近红外光谱法快速测定当归中7种成分的含量

目的应用近红外光谱(NIRS)技术结合偏最小二乘法(PLS)建立当归中多指标成分的快速无损检测方法,以更好地控制当归药材和饮片的质量。方法采集购买不同产地的当归样品共108批。建立同时测定当归中7种成分含量的超高效液相色谱(UPLC)方法,并以其测定值为参比;以积分球漫反射模式采集当归样品的NIRS图;采用PLS等化学计量学手段建立各指标性成分的参比值与NIRS图的定量校正模型。分别对建模过程的各个阶段进行优化,包括样本集的选择、不同预处理方法和不同光谱区段的选择。结果所建立的绿原酸、阿魏酸、异绿原酸A、藁本内酯、丁烯基苯肽、洋川芎内酯I和欧当归内酯A的模型校正集相关系数分别为0.937 6、0.970 2、0.963 4、0.991 1、0.962 4、0.966 6和0.947 6;预测均方差分别为0.072 1、0.038 9、0.011 3、0.483 0、0.017 5、0.178 0和0.097 0。NIRS模型预测值与UPLC测定值具有良好的线性相关关系,模型预测效果良好。结论采用NIRS技术结合PLS可以快速对当归中绿原酸、阿魏酸、异绿原酸A、藁本内酯、丁烯基苯肽、洋川芎内酯I和欧当归内酯A 7种成分的含量进行检测,方法操作简便、结果可靠。     

超声引导下mammotome微创旋切在乳腺不可扪及肿块切除中的应用

目的：探讨B超定位引导下mammotome切除乳腺不可扪及肿物的临床价值。方法：使用B超高频探头,对37位女性40个临床检查触不及的乳腺肿物作术前体表定位,按定位对40个肿物行麦默通切除术。结果：40个肿物皆被准确切除,病理结果为导管内癌3例,多发性乳头状瘤3例,非典型增生10例,纤维瘤8例,纤维囊性乳腺病伴瘤样增生结节13例,正常乳腺组织3例。结论：B超引导麦默通对不可扪及阴性乳腺肿物切除准确,方便,美观,可用于乳腺体表不可扪及肿块早诊断和治疗。     

中国乳腺癌专病队列研究：人群队列研究方法及基线特征

目的 乳腺癌在女性癌症中发病率第一且逐年上升。2016年9月,国家重点研发计划精准医学研究中国乳腺癌专病队列项目启动,旨在整合队列资源、提高随访质量、构建标准共享的乳腺癌专病队列,为实现乳腺癌发现、预防、早诊、治疗及预后研判等提供研究基础与标准化数据共享平台。方法 本研究基于社区人群,采用询问调查、身体测量、生物样本采集、乳腺超声和钼靶X线检查建立前瞻性队列,采用区域健康监测和定向监测随访队列。结果 整合乳腺癌专病社区人群队列112 118人,其中完成55 419人标准化队列调查,54 304人采集生物样本。平均年龄51.7岁,超重/肥胖女性占62.7%,绝经女性占48.9%。结论 本研究将为中国女性乳腺癌精准防治提供队列基础和研究平台。     

模拟失重雌雄大鼠骨密度、骨代谢指标与骨折风险的相关性

 目的 分析模拟失重雌、雄性大鼠模型骨密度及骨代谢生化指标和生物力学之间的相关性,与骨折风险建立联系,探讨航天医疗基础工作。方法 3个月龄雌、雄性SD大鼠各20只,按照性别及是否失重分为4组。采用尾部悬吊模拟失重方法,实验4周后处死SD大鼠,双能X线吸收法(dual-energy X-ray absorption, DEXA)测定L₄椎体、股骨髁部骨密度,骨组织切片染色,ELISA法检测骨代谢生化标志物:骨碱性磷酸酶(bone alkaline phosphatase,BALP)、抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP),生物力学测试骨强度。结果 悬吊组大鼠较对照组大鼠BMD均显著下降,雌性悬吊组较雄性组下降明显;组织切片悬吊组较对照组骨组织及骨细胞间隙明显增宽,细胞肿胀;BALP、TRAP雄性悬吊组分别较对照组升高3.09和1.72倍,雌性悬吊组分别较对照组升高3.43和2.14倍;悬吊组椎体的最大压缩载荷(N)、最大压缩压力(MPa)、股骨最大抗弯曲载荷(N)悬吊组较对照组显著下降。骨密度(bone mineral density,BMD)、BALP、TRAP与椎体最大力学强度Fmax相关性系数r值,雄性组分别为0.985、-0.949、-0.970,雌性组分别为0.908、-0.858、-0.921。结论 失重4周后大鼠出现明显的骨质疏松、骨小梁结构破坏、力学强度显著下降。雌性大鼠骨质疏松较雄性组明显加重。最大力学强度Fmax与骨密度成正相关,与BALP、TRAP成负相关,未来精准、便捷的骨代谢指标可能成为航天医学预测骨折风险的手段之一。     

催产素对妊娠末期大鼠蜕膜细胞内游离钙的刺激作用

妊娠末期催产素刺激子宫蜕膜细胞产生与分娩有关的前列腺素,但其作用方式仍未知。本实验分离妊娠19d大鼠蜕膜细胞,测定了催产素作用后蜕膜细胞内游离钙的变化,结果加入0.001～1μmol·L^-1催产素后,蜕膜细胞内[Ca²⁺]i出现瞬息增加,其峰值与催产素浓度呈剂量依赖关系,且此作用有自身钝化现象。说明催产素可能激活妊娠末期大鼠蜕膜细胞内的肌醇磷酯蛋白激酶C系统。给妊娠末期大鼠ip硫酸去氢表雄酮钠盐后分离的蜕膜细胞,催产素作用引起[Ca²⁺]i瞬息增加峰值较对照升高。     

