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1.
Int J Biol Macromol ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476399

RESUMO

The physical mechanics and structural properties of composite films based on chitosan and syringic acid (SA) were studied in this study. The results indicated that the addition of SA made the chitosan-SA films exhibited higher density, water solubility and opacity, but the water vapor permeability and water content were decreased. In addition, Chitosan-SA films had a significant antibacterial effect on test bacteria. The surface and cross-section of chitosan-SA films were more uniform and smoother when combined with 0.25% and 0.5% 0f SA. The FT-IR and XRD spectra of the chitosan-SA film indicated that the interaction between chitosan and SA may be non-covalent, and DSC indicated that the thermal stability of the composite film was reduced. In summary, the modified color, increased bacteriostatic and water-blocking properties, as well as the slight changes in mechanical properties indicated that the addition of SA may contribute to extend the shelf life of the food. Thus, chitosan-SA films incorporating 0.25% and 0.5% of SA can be further explored as active packing materials for food preservation. The composite film was used for the preservation of quail egg coatings, and it was found that 0.25% and 0.5% of the coating film had a good preservation effect.

2.
Mol Med Rep ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31485663

RESUMO

Polygonatum sibiricum polysaccharide (PSP) has been shown to alleviate hyperglycemia and reduce oxidative stress to delay the progression of diabetic retinopathy and cataracts. However, its role and underlying mechanisms in regulating type 2 diabetes mellitus (T2DM) remain unclear. Nuclear factor erythroid 2­related factor 2 (Nrf2) activation plays a protective role in T2DM. The present study focused on the effect of PSP on inflammatory cytokine secretion and Nrf2 expression in the adipocytes of T2DM patients. In this study, high­glucose­ and high­insulin­induced 3T3­L1 adipocytes were used to mimic insulin­resistant (IR)­3T3­L1 adipocytes. Furthermore, the effect and underlying mechanisms of PSP on inflammation and glucose uptake in IR­3T3­L1 adipocytes were investigated. The present study found that proliferation after 50, 100 and 250 µg/ml PSP treatment had no significant change in normal 3T3­L1 adipocytes. A total of 50, 100 and 250 µg/ml of PSP also alleviated IL­1ß, IL­6, and TNF­α levels and promoted proliferation, glucose uptake, and glucose transporter 4 expression in IR­3T3­L1 adipocytes. Furthermore, 50, 100 and 250 µg/ml PSP promoted Nrf2 and HO­1 expression. However, silencing Nrf2 expression reversed the effect of 100 µg/ml PSP in IR­3T3­L1 adipocytes. In conclusion, these results suggest that PSP alleviates inflammatory cytokines and promotes glucose uptake in IR­3T3­L1 adipocytes by promoting Nrf2 expression. PSP may be a potential therapeutic agent for T2DM treatment by promoting Nrf2 expression.

3.
Theranostics ; 9(16): 4633-4647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367246

RESUMO

Rationale: Mesenchymal stem cells (MSCs) have been demonstrated to ameliorate inflammatory bowel disease by their actions on multiple immune cells, especially on regulatory B cells (Breg cells). However, the phenotypes and functions of human MSCs (hMSCs)-treated Breg cell subsets are not yet clear. Methods: Purified B cells were cocultured with MSCs and the phenotypes and immunomodulatory functions of the B cells were analyzed by FACS and proliferation assays in vitro. Also, a trinitrobenzenesulfonic acid-induced mouse colitis model was employed to detect the function of MSC-treated Breg cells in vivo. Results: We demonstrated that coculturing with hMSCs significantly enhanced the immunomodulatory activity of B cells by up-regulating IL-10 expression. We then identified that a novel regulatory B cell population characterized by CD23 and CD43 phenotypic markers could be induced by hMSCs. The CD23+CD43+ Breg cells substantially inhibited the inflammatory cytokine secretion and proliferation of T cells through an IL-10-dependent pathway. More significantly, intraperitoneal injection of hMSCs ameliorated the clinical and histopathological severity in the mouse experimental colitis model, accompanied by an increase in the number of CD23+CD43+ Breg cells. The adoptive transfer of CD23+CD43+ B cells effectively alleviated murine colitis, as compared with the CD23-CD43- B cells. Treatment with CD23+CD43+ B cells, and not hMSCs, substantially improved the symptoms of colitis in B cell-depleted mice. Conclusion: the novel CD23+CD43+ Breg cell subset appears to be involved in the immunomodulatory function of hMSCs and sheds new light on elucidating the therapeutic mechanism of hMSCs for the treatment of inflammation-related diseases.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31434262

