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1.
Artigo em Inglês | MEDLINE | ID: mdl-32324368

RESUMO

Mesoporous aluminosilicates are promising solid acid catalysts. They are also excellent supports for transition metal catalysts for various catalytic applications. Synthesis of mesoporous aluminosilicates with controllable particle size, morphology, and structure, as well as adjustable acidity and high hydrothermal stability, is very desirable. In this work, we demonstrate the scalable synthesis of Al-SBA-15 microspheres with controllable physicochemical properties by using the microfluidic jet-spray-drying technology. The productivity is up to ∼30 g of dried particles per nozzle per hour. The Al-SBA-15 microspheres possess uniform controllable micron sizes (27.5-70.2 µm), variable surface morphologies, excellent hydrothermal stability (in pure steam at 800 °C), high surface areas (385-464 m2/g), ordered mesopore sizes (5.4-5.8 nm), and desirable acid properties. The dependence of various properties, including particle size, morphology, porosity, pore size, acidity, and hydrothermal stability, of the obtained Al-SBA-15 microspheres on experimental parameters including precursor composition (Si/Al ratio and solid content) and processing conditions (drying and calcination temperatures) is established. A unique morphology transition from smooth to wrinkled microsphere triggered by control of the Si/Al ratio and solid content is observed. The particle formation and morphology-evolution mechanism are discussed. The Al-SBA-15 microspheres exhibit high acid catalytic performance for aldol-condensation reaction between benzaldehyde and ethyl alcohol with a high benzaldehyde conversion (∼56.3%), a fast pseudo-first-order reaction rate (∼0.1344 h-1), and a high cyclic stability, superior to the commercial zeolite acid (H-ZSM-5). Several influencing factors on the catalytic performance of the obtained Al-SBA-15 microspheres are also studied.

4.
FASEB J ; 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32307751

RESUMO

Islet transplantation in man is limited by multiple factors including islet availability, islet cell damage caused by collagenase during isolation, maintenance of islet function between isolation and transplantation, and allograft rejection. In this study, we describe a new approach for preparing islets that enhances islet function in vitro and reduces immunogenicity. The approach involves culture on native decellularized 3D bone marrow-derived extracellular matrix (3D-ECM), which contains many of the matrix components present in pancreas, prior to islet transplantation. Compared to islets cultured on tissue culture plastic (TCP), islets cultured on 3D-ECM exhibited greater attachment, higher survival rate, increased insulin content, and enhanced glucose-stimulated insulin secretion. In addition, culture of islets on 3D-ECM promoted recovery of vascular endothelial cells within the islets and restored basement membrane-related proteins (eg, fibronectin and collagen type VI). More interestingly, culture on 3D-ECM also selectively decontaminated islets of "passenger" cells (co-isolated with the islets) and restored basement membrane-associated type VI collagen, which were associated with an attenuation in islet immunogenicity. These results demonstrate that this novel approach has promise for overcoming two major issues in human islet transplantation: (a) poor yield of islets from donated pancreas tissue and (b) the need for life-long immunosuppression.

5.
Clin Cancer Res ; 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32234760

RESUMO

PURPOSE: Adults with T-cell lymphoblastic lymphoma (T-LBL) generally benefit from treatment with acute lymphoblastic leukemia (ALL)-like regimens, but approximately 40% will relapse after such treatment. We evaluated the value of CpG methylation in predicting relapse for adults with T-LBL treated with ALL-like regimens. EXPERIMENTAL DESIGN: A total of 549 adults with T-LBL from 27 medical centers were included in the analysis. Using the Illumina Methylation 850K Beadchip, 44 relapse-related CpGs were identified from 49 T-LBL samples by two algorithms: least absolute shrinkage and selector operation (LASSO) and support vector machine-recursive feature elimination (SVM-RFE). We built a four-CpG classifier using LASSO Cox regression based on association between the methylation level of CpGs and relapse-free survival in the training cohort (n = 160). The four-CpG classifier was validated in the internal testing cohort (n = 68) and independent validation cohort (n = 321). RESULTS: The four-CpG-based classifier discriminated patients with T-LBL at high risk of relapse in the training cohort from those at low risk (P < 0.001). This classifier also showed good predictive value in the internal testing cohort (P < 0.001) and the independent validation cohort (P < 0.001). A nomogram incorporating five independent prognostic factors including the CpG-based classifier, lactate dehydrogenase levels, Eastern Cooperative Oncology Group performance status, central nervous system involvement, and NOTCH1/FBXW7 status showed a significantly higher predictive accuracy than each single variable. Stratification into different subgroups by the nomogram helped identify the subset of patients who most benefited from more intensive chemotherapy and/or sequential hematopoietic stem cell transplantation. CONCLUSIONS: Our four-CpG-based classifier could predict disease relapse in patients with T-LBL, and could be used to guide treatment decision.

