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1.
Chemistry ; 30(6): e202302982, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38031382

RESUMO

Poly (triazine imide) (PTI) generally obtained via ionothermal synthesis features extended π-conjugation and enhanced crystallinity. However, in-depth investigation of the polycondensation process for PTI is an onerous task due to multiple influencing factors and limited characterization techniques. Herein, to simplify the polymerization route and exclude non-essential factors, PTI was prepared by calcining only melamine and LiCl. This study aims to identify the pivotal role of LiCl in PTI formation, which can convert heptazine-based intermediates into more stable triazine-based PTI framework. Based on this discovery, we demonstrate the transformation process of the prepared samples from amorphous Bulk g-C3 N4 to regular PTI, and further prove that the reaction with LiCl causes disruption of heptazine covalent organic frameworks. Additionally, the PTI exhibits higher photocatalytic water splitting performance due to efficient charge carrier mobility and separation, as well as faster reaction kinetics. This discovery deepens understanding of the polycondensation process of PTI crystals and provides insights toward the rational design of crystalline carbon nitride-based semiconductors.

2.
Langmuir ; 40(23): 12179-12190, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38809579

RESUMO

As haloanilines (HANs) are important organic intermediates and fine chemicals, their preparation over non-noble-metal-based catalysts by catalytic hydrogenation has attracted wide attention. However, the reaction suffers from relatively harsh conditions. Herein, we found that a 3.5%Ni/P25 catalyst exhibited superior photo-thermal catalytic activity with a TOFs of 5207 h-1 for hydrogenation of p-chloronitrobenzene (p-CNB) to p-chloroaniline under a 300 W full spectrum, which was much higher than that of photo- and thermal catalysis alone. Moreover, the 3.5%Ni/P25 catalyst could be recycled 4 times and was effective for the hydrogenation of various halonitrobenzenes (HNBs) with superior selectivity. Furthermore, the kinetic research showed that the excellent catalytic performance could be attributed to the better activation and dissociation of H2 by photo-thermal catalysis and the hydrogenation of p-CNB obeyed the condensation routine by ionic hydrogenation over 3.5%Ni/P25.

3.
J Oral Pathol Med ; 53(6): 393-403, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38777565

RESUMO

OBJECTIVE: This Bayesian network meta-analysis was performed to analyze the associations between clinicopathological characteristics and BRAF mutations in ameloblastoma (AM) patients and to evaluate the diagnostic accuracy. MATERIALS AND METHODS: Four electronic databases were searched from 2010 to 2024. The search terms used were specific to BRAF and AM. Observational studies or randomized controlled trials were considered eligible. The incidence of BRAF mutation and corresponding clinicopathological features in AM patients were subjected to Bayesian network analyses and diagnostic accuracy evaluation. RESULTS: A total of 937 AM patients from 20 studies were included. The pooled prevalence of BRAF mutations in AM patients was 72%. According to the Bayesian network analysis, BRAF mutations are more likely to occur in younger (odds ratio [OR], 2.3; credible interval [CrI]: 1.2-4.5), mandible site (OR, 3.6; 95% CrI: 2.7-5.2), and unicystic (OR, 1.6; 95% CrI: 1.1-2.4) AM patients. Similarly, higher diagnostic accuracy was found in the younger, mandible, and unicystic AM groups. CONCLUSIONS: The incidence, risk, and diagnostic accuracy of BRAF mutation in AM were greater in younger patients, those with mandible involvement, and those with unicystic AM than in patients with other clinicopathological features. In addition, there was a strong concordance in the diagnostic accuracy between molecular tests and immunohistochemical analysis.


Assuntos
Ameloblastoma , Teorema de Bayes , Mutação , Proteínas Proto-Oncogênicas B-raf , Ameloblastoma/genética , Ameloblastoma/patologia , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Maxilomandibulares/genética , Neoplasias Maxilomandibulares/patologia , Metanálise em Rede , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
4.
Environ Res ; 242: 117775, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029815