RESUMO

A total of 116 dust samples in downtown within the city wall were collected, and the spatial occurrence, source and health risk status of 19 trace metal/metalloids bound in street dusts (SDs) were systematically investigated. Geochemical maps, associations, risk models and indices were calculated to define levels of distribution, possible natural or anthropogenic sources, ecological and human health risks. It was found that the wide variations of these 19 trace metals would be observed in spatial maps, which indicated strongly anthropogenic activities inputs. Compared to the calculations of the potential ecological risk index of toxic trace metals, Pb (Eri = 20.32) ranked at the level of considerable ecological risk. The non-carcinogenic and carcinogenic risk from most trace metals exposed to children and adults were no significant health risks, except for the non-carcinogenic risk of Cr and As to children, and the carcinogenic risk of Cr to adults. The unacceptable risk locations were observed at traffic conjunctions, which should be given attention. The source apportionment results indicated that the trace metals/metalloids Co, Ga, Nb, As, Ni, and Y, coupled with main elements Al, K, Mg, Ca and Si, would possibly originate from "Soil Re-suspension", whereas Fe, Cu, Rb, La, Ba, Mn, Ti, Ce and Zr were possibly derived from "Brake Wear". As regards the Na, no valid assumption was formulated about the presence of this element in brake wear, while Cr, Sr, Zn were possibly associated with "Tire Wear". Comparatively, V would be suggested as a representative source of fuel consumption, and Pb could possibly belong to "Traffic Pigment". It was noted that the barbican city, surrounded by the Xi'an Ancient City Wall at 12 m high, would trap the trace metal emissions, and consequently increase the health risk for local residents.

5.
JCI Insight ; 4(16)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31434801

RESUMO

BACKGROUNDCytokine biomarkers have already been used to predict acute graft-versus-host disease (aGVHD) onset, nonrelapse mortality, and overall survival in human and mouse models, but the consistency of the consequences between patients and mice has not been evaluated. Furthermore, no study about any biomarker or biomarker panel for aGVHD grading or steroid sensitivity of aGVHD patients simultaneously has been reported.METHODSHere we established an aGVHD mouse model and explored the relation between aGVHD onset and variations of some cytokines. Based on the results and latest progress, we selected 16 cytokines and compared their serum variations in aGVHD patients and non-aGVHD patients after allogeneic hematopoietic stem cell transplantation. Using protein microarray, we explored the relation between the cytokine levels and aGVHD-related events (onset, grading, and steroid sensitivity).RESULTSThe increase of chemokine levels in murine aGVHD was very consistent with that of patients. We found obviously higher levels of IL-2, IL-4, Elafin, sST2, TLR4, and TNF-α, and lower levels of TGF-ß in both aGVHD mouse models and aGVHD patients. In addition, patients with severe aGVHD showed increased IL-6, TLR4, TNF receptor 1 (TNFR1), and Elafin and decreased TGF-ß. TLR4 and TNFR1 were significantly increased in steroid-refractory aGVHD patients compared with steroid-effective patients (P < 0.05).CONCLUSIONA combination of TLR4, TNFR1, TGF-ß, and Elafin could be a new 4-biomarker panel to assist aGVHD diagnosis, grading, and evaluation of steroid sensitivity for clinical aGVHD patients.TRIAL REGISTRATIONChiCTR1900022292 "Clinical Research of Umbilical Cord-Derived Mesenchymal Stromal Cells in the Prophylaxis of Graft-Versus-Host Disease After HLA-Haploidentical Stem-Cell Transplantation."FUNDINGNational Key Research Program, National Natural Science Foundation of China, Chongqing Social Career and People's Livelihood Security Science and Technology Innovation Project, Fundamental and Frontier Research Program of Chongqing, and Foundation of Xinqiao Hospital.

