何首乌致肝损伤大鼠的动态血清代谢组学研究

该文采用液相色谱-质谱方法测定服用何首乌大鼠的血清代谢指纹谱,同时利用多元统计分析方法比较代谢谱差异并筛查显著相关的生物标志物,考察其动态变化趋势。探讨何首乌致大鼠肝脏损伤的代谢组学动态变化,寻找其显著相关的生物标志物,并考察标志物的动态变化趋势,以期为何首乌致肝损伤的内在机制与临床早期诊断提供依据。结果显示给药后不同时间点大鼠的血清代谢轮廓存在一定的差异,经比较分析,共筛选得到6个潜在生物标志物:oleamide,lyso PC(16∶0),leukotriene A4,trans-tetra-dec-2-enoic acid,dihydrocortisol和7a-hydroxydehydroepiandrosterone,这些标志物在何首乌致肝损伤动态过程中呈现一定的变化趋势。所筛选到的生物标志物在给药1周后含量即出现明显变化,相比于ALT,AST来说更加敏感。一定程度上可揭示出何首乌造成肝损伤的动态机制以及肝脏自我修复表现,对于监测服用何首乌患者肝功能、早期发现何首乌肝损伤具有潜在的应用价值和意义。     

参芎葡萄糖注射液对H2O2诱导的HUVEC细胞氧化损伤的保护作用

目的:探讨参芎葡萄糖注射液(Shenxiong glucose injection,SGI)对H_2O_2诱导的人脐静脉上皮细胞(HUVEC)细胞氧化模型损伤的保护作用及其机制。方法:体外培养HUVEC人脐静脉内皮细胞,用H_2O_2(130 mmol·L~(-1))处理0.5 h,建立HUVEC细胞H_2O_2氧化损伤模型。SGI组HUVEC细胞用(6%,8%,10%)SGI预处理6 h后,再用H_2O_2处理0.5 h。用MTS法检测细胞存活率;用ELISA法检测乳酸脱氢酶(LDH)漏出量、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)活力;用实时荧光定量聚合酶链式反应(Real-time PCR)和蛋白质免疫印迹(Western blot)技术检测凋亡相关基因及蛋白B细胞淋巴瘤/白血病-2(Bcl-2),Bcl-2相关X蛋白(Bax)和半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)的mRNA和蛋白表达情况。结果:在130 mmol·L~(-1)H_2O_2作用细胞0.5 h的情况下,细胞存活率降低至50%左右,降低的程度合适,且实验结果重复性好,因此后续实验用该条件建立氧化损伤模型。与H_2O_2组比较,SGI预处理6 h能显著升高细胞存活率(P0.05,P0.01),减少LDH的外漏和MDA的生成(P0.05,P0.01),显著增加SOD,GSH-Px和CAT的活性(P0.05,P0.01)。RT-PCR和Western blot结果表明,SGI能显著上调Bcl-2的表达(P0.05,P0.01),下调Caspase-3,Bax的表达(P0.05,P0.01)。结论:参芎葡萄糖注射液能保护HUVEC细胞对抗H_2O_2诱导的氧化损伤,具有一定的剂量依赖关系,其作用机制可能与抑制细胞凋亡有关。     

从自噬角度研究雷公藤甲素引起HepG2细胞肝毒性的机制

目的:探讨雷公藤甲素(TP)对HepG2细胞的过氧化损伤及对自噬的调控作用。方法:将质量浓度为0.003 2,0.016,0.08,0.4,2 g·L~(-1)的TP作用于体外培养的HepG2细胞48 h,另设空白组做对比,采用噻唑蓝(MTT)法检测细胞生长活性,采用酶联免疫吸附测定(ELISA)法检测超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH-Px)的活性,采用蛋白质免疫印迹(Western blot)法检测自噬相关蛋白微管相关蛋白轻链3(LC3Ⅱ)与Beclin1蛋白的表达情况,用免疫荧光法检测自噬相关蛋白LC3的表达情况。结果:与空白组比较,随着TP质量浓度的增加,HepG2活性下降(P0.05,P0.01);检测细胞上清中SOD,GSH-Px的活性,均较空白组降低(P0.05,P0.01);Western blot表明TP可上调LC3Ⅱ与Beclin1蛋白水平的表达(P0.05,P0.01),免疫荧光法同样表明TP能够引起自噬相关蛋白LC3表达的增多(P0.05,P0.01),均具有一定的浓度依赖性。结论:一定质量浓度的TP可造成肝细胞损伤,其损伤机制可能与过氧化损伤以及过氧化损伤导致的自噬过度激活有关。     

Chlorhexidine induces DNA damage in rat peripheral leukocytes and oral mucosal cells

