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1.
Phys Rev Lett ; 121(24): 242501, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30608744

RESUMO

The isospin character of p-n pairs at large relative momentum has been observed for the first time in the ^{16}O ground state. A strong population of the J,T=1,0 state and a very weak population of the J,T=0,1 state were observed in the neutron pickup domain of ^{16}O(p,pd) at 392 MeV. This strong isospin dependence at large momentum transfer is not reproduced by the distorted-wave impulse approximation calculations with known spectroscopic amplitudes. The results indicate the presence of high-momentum protons and neutrons induced by the tensor interactions in the ground state of ^{16}O.

2.
Faraday Discuss ; 206: 523-534, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28933473

RESUMO

Various types of piperidinium ionic liquids (ILs) equipped with an oxygen atom-containing alkyl side chain on the positively charged nitrogen atom were systematically synthesized and their physical properties investigated. The thermal stability, viscosity, electrochemical window, and ion conductivity were influenced significantly by changing the position of the oxygen atom in the alkyl chain. Although the lowest viscosity was recorded for 1-((2-methoxyethoxy)methyl)-1-methylpiperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1MEM][Tf2N]), 1-methyl-1-(2-propoxyethyl)piperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1PE][Tf2N]) can be recommended as the best IL as an electrolyte due to its low viscosity and high thermal and electrochemical stability among the seven ILs tested.

3.
J Clin Pharm Ther ; 42(5): 591-597, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28503837

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Anticoagulation therapy with warfarin requires periodic monitoring of prothrombin time-international normalized ratio (PT-INR) and adequate dose adjustments based on the data to minimize the risk of bleeding and thromboembolic events. In our hospital, we have developed protocol-based pharmaceutical care, which we called protocol-based pharmacotherapy management (PBPM), for warfarin therapy. The protocol requires pharmacists to manage timing of blood sampling for measuring PT-INR and warfarin dosage determination based on an algorithm. This study evaluated the efficacy of PBPM in warfarin therapy by comparing to conventional pharmaceutical care. METHODS: From October 2013 to June 2015, a total of 134 hospitalized patients who underwent cardiovascular surgeries received post-operative warfarin therapy. The early series of patients received warfarin therapy as the conventional care (control group, n=77), whereas the latter received warfarin therapy based on the PBPM (PBPM group, n=68). These patients formed the cohort of the present study and were retrospectively analysed. RESULTS: The indications for warfarin included aortic valve replacement (n=56), mitral valve replacement (n=4), mitral valve plasty (n=22) and atrial fibrillation (n=29). There were no differences in patients' characteristics between both groups. The percentage time in therapeutic range in the first 10 days was significantly higher in the PBPM group (47.1%) than that in the control group (34.4%, P<.005). The average time to reach the steady state was significantly (P<.005) shorter in the PBPM group compared to the control group (7.3 vs 8.6 days). WHAT IS NEW AND CONCLUSION: Warfarin therapy based on our novel PBPM was clinically safe and resulted in significantly better anticoagulation control compared to conventional care.


Assuntos
Anticoagulantes/administração & dosagem , Procedimentos Cirúrgicos Cardíacos/métodos , Serviço de Farmácia Hospitalar/organização & administração , Varfarina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anticoagulantes/efeitos adversos , Estudos de Coortes , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos/métodos , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Conduta do Tratamento Medicamentoso/organização & administração , Pessoa de Meia-Idade , Farmacêuticos/organização & administração , Tempo de Protrombina , Estudos Retrospectivos , Tromboembolia/prevenção & controle , Fatores de Tempo , Varfarina/efeitos adversos
4.
Phys Rev Lett ; 115(10): 102501, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382672

RESUMO

Differential cross sections of isoscalar and isovector spin-M1 (0(+)→1(+)) transitions are measured using high-energy-resolution proton inelastic scattering at E(p)=295 MeV on (24)Mg, (28)Si, (32)S, and (36)Ar at 0°-14°. The squared spin-M1 nuclear transition matrix elements are deduced from the measured differential cross sections by applying empirically determined unit cross sections based on the assumption of isospin symmetry. The ratios of the squared nuclear matrix elements accumulated up to E(x)=16 MeV compared to a shell-model prediction are 1.01(9) for isoscalar and 0.61(6) for isovector spin-M1 transitions, respectively. Thus, no quenching is observed for isoscalar spin-M1 transitions, while the matrix elements for isovector spin-M1 transitions are quenched by an amount comparable with the analogous Gamow-Teller transitions on those target nuclei.

