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1.
Osteoporos Sarcopenia ; 10(1): 3-10, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38690538

RESUMO

Objectives: This study aimed to present the Asia-Pacific consensus on long-term and sequential therapy for osteoporosis, offering evidence-based recommendations for the effective management of this chronic condition. The primary focus is on achieving optimal fracture prevention through a comprehensive, individualized approach. Methods: A panel of experts convened to develop consensus statements by synthesizing the current literature and leveraging clinical expertise. The review encompassed long-term anti-osteoporosis medication goals, first-line treatments for individuals at very high fracture risk, and the strategic integration of anabolic and antiresorptive agents in sequential therapy approaches. Results: The panelists reached a consensus on 12 statements. Key recommendations included advocating for anabolic agents as the first-line treatment for individuals at very high fracture risk and transitioning to antiresorptive agents following the completion of anabolic therapy. Anabolic therapy remains an option for individuals experiencing new fractures or persistent high fracture risk despite antiresorptive treatment. In cases of inadequate response, the consensus recommended considering a switch to more potent medications. The consensus also addressed the management of medication-related complications, proposing alternatives instead of discontinuation of treatment. Conclusions: This consensus provides a comprehensive, cost-effective strategy for fracture prevention with an emphasis on shared decision-making and the incorporation of country-specific case management systems, such as fracture liaison services. It serves as a valuable guide for healthcare professionals in the Asia-Pacific region, contributing to the ongoing evolution of osteoporosis management.

3.
Osteoporos Sarcopenia ; 4(1): 16-21, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30775536

RESUMO

OBJECTIVES: Hip fracture is a major public health problem. Earlier studies projected that the total number of hip fracture will increase dramatically by 2050, and most of the hip fracture will occur in Asia. To date, only a few studies provided the updated projection, and none of them focused on the hip fracture projection in Asia. Thus, it is essential to provide the most up to date prediction of hip fracture in Asia, and to evaluate the total direct medical cost of hip fracture in Asia. METHODS: We provide the updated projection of hip fracture in 9 Asian Federation of Osteoporosis Societies members using the most updated incidence rate and projected population size. RESULTS: We show that the number of hip fracture will increase from 1,124,060 in 2018 to 2,563,488 in 2050, a 2.28-fold increase. This increase is mainly due to the changes on the population demographics, especially in China and India, which have the largest population size. The direct cost of hip fracture will increase from 9.5 billion United State dollar (USD) in 2018 to 15 billion USD in 2050, resulting a 1.59-fold increase. A 2%-3% decrease in incidence rate of hip fracture annually is required to keep the total number of hip fracture constant over time. CONCLUSIONS: The results show that hip fracture remains a key public health issue in Asia, despite the available of better diagnosis, treatment, and prevention of fracture over the recent years. Healthcare policy in Asia should be aimed to reduce the burden of hip fracture.

4.
J Colloid Interface Sci ; 450: 434-445, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25867680

RESUMO

HYPOTHESIS: As more sodium dodecylsulfate (SDS) monomers adsorb at the water/titanium dioxide (TiO2) nanoparticles interface, the particles become more stable against agglomeration and sediment more slowly. SDS micelles are not expected to adsorb on the particles and affect the stability against agglomeration or sedimentation. Since micelles are smaller than the 300 nm TiO2 nanoparticles studied, they may introduce depletion forces which may affect the dispersion stability. EXPERIMENTS AND MODELS: Sedimentation times were measured in water and in 100 mM NaCl for SDS concentrations from 0.1 to 200 mM. Adsorption densities of SDS and zeta potentials of particles were measured. Dynamic light scattering was used to measure average diameters of particles or particle agglomerates. Modeling of sedimentation/diffusion was done to predict sedimentation times of particles. Modeling of agglomeration rates was done to help predict sedimentation rates of clusters. FINDINGS: At SDS concentrations close to or above the cmc, up to 60 mM in water or 115 mM in 100 mM NaCl, the nanoparticles sediment most slowly without any agglomeration. At higher micelle concentration, SDS micelle depletion forces are very strong, causing fast flocculation, without coagulation. Then sedimentation occurs much faster. The effective micelle depletant size includes about 4 Debye lengths of the charged micelles or particles.

