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1.
Electropermeabilization/electroporation (EP) provides a tool for the introduction of molecules into cells and tissues. In electrochemotherapy (ECT), cytotoxic drugs are introduced into cells in tumors, and nucleic acids are introduced into cells in gene electrotransfer. The normal and tumor tissue blood flow modifying effects of EP and the vascular disrupting effect of ECT in tumors have already been determined. However, differential effects between normal vs. tumor vessels, to ensure safety in the clinical application of ECT, have not been determined yet. Therefore, the aim of our study was to determine the effects of EP and ECT with bleomycin on the HT-29 human colon carcinoma tumor model and its surrounding blood vessels. The response of blood vessels to EP and ECT was monitored in real time, directly at the single blood vessel level, by in vivo optical imaging in a dorsal window chamber in SCID mice with 70 kDa fluorescently labeled dextrans. The response of tumor blood vessels to EP and ECT started to differ within the first hour. Both therapies induced a vascular lock, decreased functional vascular density (FVD) and increased the diameter of functional blood vessels within the tumor. The effects were more pronounced for ECT, which destroyed the tumor blood vessels within 24 h. Although the vasculature surrounding the tumor was affected by EP and ECT, it remained functional. The study confirms the current model of tumor blood flow modifying effects of EP and provides conclusive evidence that ECT is a vascular disrupting therapy with a specific effect on the tumor blood vessels.  相似文献   

2.
Electroconvulsive therapy (ECT) is known to stimulate subcortical brain regions and release hormones from the anterior and the posterior pituitary. To enhance the subcortical effect of ECT and the neuroendocrinological response we used high dose right unilateral ECT (RUL-ECT) in 11 depressive patients and studied its effect on the release of vasopressin, prolactin and neuropeptide FF. The RUL ECT stimulus for all studied patients was 5 times the individual seizure threshold and it led to immediate release of vasopressin in all studied patients. The release of prolactin was less uniform however in accordance with results from earlier studies. The ECT also stimulated a NPFF secretion peak that came approximately 5 min after ECT stimulus and preceded the prolactin peak. The maximal elevations in circulating vasopressin and prolactin concentrations were 680% and 950%, respectively. The neuropeptide FF concentration increased by 100% after ECT. There was a second rise in NPFF concentration at 25 min after the ECT treatment. The increases in all peptide concentrations were significant, but were not correlated with each other. The neuropeptide FF concentration returned to baseline level at 10 min and the vasopressin concentration at 25 min after ECT. The prolactin concentration remained increased during the 30 min follow up period. Our results complete earlier finding on ECT stimulated vasopressin and prolactin release and show that high intensity RUL-ECT releases neuropeptide FF into human blood. The modest rise of circulating NFFF most likely represents leakage from the CNS.  相似文献   

3.
施肥对短枝木麻黄幼苗总酚和可溶性缩合单宁含量的影响   总被引:1,自引:0,他引:1  
Zhang LH  Lin YM  Ye GF 《应用生态学报》2010,21(8):1959-1966
研究了施用氮肥和磷肥对短枝木麻黄幼苗总酚(total phenolics,TP)和可溶性缩合单宁(extractable condensed tannin,ECT)含量的影响,探讨短枝木麻黄单宁形成的养分效应.结果表明:施加氮肥使短枝木麻黄幼苗小枝的TP和ECT含量显著降低,支持碳氮平衡假说和生长分化平衡假说,但对氮含量没有显著影响,从而导致TP/N和ECT/N降低;施加磷肥对TP和ECT含量没有显著影响;随着处理时间的延长,短枝木麻黄幼苗小枝TP含量升高了9.91%~14.32%,而ECT含量降低了14.32%~298.88%;TP或ECT与有机物质含量的关系则相反,表明不同类型单宁的合成途径不同,但由于TP和ECT均与氮含量无显著相关性,故不支持蛋白质竞争模型;在贫瘠土壤条件下,TP/N和ECT/N的水平较高,有利于提高短枝木麻黄的防御水平,降低凋落物的分解率,减少养分损失,从而保持较高的生产力.  相似文献   