RESUMO

The development of cost-efficient biochar adsorbent with a simple preparation method is essential to constructing efficient wastewater treatment system. Here, a low-cost waste carton biochar (WCB) prepared by a simple two-step carbonization was applied in efficiently removing Rhodamine B (RhB) in aqueous environment. The maximum ability of WCB for RhB adsorption was 222 mg/g, 6 and 10 times higher than both of rice straw biochar (RSB) and broadbean shell biochar (BSB), respectively. It was mainly ascribed to the mesopore structure (3.0-20.4 nm) of WCB possessing more spatial sites compared to RSB (2.2 nm) and BSB (2.4 nm) for RhB (1.4 nm✕1.1 nm✕0.6 nm) adsorption. Furthermore, external mass transfer (EMT) controlled mass transfer resistance (MTR) of the RhB sorption process by WCB which was fitted with the Langmuir model well. Meanwhile, the adsorption process was dominated by physisorption through van der Waals forces and π-π interactions. A mixture of three dyes in river water was well removed by using WCB. This work provides a straightforward method of preparing mesoporous biochar derived from waste carton with high-adsorption capacity for dye wastewater treatment.


Assuntos
Carvão Vegetal , Águas Residuárias , Poluentes Químicos da Água , Corantes/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Poluentes Químicos da Água/análise , Cinética
5.
Dermatology ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852575

RESUMO

INTRODUCTION: Despite numerous treatment options for Nail lichen planus (NLP), a validated method for measuring the severity of NLP and therapeutic response in clinical trials is absent. To develop and validate a measurement instrument (tNLPSI - typical nail lichen planus severity index) for typical nail lichen planus that could be used in clinical trials. METHODS: 48 patients with typical NLP diagnosed pathologically and 5 dermatologists participated. The physicians were trained to use the tNLPSI activity scale and Physician's Global Assessment (PGA). Using both tools, 5 physicians scored samples independently to estimate inter-rater reliability and intra-rater reliability in two sessions. In addition, tNLPSI activity scores were compared with physician global assessment (PGA) scores. RESULTS: The tNLPSI activity scale had excellent internal consistency and interrater reliability (Cronbach's alpha 0.990; ICC= 0.954; 95% CI= 0.930-0.971), and the correlations between the different graders' scores indicate good consistent (rp=0.934-0.968. In addition, the tNLPSI activity scale demonstrated high intra-rater reliability (ICC=0.996; 95% CI= 0.993-0.998), showing good reproducibility. And tNLPSI activity scores and PGA scores showed good construct validity (Spearman's rho= 0.941 and Spearman's rho= 0.903-0.935, respectively; P < 0.01). CONCLUSIONS: The tNLPSI activity scale was demonstrated to be consistent, reliable, reproducible, and feasible. It may prove to be a valuable tool in evaluating the treatment response in typical NLP clinical trials.

6.
BMC Med Educ ; 24(1): 655, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862948

RESUMO

BACKGROUND: The COVID-19 pandemic rapidly altered dental practice, training, and education. This study investigates the pandemic's impacts on the clinical training experiences of dental and dental hygienist trainees at the US Department of Veterans Affairs (VA). METHODS: Using data from post-doctoral general practice dentists, dental specialists, and dental hygienist trainees who completed the VA Trainee Satisfaction Survey before and during COVID-19, we performed logistic regression and thematic content analyses to determine whether COVID-19 was associated with training satisfaction and likelihood of considering future VA employment. RESULTS: While post-doctoral dentist and dental specialty trainees did not report significant differences, dental hygienist trainees reported increased overall satisfaction and an increased likelihood to consider future VA employment during the pandemic compared to before the pandemic. Similar reasons for dissatisfaction were identified for both the pre-pandemic and pandemic groups. CONCLUSIONS: Research outside VA indicates the pandemic's association with trainees' intentions to leave health profession education programs. Our results suggest the likely existence of factors that could lead to positive changes for at least some portion of the dental workforce. Future studies should explore those potential factors as some may be replicable in other settings or may apply to other health professions.


