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1.
J Agric Food Chem ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32031793

RESUMO

Monosaccharides play important roles in the growth and development of plants, and their biofunctions are closely related to their endogenous contents. Therefore, the determination of monosaccharides is beneficial for the further study of monosaccharides biofunction. In this work, we developed a rapid and automatic method for the determination of 16 monosaccharides based on liquid chromatography-mass spectrometry assisted by post-column derivatization technique (LC-PCD-MS). In our method, 4-benzylaminobenzeneboronic acid (4-PAMBA) was employed as the derivatization reagent to improve the MS detection sensitivity of monosaccharides. The developed LC-PCD-MS method integrates LC separation, chemical derivatization, and MS detection in one run, thus greatly reducing the analysis time for each sample. The LODs and LOQs for 16 monosaccharides were in the range of 0.002 ng/mL-0.1 ng/mL and 0.007 ng/mL-0.5 ng/mL, respectively. Good linearity was obtained from the linear regression with determination coefficient (R2) ranging from 0.9928 to 1.0000. The relative recoveries were in the range of 80.7-117.8% with the intra- and inter-day relative standard deviations (RSDs) less than 19.7% and 16.5%, respectively, indicating good accuracy and reproducibility of the method. Finally, the method was successfully applied to investigate the spatial and temporal distribution of 16 monosaccharides in developing flower and germinating seed of A. thaliana.

2.
Biosci Rep ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003781

RESUMO

OBJECTIVE: To study the effect of puerarin on electrophysiology using a hypertrophic cardiomyocyte (HC) model. MATERIALS AND METHODS: Human urine epithelial cells were used to generate the HC model (hiPSC-CM). Cardiomyocyte hypertrophy was induced by applying 10 nM endothelin-1 (ET-1). The effects of puerarin pre-treatment (PPr) and post-treatment (PPo) on action potential, sodium current (INa) activation and inactivation, and recovery following INa inactivation were tested using patch clamp electrophysiology. RESULTS: Depolarization to repolarization 50% time (APD50) and repolarization 30% time (APD30) were significantly prolonged in the PPo and PPr groups compared to the controls. However, there were no significant differences in the action potential depolarization amplitude (APA) or the maximum depolarization velocity (Vmax) in phase 0. The PPr group had a slightly shortened APD90, and an extended APD50 and APD30, but did not exhibit any significant changes in stage A of APA and Vmax. The PPo group did not exhibit any significant changes in INa, while 12 hours of PPr improved INa. However, puerarin did not significantly affect the activation, inactivation, or recovery of the sodium channel. CONCLUSIONS: Cardiomyocyte hypertrophy significantly decreased the Vmax of the action potential and the peak density of INa. PPr inhibited the decrease of Vmax and increased the peak density of INa. Thus, puerarin could be used to stabilize the electrophysiological properties of hypertrophic cardiomyocytes and reduce arrhythmias.

3.
Neurol Sci ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912337

RESUMO

BACKGROUND: Late-onset myasthenia gravis (LOMG) is one of the major subgroups of the MG. Intensive evidence suggested that polymorphisms in HLA-DRB1 gene were associated with LOMG risk, but the results remained inconsistent. Therefore, a meta-analysis is conducted to make a more precise evaluation between HLA-DRB1 alleles and LOMG. METHODS: The PubMed, EMBASE, Cochrane library, Chinese National Knowledge Infrastructure (CNKI), and Wan Fang and Technology of Chongqing (VIP) Database were searched for eligible studies. The pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were applied to assess the association between HLA-DRB1 alleles and LOMG. RESULTS: A total of 11 studies involving 5513 people were included in our meta-analysis. The results showed that DRB1 07 and 0403 alleles were risk factors for LOMG (1.83 [1.12, 2.98], P = 0.02; 7.05 [2.62, 18.92], P = 0.0001, respectively), while DRB1 0301 and 1301 alleles were identified as protective factors for LOMG (0.44 [0.31, 0.62], P < 0.00001; 0.38 [0.23, 0.62], P = 0.0001, respectively). As for the HLA-DRB1 04 and 14 alleles, our subgroup analysis showed that there were significant associations between these alleles and LOMG in Caucasians (2.21 [1.14, 4.27], P = 0.02; 2.82 [1.29, 6.14], P = 0.009, respectively). CONCLUSIONS: These results confirmed the association of DRB1 alleles (0301, 04, 0403, 07, 1301, and 14) and LOMG, which might provide potential promising biomarkers for prediction of LOMG risk.

