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1.
QJM ; 112(5): 327-333, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30629251

RESUMO

BACKGROUND: Osteoporosis is a global disease burden for aging society. The role of quantitative ultrasound (QUS) in the prediction for osteoporosis in a dose-response manner is hardly addressed. AIM: We aimed to show the dose-response of QUS measurement in the prediction for osteoporosis by a community-based study. DESIGN: A prospective cohort study. METHODS: Participants were recruited between 2000 and 2004. Demographic data and heel QUS measurement were collected at baseline. Diagnosis of osteoporosis was ascertained by the follow-up of this cohort over time. In order to reduce the imbalance of baseline characteristics in the observational study, we applied propensity score by using proportional odds regression analysis to match the quintiles of QUS T-score. RESULTS: A total of 44 957 subjects composed of 17 678 men (39.3%) and 27 279 women (69.7%) were recruited. After adjustments for propensity score, an increase in one unit of QUB T-score led to 7% reduction in the risk for osteoporosis [adjusted odds ratio (OR) = 0.93, 95% confidence interval (CI): 0.89-0.96, P < 0.0001]. Higher quintile of QUS T-score yielded a lower risk of osteoporosis with a gradient relationship [OR: 0.82 (95%CI: 0.72-0.92); OR: 0.81 (95%CI: 0.71-0.91); OR: 0.77 (95%CI: 0.68-0.87) and OR: 0.76 (95%CI: 0.67-0.86)] from the second to highest quintile opposed to first quintile (P < 0.0001). The cumulative incidence of osteoporosis was higher in the lower quintile during follow-up (log-rank test, P < 0.001). CONCLUSION: QUS is an independent predictor for osteoporosis in a dose-response manner using a large population-based cohort. Due to the lower cost and portability of QUS measurement, the pre-screening for osteoporosis by QUS can be considered in the area with limited resources can be a feasible and alternative method.


Assuntos
Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcâneo/diagnóstico por imagem , Densitometria , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Prospectivos , Taiwan/epidemiologia , Ultrassonografia
2.
Nanoscale ; 10(16): 7352-7356, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29637986

RESUMO

Here we aim to develop a facile emulsion-based method to prepare tripod gold nanoparticles (AuNPs) with high suspension stability in an aqueous environment. A gyroid-structured polymer template formed by the hydrolysis of a degradable block copolymer, polystyrene (PS)-b-poly(l-lactide), is used for the fabrication of AuNPs. Also, a successful emulsification of dichloromethane (DCM) in the aqueous phase is developed by using thiolated polyethylene glycol (PEG-SH) as the stabilizer. Subsequently, the nanohybrids of PS/Au can be fabricated by templated electroless plating, and then selectively dissolving in the DCM dispersive phase. Most interestingly, a dedicated process for the simultaneous release of the tripod AuNPs from the dissolution of PS associated with PEG-SH at the interface of the emulsion is achieved, giving PEG-SH-functionalized tripod AuNPs dispersed in the aqueous phase, which significantly improves the suspension stabilization of tripod AuNPs. The in situ temperature-programmed electrospray-differential mobility analysis provides a quantitative, statistical analysis of mobility diameter, dynamic shape factor, polydispersity, and colloidal stability.

3.
Epidemiol Psychiatr Sci ; 26(6): 624-634, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27435692

RESUMO

AIMS: Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan. METHOD: Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year. RESULTS: The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16). CONCLUSIONS: The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40-50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.


Assuntos
Inibidores da Captação Adrenérgica/uso terapêutico , Cloridrato de Atomoxetina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Metilfenidato/uso terapêutico , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Vigilância da População , Prevalência , Taiwan/epidemiologia
4.
Curr Top Membr ; 78: 513-59, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27586294

RESUMO

The cardiac Na(+) channel (Nav1.5) conducts a depolarizing inward Na(+) current that is responsible for the generation of the upstroke Phase 0 of the action potential. In heart tissue, changes in Na(+) currents can affect conduction velocity and impulse propagation. The cardiac Nav1.5 is also involved in determination of the action potential duration, since some channels may reopen during the plateau phase, generating a persistent or late inward current. Mutations of cardiac Nav1.5 can induce gain or loss of channel function because of an increased late current or a decrease of peak current, respectively. Gain-of-function mutations cause Long QT syndrome type 3 and possibly atrial fibrillation, while loss-of-function channel mutations are associated with a wider variety of phenotypes, such as Brugada syndrome, cardiac conduction disease, dilated cardiomyopathy, and sick sinus node syndrome. The penetrance and phenotypes resulting from Nav1.5 mutations also vary with age, gender, body temperature, circadian rhythm, and between regions of the heart. This phenotypic variability makes it difficult to correlate genotype-phenotype. We propose that mutations are only one contributor to the phenotype and additional modifications on Nav1.5 lead to the phenotypic variability. Possible modifiers include other genetic variations and alterations in the life cycle of Nav1.5 such as gene transcription, RNA processing, translation, posttranslational modifications, trafficking, complex assembly, and degradation. In this chapter, we summarize potential modifiers of cardiac Nav1.5 that could help explain the clinically observed phenotypic variability. Consideration of these modifiers could help improve genotype-phenotype correlations and lead to new therapeutic strategies.


