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排序方式: 共有224条查询结果,搜索用时 742 毫秒
51.
Ayako Oda Yosuke Suzuki Banri Sato Haruki Sato Ryota Tanaka Hiroyuki Ono Tadasuke Ando Toshitaka Shin Hiromitsu Mimata Hiroki Itoh Keiko Ohno 《Journal of separation science》2022,45(10):1672-1682
Indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid are uremic toxins that accumulate in renal failure and have been reported to decrease the activities of the drug-metabolizing enzyme cytochrome P450 3A and the drug transporter organic anion transporting polypeptides 1B, respectively. In this study, we established and validated an assay for simultaneous quantification of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid in human plasma. The samples were pretreated by solid-phase extraction, and measured by ultra-high-performance liquid chromatography–tandem mass spectrometry. The validation results for this assay were within the acceptable limits recommended by the US Food and Drug Administration, with a lower limit of quantitation of 0.05 μg/mL for both indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid. Recovery rates of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 100.7–101.9 and 100.2–101.3%, respectively. Matrix effects of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 101.1–105.5 and 97.0–103.8%, respectively. The validated assay was used to analyze indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations in the plasma samples of healthy volunteers and patients with chronic kidney disease. All the measured plasma indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations were within the calibration ranges. This novel method may contribute to predicting the activities of drug-metabolizing enzymes and drug transporters in individual patients. 相似文献
52.
Yun‐Gon Kim Geun‐Cheol Gil Kyung‐Soon Jang Sukmook Lee Hyoung‐Il Kim Jung‐Sik Kim Junho Chung Chung‐Gyu Park David J. Harvey Byung‐Gee Kim 《Journal of mass spectrometry : JMS》2009,44(7):1087-1104
N‐glycan structures released from miniature pig endothelial and islet cells were determined by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF), negative ion electrospray ionization (ESI) MS/MS and normal‐phase high performance liquid chromatography (NP‐HPLC) combined with exoglycosidase digestion. Totally, the identified structures were 181 N‐glycans including 129 sialylated and 18 α‐galactosylated glycans from pig endothelial cells and 80 N‐glycans including 41 sialylated and one α‐galactosylated glycans from pig islet cells. The quantity of the α‐galactosylated glycans from pig islet cells was certainly neglectable compared to pig endothelial cells. A number of NeuGc‐terminated N‐glycans (80 from pig endothelial cells and 13 from pig islet cells) are newly detected by our mass spectrometric strategies. The detailed structural information will be a matter of great interest in organ or cell xenotransplantation using α 1,3‐galactosyltransferase gene‐knockout (GalT‐KO) pig. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
53.
Myroslav Zoriy Andreas Matusch Thilo Spruss J. Sabine Becker 《International journal of mass spectrometry》2007,260(2-3):102
Platinum complexes are used for the treatment of several types of cancer. High platinum concentrations in the target tissue and low concentrations in dose-limiting tissue structures such as renal tubules are desirable to assure selective toxicity. Microlocal analysis of platinum distribution in tissue sections may thus contribute to the optimization of platinum therapy. Scanning laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to produce images of element distribution in 14-μm thin sections of kidney tissue from a mouse treated with cis-platin 60 min prior to victimization. The sample surface was scanned (raster area 300 mm2) with a focused laser beam (wavelength 266 nm, diameter of laser crater 50 μm, inter line distance 50 μm and laser power density 3 × 109 W cm−2) in a cooled laser ablation chamber (about −15 °C) developed for these measurements. The laser ablation system was coupled to a double-focusing sector field ICP-MS. Ion intensities of 63Cu+, 64Zn+, and 196Pt+ were measured within the tissue by LA-ICP-MS. Matrix-matched laboratory standards served for calibration of analytical data. The mass spectrometric analysis yielded an inhomogeneous distribution for Cu, Zn, and Pt in thin kidney sections. Copper was enriched in the capsule and outer cortex, zinc in the inner cortex and the platinum concentration followed a centripetal gradient with clear medullar enrichment. Thus, scanning LA-ICP-MS may be a useful tool in the preclinical development of new and less nephrotoxic platinum complexes. 相似文献
54.
