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1.
Food Chem ; 304: 125444, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491712

RESUMO

Poor aqueous solubility of some minor steviol glycosides (SGs) has prevented their potential widespread usage as non-nutritional high intensity sweeteners in beverage industry. Rebaudioside B (reb B) is one of the minor SGs found in stevia leaf, and has a better taste quality than many of the major SGs. However, reb B suffers from poor aqueous solubility and low dissolution rate, which greatly limits its application, especially in beverages. In our effort to enhance its solubility by using natural means, we discovered that under certain conditions reb B forms hemihydrate crystal, which has much lower solubility and dissolution rate than commercial powder reb B product. The crystal was characterized by Fourier Transform Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD). This may offer more insight into the interaction of SGs with water at molecular level, and therefore provide new guidance on current efforts to enhance the solubility of SGs.

2.
J Clin Lab Anal ; : e23090, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692065

RESUMO

OBJECTIVE: The purpose of our research was to demonstrate the clinical significance of serum bilirubin in primary Sjögren syndrome patients (pSS). PATIENTS AND METHODS: A total of 116 patients with primary Sjögren syndrome and 138 matched individuals were included in our study. The laboratory parameters of patients with pSS and healthy controls were retrospectively analyzed. RESULTS: Serum total bilirubin, direct bilirubin, and indirect bilirubin were significantly reduced (P < .001, P = .001, P < .001) while ESR was significantly increased (P < .001) in patients with pSS when compared with healthy checkup individuals. Statistically, the AUC in patients with pSS is as follows: TBIL = 0.77, P < .001, cutoff value = 7.96; DBIL = 0.617, P = .001 cutoff value = 2.2; and IBIL = 0.786, P < .001 cutoff value = 4.5. Furthermore, our study revealed that TBIL, DBIL, and IBIL were significantly negativity related to ESR (r = -.406, P < .001; r = -.206, P = .026; r = -.429, P < .001). Interestingly, multiple linear regression analysis showed that when adjusted for sex, age, ALT, and AST, the levels of TBIL, DBIL, and IBIL in patients with pSS were independently correlated with ESR. CONCLUSIONS: This study found that the levels of serum bilirubin were reduced and the inflammatory marker was elevated in patients with pSS. Additionally, serum bilirubin was negatively related with ESR and TBIL, DBIL, and IBIL can be used in the clinical diagnosis and follow-up visits of the patients with pSS.

3.
Ecotoxicol Environ Saf ; 187: 109846, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31677563

RESUMO

At present, the public is paying more attention to the adverse effects of pesticides on human and animal health and the environment. Glyphosate is a broad-spectrum pesticide that is widely used in agricultural production. In this manuscript, the effects of diets containing glyphosate on intestinal morphology, intestinal immune factors, intestinal antioxidant capacity and the mRNA expression associated with the Nrf2 signaling pathway were investigated in weaned piglets. Twenty-eight healthy female hybrid weaned piglets (Duroc × Landrace × Yorkshire) were randomly selected with an average weight of 12.24 ±â€¯0.61 kg. Weaned piglets were randomly assigned into 4 treatment groups and fed a basal diet supplemented with 0, 10, 20, and 40 mg/kg glyphosate for a 35-day feeding trial. We found that glyphosate had no effect on intestinal morphology. In the duodenum, glyphosate increased the activities of CAT and SOD (linear, P < 0.05) and increased the levels of MDA (linear and quadratic, P < 0.05). In the duodenum, glyphosate remarkably increased the relative mRNA expression levels of Nrf2 (linear and quadratic, P < 0.05) and NQO1 (linear and quadratic, P < 0.05) and reduced the relative mRNA expression levels of GPx1, HO-1 and GCLM (linear and quadratic, P < 0.05). In the jejunum, glyphosate remarkably increased the relative mRNA expression levels of Nrf2 (linear and quadratic, P < 0.05) and decreased the relative mRNA expression levels of GCLM (linear and quadratic, P < 0.05). Glyphosate increased the mRNA expression levels of IL-6 in the duodenum (linear and quadratic, P < 0.05) and the mRNA expression levels of IL-6 in the jejunum (linear, P < 0.05). Glyphosate increased the mRNA expression of NF-κB in the jejunum (linear, P = 0.05). Additionally, the results demonstrated that glyphosate linearly decreased the ZO-1 mRNA expression levels in the jejunum and the mRNA expression of claudin-1 in the duodenum (P < 0.05). In the duodenum, glyphosate increased the protein expression levels of Nrf2 (linear, P = 0.025). Overall, glyphosate exposure may result in oxidative stress in the intestines of piglets, which can be alleviated by enhancing the activities of antioxidant enzymes and self-detoxification.