7.
Tissue Eng Part A ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32164476

RESUMO

Nerve tissue regeneration continues to represent an intractable obstacle to realizing the promise of tissue engineering. While neurobiology works to shed light on the mechanisms governing neuronal growth and repair, considerable technical gaps remain that hinder progress. Chief among these is the absence of an appropriate culture environment to faithfully reproduce the neuronal niche ex vivo. We propose that the various multipotent cells found in the oral cavity may represent an important, yet underutilized resource for preparing such neurogenic microenvironments. Like those of nerve tissue, these cell populations are of ectodermal origin and have clinically demonstrated neurogenic potential. While there is a lack of consensus on whether putative types of oral and craniofacial stem cells constitute distinct populations, their contribution to neural tissue engineering may be two-fold: as a cellular feedstock for neoneurogenesis and for the production of specialized in vitro environments for neurogenic differentiation, phenotype maintenance, and use in therapeutic applications.

8.
Biotechniques ; 68(5): 257-262, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32090587

RESUMO

Extracellular vesicles (EVs) are small membranous particles that contribute to intercellular communications. Separating EVs from tissue is still a technical challenge. Here, we present a rigorous method for extracting EVs from intestinal tissue in a mouse intestinal ischemia/reperfusion (I/R) model, and for analyzing their miRNA content. The isolated EVs show a typical cup shape with a size peak of 120-130 nm in diameter, confirmed by TEM and NTA. They also express EV markers such as CD9, CD63, CD81, Tsg101 and Alix. Real-time qPCR confirmed that these pellets contain miRNAs related to I/R injury. Our study presents a practical way to isolate EVs from intestinal tissue which is suitable for downstream applications such as miRNA analysis, and provides a novel method for investigating the mechanism of intestinal I/R injury.

9.
Environ Sci Technol ; 54(6): 3714-3724, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32069034

RESUMO

Bimetallic Fe-Mn oxide (BFMO) has been regarded as a promising activator of peroxysulfate (PS), the sustained activity and durability of BFMO for long-term activation of PS in situ, however, is unclear for groundwater remediation. A BFMO (i.e., Mn1.5FeO6.35) was prepared and explored for PS-based in situ chemical oxidation (ISCO) of trichloroethylene (TCE) in sand columns with simulated/actual groundwater (SGW/AGW). The sustained activity of BFMO, oxidant utilization efficiency, and postreaction characterization were particularly investigated. Electron spin resonance (ESR) and radical scavenging tests implied that sulfate radicals (SO4•-) and hydroxyl radicals (HO•) played major roles in degrading TCE, whereas singlet oxygen (1O2) contributed less to TCE degradation by BFMO-activated Oxone. Fast degradation and almost complete dechlorination of TCE in AGW were obtained, with reaction stoichiometry efficiencies (RSE) of ΔTCE/ΔOxone at 3-5%, much higher than those reported RSE values in H2O2-based ISCO (≤0.28%). HCO3- did not show detrimental effect on TCE degradation, and effects of natural organic matters (NOM) were negligible at high Oxone dosage. Postreaction characterizations displayed that the BFMO was remarkably stable with sustained activity for Oxone activation after 115 days of continuous-flow test, which therefore can be promising catalyst for Oxone-based ISCO for TCE-contaminated groundwater remediation.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Peróxido de Hidrogênio , Oxirredução , Óxidos , Ácidos Sulfúricos
10.
Leukemia ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080345