4.
目的:观察电休克对大鼠空间记忆和海马磷酸化细胞外调节蛋白激酶(p-ERK)活性的影响。方法:大鼠随机分为电休克组和伪电休克组,每组12只。电休克组每天给予电痉挛刺激,伪电休克组每天给予假电痉挛刺激,共10天;第11天用水迷宫检测各组大鼠的空间学习记忆,然后每组大鼠再随机分为两组,每组6只。一组于学习后1小时处死取海马用Western blot法检测p-ERK活性,另一组于48小时后行水迷宫空间位置探寻实验检测大鼠的存储记忆。结果:电休克组的潜伏期显著长于伪电休克组(P0.01)。电休克组在隐匿平台周围区域/相反区域的搜寻时间无显著性差异(P0.05);伪电休克组在隐匿平台周围区域/相反区域的搜寻时间有显著性差异(P0.05)。电休克组海马p-ERK活性较伪电休克组显著下降(P0.01)。结论:电休克可导致大鼠显著空间记忆障碍,海马p-ERK活性的降低可能是其机制之一。  相似文献   

5.
成敬  李承晏  王高华  陈振华  肖玲 《生物磁学》2013,(27):5230-5233
目的:研究石杉碱甲对电休克模型大鼠记忆和海马活性调节的细胞骨架联合基因(Activity-regulatedcytoskeletal—associatedgene,ARC)表达的影响。方法:大鼠随机分为假电休克对照组和电休克组,再随机分为生理盐水对照组(CS组、ES组)和石杉碱甲组(CH组、EH组)。第l-17天行生理盐水或石杉碱甲灌胃;第8—17天给予假电痉挛刺激或电痉挛刺激;第18天水迷宫定位航线实验;然后各组大鼠随机分成两组,一组取海马用RT.PCR检测ARCmRNA表达,Westem--blot法检测ARC蛋白表达水平,一组于48小时后行水迷宫空间位置探寻实验。结果:电休克导致大鼠显著记忆障碍,ARCmRNA、ARC蛋白表达水平较假电休克对照组显著下降;而石杉碱甲干预的电休克大鼠记忆保持较好,ARCmRNA、ARC蛋白表达水平显著高于生理盐水干预的电休克大鼠,与假电休克大鼠相比无显著性差异。结论:石杉碱甲能减轻电休克模型大鼠记忆损害,其机制可能与海马ARC的表达增加有关。  相似文献   

6.
Ectoine (ECT) is an amino acid produced and accumulated by halophilic bacteria in stressful conditions in order to prevent the loss of water from the cell. There is a lack of knowledge on the effects of ECT in heat-stressed aquatic animals. The purpose of our study was to determine the influence of ECT on Daphnia magna subjected to heat stress with two temperature gradients: 1 and 0.1 °C/min in the range of 23–42 °C. Time to immobilisation, survival during recovery, swimming performance, heart rate, thoracic limb movement and the levels of heat shock protein 70 kDa 1A (HSP70 1A), catalase (CAT) and nitric oxide species (NOx) were determined in ECT-exposed and unexposed daphnids; we showed protective effects of ECT on Daphnia magna subjected to heat stress. Time to immobilisation of daphnids exposed to ECT was longer when compared to the unexposed animals. Also, survival rate during the recovery of daphnids previously treated with ECT was higher. ECT significantly attenuated a rapid increase of mean swimming velocity which was elevated in the unexposed daphnids. Moreover, we observed elevation of thoracic limb movement and modulation of heart rate in ECT-exposed animals. HSP70 1A and CAT levels were reduced in the presence of ECT. On the other hand, NOx level was slightly elevated in both ECT-treated and unexposed daphnids, however slightly higher NOx level was found in ECT-treated animals. We conclude that the exposure to ectoine has thermoprotective effects on Daphnia magna, however their mechanisms are not associated with the induction of HSP70 1A.  相似文献   

