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1.
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities.  相似文献   
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Polylactic acid(PLA)possesses good mechanical and biodegradability properties which make it a suitable material for polymer composites whereas brittleness and high costs limit its utilization in various applications.The reinforcement of natural fibres with biopolymers has been formed to be an efficient technique to develop composites having the ability to be fully biodegradable.This study concerns with the incorporation of various percentages of untreated and alkali-treated Coir Fibres(CF)and pineapple leaf fibres(PALF)in PLA biocomposites and characterizations of flexural,morphological and dynamic mechanical properties.Flexural properties showed that the treated C1P1 hybrid composites(C1P1A)displayed highest flexural strength(35.81 MPa)and modulus(5.28 GPa)among all hybrid biocomposites.Scanning Electron Micros-copy(SEM)revealed a behaviour of fibre-matrix adhesion in untreated treated biocomposites.SEM observation revealed good dispersion of the fillers in PLA.Dynamic mechanical analysis revealed that C1P1A showed highest glass transition temperature(Tg)and storage modulus(E')while untreated C3P7 displayed the least Tg and E'.Overall findings showed that alkali-treated hybrid biocomposites(CF/PALF/PLA)especially C1P1A have improved flexural properties,dynamic and morphological properties over untreated biocomposites.Success of these findings will provide attracting consideration of these hybrid biocomposites for various lightweight uses in a broad selection of industrial applications such as biomedical sectors,automobile,construction,electronics equipment,and hardware tools.  相似文献   
4.
G Quash  H Ripoll  L Gazzolo  A Doutheau  A Saba  J Gore 《Biochimie》1987,69(2):101-108
The oxidation of spermine in vitro by a mixture of polyamine oxidase and diamine oxidase from pig kidney gives rise to malondialdehyde via 3-aminopropanol as the intermediate. Conversely, with spermidine, under similar experimental conditions, no evidence could be obtained for malondialdehyde formation within the limits of sensitivity of the assay (2.0 nmol). The activities of both these enzymes show about a 2-fold increase in normal rat kidney cells (LA31 NRK) transformed by the temperature sensitive mutant of Rous sarcoma virus (LA31) and incubated at the non permissive temperature (39 degrees C) compared to the activities in LA31 NRK at the permissive temperature (33 degrees C). These same enzymatic activities show no temperature dependent changes in normal rat kidney cells (NRK) or in these same cells infected by the wild type virus (NRK B77). In extracts derived from Friend erythroleukemic cells induced to differentiate by dimethyl sulfoxide or hexamethylene bis acetamide, spermine oxidation takes place more efficiently than in non induced cells. A rise in diamine oxidase activity is seen in LA31 NRK (39 degrees C) 12 h after the temperature shift, whereas morphological manifestations of normalcy are seen only at 48 h. The Km of diamine oxidase is 10(-6) M for putrescine and 10(-3) M for 3-aminopropanol. A possible mechanism involving the well documented acetylation of putrescine [23,26] is proposed for diverting intracellular putrescine away from cytosolic diamine oxidase and towards intramitochondrial monoamine oxidase.  相似文献   
5.
Globe artichoke (Cynara cardunculus L. var. scolymus L.) is a diploid (2n=2x=34), predominantly cross-pollinated plant native to the Mediterranean basin, and Italy contains the richest primary cultivated gene pool. Commercial production is mainly based on perennial cultivation of vegetatively propagated clones that are highly heterozygous and segregate widely when progeny-tested. Analysis of the artichoke genome by means of molecular markers has been limited to a few studies; here we report on the genetic relatedness among 118 artichoke accessions, including clones belonging to the same varietal type, two accessions of cultivated cardoon (C. cardunculus L. var. altilis DC.) and four accessions of wild cardoon [C. cardunculus L. var. sylvestris (Lamk) Fiori] as measured by amplified fragment length polymorphism (AFLP). Eight primer combinations yielded a total of 667 bands, of which 519 were polymorphic. Genetic similarities among accessions were calculated according to Jaccards Similarity Index and used to construct a dendrogram based on the unweighted pair group method using arithmetic averages. Our results demonstrate that AFLP markers can be useful in evaluating Cynara cardunculus genetic diversity and in classifying accessions to phylogenetic groups based on their genetic similarity values. Genetic variation among artichoke clones belonging to the same varietal type was in some cases higher than that found among accessions differently named and coming from different areas. The lowest Jaccards Similarity Index found within a varietal type can be considered as a threshold for the identification of accessions which share an analogous genetic background. This will enable the selection of representatives in order to develop and manage a germplasm core collection as well as the identification of suitable material for future artichoke breeding efforts.Communicated by J.S. Heslop-Harrison  相似文献   
6.
Opioid use disorder (OUD) is an ongoing public health concern in the United States, and relatively little work has addressed how genetic background contributes to OUD. Understanding the genetic contributions to oxycodone-induced analgesia could provide insight into the early stages of OUD development. Here, we present findings from a behavioral phenotyping protocol using several inbred strains from the Hybrid Rat Diversity Panel. Our behavioral protocol included a modified “up-down” von Frey procedure to measure inherent strain differences in the sensitivity to a mechanical stimulus on the hindpaw. We also performed the tail immersion assay, which measures the latency to display tail withdrawal in response to a hot water bath. Initial withdrawal thresholds were taken in drug-naïve animals to record baseline thermal sensitivity across the strains. Oxycodone-induced analgesia was measured after administration of oxycodone over the course of 2 h. Both mechanical and thermal sensitivity are shaped by genetic factors and display moderate heritability (h2 = 0.23–0.40). All strains displayed oxycodone-induced analgesia that peaked at 15–30 min and returned to baseline by 2 h. There were significant differences between the strains in the magnitude and duration of their analgesic response to oxycodone, although the heritability estimates were quite modest (h2 = 0.10–0.15). These data demonstrate that genetic background confers differences in mechanical sensitivity, thermal sensitivity, and oxycodone-induced analgesia.  相似文献   
7.
