Notch配体Delta-1ike1对小鼠骨髓细胞来源的树突状细胞分化和抗原呈递功能的影响

本研究探讨Notch配体Delta—likel（Dil1）对小鼠骨髓细胞来源的树突状细胞（dendriticcell,DC）分化及其抗原呈递功能的影响。在GM—CSF和IL4存在条件下,用OP9-Dil1和OPt）．GFP细胞分别与小鼠骨髓细胞共培养8天,经肿瘤抗原刺激成熟。用流式细胞仪检测DC表面MHCII、CD80和CD86的表达情况,ELISA法检测肿瘤抗原刺激后DC培养上清细胞因子IL-12和IL110的水平,通过混合T淋巴细胞反应观察DC对T细胞的促增殖能力。结果表明：与GFP组相比,Dll1组的小鼠骨髓来源的树突状细胞明显增多（P〈0．05）。肿瘤抗原刺激后,Dll1组DC表面MHCII、CD80和CD86表达量更高。DC分泌的IL-12水平显著高于对照组（P〈0．05）,而IL-10的水平显著低于对照组（P〈0．01）。Dll1组DC具有更强的促T细胞增殖活性。结论：OP9-Dll1促进小鼠骨髓细胞向DC分化并增强其抗原呈递功能。     

慢性乙型肝炎患者外周血单个核细胞 IFN-γ、IL-6水平变化与拉米夫定疗效的关系

目的 探讨慢性乙型肝炎（CHB）患者拉米夫定治疗前后外周血单个核细胞（PBMC）产生干扰素-1（IFN-γ）、白细胞介素-6（IL-6）水平与血清乙型肝炎病毒（HBV）载量和丙氨酸氨基转移酶（ALT）的关系。方法 采用荧光定量聚合酶链反应（FQ-PCR）和酶联免疫吸附试验（ELISA）分别检测拉米夫定治疗前后的CHB患者HBVDNA和PBMC经植物血凝素（PHA）刺激后分泌IFN-1和IL-6的水平。结果 CHB患者治疗前PBMC分泌IFN-1水平显著低于正常对照组（P〈0，01），分泌IL-6水平显著高于正常对照组（P〈0．01）；拉米夫定治疗后HBV高、中载量组分泌IFN-1较治疗前显著升高（分别为P〈0．0l和P〈0，05），分泌IL-6水平较治疗前显著降低（分别为P〈0，01和P〈0，05），治疗后中、低载量组分泌IFN-1水平仍低于正常对照组（P〈0，01），中、低载量组分泌IL-6的水平高于正常对照组（P〈0．01）；患者INF．1水平变化与HBVDNA载量呈负相关（r=0，89，P〈0．001），IL-6水平变化与HBVDNA载量和A胛呈正相关（分别为r=0．92，P〈0，001；r=0．74，P〈0．001）。结论 CHB患者PBMC分泌IFN-1、IL-6水平可作为判断拉米夫定治疗效果的参考指标。     

rhG-CSF对健康供者外周血和骨髓免疫特性影响的比较

本研究探讨rhG—CSF对健康供者外周血采集物（G—PB）和骨髓采集物（G—BM）免疫学特性影响的异同。用MTT法和夹心酶联免疫复合物（ELISA）法检测G—PB和G—BM中T淋巴细胞增殖能力和IL-4、IFN-7的分泌，并用流式细胞术测定两种移植物的T细胞亚群、树突状细胞（DC）亚群、单核细胞及共刺激分子CD28的表达。结果表明：G—PB中淋巴细胞，CD3^＋、CD4^＋、CD8^＋T淋巴细胞，DC1、DC2以及单核细胞的含量，CD4／CD8的比值高于G—BM（P〈0，001）。G—PB的T淋巴细胞增殖能力高于G—BM（P〈0．05）；每微升G—PB移植物中T淋巴细胞分泌细胞因子IFN-γ,IL-4的量均明显高于G—BM，且G—PB中IL-4／IFN-γ比值小于G-BM（P〈0．001），DC2与T淋巴细胞的比值也低于G—BM（P〈0．01）；而G-PB中CD4^＋、CD8^＋细胞上CD28表达的百分比和总体表达均高于G—BM（P〈0．001）。结论：rhG—CSF体内应用诱导G—PB和G—BM产生的T细胞免疫低反应性是有差异的，而两者之间的差异是G—PB和G—BM移植后移植物抗宿主病（GVHD）发生率和程度不同的免疫学基础。     

