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71.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.  相似文献   
72.
Extensive research has indicated that miRNAs are crucial for the occurrence and progression of cancers. miR-451a, involved in breast cancer (BC), is one of the miRNAs. This study focused on the mechanism by which miR-451a regulates BC. The levels of miR-451a in BC tissues and cell lines were examined using quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan‒Meier analysis showed that this was intimately related to the patient's overall survival rate. Functional experiments revealed the negative effects of miR-451a on the abilities of BC cells to multiply (tested by Cell Counting Kit-8), migrate (tested by wound healing assay), and invade (tested by Transwell assay) and its positive effects on apoptosis (tested by flow cytometry). Western blotting indicated that the expression of tumor-related proteins was affected by miR-451a. Moreover, in vivo experiments suggested that tumor growth was clearly restrained by an miR-451a agonist in a xenograft tumor model. Bioinformatic analysis indicated that miR-451a directly targeted Cyclin D2 (CCND2), as demonstrated by the luciferase reporter assay. An opposite change in the level of CCND2 and miR-451a in BC was indicated by qRT-PCR, western blotting, and immunohistochemistry. Subsequently, functional experiments and western blotting analysis confirmed that CCND2 accelerated BC progression, which was regulated by miR-451a. Cumulatively, research on miR-451a may be valuable for BC treatment.  相似文献   
73.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
74.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.  相似文献   
75.
Several inflammatory markers have been investigated as prognostic parameters in a variety of cancer population with mostly favorable results. This study aimed to verify the significance of common inflammatory markers as prognostic variables and assess whether a selective combination of them as prognostic inflammation score (PIS) could further improve their prognostic values in surgical patients with colorectal cancer (CRC). A total of 265 patients who had undergone curative resection of CRC were reviewed retrospectively. Preoperative levels of inflammatory markers such as serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell count (WBC), and neutrophil/lymphocyte ratio (NLR) were assessed by uni- and multivariate survival analysis with disease-free (DFS) and disease-specific survival (DSS). PIS was constructed with a selective combination of inflammatory markers which were independently significant. On univariate analysis, CRP, ESR, and NLR were significantly associated with DFS and DSS. On multivariate analysis, CRP and NLR were independently significant prognostic variables for DSS and DFS respectively (P=0.013, P=0.021). When PIS was constructed with combination of CRP and NLR, it was independently and significantly associated with both DFS and DSS (P=0.006, P=0.010). Furthermore, PIS was superior to CRP for DSS (HR=15.679 vs. HR=5.183), and NLR for DFS in terms of prognosticating power (HR=4.894 vs. HR=2.687). When PIS is constructed with combination of CRP and NLR, it is a potentially significant prognostic variable associated with poor survival regardless pathologic prognostic variables in patients with CRC after curative resection.  相似文献   
76.
Colorectal cancer (CRC) is one of the most common malignancy cancers in the world. Aberrant microRNA expression is involved in human diseases including cancer. In the present study, we investigated the miR-892a's role in CRC cell proliferation. We found that miR-892a was frequently upregulated in human colorectal cancer tissues and cell lines compared with the matched tumor adjacent tissues and normal colonic cell line FHC. Overexpression of miR-892a promoted cell proliferation and colony formation of CRC. Bioinformatics analysis further revealed PPP2R2A was identified as a potential miR-892a. Overexpression of miR-892a-in SW480 cells reduced PPP2R2A protein expression. Subsequently, data from luciferase reporter assays showed that PPP2R2A 3′-untranslated region (3′-UTR) carried the directly binding site of miR-892a. Furthermore, siRNA-mediated silencing of PPP2R2A blocked the inhibitory effect of miR-892a-in on CRC cell growth. In sum, our data provided compelling evidence that overexpression of miR-892a may provide a selective growth promotion for CRC cells by direct suppression of PPP2R2A expression.  相似文献   
77.
目的探讨水通道蛋白(AQP)5基因对异位子宫内膜腺上皮细胞增殖及迁移的影响。方法构建可靶向沉默AQP5基因的质粒, 在293T细胞中包装形成病毒颗粒后, 感染原代培养的异位子宫内膜腺上皮细胞, 分别通过逆转录PCR及蛋白质印迹法鉴定异位子宫内膜腺上皮细胞中AQP5 mRNA和蛋白表达。MTT法测定细胞增殖; Transwell技术检测细胞的体外迁移能力; 蛋白质印迹法检测丝氨酸/苏氨酸蛋白酶(AKT)活化情况。构建裸鼠腹腔内子宫内膜异位症体内模型, 考察阴性对照组和AQP5沉默组子宫内膜腺上皮细胞在裸鼠腹腔内瘤体生长情况及腹膜转移情况。结果体外实验结果显示, AQP5沉默后异位子宫内膜腺上皮细胞的增殖能力在第7天时明显抑制( P < 0.05);AQP5沉默组异位子宫内膜腺上皮细胞磷酸化(p-AKT)表达减少, 而AKT表达无改变, p-AKT/AKT减少( P < 0.05);AQP5沉默组比阴性对照组迁移细胞数减少( P < 0.05)。体内实验结果显示, 与阴性对照组比较, AQP5沉默组瘤体结节数相对较少, 体积较小, 其中腹膜瘤体结节数少于阴性对照组( P < 0.05)。 结论AQP5基因沉默可抑制异位子宫内膜腺上皮细胞的增殖及迁移能力, 其机制可能与AKT活化有关。  相似文献   
78.
《Human immunology》2015,76(7):480-487
Previous animal studies showed that donor-derived blood cells treated with mitomycin C (MMC) prolong allograft survival when injected into recipients. This model was effective with whole blood, peripheral blood mononuclear cells (PBMC) (monocytes being the active cell subpopulation) or dendritic cells. In view of a potential clinical application, we study now the immunosuppressive properties of human myeloid cells in vitro. Mature dendritic cells (generated from naïve monocytes) or monocytes treated with mitomycin C do not or only weakly inhibit allogeneic T cells in vitro, whereas cells in an early differentiation state between monocytes and DC exert suppressive activity when treated with MMC. In contrast, DC generated from MMC-treated monocytes show the morphology and phenotype of early immature DC (iDC) and suppress T-cell responses. It is known that untreated monocytes injected into a recipient encounter a cytokine milieu which differentiates them to stimulatory DC. In our in vitro experiment MMC-treated monocytes cultured in a DC-maturing milieu transform themselves into suppressive early iDC. This reproduces a process which takes place when administering MMC-monocytes to a recipient. In conclusion, human MMC-DC or MMC-monocytes are not or only weakly suppressive in vitro. When MMC-monocytes are differentiated to DC the resulting cells become suppressive.  相似文献   
79.
  1. Butyrylcholinesterase (BChE) is a serine esterase that plays a role in the detoxification of natural as well as synthetic ester-bond-containing compounds. Alterations in BChE activity are associated with a number of diseases. Cholinergic system abnormalities in particular are correlated with the formation of senile plaques in Alzheimer’s disease (AD), and administration of cholinesterase inhibitors is a common therapeutic approach used to treat AD.