Inferring gene co-expression networks is a useful process for understanding gene regulation and pathway activity. The networks are usually undirected graphs where genes are represented as nodes and an edge represents a significant co-expression relationship. When expression data of multiple (p) genes in multiple (K) conditions (e.g., treatments, tissues, strains) are available, joint estimation of networks harnessing shared information across them can significantly increase the power of analysis. In addition, examining condition-specific patterns of co-expression can provide insights into the underlying cellular processes activated in a particular condition. Condition adaptive fused graphical lasso (CFGL) is an existing method that incorporates condition specificity in a fused graphical lasso (FGL) model for estimating multiple co-expression networks. However, with computational complexity of O(p2K log K), the current implementation of CFGL is prohibitively slow even for a moderate number of genes and can only be used for a maximum of three conditions. In this paper, we propose a faster alternative of CFGL named rapid condition adaptive fused graphical lasso (RCFGL). In RCFGL, we incorporate the condition specificity into another popular model for joint network estimation, known as fused multiple graphical lasso (FMGL). We use a more efficient algorithm in the iterative steps compared to CFGL, enabling faster computation with complexity of O(p2K) and making it easily generalizable for more than three conditions. We also present a novel screening rule to determine if the full network estimation problem can be broken down into estimation of smaller disjoint sub-networks, thereby reducing the complexity further. We demonstrate the computational advantage and superior performance of our method compared to two non-condition adaptive methods, FGL and FMGL, and one condition adaptive method, CFGL in both simulation study and real data analysis. We used RCFGL to jointly estimate the gene co-expression networks in different brain regions (conditions) using a cohort of heterogeneous stock rats. We also provide an accommodating C and Python based package that implements RCFGL.  相似文献   
8.
The human retinal pigment epithelium-specific 65-kDa protein (hRPE65) plays a crucial role within the retinoid visual cycle and several mutations affecting either its expression level or its enzymatic function are associated with inherited retinal diseases such as Retinitis Pigmentosa. The gene therapy product voretigene neparvovec (Luxturna) has been recently approved for treating hereditary retinal dystrophies; however, the treatment is currently accessible only to patients presenting confirmed biallelic mutations that severely impair hRPE65 function, and many reported hRPE65 missense mutations lack sufficient evidences for proving their pathogenicity. In this context, we developed a computational approach aimed at evaluating the potential pathogenic effect of hRPE65 missense variants located on the dimerisation domain of the protein. The protocol evaluates how mutations may affect folding and conformation stability of this protein region, potentially helping clinicians to evaluate the eligibility for gene therapy of patients diagnosed with this type of hRPE65 variant of uncertain significance.  相似文献   
9.
Most solid tumors are aneuploid, carrying an abnormal number of chromosomes, and they frequently missegregate whole chromosomes in a phenomenon termed chromosome instability (CIN). While CIN can be provoked through disruption of numerous mitotic pathways, it is not clear which of these mechanisms are most critical, or whether alternative mechanisms could also contribute significantly in vivo. One difficulty in determining the relative importance of candidate CIN regulators has been the lack of a straightforward, quantitative assay for CIN in live human cells: While gross mitotic abnormalities can be detected visually, moderate levels of CIN may not be obvious, and are thus problematic to measure. To address this issue, we have developed the first Human Artificial Chromosome (HAC)-based quantitative live-cell assay for mitotic chromosome segregation in human cells. We have produced U2OS-Phoenix cells carrying the alphoidtetO-HAC encoding copies of eGFP fused to the destruction box (DB) of anaphase promoting complex/cyclosome (APC/C) substrate hSecurin and sequences encoding the tetracycline repressor fused to mCherry (TetR-mCherry). Upon HAC missegregation, daughter cells that do not obtain a copy of the HAC are GFP negative in the subsequent interphase. The HAC can also be monitored live following the TetR-mCherry signal. U2OS-Phoenix cells show low inherent levels of CIN, which can be enhanced by agents that target mitotic progression through distinct mechanisms. This assay allows direct detection of CIN induced by clinically important agents without conspicuous mitotic defects, allowing us to score increased levels of CIN that fall below the threshold required for discernable morphological disruption.  相似文献   
10.
Due to concerns about data quality, McKechnie, Coe, Gerson, and Wolf ( 2016 ) questioned the conclusions of our study (Khaliq et al., 2015 ) published in this journal. Here, we argue that most of the questioned data points are in fact useful for macrophysiological analyses, mostly because the vast majority of data are explicitly reported in the peer‐reviewed physiological literature. Furthermore, we show that our conclusions remain largely robust irrespective of the data inclusion criterion. While we think that constructive debates about the adequate use of primary data in meta‐studies as well as more transparency in data inclusion criteria are indeed useful, we also emphasize that data suitability should be evaluated in the light of the scope and scale of the study in which they are used. We hope that this discussion will not discourage the exchange between disciplines such as biogeography and physiology, as this integration is needed to address some of the most urgent scientific challenges.  相似文献   
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