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1.
Med Image Anal ; 59: 101572, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31639622

RESUMO

Surgical tool presence detection and surgical phase recognition are two fundamental yet challenging tasks in surgical video analysis as well as very essential components in various applications in modern operating rooms. While these two analysis tasks are highly correlated in clinical practice as the surgical process is typically well-defined, most previous methods tackled them separately, without making full use of their relatedness. In this paper, we present a novel method by developing a multi-task recurrent convolutional network with correlation loss (MTRCNet-CL) to exploit their relatedness to simultaneously boost the performance of both tasks. Specifically, our proposed MTRCNet-CL model has an end-to-end architecture with two branches, which share earlier feature encoders to extract general visual features while holding respective higher layers targeting for specific tasks. Given that temporal information is crucial for phase recognition, long-short term memory (LSTM) is explored to model the sequential dependencies in the phase recognition branch. More importantly, a novel and effective correlation loss is designed to model the relatedness between tool presence and phase identification of each video frame, by minimizing the divergence of predictions from the two branches. Mutually leveraging both low-level feature sharing and high-level prediction correlating, our MTRCNet-CL method can encourage the interactions between the two tasks to a large extent, and hence can bring about benefits to each other. Extensive experiments on a large surgical video dataset (Cholec80) demonstrate outstanding performance of our proposed method, consistently exceeding the state-of-the-art methods by a large margin, e.g., 89.1% v.s. 81.0% for the mAP in tool presence detection and 87.4% v.s. 84.5% for F1 score in phase recognition.

2.
J Cell Physiol ; 235(2): 1025-1035, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31240705

RESUMO

Cutaneous malignant melanoma (hereafter called melanoma) is one of the most aggressive cancers with increasing incidence and mortality rates worldwide. In this study, we performed a systematic investigation of the tumor microenvironmental and genetic factors associated with melanoma to identify prognostic biomarkers for melanoma. We calculated the immune and stromal scores of melanoma patients from the Cancer Genome Atlas (TCGA) using the ESTIMATE algorithm and found that they were closely associated with patients' prognosis. Then the differentially expressed genes were obtained based on the immune and stromal scores, and prognostic immune-related genes further identified. Functional analysis and the protein-protein interaction network further revealed that these genes enriched in many immune-related biological processes. In addition, the abundance of six infiltrating immune cells was analyzed using prognostic immune-related genes by TIMER algorithm. The unsupervised clustering analysis using immune-cell proportions revealed eight clusters with distinct survival patterns, suggesting that dendritic cells were most abundant in the microenvironment and CD8+ T cells and neutrophils were significantly related to patients' prognosis. Finally, we validated these genes in three independent cohorts from the Gene Expression Omnibus database. In conclusion, this study comprehensively analyzed the tumor microenvironment and identified prognostic immune-related biomarkers for melanoma.

3.
Nanotechnology ; 31(4): 045202, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31557740

RESUMO

Spin transfer nano-oscillators (STNOs) are a new type of radio frequency (RF) oscillators that utilize the current-induced magnetization precession in a magnetic tunnel junction device to generate high frequency microwave signal. Since both the frequency and the amplitude of STNOs can be tuned by changing the current, they are potentially used for amplitude shift keying and frequency shift keying modulation without the need for an RF mixer, which leads to compact RF components. In this letter, a novel strategy is proposed to modulate the frequency and the amplitude by memristor-controlled spin nano-oscillators, whereby the STNO is responsible for microwave emitting and memristor serves as a current regulator which further modulates the frequency and amplitude. In addition, the I-V curves show that a multilevel resistance behavior can also be achieved in the same architecture.

4.
Phytochemistry ; 169: 112184, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31678787

RESUMO

An extensive phytochemical investigation on the chemical constituents from the needles and twigs of the vulnerable conifer Pseudotsuga sinensis yielded 19 diterpenoids and 21 sesquiterpenoids with various carbocyclic skeletons. Among them, 13 (named pseudosinins A-M, resp.) were undescribed compounds. Their structures with absolute configurations were characterized by a combination of spectroscopic methods, calculated and experimental electronic circular dichroism (ECD) data, quantum chemical calculations of the chemical shifts, and single crystal X-ray diffraction analyses. In particular, an array of labdane-derived norditerpenoids with C19-, C18-, and C16-skeletons, and related drimane-type sesquitepenoids with C15- and C13-skeletons were found in the title plant. The possible biogenetic relationships of these degraded terpenoids were briefly discussed. Among the isolates, pseudosinin D, cis-communic acid, and 4ß,15-dihydroxy-19-norabieta-8,11,13-trien-7-one showed moderate inhibitory activities against the enzyme ATP-citrate lyase (ACL), a potential drug target for the treatment of hyperlipidemia and hypercholesterolemia.

