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1.
Carbohydr Polym ; 230: 115618, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887924

RESUMO

Cellulose nanocrystals (CNC) show great potential in polymers due to their sustainability and excellent mechanical properties, etc. Herein, we used CNC as sustainable additive to improve mechanical and shape memory properties of polylactide (PLA)/epoxidized natural rubber (ENR) thermoplastic vulcanizates (TPVs). A method of combining latex mixing and melt mixing was used to achieve homogeneous dispersion of CNC. With only 5 phr (relative to ENR) CNC, tensile strength, Young's modulus and dynamic storage modulus at 20 ℃ increased by 22 %, 64 % and 78 % compared with unfilled sample. The shape recovery behavior also improved with the incorporation of CNC, which increased from 87.4 % of unfilled TPV to 91.7 % of sample with 5 phr CNC. Moreover, the decline of Rr in the subsequent cycles also reduced with incorporation of CNC. These results indicate that the enhanced cross-linked rubber network and increased crystallinity of PLA contributed to the enhanced properties.

2.
BMC Genomics ; 21(1): 4, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898486

RESUMO

BACKGROUND: Somatic embryogenesis (SE) is a process of somatic cells that dedifferentiate to totipotent embryonic stem cells and generate embryos in vitro. Longan SE has been established and wildly used as model system for studying embryogenesis in woody plants, SE-related genes had been characterized. In spite of that, a comprehensive overview of SE at a molecular level is still absent. To understand the molecular mechanisms during longan SE, we examined the transcriptome changes by using Illumina HiSeq from the four distinct developmental stages, including non-embryogenic callus (NEC), embryogenic callus (EC), incomplete compact pro-embryogenic cultures (ICpEC), globular embryos (GE). RESULTS: RNA-seq of the four samples generated a total of 243.78 million high quality reads, approximately 81.5% of the data were mapped to longan genome. The cDNA libraries of NEC, EC, ICpEC and GE, generated 22,743, 19,745, 21,144, 21,102 expressed transcripts, 1935, 1710, 1816, 1732 novel transcripts, 2645, 366, 505, 588 unique genes, respectively. Comparative transcriptome analysis showed that a total of 10,642, 4180, 5846 and 1785 genes were differentially expressed in the pairwise comparisons of NEC_vs_EC, EC_vs_ICpEC, EC_vs_GE, ICpEC_vs_GE, respectively. Among them, plant hormones signalling related genes were significantly enriched, especially the auxin and cytokinin signalling components. The transcripts of flavonoid biosynthesis related genes were mainly expressed in NEC, while fatty acid biosynthesis related genes mainly accumulated in early SE. In addition, the extracelluar protein encoding genes LTP, CHI, GLP, AGP, EP1 were related to longan SE. Combined with the FPKM value of longan nine tissues transcription, 27 SE specific or preferential genes (LEC1, LEC1-like, PDF1.3, GH3.6, AGL80, PIN1, BBM, WOX9, WOX2, ABI3, et al.) and 28 NEC preferential genes (LEA5, CNOT3, DC2.15, PR1-1, NsLTP2, DIR1, PIP1, PIP2.1, TIP2-1, POD-P7 and POD5 et al.) were characterized as molecular markers for longan early SE. qRT-PCR validation of SE-related genes showed a high correlation between RNA-seq and qRT-PCR data. CONCLUSION: This study provides new insights into the role of the transcriptome during early SE in longan. Differentially expressed genes reveal that plant hormones signalling, flavonoid and fatty acid biosynthesis, and extracelluar protein related genes were involved in longan early SE. It could serve as a valuable platform resource for further functional studies addressing embryogenesis in woody plants.