OBJECTIVE: Chlorhexidine digluconate is widely used in dental practice for decreasing plaque control, controlling gingivitis and disinfecting root canals. However, the undesirable effects of chlorhexidine digluconate regarding its genotoxicity are conflicting in the literature. Thus, the aim of this study was to investigate the genotoxicity of chlorhexidine digluconate in rat peripheral blood and oral mucosal cells by the single cell gel (comet) assay and micronucleus assay. METHODS: Thirty male Wistar rats were distributed into three groups: negative control; experimental group orally treated with 0.5 ml of 0.12% chlorhexidine digluconate, twice daily, during 8 days; and positive control, which received 4-nitroquinoline 1-oxide at 0.5 g/l by drinking water. RESULTS: A statistically significant increase of DNA damage was observed in leukocytes and oral mucosal cells of the chlorhexidine digluconate treated group, as assessed by the comet assay. However, no increase of micronucleated cells was detected in reticulocytes from peripheral blood cells. CONCLUSIONS: Taken together, the data indicate that chlorhexidine digluconate is able to induce primary DNA damage in leukocytes and in oral mucosal cells, but no chromosome breakage or loss in erythrocytes.     

Fatigue and damage to the masseter muscle by prolonged low-frequency stimulation in the rat

This study aimed to examine peripheral fatigue and the resultant damage to the masseter muscle due to prolonged low-frequency stimulation. Thirty male rats were divided into S1, S2, S4, Dantr and Sham groups. The left masseters were used as experimental muscles. A pair of stimulation electrodes was placed on the left masseter. A stimulating session included rectangular electric pulses of 18 Hz (5 mA, 18 V, 0.7 ms) for 2 h with a 3 min rest period between sessions. One session was given to the S1 group, two sessions to the S2 group and four sessions to the S4 group. Four sessions were given to the Dantr group with administration of dantrolene to determine any artifacts of the electrical current. No electric stimulation was given to both side masseters in the Sham group or to the control (right) masseters in the other groups. In each session, jaw-closing force increased to a peak within 1 min and attenuated to the steady force. The peak force decreased as the session advanced in each group. Both side masseters were dissected after the stimulations and examined histologically. The experimental masseter was significantly heavier than that of the controls in the S1, S2 and S4 groups, and the muscle fibres showed irregularity of size and shape with enlargement of interstitial space and infiltration of mononuclear cells into the fibres. However, no such histological change was observed in the Dantr and Sham groups. It was confirmed that fatigue and damage to muscle fibres could be induced in masticatory muscles by prolonged low-frequency stimulation.     

超声龈下刮治对根面影响的扫描电镜研究

目的 研究不同功率超声龈下刮治对根面的影响。方法 选择因重度牙周炎需拔除的患牙12颗，随机分成小功率超声刮治组、大功率超声刮治组、手工刮治组及病变对照组四个组，每组3颗。记录刮治时间，扫描电镜观察各组标本的菌斑、牙石残留及损伤情况。结果 大功率超声刮治效率最高、最省时，小功率次之，手工刮治最慢；大功率超声刮治对根面损伤最大，小功率超声刮治损伤轻微，手工刮治损伤最小。结论 超声龈下刮治能有效地去除根面的菌斑、牙石，且省时、省力，但功率不宜过大。     

Root contact during insertion of miniscrews for orthodontic anchorage increases the failure rate: an animal study

OBJECTIVES: Miniscrews and miniplates are increasingly being used for absolute anchorage during orthodontic treatment. However, potential problems of damaging adjacent roots and their consequences during mini-implant placement in the alveolar process have not been clearly described. MATERIALS AND METHODS: Animal experiments were used to evaluate the stability of miniscrews placed with intentional root contact. The root repair was evaluated after screw removal. Seventy-two miniscrews were surgically placed in the mandibular alveolar bone of six adult mongrel dogs with metabolic bone labeling at 3-week intervals. Miniscrews of the experimental group were placed so that they contacted the root of the adjacent teeth, were retained for different time durations, and were then removed. The insertion torque, clinical measurements, removal torque, and histological findings were analyzed. RESULTS: (1) miniscrews contacting the roots showed a significantly higher insertion torque than those without contact; (2) there was a significant difference in the removal torque measurements based on the mobility of miniscrews and the state of root contact; and (3) miniscrews contacting the root were at greater risk of failure. CONCLUSIONS: During placement of miniscrews in the aveolar process, increased failure rates were noticed among those contacting adjacent roots. Failed miniscrews appeared to be surrounded with a greater volume of soft tissue. When more inflammation was present, the adjacent roots seemed to experience more resorption. Nevertheless, the created lesion was repaired with a narrow zone of mineralized tissue deposited on the root surface, which was likely cellular cementum, and was mainly filled with alveolar bone, with the periodontal ligament space being maintained.     

