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951.
Codonopsis lanceolata extract (CLE) has been used in traditional medicine in the Asian-Pacific region for the treatment of bronchitis, cough, and inflammation. However, it is still unclear whether obesity in mice can be altered by diet supplementation with CLE. To investigate whether CLE could have preventative effects on high fat diet (HFD)-induced obesity, male C57BL/6 mice were placed on either a normal chow diet, 60% HFD, or a HFD supplemented with CLE (60, 180, and 360 mg/kg/day) for 12 weeks. CLE decreased body weight and subcutaneous and visceral fat weights in HFD-induced obese mice. CLE group mice showed lower fat accumulation and a smaller adipocyte area in the adipose tissue compared with the HFD group mice. CLE group mice exhibited lower serum levels of triglycerides, total cholesterol, low density lipoprotein (LDL), glucose, and insulin compared with the HFD group mice. In addition, CLE decreased liver weight and lowered the increase in aspartate aminotransferase (AST) and alanine transaminase (ALT) levels in HFD-induced obese mice. These results indicate that CLE can inhibit the development of diet-induced obesity and hyperlipidemia in C57BL/6 mice.  相似文献   
952.

Objectives

According to the Korea Centers for Disease Control and Prevention, new active tuberculosis (TB) cases have increased since 2001. Some key factors explain and characterize the transmission dynamics of Korean TB infection, such as a higher ratio of latent individuals and a new reporting system implemented in 2001, among others.

Methods

We propose a mathematical TB model that includes exogenous reinfection to gain a better understanding of the recent trend for TB incidence. We divide the simulation time window into two periods, 1970–2000 and 2001–2012, according to the implementation date of a new TB detection system.

Results

Two sets of parameters, including the transmission rate, the latent period, the recovery rate, and the proportion of exogenous reinfection, are estimated using the least-squares method and calibrated to data on the incidence of active TB.

Conclusion

Among some key parameters in the model, the case finding effort turned out to be the most significant impacting component on the reduction in the active TB cases.  相似文献   
953.
A recent trend in urine drug testing in forensic and clinical toxicology has been the simultaneous determination of different chemical groups of target drugs, which are selected based on their local popularity. Rapid multiple drug analysis, made possible by the use of liquid chromatography–tandem mass spectrometry (LC/MS/MS), has become more widely used, especially in workplace drug testing. Therefore, in the present study, a method for simultaneously analyzing 35 drugs of abuse and relevant metabolites that are most prevalent in Korea, using LC/MS/MS with polarity switching electrospray ionization, was developed and validated. The drugs and metabolites in urine were extracted by using mixed mode strong cation exchange polymeric solid phase extraction cartridges after enzymatic hydrolysis and were then injected into the LC/MS/MS system. The validation results for selectivity, linearity, intra- and inter-assay precision and accuracy for this method were satisfactory, while the results for matrix effects and recovery showed significant variance among the urine samples from different sources. The limits of detection ranged from 0.1 to 10 ng/ml and the limits of quantification were from 1 to 10 ng/ml. To reduce the matrix effects in authentic samples, two different quantitative approaches were compared: quantification using calibration standards prepared by the drug-free pooled urine matrix and quantification using the standard addition. Of these, the latter method was found to be the most suitable. The method developed in this study will be very useful for forensic and clinical toxicology laboratories to adopt for monitoring the inappropriate use of controlled drugs.  相似文献   
954.
Homoegonol is a lignan derived from styraxlignolide A, which was isolated from Styrax japonica, a medicinal plant widely used for treatment of inflammatory diseases in Korea. We investigated the efficacy of homoegonol for the treatment of allergic asthma using an ovalbumin (OVA)-induced murine asthma model. The mice were sensitized through intraperitoneal injections of OVA on days 0 and 14. On days 21, 22 and 23 after the initial OVA sensitization, the mice were received OVA airway challenge. Homoegonol was administered by oral gavage at a dose of 30 mg/kg 1 h prior to the OVA challenge. The homoegonol-treated mice exhibited reduced inflammatory cell counts and Th2 cytokines in BALF, AHR, and IgE in the serum compared with the OVA-sensitized/challenged mice. The histological analysis of the lung tissue revealed that the administration of homoegonol attenuated the airway inflammation and the mucus overproduction in airway epithelial lesions induced by OVA through a reduction in expression of inducible nitric oxide synthase and matrix metalloproteinase-9. These findings indicate that homoegonol effectively suppresses the asthmatic responses induced by OVA challenge and suggests that homoegonol exhibits potential as therapeutic drug for allergic asthma.  相似文献   
955.

Objectives:

Local strategies directed against vascular smooth muscle cell (VSMC) proliferation, such as drug-eluting stents (DES), reduce the occurrence of restenosis. However, these approaches may also inhibit vascular endothelial cell (VEC) proliferation and impair reendothelialization, and hence, increase susceptibility to late thrombosis. In this study we examined the differential effects of various concentrations of the type 5 phosphodiesterase (PDE-5) inhibitor, udenafil, on viability, proliferation, and apoptosis of VEC and VSMC, in order to identify the optimal concentration of udenafil that minimizes inhibition of VEC survival and growth, and maximizes inhibition of VSMC survival and growth.

