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1.
Int J Med Sci ; 18(15): 3470-3477, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522173

RESUMO

Background: The aim of this study was to investigate the associations among obesity-related indices and MetS in diabetic patients, and explore sex differences in these associations. Methods: Patients with type 2 DM were included from two hospitals in southern Taiwan. The Adult Treatment Panel III criteria for an Asian population were used to define MetS. In addition, the following obesity-related indices were evaluated: waist-to-height ratio, waist-hip ratio (WHR), conicity index (CI), body mass index (BMI), body roundness index, body adiposity index, lipid accumulation product (LAP), abdominal volume index, visceral adiposity index (VAI), abdominal volume index and triglyceride-glucose index. Results: A total of 1,872 patients with type 2 DM (mean age 64.0 ± 11.3 years, 808 males and 1,064 females) were enrolled. The prevalence rates of MetS were 59.8% and 76.4% in the males and female (p < 0.001), respectively. All of the obesity-related indices were associated with MetS in both sex (all p < 0.001). LAP and BMI had the greatest areas under the receiver operating characteristic curves in both sex. In addition, the interactions between BMI and sex (p = 0.036), WHR and sex (p = 0.016), and CI and sex (p = 0.026) on MetS were statistically significant. Conclusions: In conclusion, this study demonstrated significant relationships between obesity-related indices and MetS among patients with type 2 DM. LAP and VAI were powerful predictors in both sex. The associations of BMI, WHR and CI on MetS were more significant in the men than in the women.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Indicadores Básicos de Saúde , Síndrome Metabólica/fisiopatologia , Obesidade/fisiopatologia , Fatores Sexuais , Adiposidade , Idoso , Antropometria , Glicemia/análise , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/complicações , Taiwan , Triglicerídeos/sangue , Razão Cintura-Estatura , Relação Cintura-Quadril
2.
Nat Mater ; 15(8): 876-81, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27322822

RESUMO

TiAl alloys are lightweight, show decent corrosion resistance and have good mechanical properties at elevated temperatures, making them appealing for high-temperature applications. However, polysynthetic twinned TiAl single crystals fabricated by crystal-seeding methods face substantial challenges, and their service temperatures cannot be raised further. Here we report that Ti-45Al-8Nb single crystals with controlled lamellar orientations can be fabricated by directional solidification without the use of complex seeding methods. Samples with 0° lamellar orientation exhibit an average room temperature tensile ductility of 6.9% and a yield strength of 708 MPa, with a failure strength of 978 MPa due to the formation of extensive nanotwins during plastic deformation. At 900 °C yield strength remains high at 637 MPa, with 8.1% ductility and superior creep resistance. Thus, this TiAl single-crystal alloy could provide expanded opportunities for higher-temperature applications, such as in aeronautics and aerospace.

3.
Kaohsiung J Med Sci ; 40(4): 384-394, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38332510

RESUMO

Transcatheter aortic valve replacement (TAVR) is a well-established procedure using a catheter-introduced valve prosthesis for patients with severe aortic stenosis (AS). This retrospective study investigated sex-related differences in pre- and post-TAVR clinical and hemodynamic outcomes and analyzed data of the first 100 cases at Kaohsiung Medical University Chung-Ho Memorial Hospital (KMUH) between December 2013 and December 2021. Baseline characteristics, procedural outcomes, mortality rates, and echocardiographic parameters were analyzed and compared between sexes. Among the 100 patients, male (46%) and female (54%) were of similar age (mean age, male 86.0 years vs. female 84.5 years) and of the same severity of AS (mean pressure gradient, male 47.5 mmHg vs. female 45.7 mmHg) at the time receiving the TAVR procedure. Women had smaller aortic valve areas calculated by continuity equation (0.8 ± 0.3 cm2 vs. 0.7 ± 0.2 cm2, p < 0.001). In addition, women had better left ventricle ejection fraction (59.6 ± 14.0% vs. men 54.7 ± 17.2%, p < 0.01). In the post-TAVR follow-up, regression of left ventricle mass and dimension was better in women than in men. None of the patient died within 30 days after the procedure, and women tended to have a more favorable survival than men (2-year mortality and overall mortality rate in 8.3 year, women 9.1% and 22.2% vs. men 22.2% and 34.8%; p = 0.6385 and 0.1277, respectively). In conclusion, the sex-based difference in post-TAVR regression of LV remodeling suggests a need for sex-based evaluation for patients with severe AS and their post TAVR follow-up.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Masculino , Feminino , Idoso de 80 Anos ou mais , Substituição da Valva Aórtica Transcateter/métodos , Seguimentos , Estudos Retrospectivos , Estenose da Valva Aórtica/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Resultado do Tratamento , Hipertrofia/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Índice de Gravidade de Doença
4.
Materials (Basel) ; 16(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37512440