4.
Medicine (Baltimore) ; 98(45): e17933, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702679

RESUMO

Hemiplegic shoulder pain (HSP), which occurs in most patients with hemiplegia, causes considerable distress and worsens outcomes in rehabilitation. Although they have received the treatments such as anti-inflammatory drugs or physical therapy, many of the individuals remain suffering from shoulder pain 6 months after acute stroke event. In this retrospective study, we evaluated the effectiveness of ultrasound guided subacromial-subdeltoid (SASD) bursa injections with botulinum toxin type A (BoNT/A) compared to steroids for refractory HSP.The data were collected retrospectively by reviewing the patient's medical records and pain questionnaires in our rehabilitation center. In total, 38 patients who received ultrasound guided SASD bursa injection (BoNT/A group, n = 18; corticosteroid group, n = 20) were included. The pain visual analog scale (VAS) score at rest and during arm passive abduction, Fugl-Meyer score of upper limbs (F-M score) were evaluated before, 2, 4, 8, and 12 weeks after injection.Both 2 groups obtained a significant improvement of VAS score at rest or during arms passive abduction compared to baseline score (within group compare, P < .05). There were no significant differences of pain score improvement between two groups at week 2, 4, 8, and 12 after injection either at rest or during passive arm abduction (between 2 groups compare, P > .05). There were also no differences in results of the post treatment F-M score between 2 groups (between 2 groups compare, P > .05). Similarly, during the follow-up period no collateral effects were reported after BoNT/A injection.SASD bursa BoNT/A injection can substantially reduce the pain as corticosteroid in patients with HSP. BoNT/A injection could be a useful strategy for replacing steroids as a treatment for refractory HSP especially in the patients who cannot tolerate the steroids injection.

5.
Life Sci ; : 116985, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31647949

RESUMO

BACKGROUND: The infiltration and activation of macrophages play key roles in arterial restenosis, providing a promising strategy for the treatment of restenosis caused by intimal hyperplasia. Although miR-150 has been implicated in cardiovascular diseases, the individual effect of miR-150 on intimal hyperplasia remains unclear. METHODS AND RESULTS: We observed that the expression of miR-150 was robustly reduced in proinflammatory M1 macrophages and reversely induced in resolving M2 macrophages. An in vitro experiment demonstrated that miR-150 deficiency promoted extensive upregulation of the expression of M1 markers but attenuated the expression of M2 macrophage markers. MiR-150 enhanced the proliferation and migration of vascular smooth muscle cells (VSMCs) when co-cultured with conditioned medium from polarized macrophages upon LPS or IL-4 stimulation. Mechanistically, the bioinformatics analysis and luciferase assay results showed that miR-150 directly targeted STAT1 and STAT1 was required for the effect of miR-150 knockout on macrophage polarization. More importantly, we showed that knockout of miR-150 accelerated neointima formation, accompanied by the activation of M1 macrophages and the inactivation of M2 macrophages. Furthermore, miR-150 deficiency in marrow-derived cell accelerated neointima formation. CONCLUSION: Our research demonstrated that miR-150 deficiency promoted intimal hyperplasia with high ratios of M1 to M2 macrophages and subsequently increased VSMCs proliferation and migration, which were partially mediated by directly targeting to STAT1. Collectively, these results suggested that miR-150 may act as a novel therapeutic target for arterial restenosis.