4.
J Immunother Cancer ; 8(1)2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31959726

RESUMO

BACKGROUND: Although clear cell renal cell carcinoma (ccRCC) is well known as a highly immunogenic tumor, only a small subset of patients could benefit from current immunotherapy, which might be due to the heterogeneity of immune microenvironment in ccRCC. So, it is meaningful to explore novel immunotherapy or combination therapy for improving therapeutic efficacy. HHLA2, a newly discovered B7 family member, is prevalently expressed in numerous tumors, including ccRCC. This study aimed to investigate the prognostic impact of HHLA2/PD-L1 co-expression and its relationship with tumor-infiltrating lymphocytes (TILs). METHODS: The expression levels of HHLA2, PD-L1, CD8, and CD4 in cancer tissues from cases (206 in the training cohort and 197 in the validation cohort) with surgically resectable primary ccRCC were evaluated by immunohistochemistry. RESULTS: The positive rates of HHLA2 were much higher than those of PD-L1 in ccRCC tissues. HHLA2-positive expression was significantly associated with necrosis, microvascular invasion, advanced Fuhrman nuclear, and TNM stage and indicated a shorter progression-free survival (PFS) and overall survival (OS) in both cohorts. Moreover, patients with HHLA2/PD-L1 co-expression suffered the highest risk of disease progression and death by a significant margin. Besides, HHLA2/PD-L1 co-expression was significantly associated with a high density of CD8+ and CD4+ TILs. Notably, a new immune classification, based on HHLA2/PD-L1 co-expression and TILs, successfully stratified PFS and OS, especially in patients with TILs positivity. CONCLUSIONS: The expression of HHLA2 is more frequent than PD-L1 in ccRCC. HHLA2/PD-L1 co-expression had an adverse impact on the prognoses of patients with ccRCC; this finding provides a rationale for combination immunotherapy with anti-HHLA2 and PD-L1 blockage for patients with ccRCC in the future.

5.
Soft Matter ; 16(1): 270-275, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31782471

RESUMO

The robust cell-in-shell structure is highly desirable for endowing living cells with an artificial exoskeleton to defend them from many environmental factors such as osmotic pressure, shear force, heat, UV radiation, and enzymes. Cell encapsulation has shown potential applications in many fields and attracted increasing interest. However, the influences of the precursors on the cell viability during the shell formation process are not clear and seldom investigated. Here, zinc nitrite, zinc acetate and zinc sulfate were applied individually to synthesize zeolitic imidazolate framework-8 (ZIF-8) shells on living cells. All the zinc salt precursors could convert to a ZIF-8 layer on the living cell surface. The zinc salts and organic ligand did not exhibit obvious toxicity to yeast cells when applied individually. However, dead cells were observed during the living cell encapsulation process using different zinc precursors. Compared with zinc nitrate and zinc acetate, ZIF-8 formed by zinc sulfate led to a higher percentage of cell death, especially under high concentrations of zinc sulfate. Cell division was suppressed by the ZIF-8 shell but restored fully upon shell removal by EDTA solution or pH 4.0 buffer. Escherichia coli (E. coli) cells showed a lower percentage of cell death, indicating excellent tolerance to the ZIF-8 encapsulation process. This work illustrates the cell toxicity during the formation of ZIF-8 cell shells by different zinc salts and engineering of the cell growth by MOF coating, which could provide a foundation for further quantitative analysis and potential applications in biomedicine and bioengineering.

