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1.
2.
《Bioorganic & medicinal chemistry》2020,28(22):115739
N-phenyl ureidobenzenesulfonates (PUB-SOs) is a new class of promising anticancer agents inducing replication stresses and cell cycle arrest in S-phase. However, the pharmacological target of PUB-SOs was still unidentified. Consequently, the objective of the present study was to identify and confirm the pharmacological target of the prototypical PUB-SO named 2-ethylphenyl 4-(3-ethylureido)benzenesulfonate (SFOM-0046) leading to the cell cycle arrest in S-phase. The antiproliferative and the cytotoxic activities of SFOM-0046 were characterized using the NCI-60 screening program and its fingerprint was analyzed by COMPARE algorithm. Then, human dihydroorotate dehydrogenase (hDHODH) colorimetric assay, uridine rescuing cell proliferation and molecular docking in the brequinar-binding site were performed. As a result, SFOM-0046 exhibited a mean antiproliferative activity of 3.5 μM in the NCI-60 screening program and evidenced that leukemia and colon cancer cell panels were more sensitive to SFOM-0046. COMPARE algorithm showed that the SFOM-0046 cytotoxic profile is equivalent to the ones of brequinar and dichloroallyl lawsone, two inhibitors of hDHODH. SFOM-0046 inhibited the hDHODH in the low nanomolar range (IC50 = 72 nM) and uridine rescued the cell proliferation of HT-29, HT-1080, M21 and MCF-7 cancer cell lines in the presence of SFOM-0046. Finally, molecular docking showed a binding pose of SFOM-0046 interacting with Met43 and Phe62 present in the brequinar-binding site. In conclusion, PUB-SOs and notably SFOM-0046 are new small molecules hDHODH inhibitors triggering replication stresses and S-phase arrest. 相似文献
3.
Andreas König 《European Journal of Wildlife Research》2008,54(1):101-109
Throughout Central Europe, foxes have taken over urban areas as their habitat. In Southern Germany, these foxes are also carriers
of the small fox tapeworm, which causes a serious zoonotic infection in humans. Therefore, a survey was carried out in a suburb
of the city of Munich. A postal questionnaire was used to analyse the attitudes, opinions and fears of these participants
towards their urban foxes and the background to these attitudes. Questionnaires were sent to all households with gardens and
collected in again via the community council. Seven hundred and seventy-nine or 31% of questionnaires were returned. Only
a few people are afraid of the fox itself; however, 55% are afraid of the fox tapeworm. Worming the animals is the preferred
counter-measure, with 81% in favour. The majority of inhabitants are pleased to see a fox in the community and feel the animals
have a right to live. People are afraid of the tapeworm either because they have children in the household or because of increased
knowledge of the subject or because it has increasingly become an issue. On the basis of the results of this study, it is
to be expected that radical solutions such as killing the foxes are unlikely to be accepted among the population. Worming
of the foxes does, however, meet with general approval. 相似文献
4.
A.C. Gonçalves T.D. Matos H.R. Simões-Teixeira M. Pimenta Machado M. Simão Ó.P. Dias M. Andrea G. Fialho H. Caria 《Gene》2014
Low-frequency sensorineural hearing loss (LFSNHL) is an unusual type of HL in which frequencies at 2000 Hz and below are predominantly affected. Most of the families with LFSNHL carry missense mutations in WFS1 gene, coding for wolframin. 相似文献
5.
Aaron B. Bernstein Elisabeth Preisig Hubert E. Schroeder 《Cell and tissue research》1990,259(3):603-606
Summary A diseased and mechanically treated surface of root cementum is known, clinically, to favor periodontal regeneration. The present investigation was undertaken to test whether previously diseased and experimentally treated root surfaces can support the in-vitro formation of a new collagenous matrix. Three teeth extracted for advanced periodontitis were treated first with 5% sodium hypochlorite for 2 h to remove all organic material from the root surface. After the healthy, apical one third of the root was cut off, the roots were scaled with moderate pressure to remove visible calculus. Non-demineralized root discs were cut and placed on a co-culture of periodontal ligament- and alveolar bone-derived cells. After 7 weeks in culture, either one of two matrix types was found along the root surface. The most frequent matrix consisted of clusters of cells layered within densely aggregated collagen fibrils. The other, less frequent matrix consisted of loosely arranged collagen fibrils adjacent to the cemental surface. The findings support the notion that, in vitro, a collagenous matrix is formed in contact to diseased and experimentally treated root surfaces. However, the smooth, non-demineralized and scaled cemental surface does not appear to be a suitable substrate for interdigitation with newly produced collagen fibrils. 相似文献
6.