6.
Medicine (Baltimore) ; 98(32): e16693, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393371

RESUMO

To strengthen rural health services, the Chinese government has launched a series of policies to promote health workforce development. This study aims to understand the current status of village doctors and to explore the factors associated with village doctors' job satisfaction in western China. It also attempts to provide references for further building capacities of village doctors and promoting the development of rural health service policy.A multistage stratified sampling method was used to obtain data from a cross-sectional survey on village doctors across 2 provinces of western China during 2012 to 2013. Quantitative data were collected from village doctors face-to-face, through a self-administered questionnaire.Among the 370 respondents, 225 (60.8%) aged 25 to 44 years, and 268 (72.4%) were covered by health insurance. Their income and working time calculated by workloads were higher than their self-report results. Being healthy, working fewer years, and having government funding and facilities were the positive factors toward their job satisfaction. Village doctors working with government-funded village clinics or facilities were more likely to feel satisfied.Problems identified previously such as low income and lack of insurance, heavy workload and aging were not detected in our study. Instead, village doctors were better-paid and better-covered by social insurance than other local rural residents, with increased job satisfaction. Government policies should pay more attention to improving the quality of rural health services and the income and security system of village doctors, to maintain and increase their job satisfaction and work enthusiasm. Further experimental study could evaluate effects of government input to improve rural health human resources and system development.


Assuntos
Satisfação no Emprego , Médicos/psicologia , Serviços de Saúde Rural/organização & administração , Adulto , Atitude do Pessoal de Saúde , Fortalecimento Institucional , China , Estudos Transversais , Humanos , Serviços de Saúde Rural/legislação & jurisprudência , Autorrelato
7.
Artigo em Inglês | MEDLINE | ID: mdl-31386585

RESUMO

Background: Tetralogy of Fallot (TOF) accounts for ∼10% of congenital heart disease cases. The blood vessel epicardial substance (BVES) gene has been reported to play a role in the function of adult hearts. However, whether allelic variants in BVES contribute to the risk of TOF and its possible mechanism remains unknown. Methods: The open reading frame of the BVES gene was sequenced using samples from 146 TOF patients and 100 unrelated healthy controls. qRT-PCR and western blot assays were used to confirm the expression of mutated BVES variants in the TOF samples. The online software Polyphen2 and SIFT were used to predict the deleterious effects of the observed allelic variants. The effects of these allelic variants on the transcriptional activities of genes were examined using dual-fluorescence reporter assays. Results: We genotyped four single nucleotide polymorphisms (SNPs) in the BVES gene from each of the 146 TOF patients. Among them, the minor allelic frequencies of c.385C>T (p.R129W) were 0.035% in TOF, but ∼0.025% in 100 controls and the Chinese Millionome Database. This allelic variant was predicted to be a potentially harmful alteration by the Polyphen2 and SIFT softwares. qRT-PCR and western blot analyses indicated that the expression of BVES in the six right ventricular outflow tract samples with the c.385C>T allelic variant was significantly downregulated. A dual-fluorescence reporter system showed that the c.385C>T allelic variant significantly decreased the transcriptional activity of the BVES gene and also decreased transcription from the GATA4 and NKX2.5 promoters. Conclusions: c.385C>T (p.R129W) is a functional SNP of the BVES gene that reduces the transcriptional activity of BVES in vitro and in vivo in TOF tissues. This subsequently affects the transcriptional activities of GATA4 and NKX2.5 related to TOF. These findings suggest that c.385C>T may be associated with the risk of TOF in the Han Chinese population.

8.
Food Chem ; 298: 125081, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260952

RESUMO

The impact of kansui on the dough rheology and quality characteristics of chickpea-wheat composite flour-based noodles was investigated. For noodle dough, both the relative crystallinity and degree of order obtained from X-ray diffraction and Fourier transform infrared spectroscopy increased with the low level of kansui addition (0.5-1.5%), followed by a decreased trend at higher levels of alkali concentration (2.0-3.0%). Such variation was in accordance with the trend observed for G' and G″. Based on the confocal laser scanning microscopic observation for cooked noodle samples, the low concentration of kansui addition (0.5-1.5%) protected the well-embedded starch granules being disassociate from the gluten network, whereas with the increased alkali addition (2.0-3.0%), the protein network was impaired with a greater amount of ruptured starch granules being disassociated from the gluten network. The observation corresponded well with the electrophoretic profile, and the results of cooking properties, -SH content, and textural properties of cooked noodles.

