as metformin and pioglitazone. Overall, alogliptin is well-tolerated in patients with T2DM, including older patients, those with renal and/or hepatic impairment, and those at high risk of cardiovascular events. There is a low risk of hypoglycemia, weight gain, acute pancreatitis, and gastrointestinal adverse events with alogliptin treatment, as demonstrated in long-term trials (lasting up to 4.5 years) and in a real-world setting. Additionally, alogliptin has a generally favorable or similar safety profile in comparison to other antidiabetic agents (metformin, thiazolidinediones, sulfonylureas, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors, α-glucosidase inhibitors, and insulin). However, further evaluation would be required to determine the mechanism and effect of alogliptin on heart failure, bullous pemphigoid, and inflammatory bowel disease. Of note, due to the ethnic diversity in the epidemiology of T2DM, alogliptin has been shown to be more efficacious in Asian patients than in non-Asian patients with T2DM, but with a similar tolerability profile. These data indicate that DPP-4is, including alogliptin, are important treatment options, especially for Asian patients with T2DM, for whom they have potential as a first-line therapy. This benefit-risk assessment aims to place alogliptin within the current armamentarium of T2DM and aid physicians when choosing optimal diabetes treatment for their patients.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Dipirona/uso terapêutico , Hipoglicemiantes/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Dipirona/efeitos adversos , Humanos , Hipoglicemiantes/efeitos adversos , Medição de Risco
16.
Curr Biol ; 13(3): 230-5, 2003 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-12573219

RESUMO

O(2) photoreduction by photosynthetic electron transfer, the Mehler reaction, was observed in all groups of oxygenic photosynthetic organisms, but the electron transport chain mediating this reaction remains unidentified. We provide the first evidence for the involvement of A-type flavoproteins that reduce O(2) directly to water in vitro. Synechocystis sp. strain PCC 6803 mutants defective in flv1 and flv3, encoding A-type flavoproteins, failed to exhibit O(2) photoreduction but performed normal photosynthesis and respiration. We show that the light-enhanced O(2) uptake was not due to respiration or photorespiration. After dark acclimation, photooxidation of P(700) was severely depressed in mutants Deltaflv1 and Deltaflv3 but recovered after light activation of CO(2) fixation, which gives P(700) an additional electron acceptor. Inhibition of CO(2) fixation prevented recovery but scarcely affected P(700) oxidation in the wild-type, where the Mehler reaction provides an alternative route for electrons. We conclude that the source of electrons for O(2) photoreduction is PSI and that the highly conserved A-type flavoproteins Flv1 and Flv3 are essential for this process in vivo. We propose that in cyanobacteria, contrary to eukaryotes, the Mehler reaction produces no reactive oxygen species and may be evolutionarily related to the response of anaerobic bacteria to O(2).


Assuntos
Cianobactérias/metabolismo , Flavoproteínas/genética , Luz , Oxigênio/metabolismo , Fotossíntese/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cianobactérias/genética , Inibidores Enzimáticos/metabolismo , Flavoproteínas/metabolismo , Iodoacetamida/metabolismo , Oxirredução , Oxigênio/química
17.
Neuroscience ; 362: 70-78, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-28844000

