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1.
As epithelioid trophoblastic tumor (ETT) shares similar clinical features with other gestational trophoblastic neoplasms (GTNs), it is likely to be clinically misdiagnosed and subsequently treated in an improper way. This study aimed to identify the sonographic features of ETT that are distinct from other GTNs, including placental site trophoblastic tumor (PSTT) and invasive mole/choriocarcinoma (IM/CC). Here, we retrospectively analyzed ultrasound images of 12 patients with ETT in comparison with those of 21 patients with PSTT and 24 patients with IM/CC. The results showed that maximal diameter and hemodynamic parameters were not significantly different among ETT, PSTT and IM/CC (P>0.05). However, a well-circumscribed border with hypoechogenic halo was identified in the gray-scale sonogram in all 12 cases of ETT, while only in 1 out of 21 cases of PSTT and 1 out of 16 cases of IM/CC (P<0.001 for ETT vs. PSTT or IM/CC). Moreover, a peripheral pattern of Doppler signals was observed in 11 out of 12 ETT lesions, showing relatively more Doppler signal spots around the tumor border than within the boundary, while a non-peripheral pattern of Doppler signals in all 21 PSTT cases and 14 out of 16 IM/CC cases: with minimal, moderate or remarkable signal spots within the tumor, but not along the tumor (P<0.001 for ETT vs. PSTT or IM/CC). These distinct sonographic features of ETT correlated with histopathologic observations, such as expansive growth pattern and vascular morphology. Thus, we draw the conclusions that the well-circumscribed border with peripheral Doppler signal may serve as a reliable sonographic feature to discriminate ETT from other types of GTNs. With further validation in a larger patient set in our ongoing multi-center study, this finding will be potentially developed into a non-invasive pre-operative GTN subtyping method for ETT.  相似文献   

2.
The binding of actinomycin D (actD) to fixed human metaphase chromosomes was studied by using autoradiography with [3H]actD and indirect immunofluorescence with a specific anti-actD antibody. At concentrations of 0.01 and 0.1 micrograms/ml there was a uniform distribution of drug along the chromosomes as observed by both methods. This is the first study to date characterizing actD binding at such low concentrations to human chromosomes. Since actD intercalates into the DNA helix with GC specificity, our observations indicate that detectable differences in base composition along the lengths of human chromosomes are minimal.  相似文献   

3.
At high concentrations (10 mug/ml), actinomycin D inhibited deoxyribonucleic acid (DNA) synthesis in Bacillus subtilis. Inhibition occurred quickly (in less than 1 min) and was complete. In strain 23 thy his, inhibition of DNA synthesis by actinomycin D was followed by partial degradation of one of the two daughter strands to acid-soluble products. Degradation began at the replication point and proceeded over a distance equal to about 12% of a chromosome in length. Actinomycin D played some essential part in degradation, since exposure of the cells to other treatments or agents which inhibit growth did not lead to the above result.  相似文献   

4.
Refractility as indicated by light microscopy, electron microscopy of thin sections, and freeze fracture etching was increased and maintained in a cortexless mutant, A(-)1, of Bacillus cereus var. alesti by the addition during sporulation stage 4 of actinomycin D, which prevents the terminal lysis of spore core associated with sporulation in this organism. (45)Calcium uptake levels and dipicolinic acid (DPA) content were similarly maintained. The location of these components appears to be in the spore protoplast. In the parent A(-), treated with actinomycin D during stage 4, spore particles with similar morphology to the mutant, that is without a cortex and with the characteristics of refractility, were obtained. A major difference in sensitivity to actinomycin D between the processes of (45)Ca uptake and DPA synthesis was observed. Some heat resistance in A(-) made cortexless by actinomycin D could be observed. These studies indicate that the role of the cortex is not to produce the dehydrated refractile spore state but to maintain it.  相似文献   