5.
Chin Med J (Engl) ; 126(12): 2333-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23786949

RESUMO

BACKGROUND: Telbivudine, one of the five nucleos(t)ide antiviral drugs, was reported to be superior to lamivudine in a better biochemical, virological, and histological response for treatment-naive patients in the GLOBE trial. The aim of this study was to determine the antiviral potency, viral resistance, and the signifcance of early response for long-term telbivudine treatment. METHODS: We recruited 161 patients of chronic hepatitis B (CHB) on telbivudine between January 2009 and September 2011 in Macau, China. The serum hepatitis B virus DNA levels, hepatitis B e antigen (HBeAg) seroconversion, alanine aminotransferase (ALT) normalization, and viral resistance were analyzed. RESULTS: The median age and follow-up duration were 48 years and 16.9 months. All patients were followed up for at least 6 months, while data were collected for 132, 120, 95, and 53 patients at 12, 24, 48, and 96 weeks respectively. The cumulative HBeAg seroconversion rate was 20.8% and only three patients (1.9%) presented with telbivudine low level resistance. The ALT normalization rates were 76.9% at 48 weeks and 77.6% at 96 weeks. Undetectable HBV DNA was achieved by 1.8%, 31.6%, 60%, and 74.1% in HBeAg positive patients and 29.3%, 60.3%, 84%, and 84.6% in HBeAg negative patients at each time point. Week 12 HBV DNA level < 1000 copies/ml (< 200 IU/ml) was a better predictor of viral suppression at 2-year follow-up (P = 0.001, OR = 27.00) than undetectable HBV DNA level at week 24 (P = 0.120, OR = 4.81). CONCLUSIONS: Two-year telbivudine treatment yielded high rates of viral suppression and ALT normalization. Serum HBV DNA level at week 12 is a superior predictor for long-term viral suppression.


Assuntos
Antivirais/uso terapêutico , DNA Viral/sangue , Hepatite B Crônica/tratamento farmacológico , Timidina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Farmacorresistência Viral , Feminino , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Telbivudina , Timidina/uso terapêutico , Fatores de Tempo
6.
J Chem Theory Comput ; 8(8): 2824-34, 2012 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26592123

RESUMO

We report a database of 18 ylidic bond dissociation energies obtained by using highly accurate quantum mechanical methods, and we use it to test approximate electronic structure methods. The new benchmark database is called YBDE18 and is used to test a large number of electronic structure methods, including eight wave function methods and 98 density functional exchange-correlation functionals. Among them, we include some very recent density functionals, including the SOGGA11 GGA functional, the SOGGA11-X hybrid GGA functional, the M11-L local meta-GGA functional, and the M11 range-separated hybrid meta-GGA functional. We also consider other functionals of these classes plus a local spin density approximation, global-hybrid meta-GGAs, range-separated hybrid GGAs, doubly hybrid GGAs, and doubly hybrid meta-GGAs. We found M05-2X-D3, MPWB1K-D3, M05-2X, LC-BLYP, PBE0-D3, and MC3MPWB to be the best DFT methods for this database. Although they do not place in the top four overall, our new-generation functionals show overall competitive performances; each of the new functionals provides the smallest mean signed error within its class, while in terms of mean unsigned errors, SOGGA11 is the best GGA, and SOGGA11-X and M11-L are among the first three best functionals in their categories, global-hybrid GGA and local meta-GGA. The best local functionals are VSXC and M06-L, the best global-hybrids are M05-2X, M08-HX, M06-2X, and MPWB1K, and the best range-separated hybrids are LC-BLYP, ωB97, ωB97X, and M11.

7.
J Colloid Interface Sci ; 362(1): 33-41, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21742340

RESUMO

The effect of Triton X-100 on the colloidal dispersion stability of CuPc-U (unsulfonated and hydrophobic) and CuPc-S (surface sulfonated and hydrophilic) particles in aqueous solutions (water and NaNO(3)) was investigated at 25 °C. Its adsorption density was determined from surfactant concentrations analyzed by an HPLC method with a UV detector. The experimental dispersion stability ratios of the particles were determined from dynamic light scattering (DLS) data, with the Rayleigh-Debye-Gans (RDG) light scattering theory. The adsorption densities of Triton X-100 on both the CuPc-U and CuPc-S increase with increasing concentration of surfactant up to the critical micelle concentration (cmc), and then reach a plateau. The maximum adsorption density Γ(m) is higher for the CuPc-U (d(h)=160 nm) than that for the CuPc-S (d(h)=90 nm). The hydrophobic chains are inferred to be adsorbed onto the surfaces, and the hydrophilic ethylene oxide chains are in a coil conformation. The W(app)-values for the CuPc-U dispersions are affected mainly by the surfactant fractional surface coverage θ. Adding NaNO(3) has no significant effect on the dispersion stability. The stabilization mechanism for the CuPc-U is inferred to be primarily steric, as expected. The stability ratios for the CuPc-S in solutions with NaNO(3) are higher than those for CuPc-U, and decrease with increasing concentration of NaNO(3), indicating that the stabilization is affected by the screening of electrostatic repulsive forces. The zeta potential is not a good predictor of the electrostatic stabilization, pointing to the need for new and improved theories.