RESUMO

Amyloid-ß (Aß) production and clearance in the brain is a crucial focus of investigations into the pathogenesis of Alzheimer disease. Imbalance between production and clearance leads to accumulation of Aß. The important Aß-degrading enzymes in the brain are neprilysin (NEP) and insulin-degrading enzyme (IDE), and defective enzyme expression may facilitate Aß deposition in sporadic late-onset AD patients. It has been suggested that epigallocatechin gallate (EGCG), a member of the catechin family, might be an effective treatment for AD, because it has been shown to elevate NEP expression. Therefore, we examined whether catechins, which are functional components of common foods, could regulate the degradation of Aß by inducing NEP and IDE expression. We also investigated the role of catechins in activating intracellular signal transduction in astrocytes. Treatment of cultured rat astrocytes with EGCG significantly reduced the expression of NEP, but not IDE, in a concentration- and time-dependent manner. NEP expression in cultured astrocytes was suppressed by activation of extracellular signal-regulated kinase (ERK) and phosphoinositide 3-kinase (PI3K), and reduced NEP expression was accompanied by an increase of NEP release into the extracellular space (culture medium). Moreover, culture medium from EGCG-treated astrocytes facilitated the degradation of exogenous Aß. These results suggest that EGCG may have a beneficial effect on AD by activating ERK-and PI3K-mediated pathways in astrocytes, thus increasing astrocyte secretion of NEP and facilitating degradation of Aß.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Astrócitos/efeitos dos fármacos , Catequina/análogos & derivados , Neprilisina/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Astrócitos/enzimologia , Astrócitos/metabolismo , Catequina/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Isoflavonas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteólise/efeitos dos fármacos , Ratos Sprague-Dawley
18.
Org Lett ; 18(9): 1960-3, 2016 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-27058597

RESUMO

Encapsulation of highly emissive alkynylpyrenes with permethylated α-cyclodextrin (PM-α-CD) followed by capping reaction yielded alkynylpyrene-based [3]rotaxanes. The [3]rotaxane emitted only blue light of monomeric pyrene under various circumstances such as lipophilic, hydrophilic, and even condensed states and exhibited extremely high stability for UV irradiation. These properties would result because PM-α-CD, like bulletproof glass, protected the alkynylpyrene core from the attack of another excited alkynylpyrene and singlet oxygen generated by the energy transfer from the excited alkynylpyrene.

20.
J Dermatol ; 32(7): 523-33, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16335867

RESUMO

Tumor necrosis factor (TNF)-alpha is an important proinflammatory cytokine in contact hypersensitivity (CHS) reactions. Previous efforts to assay CHS in TNF-alpha gene-deficient (-/-) mice have demonstrated a significant reduction in ear skin weight at 24 h following challenge by oxazolone, although the mechanisms of this suppression have not been examined. To further characterize the impaired CHS during evolution of the elicitation phase in TNF-alpha -/- mice and to clarify its mechanisms, focusing on the roles of TNF-alpha and vascular endothelial growth factor (VEGF), we used an established method of CHS assay-sensitization and challenge by trinitrochlorobenzene (TNCB)- in TNF-alpha -/- and wild-type mice. We compared the histopathology of the sequential evolution of CHS between the two groups of mice and assessed both the extent of inflammatory cell infiltration and the degree of dilatation in dermal vessels labeled with CD31. We quantified the production of VEGF in the epidermis at specific time points by using a murine VEGF ELISA kit. The CHS reaction was markedly suppressed in TNF-alpha -/- mice at all time points of the elicitation phase. Histologically, in TNF-alpha -/- mice we observed diminished vascular permeability, reduced numbers of infiltrating inflammatory cells, neutrophils at 12 h, mononuclear cells and eosinophils at 24 h, and a decreased area of dilatation of vessels labeled with CD31. The level of epidermal VEGF in wild type mice increased rapidly after challenge and peaked at 24 h, paralleling the peak of ear swelling. In contrast, the peak level of epidermal VEGF in TNF-alpha -/- mice was significantly reduced. These results suggest that TNF-alpha plays an enhancing role in the elicitation phase of the CHS reaction. Diminished degrees of vascular permeability, dilatation of CD31+ vessels, and inflammatory cell infiltration in TNF-alpha -/- mice are likely to be the result of a lack of TNF-alpha and reduced production of epidermal VEGF.


Assuntos
Dermatite de Contato/fisiopatologia , Fator de Necrose Tumoral alfa/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Permeabilidade Capilar , Dermatite de Contato/metabolismo , Dermatite de Contato/patologia , Orelha Externa , Ensaio de Imunoadsorção Enzimática , Epiderme/metabolismo , Camundongos , Camundongos Knockout , Cloreto de Picrila , Pele/irrigação sanguínea , Fator de Necrose Tumoral alfa/genética , Vasodilatação
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