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1.
J Microbiol Methods ; 169: 105832, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31904439

RESUMO

Cell growth of lactic acid bacteria is of vital importance in starter culture manufacture in the dairy industry. However, one of the major stumbling blocks in the understanding of bacterial cell growth relates to challenges in the quantification of the cell division or death. To overcome these shortcomings, the intracellular fluorescent cell tracking assay was implemented to monitor Lactobacillus delbrueckii subsp. bulgaricus sp1.1 cell division and death. Optimization of fluorescent dye concentration suggested it could be applied in the tracking of cell division without cytotoxicity. Technical validation of the fluorescent tracking demonstrated this assay was accurate for quantitatively analyzing cell division. Furthermore, the cell death was quantified using the precursor cohort distribution of the time-series fluorescence data in batch culture. The results indicated a dynamic and unbalanced relationship between bacterial cell division and death after exponential phase in the batch culture. These findings suggested that fluorescent dye tracking is a powerful tool for monitoring L. bulgaricus sp1.1 cell division and death and can provide valuable information for bacterial growth behavior in batch culture.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31902756

RESUMO

Layout is important for graphic design and scene generation. We propose a novel Generative Adversarial Network, called LayoutGAN, that synthesizes layouts by modeling geometric relations of different types of 2D elements. The generator of LayoutGAN takes as input a set of randomly-placed 2D graphic elements, represented by vectors and uses self-attention modules to refine their labels and geometric parameters jointly to produce a realistic layout. Accurate alignment is critical for good layouts. We thus propose a novel differentiable wireframe rendering layer that maps the generated layout to a wireframe image, upon which a CNN-based discriminator is used to optimize the layouts in image space. We validate the effectiveness of LayoutGAN in various experiments including MNIST digit generation, document layout generation, clipart abstract scene generation, tangram graphic design, mobile app layout design, and webpage layout optimization from hand-drawn sketches.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31818093

RESUMO

Graphene aerogel (GA) as a rising multifunctional material has demonstrated great potential for energy storage and conversion, environmental remediation, high-performance sensors or actuators. However, the commercial use of GA is obstructed by its fragility and high-cost. Herein, by a simple stirring-induced foaming of the mixed aqueous solutions of natural rubber latex (NRL) and graphene oxide liquid crystal (GOLC), we obtained tough, ultralight (4.6 mg cm-3), high compressibility (> 90%) and water-adhesive graphene/NRL hybrid aerogel (GA/NRL). Of particular note, the NRL particles are conformally wrapped by graphene layers to form the sandwich-like cell wall with biomimetic rose petal surface. These distinct hierarchical structures endow GA/NRL not only high toughness to bear the impact, torsion (> 90°) and even ultrasonication but also strong adhesion to water. As a proof of concept, the utilization of the as-prepared GA/NRL to collect water droplets suspending in the moist air and its improved solar-thermal harvest capacity have been demonstrated. This facile, green and cost-effective strategy opens a new route for tailoring the microstructure and functionality of GA, which will facilitate its large-scale production and commercial application.

4.
Mikrochim Acta ; 186(12): 794, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31734780

RESUMO

A photoelectrochemical (PEC) aptasensor is described for detecting tetracycline (TC). A gold nanoparticles/BiOBr (AuNPs/BiOBr) composite was prepared where the AuNPs play a key function in carrier transfer which is ascribed to the wavelength-dependent dual function as an electron sink and as a hot-electron donor. Due to this dual function, the composite exhibits a wide photo-response and high electron transfer efficiency. This results in enormously enhanced PEC response. The TC-aptamer was immobilized on an ITO modified with AuNPs/BiOBr via Au-S covalent bonding. The resulting PEC aptasensor possesses a wide linear range (1-104 ng L-1) and a low detection limit (0.35 ng L-1; at S/N = 3). Graphical abstractSchematic representation of a photoelectrochemical aptasensor for tetracycline based on the use of a AuNP/BiOBr composite with electron sink and hot-electron donor properties of the gold nanoparticles.

