血管紧张素Ⅱ通过抑制AKT/蛋白激酶B磷酸化诱导肾小管上皮细胞凋亡

目的观察血管紧张素Ⅱ(AngⅡ)在诱导肾小管上皮细胞凋亡的信号传导是否有磷脂酰肌醇3激酶(PI3K)-AKT信号系统的参与,及该系统在诱导细胞凋亡中的作用。方法大鼠肾小管上皮细胞株NRK-52E分别与终浓度为0(对照组)、10-9mol/L、10-8mol/L、10-7mol/L、10-5mol/LAngⅡ共培养24h。用流式细胞仪检测细胞凋亡指数,用免疫组化方法检测增殖细胞核抗原(PCNA)的表达。Western印迹检测PI3K及磷酸化AKT和总AKT蛋白表达,AKT的磷酸化水平用473位丝氨酸磷酸化AKT(AKT-ser473)水平与总AKT水平的比值表示。结果随着AngⅡ浓度的增加,10-6mol/LAngⅡ组与对照组相比,凋亡指数显著增加[(22.7±1.41)%比(3.0±0.75)%,P<0.01]。而10-9mol/LAngⅡ组与对照组相比,PCNA指数显著增强[(47.54±2.6)%比(22.63±2.5)%,P<0.01]。与对照组相比,PI3K-p85蛋白的表达随AngⅡ浓度增加表现为先激活后抑制。AKT的磷酸化具有明显的AngⅡ浓度依赖性,随AngⅡ浓度的增加而逐渐受到抑制,并与细胞凋亡指数呈显著负相关(r=-0.90,P<0.01)。结论AngⅡ可以诱导肾小管上皮细胞凋亡并抑制细胞的增殖,可能部分是通过抑制PI3K-AKT信号传导途径实现的。     

辛伐他汀对前列腺上皮细胞RWPE-1增殖及凋亡的影响

目的:探讨辛伐他汀对前列腺上皮细胞RWPE-1增殖及凋亡的影响。方法:设定不同浓度的辛伐他汀(0、10、20、40μmol/L)分别作用于体外培养的RWPE-1细胞,利用MTT法检测细胞增殖情况,流式细胞术检测细胞的凋亡情况。荧光定量RT-PCR检测RWPE-1细胞的Bcl-2、Bax、Cx43 mRNA的表达,Western印迹检测Bcl-2、Bax、Cx43蛋白的表达。结果:MTT法检测辛伐他汀(10、20、40μmol/L)作用于RWPE-1细胞72 h后,对RWPE-1细胞的抑制率分别为(21.07±6.41)%、(34.87±9.65)%和(47.18±10.88)%,与对照组[(1.21±0.54)%]比较有显著差异(P0.05),并且呈明显的剂量依赖关系(P0.05);处理72 h后各组的凋亡指数分别为:10μmol/L组(0.066±0.016)%,20μmol/L组(0.126±0.023)%,40μmol/L组(0.192±0.025)%,与对照组[(0.015±0.005)%]相比差异显著(P0.01),且呈剂量依赖关系(P0.05)。荧光定量PCR检测显示随着辛伐他汀浓度升高Bcl-2基因表达逐渐下调(P0.05),Bax和Cx43基因表达逐渐上调(P0.05),并且呈剂量依赖关系(P0.05)。Western印迹检测显示RWPE-1细胞内Bcl-2蛋白的表达随辛伐他汀浓度的增高逐渐下调(P0.05),Bax蛋白逐渐上调(P0.05),Cx43蛋白逐渐上调(P0.01),并且皆呈剂量依赖关系(P0.05)。Cx43的表达与Bcl-2的表达呈负相关,与Bax的表达呈正相关。结论:辛伐他汀可能通过影响细胞间隙连接通讯来抑制前列腺上皮细胞增殖并诱导其凋亡。     

