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1.
Rett syndrome is a neurodevelopmental disorder caused by mutations of the methyl-CpG binding protein 2 gene. Abnormal physiological functions of glial cells contribute to pathogenesis of Rett syndrome. Semaphorin 4D (SEMA4D) regulates processes central to neuroinflammation and neurodegeneration including cytoskeletal structures required for process extension, communication, and migration of glial cells. Blocking SEMA4D-induced gliosis may preserve normal glial and neuronal function and rescue neurological dysfunction in Rett syndrome. We evaluated the pre-clinical therapeutic efficacy of an anti-SEMA4D monoclonal antibody in the Rett syndrome Mecp2T158A transgenic mouse model and investigated the contribution of glial cells as a proposed mechanism of action in treated mice and in primary glial cultures isolated from Mecp2T158A/y mutant mice. SEMA4D is upregulated in neurons while glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1-positive cells are upregulated in Mecp2T158A/y mice. Anti-SEMA4D treatment ameliorates Rett syndrome-specific symptoms and improves behavioural functions in both pre-symptomatic and symptomatic cohorts of hemizygous Mecp2T158A/y male mice. Anti-SEMA4D also reduces astrocyte and microglia activation in vivo. In vitro experiments demonstrate an abnormal cytoskeletal structure in mutant astrocytes in the presence of SEMA4D, while anti-SEMA4D antibody treatment blocks SEMA4D–Plexin B1 signaling and mitigates these abnormalities. These results suggest that anti-SEMA4D immunotherapy may be an effective treatment option to alleviate symptoms and improve cognitive and motor function in Rett syndrome.  相似文献   

2.
Intrauterine growth restriction (IUGR), predominantly caused by placental insufficiency, affects partitioning of nutrients to the fetus. The system A sodium-coupled transporters (SNAT or SLC38), of types A1, A2, and A4, control non-essential amino acid uptake and supply. Here, we aimed to investigate the expression of these transporters across different placental disease cohorts and cells. To determine disease impact, transporter expressions at the gene (qPCR) and protein (western blots) level were assessed in gestationally matched placental tissues. Early (<34 weeks), and late (34–36 weeks) onset IUGR cases with/out preeclampsia were compared to preterm controls. We also investigated level of transporter expression in primary trophoblasts under glucose deprivation (n = 6) and hypoxia conditions (n = 7). SLC38A4 protein was significantly downregulated in early preterm pregnancies complicated with IUGR with/out preeclampsia. There were no differences in late preterm IUGR cohorts. Furthermore, we demonstrate for the first time in primary trophoblast cells, that gene expression of the transporters was sensitive to and induced by glucose starvation. SLC38A4 mRNA expression was also significantly upregulated in response to hypoxia. Thus, SLC38A4 expression was persistently low in early preterm IUGR pregnancies, regardless of disease aetiology. This suggests that gestational age at delivery, and consequently IUGR severity, may influence loss of its expression.  相似文献   

3.
In the era of personalized medicine, insights into the molecular mechanisms that differentially contribute to disease phenotypes, such as asthma phenotypes including obesity-associated asthma, are urgently needed. Peripheral blood was drawn from 10 obese, non-atopic asthmatic adults with a high body mass index (BMI; 36.67 ± 6.90); 10 non-obese, non-atopic asthmatic adults with normal BMI (23.88 ± 2.73); and 10 healthy controls with normal BMI (23.62 ± 3.74). All asthmatic patients were considered to represent a low type-2 asthma phenotype according to selective clinical parameters. RNA sequencing (RNA-Seq) was conducted on peripheral blood CD4+ T cells. Thousands of differentially expressed genes were identified in both asthma groups compared with heathy controls. The expression of interferon (IFN)-stimulated genes associated with IFN-related signaling pathways was specifically affected in obese asthmatics, while the gap junction and G protein-coupled receptor (GPCR) ligand binding pathways were enriched in both asthma groups. Furthermore, obesity gene markers were also upregulated in CD4+ T cells from obese asthmatics compared with the two other groups. Additionally, the enriched genes of the three abovementioned pathways showed a unique correlation pattern with various laboratory and clinical parameters. The specific activation of IFN-related signaling and viral infection pathways might provide a novel view of the molecular mechanisms associated with the development of the low type-2 obesity-associated asthma phenotype, which is a step ahead in the development of new stratified therapeutic approaches.  相似文献   