5.
Ann Vasc Surg ; 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31743780

RESUMO

BACKGROUND/OBJECTIVES: The acute exacerbations and progressive deterioration seen in thromboangiitis obliterans (TAO) have been related to poor clinical outcomes. Here, we have studied the association of laboratory biomarkers with the acute phase of TAO (AP-TAO). METHODS/RESULTS: We conducted a retrospective case-control study on 112 patients with TAO and 98 healthy controls; comparing the neutrophil-to-lymphocyte rate (NLR), lymphocyte-to-monocyte rate (LMR), platelet-to-neutrophil rate (PNR), fibrinogen (FIB) and apolipoprotein A-I (ApoA-I). Significantly higher NLR level, as well as lower LMR, PNR, ApoA-I levels were observed in patients with TAO, particularly the acute phase. Significantly increased FIB was only observed in AP-TAO. A positive correlation was found between NLR and with C-reactive protein (CRP) in the acute phase (r=0.817, p<0.001). Moreover, NLR, PNR and FIB levels of 3.38, 45.12 and 3.69 were shown to be the predictive cut-off values for the AP-TAO (sensitivity 72.5, 82,4 and 66,7%, specificity 92.2, 78.4 and 96.1%; area under the curve (AUC) 0.875, 0.855 and 0.872), respectively. FIB level was independently associated with the AP-TAO (OR = 11.420, p=0.007). CONCLUSIONS: NLR, PNR and FIB may be useful markers for the identification of inflammation and the AP-TAO. FIB may be an independent risk factor for the acute phase.

6.
Cell Commun Signal ; 17(1): 125, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31610798

RESUMO

BACKGROUND: Aberrant expression of cyclin-dependent protein kinases (CDK) is a hallmark of cancer. CDK11 plays a crucial role in cancer cell growth and proliferation. However, the molecular mechanisms of CDK11 and CDK11 transcriptionally regulated genes are largely unknown. METHODS: In this study, we performed a global transcriptional analysis using gene array technology to investigate the transcriptional role of CDK11 in osteosarcoma. The promoter luciferase assay, chromatin immunoprecipitation assay, and Gel Shift assay were used to identify direct transcriptional targets of CDK11. Clinical relevance and function of core-binding factor subunit beta (CBFß) were further accessed in osteosarcoma. RESULTS: We identified a transcriptional role of protein-DNA interaction for CDK11p110, but not CDK11p58, in the regulation of CBFß expression in osteosarcoma cells. The CBFß promoter luciferase assay, chromatin immunoprecipitation assay, and Gel Shift assay confirmed that CBFß is a direct transcriptional target of CDK11. High expression of CBFß is associated with poor outcome in osteosarcoma patients. Expression of CBFß contributes to the proliferation and metastatic behavior of osteosarcoma cells. CONCLUSIONS: These data establish CBFß as a mediator of CDK11p110 dependent oncogenesis and suggest that targeting the CDK11- CBFß pathway may be a promising therapeutic strategy for osteosarcoma treatment.

7.
Chem Commun (Camb) ; 55(91): 13737-13740, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31661086

RESUMO

A highly transparent and stretchable electrode based on a Au nanomesh, electrodeposited with a thin layer of MnO2 with a transparency of 84.7% is introduced. The as-prepared transparent, stretchable, and imperceptible supercapacitor (TSPS) exhibits a specific capacitance of 0.53 mF cm-2 and excellent bending stability, together with high stretchability (up to 160% strain).

8.
Cell Commun Signal ; 17(1): 138, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31665012

RESUMO

Following publication of the original article [1], it was reported that Figs. 4 and 5 were not updated during the production process.

9.
Carbohydr Polym ; 225: 115230, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521261

RESUMO

Rigid chitin nanofibers (ChNFs) self-assembled from dilute α-chitin/KOH/urea aqueous solution were utilized as 1D filler to reinforce soft natural rubber (NR). The prepared ChNFs suspension has good compatibility with natural rubber latex (NRL) and thus showing favorable dispersibility in NR matrix at nanoscale. The bio-nanocomposites were fabricated by casting and evaporating the pre-mixed NRL/ChNFs suspensions with different ChNFs loadings. Gratifyingly, the NR/ChNFs bio-nanocomposite with only 0.3 wt% ChNFs content presented distinct improvement in both the strength and toughness due to the large aspect ratio of ChNFs and its homogeneous dispersion in NRL matrix. Moreover, the introduction of ChNFs can promote the proliferation of mBMSCs effectively and endow NR/ChNFs bio-nanocomposites with good biocompatibility, enabling expanded applications of NR in biomedical field, such as artificial blood vessel, cosmetology prosthesis and human diaphragm materials.