5.
Plant Physiol ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712306

RESUMO

Terpenes are specialized metabolites ubiquitously produced by plants via the action of terpene synthases (TPSs). There are enormous variations in the types and amounts of terpenes produced by individual species. To understand the mechanisms responsible for such vast diversity, here we investigated the origin and evolution of a cluster of tandemly arrayed TPS genes in Oryza. In the Oryza species analyzed, TPS genes occur as a three-TPS cluster, a two-TPS cluster, and a single TPS gene in five, one, and one species, respectively. Phylogenetic analysis inferred the origins of the two-TPS and three-TPS clusters and the role of species-specific losses of TPS genes. Within the three-TPS clusters, one orthologous group exhibited conserved catalytic activities. The other two groups, both of which contained pseudogenes and/or nonfunctional genes, exhibited distinct profiles of terpene products. Sequence and structural analysis combined with functional validation identified several amino acids in the active site that are critical for catalytic activity divergence of the three orthologous groups. In the five Oryza species containing the three-TPS cluster, their functional TPS genes showed both conserved and species-specific expression patterns in insect-damaged and untreated plants. Emission patterns of volatile terpenes from each species were largely consistent with the expression of their respective TPS genes and the catalytic activities of the encoded enzymes. This study indicates the importance of combinatorial evolution of TPS genes in determining terpene variations among individual species, which includes gene duplication, retention/loss/degradation of duplicated genes, varying selection pressure, retention/divergence in catalytic activities, and divergence in expression regulation.

6.
Bioengineered ; 10(1): 635-645, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31680623

RESUMO

Melanoma is a potentially fatal form of skin cancer with great metastatic potential. THOC2 plays a vital role in human biological progression, however, the roles of THOC2 in melanoma tumorigenesis are still unknown. In the present study, our data demonstrated that THOC2 expression was significantly increased in melanoma tissues, and high THOC2 expression was associated with poor overall survival of melanoma patients. THOC2 reduction repressed melanoma cell proliferation and invasion, and induced cell apoptosis in vitro. Microarray data revealed that the cAMP signaling pathway was significantly downregulated in A375 cells transfected with si-THOC2, which was further confirmed by RT-qPCR and bioinformatics analysis. In conclusion, our data indicated that THOC2 might act as an oncogene in melanoma progression through cAMP signaling pathway regulation, which may offer a therapeutic target for melanoma treatment.

7.
Medicine (Baltimore) ; 98(44): e17821, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689868

RESUMO

Although many genetic variants related to anti-tuberculosis drug induced liver injury (ATDILI) have been identified, the prediction and personalized treatment of ATDILI have failed to achieve, indicating there remains an area for further exploration. This study aimed to explore the influence of single nucleotide polymorphisms (SNPs) in Bradykinin receptor B2 (BDKRB2), Teneurin transmembrane protein 2 (TENM2), transforming growth factor beta 2 (TGFB2), and solute carrier family 2 member 13 (SLC2A13) on the risk of ATDILI.The subjects comprised 746 Chinese tuberculosis (TB) patients. Custom-by-design 2x48-Plex SNPscanTM kit was employed to genotype 28 selected SNPs. The associations of SNPs with ATDILI risk and clinical phenotypes were analyzed according to the distributions of allelic and genotypic frequencies and different genetic models. The odds ratio (OR) with corresponding 95% confidence interval (CI) was calculated.Among subjects with successfully genotyped, 107 participants suffered from ATDILI during follow-up. In BDKRB2, patients with rs79280755 G allele or rs117806152 C allele were more vulnerable to ATDILI (PBonferronicorrection = .002 and .03, respectively). Rs79280755 increased the risk of ATDILI significantly whether in additive (OR = 3.218, 95% CI: 1.686-6.139, PBonferroni correction = .003) or dominant model (PBonferroni correction = .003), as well as rs117806152 (Additive model: PBonferroni correction = .05; dominant model: PBonferroni correction = .03). For TENM2, rs80003210 G allele contributed to the decreased risk of ATDILI (PBonferroni correction = .02), while rs2617972 A allele conferred susceptibility to ATDILI (PBonferroni correction = .01). Regarding rs2617972, significant findings were also observed in both additive (OR = 3.203, 95% CI: 1.487-6.896, PBonferroni correction = .02) and dominant model (PBonferroni correction = .02). Moreover, rs79280755 and rs117806152 in BDKRB2 significantly affected some laboratory indicators. However, no meaningful SNPs were observed in TGFB2 and SLC2A13.Our study revealed that both BDKRB2 and TENM2 genetic polymorphisms were interrogated in relation to ATDILI susceptibility and some laboratory indicators in the Western Chinese Han population, shedding a new light on exploring novel biomarkers and targets for ATDILI.