JNK信号通路在丙泊酚减轻人脐静脉内皮细胞氧化应激损伤中的作用

目的探讨不同浓度丙泊酚预处理对人脐静脉内皮细胞(HUVECs)氧化应激损伤的作用,探讨其与c-Jun氨基端激酶(JNK)信号通路的关系。方法体外培养的HUVECs分为八组:对照组(C1组)细胞行常规培养;DMSO对照组(C2组)细胞的培养基中加入DMSO(终浓度0.05%);丙泊酚组(P组)细胞的培养基中加入丙泊酚(终浓度50μmol/L)处理4h;H2O2处理组(H组)细胞的培养基中加入H2O2(终浓度400μmol/L)处理4h;超低浓度丙泊酚组(HP1组)的细胞以1μmol/L丙泊酚预处理HUVECs 30min后加入H2O2400μmol/L处理4h;余在HP1组基础上增加预处理丙泊酚浓度分别为5μmol/L(HP5组)、25μmol/L(HP25组)和50μmol/L(HP50组)。各组细胞培养后,用CCK-8法测定细胞活力,流式细胞仪检测细胞凋亡情况,Western blot法检测HUVECs磷酸化JNK(p-JNK)、Bcl-2及Bax蛋白表达水平。结果与C1组比较,H组和HP1、HP5、HP25、HP50组细胞活力明显降低,细胞凋亡率明显升高,p-JNK蛋白表达以及Bax蛋白表达明显升高,而Bcl-2/Bax比值明显降低(P0.05);HP1组和HP5组p-JNK/JNK比值明显升高,Bcl-2蛋白表达明显下降(P0.05)。与H组比较,HP25组和HP50组的细胞活力明显升高,HP5组、HP25组和HP50组细胞凋亡率明显降低,p-JNK/JNK和Bax表达明显下调,Bcl-2和Bcl-2/Bax比值明显升高(P0.05)。结论 25μmol/L和50μmol/L浓度的丙泊酚预处理可减轻氧化应激对HUVECs的损伤,其机制与抑制JNK信号通路有关。     

胡黄连苷Ⅱ通过线粒体途径诱导肾癌细胞凋亡的实验研究

目的研究胡黄连苷Ⅱ(picrosideⅡ)对人肾癌ACHN细胞凋亡的影响及作用机制。方法将体外培养的肾癌ACHN细胞分为对照组、不同浓度胡黄连苷Ⅱ(1μg/mL、10μg/mL及100μg/mL)组,采用CCK-8法测定细胞增殖率,采用Hoechst 33258核染色法和Annexin V/PI检测细胞凋亡,采用Western blot法检测肾癌ACHN细胞内Bax及Bcl-2蛋白表达。结果不同浓度的胡黄连苷Ⅱ能抑制肾癌ACHN细胞生长并诱导细胞凋亡,随着胡黄连苷Ⅱ作用浓度的递增,肾癌ACHN细胞凋亡率呈剂量依赖性递增;胡黄连苷Ⅱ作用后,Bax蛋白表达增加,Bcl-2蛋白表达下降。结论胡黄连苷Ⅱ通过改变线粒体凋亡途径中凋亡相关信号分子Bax及Bcl-2的表达,抑制肾癌ACHN细胞增殖并促进细胞凋亡。     

下调PAR基因表达对前列腺癌PC3细胞凋亡及凋亡相关蛋白Bcl-2/Bax的影响

目的:本研究以RNA干扰技术下调PAR(prostate androgen regulated)基因表达,探讨其对前列腺癌PC3细胞增殖、凋亡及其相关蛋白Bcl-2/Bax表达水平的影响。方法:PC3细胞转染靶向PAR基因的siRNA,MTT法检测细胞增殖,用流式细胞术检测细胞凋亡,Western印迹检测Bcl-2和Bax蛋白表达水平。结果:PC3细胞PAR基因表达水平下调,此时处于G2-M期的细胞增加,为(29.95±3.25)%;细胞凋亡率亦明显增加,为(20.61±2.73)%,与对照组比较差异有显著性意义(P<0.01),同时Bcl-2蛋白表达下降,Bax表达水平升高,Bax/Bcl-2比值升高。结论:PAR基因表达下调可诱导细胞G2-M期阻滞和凋亡,其机制为抑制凋亡相关蛋白Bcl-2表达,同时促进Bax表达。     

