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71.
72.
Cervix cancer is the second most common cancer among women worldwide, whereas paclitaxel, the first line chemotherapeutic drug used to treat cervical cancer, shows low chemosensitivity on the advanced cervical cancer cell line. Tanshinone IIA (Tan IIA) exhibited strong growth inhibitory effect on CaSki cells (IC50 = 5.51 μM) through promoting caspase cascades with concomitant upregulating the phosphorylation of p38 and JNK signaling. Comprehensive proteomics revealed the global protein changes and the network analysis implied that Tan IIA treatment would activate ER stress pathways that finally lead to apoptotic cell death. Moreover, ER stress inhibitor could alleviate Tan IIA caused cell growth inhibition and ameliorate C/EBP‐homologous protein as well as apoptosis signal‐regulating kinase 1 mediated cell death. The therapeutic interventions targeting the mitochondrial‐related apoptosis and ER stress responses might be promising strategies to conquer paclitaxel resistance.  相似文献   
73.
We investigate the propagation characteristics of the fundamental surface plasmon polariton (SPP) mode of a finite-width metal–dielectric–metal waveguide. By changing the refractive index or the thickness of the dielectric layer of the waveguide, the SPP mode can be transformed from a mode confined in the dielectric layer into a mode confined around the metal corners. There always exists a condition at which the mode field distribution in the dielectric layer becomes almost perfectly uniform along the direction parallel to the metal layers, and this condition is insensitive to the width of the waveguide. It is also possible to obtain an ultra-uniform field distribution by controlling the refractive index of a different dielectric placed on both sides of the waveguide. The waveguide can be used as a basic structure for the realization of nanosized photonic devices and sensors.  相似文献   
74.
A novel C6–C3 prenylated compound, illicarborene A (1), together with illioliganfunone D (2), 1-allyl-3,5-dimethoxy-4-(3-methylbut-2-enyloxy)benzene (3), (?)-illicinone A (4), (?)-illicinone B (5) and (?)-illicinone A derivative (6) was isolated and characterized from the fruits of Illicium arborescens Hayata. Compound 1 possesses a new class of tricyclic 6/6/5 ring system. The structure of 1 was determined by spectroscopic analysis such as 1H–1H COSY, HMQC, HMBC, and NOESY, and confirmed by chemical reaction to yield 7. Compounds 15 were found to increase proliferative activity in primary cell culture of osteoblast cells.  相似文献   
75.

Background

Chronic lymphocytic leukemia (CLL) is much less prevalent in Asian countries. Whether there are differences in survival outcomes between the East and West, however, remain unclear.

Methods

The survival data for CLL patients identified in the Taiwan Cancer Registry database between 1990 and 2004, together with corresponding data in the US Surveillance, Epidemiology, and End Results database, were retrieved. The relative survivals (RS, adjusted for the expected survival in the general population) were estimated in patients diagnosed in three 5-year periods of time.

Results

CLL drastically shortened patients’ life expectancy; more importantly, this negative impact in Taiwan was much larger than that in the US: the 5-year RS in Taiwan and US were 59% and 76%, and the 10-year RS, 45% and 56%, respectively. Nevertheless, survival in Taiwan was better in the periods after 1995 (5-year RS, from 53.0% to 60.6%), a time period corresponding to the introduction of the Taiwan National Health Insurance scheme. Such improvement was largely due to decreased mortality in patients younger than 65 (5-year RS, from 53.5% to 69.1%). Despite the improvement, patients’ RS in Taiwan in recent periods remain steadily 15∼20% inferior to that in the US in both younger and older patient groups.

Conclusions

The improved RS in Taiwan implies that therapeutic advances are changing the prognosis of CLL. The stable RS gap between Taiwanese and the US patients suggests the existence of an ethnic difference in CLL patients’ outcomes.  相似文献   
76.

Background

Enterovirus 71 (EV71) has caused several epidemics of hand, foot and mouth diseases (HFMD) in Asia. No effective EV71 vaccine is available. A randomized and open-label phase I clinical study registered with ClinicalTrials.gov #NCT01268787, aims to evaluate the safety, reactogenicity and immunogenicity of a formalin-inactivated EV71 vaccine candidate (EV71vac) at 5- and 10-µg doses. In this study we report the cross-neutralizing antibody responses from each volunteer against different subgenotypes of EV71 and CVA16.

Methods

Sixty eligible healthy adults were recruited and vaccinated. Blood samples were obtained on day 0, 21 and 42 and tested against B1, B4, B5, C2, C4A, C4B and CVA16 for cross-neutralizing antibody responses.

Results

The immunogenicity of both 5- and 10- µg doses were found to be very similar. Approximately 45% of the participants had <8 pre-vaccination neutralization titers (Nt) against the B4 vaccine strain. After the first EV71vac immunization, 95% of vaccinees have >4-fold increase in Nt, but there was no further increase in Nt after the second dose. EV71vac induced very strong cross-neutralizing antibody responses in >85% of volunteers without pre-existing Nt against subgenotype B1, B5 and C4A. EV71vac elicited weak cross-neutralizing antibody responses (∼20% of participants) against a C4B and Coxsackie virus A16. Over 90% of vaccinated volunteers did not develop cross-neutralizing antibody responses (Nt<8) against a C2 strain. EV71vac can boost and significantly enhance the neutralizing antibody responses in volunteers who already had pre-vaccination antibodies against EV71 and/or CVA16.