Materials and Methods:

VEC from human umbilical veins and VSMC from human aorta were exposed to various concentrations of udenafil (1, 10, and 100 μmol/l and 1 mmol/l) for 24 h, and its effects on cell viability, proliferation, and apoptosis were studied using 5-bromo-2’- deoxyuridine (BrdU), methylthiazoletetrazolium (MTT) assay, trypan blue dye exclusion, and flow cytometry.

Results:

Udenafil inhibited the survival and growth of VEC and VSMC in a concentration-dependent manner over a range of concentrations. At 100 μmol/l, udenafil, inhibited VEC proliferation significantly less than VSMC proliferation (P < 0.05), and could significantly induce VEC apoptosis less than VSMC apoptosis (P < 0.05).

Conclusions:

Udenafil has a differential effect on survival and growth in VEC and VSMC. The maximal differential effect, with minimal inhibition of VEC and maximal inhibition of VSMC, occurs at 100 μmol/l. This characteristic suggests that udenafil is a promising agent for use in DES.KEY WORDS: Drug-eluting stent, proliferation, udenafil  相似文献   
956.
Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate‐coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
957.

Purpose

A novel PEGylated and heparinized magnetic iron oxide nano-platform (DNPH) was synthesized for simultaneous magnetic resonance imaging (MRI) and tumor targeting.

Methods

Starch-coated magnetic iron oxide nanoparticles (“D”) were crosslinked, aminated (DN) and then simultaneously PEGylated and heparinized with different feed ratios of PEG and heparin (DNPH1-4). DNPH products were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID). The magentic targeting of DNPH3, with appropriate amounts of conjugated PEG and heparin, in a mouse 9L-glioma subcutaneous tumor model was confirmed by magnetic resonance imaging (MRI)/electron spin resonance (ESR).

Results

DNPH3 showed long circulating properties in vivo (half-life >8 h, more than 60-fold longer than that of parent D) and low reticuloendothelial system (RES) recognition in liver and spleen. Protamine, a model cationic protein, was efficiently loaded onto DNPH3 with a maximum loading content of 26.4 μg/mg Fe. Magnetic capture of DNPH3 in tumor site with optimized conditions (I.D. of 12 mg/kg, targeting time of 45 min) was up to 29.42 μg Fe/g tissue (12.26% I.D./g tissue).

Conclusion

DNPH3 showed the potential to be used as a platform for cationic proteins for simultaneous tumor targeting and imaging.  相似文献   
958.

Purpose

To investigate whether delivery of a histone deacetylase inhibitor, vorinostat (VOR), by using solid lipid nanoparticles (SLNs) enhanced its bioavailability and effects on multidrug-resistant cancer cells.

Methods

VOR-loaded SLNs (VOR-SLNs) were prepared by hot homogenization using an emulsification-sonication technique, and the formulation parameters were optimized. The cytotoxicity of the optimized formulation was evaluated in cancer cell lines (MCF-7, A549, and MDA-MB-231), and pharmacokinetic parameters were examined following oral and intravenous (IV) administration to rats.

Results

VOR-SLNs were spherical, with a narrowly distributed average size of ~100 nm, and were physically stable for 3 months. Drug release showed a typical bi-phasic pattern in vitro, and was independent of pH. VOR-SLNs were more cytotoxic than the free drug in both sensitive (MCF-7 and A549) and resistant (MDA-MB-231) cancer cells. Importantly, SLN formulations showed prominent cytotoxicity in MDA-MB-231 cells at low doses, suggesting an ability to effectively counter the P-glycoprotein-related drug efflux pumps. Pharmacokinetic studies clearly demonstrated that VOR-SLNs markedly improved VOR plasma circulation time and decreased its elimination rate constant. The areas under the VOR concentration-time curve produced by oral and IV administration of VOR-SLNs were significantly greater than those produced by free drug administration. These in vivo results clearly highlighted the remarkable potential of SLNs to augment the bioavailability of VOR.

Conclusions

VOR-SLNs successfully enhanced the oral bioavailability, circulation half-life, and chemotherapeutic potential of VOR.  相似文献   
959.
Cosmetics are normally composed of various ingredients. Some cosmetic ingredients can act as chemical haptens reacting toward proteins or peptides of human skin and they can provoke an immunologic reaction, called as skin sensitization. This haptenation process is very important step of inducing skin sensitization and evaluating the sensitizing potentials of cosmetic ingredients is very important for consumer safety. Therefore, animal alternative methods focusing on monitoring haptenation potential are undergoing vigorous research. To examine the further usefulness of spectrophotometric methods to monitor reactivity of chemicals toward peptides for cosmetic ingredients. Forty chemicals (25 sensitizers and 15 non-sensitizers) were reacted with 2 synthetic peptides, e.g., the cysteine peptides (Ac-RFAACAA-COOH) with free thiol group and the lysine peptides (Ac-RFAAKAA-COOH) with free amine group. Unreacted peptides can be detected after incubating with 5,5′-dithiobis-2-nitrobenzoic acid or fluorescamine™ as detection reagents for free thiol and amine group, respectively. Chemicals were categorized as sensitizers when they induced more than 10% depletion of cysteine peptides or more than 30% depletion of lysine peptides. The sensitivity, specificity, and accuracy were 80.0%, 86.7% and 82.5%, respectively. These results demonstrate that spectrophotometric methods can be an easy, fast, and high-throughput screening tools predicting the skin sensitization potential of chemical including cosmetic ingredient.  相似文献   
960.
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