Effects of serum from rats with combined radiation-burn injury on the growth of hematopoietic progenitor cells

BACKGROUND: This study aims to observe the effects of blood serum from rats with radiation injury, burn injury, and combined radiation-burn injury on the growth of hematopoietic progenitor cells and to explore the possible mechanisms. METHODS: Serum from rats with radiation injury, burn injury, and combined radiation-burn injury were collected at 3 hours, 12 hours, 24 hours, 48 hours, 72 hours, and 96 hours after injury and then was added to the culture medium to see its effect on the growth of hematopoietic progenitor cells (HPCs) at a final protein concentration of 10 microg/mL. Radioimmunoassay and enzyme-linked immunosorbent assay were employed to measure the level of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 in each group, and the effect of TNF-alpha and IL-6 on the growth of HPC was also observed. RESULTS: The number of HPCs colonies formed after addition of the serum from rats with burn or combined radiation-burn injuries was significantly higher than that from normal rats at 3 hours, 12 hours, 24 hours, 48 hours, 72 hours, and 96 hours after injury and reached its peak value at 24 hours after injury. However, fewer HPCs colonies were found after the addition of the serum from irradiated rats. At the same time, the levels of TNF-alpha and IL-6 in the serum of burn group and combined radiation-burn injury group were significantly higher than that of normal group, and much higher than that of the irradiation injury group (p < 0.01). Also, TNF-alpha and IL-6 demonstrated promoting effect on the growth of HPC. CONCLUSION: Serum from rats with burn injury and combined radiation-burn injury stimulates the growth of HPCs, while serum from irradiated rats shows inhibitory effects on the growth of HPCs. These effects may lie in the different level of TNF-alpha and IL-6 in the serum of each group.     

右美托咪定对老年患者全身麻醉术后认知功能障碍及炎症反应的影响

目的 观察右美托咪定(dexmedetomidine,Dex)对全身麻醉术后炎症反应及术后认知功能障碍(postoperative cognitive dysfunction,POCD)的影响. 方法 选择行择期腹部手术全身麻醉患者60例,年龄60～75岁,采用随机数字表法分为Dex组(D组)和对照组(C组),每组30例,两组患者均采用咪达唑仑0.03～0.05 mg/kg、芬太尼2～3 μg/kg、丙泊酚0.5～1.5 mg/kg、顺式阿曲库铵0.15 mg/kg静脉注射进行麻醉诱导.D组在诱导前10 min内静脉泵入1μg/kg Dex,随后以0.2～0.7 μg·kg-1·h-1维持泵注,根据患者HR、BP等变化及时调整输注速率;C组则与D组相同时间和途径注入相同容积的生理盐水.分别于麻醉后手术前(T1)、手术结束后即刻(T2)、手术结束后24 h(T3)抽取静脉血测定血浆IL-6含量及外周血中性粒细胞NF-κB表达水平.术前1d或2d及术后第1、3、7天用简易智能量表(mini-mental state examination,MMSE)测定认知功能,使用简易精神测定表(abbreviated mental test,AMT)评定术后谵妄情况. 结果 13例患者出现POCD(21.67％),其中D组3例,C组10例,两组间差异有统计学意义(P＜0.05).两组T2、T3时点外周血中性粒细胞NF-κB表达均较T1时增加(P＜0.05),但D组表达水平低于C组(P＜0.05).两组T2时点血浆IL-6水平均较T1时点明显升高(P＜0.01),且C组显著高于D组(P＜0.01);两组T3时点血浆IL-6水平较T2时点明显下降,但仍高于T1时点(P＜0.05),T3时点两组间差异无统计学意义(P＞0.05).D组外周血中性粒细胞NF-κB表达水平与血浆IL-6有良好的相关性(r=0.65,P＜0.01). 结论 POCD的发生可能与氧化应激反应有关,抑制NF-κB的激活可减少术后炎症反应及POCD的发生.     