《Arabian Journal of Chemistry》2022,15(7):103892
The purpose of this study was to illustrate the mechanism of “enzyme inactivation and toxicity reduction” of Fructus Tribuli (FT) after being heating processed. Ultra-high performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UHPLC-MS/MS) was used to quantitatively analyze the contents of four steroidal saponins in crude Fructus Tribuli (CFT) and stir-fried Fructus Tribuli (SFT) under different storage times at room temperature. The enzyme activity of β-D-glucosidase in CFT and SFT were determined and calculated by ultraviolet–visible spectrometry (UV-VIS spectrometry). In addition, the enzyme hydrolysates of FOT and tribuluside A were qualitatively analyzed by ultra-high-performance liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS). The hepatorenal toxicity of spirostanol saponins in FT were further confirmed by in vivo and in vitro experiment. This study confirmed that “enzyme inactivation and toxicity reduction” was one of the reasons why the stir-frying can reduce hepatorenal toxicity of FT, and further enriched the exploration on the mechanism of processing toxicity reduction. 相似文献
55.
不孕症的中药治疗与微量元素 总被引:4,自引:0,他引:4
吕明松 《广东微量元素科学》1998,5(11):26-28
重点讨论了不孕症的发病机制,用中医中药辨证组方治疗的优势和现代微量元素研究的关系。 相似文献
56.
Nishimura K Tsumagari H Morioka A Yamauchi Y Miyashita K Lu S Jisaka M Nagaya T Yokota K 《Applied biochemistry and biotechnology》2002,102(1-6):239-250
The arachidonate cascade includes the cyclooxygenase (COX) pathway to form prostanoids and the lipoxygenase (LOX) pathway
to generate several oxygenated fatty acids, collectively called eicosanoids. Eicosanoids are suggested to play a dual role
in regulating cell survival and apoptosis in various types of cells through an unknown mechanism. We found apoptosis in cultured
Madin-Darby canine kidney (MDCK) cells treated with 12-O-tetradecanoylphorbol β-acetate (TPA), a potent tumor promoter, and nordihydroguaiaretic acid (NDGA), a LOX inhibitor. The
effect of TPA was synergistically stimulated along with NDGA. Aspirin, a COX inhibitor, was not effective. The target of NDGA
might be different from the mechanism involving a LOX activity in some kinds of carcinoma cells because the increased expression
of 12-LOX was not detected in MDCK cells treated with TPA. Caspase and poly(ADP-ribose) metabolites were found to be involved
in the signal transduction pathway of the TPA- and NDGA-induced apoptosis in MDCK cells. Alternatively, hydrogen peroxide-induced
apoptosis was not affected by NDGA. Thus, the TPA-induced response involved the mechanism independent of the oxidative stress.
Obesity is a risk factor for severe diseases including noninsulin-dependent diabetes and atherosclerosis characterized by
the changes of cell properties of adipocytes. We found that conjugated linolenic acid from bitter gourd was able to induce
apoptosis in mouse preadipogenic 3T3-L1 cells. The findings provide the potential use of conjugated fatty acids to regulate
obesity. 相似文献
57.