Digital images of ex situ germplasm stored in the Sardinian Germplasm Bank (BG-SAR) were used for the application of image analysis techniques at the Stazione Sperimentale di Granicoltura per la Sicilia. The analysed accessions refer to 148 taxonomic units belonging to 102 genera and 47 families, typical of the Sardinian flora, and of the Mediterranean basin in general.The images of diaspores were acquired by a flatbed scanner and elaborated with a macro specially developed for the morphometric and colorimetric measurements. This method allowed carrying out a database for the characterization of autochthonous germplasm in entry to the bank and the realization of statistic classifiers for the discrimination of genera and species within the following families: Apiaceae, Boraginaceae, Caryophyllaceae, Cistaceae, Fabaceae and Scrophulariaceae. Such classifiers, based on the linear discriminant analysis (LDA) technique and checked by cross-validation, showed a performance included between 74.3% and 96.4%.In addition, for the genus Astragalus, it was possible to elaborate a classifier able to identify very similar taxa of a species complex, obtaining a performance between 83.7% and 100%. Such analysis proved the validity of the methodology also from the taxonomic point of view.Suggestions for subsequent methodological progress, which could offer applications in other research issues, such as ecological analysis, soil seed bank and archaeological botany are proposed. 相似文献
7.
目的:探讨腹腔镜粘连松解术治疗粘连性肠梗阻(AIO)的疗效,减少再梗阻率。方法:将120 例AIO 患者随机分为两组,每
组60 例,开腹组实施开腹手术,腹腔镜组实施腹腔镜粘连松解术,观察两组术后恢复及并发症发生情况,对再梗阻危险因素进行
Logistic 回归分析。结果:腹腔镜组术中失血量(73.48± 9.32)mL,少于开腹组的(207.45± 33.21)mL(P<0.05);腹腔镜组手术、术后
镇痛、下床活动、肠恢复蠕动、肛门恢复排气、拔除尿管及住院时间分别为(69.15± 10.13)min、(14.67± 7.23)h、(27.14± 7.04)h、
(3.11± 0.96)d、(3.24± 1.02)d、(3.37± 1.23)d、(7.95± 3.05)d,均短于开腹组的(83.84± 9.24)min、(27.38± 8.02)h、(36.23± 5.87)
h、(4.05± 1.35)d、(4.35± 1.74)d、(5.02± 2.13)d、(10.35± 3.71)d(P<0.05);腹腔镜组并发症发生率、再梗阻率分别为10.00%、
10.00%,均低于开腹组的33.33%、40.00%(P<0.05);多因素Logistic 回归分析显示开腹手术、手术时间≥ 60 min 是再梗阻发生的独
立危险因素。结论:腹腔镜手术治疗AIO 疗效优于开腹手术,而且并发症与再梗阻率低。 相似文献
8.
《Cytokine》2015,73(2):224-225
Balanced regulation of cytokine secretion in T cells is critical for maintenance of immune homeostasis and prevention of autoimmunity. The Rho-associated kinase (ROCK) 2 signaling pathway was previously shown to be involved in controlling of cellular movement and shape. However, recent work from our group and others has demonstrated a new and important role of ROCK2 in regulating cytokine secretion in T cells. We found that ROCK2 promotes pro-inflammatory cytokines such as IL-17 and IL-21, whereas IL-2 and IL-10 secretion are negatively regulated by ROCK2 under Th17-skewing activation. Also, in disease, but not in steady state conditions, ROCK2 contributes to regulation of IFN-γ secretion in T cells from rheumatoid arthritis patients. Thus, ROCK2 signaling is a key pathway in modulation of T-cell mediated immune responses underscoring the therapeutic potential of targeted inhibition of ROCK2 in autoimmunity. 相似文献
9.
10.
《DNA Repair》2017
Human PrimPol is a recently discovered bifunctional enzyme that displays DNA template-directed primase and polymerase activities. PrimPol has been implicated in nuclear and mitochondrial DNA replication fork progression and restart as well as DNA lesion bypass. Published evidence suggests that PrimPol is a Mn2+-dependent enzyme as it shows significantly improved primase and polymerase activities when binding Mn2+, rather than Mg2+, as a divalent metal ion cofactor. Consistently, our fluorescence anisotropy assays determined that PrimPol binds to a primer/template DNA substrate with affinities of 29 and 979 nM in the presence of Mn2+ and Mg2+, respectively. Our pre-steady-state kinetic analysis revealed that PrimPol incorporates correct dNTPs with 100-fold higher efficiency with Mn2+ than with Mg2+. Notably, the substitution fidelity of PrimPol in the presence of Mn2+ was determined to be in the range of 3.4 × 10−2 to 3.8 × 10−1, indicating that PrimPol is an error-prone polymerase. Furthermore, we kinetically determined the sugar selectivity of PrimPol to be 57–1800 with Mn2+ and 150–4500 with Mg2+, and found that PrimPol was able to incorporate the triphosphates of two anticancer drugs (cytarabine and gemcitabine), but not two antiviral drugs (emtricitabine and lamivudine). 相似文献