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1.
Eur Radiol ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38337067

RESUMO

OBJECTIVES: Utilising readily available clinical variables, we aimed to develop and validate a novel machine learning (ML) model to predict severe coronary calcification, and further assessed its prognostic significance. METHODS: This retrospective study enrolled patients who underwent coronary CT angiography and subsequent invasive coronary angiography. Multiple ML algorithms were used to train the models for predicting severe coronary calcification (cardiac CT-measured coronary artery calcium [CT-CAC] score ≥ 400). The ML-based CAC (ML-CAC) score derived from the ML predictive probability was stratified into quartiles for prognostic analysis. The primary endpoint was a composite of all-cause death, nonfatal myocardial infarction, or nonfatal stroke. RESULTS: Overall, 5785 patients were divided into training (80%) and test sets (20%). For clinical practicability, we selected the nine-feature support vector machine model with good and satisfactory performance regarding both discrimination and calibration based on five repetitions of the 10-fold cross-validation in the training set (mean AUC = 0.715, Brier score = 0.202), and based on the test in the test set (AUC = 0.753, Brier score = 0.191). In the test set cohort (n = 1137), the primary endpoint was observed in 50 (4.4%) patients during a median 2.8 years' follow-up. The ML-CAC system was significantly associated with an increased risk of the primary endpoint (adjusted hazard ratio for trend 2.26, 95% CI 1.35-3.79, p = 0.002). There was no significant difference in the prognostic value between the ML-CAC and CT-CAC systems (C-index, 0.67 vs. 0.69; p = 0.618). CONCLUSION: ML-CAC score predicted from clinical variables can serve as a novel prognostic indicator in patients referred for invasive coronary angiography. CLINICAL RELEVANCE STATEMENT: In patients referred for invasive coronary angiography who have not undergone preoperative CT-measured coronary artery calcium scoring, machine learning-based coronary artery calcium score assessment can serve as an alternative for predicting the prognosis. KEY POINTS: • The coronary artery calcium (CAC) score, a solid prognostic indicator, can be predicted using non-CT methods. • We developed a machine learning (ML)-CAC model utilising nine clinical variables to predict severe coronary calcification. • The ML-CAC system offers significant prognostic value in patients referred for invasive coronary angiography.

2.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338944

RESUMO

We aimed to test how the postbiotic butyrate impacts select gut bacteria, small intestinal epithelial integrity, and microvascular endothelial activation during acute ethanol exposure in mice and primary human intestinal microvascular endothelial cells (HIMECs). Supplementation during an acute ethanol challenge with or without tributyrin, a butyrate prodrug, was delivered to C57BL/6 mice. A separate group of mice received 3 days of clindamycin prior to the acute ethanol challenge. Upon euthanasia, blood endotoxin, cecal bacteria, jejunal barrier integrity, and small intestinal lamina propria dendritic cells were assessed. HIMECs were tested for activation following exposure to ethanol ± lipopolysaccharide (LPS) and sodium butyrate. Tributyrin supplementation protected a butyrate-generating microbe during ethanol and antibiotic exposure. Tributyrin rescued ethanol-induced disruption in jejunal epithelial barrier, elevated plasma endotoxin, and increased mucosal vascular addressin cell-adhesion molecule-1 (MAdCAM-1) expression in intestinal microvascular endothelium. These protective effects of tributyrin coincided with a tolerogenic dendritic response in the intestinal lamina propria. Lastly, sodium butyrate pre- and co-treatment attenuated the direct effects of ethanol and LPS on MAdCAM-1 induction in the HIMECs from a patient with ulcerative colitis. Tributyrin supplementation protects small intestinal epithelial and microvascular barrier integrity and modulates microvascular endothelial activation and dendritic tolerizing function during a state of gut dysbiosis and acute ethanol challenge.


Assuntos
Células Endoteliais , Etanol , Camundongos , Humanos , Animais , Etanol/farmacologia , Ácido Butírico/farmacologia , Ácido Butírico/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Mucosa Intestinal/metabolismo
3.
J Integr Plant Biol ; 66(7): 1440-1458, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38780111

