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1.
Medicina (Kaunas) ; 60(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38929556

RESUMO

Background and Objectives: Although statins are recommended for secondary prevention of acute ischemic stroke, some population-based studies and clinical evidence suggest that they might be used with an increased risk of intracranial hemorrhage. In this nested case-control study, we used Taiwan's nationwide universal health insurance database to investigate the possible association between statin therapy prescribed to acute ischemic stroke patients and their risk of subsequent intracerebral hemorrhage and all-cause mortality in Taiwan. Materials and Methods: All data were retrospectively obtained from Taiwan's National Health Insurance Research Database. Acute ischemic stroke patients were divided into a cohort receiving statin pharmacotherapy and a control cohort not receiving statin pharmacotherapy. A 1:1 matching for age, gender, and index day, and propensity score matching was conducted, producing 39,366 cases and 39,366 controls. The primary outcomes were long-term subsequent intracerebral hemorrhage and all-cause mortality. The competing risk between subsequent intracerebral hemorrhage and all-cause mortality was estimated using the Fine and Gray regression hazards model. Results: Patients receiving statin pharmacotherapy after an acute ischemic stroke had a significantly lower risk of subsequent intracerebral hemorrhage (p < 0.0001) and lower all-cause mortality rates (p < 0.0001). Low, moderate, and high dosages of statin were associated with significantly decreased risks for subsequent intracerebral hemorrhage (adjusted sHRs 0.82, 0.74, 0.53) and all-cause mortality (adjusted sHRs 0.75, 0.74, 0.74), respectively. Conclusions: Statin pharmacotherapy was found to safely and effectively reduce the risk of subsequent intracerebral hemorrhage and all-cause mortality in acute ischemic stroke patients in Taiwan.


Assuntos
Big Data , Hemorragia Cerebral , Inibidores de Hidroximetilglutaril-CoA Redutases , AVC Isquêmico , Humanos , Taiwan/epidemiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Feminino , Masculino , Hemorragia Cerebral/mortalidade , Idoso , Pessoa de Meia-Idade , Estudos de Casos e Controles , Estudos Retrospectivos , AVC Isquêmico/prevenção & controle , AVC Isquêmico/epidemiologia , Idoso de 80 Anos ou mais , Análise de Dados , Fatores de Risco , Pontuação de Propensão
2.
Phys Chem Chem Phys ; 18(40): 28164-28174, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27711586

RESUMO

We studied the excited-state dynamics of trans-4-(N-arylamino)stilbenes with aryl = phenyl (p1H), 4-methoxyphenyl (p1OM), or 4-cyanophenyl (p1CN) in solvents of varied polarity and viscosity by using femtosecond transient absorption and time-correlated single photon counting techniques. In nonpolar solvents the decay is triexponential, in which the rapid component corresponds to vibrational cooling combined with solvation, the intermediate temporal component 41-120 ps to trans-cis isomerization, and the long one ∼1 ns to fluorescence decay of the S1 state. The S1 state has a delocalized geometry and charge-transfer characteristics, corresponding to a planar intramolecular charge transfer (PICT) state. In polar solvents, an excited-state absorption band appears near 520 and 480 nm for p1OM and p1CN, respectively but not for p1H. This band has a rise lifetime of 4.3/7.5, 16.3/9.4, and 29.5/16 ps for p1CN/p1OM in acetonitrile (ACN), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), respectively and matches the decay of the 600 nm PICT band. This band is thus assigned to the absorption of a singlet twisted intramolecular charge transfer state (TICT). The conversion rate decreases as the solvent viscosity is increased and is consistent with a large structural variation amplitude. Theoretical calculations using density functional theory (DFT), method PEB0, were employed to obtain the optimized structures and energies of those states. The PICT state possesses delocalized π electrons along the molecule. The TICT for p1CN is formed by twisting about the aminostilbene-benzonitrile C-N bond by ∼90°, but it is about the stilbene-aniline C-N bond for p1OM. We observed faster conversion rates for p1CN in alcoholic solvents, in which the lifetimes for both the PICT and TICT states are shortened to 20-99 ps and 120-660 ps, respectively, as a result of solvent-solute H-bonding interactions. In p1OM, the TICT state has an elongated C[double bond, length as m-dash]C bond in the stilbene moiety, which might facilitate the trans-cis isomerization reaction and thus account for the relatively short lifetime of 58-420 ps in polar solvents.