9.
Chin Med J (Engl) ; 132(13): 1550-1562, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268882

RESUMO

BACKGROUND: Management of tumors has become more complex owing to tumor heterogeneity. Fewer studies have been performed on intra-tumor heterogeneity of endometrial cancer (EC) until now. Therefore, it is of great clinical value to explore the intra-tumor heterogeneity of EC based on clinical features and gene expression profiles. METHODS: A total of 1688 patients with EC were screened and 114 patients were finally selected, including specimens from 84 patients with primary EC without relapse (PE) and the paired metastases (P-M) specimens, as well as specimens from 30 patients with primary EC with relapse (RPE) and the paired relapsed EC (P-RE) specimens. Microarray and RNA-seq were used to detect gene expression of EC samples. Clinicopathological characteristics and molecular data were compared between PE and P-M groups and between RPE and P-RE groups to explore the intra-tumor heterogeneity of EC. RESULTS: The clinical intra-tumor spatial heterogeneity of pathological type, grade, ER status, and PR status between PE and P-M were 17.9%, 13.1%, 28.6%, and 28.6%, respectively. The clinical intra-tumor spatiotemporal heterogeneity of pathological type, grade, ER status, and PR status between RPE and P-RE were 16.7%, 33.3%, 25.0%, and 37.5%, respectively. Cluster analysis sorts EC samples based on progression type of lesion and their pathological type. There were differentially expressed genes between PE and P-M and between RPE and P-RE, of which gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis were mainly enriched in cell proliferation, the p53 signaling pathway, etc. CONCLUSIONS:: Clinical and molecular data showed that there was spatiotemporal heterogeneity in intra-tumor of EC, which may add to the complexity of diagnosis and therapeutics for EC. Considering the intra-tumor heterogeneity, sequential chemotherapy and precision medicine may be a more suitable treatment plan for EC.

10.
J Food Biochem ; 43(2): e12713, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31353643

RESUMO

A chitinase was purified from naked oat (Avena chinensis) seeds using simple chromatographic techniques. Its molecular weight and isoelectric point were determined as 35 kDa and 8.9, respectively. The purified chitinase exhibited specific activity of 3.6 U/mg and 15.6% yield using colloidal chitin as substrate. Partial amino acid sequence analysis and homology search indicated that it probably belonged to Class I plant chitinase, glycosyl hydrolase family 19. With chitin as substrate, the optimum pH and temperature of the chitinase were pH 7.0 and 40°C, respectively. The chitinase was remarkably stable from 30°C up to 50°C, but was inactivated at high temperatures above 85°C. Antifungal activity in vitro tests demonstrated this purified chitinase had potent, dose-dependent inhibitory activity against the fungi Panus conchatus and Trichoderma reesei. PRACTICAL APPLICATIONS: Chitinase has broad applications in many fields including the food industry and is recognized as one of the antifungal substances with potential use in plant disease resistance or biological control in agriculture. This study developed cost-effective purification methods for producing chitinase from naked oat (Avena chinensis) seeds, which may favor large-scale production of the enzyme. The remarkable stability of the chitinase at moderate temperatures (30°C-50°C), makes it a potentially useful enzyme in bioprocessing to produce chitooligosaccharides for various applications in the food, health, and agriculture sectors.

11.
Genomics ; 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31295545

RESUMO

Competing endogenous RNAs (ceRNAs) are considered as transcripts that can regulate each other at post-transcription level by competing for shared miRNAs. Considering the key roles of lncRNAs acting as ceRNAs in progression of solid tumors, to develop prognostic signatures in thyroid cancer (THCA), patients with corresponding clinical data were selected and two ceRNA networks were constructed using online databases. Two prognostic signatures (Lnc5m4 and Lnc2mi1m2) were found to be more efficient in predicting long-term survival of THCA patients. However, the high-risk score of Lnc2mi1m2 was not an independent factor.The risk score of Lnc5m4 was able to effectively stratify patients in stage III-IV into low- and high-risk groups, and also could predict poor prognosis of patients in stage III-IV. In conclusion, these findings indicate that Lnc5m4 is a novel prognostic signature for predicting long-term overall survival of THCA patients, which could provide a new approach to lncRNA research in THCA progression.

12.
Environ Microbiol ; 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291045

RESUMO

FgPrp4, the only kinase in the spliceosome, is not essential for viability, but is important for splicing efficiency in Fusarium graminearum. The Fgprp4 deletion mutant had severe growth defects but often produced spontaneous suppressors with faster growth rate. To better understand the suppression mechanism, we identified and characterized spontaneous mutations in the tri-snRNP-specific protein, FgSad1, which suppressed the growth defects of Fgprp4. The L512P mutation was verified for its suppressive effects on Fgprp4, suggesting that mutations in FgSad1 may have effects involving FgPrp4 phosphorylation on FgSad1. Phosphoproteomics analysis showed that FgSad1 may not be the direct substrate of FgPrp4 kinase. Furthermore, truncation analysis showed that the N-terminal, extra RS-rich region of FgSad1 is critical for its function and is post-translationally modified. The P258S or S269P mutations in FgSad1 increased its interactions with the U5 protein FgPrp8 and the U4/U6 protein FgPrp31, which may result in tri-snRNP stabilization. Additionally, the D76N mutation increased the association of FgSad1 with the U2 snRNP. These data indicate that suppressor mutations in FgSad1 increase the stability of the tri-snRNP and/or the affinity of FgSad1 with U2 snRNP and therefore potentially facilitate the docking of tri-snRNP into the spliceosome.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31286175