Conclusion

EV71vac is efficient in eliciting cross-neutralizing antibody responses against EV71 subgenotypes B1, B4, B5, and C4A, and provides the rationale for its evaluation in phase II clinical trials.

Trial Registration

ClinicalTrials.gov __NCT01268787  相似文献   
77.

Background

Thyroid disorders have long been associated with psychiatric illness, often with symptoms suggestive of mood disorders. The most common clinical features associated with hyperthyroidism are anxiety and depression. The risk of bipolar disorders, especially bipolar mania, among patients with thyroid disorders has not been well characterized.

Objective

We explored the relationship of hyperthyroidism and the subsequent development of bipolar disorders, and examined the risk factors for bipolar disorders in patients with hyperthyroidism.

Methods

We identified patients who were diagnosed with hyperthyroidism between 2000 and 2010 in the Taiwan National Health Insurance Research Database. A comparison cohort without hyperthyroidism was matched based on age, sex, and comorbidities. The occurrence of bipolar disorders was evaluated in both cohorts based on diagnosis and the use of mood stabilizer drugs.

Results

The hyperthyroidism cohort consisted of 21, 574 patients, and the comparison cohort consisted of 21, 574 matched control patients without hyperthyroidism. The incidence of bipolar disorders (incidence rate ratio [IRR], 2.31, 95% CI 1.80–2.99, P<.001) was higher for the hyperthyroidism patients than the control patients. Multivariate, matched regression models showed that women (HR 2.02, 95% CI 1.34–3.05, P = .001), patients with alcohol use disorders (HR 3.03, 95% CI 1.58–5.79, P = .001), and those with asthma (HR 1.70, 95% CI 1.18–2.43, P = .004) were independent risk factors for the development of bipolar disorders in hyperthyroidism patients.

Conclusions

Although a possibility that the diagnosis of bipolar disorders in this study actually includes "bipolar disorders due to hyperthyroidism" cannot be excluded, this study suggests that hyperthyroidism may increase the risk of developing bipolar disorders.  相似文献   
78.
Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, can elicit anti-tumor effects in various malignancies. Here, we sought to clarify the role of autophagy in celecoxib-induced cytotoxicity in human urothelial carcinoma (UC) cells. The results shows celecoxib induced cellular stress response such as endoplasmic reticulum (ER) stress, phosopho-SAPK/JNK, and phosopho-c-Jun as well as autophagosome formation in UC cells. Inhibition of autophagy by 3-methyladenine (3-MA), bafilomycin A1 or ATG7 knockdown potentiated celecoxib-induced apoptosis. Up-regulation of autophagy by rapamycin or GFP-LC3B-transfection alleviated celecoxib-induced cytotoxicity in UC cells. Taken together, the inhibition of autophagy enhances therapeutic efficacy of celecoxib in UC cells, suggesting a novel therapeutic strategy against UC.  相似文献   
79.
Abstract

Biodegradable polymers are promising binders and carriers for natural antifoulants. In the present study, an antifouling (AF) coating was developed by adding a non-toxic AF compound (butenolide) to a bio-based and biodegradable poly(lactic acid)-based polyurethane. Mass loss measurement showed that the polymer degraded in seawater at a rate of 0.013?mg cm?2?day?1. Measurements showed that butenolide was released from the coatings into seawater over a period of at least three months. Both the concentration of butenolide in the coatings and the ambient temperature determined the release rate of butenolide. The results further demonstrate that incorporating rosin into the coatings increase the self-renewal rate of the polymer and facilitated the long-term release of butenolide from the coating. The results show that poly(lactic acid)-based polyurethane is a suitable polymer for butenolide-based AF coatings.  相似文献   
80.
The QT interval is a recording of cardiac electrical activity. Previous genome-wide association studies identified genetic variants that modify the QT interval upstream of LITAF (lipopolysaccharide-induced tumor necrosis factor-α factor), a protein encoding a regulator of endosomal trafficking. However, it was not clear how LITAF might impact cardiac excitation. We investigated the effect of LITAF on the voltage-gated sodium channel Nav1.5, which is critical for cardiac depolarization. We show that overexpressed LITAF resulted in a significant increase in the density of Nav1.5-generated voltage-gated sodium current INa and Nav1.5 surface protein levels in rabbit cardiomyocytes and in HEK cells stably expressing Nav1.5. Proximity ligation assays showed co-localization of endogenous LITAF and Nav1.5 in cardiomyocytes, whereas co-immunoprecipitations confirmed they are in the same complex when overexpressed in HEK cells. In vitro data suggest that LITAF interacts with the ubiquitin ligase NEDD4-2, a regulator of Nav1.5. LITAF overexpression down-regulated NEDD4-2 in cardiomyocytes and HEK cells. In HEK cells, LITAF increased ubiquitination and proteasomal degradation of co-expressed NEDD4-2 and significantly blunted the negative effect of NEDD4-2 on INa. We conclude that LITAF controls cardiac excitability by promoting degradation of NEDD4-2, which is essential for removal of surface Nav1.5. LITAF-knockout zebrafish showed increased variation in and a nonsignificant 15% prolongation of action potential duration. Computer simulations using a rabbit-cardiomyocyte model demonstrated that changes in Ca2+ and Na+ homeostasis are responsible for the surprisingly modest action potential duration shortening. These computational data thus corroborate findings from several genome-wide association studies that associated LITAF with QT interval variation.  相似文献   
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