3.
Abdom Radiol (NY) ; 45(2): 332-341, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31642964

RESUMO

PURPOSE: To investigate the usefulness of b value threshold (bThreshold) map in the evaluation of rectal adenocarcinoma by comparing it with diffusion-weighted images and ADC maps regarding lesion detection and the prediction of pathological features. MATERIALS AND METHODS: Thirty-five patients with rectal tumors were enrolled and underwent axial DWI using a 3-Tesla MRI system. Contrast-to-noise ratio (CNR) between the lesions and normal tissues were assessed on the diffusion-weighted images and bThreshold maps. Reproducibility for ADC and bThreshold values were assessed. Significant differences between different groups for pathological prognostic factors were evaluated. Diagnostic performance of ADC and bThreshold values for those factors were assessed. RESULTS: Reproducibility was excellent for the ADC and bThreshold values (ICC 0.985 and 0.992; CV 3.8% and 4.0%) measurements. The CNR between lesions and normal tissues on bThreshold maps was significantly higher than that on diffusion-weighted images (9.91 ± 5.35 vs. 7.68 ± 3.08, p = 0.012). There were significant differences in the ADC and bThreshold values between different pathologic differentiation degrees and T stages; significant difference was observed in the bThreshold values between the different N stage groups (all p values < 0.050). No significant differences were observed between the ROC curves of ADC and the bThreshold values of rectal lesions for pathologic differentiation and T stage. bThreshold maps showed good diagnostic performance for N stage. CONCLUSION: Both ADC and bThreshold values can differentiate between degrees of pathologic differentiation and T1-2 versus T3-4. Potential added advantages however of the bThreshold map include a higher CNR compared with DWI images, thereby improving lesion visualization detection, and better diagnostic performance for end staging than ADC. Thus, the bThreshold map may compliment DWI and ADC to evaluate pathologic features of rectal primary tumors and metastatic lymph nodes.

4.
Chemosphere ; 238: 124594, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31445334

RESUMO

Enhancing the biodegradation efficiency of atrazine, a kind of commonly applied herbicide, has been attracted much more concern. Here, Zn2+ which has long been considered essential in adjusting cell physiological status was selected to investigate its role on the biodegradation of atrazine by Arthrobacter sp. DNS10 as well as the transmembrane transport of atrazine during the biodegradation period. The results of gas chromatography showed that the atrazine removal percentages (initial concentration was 100 mg L-1) in 0.05 mM Zn2+ and 1.0 mM Zn2+ treatments were 94.42% and 86.02% respectively at 48 h, while there was also 66.43% of atrazine left in the treatment without exogenous Zn2+ existence. The expression of atrazine chlorohydrolase gene trzN in the strain DNS10 cultured with 0.05 mM and 1.0 mM Zn2+ was 7.30- and 4.67- times respectively compared with that of the non-zinc treatment. In addition, the flow cytometry test suggests that 0.05 mM of Zn2+ could better adjust the membrane permeability of strain DNS10, meanwhile, the amount of atrazine accumulation in the strain DNS10 co-cultured with this level Zn2+ was 2.21 times of that of the strain without Zn2+. This study may facilitate a better understanding of the mechanisms that exogenous Zn2+ enhances the biodegradation of atrazine by Arthrobacter sp. DNS10.


Assuntos
Arthrobacter/metabolismo , Atrazina/análise , Herbicidas/análise , Hidrolases/biossíntese , Zinco/farmacologia , Biodegradação Ambiental/efeitos dos fármacos , Transporte Biológico/fisiologia , Hidrolases/genética , Permeabilidade/efeitos dos fármacos , Microbiologia do Solo
5.
Cancer Imaging ; 19(1): 83, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801587

