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1.
Heliyon ; 10(7): e28090, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38571596

RESUMEN

Background: Lung adenocarcinoma (LUAD) has a complex tumor heterogeneity. Our research attempts to clearness LUAD subtypes and build a reliable prognostic signature according to the activity changes of the hallmark and immunologic gene sets. Methods: According to The Cancer Genome Atlas (TCGA) - LUAD dataset, changes in marker and immune gene activity were analyzed, followed by identification of prognosis-related differential gene sets (DGSs) and their related LUAD subtypes. Survival analysis, correlation with clinical characteristics, and immune microenvironment assessment for subtypes were performed. Moreover, the differentially expressed genes (DEGs) between different subtypes were identified, followed by the construction of a prognostic risk score (RS) model and nomogram model. The tumor mutation burden (TMB) and tumor immune dysfunction and exclusion (TIDE) of different risk groups were compared. Results: Two LUAD subtypes were determined according to the activity changes of the hallmark and immunologic gene sets. Cluster 2 had worse prognosis, more advanced tumor and clinical stages than cluster 1. Moreover, a prognostic RS signature was established using two LUAD subtype-related DEGs, which could stratify patients at different risk levels. Nomogram model incorporated RS and clinical stage exerted good prognostic performance in LUAD patients. A shorter survival time and higher TMB were observed in the high-risk patients. Conclusions: Our findings revealed that our constructed prognostic signature could exactly predict the survival status of LUAD cases, which was helpful in predicting the prognosis and guiding personalized therapeutic strategies for LUAD.

2.
Huan Jing Ke Xue ; 43(4): 2071-2080, 2022 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-35393831

RESUMEN

The concentrations of rare earth elements (REEs) in protected vegetable soils in Wuqing district of Tianjin City, Jinzhong district of Shanxi Province, Shenyang district of Liaoning Province, and Wulanchabu district of Inner Mongolia Autonomous Region in northern China were measured to analyze the change characteristics of soil REEs in the process of protected vegetable cultivation. Additionally, we sought to use the REEs parameters to trace the feasibility of characterizing the interference of human activities on the soil ecological environment. The results showed that the total content of REEs (REE) in the topsoil of protected vegetable fields ranged from 146.52 to 158.76 mg·kg-1, with an average of 152.34 mg·kg-1 in Shenyang; 92.16 to 137.69 mg·kg-1, with an average of 115.03 mg·kg-1in Wuqing; 91.38 to 118.84 mg·kg-1, with an average of 108.03 mg·kg-1 in Wulanchabu; and 97.62 to 111.27 mg·kg-1, with an average of 102.43 mg·kg-1in Jinzhong. The REEs distribution patterns in the soils of the four areas, standardized with chondrite, characterized by a right tilt, showed that light rare earth elements were obviously enriched in the soil, demonstrated by the ratios of LREE/HREE and (La/Yb) N, which were greater than 6 and 7, respectively. The values of (La/Sm)N in the soils were higher than 3, suggesting that there was an obvious fractionation between light rare earth elements, whereas the values of (Gd/Yb)N were between 1-2, and there was a weak fractionation between heavy rare earth elements. The values of δEu in the soils were between 0.56 and 0.61, showing that Eu had a negative abnormality. The values of δCe were between 0.89 and 1.11, showing that Ce had no abnormality or weak positive abnormality. The higher LREE/HREE and (La/Yb)N in protected vegetable soil than that in open-air vegetable soil indicated the increasing differentiation degree between light and heavy rare earth elements in protected vegetable soil. The lower (La/Sm)N in protected vegetable soils indicated the reduction in the differentiation among light rare earth elements in soil. Higher δCe values and lower δEu values suggested that Ce and Eu were relatively enriched and depleted, respectively, during vegetable planting. The REE, LREE, (La/Sm)N, and δEu in protective soil decreased with the number of cultivation years, whereas the (Gd/Yb)N and δCe increased, but the HREE values did not change significantly. There was a significant correlation between δCe, δEu, (La/Yb)N, (Gd/Yb)N, and soil bulk density, soil moisture content, and soil organic matter in Tianjin protected vegetable soils, showing preliminarily that rare earth elements can be used as tracer elements to characterize the interference intensity of human activities on soil.