4.
Monocarboxylate transporters (MCTs) are of great research interest for their role in cancer cell metabolism and their potential ability to transport pharmacologically relevant compounds across the membrane. Each member of the MCT family could potentially provide novel therapeutic approaches to various diseases. The major differences among MCTs are related to each of their specific metabolic roles, their relative substrate and inhibitor affinities, the regulation of their expression, their intracellular localization, and their tissue distribution. MCT4 is the main mediator for the efflux of L-lactate produced in the cell. Thus, MCT4 maintains the glycolytic phenotype of the cancer cell by supplying the molecular resources for tumor cell proliferation and promotes the acidification of the extracellular microenvironment from the co-transport of protons. A promising therapeutic strategy in anti-cancer drug design is the selective inhibition of MCT4 for the glycolytic suppression of solid tumors. A small number of studies indicate molecules for dual inhibition of MCT1 and MCT4; however, no selective inhibitor with high-affinity for MCT4 has been identified. In this study, we attempt to approach the structural characteristics of MCT4 through an in silico pipeline for molecular modelling and pharmacophore elucidation towards the identification of specific inhibitors as a novel anti-cancer strategy.  相似文献   

5.
Non-infectious uveitis (NIU) is a potentially sight-threatening disease. Effector CD4+ T cells, especially interferon-γ-(IFNγ) producing Th1 cells and interleukin-17-(IL-17) producing Th17 cells, are the major immunopathogenic cells, as demonstrated by adoptive transfer of disease in a model of experimental autoimmune uveitis (EAU). CD4+FoxP3+CD25+ regulatory T cells (Tregs) were known to suppress function of effector CD4+ T cells and contribute to resolution of disease. It has been recently reported that some CD4+ T-cell subsets demonstrate shared phenotypes with another CD4+ T-cell subset, offering the potential for dual function. For example, Th17/Th1 (co-expressing IFNγ and IL-17) cells and Th17/Treg (co-expressing IL-17 and FoxP3) cells have been identified in NIU and EAU. In this review, we have investigated the evidence as to whether these ‘plastic CD4+ T cells’ are functionally active in uveitis. We conclude that Th17/Th1 cells are generated locally, are resistant to the immunosuppressive effects of steroids, and contribute to early development of EAU. Th17/Treg cells produce IL-17, not IL-10, and act similar to Th17 cells. These cells were considered pathogenic in uveitis. Future studies are needed to better clarify their function, and in the future, these cell subsets may in need to be taken into consideration for designing treatment strategies for disease.  相似文献   

6.
Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.  相似文献   

7.
We have previously shown that a deficiency of CD1d-restricted invariant natural killer T (iNKT) cells exacerbates dextran sulfate sodium (DSS)-induced colitis in Yeti mice that exhibit IFNγ-mediated hyper-inflammation. Although iNKT cell-deficiency resulted in reduced Foxp3 expression by mesenteric lymph node (MLN) CD4+ T cells in DSS-treated Yeti mice, the cellular mechanisms that regulate Foxp3 expression by CD25+CD4+ T cells during intestinal inflammation remain unclear. We found that Foxp3CD25+CD4+ T cells expressing Th1 and Th17 phenotypic hallmarks preferentially expanded in the MLNs of DSS-treated Yeti/CD1d knockout (KO) mice. Moreover, adoptive transfer of Yeti iNKT cells into iNKT cell-deficient Jα18 KO mice effectively suppressed the expansion of MLN Foxp3CD25+CD4+ T cells during DSS-induced colitis. Interestingly, MLN dendritic cells (DCs) purified from DSS-treated Yeti/CD1d KO mice promoted the differentiation of naive CD4+ T cells into Foxp3CD25+CD4+ T cells rather than regulatory T (Treg) cells, indicating that MLN DCs might mediate Foxp3+CD25+CD4+ T cell expansion in iNKT cell-sufficient Yeti mice. Furthermore, we showed that Foxp3CD25+CD4+ T cells were pathogenic in DSS-treated Yeti/CD1d KO mice. Our result suggests that pro-inflammatory DCs and CD1d-restricted iNKT cells play opposing roles in Foxp3 expression by MLN CD25+CD4+ T cells during IFNγ-mediated intestinal inflammation, with potential therapeutic implications.  相似文献   

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9.
The accumulation of specific metabolic intermediates is known to promote cancer progression. We analyzed the role of 4-pyridone-3-carboxamide-1-β-D-ribonucleoside (4PYR), a nucleotide metabolite that accumulates in the blood of cancer patients, using the 4T1 murine in vivo breast cancer model, and cultured cancer (4T1) and endothelial cells (ECs) for in vitro studies. In vivo studies demonstrated that 4PYR facilitated lung metastasis without affecting primary tumor growth. In vitro studies demonstrated that 4PYR affected extracellular adenine nucleotide metabolism and the intracellular energy status in ECs, shifting catabolite patterns toward the accumulation of extracellular inosine, and leading to the increased permeability of lung ECs. These changes prevailed over the direct effect of 4PYR on 4T1 cells that reduced their invasive potential through 4PYR-induced modulation of the CD73-adenosine axis. We conclude that 4PYR is an oncometabolite that affects later stages of the metastatic cascade by acting specifically through the regulation of EC permeability and metabolic controls of inflammation.  相似文献   

