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71.
A Sprague-Dawley rat model with DS sarcoma transplanted in the thigh was used to compare transcatheter locoregional i.a. and systemic i.v. administration of 5-fluorouracil (FU) at 12 dose-rate schedules: 25, 50 and 100 mg/kg; bolus, 1, 5 and 24 h infusions. In experiment A tumor (62/67 animals) as well as liver and kidney (56/67 animals) were excised 1 h after a single bolus or 1 h infusion or at the end of 5 and 24 h infusions. (19)F-NMR spectroscopy at 11.7 T was used to quantitate FU and its metabolites in ca. 1 g of tissue at 4 degrees C. In experiment B analogous FU treatments were repeated for 5 days (rats 80+11 controls). Tumor volumes vs time, various blood parameters and survival times were recorded, and a log growth rate parameter log GR, a response index RI, and a toxicity index TI were calculated. The i.a. vs i.v. ratios for tumor concentrations of FU and total anabolites (F-Nucl) were >1 for nearly all treatments and increased with infusion time at the higher doses. F-Nucl in tumor correlated linearly with total fluorine concentration (Tot. F range 30-1100 nmol/g) over all treatments (r=0.92, slope=0.45, p<0.0001). For non-bolus i.v. treatments [FU+F-Nucl] decreased linearly with decreasing FU dose rate (r(2)=0.74, zero intercept), while i.a. treatments showed non-linear behavior. For non-bolus treatments the mean log GR per treatment group showed a negative correlation (r=-0.87) with log[F-Nucl]. The most effective non-toxic treatments were 25 mg/kg over 5 or 24 h; the i.a. route was superior to i.v. on the basis of [FU+F-Nucl], RI, the reduction in log GR, and Kaplan-Meier survival statistics. For liver and kidney Tot. F (>83% FU catabolites) reached ca. 3-4 and 6-7 micromol/g, respectively, at the highest dose rates for either route; F-Nucl were detected only for Tot. F>500 nmol/g and increased exponentially as Tot. F increased (toxic treatments). The concentrations of the main catabolite (alpha-fluoro-beta-alanine, FBAL) in tumor did not correlate with Tot. F but rather with FBAL levels in kidney (r=0.90, all treatments), indicating that uptake of liver-derived FBAL from the circulation is the major source of FBAL in tumor.  相似文献   
72.
Pancreatic cancer screening has been hampered by the high rate of complications associated with interrogating the pancreas. The closest non-invasively accessible mucosa available for pancreatic cancer screening is the periampullary duodenal tissue. Our earlier report has shown the potential of using optical markers to interrogate this tissue for the presence of pancreatic cancer. In this study, we report a larger data set of low-coherence enhanced backscattering (LEBS) and elastic light scattering fingerprinting (ELF) optical markers from the periampullary duodenal mucosa. Optical measurements from biopsy samples were acquired from a total of 203 patients with varying clinical classification including healthy controls, a family history of pancreatic cancer, pancreatitis, mucinous cystic precursor lesions, pancreatic cancer, and other pancreatic malignancies. Evaluation of the performance of an independent testing set for discriminating healthy control patients from pancreatic cancer patients showed a 95% sensitivity, 71% specificity, and 85% area under the receiver operator characteristic (AUROC) curve. Importantly, this performance was uncompromised for detecting potentially curable stages of the disease. Additionally, optical markers in higher risk populations such as family history and pancreatitis had values between those of healthy control and pancreatic cancer patients, thus allowing for future investigations of screening from these high risk groups.  相似文献   
73.
The aim of this study was to investigate the possible correlation between the 1H MRS mobile lipid signal, necrosis and lipid droplets in C6 rat glioma. First, the occurrence of necrosis and lipid droplets was determined during tumor development, by a histological analysis performed on 34 rats. Neither necrosis nor lipid droplets were observed before 18 days post-implantation. At later stages of development, both necrosis and lipid droplets were apparent, the lipid droplets being mainly located within the necrotic areas. Using a second group of eight rats, a temporal correlation was evidenced between mobile lipid signal detected by in vivo single-voxel one- (136 ms echo time) and two-dimensional J-resolved 1H MR spectroscopy, and the presence of necrosis and lipid droplets on the histological sections obtained from the brains of the same rats. Finally, spatial distribution of the mobile lipid signal was analyzed by chemical-shift imaging performed on a third group of eight animals, at the end of the tumor growth. The spectroscopic image corresponding to the resonance of mobile lipids had its maximum intensity in the center of the tumor where necrotic regions were observed on the histological sections. These necrotic areas contained large amounts of lipid droplets. All these results suggest that mobile lipids detected in vivo by 1H MRS (136 ms echo time) in C6 rat brain glioma arise mainly from lipid droplets located in necrosis.  相似文献   
74.