RESUMO

The present study investigates the creep behavior and deformation mechanism of a third-generation single-crystal Ni-based superalloy at 1170 °C under a range of stress levels. Scanning electron microscopes (SEM) and transmission electron microscopes (TEM) were employed to observe the formation of a rafted γ' phase, which exhibits a topologically close-packed (TCP) structure. The orientation relationship and elemental composition of the TCP phase and matrix were analyzed to discern their impact on the creep properties of the alloy. The primary deformation mechanism of the examined alloy was identified as dislocation slipping within the γ matrix, accompanied by the climbing of dislocations over the rafted γ' phase during the initial stage of creep. In the later stages of creep, super-dislocations with Burgers vectors of a<010> and a/2<110> were observed to shear into the γ' phase, originating from interfacial dislocation networks. Up to the fracture, the sequential activation of dislocation shearing in the primary and secondary slipping systems of the γ' phase occurs. As a consequence of this alternating dislocation shearing, a twist deformation of the rafted γ' phase ensued, ultimately contributing to the fracture mechanism observed in the alloy during creep.

5.
Biotechnol Bioeng ; 109(10): 2460-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22511236

RESUMO

In this article, a technique for accurate direct measurement of protein-to-protein interactions before and after the introduction of a drug candidate is developed using atomic force microscopy (AFM). The method is applied to known immunosuppressant drug candidate Echinacea purpurea derived cynarin. T-cell/CD28 is on-chip immobilized and B-cell/CD80 is immobilized on an AFM tip. The difference in unbinding force between these two proteins before and after the introduction of cynarin is measured. The method is described in detail including determination of the loading rates, maximum probability of bindings, and average unbinding forces. At an AFM loading rate of 1.44 × 10(4) pN/s, binding events were largely reduced from 61 ± 5% to 47 ± 6% after cynarin introduction. Similarly, maximum probability of bindings reduced from 70% to 35% with a blocking effect of about 35% for a fixed contact time of 0.5 s or greater. Furthermore, average unbinding forces were reduced from 61.4 to 38.9 pN with a blocking effect of ≈ 37% as compared with ≈ 9% by SPR. AFM, which can provide accurate quantitative measures, is shown to be a good method for drug screening. The method could be applied to a wider variety of drug candidates with advances in bio-chip technology and a more comprehensive AFM database of protein-to-protein interactions.


Assuntos
Microscopia de Força Atômica/métodos , Mapeamento de Interação de Proteínas/métodos , Proteínas/metabolismo , Antígeno B7-1/metabolismo , Antígenos CD28/metabolismo , Cinamatos/metabolismo , Ligação Proteica
6.
Nutrients ; 12(6)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32516885

RESUMO

BACKGROUND: Osteoporosis is highly prevalent in postmenopausal women and may result in fractures and disabilities. Total thyroidectomy has also been associated with loss of bone mass. The aim of this cross-sectional study was to evaluate associations among nutritional status, skeletal muscle index and markers of bone turnover to bone mineral density in postmenopausal women who had undergone total thyroidectomy. METHODS: Fifty postmenopausal women who had undergone total thyroidectomy were included. Body composition was measured using dual-energy X-ray absorptiometry (DXA). The Geriatric Nutritional Risk Index (GNRI) was calculated using baseline body weight and serum albumin level. Skeletal muscle mass index was calculated as the appendicular skeletal muscle mass (ASM) divided by the height squared and assessed using DXA. RESULTS: Multivariate stepwise linear regression analysis showed that a low GNRI was significantly associated with low lumbar spine bone mineral density (BMD) and T-score, and that a low ASM/height2 was significantly associated with low femoral neck BMD and T-score. A low vitamin D level was significantly associated with low femoral neck BMD and T-score and low total hip BMD and T-score. A high bone alkaline phosphatase (ALP) level was significantly associated with low femoral neck T-score and low total hip BMD and T-score. A low insulin-like growth factor-1 (IGF-1) was significantly associated with low total hip BMD and T-score. CONCLUSION: In the postmenopausal women who had undergone total thyroidectomy in this study, BMD was positively associated with GNRI, skeletal muscle mass index, and levels of vitamin D and serum IGF-1, and inversely associated with bone ALP level. Nutritional status, skeletal muscle mass index and bone turnover biomarkers can be used to early identify patients with a high risk of osteoporosis in this high-risk group.


