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1.
Metab Brain Dis ; 30(5): 1295-308, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26141074

RESUMO

The aim of this study was to evaluate the structural integrity of the thalamic connectivity of specific fiber tracts in different stages of Alzheimer's disease (AD) using diffusion tensor imaging (DTI). Thirty-five patients with AD and 22 normal control (NC) subjects were recruited. Based on Mini Mental State Examination score, the AD patients were divided into three subgroups for comparison with the NC group: mild (mi-AD, n = 14), moderate (mo-AD, n = 12), and severe (se-AD, n = 9) AD. The fornix (FX), anterior thalamic radiation (ATR), and posterior thalamic radiation (PTR) were selected to represent the thalamic connectivity with other brain regions. The fornix was divided into the column and body of the fornix (FX-1) and the bilateral fornix (crus)/stria terminalis (FX-2/ST) based on the atlas. Through the atlas-based analysis and fiber tracking method, we measured fractional anisotropy (FA), mean diffusivity (MD), and tract volume to reflect the microstructural and macrostructural changes of these fibers during AD progression. There were significant differences in the FA and MD of all fibers, except the right PTR, between the AD and NC subjects. Further subgroup analyses revealed that the mi-AD subgroup had decreased FA only in the FX-1 and increased MD in the FX-1 and bilateral ATR, the mo-AD subgroup showed declined FA and increased MD in the FX-1, bilateral FX-2/ST and ATR; the se-AD subgroup exhibited lower FA and higher MD values in all fibers except the right PTR. We also found reduced tract volume values in the FX and left ATR in the AD patients. Further subgroup analyses revealed that these differences only existed in the se-AD patients. Our DTI analyses indicate that the integrity of thalamic connectivity is progressively disrupted following cognitive decline in AD and that DTI parameters in the column and body of the fornix show promise as potential markers for the early diagnosis of AD and for monitoring disease progression.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Imagem de Tensor de Difusão , Rede Nervosa/metabolismo , Rede Nervosa/patologia , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Chemphyschem ; 11(3): 696-705, 2010 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-20041456

RESUMO

Radical-molecule complexes associated with the hydroperoxyl radical (HOO) play an important role in atmospheric chemistry. Herein, the nature of the coupling interactions between sulfurous acid (H(2)SO(3)) and the HOO radical is systematically investigated at the B3LYP/6-311++G(3df,3pd) level of theory in combination with the atoms in molecules (AIM) theory, the natural bond orbital (NBO) method, and energy decomposition analyses (EDA). Eight stable stationary points possessing double H-bonding features were located on the H(2)SO(3)...HOO potential energy surface. The largest binding energies of -12.27 and -11.72 kcal mol(-1) are observed for the two most stable complexes, where both of them possess strong double intermolecular H-bonds of partially covalence. Moreover, the characteristics of the IR spectra for the two most stable complexes are discussed to provide some help for their possible experimental identification.


Assuntos
Peróxido de Hidrogênio/química , Ácidos de Enxofre/química , Ligação de Hidrogênio , Modelos Químicos , Modelos Moleculares
3.
Kaohsiung J Med Sci ; 35(5): 257-264, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30897293

RESUMO

To evaluate the Efficacy and safety of phosphodiesterase type 5 inhibitors as a medical therapy for distal ureteral calculi by means of a systematic review and network meta-analysis (NMA). We searched the Embase, Medline, and the Cochrane Central Register of Controlled Trials for randomised controlled trials (RCTs) published before May, 2017. Stone passage rate as the primary outcome. We used random effects model for pairwise meta-analyses and Bayesian random effects model for NMA. We evaluated the quality of evidence by the GRADE framework for each network estimate. Five RCTs (861 patients) comparing four different interventions. The results of NMA showed that compared with tamsulosin alone, tamsulosin combined with tadalafil group was associated with significantly higher stone passage rate (odds radio [OR] 2.55, 95% credible intervals [Crl] 1.11 to 5.89). When considering stone expulsion rate, compared with tamsulosin, silodosin was ranked best (OR 3.58, 95% Crl 1.13 to 11.91), followed by tamsulosin combined with tadalafil (OR 2.55, 95% Crl 1.11 to 5.89) and tadalafil alone (OR 1.86, 95% Crl 0.95 to 4.25). No significant difference was found considering safety profiles between any interventions. This meta-analysis indicates that tamsulosin combined with tadalafil is an effective treatment option for ureteral stones with a low occurrence of side effects. Clinicians should take all known safety and compliance of patients into account when choosing an optimal strategy. Since sample size of included studies, further RCTs are strongly encouraged to address the clinical question.


Assuntos
Inibidores da Fosfodiesterase 5/uso terapêutico , Tadalafila/uso terapêutico , Tansulosina/uso terapêutico , Cálculos Ureterais/tratamento farmacológico , Agentes Urológicos/uso terapêutico , Teorema de Bayes , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Cálculos Ureterais/enzimologia , Cálculos Ureterais/patologia
4.
Dalton Trans ; (8): 1055-64, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18274686

RESUMO

We present herein a high yield, highly selective catalytic synthesis of vinylboronate esters (VBEs), including 1,1-disubstituted VBEs, from alkenes without significant hydrogenation or hydroboration, using the simple catalyst precursor, trans-[RhCl(CO)(PPh3)2] (1), and the diboron reagents B2pin2 (2a, pin = pinacolato = OCMe2CMe2O) or B2neop2 (2b, neop = neopentylglycolato = OCH2CMe2CH2O), or the monoboron reagent HBpin, all of which are commercially available. The reactions were conducted at 80 degrees C using conventional heating, or in a microwave reactor at 150 degrees C.

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