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1.
Bioresour Technol ; 303: 122940, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32044649

RESUMO

This study aimed to evaluate algal growth, lipid production, and nutrient removal in chicken farm flushing wastewater (CFFW). The excessive ammonia nitrogen (EAN) content in the CFFW wastewater represented a major factor limiting the algal growth. A strategy of mixing CFFW with municipal wastewater (MW) that contained less ammonia nitrogen was adopted. The results showed that the mixed wastewaters reduced ammonia nitrogen content, balanced nutrient profile, and promoted biomass production. The residual nutrients in mixed wastewaters were significantly reduced due to the algal absorption. Furthermore, alga grown on mixed wastewaters accumulated a higher level of total lipids and monounsaturated fatty acids that can be used for biodiesel production. The key issue of low biomass yield of algal grown on CFFW due to the inhibition of EAN was efficiently resolved by mitigating limiting factor to algal growth basing on mixing strategy, and accordingly the nutrients in the wastewater were significantly removed.


Assuntos
Chlorella , Microalgas , Amônia , Animais , Biocombustíveis , Biomassa , Galinhas , Fazendas , Lipídeos , Nitrogênio , Nutrientes , Fósforo , Águas Residuárias
2.
Int J Nanomedicine ; 14: 9707-9719, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849463

RESUMO

Introduction: Increased use of silver nanoparticles (AgNPs) has raised concerns that AgNPs may induce toxic effects. In vitro studies of cell monolayers and in vivo studies have produced conflicting results. The inconsistency of these results has been mainly due to limitations of two-dimensional (2D) monolayer cell systems. Methods: A three-dimensional (3D) epidermal model called EpiKutis®, which exhibits good tissue viability and barrier function was developed. The cytotoxicity of AgNPs against EpiKutis was compared to that against 2D keratinocytes at equivalent AgNPs doses (0.035, 0.07, 0.14, 0.28, and 0.56 ng per cell). The amount and distribution of AgNPs in the 3D EpiKutis and 2D keratinocytes after exposure were determined. The toxic mechanisms of AgNPs, such as oxidative stress and production of pro-inflammatory cytokines, were investigated. Results: The results demonstrated that cell viability was greater than 80% and lactate dehydrogenase (LDH) release did not increase even at the highest dose of AgNPs in EpiKutis. In contrast, treatment of 2D keratinocytes with AgNPs resulted in dose-dependent decrease in cell viability from 63% to 11%, and a dose-dependent increase in LDH release from 8% to 16%. Cytotoxicity of AgNPs in 2D keratinocytes was related to oxidative damage and inflammation, as evidenced by increased levels of reactive oxygen species (ROS), malondialdehyde (MDA), IL-1α, IL-6, and IL-8. In addition, levels of superoxide dismutase (SOD) were decreased. EpiKutis treated with AgNPs did not exhibit increased oxidative damage or inflammation, which may have been due to the barrier properties of the 3D structure, resulting in reduced penetration of AgNPs. At equivalent per cell doses, total silver penetration into EpiKutis was 0.9 ± 0.1%, and total silver penetration into 2D keratinocytes was 8.8 ± 0.6% detected by ICP-MS. The penetration and distribution of AgNPs in 2D keratinocytes were confirmed by the TEM-EDS analysis, which was not found in the 3D EpiKutis. These results showed that AgNPs penetrated EpiKutis to a lesser degree than they penetrated 2D keratinocytes, which suggested that EpiKutis exhibited significant barrier function. Discussion: The results of this study showed that AgNP toxicity should be evaluated using 3D epidermal models, which may provide better estimates of in vivo conditions than 2D models. The EpiKutis model may be an ideal model for assessment of nanotoxicity.

