961 resultados para Clinical pathway


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Polybrominated diphenyl ethers (PBDEs) are used extensively as flame-retardants and are ubiquitous in the environment and in wildlife and human tissue. Recent studies have shown that PBDEs induce neurotoxic effects in vivo and apoptosis in vitro. However, the signaling mechanisms responsible for these events are still unclear. In this study, we investigated the action of a commercial mixture of PBDEs (pentabrominated diphenyl ether, DE-71) on a human neuroblastoma cell line, SK-N-SH. A cell viability test showed a dose-dependent increase in lactate dehydrogenase leakage and 3-(4,5-dimethylthia-zol-2-yl)-2,5-diphenyl-tetrazolium bromide reduction. Cell apoptosis was observed through morphological examination, and DNA degradation in the cell cycle and cell apoptosis were demonstrated using flow cytometry and DNA laddering. The formation of reactive oxygen species was not observed, but DE-71 was found to significantly induce caspase-3, -8, and -9 activity, which suggests that apoptosis is not induced by oxidative stress but via a caspase-dependent pathway. We further investigated the intracellular calcium ([Ca2+](i)) levels using flow cytometry and observed an increase in the intracellular Ca2+ concentration with a time-dependent trend. We also found that the N-methyl d-aspartate (NMDA) receptor antagonist MK801 (3 mu M) significantly reduced DE-71-induced cell apoptosis. The results of a Western blotting test demonstrated that DE-71 treatment increases the level of Bax translocation to the mitochondria in a dose-dependent fashion and stimulates the release of cytochrome c (Cyt c) from the mitochondria into the cytoplasm. Overall, our results indicate that DE-71 induces the apoptosis of ([Ca2+](i)) in SK-N-SH cells via Bax insertion, Cyt c release in the mitochondria, and the caspase activation pathway.

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A new approach, short-oligonucleotide-ligation assay on DNA chip (SOLAC), is developed to detect mutations in rifampin-resistant Mycobacterium tuberculosis. The method needs only four common probes to detect 15 mutational variants of the rpoB gene within 12 h. Fifty-five rifampin-resistant M. tuberculosis isolates were analyzed, resulting in 87.3% accuracy and 83.6% concordance relative to DNA sequencing.

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Type I interferon (IFN) exerts its pleiotropic effects mainly through the JAK-STAT signaling pathway, which is presently best described in mammals. By subtractive suppression hybridization, two fish signaling factors, JAK1 and STAT1, had been identified in the IFN-induced crucian carp Carassius auratus L. blastulae embryonic (CAB) cells after treatment with UV-inactivated grass carp hemorrhagic virus (GCHV). Further, the full-length cDNA of STAT1, termed CaSTAT1, was obtained. It contains 2926 bp and encodes a protein of 718 aa. CaSTAT1 is most similar to rat STAT1 with 59% identity overall and displays all highly conserved domains that the STAT family possesses. Like human STAT1beta, it lacks the C-terminus acting as transcriptional activation domain in mammals. By contrast, only a single transcript was detected in virus-induced CAB cells. Expression analysis showed that CaSTAT1 could be activated by stimulation of CAB cells with poly I:C, active GCHV, UV-inactivated GCHV or CAB IFN, and displayed diverse expression patterns similar to that of mammalian STATI. Additionally, the expression of an antiviral gene CaMx1 was also induced under the same conditions, and expression difference between CaSTAT1 and CaMx1 was revealed by induction of CAB IFN. These results provide molecular evidence supporting the notion that the fish IFN signaling transduction pathway is similar to that in mammals. Fish IFN exerts its multiple functions, at least antiviral action, through a JAK-STAT pathway. (C) 2004 Elsevier Ltd. All rights reserved.

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This paper introduced a long-term ambulatory intragastric pH monitoring system, which is designed for prolonged ambulatory studies of Gastroesophageal Reflux Diseases. The whole system is composed of the gastric catheter with two pH sensors, a small data logger (Microdatalog), and a notebook PC. In this paper, the design of monitoring system hardware and software are described in detail. Clinical applications reveal good results.