Assuntos
COVID-19 , Higienistas Dentários , United States Department of Veterans Affairs , Humanos , COVID-19/epidemiologia , Estados Unidos/epidemiologia , Higienistas Dentários/educação , Higienistas Dentários/psicologia , Masculino , Feminino , Satisfação Pessoal , Adulto , Pandemias , SARS-CoV-2 , Inquéritos e Questionários , Odontólogos/psicologia
7.
Osteoporos Int ; 34(8): 1465-1476, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37204453

RESUMO

This study revealed that there was no significant linear relationship between fasting C-peptide (FCP) level and bone mineral density (BMD) or fracture risk in type 2 diabetes mellitus (T2DM) patients. However, in the FCP ≤ 1.14 ng/ml group, FCP is positively correlated with whole body (WB), lumbar spine (LS), and femoral neck (FN) BMD and negatively correlated with fracture risk. PURPOSE: To explore the relationship between C-peptide and BMD and fracture risk in T2DM patients. METHODS: 530 T2DM patients were enrolled and divided into three groups by FCP tertiles, and the clinical data were collected. BMD was measured by dual-energy X-ray absorptiometry (DXA). The 10-year probability of major osteoporotic fractures (MOFs) and hip fractures (HFs) was evaluated by adjusted fracture risk assessment tool (FRAX). RESULTS: In the FCP ≤ 1.14 ng/ml group, FCP level was positively correlated with WB, LS, and FN BMD, while FCP was negatively correlated with fracture risk and osteoporotic fracture history. However, FCP was not correlated with BMD and fracture risk and osteoporotic fracture history in the 1.14 < FCP ≤ 1.73 ng/ml and FCP > 1.73 ng/ml groups. The study has shown that FCP was an independent factor influencing BMD and fracture risk in the FCP ≤ 1.14 ng/ml group. CONCLUSIONS: There is no significant linear relationship between FCP level and BMD or fracture risk in T2DM patients. In the FCP ≤ 1.14 ng/ml group, FCP is positively correlated with WB, LS, and FN BMD and negatively correlated with fracture risk, and FCP is an independent influencing factor of BMD and fracture risk. The findings suggest that FCP may predict the risk of osteoporosis or fracture in some T2DM patients, which has a certain clinical value.


Assuntos
Diabetes Mellitus Tipo 2 , Osteoporose , Fraturas por Osteoporose , Humanos , Densidade Óssea , Fraturas por Osteoporose/complicações , Diabetes Mellitus Tipo 2/complicações , Peptídeo C , Osteoporose/complicações , Absorciometria de Fóton , Fatores de Risco , Medição de Risco
8.
Mol Cell Biochem ; 478(2): 407-414, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35838912

RESUMO

Long non-coding RNAs (lncRNAs) regulate gene expression and play a significant role in cancer progression. Previously, downregulation of lncRNA MEG3 was shown to associate with poor clinical outcomes in melanoma patients. The basis for this association has not been described and the aims of this study were to identify a role for lncRNA MEG3 in melanoma and to describe its regulatory mechanism of action. RT-qPCR was used to detect lncRNA MEG3 expression in melanoma cells and tissues. Luciferase reporter assays were used to identify lncRNA MEG3 downstream targets. Melanoma cells were transfected with various expression vectors and these transfected cells were assessed for; migration, colony formation, proliferation, in vivo tumorigenesis, and metastatic potential. Melanoma cell lines were found to be sensitive to lncRNA MEG3 expression levels and overexpression was found to inhibit melanoma cell proliferation and invasion, both in vitro and in vivo. Luciferase reporter assays identified miR-208 and SOX4 as downstream targets of lncRNA MEG3. Overexpression of miR-208 and silencing of SOX4 rescued invasion and proliferation by cells that overexpressed lncRNA MEG3. Moreover, lncRNA MEG3 inhibited cancer stem cell differentiation and suppressed melanoma progression and metastasis through inhibition of miR-208 by SOX4.


Assuntos
Melanoma , MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação para Cima , Linhagem Celular Tumoral , Melanoma/genética , Proliferação de Células/genética , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo
9.
Org Biomol Chem ; 21(45): 8984-8988, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37937487

RESUMO

A metal-free and efficient approach for the synthesis of structurally important nicotinates through 4-HO-TEMPO-mediated [3 + 3] annulation of cyclopropanols with ß-enamine esters is presented. This protocol features high atom efficiency, green waste, simple operation and broad substrate scope. Moreover, the experiments of gram-scale synthesis and recovery of oxidants make this strategy more sustainable and practical.