3.
Chemistry ; 20(45): 14826-33, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25212481

RESUMO

Dependence of the backbone planarity of oligo(p-phenyleneethynylene)s (OPEs) on the intrinsic electronic character of substituents and on the nature of the solvent has been experimentally demonstrated with a series of center-symmetrical five-ring systems, pentiptycene-pentiptycene-arene-pentiptycene-pentiptycene, differing in the substituents on the central arene. In frozen 2-methyltetrahydrofuran (MTHF), the adjacent pentiptycene units prefer to be in a mutually twisted orientation when the substituents are electron-withdrawing (F and amido), resulting in a TPPT or TTTT conformation, whereas a planarized PPPP backbone is favored in the case of electron-donating substituents (alkyl and alkoxy). The propensity to adopt the PPPP form is generally enhanced by replacing MTHF with either methylcyclohexane or mixed ethanol/methanol as solvent. These observations reveal that the twist between adjacent pentiptycene units in OPEs is a consequence of the electronic rather than steric effects of iptycenyl substituents. The electronic effect of iptycenyl substituents is manifested in decreased phenylene π polarizability as the net effect of both electron-donating hyperconjugation and an electron-withdrawing inductive effect. Variable-temperature electronic absorption and emission spectroscopies are the critical tools for this work. Our findings provide important guidelines for conformational and electronic engineering of OPEs and for the design of novel iptycene-based organic electronic materials.

4.
J Phys Chem A ; 117(15): 3158-64, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23514591

RESUMO

A constrained model compound of trans-4-(N,N-dimethylamino)-4'-nitrostilbene (DNS), namely, compound DNS-B3 that is limited to torsions about the phenyl-nitro C-N bond and the central C═C bond, was prepared to investigate the structural nature of the radiative and nonradiative states of electronically excited DNS. The great similarities in solvent-dependent electronic spectra, fluorescence decay times, and quantum yields for fluorescence (Φf) and trans → cis photoisomerization (Φtc) between DNS and DNS-B3 indicate that the fluorescence is from a planar charge-transfer state and torsion of the nitro group is sufficient to account for the nonradiative decay of DNS. This conclusion is supported by TDDFT calculations on DNS-B3 in dichloromethane. The structure at the conical intersection for internal conversion is associated with not only a twisting but also a pyramidalization of the nitro group. The mechanism of the NO2 torsion is discussed in terms of the effects of solvent polarity, the substituents, and the volume demand. The differences and analogies of the NO2- vs amino-twisted intramolecular charge-transfer (TICT) state of trans-aminostilbenes are also discussed.

5.
World Neurosurg ; 178: e431-e444, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506843

RESUMO

OBJECTIVE: Adequate brain swelling resolution prior to cranioplasty (CP) is an important yet loosely defined issue. Despite efforts to balance timely CP and patient safety, heterogeneous study methodologies have led to conflicting results. This study aims to standardize this issue through quantifying degree of brain swelling resolution using a proposed Visual CP Scale. METHODS: The proposed Visual CP Scale is validated through a 2-pronged approach. The first prong involves a national survey in Taiwan, where neurosurgeons were surveyed to determine what constitutes a patient's readiness for CP. The second prong involves a large retrospective cohort, where the correlations between timing, degree of brain swelling resolution, and post-CP complication rates, are evaluated. RESULTS: In the national Taiwan CP Survey, 124 out of 772 neurosurgeons (17.2%) completed the survey. Respondents who chose higher grades on the Visual CP Scale preferred later CP timings. In the retrospective data, 378 out of 770 (49.1%) patients had pre-CP brain images, allowing for the utilization of the Visual CP Scale. A Visual CP Scale score of greater than or equal to 4 was associated with fewer complications after CP. CONCLUSIONS: The timing of CP should be determined by the degree of brain swelling resolution, not vice versa. The proposed Visual CP Scale offers an objective method for assessing brain swelling resolution, making it an adjuvant tool for clinical decision-making and future research related to CP.