RESUMO

Grain yield is determined mainly by grain number and grain weight. In this study, we identified and characterized MORE GRAINS1 (MOG1), a gene associated with grain number and grain weight in rice (Oryza sativa L.), through map-based cloning. Overexpression of MOG1 increased grain yield by 18.6%-22.3% under field conditions. We determined that MOG1, a bHLH transcription factor, interacts with OsbHLH107 and directly activates the expression of LONELY GUY (LOG), which encodes a cytokinin-activating enzyme and the cell expansion gene EXPANSIN-LIKE1 (EXPLA1), positively regulating grain number per panicle and grain weight. Natural variations in the promoter and coding regions of MOG1 between Hap-LNW and Hap-HNW alleles resulted in changes in MOG1 expression level and transcriptional activation, leading to functional differences. Haplotype analysis revealed that Hap-HNW, which results in a greater number and heavier grains, has undergone strong selection but has been poorly utilized in modern lowland rice breeding. In summary, the MOG1-OsbHLH107 complex activates LOG and EXPLA1 expression to promote cell expansion and division of young panicles through the cytokinin pathway, thereby increasing grain number and grain weight. These findings suggest that Hap-HNW could be used in strategies to breed high-yielding temperate japonica lowland rice.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Haplótipos/genética , Genes de Plantas , Variação Genética
4.
Biochem Biophys Res Commun ; 672: 145-153, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37354607

RESUMO

Calcific aortic valve disease (CAVD) is an aging related disease characterized by inflammation and fibrocalcific remodeling. IL-17A is a key cytokine associated with pathophysiology of inflammatory and fibrotic disease. Previous studies showed accumulation of IL-17A-producing T helper lymphocytes in human calcified aortic valves and significantly elevated IL-17RA expression in calcified valves. However, the role of IL-17A signaling in the initiation and development of CAVD is still unclear. In this study, by analyzing public transcriptome databases, we found that IL-17A-IL-17RA signaling is activated in calcified valves. Gene expression analysis revealed significantly increased IL-17A, IL-17RA, and RUNX2 expression in calcified human aortic valves compared to in non-calcified valves, and the expression of IL-17A and IL-17RA were positively correlated with RUNX2 expression. A 5/6 nephrectomy was performed in Apoe-/- (Apoe knockout) mice to establish a CAVD mouse model. IL-17A-neutralizing antibodies significantly reduced valve calcium deposition and decreased expression of RUNX2 in aortic valves. Immunofluorescence staining of human aortic valves and qRT-PCR analysis of primary aortic valve cells revealed abundant expression of IL-17RA in valvular endothelial cells (VECs). RNA sequencing indicated that IL-17A promoted the activation of inflammatory signaling pathways in VECs. Furthermore, qRT-PCR and cytometric bead array analysis confirmed that IL-17A promoted the expression or secretion of inflammatory cytokines IL-6 and IL-1ß, chemokines CXCL2 and CXCL8, and fibrosis-related gene COL16A1. Our findings indicate that elevated IL-17A in CAVD may promote valve inflammation, fibrosis, and calcification by inducing endothelial activation and inflammation. Targeting IL-17A-IL-17RA signaling may be a potential therapeutic strategy for CAVD.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Humanos , Camundongos , Animais , Valva Aórtica/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Células Endoteliais/metabolismo , Interleucina-17/metabolismo , Estenose da Valva Aórtica/genética , Citocinas/metabolismo , Inflamação/patologia , Fibrose , Apolipoproteínas E/metabolismo , Células Cultivadas
5.
Circ Res ; 128(1): 8-23, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33092471

RESUMO

RATIONALE: Thoracic aortic aneurysm (TAA) leads to substantial mortality worldwide. Familial and syndromic TAAs are highly correlated with genetics. However, the incidence of sporadic isolated TAA (iTAA) is much higher, and the genetic contribution is not yet clear. OBJECTIVE: Here, we examined the genetic characteristics of sporadic iTAA. METHODS AND RESULTS: We performed a genetic screen of 551 sporadic iTAA cases and 1071 controls via whole-exome sequencing. The prevalence of pathogenic mutations in known causal genes was 5.08% in the iTAA cohort. We selected 100 novel candidate genes using a strict strategy, and the suspected functional variants of these genes were significantly enriched in cases compared with controls and carried by 60.43% of patients. We found more severe phenotypes and a lower proportion of hypertension in cases with pathogenic mutations or suspected functional variants. Among the candidate genes, Testin (TES), which encodes a focal adhesion scaffold protein, was identified as a potential TAA causal gene, accounting for 4 patients with 2 missense variants in the LIM1 domain (c.751T>C encoding p.Y251H; c.838T>C encoding p.Y280H) and highly expressed in the aorta. The 2 variants led to a decrease in TES expression. The thoracic aorta was spontaneously dilated in the TesY249H knock-in and Tes-/- mice. Mechanistically, the p.Y249H variant or knockdown of TES led to the repression of vascular smooth muscle cell contraction genes and disturbed the vascular smooth muscle cell contractile phenotype. Interestingly, suspected functional variants of other focal adhesion scaffold genes, including TLN1 (Talin-1) and ZYX (zyxin), were also significantly enriched in patients with iTAA; moreover, their knockdown resulted in decreased contractility of vascular smooth muscle cells. CONCLUSIONS: For the first time, this study revealed the genetic landscape across iTAA and showed that the focal adhesion scaffold genes are critical in the pathogenesis of iTAA.