10.
Phys Chem Chem Phys ; 24(42): 25767-25772, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36222115

RESUMO

As an allotrope of graphene, T-graphene was predicted to be an intrinsic two-dimensional (2D) superconductor with a superconducting critical temperature (Tc) of about 20.8 K [Gu et al., Chin. Phys. Lett. 36, 097401 (2019)]. In this work, based on first-principles calculations, hole doping and biaxial tensile strain (BTS) are considered to modulate the electron-phonon coupling (EPC) and superconductivity of T-graphene. It is found that the EPC constant of T-graphene is 0.807 and the calculated critical temperature Tc is 28.2 K at a doping level of 0.5 hole per unit cell (3.31 × 1014 cm-2) and 12% BTS. Furthermore, when 0.8 hole per unit cell (5.43 × 1014 cm-2) doping and 10% BTS are applied, the EPC constant is 0.939, and the Tc can be boosted to 35.2 K, which is higher than those of the pristine T-graphene and many other 2D carbon-based superconductors.

11.
Arch Insect Biochem Physiol ; 110(3): e21899, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35419869

RESUMO

Apriona germari is one of the most serious wood-boring pests that cause damage to economic and landscaping trees and has adapted to a wide range of plants as diet. Gut bacteria play an important role in biology and ecology of herbivores, especially in growth and adaptation. To investigate how plant hosts shape A. germari gut microbiota, A. germari larvae were collected from Populus tomentosa and Malus pumilal, and gut microbiomes were sequenced based on 16S rDNA high-throughput sequencing technology. A total of 853,424 high-quality reads were obtained and clustered into 196 operational taxonomic units under a 97% similarity cutoff, which were annotated into 8 phyla, 10 classes, 21 orders, 34 families, 59 genera, and 39 species. Gibbsiella was the most dominant genus of intestinal bacteria, followed by Enterobacter and Acinetobacter. No significant difference was observed in larvae gut bacterial richness and diversity of A. germari collected from two hosts, though alpha diversity showed that the richness of gut bacteria in A. germari larvae collected on P. tomentosa was slightly higher than that in A. germari on M. pumilal, and beta diversity showed little difference between two host plants. The functional abundance analysis of the detected bacteria revealed fermentation, chemoheterotrophy, symbionts, and nitrate relative functions that highly possibly support wood-boring beetles to feed on woody tissues. Our study provided a theoretical basis for investigating the function of intestinal symbiosis bacteria of A. germari.


Assuntos
Besouros , Microbioma Gastrointestinal , Animais , Bactérias/genética , Besouros/genética , Sequenciamento de Nucleotídeos em Larga Escala , Larva/microbiologia , RNA Ribossômico 16S/genética
12.
Asia Pac J Clin Nutr ; 31(4): 759-767, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36576293

RESUMO

BACKGROUND AND OBJECTIVES: Studies have suggested that vitamin D deficiency is associated with impaired cardiac autonomic nerve function. This study explores the correlation between serum vitamin D and cardiac autonomic neuropathy (CAN) in prediabetes and reveals the protective effect of vitamin D against CAN. METHODS AND STUDY DESIGN: In total, 113 patients with prediabetes and definite CAN and 180 with prediabetes but without CAN were enrolled on the basis of their standard cardiovascular autonomic reflex test results. Chemiluminescence was used to measure 25(OH)D, the patients with CAN were divided into four groups, and the heart rate variability (HRV) of the study groups were compared. RESULTS: Relative to the 50≤25(OH)D<75-nmol/L group, the 25≤25(OH)D<50-nmol/L and 25(OH)D<25-nmol/L groups exhibited significant differences in the time and frequency domains of HRV (p< 0.05). Furthermore, we discovered that 25(OH)D is positively correlated with standard deviation of normal-to-normal RR intervals (SDNN) (ß=0.566, p<0.05) and negatively correlated with low-to-high frequency ratio (LF/HF) (ß=-0.199, p<0.05). A logistic regression reveals that CAN in prediabetes is significantly correlated with the 25(OH)D concentrations of <25 nmol/L (OR, 2.380 [1.208-4.691]; p<0.05) and 25≤25(OH)D<50 nmol/L (OR, 1.875 [1.064-3.751]; p<0.05). CONCLUSIONS: Serum 25(OH)D is significantly correlated with CAN in prediabetes, especially in the 25(OH)D <25-nmol/L group. Therefore, vitamin D deficiency may be related to the occurrence of CAN in prediabetes, and appropriate supplementation may provide protection against CAN.