3.
J Sep Sci ; 42(18): 3033-3040, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31257725

RESUMO

Alarelin, a gonadotropin-releasing hormone analogue, is widely used in China for the treatment of endometriosis and uterine leiomyoma. In order to investigate its pharmacokinetic behavior and support the preclinical application of new formulations, we have developed a novel and highly selective bioanalytical method to determine alarelin in rat plasma based on liquid chromatography tandem mass spectrometry with triple stage fragmentation. After sample preparation by protein precipitation followed by reversed phase solid phase extraction, alarelin and triptorelin (internal standard) were chromatographed on an Ascentis® Express C18 column (50 mm × 4.6 mm, 2.7 µm) using gradient elution with 0.1% formic acid in water and acetonitrile at a flow rate of 1 mL/min. Detection was by positive mode electrospray ionization followed by triple stage fragmentation using the transitions at m/z 584.6→249.1→221.0 for alarelin and 656.5→249.1→176.0 for triptorelin, The assay was linear in the concentration range 0.3-10 ng/mL with excellent precision and accuracy. It was successfully applied to a pharmacokinetic study in rats administered a dose of 13.5 µg/kg alarelin by intramuscular injection. The results show that the triple stage fragmentation strategy allows highly selective analysis of alarelin and has the potential to be widely applied to the bioassay of other peptidic drugs.

4.
Adv Drug Deliv Rev ; 143: 97-114, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31255595

RESUMO

Nanocarriers (NCs) are a type of drug delivery system commonly used to regulate the pharmacokinetic and pharmacodynamic properties of drugs. Although a wide variety of NCs has been developed, relatively few have been registered for clinical trials and even fewer are clinically approved. Overt or potential toxicity, indistinct mechanisms of drug release and unsatisfactory pharmacokinetic behavior all contribute to their high failure rate during preclinical and clinical testing. These negative characteristics are not only due to the NCs themselves but also to the materials of the drug nanocarrier system (MDNS) that are released in vivo. In this article, we review the main analytical techniques used for bioassay of NCs and MDNS and their pharmacokinetics after administration by various routes. We anticipate our review will serve to improve the understanding of MDNS pharmacokinetics and facilitate the development of NC drug delivery systems.

5.
J Biosci Bioeng ; 128(6): 755-765, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31277909

RESUMO

The diatom microalgal Phaeodactylum tricornutum accumulates a large amount of fucoxanthin. Carotenoids hydroxylases (CHYs) play key roles in fucoxanthin biosynthesis in diatoms. However, not any type of CHYs had been identified in P. tricornutum. In this study, two genes (designated Ptrcyp97b1 and Ptrcyp97b2) were cloned, identified and functionally characterized. They shared high sequence identity (50-94 %) with lutein deficient 1-like proteins from other eukaryotes. The typical catalytic active motifs of cytochrome P450s (CYP) were detected in the amino acid sequences of PtrCYP97B1 and PtrCYP97B2. The two genes were probably due to gene duplication. Ptrcyp97b1 and Ptrcyp97b2 transcriptional expression was up-regulated with distinct patterns under high light conditions. The metabolic profiles of the major carotenoids (ß-carotene, zeaxanthin, diadinoxanthin, diatoxanthin and fucoxanthin) were determined based on the high performance liquid chromatography method. The fucoxanthin and diatoxanthin contents were increased, while the ß-carotene content was decreased. By truncation of the N-terminal trans-membrane anchor or chloroplast transit peptide and addition of a 6 × His-tag, PtrCYP97B1 and PtrCYP97B2 were separately heterologously produced in Escherichia coli and purified by Ni-NTA affinity chromatography. Functional analysis showed that PrtCYP97B2 was able to catalyze the hydroxylation of the ß-rings of ß-carotene to produce zeaxanthin in ß-carotene-accumulating E. coli BL21(DE3) cells. PtrCYP97B1 might have the ability to catalyze the hydroxylation of other substrates other than ß-carotene. These results contribute to the further elucidation of xanthophyll biosynthesis in diatoms.