Assuntos
Miócitos Cardíacos/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Potenciais de Ação , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/patologia , Genótipo , Humanos , Mutação , Canal de Sódio Disparado por Voltagem NAV1.5/química , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Fenótipo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Splicing de RNA , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
5.
Cell Mol Biol (Noisy-le-grand) ; 61(6): 85-91, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26518899

RESUMO

Hepatic steatosis has been reported to be a risk factor for the development of liver cancer. The underlying mechanism for carcinogenesis remains to be elucidated. It has been postulated that cancer stem cells (CSCs) within tumor tissues are a subset of cells with stem cell properties of self-renewal and undifferentiation. The purpose of this study was to investigate the effects of a saturated fatty acid, palmitate (PA), on CSC-like properties of human hepatoma HepG2 cells. We investigated the effects of PA on HepG2 cells and primary rat hepatocytes (PRH) by exposing them to PA to induce lipid accumulation. Significant fat accumulation was observed by Oil Red O staining in cells exposed to PA, and it was accompanied by significant increase in NFκB (p65) nuclear translocation in HepG2 cells. Notably, PA significantly enhanced the sphere forming ability of HepG2 cells, but not PRH. Furthermore, PA significantly increased stemness gene expressions of Sox2 and Oct4, and sonic hedgehog (Shh) production. Notably, NFκB inhibitors, N-Acetyl-L-cysteine and pyrollidine dithiocarbamate, and a NOX inhibitor, diphenyleneiodonium, significantly attenuated PA-induced sphere forming ability of HepG2 cells. Our results suggest that lipid accumulation may not only induce pro-inflammatory responses in hepatocytes but may also activate CSC-like properties of hepatoma cells through NFκB activation.


Assuntos
Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Palmitatos/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular , Células Cultivadas , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Inflamação/patologia , Neoplasias Hepáticas/patologia , Masculino , Células-Tronco Neoplásicas/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Ratos Wistar , Fator de Transcrição RelA/metabolismo
6.
Br J Cancer ; 112(1): 171-6, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25474251

RESUMO

BACKGROUND: We aim to report the prevalence of irritable bowel syndrome (IBS) and elucidate the influence of IBS on the incidence of colorectal neoplasm through a community-screening-based, longitudinal follow-up study. METHODS: We enroled 39,384 community residents aged 40 years or older who had participated in a community-based colorectal cancer-screening programme with an immunochemical faecal occult test since 1999. We followed a cohort that was free of colorectal neoplasm (excluding colorectal neoplasm at baseline) to ascertain the incident colorectal neoplasm through each round of screening and used a nationwide cancer registry. Information on IBS was obtained by linking this screened cohort with population-based health insurance claim data. Other confounding factors were also collected via questionnaire or biochemical tests. RESULTS: The overall period prevalence of IBS was 23%, increasing from 14.7% for subjects aged 40-49 years to 43.7% for those aged 70 years and more. After controlling for age, gender and family history of colorectal cancer, screenees who had been diagnosed as having IBS exhibited a significantly elevated level (21%; adjusted hazard ratio (HR)=1.21 (95% CI: 1.02-1.42)) of incident colorectal adenoma compared with those who had not been diagnosed with IBS. A similar finding was noted for invasive carcinoma; however, the size of the effect was of borderline statistical significance (adjusted HR=1.20 (95% CI: 0.94-1.53)). CONCLUSIONS: IBS led to an increased risk for incident colorectal neoplasm.


