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1.
Phys Rev Lett ; 121(19): 196402, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30468619

RESUMO

Single layers of transition metal dichalcogenides (TMDCs) are excellent candidates for electronic applications beyond the graphene platform; many of them exhibit novel properties including charge density waves (CDWs) and magnetic ordering. CDWs in these single layers are generally a planar projection of the corresponding bulk CDWs because of the quasi-two-dimensional nature of TMDCs; a different CDW symmetry is unexpected. We report herein the successful creation of pristine single-layer VSe_{2}, which shows a (sqrt[7]×sqrt[3]) CDW in contrast to the (4×4) CDW for the layers in bulk VSe_{2}. Angle-resolved photoemission spectroscopy from the single layer shows a sizable (sqrt[7]×sqrt[3]) CDW gap of ∼100 meV at the zone boundary, a 220 K CDW transition temperature twice the bulk value, and no ferromagnetic exchange splitting as predicted by theory. This robust CDW with an exotic broken symmetry as the ground state is explained via a first-principles analysis. The results illustrate a unique CDW phenomenon in the two-dimensional limit.

2.
Nano Lett ; 16(10): 6331-6336, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27648493

RESUMO

Charge density wave (CDW) formation in solids is a critical phenomenon involving the collective reorganization of the electrons and atoms in the system into a wave structure, and it is expected to be sensitive to the geometric constraint of the system at the nanoscale. Here, we study the CDW transition in TiSe2, a quasi-two-dimensional layered material, to determine the effects of quantum confinement and changing dimensions in films ranging from a single layer to multilayers. Of key interest is the characteristic length scale for the transformation from a two-dimensional case to the three-dimensional limit. Angle-resolved photoemission spectroscopy (ARPES) measurements of films with thicknesses up to six layers reveal substantial variations in the energy structure of discrete quantum well states; however, the temperature-dependent band gap renormalization converges at just three layers. The results indicate a layer-dependent mixture of two transition temperatures and a very-short-range CDW interaction within a three-dimensional framework.

3.
Orthod Craniofac Res ; 18 Suppl 1: 8-17, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25865529

RESUMO

OBJECTIVES: Investigate the expression and activity of inflammatory markers in response to different magnitudes of orthodontic forces and correlate this response with other molecular and cellular events during orthodontic tooth movement. SETTING AND SAMPLE POPULATION: CTOR Laboratory; 245 Sprague Dawley male rats. METHODS AND MATERIALS: Control, sham, and 5 different experimental groups received different magnitudes of force on the right maxillary first molar using a coil spring. In the sham group, the spring was not activated. Control group did not receive any appliance. At days 1, 3, 7, 14, and 28, the maxillae were collected for RNA and protein analysis, immunohistochemistry, and micro-CT. RESULTS: There was a linear relation between the force and the level of cytokine expression at lower magnitudes of force. Higher magnitudes of force did not increase the expression of cytokines. Activity of CCL2, CCL5, IL-1, TNF-α, RANKL, and number of osteoclasts reached a saturation point in response to higher magnitudes of force, with unchanged rate of tooth movement. CONCLUSION: After a certain magnitude of force, there is a saturation in the biological response, and higher forces do not increase inflammatory markers, osteoclasts, nor the amount of tooth movement. Therefore, higher forces to accelerate the rate of tooth movement are not justified.


Assuntos
Citocinas/análise , Fios Ortodônticos , Técnicas de Movimentação Dentária/instrumentação , Animais , Fenômenos Biomecânicos , Quimiocina CCL2/análise , Quimiocina CCL5/análise , Imuno-Histoquímica , Mediadores da Inflamação/análise , Interleucina-1/análise , Masculino , Maxila/imunologia , Maxila/patologia , Dente Molar/imunologia , Dente Molar/patologia , Osteoclastos/patologia , Proteínas/análise , Ligante RANK/análise , RNA/análise , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Fator de Necrose Tumoral alfa/análise , Microtomografia por Raio-X/métodos
4.
Nano Lett ; 13(11): 5159-64, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24079848