Assuntos
Carotenoides/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Diatomáceas/enzimologia , Clonagem Molecular , Sistema Enzimático do Citocromo P-450/genética , Diatomáceas/genética , Escherichia coli/genética , Hidroxilação
6.
BMC Plant Biol ; 19(1): 232, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159725

RESUMO

BACKGROUND: Compared with white-fleshed sweetpotato (WFSP), purple-fleshed sweetpotato (PFSP) is a desirable resource for functional food development because of the abundant anthocyanin accumulation in its tuberous roots. Some studies have shown that the expression regulation mediated by miRNA plays an important role in anthocyanin biosynthesis in plants. However, few miRNAs and their corresponding functions related to anthocyanin biosynthesis in tuberous roots of sweetpotato have been known. RESULTS: In this study, small RNA (sRNA) and degradome libraries from the tuberous roots of WFSP (Xushu-18) and PFSP (Xuzishu-3) were constructed, respectively. Totally, 191 known and 33 novel miRNAs were identified by sRNA sequencing, and 180 target genes cleaved by 115 known ib-miRNAs and 5 novel ib-miRNAs were identified by degradome sequencing. Of these, 121 miRNAs were differently expressed between Xushu-18 and Xuzishu-3. Integrated analysis of sRNA, degradome sequencing, GO, KEGG and qRT-PCR revealed that 26 differentially expressed miRNAs and 36 corresponding targets were potentially involved in the anthocyanin biosynthesis. Of which, an inverse correlation between the expression of ib-miR156 and its target ibSPL in WFSP and PFSP was revealed by both qRT-PCR and sRNA sequencing. Subsequently, ib-miR156 was over-expressed in Arabidopsis. Interestingly, the ib-miR156 over-expressing plants showed suppressed abundance of SPL and a purplish phenotype. Concomitantly, upregulated expression of four anthocyanin pathway genes was detected in transgenic Arabidopsis plants. Finally, a putative ib-miRNA-target model involved in anthocyanin biosynthesis in sweetpotato was proposed. CONCLUSIONS: The results represented a comprehensive expression profiling of miRNAs related to anthocyanin accumulation in sweetpotato and provided important clues for understanding the regulatory network of anthocyanin biosynthesis mediated by miRNA in tuberous crops.


Assuntos
Antocianinas/biossíntese , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , MicroRNAs/genética , RNA de Plantas/genética , Antocianinas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Ipomoea batatas/metabolismo , MicroRNAs/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , RNA de Plantas/metabolismo , Análise de Sequência de RNA
7.
Front Plant Sci ; 10: 703, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214221

RESUMO

Palmitoleic acid (16:1Δ9) is one kind of ω-7 fatty acids (ω-7 FAs) widely used in food, nutraceutical and industry. However, such high-valued ω-7 FA only has a trace level in mature seeds of cotton and other common oil crops. We found that palmitoleic acid (>10.58 Mol%) was specially enriched in developing cotton endosperm which is disappeared in its mature seed. The present study was conducted to investigate the mechanism underlying high accumulation of palmitoleic acid in developing endosperm but not in embryo of upland cotton (Gossypium hirsutum L.) seed. Of 17 stearoyl-ACP Δ9 desaturases (SAD) gene family members identified in upland cotton, six GhSADs may specifically work in the desaturation of palmitic acid (16:0-ACP) to produce palmitoleic acid (16:1Δ9-ACP), which were revealed by examining the key amino acids in the catalytic center and their cis-elements. Gene expression analysis showed that spatial patterns of these GhSADs were different in developing ovules, with GhA-SAD6 and GhD-SAD8 preferentially expressed in developing endosperms. Functional analysis by transient expression in Nicotiana benthamiana leaves and genetic complementary assay using yeast mutant BY4389 strain unable to synthesize unsaturated fatty acids demonstrated that GhA-SAD6 and GhD-SAD8 have strong substrate specificity for 16:0-ACP. In contrast, GhA-SAD5 and GhA-SAD7 exhibited high specific activity on 18:0-ACP. Taken together, these data evidence that GhA-SAD6 and GhD-SAD8 are responsible for making palmitoleic acid in developing cotton endosperms, and provide endogenous gene targets for genetic modification to enrich ω-7 FAs in cotton seed oil required for sustainable production of functionality-valued products.