  2. Here, our aim was to study the interaction between BChE and fluoxetine.

  3. Molecular docking simulations revealed that fluoxetine penetrated deep into the active-site gorge of BChE and that it was engaged in stabilizing noncovalent interactions with multiple subsites. In substrate kinetic studies, the Vm, Km, kcat and kcat/Km values were found to be 20.59?±?0.36?U mg?1 protein, 194?±?14?µM, 1.3?×?108?s?1 and 6.7?×?105?µM?1s?1, respectively. Based on inhibitory studies, fluoxetine appeared to inhibit BChE competitively, with an IC50 value of 104?µM and a Ki value of 36.3?±?4.7?µM.

  4. Overall, both the low Ki value and the high number of BChE–fluoxetine interactions suggest that fluoxetine is a potent inhibitor of BChE, although in vivo mechanisms for the direct effects of BChE inhibition on various pathologies remain to be further investigated.

  相似文献   
80.
ObjectiveMethamphetamine is used extensively around the world as a psychostimulant. The complications related to methamphetamine include methamphetamine-induced neurotoxicity, mainly involving intraneuronal processes, such as oxidative stress and excitotoxicity. Curcumin is effective against neuronal injury due to its antioxidant, anti-inflammatory effects. In this study, we examined the protective effects of curcumin against methamphetamine neurotoxicity.MethodsSixty male Wistar rats were divided into the following groups: control (n = 12), DMSO (n = 12), methamphetamine (n = 12), and methamphetamine + curcumin (100 and 200 mg/kg, respectively, intraperitoneal [IP]; n = 12). Neurotoxicity was induced by 40 mg/kg of methamphetamine administrated through 4 injections (4 × 10 mg/kg, q2h, IP). Curcumin (100 and 200 mg/kg) was administered at 7 days after the last methamphetamine injection. By using a Morris water maze task, the hippocampus-dependent memory and spatial learning were evaluated 1 day after the last curcumin injection. Then, the animal brains were isolated for biochemical measurements, as well as glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor protein-1(Iba-1) and caspase-3 immunohistochemical staining.ResultsThe current study demonstrated that administration of curcumin significantly attenuates spatial memory impairment (P < 0.01) following methamphetamine neurotoxicity. Curcumin caused a significant increase in the levels of superoxide dismutase and glutathione peroxidase (P < 0.05). However, it decreased tumor necrosis factor (TNF-α) (P < 0.05) and malondialdehyde (P < 0.01) levels as compared to the methamphetamine group. Also, curcumin significantly reduced Iba-1 (P < 0. 01), GFAP and caspase-3 positive cells in the hippocampus (P < 0.001).ConclusionCurcumin exerted neuroprotective effects on methamphetamine neurotoxicity because of its antioxidant and anti-inflammatory effect.  相似文献   
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