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何首乌为常用中药,由何首乌及含何首乌的中成药制剂所引起的不良反应也时见报道,科学阐明不良反应的物质基础并提出解决方案对何首乌的使用十分重要。本论文研究了何首乌炮制前后KM小鼠肝脏毒性基因表达谱、生物活性及化学成分的变化。所获结果支持何首乌炮制的目的是减毒、改性(改变药效),何首乌生、熟异治的观点。制首乌对抑郁症的效果显著优于生首乌,这与本草所记载的何首乌炮制后补肝肾、益精血,归肝、肾经一致。 主要结果如下: 1、 生、制首乌的毒理基因芯片研究结果 何首乌的不良反应主要表现在肝损害方面。本研究建立了生何首乌和制何首乌不同剂量的肝毒性作用模型,体重指标统计发现生何首乌各剂量组平均体重显著下降,中剂量组(10 g/kg.d)体重下降20 %,高剂量组(20 g/kg.d)体重下降42%,50%动物死亡,提示动物机体能量代谢障碍;基因芯片研究结果表明何首乌是CYP450的抑制剂,生何首乌相对于制何首乌CYP3A4、CYP4A5显著下调,导致毒性成分在体内的吸收增加,服用大剂量的生何首乌后产生明显的肝毒性;主要对以下六条Pathway产生影响:①PPAR signaling pathway,主要毒性靶基因有RXRB CYP7a1、Acadl、Apoa2、Cyp4a、 FABP2 、MAPKKK5等基因。②Calcium signaling pathway,主要毒性靶基因有CAMK2B、CACNA1F、S100A1、 F2R、Ryr1、Slc8a2、Camk4 ③Neuroactive ligand-receptor interaction,主要毒性靶基因有Chrm4、 Ntsr2 、 GABRR1、 GRIK3、F2R等基因。④Wnt signaling pathway,主要毒性靶基因有Daam2、Rac1 等基因。⑤Complement and coagulation cascades,主要毒性靶基因有F2R、Serpina1b、Cfi 、FGA等基因。⑥Oxidative hosphorylation,主要毒性靶基因有Atp5e、NDUFA1等基因。生何首乌毒性明显强于制首乌,且生何首乌水煎液的毒性大于生何乌首丙酮提取物的毒性,这一结果表明,何首乌主要的毒性成分很可能并不仅仅是传统所认为的以大黄素为代表的蒽醌类化合物,而是何首乌中大量存在的有效组分二苯乙烯苷与大黄素相互作用的结果,这一研究结果与前述的何首乌对肝药酶的影响是一致的。后续生、制首乌的化学成分差异研究表明,炮制后二苯乙烯苷含量明显降低:生首乌为5.512 %、清蒸制首乌为3.811 %、豆制首乌为3.538 %,大黄素的含量炮制后显著升高,生首乌为0.094 %、清蒸制首乌为0.119 %、豆制首乌为0.126 %。 2 生、制首乌药效差异研究结果 本文采用慢性中等强度不可预知应激刺激模型(chronic unpredictable mild stress, CUMS)和动物行为绝望实验法,研究生、制首乌抗抑郁活性的差异,制首乌(5 g/kg.d)与模型组相比有显著差异(P< 0.01),生首乌制首乌(5g/kg.d)与模型组相比无显著差异,这一结果表明制首乌抗抑郁活性显著优于生首乌。 本文比较了生、制首乌对四氧嘧啶糖尿病模型小鼠血糖的影响的差异,生首乌(5 g/kg.d)与模型组相比有显著差异(P< 0.01),制首乌(5 g/kg.d)与模型组相比无显著差异,这一结果表明生首乌降糖活性优于制首乌。这一结果与历代中医古书中生首乌治疗消渴症(糖尿病)的记载一致。 3生、制首乌化学成分差异的研究结果 本文选用HPLC-DAD指纹图谱技术结合药效成分含量测定来研究生、制首乌化学成分的差异。炮制后,何首乌中的主要化学成分并未消失,只是其含量发生了改变。炮制后二苯乙烯苷含量明显降低:生首乌为5.512 %、清蒸制首乌为3.811 %、豆制首乌为3.538 %,大黄素的含量炮制后显著升高,生首乌为0.094 %、清蒸制首乌为0.119 %、豆制首乌为0.126 %。 综上所述,炮制前后何首乌中二苯乙烯苷和大黄素含量比的变化可能是何首乌炮制减毒、改性的物质基础。 根据上述结果我们建立了生、制首乌的质量控制新模式。 In recent years, some adverse drug reactions (ADR) about some traditional Chinese medicine were reported at times. As a Chinese medicine most in use, the ADRs of Radix Polygoni multiflori (RPM) and the medicines containing the RPM were also mentioned. The resolution of the problems caused by the ADRs is very important for the use of the RPM as a medicine. The process (or preparation) is a significant feature for the clinical use of the Chinese medicine and an important technology for the safe use and good effect of the Chinese medicine. By processing, the toxicity of the Chinese medicine can be reduced, its properties can be changed and curative effect can be enhanced at the same time. The changes of the gene expression profiles for KM mice hepatotoxic effects, and the change of the biological activity and the chemical composition after being processed of the RPm were studied in the present dissertation. The RPm heatotoxicity mechanism and the toxicity target genes were explained on the gene level for the first time. With the antidepressant activity, and the hypoglycemic effect as the target, the differences on the pharmacodynamics between the processed RPm and unprocessed RPm, for the first time, were investigated. The results obtained show that the antidepressant activity of the processed RPM is far higher than the ones of unprocessed RPm. As we know, the results were reported for the first time. The quality control systems (QCS) for the processed and the unprocessed RPm were founded. The HPLC-DAD was used in the systems founded on the basis of the toxicology and the pharmacodynamics experiments. As we know, the OCSs were reported for the first time. The above-mentioned experimental results confirm that the unique process theory of the traditional Chinese medicine (TCM) used for the process of the Radix Polygoni multiflori (RPm) is correct, i.e after being processed the toxicity of the RPm decreases and its Pharmacodynamic effects change. It is known to author that there have been no similar reports in the literatures up