葛根素抑制吡格列酮诱导的成骨细胞凋亡

目的观察葛根素对吡格列酮诱导的成骨细胞凋亡的影响。方法 MTT法检测不同浓度葛根素(0.01-100μmol/L)和吡格列酮(20μmol/L)作用于MC3T3-E1细胞24 h后细胞增殖活性影响。流式细胞仪测定葛根素和吡格列酮对MC3T3-E细胞凋亡的影响。Western blot检测凋亡相关蛋白Caspase-3、Caspase-8、Bcl-2、Bax的表达情况。结果 1、与对照组相比,吡格列酮组的细胞增殖活性明显下降(P0.05),而0.1-10μmol/L葛根素组细胞增殖活性明显增强(P0.05)。2、与吡格列酮组相比,加入0.1-1μmol/L葛根素后细胞的增殖活性明显增强(P0.05)。3、加入1μmol/L的葛根素后,吡格列酮导致的细胞凋亡率上升受到抑制(P0.05)。4、吡格列酮处理后caspase-3、caspase-8、Bax蛋白的表达上调,Bcl-2蛋白的表达下调,而加入葛根素共同作用后,caspase-3蛋白表达下调,Bcl-2蛋白的表达上调。结论葛根素可以抑制吡格列酮诱导的成骨细胞凋亡。     

ROS/GADD153蛋白在血管紧张素Ⅱ诱导心肌细胞凋亡中的作用

目的 探讨活性氧簇(ROS)/GADD153蛋白在血管紧张素Ⅱ(AngⅡ)诱导心肌细胞凋亡中的作用.方法 体外培养乳鼠心肌细胞,随机分为9组(n=5),Ⅰ组(C组)常规心肌细胞培养,不予其他处理;Ⅱ组(AngⅡ6组)给予100 nmol/L AngⅡ,孵育6 h;Ⅲ组(AnsⅡ12组)给予100 nmol/L AngⅡ,孵育12 h;Ⅳ组(ArtsⅡ24组)给予100 nmol/L Ang Ⅱ,孵育24 h;V组[N-乙酰-L半胱氨酸(NAC)+AngⅡ组]预先给予抗氧化剂NAC 5 mmol/L,2 h后给予100 nmol/L Ang Ⅱ,孵育24 h;Ⅵ组(NAC组)仅给予NAC 5 mmol/L,孵育24 h;Ⅶ组(anti-ODN组)GADD153反义寡核苷酸10 μmol/L转染24 h后,加入100nmoFL AngⅡ,孵育24 h;Ⅷ组(mis-ODN组)GADDl53错义寡核苷酸10 μmol/L转染24 h后,加入100nmol/L Ang Ⅱ,孵育24 h;Ⅸ组(脂质体对照组)加入等容量转染试剂,孵育24 h.检测细胞活力、细胞内ROS产量、细胞凋亡率及GADD153蛋白表达水平.结果 与C组相比,AngⅡ6组、AngⅡ12组、AngⅡ24组细胞活力降低,细胞凋亡率、ROS产量及GADD153蛋白表达升高,且呈时间依赖性(P＜0.05);与AngⅡ24组比较,NAC+AngⅡ组和anti-ODN组细胞活力升高,细胞凋亡率、ROS产量及GADD153蛋白表达降低(P＜0.05).结论 AugⅡ通过增加ROS产量,诱导GADD153蛋白表达上调,从而导致心肌细胞凋亡的发生.     

