Preoperative glucocorticoids decrease pulmonary hypertension in piglets after cardiopulmonary bypass and circulatory arrest

BACKGROUND: Glucocorticoids during cardiopulmonary bypass benefit pediatric patients undergoing repair of congenital heart defects and are routine therapy, but underlying mechanisms have not been fully examined. The hypothesis was that glucocorticoids could improve cardiopulmonary recovery after cardiopulmonary bypass and deep hypothermic circulatory arrest. METHODS: Crossbred piglets (5 to 7 kg) were cooled with cardiopulmonary bypass, followed by 120-min deep hypothermic circulatory arrest. Animals were then warmed to 38 degrees C, removed from bypass, and maintained for 120 min. Methylprednisolone (60 mg/kg) was administered in the cardiopulmonary bypass pump prime (intraoperative glucocorticoids) or 6 hours before bypass (30 mg/kg) in addition to the intraoperative dose (30 mg/kg; preoperative and intraoperative glucocorticoids). Controls (no glucocorticoids) received saline. RESULTS: Pulmonary vascular resistance in controls increased from a baseline of 152 +/- 40 to 364 +/- 29 dynes. s/cm(5) at 2 hours of recovery (p < 0.001). Intraoperative glucocorticoids did not alleviate the increase in pulmonary vascular resistance (301 +/- 55 dynes. s/cm(5) at 2 hours of recovery, p < 0.001). However, animals receiving pre and intraoperative glucocorticoids had no increase in pulmonary vascular resistance (155 +/- 54 dynes. s/cm(5)). Plasma endothelin-1 in controls increased from 1.3 +/- 0.2 at baseline to 9.9 +/- 2.0 pg/mL at 2 hours recovery (p < 0.01), whereas glucocorticoid-treated animals had lower endothelin-1 levels (4.5 +/- 2.1 pg/ml, preoperative and intraoperative glucocorticoids; 4.9 +/- 1.7 pg/mL, intraoperative glucocorticoids) at the end of recovery (p < 0.05). Intracellular adhesion molecule-1 in lung tissue was lower in animals receiving pre and intraoperative glucocorticoids (p < 0.05). Myeloperoxidase activity was elevated in control lungs at 2 hours of recovery compared with glucocorticoid-treated groups (p < 0.05). Inhibitor kappaBalpha, the inhibitor of nuclear factor-kappaB, was higher in lungs of animals receiving glucocorticoids compared with controls (p < 0.05). CONCLUSIONS: Glucocorticoids prevented pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest, which was associated with reduced plasma endothelin-1. Glucocorticoids also reduced pulmonary intercellular adhesion molecule-1 and myeloperoxidase activity. Inhibition of nuclear factor-kappaB, along with reduced neutrophil activation, contributed to glucocorticoid alleviation of pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest.     

转化生长因子-β1及p21对乳腺癌干细胞的作用

目的 观察转化生长因子-β1 (TGF-β1)诱导乳腺癌耐阿霉素细胞株MCF7/ADM中乳腺癌干细胞富集的作用,比较乳腺癌干细胞和MCF7/ADM中 p21 基因和蛋白水平的表达差异.方法 流式细胞仪检测阿霉素耐药乳腺癌细胞(ADM细胞)、乳腺细胞球培养法富集的乳腺癌细胞(SC细胞)及加入TGF-β1细胞因子诱导的乳腺癌细胞(SC-T细胞)中乙醛脱氢酶1(ALDH1)阳性细胞比例;比较上述3组细胞微球形成能力差异;逆转录-聚合酶链反应(RT-PCR)及Western blot检测3组细胞中p21基因及蛋白水平的表达差异.结果 ADM组、SC组及SC-T组中ALDH1阳性细胞比例分别为8.49％、14.94％及23.44％;细胞微球形成率分别为5.29％、11.67％、23.13％;3组细胞中p21 mRNA及蛋白水平的表达均逐渐升高.结论TGF-β1能诱导乳腺癌干细胞的富集并使其具有更强的自我更新能力.P21在乳腺癌干细胞中高表达.     