Assuntos
Antituberculosos/efeitos adversos , Sinalização do Cálcio/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Receptor B2 da Bradicinina/genética , Adulto , Grupo com Ancestrais do Continente Asiático/genética , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Proteínas Facilitadoras de Transporte de Glucose/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fator de Crescimento Transformador beta2/genética
8.
G3 (Bethesda) ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722887

RESUMO

The ladybird beetle Serangium japonicum is an important predator of whiteflies. Investigations of the molecular mechanisms of this predatory beetle have been hindered by the scarcity of gene sequence data. To obtain gene sequences for the ladybird beetle and determine differences in gene expression between the summer and winter seasons, paired-end sequencing was performed. Real-time PCR was used to validate differences in Krueppel homolog 1 gene (Kr-h1) mRNA expression in summer versus winter samples. To determined the diversity of the population, annotated cytochrome c oxidase subunit I gene (COX1) gene fragments were amplified from several ladybird beetle populations. The analysis yielded 191,246 assembled unigenes, 127,016 of which (66.4%) were annotated. These functional annotations of gene sequences are currently available from the National Center for Biotechnology Information (NCBI), and will provide a basis for studying the molecular mechanisms underlying the biological characteristics of S. japonicum We found a change in expression of ribosome-associated genes across seasons, and postulate that this change is because of seasonal variation in temperature and photoperiod. The differential expression of Kr-h1 suggests that S. japonicum can successfully overwinter because the adults enter diapause. To explain the effects of season on Kr-h1 gene expression, we hypothesize a model in which that a short photoperiod affects the density of Ca2+, the subsequent activity of methyl farnesoate epoxidase and the synthesis of JH, and in turn Kr-h1 gene expression. COX1 annotation was concordant with the morphological ID. The same COX1 sequence was found in the samples from several provinces in China. Therefore, the COX1 sequence is worth further study to distinguish beetle species and populations.

9.
J Cell Biochem ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724220

RESUMO

There is increasing evidence has indicated that long non-coding RNAs (lncRNAs) are implicated in the tumorigenesis and development of colorectal cancer (CRC). Nevertheless, the clinical significances and functions of FENDRR in CRC remain unknown. In this study, we reveal that lncRNA FENDRR is downregulated in CRC and negatively correlated with advanced stage and poor clinical outcomes of patient with CRC. Overexpression of FENDRR represses the proliferation, migrate and invasive capacities of CRC cell in vitro, and upregulation of FENDRR inhibits the growth and distant metastatic capacity of CRC cell in vivo. Mechanistically, FENDRR interacts with miRNA-18a-5p (miR-18a-5p) and subsequently regulates the expression of inhibitor of growth 4 (ING4) in CRC cell. Interestingly, ING4 repression or miR-18a-5p rescues FENDRR induced proliferation and aggressive phenotypes inhibition of CRC cell. Altogether, our findings suggest that FENDRR exerts an inhibitory role in CRC by interacting with miR-18a-5p and future increases ING4 expression.

10.
Molecules ; 24(21)2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31689885

RESUMO

The effect of Rhodiola sachalinensis Boriss extract irradiated with 50 kGy gamma rays (HKC) on benign prostatic hyperplasia (BPH) was investigated. Seven-week-old male SD rats received a subcutaneous injection of 20 mg/kg of testosterone propionate (TP) to induce BPH. Then, the testosterone only group received testosterone, the testosterone + finasteride group received testosterone and finasteride (5 mg/kg), the testosterone + HKC group received testosterone and HKC extract (500 mg/kg). Prostate weight and the dihydrotestosterone (DHT) levels in serum or prostate tissue were determined. The mRNA expressions of 5-alpha reductase (AR) in prostate tissue were also measured. Compared to the control group, prostate weight was significantly improved in the TP group and decreased in the HKC and finasteride-treated groups. Furthermore, the mRNA expression of 5-AR in the prostate was significantly reduced in the HKC and finasteride-treated groups. Similarly, the expression levels of α-smooth muscle actin (α-SMA) and cytokeratin, which are associated with prostatic enlargement in the HKC and finasteride groups, were much lower than in the TP group. HKC treatment showed similar efficacy to finasteride treatment on rats with testosterone-induced BPH. HKC may be explored as a potential new drug for BPH treatment.