RESUMO

BACKGROUND: To investigate and compare the diagnostic performance in T staging for patients with esophagogastric junction cancer using high-resolution magnetic resonance imaging (HR MRI), as compared with conventional MRI at 3 Tesla. METHODS: A total of 118 patients with pathologically confirmed esophagogastric junction cancer were included and underwent multiparameter HR MRI (Cohort 1, 62 patients) or conventional MRI (Cohort 2, 56 patients). T2-weighted, T1-weighted, diffusion-weighted and contrast-enhanced T1-weighted images of each patient were evaluated by two radiologists who determined the preoperative T staging by consensus. Using pathologic staging as the gold standard, the consistency between HR MRI and pathology and between conventional MRI and pathology in T staging was calculated and compared. The overall accuracy, overstatement and understatement of HR MRI and conventional MRI in T staging of patients with esophagogastric junction cancer were computed and compared. Moreover, the diagnostic performance of HR MRI and conventional MRI in T staging (≤ T1 and ≥ T4) of patients with esophagogastric junction cancer were evaluated. RESULTS: There were no significant differences in age (p = 0.465) and sex (p = 0.175) between Cohorts 1 and 2. Excellent agreement was observed in the T staging of patients with esophagogastric junction cancer between pathology and HR MRI (kappa = 0.813), while moderate agreement was observed between pathology and conventional MRI (kappa = 0.486). Significant differences were observed in overall accuracy (88.7% vs 64.3%, p = 0.002) and understatement (1.6% vs 26.8%, p < 0.001) but not for overstatement (9.7% vs 8.9%, p = 0.889) in T staging between HR MRI and conventional MRI techniques. For differentiating the T stages of ≤ T1 from ≥ T2 and the T stages of ≤ T3 from ≥ T4, no significant differences were observed between the imaging techniques. CONCLUSIONS: HR MRI has good diagnostic performance and may serve as an alternative technique in the T staging of patients with esophagogastric junction cancer in clinical practice.

6.
PLoS One ; 14(10): e0223519, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644543

RESUMO

Gerbera hybrida is one of the top five cut flowers across the world, it is host for the root rot causing parasite called Phytophthora cryptogea. In this study, plantlets of healthy and root-rot pathogen-infected G. hybrida were used as plant materials for transcriptome analyis using high-throughput Illumina sequencing technique. A total 108,135 unigenes were generated with an average length of 727 nt and N50 equal to 1274 nt out of which 611 genes were identified as DEGs by DESeq analyses. Among DEGs, 228 genes were up-regulated and 383 were down-regulated. Through this annotated data and Kyoto encyclopedia of genes and genomes (KEGG), molecular interaction network, transcripts accompanying with tyrosine metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis, phenylpropanoid and flavonoid biosynthesis, and plant hormone signal transduction pathways were thoroughly observed considering expression pattern. The involvement of DEGs in tyrosine metabolism pathway was validated by real-time qPCR. We found that genes related with tyrosine metabolism were activated and up-regulated against stress response. The expression of GhTAT, GhAAT, GhHPD, GhHGD and GhFAH genes was significantly increased in the leaves and petioles at four and six dpi (days post inoculation) as compared with control. The study predicts the gene sequences responsible for the tyrosine metabolism pathway and its responses against root-rot resistance in gerbera plant. In future, identification of such genes is necessary for the better understanding of rot resistance mechanism and to develop a root rot resistance strategy for ornamental plants.

7.
J Am Med Inform Assoc ; 26(11): 1314-1322, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31294792

RESUMO

OBJECTIVE: Active Learning (AL) attempts to reduce annotation cost (ie, time) by selecting the most informative examples for annotation. Most approaches tacitly (and unrealistically) assume that the cost for annotating each sample is identical. This study introduces a cost-aware AL method, which simultaneously models both the annotation cost and the informativeness of the samples and evaluates both via simulation and user studies. MATERIALS AND METHODS: We designed a novel, cost-aware AL algorithm (Cost-CAUSE) for annotating clinical named entities; we first utilized lexical and syntactic features to estimate annotation cost, then we incorporated this cost measure into an existing AL algorithm. Using the 2010 i2b2/VA data set, we then conducted a simulation study comparing Cost-CAUSE with noncost-aware AL methods, and a user study comparing Cost-CAUSE with passive learning. RESULTS: Our cost model fit empirical annotation data well, and Cost-CAUSE increased the simulation area under the learning curve (ALC) scores by up to 5.6% and 4.9%, compared with random sampling and alternate AL methods. Moreover, in a user annotation task, Cost-CAUSE outperformed passive learning on the ALC score and reduced annotation time by 20.5%-30.2%. DISCUSSION: Although AL has proven effective in simulations, our user study shows that a real-world environment is far more complex. Other factors have a noticeable effect on the AL method, such as the annotation accuracy of users, the tiredness of users, and even the physical and mental condition of users. CONCLUSION: Cost-CAUSE saves significant annotation cost compared to random sampling.