Asunto(s)
Metales de Tierras Raras , Contaminantes del Suelo , China , Humanos , Metales de Tierras Raras/análisis , Suelo , Contaminantes del Suelo/análisis , Verduras
3.
Health Econ ; 30(4): 858-875, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33556215

RESUMEN

Recent reports show that at least 95% of the world's population is breathing polluted air. However, the impact of air quality on air pollution-related medical expenditure and utilization is sparse. This study estimates the short-term health care cost impacts of air pollution using a meteorological phenomenon-thermal inversion-as an instrumental variable for air quality. Using information on outpatient care for respiratory diseases from universal health insurance claim data in Taiwan during 2006-2012, our estimates suggest that a one-unit reduction in the air quality index (AQI) leads to NT$2.3 billion (nearly US$74 million) of savings in respiratory-related outpatient expenditure per year. Given that the average AQI is equal to 32 during our study period, completely removing air pollution would reduce the national health expenditure by approximately 8% annually. Our results provide the important implication that the cost of controlling air pollutant emissions can be offset by curtailing health care expenditure.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/estadística & datos numéricos , Gastos en Salud , Humanos , Material Particulado/análisis , Material Particulado/toxicidad , Taiwán/epidemiología
4.
Int Health ; 12(4): 272-280, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31647555

RESUMEN

BACKGROUND: This study empirically estimates the magnitude and associated determinants of profit margins that medical providers earn from prescription drugs based on Taiwan's pharmaceutical market. METHODS: Our main data set is from the population-based claims data compiled by the National Health Insurance Research Database covering three waves of price adjustment: July-December 2004, October 2007-September 2008 and October 2009-September 2010. Only drugs whose reimbursement prices were adjusted using the R-zone formula were used as samples for this study. By calculating the difference between retail and wholesale prices for 796 pharmaceutical products, we can estimate the profit margin determinants using the regression model. RESULTS: We found evidence that suppliers of generic drugs tend to offer larger discounts to medical providers than suppliers of brand-name drugs. In addition, the countervailing power of wholesale pharmaceuticals, as measured by the discount rate offered by pharmaceutical manufacturers, is positively associated with the degree of competition within the pharmaceutical market and the size of the market itself. CONCLUSIONS: Our findings imply that the profit-seeking behaviour exhibited by medical providers is the engine of competitive forces in Taiwan's prescription drug market. This creates financial incentives for them, which in turn influences their choices of prescription drugs.


Asunto(s)
Costos de los Medicamentos/estadística & datos numéricos , Medicamentos Genéricos/economía , Pautas de la Práctica en Medicina/economía , Medicamentos bajo Prescripción/economía , Industria Farmacéutica/economía , Medicamentos Genéricos/provisión & distribución , Humanos , Programas Nacionales de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Medicamentos bajo Prescripción/provisión & distribución , Taiwán
5.
Value Health Reg Issues ; 21: 120-126, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31704489

RESUMEN

OBJECTIVES: As populations are growing older, the prevalence of chronic diseases such as diabetes mellitus is rapidly increasing. Meanwhile, many new drugs are introduced each year as a result of technological advances. This study uses diabetes as an example to investigate the relative importance of population aging and technological innovation in accounting for the growth of health expenditures. METHODS: The retrospective cohort study was conducted based on claims data covering 1997 to 2006 taken from Taiwan's National Health Insurance. Patients were selected based on whether they received antidiabetic drugs. Growth in health expenditure was decomposed into 3 parts: number of patients, mean treatment cost, and the interaction between the change in the mean treatment cost and the change in the number of patients. RESULTS: The results indicated that 75% of the growth in expenditures for treating diabetic patients is attributable to the effect of population aging, as reflected by the increase in the diabetes prevalence rate (45%) and disease severity (30%). Technological innovation, in the form of treatment substitution (10%) and treatment expansion effects (15%), accounted for only about 25% of the growth in expenditures for treating diabetic patients. CONCLUSIONS: Population aging plays a more significant role than technological innovation in driving up health expenditures for the treatment of diabetic patients. This suggests that population aging may contribute significantly to the future growth of the healthcare sector in Asian countries such as Taiwan.