RESUMO

Sixty-two topsoil samples were collected within the third ring road of Xi'an City in Northwest China and analyzed by X-ray fluorescence spectrometry for the concentrations of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn. The pollution levels of trace metals were assessed by pollution index (PI) and Nemerow pollution index (NPI). Meanwhile, the sources of trace metals were apportioned by receptor models, including positive matrix factorization (PMF), UNMIX, and principal component analysis-multiple linear regression (PCA-MLR). The average concentrations of the trace metals analyzed in the urban soil exceeded the corresponding soil element background values of Shaanxi Province, especially for Co, which was 2.38 times higher than the corresponding background value. The mean of PI was 2.38 for Co, reflecting a moderate pollution level, and ranged from 1.07 to 1.72 for other trace metals, presenting slight pollution levels. The NPI of trace metals varied between 1.20 and 3.50 with an average of 2.00, indicating that trace metals presented slight pollution in 62.90% of soil samples, moderate pollution in 30.65% of soil samples, and heavy pollution in 6.45% of soil samples, respectively. Three sources of trace metals apportioned by the three receptor models were mixed nature and anthropogenic source, traffic exhaust, and industrial emissions. The contributions of them were 38.58%, 32.72%, and 28.70% from the PMF, 65.36%, 17.76%, and 16.88% through the UNMIX and 49.16%, 38.90%, and 11.94% via the PCA-MLR, respectively. Meanwhile, the study results suggested that the combined usage of multiple receptor models is a good method to apportion the source compositions and contributions of trace metals in urban soil.

14.
FEBS Lett ; 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31273779

RESUMO

Endogenous estrogen deficiency accelerates many diseases in postmenopausal women, and gut microbes contribute to estrogen level modulation. However, the compositional alterations and influences of the gut microbiota in postmenopausal women remain uncertain. A metagenome-wide association study was performed to compare the gut microbiota of 24 premenopausal and 24 postmenopausal women. Firmicutes and Roseburia spp. are depleted, while Bacteroidetes and the toluene-producing genus Tolumonas are overrepresented in fecal samples from postmenopausal women. The pentose phosphate pathway is enriched in premenopausal women. Homocysteine synthesis-related processes are enriched in postmenopausal women. The gut microbiomes of premenopausal and postmenopausal women differ and produce different metabolites. The gut microbiome may be a therapeutic target to reduce risks and improve the quality of life in postmenopausal women.

15.
J Sci Food Agric ; 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31294827

RESUMO

BACKGROUND: The presence of acrylamide in food has attracted wide attention and has raised concerns due to its potential toxic and carcinogenic effects. The phenolic compounds in buckwheat display strong antioxidant activity, which may affect the acrylamide levels. The aims of this study were to evaluate the effect of buckwheat extracts on acrylamide formation and the quality of the bread, and to investigate possible inhibitory mechanisms. RESULTS: The extracts from Tartary buckwheat seeds, Tartary buckwheat sprouts, common buckwheat seeds, and common buckwheat sprouts reduced acrylamide level in bread by 23.5, 27.3, 17.0, and 16.7%, respectively. In addition, all four buckwheat extracts significantly (P < 0.05) reduced acrylamide levels in the asparagine / glucose system. There were significant positive correlations between total phenolic compound content, the antioxidant activity of the extracts, and the reduction in the acrylamide level. Evaluation of the organoleptic and textural properties indicated that the addition of the extracts did not significantly affect the crust color, aroma, taste, crumb appearance, and hardness of the bread. CONCLUSION: This study showed that proper use of buckwheat extracts can reduce acrylamide levels in bread without having a significant impact on their properties. The study also revealed that a possible acrylamide formation inhibitory mechanism involved the Maillard reaction through the asparagine / glucose pathway. The study also provided useful information for the further application of buckwheat in improving food safety. © 2019 Society of Chemical Industry.