Assuntos
Estado Pré-Diabético , Deficiência de Vitamina D , Humanos , Vitamina D , Estado Pré-Diabético/complicações , Vitaminas , Frequência Cardíaca/fisiologia , Suplementos Nutricionais
13.
J Asian Nat Prod Res ; 24(11): 1018-1024, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34842008

RESUMO

Phytochemical investigation on the concentrate of Huangjing wine, resulted in the isolation of three new tyrosol derivatives 4'''-hydroxyphenethyl 2-(R)-hydroxy-3-phenylpropionate (1), 4'''-hydroxyphenethyl(4'-hydroxy-3'-methoxyphenyl)propionate (2) and 4''-hydroxyphenethyl ethyl succinate (3), together with 5 known compounds, ferulic acid (4), L-phenyllactic acid (5), hydroxytyrosol (6), dihydroferulic acid (7), cyclo(L-Pro-D-Tyr) (8). Their structures were elucidated using spectroscopic analysis and by comparison with the literature data. All compounds displayed antioxidant effect in the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical. Among them, the new compound 2 exhibited obvious antioxidant effect, and new compounds 1 and 3 exhibited medium antioxidant effect.


Assuntos
Vinho , Vinho/análise , Antioxidantes/farmacologia , Antioxidantes/química , Estrutura Molecular
14.
Bioorg Med Chem Lett ; 40: 127902, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33684439

RESUMO

Six disubstituted Schiff base compounds were synthesized (A1-A6) and characterized using infrared spectroscopy (IR), elemental analyses (EA), 1H NMR, 13C NMR and HRMS spectroscopic techniques. Crystal structure of A1 has been determined by single crystal X-ray diffraction. The antifungal activities against three fungi were assessed, and the results showed that compounds of A1 and A2 have good activity for Wheat gibberellic with EC50 value of 15.89 and 16.99 mg/L, respectively. Compounds of A3, A4 and A6 have good bioactivity against Maize rough bacteria (the value of EC50 is 8.23, 7.56 and 7.92 mg/L, respectively). According to the result of molecular docking, compounds of A1 and A2 have the smallest docking energy (-8.33, -9.00 kcal/mol). Besides, for A1 and A2, the analysis of highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) analysis and molecular electrostatic potential map were to further elaborate the reason for the good activity with density functional theory (DFT)-B3LYP/6-31G.


Assuntos
Antifúngicos/síntese química , Proteínas Fúngicas/química , Bases de Schiff/síntese química , Triazóis/química , Aminas/química , Antifúngicos/farmacologia , Cristalização , Cristalografia por Raios X , Teoria da Densidade Funcional , Conformação Molecular , Simulação de Acoplamento Molecular , Ligação Proteica , Bases de Schiff/farmacologia , Eletricidade Estática , Termodinâmica
15.
Neurol Sci ; 42(2): 697-703, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32661882

RESUMO

OBJECTIVE: To examine whether urine kynurenine (KYN) levels were associated with early-stage Parkinson's disease (PD), as well as the value of urine KYN as a potential biomarker in early-stage PD. METHOD: Eighty-two participants including 41 PD patients and 41 healthy controls were enrolled into this study. Urine KYN levels were measured with a KYN enzyme-linked immunoassay kit. In order to explore the correlation between some clinical parameters and urine KYN, the clinical parameters for these participants were recorded. Diagnostic value and clinical relevance of urine KYN were assessed by using receiver operator characteristic (ROC) curve and correlation analysis. RESULTS: Urine KYN levels were significantly higher in the PD group than in the healthy group (891.95 ± 276.65 pg/ml vs. 640.11 ± 122.37 pg/ml, p = 0.000). The correlations between urine KYN levels and clinical parameters are as follows: Hoehn-Yahr stage (r = 0.676, p = 0.000), disease duration (r = 0.772, p = 0.000), Mini-Mental State Examination scores (r = -0.434, p = 0.005). There was no statistically significant correlation between urine KYN with age, low-density cholesterol (LDL), triglycerides (TG), cholesterol (TC), homocysteine (HCY), uric acid (UA), and glomerular filtration rate (GFR). The ROC analysis showed that urine KYN optimal cutoff value of 751.88 pg/ml had a sensitivity of 65.9% and a specificity of 90.2% for distinguishing between PD and controls, with an area under the curve (AUC) of 0.776. CONCLUSION: Urine KYN were significantly associated with PD severity and mild cognitive impairment. Urine KYN may be a new biomarker for early-stage PD.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Biomarcadores , Humanos , Cinurenina , Doença de Parkinson/diagnóstico , Triglicerídeos
16.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3478-3486, 2021 Jul.
Artigo em Zh | MEDLINE | ID: mdl-34402269