Assuntos
Constituição Corporal , Densidade Óssea , Avaliação Geriátrica , Músculo Esquelético/metabolismo , Avaliação Nutricional , Fenômenos Fisiológicos da Nutrição/fisiologia , Estado Nutricional , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/metabolismo , Pós-Menopausa , Tireoidectomia/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/fisiologia , Composição Corporal , Estudos Transversais , Feminino , Colo do Fêmur/metabolismo , Humanos , Vértebras Lombares/metabolismo , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/prevenção & controle , Risco
7.
Polymers (Basel) ; 11(5)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052601

RESUMO

Two new dicarboxylate-based three-dimensional cobalt coordination polymers, [Co(Me2mal)(bpe)0.5(H2O)]n (1) and [Co(Me2mal)(bpe)0.5]n (2), were synthesized from dimethylmalonic acid (H2-Me2mal) in temperature-controlled solvothermal reactions. Lower temperatures (6080 °C) favored the formation of 1, while higher temperatures (120 °C) favored the production of 2. Compound 1 is comprised of Co(II) corrugated layers linked by syn-anti carboxylate bridges from the Me2mal2- ligands and pillared through bis-monodentate bpe groups. Compound 2 is comprised of a three-dimensional network involving one-dimensional Co-carboxylate chains bonded by antisymmetric µ4-Me2mal2- ligands and aligned parallel to the [001] direction. The solvothermal retreatment of crystalline samples of 1 in a DMF/H2O solvent at 120 °C allowed the structural reassembly, with complete conversion within 2 over 48 h. Magnetic analyses revealed that compound 1 exhibits both spin-orbital coupling and antiferromagnetic interactions through a syn-anti carboxylate (Me2mal2-) bridge exchange pathway [Co-Co separation of 5.478 Å] and compound 2 showed a ferromagnetic interaction resulting from the short Co-Co separation (3.150 Å) and the small Co-O-Co bridging angles (98.5° and 95.3°) exchange pathway which was provided by µ4-Me2mal2- bridging ligand.

8.
Peptides ; 30(5): 839-48, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19428759

RESUMO

Several natural antimicrobial peptides including cecropins, magainins and melittins have been found to kill cancer cells. However, their efficacy may not be adequate for their development as anticancer agents. In this study, we used a natural antimicrobial peptide, cecropin B (CB), as a template to generate a novel anticancer peptide. Cecropin B is an amphipathic and polycationic peptide derived from the hemolymph of Hyalophora cecropia with well-known antimicrobial and cytolytic properties. The signature pattern of cecropins is W-x-(0,2)-[KDN]-x-{L}-K-[KRE]-[LI]-E-[RKN] (PROSITE: PS00268), and this signature sequence is located at N-terminus of CB. CB1a was constructed by repeating the N-terminal ten amino acids of CB three times and including a hinge near C-terminus. The circular dichroism spectra showed that CB1a is unstructured in aqueous solution, but adopt a helical conformation in membrane-like environment. The solution structure of CB1a in a polar solvent was also studied by NMR. CB1a formed a helix-hinge-helix in 20% HFIP solution, and it was found the bent angle between two helical segments was induced ranging from 60 degrees to 110 degrees . A heparin-binding motif is located in the central part of helix 1. Isothermal titration calorimetry reveals the association constant of CB1a bound to low molecular weight heparin is 1.66 x 10(5)M(-1) at physiological ionic strength at 25 degrees C. Binding of CB1a to heparin produces a large conformational change toward a more structural state. CB1a demonstrated promising activity against several cancer cells but low toxicity against non-cancer cells. The IC(50) of CB1a on leukemia and stomach carcinoma cells were in the range of 2-8-fold lower than those of CB. Besides, CB1a exhibited low hemolytic activity against human red blood cells. Due to these properties, CB1a has the potential to become a promising anticancer agent.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proteínas de Insetos/química , Proteínas de Insetos/farmacologia , Sequência de Aminoácidos , Animais , Calorimetria , Linhagem Celular , Linhagem Celular Tumoral , Dicroísmo Circular , Citometria de Fluxo , Hemólise/efeitos dos fármacos , Humanos , Microscopia Confocal , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Estrutura Secundária de Proteína , Relação Estrutura-Atividade
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