10.
The evolutionary conserved ESCRT-III complex is a device for membrane remodelling in various cellular processes, such as the formation of intraluminal vesicles (ILVs), cytokinesis, and membrane repair. The common theme of all these processes is the abscission of membrane away from the cytosol. At its heart in Drosophila is Shrub, CHMP4 in humans, which dynamically polymerises into filaments through electrostatic interactions among the protomers. For the full activity, Shrub/CHMP4 requires physical interaction with members of the Lgd protein family. This interaction is mediated by the odd-numbered DM14 domains of Lgd, which bind to the negative interaction surface of Shrub. While only one Lgd and one Shrub exist in the genome of Drosophila, mammals have two Lgd orthologs, LGD1/CC2D1B and LGD2/CC2D1A, as well as three CHMP4s in their genomes, CHMP4A, CHMP4B, and CHMP4C. The rationale for the diversification of the ESCRT components is not understood. We here use Drosophila as a model system to analyse the activity of the human orthologs of Shrub and Lgd at an organismal level. This enabled us to use the plethora of available techniques available for Drosophila. We present evidence that CHMP4B is the true ortholog of Shrub, while CHMP4A and CHMP4C have diverging activities. Nevertheless, CHMP4A and CHMP4C can enhance the activity of CHMP4B, raising the possibility that they can form heteropolymers in vivo. Our structure-function analysis of the LGD1 and LGD2 indicates that the C2 domain of the LGD proteins has a specific function beyond protein stability and subcellular localisation. Moreover, our data specify that CHMP4B interacts more efficiently with LGD1 than with LGD2.  相似文献   

11.
目的观察甲型H1N1流感患者病毒核酸阴转时限。方法选择2009年9月16~27日我院收治的甲型H1N1流感确诊病例38例,经同一名医生进行咽拭子采集,采用RT-PCR方法检测甲型通用、甲1通用、季节性流感、甲型H1N1亚型4个病毒亚型,以甲型通用、甲1通用、甲型H1N1亚型均阴转作为判定病毒核酸阴转的标准。结果 38例甲型H1N1流感患者病毒核酸阴转的时限最短1 d,最长14 d,平均4.5 d;病毒核酸阴转时间主要集中在第3、4、5天,第5天与第4天相比,甲型通用、甲1通用和甲型H1N1的阴转比例均明显增加(P<0.05);发病36 h内接受抗病毒治疗者,病毒核酸阴转平均时间为4.1 d;37~72 h接受抗病毒治疗者,病毒核酸阴转平均时间为5.2 d;有3例甲型通用、甲1通用、甲型H1N1亚型病毒核酸未同时阴转。结论甲型H1N1流感抗病毒治疗1周,大部分患者病毒核酸阴转,不具有传染性;尽早(36 h内)接受抗病毒治疗,可以缩短病毒核酸阴转时间;甲型通用、甲1通用、甲型H1N1亚型具有较好的一致性,对三者未同时阴转的情况,应注意是否同时合并其他甲型流感病毒亚型感染。  相似文献   

12.
13.
宋静明  张静 《云南化工》2020,(1):42-43+45
胡尖山地区长4+5油层组储层非均质性强、物性差异较大,开展该区储层地质特征研究,尤其是针对胡尖山地区长4+5油层组的构造形态、储层特征、孔隙类型、油藏类型的研究,分析原油的分布特征,总结原油富集区的聚集特征、重点分析分布特征及控制因素,得到胡尖山地区长4+5层油气富集的规律,可加深对优质储层形成机理和分布规律的认识,为油藏勘探开发提供有利的方向。  相似文献   

14.
以内蒙古某地的煤矸石为原料,采用低温(450 ℃)碱融活化法对样品进行活化,并添加导向剂水热合成4A沸石。实验在30~60 ℃的低温晶化条件下进行,晶化时间为24 h。利用XRD、SEM、FT-IR和BET等测试手段对不同温度下生成的4A沸石加以表征,间接地评价生成沸石的质量。结果表明,在晶化温度为30 ℃时,样品中便有少量的4A沸石生成;当温度达到50 ℃时,即可得到形态较佳、粒径约为2 μm且结晶度较好的4A沸石。  相似文献   