基因沉默缺氧诱导因子-1α对BxPC-3细胞株糖酵解基因表达的影响

目的 观察沉默缺氧诱导因子(HIF)-1α基因表达对于缺氧微环境下人胰腺癌BxPC-3细胞株中糖酵解相关基因表达的影响.方法 通过合成小于扰RNA((siRNA))转染沉默BxPC-3细胞株中HIF-1α基因表达.将细胞分为空白对照组(BxPC-3)、空白质粒转染对照组(GFP)和HIF-1α基因沉默组(sh-HIF-1α),分别在正常环境(21.0％O2)和缺氧环境(0.5％～1.0％ O2)中培养48 h后,检测各组细胞中糖酵解相关基因[如丙酮酸激酶1(PDK-1)、乳酸脱氢酶A(LDH-A)和柠檬酸合成酶(CS)]的表达以及细胞糖酵解产物乳酸含量的改变.结果 与正常环境比较,缺氧培养后sh-HIF-1α组细胞内HIF-1αmRNA增加了12.4％,蛋白增加了1.6倍,显著低于BxPC-3组和GFP组(P＜0.05),PDK-1和LDH-A的表达也明显低于两个对照组(P＜0.05).相应的sh-HIF-1α组的乳酸含量为(4.8 ±0.3)nmol/106个细胞,明显低于BxPC-3组(9.1±0.5)nmol/106个细胞和GFP组(9.2±0.5) nmol/106个细胞(P＜0.05).相反,缺氧时BxPC-3组和GFP组细胞中与线粒体氧化磷酸化相关的CS基因表达明显下降,低于其在sh-HIF-1α组细胞中的表达(P＜0.05).结论 缺氧可以诱导BxPC-3细胞株中HIF-1α基因高表达并促进糖酵解相关的PDK-1和LDH-A等基因表达.而通过沉默HIF-1α基因,可以抑制上述基因的表达,并促进CS基因表达,从而抑制肿瘤细胞的糖酵解代谢.     

血清肿瘤标记物异柠檬酸脱氢酶1对肺癌的辅助诊断价值

目的 探讨血清肿瘤标记物异柠檬酸脱氢酶1(IDH1)对肺癌辅助诊断的临床价值。方法 收集一般资料,应用酶联免疫法检测肺癌患者、非肺癌人群血清中IDH1的浓度水平,并分析其在肺癌诊断中的临床意义。结果 肺癌患者血清中IDH1的浓度水平明显高于非肺癌人群[(7.12±6.98)ng/ml比(2.09±1.83)ng/ml,t=11.540,P<0.001];血清IDH1在腺癌和鳞癌中的浓度水平显著高于小细胞肺癌[(7.91±7.26)ng/ml比(2.76±2.27)ng/ml, t=6.345,P<0.001];血清IDH1在肺癌、Ⅰ+Ⅱ期肺癌、Ⅲ+Ⅳ期肺癌中检测的敏感度分别为47.4%、49.1%和46.3%。结论 血清IDH1的检测对于非小细胞肺癌(鳞癌和腺癌)和小细胞肺癌的诊断、鉴别诊断以及对Ⅰ和Ⅱ期肺癌的辅助诊断具有较高的敏感度和特异性,血液IDH1在肺癌的辅助诊断中具有良好的临床应用价值。     