低氧对大鼠睾丸生殖细胞凋亡的影响

目的:研究低氧对大鼠睾丸生殖细胞凋亡和Bax、Bcl-2表达的影响。方法:雄性成年Wistar大鼠随机分为4组:常氧对照组、低氧5 d组、低氧15 d组和低氧30 d组(各组n=6)。常氧对照组在平原喂养;低氧5 d组、15 d组和30 d组分别在低压舱内模拟5 000 m高原喂养5、15、30 d。采用流式细胞术和TUNEL法检测低氧对睾丸生殖细胞凋亡的影响。运用Western印迹技术检测低氧对大鼠睾丸内凋亡相关蛋白Bax、Bcl-2表达的影响。结果:低氧5 d组、15 d组和30 d组睾丸内发生生殖细胞凋亡的生精小管数量[每100个生精小管中,含有凋亡生殖细胞的生精小管数分别为(20.50±5.07)、(21.25±7.85)、(14.00±2.45)个]均非常显著地高于常氧对照组[(6.00±2.16)个,P<0.01]。凋亡的生殖细胞以精原和精母细胞为主。低氧15 d组睾丸组织亚单倍体细胞百分率[(2.18±0.82)%]显著高于常氧对照组[(1.30±0.33)%,P<0.05],低氧30 d组[(3.08±0.93)%]极显著高于常氧对照组(P<0.01)。低氧30 d组睾丸组织Bax表达显著高于常氧对照组(P<0.05),其灰度值分别为17.34±4.54和10.50±2.82。低氧30 d组睾丸组织Bax/Bcl-2比值显著高于常氧对照组(P<0.01),比值分别为0.40±0.10和0.27±0.04。结论:低氧诱导大鼠睾丸生殖细胞凋亡增多,慢性低氧引起的睾丸生殖细胞凋亡增多与Bax表达增加有关。     

TRPC6高表达对血管紧张素Ⅱ诱导的小鼠足细胞凋亡的影响

目的 观察瞬间受体电位阳离子通道蛋白6(TRPC6)高表达对血管紧张素Ⅱ(AnglI)诱导的小鼠足细胞凋亡的影响并探讨其作用机制.方法 用脂质体将针对小鼠TRPC6的基闪真核表达载体pEGFP.N1.mTRPC6转染体外培养的永生化小鼠足细胞系.24 h后用荧光显微镜观察增强绿色荧光蛋白(EGFP)的表达.Western印迹法检测转染后TRPC6蛋白表达的变化.将足细胞分组,应用不同浓度AngⅡ处理足细胞,Fluo-3AM结合激光共聚焦显微镜检测各组足细胞胞质内钙离子的浓度.RT-PCR及Westem印迹法检测Bax、Bcl-2 mRNA及蛋白的水平.流式细胞仪及Hoeehst染色法榆测足细胞凋亡.结果 pEGFP-NI-mTRPC6转染足细胞后,约35%细胞出现绿色荧光;足细胞TRPC6蛋白表达明显上调(P<0.01).TRPC6高表达町以明显促进AngII诱导的足细胞钙离子内流(P<0.01),在蛋白及基因水平均上调Bax的表达而下调Bcl.2的表达(P<0.01,P<0.05).在低剂量Ang Ⅱ(10-10mol/L)作用下.足细胞凋亡率为(2.50±0.72)%,转染TRPC6以后凋亡率为(4.33±0.45)%,差异有统计学意义(P<0.05).在高剂量Ang Ⅱ(10-6mol/L)作用下,足细胞凋亡率为(15.46±1.40)%.转染TRPC6以后凋亡率为(18.33±0.87)%,差异有统计学意义(P<0.01).结论 TRPC6在AngⅡ诱导的足细胞凋亡中发挥重要作用.TRPC6可能通过增加钙离子内流,进而启动其下游的捌亡调节成分参与凋亡过程.     

槲皮素对前列腺癌PC-3细胞凋亡作用的研究

目的:研究槲皮素对人前列腺癌PC-3细胞的凋亡作用。方法:体外培养PC-3细胞,给予不同浓度(50、100、150、200、250μmol/L)的槲皮素处理,MTT法检测槲皮素对细胞抑制率;流式细胞仪检测细胞凋亡率;透射电镜观察细胞超微结构的变化。结果:槲皮素能抑制人前列腺癌PC-3细胞的体外生长,且呈时间与剂量依赖性,浓度由低到高,其24 h的抑制率(%)分别为3.01±1.32、4.84±1.73、20.35±1.30、16.78±1.89、27.25±4.01,48 h的抑制率(%)分别为10.18±1.16、6.22±0.04、24.29±4.19、22.4±4.26、41.42±5.43,当药物浓度>150μmol/L时P<0.05,具有统计学意义;流式细胞术显示PC-3细胞凋亡率随槲皮素浓度升高和作用时间延长而增加(P<0.05),其中浓度150μmol/L和200μmol/L组,24 h的凋亡率(%)分别19.10±0.28、26.55±0.78,48 h的凋亡率(%)分别为27.65±1.06、38.30±5.96;电镜观察到细胞的典型凋亡形态学变化。结论:在适当的条件下,槲皮素对人前列腺癌PC-3细胞增殖有明显的抑制作用,同时可诱导PC-3细胞凋亡,其具体作用机制有待进一步深入研究。     

Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep

AIMS: To understand their possible importance in long- and short-term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics. MATERIALS AND METHODS: Striated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation. RESULTS: All muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued. CONCLUSIONS: Both the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long-term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained.     