8.
Front Genet ; 10: 351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068968

RESUMO

Chronic diseases are one of the biggest threats to human life. It is clinically significant to predict the chronic disease prior to diagnosis time and take effective therapy as early as possible. In this work, we use problem transform methods to convert the chronic diseases prediction into a multi-label classification problem and propose a novel convolutional neural network (CNN) architecture named GroupNet to solve the multi-label chronic disease classification problem. Binary Relevance (BR) and Label Powerset (LP) methods are adopted to transform multiple chronic disease labels. We present the correlated loss as the loss function used in the GroupNet, which integrates the correlation coefficient between different diseases. The experiments are conducted on the physical examination datasets collected from a local medical center. In the experiments, we compare GroupNet with other methods and models. GroupNet outperforms others and achieves the best accuracy of 81.13%.

9.
Int J Biol Macromol ; 133: 1090-1101, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054300

RESUMO

The aim of this study is to probe new functions of a polysaccharide from Spirulina platensis (PSP) on constipation and intestinal microbiota in mice. Diphenoxylate-induced constipation in mice was treated with different doses of PSP, followed by examining the defecation patterns, levels of acetyl cholinesterase (AchE), nitric oxide (NO), and tissue section histopathology. The composition of intestinal microbiota was determined by genome sequencing analysis of the 16S rDNA. This study found that the average molecular weight of PSP was 29, 600 Da, and mainly monosaccharides of PSP were rhamnose (24.7%), glucose (16.15%) and galactose (13.32%). The beneficial effects of PSP treatment include defecation improvement, increase of AchE activity, reduction of NO concentration, renovation of the damaged intestinal villus and affection on the expression of some related genes in the constipated mice. In addition, PSP had significant effects on the gut microbiota, showing the enhancement in abundance of beneficial bacteria including Akkermansia, Lactobacillus, Butyricimonas, Candidatus Arthromitus and Prevotella, and the reduction in abundance of harmful bacteria such as Clostridium and Dorea. The present s uncovered a new function of PSP, indicating that PSP could be used in constipation therapies.


Assuntos
Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Difenoxilato/efeitos adversos , Polissacarídeos Bacterianos/farmacologia , Spirulina/química , Animais , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/metabolismo , Constipação Intestinal/metabolismo , Constipação Intestinal/fisiopatologia , Defecação/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurotransmissores/metabolismo , Polissacarídeos Bacterianos/uso terapêutico , Água/metabolismo
10.
Sheng Wu Gong Cheng Xue Bao ; 34(9): 1478-1490, 2018 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-30255682

RESUMO

Enhancing soybean (Glycine max) oil production is crucial to meet the market demand of vegetable oil. Diacylglycerol acyltransferase (DGAT) catalyzes the final acylation reaction of triacylglycerol (TAG) synthesis, acting as one of the rate-limiting enzymes for oil biosynthesis in plant seeds. Here, a cDNA clone VgDGAT1A encoding the DGAT1 protein was isolated from the high oil plant Vernonia galamensis. VgDGAT1A was specifically overexpressed in soybean seeds, and several high-generation transgenic lines (T7) were obtained by continuous selection. qPCR analysis showed that VgDGAT1A was highly expressed in the mid-development stage (30-45 DAF) of the transgenic seeds. Accordingly, the DGAT enzyme activity in the transgenic seeds was increased by 7.8 folds in comparison with the wild-type controls. Seed oil and starch contents were, respectively, increased by 5.1% (Dry weight) and reduced by 2%-3% in the transgenic soybeans. Importantly, protein content was not significantly different between transgenic and control seeds. Seed weight and germination rate of the transgenic lines exhibited no negative effect. Fatty acid profiling demonstrated that antioxidant oleic acid (C18:1Δ9) content in the transgenic seed oil was elevated by 8.2% compared to the control, and correspondingly, easily-oxidized linoleic acid (C18:2Δ9,12) and linolenic acid (C18:3Δ9,12,15) were decreased by 6% and 2% respectively. Taken together, seed-specific overexpression of an exogenous VgDGAT1A gene can break the negative linkage of oil and protein contents in soybean seeds, indicating that engineering of this highly-active DGAT enzyme is an effective strategy to improve oil yield and nutritional value in oilseeds.