7.
Nutrient, water, and their interactions influence the allocation of investment by plants to resistance and tolerance traits. We used a completely crossed randomized-block design experiment to examine the independent and interactive effects of nutrients and water availability on tannin production of C. equisetifolia seedlings. The results showed that nitrogen and phosphorus fertilizer have significant effects on total phenolics (TP) and extractable condensed tannins (ECT) concentrations of branchlets. TP and ECT concentrations decreased with fertilizer addition and increased in arid condition. This pattern lends to support source-sink hypothesis such as the carbon-nutrient balance (CNB) hypothesis and the growth-differentiation balance (GDB) hypothesis. Soluble sugars or starch concentrations were both inversely related to TP concentrations. However, there was no significant correlation between them and ECT concentrations. In addition, chlorophyll concentration had a positive linear correlation with TP and no significant correlation with ECT. On the contrary, chlorophyll a/b ratios were negatively correlated with TP and positively correlated with ECT. The discrepancy of relationship between carbohydrates and TP or ECT showed that the biosynthetic routes of different tannins were different. In this study, no significant correlation between TP and N, or ECT and N, did not support protein competition model (PCM). TP:N and ECT:N ratios were higher in nutrient deficiency and arid conditions, which were one of the important nutrient conservation strategies for C. equisetifolia.  相似文献   

8.

Background

Many patients have serious depression that is nonresponsive to medications, but refuse electroconvulsive therapy (ECT). Early research suggested that isoflurane anesthesia may be an effective alternative to ECT. Subsequent studies altered drug, dose or number of treatments, and failed to replicate this success, halting research on isoflurane''s antidepressant effects for a decade. Our aim was to re-examine whether isoflurane has antidepressant effects comparable to ECT, with less adverse effects on cognition.

Method

Patients with medication-refractory depression received an average of 10 treatments of bifrontal ECT (n = 20) or isoflurane (n = 8) over 3 weeks. Depression severity (Hamilton Rating Scale for Depression-24) and neurocognitive responses (anterograde and retrograde memory, processing speed and verbal fluency) were assessed at Pretreatment, Post all treatments and 4-week Follow-up.

Results

Both treatments produced significant reductions in depression scores at Post-treatment and 4-week Follow-up; however, ECT had modestly better antidepressant effect at follow-up in severity-matched patients. Immediately Post-treatment, ECT (but not isoflurane) patients showed declines in memory, fluency, and processing speed. At Follow-up, only autobiographical memory remained below Pretreatment level for ECT patients, but isoflurane patients had greater test-retest neurocognitive score improvement.

Conclusions

Our data reconfirm that isoflurane has an antidepressant effect approaching ECT with less adverse neurocognitive effects, and reinforce the need for a larger clinical trial.  相似文献   

9.
Electroconvulsive therapy (ECT) often results in a number of short- and long-time side effects including memory impairment for past and current events, which can last for several months after ECT treatment. It has been suggested that unilateral ECT (uECT) with electrodes placed over the non-dominant (typically right) hemisphere significantly reduces side effects, especially memory disturbances. It is important to note that cerebral dominance equates to speech dominance and avoiding this area of the brain also reduces speech dysfunction after ECT. Traditionally, the routine clinical determination of cerebral dominance has been through the assessment of hand, foot and eye dominance, which is an easy and inexpensive approach that, however, does not ensure accuracy. This review of literature on different methods and techniques for determination of cerebral dominance and provides evidence that functional transcranial Doppler sonography (fTCD) represents a valid and safe alternative to invasive techniques for identifying speech lateralisation. It can be concluded that fTCD, notwithstanding its costs, could be used as a standard procedure prior to uECT treatment to determine cerebral dominance, thereby further reducing cognitive side-effects of ECT and possibly making it more acceptable to both patients and clinicians.  相似文献   

10.
In nine schizophrenic patients (five males and four females) on haloperidol treatment, plasma and red blood cell (RBC) haloperidol neuroleptic activities were measured before and after ECT by radioreceptor assay. Five patients randomly selected from these patients also served as controls on another occasion and neuroleptic activities in plasma and RBC were examined before and after the premedication only. All patients given ECT showed a considerable increase in plasma and RBC haloperidol neuroleptic activities after ECT (% increase in plasma neuroleptic activity, 28–409%; mean + SD, 136 ± 155%, P<0.005, Wilcoxon test; % increase in RBC neuroleptic activity, 11–121%; mean + SD, 59 ± 40%, P<0.005). However, no significant increase was observed for either plasma or RBC haloperidol neuroleptic activity, when patients were examined after premedication only. It was suggested that ECT induced a transient redistribution of haloperidol. It remains to be studied whether this phenomenon is causally related to the previous observation that the combination therapy of ECT and neuroleptics is more effective in the treatment of schizophrenia than ECT alone.  相似文献   