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Summary The incidence of ring shaped nucleoli was studied by means of light and electron microscopical methods in liver cells of rats injected intravenously with Actinomycin D in a dose of 150 g per kg body weight.Ring shaped nucleoli were most frequent 20 minutes after administration of Actinomycin D. The number of fragmented nucleoli was increased 20 minutes after administration of the drug and did not decrease even after 72 hours.Fibrillar ring like inclusions within nuclei and more perichromatin granules at the periphery of nucleoli were observed after treatment with Actinomycin D.
Zusammenfassung Die Wirkung von Aktinomycin D (150 g/kg) auf die Leberzellen der Ratte wurde licht- und elektronenenmikroskopisch untersucht. 20 min nach intravenöser Aktinomycin-D-Gabe wurden ringörmige Nukleolen beobachtet. Die Zahl der fragmentierten Nukleolen war 20 min nach der Applikation gesteigert. Ihre relative Zahl änderte sich nach Aktinomycingabe nicht. Nach Behandlung der Tiere mit Aktinomycin D kann man in den Kernen der Leberzellen fibrilläre ringförmige Einschlüsse und eine größere Menge von perichromatin-granules an der Peripherie der Nukleolen beobachten.


The authors are indebted to M. Mikoláová, V. Povolná, I. erníková and Dr. M. Titlbach for their help, to Dr. J. Chaloupka for providing Actinomycin D and to Professor Busch and Professor Wolf for many helpful suggestions.  相似文献   

7.
Savintsev  I. V.  Vekshin  N. L. 《Molecular Biology》2002,36(4):575-580
The mechanism of actinomycin D (AMD) and 7-aminoactinomycin D (7AAMD) interaction with DNA and model nucleotide compounds was studied by absorption and fluorescence spectroscopy (steady-state, phase-modulation, and polarization). It was shown that complex formation does not result in energy transfer from photoexcited nucleotides to the phenoxazone chromophore of 7AAMD, which indicates the absence of stacking-like intercalation. This fact is fundamentally important to explain the biological effect of actinomycin on cells. A basic difference was revealed in the complex-forming properties of AMD and 7AAMD. Thus AMD is capable of binding to guanine micelles to destroy them; 7AAMD forms no complexes with either guanine micelles or polyguanylic acid. 7AAMD binding sites on DNA can differ substantially from AMD binding sites. However, strong competition is observed between AMD and 7AAMD for the binding site in oligonucleotide HP1 used as a DNA hairpin model. The effective diameters of 7AAMD–HP1 complex and free 7AAMD were determined using the Levshin–Perren equation.  相似文献   

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摘要 目的:探究早期异位妊娠患者经阴道彩色多普勒示可疑妊娠滋养细胞流动与血清甲胎蛋白水平的相关性。方法:选择2021年1月至12月在本院收治的100例早期异位妊娠患者为观察研究对象。并选择同时期在本院例行正常产检的100例宫内妊娠孕妇为对照组。所有受试者进行阴道超声检查和彩色多普勒检查,并抽血进行甲胎蛋白的定量测定。测定子宫动脉、滋养细胞血流阻力及血清甲胎蛋白含量。结果:观察组腹痛、阴道不规则出血发生率较对照组升高(P<0.05)。观察组收缩期峰值速速、舒张末期速度较对照组升高,观察组滋养细胞血流阻力指数RI较对照组降低(P<0.05)。观察组收缩期峰值速速、舒张末期速度较对照组升高,观察组子宫动脉血流阻力指数RI较对照组降低(P<0.05)。观察组血清甲胎蛋白含量较对照组升高(P<0.05)。异位妊娠患者血清甲胎蛋白与滋养细胞血流RI呈负相关(r=-0.425,P<0.001)。结论:早期异位妊娠患者血清甲胎蛋白升高,经阴道彩色多普勒检查显示滋养细胞存在高流量-低阻力血管,滋养细胞血流阻力RI与血清甲胎蛋白呈负相关。  相似文献   

10.
After starvation for deoxyribosides, the deoxyribonucleic acid (DNA) of Lactobacillus acidophilus is restricted to a localized region of the cell. (3)H-uracil is first incorporated into such a restricted region but subsequently is found throughout the cell. This spread occurs despite the absence of protein synthesis and a major reduction in the rate of ribonucleic acid (RNA) synthesis. However, blocking RNA synthesis with actinomycin D restricts incorporation to a localized region of the cell. It is concluded that uracil is first incorporated into RNA in the bacterial nucleus from which it subsequently spreads through the cell. Actinomycin D could prevent this spread by preventing the completion of RNA molecules, which therefore do not dissociate from the DNA template.  相似文献   