甲状腺结节微波消融治疗后6个月消融区细胞活性的酶组织化学检测

目的 探讨甲状腺结节微波消融治疗术后6个月消融区组织内细胞活性情况。方法 选择2017年12月至2018年9月甲状腺结节微波消融治疗术后6个月进行消融区粗针穿刺活组织检查病理评估的患者20例24个消融区。使用切割式活检针分别对消融区中央域及边缘域进行粗针穿刺活组织检查,取得标本条置入液氮制成冰冻切片。采用酶组织化学染色法检测细胞内琥珀酸脱氢酶（SDH）和还原型烟酰胺腺嘌呤二核苷酸磷酸黄递酶（NADPH-d）的活性,并与常规病理切片H-E染色观察到的细胞形态及组织结构对比。结果 微波消融术后6个月24个消融区的中央域及边缘域均成功取材。消融区中央域SDH及NADPH-d酶组织化学染色情况一致性好,阴性率均为95.83%（23/24）。消融区边缘域SDH及NADPH-d酶组织化学染色情况一致性好,阴性率均为91.67%（22/24）。23个中央域及22个边缘域的H-E染色切片均显示为红染无结构的大片坏死组织;1个中央域、2个边缘域H-E染色切片显示部分为坏死结构、部分为纤维组织增生,纤维组织增生处与酶组织化学染色阳性区域位置一致。结论 微波消融术后6个月甲状腺结节消融区组织符合凝固性坏死改变,仍处于失活状态,酶组织化学染色结合H-E染色能够对陈旧消融区做出较为客观的评价。     

Increased Expression of Aldehyde Dehydrogenase 2 Reduces Renal Cell Apoptosis During Ischemia/Reperfusion Injury After Hypothermic Machine Perfusion

Hypothermic machine perfusion (MP) can reduce graft's injury after kidney transplantation; however, the mechanism has not been elucidated. In the past decade, many studies showed that aldehyde dehydrogenase 2 (ALDH2) is a protease which can inhibit cell apoptosis. Therefore, this study aims to explore whether ALDH2 takes part in reducing organ damage after MP. Eighteen healthy male New Zealand rabbits (12 weeks old, weight 3.0 ± 0.3 kg) were randomly divided into three groups: normal group, MP group, and cold storage (CS) group (n = 6). The left kidney of rabbits underwent warm ischemia for 35 min through clamping the left renal pedicle and then reperfusion for 1 h. Left kidneys were preserved by MP or CS (4°C for 4 h) in vivo followed by the right nephrectomy and 24‐h reperfusion, and then the specimens and blood were collected. Finally, concentration of urine creatinine (Cr), blood urea nitrogen (BUN), and 4‐HNE were tested. Renal apoptosis was detected by TUNEL staining, and the expression of ALDH2, cleaved‐caspase 3, bcl‐2/ bax, MAPK in renal tissue was detected by immunohistochemistry or Western blot; 24 h after surgery, the concentration of Cr in MP group was 355 ± 71μmol/L, in CS group was 511 ± 44 μmol/L (P < 0.05), while the BUN was 15.02 ± 2.34 mmol/L in MP group, 22.64 ± 3.58 mmol/L in CS group (P < 0.05). The rate of apoptosis and expression of cleaved caspase‐3, p‐P38, p‐ERK, and p‐JNK in MP group was significantly lower than that in CS group (P < 0.05), while expression of ALDH2 and bcl‐2/bax in MP group was significantly higher than that in CS group (P < 0.05); expression of cleaved caspase‐3 in both MP and CS group significantly increased as compared with that in normal group (P < 0.05). In conclusion, increased expression of ALDH2 can reduce the renal cell apoptosis through inhibiting MAPK pathway during ischemia/reperfusion injury (IRI) after hypothermic MP.     

血清降钙素原、C-反应蛋白及脑脊液乳酸脱氢酶检测在小儿中枢神经系统感染的价值

目的：探讨与分析血清降钙素原、C-反应蛋白及脑脊液乳酸脱氢酶检测在小儿中枢神经系统感染的价值。方法随机选取2010年4月-2014年4月于该院接受治疗的60例中枢神经系统感染患儿作为研究对象,所有患儿均在入院后实施血清降钙素原、C-反应蛋白及脑脊液乳酸脱氢酶检测,评估其诊断价值。结果细菌感染组患儿血清内PCT、CRP及脑脊液LDH浓度水平明显高于病毒感染组,差异有统计学意义(P<0.05)。三者联合检测灵敏度与准确度明显高于单项检测与两项联合检测,差异有统计学意义(P<0.05)。结论三者联合检测可有效提升小儿中枢系统感染的检出率,同时在鉴别病毒性与细菌性感染方面有一定的价值,有利于早期的鉴别诊断及积极治疗。     