Asunto(s)
Envejecimiento/fisiología , Diabetes Mellitus Tipo 2/terapia , Gastos en Salud/normas , Invenciones/tendencias , Adulto , Envejecimiento/efectos de los fármacos , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Costos de la Atención en Salud/tendencias , Gastos en Salud/estadística & datos numéricos , Humanos , Invenciones/normas , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Taiwán
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 527-532, 2019 Jul.
Artículo en Chino | MEDLINE | ID: mdl-31642230

RESUMEN

OBJECTIVE: To investigate the effect of 2-deoxy-d-glucose (2-DG) combined with hydroxycamptothecin (HCPT) on anti-tumor activity of breast cancer cells and its mechanism. METHODS: MDA-MB-231 and MCF-7 breast cancer cells were incubated with varying concentrations of 2-DG (0, 1.25, 2.5, 5, 10, 20 mmol/L), HCPT(0, 5, 10, 20, 40 µmol/L) and 2-DG (5 mmol/L) combined with HCPT. Cell viability was measured using the MTT assay; Propidium iodide (PI) detected the apoptosis of MDA-MB-231 cells by 5 mmol/L 2-DG, 10 µmol/L HCPT alone or in combination; MDA-MB-231 cells were treated with 2-DG (0, 2.5, 5, 10, 20 mmol/L) and the level of ATP was detected by ATP kit; the expression of Akt, p-Akt, Bcl-2/Bax, PARP, Caspase-8 and Caspase-3 proteins in MDA-MB-231 cells were measured by Western blot assay. RESULTS: The combination of 2-DG (5 mmol/L) and HCPT had a synergistic effect. The 48 h combination index (CI < 1) was higher than that of the single-use group (P < 0.05). At the same time, the combination of the two drugs inhibits the phosphorylation of Akt protein and increases the activation of Caspase-3 protein, thereby increasing the cleavage of PARP proteins. CONCLUSION: The combination of 2-DG and HCPT can synergistically induce the apoptosis of breast cancer cells, which may be caused by inhibiting the energy generation of tumor cells, inhibiting the phosphorylation of Akt protein and enhancing the activity of caspase-3 protein.


Asunto(s)
Apoptosis , Neoplasias de la Mama/patología , Camptotecina/análogos & derivados , Desoxiglucosa/farmacología , Camptotecina/farmacología , Línea Celular Tumoral , Sinergismo Farmacológico , Humanos , Células MCF-7
7.
Cell Physiol Biochem ; 51(5): 2030-2040, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30522103

RESUMEN

BACKGROUND/AIMS: Preeclampsia (PE) is a gestational disorder defined as hypertension and proteinuria, which is deemed a major cause of maternal and neonatal mortality and morbidity worldwide. The aim of this study was to investigate the expression patterns of placental laminin (LN)-α5 expression in normal and PE pregnancies, as well as evaluating the effects of LN-α5 on trophoblast proliferation, apoptosis, and invasion. METHODS: LN-α5 expression levels were examined by reverse-transcriptase polymerase chain reaction (RT-PCR), and further confirmed by western blotting and immunofluorescence staining. Cell proliferation and apoptosis were measured by CCK-8 assay and flow cytometry. Cell invasion was assessed by matrigel-based transwell assay. LN-α5 DNA methylation in placentas was determined by bisulfite sequencing PCR (BSP). RESULTS: LN-α5 expression levels in PE placentas were significantly lower than that of normal pregnancies. Deficiency in LN-α5 expression resulted in decreased trophoblast proliferation and invasion but increased cell apoptosis, meanwhile, PI3K/AKT/mTOR signaling pathway was impaired by LN-α5 silencing. LN-α5 promoter methylation didn't show significant difference between PE and normal placentas. CONCLUSION: LN-α5 downregulation is associated with PE placenta and impairs trophoblast viability and invasiveness, which could be a causative factor of PE pathogenesis.