RESUMO

We aimed to establish a discriminative gene-expression-based classifier to predict survival outcomes of T-cell lymphoblastic lymphoma (T-LBL) patients. After exploring global gene-expression profiles of progressive (n = 22) vs. progression-free (n = 28) T-LBL patients, 43 differentially expressed mRNAs were identified. Then an eleven-gene-based classifier was established using LASSO Cox regression based on NanoString quantification. In the training cohort (n = 169), high-risk patients stratified using the classifier had significantly lower progression-free survival (PFS: hazards ratio 4.123, 95% CI 2.565-6.628; p < 0.001), disease-free survival (DFS: HR 3.148, 95% CI 1.857-5.339; p < 0.001), and overall survival (OS: HR 3.790, 95% CI 2.237-6.423; p < 0.001) compared with low-risk patients. The prognostic accuracy of the classifier was validated in the internal testing (n = 84) and independent validation cohorts (n = 360). A prognostic nomogram consisting of five independent variables including the classifier, lactate dehydrogenase levels, ECOG-PS, central nervous system involvement, and NOTCH1/FBXW7 status showed significantly greater prognostic accuracy than each single variable alone. The addition of a five-miRNA-based signature further enhanced the accuracy of this nomogram. Furthermore, patients with a nomogram score ≥154.2 significantly benefited from the BFM protocol. In conclusion, our nomogram comprising the 11-gene-based classifier may make contributions to individual prognosis prediction and treatment decision-making.

11.
Food Funct ; 11(1): 211-220, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31915766

RESUMO

Evolution of important glucosinolates (GLSs), namely, sinigrin, glucoraphanin, glucoerucin and glucobrassicin, in three commonly consumed Brassica vegetables viz. white cabbage, Chinese cabbage and bok choy during their processing into vegetable powder was investigated. Drying was noted to be a major processing step causing significant losses of GLSs. Interestingly, different GLSs and even the same GLSs in different vegetables showed different thermal stabilities during drying. The stability of GLSs in vegetable powder during in vitro gastric digestion was also studied. Glucoraphanin exhibited the highest stability while glucobrassicin was the most vulnerable GLS under in vitro gastric conditions. White cabbage is found to be a promising material for the production of vegetable powder as it contains high contents of GLSs, especially glucoraphanin and glucoerucin, which are important precursors of anticarcinogenic compounds, namely sulforaphane and erucin. These two GLSs were also noted to be stable during in vitro gastric digestion.

12.
Food Funct ; 11(2): 1892, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31994585

RESUMO

Correction for 'Evolution of important glucosinolates in three common Brassica vegetables during their processing into vegetable powder and in vitro gastric digestion' by Thitima Kuljarachanan et al., Food Funct., 2020, DOI: 10.1039/c9fo00811j.

13.
J Agric Food Chem ; 68(2): 574-583, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31820633

RESUMO

Food structure is a key determinant for the release of phenolic compounds during gastric and intestinal digestion. We evaluated the bioaccessibility of polyphenols from apple tissue during gastric digestion in vitro from bio-mechanical perspectives including the effects of gastric juice and mucin on the apple tissue matrix under simulated stomach peristalsis. The gastric model system was effective in releasing polyphenols because of simultaneous compression and extrusion, with 3 times higher release from coarse than from fine particles. However, bioaccessibility of polyphenols was reduced up to 44% in the presence of both cell walls and gastric mucin. Most individual phenolic molecules were gradually released and were stable in the gastric environment, except for procyanidin B2. The study suggests that the bioaccessibility of polyphenols from apples in the upper digestive tract is dependent on mechanical disintegration and the residual matrix present in the swallowed bolus.


Assuntos
Digestão , Malus/metabolismo , Polifenóis/metabolismo , Estômago/fisiologia , Disponibilidade Biológica , Parede Celular/química , Parede Celular/metabolismo , Frutas/química , Frutas/metabolismo , Humanos , Malus/química , Modelos Biológicos , Polifenóis/química
14.
Colloids Surf B Biointerfaces ; 185: 110629, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734090

RESUMO

The purpose of this study was to create W1/O/W2 Multiple Emulsions by controlled osmotic swelling, and gelation of whey protein isolate (WPI) and high methoxy pectin (HMP) microspheres in internal and external acidic aqueous phases. Three different kinds of W1/O/W2 multiple emulsions (ME) were prepared, with 8 wt.% Polyglycerol polyricinoleate (PGPR) in their oil phases, with WPI and HMP in internal and external aqueous phases (250 mM NaCl, pH 3.5): (i) ME1: The inner aqueous phase (W1) contained 40% buffer solution, while W2 consisted of 10% WPI and 2% HMP; (ii) ME2: W1 contained 10% WPI, with 2% HMP (250 mM NaCl) in W2; (iii) ME3: 10% WPI and 2% HMP in W1, while W2 contained 1% Tween 80. The original multiple emulsions were diluted by different factors (1:0 to 1:5 with citrate buffer solution), and subject to thermal treatment from 25 to 90 °C to compare their microstructural and rheological properties. It was observed that the ME1 emulsion had higher viscosity and shear modulus than for other emulsions. After dilution however, the shear viscosity of ME3 was higher than ME1 and ME 2 at intermediate shear rates, which showed that the emulsions were osmotically well controlled in internal aqueous phases. Optical and confocal microscopy also supported our rheological measurements with evidence of WPI-HMP gelation, and osmotic swelling, in original and in swollen multiple emulsions. The results of this work may provide useful information about the encapsulation of bioactive compounds, in internal and external aqueous phases, for the development of healthier reduced-fat products in food industry.

