单倍体异基因淋巴细胞输注在小鼠移植物抗宿主病和移植物抗肿瘤效应中的意义

目的建立小鼠免疫耐受模型,探讨单倍体异基因淋巴细胞输注在小鼠移植物抗宿主病（GVHD）和移植物抗肿瘤（GVT）效应中的意义。方法64只BALB／C雌性小鼠按随机数字表法分为4组,每组16只。对照组：实验第4天接种肿瘤细胞（小鼠大肠癌CT26细胞株配制成1×10^7／mL的瘤细胞悬液,接种到雌性小鼠右腋皮下）后不予任何特殊处理;化疗组：实验第4天接种肿瘤细胞,第7天开始化疗;供体淋巴细胞输注（DLI）组：实验开始时进行预处理,第4天接种肿瘤细胞,第13、15、17天输注单倍体异基因淋巴细胞（雄性BALB／C小鼠制备的脾淋巴细胞）;化疗＋DLI组：实验开始时进行预处理,第4天接种肿瘤细胞,第7天开始化疗,第13、15、17天输注单倍体异基因淋巴细胞。预处理方案为输注单倍体异基因淋巴细胞＋环磷酰胺＋输注单倍体异基因淋巴细胞。化疗方案为小鼠接种肿瘤细胞后第3天给予环磷酰胺腹腔化疗。每日观察各组小鼠临床GVHD的指标,并给予临床评分。观察荷瘤鼠肿瘤生长情况,计算接种成功后首日到小鼠死亡的时间和肿瘤质量,计算抑瘤率。应用流式细胞仪检测各组小鼠外周静脉血中T细胞数量,接种后15d各组处死3只小鼠取瘤体制作成观察切片,HE染色后光镜观察。多组比较采用方差分析,组间比较采用LSD—t检验。结果化疗＋DLI组的小鼠GVHD临床表现轻于其他组小鼠。对照组、化疗组、DLI组、化疗＋DLI组GVHD评分分别为（2．3±0．6）分、（1．5±1．1）分、（6．7±0．9）分、（3．4±0．5）分,4组比较,差异有统计学意义（F=148．68,P〈0．05）。4组小鼠全部接种CT26细胞成功。对照组、化疗组、DLI组、化疗＋DLI组小鼠肿瘤质量分别为（3．40±0．20）g、（0．80±0．10）g、（2．20±0．20）g、（0．50±0．30）g,4组比较,差异有统计学意义（F=149．17,P〈0．05）;4组小鼠抑瘤率分别为0、77％±9％、35％±3％、85％±44％;4组小鼠CD3’分别为52．3％±2．9％、44．8％±3．1％、62．9％±3．5％、65．9％±3．3％,4组比较,差异有统计学意义（F：28．04,P〈0．05）;4组小鼠CD3＋CD4＋分别为32．1％±2．6％、27．1％±1．1％、42．6％±1．8％、41．7％±2．4％,4组比较,差异有统计学意义（F=40．29,P〈0．05）;4组小鼠CD3＋CD8＋分别为22．7％±2．2％、20．7％±1．8％、26．7％±0．8％、26．1％±0．7％,4组比较,差异有统计学意义（F=10．74,P〈0．05）;4组小鼠CD3＋CD＋CD25＋分别为8．7％±0．6％、6．6％±0．6％、11．2％±0．4％、13．3％±0．7％,4组比较,差异有统计学意义（F=82．88,P〈0．05）。4组小鼠的肿瘤组织均有不同程度的坏死、出血,其中DLI组和化疗＋DLI组肿瘤组织大片坏死,瘤细胞变小,间质内有大量炎性细胞浸润,化疗＋DLI组还可见大量增生的淋巴滤泡。对照组、化疗组、DLI组、化疗＋DLI组小鼠生存时间分别为（16．8±2．5）d、（26．3±2．9）d、（23．4±2．5）d、（33．7±4．6）d,4组比较,差异有统计学意义（F=46．45,P〈0．05）。结论（1）预处理方案可以诱导小鼠的特异性免疫耐受。（2）单倍体异基因淋巴细胞输注与化疗具有协同作用,联合应用可以抑制小鼠皮下移植瘤瘤体的生长以及延长小鼠的生存时间。（3）化疗可降低供体淋巴细胞输注后诱发的GVHD效应并且提高了GVT效果。（4）CD3＋CIN＋CD25＋T淋巴细胞在降低GVHD反应中起着重要的作用。     