Assuntos
Aneurisma da Aorta Torácica/genética , Dissecção Aórtica/genética , Proteínas do Citoesqueleto/genética , Adesões Focais/genética , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Proteínas de Ligação a RNA/genética , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/metabolismo , Dissecção Aórtica/fisiopatologia , Animais , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/fisiopatologia , Estudos de Casos e Controles , Células Cultivadas , Proteínas do Citoesqueleto/metabolismo , Feminino , Adesões Focais/metabolismo , Predisposição Genética para Doença , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Músculo Liso Vascular/diagnóstico por imagem , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiopatologia , Fenótipo , Proteínas de Ligação a RNA/metabolismo , Talina/genética , Talina/metabolismo , Vasoconstrição , Sequenciamento do Exoma , Zixina/genética , Zixina/metabolismo
6.
J Adolesc ; 95(6): 1106-1115, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37089045

RESUMO

BACKGROUND: Nonsuicidal self-injury (NSSI) has garnered growing attention in recent years, and cybervictimization (CV) has been identified as a risk factor for NSSI among adolescents. However, little is known about this association's longitudinal mediating and moderating mechanisms. Guided by the experiential avoidance model, the present study used a short longitudinal design to examine the mediating role of depressive symptoms and the moderating role of emotional reactivity between CV and NSSI. METHODS: A total of 577 Chinese middle school students (Mage = 14.38, SD = 0.67) completed the measures of CV, NSSI, depressive symptoms, and emotional reactivity. They provided data in two waves (T1 and T2, 6 months apart). RESULTS: The results found a longitudinal association between CV and NSSI as well as the mediating role of depressive symptoms. Moreover, emotional reactivity amplified the relationship between CV and NSSI via depressive symptoms; specifically, the relationship between depressive symptoms and NSSI was only significant for adolescents with high emotional reactivity. CONCLUSION: The current study has found that emotional reactivity moderated the indirect effect of depressive symptoms on the relationship between CV and NSSI. These findings have implications for the identification and intervention of NSSI in early adolescents.


Assuntos
Depressão , Comportamento Autodestrutivo , Adolescente , Humanos , Povo Asiático , Depressão/epidemiologia , Depressão/psicologia , Fatores de Risco , Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/psicologia , Cyberbullying/psicologia , População do Leste Asiático
7.
J Biol Chem ; 296: 100483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33647318

RESUMO

Vascular calcification is the ectopic deposition of calcium hydroxyapatite minerals in arterial wall, which involves the transdifferentiation of vascular smooth muscle cells (VSMCs) toward an osteogenic phenotype. However, the underlying molecular mechanisms regulating the VSMC osteogenic switch remain incompletely understood. In this study, we examined the roles of microRNAs (miRNAs) in vascular calcification. miRNA-seq transcriptome analysis identified miR-223-3p as a candidate miRNA in calcified mouse aortas. MiR-223-3p knockout aggravated calcification in both medial and atherosclerotic vascular calcification models. Further, RNA-seq transcriptome analysis verified JAK-STAT and PPAR signaling pathways were upregulated in both medial and atherosclerotic calcified aortas. Overlapping genes in these signaling pathways with predicted target genes of miR-223-3p derived from miRNA databases, we identified signal transducer and activator of transcription 3 (STAT3) as a potential target gene of miR-223-3p in vascular calcification. In vitro experiments showed that miR-223-3p blocked interleukin-6 (IL-6)/STAT3 signaling, thereby preventing the osteogenic switch and calcification of VSMCs. In contrast, overexpression of STAT3 diminished the effect of miR-223-3p. Taken together, the results indicate a protective role of miR-223-3p that inhibits both medial and atherosclerotic vascular calcification by regulating IL-6/STAT3 signaling-mediated VSMC transdifferentiation.