15.
ACS Appl Mater Interfaces ; 12(4): 4769-4776, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31886642

RESUMO

High desalination efficiency in principle could be achieved by layer-by-layer graphene oxide (GO) membranes, which benefits from their entrance-functionalized channels assembled by edge-functionalized GO nanosheets. The effects of these edge functional groups on desalination, however, are not fully understood yet. To study the isolated influence of three typical edge functional groups, namely, carboxyl (-COOH), hydroxyl (-OH), and hydrogen (-H), molecular dynamics simulation was used in this work. The results revealed that the edge volumetric blockage effect, resulting in ion permeability at G-H > G-OH > G-COOH membranes, was the dominant mechanistic effect inside the GO membranes with 7 Å interlayer channels. The OH edge has the same effect as the H edge in NaCl/water selectivity because of a unique "ion pulling" effect. Moreover, the OH and H edge-functionalized membranes with 7 Å interlayer channels showed preferential Na+ and Cl- rejections, respectively. This kind of preference leads to a cycle of charging and neutralization in the penetrant reservoir throughout the filtration process. The results from this work suggested that it would be strategic to keep the COOH and H edge functional groups, to maintain the size of interlayer channels in order to stimulate the effects of edge functional groups, and to increase the membrane porosity for designing higher desalination efficiency GO membranes.

16.
Burns ; 46(1): 182-189, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31859083

RESUMO

BACKGROUND: Many studies have suggested that procalcitonin can predict bloodstream infection and also distinguish between Gram-negative, Gram-positive and fungal infections after burn. However, up to now, there is no literature on serum procalcitonin level of multidrug-resistant pathogens and non-multidrug-resistant pathogens among Gram-negative bloodstream infections after burn. The purpose of this study is to explore the value of serum procalcitonin in identifying Gram-negative bloodstream infection in patients with febrile critical burn and then to investigate the difference of serum procalcitonin level between multidrug-resistant pathogens and non-multidrug-resistant pathogens among Gram-negative bloodstream infections after burn. METHODS: Patients with febrile critical burn admitted to the burn department of our hospital from 1 January 2014 to 1 August 2018 were retrospectively analysed. Patients with positive blood culture whose blood samples were collected for simultaneous blood culture and procalcitonin testing were enrolled. All strains were identified by an automatic microorganism analyser, and procalcitonin was analysed by an automatic electrochemiluminescence immunoassay. RESULTS: Overall, a total of 119 patients with positive blood culture met the inclusion criteria. There were 64 Gram-negative bacilli, 38 Gram-positive bacteria, 8 C. albicans and 9 polymicrobial bloodstream infections. The median procalcitonin value in Gram-negative bloodstream infections (2.67 ng/mL, interquartile range (IQR) 1.58-6.08) was significantly higher than that in Gram-positive bloodstream infections (1.04 ng/mL, IQR 0.35-1.60, P < 0.01), or C. albicans bloodstream infections (1.09 ng/mL, IQR 0.82-2.30, P < 0.05). Receiver operating characteristic curve (ROC) analysis showed that in addition to polymicrobial bloodstream infections, the area of procalcitonin under the curve distinguishing Gram-negative bloodstream infections from all other blood culture-positive bloodstream infections was 0.761, the best critical value was 1.73 ng/mL, the sensitivity was 73%, the specificity was 74%, the positive predictive value was 80%, the negative predictive value was 67%, The level of procalcitonin was significantly higher in multidrug-resistant Gram-negative bacilli (A. baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa) (2.76 ng/mL, IQR 2.01-7.76) than in non-multidrug-resistant bacilli (1.01 ng/mL, IQR 0.58-1.56, P < 0.01). CONCLUSION: Elevated serum procalcitonin can identify Gram-negative bloodstream infections in patients with febrile critical burn. In Gram-negative bloodstream infections, high procalcitonin levels may be associated with multidrug-resistant Gram-negative bacilli (A. baumannii, K. pneumoniae and P. aeruginosa).