6.
Clin Cancer Res ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573956

RESUMO

PURPOSE: The success of checkpoint blockade has led to a significant increase in the development of a broad range of immunomodulatory molecules for the treatment of cancer, including agonists against T-cell costimulatory receptors, such as OX40. Unlike checkpoint blockade, where complete and sustained receptor saturation may be required for maximal activity, the optimal dosing regimen and receptor occupancy for agonist agents is less well understood and requires further study. EXPERIMENTAL DESIGN: We integrated both preclinical and clinical biomarker data sets centered on dose, exposure, receptor occupancy, receptor engagement, and downstream pharmacodynamic changes to model the optimal dose and schedule for the OX40 agonist antibody BMS-986178 alone and in combination with checkpoint blockade. RESULTS: Administration of the ligand-blocking anti-mouse surrogate antibody OX40.23 or BMS-986178 as monotherapy or in combination with checkpoint blockade led to increased peripheral CD4+ and CD8+ T-cell activation in tumor-bearing mice and patients with solid tumors, respectively. OX40 receptor occupancy between 20% and 50% both in vitro and in vivo was associated with maximal enhancement of T-cell effector function by anti-OX40 treatment, whereas a receptor occupancy > 40% led to a profound loss in OX40 receptor expression, with clear implications for availability for repeat dosing. CONCLUSIONS: Our results highlight the value of an integrated translational approach applied during early clinical development to aggregate preclinical and clinical data in an effort to define the optimal dose and schedule for T-cell agonists in the clinic.

7.
Psychiatry Res ; 282: 112608, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31655405

RESUMO

OBJECTIVES: Abnormalities in insular functional connectivity have been implicated in many clinical features of schizophrenia. The aim of this study was to determine to what degree such abnormalities occur in individuals with clinical high risk for psychosis (CHR), and whether which is associated with symptom severity. METHODS: Resting-state fMRI data were collected from 47 healthy controls, 24 CHR individuals and 19 patients with first-episode schizophrenia. Using the posterior, dorsal and ventral insular subregions as separate seeds, we examined resting-state functional connectivity differences between different groups and the association between concurrent symptom severity and dysconnectivity. RESULTS: Compared with healthy controls, both CHR individuals and schizophrenia patients showed hypoconnectivity between posterior insula (PI) and somatosensory areas, and between dorsal anterior insula (dAI) and putamen. Schizophrenia patients also showed dAI and ventral anterior insula(vAI) hyperconnectivity with visual areas relative to controls and CHR individuals. Correlation analysis revealed that dAI functional connectivity with superior temporal gyrus was positively correlated with positive symptoms of CHR, and vAI connectivity with dorsolateral prefrontal cortex was negatively correlated with the severity of the symptoms of first-episode schizophrenia. CONCLUSIONS: Our findings suggest that insular functional dysconnectivity with the sensory cortex may be a system-level neural substrate preceding the onset of psychosis.

8.
Adv Mater ; : e1904341, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621958

RESUMO

Current approaches to fabrication of nSC composites for bone tissue engineering (BTE) have limited capacity to achieve uniform surface functionalization while replicating the complex architecture and bioactivity of native bone, compromising application of these nanocomposites for in situ bone regeneration. A robust biosilicification strategy is reported to impart a uniform and stable osteoinductive surface to porous collagen scaffolds. The resultant nSC composites possess a native-bone-like porous structure and a nanosilica coating. The osteoinductivity of the nSC scaffolds is strongly dependent on the surface roughness and silicon content in the silica coating. Notably, without the use of exogenous cells and growth factors (GFs), the nSC scaffolds induce successful repair of a critical-sized calvarium defect in a rabbit model. It is revealed that topographic and chemical cues presented by nSC scaffolds could synergistically activate multiple signaling pathways related to mesenchymal stem cell recruitment and bone regeneration. Thus, this facile surface biosilicification approach could be valuable by enabling production of BTE scaffolds with large sizes, complex porous structures, and varied osteoinductivity. The nanosilica-functionalized scaffolds can be implanted via a cell/GF-free, one-step surgery for in situ bone regeneration, thus demonstrating high potential for clinical translation in treatment of massive bone defects.