大豆异黄酮对糖尿病大鼠心肌损伤的保护作用

目的:研究大豆异黄酮对糖尿病大鼠心肌损伤的保护作用。方法:采用腹腔注射链脲佐菌素(streptozotocin,STZ)的方法制备2型糖尿病大鼠模型,取100只模型大鼠随机分为模型组,大豆异黄酮40 mg·kg~(-1)组、80 mg·kg~(-1)组、160mg·kg~(-1)组、320 mg·kg~(-1)组,每组20只;另设正常对照组。给药治疗8周后,测定各组大鼠体质量和心脏指数;检测血清中谷草转氨酶(aspartate transaminase,AST)、乳酸脱氢酶(lactate dehydrogenase,LDH)、肌酸激酶(creatine kinase,CK)、丙二醛(Malondialdehyde,MDA)含量以及总抗氧化能力(total antioxidant capacity,TAOC);测定心肌组织中超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)活性;通过苏木精-伊红(Hematoxylin-Euphorbia,HE)染色观察心肌组织病理学改变,通过TUNEL染色观察心肌细胞凋亡状况并计算凋亡指数(apoptosis index,AI)。结果:与模型组比较,大豆异黄酮80 mg·kg~(-1)组、160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠血清AST、LDH、CK、MDA水平显著降低(P0.05,P0.01),心肌组织中SOD、CAT活性显著升高(P0.05,P0.01);大豆异黄酮160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠体质量显著增高、心脏指数显著降低(P0.05);血清中TAOC显著升高(P0.05);大豆异黄酮各组心肌组织病理学改变和心肌细胞凋亡程度均出现不同程度的改善,并且大豆异黄酮160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠心肌细胞AI显著降低(P0.05,P0.01)。上述各指标变化均以320 mg·kg~(-1)组最为显著。结论:大豆异黄酮能够有效改善糖尿病大鼠体质量,降低心脏指数,改善心肌组织抗氧化酶系统活性、抑制自由基损伤,抑制心肌组织病变和细胞凋亡,提示大豆异黄酮对糖尿病大鼠心肌组织具有保护作用。     

Reduced 11beta-hydroxysteroid dehydrogenase activity in experimental nephrotic syndrome.

BACKGROUND: The disease state of the nephrotic syndrome is characterized by abnormal renal sodium retention that cannot be completely explained by a secondary hyperaldosteronism for the following reasons. Firstly, in rats an enhanced sodium retention is observed before proteinuria with intravascular volume depletion occurs. Secondly, in patients with the nephrotic syndrome, volume expansion with hypertension has been reported despite suppression of the renin-aldosterone system. Therefore, another mechanism for sodium retention must be postulated for this disease state. We hypothesize that this mechanism is a reduced 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) activity, a phenomenon known to cause enhanced access of cortisol or corticosterone to the mineralocorticoid receptor. METHODS: We assessed the 11beta-HSD activity by measuring the urinary ratio of tetrahydrocorticosterone (THB) plus 5alpha-tetrahydrocorticosterone (5alpha-THB) to 11-dehydro-tetrahydrocorticosterone (THA) by gas chromatography-mass spectrometry in rats with puromycin aminonucleoside (PAN)-induced proteinuria and with adriamycin nephrosis. Furthermore, the plasma ratios of corticosterone to 11-dehydrocorticosterone were measured. RESULTS: The urinary ratio of (THB+5alpha-THB)/THA increased in all animals following injection of PAN or adriamycin, indicating a reduced activity of 11beta-HSD. The reduced activity of 11beta-HSD was confirmed by an increased plasma ratio of corticosterone to 11-dehydrocorticosterone. The changes in the glucocorticoid metabolite ratios were already present before significant proteinuria appeared. CONCLUSION: PAN- or adriamycin-treated rats develop proteinuria with a reduced activity of 11beta-HSD, a mechanism contributing to the abnormal sodium retention in nephrotic syndrome.