Recognition and management of phaeochromocytoma and paraganglioma

Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours arising from the chromaffin cells in the adrenal medulla. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in perioperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications.     

Instrumented ligamentotaxis and stabilization of compression and burst fractures of dorsolumbar and mid-lumbar spines

Background:

Controversy continues regarding the best treatment for compression and burst fractures. The axial distraction reduction utilizing the technique employing the long straight rod or curved short rod without derotation to reduce fracture are practised together with short segment posterolateral fusion (PLF). Effects of the early postoperative mobilization without posterolateral fusion on reduction maintenance and fracture consolidation were not evaluated so far. The present prospective study is designed to assess the effectiveness of i) reduction and restoration of sagittal alignment, ii) no posterolateral fusion on the reduced, fractured vertebral body and injured disc, iii) fracture consolidation and iv) the fate of the unfused cephalad and caudal injured motion segments of the fractured vertebra.

Materials and Methods:

The study includes 15 Denis burst and two Denis type D compression fractures between T₁₂ and L₃. The lordotic distraction technique was used for ligamentotaxis utilizing the contoured short rods and pedicle screw fixator. Three vertebrae including the fractured one were fixed. The patients after surgery were braced for ten weeks with activity restriction for 2-4 weeks. The patients were evaluated for change in vertebral body height, sagittal curve, reduction of retropulsion, improvement in neural deficit. The unfused motion segments, residual postoperative pain and bone and metal failure were also evaluated.

Results:

The preoperative and postreduction percentile vertebral heights at, zero (immediate postoperative), at three, six and 12 months followup were 62.4, 94.8, 94.6, 94.5 and 94.5%, respectively. The percentages of the intracanal fragment retropulsion at preoperative, and postoperative at zero, 3, 6 and 12 months followup were 59.0, 36.2,, 36.0, 32.3, and 13.6% respectively.The preoperative and postreduction percentile loss of the canal dimension and at zero, three, six and 12 months were 52.1, 45.0, 44.0, 41.0 and 29% respectively suggesting that the under-reduced fragment was being resorbed gradually by a remodeling process. The mean initial kyphosis of 33° became mean 2° immediately after reduction and mean 3° at the final followup. The fractured vertebral bodies consolidated in an average period of ten weeks (range 8-14 weeks). The restored disc heights were relatively well maintained throughout the observation period. All paraparetic patients recovered neurologically. There were no postoperative complications.

Conclusion:

Instrument-aided ligamentotaxis for compression and burst fractures utilizing the short contoured rod derotation technique and the instrumented stabilization of the fractured spine are found to be effective procedures which contribute to the fractured vertebral body consolidation without recollapse and maintain the motion segment function.     

Incorporation and release of85Sr and14C-proline-hydroxyproline in mineral and collagen of bone and incisor teeth of growing rats

The extent to which exchange and reutilization processes of mineral tracers affect skeletal mineral accretion and resorption measurements was evaluated by comparing the rates of appearance and disappearance of⁸⁵Sr and¹⁴C-proline-hydroxyproline in bones and teeth in growing rats for 12 days following simultaneous parenteral injection of these tracers. Expressions for the relative rates of collagen synthesis and breakdown, which unlike mineral metabolism are considered not to be complicated by exchange phenomena, were based on¹⁴C-proline conversion to¹⁴C-hydroxyproline; the specific activity of the latter was determined. Both the mineral and the collagen specific activities reflected the rates and patterns of growth of the samples assayed; rapid growth and a short interval of time between formation and resorption of tissue in themetaphyseal bone which contains the cartilagineous growth plate, slow growth and an interval of time between formation and resorption of tissue indiaphyseal bone and incisor teeth which is longer than the 12 days of the experiment. However, in metaphyseal bone the specific activity collagen/mineral ratio dropped by one half during the 4–12 day interval in contrast to diaphyseal bone and incisor teeth in which no change in this ratio was observed during this period of time. The data indicate that collagen in the metaphyseal growth zone is removed by resorption before it has become fully mineralized, and that exchange is a relatively unimportant factor in the long term kinetics of bone mineral.

