吴茱萸碱抑制胃癌SGC-7901细胞生长及诱导凋亡作用的研究

目的观察吴茱萸碱对胃癌SGC-7901细胞凋亡的生长抑制作用,并探讨可能的分子机制。方法体外培养人胃癌SGC-7901细胞,分别用0.5、1.0、1.5μmol/L吴茱萸碱及吴茱萸碱＋20μmol/L胱天蛋白酶抑制剂（Z-VAD-FMK）作用于SGC-7901细胞12、24和36 h。四唑盐（MTT）比色法观察吴茱萸碱对SGC-7901细胞增殖活性的影响。采用膜联蛋白V-异硫氰酸荧光素/碘化丙啶（Annexin V-FITC/PI）双染细胞,流式细胞仪检测SGC-7901细胞凋亡的情况。结果吴茱萸碱能抑制SGC-7901细胞增殖,MTT结果显示具有时间和剂量的依赖性;流式细胞仪结果显示吴茱萸碱可诱导SGC-7901细胞凋亡,且随剂量和时间的增加作用增强;Z-VAD-FMK可部分抑制吴茱萸碱诱导该细胞的凋亡作用。结论吴茱萸碱能抑制人胃癌SGC-7901细胞增殖并诱导其凋亡,且在加入Z-VAD-FMK后吴茱萸碱仍可诱导其凋亡,但作用减弱。该研究结果提示吴茱萸碱诱导胃癌SGC-7901细胞凋亡除胱天蛋白酶途径外,还存在其他的诱导凋亡途径。     

薯蓣皂苷元对人胃癌SGC-7901细胞体外作用的研究

目的探讨薯蓣皂苷元对人胃癌SGC-7901细胞株的增殖、细胞周期和细胞凋亡的影响。方法采用MTT比色法检测不同浓度薯蓣皂苷元对SGC-7901细胞的增殖抑制作用;采用流式细胞术检测薯蓣皂苷元对SGC-7901细胞凋亡的影响。结果 MTT结果显示,薯蓣皂苷元体外可抑制人胃癌SGC-7901细胞增殖,并呈时间-剂量依赖性,作用244、8、72 h的半数抑制浓度(IC50)分别为62.90、31.83和18.21μg.mL-1;流式细胞检测表明,8、163、2、64μg.mL-1的薯蓣皂苷元分别作用SGC-7901细胞122、43、6 h,对细胞周期没有明显影响,但能明显诱导SGC-7901细胞发生凋亡,同样具有显著的时间-剂量依赖性。结论薯蓣皂苷元具有抑制人胃癌SGC-7901细胞增殖、诱导其凋亡的作用,但对SGC-7901细胞周期没有明显影响。     

藤蟾方抑制人胃癌细胞的生长及诱导其凋亡的实验研究

目的探讨中药复方藤蟾方在体外对人胃癌细胞SGC-7901的生长抑制及凋亡诱导作用.方法用MTT法及流式细胞仪分析法分析藤蟾方对人胃癌细胞SGC-7901细胞的抑制作用及诱导凋亡情况.结果 (1)藤蟾方在3.5μg/ml时显示对人胃癌SGC-7901细胞的抑制作用,并随浓度升高而增强,具有显著性差异(P＜0 01);(2)通过散点图可看出,随浓度的增加右下象限和右上象限出现高染现象,呈剂量依赖性.其中与空白组比较,低、中、高三剂量的凋亡率均有显著性差异(P＜0.01),中、高剂量的坏死率亦有差异(P＜0.01或P＜0.05).结论提示藤蟾方在体外能抑制人胃癌细胞SGC-7901的生长,诱导细胞凋亡,这可能为藤蟾方抑制其生长的机理之一.     