Assuntos
Neoplasias Colorretais/epidemiologia , Síndrome do Intestino Irritável/epidemiologia , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Taiwan/epidemiologia
8.
Transplant Proc ; 42(7): 2666-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20832566

RESUMO

BACKGROUND: The intramedullary cavity is a widely distributed well-vascularized microenvironment capable of sustaining grafts, and is a potential site for islet transplantation. The bone marrow offers sufficient space that may also be suitable for bioartificial pancreas (BAP) implantation. OBJECTIVE: To evaluate the feasibility of bone marrow as an implantation site for BAPs. MATERIALS AND METHODS: A calcium phosphate cement chamber satisfies the criteria for immunoisolation. Mouse insulinoma cells were suspended with agarose gel and enclosed in a calcium phosphate cement chamber to create a BAP, which was implanted in the intramuscular space in diabetic swine or the intramedullary cavity in diabetic dogs. Blood glucose and C-peptide concentrations were determined perioperatively. RESULTS: In the swine, the mean ± SD blood glucose concentration decreased from 413 ± 24 mg/dL to 285 ± 47 mg/dL, and was maintained in the range of 285 to 336 mg/dL for 15 days. It increased to 368 to 450 mg/dL after the BAPs were implanted in the intramuscular space. In the dogs, the blood glucose concentration decreased from 422 ± 32 mg/dL to 247 ± 52 mg/dL, and was maintained in the range of 247 to 347 mg/dL after the BAPs were implanted in the intramedullary cavity. The C-peptide concentration increased from 6.1 ± 2.8 pmol/L to 104.7 ± 16.4 pmol/L when the BAPs were implanted in the intramedullary cavity. CONCLUSION: This study indicates superior effectiveness of BAPs implanted in the intramedullary cavity compared with the intramuscular space. This observation may be attributed to the greater oxygen tension in the bone marrow. The BAPs in direct contact with the circulatory system receive sufficient blood flow for function and survival. This preliminary study demonstrates that the intramedullary cavity may be an implantation site for BAP transplantation.


Assuntos
Órgãos Bioartificiais/estatística & dados numéricos , Insulinoma/patologia , Medula Renal/cirurgia , Transplante de Pâncreas/métodos , Animais , Glicemia/metabolismo , Cimentos Ósseos , Medula Óssea/anatomia & histologia , Peptídeo C/sangue , Cães , Insulinoma/cirurgia , Camundongos , Próteses e Implantes/estatística & dados numéricos , Suínos
9.
Br J Dermatol ; 163(6): 1238-44, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20698845

RESUMO

BACKGROUND: Patients with tuberous sclerosis complex (TSC) develop fibrous tumours in the brain, skin, kidney, heart and lungs due to TSC1/2 mutations. In the skin, patients develop angiofibromas that have vascular and fibrotic components in which transforming growth factor (TGF)-ß and matrix metalloproteinase (MMP)-2 are important. OBJECTIVES: To investigate if the TGF-ß axis and MMP-2 play an important role in the pathogenesis of TSC angiofibromas. METHODS: Samples from TSC angiofibromas and normal skin were measured for expression of TGF-ß and MMP-2 by immunohistochemistry and real-time polymerase chain reaction. Fibroblasts grown from TSC angiofibromas (TSC fibroblasts) were incubated with TGF-ß. Expression of ERK, AKT and S6K was measured by Western blotting, and MMP-2 expression and activity were determined by enzyme-linked immunosorbent assay and gelatin zymography, respectively. RESULTS: There was an increase in the expression of TGF-ß and MMP-2 in TSC tumours compared with those in normal skin. The baseline expression of MMP-2 was increased in conditioned medium from TSC fibroblasts. In addition, TGF-ß enhanced MMP-2 production and activity, which could be abrogated by pretreatment with an AKT inhibitor (LY294002) but not with rapamycin. Finally, there was a significant colocalization of TGF-ß and MMP-2 in the TSC tumours. CONCLUSIONS: There is an increase of MMP-2 as a result of TGF-ß acting through AKT in TSC tumour cells. This regulation of the TGF-ß-AKT-MMP-2 axis is independent of mammalian target of rapamycin (mTOR) signalling. In addition to targeting the mTOR pathway, targeting TGF-ß simultaneously could block dysregulated tissue remodelling in TSC tumours.