Assuntos
Diacilglicerol O-Aciltransferase/genética , Óleos Vegetais/química , Proteínas de Plantas/genética , Sementes/química , Soja/química , Valor Nutritivo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Soja/genética , Vernonia/genética
11.
Int J Mol Sci ; 19(9)2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30227676

RESUMO

The basic leucine-region zipper (bZIP) transcription factors (TFs) act as crucial regulators in various biological processes and stress responses in plants. Currently, bZIP family members and their functions remain elusive in the green unicellular algae Chlamydomonas reinhardtii, an important model organism for molecular investigation with genetic engineering aimed at increasing lipid yields for better biodiesel production. In this study, a total of 17 C. reinhardtii bZIP (CrebZIP) TFs containing typical bZIP structure were identified by a genome-wide analysis. Analysis of the CrebZIP protein physicochemical properties, phylogenetic tree, conserved domain, and secondary structure were conducted. CrebZIP gene structures and their chromosomal assignment were also analyzed. Physiological and photosynthetic characteristics of C. reinhardtii under salt stress were exhibited as lower cell growth and weaker photosynthesis, but increased lipid accumulation. Meanwhile, the expression profiles of six CrebZIP genes were induced to change significantly during salt stress, indicating that certain CrebZIPs may play important roles in mediating photosynthesis and lipid accumulation of microalgae in response to stresses. The present work provided a valuable foundation for functional dissection of CrebZIPs, benefiting the development of better strategies to engineer the regulatory network in microalgae for enhancing biofuel and biomass production.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Chlamydomonas reinhardtii/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Estresse Salino , Sequência de Aminoácidos , Fatores de Transcrição de Zíper de Leucina Básica/química , Chlamydomonas reinhardtii/química , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Metabolismo dos Lipídeos , Fotossíntese , Filogenia , Proteínas de Plantas/química , Conformação Proteica , Domínios Proteicos
12.
ACS Appl Mater Interfaces ; 10(34): 28494-28501, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30085647

RESUMO

Surface modifications can endow nanomaterials with presupposed immunoregulatory functions to optimize vaccine-induced immune responses. In this work, we modified an immunoregulatory molecule, amantadine (Ada), on the outermost layer of PVP-PEG-coated silver nanorods (Ada-PVP-PEG silver nanorods). Such Ada surface-modified silver nanorods promote HIV vaccine-triggered cytotoxic lymphocytes (CTLs) to produce around eightfold stronger tumor necrosis factor alpha (TNF-α) in vivo. The enhancement of HIV-specific CTL-derived TNF-α significantly facilitates the death of HIV-infected cells (from 28.86 to 84.19%) and reduces HIV production (around sixfold). This work supports the critical role of surface modifications of nanomaterials in fundamentally improving the immunotherapy of HIV vaccine against HIV-infected cells.


Assuntos
Nanotubos , Vacinas contra a AIDS , Amantadina , HIV-1 , Humanos , Imunoterapia , Prata , Linfócitos T Citotóxicos
13.
PeerJ ; 6: e4796, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868257

RESUMO

Plant-specific GRAS transcription factors regulate various biological processes in plant growth, development and stress responses. However, this important gene family was not fully characterized in pepper (Capsicum annuum L.), an economically important vegetable crop. Here, a total of 50 CaGRAS members were identified in pepper genome and renamed by their respective chromosomal distribution. Genomic organization revealed that most CaGRAS genes (84%) have no intron. Phylogenetic analysis divided pepper CaGRAS members into 10 subfamilies, with each having distinct conserved domains and functions. For the expansion of the GRAS genes in pepper, segmental duplication contributed more than tandem duplication did. Gene expression analysis in various tissues demonstrated that most of CaGRAS genes exhibited a tissue- and development stage-specific expression pattern, uncovering their potential functions in pepper growth and development. Moreover, 21 CaGRAS genes were differentially expressed under cold, drought, salt and gibberellin acid (GA) treatments, indicating that they may implicated in plant response to abiotic stress. Notably, GA responsive cis-elements were detected in the promoter regions of the majority of CaGRAS genes, suggesting that CaGRAS may involve in signal cross-talking. The first comprehensive analysis of GRAS gene family in pepper genome by this study provide insights into understanding the GRAS-mediated regulation network, benefiting the genetic improvements in pepper and some other relative plants.