RESUMO

Elaphurus davidianus( Milu),a rare animal unique to China,has been used as medicine for more than a thousand years,but the extinction of Milu in modern times resulted in the unavailability of related medical products. Today,the reintroduction of Milu population makes it possible to restore its medicinal usage. The resource reserves of Cervi Cornu,the natural shedding product from Milu,are increasing with the expansion of the population,allowing it to be fully utilized in the medical field. Mijiao Pills,first recorded in Important Prescriptions Worth a Thousand Gold for Emergency( Bei Ji Qian Jin Yao Fang) by Sun Simiao in the Tang Dynasty,is the first Chinese medicinal prescription with Cervi Cornu as the sovereign medicinal,which is effective in tonifying. Its composition,preparation,efficacy and indications,and administration are described in detail in the Important Prescriptions Worth a Thousand Gold for Emergency,which however,have changed significantly over the thousands of years,seriously affecting the clinical application of this classical prescription and related product development. Therefore,the key information of this prescription should be systematically collated and summarized. According to the principles of textual research on key information in ancient classical prescriptions promulgated by relevant authorities,this paper reviewed ancient Chinese medical books of the past dynasties,modern literature,as well as the Pharmacopoeia of the People's Republic of China( 2020 Version) to figure out such key information as the source,historical evolution,original plants and animals and their processing,dosage,preparation,and usage of Mijiao Pills. This paper aimed to provide a basis for the clinical application of Mijiao Pills and subsequent product development,thus facilitating the development and utilization of this precious medicinal animal resource.


Assuntos
Cornus , Medicina Tradicional Chinesa , Livros , China , Humanos , Prescrições
17.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3494-3503, 2021 Jul.
Artigo em Zh | MEDLINE | ID: mdl-34402271

RESUMO

In order to reveal the regional characteristics of nucleosides and amino acids in Elaphuri Davidiani Cornu,39 samples of Elaphuri Davidiani Cornu collected from 4 different regions were analyzed by UPLC-QTRAP ~®/MS2 method followed by orthogonal partial least-squares discrimination analysis( OPLS-DA) and cluster analysis( CA). The results showed all the samples contained abundant nucleosides and amino acids,with the total content of 45. 09 µg·g~(-1) and 634. 80 µg·g-1,respectively. The samples presented significant regional differences in the contents of individual components,and the main differential components included Ura,Hpro,Thr,Glu,G5 P,2'-dG,Adeno,Met,Ade,Gln,Orni,Phe,2'-dA,Hit,Lys,and Ile. Among them,Ura,Met,Glu,and Ile had the highest content in the samples from Dafeng in Jiangsu,Qinhu in Jiangsu,Beijing,and Shishou in Hubei,respectively. OPLS-DA and CA demonstrated that all the samples of Elaphuri Davidiani Cornu could be divided into three categories,reflecting the regional characteristics. The results indicated that the accumulation of nucleosides and amino acids in Elaphuri Davidiani Cornu was closely related to its habitat,providing a useful reference for the research on the quality formation,quality evaluation and control,as well as the comprehensive utilization of Elaphuri Davidiani Cornu. The findings suggested that the content factors of Ura,Met,Glu,and Ile could be included into the quality standard system of Elaphuri Davidiani Cornu as the characteristics of medicinal materials from different regions.


Assuntos
Cornus , Aminoácidos , Pequim , Nucleosídeos
18.
Ecotoxicol Environ Saf ; 205: 111152, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32846297

RESUMO

Root exudates are the most direct manifestation of the response of plants changes in the external environment. Therefore, based on non-targeted gas chromatography-time-of-flight mass spectrometry and metabolomics, the response of Sedum plumbizincicola root exudates to Cd stress was used to reveal the possible mechanism of resistance to or accumulation of Cd. The results showed that Cd significantly changed the composition and contents of S. plumbizincicola root exudates. A total of 155 metabolites were identified in S. plumbizincicola root exudates, among which 33 showed significant differences under Cd stress, including organic acids, amino acids, lipids, and polyols. Cd stress suppressed organic acid metabolism and lipid metabolism in S. plumbizincicola and significantly affected amino acid metabolism. There were 16 metabolic pathways related to Cd stress, among which arginine and proline metabolism, valine, leucine, and isoleucine biosynthesis, glycine, serine, and threonine metabolism, glutathione metabolism, and purine metabolism were the key pathways with the highest correlation, and were closely related to the stress resistance of S. plumbizincicola.