Assuntos
Aorta/metabolismo , Interleucina-6/metabolismo , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Osteogênese/fisiologia , Fator de Transcrição STAT3/metabolismo , Animais , Aorta/patologia , Transdiferenciação Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Interleucina-6/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Músculo Liso Vascular/citologia , Músculo Liso Vascular/patologia , Fator de Transcrição STAT3/genética , Transdução de Sinais , Calcificação Vascular/genética , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Calcificação Vascular/prevenção & controle
8.
J Biol Chem ; 295(30): 10212-10223, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32493731

RESUMO

After injury, the coordinated balance of pro- and anti-inflammatory factors in the microenvironment contribute to skeletal muscle regeneration. However, the underlying molecular mechanisms regulating this balance remain incompletely understood. In this study, we examined the roles of microRNAs (miRNAs) in inflammation and muscle regeneration. miRNA-Seq transcriptome analysis of mouse skeletal muscle revealed that miR-223-3p is upregulated in the early stage of muscle regeneration after injury. miR-223-3p knockout resulted in increased inflammation, impaired muscle regeneration, and increased interstitial fibrosis. Mechanistically, we found that myeloid-derived miR-223-3p suppresses the target gene interleukin-6 (Il6), associated with the maintenance of the proinflammatory macrophage phenotype during injury. Administration of IL-6-neutralizing antibody in miR-223-3p-knockout muscle could rescue the impaired regeneration ability and reduce the fibrosis. Together, our results reveal that miR-223-3p improves muscle regeneration by regulating inflammation, indicating that miRNAs can participate in skeletal muscle regeneration by controlling the balance of pro- and anti-inflammatory factors in the skeletal muscle microenvironment.


Assuntos
MicroRNAs/biossíntese , Músculo Esquelético , Regeneração , Regulação para Cima , Animais , Inflamação/genética , Inflamação/metabolismo , Interleucina-6/biossíntese , Interleucina-6/genética , Camundongos , Camundongos Knockout , MicroRNAs/genética , Músculo Esquelético/lesões , Músculo Esquelético/fisiologia , RNA-Seq
9.
Sheng Li Xue Bao ; 73(4): 571-576, 2021 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-34405213

RESUMO

This study aims to explore the effects of arachidonic acid lipoxygenase metabolism in vascular calcification. We used 5/6 nephrectomy and high-phosphorus feeding to establish a model of vascular calcification in mice. Six weeks after nephrectomy surgery, vascular calcium content was measured, and Alizarin Red S and Von Kossa staining were applied to detect calcium deposition in aortic arch. Control aortas and calcified aortas were collected for mass spectrometry detection of arachidonic acid metabolites, and active molecules in lipoxygenase pathway were analyzed. Real-time quantitative PCR was used to detect changes in the expression of lipoxygenase in calcified aortas. Lipoxygenase inhibitor was used to clarify the effect of lipoxygenase metabolic pathways on vascular calcification. The results showed that 6 weeks after nephrectomy surgery, the aortic calcium content of the surgery group was significantly higher than that of the sham group (P < 0.05). Alizarin Red S staining and Von Kossa staining showed obvious calcium deposition in aortic arch from surgery group, indicating formation of vascular calcification. Nine arachidonic acid lipoxygenase metabolites were quantitated using liquid chromatography/mass spectrometry (LC-MS) analysis. The content of multiple metabolites (12-HETE, 11-HETE, 15-HETE, etc.) was significantly increased in calcified aortas, and the most abundant and up-regulated metabolite was 12-HETE. Furthermore, we examined the mRNA levels of metabolic enzymes that produce 12-HETE in calcified blood vessels and found the expression of arachidonate lipoxygenase-15 (Alox15) was increased. Blocking Alox15/12-HETE by Alox15 specific inhibitor PD146176 significantly decreased the plasma 12-HETE content, promoted calcium deposition in aortic arch and increased vascular calcium content. These results suggest that the metabolism of arachidonic acid lipoxygenase is activated in calcified aorta, and the Alox15/12-HETE signaling pathway may play a protective role in vascular calcification.


Assuntos
Ácidos Hidroxieicosatetraenoicos , Calcificação Vascular , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico , Animais , Araquidonato 12-Lipoxigenase , Araquidonato 15-Lipoxigenase/metabolismo , Ácido Araquidônico , Lipoxigenase/metabolismo , Camundongos , Transdução de Sinais
10.
Sheng Li Xue Bao ; 73(4): 577-583, 2021 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-34405214