14.
Int J Mol Sci ; 19(1)2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29303957

RESUMO

The plant-specific WRINKLED1 (WRI1) is a member of the AP2/EREBP class of transcription factors that positively regulate oil biosynthesis in plant tissues. Limited information is available for the role of WRI1 in oil biosynthesis in castor bean (Ricinus connunis L.), an important industrial oil crop. Here, we report the identification of two alternatively spliced transcripts of RcWRI1, designated as RcWRI1-A and RcWRI1-B. The open reading frames of RcWRI1-A (1341 bp) and RcWRI1-B (1332 bp) differ by a stretch of 9 bp, such that the predicted RcWRI1-B lacks the three amino acid residues "VYL" that are present in RcWRI1-A. The RcWRI1-A transcript is present in flowers, leaves, pericarps and developing seeds, while the RcWRI1-B mRNA is only detectable in developing seeds. When the two isoforms were individually introduced into an Arabidopsiswri1-1 loss-of-function mutant, total fatty acid content was almost restored to the wild-type level, and the percentage of the wrinkled seeds was largely reduced in the transgenic lines relative to the wri1-1 mutant line. Transient expression of each RcWRI1 splice isoform in N. benthamiana leaves upregulated the expression of the WRI1 target genes, and consequently increased the oil content by 4.3-4.9 fold when compared with the controls, and RcWRI1-B appeared to be more active than RcWRI1-A. Both RcWRI1-A and RcWRI1-B can be used as a key transcriptional regulator to enhance fatty acid and oil biosynthesis in leafy biomass.


Assuntos
Óleo de Rícino/biossíntese , Ácidos Graxos/biossíntese , Proteínas de Plantas/genética , Tabaco/genética , Fatores de Transcrição/genética , Transgenes , Processamento Alternativo , Óleo de Rícino/genética , Ácidos Graxos/genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Ricinus/genética , Tabaco/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima
15.
J Pharm Biomed Anal ; 151: 260-265, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29358126

RESUMO

Eptifibatide is a therapeutic cyclic peptide with poor collision-induced dissociation (CID) efficiency for multiple reaction monitoring (MRM), which limits the development of a traditional liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioassay with MRM. In this study, a method combining differential mobility spectrometry (DMS) with liquid chromatography-multiple ion monitoring (LC-DMS-MIM) was developed for the quantitation of eptifibatide in rat plasma. After solid phase extraction (SPE) of 100 µL plasma on an Oasis® HLB cartridge, the analyte and I.S. (octreotide) were analyzed using a SCIEX QTRAP 6500 operated in the positive ion mode and preceded by a DMS device. The lower limit of quantitation (LLOQ) for eptifibatide was 0.5 ng/mL using only 100 µL plasma. The method was linear in the concentration range 0.5-300 ng/mL with good precision and accuracy. Compared to regulated quantitative LC-MS/MS bioanalysis of eptifibatide, the LC-DMS-MIM method effectively overcomes the sensitivity challenge in the LC-MRM method and reduces the high background noise and matrix interference in LC-MIM method without DMS. The method was successfully applied to a pharmacokinetic study involving intravenous injection of eptifibatide to Wistar rats.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Peptídeos/farmacocinética , Inibidores da Agregação de Plaquetas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Eptifibatida , Feminino , Limite de Detecção , Masculino , Peptídeos/sangue , Inibidores da Agregação de Plaquetas/sangue , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/instrumentação
16.
J Cell Physiol ; 233(2): 1574-1584, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28621459