Assuntos
Cádmio/toxicidade , Metaboloma/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Exsudatos de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Sedum/efeitos dos fármacos , Poluentes do Solo/toxicidade , Adaptação Fisiológica/efeitos dos fármacos , Bioacumulação/efeitos dos fármacos , Biodegradação Ambiental , Cádmio/metabolismo , Metabolômica , Raízes de Plantas/metabolismo , Sedum/metabolismo , Poluentes do Solo/análise
19.
Mikrochim Acta ; 187(6): 333, 2020 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-32415377

RESUMO

A low-field nuclear magnetic resonance (LF-NMR) DNA-hydrogel (LNDH) nanoprobe was designed for bisphenol A (BPA) determination. It consists of Fe3O4 superparamagnetic iron oxide nanoparticles (SPIONs) and a DNA-hydrogel technology. Fe3O4 SPIONs were encapsulated in the DNA-hydrogel to form an aggregated state. After adding BPA, the gel system transformed into a sol gel due to the target-aptamer specific binding. The coated gathered particles dispersed and thus, the relaxation time T2 declined. The LNDH nanoprobe was developed to realize a simple, sensitive, and effective BPA determination method without repeated magnetic separation steps. Under the optimal experimental conditions, the determination range of the LNDH biosensor was 10-2~102 ng mL-1 and the limit of determination was 0.07 ng mL-1. The LNDH nanoprobe was applied to two kinds of water samples (tap water and bottled water). The recovery ranged from 87.85 to approximately 97.87%. This strategy offered a new method to detect BPA by LF-NMR. It is also expected to be applicable in related fields of food safety determination, environmental monitoring, and clinical diagnosis. Graphical abstract Schematic presentation of LNDH biosensor. Acrydite-modified ssDNA was copolymerized with acrylamide to form linear conjugates PS-A/B, adding aptamer and SPIONs to form DNA-hydrogel. When aptamer captured the target, the hydrogel was destroyed to disperse the coated SPIONs. T2 relaxation time declined.


Assuntos
Compostos Benzidrílicos/análise , DNA de Cadeia Simples/química , Água Potável/química , Hidrogéis/química , Nanopartículas de Magnetita/química , Fenóis/análise , Poluentes Químicos da Água/análise , Aptâmeros de Nucleotídeos/química , Compostos Benzidrílicos/química , Técnicas Biossensoriais , Limite de Detecção , Espectroscopia de Ressonância Magnética , Fenóis/química
20.
Chemphyschem ; 18(1): 55-58, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27860069

RESUMO

The intracellular milieu contains upwards of 400 g of macromolecules per liter. This crowding is thought to have a larger influence on intrinsically disordered proteins, whose chains are expanded, than on compact globular proteins. Classic theories of macromolecular crowding predict that increasing excluded volume effects will lead disordered proteins to compaction, and a great deal of data, from both simulation and experiments support this idea. We used nuclear magnetic resonance, circular dichroism, and fluorescence spectroscopies to characterize the structure and fibrillation of α-synuclein, an intrinsically disordered protein implicated in Parkinson's disease, using Ficoll70, its monomer sucrose and bovine serum albumin as crowding agents. Surprisingly, volume exclusion induced by high concentrations of macromolecules may not be the main reason for the compaction of α-synuclein. Our results indicate that all aspects crowding must be considered to understand protein conformation under crowded conditions.


Assuntos
Soroalbumina Bovina/química , Bibliotecas de Moléculas Pequenas/química , Sacarose/química , alfa-Sinucleína/química , Animais , Bovinos , Dicroísmo Circular , Substâncias Macromoleculares/química , Espectroscopia de Ressonância Magnética , Conformação Proteica , Espectrometria de Fluorescência
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