6.
J Phys Chem A ; 115(15): 3233-42, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21434668

RESUMO

The excited-state behavior of a series of trans-2-(N-arylamino)stilbenes (aryl = phenyl (o1H), 4-methylphenyl (o1Me), 4-methoxyphenyl (o1OM), and 4-cyanophenyl (o1CN)) and trans-2-(N,N-diphenylamino)stilbene (o2) in both nonpolar and polar solvents is reported and compared to that of the parent trans-2-aminostilbene and the corresponding meta- and para-isomers (m1R and p1R, where R = H, Me, OM, and CN, and m2 and p2). Two types of torsional motions, the D-A torsion that results in a nonfluorescent twisted intramolecular charge transfer (TICT) state and the C═C torsion that leads to the cis isomers, account for the radiationless decays of o1R and o2. The relative efficiencies of these torsions can be readily evaluated from their quantum yields for fluorescence (Φ(f)) and trans → cis isomerization (Φ(tc)). The propensities of the D-A torsion are similar for the ortho and meta isomers, which is 1OM > 1Me and negligible for 1H, 1CN, and 2. The activation parameters determined from temperature-dependent fluorescence lifetimes suggest that the C═C torsion occurs mainly via the triplet state for the ortho systems, a behavior again similar to that of the meta isomers. Whereas the intersystem crossing in o1R, m1R, and m2 is essentially a nonactivated process, it encounters a barrier of 2.7-3.8 kcal mol(-1) in o2. As a result of the barriers that decelerate the radiationless decays and the slow fluorescence rate for o2 in acetonitrile, the observed long fluorescence lifetime 24.5 ns at room temperature reaches a new record for unconstrained trans-stilbenes.


Assuntos
Estilbenos/química , Estrutura Molecular , Fotoquímica , Teoria Quântica , Estereoisomerismo , Estilbenos/síntese química
7.
Risk Manag Healthc Policy ; 14: 2995-3001, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285613

RESUMO

BACKGROUND: Osteoporotic fractures are a significant cause of morbidity and mortality affecting population worldwide. All guidelines recommended vertebral fracture assessment by dual-energy X-ray absorptiometry (DXA). This study aimed at evaluation of any associated benefits of screening with DXA in patients who had received vertebroplasty in Taiwan. METHODS: Data were obtained from the National Health Insurance Research Database (NHIRD) in Taiwan. We retrospectively compared the data of patients, who were admitted for vertebroplasty, whether they received DXA screening or not. The outcomes of interest were recurrence of spinal fracture and mortality during a follow-up period of 10 years. RESULTS: From this Taiwan national database, the screening rate of osteoporosis in patient who received vertebroplasty was 11.7%. The mean age in the non-DXA screened cohort (n=32,986) was 74.03±12.21 years (71.98% female). In the DXA screened cohort (n=4361), the mean age was 76.43±9.19 years (79.91% female). During the 10-year follow-up period, after matching, non-DXA patients had significantly higher mortality rates than their DXA counterparts, which were 42.37% and 37.73% (p-value < 0.0001), respectively. The re-fracture rates between non-DXA and DXA patients were not significantly different at 17.26% and 16.89% (p-value = 0.1766), respectively. CONCLUSION: The rate of DXA screening before patients receiving vertebroplasty was extremely low, at 11.7%. Our results showed that DXA screening before vertebroplasty in spinal fractures patients had lower mortality. From this national retrospective cohort study, routine screening of osteoporosis in spinal fracture patients can lead to reduction in mortality.