6.
Int J Clin Oncol ; 25(2): 338-346, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31720994

RESUMO

OBJECTIVE: PBRM1, located on 3p21, functions as a tumor suppressor and somatic mutation of PBRM1 is frequent in clear cell renal cell carcinoma (ccRCC). This study aims to determine the influence of PBRM1 expression on the prognosis of patients with mRCC receiving tyrosine kinase inhibitor (TKI) treatment. METHODS: We identified 116 mRCC patients who were administered sunitinib or sorafenib as first-line therapy, between January 2006 and December 2016 at our institution. PBRM1 expression was assessed by immunohistochemistry. The Kaplan-Meier method was used to estimate the progression-free survival (PFS) and overall survival (OS), log-rank test was used to compare the survival outcomes between patients with low and high PBRM1 expression levels, and the Cox proportional hazard regression model was used to estimate the prognostic value. Prognostic accuracy was determined using Harrell concordance index, and nomograms were built to evaluate the prognosis of mRCC. RESULTS: Patients with low PBRM1 expression had significantly shorter median PFS (9 vs 26 months, P < 0.001) and OS (21 vs 44 months, P < 0.001) than those with high expression. Multivariate analysis showed that PBRM1 expression was an independent predictor of PFS (HR 1.975, P = 0.013) and OS (HR 2.282, P = 0.007). The model built by the addition of PBRM1 improved the C-index of PFS and OS to 0.72 and 0.82, respectively. CONCLUSIONS: The expression of PBRM1 could be a significant prognostic factor for mRCC patients treated with targeted therapy, and it increases the prognostic accuracy of the established prognostic model.

7.
Int J Cancer ; 146(7): 2027-2035, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693169

RESUMO

The heterogeneities of colorectal cancer (CRC) lead to staging inadequately of patients' prognosis. Here, we performed a prognostic analysis based on the tumor mutational profile and explored the characteristics of the high-risk tumors. We sequenced 338 colorectal carcinomas as the training dataset, constructed a novel five-gene (SMAD4, MUC16, COL6A3, FLG and LRP1B) prognostic signature, and validated it in an independent dataset from The Cancer Genome Atlas (TCGA). Kaplan-Meier and Cox regression analyses confirmed that the five-gene signature is an independent predictor of recurrence and prognosis in patients with Stage III colon cancer. The mutant signature translated to an increased risk of death (hazard ratio = 2.45, 95% confidence interval = 1.15-5.22, p = 0.016 in our dataset; hazard ratio = 4.78, 95% confidence interval = 1.33-17.16, p = 0.008 in TCGA dataset). RNA and bacterial 16S rRNA sequencing of high-risk tumors indicated that mutations of the five-gene signature may lead to intestinal barrier integrity, translocation of gut bacteria and deregulation of immune response and extracellular related genes. The high-risk tumors overexpressed IL23A and IL1RN genes and enriched with cancer-related bacteria (Bacteroides fragilis,Peptostreptococcus, Parvimonas, Alloprevotella and Gemella) compared to the low-risk tumors. The signature identified the high-risk group characterized by gut bacterial translocation and upregulation of interleukins of the tumor microenvironment, which was worth further researching.