Hemodynamic effects of contrast media during coronary angiography: a comparison of three nonionic agents to Hypaque-76

Coronary angiography with standard ionic contrast media is associated with marked alterations in cardiac hemodynamics because of the depressant effects of the contrast media on cardiac contractility. Nonionic contrast media have been reported to produce less hemodynamic alteration than standard ionic contrast media. However, there is no information on how one nonionic media compares to another. Thus we compared the hemodynamic effects of three nonionic contrast media, Iopamidol (IOP), Iohexol (IOH), and Ioversol (IOV) to each other as well as to the standard ionic contrast media Hypaque-76 (H76). In 20 closed-chest anesthetized dogs, we recorded the maximal change in left ventricular systolic pressure (LVSP), mean aortic pressure, left ventricular diastolic pressure (LVDP), and left ventricular dp/dt during 10-cc left main coronary artery injections of H76, IOP, IOH, and IOV. The mean aortic pressure and LVSP decreased 36 +/- 17 mm Hg and 46 +/- 21 mm Hg with H76 but only 5 +/- 5 mm Hg and 6 +/- 5 mm Hg with IOP, 5 +/- 4 mm Hg and 6 +/- 6 mm Hg with IOH, and 5 +/- 4 mm Hg and 7 +/- 6 mm Hg with IOV (P less than 0.001). The LVDP increased 6 +/- 5.0 mm Hg with H76 but only 0.2 +/- 0.5 mm Hg with IOP, 0.2 +/- 0.3 mm Hg with IOH, and 0.5 +/- 1.0 mm Hg with IOV (P less than 0.001). The LV dp/dt decreased 545 +/- 261 mm Hg/sec with H76 but increased 886 +/- 477 mm Hg/sec with IOP, 910 +/- 96 mm Hg/sec with IOH, and 473 +/- 335 mm Hg/sec with IOV (P less than 0.001). Whereas each nonionic agent produced significantly less hemodynamic abnormalities than H76, there was no significant difference between any of the nonionic agents on any hemodynamic parameter. Thus, as compared to H76, these nonionic contrast media produced only trivial alterations in hemodynamics and LV dp/dt. These agents may be preferable in patients with LV dysfunction.     

Oncogenic mutation in the Kit receptor tyrosine kinase alters substrate specificity and induces degradation of the protein tyrosine phosphatase SHP-1

Activating mutations in the Kit receptor tyrosine kinase have been identified in both rodent and human mast cell leukemia. One activating Kit mutation substitutes a valine for aspartic acid at codon 816 (D816V) and is frequently observed in human mastocytosis. Mutation at the equivalent position in the murine c-kit gene, involving a substitution of tyrosine for aspartic acid (D814Y), has been described in the mouse mastocytoma cell line P815. We have investigated the mechanism of oncogenic activation by this mutation. Expression of this mutant Kit receptor tyrosine kinase in a mast cell line led to the selective tyrosine phosphorylation of a 130-kDa protein and the degradation, through the ubiquitin-dependent proteolytic pathway, of a 65-kDa phosphoprotein. The 65-kDa protein was identified as the src homology domain 2 (SH2)-containing protein tyrosine phosphatase SHP-1, a negative regulator of signaling by Kit and other hematopoietic receptors, and the protein product of the murine motheaten locus. This mutation also altered the sites of receptor autophosphorylation and peptide substrate selectivity. Thus, this mutation activates the oncogenic potential of Kit by a novel mechanism involving an alteration in Kit substrate recognition and the degradation of SHP-1, an attenuator of the Kit signaling pathway.     