ICU内严重创伤患者死亡和自动出院趋势分析

目的 分析ICU内严重创伤患者死亡和自动出院的变化趋势,进一步提高严重创伤的救治效果. 方法 回顾性分析2003-2011年急诊ICU内死亡及自动出院严重创伤患者的临床资料.根据自动出院的状况分为濒死出院(病死人群)、病情恶化出院及好转出院,分析每年转归发生率的变化趋势,同时比较2003-2005年、2006-2008年和2009-2011年三个阶段的上述情况及总病死组、恶化出院组及总病死+恶化出院组的特征变化. 结果 (1)9年共有3 343例严重创伤患者收住急诊ICU,其中死亡231例(6.91％),包括院内死亡135例(4.04％)和濒死出院96例(2.87％);自动出院221例(6.61％),包括病情恶化出院175例(5.23％),好转出院46例(1.38％).最终452例纳入分析.(2)9年间院内病死率、濒死出院率及总病死率均呈下降趋势,恶化出院率呈上升趋势(x2=15.305,P＞0.05),但总病死+恶化出院率变化差异无统计学意义.(3)2003-2005年、2006-2008年和2009-2011年三个阶段分别收治687例、1 143例和1 513例,其中总病死组、恶化出院组、总病死+恶化出院组的年龄、急性生理与慢性健康评分Ⅱ(APACHEⅡ)升高,GCS下降.总病死率从11.06％降至4.63％(x2=31.174,P＜0.01),恶化出院率从2.77％升至6.35％(x2=12.203,P＜0.01),总病死+恶化出院率由13.83％下降至10.97％(x2=4.09,P＞0.05). 结论 2003-2011年医院急诊ICU的严重创伤救治水平呈提高趋势,恶化出院的比例增加且伴有年龄增大现象.自动出院对创伤救治效果的评价有较大影响,需引起重视.     

地塞米松对内毒素性急性肺损伤大鼠肺组织MKP-1表达的影响

目的 评价地塞米松对内毒素性急性肺损伤大鼠肺组织丝裂原活化蛋白激酶磷酸酶-1(MKP-1)表达的影响.方法 成年雄性SD大鼠54只,体重180～ 230 g,采用随机数字表法,将其随机分为3组:对照组(C组,n=6)、急性肺损伤组(ALI组,n=24)和地塞米松组(D组,n=24).ALI组和D组尾静脉注射LPS 5 mg/kg制备大鼠急性肺损伤模型,C组给予等容量生理盐水,D组于注射LPS前30 min时腹腔注射地塞米松6 mg/kg.C组于注射生理盐水后1 h(T1)时,ALl组和D组分别于注射LPS后1、3和6 h(T1-3)时,随机处死8只大鼠,取肺组织,检测MKP-1和磷酸化p38丝裂原活化蛋白激酶MAKP(p-p38MAPK)的表达.T3时回收支气管肺泡灌洗液(BALF),测定蛋白和TNF-α的浓度;观察肺组织病理学结果.另取32只SD大鼠,体重180～ 230 g,采用随机数字表法,将其随机分为2组(n=16):急性肺损伤组(ALI1组)和地塞米松组(D1组),处理方法同上.观察48 h内大鼠生存情况.结果 与C组比较,ALI组BALF中蛋白和TNF-α的浓度升高,T1-3时p-p38MAKP表达上调,T2.3时MKP-1表达下调,D组BALF中TNF-α浓度升高,T1-3时p-p38MAKP和MKP-1表达上调(P＜0.05);与ALI组比较,D组BALF中蛋白和TNF-α的浓度下降,T1-3时p-p38MAKP表达下调,MKP-1表达上调(P＜0.05),病理学损伤减轻.D1组大鼠生存率高于ALI1组(P＜0.05).结论 地塞米松减轻大鼠内毒素性急性肺损伤的机制与上调肺组织MKP-1的表达,抑制p38MAPK的磷酸化,降低炎性反应有关.     