5.
Dis Esophagus ; 27(3): 255-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23672461

RESUMO

Reconstruction following pharyngolaryngectomy with total esophagectomy is a challenging surgery to perform. Between April 2008 and August 2012, three types of modified gastric pull-up reconstruction procedures, including a gastric tube creation combined with a free jejunal transfer (n = 7), elongated gastric tube creation with vascular anastomoses (n = 2) and pedunculated gastric tube creation with Roux-en-Y anastomosis (n = 5), were performed after pharyngolaryngectomy with total esophagectomy. To clarify feasibility of these reconstructive methods, we retrospectively analyzed the short-term outcomes. There were no graft failures. Salivary fistulae were observed in two cases after high pharyngoenteral anastomoses due to oropharyngeal extension of hypopharyngeal cancers. Overall morbidity rate was 21.4%, and no deaths occurred. Although the operation time was shortest for pedunculated gastric tube reconstructions, morbidity rates were similar among all methods. All three types of modified gastric pull-up reconstruction procedures can be performed safely. We can choose one of these methods according to the tumor status and the patient condition, understanding advantages and disadvantages of each procedure.


Assuntos
Carcinoma/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagoplastia/métodos , Neoplasias Hipofaríngeas/cirurgia , Jejuno/transplante , Laringoplastia/métodos , Neoplasias Primárias Múltiplas/cirurgia , Faringe/cirurgia , Fístula das Glândulas Salivares/etiologia , Estômago/cirurgia , Idoso , Anastomose em-Y de Roux/efeitos adversos , Esofagectomia/efeitos adversos , Esofagoplastia/efeitos adversos , Sobrevivência de Enxerto , Humanos , Neoplasias Hipofaríngeas/complicações , Laringectomia/efeitos adversos , Laringoplastia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Faringectomia/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo
6.
Neuropathol Appl Neurobiol ; 39(4): 406-16, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22860700

RESUMO

AIMS: Increasing evidences suggest a similarity in the pathophysiological mechanisms of neuronal cell death in amyotrophic lateral sclerosis (ALS) and myofibre degeneration in sporadic inclusion body myositis (sIBM). The aim of this study is to elucidate the involvement of ALS-causing proteins in the pathophysiological mechanisms in sIBM. METHODS: Skeletal muscle biopsy specimens of five patients with sIBM, two with oculopharyngeal muscular dystrophy (OPMD), three with polymyositis (PM), three with dermatomyositis (DM), three with neurogenic muscular atrophy, and three healthy control subjects were examined. We analysed the expression and localization of familial ALS-causing proteins, including transactive response DNA binding protein-43 (TDP-43), fused in sarcoma/translocated in liposarcoma (FUS/TLS), Cu/Zn superoxide dismutase (SOD1) and optineurin (OPTN) by immunohistochemistry. RESULTS: TDP-43, OPTN and, to a lesser extent, FUS/TLS were more frequently accumulated in the cytoplasm in patients with sIBM and OPMD than in patients with PM, DM, neurogenic muscular atrophy, or healthy control subjects. SOD1 was accumulated in a small percentage of myofibres in patients with sIBM and OPMD, and to a very small extent in patients with PM and DM. Confocal microscopy imaging showed that TDP-43 proteins more often colocalized with OPTN than with FUS/TLS, p62 and phosphorylated Tau. CONCLUSIONS: These findings suggest that OPTN in cooperation with TDP-43 might be involved in the pathophysiological mechanisms of skeletal muscular degeneration in myopathy with rimmed vacuoles. Further investigation into these mechanisms is therefore warranted.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Miosite de Corpos de Inclusão/genética , Miosite de Corpos de Inclusão/patologia , Proteinopatias TDP-43/genética , Proteinopatias TDP-43/patologia , Fator de Transcrição TFIIIA/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Biópsia , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA/genética , Dermatomiosite/genética , Dermatomiosite/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana Transportadoras , Pessoa de Meia-Idade , Atrofia Muscular/genética , Atrofia Muscular/patologia , Distrofia Muscular Oculofaríngea/genética , Distrofia Muscular Oculofaríngea/patologia , Polimiosite/genética , Polimiosite/patologia , Proteína FUS de Ligação a RNA/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Fator de Transcrição TFIIIA/genética
8.
Phys Rev Lett ; 107(6): 062502, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902316