8.
Artigo em Inglês | MEDLINE | ID: mdl-30946661

RESUMO

We propose a framework, named Aggregated Wasserstein, for computing a distance between two Hidden Markov Models with state conditional distributions being Gaussian. For such HMMs, the marginal distribution at any time position follows a Gaussian mixture distribution, a fact exploited to softly match, aka register, the states in two HMMs. The registration of states is inspired by the intrinsic relationship of optimal transport and the Wasserstein metric between distributions. Specifically, the components of the marginal GMMs are matched by solving an optimal transport problem where the cost between components is the Wasserstein metric for Gaussian distributions. The solution of the optimization problem is a fast approximation to the Wasserstein metric between two GMMs. The new Aggregated Wasserstein distance is a semi-metric and can be computed without generating Monte Carlo samples. It is invariant to permutation of states. This distance quantifies the dissimilarity of GMM-HMMs by measuring both the difference between the two marginal GMMs and that between the two transition matrices. Our new distance is tested on tasks of retrieval, classification, and t-SNE visualization of time series. Experiments on both synthetic and real data have demonstrated its advantages in terms of accuracy and efficiency in comparison with existing distances.

9.
J Craniofac Surg ; 30(6): e501-e503, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30921064

RESUMO

The authors report a 34-year-old female with hemifacial spasm who was identified as a candidate for microvascular decompression. Lateral spread response (LSR) was not recorded at first because of anatomical shift of neurovascular relationship after drainage of cerebrospinal fluid, but they reappeared only after a piece of shredded gelatin sponge was placed near the posteroinferior cerebellar artery to expand surgical field. As the authors removed the gelatin sponge, the LSRs disappeared instantly. Subsequently, the authors put some soft shredded Teflon between the offending vessel and brainstem. Since then the authors did not find LSRs anymore. Clinical follow-up had been carried out with a questionnaire from 1 week to 3 months postoperatively, and the patient was cured with no complications. This report presented that the gelatin sponge placed in an inappropriate position resulting in compression potentially leading to the opposite effect of treatment. Such kind of excessive operation could be avoided by electrophysiological monitoring.

10.
Int J Mol Sci ; 20(2)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30669555

RESUMO

Light is an important factor that affects the synthesis of functional metabolites in longan embryogenic calli (ECs). However, analysis of the effect of light on functional metabolites in longan ECs via RNA sequencing has rarely been reported and their light regulation network is unclear. The contents of various functional metabolites as well as the enzymatic activities of superoxide dismutase and peroxidase and the level of H2O2 in longan ECs were significantly higher under blue light treatment than under the other treatments (dark, white). In this study, we sequenced three mRNA libraries constructed from longan ECs subjected to different treatments. A total of 4463, 1639 and 1806 genes were differentially expressed in the dark versus blue (DB), dark versus white (DW) and white versus blue (WB) combinations, respectively. According to GO and KEGG analyses, most of the differentially expressed genes (DEGs) identified were involved in transmembrane transport, taurine and hypotaurine metabolism, calcium transport and so forth. Mapman analysis revealed that more DEGs were identified in each DB combination pathway than in DW combination pathways, indicating that blue light exerts a significantly stronger regulatory effect on longan EC metabolism than the other treatments. Based on previous research and transcriptome data mining, a blue light signaling network of genes that affect longan functional metabolites was constructed and HY5, PIF4 and MYC2 were shown to be the key regulatory genes in the network. The results of this study demonstrate that the expression levels of phase-specific genes vary with changes in longan EC functional metabolites.


Assuntos
Luz , Metabolômica , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/efeitos da radiação , Sapindaceae/fisiologia , Sapindaceae/efeitos da radiação , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Metabolômica/métodos , Anotação de Sequência Molecular , Análise de Sequência de RNA , Transdução de Sinais , Transcriptoma
11.
J Environ Manage ; 233: 553-560, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597348