11.
The pathogenic fungus Batrachochytrium dendrobatidis (Bd) has caused declines of many amphibian populations, yet the full course of the epizootic has rarely been observed in wild populations. We determined effects of elevation, habitat, and aquatic index (AI) on prevalence of infection among Panamanian amphibians sampled along 2 elevational transects. Amphibian populations on the Santa Fé transect (SFT) had declined in 2002, while those on the El Copé transect (ECT) were healthy until September 2004. In 2004 we sampled Bd along both transects, surveying the SFT 2 yr after decline, and surveying the ECT 4 mo prior to the arrival of Bd, during the epizootic, and 2 mo later. Overall prevalence of Bd along the ECT increased from 0.0 (95% CI 0.00-0.0003) to 0.51 (95% CI 0.48-0.55) over a 3 mo period, accompanied by significant decreases in amphibian abundance and species richness in all habitats. Prevalence of infection on the ECT was highest along riparian transects and at higher elevations, but not among levels of AI. Prevalence of infection on the SFT was highest in pool transects, and at higher elevations, but not among levels of AI. Riparian amphibian abundance and species richness also declined at SFT following detection of Bd in 2002. Variation among species, microenvironmental conditions, and the length of coexistence with Bd may contribute to observed differences in prevalence of Bd and in population response.  相似文献   

12.
Animal cells divide into two daughter cells by the formation of an actomyosin-based contractile ring through a process called cytokinesis. Although many of the structural elements of cytokinesis have been identified, little is known about the signaling pathways and molecular mechanisms underlying this process. Here we show that the human ECT2 is involved in the regulation of cytokinesis. ECT2 catalyzes guanine nucleotide exchange on the small GTPases, RhoA, Rac1, and Cdc42. ECT2 is phosphorylated during G2 and M phases, and phosphorylation is required for its exchange activity. Unlike other known guanine nucleotide exchange factors for Rho GTPases, ECT2 exhibits nuclear localization in interphase, spreads throughout the cytoplasm in prometaphase, and is condensed in the midbody during cytokinesis. Expression of an ECT2 derivative, containing the NH(2)-terminal domain required for the midbody localization but lacking the COOH-terminal catalytic domain, strongly inhibits cytokinesis. Moreover, microinjection of affinity-purified anti-ECT2 antibody into interphase cells also inhibits cytokinesis. These results suggest that ECT2 is an important link between the cell cycle machinery and Rho signaling pathways involved in the regulation of cell division.  相似文献   

13.
摘要 目的:探究瑞芬太尼联合丙泊酚对躁狂症患者电休克治疗后的再定向时间和认知功能的影响。方法:招募2018年2月至2019年9月在本院就诊的150例躁狂症患者,将患者分为对照组和观察组,各75例。通过简易精神状态检查(MMSE)评分系统比较电休克疗法(ECT)后的认知障碍。通过杨氏躁狂量表(YMRS)评分系统比较躁狂症患者的狂躁严重程度。通过MMSE评分系统比较躁狂症患者ECT后的时间定向能力。通过无创血压和心电图监测患者ECT前后的平均动脉压和心率。结果:两组患者一般资料统计无差异(P>0.05)。观察组术后5小时无障碍率较对照组升高(P<0.05),观察组术后5小时出现严重认知障碍率较对照组降低(P<0.05),中度认知障碍率两组比较无差异(P>0.05)。ECT后5小时和24小时观察组与对照组的YMRS评分比较无差异(P>0.05)。ECT前,观察组时间定向评分与对照组比较无差异(P>0.05),ECT后,观察组时间定向评分较对照组升高(P<0.05)。ECT前和ECT后,观察组的平均动脉压和心率比较无差异(P>0.05)。结论:在接受ECT的躁狂患者中,瑞芬太尼补充丙泊酚诱导麻醉不影响ECT的疗效,并且能减少ECT后认知障碍的发生,缩短重定向时间。  相似文献   