Asunto(s)
Regulación hacia Abajo , Laminina/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Preeclampsia/genética , Transducción de Señal , Trofoblastos/patología , Adulto , Apoptosis , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Metilación de ADN , Femenino , Humanos , Preeclampsia/metabolismo , Preeclampsia/patología , Embarazo , Trofoblastos/citología , Trofoblastos/metabolismo
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(5): 700-705, 2018 Sep.
Artículo en Chino | MEDLINE | ID: mdl-30378329

RESUMEN

OBJECTIVE: To investigate the role of SRC kinase inhibitor PP2 in drug resistance to adriamycin (ADM) in breast cancer cells and invasion, metastasis of cells. METHODS: MTT assay was used to detect the inhibitory effect of ADM on MCF-7 and MCF-7/ADM cells. The 50% inhibitory concentration (IC50) and resistance index (RI) of cells were calculated. The expression of MDR1, connexin 43 (Cx43) and SRC proteins in breast cancer cells were detected by Western blot assay. Transwell experiment and cell scratch test were used to determine the invasion and migration of cells respectively [MCF-7, MCF-7/ADM, PP2 (1, 2, 4 µmol/L)]. Standard colony formation assay was used to detect the cytotoxicity effect of 4 µmol/L PP2 pretreatment on ADM. RESULTS: ADM inhibited the proliferation of MCF-7 more than MCF-7/ADM cells (P<0.01). The IC50 of MCF-7/ADM cells was 24.55 µmol/L, the IC50 of MCF-7/ADM cells was 770.57 µmol/L, the RI was 31. Compared with MCF-7 cells, expressions of the multidrug resistance proteins MDR1 and SRC were significantly increased (P<0.01). The invasion and migration ability of the MCF-7/ADM cells was stronger than that of the sensitive cells (P<0.01). When MCF-7/ADM was exposed to SRC inhibitor PP2, the invasion and metastasis ability of cells were inhibited (P<0.01) and the rate of colony formation was decreased, that is, more sensitivity to ADM (P<0.01). CONCLUSION: The resistance of MCF-7 to ADM is accompanied by increased expression of SRC. SRC inhibitor PP2 can reduce the cell resistance, ability of invasion and metastasis.


Asunto(s)
Neoplasias de la Mama/enzimología , Doxorrubicina/metabolismo , Resistencia a Antineoplásicos , Pirimidinas/farmacología , Familia-src Quinasas/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Conexina 43/metabolismo , Humanos , Células MCF-7 , Invasividad Neoplásica , Metástasis de la Neoplasia
9.
J Nurs Manag ; 25(2): 85-92, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27885747

RESUMEN

AIM: To investigate the relationship between nursing hours per patient day and the inpatient mortality rate in Taiwan. BACKGROUND: Nursing hours per patient day has been associated with better patient outcomes. The literature is inconclusive on the relationship between nursing hours per patient day and the inpatient mortality rate, and no studies have yet examined this issue in Taiwan. METHODS: A retrospective longitudinal study analysed data from the 'Nursing Utilization of Resources, Staffing and Environment on Outcome Study: NURSE-outcome study'. Hierarchical regression estimated the relationship between nursing hours per patient day and in-hospital mortality rate after controlling for confounding variables. RESULTS: The mean nursing hours per patient day in Taiwan was 2.3, while the mean inpatient mortality rate was 0.73% higher nursing hours per patient day was associated with a lower inpatient mortality rate after controlling for confounding variables. The total explained variance of this study in inpatient mortality rate was 19.9%. Significant relationships to inpatient mortality were found in levels of hospitals, seasonal variation and nurses' work experience. CONCLUSION: Nursing hours per patient day affects the mortality rate among hospitalised patients in Taiwan. IMPLICATIONS FOR NURSING MANAGEMENT: According to the results, we suggested the government and managers in Taiwan double the nursing hours per patient day so that the inpatient mortality rate will decline by 1.1%. This might be the optimal nurse configuration that could provide a balance between cost-effectiveness and patient safety.