RESUMO

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

9.
J Viral Hepat ; 17(2): 123-9, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19674281

RESUMO

Combination therapy with adefovir dipivoxil (ADV) and lamivudine (LAM) is recommended for patients infected with LAM-refractory hepatitis B virus (HBV). However, the effects of such therapy on renal function and serum phosphorus levels have not been fully evaluated. Combination therapy with ADV and LAM was given to 37 patients infected with LAM-refractory HBV, including 17 with hepatic cirrhosis. Serum HBV DNA levels decreased to below 2.6 log(10) copies/mL in 23 (62%) of 37 patients at 12 months, 25 (78%) of 32 patients at 24 months, and 16 (84%) of 19 patients at 36 months. Except for one cirrhotic patient, serum alanine aminotransferase levels were below 50 IU/L in all patients during combination therapy. Serum creatinine levels increased in 14 (38%) of 37 patients, and serum phosphate levels decreased to below 2.5 mg/mL in 6 (16%) of 37 patients during combination therapy. Patients who received combination therapy for 36 months or longer had a significantly incidence of elevated serum creatinine levels. Fanconi syndrome occurred in a 57-year-old woman with cirrhosis after ADV was added to LAM. Combination therapy with ADV and LAM can maintain biochemical remission in patients with LAM-refractory HBV. However, the dosing interval of ADV should be adjusted according to renal function and serum phosphate levels in patients receiving long-term treatment.


Assuntos
Adenina/análogos & derivados , Antivirais/efeitos adversos , Farmacorresistência Viral , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Rim/efeitos dos fármacos , Organofosfonatos/efeitos adversos , Insuficiência Renal/induzido quimicamente , Adenina/efeitos adversos , Adenina/uso terapêutico , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/farmacologia , Antivirais/uso terapêutico , Creatinina/sangue , DNA Viral/sangue , Síndrome de Fanconi/induzido quimicamente , Feminino , Humanos , Lamivudina/farmacologia , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Organofosfonatos/uso terapêutico , Fosfatos/sangue , Soro/virologia , Resultado do Tratamento , Carga Viral
11.
Kyobu Geka ; 62(5): 354-7, 2009 May.
Artigo em Japonês | MEDLINE | ID: mdl-19425372

RESUMO

Occlusion of a coronary ostium due to fusion of the aortic cusp to the aortic wall is a rare but noteworthy anomaly, because it may cause a sudden death. We report a 9-year-old girl with severe stenosis of the left coronary ostium by the aortic cusp that fused to the aortic wall. The left coronary flow was restored by excision of the adherent left aortic cusp, and aortic valve replacement was performed with the technique of bilateral enlargement of the aortic valve ring (Yamaguchi's method) to prevent prosthesis-patient mismatch in the future. The patient had an uneventful recovery and was discharged 14th postoperative day (POD). Postoperative angiography showed no coronary ostial stenosis.


Assuntos
Valva Aórtica/anormalidades , Anomalias dos Vasos Coronários/patologia , Valva Aórtica/cirurgia , Criança , Anomalias dos Vasos Coronários/cirurgia , Feminino , Humanos
12.
Kyobu Geka ; 62(12): 1061-4, 2009 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-19894571

RESUMO

A 6-year-old boy was diagnosed with aggravation of diffuse supravalvular aortic stenosis (SVAS). The pressure gradient between the sinus of Valsalva and ascending aorta was 48 mmHg. The diameter of the sino-tubular junction was 7 mm and the ascending aorta was hypoplastic. We performed Myers operation because 3 sinus reconstructions had resulted in superior hemodynamics and reductions in both mortality rate and need for reoperation. We avoided using autologous pericardium because of the possibility of shrinkage and aneurysm. We could easily perform patch enlargement of the ascending aorta by selective cerebral perfusion. The postoperative course was excellent and there was no SVAS or aortic regurgitation (AR). A catheterization showed the pressure gradient was 5 mmHg with trivial AR upon follow-up at 1 year.


