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1.
J Endocrinol Invest ; 41(12): 1409-1416, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29931474

RESUMO

PURPOSE: Our insight in the genetics of Hashimoto's thyroiditis (HT) has become clearer through information provided by genome-wide association studies and candidate gene studies, but remains still not fully understood. Our aim was to assess how many different genetic risk variants contribute to the development of HT. METHODS: 147 HT cases (10.2% men) and 147 controls (13.6% men) were qualified for the analysis. Intrinsic and environmental factors were controlled for. Polymorphisms (SNP) were chosen based on the literature and included markers of the genes PTPN22, CTLA4, TG, TPO among others, and of genomic regions pointed by GWAS studies. SNP were typed on a microarray. Variants in the HLA-DRB1 gene were identified by Sanger sequencing. RESULTS: Multivariate predisposition to HT was modeled. Based on the investigated group, a model of seven variables was obtained. The variability explained by this model was assessed at only 5.4821% (p = 2 × 10-6), which indicates that many dozens of factors are required simultaneously to explain HT predisposition. CONCLUSIONS: We analyzed genetic regions commonly and most significantly associated with autoimmune thyroid disorders in the literature, on a carefully selected cohort. Our results indicated a lack of possibility to predict the risk of HT development, even with a multivariate model. We therefore conclude that strong associations of single genetic regions with HT should be interpreted with great caution. We believe that a change in the attitude towards genetic association analyses of HT predisposition is necessary. Studies including multiple factors simultaneously are needed to unravel the intricacies of genetic associations with HT.


Assuntos
Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Cadeias HLA-DRB1/genética , Doença de Hashimoto/sangue , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Hipotireoidismo/genética , Masculino
2.
Phys Rev Lett ; 110(22): 222002, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23767713

RESUMO

We report the results of a high-statistics search for H dibaryon production in inclusive Υ(1S) and Υ(2S) decays. No indication of an H dibaryon with a mass near the M(H)=2m(Λ) threshold is seen in either the H→Λpπ(-) or ΛΛ decay channels and 90% confidence level branching-fraction upper limits are set that are between one and two orders of magnitude below the measured branching fractions for inclusive Υ(1S) and Υ(2S) decays to antideuterons. Since Υ(1S,2S) decays produce flavor-SU(3)-symmetric final states, these results put stringent constraints on H dibaryon properties. The results are based on analyses of 102 million Υ(1S) and 158 million Υ(2S) events collected with the Belle detector at the KEKB e(+)e(-) collider.

3.
Phys Rev Lett ; 108(17): 171801, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22680851

RESUMO

We report a measurement of the CP-violation parameter sin2φ1 at the Υ(5S) resonance using a new tagging method, called "B-π tagging." In Υ(5S) decays containing a neutral B meson, a charged B, and a charged pion, the neutral B is reconstructed in the J/ψK(S)(0) CP-eigenstate decay channel. The initial flavor of the neutral B meson at the moment of the Υ(5S) decay is opposite to that of the charged B and may thus be inferred from the charge of the pion without reconstructing the charged B. From the asymmetry between B-π(+) and B-π(-) tagged J/ψK(S)(0) yields, we determine sin2φ1=0.57±0.58(stat)±0.06(syst). The results are based on 121 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider.

4.
Phys Rev Lett ; 105(19): 191803, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21231162

RESUMO

We report a first measurement of inclusive B→Xsη decays, where Xs is a charmless state with unit strangeness. The measurement is based on a pseudoinclusive reconstruction technique and uses a sample of 657×10(6)BB pairs accumulated with the Belle detector at the KEKB e+e- collider. For MXs < 2.6 GeV/c2, we measure a branching fraction of [26.1±3.0(stat)-2.1+1.9(syst)-7.1+4.0(model)]×10(-5) and a direct CP asymmetry of ACP=-0.13±0.04-0.03+0.02. Over half of the signal occurs in the range MXs > 1.8 GeV/c2.