Asunto(s)
Mortalidad Hospitalaria , Personal de Enfermería en Hospital/provisión & distribución , Evaluación del Resultado de la Atención al Paciente , Admisión y Programación de Personal/normas , Humanos , Estudios Longitudinales , Personal de Enfermería en Hospital/economía , Personal de Enfermería en Hospital/estadística & datos numéricos , Seguridad del Paciente/estadística & datos numéricos , Admisión y Programación de Personal/economía , Admisión y Programación de Personal/estadística & datos numéricos , Estudios Retrospectivos , Taiwán
10.
J Diabetes ; 9(3): 256-266, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27062145

RESUMEN

BACKGROUND: Studies from other countries indicate that utilization patterns of antidiabetic drugs change significantly after the introduction of newer classes of antidiabetic drugs (e.g. dipeptidyl peptidase-4 inhibitors [DPP-4i]). Evidence on recent trends regarding antidiabetic drug use in Taiwan is lacking, especially for times after the introduction of newer classes of drugs (e.g. DPP-4i). Therefore, the aim of the present study was to assess: (i) recent trends in the use and spending on antidiabetic drugs; (ii) changes in utilization patterns after introduction of newer classes of antidiabetic drugs; and (iii) factors associated with the choice of newer versus older classes of antidiabetic drugs. METHODS: Cases of type 2 diabetes were derived from Taiwan's National Health Insurance Research Database. Antidiabetic drug use was measured in terms of total quantity of drug exposure and healthcare spending in each calendar year from 2008 to 2103. Multiple logistic regression analysis was used to assess factors associated with drug choice. RESULTS: The use of and healthcare spending on DPP-4i increased significantly from 2008 to 2013, whereas healthcare spending on sulfonylureas decreased. For monotherapy, sulfonylureas were the most common alternatives to metformin, whereas in dual and triple antidiabetic therapies, a DPP-4i was the most common alternative to initial regimens. The use of a DPP-4i was positively associated with the use of beta-blockers, angiotensin II-converting enzyme inhibitors and/or angiotensin receptor blockers, and lipid-lowering agents, but negatively correlated with age, hypertension, severity of diabetes complications, and the use of diuretics and calcium channel blockers. CONCLUSIONS: With growing spending on newer antidiabetic drugs, future research on the comparative cost-effectiveness and safety of antidiabetic drugs is anticipated.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Quimioterapia/estadística & datos numéricos , Quimioterapia/tendencias , Hipoglucemiantes/uso terapéutico , Pueblo Asiatico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/etnología , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Humanos , Metformina/uso terapéutico , Vigilancia de la Población/métodos , Compuestos de Sulfonilurea/uso terapéutico , Taiwán
11.
Diabetes Res Clin Pract ; 116: 14-25, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27321311

RESUMEN

OBJECTIVE: To assess the cost-effectiveness of metformin-based dual therapies associated with cardiovascular disease (CVD) risk in a Chinese population with type 2 diabetes. METHODS: We utilized Taiwan's National Health Insurance Research Database (NHIRD) 1997-2011, which is derived from the claims of National Health Insurance, a mandatory-enrollment single-payer system that covers over 99% of Taiwan's population. Four metformin-based dual therapy cohorts were used, namely a reference group of metformin plus sulfonylureas (Metformin-SU) and metformin plus acarbose, metformin plus thiazolidinediones (Metformin-TZD), and metformin plus glinides (Metformin-glinides). Using propensity scores, each subject in a comparison cohort was 1:1 matched to a referent. The effectiveness outcome was CVD risk. Only direct medical costs were included. The Markov chain model was applied to project lifetime outcomes, discounted at 3% per annum. The bootstrapping technique was performed to assess uncertainty in analysis. RESULTS: Metformin-glinides was most cost-effective in the base-case analysis; Metformin-glinides saved $194 USD for one percentage point of reduction in CVD risk, as compared to Metformin-SU. However, for the elderly or those with severe diabetic complications, Metformin-TZD, especially pioglitazone, was more suitable; as compared to Metformin-SU, Metformin-TZD saved $840.1 USD per percentage point of reduction in CVD risk. Among TZDs, Metformin-pioglitazone saved $1831.5 USD per percentage point of associated CVD risk reduction, as compared to Metformin-rosiglitazone. CONCLUSIONS: When CVD is considered an important clinical outcome, Metformin-pioglitazone is cost-effective, in particular for the elderly and those with severe diabetic complications.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Complicaciones de la Diabetes/epidemiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Compuestos de Sulfonilurea/uso terapéutico , Tiazolidinedionas/uso terapéutico , Acarbosa/economía , Acarbosa/uso terapéutico , Anciano , Enfermedades Cardiovasculares/economía , Análisis Costo-Beneficio , Complicaciones de la Diabetes/economía , Diabetes Mellitus Tipo 2/economía , Quimioterapia Combinada , Femenino , Humanos , Hipoglucemiantes/economía , Masculino , Cadenas de Markov , Metformina/economía , Persona de Mediana Edad , Pioglitazona , Riesgo , Rosiglitazona , Compuestos de Sulfonilurea/economía , Taiwán/epidemiología , Tiazolidinedionas/economía
12.
ChemistryOpen ; 4(4): 478-82, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26478843