Attenuation of lysophosphatidylcholine-induced suppression of ANP release from hypertrophied atria

Lysophosphatidylcholine (LPC) is an endogenous phospholipid released from the cell membrane during ischemia, and it has potent cardiac effects, including inhibition of atrial natriuretic peptide (ANP) release. The aim of this study was to investigate the effects of LPC on hemodynamics and ANP release in hypertrophied atria and to define its mechanism. Isolated, perfused, beating, hypertrophied atria from monocrotaline-treated rats were used. LPC (30 micromol/L), a mixture of stearoyl-LPC, palmitoyl-LPC, and oleoyl-LPC, caused suppression of ANP release, which was markedly attenuated in hypertrophied atria compared with nonhypertrophied atria. Suppression of ANP release by stearoyl-LPC, palmitoyl-LPC, or oleoyl-LPC was also attenuated in hypertrophied atria. The potency appeared to be dependent on the species of fatty acid residue of LPC. Changes in ANP release by LPC, palmitoyl-LPC, and oleoyl-LPC were positively correlated with the degree of cardiac hypertrophy, but that by stearoyl-LPC was not. Changes in ANP release by LPC also were negatively correlated with changes in pulse pressure. Stearoyl-LPC caused an increase in intracellular Ca2+ in single, atrial myocytes in a concentration-dependent manner, which was markedly attenuated in hypertrophied atrial myocytes. These results suggest that attenuation of LPC-induced suppression of ANP release from hypertrophied atria might partly be related to changes in pulse pressure in terms of cardiac hypertrophy and/or disturbance of intracellular Ca2+ regulation.     

The mechanism and significance of ventricularization of intracoronary pressure during coronary angiography

Ventricularization of pressure during coronary angiography has been said to identify the presence of left main coronary artery disease, but the hemodynamic features and the mechanism of this process have not been studied. Twenty consecutive patients with ventricularization were identified prospectively in our laboratory. Four patients had a discrete ostial left main stenosis and 16 patients had stenosis of the entire length of the left main coronary artery. The degree of pressure drop upon cannulation of the diseased left main coronary artery was highly variable; the systolic pressure decreased by 9 to 94 mm Hg, and the diastolic pressure decreased by 6 to 60 mm Hg. The morphology of the ventricularized pressure was distinct. It had a presystolic deflection resembling an a wave. The upstroke of this waveform was slower and the downstroke was steeper than that of the aortic pressure. An identical waveform was observed in dogs after partial occlusion of the left main coronary artery with a balloon-tipped catheter. The waveform of the so-called ventricularized pressure is derived from the aortic pressure, which is altered by its transmission across the left main coronary stenosis. The appearance of ventricularization is an important clue to the presence of left main coronary artery disease.     

Endoscopic management for pancreatic injuries due to blunt abdominal trauma decreases failure of nonoperative management and incidence of pancreatic-related complications

Introduction

The actual benefit of endoscopic techniques in the non-operative management (NOM) of pancreatic injury is still unclear, with its role and effectiveness in the NOM of pancreatic injury remains defined and doubted. The purpose of this study was to evaluate the feasibility and long-term results of endoscopic techniques in the NOM of blunt pancreatic injury, and to determine whether NOM can be performed safely for selective patients with pancreatic injury.

Patients and methods

The records and follow-up data of all patients with blunt pancreatic injuries over 16-year period from October 1, 1996, to September 30, 2012 at our department were retrospectively reviewed. Failure of NOM (FNOM) occurred if laparotomy was required after attempted NOM.