RESUMO

The accumulation of atrazine in farmland is prone to cause phytotoxicity to kinds of sensitive crops, such as soybean. In addition, some kinds of agricultural solid wastes have long been considered as the important non-point pollution source. The aim of this experiment was to investigate the feasibility of removing atrazine from soil and alleviating the stress of atrazine on the growth of soybean by application a novel bio-organic fertilizer developed by agricultural solid wastes, such as cow manure organic fertilizer, biochar and poly-(γ-glutamic acid), as well as an atrazine-degrading strain Arthrobacter sp. DNS10. Sixteen potential bio-organic fertilizer formulations were designed by D-optimal mixture design of Design Expert software and atrazine-removal ability was selected to single out the optimal formulation. As a result, the optimal formulation of bio-organic fertilizer (named as DNBF10) was produced by the cow manure organic fertilizer 76.20%, biochar 4.46%, poly-(γ-glutamic acid) 8.63% (m/m) and the number of Arthrobacter sp. DNS10 with 0.91 × 108 CFU/g. The atrazine removal percentage of DNBF10 for the atrazine in soil with the initial atrazine concentration 15.26 ±â€¯0.49 mg/kg was 95.05% after 10 days' application with DNBF10 at the adding dosage of 5 mg/kg (relative to the dry weight of the soil). Furthermore, pot experiment results suggest that the growth of soybean seedlings in the soil (initial atrazine was 8.14 ±â€¯0.16 mg/kg) that adding both of DNBF10 (25%) and chemical fertilizer (75%) were better than those of the treatment only adding chemical fertilizer (100%) under the same nutrient addition level. All the results indicate that the application of DNBF10 was a new alternative to reuse the typical agricultural solid wastes, as well as to reduce the harm caused by residual atrazine to soybean.


Assuntos
Atrazina , Herbicidas , Poluentes do Solo , Animais , Bovinos , Feminino , Fertilizantes , Esterco , Solo
12.
World Neurosurg ; 122: 512-517, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30448569

RESUMO

BACKGROUND: Methamphetamine (MA) addiction is one of the most prevalent socioeconomic and health problems worldwide. In recent years, deep brain stimulation (DBS) has increasingly been used for the treatment of addiction. CASE DESCRIPTION: This study reports on 2 MA-dependent patients who received DBS of the nucleus accumbens (NAc). During the approximately 2-year follow-up period, one patient (A) remained abstinent and presented with positive emotional experiences, whereas the other (B) had no significant psychobehavioral changes during stimulation at low-to-moderate voltages and subsequently relapsed. Through coregistration of preoperative magnetic resonance imaging with postoperative computed tomography/magnetic resonance imaging, the DBS electrode of patient A was confirmed to be accurately implanted in the NAc, whereas one side of the electrode of patient B deviated from the target. CONCLUSIONS: These case reports demonstrate that NAc-DBS maybe a possible treatment option for MA addiction.


Assuntos
Encéfalo/cirurgia , Estimulação Encefálica Profunda , Metanfetamina/uso terapêutico , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/cirurgia , Adulto , Estimulação Encefálica Profunda/métodos , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
ACS Appl Mater Interfaces ; 10(48): 40996-41002, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30456940

RESUMO

We designed novel self-healing thermoplastic vulcanizates (TPVs), achieving excellent thermal/magnetic/light-triggered shape memory assisted self-healing behavior. Damage on polylactide (PLA)/epoxidized natural rubber (ENR)/Fe3O4 TPVs could be healed via three events synergistically: the shape memory effect of TPVs resulted in the physical contact of damaged surfaces; the desorption-absorption of ENR/Fe3O4-bound rubber promoted interdiffusion of ENR chains, leading to the self-healing of ENR phase; ENR was grafted onto PLA segments to assist PLA rearranging and entangling again to achieve the repair of TPVs. This self-healing TPV is reported for the first time and paves the way to design next-generation self-healing materials.