荷包牡丹碱对人胃癌 SGC-7901细胞生长的作用及机制初探

目的探讨荷包牡丹碱对人胃癌SGC-7901细胞生长的抑制作用及其可能的机制。方法体外培养人胃癌SGC-7901细胞,MTT法测定细胞增殖情况;Hoechst33258染色观察细胞凋亡形态学变化;West-ern blot法检测Bax、Bcl-2和Caspase-3的表达。结果 MTT法显示：不同浓度的荷包牡丹碱作用于胃癌SGC-7901细胞不同的时间之后,SGC-7901细胞呈现时间及浓度依赖性的生长抑制;流式细胞仪方法显示：荷包牡丹碱可以促进胃癌SGC-7901细胞的凋亡;行Hoechest33258染色可见细胞核出现固缩、边集,形成凋亡小体等凋亡现象;Western blot法检测显示：与对照组相比,药物作用后Bcl-2表达降低,Bax、Caspase-3表达升高, Bcl-2/Bax比例失调。结论荷包牡丹碱在体外对胃癌细胞的增殖与生长具有抑制作用,可促进其凋亡,其作用可能与Bcl-2/Bax降低导致Caspase-3活化有关。     

β-二氢青蒿素-大黄素复合物对人胃癌细胞株SGC-7901增殖的影响

目的探讨β-二氢青蒿素-大黄素复合物抑制人胃癌SGC-7901细胞增殖,促进其凋亡的作用及机制。方法用MTT比色法检测β-二氢青蒿素-大黄素复合物对SGC-7901细胞的抗增殖及细胞毒作用;利用流式细胞仪分析复合物作用前后SGC-7901细胞周期分布及凋亡率的改变;应用免疫细胞化学染色法检测蛋白CyclinD1和Ki-67的表达变化。结果 (1)MTT结果显示,β-二氢青蒿素-大黄素复合物对SGC-7901细胞抑制作用显著,且呈浓度-时间依赖性(P0.05);(2)流式细胞仪检测分析出:实验组的细胞增殖被阻滞于G0/G1期、且凋亡率升高,均呈浓度梯度趋势(P0.05);(3)免疫细胞化学染色结果显示:实验组中Ki-67和CyclinD1的阳性表达率明显降低,且具有浓度依赖性(P0.05)。结论β-二氢青蒿素-大黄素复合物可以抑制人胃癌SGC-7901细胞的增殖,促进其凋亡,并且呈时效和量效关系;其作用机制可能与影响细胞周期有关,且药物浓度越高,下调作用越明显。     

β-咔啉类生物碱对人胃癌细胞SGC-7901增殖的影响

目的 探讨β-咔啉类生物碱对人胃癌细胞SGC-7901增殖的影响。方法 通过体外培养人胃癌细胞株SGC-7901,将含有不同浓度(5、10、20、40μg/mL)β-咔啉类生物碱的培养液与SGC-7901细胞共同培养24 h和48 h。采用MTT比色法计算细胞抑制率;在荧光显微镜下用Hoechst 33258细胞核染色法观察细胞形态学改变;流式细胞仪检测凋亡率及基因组DNA琼脂凝胶电泳检测凋亡梯状条带。结果 β-咔啉类生物碱对SGC-7901细胞的损伤呈浓度依赖性;β-咔啉类生物碱分别作用24 h和48 h后半数抑制浓度(IC50)分别为17.79μg/mL和12.17μg/mL;荧光染色可观察到有细胞核固缩及核断裂的凋亡现象;流式细胞术显示:阴性对照组(0μg/mL)及β-咔啉类生物碱5、10、20、40μg/mL浓度组24、48 h凋亡率为别1.66%、11.27%、20.32%、30.66%、41.42%和3.84%、15.29%、23.34%、34.87%、49.54%,细胞凋亡率伴随给药浓度增加而增加;基因组DNA琼脂糖凝胶电泳检测到明显的凋亡梯状条带。结论 β-咔啉类生物碱能诱导人胃癌SGC-7901细胞发生凋亡,抑制细胞增殖。     

连翘提取物LQ-4对SGC-7901胃癌细胞体外促凋亡作用研究

目的观察连翘提取物LQ-4对SGC-7901胃癌细胞体外促凋亡作用,为LQ-4在抗肿瘤机制研究及应用提供理论依据。方法应用MTT法测定LQ-4对SGC-7901胃癌细胞增殖的抑制作用;采用AO-EB染色、透射电镜、流式细胞仪检测其促凋亡作用。结果 LQ-4对SGC-7901胃癌细胞体外增殖抑制呈明显的剂量时间依赖性,LQ-4处理细胞6、12、24h后的半数抑制浓度(IC50)分别为(73.27±3.19)μg/ml、(44.63±2.06)μg/ml、(35.99±2.43)μg/ml,各组间差异有统计学意义,F=15.25(P<0.01);AO-EB染色表明药物组细胞出现明显凋亡,阴性对照组细胞形态完好;透射电镜表明,SGC-7901胃癌细胞在LQ-4处理后出现典型凋亡细胞形态改变;FCM分析结果表明,SGC-7901胃癌细胞在LQ-4处理前后细胞凋亡率发生改变,其中溶媒对照组为(0.73±0.49)%,25、50、100μg/mlLQ-4作用组分别为(8.04±0.68)%、(18.45±0.83)%、(52.37±0.74)%,各组间差异有统计学意义,F=13.17(P<0.05)。结论连翘提取物LQ-...     