8.
Langmuir ; 26(10): 6995-7006, 2010 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-20073525

RESUMO

The dispersion stability and the zeta potentials of nonspherical crystalline (beta-form) copper phthalocyanine (CuPc) particles of hydrodynamic diameter d(h) approximately = 90 nm were investigated at 25 degrees C in water and in aqueous solutions of NaNO(3). The electrolyte concentrations c ranged from 1 to 500 mM and the particle concentrations ranged from 50 to 10,000 ppm (0.005 to 1 wt %). In each case, the Fuchs-Smoluchowski stability ratio W was determined from dynamic light scattering (DLS) data and the Rayleigh-Debye-Gans (RDG) scattering theory. The data suggest that electrostatic effects play a major role in the stability of CuPc-based dispersions. The calculated particle charge z per CuPc particle based on the zeta potential data and the area of the particles (assumed to be cubical) suggests that there is preferential adsorption of NO(3)(-) ions on the uncharged CuPc surface, and the surface charge increases with increasing electrolyte concentration. Furthermore, two new models of the DLVO theory, for spheres and for parallel face-to-face cubes, were reformulated in dimensionless form. The Hamaker constant of CuPc particles was calculated by the same authors on the basis of theoretical models in J. Chem. Theory Comput. (2010, in press). The key dimensionless group is the ratio N of the electrostatic double layer energy to the Hamaker constant. The two DLVO models were used to predict the value of a dimensionless maximum potential energy Phi(max), the conditions when it may exist, and then the value of W. In water, the DLVO model for spheres overpredicted the stability, while the model for cubes underpredicted the stability. At c = 1 mM, both models overpredicted the stability. At c = 10 mM, the model for spheres underpredicted the stability, whereas the model for cubes overpredicted the stability. Hence, there seems to be some significant shape effects on the electrostatic stabilization of CuPc particle dispersions. At c = 100 and 500 mM, both models underpredicted the stability substantially, suggesting the existence of additional short-range repulsive forces, which may primarily control the stability. Simple sensitivity analysis on the calculations supported these conclusions.


Assuntos
Indóis/química , Modelos Químicos , Compostos Organometálicos/química , Coloides/química , Concentração de Íons de Hidrogênio , Luz , Nitratos/química , Tamanho da Partícula , Espalhamento de Radiação , Soluções , Propriedades de Superfície , Água/química
9.
J Chem Theory Comput ; 6(2): 491-8, 2010 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26617304

RESUMO

A time-dependent density functional theory (TDDFT) scheme has been validated for predictions of the dispersion coefficients of five molecules (H2O, NH3, CO2, C6H6, and pentane) and for predictions of the static dipole polarizabilities of three organometallic compounds (TiCl4, OsO4, and Ge(CH3)4). The convergence of grid spacing has been examined, and two types of pseudopotentials and 13 density functionals have been tested. The nonretarded Hamaker constants A11 are calculated by employing a semiempirical parameter a along with the standard Hamaker constant equation. The parameter a is optimized against six accurate Hamaker constants obtained from the full Lifshitz theory. The dispersion coefficients of copper phthalocyanine CuPc and CuPc-SO3H are then computed. Using the theoretical densities of ρ1 = 1.63 and 1.62 g/cm(3), the Hamaker constants A11 of crystalline α-CuPc and ß-CuPc are found to be 14.73 × 10(-20) and 14.66 × 10(-20) J, respectively. Using the experimentally derived density of ρ1 = 1.56 g/cm(3) for a commercially available ß-CuPc (nanoparticles of ∼90 nm hydrodynamic diameter), A11 = 13.52 × 10(-20) J is found. Its corresponding effective Hamaker constant in water (A121) is calculated to be 3.07 × 10(-20) J. All computed A11 values for CuPc are noted to be higher than those reported previously.

10.
J Chem Theory Comput ; 5(10): 2726-33, 2009 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26631785

RESUMO

We present benchmark energetic data for the HCOOH···benzene complexes. The benchmark data were determined by a composite approach based on CCSD(T) calculations. Final binding energies (kcal/mol) are in the range of 1.6-4.8 kcal/mol, and they were used as reference data to test density functionals in the literature. Among the tested local density functionals without empirical dispersion corrections, M06-L is the best performing functional, and M06-L/6-31+G(d,p) gives a mean unsigned error (MUE) of only 0.15 kcal/mol. PBEsol and SOGGA also show promising performance. The best local DFT-D methods are BLYP-D and PBEsol-D, and they give an MUE of 0.15 kcal/mol after removing basis set superposition errors by the counterpoise approach. Empirical dispersion corrections greatly improve the descriptions of noncovalent interactions in HCOOH···benzene dimers. The calculated benchmark data and intermolecular potential are useful for the parametrizations of new force fields and coarse-grained models for chemical species such as the acrylic polymers.