RESUMO

Osteoblast differentiation is a multistep process delicately regulated by many factors, including cytoskeletal dynamics and signaling pathways. Microtubule actin crosslinking factor 1 (MACF1), a key cytoskeletal linker, has been shown to play key roles in signal transduction and in diverse cellular processes; however, its role in regulating osteoblast differentiation is still needed to be elucidated. To further uncover the functions and mechanisms of action of MACF1 in osteoblast differentiation, we examined effects of MACF1 knockdown (MACF1-KD) in MC3T3-E1 osteoblastic cells on their osteoblast differentiation and associated molecular mechanisms. The results showed that knockdown of MACF1 significantly suppressed mineralization of MC3T3-E1 cells, down-regulated the expression of key osteogenic genes alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2) and type I collagen α1 (Col Iα1). Knockdown of MACF1 dramatically reduced the nuclear translocation of ß-catenin, decreased the transcriptional activation of T cell factor 1 (TCF1), and down-regulated the expression of TCF1, lymphoid enhancer-binding factor 1 (LEF1), and Runx2, a target gene of ß-catenin/TCF1. In addition, MACF1-KD increased the active level of glycogen synthase kinase-3ß (GSK-3ß), which is a key regulator for ß-catenin signal transduction. Moreover, the reduction of nuclear ß-catenin amount and decreased expression of TCF1 and Runx2 were significantly reversed in MACF1-KD cells when treated with lithium chloride, an agonist for ß-catenin by inhibiting GSK-3ß activity. Taken together, these findings suggest that knockdown of MACF1 in osteoblastic cells inhibits osteoblast differentiation through suppressing the ß-catenin/TCF1-Runx2 axis. Thus, a novel role of MACF1 in and a new mechanistic insight of osteoblast differentiation are uncovered.


Assuntos
Diferenciação Celular , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Proteínas dos Microfilamentos/metabolismo , Osteoblastos/metabolismo , Osteogênese , beta Catenina/metabolismo , Células 3T3 , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Cloreto de Lítio/farmacologia , Camundongos , Proteínas dos Microfilamentos/genética , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Fenótipo , Fosforilação , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Transfecção , beta Catenina/agonistas , beta Catenina/genética
17.
J Healthc Eng ; 2017: 5967302, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29118963

RESUMO

Nowadays, providing high-quality recommendation services to users is an essential component in web applications, including shopping, making friends, and healthcare. This can be regarded either as a problem of estimating users' preference by exploiting explicit feedbacks (numerical ratings), or as a problem of collaborative ranking with implicit feedback (e.g., purchases, views, and clicks). Previous works for solving this issue include pointwise regression methods and pairwise ranking methods. The emerging healthcare websites and online medical databases impose a new challenge for medical service recommendation. In this paper, we develop a model, MBPR (Medical Bayesian Personalized Ranking over multiple users' actions), based on the simple observation that users tend to assign higher ranks to some kind of healthcare services that are meanwhile preferred in users' other actions. Experimental results on the real-world datasets demonstrate that MBPR achieves more accurate recommendations than several state-of-the-art methods and shows its generality and scalability via experiments on the datasets from one mobile shopping app.


Assuntos
Serviços de Saúde , Modelos Estatísticos , Preferência do Paciente , Algoritmos , Teorema de Bayes , Conjuntos de Dados como Assunto , Internet , Preferência do Paciente/estatística & dados numéricos , Encaminhamento e Consulta
18.
J Healthc Eng ; 2017: 8051673, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29065647

RESUMO

It is important to identify and prevent disease risk as early as possible through regular physical examinations. We formulate the disease risk prediction into a multilabel classification problem. A novel Ensemble Label Power-set Pruned datasets Joint Decomposition (ELPPJD) method is proposed in this work. First, we transform the multilabel classification into a multiclass classification. Then, we propose the pruned datasets and joint decomposition methods to deal with the imbalance learning problem. Two strategies size balanced (SB) and label similarity (LS) are designed to decompose the training dataset. In the experiments, the dataset is from the real physical examination records. We contrast the performance of the ELPPJD method with two different decomposition strategies. Moreover, the comparison between ELPPJD and the classic multilabel classification methods RAkEL and HOMER is carried out. The experimental results show that the ELPPJD method with label similarity strategy has outstanding performance.