14.
BMC Genomics ; 19(1): 805, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400813

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) are involved in variable cleavage, transcriptional interference, regulation of DNA methylation and protein modification. However, the regulation of lncRNAs in plant somatic embryos remains unclear. The longan (Dimocarpus longan) somatic embryogenesis (SE) system is a good system for research on longan embryo development. RESULTS: In this study, 7643 lncRNAs obtained during early SE in D. longan were identified by high-throughput sequencing, among which 6005 lncRNAs were expressed. Of the expressed lncRNAs, 4790 were found in all samples and 160 were specifically expressed in embryogenic callus (EC), 154 in incomplete embryogenic compact structures (ICpECs), and 376 in globular embryos (GEs). We annotated the 6005 expressed lncRNAs, and 1404 lncRNAs belonged to 506 noncoding RNA (ncRNA) families and 4682 lncRNAs were predicted to target protein-coding genes. The target genes included 5051 cis-regulated target genes (5712 pairs) and 1605 trans-regulated target genes (3618 pairs). KEGG analysis revealed that most of the differentially expressed target genes (mRNAs) of the lncRNAs were enriched in the "plant-pathogen interaction" and "plant hormone signaling" pathways during early longan SE. Real-time quantitative PCR confirmed that 20 selected lncRNAs showed significant differences in expression and that five lncRNAs were related to auxin response factors. Compared with the FPKM expression trends, 16 lncRNA expression trends were the same in qPCR. In lncRNA-miRNA-mRNA relationship prediction, 40 lncRNAs were predicted to function as eTMs for 15 miRNAs and 7 lncRNAs were identified as potential miRNA precursors. In addition, we verified the lncRNA-miRNA-mRNA regulatory relationships by transient expression of miRNAs (miR172a, miR159a.1 and miR398a). CONCLUSION: Analyses of lncRNAs during early longan SE showed that differentially expressed lncRNAs were involved in expression regulation at each SE stage, and may form a regulatory network with miRNAs and mRNAs. These findings provide new insights into lncRNAs and lay a foundation for future functional analysis of lncRNAs during early longan SE.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genoma de Planta , RNA Longo não Codificante/genética , Sapindaceae/embriologia , Sapindaceae/genética , Biologia Computacional , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Técnicas de Embriogênese Somática de Plantas , Sementes/genética
15.
Cancer Imaging ; 18(1): 43, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442202

RESUMO

BACKGROUND: To explore the effect of b-value distributions on the repeatability and diagnostic performance of the ADC value in rectal cancer patients using multiple b-values and mono-exponential model diffusion-weighted imaging (DWI). METHODS: Thirty-two preoperative rectal cancer patients, without receiving neoadjuvant therapy, were scanned on a 3 Tesla magnetic resonance imaging scanner using DWI with 10 b-values ranging from 0 to 2000 s/mm2. The apparent diffusion coefficient (ADC) value was calculated using a mono-exponential model and 31 b-value combinations consisting of 2 to 10 b-values were explored. Regions of interest with the maximum cross-sectional tumour size were outlined on the ADC map by two independent observers. Intraclass correlation coefficients (ICC), coefficient of variation (CV), and Bland-Altman plots between the two observers were calculated and evaluated to determine repeatability. Areas under receiver operating characteristic curves (AUCs) were evaluated for rectal cancer characterization. Correlations between the mean ADC values and T stage were assessed using the Spearman correlation coefficient (ρ). α (= ICC + AUC + |ρ|- CV - |bias|) was defined and used to assess the optimal b-value distribution. RESULTS: Postoperative pathology tests revealed 4 patients with T1, 10 patients with T2, and 18 patients with T3 stages. There were no significant difference in age and sex between the two groups (T1-2 vs. T3). Excellent reproducibility was observed for ADC values between two observers with ICC and CV values ranging from 0.920 to 0.998, and 1.475 to 5.568%, respectively. The mean percent difference and ρ between the paired measurements was ranged from - 2.7 to 1.2% and from - 0.759 to - 0.407, respectively. The b-value combinations with the top three α values were b(0, 1000 s/mm2), b(500, 1500, 2000 s/mm2) and b(100, 1000, 1500 s/mm2) for α = 2.581, 2.571 and 2.569, respectively. CONCLUSIONS: The number of b-values and their distributions influenced the repeatability of the ADC values and their diagnostic performance. The optimal b-value combination was 0 and 1000 s/mm2 for DWI examination of rectal cancer patients.