RESUMO

The low-energy quasiparticles in graphene can be described by a Dirac-Weyl Hamiltonian for massless fermions, hence graphene has been proposed to be an effective medium to study exotic phenomena originally predicted for relativistic particle physics, such as Klein tunneling and Zitterbewegung. In this work, we show that another important particle-physics phenomenon, the neutrino oscillation, can be studied and observed in a particular graphene system, namely, twisted bilayer graphene. It has been found that graphene layers grown epitaxially on SiC or by the chemical vapor deposition method on metal substrates display a stacking pattern with adjacent layers rotated by an angle with respect to each other. The quasiparticle states in two distinct graphene layers act as neutrinos with two flavors, and the interlayer interaction between them induces an appreciable coupling between these two "flavors" of massless fermions, leading to neutrino-like oscillations. In addition, our calculation shows that anisotropic transport properties manifest in a specific energy window, which is accessible experimentally in twisted bilayer graphene. Combining two graphene layers enables us to probe the rich physics involving multiple interacting Dirac fermions.

5.
J Prev Alzheimers Dis ; 11(2): 356-365, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374742

RESUMO

BACKGROUND: Impaired intrinsic capacity (IC), which affects approximately 90% of older adults, is associated with a significantly heightened risk of frailty and cognitive decline. Existing evidence suggests that multidomain interventions have the potential to enhance cognitive performance and yield positive effects on physical frailty. OBJECTIVE: To examine roles of baseline IC and its subdomains on the efficacy of multidomain interventions in promoting healthy aging in older adults. DESIGN: a cluster-randomized controlled trial. SETTING AND PARTICIPANTS: 1,054 community-dwelling older adults from 40 community-based clusters across Taiwan. INTERVENTION: A 12-month pragmatic multidomain intervention of exercise, cognitive training, nutritional counseling and chronic condition management. MEASUREMENTS: Baseline IC was measured by 5 subdomains, including cognition (Montreal Cognitive Assessment, MoCA), sensory (visual and hearing impairment), vitality (handgrip strength or Mini-Nutritional Assessment-short form), psychological well-being (Geriatric Depression Scale-5), and locomotion (6m gait speed). Outcomes of interest were cognitive performance (MoCA scores) and physical frailty (CHS frailty score) over a follow-up period of 6 and 12 months. RESULTS: Of all participants (mean age:75.1±6.4 years, 68.6% female), about 90% participants had IC impairment at baseline (2.0±1.2 subdomains). After covariate adjustment using a generalized linear mixed model (GLMM), the multidomain intervention significantly prevented cognitive declines and physical frailty, particularly in those with IC impairment ≥ 3 subdomains (MoCA: coefficient: 1.909, 95% CI: 0.736 ~ 3.083; CHS frailty scores: coefficient = -0.405, 95% CI: -0.715 ~ -0.095). To assess the associations between baseline poor capacity in each IC subdomain and MoCA/CHS frailty scores over follow-up, a 3-way interaction terms (time*intervention*each poorer IC subdomains) were added to GLMM models. Significant improvements in MoCA scores were shown for participants with poorer baseline cognition (coefficient= 1.138, 95% CI: 0.080 ~ 2.195) and vitality domains (coefficient= 1.651, 95% CI: 0.541 ~ 2.760). The poor vitality domain also had a significant modulating effect on the reduction of CHS frailty score after the 6- and 12-month intervention period (6 months: coefficient= -0.311, 95% CI: -0.554 ~ -0.068; 12 months: coefficient= -0.257, 95% CI: -0.513 ~ -0.001). CONCLUSION AND IMPLICATIONS: A multidomain intervention in community-dwelling older adults improves cognitive decline and physical frailty, with its effectiveness influenced by baseline IC, highlighting the importance of personalized strategies for healthy aging.