8.
Risk Manag Healthc Policy ; 14: 177-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33488130

RESUMO

BACKGROUND: Statin treatment improves clinical outcomes in patients with ischemic strokes, although there is no evidence regarding the safety of statin therapy in patients with intracerebral hemorrhage (ICH). This study aimed at evaluating the effects of continuing statin treatment after ICH. METHODS: Data were obtained from the National Health Insurance Research Database in Taiwan. We retrospectively compared the data of patients with and without statin exposure after ICH. The outcomes of interest were recurrence of hemorrhagic stroke and mortality during a follow-up period of 10 years. RESULTS: During the 10-year follow-up period, the mortality rate was 32.73% in the statin group and 42.77% in the non-statin group. Statin therapy in patients with acute ICH with dyslipidemia can decrease mortality. CONCLUSION: Statin therapy reduced the risk of 10-year mortality in patients who experienced acute hemorrhagic stroke.

9.
J Org Chem ; 75(22): 7877-86, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-20973531

RESUMO

The synthesis, electronic properties, and performance in dye-sensitized solar cells (DSSCs) of four cone-shaped organic dyes (ITD, ITD-Th, ITD-Hx, and ITD-OM) containing the isotruxene π-scaffold are reported. Selective substitution of the unsymmetrical isotruxene core with two diarylamino donors and one cyanocarboxylic acid acceptor was achieved by using a prefunctionalized dibromoisotruxene building block. The ortho-para-branched isotruxene core allows strong electronic couplings among the donors and the acceptor, leading to red-shifted absorption profiles with significant charge-transfer character. All four isotruxene dyes display reversible anodic waves in cyclic voltammagrams with both HOMO and LUMO potentials suitable for application in DSSCs. The DSSCs fabricated with these cone-shaped organic dyes exhibited high open-circuit voltages (0.67-0.76 V) and fill factors (0.67-0.72) with a power conversion efficiency (η) up to 5.45%, which is 80% of the ruthenium dye N719-based standard cell fabricated and measured under the same conditions.

10.
Comput Methods Programs Biomed ; 188: 105250, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31838341

RESUMO

BACKGROUND AND OBJECTIVES: Minimally-invasive total knee arthroplasty (MIS-TKA) has demonstrated very good short-term success, but its mid- to long-term results remain inconclusive. The success may be related to the tradeoff between a small incision and accurate positioning of the implant components. Patient-specific instrumentation (PSI) aims to improve the accuracy in restoring the knee axis and the clinical outcomes for MIS-TKA, but the results are yet to be confirmed by accurate assessment during functional activities. The purpose of the current study was to measure and compare the in vivo three-dimensional (3D) rigid-body and surface kinematics of MIS-TKA implanted with and without PSI during isolated knee active flexion/extension and sit-to-stand using state-of-the-art 3D model-based fluoroscopy technology. METHODS: Ten patients treated for advanced medial knee osteoarthritis by MIS-TKA without PSI (non-PSI group) and nine with PSI (PSI group) participated in the current study. Each subject performed non-weight-bearing knee flexion/extension and sit-to-stand tasks while the motion of the prosthetic knee was under bi-plane fluoroscopy surveillance. The computer models of each of the knee prosthesis components were registered to the measured fluoroscopy images for each time frame via a novel validated 3D fluoroscopy method. Non-parametric 1-tailed Mann-Whitney tests were performed to detect the differences in the joint and surface kinematic variables every 10° of knee flexion between the non-PSI and PSI groups. The 1-tailed significance level was at α = 0.05. RESULTS: The PSI group showed clear, coupled flexion/internal rotation during activities, while the non-PSI group remained roughly at an externally rotated position with slight internal rotations. The coupled rotation in the PSI group was accompanied by an anterior displacement of the medial contact and a posterior displacement of the lateral contact, which was different from the screw-home mechanism. Neither of the two groups showed the normal roll-back phenomenon, i.e., posterior translation of the femur relative to the tibia during knee flexion. CONCLUSIONS: With the state-of-the-art 3D fluoroscopy method, differences in both the rigid-body and surface kinematics of the prosthetic knees between MIS-TKA with and without PSI were identified. Patients with PSI demonstrated significant positive effects on the reconstructed rigid-body kinematics of the knee, showing clearer coupled flexion/internal rotations - an important kinematic characteristic in healthy knees - than those without PSI during activities with or without weight-bearing. However, none of them showed normal contact patterns. The current findings will be helpful for surgical instrument design, as well as for surgical decision-making in MIS total knee arthroplasty.