Assuntos
Angiofibroma/enzimologia , Fibroblastos/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Esclerose Tuberosa/enzimologia , Angiofibroma/complicações , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Imuno-Histoquímica , Reação em Cadeia da Polimerase/métodos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Esclerose Tuberosa/complicações
10.
J Eur Acad Dermatol Venereol ; 23(8): 887-90, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19453795

RESUMO

BACKGROUND: Facial epidermoid cyst is a common benign epithelial tumour frequently seen in young or middle-aged people and may cause aesthetic disability. Surgical excision is the most frequently used method but may result in obvious scar. OBJECTIVE: To improve cosmetic result of removing facial epidermoid cyst through minimal incision surgery. METHODS: Twenty-two cases of facial epidermoid cysts ranging from 0.5 to 1.4 cm in diameter were treated. The skin above the epidermoid cysts was infiltrated with local 0.1-cc 1% xylocaine anaesthetic by using a 26-gauge needle first, then 3-mm incisions were made with a No.11 surgical blade. The cystic contents and its capsule were then squeezed out through the small incision and the underlying connective tissue was chemically cauterized by 20% trichloroacetic acid. The incision wounds were left unsutured. RESULT: Minimal incision method successfully treated 16 out of the 22 epidermoid cyst cases that ranged from 0.5 to 1 cm in diameter. And only one out of six was successfully treated for diameters greater than 1.1 cm. CONCLUSION: The proposed method can minimize the scar when treating facial epidermal inclusion cysts that are less than 1 cm and obtained better cosmetic results.


Assuntos
Cisto Epidérmico/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Dermatopatias/cirurgia , Adolescente , Adulto , Cicatriz/prevenção & controle , Face , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
11.
Transplant Proc ; 40(10): 3623-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19100454

RESUMO

PURPOSE: A chitosan/gelatin solution with glycerol 2-phosphate disodium salt hydrate in liquid phase at room temperature becomes a hydrogel at 37 degrees C. The material can be used as an injectable cell carrier into the human body for gelation in situ. We hoped that the chitosan/gelatin hydrogel provided extra protection for insulinoma/agarose microspheres during xenogenic transplantation. MATERIALS AND METHODS: Mouse insulinoma was microencapsulated in agarose as microspheres, which were macroencapsulated in chitosan/gelatin hydrogel. Insulin secreting profiles were first demonstrated in vitro. Diabetic rats were injected subcutaneously with insulinoma/agarose microspheres or insulinoma/agarose microspheres suspended in chitosan/gelatin solution. The nonfasting blood glucose concentrations (NFBG) of diabetic rats were measured perioperatively. Rats were humanely killed 1 month postoperatively and the hydrogel was retrieved for histological examination. RESULTS: The insulinoma/agarose microspheres continually secreted insulin for 1 month when macroencapsulated in chitosan/gelatin hydrogel in vitro. The NFBG of diabetic rats injected with insulinoma/agarose microspheres decreased to euglycemic status albeit hyperglycemia was restored within 10 days. The NFBG of diabetic rats injected with chitosan/gelatin hydrogel, which contained insulinoma/agarose microspheres, was maintained at less than 200 mg/dL for 25 days. The histological section revealed immune cell infiltration and accumulation within the hydrogel and around the iusulinoma/agarose microspheres that may have contributed to the slowly increasing NFBG after day 25. CONCLUSION: This study showed that chitosan/gelatin hydrogel can be used as a cell carrier for an injectable bioartificial pancreas; the hydrogel prolonged the function of cells encapsulated in agarose microspheres during xenogenic transplantation.


Assuntos
Gelatina/uso terapêutico , Hidrogéis/uso terapêutico , Insulinoma/patologia , Insulinoma/cirurgia , Transplante de Neoplasias/métodos , Animais , Quitosana/uso terapêutico , Insulina/metabolismo , Secreção de Insulina , Insulinoma/metabolismo , Camundongos , Transplante de Neoplasias/patologia , Ratos , Sefarose , Transplante Heterólogo
13.
Phys Rev Lett ; 84(21): 4806-9, 2000 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-10990803

RESUMO

The newly observed &Bmacr;( 0)-->&Kmacr;( 0)pi(0) mode is quite sizable while pi(-)pi(+) is rather small. Data also hint at pi(-)pi(0) greater, similarpi(-)pi(+). Though consistent with zero, central values of CP violating asymmetries in K-pi(+,0) and &Kmacr;( 0)pi(-) show an interesting pattern. Taking cue from these, we suggest that, besides gamma identical witharg(V(*)(ub)) being large, the rescattering phase delta in Kpi and pipi modes may be greater than 90 degrees. If this is true, not only the above trends can be accounted for, but one would also find pi(0)pi(0) approximately pi(-)pi(+,0), and the CP asymmetry in &Bmacr;( 0) vs B0-->pi(-)pi(+) could be as large as -60%. These results can be tested in a couple of years.

14.
Phys Rev D Part Fields ; 49(11): 6247-6248, 1994 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10021663
15.
Phys Rev D Part Fields ; 49(1): 460-465, 1994 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10016783
16.
Phys Rev D Part Fields ; 47(7): 3001-3012, 1993 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10015904
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