RESUMO

The objective of this study was to explore the roles of arachidonic acid cytochrome P450ω hydroxylase CYP4A14 in skeletal muscle regeneration after injury. Wild-type (WT) control mice and Cyp4a14 knockout (A14-/-) mice were used to establish the muscle injury and regeneration model by intramuscular injection with cardiotoxin (CTX) on the tibial anterior (TA) muscle. The TA muscles were harvested at the time points of 0, 3, 5 and 15 days after injury. The changes in skeletal muscle regeneration and fibrosis were assessed by wheat germ agglutinin (WGA) staining and Sirius Red staining. Immunohistochemical staining was used to observe the expression of proliferation-related protein Ki-67 and macrophage marker protein Mac-2. The mRNA levels of regeneration and inflammation associated genes were analyzed by real-time PCR. The results showed that the cross-section area (CSA) of regenerated myofibers in A14-/- mice was significantly smaller (P < 0.05), while the percentage of fibrosis area was significantly higher than those in WT mice at 15 days after injury (P < 0.05). In A14-/- muscles, both the ratio of Ki-67 positive proliferating cells and the mRNA levels of differentiation associated genes Myod1 and Myog were significantly lower than those in WT muscles (P < 0.05). At 3 days after injury, the mRNA expression of inflammatory cells marker genes CD45 and CD11b and Mac-2 positive macrophages in A14-/- muscles were significantly lower than those in WT skeletal muscle (P < 0.05). Macrophages derived pro-regeneration cytokines IL-1ß, IGF-1 and SDF-1 were also significantly decreased in A14-/- muscles (P < 0.05). These results suggest that arachidonic acid cytochrome P450ω hydroxylase CYP4A14 plays a critical role in skeletal muscle regeneration after injury.


Assuntos
Oxigenases de Função Mista , Regeneração , Animais , Ácido Araquidônico , Citocromos , Técnicas de Inativação de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético
11.
Soft Matter ; 16(47): 10750-10758, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33107898

RESUMO

In this study, we investigate the conformational evolution and phase behavior of poly(acrylic acid) (PAA) solution upon the introduction of ferric ions through a combination of small angle X-ray scattering (SAXS), turbidity, zeta-potential and pH measurements. Salt-free PAA aqueous solution is a weak polyelectrolyte solution. The introduced ferric ion can coordinate with the carboxylic acid groups, yielding H+ ions to lower the pH value. We find two transitions with increasing concentration of the ferric ions: a polyelectrolyte to apparent good solution transition characterized by the disappearance of the polyelectrolyte peak in the X-ray scattering, and a phase separation characterized by a sharp increase of the turbidity. Detailed analyses of pH and zeta-potential reveal the molecular details of the three regions. Namely, (1) the polyelectrolyte region locates at log[H+] (= -pH) ≫ log(3[Fe3+]), where the H+ ions are mainly contributed from the dissociation of carboxylic acid, and the polymer chains are negatively charged, (2) the good solution region locates at log[H+] ∼ log(3[Fe3+]), where the H+ ions are mainly yielded from coordination between COO- and Fe3+, and polymer chains are nearly neutralized, and (3) the phase separation locates at log[H+] ≪ log(3[Fe3+]), where the Fe3+ ions are not fully coordinated, and charge inversion occurs. The phase separation occurs when the chains are densely and tightly coordinated with Fe3+ ions.

12.
Soft Matter ; 15(31): 6353-6361, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298682

RESUMO

A clear description of the conformational and dynamical evolution of polymer chains in shear flow is the fundamental basis of microfluidic separations and macroscopic rheological behaviors. We employ graph theory analysis to analyze the local deformation and dynamics of linear polymer chains with different rigidities in shear flow based on the simulation trajectories that record the instantaneous conformations and dynamics. Our results show that all semiflexible chains experience quasi-periodic tumbling motions when the shear strain overwhelms the U-shape (or S-shape) deformation energy barrier. More interestingly, the contact map provides solid evidence for the asymmetric deformation in the whole tumbling motion. In the stretching process: at small and intermediate shear strength, flexible polymers show a quasi-affine deformation while semiflexible ones are initially unfolded from the center of the chains, then both of them follow the extension with half dumbbell- or dumbbell-like ends; at high shear strength, all polymer chains present only a dumbbell-like extension. In the collapse process, all chains prefer to initiate the folding from chain ends. This finding can facilitate our understanding on how semiflexible polymer chains relax and dissipate the stress in shear flow.