5.
Phys Rev Lett ; 104(18): 181602, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20482167

RESUMO

We have searched for CP violation in the charmed meson decays D((s))(+) --> K(S)(0)pi(+) and D((s))(+) --> K(S)(0)K(+) using 673 fb(-1) of data collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. No evidence for CP violation is observed. We report the most sensitive CP asymmetry measurements to date for these decays: A(CP)(D(+)-->K(S)(0)pi(+)) = (-0.71 +/- 0.19 +/- 0.20)%, A(CP)(D(s)(+) --> K(S)(0)pi(+)) = (+5.45 +/- 2.50 +/- 0.33)%, A(CP)(D(+) --> K(S)(0)K(+)) = (-0.16 +/- 0.58 +/- 0.25)%, and A(CP)(D(s)(+) --> K(S)(0)K(+)) = (+0.12 +/- 0.36 +/- 0.22)%, where the first uncertainties are statistical and the second are systematic.

6.
Phys Rev Lett ; 104(23): 231801, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20867227

RESUMO

First observations of the B(s)(0) → D(s)(*-) π+, B(s)(0) → D(s)(-) ρ+ and B(s)(0) → D(s)(*-) ρ+ decays are reported together with measurements of their branching fractions: B(B(s)(0) → D(s)(*-) π+) = [2.4(-0.4)(+0.5)(stat) ± 0.3(syst) ± 0.4(f(s))]×10(-3), B(B(s)(0) → D(s)(-) ρ+) = [8.5(-1.2)(+1.3)(stat) ± 1.1(syst) ± 1.3(f(s))]×10(-3) and B(B(s)(0) → D(s)(*-) ρ+) = [11.9(-2.0)(+2.2)(stat) ± 1.7(syst) ± 1.8(f(s))]×10(-3) (f(s) = N(B(s)(*) B(s)(*))/N(bb)). From helicity-angle distributions, we measured the longitudinal polarization fraction in B(s)(0) → D(s)(*-) ρ+ decays to be f(L)(B(s)(0) → D(s)(*-) ρ+) = 1.05(-0.10)(+0.08)(stat)(-0.04)(+0.03)(syst). These results are based on a 23.6 fb(-1) data sample collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider.


Assuntos
Partículas Elementares , Teoria Quântica
7.
Phys Rev Lett ; 105(9): 091801, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20868151

RESUMO

We search for dimuon decays of a low mass particle in the decays B0→K*0 X and B0→ρ0 X using a data sample of 657×10(6)BB events collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We find no evidence for such a particle in the mass range from 212 MeV/c2 to 300 MeV/c2 for lifetimes below 10(-12) s, and set upper limits on its branching fractions. In particular, we search for a particle with a mass of 214.3 MeV/c2 reported by the HyperCP experiment, and obtain upper limits on the products B(B0→K*0 X)×B(X→µ+ µ- )<2.26(2.27)×10(-8) and B(B0→ρ0 X)×B(X→µ+ µ-)<1.73(1.73)×10(-8) at 90% C.L. for a scalar (vector) X particle.


Assuntos
Modelos Químicos , Nanopartículas/química , Física Nuclear , Algoritmos , Transferência de Energia , Íons , Aceleradores de Partículas
8.
Phys Rev Lett ; 103(17): 171801, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-19905747

RESUMO

We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.

9.
Endocr Connect ; 8(11): 1474-1482, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31634866

RESUMO

OBJECTIVE: Negative pressure wound therapy (NPWT) has been used to treat diabetic foot ulcerations (DFUs). Its action on the molecular level, however, is only partially understood. Some earlier data suggested NPWT may be mediated through modification of local gene expression. As methylation is a key epigenetic regulatory mechanism of gene expression, we assessed the effect of NPWT on its profile in patients with type 2 diabetes (T2DM) and neuropathic non-infected DFUs. METHODS: Of 36 included patients, 23 were assigned to NPWT and 13 to standard therapy. Due to ethical concerns, the assignment was non-randomized and based on wound characteristics. Tissue samples were obtained before and 8 ± 1 days after therapy initiation. DNA methylation patterns were checked by Illumina Methylation EPIC kit. RESULTS: In terms of clinical characteristics, the groups presented typical features of T2DM; however, the NPWT group had significantly greater wound area: 16.8 cm2 vs 1.4 cm2 (P = 0.0003). Initially only one region at chromosome 5 was differentially methylated. After treatment, 57 differentially methylated genes were found, mainly located on chromosomes 6 (chr6p21) and 20 (chr20p13); they were associated with DNA repair and autocrine signaling via retinoic acid receptor. We performed differential analyses pre treatment and post treatment. The analysis revealed 426 differentially methylated regions in the NPWT group, but none in the control group. The enrichment analysis showed 11 processes significantly associated with NPWT, of which 4 were linked with complement system activation. All but one were hypermethylated after NPWT. CONCLUSION: The NPWT effect on DFUs may be mediated through epigenetic changes resulting in the inhibition of complement system activation.