Assuntos
Aorta/anormalidades , Estenose Aórtica Supravalvular/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Estenose Aórtica Supravalvular/congênito , Criança , Humanos , Masculino
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(4 Pt 1): 042902, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18517676

RESUMO

We study a two-dimensional reaction-diffusion equation for calcium oscillation with a pacemaker region. When the pacemaker entrains the whole system, circular waves are observed as a target pattern. However, if the pace of the pacemaker is too fast, the pulse propagation to the outer region sometimes fails in a chaotic manner. We find that spiral waves are spontaneously created at the interface between the pacemaker region and the outer region.


Assuntos
Relógios Biológicos/fisiologia , Cálcio/fisiologia , Modelos Biológicos , Simulação por Computador , Difusão , Oscilometria/métodos
14.
Kyobu Geka ; 61(12): 1019-22, 2008 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-19048899

RESUMO

A 53-year-old woman with a double, double, double (DDD) pacemaker due to complete atrioventricular block was admitted to our hospital with a diagnosis of congestive heart failure. At the time of admission, she was in a hypoxic state with cyanosis and clubbed finger. The ultrasonic cardiogram showed a severe degree of tricuspid valve regurgitation and a thin left ventricular septal wall. Transesophageal echocardiography revealed a patent foramen ovale (PFO) with continuous right to left shunt flow. She was diagnosed with cardiac sarcoidosis with hypoxemia caused by PFO. PFO closure and tricuspid valve annuloplasty (DeVega method) were performed. Following surgery, the patient's hypoxemia improved and the cyanosis disappeared. The patient was discharged 37 days after the operation.


Assuntos
Cardiomiopatias/diagnóstico , Forame Oval Patente/diagnóstico , Hipóxia/diagnóstico , Feminino , Forame Oval Patente/complicações , Forame Oval Patente/cirurgia , Humanos , Hipóxia/etiologia , Pessoa de Meia-Idade , Sarcoidose/diagnóstico
15.
Nat Commun ; 9(1): 1594, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29686394

RESUMO

The nuclear shell structure, which originates in the nearly independent motion of nucleons in an average potential, provides an important guide for our understanding of nuclear structure and the underlying nuclear forces. Its most remarkable fingerprint is the existence of the so-called magic numbers of protons and neutrons associated with extra stability. Although the introduction of a phenomenological spin-orbit (SO) coupling force in 1949 helped in explaining the magic numbers, its origins are still open questions. Here, we present experimental evidence for the smallest SO-originated magic number (subshell closure) at the proton number six in 13-20C obtained from systematic analysis of point-proton distribution radii, electromagnetic transition rates and atomic masses of light nuclei. Performing ab initio calculations on 14,15C, we show that the observed proton distribution radii and subshell closure can be explained by the state-of-the-art nuclear theory with chiral nucleon-nucleon and three-nucleon forces, which are rooted in the quantum chromodynamics.

16.
Br J Ophthalmol ; 91(2): 161-5, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16914470

RESUMO

AIM: To assess the efficacy and safety of an intravitreal injection of bevacizumab (Avastin(R)) for myopic choroidal neovascularisation (mCNV). METHODS: Intravitreal bevacizumab (1 mg) was injected into eight eyes of eight patients with mCNV in this non-randomised, interventional case series. The best-corrected visual acuity (BCVA) was measured and the optical coherence tomography (OCT) and fluorescein angiography findings were examined before and after treatment. The minimum follow-up time was 3 months. RESULTS: The mean BCVA was 0.26 before treatment and 0.51 at the last visit (p = 0.009). The BCVA improved to two or more lines in six eyes (75%) and remained the same in two eyes (25%). Leakage from the mCNV on fluorescein angiography decreased in seven eyes (87.5%). The choroidal neovascularisation area on fluorescein angiography (p = 0.049) and the foveal thickness on OCT images decreased significantly (p = 0.027) after the treatment. No major complications developed. CONCLUSION: Intravitreal injection of bevacizumab seems to be an effective and safe treatment for mCNV.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Neovascularização de Coroide/tratamento farmacológico , Miopia Degenerativa/complicações , Adulto , Idoso , Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Bevacizumab , Neovascularização de Coroide/etiologia , Neovascularização de Coroide/patologia , Neovascularização de Coroide/fisiopatologia , Feminino , Seguimentos , Fóvea Central/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/efeitos dos fármacos
17.
Leukemia ; 31(12): 2815-2823, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28555081