To elevate effects of carbon dioxide (CO2) retention by way of an increased respiratory load during submaximal exercise (150 W), the concentration changes of oxy‐ (ΔHbO2) and deoxy‐haemoglobin (ΔHb) of active muscles and the brain were determined by near‐infrared spectroscopy (NIRS) in eight healthy males. During exercise, pulmonary ventilation increased to 33 (28–40) L min–1 (median with range) with no effect of a moderate breathing resistance (reduction of the pneumotach diameter from 30 to 14 and 10 mm). The end‐tidal CO2 pressure (PETCO 2) increased from 45 (42–48) to 48 (46–58) mmHg with a reduction of only 1% in the arterial haemoglobin O2 saturation (SaO 2). During control exercise (normal breathing resistance), muscle and brain ΔHbO2 were not different from the resting levels, and only the leg muscle ΔHb increased (4 (–2–10) μM , P < 0.05). Moderate resistive breathing increased ΔHbO2 of the intercostal and vastus lateralis muscles to 6 ± (–5–14) and 1 (–7–9) μM (P < 0.05), respectively, while muscle ΔHb was not affected. Cerebral ΔHbO2 and ΔHb became elevated to 6 (1–15) and 1 (–1–6) μM by resistive breathing (P < 0.05). Resistive breathing caused an increased concentration of oxygenated haemoglobin in active muscles and in the brain. The results indicate that CO2 influences blood flow to active skeletal muscle although its effect appears to be smaller than for the brain.  相似文献   
75.
Oleoylethanolamide (OEA) is a naturally occurring bioactive lipid belonging to the family of N-acylethanolamides. A variety of beneficial effects have been attributed to OEA, although the greater interest is due to its potential role in the treatment of obesity, fatty liver, and eating-related disorders. To better clarify the mechanism of the antiadipogenic effect of OEA in the liver, using a lipidomic study performed by 1H-NMR, LC-MS/MS and thin-layer chromatography analyses we evaluated the whole lipid composition of rat liver, following a two-week daily treatment of OEA (10 mg kg−1 i.p.). We found that OEA induced a significant reduction in hepatic triacylglycerol (TAG) content and significant changes in sphingolipid composition and ceramidase activity. We associated the antiadipogenic effect of OEA to decreased activity and expression of key enzymes involved in fatty acid and TAG syntheses, such as acetyl-CoA carboxylase, fatty acid synthase, diacylglycerol acyltransferase, and stearoyl-CoA desaturase 1. Moreover, we found that both SREBP-1 and PPARγ protein expression were significantly reduced in the liver of OEA-treated rats. Our findings add significant and important insights into the molecular mechanism of OEA on hepatic adipogenesis, and suggest a possible link between the OEA-induced changes in sphingolipid metabolism and suppression of hepatic TAG level.  相似文献   
76.
77.