10.
Acta Biochim Pol ; 40(4): 471-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8140820

RESUMO

In vitro addition of 16,16'-dimethyl prostaglandin E2 to Golgi-rich membrane fraction in final concentration of 0.1 microgram/1 mg of protein increased generally the activity of galactosyltransferase in comparison with control. The percentage of phospholipids in the whole fraction was similar in both investigated groups, only the sum of phosphatidylethanolamine+phosphatidic acid was significantly lower after addition of dmPGE2 than in the control (0.001 < P < 0.01).


Assuntos
16,16-Dimetilprostaglandina E2/farmacologia , Galactosiltransferases/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Animais , Feminino , Complexo de Golgi/enzimologia , Complexo de Golgi/metabolismo , Técnicas In Vitro , Fígado/metabolismo , N-Acetil-Lactosamina Sintase/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Wistar
11.
J Physiol Pharmacol ; 44(4): 383-90, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8123885

RESUMO

Addition in vitro of ethanol solution of PGE1 to isolated Golgi-rich membrane fraction caused great alterations in galactosyltransferase activity, marker enzyme of these membranes. Ethanol as a solvent of PGE1 has an influence on the activity of the enzyme as well as the membrane permeability, different drugs penetration and availability of substrates. Then, additional control with ethanol in identical concentration as in the investigated sample was performed. In a dose 1 microgram PGE1 per 1 mg of protein (and lower concentration of ethanol c. 0.09%) the stimulation of this enzyme activity (excluding 2 and 6 hours s after Golgi membrane isolation) was above 30% in comparison with the control.


Assuntos
Alprostadil/farmacologia , Etanol/farmacologia , Complexo de Golgi/enzimologia , Fígado/enzimologia , N-Acetil-Lactosamina Sintase/metabolismo , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Feminino , Complexo de Golgi/efeitos dos fármacos , Técnicas In Vitro , Metabolismo dos Lipídeos , Fosfolipídeos/metabolismo , Proteínas/metabolismo , Ratos , Ratos Wistar , Solventes
12.
J Photochem Photobiol B ; 57(1): 51-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11100837

RESUMO

The present paper describes synthesis and spectroscopic properties of novel cationic meso-tetraphenylporphyrins bearing two (trans) (P2) or three (P3) triphenylphosphonium substituents. The porphyrin aggregation in aqueous solutions is discussed in detail. Porphyrin binding to and self-organization onto long-range assemblies on poly(dA-dT)2 or poly(dG-dC)2 were probed by combination of absorption, fluorescence, circular dichroism (CD), transient and resonance light-scattering (RLS) techniques. The higher hydrophobicity of P2 is manifested by more extensive self-organization. Induced CD and intensive RLS indicate binding to the chiral environment on the nucleic acids exterior and exciton coupling between adjacent porphyrin moieties. The CD spectra of P2 on poly(dG-dC), and poly(dA-dT)2 suggest that the binding geometry is essentially independent of the base sequence. The fluorescence lifetime of about 4 ns was attributed to the long-range assembly. In the case of P3 the distinctly different CD spectra induced by GC or AT base-pair regions reveal that the number of the substituents determines how closely the porphyrin can approach the specific electronic environment on the nucleic acid exterior. The fluorescence lifetime of the P3 assembly is about 2 ns.