日本血吸虫重组抗原的免疫原性鉴定

为发展新的日本血吸虫病疫苗候选抗原分子，对已构建的阳性表达克隆PGsj24进行大量诱导表达，制备为20kD的重组抗原。以之免疫家兔，产生了较强的抗体反应。该单特导抗血清可识别成上天然蛋白中与重组蛋白相对应的抗原成分。两者分子量及Westernblot识别反应带型均基本一致，说明约20kD重组蛋白确为日本血吸虫基因编码产物，具有较强的免疫原性，可刺激机体产生较强的免疫应答。     

结核分枝杆菌Rv1009基因蛋白的克隆和表达

目的克隆表达结核分枝杆菌促Rv1009基因,序列测定正确后进行融合、表达。方法采用热启动聚合酶链反应(Polymerase Chain Reaction,PCR)从结核分枝杆菌H37Rv基因组中扩增出Rv1009编码基因,用限制性内切酶消化后插入pGEX 4T-2载体中,将重组质粒转化大肠杆菌BL21 (DE3),目的基因经IPTG诱导,表达Rv1009基因蛋白。结果经PCR扩增在1300bp处发现一条目的片段,获得了结核分枝杆菌H37Rv株Rv1009基因蛋白,经诱导后高效表达分子量为64KD的外源蛋白,与预期分子量大小一致,凝胶自动扫描分析,在A600值为0．6,IPTG终浓度为0．3 mmol／L,诱导表达3 h时融合蛋白表达量即达峰值,占菌体总蛋白的22．8％。结论构建了结核分枝杆菌Rv1009基因重组表达载体,获得了RPF样融合蛋白的高效表达,为今后深入研究奠定了基础。     

SKLB1002, a novel inhibitor of VEGF receptor 2 signaling, induces vascular normalization to improve systemically administered chemotherapy efficacy

Vascular endothelial growth factor receptor (VEGFR) or vascular endothelial growth factor (VEGF) inhibitors have shown only modest clinical activity for most tumor types when used as single agents. However, present evidence indicates that these antiangiogenic drugs can cause transient "normalization" of the tumor vasculature, thereby improving the delivery of systemic chemotherapy. We examined temporal changes in tumor vascular function in response to the novel VEGFR2 inhibitor, SKLB1002. Established tumor-bearing animals were evaluated at serial time points for treatment-associated changes in tumor vascular architecture and function. As a result, blocking VEGF signaling by SKLB1002 produced a morphologically and functionally "normalized" vascular network. Consistent with our observations, a 2.2 fold increase in intratumoral doxorubicin levels was determined with SKLB1002 pretreatment compared with administration of doxorubicin alone. Finally, combined SKLB1002 and doxorubicin exhibited significant antitumor (49% of control size) and antimetastatic effects (12% of control metastatic nodules) in vivo. Our results showed SKLB1002 induced vascular normalization and enhanced anticancer drug delivery, which were associated with the observed synergistic effect in vivo.     

miR-7/TGF-β2 axis sustains acidic tumor microenvironment-induced lung cancer metastasis

Acidosis, regardless of hypoxia involvement, is recognized as a chronic and harsh tumor microenvironment (TME) that educates malignant cells to thrive and metastasize. Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression, the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy. Here, chemical-induced and transgenic mouse models for colon, liver and lung cancer were established, respectively. miR-7 and TGF-β2 expressions were examined in clinical tissues (n = 184). RNA-seq, miRNA-seq, proteomics, biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis. Our data show that lung cancer is sensitive to the increased acidification of TME, and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5p. TGF-β2 is a direct target of miR-7-5p. The reduced expression of miR-7-5p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer. Indeed, overexpression of miR-7-5p reduces the acidic pH-enhanced lung cancer metastasis. Furthermore, the human lung tumor samples also show a reduced miR-7-5p expression but an elevated level of activated TGF-β2; the expressions of both miR-7-5p and TGF-β2 are correlated with patients’ survival. We are the first to identify the role of the miR-7/TGF-β2 axis in acidic pH-enhanced lung cancer metastasis. Our study not only delineates how acidification directly affects tumorigenesis, but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer (NSCLC) treatment. Our study opens an avenue to explore the pH-sensitive subcellular components as novel therapeutic targets for cancer treatment.KEY WORDS: Acidic tumor microenvironment, miR-7-5p, TGF-β2, Metastasis, Lung cancer, pH, Invasion