RESUMEN

Stimuli-responsive luminescent materials, which are dependent on changes in physical molecular packing modes, have attracted more and more interest over the past ten years. In this study, 2,2-dihydroxy-1,1-naphthalazine was synthesized and shown to exhibit different fluorescence emission in solution and solid states with characteristic aggregation-induced emission (AIE) properties. A remarkable change in the fluorescence of 2,2-dihydroxy-1,1-naphthalazine occurred upon mechanical grinding, heating, or exposure to solvents. According to the characterization by solid-state fluorescence spectroscopy, X-ray crystallography, differential scanning calorimetry, and X-ray powder diffraction, the fluorescence change could be attributed to transitions between two structurally different polymorphs. These significant properties could also give 2,2-dihydroxy-1,1-naphthalazine more potential applications as a multifunctional material.

13.
Inorg Chem ; 53(21): 11498-506, 2014 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-25333867

RESUMEN

A novel "turn-on" phosphorescent chemodosimeter based on a cyclometalated Ir(III) complex has been designed and synthesized, which displays high selectivity and sensitivity toward Hg(2+) in aqueous media with a broad pH range of 4-10. Furthermore, by time-resolved photoluminescence techniques, some interferences from the short-lived background fluorescence can be eliminated effectively and the signal-to-noise ratio of the emission detection can be improved distinctly by using the chemodosimeter. Finally, the chemodosimeter can be used to monitor Hg(2+) effectively in living cells by confocal luminescence imaging.


Asunto(s)
Complejos de Coordinación/química , Iridio/química , Mediciones Luminiscentes , Mercurio/análisis , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Estructura Molecular , Teoría Cuántica , Relación Estructura-Actividad , Factores de Tiempo , Células Tumorales Cultivadas
14.
J Med Virol ; 86(8): 1296-306, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24760738

RESUMEN

Human beta2-glycoprotein I (beta2-GPI) binds to recombinant hepatitis B surface antigen (rHBsAg) and can bind specifically to annexin II, which is located on the cell membrane of human hepatoma SMMC-7721 cells. Viral envelope proteins are essential for mediating cellular entry. The aim of this study was to investigate the role of beta2-GPI in the early stages of hepatitis B virus (HBV) infection. Western blot and qRT-PCR analyses revealed that beta2-GPI expression was upregulated in HepG2.2.15 cells at both the mRNA and protein level and was almost non-existent in 293T and CHO cells. Furthermore, annexin II was expressed at lower levels in HepG2.2.15 cells compared to L02, HepG2, and SMMC-7721 cells. Additionally, ELISA analyses demonstrated that beta2-GPI enhanced the ability of HBsAg to bind to cell surfaces, and there was differential adhesion to L02, HepG2, HepG2.2.15, and 293T cells. Western blot and ELISA were then performed to assess the effects of HBV and the HBsAg domain on beta2-GPI expression in co-transfected 293T cells. This study revealed that HBV and the large HBV envelope protein increased beta2-GPI expression. Further investigation indicated that beta2-GPI colocalized with HBsAg in the cytosol of HepG2.2.15 cells, with sodium taurocholate co-transporting polypeptide (NTCP) on the cell membrane in NTCP-complemented HepG2 cells, and with annexin II in the cytosol of HepG2 and HepG2.2.15 cells. These data suggest that high expression of beta2-GPI enhances HBsAg binding to cell surfaces, thus contributing to virus particle transfer to the NTCP receptor and interaction with annexin II for viral membrane fusion.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatocitos/fisiología , Hepatocitos/virología , Interacciones Huésped-Patógeno , Acoplamiento Viral , beta 2 Glicoproteína I/biosíntesis , Western Blotting , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa
15.
J Ment Health Policy Econ ; 17(4): 163-72, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25599280