Assuntos
Compostos Organofosforados/química , Poli dA-dT/química , Polidesoxirribonucleotídeos/química , Porfirinas/química , Dicroísmo Circular , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Conformação de Ácido Nucleico , Compostos Organofosforados/síntese química , Porfirinas/síntese química , Espectrofotometria , Relação Estrutura-Atividade
13.
Arch Mal Coeur Vaiss ; 85(7): 987-92, 1992 Jul.
Artigo em Francês | MEDLINE | ID: mdl-1449346

RESUMO

This study analysed the possibilities of returning to work of professional drivers after a cardiac event and rehabilitation. The population comprised 94 consecutive patients, all men, average age 48.8 years (range 30 to 63 years) referred after coronary bypass surgery (N = 39), myocardial infarction (N = 38), angina (N = 4) or valve replacement surgery (N = 13). Advice on professional reinsertion was given after the rehabilitation program, authorization to drive being given in the absence of cardiac symptoms, residual myocardial ischaemia, severe left ventricular dysfunction and serious ventricular arrhythmias. After 35 months, 4 patients were lost to follow-up; of the 90 remaining patients, the frequency of return to work (maximal at the 9th month) was 65.6% with 84.7% obtaining a renewal of their driving licence. In this series, 81% of patients were asymptomatic, 2 died, 16.7% had further cardiovascular complications. The morbidity and mortality were significantly greater in the group who had to stop driving (N = 40) (32.5% vs 8%, p < 0.001). Non complications occurred during work in those who resumed driving. This study confirms the safety of allowing low risk professional drivers, identified during cardiac rehabilitation by simple, reliable clinical and paraclinical criteria, to return to work.


Assuntos
Condução de Veículo , Doença das Coronárias/reabilitação , Doenças das Valvas Cardíacas/reabilitação , Infarto do Miocárdio/reabilitação , Adulto , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Função Ventricular Esquerda , Trabalho
14.
Arch Mal Coeur Vaiss ; 79(10): 1506-14, 1986 Sep.
Artigo em Francês | MEDLINE | ID: mdl-3099684

RESUMO

Propafenone, an antiarrhythmic drug of IC type, was applied to 10 patients with supraventricular tachycardia (SVT) produced by intranodal reentry (group I) and in 14 patients with reentry by an accessory atrioventricular (AV) pathway (group II), 10 of them suffering from orthodromic SVT. Propafenone given intravenously depresses or blocks the antegrade or retrograde conduction in the AV node and in the accessory AV pathway. The same effect is observed with orally given propafenone: 66% of antegrade blocking and 54% of retrograde blocking of the accessory conduction pathway. Intravenously given propafenone reduces within 2 to 3 min by antegrade or retrograde blocking 70% of SVT produced by intranodal reentry and by 85% of SVT produced by reentry by the accessory pathway. After injection it becomes impossible to induce intranodal SVT in 60% of cases and SVT by the accessory pathway reentry in 28% of cases. With oral treatment (600 mg/day) reinduction of intranodal SVT becomes impossible in 66% of cases and of SVT produced by reentry by the accessory pathway in 42% of cases. Long-term oral administration (17 +/- 3.7 months) of the same dose prevents 88% of SVT produced by internodal reentry and 80% of spontaneous SVT produced by reentry by the accessory pathway. Cardiologic tolerance is satisfactory: one case of atrioventricular and intraventricular dysrhythmia is observed. The same holds true for general tolerance: in 2 cases drug administration is discontinued and 11 patients present neurologic and digestive troubles improving after lowering the dosage or increasing the fractionation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Propafenona/administração & dosagem , Taquicardia por Reentrada no Nó Atrioventricular/tratamento farmacológico , Taquicardia Supraventricular/tratamento farmacológico , Síndrome de Wolff-Parkinson-White/tratamento farmacológico , Administração Oral , Adulto , Idoso , Eletrocardiografia , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Síndrome de Wolff-Parkinson-White/fisiopatologia
15.
Arch Mal Coeur Vaiss ; 79(9): 1361-6, 1986 Aug.
Artigo em Francês | MEDLINE | ID: mdl-3101641

RESUMO

Lyme's disease due to Borrelia Burgdorferii is a rare cause of acute atrioventricular block (AVB) which is the commonest cardiac complication. Cutaneous, neurological and articular involvement complete the clinical picture of this condition. These two cases, confirmed by serology, support previously reported data describing the favourable prognosis of these conduction defects (suprahisian and/or hisian in our 2 cases) which regress completely, irrespective of their degree of severity. The authors also describe AVB occurring without extracardiac manifestations of this condition and a documented case of sinoatrial block, indicating a new zone of infestation.


