过氧化氢对小鼠口腔癌发病影响的实验研究

目的检测氧化应激相关基因Nrf2、GST-π、HO1在4NQO小鼠舌癌标本中的表达水平,分析氧化损伤对4NQO诱导的小鼠口腔癌的促进作用。方法 190只8周龄雄性C57BL/6J小鼠随机分为阴性对照组、阳性对照组、6%、15%和30%过氧化氢处理组。阴性对照组不做任何处理,其余4组以0.005%4NQO诱癌16周后,分别用水(阳性对照组)和6%、15%、30%的过氧化氢涂抹小鼠舌部,每周3次,共8周。第24周末处死全部动物,取舌组织进行组织病理学分析及免疫组化染色。结果在粘膜从正常到异常增生、再到癌变的过程中,Nrf2、GST-π和HO1的表达持续升高,并且30%过氧化氢组中重度异常增生和癌变的组织中上述三者的积分光密度值显著高于阳性对照组(P0.01);6%和15%组中,GST-π的积分光密度值均显著高于阳性对照组(P0.05),Nrf2和HO1的积分光密度值与阳性对照组无统计学差异。结论过氧化氢造成的氧化损伤进一步促进了4NQO小鼠口腔癌的发展。     

The Number of Bleaching Sessions Influences Pulp Tissue Damage in Rat Teeth

Introduction

Hydrogen peroxide tooth bleaching is claimed to cause alterations in dental tissue structures. This study investigated the influence of the number of bleaching sessions on pulp tissue in rats.

Methods

Male Wistar rats were studied in 5 groups (groups 1S–5S) of 10 each, which differed by the number (1–5) of bleaching sessions. In each session, the animals were anesthetized, and 35% hydrogen peroxide gel was applied to 3 upper right molars. Two days after the experimental period, the animals were killed, and their jaws were processed for light microscope evaluation. Pulp tissue reactions were scored as follows: 1, no or few inflammatory cells and no reaction; 2, <25 cells and a mild reaction; 3, between 25 and 125 cells and a moderate reaction; and 4, 125 or more cells and a severe reaction. Results from each experimental group were compared between groups and within groups to the corresponding unbleached upper left molars and analyzed for significant differences using the Kruskal-Wallis test (P < .05).

Results

All tissue sections showed significant bleaching-induced changes in the dental pulp. After 1 bleaching session, necrotic tissue in the pulp horns and underlying inflammatory changes were observed. The extent and intensity of these changes increased with the number of bleaching sessions. After 5 sessions, the changes included necrotic areas in the pulp tissue involving the second third of the radicular pulp and intense inflammation in the apical third.

Conclusions

The number of bleaching sessions directly influenced the extent of pulp damage.     

Insufflation of Hydrogen Gas Restrains the Inflammatory Response of Cardiopulmonary Bypass in a Rat Model

Systemic inflammatory responses in patients receiving cardiac surgery with the use of the cardiopulmonary bypass (CPB) significantly contribute to CPB‐associated morbidity and mortality. We hypothesized that insufflated hydrogen gas (H₂) would provide systemic anti‐inflammatory and anti‐apoptotic effects during CPB, therefore reducing proinflammatory cytokine levels. In this study, we examined the protective effect of H₂ on a rat CPB model. Rats were divided into three groups: the sham operation (SHAM) group, received sternotomy only; the CPB group, which was initiated and maintained for 60 min; and the CPB + H₂ group in which H₂ was given via an oxygenator during CPB for 60 min. We collected blood samples before, 20 min, and 60 min after the initiation of CPB. We measured the serum cytokine levels of (tumor necrosis factor‐α, interleukin‐6, and interleukin‐10) and biochemical markers (lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase). We also measured the wet‐to‐dry weight (W/D) ratio of the left lung 60 min after the initiation of CPB. In the CPB group, the cytokine and biochemical marker levels significantly increased 20 min after the CPB initiation and further increased 60 min after the CPB initiation as compared with the SHAM group. In the CPB + H₂ group, however, such increases were significantly suppressed at 60 min after the CPB initiation. Although the W/D ratio in the CPB group significantly increased as compared with that in the SHAM group, such an increase was also suppressed significantly in the CPB + H₂ group. We suggest that H₂ insufflation is a possible new potential therapy for counteracting CPB‐induced systemic inflammation.     

硫化氢与血管内皮细胞的功能

血管内皮细胞参与血管内多种生理活动,内皮功能障碍将导致各种心血管疾病的发生.近几年来,研究发现新型气体信号分子硫化氢具有抗动脉粥样硬化等心血管疾病的效应:硫化氢促进内皮细胞增殖迁移诱导血管新生;抑制黏附分子分泌;通过打开平滑肌上ATP依赖性K+通道调节血管紧张度;抵抗氧化应激对内皮细胞的损伤等.随着其保护机制的不断发现与证实,硫化氢将有望逐渐应用于临床治疗,其.对内皮的保护作用仍需要做进一步的研究.     