13.
Soft Matter ; 14(18): 3455-3462, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29682643

RESUMO

Integrating natural macromolecules, e.g. proteins, is a progressive trend in the fabrication of biocompatible sub-micrometer fibers with tunable diameters using the electrospinning technique. The correlation between solution properties and electrospun morphology is critical; it is quite clear for synthetic linear polymer solutions but remains uncertain for solutions with protein. Here, we report the determination of electrospun morphology in protein-polymer solutions of poly(ethylene oxide) (PEO) and zein, a storage protein from corn. The viscosity of the zein/PEO mixed solutions can be well described using the Lederer-Roegiers equation and decreases with the increase of the fraction of zein. The surface tension sharply decreases above a critical concentration at the saturation of the interfacial monolayer. Correspondingly, the different electrospun morphologies-from bead, coexisting bead and fiber, to fiber and ribbon-were mapped onto a ternary phase diagram and a viscosity contour plot. Such coupling provides a clear way to determine the electrospun morphology from solution properties. The occurrence of electrospun fibers partially follows two empirical rules, while the critical point revealed from surface tension has the best approximation. The diameters of electrospun fibers were found to have a scaling relationship against concentration, zero-shear viscosity and surface tension of solutions. These scaling exponents were compared with those from typical polymer solutions. The analysis suggests that aqueous ethanol gives different solvent qualities to zein and PEO solutions, resulting in the irregular shape in the phase diagram that correlates solution properties and electrospun morphologies.


Assuntos
Eletricidade , Polietilenoglicóis/química , Zeína/química , Etanol/química , Soluções , Viscosidade , Água/química
14.
Clin Transplant ; 30(7): 845-51, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27146340

RESUMO

BACKGROUND: The burden of mast cell (MC) infiltration and their phenotypes, MC-tryptase (MCT ) and MC-tryptase/chymase (MCTC ), after lung transplantation (LT) has not been evaluated in human studies. METHODS: We reviewed 20 transbronchial lung biopsy (TBLB) specimen from patients with early normal allograft (<6 months post-LT, n=5), late normal allograft (>6 months, n=5), A2 or worse acute cellular rejection (ACR, n=5), and chronic lung allograft dysfunction (CLAD, n=5). Slides were immunostained for tryptase and chymase. Total MC, MCT , MCTC and MCTC to-MCT ratio were compared between the four groups using a generalized linear mixed model. RESULTS: Irrespective of clinicopathologic diagnosis, MC burden tends to increase with time (r(2) =.56, P=.009). MCTC phenotype was significantly increased in the CLAD group (8.2±4.9 cells per HPF) in comparison with the other three groups (early normal: 1.6±1.7, P=.0026; late normal: 2.5±2.3, P=.048; ACR: 2.7±3.5, P=.021). Further, the ratio of MCTC to MCT was significantly increased in CLAD group as compared to the other three groups (P<.001 for all comparisons). CONCLUSIONS: The burden of MC may increase in the allograft as function of time. Patients with CLAD have an increased relative and absolute burden of MCTC phenotype MC. Future studies are needed to confirm these findings and evaluate the potential pathologic role of MCTC in allograft dysfunction.


Assuntos
Transplante de Pulmão , Pulmão/patologia , Mastócitos/patologia , Idoso , Aloenxertos , Biópsia , Contagem de Células , Feminino , Humanos , Imunofenotipagem , Pulmão/cirurgia , Masculino , Mastócitos/enzimologia , Pessoa de Meia-Idade , Fenótipo , Período Pós-Operatório , Estudos Retrospectivos , Triptases/metabolismo
15.
Biochem Biophys Res Commun ; 462(4): 420-5, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25969427

RESUMO

Clinical and epidemiological investigations confirm that patients with loss-of-function mutations (R19X, etc.) in Apolipoprotein CIII (ApoCIII) showed beneficial lipid profile including decreased plasma triglyceride and increased high density lipoprotein (HDL) levels. However, whether HDL level would be reduced in hypertriglyceridemia (HTG) induced by high ApoCIII expression has not been demonstrated yet. Here we showed, ApoCIII transgenic mice (ApoCIIItg) displayed severe HTG and had significantly lower HDL level. Analysis of apolipoproteins in lipoprotein fractions by SDS-PAGE revealed marked decrease of apolipoprotein AI (ApoAI) in HDL in transgenic mice compared with the wild type mice (WT) as controls. Further examination demonstrated that hepatic but not intestinal ApoAI mRNA was significantly reduced. Therefore, the decreased ApoAI synthesis might be accounted for the lower plasma HDL level in ApoCIII transgenic mice.