10.
J Pak Med Assoc ; 69(9): 1344-1348, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31511722

RESUMO

OBJECTIVE: To determine the therapeutic effects of pre-admission ticagrelor in acute ST elevation myocardial infarction after primary percutaneous coronary intervention. METHODS: The meta analysis was conducted at the period from the establishment of the database to the February 2018 period, and comprised earlier studies that were selected after comprehensive search of PubMed, Medline, Excerpta Medica dataBASE and Cochrane databases. The studies compared the pre-treatment group (pre-hospital ticagrelor) with the control group (in-hospital ticagrelor) and found differences in primary percutaneous coronary intervention outcomes for sick individuals suffering from acute ST elevation myocardial infarction. RESULTS: The two studies selected together had 1915 subjects. The rate of stent thrombosis in the control group was higher than in the pre-treatment group (p<0.01), but there were no significant differences in all-cause mortality (p=0.88), myocardial infarction (p=0.17) and stroke (p=0.49). CONCLUSIONS: Pre-hospital ticagrelor decreased the incidence of stent thrombosis in patients with acute ST elevation myocardial infarction who underwent primary percutaneous coronary intervention.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31514124

RESUMO

Detecting segments of interest from videos is a common problem for many applications. And yet it is a challenging problem as it often requires not only knowledge of individual target segments, but also contextual understanding of the entire video and the relationships between the target segments. To address this problem, we propose the Sequence-to-Segments Network (S2N), a novel and general end-to-end sequential encoder-decoder architecture. S2N first encodes the input video into a sequence of hidden states that capture information progressively, as it appears in the video. It then employs the Segment Detection Unit (SDU), a novel decoding architecture, that sequentially detects segments. At each decoding step, the SDU integrates the decoder state and encoder hidden states to detect a target segment. During training, we address the problem of finding the best assignment of predicted segments to ground truth using the Hungarian Matching Algorithm with Lexicographic Cost. Additionally, we propose to use the squared Earth Mover's Distance to optimize the localization errors of the segments. We show the state-of-the-art performance of S2N across numerous tasks, including video highlighting, video summarization, and human action proposal generation.

12.
J Hum Genet ; 64(11): 1067-1073, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31427716

RESUMO

Megacystis-microcolon-intestinal-hypoperistalsis syndrome (MMIHS) is a rare and severe disorder characterized by functional obstruction in the urinary and gastrointestinal tract. The molecular basis of this condition has been defined recently. Heterozygous variants in ACTG2, homozygous mutations in LMOD1, MYLK, and MYH9 were related to the pathogenesis of the syndrome, which encodes proteins involved in the process of smooth muscle contraction, supporting a myopathic basis for the disease. Recent studies have identified homozygous or compound heterozygous variants in MYH11 as a candidate gene of MMIHS. In this report, we described a nonconsanguineous Chinese family with three male fetuses affected with megacystis. Trio-targeted exome sequencing identified compound heterozygous variants, c.2051 G > A (p.R684H) and c.3540_3541delinsTT (p.(E1180D, Q1181Ter)), in MYH11 (NM_001040114). The variants were inherited from the parents, respectively. Western blotting showed a marked decrease in MYH11 protein in the proband's umbilical cord tissue compared with the control sample. The study's results confirmed that MYH11 is a candidate gene for MMIHS with autosomal recessive (AR) inheritance and expanded the mutation spectrum for this clinical condition. Combining clinical phenotype with molecular diagnosis may enable the identification of candidate genes for potential monogenic diseases and facilitate accurate genetic counseling, informed decision-making, and prenatal diagnosis.

13.
Br J Pharmacol ; 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31364164

RESUMO

BACKGROUND AND PURPOSE: Bruton's tyrosine kinase (BTK) plays a key role in B-cell receptor signalling by regulating cell proliferation and survival in various B-cell malignancies. Covalent low-MW BTK kinase inhibitors have shown impressive clinical efficacy in B-cell malignancies. However, the mutant BtkC481S poses a major challenge in the management of B-cell malignancies by disrupting the formation of the covalent bond between BTK and irreversible inhibitors, such as ibrutinib. The present studies were designed to develop novel BTK inhibitors targeting ibrutinib-resistant BtkC481S mutation. EXPERIMENTAL APPROACH: BTK-Ba/F3, BTK(C481S)-Ba/F3 cells, and human malignant B-cells JeKo-1, Ramos, and NALM-6 were used to evaluate cellular potency of BTK inhibitors. The in vitro pharmacological efficacy and compound selectivity were assayed via cell viability, colony formation, and BTK-mediated signalling. A tumour xenograft model with BTK-Ba/F3, Ramos and BTK(C481S)-Ba/F3 cells in Nu/nu BALB/c mice was used to assess in vivo efficacy of XMU-MP-3. KEY RESULTS: XMU-MP-3 is one of a group of low MW compounds that are potent non-covalent BTK inhibitors. XMU-MP-3 inhibited both BTK and the acquired mutant BTKC481S, in vitro and in vivo. Further computational modelling, site-directed mutagenesis analysis, and structure-activity relationships studies indicated that XMU-MP-3 displayed a typical Type-II inhibitor binding mode. CONCLUSION AND IMPLICATIONS: XMU-MP-3 directly targets the BTK signalling pathway in B-cell lymphoma. These findings establish XMU-MP-3 as a novel inhibitor of BTK, which could serve as both a tool compound and a lead for further drug development in BTK relevant B-cell malignancies, especially those with the acquired ibrutinib-resistant C481S mutation.