16.
J Chem Phys ; 150(20): 204307, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31153183

RESUMO

We present numerical results for the dipole induced by interactions between a hydrogen molecule and a hydrogen atom, obtained from finite-field calculations in an aug-cc-pV5Z basis at the unrestricted coupled-cluster level including all single and double excitations in the exponential operator applied to a restricted Hartree-Fock reference state, with the triple excitations treated perturbatively, i.e., UCCSD(T) level. The Cartesian components of the dipole have been computed for nine different bond lengths r of H2 ranging from 0.942 a.u. to 2.801 a.u., for 16 different separations R between the centers of mass of H2 and H between 3.0 a.u. and 10.0 a.u., and for 19 angles θ between the H2 bond vector r and the vector R from the H2 center of mass to the nucleus of the H atom, ranging from 0° to 90° in intervals of 5°. We have expanded the interaction-induced dipole as a series in the spherical harmonics of the orientation angles of the H2 bond axis and of the intermolecular vector, with coefficients DλL(r, R). For the geometrical configurations that we have studied in this work, the most important coefficients DλL(r, R) in the series expansion are D01(r, R), D21(r, R), D23(r, R), D43(r, R), and D45(r, R). We show that the ab initio results for D23(r, R) and D45(r, R) converge to the classical induction forms at large R. The convergence of D45(r, R) to the hexadecapolar induction form is demonstrated for the first time. Close agreement between the long-range ab initio values of D01(r0 = 1.449 a.u., R) and the known analytical values due to van der Waals dispersion and back induction is also demonstrated for the first time. At shorter range, D01(r, R) characterizes isotropic overlap and exchange effects, as well as dispersion. The coefficients D21(r, R) and D43(r, R) represent anisotropic overlap effects. Our results for the DλL(r, R) coefficients are useful for calculations of the line shapes for collision-induced absorption and collision-induced emission in the infrared and far-infrared by gas mixtures containing both H2 molecules and H atoms.

17.
J Org Chem ; 84(12): 8035-8045, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31188599

RESUMO

An asymmetric cyclization reaction of azadienes and azlactones was investigated by employing a Cinchona squaramide catalyst, which could afford a series of benzofuran-fused six-membered heterocycles containing a α,α-disubstituted amino acid unit in a highly diastereoselective (>20:1 dr) and enantioselective (up to 99% ee) manner with good to excellent yields (up to 92%). A plausible pathway was proposed to explain the reaction process.

19.
Carbohydr Polym ; 218: 163-169, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31221317

RESUMO

In this study, the effects of natural fermentation on the multi-scale structure and physicochemical properties of wheat starch were investigated. The results showed that fermentation reduced weight-average molecular weight (Mw) and slightly eroded the starch granule surface. An obvious increase in relative crystallinity from X-ray diffraction was observed in all fermented starch (39.38-42.27%) when compared with native starch (37.15%). Data from small angle X-ray scattering revealed that fermentation increased the crystalline layer and decreased the amorphous region of the starch granules. The intensity of absorption related to hydrogen bonding by FT-IR (3000-3600 cm-1) also increased in fermented starch. The rapid viscosity analysis results showed that fermented starch had a lower peak viscosity and final viscosity, and a lower setback value than native starch. The present results reveal that fermentation is an effective method to modify wheat starch and suggest its potential to improve the quality of starch-based foods.

20.
Nat Commun ; 10(1): 2852, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253764

RESUMO

Cytosine base editors (CBEs) enable programmable C-to-T conversion without DNA double-stranded breaks and homology-directed repair in a variety of organisms, which exhibit great potential for agricultural and biomedical applications. However, all reported cases only involved C-to-T substitution at a single targeted genomic site. Whether C-to-T substitution is effective in multiple sites/loci has not been verified in large animals. Here, by using pigs, an important animal for agriculture and biomedicine, as the subjective animal, we showed that CBEs could efficiently induce C-to-T conversions at multiple sites/loci with the combination of three genes, including DMD, TYR, and LMNA, or RAG1, RAG2, and IL2RG, simultaneously, at the embryonic and cellular levels. CBEs also could disrupt genes (pol gene of porcine endogenous retrovirus) with dozens of copies by introducing multiple premature stop codons. With the CBEs, pigs carrying single gene or multiple gene point mutations were generated through embryo injection or nuclear transfer approach.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Mutação Puntual , Suínos/genética , Desaminase APOBEC-1 , Animais , Sequência de Bases , Proteína 9 Associada à CRISPR , DNA/genética , Técnicas de Cultura Embrionária , Embrião de Mamíferos , Genoma , Técnicas de Transferência Nuclear/veterinária , RNA Guia/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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