树突状细胞吞噬经光化学处理的异基因细胞后对同基因T细胞的免疫调控

本研究探讨树突状细胞（DC）吞噬经PuVA（8-methoxypsoralen plus UVA irradiation,8-甲氧基补骨脂素联合长波紫外线照射的体外光化学治疗）处理的同种异基因淋巴细胞后对于同基因T细胞的免疫调控作用。分离LEW大鼠骨髓细胞,经几4和GM—CSF共同诱导制备骨髓来源的LEW大鼠DC。分离DA大鼠脾淋巴细胞（SP）,制备经PUVA处理的DA大鼠脾淋巴细胞（PUVA—SP）,检测NJvA—sP的凋亡率。在体外将PUVA—SP或sP与受者骨髓来源的未成熟DC共同培养,检测上述处理对受者DC表面分子CD40、CD86、MHC—Ⅱ的影响。以cFsE标记PUVA—SP,通过荧光显微镜观察LEW大鼠DC吞噬DA大鼠PuVA—sP的情况。通过混合淋巴细胞培养（MLR）,检测吞噬DA大鼠PUVA—SP的LEW大鼠DC（PUVA—sPDC）对LEW大鼠T细胞的刺激作用,同时检测MLR培养上清中细胞因子1L-4、IL-10、IL-2、IFN-1,的浓度。结果表明：PUVA处理能够在24小时内诱导62．87％的DA大鼠脾淋巴细胞发生早期凋亡。LEW大鼠DC与DA大鼠PUVA—SP共培养后,可有效吞噬PUVA—SP。LEW大鼠DC与DA大鼠sP混合培养后,其表面分子MHc-Ⅱ、CD40以及CD86的表达阳性率分别为65．6％、45．6％和36．5％,明显高于未经处理的受者DC组27．7％、22．9％和13．0％（P〈0．01）;而DC与PUVA—SP混合培养后,其表面分子MHc—Ⅱ、CD40及cD86的表达仍保持较低的水平,分别为25．7％、21．0％和13．4％,与未经任何处理的对照组DC相当（P〉0．05）,而远远低于LPS刺激后的成熟DC（82．3％、71．7％和63．2％）（P〈0．01）。DA大鼠SP共培养后的LEW大鼠DC可以刺激LEW大鼠T细胞显著增殖,刺激指数在加载DC数量为2×10^3、10×10^3、20×10^3组分别为1．7546、3．9798和5．0220,而吞噬DA大鼠PUVA—SP的LEW大鼠DC则诱导了T淋巴细胞低反应性,刺激指数分别为1．0120、1．1518和1．4093,二者差异有统计学意义（P〈0．01）。此外,与SPDc相比,PUVA—SPDC明显抑制了T细胞IFN-γ的分泌（140．17±2．28VS37．67±1．76）（P〈0．01）,刺激了IL--10（33．11±1．82VS69．58±1．83）（P〈0．01）、IL-4的分泌（11．11±1．07VS23．83±0．73）（P〈0．01）,但对IL-2的分泌没有抑制作用（428．18±4．55VS423．86±5．39）（p〉0．05）。结论：PUVA-sP DC能够诱导大鼠T细胞对异基因抗原的免疫低反应,还可在体外诱导LEW大鼠T淋巴细胞由Th1向Th2免疫偏移。     

硒与树突状细胞对T细胞杀伤白血病细胞活力的影响

本研究探讨经亚硒酸钠（Na2SeO3）处理、K562细胞裂解物冲击致敏的外周血衍生的树突状细胞（DC）的生物学特性和体外诱导抗原特异性细胞毒性T淋巴细胞（CTL）应答的能力。健康人外周血单个核细胞（PBMNC）于体外在含3种细胞因子（rhGM—CSF、rhIL-4、TNF-α）的RPMI1640＋10％FBS培养液中培养4天，收获贴壁细胞，实验分4组：DCⅠ组：仅含DC；DCⅡ组：DC＋Se（0．5μmol／L）；DCⅢ组：DC＋K562细胞裂解液；DCⅣ组：在DCⅢ组中加入Se（0．5μmol／L）。在培养的第7天于倒置显微镜下进行活细胞观察。用流式细胞术（FCM）检测细胞表型CD1a、CD40、CD83、CD86。乳酸脱氢酶（LDH）释放试验检测CTL效应。用酶联免疫吸附试验（ELISA）测定IL-12含量。结果表明：各组DC均具有典型树突状细胞形态，均较培养前集落增多。DCⅠ组和DCⅡ组的细胞形态及数量无明显差异，DCⅢ组和DCⅣ组的细胞集落数量增加，悬浮细胞比例增加。各组DC细胞的CD1a、CD40、CD83、CD86表达率较PBMNC明显增高（P〈0．01），各组间DC细胞的CD1a和CD40的表达率无明显差异，DCⅢ组和DCⅣ组的CD83和CD86的表达率均高于DCⅠ组和DCⅡ组（P〈0.01），DCⅠ和DCⅡ以及DCⅢ和DCⅣ两组之间CD83和CD86表达率均无明显差异。在效靶比例为25：1时，各组DC致敏的T淋巴细胞对K562细胞的杀伤率为15．3±2．3％、26．3±3．7％、28．2±4.5％和36．2±3．7％，均明显高于未经DC致敏的单独T淋巴细胞组（5．9±2．4％）（P〈0．01），DCⅣ组的CTL效应最强，高于DCⅠ、Ⅱ、Ⅲ组（P〈0．01），DCⅡ和DCⅢ组的CTL效应也高于DCⅠ组（P〈0．01），而DCⅡ和DCⅢ两组间CTL效应程度无明显差异（P〉0.05）；各组DC与T淋巴细胞共培养的上清液中IL-12水平为256．96±64．2、328．12±43.9、322．98±53．5和353.85±46．2pg／ml，均显著高于未经DC致敏的单独T淋巴细胞组（35?     

