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91.
Syntheses of carbohydrate-functionalized platinum complexes resembling presently employed cytostatics were performed. Mono-allylated sugar substrates obtained in two steps from glucose and galactose were connected with 2-allyl diethyl malonate by cross-metathesis. Following hydrogenation and acidic cleavage of the ester and alkylidene functionalities gave dicarboxylated glycoconjugates, which were transformed into their diammine platinum complexes. The antitumor activities of these platinum complexes were checked by sensitivity testing with 11 lung cancer cell lines. The novel glucose-platinum complex proved to be comparable to the drug carboplatin.  相似文献   
92.
Two new prodrugs, bearing two and three 5‐fluorouracil (5‐FU) units, respectively, have been synthesized and were shown to efficiently treat human breast cancer cells. In addition to 5‐FU, they were intended to form complexes through H‐bonds to an organo‐bridged silane prior to hydrolysis‐condensation through sol–gel processes to construct acid‐responsive bridged silsesquioxanes (BS). Whereas 5‐FU itself and the prodrug bearing two 5‐FU units completely leached out from the corresponding materials, the prodrug bearing three 5‐FU units was successfully maintained in the resulting BS. Solid‐state NMR (29Si and 13C) spectroscopy show that the organic fragments of the organo‐bridged silane are retained in the hybrid through covalent bonding and the 1H NMR spectroscopic analysis provides evidence for the hydrogen‐bonding interactions between the prodrug bearing three 5‐FU units and the triazine‐based hybrid matrix. The complex in the BS is not affected under neutral medium and operates under acidic conditions even under pH as high as 5 to deliver the drug as demonstrated by HPLC analysis and confirmed by FTIR and 13C NMR spectroscopic studies. Such functional BS are promising materials as carriers to avoid the side effects of the anticancer drug 5‐FU thanks to a controlled and targeted drug delivery.  相似文献   
93.
We have developed core‐shell‐corona‐type polymeric micelles that can integrate multiple functions in one system, including the capability of accommodating hydrophobic dyes into core and hydrophilic drug into the shell, as well as pH‐triggered drug‐release. The neutral and hydrophilic corona sterically stabilizes the multifunctional polymeric micelles in aqueous solution. The mineralization of calcium phosphate (CaP) on the PAA domain not only enhances the diagnostic efficacy of organic dyes, but also works as a diffusion barrier for the controlled release.  相似文献   
94.
Hydrophobicity has been an obstacle that hinders the use of many anticancer drugs. A critical challenge for cancer therapy concerns the limited availability of effective biocompatible delivery systems for most hydrophobic therapeutic anticancer drugs. In this study, we have developed a targeted near‐infrared (NIR)‐regulated hydrophobic drug‐delivery platform based on gold nanorods incorporated within a mesoporous silica framework (AuMPs). Upon application of NIR light, the photothermal effect of the gold nanorods leads to a rapid rise in the local temperature, thus resulting in the release of the entrapped drug molecules. By integrating chemotherapy and photothermotherapy into one system, we have studied the therapeutic effects of camptothecin‐loaded AuMP‐polyethylene glycol‐folic acid nanocarrier. Results revealed a synergistic effect in vitro and in vivo, which would make it possible to enhance the therapeutic effect of hydrophobic drugs and decrease drug side effects. Studies have shown the feasibility of using this nanocarrier as a targeted and noninvasive remote‐controlled hydrophobic drug‐delivery system with high spatial/temperal resolution. Owing to these advantages, we envision that this NIR‐controlled, targeted drug‐delivery method would promote the development of high‐performance hydrophobic anticancer drug‐delivery system in future clinical applications.  相似文献   
95.
Electrophoresis 2014, 35, 1504–1508. DOI: 10.1002/elps.201400001 Combination of DNA biobarcode assay with micro‐capillary electrophoretic analysis on a chip allows us to perform breast and colorectal cancer cell detection with high sensitivity, multiplexity, and accuracy.