to now. The main experimental results are summarized as follows: 1 The results on the mice toxicology gene chip for the unprocessed and processed RPm The KM mice hepatotoxic model caused by the RPm at the different dosages was established in the present study. The results obtained show that the mouse average body weight obviously decreased in the groups at the different dosages of the unprocessed RPm: the 10 g/kg.d .group decreased 20%; 20 g/kg.d. group decreased 42%, and 50% mice died at 20 g/kg.d. group. The main experimental results on the mice toxicology gene chip The RPm is the CYP450 inhibitor. As compared with the processd RPm, the CYP3A4, CYP4A5 of the unprocessed RPm demonstrate the marked downregulation, which leads to the increase of the poison absorbtion into the body with the result that the unprocessed RPm yields the marked hepatotoxication. The hepatotoxication was produced because the following 6 pathways were affected: ①PPAR signaling pathway, the chief toxicity target genes are RXRB, CYP7a1, Acadl, Apoa2, Cyp4a, FABP2 and MAPKKK5 etc. ②Calcium signaling pathway, the chief toxicity target genes are CAMK2B, CACNA1F, S100A1, F2R, Ryr1,Slc8a2 and Camk4 etc. ③Neuroactive ligand-receptor interaction, the chief toxicity target genes are Chrm4, Ntsr2, GABRR1, GRIK3 and F2R etc. ④Wnt signaling pathway, the chief toxicity target genes are Daam2, Rac1 etc. ⑤Complement and coagulation cascades, the chief toxicity target genes are F2R, Serpina1b, Cfi and FGA etc. ⑥Oxidative phosphorylation, the chief toxicity target genes are Atp5e, NDUFA1 etc. The above experimental results, for the first time , demonstrate on the gene level that the unprocessed Rpm toxicity is far stronger than the processed RPm one, and the toxicity of the water decoction of the unprocessed RPm is greater than the one of its acetone extracts, which shows that the chief toxicity components of the RPm are probably not only the anthraquinones, for example, the emodin, but the complex compounds produced by the interaction between the emondin and the stilbene glucoside which is the largest component of the unprocessed RPm. The result is accordance with the above effect of the RPm on the hepatic drugenzyme. Aftter being processed, in fact, the content of the stibene glucoside in the RPm markedly decreases. 2. The results on the pharmacodynamic differences between the unprocessed and processed RPm The results obtained show that the effects of processing on RPm pharmacodynamic behaviour received in the Chinese Material Medica are correct. It is known to author that this is the first experimental result in the research materials now available. The chief results are as follows: For the treatment of the antidepressant, the curative effect of the processed RPm is far better than the one of the unprocessed RPm. By contrast with the above results, the hypoblycemic effect of the unprocessed RPm is better than the one of the processed RPm. 3. The results on the Chemical Composition The results obtained by using HPLC-DAD fingerprint and by the determination of effective component content show that the main chemical components in the RPm after being processed do not disappear, but their contents change. The contents of the stilbene glucoside (SG) and emodin in the different samples were determined as follows: SG contents 5.512 % for the unprocessed RPm 3.811 % for the processed RPm (Steamed) 3.588 % for the processed RPm (black soybean) Emodin contents 0.094 % for the unprocessed RPm 0.119 % for the processed RPm (Steamed) 0.126 % for the processed RPm (black soybean) The combination of above experimental results on the toxicity, the pharmacodynamics and the chemical composition indicates that the changes of the content ratio of SG/emodin may be the substance base of the toxicity decrease and pharmacodynamic changes of the RPM by the processing.