前S1蛋白阳性慢性乙型肝炎患者外周血中树突状细胞功能的研究

目的研究前S1（preS1）蛋白阳性慢性乙型肝炎（CHB）患者外周血中树突状细胞（DC）的免疫功能。方法分别从正常健康人（10例，对照组1）、preS1蛋白阴性CHB患者（10例，对照组2）和preS1蛋白阳性CHB患者（10例，实验组）外周血中分离出单核细胞（Mo），然后将Mo与GM-CSF，IL-4体外培养12d，并于培养第6d加入IFN-γ共同培养，用MTT法测定DC刺激同种异体T细胞增殖的能力，用ELISA检测DC培养上清中TNF-a和IL-12 p40＋p70的含量，并与对照组比较。结果preS1蛋白阳性CHB患者组DC刺激同种异体T细胞增殖的能力，培养上清中TNF-—a和IL-12 p40＋p70的含量，均明显低于正常健康对照组（P〈0．01）；而与preS1蛋白阴性对照组相比则无明显差异（P〉0．05）。结论CHB患者外周血DC的免疫功能低下；在CHB患者HBV持续感染时期，其外周血DC的功能状态与PreS1阳性与否无直接相关性。     

高强度聚焦超声制备肿瘤抗原致敏树突状细胞及其体外诱导T细胞产生IFN-γ的研究

目的 探讨采用高强度聚焦超声（HIFU）辐照肿瘤细胞制备肿瘤抗原致敏树突状细胞（DD）和制备DD肿瘤疫苗的可行性。方法 （1）采用1ng／ml IL-4和10ng/ml GM-CSF联合诱导小鼠骨髓细胞产生DC，并用流式细胞仪检测DC的CD80、CD86、H-2K^d和I-A^d表达情况；（2）固定辐照时间或超声声强，应用不同声强或辐照时间的HIFU辐照CT26细胞株后，用台盼蓝染色、MTT法检测活肿瘤细胞数，同时用台盼蓝染色观察肿瘤细胞的形态学变化，分析HIFU剂量与肿瘤细胞存活率的关系，了解剂量-效应关系；（3）固定辐照时间和超声强度，HIFU辐照CT26细胞悬液，制备肿瘤细胞抗原并致敏DC，致敏DC与T细胞共孵育48h后提取上清液，通过ELISA法检测上清中IL-12、γ干扰素（IFN-γ）的含量，并与冻融组、单纯CT26、对照组进行比较。结果 （1）采用IL-4和GM-CSF联合诱导小鼠骨髓细胞可培养出典型的DC；（2）固定辐照时间，随着HIFU辐照剂量的增加肿瘤细胞的存活率迅速减少，肿瘤细胞的碎片逐渐增多，当声强为1000W／cm^2，辐照30s时，无细胞存活，肿瘤细胞失去正常形态，全部被撕裂成碎片；（3）通过ELISA法检测HIFU、冻融及单纯CT26组上清液中IL-12、IFN-γ的含量显著高于对照组（P均〈0．05），HIFU及冻融组上清液中IL-12、IFN-γ的含量高于单纯CT26组（P均〈0．05），但HIFU、冻融组之间比较差异无统计学意义（P〉0．05）。结论 HIFU能灭活肿瘤细胞并能使肿瘤细胞破碎，HIFU制备的肿瘤抗原可体外致敏DC，并可使DC成熟分泌大量IL-12，同时诱导T细胞分泌大量IFN-γ。     