离心机模拟连续推拉动作训练方法研究

目的建立贴近实战化训练模式的连续推拉动作(PPM)离心机训练方法。方法调研提炼飞行训练中典型的PPM载荷参数,编制离心机模拟连续PPM曲线。16名战斗机飞行员作为志愿者,A组6名,采用-1Gz/3s→+6Gz/10s→2Gz/10s→0Gz/3s→+4.5Gz/10s→2Gz/10s→0.5Gz/3s→+5 Gz/10s连续PPM曲线,B组10名,采用-1Gz/3s→+6Gz/10s→2Gz/10s→0Gz/3s→+4.5Gz/10s→2Gz/10s→-1Gz/3s→+7Gz/5s连续PPM曲线(根据A组建议对曲线进行了改进),进行了HP动作对抗连续PPM离心机训练。志愿者在相对-Gz(小于+1Gz)暴露时采用HP动作的呼吸方式,在向+Gz转换时开始做较用力的HP动作,记录分析+Gz耐力、心率(HR)等指标的变化。结果A组6名志愿者均完成了连续PPM离心机训练,对PPM曲线提出了改进建议。B组9名志愿者采用改进的连续PPM曲线完成离心机训练。两组在相对-Gz时的HR均显著高于安静状态(P<0.05),连续PPM暴露时的HR变化趋势说明心血管调节有持续效应,其适应负荷有滞后。结论建立了高性能战斗机飞行员连续PPM离心机训练方法,模拟连续PPM曲线中不同水平-Gz与+Gz交替作用的模式更能体现实战化训练中长时间反复空战的特点,将应用于后续飞行员离心机训练。     

Expression of fibrinogen receptors during activation and subsequent desensitization of human platelets by epinephrine

Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine.     

Chlorambucil therapy in hairy cell leukemia: effects on lipid composition and lymphocyte subpopulations

Two patients with progressive hairy cell leukemia following splenectomy were treated with low-dose daily chlorambucil. Both had an objective hematologic response as determined by a return to normal hematocrit and platelet count. This was also reflected in the mononuclear cell fraction by the normalization of cholesterol content, cholesterol/phospholipid ratio, and the lymphocyte subpopulations. This article confirms previous reports on the efficacy of chlorambucil in this setting and describes some morphological, and biochemical concomitant events.     

不同巴曲酶治疗时间窗对急性脑梗死患者脑血管储备的影响

目的 探讨不同时间窗使用巴曲酶治疗急性脑梗死患者对脑血管储备(CVR)的影响.方法 根据发病时间以及治疗方法,123例急性脑梗塞患者分为对照A组(29例,发病12 h以内开始常规治疗)、对照组B组(33例,发病12 h以后开始常规治疗)、治疗A组(29例,发病12 h内常规治疗基础上加用巴曲酶)、治疗B组(32例,发病12 h以后常规治疗基础上加用巴曲酶).对比4组患者治疗前后斯堪地那维亚卒中量表(SSS)评分、大脑中动脉平均血流流速增加值(MFV1-MFV0)、CVR、动脉指数(PI)及两治疗组治疗前后各指标的变化量Δ(MFV1-MFV0)、ΔCVR、ΔPI.结果 治疗后4组患者SSS评分、MFV1-MFV0及CVR较治疗前均升高(P<0.05),PI值较治疗前降低(P<0.05);治疗A、B组治疗后上述指标均优于相应对照组(P<0.05);治疗A组Δ(MFV1-MFV0)、ΔCVR、ΔPI高于治疗B组相应指标(P<0.05).结论 巴曲酶对急性脑梗死患者有显著疗效,能改善患者CVR.早期使用巴曲酶对急性脑梗死患者CVR功能改善作用较为显著,随着时间的推移,疗效降低.     

Trastuzumab-induced cardiotoxicity in elderly women with HER-2-positive breast cancer: a meta-analysis of real-world data

Background: We conducted a meta-analysis to assess the overall risk of cardiac toxicity associated with trastuzumab treatment in elderly breast cancer patients.

Methods: We searched databases from PubMed, EMBASE and Cochrane Central Registry of Controlled Trials to identify relevant studies. Statistical analyses were conducted to calculate the incidence rate, overall hazard ratio (HR) and 95% CIs using a fixed effects model.

Results: A total of 116,342 and 360 elderly patients from five cohort studies and two randomized clinical trials (RCTs) were included for analysis. The pooled incidences of symptomatic congestive heart failure (CHF) and CHF/HF/CM were 6.4% (95% CI 4.1% – 9.4) and 16.4% (95% CI 16.19% – 16.61) in patients with median age of 67.5 years from two RCTs and in patients with median age of 67.5 (60 – 75), 71 (66 – 80+), 74.5 (65 – 89), 75 (66 – 81+) and 79.5 (60 – 99) from five cohort studies, respectively. Trastuzumab was significantly correlated with an increased risk of defined cardiac toxicities in five cohort studies (HR = 1.89, 95% CI 1.72 – 2.07, p < 0.00001) and two RCTs (HR = 3.00, 95% CI 1.71, 5.26, p < 0.00001). Sub-group analysis showed that the anthracycline-based chemotherapy increased the risk of CHF/HF and CM in patients among five cohort studies (HR = 2.16, 95% CI: 1.8 – 1.87, p < 0.00001).

Conclusion: Trastuzumab is likely associated with an increased risk of cardiac toxicity in elderly patients with HER-2-positive breast cancer. Carefully monitoring cardiac function in elderly patients receiving trastuzumab, particularly with concurrent use of anthracycline, is warranted.