Assuntos
Disfunção Cognitiva , Fragilidade , Envelhecimento Saudável , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Masculino , Fragilidade/prevenção & controle , Vida Independente , Força da Mão , Disfunção Cognitiva/prevenção & controle
6.
Proc Natl Acad Sci U S A ; 107(29): 12761-5, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20615989

RESUMO

In this paper, we present the direct observation of quantum size effects (QSE) on the work function in ultrathin Pb films. By using scanning tunneling microscopy and spectroscopy, we show that the very existence of quantum well states (QWS) in these ultrathin films profoundly affects the measured tunneling decay constant kappa, resulting in a very rich phenomenon of "quantum oscillations" in kappa as a function of thickness, L, and bias voltage, V(s). More specifically, we find that the phase of the quantum oscillations in kappa vs. L depends sensitively upon the bias voltage, which often results in a total phase reversal at different biases. On the other hand, at very low sample bias (|V(s)| < 0.03 V) the measurement of kappa vs. L accurately reflects the quantum size effect on the work function. In particular, the minima in the quantum oscillations of kappa vs. L occur at the locations where QWS cross the Fermi energy, thus directly unraveling the QSE on the work function in ultrathin films, which was predicted more than three decades ago. This further clarifies several contradictions regarding the relationship between the QWS locations and the work function.

7.
Nano Lett ; 12(7): 3424-30, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22676724

RESUMO

Graphene is believed to be an excellent candidate material for next-generation electronic devices. However, one needs to take into account the nontrivial effect of metal contacts in order to precisely control the charge injection and extraction processes. We have performed transport calculations for graphene junctions with wetting metal leads (metal leads that bind covalently to graphene) using nonequilibrium Green's functions and density functional theory. Quantitative information is provided on the increased resistance with respect to ideal contacts and on the statistics of current fluctuations. We find that charge transport through the studied two-terminal graphene junction with Ti contacts is pseudo-diffusive up to surprisingly high energies.

8.
Nano Lett ; 12(7): 3833-8, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22716657

RESUMO

The Hofstadter butterfly spectrum for Landau levels in a two-dimensional periodic lattice is a rare example exhibiting fractal properties in a truly quantum system. However, the observation of this physical phenomenon in a conventional material will require a magnetic field strength several orders of magnitude larger than what can be produced in a modern laboratory. It turns out that for a specific range of rotational angles twisted bilayer graphene serves as a special system with a fractal energy spectrum under laboratory accessible magnetic field strengths. This unique feature arises from an intriguing electronic structure induced by the interlayer coupling. Using a recursive tight-binding method, we systematically map out the spectra of these Landau levels as a function of the rotational angle. Our results give a complete description of LLs in twisted bilayer graphene for both commensurate and incommensurate rotational angles and provide quantitative predictions of magnetic field strengths for observing the fractal spectra in these graphene systems.

9.
J Nutr Health Aging ; 27(6): 413-420, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37357324

RESUMO

OBJECTIVES: This study aims to assess the effectiveness of a multidomain intervention program on the change in functional status of hospitalized older adults. DESIGN: This single-arm, prospective, non-randomized interventional study investigates the efficacy of a multidomain interventional program including cognitive stimulation activity, simple exercises, frailty education, and nutrition counseling. SETTING AND PARTICIPANTS: At a tertiary hospital in southern Taiwan, 352 eligible patients were sequentially enrolled. Included patients were aged ≥65 years (mean age, 79.6 ± 9.0 years; 62% male), scored 3-7 on the Clinical Frailty Scale (CFS), and were hospitalized in the geriatric acute ward. INTERVENTION: Those receiving standard care (physical rehabilitation and nutrition counseling) during January-July 2019 composed the historical control group. Those receiving the multidomain intervention during August-December 2019 composed the intervention group. MEASUREMENTS: The primary outcome was the change in activities of daily life (ADL) and frailty status, as assessed by Katz Index and Clinical Frailty Scale, with using the generalized estimating equation model. The length of hospital stay, medical costs, and re-admission rates were secondary outcomes. RESULTS: Participants undergoing intervention (n = 101; 27.9%) showed greater improvements in the ADL and CFS during hospitalization (ADL adjusted estimate, 0.61; 95% CI, 0.11-1.11; p = 0.02; CFS adjusted estimate, -1.11; 95% CI, -1.42- -0.80; p < 0.01), shorter length of hospital stay (adjusted estimate, -5.00; 95% CI, -7.99- -2.47; p < 0.01), lower medical costs (adjusted estimate, 0.58; 95% CI, 0.49-0.69; p < 0.01), and lower 30- and 90-day readmission rates (30-day adjusted OR [aOR], 0.12; 95% CI, 0.27-0.50; p < 0.01; 60-day aOR, 0.04; 95% CI, 0.01-0.33; p < 0.01) than did controls. CONCLUSIONS: Participation in the multidomain intervention program during hospitalization improved the functional status and decreased the hospital stay length, medical costs, and readmission rates of frail older people.