非酒精性脂肪性肝病兔血浆丙二醛、超氧化物歧化酶与硫化氢、一氧化氮的关系

目的观察非酒精性脂肪性肝病(NAFLD)兔血浆超氧化物歧化酶(SOD)、丙二醛(MDA)、硫化氢(H2S)、一氧化氮(NO)关系。方法 40只日本大耳白兔随机分为重、轻度NAFLD组及对照组。重度组给予高脂饲料160 g/d,轻度组给予高脂饲料80 g/d+普通饲料80 g/d,对照组给予普通饲料160 g/d。饲养周期13 w,建立不同程度NAFLD模型。实验结束采集血浆标本,按设备、试剂操作常规检测SOD、MDA、H2S、NO。结果重、轻度组MDA较对照组明显增高(P<0.01,P<0.05),且重度组明显高于轻度组(P<0.05)。重、轻度组SOD活力较对照组明显减低,重度组明显低于轻度组(均P<0.01)。重度组、轻度组H2S水平较对照组明显降低(P<0.01),重、轻度组无显著差异(P>0.05)。重、轻度组NO较对照组明显升高(P<0.01)。重度组高于轻度组(P<0.01)。结论 NAFLD兔血浆MDA/SOD、H2S/NO平衡紊乱可能是NAFLD的发病机制。     

Combined effects of hydrogen sulfide and lipopolysaccharide on osteoclast differentiation in rats

Background: Lipopolysaccharide (LPS) stimulates osteoclast differentiation through toll‐like receptors (TLRs) 2 and 4, and hydrogen sulfide (H₂S) induces osteoclast differentiation. If H₂S activates TLRs, H₂S may enhance the effects of LPS on osteoclast differentiation. The purpose of the present study is to examine the combined effects of sodium hydrogen sulfide (NaHS, an H₂S donor drug) and LPS on osteoclast differentiation and TLR expression in rat periodontal tissue. Methods: Twenty‐eight male Wistar rats (8 weeks old) were divided into four groups (n = 7 per group): a control (no treatment) group and three experimental groups (NaHS group, LPS group, and a combination [NaHS + LPS] group). At 1 day after topical application of NaHS and/or Porphyromonas gingivalis LPS into the gingival sulcus of first molars, the number of tartrate‐resistant acid phosphate (TRAP)‐positive osteoclasts in the periodontal tissue was counted. Expression of TLR2 and TLR4 mRNAs and proteins in the gingival was also assessed. Results: The number of TRAP‐positive osteoclasts was significantly higher in the combination group than in any other group (P <0.01). The combination group had 11.0‐fold higher TLR4 mRNA levels than the control group. TLR4 protein levels were also higher in the combination group than in the NaHS or LPS group. However, the TLR2 mRNA and protein levels were not significantly different in the combination group and the LPS group. Conclusion: In rat periodontal tissue, NaHS and LPS had an additive effect on osteoclast differentiation through activation of the TLR4 pathway but not the TLR2 pathway.     

手足口病患儿血清硫化氢及白细胞介素-6水平改变的研究

目的：研究手足口病(hand,foot and mouth disease,HFMD)患儿血清硫化氢(hydrogen sulfide,H2 S)与白细胞介素(interleukin,IL)-6水平改变的意义。方法选择在我院住院治疗的92例HFMD 患儿为研究对象,根据病情,选择其中48例为重症 HFMD 组,44例为普通 HFMD 组,选择同期健康儿童46例为健康对照组。分别检测其血清 H2 S 及 IL-6水平。结果急性期：重症 HFMD 组与普通 HFMD 组血清 H2 S [(21.72±7.52)μmol /L、(31.86±8.41)μmol /L]水平均明显降低,IL-6[(131.33±17.82)ng /L、(95.48±15.07)ng /L]水平明显升高,与健康对照组[H2 S (55.76±7.80)μmol /L,IL-6(61.31±13.43)ng /L]比较差异有统计学意义(P ﹤0.01);重症 HFMD 组与普通HFMD 组比较差异有统计学意义(P ﹤0.01)。恢复期：重症 HFMD 组血清 H2 S[(34.54±13.21)μmol /L]水平仍低于健康对照组,IL-6[(92.73±15.25)ng /L]水平仍高于健康对照组,差异有统计学意义(P ﹤0.01)。相关性分析显示：重症 HFMD 组与普通 HFMD 组血清 H2 S 与 IL-6水平之间均呈显著负相关(r ＝-0.31,P ﹤0.01;r ＝-0.45,P ﹤0.01)。结论 HFMD 患儿血清 H2 S 和 IL-6水平发生了改变,并且可作为重症 HFMD 患儿早期诊断的指标之一。     

氢呼气试验在慢性肾脏病患者胃肠动力评估中的应用

目的 探讨氢呼气试验(hydrogen breath test,HBT)在慢性肾脏病患者胃肠动力评估中的应用.方法 92例慢性肾脏病(CKD)3b期～4期患者组成CKD组,其中3b期50例,4期42例.45例健康体检者组成对照组.分别应用胃肠电图与HBT对两组人群胃肠动力进行评估,其中胃肠电图测量平均频率(AF)、波形主功率(DP)、波形平均幅值(vpp),HBT测量口-结肠转运时间(oral-colon transit time,OCTT)并进行比较.结果 单因素相关分析显示,摄入乳果糖前后CKD组、对照组0CTT与AF、DP、Vpp呈明显负性相关,差异有统计学意义(P＜0.05).两种方法对胃肠排空延迟、排空正常、排空过速的检出率无显著差别(P＞0.05).CKD组胃肠排空延迟、胃排空过快患者均较对照组明显升高(P＜0.05).结论 CKD组患者普遍存在胃肠功能紊乱.氢呼气试验测定口-结肠转运时间可以作为评估慢性肾脏病患者胃肠动力简便、可靠、安全、可行的方法.