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1.
In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
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目的建立环境水样中痕量铜的浊点萃取(cloud point extraction,CPE)-火焰原子吸收光谱(flame atomic absorption spectrometry,FAAS)测定法。方法样品在p H 9.5的条件下,加入0.4 ml的1 mmol/L 2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)溶液,0.1%氯化钙溶液0.1 ml,5%(W/V)Triton X-114溶液0.8 ml,40℃加热15 min后离心,采用火焰原子吸收光谱法进行检测。结果在2~240μg/L的线性范围内,所得回归方程为A=0.002 7c+0.024 6,r=0.995 8。以3倍信噪比计算,方法的检出限为0.62μg/L,富集倍数为36.58倍,平均加标回收率为96.28%~98.08%,RSD为1.67%~3.13%。结论该方法简单、灵敏,具有良好的重现性,适用于环境水样中痕量铜的测定。 相似文献
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目的:观察黄连解毒汤对重度颅脑损伤合并肺部感染患者血气指标和炎症因子的影响,探讨其治疗效果。方法:随机抽签方式将77例重度颅脑损伤合并肺部感染患者分为两组。对照组35例接受常规治疗,研究组42例在常规治疗基础上,联合黄连解毒汤直肠灌注及全身擦浴治疗。评估两组临床效果,记录两组呼吸机使用时间、ICU入住时间及治疗费用,测定两组治疗前后血气指标和炎症因子。结果:两组临床治疗效果间差异无统计学意义(P>0.05)。与对照组比,研究组呼吸机使用时间和ICU入住时间明显缩短,ICU治疗费用显著减少(P<0.01)。治疗后两组SaO、PaO2水平明显上升,PaCO2及血清PCT、IL-1β、HMGB-1、CRP水平明显下降(P<0.05)。组间比较,研究组SaO、PaO2水平高于对照组,PaCO2及血清PCT、IL-1β、HMGB-1、CRP水平低于对照组(P<0.05)。结论:黄连解毒汤直肠灌注联合全身擦浴可明显控制重度颅脑损伤合并肺部感染患者感染病症,改善血气指标,调节炎症反应,缩短呼吸机使用时间和ICU入住时间,减少患者的治疗费用。 相似文献
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《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action. 相似文献
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《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(2):404-414
Mass spectrometry (MS) is a type of analysis used to determine what molecules make up a sample, based on the mass spectrum that are created by the ions. Mass spectrometers are able to perform traditional target analyte identification and quantitation; however, they may also be used within a clinical setting for the rapid identification of bacteria. The causative agent in sepsis is changed over time, and clinical decisions affecting the management of infections are often based on the outcomes of bacterial identification. Therefore, it is essential that such identifications are performed quickly and interpreted correctly. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometer is one of the most popular MS instruments used in biology, due to its rapid and precise identification of genus and species of an extensive range of Gram-negative and -positive bacteria. Microorganism identification by Mass spectrometry is based on identifying a characteristic spectrum of each species and then matched with a large database within the instrument. The present review gives a contemporary perspective on the challenges and opportunities for bacterial identification as well as a written report of how technological innovation has advanced MS. Future clinical applications will also be addressed, particularly the use of MALDI-TOF MS in the field of microbiology for the identification and the analysis of antibiotic resistance. 相似文献
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目的:分析鼻塞式同步间歇正压通气(NIPPV)联合布地奈德雾化治疗ARDS(新生儿急性呼吸窘迫综合征)疾病的临床应用效果。方法:纳入病例是2017年5月—2019年11月收治的104例ARDS新生儿,随机平均分为两组。参照组52例采纳CPAP(持续气道正压通气通气)治疗,实验组52例采纳NIPPV+布地奈德雾化治疗,对比两组呼吸机通气时间、用氧时间、住院时间、血气指标以及并发症发生情况。结果:实验组呼吸机通气时间、用氧时间、住院时间均明显短于参照组,差异有统计学意义P<0.05;实验组治疗3 d后PaCO2明显低于参照组,实验组治疗3 d后PH以及PaO2明显高于参照组,差异有统计学意义P<0.05;实验组并发症发生率(3.85%,2/52)明显低于参照组(21.15%,11/52),差异有统计学意义P<0.05。结论:NIPPV+布地奈德雾化可有效缩短ARDS患者机械通气时间,改善血气指标,降低并发症发生率,值得借鉴。 相似文献
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Regional fractional ventilation mapping in spontaneously breathing mice using hyperpolarized 129Xe MRI 下载免费PDF全文
Hirohiko Imai Hironobu Matsumoto Erika Miyakoshi Shintaro Okumura Hideaki Fujiwara Atsuomi Kimura 《NMR in biomedicine》2015,28(1):24-29
The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.
《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(2):475-482
Immunoglobulins (Igs) are major serum proteins which play important roles in immunity. Both untargeted and targeted proteomic workflows can be applied to investigate antigen-binding sites and the glycosylation profiles of Igs. For a more-comprehensive picture of IgG from human serum, we developed an IgG purification process and coupled the standardized method to untargeted and targeted proteomic workflows for IgG investigations. Parameters such as the type of purification beads, volume of the bead slurry, incubation conditions, and binding capacities were evaluated in this study. Only 2 μL of human serum was required for each sample. The performance of coupling the purification process to untargeted proteomics in the IgG analysis was evaluated by comparing normalized abundances of IgG subclass-specific peptides with quantification results from an ELISA. Pearson's correlation values were all >0.82. Targeted proteomic workflow was applied to serum samples from patients with autoimmune pancreatitis and from healthy controls, and the results corresponded to clinical findings that IgG4-related peptides/glycopeptides showed higher abundances in the diseased group. The developed IgG purification process is simple and requires small sample volume, and it can be coupled to targeted and untargeted proteomic workflows for clinical investigations in the future. 相似文献