RESUMO

The biology, clinical phenotype and progression rate of chronic myelomonocytic leukemia (CMML) are highly variable due to diverse initiating and secondary clonal genetic events. To determine the effects of molecular features including clonal hierarchy in CMML, we studied whole-exome and targeted next-generation sequencing data from 150 patients with robust clinical and molecular annotation assessed cross-sectionally and at serial time points of disease evolution. To identify molecular lesions unique to CMML, we compared it to the related myeloid neoplasms (N=586), including juvenile myelomonocytic leukemia, myelodysplastic syndromes (MDS) and primary monocytic acute myeloid leukemia and discerned distinct molecular profiles despite similar pathomorphological features. Within CMML, mutations in certain pathways correlated with clinical classification, for example, proliferative vs dysplastic features. While most CMML patients (59%) had ancestral (dominant/co-dominant) mutations involving TET2, SRSF2 or ASXL1 genes, secondary subclonal hierarchy correlated with clinical phenotypes or outcomes. For example, progression was associated with acquisition of new expanding clones carrying biallelic TET2 mutations or RAS family, or spliceosomal gene mutations. In contrast, dysplastic features correlated with mutations usually encountered in MDS (for example, SF3B1 and U2AF1). Classification of CMML based on hierarchies of ancestral and subclonal mutational events may correlate strongly with clinical features and prognosis.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genômica , Leucemia Mielomonocítica Crônica/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Aberrações Cromossômicas , Evolução Clonal , Hibridização Genômica Comparativa , Estudos Transversais , Feminino , Frequência do Gene , Genômica/métodos , Humanos , Cariótipo , Leucemia Mielomonocítica Crônica/diagnóstico , Leucemia Mielomonocítica Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Prognóstico , Sequenciamento do Exoma
18.
Int J Immunopathol Pharmacol ; 19(2): 357-68, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16831302

RESUMO

The quality and quantity of CD4+25+ regulatory T cells (Treg) in silicosis patients (SIL) were examined and compared with results from healthy donors (HD) because SIL often develop autoimmune diseases along with pulmonary disorders. Peripheral blood mononuclear cells from 57 SIL and 50 HD were analyzed for Treg. Treg frequency and clinical parameters were subjected to a factor analysis. Treg and CD4+25- T cells (Tneg) from five HD and five SIL, sorted by flow-cytometer, were used for functional assays of Treg, the expression pattern of Treg specific genes (FoxP3, GITR and CTLA-4) and activation-related genes (CD122 and CD123). Although the actual frequency of Treg did not differ between SIL and HD, the age-corrected level was reduced in SIL. The factor analysis showed that Treg frequency was positively associated with the serum level of IL-2. The inhibitory effect of Treg on Tneg activation was decreased when the Treg:Tneg ratio was 1:1/4 to 1/2. In addition, Treg dominancy of FoxP3 and CTLA-4 expression and Tneg dominancy of CD132 expression found in HD were lost in SIL. These results indicated that the Treg fraction in SIL may be substituted with chronically activated T cells due to recurrent exposure to silica, resulting in a reduction in the frequency and function of Treg. Since the reduction of Treg may precede the clinical manifestation, as silicosis may be a pre-clinical status for autoimmune diseases, control of Treg function using cell and/or gene therapy may be a good way to manage autoimmune disease.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Receptores de Interleucina-2/imunologia , Silicose/imunologia , Linfócitos T Reguladores/imunologia , Idoso , Anticorpos Antinucleares/análise , Apoptose/imunologia , Doenças Autoimunes/etiologia , Doenças Autoimunes/imunologia , DNA Complementar/biossíntese , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática , Análise Fatorial , Feminino , Expressão Gênica/fisiologia , Humanos , Interleucina-2/imunologia , Masculino , Transdução de Sinais/fisiologia , Silicose/genética , Receptor fas/imunologia
19.
Toxicol In Vitro ; 20(5): 767-73, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16311011