Assuntos
Fragilidade , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Fragilidade/complicações , Estudos Prospectivos , Hospitalização , Tempo de Internação , Pacientes , Avaliação Geriátrica , Idoso Fragilizado
10.
Oral Dis ; 18(3): 307-14, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22151543

RESUMO

OBJECTIVES: Interleukin-8 (IL-8), which is an angiogenic chemokine with a high expression level in tumor tissues, plays important roles in developing many human malignancies including oral squamous cell carcinoma (OSCC). This study was designed to examine the association of IL-8 gene polymorphisms with the susceptibility and clinicopathological characteristics of OSCC. METHODS: A total of 270 patients with OSCC and 350 healthy control subjects were recruited. Four single nucleotide polymorphisms (SNPs) of IL-8 genes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genotyping analysis. RESULTS: Results showed that four IL-8 SNPs (-251 T/A, +781 C/T, +1633 C/T, and +2767 A/T) were not associated with oral cancer susceptibility as well as clinicopathological parameters. But among 345 smokers, IL-8 polymorphisms carriers with betel quid chewing were found to have a 17.41- to 23.14-fold risk to have oral cancer compared to IL-8 wild-type carriers without betel quid chewing. Among 262 betel quid chewers, IL-8 polymorphisms carriers with smoking have a 10.54- to 20.44-fold risk to have oral cancer compared to those who carried wild type without smoking. CONCLUSIONS: Our results suggest that the combination of IL-8 gene polymorphisms and environmental carcinogens might be highly related to the risk of oral cancer.


Assuntos
Carcinoma de Células Escamosas/genética , Interação Gene-Ambiente , Predisposição Genética para Doença/genética , Interleucina-8/genética , Neoplasias Bucais/genética , Polimorfismo Genético/genética , Regiões 3' não Traduzidas/genética , Adenina , Areca/efeitos adversos , Carcinógenos , Carcinoma de Células Escamosas/secundário , Estudos de Casos e Controles , Citosina , Feminino , Genótipo , Humanos , Íntrons/genética , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neovascularização Patológica/genética , Polimorfismo de Fragmento de Restrição/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Fatores de Risco , Fumar/efeitos adversos , Timina
11.
Nano Lett ; 11(7): 2618-21, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21648439

RESUMO

We have performed first-principles calculations to study the lattice vibrational modes and their Raman activities in silicon nanowires (SiNWs). Two types of characteristic vibrational modes are examined: high-frequency optical modes and low-frequency confined modes. Their frequencies have opposite size dependence with a red shift for the optical modes and a blue shift for the confined modes as the diameter of SiNWs decreases. In addition, our calculations show that these vibrational modes can be detected by Raman scattering measurements, providing an efficient way to estimate the size of SiNWs.