15.
Fetal programming implies that the maternal diet during pregnancy affects the long-term health of offspring. Although maternal diet influences metabolic disorders and non-alcoholic fatty liver disease in offspring, the hepatic mechanisms related to metabolites are still unknown. Here, we investigated the maternal diet-related alterations in metabolites and the biological pathway in male offspring at three months of age. Pregnant rats were exposed to 50% food restriction during the prenatal period or a 45% high-fat diet during the prenatal and postnatal periods. The male offspring exposed to food restriction and high-fat diets had lower birth weights than controls, but had a catch-up growth spurt at three months of age. Hepatic taurine levels decreased in both groups compared to controls. The decreased hepatic taurine levels in offspring affected excessive lipid accumulation through changes in hepatocyte nuclear factor 4 A methylation. Moreover, the alteration of gluconeogenesis in offspring exposed to food restriction was observed to a similar extent as that of offspring exposed to a high fat diet. These results indicate that maternal diet affects the dysregulation in hepatic metabolism through changes in taurine levels and HNF4A methylation, and predisposes the offspring to Type 2 diabetes and non-alcoholic fatty liver disease in later life.  相似文献   

16.
A PAN-4A composite ion exchanger containing about 80% 4A powder was prepared to remove strontium and cesium ions from acidic solution. The SEM image of the fracture of composite bead showed that zeolite 4A powder was dispersed homogenously and the pores were well formed. The mean pore size of composite bead was 0.14 μm and its porosity was about 74%, which is much higher in comparison with the existing inorganic adsorbent beads. The acid and radiation stability tests showed that PAN-4A was stable against acid solution higher than pH 2 and radiation dose less than 1.89×108 rad, respectively. Ion exchange tests showed that the PAN-4A was selective for Sr ion. The distribution coefficients of PAN-4A for Sr and Cs ions at pH 2 were 2×104 mL/g and 280 mL/g, respectively. The ion exchange capacities (qs) of PAN-4A for Sr and Cs ions at pH 2, which are modeled by Dubinin-Polanyi equation, were 3.92 meq/g and 2.47 meq/g, respectively.  相似文献   

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18.
B-cell chronic lymphocytic leukemia (CLL) results from intrinsic genetic defects and complex microenvironment stimuli that fuel CLL cell growth through an array of survival signaling pathways. Novel small-molecule agents targeting the B-cell receptor pathway and anti-apoptotic proteins alone or in combination have revolutionized the management of CLL, yet combination therapy carries significant toxicity and CLL remains incurable due to residual disease and relapse. Single-molecule inhibitors that can target multiple disease-driving factors are thus an attractive approach to combat both drug resistance and combination-therapy-related toxicities. We demonstrate that SRX3305, a novel small-molecule BTK/PI3K/BRD4 inhibitor that targets three distinctive facets of CLL biology, attenuates CLL cell proliferation and promotes apoptosis in a dose-dependent fashion. SRX3305 also inhibits the activation-induced proliferation of primary CLL cells in vitro and effectively blocks microenvironment-mediated survival signals, including stromal cell contact. Furthermore, SRX3305 blocks CLL cell migration toward CXCL-12 and CXCL-13, which are major chemokines involved in CLL cell homing and retention in microenvironment niches. Importantly, SRX3305 maintains its anti-tumor effects in ibrutinib-resistant CLL cells. Collectively, this study establishes the preclinical efficacy of SRX3305 in CLL, providing significant rationale for its development as a therapeutic agent for CLL and related disorders.  相似文献   

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20.
Guanylate cyclase-activating protein 1 (GCAP1), encoded by the GUCA1A gene, is a neuronal calcium sensor protein involved in shaping the photoresponse kinetics in cones and rods. GCAP1 accelerates or slows the cGMP synthesis operated by retinal guanylate cyclase (GC) based on the light-dependent levels of intracellular Ca2+, thereby ensuring a timely regulation of the phototransduction cascade. We found a novel variant of GUCA1A in a patient affected by autosomal dominant cone dystrophy (adCOD), leading to the Asn104His (N104H) amino acid substitution at the protein level. While biochemical analysis of the recombinant protein showed impaired Ca2+ sensitivity of the variant, structural properties investigated by circular dichroism and limited proteolysis excluded major structural rearrangements induced by the mutation. Analytical gel filtration profiles and dynamic light scattering were compatible with a dimeric protein both in the presence of Mg2+ alone and Mg2+ and Ca2+. Enzymatic assays showed that N104H-GCAP1 strongly interacts with the GC, with an affinity that doubles that of the WT. The doubled IC50 value of the novel variant (520 nM for N104H vs. 260 nM for the WT) is compatible with a constitutive activity of GC at physiological levels of Ca2+. The structural region at the interface with the GC may acquire enhanced flexibility under high Ca2+ conditions, as suggested by 2 μs molecular dynamics simulations. The altered interaction with GC would cause hyper-activity of the enzyme at both low and high Ca2+ levels, which would ultimately lead to toxic accumulation of cGMP and Ca2+ in the photoreceptor outer segment, thus triggering cell death.  相似文献   

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