RESUMO

The aim of this study is to optimize the experimental conditions for an in vitro skin sensitization test using the human cell lines THP-1 and U-937. As regards pre-culturing time, the expression of CD86 on DNCB-treated THP-1 cells tended to be higher after 48h and 72h pre-culture compared with other time points evaluated. Next, we investigated the effect of chemical treatment time, and found that induction of CD86 expression on THP-1 cells by DNCB reached a plateau after 24h. Augmentation of CD86 expression is often observed when cells are treated with a subtoxic dose of allergens. To determine the appropriate dose of test samples, the cytotoxicity of test samples to THP-1 and U-937 cells was assessed with MTT assay, and the 50% inhibitory concentration (IC50) of each test sample was calculated. Based on the cytotoxicity assay data, four concentrations in the range between toxic and non-toxic were selected (0.1x, 0.5x, 1x and 2x IC50). Several kinds of antibodies were tested for staining THP-1 and U-937 cells treated with allergens/non-allergens (e.g., DNCB, Ni/SLS), and suitable antibodies for staining CD86 and CD54 were selected. We confirmed that the working dilutions of the selected CD86 and CD54 antibodies were appropriate for use in our method. The effect of an FcR blocking procedure was also evaluated. The mean fluorescence intensity (MFI value) was decreased by the FcR blocking procedure, which indicated that non-specific staining was blocked. Therefore, this procedure should be included in the method. Based on our findings, the protocol for this assay was optimized and the experimental conditions to be used in a future validation study were identified. We propose to call this kind of in vitro skin sensitization test h-CLAT, which is short for human Cell Line Activation Test.


Assuntos
Alérgenos/toxicidade , Pele/efeitos dos fármacos , Antígenos de Superfície/análise , Antígeno B7-2/análise , Linhagem Celular , Dinitroclorobenzeno/toxicidade , Humanos , Molécula 1 de Adesão Intercelular/análise , Receptores Fc/fisiologia , Pele/imunologia , Testes Cutâneos , Fatores de Tempo
20.
Toxicol In Vitro ; 20(5): 774-84, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16337770

RESUMO

Recent regulatory changes have placed a major emphasis on in vitro safety testing and alternative models. In regard to skin sensitization tests, dendritic cells (DCs) derived from human peripheral blood have been considered in the development of new in vitro alternatives. Human cell lines have been also reported recently. In our previous study, we suggested that measuring CD86 and/or CD54 expression on THP-1 cells (human monocytic leukemia cell line) could be used as an in vitro skin sensitization method. An inter-laboratory study among two laboratories was undertaken in Japan in order to further develop an in vitro skin sensitization model. In the present study, we used two human cell lines: THP-1 and U-937 (human histiocytic lymphoma cell line). First we optimized our test protocol (refer to the related paper entitled "optimization of the h-CLAT protocol" within this journal) and then we did an inter-laboratory validation with nine chemicals using the optimized protocol. We measured the expression of CD86 and CD54 on the above cells using flow cytometry after a 24h and 48h exposure to six known allergens (e.g., DNCB, pPD, NiSO(4)) and three non-allergens (e.g., SLS, tween 80). For the sample test concentration, four doses (0.1x, 0.5x, 1x, and 2x of the 50% inhibitory concentration (IC(50))) were evaluated. IC(50) was calculated using MTT assay. We found that allergens/non-allergens were better predicted using THP-1 cells compared to U-937 cells following a 24 h and a 48 h exposure. We also found that the 24h treatment time tended to have a better accuracy than the 48 h treatment time for THP-1 cells. Expression of CD86 and CD54 were good predictive markers for THP-1 cells, but for U-937 cells, expression of CD86 was a better predictor than CD54, at the 24h and the 48 h treatment time. The accuracy also improved when both markers (CD86 and CD54) were used as compared with a single marker for THP-1 cells. Both laboratories gave a good prediction of allergen/non-allergen, especially using THP-1 cells. These results suggest that our method, human Cell Line Activation Test (h-CLAT), using human cell lines THP-1 and U-937, but especially THP-1 cells at 24h treatment, may be a useful in vitro skin sensitization model to predict various contact allergens.


Assuntos
Alérgenos/toxicidade , Pele/efeitos dos fármacos , Antígeno B7-2/análise , Antígenos CD4/análise , Linhagem Celular , Sobrevivência Celular , Humanos , Laboratórios , Fenótipo , Pele/imunologia , Testes Cutâneos , Fatores de Tempo , Células U937
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