9.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 423-426, 2019 Sep 19.
Artigo em Chinês | MEDLINE | ID: mdl-31612680

RESUMO

OBJECTIVE: To evaluate the effects of intravenous injection of different blood components containing Babesia microti on B. microti infection in mice. METHODS: Healthy mice were infected with B. microti, and then blood samples were collected from the mouse orbit to prepare whole blood, serum-free blood components and pure red blood cells containing B. microti. Twenty seven BALB/c mice were divided into three groups, including the whole blood group, the serum-free blood component group and the pure red blood cell group, of 9 mice in each group, and then, each group was divided into three subgroups, of 3 mice in each subgroup, which were injected with 100 µL of blood components containing B. microti at concentrations of 9.00, 0.90, 0.09 B. microti parasites/µL (900, 90, 9 B. microti parasites) via the tail vein, respectively. Blood samples were collected from the mouse tail tip every other day since one day post-injection to prepare thin blood smears. Following Giemsa staining of blood smears, B. microti infection was identified in red blood cells using microscopy. RESULTS: Following injection of 900 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group and the serum-free blood component group 3 days post-injection, and the density of B. microti parasites started to increase 15 days post-injection and peaked 21 days post-injection, with 2.21% and 1.76% rates of B. microti infection in red blood cells, respectively. Subsequently, the density of B. microti parasites declined, and the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was found in the peripheral blood in the pure red blood cell group. Following injection of 90 B. microti parasites, B. microti was identified in the peripheral blood in the whole blood group 3 days post-injection, and the density of B. microti parasites increased 15 days post-injection and peaked 21 days post-injection, with a 1.35% rate of B. microti infection in red blood cells, while the percentage of B. microti infection in red blood cells tended to be 0 31 days post-injection. During the study period, no B. microti was detected in the peripheral blood in the serum-free blood component group or the pure red blood cell group. Following injection of 9 B. microti parasites, no B. microti was detected in the peripheral blood in the whole blood group, the serum-free blood component group or the pure red blood cell group. CONCLUSIONS: Blood components and dose of B. microti parasites may affect intravenous injection of B. microti injection in mice, and transfusion of blood components may case a risk of Babesia infection.


Assuntos
Babesia microti , Babesiose , Transfusão de Componentes Sanguíneos , Animais , Babesiose/sangue , Babesiose/transmissão , Transfusão de Componentes Sanguíneos/efeitos adversos , Eritrócitos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Fatores de Tempo
10.
Nature ; 574(7779): 565-570, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645726

RESUMO

Co-inhibitory immune receptors can contribute to T cell dysfunction in patients with cancer1,2. Blocking antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) partially reverse this effect and are becoming standard of care in an increasing number of malignancies3. However, many of the other axes by which tumours become inhospitable to T cells are not fully understood. Here we report that V-domain immunoglobulin suppressor of T cell activation (VISTA) engages and suppresses T cells selectively at acidic pH such as that found in tumour microenvironments. Multiple histidine residues along the rim of the VISTA extracellular domain mediate binding to the adhesion and co-inhibitory receptor P-selectin glycoprotein ligand-1 (PSGL-1). Antibodies engineered to selectively bind and block this interaction in acidic environments were sufficient to reverse VISTA-mediated immune suppression in vivo. These findings identify a mechanism by which VISTA may engender resistance to anti-tumour immune responses, as well as an unexpectedly determinative role for pH in immune co-receptor engagement.