Assuntos
Imagem de Difusão por Ressonância Magnética/normas , Neoplasias Retais/diagnóstico por imagem , Adulto , Idoso , Interpretação Estatística de Dados , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Reprodutibilidade dos Testes
16.
Int J Mol Sci ; 19(8)2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30110985

RESUMO

Mother of FT and TFL1 (MFT) belongs to phosphatidylethanolamine-binding protein (PEBP) family, which plays an important role in flowering time regulation, seed development, and germination. To gain insight into the molecular function of DlMFT in Dimocarpus longan Lour., we isolated DlMFT and its promoter sequence from longan embryogenic callus (EC). Bioinformatic analysis indicated that the promoter contained multiphytohormones and light responsive regulatory elements. Subcellular localization showed that the given the DlMFT signal localized in the nucleus, expression profiling implied that DlMFT showed significant upregulation during somatic embryogenesis (SE) and zygotic embryogenesis (ZE), and particular highly expressed in late or maturation stages. The accumulation of DlMFT was mainly detected in mature fruit and seed, while it was undetected in abortive seeds, and notably decreased during seed germination. DlMFT responded differentially to exogenous hormones in longan EC. Auxins, salicylic acid (SA) and methyl jasmonate (MeJa) suppressed its expression, however, abscisic acid (ABA), brassinosteroids (BR) showed the opposite function. Meanwhile, DlMFT differentially responded to various abiotic stresses. Our study revealed that DlMFT might be a key regulator of longan somatic and zygotic embryo development, and in seed germination, it is involved in complex plant hormones and abiotic stress signaling pathways.


Assuntos
Proteínas de Transporte/biossíntese , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/biossíntese , Técnicas de Embriogênese Somática de Plantas , Sapindaceae/metabolismo , Sementes/metabolismo , Estresse Fisiológico , Proteínas de Transporte/genética , Reguladores de Crescimento de Planta/genética , Proteínas de Plantas/genética , Sapindaceae/genética , Sementes/genética
17.
Artigo em Inglês | MEDLINE | ID: mdl-29941813

RESUMO

Phosphate-solubilizing bacteria (PSB) can promote plant growth by dissolving insoluble phosphate. Therefore, PSB may have the potential to improve the mobility of heavy metals in soils and enhance phytoextraction. This study isolated a few PSB strains that could dissolve CdCO3 and solid Cd in soil. Two typical PSB, namely, high- and low-Cd-mobilizing PSB (Pseudomonas fluorescens gim-3 and Bacillus cereus qh-35, respectively), were selected to analyze the metabolic profiles, metabolic pathways, and mechanisms of mobilization of insoluble Cd. A total of 34 metabolites secreted by the two PSB strains were identified. Gluconic acid was the main contributor to Cd dissolution (42.4%) in high-Cd-mobilizing PSB. By contrast, gluconic acid was not secreted in low-Cd-mobilizing PSB. Metabolic pathway analysis showed that gluconic acid was produced by the peripheral direct oxidation pathway. Hence, PSB with peripheral direct oxidation pathway were likely to have high-Cd-mobilizing capacity.


Assuntos
Bacillus cereus/fisiologia , Cádmio/química , Gluconatos/química , Pseudomonas fluorescens/fisiologia , Poluentes do Solo/química , Redes e Vias Metabólicas , Fosfatos/química , Solo , Microbiologia do Solo , Solubilidade
18.
World Neurosurg ; 114: e1079-e1085, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29605702