8.
J Alzheimers Dis ; 73(2): 759-768, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31839612

RESUMO

White matter hyperintensities (WMHs), mainly caused by cerebrovascular injury, may lead to cognitive impairment. In order to identify whether the volume of WMHs is associated with cognitive decline over years, this longitudinal study involved 818 individuals from the ADNI-2 dataset from August 2010 to May 2017. Cross-sectional and longitudinal associations of WMHs with 8 cognitive domains were explored, using Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Clinical Dementia Rating Sum of Boxes (CDRSB), Alzheimer Disease Assessment Scale-Cognitive (ADAS-Cog13), Rey Auditory Verbal Learning Test (RAVLT), Functional Assessment Questionnaire (FAQ), executive function (ADNI-EF), and memory function (ADNI-Mem). The association analyses were performed using multiple linear regression models, linear mixed models, Spearman rank correlation, and Kaplan-Meier survival curves. The volumes of WMHs were greater in patients with Alzheimer's disease (AD) dementia compared with controls (p < 0.001) and mild cognitive impairment (p = 0.006) patients at baseline. The bigger volumes of WMHs correlated with worse performances on ADAS-Cog13 and ADNI-EF (p = 0.029; p = 0.003) at baseline and MMSE, MoCA, CDRSB, ADAS-Cog13, FAQ, and ADNI-Mem (overall p < 0.05) longitudinally, after adjusting for age, sex, educational level, apolipoprotein E ɛ4 genotype, hypertension, hyperlipidemia, diabetes, smoking, infarction, and diagnosis. Additionally, the correlations between the change rate of WMHs and change rates of MMSE, MoCA, CDRSB, FAQ, ADNI-EF, and ADNI-Mem were statistically significant. Furthermore, patients with high WMH volumes showed an increased likelihood of dementia. The results of the study suggest that WMH volume is associated with cognitive decline, and it contributes to the conversion to AD.

9.
Neurotox Res ; 37(1): 146-155, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31209788

RESUMO

Cerebral microbleeds are the presence of a group of pathological processes affecting the small arteries, arterioles, capillaries, and venules of the brain. Previous studies showed that cerebral microbleeds were associated with higher risk of dementia and stroke. We conducted a genome-wide association study of cerebral microbleeds to identify novel loci associated with the presence and progression of cerebral microbleeds. This study included 454 individuals composed by 176 subjects with cerebral microbleeds and 278 subjects without cerebral microbleeds in a non-Hispanic/Latino white population. Association of genetic variants with the presence and progression of cerebral microbleeds was assessed by logistic regression model. Potential genetic risk variants Apolipoprotein E (ApoE) polymorphisms were independently genotyped and checked the association with the presence and progression of cerebral microbleeds. No single-nucleotide polymorphisms (SNPs) associated with the presence or progression of cerebral microbleeds were identified at genome-wide significant level (P < 1 × 10-8). A total of 19 SNPs were associated with the presence of microbleeds at suggestive level (P < 1 × 10-5). One SNP was associated with lower progression risk for cerebral microbleeds with suggestive evidence (P < 1 × 10-5). ApoE ε4ε4 was independently associated with the presence and progression of cerebral microbleeds (odds ratio = 2.54, 95% confidence interval 1.08-6.00 and odds ratio = 5.1, 95% confidence interval 1.36-19.16). We highlighted 19 novel SNPs associated with the presence of cerebral microbleeds and one novel SNP associated with the progression of cerebral microbleeds for the first time. ApoE ε4ε4 was confirmed independently associated with the presence and progression of cerebral microbleeds.

10.
Anal Chem ; 92(2): 1916-1924, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31874562

RESUMO

Precise control over the composition, morphology, and size of porphyrin-based metal-organic frameworks is challenging, but the extension of these hybrid materials will enable the creation of novel electrochemiluminescence (ECL) emitters. The coordination of various entities is made from Zn2+ ions and meso-tetra(4-carboxyphenyl)porphine (TCPP), modulated by both solvent and bathophenanthrolinedisulfonic acid disodium salt (BPS) as capping agent, resulting in limited crystal growth of Zn-TCPP in DMF/H2O (v/v, 1:1) and the formation of nanoscale TCPP-Zn-BPS. The role of BPS is also evaluated using Zn-TCPP and BPS-Zn-TCPP as controls, prepared in the absence of BPS and different coordinating sequences of ligands, respectively. The newly obtained TCPP-Zn-BPS exhibits a variety of different morphologies, as well as spectral and optoelectronic properties. The ECL behavior of TCPP-Zn-BPS is investigated by using H2O2 as co-reactant. The amplification of ECL is further studied by ECL spectroscopies and cyclic voltammetry, with the corresponding mechanism proposed.