14.
Adv Mater ; 31(35): e1902955, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31268581

RESUMO

The next generation of flexible electronics will require highly stretchable and transparent electrodes, many of which consist of a relatively stiff metal network (or carbon materials) and an underlying soft substrate. Typically, such a stiff-soft bilayer suffers from wrinkling or folding when subjected to strains, causing high surface roughness and seriously deteriorated optical transparency. In this work, a network with a giant effective Poisson's ratio on a soft substrate is found to be under biaxial tension upon deformation, and thus does not wrinkle or fold, but maintains smooth surfaces and high transparency. Soft tactile sensors employing such network electrodes exhibit high transparency and low fatigue over many stretching cycles. Such a giant Poisson's ratio has the same effect in other systems. This work offers a new understanding of surface instabilities and a general strategy to prevent them not only in flexible electronics, but also in other materials and mechanical structures that require flat surfaces.

15.
J Exp Clin Cancer Res ; 38(1): 296, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288861

RESUMO

BACKGROUND: Karyopherin nuclear transport receptors play important roles in tumour development and drug resistance and have been reported as potential biomarkers and therapeutic targets for tumour treatment. However, IPO5, one of the karyopherin nuclear transport receptor family members, remains largely uncharacterized in tumour progression. METHODS: The TCGA data, quantitative reverse transcription-PCR (qRT-PCR), western blotting, and IHC analyses were used to detect IPO5 expression in CRC tissues. A series of in vivo and in vitro experiments was utilized to demonstrate the function of IPO5 in CRC tissues. Mass spectrometry (MS), CO-IP technology, subcellular fractionation, and immunofluorescence were utilized to investigate the possible mechanisms of CRC. RESULTS: IPO5 was highly expressed and positively correlated with the clinicopathological characteristics of colorectal cancer tissues. Functional experiments indicated that IPO5 could promote the development of CRC. Mechanistically, we screened RASAL2, one cargo of IPO5, and further confirmed that IPO5 bound to the NLS sequence of RASAL2, mediating RASAL2 nuclear translocation and inducing RAS signal activation, thereby promoting the progression of CRC. CONCLUSIONS: Together, our results indicate that IPO5 is overexpressed in colorectal cancer cells. By transporting RASAL2, IPO5 may play a crucial role in CRC.

16.
Am J Cancer Res ; 9(5): 1061-1073, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31218112

RESUMO

Slingshot phosphatase 3 (SSH3) is a member of the SSH phosphatase family that regulates actin filament dynamics. However, its role in cancer metastasis is relatively unclear compared to that of SSH1. Here, we showed that SSH3 was upregulated in colorectal cancer (CRC). Of note, SSH3 was upregulated in the tumor thrombus and lymph node metastasis compared with that in paired primary CRC tissues. High SSH3 expression was associated with the aggressive phenotype of CRC and may be an independent prognostic factor for the poor survival of patients with CRC. SSH3 significantly enhanced the invasion and metastasis of CRC cells in vitro and in vivo. Moreover, SSH3 regulated the remodeling of actin, which is involved in the cytoskeleton signaling pathway, through its interaction with LIMK1/Rac1 and subsequently promoted CRC cell invasion and metastasis. Our data elucidate an important role for SSH3 in the progression of CRC, and SSH3 may be considered a potential therapeutic target for CRC.