Assuntos
Nanotecnologia , Nanofios/química , Semicondutores , Silício/química , Vibração , Análise Espectral Raman
12.
J Exp Med ; 172(3): 673-81, 1990 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1696954

RESUMO

Transforming growth factor alpha (TGF-alpha) is a pleuripotential cytokine with diverse biological effects, including the ability to influence the proliferation of normal cells or neoplastic epithelial cells. Eosinophils are a subset of granulocytes that normally enter the peripheral tissues, particularly those beneath gastrointestinal, respiratory, and urogenital epithelium, where they reside in close proximity to the epithelial elements. In this study, we demonstrate that the great majority of eosinophils infiltrating the interstitial tissues adjacent to two colonic adenocarcinomas and two oral squamous cell carcinomas labeled specifically by in situ hybridization with a 35S-riboprobe for human TGF-alpha (hTGF-alpha). No other identifiable leukocytes in these lesions contained detectable hTGF-alpha mRNA. We also examined leukocytes purified from a patient with the idiopathic hypereosinophilic syndrome. 80% of these eosinophils, but none of the patient's neutrophils or mononuclear cells, were positive for hTGF-alpha mRNA by in situ hybridization, and 55% of these eosinophils were positive by immunohistochemistry with a monoclonal antibody directed against the COOH terminus of the mature hTGF-alpha peptide. Finally, the identification of the purified eosinophil-associated transcript as hTGF-alpha was confirmed by polymerase chain reaction product restriction enzyme analysis followed by Southern blot hybridization. In contrast to eosinophils from the patient with hypereosinophilic syndrome, the peripheral blood eosinophils from only two of seven normal donors had detectable TGF-alpha mRNA and none of these eosinophils contained immunohistochemically detectable TGF-alpha product. Taken together, these findings establish that human eosinophils can express TGF-alpha, but suggest that the expression of TGF-alpha by eosinophils may be under microenvironmental regulation. Demonstration of TGF-alpha production by tissue-infiltrating eosinophils and the eosinophils in the hypereosinophilic syndrome identifies a novel mechanism by which eosinophils might contribute to physiological, immunological, and pathological responses.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Eosinófilos/metabolismo , Neoplasias Bucais/genética , Fatores de Crescimento Transformadores/genética , Sequência de Bases , Northern Blotting , Linhagem Celular , Eosinofilia/sangue , Eosinofilia/genética , Humanos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/genética , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Síndrome , Fatores de Crescimento Transformadores/sangue
13.
Phys Rev Lett ; 104(7): 076807, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20366907

RESUMO

We report on a first-principles study of the conductance through graphene suspended between Al contacts as a function of junction length, width, and orientation. The charge transfer at the leads and into the freestanding section gives rise to an electron-hole asymmetry in the conductance and in sufficiently long junctions induces two conductance minima at the energies of the Dirac points for suspended and clamped regions, respectively. We obtain the potential profile along a junction caused by doping and provide parameters for effective model calculations of the junction conductance with weakly interacting metallic leads.

14.
Eur J Clin Microbiol Infect Dis ; 29(4): 471-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20108018

RESUMO

This nationwide surveillance of clinically important bacteria from the intensive care units (ICUs) of major teaching hospitals throughout Taiwan investigated the susceptibilities to doripenem and other comparator carbapenems from September through November 2005. Minimum inhibitory concentrations (MICs) were determined for 1,311 clinical isolates using the broth microdilution method according to Clinical and Laboratory Standards Institute (CLSI) 2005 guidelines. Doripenem showed similar (within four-fold difference of MICs) in vitro activity to meropenem for Enterobacteriaceae and probably comparable activity to meropenem against important nosocomial non-fermentative Gram-negative bacilli (NFGNBs), including Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia. Among the four carbapenems analysed, doripenem and meropenem exhibited better in vitro activity than imipenem or ertapenem against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates. However, the meropenem MIC(90) against ESBL-producing K. pneumoniae isolates was 2 microg/ml. Besides, doripenem with the MIC(90) of 0.5 microg/ml to Streptococcus pneumoniae possibly suggested its potential therapeutic effect regarding community-acquired pneumonia. Because of the heavy resistance burden in Taiwan, closely monitoring the evolutionary trend of carbapenem susceptibilities against clinically important pathogens is crucial in the future.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/microbiologia , Carbapenêmicos/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Prevalência , Taiwan
15.
Int Endod J ; 43(5): 430-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20518937