RESUMEN

BACKGROUND: A health care system in which there is no separation between prescription and dispensation, combined with a regulated prescription drug market, leads to various generic substitution mechanisms for antidepressants. AIMS OF THE STUDY: We investigated the determinants of generic versus brand-name antidepressant choices in a regulated prescription market where physicians both prescribe and dispense drugs. METHODS: Using data from a sample of one million individuals selected randomly from the registry of National Health Insurance beneficiaries in 2010, and all claims for these one million enrollees between January 1997 and December 2011, we employed logistic regression to examine the choice of generic versus brand-name antidepressants in the Taiwanese prescription drug market. RESULTS: Access to various antidepressant brands varies according to the accreditation level and type of ownership of the healthcare provider. Private healthcare providers and those with lower accreditation levels were more likely to prescribe generic antidepressants compared to their brand-name counterparts. The diversity of products and competition in the molecule market was positively associated with the probability of prescribing generic antidepressants. DISCUSSION: In a regulated prescription drug market with no separation between prescription and dispensation, the substitution of generic antidepressant prescriptions in place of brand-name prescriptions is likely driven by drug and provider market characteristics, rather than by lowering costs. IMPLICATIONS FOR HEALTHCARE PROVISION: The allocation of different types of ownership and accreditation levels of healthcare providers may lead to unequal access to various brands of antidepressants. IMPLICATIONS FOR HEALTH POLICIES: Policies for improving the treatment of depression should take into account the structure of molecule and provider markets as important factors in determining the choice and utilization of antidepressants, in a healthcare system where physicians both prescribe and dispense drugs. IMPLICATIONS FOR FUTURE RESEARCH: Other psychotropic drug classes should be investigated to explore the effect of molecule and provider characteristics on the utilization of various classes of medication.


Asunto(s)
Antidepresivos/economía , Medicamentos Genéricos/economía , Pautas de la Práctica en Medicina/estadística & datos numéricos , Acreditación/estadística & datos numéricos , Adulto , Anciano , Antidepresivos/uso terapéutico , Costos y Análisis de Costo , Depresión/tratamiento farmacológico , Medicamentos Genéricos/uso terapéutico , Femenino , Humanos , Revisión de Utilización de Seguros/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Propiedad , Taiwán
16.
Eur J Health Econ ; 14(2): 287-95, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22200844

RESUMEN

Although the technological change in medicine has been recognized widely as the major driver of rising healthcare costs, there is very little research that estimates this effect directly. This paper uses both a single-equation and a simultaneous equations approach to investigate empirically the interactive relationship between technological innovation and the growth of health expenditure in the context of the pharmaceutical market in Taiwan. Based on observing 182 therapeutic groups between 1997 and 2006, we find evidence to support the argument that technological innovation and health expenditure are determined simultaneously as technological innovation, and that the growth of health expenditure are endogenous rather than exogenous. Specifically, we find that therapeutic groups associated with higher pharmaceutical expenditure are likely to attract more new products to the market. Meanwhile, therapeutic groups with more new products are associated with higher pharmaceutical expenditures. An important implication of the paper is that cost containment policies will affect not only the growth of health expenditure, but also the progress of technological innovation in the health sector.


Asunto(s)
Difusión de Innovaciones , Economía Farmacéutica , Costos de la Atención en Salud , Gastos en Salud , Modelos Económicos , Humanos , Programas Nacionales de Salud , Taiwán
17.
Health Policy ; 108(2-3): 228-35, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23020970

RESUMEN

OBJECTIVES: This paper investigates the determinants of generic entry in the regulated Taiwanese prescription drug market, where physicians both prescribe and dispense drugs. METHODS: Using a sample of 29 ingredients and a population claim data set from 1997-2007, we employ the negative binomial regression to empirically examine the determinants of generic entry in Taiwan. RESULTS: This study finds that the lagged number of competitors, market size, and market share of large-scale medical providers affect generic entry. CONCLUSIONS: The negative effect of large buyers on generic entry implies that rent-seeking behavior appears to create a barrier for generic manufacturers to enter into the Taiwanese prescription drug market.