康莱特对胃癌细胞增殖及凋亡能力的影响

目的 通过观察不同浓度康莱特对胃癌细胞株SGC-7901增殖及凋亡能力的影响作用,探讨康莱特的抗胃癌作用机制.方法 以不同浓度康莱特作用SGC-7901细胞,CCK-8检测细胞增殖抑制率,流式细胞术检测细胞凋亡率和细胞周期,酶联免疫吸附法(ELISA法)检测细胞内凋亡蛋白Bcl-2的变化.结果 5～15μK/ML康莱特可抑制SGC-7901细胞增殖并诱导其凋亡,其抑制及诱导凋亡效应呈浓度-时间依赖性;细胞周期分析处于G1期细胞百分比明显增多,处于G2/M期的细胞减少;Bcl-2表达下调.结果 康莱特能抑制胃癌SGc-7901细胞增殖或诱导其凋亡,且其机制可能与通过下调Bcl-2的表达有关.     

选择性COX-2抑制剂NS-398对人胃腺癌细胞增殖和凋亡的影响

目的通过COX-2抑制剂NS-398对胃癌培养细胞系SGC7901增殖及凋亡影响的研究证实非甾体类抗炎药（NSAID。）可在体外抑制胃癌细胞的生长。方法应用MTT法检测NS-398对胃癌细胞SGC7901细胞增殖的影响；应用流式细胞仪、透射电镜检测NS-398对胃癌细胞SGC7901细胞凋亡的影响。结果MTT结果显示NS-398对胃癌细胞均抑制作用，并随剂量的增加及作用时间延长，其抑制作用要明显增加；透射电镜观察发现未经NS-398作用的胃癌培养细胞的细胞核和细胞器亚微结构清晰，核模完整，而经不同浓度的舒林酸和尼美舒利作用后细胞呈现典型的凋亡形态学变化，并可见凋亡小体形成；流式细胞仪结果显示不同浓度的NS-398作用SGC7901细胞72h后，均可出现亚G1峰，呈剂量依赖关系诱导胃癌细胞凋亡，并呈浓度依赖性改变的细胞周期分布，一方面增高G0／G期细胞比例，另一方面降低S期和G2／M期细胞比例。结论NS-398可抑制胃癌SGC7901细胞的增殖；NS-398促进胃癌SGC7901细胞的凋亡；NS-398抑制胃癌的机制可能是通过抑制胃癌细胞COX-2的活性，从而抑制前列腺素E2的释放而抑制胃癌细胞的生长。     

尼美舒利对丝裂霉素-c抑制人胃癌细胞株细胞增殖及诱导凋亡影响的实验研究

目的 研究环氧化酶-2(Cyclooxygenase-2，COX-2)选择性抑制剂尼美舒利(Nimesulide，NIM)对丝裂霉素-c(Mitomycin，MMC-c)抑制体外培养人胃癌细胞株SGC7901及MGC803细胞增殖及诱导凋亡作用的影响。方法 采用MTT比色法观察NIM对MMC-c抑制人胃癌细胞SGC7901及MGC803细胞增殖的影响；采用流式细胞仪技术及吖啶橙荧光染色观察NIM对MMC-c诱导人胃癌细胞SGC7901及MGC803细胞凋亡的影响。结果 NIM能增强MMC-c抑制SGC7901细胞增殖及诱导SGC7901细胞凋亡，而对MGC803细胞无明显影响。结论 COX-2选择性抑制剂NIM能增强MMC-c对部分人胃癌细胞抑制增殖与诱导凋亡作用，作用有无可能取决于癌细胞COX-2的表达情况。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.