11.
AJR Am J Roentgenol ; : 1-8, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31557054

RESUMO

OBJECTIVE. The purpose of this study was to investigate the utility of radiomics for predicting the malignancy of pulmonary nodules (PNs) of different sizes using unenhanced, thin-section CT images. MATERIALS AND METHODS. Patients with a single PN (n = 373) who underwent a preoperative chest CT were recruited retrospectively at Beijing Friendship Hospital from March 2015 to March 2018. Of the 373 PNs studied, 192 were benign and 181 were malignant. The lesions were classified into three groups (T1a, T1b, or T1c according to the 8th edition of the TNM staging system for lung cancer) on the basis of lesion diameters: T1a (diameter, 0-1 cm), T1b (1 cm < diameter ≤ 2 cm) and T1c (2 cm < diameter ≤ 3 cm). A total of 1160 radiomic features were extracted from PN segmentation on unenhanced CT images. We developed three radiomic models to predict PN malignancy in each group on the basis of the extracted radiomic features. Fivefold cross-validation was used to estimate AUC, accuracy, sensitivity, and specificity for indicating the performance of prediction models. RESULTS. The AUC, accuracy, sensitivity, and specificity for predicting PN malignancy in each group were 0.84, 0.77, 0.89, and 0.74 with the T1a model; 0.78, 0.73, 0.74, and 0.71 with the T1b model, and 0.79, 0.76, 0.77, and 0.73 with the T1c model, respectively. The most contributive radiomic features for predicting PN malignancy for groups T1a, T1b, and T1c were LoG_X_Uniformity, Intensity_Minimum, and Shape_SI9, respectively. CONCLUSION. Radiomic features based on unenhanced CT images can be used to predict the malignancy of pulmonary nodules. The radiomic T1a model showed superior prediction performance to the T1b and T1c models, and the best performance in terms of AUC and sensitivity was found for predicting the malignancy of T1a PN.

12.
Plant Sci ; 287: 110193, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481195

RESUMO

Oat (Avena sativa) and castor (Ricinus communis) accumulate a large amount of lipids in their endosperms, however the molecular mechanism remains unknown. In this study, differences in oil regulators between oat and wheat (Triticum aestivum) as well as common features between oat and castor were tested by analyzing their transcriptomes with further q-PCR analysis. Results indicated that WRINKLED1 (WRI1) homologs and their target genes highly expressed in the endosperms of oat and castor, but not in the starchy endosperms of wheat. Expression pattern of WRI1s was in agreement with that of oil accumulation. Three AsWRI1s (AsWRI1a, AsWRI1b and AsWRI1c) and one RcWRI1 were identified in the endosperms of oat and castor, respectively. AsWRI1c lacks VYL motif, which is different from the other three WRI1s. Expressions of these four WRI1s all complemented the phenotypes of Arabidopsis wri1-1 mutant. Overexpression of these WRI1s in Arabidopsis and tobacco BY2 cells increased oil contents of seeds and total fatty acids of the cells, respectively. Moreover, this overexpression also resulted in up-regulations of WRI1 target genes, such as PKp-ß1. Taken together, our results suggest that high and functional expression of WRI1 play a key role in the oil-rich endosperms and the VYL motif is dispensable for WRI1 function.

13.
Clin Infect Dis ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31504306

RESUMO

BACKGROUND: Population movement could extend multidrug-resistant tuberculosis (MDR-TB) transmission and complicate its global prevalence. We sought to identify the high-risk populations and geographic sites of MDR-TB transmission in Shenzhen, the most common destination for internal migrants in China. METHODS: We performed a population-based, retrospective study of patients who were diagnosed with MDR-TB in Shenzhen during 2013-2017. By defining genomic clusters with a threshold of 12 SNP distance based on whole-genome sequencing their clinical strains, the clustering rate was calculated to evaluate the level of recent transmission. Risk factors for MDR-TB transmission were identified by multivariable logistic regression. To further delineate the epidemiological links, we invited the genomic-clustered patients to an in-depth social network investigation. RESULTS: In total, 105 (25.2%) of the 417 enrolled MDR-TB patients were grouped into 40 genome clusters, suggesting recent transmission of MDR strains. The adjusted risk for students to have a clustered strain was 4.05 (95% confidential intervals [CI], 1.06-17.0) times greater than other patients. The majority (70%, 28/40) of the genomic clusters involved patients who lived in different districts, with residences separated by an average of 8.76 kilometers. Other than household members, confirmed epidemiological links were also identified among classmates and workplace colleagues. CONCLUSIONS: These findings demonstrate that local transmission of MDR-TB is a serious problem in Shenzhen city. While most transmission occurred between people who lived distant from each other, there was clear evidence that transmission occurred in schools and workplaces, which should be included as targeted sites for active case finding.

