主动呼吸控制技术用于原发性肝癌放疗的可行性及剂量学研究

目的研究主动呼吸控制技术(ABC)用于原发性肝癌放疗的可行性并且与自由呼吸(FB)的放疗计划进行剂量学参数比较。方法入选病人完成ABC呼吸训练后,进行CT模拟定位,TPS计划设计,摆位验证以及实施放疗,评估ABC应用于原发性肝癌放疗的可行性,ABC放疗的摆位误差和肝脏位置的重复性,并且与平静呼吸的放疗计划比较计划靶体积(PTV)、未受肝癌累及的正常肝脏的平均剂量(MDTNL)、接受≥23Gy照射的肝脏体积比(V23)和放射性肝病的发生概率(NTCP)等剂量学参数。结果有11例病人入选该研究,所有病人配合良好,没有因为不能耐受屏气而中断放疗者。PTV的平均体积由FB下的757cm3±475cm3减少到了ABC技术的444cm3±297cm3(P=0.002)。ABC技术下的平均MDTNL为15.9Gy±5.4Gy,而FB则为24.6Gy±6.5Gy(P<0.01)。ABC计划和FB计划平均的V23分别为31%和55%,而NTCP分别为11%和21%。ABC放疗的随机误差和系统误差在头脚、前后和左右方向分别为4.8mm和1.3mm、3.5mm和1.6mm以及2.4mm和1.7mm,肝脏位置一次放疗内和分次放疗间在头脚方向上的重复性平均分别为1.5mm(范围:0.5～3.0mm)和5.1mm(范围:1.9～9.2mm)。ABC放疗所需的时间平均为6分钟(范围:5～14分钟)。结论ABC技术用于肝癌放疗是可行的。没有显著增加治疗时间,摆位精确性和重复性好。该技术能减少正常肝的照射体积,降低平均剂量,减少了放射性肝病的发生概率。     

Anti-Soluble Liver Antigen (SLA) Antibodies in Chronic HCV Infection

Hepatitis C infection is associated with autoimmune disorders, such as the production of autoantibodies. Anti-LKM1 and anti-LC1, immunomarkers of type 2 autoimmune hepatitis, have been previously associated with a HCV infection. Anti-Soluble-Liver-Antigen autoantibodies (SLA) are specifically associated with type 1 and type 2 autoimmune hepatitis and more closely related to patients who relapse after steroid therapy. The recent molecular cloning of the soluble liver antigen provides the opportunity to develop more specific tests for the detection of antibodies against it. The aim of this work is to characterize anti-soluble-liver autoantibodies in sera from patients chronically infected by HCV. A recombinant cDNA from activated Jurkat cells coding for the full length tRNP^(Ser)Sec/SLA antigen was obtained. ELISA, Western Blot and immunoprecipitation tests were developed and used to search for linear and conformational epitopes recognized by anti-SLA antibodies in sera from patients chronically infected by HCV. Anti-soluble liver antigen antibodies were found in sera from 10.4% of HCV-infected patients. The prevalence was significantly increased to 27% when anti-LKM1 was also present. Most anti-SLA reactivity was directed against conformational epitopes on the antigen. The means titers by ELISA were lower than those obtained in type 2 AIH. The result of autoantibody isotyping showed a subclass restriction to IgG1 and also IgG4. This study shows the presence of anti-SLA antibodies in approximately 10% of HCV infected patients. The prevalence of SLA autoantibodies in HCV infected patients increases when LKM1 autoantibodies are also present. The relationship between the prevalence of this characteristic autoimmune hepatitis autoantibody and the implication of an autoimmune phenomenon in the liver injury of patients chronically infected by HCV needs further investigation.     

Ablation of p21-activated kinase-1 in mice promotes isoproterenol-induced cardiac hypertrophy in association with activation of Erk1/2 and inhibition of protein phosphatase 2A

Earlier investigations in our lab indicated an anti-adrenergic effect induced by activation of p21-activated kinase (Pak-1) and protein phosphatase 2A (PP2A). Our objective was to test the hypothesis that Pak-1/PP2A is a signaling cascade controlling stress-induced cardiac growth. We determined the effects of ablation of the Pak-1 gene on the response of the myocardium to chronic stress of isoproterenol (ISO) administration. Wild-type (WT) and Pak-1-knockout (Pak-1-KO) mice were randomized into six groups to receive either ISO, saline (CTRL), or ISO and FR180204, a selective inhibitor of Erk1/2. Echocardiography revealed that hearts of the Pak-1-KO/ISO group had increased LV fractional shortening, reduced LV chamber volume in diastole and systole, increased cardiac hypertrophy, and enhanced transmitral early filling deceleration time, compared to all other groups. The changes were associated with an increase in relative Erk1/2 activation in Pak-1-KO/ISO mice versus all other groups. ISO-induced cardiac hypertrophy and Erk1/2 activation in Pak-1-KO/ISO were attenuated when the selective Erk1/2 inhibitor FR180204 was administered. Immunoprecipitation showed an association between Pak-1, PP2A, and Erk1/2. Cardiac myocytes infected with an adenoviral vector expressing constitutively active Pak-1 showed a repression of Erk1/2 activation. p38 MAPK phosphorylation was decreased in Pak-1-KO/ISO and Pak-1-KO/CTRL mice compared to WT. Levels of phosphorylated PP2A were increased in ISO-treated Pak-1-KO mice, indicating reduced phosphatase activity. Maximum Ca²⁺-activated tension in detergent-extracted bundles of papillary fibers from ISO-treated Pak-1-KO mice was higher than in all other groups. Analysis of cTnI phosphorylation indicated that compared to WT, ISO-induced phosphorylation of cTnI was blunted in Pak-1-KO mice. Active Pak-1 is a natural inhibitor of Erk1/2 and a novel anti-hypertrophic signaling molecule upstream of PP2A.     