Assuntos
Diagnóstico por Computador/métodos , Aprendizado de Máquina , Informática Médica/métodos , Reconhecimento Automatizado de Padrão/métodos , Medição de Risco/métodos , Algoritmos , Inteligência Artificial , Colecistite/diagnóstico , Diabetes Mellitus/diagnóstico , Fígado Gorduroso/diagnóstico , Cardiopatias/diagnóstico , Humanos , Hipertensão/diagnóstico , Obesidade/diagnóstico , Software
19.
Front Plant Sci ; 8: 1557, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28955354

RESUMO

Calreticulin (CRT), an endoplasmic reticulum (ER)-localized Ca2+-binding/buffering protein, is highly conserved and extensively expressed in animal and plant cells. To understand the function of CRTs in wheat (Triticum aestivum L.), particularly their roles in stress tolerance, we cloned the full-length genomic sequence of the TaCRT-D isoform from D genome of common hexaploid wheat, and characterized its function by transgenic Arabidopsis system. TaCRT-D exhibited different expression patterns in wheat seedling under different abiotic stresses. Transgenic Arabidopsis plants overexpressing ORF of TaCRT-D displayed more tolerance to drought, cold, salt, mannitol, and other abiotic stresses at both seed germination and seedling stages, compared with the wild-type controls. Furthermore, DNA polymorphism analysis and gene mapping were employed to develop the functional markers of this gene for marker-assistant selection in wheat breeding program. One SNP, S440 (T→C) was detected at the TaCRT-D locus by genotyping a wheat recombinant inbred line (RIL) population (114 lines) developed from Opata 85 × W7984. The TaCRT-D was then fine mapped between markers Xgwm645 and Xgwm664 on chromosome 3DL, corresponding to genetic distances of 3.5 and 4.4 cM, respectively, using the RIL population and Chinese Spring nulli-tetrasomic lines. Finally, the genome-specific and allele-specific markers were developed for the TaCRT-D gene. These findings indicate that TaCRT-D function importantly in plant stress responses, providing a gene target for genetic engineering to increase plant stress tolerance and the functional markers of TaCRT-D for marker-assistant selection in wheat breeding.

20.
Biol Open ; 6(7): 1024-1034, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28679505

RESUMO

As an important oilseed worldwide, Camelina sativa is being increasingly explored for its use in production of food, feed, biofuel and industrial chemicals. However, detailed mechanisms of camelina oil biosynthesis and accumulation, particularly in vegetative tissues, are understood to a very small extent. Here, we present genome-wide identification, cloning and functional analysis of phospholipid diacylglycerol acyltransferase (PDAT) in C. sativa, which catalyses the final acylation step in triacylglycerol (TAG) biosynthesis by transferring a fatty acyl moiety from a phospholipid to diacylglycerol (DAG). We identified five genes (namely CsPDAT1-A, B, and C and CsPDAT2-A and B) encoding PDATs from the camelina genome. CsPDAT1-A is mainly expressed in seeds, whereas CsPDAT1-C preferentially accumulates in flower and leaf tissues. High expression of CsPDAT2-A and CsPDAT2-B was detected in stem and root tissues, respectively. Cold stress induced upregulation of CsPDAT1-A and CsPDAT1-C expression by 3.5- and 2.5-fold, respectively, compared to the control. Salt stress led to an increase in CsPDAT2-B transcripts by 5.1-fold. Drought treatment resulted in an enhancement of CsPDAT2-A mRNAs by twofold and a reduction of CsPDAT2-B expression. Osmotic stress upregulated the expression of CsPDAT1-C by 3.3-fold. Furthermore, the cDNA clones of these CsPDAT genes were isolated for transient expression in tobacco leaves. All five genes showed PDAT enzymatic activity and substantially increased TAG accumulation in the leaves, with CsPDAT1-A showing a higher preference for ɑ-linolenic acid (18:3 ω-3). Overall, this study demonstrated that different members of CsPDAT family contribute to TAG synthesis in different tissues. More importantly, they are involved in different types of stress responses in camelina seedlings, providing new evidence of their roles in oil biosynthesis and regulation in camelina vegetative tissue. The identified CsPDATs may have practical applications in increasing oil accumulation and enhancing stress tolerance in other plants as well.

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