RESUMO

OBJECTIVE: To evaluate the clinical effect of the position of stimulation contacts relative to the hyperdirect pathway (HDP) on the alleviation of motor symptoms in patients with Parkinson disease (PD). METHODS: A group of 11 patients diagnosed with idiopathic PD were included in this study, and all selected targets were in the subthalamic nucleus (STN). In 1 patient, a single side electrode was implanted because of unilateral symptoms; in all other patients, bilateral electrodes each containing 4 discrete contacts were implanted. Nine contacts were excluded due to adverse reactions caused by stimulation, and thus a total of 75 active contacts were evaluated using the same stimulus parameters. Fiber tractography results were individually processed using StealthViz software before all data were subjected to statistical analysis. RESULTS: Under the same stimulus parameters, the shortest distance of each contact to the HDP was smaller in group I (n = 45; >50% improvement rate) compared with group II (n = 30; ≤50% improvement rate) (mean, 1.18 ± 0.86 mm vs. 2.14 ± 1.20 mm; t = 3.78; P < 0.05), and the shortest distance had a negative correlation with the improvement of motor symptoms (r = -0.48; P < 0.05). CONCLUSIONS: Stimulation of the HDP coincided with the improvement of motor symptoms in patients with PD. We propose an improvement of the direct visualization method based on diffusion tensor imaging fiber tractography of the HDP to select the motor part of the STN. Further rigorous clinical trials are needed to verify the value of this method for achieving precise target location and individualized treatment.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Estimulação Encefálica Profunda/métodos , Imagem de Tensor de Difusão/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/cirurgia , Núcleo Subtalâmico/diagnóstico por imagem , Idoso , Córtex Cerebral/fisiologia , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Doença de Parkinson/fisiopatologia , Estudos Retrospectivos , Núcleo Subtalâmico/fisiologia , Resultado do Tratamento
19.
Clin Neurophysiol ; 129(6): 1242-1253, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29674090

RESUMO

OBJECTIVES: The nucleus accumbens (NAc) is known to regulate the motivation and underlie addictive behaviors, and the anterior limb of the internal capsule (ALIC) is involved in several psychiatric disorders. Our study aimed to explore the functions of NAc and ALIC electrophysiologically. METHODS: The local field potentials (LFPs) of the NAc and ALIC were recorded from 7 heroin addicts treated with deep brain stimulation. Correlation analysis was made between LFP powers in various frequency bands and the subjects' neuropsychological test scores; coherence was calculated for the LFPs in NAc and ALIC. RESULTS: Both the NAc and ALIC exhibited prominent theta and alpha frequency band activity in the LFP power spectra. Additionally, a distinct beta band peak was detected in the power spectra of ALIC LFPs, which may represent the activity of striatal bridge cells. There was a significant negative correlation between the power of the theta frequency band of ALIC LFPs and visual analogue scale (VAS) scores indicative of cravings (Spearman's ρ = -0.758, P = 0.002), and a significant positive correlation was found between the power of the alpha frequency band of NAc LFPs and subjects' scores on the Hamilton depression inventory (ρ = 0.727, P = 0.005). LFPs of the NAc and ALIC exhibited higher coherence values in the theta and alpha frequency bands. CONCLUSIONS: The results suggest that theta power in the ALIC/dorsal striatum and alpha power in the NAc may be associated with drug cravings and depressive symptoms, respectively, in heroin addicts. For these subjects, the neural activities in the dorsal and ventral striatum were mainly coordinated within the low-frequency band. SIGNIFICANCE: The study illustrates the neurophysiologic characteristics of heroin addiction and its comorbidities, providing a potential theoretical basis for optimizing deep brain stimulation (DBS) therapy.


Assuntos
Potenciais de Ação/fisiologia , Dependência de Heroína/fisiopatologia , Cápsula Interna/fisiopatologia , Núcleo Accumbens/fisiopatologia , Adulto , Estimulação Encefálica Profunda , Eletroencefalografia , Feminino , Dependência de Heroína/terapia , Humanos , Masculino , Pessoa de Meia-Idade
20.
Inorg Chem ; 57(3): 916-920, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29323484

RESUMO

A quaternary narrow-band-gap semiconductor, Ba2Cr4GeSe10, has been discovered by solid-state reaction. It features a new structure type and crystallizes in the triclinic space group P1̅ (No. 2). The featured 2D anionic layers are constructed by condensed CrSe6 octahedra that are stacking along the c axis, with dispersed GeSe4 tetrahedra and located Ba2+ cations forming these layers. The energy-band structure shows a clear separation between the region of electronic conduction and the zone of electronic insulation. Significantly, an undoped Ba2Cr4GeSe10 sample shows a desirable low thermal conductivity κT (0.51-0.87 W/m·K) and a high Seebeck coefficient S (351-404 µV/K) and reaches a ZT ≈ 0.08 at 773 K.

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