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Y C Chiao  T R Krugh 《Biochemistry》1977,16(4):747-755
Mn(II) ions have been used as a paramagnetic probe to investigate the geometry of drug-oligonucleotide complexes. Nuclear magnetic resonance and electron spin resonance experiments show that Mn(II) ions bind approximately two orders of magnitude stronger to the 5'-terminal phosphate group than to the 3'-5' phosphodiester linkage of deoxydinucleotides. By using mixtures of nucleotides in which only one nucleotide contains a terminal phosphate group, the location of the Mn(II) ion in the drug-nucleotide-Mn(II) complexes may be preselected. The paramagnetic induced relaxation of the nuclear spin systems in these complexes has been used to investigate the geometry of these complexes. These data confirm that actinomycin D is able to recognize and preferentially bind guanine (as opposed to adenine) nucleotides in the quinoid portion of the phenoxazone ring, while both adenine and guanine will bind to the benzenoid portion of the phenoxazone ring. These results suggest that stacking forces are primarily responsible for the general requirement of a guanine base when actinomycin D binds to DNA.  相似文献   

14.
A molecular model for the inversion of the CD spectra of actinomycin D in the presence of gem-diols is proposed, in terms of the inversion of chirality of the peptide groups directly connected to the phenoxazone ring.  相似文献   

15.
The treatment of termite male spermatogonia with actinomycin D induces highly elongated and finely banded late prophase and prometaphase chromosomes as evidenced by the silver staining method. Actinomycin D suppresses the silver staining of nucleolar organizing regions in prometaphase and reduces it in metaphase chromosomes.  相似文献   

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摘要 目的:探讨甲基转移酶样蛋白3(METTL3)在5-氟尿嘧啶耐药中的作用机制。方法:大剂量间歇诱导法建立5-FU耐药细胞株。在耐药组细胞中分别敲减METTL3及EZH2抑制GSK343处理。qPCR及Western blot检测METTL3和EZH2表达。CCK-8检测各组细胞增殖情况。m6A甲基化RNA免疫沉淀技术分析EZH2 mRNA m6A修饰修饰情况。结果:各药物浓度处理下的耐药组细胞增殖活性与未处理细胞无显著差异(P>0.05)而原代细胞组肠癌细胞较未处理细胞在0.5-10 μg/mL处理下细胞增殖活性显著减低(P<0.01)。耐药组细胞与原代细胞组相比,METTL3及EZH2表达水平显著升高(P<0.01)。耐药组细胞METTL3敲减后或GSK343处理后,在0.5 μg/mL-10 μg/mL浓度间下的细胞增殖活性与0 μg/mL处理细胞增殖活性相比显著减低(P<0.05)。耐药组细胞METTL3敲减细胞的EZH2表达与对照细胞比,显著下调(P<0.01)。m6A甲基化RNA免疫沉淀实验显示耐药组细胞METTL3敲减细胞的EZH2 mRNA m6A修饰水平(m6A富集度为6361.95±67.47%),较未敲减细胞修饰水平(396.30±57.74)显著减低(P<0.01)。结论:METTL3在肠癌细胞5-FU耐药抵抗中起到关键作用,靶向抑制METTL3有望成为缓解肠癌耐药的重要分子靶点。  相似文献   

18.
A simple, sensitive, and inexpensive method is presented for measuring the binding of actinomycin D (AMD) to either chromatin or DNA. The procedure gives results which are comparable with those obtained by the optical titration procedure, but is superior to that method in that it does not require continuous attention, can be used with turbid chromatin preparations, and allows simultaneous processing of several samples. Chromatin or DNA that has been allowed to react with AMD is subjected to sucrose density gradient centrifugation to remove unbound antibiotic. The AMD-DNA or AMD-chromatin complex is then dissociated by incubation with 5m urea, and the released AMD is extracted with ether and estimated spectrophotometrically.  相似文献   