Assuntos
Artroplastia do Joelho , Fluoroscopia , Procedimentos Cirúrgicos Minimamente Invasivos , Osteoartrite do Joelho/diagnóstico por imagem , Idoso , Fenômenos Biomecânicos , Feminino , Fêmur/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Joelho/fisiopatologia , Articulação do Joelho/fisiopatologia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Suporte de Carga
11.
J Phys Chem A ; 113(17): 4868-77, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-19354224

RESUMO

The synthesis, X-ray crystal structures, and photochemical behavior of a series of methyl- and ethylene-bridge-substituted trans-4-(N-(4-cyanophenyl)amino)stilbenes (3-8) are reported and compared to those of the parent compound 1CN. Aminostilbene 1CN displays dual fluorescence in polar solvents due to planar and twisted intramolecular charge-transfer (PICT and TICT) states. Alkyl substitution on the stilbene group of 1CN significantly perturbs its photochemistry, including fluorescence, trans --> cis photoisomerization, and TICT state formation. The alkyl substituent effect can be dissected into electronic and steric influences, and both are position dependent, which is vinyl alpha-carbon > vinyl beta-carbon > phenyl o-carbon. The main outcome of the alkyl substituent effect is to lower the barrier for the singlet-state photoisomerization. As a result, the quantum yield for photoisomerization is increased, and that for fluorescence is reduced. The corresponding quantum yield for TICT state formation in polar solvents is reduced only when significant ground-state twisting (a steric influence) is present. The alkyl substitution exerts little or no effect on the rate of intersystem crossing.

12.
World Neurosurg ; 132: 309-313, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31525482

RESUMO

INTRODUCTION: Rosai-Dorfman disease (RDD) is a rare disease that can be triggered by either viral or bacterial infection. Several parts of the body can be involved, from the central nervous system to the pelvic regions had been reported. At present, there is a serious lack of guidelines as to how to treat cases of RDD involving the spine. Current trends show that surgery remains the first method of choice to cure this disease, but in refractory or recurrent RDD, repeat surgery cannot guarantee total resection. Under such circumstances, adjuvant therapy can be very useful. Here, we share our experience of treating recurrent spinal RDD. CASE DESCRIPTION: Our patient was a 32-year-old male patient with hepatitis B virus infection. He suffered from lower back pain with lower limb weakness after being hit by a metal pipe. Laminectomy of T11-12 was performed to decompress the spinal cord. The final pathological results demonstrated chronic inflammation. After surgery, the lower limbs improved and the patient recovered quite well. However, he returned 3 years later with the same complaints and was diagnosed with RDD. Durectomy was performed and repaired with an artificial dura. Thalidomide therapy was initiated. Currently, 9 years later, the patient has not experienced recurrence or any form of neurological deficit. CONCLUSIONS: RDD is a rare disease and can be misdiagnosed easily. Although it may resolve spontaneously, recurrence is possible. Hence, extensive follow-up is necessary. Surgery remained the first choice of surgery, however, when encountered recurrent or nonresectable RDD, adjuvant therapy such as corticosteroids, thalidomide, and radiotherapy could help. In this article, we shared our experience using thalidomide in treating nonresectable RDD.


Assuntos
Histiocitose Sinusal/terapia , Imunossupressores/uso terapêutico , Doenças da Coluna Vertebral/terapia , Talidomida/uso terapêutico , Vértebras Torácicas/cirurgia , Adulto , Histiocitose Sinusal/complicações , Histiocitose Sinusal/diagnóstico por imagem , Histiocitose Sinusal/patologia , Humanos , Dor Lombar/etiologia , Extremidade Inferior , Masculino , Debilidade Muscular/etiologia , Recidiva , Doenças da Coluna Vertebral/complicações , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças da Coluna Vertebral/patologia
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