Assuntos
Apolipoproteína A-I/biossíntese , Apolipoproteína C-III/sangue , HDL-Colesterol/sangue , Hipertrigliceridemia/prevenção & controle , Animais , Apolipoproteína C-III/biossíntese , Apolipoproteína C-III/genética , Sequência de Bases , Primers do DNA , Hipertrigliceridemia/sangue , Fígado/metabolismo , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real
16.
Biochem Biophys Res Commun ; 461(2): 206-10, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25866184

RESUMO

Congenital generalized lipodystrophy (CGL) is characterized by a complete loss of body adipose tissue accompanying dyslipidemia, severe hepatic steatosis and insulin resistance. However, the mechanisms of dyslipidemia and hepatic steatosis are unclear. Here using the lipodystrophic Seipin-deficient mouse (Seipin(-/-)) model, we found Seipin(-/-) mice were unable to respond appropriately to a long time fasting and developed postprandial hypertriglyceridemia. Impaired very low density lipoprotein (VLDL) secretion and enhanced triglyceride-rich lipoproteins (TRL) clearance were also observed in our Seipin(-/-) mice. To identify the association between upregulation of hepatic LDL receptor and enhanced TRL clearance, we crossed Seipin(-/-) mice with Ldlr(-/-) mice to generate Seipin(-/-)Ldlr(-/-) mice. Seipin(-/-)Ldlr(-/-) mice displayed increased TRL clearance only after 24 h-fast rather 6 h-fast. In contrast to Seipin(-/-) mice, Seipin(-/-)Ldlr(-/-) mice displayed hypertriglyceridemia as observed in human CGL patients. Furthermore, in this study, we demonstrated hepatic steatosis in lipodystrophy Seipin(-/-) mice is a metabolic adaptation of dysfunctional adipose tissue. This study using lipodystrophic model established the importance of adipose tissue in energy homeostasis and lipid metabolism.


Assuntos
Proteínas Heterotriméricas de Ligação ao GTP/genética , Metabolismo dos Lipídeos , Lipodistrofia/genética , Lipodistrofia/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Jejum , Subunidades gama da Proteína de Ligação ao GTP , Deleção de Genes , Hiperglicemia/etiologia , Hiperglicemia/genética , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Lipodistrofia/complicações , Lipodistrofia/patologia , Lipodistrofia Generalizada Congênita/complicações , Lipodistrofia Generalizada Congênita/genética , Lipodistrofia Generalizada Congênita/metabolismo , Lipodistrofia Generalizada Congênita/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
17.
J Exp Bot ; 66(9): 2723-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25769309

RESUMO

Breeding for strong root systems is an important strategy for improving drought avoidance in rice. To clone genes responsible for strong root traits, an upland rice introgression line IL392 with thicker and longer roots than the background parent lowland rice Yuefu was selected. A quantitative trait locus (QTL), qRT9, controlling root thickness and root length was detected under hydroponic culture using 203 F(2:3) populations derived from a cross between Yuefu and IL392. The qRT9 locus explained 32.5% and 28.1% of the variance for root thickness and root length, respectively. Using 3185 F2 plants, qRT9 was ultimately narrowed down to an 11.5 kb region by substitution mapping. One putative basic helix-loop-helix (bHLH) transcription factor gene, LOC_Os09g28210 (named OsbHLH120), is annotated in this region. Sequences of OsbHLH120 in 11 upland rice and 13 lowland rice indicated that a single nucleotide polymorphism (SNP) at position 82 and an insertion/deletion (Indel) at position 628-642 cause amino acid changes and are conserved between upland rice and lowland rice. Phenotypic analysis indicated that the two polymorphisms were significantly associated with root thickness and root length under hydroponic culture. Quantitative real-time PCR showed that OsbHLH120 was strongly induced by polyethylene glycol (PEG), salt, and abscisic acid, but higher expression was present in IL392 roots than in Yuefu under PEG and salt stress. The successfully isolated locus, qRT9, enriches our knowledge of the genetic basis for drought avoidance and provides an opportunity for breeding drought avoidance varieties by utilizing valuable genes in the upland rice germplasm.


Assuntos
Oryza/genética , Locos de Características Quantitativas , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Estudos de Associação Genética , Dados de Sequência Molecular , Oryza/anatomia & histologia , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Melhoramento Vegetal , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Estresse Fisiológico
18.
Mol Pharm ; 12(3): 665-74, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25587935