Results

132 patients (32% of all patients with blunt pancreatic injury) underwent NOM, including 58 who underwent endoscopic management (EM) and 74 who were observed without EM (NO-EM). FNOM of overall NOM was 20%, including 30% of NO-EM and 9% of EM. There was no significant difference in FNOM for NO-EM versus EM for grade I, however, a significant decrease in FNOM was noted with the addition of EM for grade II and III. EM was a statistically significant independent risk factor. Regular follow-up of 1 year showed that, for patients from grade I to III, 53 patients (42%) from operative management (OM) and 34 patients (46%) of the NO-EM developed various pancreatic-related complications, while only 15 patients (26%) of the EM developed such complications, and the difference was significant.

Conclusion

Application of strictly defined selection criteria for NOM and EM in patients with blunt pancreatic injury resulted in one of the lowest FNOM rates (9%) and pancreatic-related complications incidence (25%). Selective application of EM for hemodynamically stable patients with blunt pancreatic injury will extend the indications for, and improve success of NOM.     

Exposure to ambient black carbon derived from a unique inventory and high-resolution model

Black carbon (BC) is increasingly recognized as a significant air pollutant with harmful effects on human health, either in its own right or as a carrier of other chemicals. The adverse impact is of particular concern in those developing regions with high emissions and a growing population density. The results of recent studies indicate that BC emissions could be underestimated by a factor of 2–3 and this is particularly true for the hot-spot Asian region. Here we present a unique inventory at 10-km resolution based on a recently published global fuel consumption data product and updated emission factor measurements. The unique inventory is coupled to an Asia-nested (∼50 km) atmospheric model and used to calculate the global population exposure to BC with fully quantified uncertainty. Evaluating the modeled surface BC concentrations against observations reveals great improvement. The bias is reduced from −88% to −35% in Asia when the unique inventory and higher-resolution model replace a previous inventory combined with a coarse-resolution model. The bias can be further reduced to −12% by downscaling to 10 km using emission as a proxy. Our estimated global population-weighted BC exposure concentration constrained by observations is 2.14 μg⋅m⁻³; 130% higher than that obtained using less detailed inventories and low-resolution models.Black carbon (BC), or soot, emitted from incomplete combustion of carbonaceous fuels is an air pollutant which also plays an important role in climate change (1). BC is an indicator of air particulate pollution and BC in ambient air has an impact on human health (2). In a recent study in China, it was found that the effects of BC on morbidity appear to be more robust than the effects of fine particles in general (3, 4).However, global atmospheric aerosol models often underestimate the concentration of BC at the surface, particularly over Asia, by a factor that typically ranges from 2 to 10 (5–7). In one study, the observed BC surface concentration for China could only be reproduced by doubling the emissions prescribed to a transport model (8). It is often argued that the underestimation is due to a low bias in BC emission inventories, suggesting a need to revisit these previous inventories (9).In a bottom-up approach, BC emission is estimated based on the amount of fuel consumed and an emission factor (EF_BC, defined as the amount of BC emitted per unit mass of fuel consumed) for each of various combustion sources. For previous inventories, the lack of EF_BC measurements in developing countries led to high uncertainty in estimating the total emissions (10). In addition, the use of fuel data at the national level is likely to distort the geographical distribution of emissions within large countries such as China and India (11). Recently, a 0.1° × 0.1° fuel database with 64 types of combustion has been developed based on local or national fuel consumption statistics. This database improves the resolution of the spatial distribution of emissions for large countries (12). To fill the data gap in developing countries, a set of EF_BC values has been compiled for various residential solid fuel combustion devices and vehicles (13–20). In addition to the problems with the emission inventories, the coarse resolution of existing global aerosol models also hinders our ability to capture detailed spatial variation, leading to poor agreement between model prediction and observations (7).In this study we develop and evaluate a unique global BC emission inventory using a zoomed aerosol model, and estimate the global population’s exposure to BC with a focus on Asia. The influence of model resolution and the use of an updated emission inventory on the calculated BC concentration are evaluated against field observations.