17.
J Asian Nat Prod Res ; : 1-7, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805779

RESUMO

A phytochemical investigation on the 90% ethanol aqueous extract of the aerial part of Kopsia arborea led to the isolation of three new monoterpenoid indole alkaloids, kopsiarborines A-C (1-3). The new structures were elucidated by using spectroscopic data (NMR, IR, UV, and MS). The isolated alkaloids were tested in vitro for cytotoxic potentials against six human lung cancer cell lines (A549, ATCC, H446, H460, H292, and 95-D). As a result, alkaloids 1 and 2 exhibited significant cytotoxic activities against all the tested tumor cell lines with IC50 values less than 20 µM.

18.
Sci Total Environ ; 688: 513-520, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726571

RESUMO

Ferric-nitrilotriacetate complex (FeIII-NTA) has been adopted to catalyze the photo-Fenton degradation of emerging pharmaceutical micropollutants in water and wastewater at neutral pH. The generation of hydroxyl radicals (HO) in UVA/FeIII-NTA/H2O2 was identified by using electron spin resonance (ESR) trapping technique. The effects of critical parameters (e.g., NTA:FeIII molar ratio, FeIII-NTA and H2O2 dosages) on the steady-state HO concentrations were studied in terms of the degradation of carbamazepine (CBZ, as a model compound) in Milli-Q water. In addition, the degradation of pharmaceuticals mixtures (including CBZ, crotamiton (CRMT) and ibuprofen (IBP)) in wastewater effluents from a biological aerated filter (BAF) by UVA/FeIII-NTA/H2O2 was studied in continuous-flow mode. The results showed that the efficacies of FeIII-NTA in catalyzing photo-Fenton degradation of pharmaceuticals in wastewater effluents were comparable to those obtained by FeIII-ethylenediamine-N,N'-disuccinic acid (FeIII-EDDS), and far exceeded other FeIII-L complex (e.g., citric acid, malonic acid, oxalic acid and tartaric acid). More than 92% degradation efficiencies of CBZ, CRMT and IBP were obtained in continuous-flow mode under the given conditions of 0.178 mM FeIII-NTA (1:1), 4.54 mM H2O2, UVA intensity 4.05 mW cm-2, hydraulic retention time (HRT) 2 h, influent pH 7.6 (±0.2) and temperature 20 °C. The results presented herein suggest that FeIII-NTA-catalyzed neutral photo-Fenton reaction can be an alternative tertiary process for the treatment of pharmaceutical micropollutants in secondary wastewater effluents.

19.
J R Soc Interface ; 16(159): 20190425, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31594526

RESUMO

Bionics is a fascinating subject that has inspired many inventions through learning from biological structures and functions. In this work, a coupled multi-physics model has been developed to characterize ocular water evaporation with realistic eyelash structures taken into account. From a chemical engineering perspective, the protective function of human eyelashes in terms of evaporation inhibition has been rationally revealed. Systematic investigations were carried out to elucidate the effects of different eyelash lengths, orientations and inlet air directions on water evaporation on the ocular surface. The results clearly demonstrate that regardless of inlet air directions and eyelash orientations, increasing eyelash length from zero to an optimal length can effectively reduce water evaporation. However, further increase in the eyelash length can lead to enhanced evaporation. For the normal and parallel inlet air directions, the optimal eyelash length is around 15-30% of the eye width and can offer approximately 10-30% evaporation reduction when compared with the cases without eyelashes. These values are independent of the eyelash orientation. This investigation provides valuable data for in-depth understanding of the protective function of the eyelashes, which can be used in the future to improve and optimize bionic designs inspired by human eyelashes.

20.
Photodiagnosis Photodyn Ther ; 28: 343-345, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31614224

RESUMO

Hidradenitis suppurativa (HS) is a type of chronic suppurative inflammatory reaction of the hair follicles characterized by recurrent dermal abscesses, sinus tracts and scars. In this report, one case of severe hypertrophic scar induced by facial HS achieved resolution of skin lesions after combined treatment with high concentration single-dose 5-aminolevulinic acid photodynamic therapy (5-ALA PDT). No recurrence was observed up to eleven months of follow-up. The 5-ALA PDT based treatment could improve the severe hypertrophic scar induced by HS in an effective and safe manner.

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