RESUMO

AIM: To evaluate the mechanisms of cytotoxicity of chlorhexidine (CHX) in human osteoblastic cells in vitro. METHODOLOGY: Cytotoxicity, cell proliferation and collagen synthesis assays were performed to elucidate the toxic effects of CHX on the human osteoblastic cell line U2OS. To determine whether glutathione (GSH) levels were important in the cytotoxicity of CHX, cells were pre-treated with 2-oxothiazolidine-4-carboxylic acid (OTZ) to boost GSH levels or buthionine sulfoximine (BSO) to deplete GSH. RESULTS: CHX demonstrated a cytotoxic effect to U2OS cells in a dose-dependent manner (P < 0.05). The 50% inhibition concentration of CHX was approximately 0.005%. CHX also inhibited cell proliferation and collagen synthesis (P < 0.05). The addition of OTZ acted as a protective effect on the CHX-induced cytotoxicity (P < 0.05). In contrast, the addition of BSO enhanced the CHX-induced cytotoxicity (P < 0.05). CONCLUSIONS: The levels of CHX tested inhibited cell growth, proliferation and collagen synthesis on U2OS cells. CHX has significant potential for periapical toxicity. GSH depletion might be one of the mechanisms underlying CHX cytotoxicity.


Assuntos
Anti-Infecciosos Locais/toxicidade , Clorexidina/toxicidade , Glutationa/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Anti-Infecciosos Locais/administração & dosagem , Antimetabólitos/farmacologia , Butionina Sulfoximina/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Clorexidina/administração & dosagem , Colágeno/biossíntese , Colágeno/efeitos dos fármacos , DNA/biossíntese , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Corantes Fluorescentes , Glutationa/antagonistas & inibidores , Humanos , Pró-Fármacos/farmacologia , Ácido Pirrolidonocarboxílico/farmacologia , Tiazolidinas/farmacologia
16.
J Nutr Health Aging ; 24(9): 951-958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33155620

RESUMO

OBJECTIVES: To elucidate the hypothetically different interactions between delirium and post-discharge prognostic indicators in elderly hospital inpatients with versus without dementia. DESIGN: Retrospective cohort study of claims data by Taiwan National Health Insurance beneficiaries between 2002-2013. SETTING: Records of public hospital admissions in the Taiwan National Health Insurance Research database. PARTICIPANTS: Propensity-score matched subgroups of patients with delirium superimposed on dementia (n = 922) versus dementia alone (n = 922), delirium alone (n = 680) versus neither delirium nor dementia (n = 680). MEASUREMENTS: Mortality, emergency department visits, readmissions, and psychotropic drug use, within 30, 180, and 365 days of discharge, were analyzed using multivariate proportional hazards or logistic regression analyses. RESULTS: Delirium superimposed on dementia was not associated with increased post-discharge mortality, or emergency department visits, but significantly increased the risk of readmissions at 365-day follow-up (adjusted HR, 95% CI: 1.26, 1.01-1.56). However, delirium without dementia was significantly associated with increased post-discharge mortality, emergency department visits and readmissions at 180 days and 365 days (respective adjusted HRs: mortality, 1.63 and 1.79; adjusted ORs: emergency department visits, 1.89 and 1.81; readmissions, 1.47 and 1.53). Delirium in patients both with dementia and without, was associated with six-fold higher likelihood of in-hospital psychotropic drug use, and doubled post-discharge psychotropic drug usage. CONCLUSIONS: The obvious association between in-hospital delirium and worsened long-term prognosis, irrespective of dementia, raises awareness to warrants proactive and multimodal prevention and intervention strategies. Furthermore, the mechanisms about different influence of delirium for patients with/without dementia need to be further explored.