17.
Oncol Lett ; 17(6): 4907-4913, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31186699

RESUMO

Clear cell renal cell carcinoma (ccRCC) is one of the most common types of kidney cancer and is accompanied by a poor prognosis due to a high potential for metastasis and recurrence. The mechanism of ccRCC metastasis is not well known. N-lysine methyltransferase KMT5A serves a crucial role in the progression of human cancer; however, the function of KMT5A in the development of ccRCCs has not yet been investigated, which has triggered an interest in investigating the potential association between KMT5A and ccRCC. The present study demonstrates for the first time that KMT5A is a driving factor in ccRCC metastasis. The KMT5A expression level was revealed to be significantly higher in ccRCC tissues compared with adjacent normal tissues. Patients with ccRCC whose tumors expressed high levels of KMT5A were demonstrated to have significantly shorter postoperative survival times. In vitro knockdown of KMT5A expression in 786-O cells inhibited cell migration and invasion. KMT5A reduced cadherin-1 (CDH1) protein levels by directly inhibiting its transcription. The CDH1 mRNA levels were inversely correlated with KMT5A expression in ccRCC samples. Patients with high tumor KMT5A or low CDH1 levels had the poorest prognosis with the shortest overall survival (OS) time, and this combination was demonstrated to be an independent prognostic indicator for patient OS time in ccRCC, more accurate than monitoring KMT5A or CDH1 alone. Together, these results indicate that KMT5A serves a vital role in ccRCC development and progression, and it may be a novel target for ccRCC treatment and prevention.

18.
Materials (Basel) ; 12(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939769

RESUMO

The warm and ice-rich frozen soil (WIRFS) that underlies roadway embankments in permafrost regions exhibit large compression and thaw deformation, which can trigger a series of distresses. Cement and additives were used in this study to improve the compressibility and thaw-settlement properties of WIRFS. We, therefore, selected optimum additives and studied the improvement effect on the frozen soil with 30% water content based on our previous research. Given constant load and variable temperatures, compression coefficients, thaw strains, and water content changes were obtained at temperatures of -1.0 °C, -0.5 °C, and 2.0 °C to evaluate the effect of improvements. A scanning electron microscope (SEM) was then used to observe the microstructure of improved soils and analyze causal mechanisms. Data show that hydration reactions, physical absorptions, cement, and additives formed new structures and changed the phase of water in frozen soil after curing at -1.0 °C for 28 days. This new structure, cemented with soil particles, unfrozen water, and ice, filled in the voids of frozen soil and effectively decreased the WIRFS compression coefficient and thaw strain.

19.
Artigo em Inglês | MEDLINE | ID: mdl-30887309

RESUMO

The effects of fructose on plantaricin Q7 biosynthesis in Lactobacillus plantarum (L. plantarum) Q7 were investigated. Fructose induced and accelerated plantaricin Q7 production in the early stages of biosynthesis. Two-dimensional electrophoresis and quantitative real-time reverse transcriptase PCR (qRT-PCR) revealed that shock-related proteins were overexpressed in L. plantarum grown in MRS-fructose compared with cultures grown in MRS broth. A preheat-shock (PHS) treatment was used to overexpress shock-related proteins to enhance plantaricin Q7 production. The final plantaricin Q7 level reached 2873.08 IU/mL following PHS treatment, which was 23.36% higher than that obtained using a control strategy without PHS treatment. qRT-PCR analyses indicated that only groL was induced (by 10-fold) following PHS treatment. Evidently, groL plays a critical role in plantaricin Q7 biosynthesis. These results demonstrate that PHS treatment is an efficient approach to improving plantaricin Q7 production. The information obtained in this study may increase the amount of efficient antimicrobial peptide production using L. plantarum.

20.
Carbohydr Polym ; 211: 118-123, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824071

RESUMO

TEMPO-mediated oxidation has been successfully used to prepare carboxylated chitin nanofibers (ChNFs) with purified chitins originating from the outer shells of crab and shrimp (α-form) or tubeworm (ß-form). However, the method for obtaining carboxylated ChNFs with squid pen chitin (hydrated ß-form) has not been developed yet. It might be due to the existence of the small amount of partial deacetylation (DD ≈ 9%) in the squid pen ß-chitins. Herein, ultrafine (2-4 nm in width and several micrometers in length) and carboxylated ß-ChNFs were fabricated directly from the squid pen with simultaneously removing of protein, CaCO3 and other non-chitin components by one-step oxidation procedure using ammonium persulfate (APS) and followed ultrasonic disintegration under acid conditions. When 45 wt% APS was used to react with squid pen, the carboxylate content of ChNFs reaches 0.802 mmol/g. Therefore, the ß-ChNFs with anionically charged groups (COO-) can be dispersed stably in aqueous solution under basic conditions. Meanwhile, thus-obtained ß-ChNFs aqueous solution even with very low concentration (0.8%) can be transformed to transparent, robust and moldable hydrogels by gas coagulation of acetic acid.

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