Asunto(s)
Control de Medicamentos y Narcóticos/legislación & jurisprudencia , Medicamentos Genéricos/uso terapéutico , Medicamentos bajo Prescripción/uso terapéutico , Costos de los Medicamentos , Industria Farmacéutica , Medicamentos Genéricos/economía , Humanos , Mercadotecnía , Pautas de la Práctica en Medicina/estadística & datos numéricos , Medicamentos bajo Prescripción/economía , Taiwán
18.
Dalton Trans ; 41(24): 7382-9, 2012 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-22584469

RESUMEN

This paper describes the synthesis of 1-(pyridine-4-ylmethyl) NHC and their Pd(II) and Ag(I) complexes, which are fully characterized. Interestingly, we have also synthesized a Pd complex 3a-CO(3) using a more direct treatment of K(2)CO(3) with PdCl(2). 3a-CO(3) represents the first reported solid structure of a Pd η(2)-carbonato complex stabilized by an NHC framework. 3a-CO(3) can be easily converted to a PdCl(2) derivative by treating it with chloroform. We have found these palladium complexes mediate the Heck-Mizoroki coupling with a low catalyst loading. Furthermore, we also expand such catalytic manifold toward constructing fused polyaromatic substrates, a highly useful class of compounds in optoelectronic chemistry.

19.
J Health Econ ; 31(3): 471-83, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22525716

RESUMEN

This article investigates the determinants of the prices of pharmaceuticals and their impact on the demand for prescription drugs in the context of Taiwan's pharmaceutical market where medical providers earn profit directly from prescribing and dispensing drugs. Based on product-level data, we find evidence that the profit-seeking behavior of the medical providers in the prescription drug market transfers the force of competition from the unregulated wholesale market to the regulated retail market and hence market competition still plays an important role in the determination of the regulated price. We also find that the profit-seeking behavior plays a similar role to advertising in that it increases the brand loyalty and hence lowers price elasticity. An important implication of our study is that the institutional features in the pharmaceutical market matter in shaping the nature of pharmaceutical competition and the responsiveness of pharmaceutical consumption with respect to changes in price.


Asunto(s)
Competencia Económica , Regulación Gubernamental , Medicamentos bajo Prescripción/economía , Mecanismo de Reembolso/economía , Humanos , Programas Nacionales de Salud , Medicamentos bajo Prescripción/provisión & distribución , Taiwán , Cobertura Universal del Seguro de Salud
20.
Value Health ; 15(1 Suppl): S35-42, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22265065

RESUMEN

OBJECTIVE: To provide an overview of the use of biologics in Taiwan, including the access to new biologics, the impact of this access on the growth of health-care expenditure, and the utilization patterns. METHODS: We first conducted a market-level analysis to investigate the availability of global biologics in Taiwan as well as the growth and concentration of aggregate spending on biologics. We then conducted a patient-level analysis to investigate the costs and utilization patterns for selected new biologics. RESULTS: We found that the concentration index is such that the 20 leading biologics in Taiwan account for more than 90% of the total spending on biologics. In our patient-level study on four biologics, the annual cost of treatment per patient ranged from NT$100,000 to NT$400,000. The prevalence rate of the user was between 6.5 and 37.2 per 100,000 of population. The treatment costs were inversely related to the prevalence rate of users. We also found that physicians in larger and public hospitals were more likely to prescribe new biologics to their patients compared with their counterparts practicing in smaller and private hospitals. In addition, we found that physicians were more likely to prescribe biologics to patients with more severe diseases and higher comorbidities. CONCLUSIONS: We conclude that public spending on biologics in Taiwan is highly targeted toward about 20 products with higher annual expenditures and growth rates and that the utilization of these biologics is targeted at a small number of patients. In addition, the access to these costly biologics is not uniform among patients in a country with universal coverage for prescription drugs.


Asunto(s)
Productos Biológicos/administración & dosificación , Productos Biológicos/economía , Honorarios Farmacéuticos/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/economía , Anciano , Costos y Análisis de Costo , Utilización de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina , Taiwán
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