Assuntos
Bloqueio Cardíaco/etiologia , Doença de Lyme/complicações , Eletrocardiografia , Bloqueio Cardíaco/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Sinoatrial/diagnóstico , Bloqueio Sinoatrial/etiologia
16.
J Plant Physiol ; 168(11): 1191-9, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21492955

RESUMO

Violets of the sections Melanium were examined for their colonization by arbuscular mycorrhizal fungi (AMF). Heartsease (Viola tricolor) from several heavy metal soils was AMF-positive at many sites but not at extreme biomes. The zinc violets Viola lutea ssp. westfalica (blue zinc violet) and ssp. calaminaria (yellow zinc violet) were always AMF-positive on heavy metal soils as their natural habitats. As shown for the blue form, zinc violets germinate independently of AMF and can be grown in non-polluted garden soils. Thus the zinc violets are obligatorily neither mycotrophs nor metalophytes. The alpine V. lutea, likely ancestor of the zinc violets, was at best poorly colonized by AMF. As determined by atomic absorption spectrometry, the contents of Zn and Pb were lower in AMF colonized plants than in the heavy metal soils from where the samples had been taken. AMF might prevent the uptake of toxic levels of heavy metals into the plant organs. Dithizone staining indicated a differential deposition of heavy metals in tissues of heartsease. Leaf hairs were particularly rich in heavy metals, indicating that part of the excess of heavy metals is sequestered into these cells.


Assuntos
Metais Pesados/metabolismo , Micorrizas/crescimento & desenvolvimento , Folhas de Planta/química , Raízes de Plantas/química , Viola/microbiologia , Análise de Variância , Ditizona/metabolismo , Germinação , Metais Pesados/análise , Raízes de Plantas/microbiologia , Caules de Planta/química , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Espectrofotometria Atômica , Viola/química , Viola/crescimento & desenvolvimento
18.
Phys Rev Lett ; 102(22): 221802, 2009 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-19658854

RESUMO

We report the first observation of the doubly Cabibbo-suppressed decay D_{s};{+}-->K;{+}K;{+}pi;{-} using 605 fb;{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e;{+}e;{-} collider. The branching ratio with respect to its Cabibbo-favored counterpart B(D_{s};{+}-->K;{+}K;{+}pi;{-})/B(D_{s};{+}-->K;{+}K;{-}pi;{+}) is (0.229+/-0.028+/-0.012)%, where the first uncertainty is statistical and the second is systematic. We also report a significantly improved measurement of the doubly Cabibbo-suppressed decay D;{+}-->K;{+}pi;{+}pi;{-}, with a branching ratio B(D;{+}-->K;{+}pi;{+}pi;{-})/B(D;{+}-->K;{-}pi;{+}pi;{+})=(0.569+/-0.018+/-0.014)%.

19.
Phys Rev Lett ; 100(24): 241801, 2008 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-18643570

RESUMO

We present a measurement of the branching fraction B(D{s}{+}-->mu{+}nu{mu}) using a 548 fb{-1} data sample collected by the Belle experiment at the KEKB e{+}e{-} collider. The D{s} momentum is determined by reconstruction of the system recoiling against DKgammaX in events of the type e{+}e{-}-->D{s}{*}DKX, D{s}{*}-->D{s}gamma, where X represents additional pions or photons from fragmentation. This full-reconstruction method provides high resolution in the neutrino momentum and thus good background separation, equivalent to that achieved by experiments at the tau-charm factories. We obtain the branching fraction B(D{s}{+}-->mu{+}nu{mu})=[6.44+/-0.76(stat)+/-0.57(syst)]x10{-3}, implying a D{s} decay constant of f{D{s}}=[275+/-16(stat)+/-12(syst)] MeV.

20.
Phys Rev Lett ; 100(12): 121801, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18517854

RESUMO

We search for the radiative penguin decays B_{s}{0}-->varphigamma and B_{s}{0}-->gammagamma in a 23.6 fb{-1} data sample collected at the Upsilon(5S) resonance with the Belle detector at the KEKB e{+}e{-} asymmetric-energy collider. We observe for the first time a radiative penguin decay of the B_{s}{0} meson in the B_{s}{0}-->varphigamma mode and we measure B(B_{s}{0}-->varphigamma)=(57_{-15}{+18}(stat)-11+12(syst))x10{-6}. No significant B_{s}{0}-->gammagamma signal is observed and we set a 90% confidence level upper limit of B(B_{s}{0}-->gammagamma)<8.7x10{-6}.

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