Increased oxidative stress and damage in patients with chronic bacterial prostatitis

Objective To investigate whether chronic bacterial prostatitis （CBP） increases oxidative stress and damage in patients with CBP, and to explore its possible mechanism. Methods Eighty patients with CBP and 80 healthy adults as controls were enrolled in a case-control study, in which levels of nitric oxide （NO）, vitamin C （VC）, and vitamin E （VE） in plasma, as well as malondialdehyde （MDA）, activities of superoxide dismutase （SOD）, and eatalase （CAT） in erythrocytes were determined by spectrophotometry. Results Compared with the average values of NO, VC, VE, MDA, SOD, and CAT in the healthy control group, those of plasma N O and erythrocyte MDA in the CBP group were significantly increased （P〈0.00 1）, and those of plasma VC and VE as well as erythrocyte SOD and CAT in the CBP group were significantly decreased （P〈0.001）. Findings from partial correlation analysis for course of the disease and NO, VC, VE, MDA, SOD, and CAT in 80 patients with CBP, adjusted for age, suggested that with prolonged course of the disease, values of NO and MDA were gradually increased （P〈0.001）, and those of VC, VE, SOD, and CAT were gradually decreased （P〈0.05-0.001）. The findings from stepwise regression analysis for course of the disease and NO, VC, VE, MDA, SOD, and CAT in CBP group suggested that the model of stepwise regression was Y = -19.1160 ＋0.3112MDA ＋ 0.0337NO, F = 22.1734, P〈0.001, r = 0.6045, P〈0.001. The findings from the reliability analysis for VC, VE, SOD, CAT, NO, and MDA in the CBP group showed that the reliability coefficients＇ alpha （6 items） was 0.7195, P〈0.0001, and the standardized item alpha was 0.9307, P〈0.0001. Conclusion There exist increased oxidative stress and damage induced by chronic bacterial prostatitis in patients, and such a phenomenon is closely related to the course of disease.     

谷氨酸钠的安全性研究进展

谷氨酸钠是一种氨基酸的钠盐,大量摄入时,会导致血液谷氨酸浓度显著上升,可引起一系列有害影响.谷氨酸钠高暴露可干扰下丘脑的信号传导和瘦素功能,引起机体出现代谢综合征症状,母体高暴露可致新生儿出现代谢紊乱,新生儿期高暴露可致成年代谢综合征.谷氨酸钠还可诱导神经兴奋毒性,引起化学性脑损伤;以剂量依赖的方式损害男性生殖系统,通过损伤卵巢和子宫的功能来抑制雌性生殖功能;通过改变肾脏抗氧化系统损伤肾细胞和肾功能.本文对谷氨酸钠的安全性研究进展进行综述.     

原发性高血压中期肾损害患者的中医脏腑辨证特点及临床意义

目的 探讨原发性高血压中期肾损害患者的中医脏腑辨证特点及临床意义,为患者临床诊疗提供相关指导。方法 选取2019年9月至2020年8月我院接收诊治的320例原发性高血压患者为研究对象。根据其肾损害情况,将所有患者分为对照组(无肾损害,172例)和研究组(中期肾损害,148例)。对比两组患者中医脏腑辨证特点,并比较研究组患者不同年龄段、不同高血压级别的中医脏腑辨证特点。结果 对照组患者的肝脏证候积分为(3.51±0.64)分,明显高于研究组的(1.97±0.43)分,研究组患者的肾脏、脾脏证候积分分别为(2.97±0.62)分、(2.77±0.57)分,均明显高于对照组的(2.34±0.54)分、(2.25±0.54)分,差异均有统计学意义(P0.05);对照组患者的阳亢证证候积分为(2.43±0.47)分,明显高于研究组的(1.28±0.31)分,研究组患者的气虚证、阴虚证证候积分分别为(2.72±0.55)分、(1.93±0.41)分,均明显高于对照组的(2.21±0.47)分、(1.35±0.32)分,差异均有统计学意义(P0.05);70岁患者的肾脏证候积分为(4.28±0.76)分,气虚证、阴虚证、血瘀证证候积分分别为(4.05±0.71)分、(2.33±0.45)分、(1.87±0.35)分,均明显高于其他三个年龄段,差异均有统计学意义(P0.05);3级高血压患者的肾脏、脾脏证候积分分别为(4.63±0.77)分、(3.15±0.39)分,气虚证、阴虚证、血瘀证证候积分分别为(4.33±0.75)分、(2.94±0.37)分、(1.59±0.18)分,均明显高于1级和2级高血压患者,差异均有统计学意义(P0.05)。结论 原发性高血压中期肾损害患者的中医脏腑辨证病位为肾脏、脾脏,病性为气虚证、阴虚证及血瘀证;患者年龄越大、高血压级别越高,其肾脏、脾脏损害越严重,气虚证、阴虚证及血瘀证程度加重。