19.
Protein kinase D (PKD), also called protein kinase C (PKC)mu, is a serine-threonine kinase that is involved in diverse areas of cellular function such as lymphocyte signaling, oxidative stress, and protein secretion. After identifying a putative PKD phosphorylation site in the Toll/IL-1R domain of TLR5, we explored the role of this kinase in the interaction between human TLR5 and enteroaggregative Escherichia coli flagellin in human epithelial cell lines. We report several lines of evidence that implicate PKD in TLR5 signaling. First, PKD phosphorylated the TLR5-derived target peptide in vitro, and phosphorylation of the putative target serine 805 in HEK 293T cell-derived TLR5 was identified by mass spectrometry. Furthermore, mutation of serine 805 to alanine abrogated responses of transfected HEK 293T cells to flagellin. Second, TLR5 interacted with PKD in coimmunoprecipitation experiments, and this association was rapidly enhanced by flagellin treatment. Third, pharmacologic inhibition of PKC or PKD with G?6976 resulted in reduced expression and secretion of IL-8 and prevented the flagellin-induced activation of p38 MAPK, but treatment with the PKC inhibitor G?6983 had no significant effects on these phenotypes. Finally, involvement of PKD in the p38-mediated IL-8 response to flagellin was confirmed by small hairpin RNA-mediated gene silencing. Together, these results suggest that phosphorylation of TLR5 by PKD may be one of the proximal elements in the cellular response to flagellin, and that this event contributes to p38 MAPK activation and production of inflammatory cytokines in epithelial cells.  相似文献   

20.
《Endocrine practice》2019,25(11):1158-1165
Objective: Macrosomia is closely associated with gestational diabetes mellitus (GDM) but its relationship with maternal intermediate state gestational blood glucose (ISGBG; normal fasting blood glucose and 7.8 mmol/L <1 hour blood glucose &lsqb;BG] <10 mmol/L or 6.7 mmol/L <2 hour BG <8.5 mmol/L) is unclear. Here, we analyzed the clinical characteristics and pregnancy outcomes and explored risk factors for macrosomia in women with ISGBG.Methods: A total of 847 women with normal glucose tolerance gestation, 330 with ISGBG, and 99 with GDM were included. Maternal and fetal clinical data were collected and 3-point BG following oral glucose tolerance test, fasting insulin, glycated hemoglobin, and blood lipids profile were measured.Results: The incidence rate of macrosomia among the neonates of women with ISGBG was as high as 10.9%. In the ISGBG group, prepregnancy body mass index (BMI), gestational weight gain (GWG) and the proportion of women with excessive GWG (eGWG) were significantly higher in women with macrosomia compared with those who delivered a normal weight neonate. In women with ISGBG, neonate weight was positively correlated with maternal prepregnancy weight (r = 0.183, P<.01), prepregnancy BMI (r = 0.135, P<.01), and GWG (r = 0.255, P<.01), and negatively correlated with high-density lipoprotein cholesterol (r = -0.172, P<.01). Nonetheless, only eGWG was an independent risk factor (odds ratio = 3.18, 95% confidence interval = 1.26 to 7.88, P<.05) for macrosomia. The risk of macrosomia in pregnant women with prepregnancy BMI <25 kg/m2 or BMI ≥25 kg/m2 and eGWG was 3.39 and 3.27 times, respectively.Conclusion: The incidence rate of macrosomia is increased in women with ISGBG and eGWG is the strongest independent risk factor. In order to reduce the risk for macrosomia, timely lifestyle intervention to promote appropriate weight gain during pregnancy deserves evaluation.Abbreviations: AUC = area under the curve; BG = blood glucose; 1 hour BG = 1 hour blood glucose after OGTT; 2 hour BG = 2 hour blood glucose after OGTT; BMI = body mass index; CI = confidence interval; eGWG = excessive gestational weight gain; FBG = fasting blood glucose; FINS = fasting insulin; GDM = gestational diabetes mellitus; HbA1c = glycated hemoglobin; HDL-C = high-density lipoprotein cholesterol; HOMA-IR = homeostasis model assessment of insulin resistance index; ISGBG = intermediate state gestation blood glucose; LDL-C = low-density lipoprotein cholesterol; Ln = natural logarithm; MLBW = mature low birth weight; NGTG = normal glucose tolerance gestation; OGTT = oral glucose tolerance test; OR = odds ratio; SD = standard deviation  相似文献   

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