11.
J Am Chem Soc ; 141(51): 20451-20459, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31790227

RESUMO

Oxygen-containing groups on carbon materials can induce high catalytic activity for some reactions. Herein, on the basis of a series of metal-free single-layer graphene nanodisks (GNDs) with different surface contents of oxygen-containing groups for highly efficient electrocatalytic reduction reaction of CO2 (CO2RR) to produce formate (HCOO-), we find that the CO2RR catalytic performance is only positively correlated with the surface content of carboxyl groups. While significantly, the density functional theory calculations demonstrate that the observed high CO2RR catalytic activity originates not from the solo carboxyl or other oxygen-containing groups, but from the synergistic effect between carboxyl groups and adjacent other types of groups (namely, hydroxyl, epoxide, and carbonyl) on GNDs. Inspired by such new knowledge, we further find that if the GND catalyst can "alternate work with rest", its electrocatalytic activity for CO2RR can be regenerated cyclically via a simple electro-oxidation method to regenerate the surface carboxyl groups, achieving a remarkable long-term durability for CO2RR. Such work deepens our understanding of the role of oxygen-containing groups in catalysis and provides a new strategy for the design and synthesis of high-performance metal-free carbon-based catalysts.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1919-1924, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839060

RESUMO

OBJECTIVE: To investigate the common genotypes of thalassemia of the pregnant woman in Wuhan area of China, and to make the prenantal gentic diagnosis for the fetus at high risk of thalassemia. METHODS: A total of 357 pregnant woman with the primary positive screening in Wuhan area were included in this study. Genotypes were measured with PCR-flow cytometry, and fluorescence hybridization was used for detecting thalassmia gene. The husbands of the pregnant women with thalassmia were recalled for genetic analysis of thalassemia, and 9 cases of fetuses with high risk of thalassemia were detected by amniocontesis after genetic counseling. RESULTS: In 357 cases of the pregnant women in Wuhan area, the 214 cases were diagnosed as thalassemia, 80 cases were diagnosed as alpha thalassemia (up to 90%), whose genotypes were determind as --SEA/αα (78.75%) and -α3.7/αα (15.00%), while 133 cases were determind with genotype of IVS-2-654/N (43.61%), CD41-42/N (20.30%) and CD17/N (19.55%) in beta thalassemia (up to 80%). 9 prenatal diagnosis continued pregnancy included 1case of -α3.7/--SEA, 1 case of -α3.7/αα, 2 cases of --SEA/αα, 2 cases of IVS-2-654/N and 3 cases of normal, however, the pregnancy in prenatal diagnosis of -α3.7/--SEA voluntarily was terminated after genetic counseling. Follow-up results after delivery were consistent with prenatal diagnosis. CONCLUSION: Minor and static thalassemia were very common in Wuhan area. Genetic detection after primary screening, genetic counseling and prenatal diagnosis in pregnant women could provide a theoretical basis for the development of regional specific prevention of intermedius and critical thalassemia which is meaning for rearing and bearing better children.


Assuntos
Talassemia alfa , Talassemia beta , China , Feminino , Testes Genéticos , Genótipo , Humanos , Gravidez , Diagnóstico Pré-Natal
13.
Cancer Med ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31840409

RESUMO

Neuroendocrine tumors (NETs) are heterogeneous, and the incidence of NETs is rapidly increasing. We observed different survival in patients with rectal NETs and rectosigmoid junction NETs, which are treated similarly. We included patients with rectal and rectosigmoid junction NETs from the SEER database. The 5-year survival was set as the end-point. 6675 patients with rectal NETs and 329 patients with rectosigmoid junction NETs, were eligible for the analysis. Initially, the survival analyses suggested that the 5-year survival significantly differed between the patients with rectal and rectosigmoid junction NETs (HR = 0.82, 95% CI 0.70-0.95; P = .01). Tumor differentiation, an invasion deeper than T2, and lymph node and distant metastases were still important risk factors affecting survival for both location. While, the males showed better survival (HR = 0.69, 95% CI 0.55-0.88; P < .01) and primary tumor surgery had no benefits (P = .56) for patients with rectosigmoid junction NETs. The factors that predict regional lymph node metastases varied by location. In rectal NETs, invasion deeper than T1 and a tumor larger than 1 cm could significantly increase the risk of regional lymph node metastases (all OR > 5, P < .01). In rectosigmoid junction NETs, the risk of regional lymph node metastases was considered significantly higher with invasion deeper than T1 (all OR > 5, P < .01) and a tumor larger than 2 cm (OR = 31.32, 95% CI 2.53-387.57; P < .01). We advocate a clear and consistent definition of the rectosigmoid junction for future studies, and more studies are needed to determine the reason underlying differences between rectum and rectosigmoid junction.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31760433