Yusheng Fu Haiyan Tan Xiujian Wu Xiaohe Wu Yongzheng Yang Yanling Gao Ruowei Liu Min Qi Xiaoyun Chen Yaochao Ning Weidong Sun Nianhuan Chang Junjie Ma Kang Cheng Hongni Yang Qing Li Ping Wang Chaoran Wu Hong Xian Li Wang 《Electrophoresis》2021,42(9-10):1043-1049
Currently, the global healthcare market is increasing at high speed with the impendent global aging issue. Healthcare Industry 4.0 has emerged as an efficient solution towards the aging issue since it was integrated with ubiquitous medical sensors, big health processing platform, high bandwidth, speed technologies, and medical services, etc. It is believed to fulfil the requirement of the tremendously growing health market. The acquisition of medical data acts as the dominant precondition to implement the Healthcare Industry 4.0. In the same way, the widely available smartphone could serve as the best biomedical information collect station. In this study, a smartphone-powered photochemical dongle is demonstrated to precisely estimate blood creatinine from the fingertip blood, which works as a highly compact reflectance spectral analyzer with an enzymatically dry chemical test strip. Comparing with conventional laboratory facility for the evaluation and treatment of chronic kidney disease (CKD), it implemented the platform of point care with agreed accuracy. In order to estimate the efficiency of treatment and recovery of the CKD, the proposed photochemical dongle would provide a flexible and rapid platform for point of care. Furthermore, the proposed measured technology is very promising method for remote CKD management. 相似文献
58.
Kei Toda Haruka KuwaharaHidetaka Kajiwara Kazutoshi HirotaShin-Ichi Ohira 《Analytica chimica acta》2014
The highly odorous compound methanethiol, CH3SH, is commonly produced in biodegradation of biomass and industrial processes, and is classed as 2000 times more odorous than NH3. However, there is no simple analytical method for detecting low parts-per-billion in volume ratio (ppbv) levels of CH3SH. In this study, a micro gas analysis system (μGAS) was developed for continuous or near real time measurement of CH3SH at ppbv levels. In addition to a commercial fluorescence detector, a miniature high sensitivity fluorescence detector was developed using a novel micro-photomultiplier tube device. CH3SH was collected by absorption into an alkaline solution in a honeycomb-patterned microchannel scrubber and then mixed with the fluorescent reagent, 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F). Gaseous CH3SH was measured without serious interference from other sulfur compounds or amines. The limits of detection were 0.2 ppbv with the commercial detector and 0.3 ppbv with the miniature detector. CH3SH produced from a pulping process was monitored with the μGAS system and the data agreed well with those obtained by collection with a silica gel tube followed by thermal desorption–gas chromatography–mass spectrometry. The portable system with the miniature fluorescence detector was used to monitor CH3SH levels in near-real time in a stockyard and it was shown that the major odor component, CH3SH, presented and its concentration varied dynamically with time. 相似文献
59.
Cassandra Millet-Boureima Roman Rozencwaig Felix Polyak Chiara Gamberi 《Molecules (Basel, Switzerland)》2020,25(22)
Autosomal dominant polycystic kidney disease (ADPKD) causes progressive cystic degeneration of the renal tubules, the nephrons, eventually severely compromising kidney function. ADPKD is incurable, with half of the patients eventually needing renal replacement. Treatments for ADPKD patients are limited and new effective therapeutics are needed. Melatonin, a central metabolic regulator conserved across all life kingdoms, exhibits oncostatic and oncoprotective activity and no detected toxicity. Here, we used the Bicaudal C (BicC) Drosophila model of polycystic kidney disease to test the cyst-reducing potential of melatonin. Significant cyst reduction was found in the renal (Malpighian) tubules upon melatonin administration and suggest mechanistic sophistication. Similar to vertebrate PKD, the BicC fly PKD model responds to the antiproliferative drugs rapamycin and mimics of the second mitochondria-derived activator of caspases (Smac). Melatonin appears to be a new cyst-reducing molecule with attractive properties as a potential candidate for PKD treatment. 相似文献
60.
Siam benzoin is a natural resin that contains up to 65% of coniferyl benzoate. Treatment of this material with an esterase
followed by an alcohol dehydrogenase in a one-pot procedure gave 1.5 g/L coniferaldehyde in 36% molar yield. Several lipases
and esterases were tested, but only pig liver esterase gave significant results. Various alcohol oxidases and alcohol dehydrogenases
were screened for their ability to oxidize coniferyl alcohol to coniferaldehyde. Horse liver alcohol dehydrogenase coupled
with a cofactor regeneration system was the most efficient of the enzymes tested. 相似文献