Assuntos
Demência/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Demência/mortalidade , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Taiwan
17.
J Nutr Health Aging ; 24(2): 160-165, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32003405

RESUMO

OBJECTIVES: To evaluate the negative effect of physical restraint use on the hospital outcomes of older patients. DESIGN: A retrospective cohort study. SETTING: Internal medicine wards of a tertiary medical center in Taiwan. PARTICIPANTS: Subjects aged 65 years and over who were admitted during April to Dec 2017 were recruited for study. MEASUREMENTS: Demographic data, geriatric assessments (polypharmacy, visual impairment, hearing impairment, activities of daily living before and after admission, risk of pressure sores, change in consciousness level, mood condition, history of falls in the previous year, risk of malnutrition and pain) and hospital conditions (admission route, department of admission, length of hospital stay and mortality) were collected for analysis. RESULTS: Overall, 4,352 participants (mean age 78.7±8.7 years, 60.2% = male) were enrolled and 8.3% had physical restraint. Results of multivariate logistic regression showed that subjects with physical restraints were at greater risk of functional decline (adjusted odds ratio 2.136, 95% confidence interval 1.322-3.451, p=0.002), longer hospital stays (adjusted odds ratio 5.360, 95% confidence interval 3.627-7.923, p<0.001) and mortality (adjusted odds ratio 4.472, 95% confidence interval 2.794-7.160, p<0.001) after adjustment for covariates. CONCLUSION: The use of physical restraints during hospitalization increased the risk of adverse hospital outcomes, such as functional decline, longer length of hospital stay and mortality.


Assuntos
Avaliação Geriátrica/métodos , Restrição Física/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização , Humanos , Masculino , Estudos Retrospectivos
18.
Science ; 292(5519): 1131-3, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11349141

RESUMO

We have studied the structural stability of thin silver films with thicknesses of N = 1 to 15 monolayers, deposited on an Fe(100) substrate. Photoemission spectroscopy results show that films of N = 1, 2, and 5 monolayer thicknesses are structurally stable for temperatures above 800 kelvin, whereas films of other thicknesses are unstable and bifurcate into a film with N +/- 1 monolayer thicknesses at temperatures around 400 kelvin. The results are in agreement with theoretical predictions that consider the electronic energy of the quantum well associated with a particular film thickness as a significant contribution to the film stability.

19.
Eur J Clin Microbiol Infect Dis ; 28(2): 215-20, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18716805

RESUMO

To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future.


Assuntos
Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/efeitos dos fármacos , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Taiwan
20.
Eur J Clin Microbiol Infect Dis ; 28(8): 1013-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19280234

RESUMO

A nationwide susceptibility surveillance of Streptococcus pneumoniae and Haemophilus influenzae isolates collected from patients treated at the intensive care units (ICUs) of ten Taiwanese major teaching hospitals was conducted from September 2005 through November 2005. High rates of resistance (intermediate/resistant) of S. pneumoniae to penicillin (85% resistance), ceftriaxone (46%/20%), and cefepime (43%/15%) by meningitis criteria, and in contrast, non-susceptibilities (intermediate/resistant) to penicillin (0%/0%), ceftriaxone (20%/0%) and cefepime (15%/0%) by non-meningitis criteria were noted (p values < 0.05) by the Clinical and Laboratory Standards Institute 2008. Resistant rate of S. pneumoniae to azithromycin was also high (63%). S. pneumoniae isolates were significantly more susceptible to ertapenem (87%) than to imipenem (39%) and meropenem (44%) (p values < 0.05). Rates of non-susceptibilities of H. influenzae isolates to ampicillin and cefaclor were high (55% and 45%, respectively). No beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae isolates were found. Imipenem has a notably higher MIC(90) value (8 microg/ml) for H. influenzae than that of the other two carbapenems. Tigecycline showed good in vitro activities against these two respiratory pathogens. High rates of resistance among isolates of S. pneumoniae and H. influenzae continue to exist in the ICUs of Taiwan.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Streptococcus pneumoniae/isolamento & purificação , Taiwan
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