RESUMO

BACKGROUND: Consolation is a type of empathy-like behavior that has recently been observed in some socially living rodents. Despite the growing body of literature suggesting that stress affects empathy, the relationship between stress and consolation remains understudied at the preclinical level. Here, we examined the effects of chronic emotional stress (ES) or physical stress (PS) exposure on consolation and emotional behaviors by using the socially monogamous mandarin vole (Microtus mandarinus) in both males and females. METHOD/RESULTS: PS-voles were exposed to 14-day social defeat stress, whereas ES-voles vicariously experienced the defeat of their partners. We found that PS- but not ES-voles showed reduced grooming toward their defeated partners and increased anxiety- and despair-like behaviors. Meanwhile, PS-voles exhibited decreased neural activity in the anterior cingulate cortex (ACC), which is centrally involved in empathy. The densities of oxytocin receptors (OTRs), dopamine D2 receptors (D2Rs) and serotonin 1A-receptors (5-HT1ARs) within the ACC were significantly decreased in the PS group compared with controls. All the behavioral and physiological changes were similar between the sexes. Finally, we found that the reduced consolation behavior and some anxiety-like syndromes in PS-voles could be alleviated by pretreatment with an OTR, D2R or 5-HT1AR agonist within the ACC, whereas injections of corresponding receptor antagonists to the control voles decreased the consolation behavior and increased some anxiety-like behaviors. CONCLUSIONS: Our results indicated that chronic PS exposure impaired consolation and induced anxiety-like behaviors in mandarin voles and OTRs, 5-HT1ARs and D2Rs within the ACC may play important roles in these processes.

15.
Opt Lett ; 44(21): 5262-5265, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674983

RESUMO

Polarization modulation plays a key role in polarization-encoding quantum key distribution (QKD). Here, we report a new, to the best of our knowledge, polarization modulation scheme based on an inherently stable Sagnac interferometer. The presented scheme is free of polarization mode dispersion and calibration as well as insensitive to environmental influences. Successful experiments at a repetition frequency of 1.25 GHz have been conducted to demonstrate the feasibility and stability of the scheme. The measured average quantum bit-error rate of the four polarization states is as low as 0.27% for 80 consecutive minutes without any adjustment. This high-speed intrinsically stable polarization modulation can be widely applied to many polarization-encoding QKD systems, such as BB84, MDI, etc.

16.
J Exp Bot ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701152

RESUMO

The critical functions of 2-oxoglutarate-dependent dioxygenase (2OGD) for the metabolism of salicylic acid (SA) in plants have been demonstrated, yet, the role of 2OGD in SA biosynthesis is poorly understood. Here, we report that two dioxygenase-encoding genes, SLC1 (slender and crinklyleaf 1) and SLC2 (slender and crinklyleaf 2), play essential roles in shoot development and SA production in rice (Oryza sativa). Overexpression of SLC1 (SLC1-OE) or SLC2 (SLC2-OE) in rice produced bizarre infertile plants with slender and crinkly leaves. Disruption of SLC1 or SLC2 led to dwarf plants. Down-regulation of SLC1 and SLC2 at the same time in the SLC1-SLC2 RNAi lines resulted in a severe defect in early leaf development. Enhanced SA level in the SLC1-OE plants and decreased SA level in the slc1 and slc2 mutants were scored. Accordingly, altered expression level of a set of SA-related genes in plants of SLC1-OE, slc1 and slc2 mutants was observed. The results from exploring the putative interacting proteins for SLC1 indicated that, either the KNOX1- or ELK-domain of OSH1 (homeobox1) is sufficient for accomplishing the interaction between SLC1 and OSH1. Collectively, our data revealed the importance of SLC1 and SLC2 in the shoot development of rice.