曹梦珍  黄倩  牛明  赵旭  肖小河 《中草药》2023,54(10):3150-3157
目的 从鳖甲临床抗肝纤维化功效出发并结合近红外光谱,探索建立关联抗肝纤维化活性的鳖甲质量生物活性评价方法。方法 建立转化生长因子-β1(transforming growth factor-β1,TGF-β1)诱导的LX-2肝纤维化细胞模型,采用qRT-PCR检测鳖甲对I型胶原(type I collagen,COL1)mRNA表达的影响,计算鳖甲对COL1 mRNA相对表达量的抑制率;采用Western blotting检测鳖甲对COL1蛋白表达的影响,以评价鳖甲在细胞模型上的抗肝纤维化生物活性。采集并处理不同批次鳖甲药材的近红外光谱数据,通过谱-效相关分析探究鳖甲药材近红外光谱数据与其抗肝纤维化活性的相关性,筛选活性波段,建立鳖甲的效应近红外谱,以效应近红外谱下面积评价鳖甲药材的质量。结果 体外实验表明,与模型组比较,鳖甲水提物(water extract of Trionycis Carapax,WECT)处理组细胞中COL1 mRNA与蛋白表达水平显著下调(P<0.05、0.01);基于谱-效相关分析,共筛选得到R>0.6、P<0.05且波数大于8 cm−1的活性波段3个,分别为5226~5235 cm−1、5943~6071 cm−1与6379~6396 cm−1,以3个活性波段下面积为指标,建立鳖甲药材的效应近红外谱,计算各特征波段下面积和,并分析其与生物活性的相关性,两者相关系数R为0.813 53。结论 WECT可抑制LX-2细胞外基质的产生来治疗肝纤维化;效应波谱下面积和(5226~5235 cm−1、5943~6071 cm−1与6379~6396 cm−1)作为鳖甲药材的质量评价系数,用于评价鳖甲药材的质量,可区分不同批次鳖甲药材的抗肝纤维化活性。  相似文献   
78.
陈建波  杨乐  刘芬  董玲 《中草药》2023,54(20):6629-6642
目的 建立中药配方颗粒辅料麦芽糊精的检测方法,为中药配方颗粒质量评价提供分析技术支持。方法 建立配方颗粒中果糖、葡萄糖、蔗糖、麦芽糖、乳糖的HPLC定量检测方法,根据样品经糖化酶水解后的葡萄糖增加量换算出麦芽糊精含量。基于中药浸膏与麦芽糊精不同比例混合物的中红外光谱(mid-infrared spectroscopy,MIRS)特征峰差异,建立配方颗粒中麦芽糊精的半定量检测方法。结果 所建立的HPLC方法可以准确定量检测配方颗粒中果糖、葡萄糖、蔗糖、麦芽糖、乳糖。如果中药浸膏自身含有较多可经糖化酶水解产生葡萄糖的成分(淀粉、蔗糖等),HPLC检测配方颗粒中麦芽糊精时存在系统性正误差,可通过中药浸膏酶解后葡萄糖增加量、待测样品酶解后蔗糖减小量等部分修正正误差。如果中药浸膏自身少含或不含淀粉、蔗糖等可经糖化酶水解产生葡萄糖的成分,HPLC检测配方颗粒中麦芽糊精时存在系统性负误差,换算公式偏差、麦芽糊精纯度、样品处理损失等导致根据样品酶解后葡萄糖增加量计算的麦芽糊精“检测含量”预期低于根据生产投料计算的麦芽糊精“名义含量”。麦芽糊精含量越高,配方颗粒MIRS中1200~900 cm-1区域的...  相似文献   
79.
80.
BackgroundAlthough various studies have been conducted to demonstrate the possibility of Raman spectroscopy (RS) as a diagnostic tool for prostate cancer (PC), it is difficult to use it in the real clinical area because of imitations in various research processes. Therefore, we did a systematic review and meta-analysis about the accuracy in diagnostic use of RS for PC.MethodsA literature search was done using PubMed, Embase, and Cochrane library databases in March 2019 to analyze the accuracy of RS for diagnosis of PC. The accuracy of RS for diagnosis of PC was evaluated by means of pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC).ResultsFive studies were included for qualitative analysis by screening the remaining articles according to the inclusion and exclusion criteria by means of a systematic review. The pooled sensitivity and specificity of RS were 0.89 (95% CI: 0.87–0.91) and 0.91 (95% CI: 0.89–0.93), respectively. The overall PLR and NLR were 9.12 (95% CI: 4.15–20.08) and 0.14 (95% CI: 0.07–0.29), respectively. The DOR of RS demonstrated high accuracy (73.32; 95% CI: 18.43–291.73). The area under the curves (AUCs) of SROC curves was 0.93.ConclusionsRS is an optical diagnostic method with high potential for diagnosis and grading of PC and has advantages of real-time and convenient use. In order to consider real-time use of RS in an actual clinical setting, more studies for standardization and generalization of RS performance and analytical method must be conducted.  相似文献   
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