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Zusammenfassung Das Ausmaß, bis zu welchem Austausch- und Wiederverwendungsprozesse der mineralen Tracer die Messungen des mineralen Skelett-Auf- und Abbaues beeinflussen können, wurde ausgewertet; zu diesem Zweck wurde die Geschwindigkeit des Auftretens und Verschwindens von⁸⁵Sr und von¹⁴C-Prolin-Hydroxyprolin in Knochen und Zähnen von wachsenden Ratten während der 12 auf die simultane parenterale Injektion dieser Tracer folgenden Tage verglichen.Der Ausdruck für die relative Geschwindigkeit des Kollagen-Auf- und Abbaues, bei welchem im Gegensatz zum Mineralmetabolismus kein Mitwirken des Austauschphänomens vermutet wird, basiert auf der Umwandlung von¹⁴C-Prolin zu¹⁴C-Hydroxyprolin; die spezifische Aktivität des letzteren wurde bestimmt.Aus der spezifischen Aktivität des Minerals sowie jener des Kollagens konnten die Geschwindigkeit und die Art des Wachstums der untersuchten Proben ersehen werden, d.h.schnelles Wachstum und ein kurzes Zeitintervall zwischen Bildung und Resorption des Gewebes imKnochen der Metaphyse, die auch die knorpelige Wachstumsplatte enthält, und andererseitslangsames Wachstum und längeres Zeitintervall (länger als die 12 Tage des Experimentes) zwischen Bildung und Resorption des Gewebes imKnochen der Diaphyse und in den Schneidezähnen. Immerhin fiel die spezifische Aktivität des Kollagen/Mineral-Anteils im Knochen der Metaphyse während dem 4–12tägigen Zeitintervall auf die Hälfte, im Gegensatz zum Knochen der Diaphyse und der Schneidezähne, bei welchen während dieser Zeitspanne kein Unterschied in diesem Verhältnis beobachtet wurde.Diese Ergebnisse zeigen, daß Kollagen in der Wachstumszone der Metaphyse durch Resorption verschwindet, bevor es ganz mineralisiert ist, und daß der Austausch ein relativ unwichtiger Faktor in der Kinetik auf lange Sicht des Knochenminerals ist.

     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist and nabilone, a synthetic cannabinoid.     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist, and nabilone, a synthetic cannabinoid.     

动静脉穿刺网络课件的开发及其应用

目的:确保护理教学效果,提高教学水平。方法:应用多项信息技术将动静脉穿刺技术制作成教学网络课件,并用于临床教学。结果:该课件在本校园网上运行半年余,2000余人次对其进行访问,受到师生好评。结论:该课件能及时反映动静脉穿刺的最新研究进展及具体操作步骤和使用方法,实现护理教学的直观性和交互性,对护理教学和临床带教指导有一定的借鉴作用。     

Physiology and pharmacology of nausea and vomiting

The physiology of nausea and vomiting is poorly understood. The initiation of vomiting varies and may be due to motion, pregnancy, chemotherapy, gastric irritation or postoperative causes. Once initiated, vomiting occurs in two stages, retching and expulsion. The muscles responsible for this sequence of events are controlled by either a vomiting centre or a central pattern generator, probably in the area postrema and the nearby nucleus tractus solitarius. Drugs which induce vomiting include ipecacuanha, a gastric irritant, and apomorphine, a dopamine-receptor agonist. Opioid drugs also induce vomiting, but opioid antagonists are not useful to treat nausea and vomiting. Anti-emetic drugs consist of a variety of neurotransmitter antagonists and may act in the periphery, the central nervous system or both sites. The most important drugs are antagonists at muscarinic, dopamine D₂, 5-HT₃, histamine H₁ and neurokinin NK₁ receptors. These drugs are discussed with particular attention to post-operative nausea and vomiting (PONV).