12.
Biomed Pharmacother ; 121: 109355, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683179

RESUMO

Pancreatic cancer is one of the most severe types of tumors, with a 5-year survival rate of less than 7%. The prognosis and treatment of pancreatic cancer are largely limited by the extent of tumor invasion and the presence of lymph node and distant metastases. Therefore, exploring the biological behavior of pancreatic cancer cells (PCCs) is extremely important for the understanding, diagnosis, and treatment of pancreatic cancer. Current studies have shown that pancreatic stellate cells (PSCs) regulate the biological behavior of PCCs, such as their proliferation, apoptosis, invasion, and migration, by remodeling the extracellular matrix. Though Hic-5 is an important gene in PSCs, no study has investigated the regulation of PCCs by Hic-5. Here, we demonstrate that Hic-5 expression is upregulated in pancreatic cancer and that siRNA transfection can effectively inhibit Hic-5 expression. Compared to the control group, Hic-5 inhibition significantly reduced proliferation, increased apoptosis, and reduced invasion and migration of PCCs. Moreover, the inhibition of Hic-5 expression simultaneously reduced matrix metalloproteinase-9 (MMP-9) expression. Statistical analysis revealed that Hic-5 expression was higher among the pancreatic cancer group than among the normal group and was negatively correlated with postoperative survival time among patients with pancreatic cancer. These results have important clinical significance for further exploring the molecular mechanism involved in Hic-5-mediated invasion and metastasis of pancreatic cancer and ameliorating the prognosis of patients with pancreatic cancer.

13.
Transbound Emerg Dis ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705830

RESUMO

A highly acute disease broke out in ducklings in Shandong Province in March 2019. The disease was characterized as visceral gout, with a mortality rate of 30%. The causative agent, which has given rise to similar symptoms in goslings, has been confirmed to be a novel goose astrovirus. The novel goose astrovirus, which was designated as the SDXT strain, was identified from a diseased duck farm using duck embryo primary cells in an experimental infection test. Genomic sequence analysis, as well as phylogenetic analysis of the viral proteins, revealed that the SDXT strain was closely related to a novel goose astrovirus of the Avastrovirus 3 species. These results indicate that the novel goose astrovirus may cross-host infect ducklings. Further studies are needed to define its host range and transmission route.

14.
Mikrochim Acta ; 186(12): 789, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732798

RESUMO

A corn-like CeO2/C coaxial cable textured by a cerium oxide shell and a carbon core was designed to sense NO. The carbon core possesses high electrical conductivity, and the CeO2 surface delivers excellent electrocatalytic activity. The sensor, typically operated at 0.8 V (vs. Ag/AgCl), exhibits a detection limit of 1.7 nM, which is 4-times lower than that of CeO2 nanotubes based one (at S/N = 3). It also displays wide linear response (up to 83 µM), a sensitivity of 0.81 µA µM-1 cm-2, and fast response (2 s). These values are highly competitive to that of a CeO2 tube (0.92 µA µM-1 cm-2 and 2 s). The sensor was used to quantify NO that is released by Aspergillus flavus. Graphical abstractSchematic representation of corn-like CeO2/C which can more sensitively and effectively detect NO released from A. flavus than when using CeO2 nanotubes, benefitting from its unique coaxial cable structure.

15.
ACS Chem Biol ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31714738

RESUMO

Because of its multifaceted role in cellular functions, tubulin is a validated and productive drug target for cancer therapy. While many tubulin inhibitors demonstrate clinical efficacy, they are often limited by the development of multidrug resistance. Therefore, implementation of tubulin inhibitors that can overcome resistance could provide significant therapeutic benefits. To optimize our previously reported tubulin inhibitor, 4a, we designed and synthesized two new analogues, SB202 and SB204, based on the crystal structure of 4a in complex with tubulin protein. SB202 and SB204 achieved enhanced binding at the colchicine site in tubulin and also showed improved metabolic stability and antiproliferative potency in vitro. Functional studies confirmed that SB202 and SB204 inhibit tubulin polymerization, arrest cells in the G2/M phase of the cell cycle, interfere with cancer cell migration and proliferation, and enhance apoptotic cascades. When evaluated in vivo, SB202 exhibited antitumor and vascular disrupting action against paclitaxel-resistant mouse xenograft models, strongly suggesting the potential of this scaffold to overcome multidrug resistance for cancer therapy.