RESUMO

Probucol (PB), an antioxidant drug, is commonly used as a lipid concentration lowering drug to reduce blood plasma cholesterol levels in the clinic. However, the therapeutic effects of this drug are negatively impacted by its poor water solubility and low oral absorption efficiency. In this study, a PEGylated G5 PAMAM dendrimer (G5-PEG) modified nanoliposome was employed to increase water solubility, transepithelial transport, and oral absorption of PB. The uptake mechanism was explored in vitro in Caco-2 cells with the results suggesting that the absorption improvement of G5-PEG modified PB-liposome (PB-liposome/G5-PEG) was related to P-glycoprotein (P-gp) efflux pump but was independent of caveolae endocytosis pathways. Additionally, plasma lipid concentration lowering effects of PB-liposome/G5-PEG were evaluated in vivo in a LDLR-/- hyperlipidemia mouse model. Compared with saline treated group, treatment with PB-liposome/G5-PEG significantly inhibited the increase of plasma total cholesterol (TC) and triglyceride (TG) of mice induced by a high fat diet. Moreover, its lipid concentration lowering effects and plasma drug concentration were greater than PB alone or commercial PB tablets. Our results demonstrated that PB-liposome/G5-PEG significantly increased the oral absorption of PB and therefore significantly improved its pharmacodynamic effects.


Assuntos
Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/farmacocinética , Sistemas de Liberação de Medicamentos , Lipossomos , Nanocápsulas , Probucol/administração & dosagem , Probucol/farmacocinética , Administração Oral , Animais , Células CACO-2 , Colesterol/sangue , Dendrímeros/química , Estabilidade de Medicamentos , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Absorção Intestinal , Lipossomos/química , Masculino , Camundongos , Camundongos Knockout , Nanocápsulas/química , Polietilenoglicóis/química , Receptores de LDL/deficiência , Receptores de LDL/genética , Solubilidade , Triglicerídeos/sangue
19.
Biomacromolecules ; 16(1): 174-82, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25479110

RESUMO

In this study, generation 5 (G5) polyamidoamine (PAMAM) dendrimers with two different surface groups, G4.5-COOH and G5-OH, were investigated for their protective effects on pancreas injury in a caerulein-induced acute pancreatitis (AP) mouse model. Both dendrimers significantly decreased pathological changes in the pancreas and reduced the inflammatory infiltration of macrophages in pancreatic tissues. In addition, the expression of pro-inflammatory cytokines was significantly inhibited by the two dendrimers, not only in pancreatic tissues from AP mice but also in vitro in mouse peritoneal macrophages with LPS-induced inflammation. G4.5-COOH, which had better in vivo protective effects for AP than G5-OH, led to a significant reduction in the total number of plasma white blood cells (WBCs) and monocytes in AP mice, and its anti-inflammatory mechanism was related to inhibition of the nuclear translocation of NF-κB in macrophages.


Assuntos
Ceruletídeo/toxicidade , Dendrímeros/administração & dosagem , Pancreatite/prevenção & controle , Substâncias Protetoras/administração & dosagem , Animais , Dendrímeros/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/sangue , Pancreatite/sangue , Pancreatite/patologia , Substâncias Protetoras/química
20.
J Vasc Res ; 51(5): 369-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25531767

RESUMO

BACKGROUND/AIMS: Late-outgrowth CD45-negative endothelial colony-forming cells are implicated to be circulating endothelial progenitor cells (EPCs), as they express endothelial cell markers and can directly form blood vessels. As these cells share characteristics of other progenitor cell phenotypes, late-outgrowth EPCs were assayed for both multilineage differentiation capability and for markers of pluripotency. METHODS: Clonal single-colony late-outgrowth EPCs were derived from human cord blood and assayed both for multilineage differentiation capability in vitro and for markers of pluripotency by qPCR. RESULTS: Under osteogenic growth conditions, these EPCs expressed the osteogenic markers RUNX2, COL1A1, ALPL, and osteocalcin and demonstrated calcium deposition and bone mineralization. Endothelial colony-forming cells expressed markers associated with induced pluripotent stem cells, including SOX2, POU5F1, c-MYC, and KLF4. CONCLUSIONS: Late-outgrowth EPCs express markers associated with pluripotency and can directly express an osteogenic phenotype under bone differentiation conditions in vitro.


Assuntos
Diferenciação Celular , Células Progenitoras Endoteliais/metabolismo , Sangue Fetal/citologia , Antígenos Comuns de Leucócito/deficiência , Células-Tronco Multipotentes/metabolismo , Osteogênese , Células-Tronco Pluripotentes/metabolismo , Biomarcadores/metabolismo , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Células Progenitoras Endoteliais/imunologia , Humanos , Fator 4 Semelhante a Kruppel , Células-Tronco Multipotentes/imunologia , Fenótipo , Células-Tronco Pluripotentes/imunologia , Fatores de Tempo
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