15.
Adv Exp Med Biol ; 1193: 107-120, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31368100

RESUMO

Myocardial ischemia-reperfusion (IR) injury during acute myocardial infarction or open-heart surgery would promote oxidative stress, leading to the accumulation of reactive aldehydes that cause cardiac damage. It has been well demonstrated that aldehyde dehydrogenase (ALDH)-2 is an important cardioprotective enzyme for its central role in the detoxification of reactive aldehydes. ALDH2 activation by small molecule activators is a promising approach for cardioprotection for myocardial IR injury.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Traumatismo por Reperfusão Miocárdica/genética , Miocárdio/enzimologia , Humanos , Mitocôndrias Cardíacas , Estresse Oxidativo
16.
Transl Oncol ; 12(11): 1516-1524, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450127

RESUMO

Epidermal growth factor receptor (EGFR) mutations were found in 30%-40% of non-small cell lung cancer (NSCLC) patients, who often responded well to EGFR tyrosine kinase inhibitors (EGFR-TKIs) as exemplified by erlotinib and gefitinib in the past decades. However, EGFR mutation-led drug resistance usually occurred upon prolonged treatment with EGFR-TKI. Herein, we study the anticancer effects of EGFR-TKI in combination with a newly developed antibody, A9(B8), to target a disintegrin and metalloprotease (ADAM) 17 that was overexpressed in NSCLC patients. NSCLC cell lines with different EGFR mutations were used to evaluate the drug combination. We have found that the EGFR-TKI-A9(B8) combination exhibited enhanced anticancer effects in NCI-H1975 cells harboring L858R and T790M mutations, which were due to simultaneous suppression of extracellular signal-regulated kinases phosphorylation. Our results suggested that targeting ADAM17 could potentiate the anticancer effects of EGFR-TKI against NSCLC and overcome drug resistance due to EGFR mutations.

17.
Biomaterials ; 220: 119409, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31404789

RESUMO

The zonal property of articular cartilage endows the tissue with biphasic mechanical properties to withstand shearing force and compressional loading. Current treatments for articular cartilage damage are not able to efficiently restore the zonal organisation and functionality. Size-based sorting of freshly isolated chondrocytes from full thickness (FT) cartilage using a spiral microfluidic device was shown to efficiently separate and enrich zonal chondrocytes. The translational application of this sorting protocol is challenging in the clinical setting due to the limited number of autologous chondrocytes from a patient. It is thus essential to explore the practicability of this sorting protocol on expanded chondrocytes. In this study, we first show that size-sorted zonal chondrocytes expanded on microcarriers in dynamic condition (dMC) were able to support comparable proliferation, while maintaining cell morphology, and the zonal cell size-phenotype relation, in contrast to expansion on a tissue culture plate. We further show that post-expansion size-based sorting can be applied on dMC-expanded FT chondrocytes, generating enriched zonal subpopulations that form phenotypically distinct cartilage constructs in the 3D hydrogel. This study demonstrates a novel scale-up zonal chondrocyte production protocol, incorporating size-based zonal chondrocyte separation and dMC platform, to maintain zonal chondrocytes' phenotypes better to support zonal repair of articular cartilage.