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96.
97.
Metabolic profiles from human urine reveal the significant difference of carnitine and acylcarnitines levels between non‐small cell lung carcinoma patients and healthy controls. Urine samples from cancer patients and healthy individuals were assayed in this metabolomic study using ultra high performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry. The data were normalized by the sum of all intensities and creatinine calibration, respectively, before orthogonal partial least squares discriminant analysis. Twenty differential metabolites were identified based on standard compounds or tandem mass spectrometry fragments. Among them, some medium‐/long‐chain acylcarnitines, for example, cis‐3,4‐methylene heptanoylcarnitine, were found to be downregulated while carnitine was upregulated in urine samples from the cancer group compared to the control group. Receiver operating characteristic analysis of the two groups showed that the area under curve for the combination of carnitine and 11 selected acylcarnitines was 0.958. This study suggests that the developed carnitine and acylcarnitines profiling method has the potential to be used for screening non‐small cell lung carcinoma.  相似文献   
98.
We report in this study the effects of red-emitting CdTe QDs capped with cysteamine(Cys-CdTe) on the in vitro anticancer activity of the well-known flavenoid quercetin(Qu). Various techniques, including the methylthiazolyldiphenyl-tetrazolium bromide assay, the real-time cell electronic sensing system, the optical and fluorescence imaging, and electrochemical methods have been utilized to study the potential interactions of Cys-CdTe QDs with Qu. The observations demonstrate that the safe-dosage Cys-CdTe QDs can greatly improve the drug uptake and enhance the inhibition efficiency of Qu towards the proliferation of cancer cells such as HepG2 cells. This study implies that Cys-CdTe QDs may be used for cancer therapy and that they exert a synergic anticancer effect when bound to drug molecules.  相似文献   
99.
Urine is considered as one of the diagnostically important bio fluids, as it has many metabolites. The distribution and the physiochemical properties of the metabolites may vary during any altered metabolic and pathological conditions. Raman spectroscopy was employed in the characterization of the metabolites of human urine of normal subjects and oral cancer patients in the finger print region (500–1800 cm−1). Principal component analysis‐based linear discriminant analysis was performed to discriminate cancer patients from normal subjects. The discriminant analysis classifies the cancer patients from normal subjects with a sensitivity and specificity of 98.6% and 87.1%, respectively, with an overall accuracy of 93.7%. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
100.
Cancer is a highly heterogenous disease that requires precise detection tools and active surveillance methods. Liquid biopsy assays provide an agnostic way to follow the complex trajectory of cancer, providing better patient stratification tools for optimized treatment. Here, we present the development of a low-volume liquid biopsy assay called cyc-DEP (cyclic immunofluorescent imaging on dielectrophoretic chip) to profile biomarkers collected on a dielectrophoretic microfluidic chip platform. To enable on-chip cyclic imaging, we optimized a fluorophore quenching method and sequential rounds of on-chip staining with fluorescently conjugated primary antibodies. cyc-DEP allows for the quantification of a multiplex array of proteins using 25 µl of a patient plasma sample. We utilized nanoparticles from a prostate adenocarcinoma (LNCaP) cell line and a panel of six target proteins to develop our proof-of-concept technique. We then used cyc-DEP to quantify blood plasma levels of target proteins from healthy individuals, low-grade and high-grade prostate cancer patients (n = 3 each) in order to demonstrate that our platform is suitable for liquid biopsy analysis in its present form. To ensure accurate quantification of signal intensities and comparisons between different samples, we incorporated a signal intensity normalization method (fluorescent beads) and a custom signal intensity quantification algorithm that account for the distribution of signal across hundreds of collection regions on each chip. Our technique enabled a threefold improvement in multiplicity for detecting proteins associated with fluid samples, opening doors for early detection, and active surveillance through quantification of a multiplex array of biomarkers from low-volume liquid biopsies.  相似文献   
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