14.
PURPOSE: Electrochemotherapy (ECT) is an effective local therapy of human cutaneous cancers but has no effect on distant untreated tumors. We addressed whether tumor-associated antigens released after ECT could induce an efficient systemic immunity when associated with an appropriate immunoadjuvant. METHODS AND RESULTS: We first studied the nature of the cellular recruitment and the expression of various toll-like receptors (TLRs) in tumors treated by ECT. We found that ECT induced a massive recruitment of CD11c and CD11b positive cells in the tumors and a strong increase of TLR9 expression. We then tested antitumor effects of the combination: ECT followed by TLR-9 ligands, CpG oligodeoxynucleotides (CpG ODN), in three murine tumor models. We found that this combination triggered both potent local synergistic antitumor effects, on the ipsi-lateral ECT-treated tumor, and more interestingly, a systemic antitumor response on the contra-lateral untreated tumor, in the three models. The systemic protection was T-cell dependent as it was not observed in nude littermates. The combination induced tumor-specific T cell effectors in the tumor-draining lymph nodes and in the spleen which secreted significantly more gamma-interferon upon activation than with ECT or CpG ODN alone. CONCLUSIONS: Our data show that ECT and CpG ODN synergize and induce a significant increase of the local effect and a systemic T-dependent antitumor response. Such combination constitutes a potential innovative vaccination strategy using in situ tumor-associated antigens that could eventually be translated into the clinic.  相似文献   

15.
We present experimental measurements and theoretical predictions of ion transport in agar gels during reversible electroporation (ECT) for conditions typical to many clinical studies found in the literature, revealing the presence of pH fronts emerging from both electrodes. These results suggest that pH fronts are immediate and substantial. Since they might give rise to tissue necrosis, an unwanted condition in clinical applications of ECT as well as in irreversible electroporation (IRE) and in electrogenetherapy (EGT), it is important to quantify their extent and evolution. Here, a tracking technique is used to follow the space-time evolution of these pH fronts. It is found that they scale in time as , characteristic of a predominantly diffusive process. Comparing ECT pH fronts with those arising in electrotherapy (EChT), another treatment applying constant electric fields whose main goal is tissue necrosis, a striking result is observed: anodic acidification is larger in ECT than in EChT, suggesting that tissue necrosis could also be greater. Ways to minimize these adverse effects in ECT are suggested.  相似文献   

16.
Carthamus tinctorius L. (safflower) is one of the most commonly used Chinese herbal medicines to prevent and treat cardiac disease in clinical practice. However, the mechanisms responsible for such protective effects remain largely unknown. In this study, we investigated the anti-myocardial ischemia effects of a purified extract of C. tinctorius (ECT) both in vivo and in vitro. An animal model of myocardial ischemia injury was induced by left anterior descending coronary artery occlusion in adult rats. Pretreatment with ECT (100, 200, 400, 600 mg/kg body wt.) could protect the heart from ischemia injury by limiting infarct size and improving cardiac function. In the in vitro experiment, neonatal rat ventricular myocytes were incubated to test the direct cytoprotective effect of ECT against H2O2 exposure. Pretreatment with 100–400 μg/ml ECT prior to H2O2 exposure significantly increased cell viability as revealed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. ECT also markedly attenuated H2O2-induced cardiomyocyte apoptosis, as detected by Annexin V and PI double labeling with flow cytometry. The intracellular level of reactive oxygen species (ROS) was shown by 2′,7′-dichlorofluorescin diacetate (DCFH-DA), and ECT pretreatment significantly inhibited H2O2-induced ROS increase. We made a preliminary examination of the signaling cascade involved in ECT mediated anti-apoptotic effects. Phosphatidylinositol 3 kinase (PI3K) inhibitor (LY294002) blocked the cytoprotective effect conferred by ECT. Taken together, our findings provide the first evidence that the cardioprotective effects of ECT in myocardial ischemia operate partially through reducing oxidative stress induced damage and apoptosis. The protection is achieved by scavenging of ROS and mediating the PI3K signaling pathway.  相似文献   