2010年渝东北HIV初筛阳性样品复检及确证情况分析

目的:了解2010年渝东北地区艾滋病病毒(HIV)抗体的初筛阳性样品的复检及确证情况,促进艾滋病筛查实验室网络建设及检测能力的提高。方法:对2010年渝东北地区艾滋病筛查实验室初筛阳性送检样品及本室初筛阳性的共计228份样品进行复检与确证,并对其检测结果进行分析比较。结果:经本室酶联免疫吸附试验(ELISA)复检,228份样品中,有177份HIV抗体待确证(177/228,77.63%),通过确证查重和信息核对,除去已经确证和身份信息不全的9份后,经WB试验确证检测168份,有121份为HIV-1抗体阳性(121/168,72.02%),29例HIV抗体阴性(29/168,17.26%),18例HIV抗体不确定(18/168,10.71%)。结论:艾滋病筛查实验室应进一步加强实验室规范化管理,消除引起初筛试验假阳性结果的因素。     

Responses to Norepinephrine of Normal and "Ischemic" Canine Purkinje Fibers are Consistent with Activation of Different α1-Receptor Subtypes

α₁-Receptor Subtype Stimulation of Purkinje Fibers. Introduction: Previously we found that WB4101 (WB) 10^-7 M competitively blocks three α₁-adrenergic receptor-effector responses: the increase in normal automaticity occurring in Purkinje fibers (PF) at high membrane potentials: the increase in abnormal automaticity occurring in PF at depolarized membrane potentials; and the prolongation of PF action potential duration. These observations are consistent with two different hypotheses: (1) WB blocks a single α₁-receptor subtype, which subserves different effector pathways; and (2) WB blocks different receptor subtypes, eacb of which subserves an independent patbway. The aim of this study was to test both hypotheses. Methods and Results: We used standard microelectrode techniques to study the concentration-dependent actions of three α₁-adrenoreceptor blockers (WB (α_1A?α_1D], 5-methylurapidil [5-MU] [α_1A, ?α_1D], and UK52,046 [nonselective]) on norepinephrine (NK) effects in normal PF and in PF depolarized with a simulated ischemic solution ([K⁺]_o= 10 mM; pO₂ < 20 mmHg; pH 6.8; maximum diastolic potential -60 ± 1 mV). In normally polarized PF, concentration-dependent actions of all blockers on both the positive cbronotropic response and the prolongation of action potential duration completely coincide. In contrast, the response to NE of abnormal automaticity in “ischemic” PF differs from normals: there is a bigh sensitivity to WB and 5-MU and no response to UK52,046. Conclusions: (1) A single receptor subtype appears responsible for botb the α₁-induced prolongation of repolarization and the positive chronotropic effect in normal PF. (2) Two different receptor subtypes may be responsible for the α₁-induced effects on automaticity in normal and ischemic fibers. It is likely that the latter one is α_1A, and that consideration of antiarrhythmic therapy with α₁-adrenergic blockers should focus on this subtype as a potential target.     

一例HIV抗体蛋白免疫印迹法检测条带不全病例的分析

目的通过对最近一例艾滋病病毒(HIV)抗体实验室检测"不确定"结果的分析讨论,尽可能减少实验室"不确定"结果的比例,提高实验室HIV确证实验的质量。方法该病例的血清标本采用两种酶联免疫吸附试验(ELISA)及两种快诊实验检测,又用蛋白免疫印迹法(WB)进行确证实验,并结合流行病学资料、核酸检测和基因测序结果,对该样本进行全面分析。结果 2012年11月至2013年3月期间,一例首次来自上海市肺科医院,两次随访均来自浦东新区自愿咨询检测门诊(VCT)的病例,ELISA和快诊检测为HIV抗体阳性,但WB确证结果首次为"不确定",第2、第3次随访结果也均为"不确定",后经核酸检测结果为阳性,基因测序结果为HIV-1型的CRF01_AE重组亚型,符合该病例的流行病学调查资料。结论对确证试验为"不确定"的病例,应综合初筛结果和实验室辅助检测手段及流行病学史,尽早明确个体HIV感染情况。     

Significance of platelet and monocyte activation for therapeutic immunoglobulin-induced thromboembolism

Objectives

Thromboembolic events (TEE) in patients receiving infusions of intravenous immunoglobulin (IVIG) products have recently been associated with contaminating factor XIa. We studied whether platelet and monocyte activation could also be involved.