11.
Chin Med Sci J ; 23(4): 230-3, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19180884

RESUMO

OBJECTIVE: To study the clinical and genetic features of familiar amyloid polyneuropathy (FAP). METHODS: Three families of suspected FAP in China mainland and Macau were investigated on aspects of clinical manifestations, histological features, and gene analysis. RESULTS: All the 3 families had the clinical features of sensory and motor polyneuropathies, and notable vegetative nerve involvements. Affected cases of one family had ultrasound proved cardiomyopathy. Histological studies showed amyloid deposition in all the biopsy tissues of the affected cases of the 3 families, and anti-transthyretin antisera staining was positive in 3 cases of one family. Gene analysis confirmed that mutation types were amyloidogenic transthyretin (ATTR) Val30Met, Phe33Val, and Gly67Glu in the 3 families respectively. The ATTR Gly67Glu family had a shorter survival time due to the heart involvement compared with the other 2 families. CONCLUSION: FAP is an autosomal dominant inherited disease, with its clinical manifestations related to the type of genetic mutation.


Assuntos
Neuropatias Amiloides Familiares/genética , Análise Mutacional de DNA , Pré-Albumina/genética , Adulto , Neuropatias Amiloides Familiares/patologia , China , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Fenótipo
12.
Methods Mol Biol ; 300: 191-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15657485

RESUMO

This chapter reviews the recent development in biological sensing using nanotechnologies based on carbon nanotubes and various nanowires. These 1D materials have shown unique properties that are efficient in interacting with biomolecules of similar dimensions, i.e., on a nanometer scale. Various aspects including synthesis, materials properties, device fabrication, biofunctionalization, and biological sensing applications of such materials are reviewed. The potential of such integrated nanobiosensors in providing ultrahigh sensitivity, fast response, and high-degree multiplex detection, yet with minimum sample requirements is demonstrated. This chapter is intended to provide comprehensive updated information for people from a variety of backgrounds but with common interests in the fast-moving interdisciplinary field of nanobiotechnology.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanotubos de Carbono , Técnicas Biossensoriais/métodos , DNA/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia de Varredura por Sonda , Nanotubos de Carbono/ultraestrutura , Paládio , Peptídeos/análise
13.
Biosens Bioelectron ; 19(1): 43-9, 2003 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-14558997

RESUMO

In this paper, a mediatorless amperometric glucose biosensor based on direct covalent immobilisation of monomolecular layer of glucose oxidase (GOx) on a semiconducting indium-tin oxide (ITO) is demonstrated. The abundance of surface hydroxyl functional group of ITO allows it to be used as a suitable platform for direct covalent immobilisation of the enzyme for sensor architecture. The anodic current corresponding to electrochemical oxidation of the enzymatic product, hydrogen peroxide, at a sputtered Pt electrode at 0.500 V (vs. SCE) was obtained as the sensor signal. It was found that the biosensor based on the direct immobilisation scheme shows a fast biosensor response, minimum interference from other common metabolic species and ease of biosensor miniaturisation. A linear range of 0-10 mM of glucose was demonstrated, which exhibits a high sensitivity as far as performance per immobilised GOx molecule is concerned. A detection limit as low as 0.05 mM and long-term stability were observed. Even more important, the biosensor design allows fabrication through a dry process. These characteristics make it possible to achieve mass production of biosensor compatible with the current electronic integrated circuit manufacturing technologies.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Glucose Oxidase/química , Glucose/análise , Glucose/química , Microquímica/instrumentação , Compostos de Estanho/química , Adsorção , Técnicas Biossensoriais/métodos , Glicemia/análise , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Eletroquímica/métodos , Eletrodos , Enzimas Imobilizadas/química , Desenho de Equipamento , Análise de Falha de Equipamento , Microquímica/métodos , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Nanotechnology ; 14(12): 1239-45, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21444977

RESUMO

We report the detection of DNA PCR amplicons using an ultrasensitive label-free electronic technique based on multiwalled carbon nanotube (MWNT) nanoelectrode arrays embedded in an SiO(2) matrix. Specific PCR amplicons are reliably detected using electrochemical (EC) methods through allele-specific oligonucleotide hybridization. The inherent guanine bases in the DNA amplicon target of [Formula: see text] bases serve as signal moieties with the aid of Ru(bpy)(3)(2+) mediators, providing an amplified anodic current associated with the oxidation of guanine groups at the nanoelectrode surface. The reduced size and density of the nanoelectrode array provided by MWNTs dramatically improves the sensitivity of EC detection. In addition, the abundant guanine bases in target DNA produce a large signal. Less than [Formula: see text] target amplicons can be detected on a microspot, approaching the sensitivity limit of conventional laser-based fluorescence techniques. This method also eliminates the labelling requirement and makes the measurements much simpler. This platform can be employed for developing highly automated electronic chips with multiplex nanoelectrode arrays for quick DNA analysis.

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