17.
Int J Mol Sci ; 20(20)2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31635144

RESUMO

Strain GA A07 was identified as an intestinal Bacillus bacterium of zebrafish, which has high efficiency to biotransform the triterpenoid, ganoderic acid A (GAA), into GAA-15-O-ß-glucoside. To date, only two known enzymes (BsUGT398 and BsUGT489) of Bacillus subtilis ATCC 6633 strain can biotransform GAA. It is thus worthwhile to identify the responsible genes of strain GA A07 by whole genome sequencing. A complete genome of strain GA A07 was successfully assembled. A phylogenomic analysis revealed the species of the GA A07 strain to be Bacillus thuringiensis. Forty glycosyltransferase (GT) family genes were identified from the complete genome, among which three genes (FQZ25_16345, FQZ25_19840, and FQZ25_19010) were closely related to BsUGT398 and BsUGT489. Two of the three candidate genes, FQZ25_16345 and FQZ25_19010, were successfully cloned and expressed in a soluble form in Escherichia coli, and the corresponding proteins, BtGT_16345 and BtGT_19010, were purified for a biotransformation activity assay. An ultra-performance liquid chromatographic analysis further confirmed that only the purified BtGT_16345 had the key biotransformation activity of catalyzing GAA into GAA-15-O-ß-glucoside. The suitable conditions for this enzyme activity were pH 7.5, 10 mM of magnesium ions, and 30 °C. In addition, BtGT_16345 showed glycosylation activity toward seven flavonoids (apigenein, quercetein, naringenein, resveratrol, genistein, daidzein, and 8-hydroxydaidzein) and two triterpenoids (GAA and antcin K). A kinetic study showed that the catalytic efficiency (kcat/KM) of BtGT_16345 was not significantly different compared with either BsUGT398 or BsUGT489. In short, this study identified BtGT_16345 from B. thuringiensis GA A07 is the catalytic enzyme responsible for the 15-O-glycosylation of GAA and it was also regioselective toward triterpenoid substrates.

19.
Cells ; 8(10)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31575017

RESUMO

Long non-coding RNAs (lncRNAs) are versatile regulators of gene expression and play crucial roles in diverse biological processes. Epithelial-mesenchymal transition (EMT) is a cellular program that drives plasticity during embryogenesis, wound healing, and malignant progression. Increasing evidence shows that lncRNAs orchestrate multiple cellular processes by modulating EMT in diverse cell types. Dysregulated lncRNAs that can impact epithelial plasticity by affecting different EMT markers and target genes have been identified. However, our understanding of the landscape of lncRNAs important in EMT is far from complete. Here, we summarize recent findings on the mechanisms and roles of lncRNAs in EMT and elaborate on how lncRNAs can modulate EMT by interacting with RNA, DNA, or proteins in epigenetic, transcriptional, and post-transcriptional regulation. This review also highlights significant EMT pathways that may be altered by diverse lncRNAs, thereby suggesting their therapeutic potential.

20.
Science ; 366(6461): 132-135, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31604316

RESUMO

Quantum mechanics and the general theory of relativity are two pillars of modern physics. However, a coherent unified framework of the two theories remains an open problem. Attempts to quantize general relativity have led to many rival models of quantum gravity, which, however, generally lack experimental foundations. We report a quantum optical experimental test of event formalism of quantum fields, a theory that attempts to present a coherent description of quantum fields in exotic spacetimes containing closed timelike curves and ordinary spacetime. We experimentally test a prediction of the theory with the quantum satellite Micius that a pair of time-energy-entangled particles probabilistically decorrelate passing through different regions of the gravitational potential of Earth. Our measurement results are consistent with the standard quantum theory and hence do not support the prediction of event formalism.

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