17.
In anaphase, the spindle dictates the site of contractile ring assembly. Assembly and ingression of the contractile ring involves activation of myosin-II and actin polymerization, which are triggered by the GTPase RhoA. In many cells, the central spindle affects division plane positioning via unknown molecular mechanisms. Here, we dissect furrow formation in human cells and show that the RhoGEF ECT2 is required for cortical localization of RhoA and contractile ring assembly. ECT2 concentrates on the central spindle by binding to centralspindlin. Depletion of the centralspindlin component MKLP1 prevents central spindle localization of ECT2; however, RhoA, F-actin, and myosin still accumulate on the equatorial cell cortex. Depletion of the other centralspindlin component, CYK-4/MgcRacGAP, prevents cortical accumulation of RhoA, F-actin, and myosin. CYK-4 and ECT2 interact, and this interaction is cell cycle regulated via ECT2 phosphorylation. Thus, central spindle localization of ECT2 assists division plane positioning and the CYK-4 subunit of centralspindlin acts upstream of RhoA to promote furrow assembly.  相似文献   

18.
We have previously reported that plasma and red blood cell levels of haloperidol, a neuroleptic agent, significantly increased immediately after electroconvulsive shock therapy (ECT) in schizophrenic patients on long term haloperidol treatment. To elucidate the mechanism of this increase, we attempted to reproduce this phenomenon in female Wistar rats. After 4 successive days of ip administration of haloperidol (10 mg/kg body weight, once daily), rats were given ECT through corneal electrodes on the fifth day (a.c. 50 Herz, 55 mA, 2.0 sec). Haloperidol levels were determined in plasma and other major tissues using a radioreceptor assay for haloperidol distribution before and after ECT at appropriate time intervals. Plasma haloperidol level was significantly increased 1 min after ECT but tended to return to the control level (without ECT) after 5 min. A significant decrease in haloperidol concentration in tissues was not observed in any of the tissues examined including frontal cerebrum, striatum, and muscle tissues (gluteal muscles). However, the relatively high haloperidol level and the large volume of muscle tissues suggested that the muscle could be the source of the transient increase in haloperidol levels in plasma. This conclusion was also supported by the data showing no significant rise of plasma haloperidol level after ETC in rats previously given a muscle relaxant, succamethonium chloride.  相似文献   

19.
From a fundamental point of view, chemotherapy is the most widely used treatment for cancers despite its side effects on normal cells and tissues. Electrochemotherapy (ECT) is a method for increasing the permeability of cancer cells to drugs and, hence, decreasing their dosage. It apparently creates electropores on the cell membrane using electric pulses. ECT can decrease tumor volume; but this effect is not permanent, and partial regrowth has been reported. The aim of this study was to investigate the potential of magnetic fields in preventing the regrowth of tumors after ECT. Tumoral Balb/c mice were exposed to a magnetic field (15 mT, 50 Hz) for 12 days after treating additionally with 70 V/cm electric pulses and bleomycin at the first day. The magnetic field caused a significant reduction in tumor volumes, while there was no significant difference between the ECT and the electroporation with ECT and magnetic field groups. The exploited magnetic field (15 mT, 50 Hz) could decrease the tumor growth rate significantly, without any effect on ECT efficiency.  相似文献   

20.
应用自控、封闭、独立的生长室系统,研究了川西亚高山岷江冷杉根际土壤微生物数量对大气CO2浓度升高 (环境CO2浓度+350(±25)μmol·mol-1,EC)和温度升高(环境温度+2.2(±0.5)℃,ET)及其CO2浓度和温度同时升高 (ECT)的响应.结果表明,1)同对照(CK)相比,在6月、8月和10月,EC处理的根际细菌数量分别增加了35%、164%和312%,ET处理增加了30%、115%和209%,而EC和ET处理对根际放线菌和根际真菌数量影响不显著;ECT处理的根际放线菌数量分别增加了49%、50%和96%,根际真菌数量增加了151%、57%和48%,而ECT对根际细菌数量影响不显著.2)3种处理对非根际土壤微生物数量影响均不显著.3)在EC、ET和ECT处理下,微生物总数的根际效应明显,其R/S值分别为1.93、1.37和1.46(CK的R/S值为0.81).  相似文献   

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