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目的:评价重离子束对皮肤恶性肿瘤放射治疗的近期疗效和毒副反应。方法:29例皮肤恶性肿瘤患者分6批接受重离子束放射治疗,其中恶性黑色素瘤13例,皮肤鳞癌及Bowen’s病各6例,基底细胞癌2例,其他皮肤恶性肿瘤2例。照射总剂量(50~70)GyE/(6~12)d,单次剂量5.5~11.67GyE,1f/d,连续治疗。采用RTOG标准和WHO近期疗效标准分别评价毒副反应和近期疗效。结果:截止2009-05,中位随访时间为13.5个月(1~25个月),随访率为100%。29例患者中完全缓解(CR)24例(82.8%),部分缓解(PR)5例(17.2%),有效率(RR)为100%,中位生存时间为22.8个月(95%CI:20.6~24.9)。皮肤反应0度11例(37.9%),Ⅰ度9例(31.0%),Ⅱ度6例(20.7%),Ⅲ度2例(6.9%),Ⅳ度1例(3.4%);血液毒副反应治疗前后无明显改变。结论:重离子束(12C6+)放射治疗皮肤恶性肿瘤近期疗效好,并发症轻,远期疗效、晚期副反应等尚需进一步长期全面的观察和更多的研究提供依据。

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p14ARF是新近发现的一种具有细胞周期调节功能的抑癌基因,P14ARF主要定位于核仁,但也有少部分位于核质。p14ARF在部分人类肿瘤中频发失活,其表达异常导致肿瘤的发生机制及以P14ARF为靶点进行的肿瘤治疗越来越受到重视。现对于Pl4ARF相关信号通路的研究进展进行了综述。

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As a recently developed and powerful classification tool, probabilistic neural network was used to distinguish cancer patients from healthy persons according to the levels of nucleosides in human urine. Two datasets (containing 32 and 50 patterns, respectively) were investigated and the total consistency rate obtained was 100% for dataset 1 and 94% for dataset 2. To evaluate the performance of probabilistic neural network, linear discriminant analysis and learning vector quantization network, were also applied to the classification problem. The results showed that the predictive ability of the probabilistic neural network is stronger than the others in this study. Moreover, the recognition rate for dataset 2 can achieve to 100% if combining, these three methods together, which indicated the promising potential of clinical diagnosis by combining different methods. (C) 2002 Elsevier Science B.V. All rights reserved.