Methods

Twenty IVIG samples from five manufacturers were tested for the induction of visible whole blood clot formation. A selection of TEE-associated and not associated lots was further analyzed for effects on thromboelastometry, platelet activation and adhesion, as well as monocyte tissue factor surface expression. Pure factor XIa was included for comparison. Western blotting was applied to analyze anti-CD154-reactive proteins in IVIG.

Results

In whole blood, IVIG enhanced macroscopic clotting additively with factor XIa. In monocytes, all IVIG products induced the FcγRII-dependent tissue factor expression to a similar extent, which was not affected by addition of factor XIa. Testing platelet aggregation, IVIG strengthened the ADP and TRAP-6-elicited response. Furthermore, IVIG increased platelet-monocyte adhesion and annexin V binding to platelet microvesicles, and promoted platelet adhesion to IVIG-coated surfaces. The strongest effects were observed with TEE-associated lots. CD154-related proteins were detected in all IVIG products. CD154-related high molecular weight complexes were particularly found in the TEE-associated IVIG. In platelet aggregation, recombinant soluble CD154 enhanced aggregate formation and stability.

Conclusion

Our data demonstrate that IVIG modulate platelet and monocyte activation and can thereby affect the hemostatic balance. These effects are either additive to or independent from factor XIa. CD154-related proteins are assumed to be involved in these interactions, the mechanism of which needs to be elucidated in further studies.     

Immune response to autologous transfusion in healthy volunteers: WB versus packed RBCs and FFP

BACKGROUND: Storage of blood as packed RBCs and FFP is standard practice in allogeneic transfusion. Separation into components has been proposed for autologous transfusion, as well, but beneficial effects have not yet been shown. STUDY DESIGN AND METHODS: Twenty-four healthy male volunteers were randomly assigned to receive 1 unit of either autologous RBCs and FFP (RCP group) or WB (WB group) after 49 or 35 days of storage, respectively. The immune response was analyzed by ELISA for IL-6, C3a, terminal complement complex SC5b-9, TNF-alpha, and neopterin. Differential WBC counts and the phagocytosis of neutrophils and monocytes were measured by flow cytometry. RESULTS: Cell counts of monocytes (0.85 x 10(3) ng/microL) [corrected] and neutrophils (6.9 x 10(3) ng/microL) [corrected] increased 30 minutes after WB transfusion and then returned to close to the baseline values seen in the RCP group (0.47 and 2.9 x 10(3) ng/microL [corrected], respectively) throughout the monitored period (p<0.05). C3a (169 vs. 116 ng/microL) [corrected] and IL-6 (29 vs. 6 pg/mL) reached higher plasma concentrations in the WB group (n = 11) than in the RCP group (n = 10). Phagocytosis of opsonized Escherichia coli was increased in neutrophils and monocytes and lasted up to 7 days after the transfusion of whole blood. CONCLUSION: Autologous WB induces a modest immunomodulation, but this effect is not observed upon transfusion of autologous blood components.     

Antioxidant power as biochemical endpoint in bread for screening and early managing quality and toxicant-related safety anomalies in food production

Flaxseeds are both a food ingredient and a natural source of antioxidants (e.g. lignans, PUFAs) and pro-oxidant contaminants (e.g. cadmium): the variable mixture of anti- and pro-oxidant substances may impact on the redox homeostasis of flaxseed-enriched foods. The antioxidant power is studied here as biochemical activity of flaxseeds in white wheat bread and as endpoint for possible screening of anomalous variations of bioactive mixtures (antioxidants vs. prooxidants) in food matrices.A bioprobe assay based on the superoxide dismutase (SOD) enzyme (6 channels of the multiprobe bioelectronic platform BEST) was performed on white wheat bread with and without flaxseeds. Nine BEST channels were simultaneously used for validation and monitoring of measuring conditions (temperature, pH, conductivity). Findings were compared with quantitative analysis of antioxidants and pro-oxidant contaminants. Organic and aqueous extracts of both bread types were examined in parallel.The SOD-probe detected the difference in antioxidant power given by 10% flaxseed, thus supporting the use of antioxidant power detected by bioenzymatic screening as sensitive biochemical endpoint. Mixtures of bioactive molecules in foods generate biochemical activities that can be monitored as time-effective indicators of invariability, which is pivotal in the daily control of anomalies in food production and therefore in the protection of consumers′ health.