霉酚酸对小鼠树突状细胞体外成熟和免疫功能的影响

霉酚酸酯(mycophenolate mofetil，MMF)是一种新型免疫抑制剂，目前已被临床上广泛应用于异基因骨髓移植。本研究的目的是观察其免疫活性成分霉酚酸(mycophenolic acid MPA)对小鼠树突状细胞(dendritic cell，DC)体外成熟和免疫学功能的影响，以期进一步探讨MPA防治移植物抗宿主病(graft versus host disease，GVHD)免疫抑制作用的机理。在小鼠DC体外培养时加入两种剂量(0．01μmol／L和0．1μmol/L)的MPA处理，观察DC的生成情况，以流式细胞仪分析各处理组细胞的免疫表型，以^3H-TdR掺入值来反映DC的抗原呈递功能，并作体外混合淋巴细胞反应观察其对同种T细胞的刺激增殖能力，用ELISA方法测定其分泌的IL-12水平及与同种T细胞共同培养时IL-2，IFN-γ，IL-4和IL-10等细胞因子水平。结果表明：经MPA培养后，DC的生成和形态没有影响，表达低水平的共刺激分子CD40，CD80和CD86，其分泌的IL-12水平明显下降，DC的抗原呈递功能和刺激同种T细胞的功能显著下降，并促使T细胞分泌的Th1细胞因子IL-2和IFN-γ下降，而Th2细胞因子IL-4，IL-10上升。结论：霉酚酸能使小鼠骨髓来源的树突状细胞停留在未成熟状态，对其免疫学功能起负性调节作用，并促使Th1细胞因子向Th2细胞因子转移。     

MUCl模拟表位肽对表达人MUCl T739小鼠膀胱癌细胞的细胞毒作用的实验研究

目的观察MUCl模拟表位肽对表达人MUClT739小鼠膀胱癌细胞的细胞毒作用。方法培养、诱导T739小鼠骨髓成熟树突状细胞,流式细胞仪鉴定纯度,用负载模拟表位肽成熟树突状细胞免疫T739小鼠,酶联免疫斑点（ELISPOT）检测活化的模拟表位特异性T细胞,用非放射性乳酸脱氢酶法检测不同效：靶比例时活化的模拟表位特异性T细胞体外细胞毒效应。结果培养出成熟树突状细胞,纯度为78．8％,肽免疫的T739小鼠特异性分泌IFN-1的T细胞频数是106．5±12．8,而PBS和DC＋PBS组频数均少于l0,数量明显少于肽＋DC组。当效靶比为100：1时肽免疫的T739小鼠产生的活化T淋巴细胞具有显著细胞毒功能,与PBS和DC＋PBS免疫小鼠相比,差异有统计学意义（P〈0．01）。结论负载MUCl模拟表位肽的树突状细胞免疫小鼠,可诱导产生特异性细胞毒性T细胞。     

白介素21对树突状细胞诱导的CTL抗白血病作用的影响

本研究探讨白介素21（IL-21）对树突状细胞（DC）诱导的CTL抗白血病的体外作用。以不同细胞因子诱导培养急性白血病（AL）患者缓解期外周血单个核细胞产生DC，自体AL细胞RNA作为抗原负载DC，与自体T淋巴细胞共培养诱导白血病特异性CTL产生；用LDH释放法检测CTL杀伤自体AL细胞的作用，并检测CTL产生IFN-γ和TNF-α的变化。实验共分2组：实验组，在DC—CTL共培养过程中加用IL-21（200ng／ml）；对照组，不加IL-21。同时对IL-21单独作用培养后成熟DC，检测其表面抗原表达变化以及诱导同种混合淋巴细胞反应能力。结果表明：对照组和实验组的CTL产生率分别为：（56．73±10．21）％，（73．43±18．01）％（P〈0．01）；培养上清中IFN-γ和TNF-α分别为：（154．91±67．20）ng／L，（310．62±141．15）ng／L（p〈0．01）和（8．77±5．09）μg/L，（15．25±6．56）μg／L（p〈0．01）。在效靶比为20：1时，两组对自体AL细胞的杀伤作用分别为（50．22±5．07）％，（75．38±9．47）％（P〈0．01）；IL-21作用后的成熟DC的CD1a、CD83、CD86、CD80和HLA—DR表达没有明显变化；诱导同种混合淋巴细胞反应能力亦没有明显不同。结论：IL-21可促进DC诱导的CTL增殖、增加IFN--γ和TNF—α产生从而增强其抗白血病作用；IL-21对成熟DC表面抗原表达及其免疫功能无明显影响；提示IL-21在白血病免疫治疗中发挥一定的作用，具有潜在的临床应用价值。     

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.