18.
ACS Synth Biol ; 8(9): 2121-2130, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31433622

RESUMO

A common challenge in the assembly and optimization of plant natural product biosynthetic pathways in recombinant hosts is the identification of gene orthologues that will result in best production titers. Here, we describe the modular assembly of a naringenin biosynthetic pathway in Saccharomyces cerevisiae that was facilitated by optimized naringenin-inducible prokaryotic transcription activators used as biosensors. The biosensors were designed and developed in S. cerevisiae by a multiparametric engineering strategy, which further was applied for the in vivo, high-throughput screening of the established yeast library. The workflow for assembling naringenin biosynthetic pathways involved Golden gate-directed combinatorial assembly of genes and promoters, resulting in a strain library ideally covering 972 combinations in S. cerevisiae. For improving the performance of our screening biosensor, a series of fundamental components was optimized, affecting the efficiency of the biosensor such as nuclear localization signal (NLS), the detector module and the effector module. One biosensor (pTDH3_NLS_FdeR-N_tPGK1-pGPM1-fdeO_mcherry_tTDH1-MV2) showed better performance, defined as better dynamic range and sensitivity than others established in this study as well as other previously reported naringenin biosensors. Using this biosensor, we were able to identify a recombinant S. cerevisiae strain as the most efficient candidate for the production of naringenin from the established naringenin biosynthetic library. This approach can be exploited for the optimization of other metabolites derived from the flavonoid biosynthetic pathways and more importantly employed in the characterization of putative flavonoid biosynthetic genes.

19.
J Anim Sci ; 97(10): 4235-4241, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31430375

RESUMO

The objective of this study was to investigate the effects of diets supplemented with sodium stearoyl-2-lactylate (SSL), polyglycerol fatty acid ester (PGFE), and combined emulsifiers (0.02% SSL and 0.08% PGFE) on growth performance, nutrient digestibility, and plasma lipid profiles in weaned piglets and to further evaluate the possible effects of feeding exogenous emulsifiers on digestive enzyme activities and liver bile acid (BA) metabolism. Twenty-eight barrows (age at 35 d, Duroc × Landrace × Yorkshire) with an initial BW of 10.13 ± 0.16 kg were randomly assigned to 4 dietary treatment groups (7 pigs/treatment). Dietary treatment groups included the following: 1) basal diet (Control, CTR); 2) basal diet with 0.1% SSL (SSL); 3) basal diet with 0.1% PGFE (PGFE); and 4) basal diet with 0.08% PGFE+0.02% SSL (PG-SL). SSL diet increased ADG and ADFI of piglets during day 0 to 17 (P < 0.05) compared with the CTR treatment. Piglets fed emulsifier diets experienced a significant improvement in the digestibility of nutrients (DM, CP, ether extract, energy, calcium, and phosphorus) during the first 17 d (P < 0.05). The level of low-density lipoprotein cholesterol (LDL-C) was lower in the PGFE and PG-SL treatment groups than in the CTR treatment group (P < 0.05). Feeding emulsifier diets increased the lipase activity of the pancreas when compared with the CTR diet (P < 0.05). Moreover, the emulsifier diets significantly increased the mRNA expression of FXR (P < 0.05) and decreased the mRNA expression of CYP27A1 (P < 0.05) in the liver. In conclusion, the addition of emulsifiers improved nutrient digestibility and increased the mRNA expression of FXR BA receptors while inhibiting the mRNA expression of BA biosynthesis by CYP27A1 in weanling piglets.

20.
Antiviral Res ; 170: 104564, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31336147

RESUMO

Influenza virus A H7N9 remains a serious threat to public health due to the lack of effective vaccines and drugs. In this study, a neutralizing human antibody named 3L11 was rapidly isolated from the switched memory B cells of a patient infected with H7N9. The antibody 3L11 was encoded by the heavy-chain VH1-8 gene and the light-chain VL2-13 gene that had undergone somatic mutations, and conferred high affinity binding to H7N9 hemagglutinins (HAs). It promoted killing of infected cells by antibody-dependent cell-mediated cytotoxicity (ADCC). Epitope mapping by mass spectroscopy (MS) indicated that 3L11 bound to the peptide 149-175 of HAs that contained the 150-loop of the receptor-binding site (RBS). Additionally, the 3L11 escape strains had G151R (Gly151→Arg151) and S152P (Ser152→Pro152) mutations within a conserved antigenic site A near the RBS that were not observed in field strains. Importantly, 3L11 fully protected mice against a lethal H7N9 virus challenge, in both pre- and postexposure administration regimens. Altogether, this work demonstrates the feasibility of rapid isolation of neutralizing H7N9 antibodies from infected patients and provides a potential prophylactic and therapeutic agent against H7N9 viruses.

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