16.
Cell Rep ; 29(7): 2001-2015.e5, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31722213

RESUMO

Compensation among paralogous transcription factors (TFs) confers genetic robustness of cellular processes, but how TFs dynamically respond to paralog depletion on a genome-wide scale in vivo remains incompletely understood. Using single and double conditional knockout of myocyte enhancer factor 2 (MEF2) family TFs in granule neurons of the mouse cerebellum, we find that MEF2A and MEF2D play functionally redundant roles in cerebellar-dependent motor learning. Although both TFs are highly expressed in granule neurons, transcriptomic analyses show MEF2D is the predominant genomic regulator of gene expression in vivo. Strikingly, genome-wide occupancy analyses reveal upon depletion of MEF2D, MEF2A occupancy robustly increases at a subset of sites normally bound to MEF2D. Importantly, sites experiencing compensatory MEF2A occupancy are concentrated within open chromatin and undergo functional compensation for genomic activation and gene expression. Finally, motor activity induces a switch from non-compensatory to compensatory MEF2-dependent gene regulation. These studies uncover genome-wide functional interdependency between paralogous TFs in the brain.

17.
Soft Matter ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746924

RESUMO

The strategy of dual cross-linking was investigated by enhancing the performance of dynamic hydrogels. To this end, phenylalanine modified ε-polylysine was synthesized and employed as the polymer backbone of hydrogels. The phenylalanine moieties and amine groups of the polymer could be cross-linked with cucurbit[8]uril (CB[8]) and the dialdehyde cross-linker, respectively. Single CB[8] linkage with fast dynamics led to an increase in the viscosity of the polymer solution, and single imine linkage with slow dynamics led to the formation of weak and brittle hydrogels. However, the two linkages were combined together to form a dual-cross-linked hydrogel and the performance of the hydrogel could be well enhanced. Compared with the single imine cross-linked hydrogel, the dual-cross-linked hydrogel demonstrated a higher mechanical strength, better extensibility and faster self-healing rate. It is anticipated that this line of research could provide a useful method to enhance the performance of dynamic hydrogels.

18.
Chaos ; 29(10): 103148, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31675794

RESUMO

It has been demonstrated that the presence of chaos may lead to greater entanglement generation for some physical systems. Here, we find different effects of chaos on the spin-motion entanglement for a two-frequency driven Bose-Einstein condensate with spin-orbit coupling. We analytically and numerically demonstrate that classical chaos can assist or suppress entanglement generation, depending on the initial phase differences between two motional states, which can be manipulated by using the known phase-engineering method. The results could be significant in engineering nonlinear dynamics for quantum information processing with many-body entanglement.

19.
Int J Artif Organs ; : 391398819882697, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31665956

RESUMO

OBJECTIVE: This study aims to evaluate the effectiveness of individualized hemodialysis for unconventional hypotension in diabetic nephropathy patients. METHODS: A total of 60 patients were selected and randomly divided into study group and control group. The control group used the standard dialysis model, while the study group used the individualized hemodialysis scheme, in which the dialysis was performed using an individualized dialysis machine temperature control, pattern of natrium, and pattern of step ultrafiltration in combination with dialysate-containing glucose. RESULTS: The total occurrence rate of hypotension, dry weight standard-reaching rate, and blood quality during and after dialysis in the study group were superior to those in the control group (P < 0.05). Furthermore, the symptom scores in the study group (dizziness score, chest distress score, sweating score, muscle spasm score, gastrointestinal symptom score, and temporary mind change score) were lower than those in the control group (P < 0.05). The serum sodium, potassium, and chloride concentration in these two groups after dialysis was not statistically different (P > 0.05). CONCLUSION: The combined application of low temperature, pattern of natrium, pattern of step ultrafiltration, and dialysate-containing glucose individualization is safe and effective for preventing and controlling the occurrence of intradialytic hypotension (IDH), improve symptoms, and improve the dry weight standard-reaching rate.

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