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1.
J Arthroplasty ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830430

RESUMO

BACKGROUND: Effective self-management after total knee arthroplasty (TKA) not only improves patients' knee pain and physical function but also improves quality of life. However, there is no assessment tool that can be targeted to evaluate the self-management level of patients after TKA. This study aimed to develop and validate a scale to specifically assess the level of self-management in patients after TKA. METHODS: The study was conducted in 2 steps: (1) instrument development and (2) psychological tests (n = 428). For the instrument development portion, scale items were generated through a literature review and semi-structured interviews, then reviewed and revised by a panel of experts, and assessed for content validity and pilot testing. For the psychometric tests component, items were analyzed using corrected item-total scale correlations, the critical ratio method, and Cronbach's α. Construct validity was evaluated using exploratory factor analysis and validation factor analysis. Criterion correlation validity was checked by calculating Pearson's correlation coefficient using the Arthritis Self-Efficacy Scale-8 and the scale developed in this study. Internal consistency reliability was evaluated using Cronbach's α and fold-half reliability, and retest reliability was assessed using intragroup correlation coefficients. RESULTS: The Patient Self-Management Scale after Total Knee Arthroplasty (PSMS-TKA) comprises 4 factors and 23 items that assess daily behavior management, disease information management, psychosocial management, and exercise rehabilitation management. Exploratory factor analysis and validation factor analysis yielded a stable 4-factor model for the 23 items. The PSMS-TKA demonstrated good criterion-related validity when using the Arthritis Self-Efficacy-8 as a criterion. The Cronbach's α of the PSMS-TKA was 0.903, the split-half reliability was 0.934, and the test-retest reliability correlation coefficient was 0.887 (P < .01); thus, the reliability of the scale is good. CONCLUSIONS: The PSMS-TKA developed in this study has good validity and reliability and can be used to assess the level of self-management in patients after TKA. The scale helps healthcare professionals understand the level of self-management of patients undergoing TKA.

2.
Int J Mol Sci ; 25(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474217

RESUMO

Nitrogen is a crucial element that impacts rice yields, and effective tillering is a significant agronomic characteristic that can influence rice yields. The way that reduced nitrogen affects effective tillering is a complex quantitative trait that is controlled by multiple genes, and its genetic basis requires further exploration. In this study, 469 germplasm varieties were used for a genome-wide association analysis aiming to detect quantitative trait loci (QTL) associated with effective tillering at low (60 kg/hm2) and high (180 kg/hm2) nitrogen levels. QTLs detected over multiple years or under different treatments were scrutinized in this study, and candidate genes were identified through haplotype analysis and spatio-temporal expression patterns. A total of seven genes (NAL1, OsCKX9, Os01g0690800, Os02g0550300, Os02g0550700, Os04g0615700, and Os04g06163000) were pinpointed in these QTL regions, and were considered the most likely candidate genes. These results provide favorable information for the use of auxiliary marker selection in controlling effective tillering in rice for improved yields.


Assuntos
Estudo de Associação Genômica Ampla , Oryza , Mapeamento Cromossômico , Oryza/genética , Nitrogênio , Locos de Características Quantitativas
3.
J Environ Manage ; 364: 121388, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38875980

RESUMO

Resource-based cities (RBCs) worldwide with a single industrial structure face the double pressures of sustainable development to promote development (i.e., industrial upgrading) and mitigating carbon emissions. Although building extraregional linkages is a potential path to advance this goal, the action of these linkages still requires study since there are many contradictory conclusions in the literature. To fill this gap, the study addresses the relationship between extraregional linkages, industrial upgrading, and the low-carbon transition in RBCs from 2012 to 2019 with the help of econometric panel models with proposed variables (e.g., the coupling coordination degree of extraregional technology and investment, CCD) built from multiple new data sources. The results are as follows. First, the diversification and specialization of the local industrial structure in RBCs both reduce carbon efficiency (CE). Second, extraregional technology, on its own, does not directly enhance CE as investments do. Third, the CCD not only serves to augment CE but also acts as a mitigating factor against CE reduction during industrial diversification. Based on the above findings, distinct low-carbon transition pathways are suggested for various types of RBCs, considering their positions within the extraregional linkage network.


Assuntos
Carbono , Cidades , Desenvolvimento Sustentável , Investimentos em Saúde , Tecnologia
4.
Heart Fail Rev ; 28(4): 905-923, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36184714

RESUMO

Several guidelines have recommended the use of angiotensin receptor neprilysin inhibitors (ARNIs) as replacement for angiotensin-converting enzyme inhibitors in the management of heart failure. Till date, there are no reviews done that comprehensively cover different aspects of efficacy and safety parameters. Hence, we have performed a comprehensive systematic review and meta-analysis on role of ARNIs for the management of heart failure patients. Searches were done in Embase, Scopus, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, PubMed Central, Cochrane Library, MEDLINE, Google Scholar, ScienceDirect and Clinicaltrials.gov until June 2022. Risk of bias assessment was done with Cochrane's risk of bias tool. Meta-analysis was carried out using random-effects model. Pooled standardized mean difference (SMD)/mean difference (MD) and/or risk ratio (RR) with 95% confidence intervals (CIs) was reported. In total, we analysed 34 studies, with almost all of them had a high risk of bias. Pooled RR was 0.88 (95% CI: 0.82-0.95) for all-cause mortality, 0.84 (95% CI: 0.77-0.92) for cardiovascular mortality and 0.78 (95% CI: 0.70-0.87) for hospitalization. Pooled MD was 3.74 (95% CI: 1.93-5.55) for left ventricular ejection fraction, -2.16 (95% CI: -3.58 to -0.74) for left atrial volume index, -3.80 (95% CI: -6.60 to -1.00) for left ventricular end-diastolic dimension and -1.16 (95% CI: -1.98 to -0.35) for E/E' ratio. Regarding adverse events, pooled RR was 1.55 (95% CI: 1.31-1.85) for symptomatic hypotension, 0.93 (95% CI: 0.78-1.11) for worsening renal function, 1.09 (95% CI: 0.94-1.26) for hyperkalaemia and 1.29 (95% CI: 0.67-2.50) for angioedema. ARNIs had beneficial efficacy and safety profile on the management of heart failure especially patients with reduced ejection fraction.


Assuntos
Insuficiência Cardíaca , Neprilisina , Humanos , Volume Sistólico , Função Ventricular Esquerda , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Cardíaca/tratamento farmacológico , Antagonistas de Receptores de Angiotensina/efeitos adversos
5.
Am J Emerg Med ; 65: 130-138, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36630861

RESUMO

OBJECTIVES: Airway management during cardiopulmonary resuscitation is particularly important for patients with out-of-hospital cardiac arrest (OHCA). This study was performed to compare the efficacy of the most commonly used out-of-hospital airway management methods in increasing the survival to discharge in patients with OHCA. METHODS: We screened all relevant literature from database inception to 21st January 2019 in PubMed, Web of Science, Embase, and the Cochrane Library. We included all randomized controlled trials (RCTs) of airway management for OHCA in adults (≥16 years of age) with no limitations on publication status, publication date, or language. The primary outcome was survival to discharge. The secondary outcomes were the overall airway technique success rate, return of spontaneous circulation, and survival to hospital admission. RESULTS: Overall, from 1986 to 2018, 9 RCTs involving 13,949 patients were included in the network meta-analysis, and the efficacy of six airway management methods for patients with OHCA were compared. However, none of the results were statistically significant. CONCLUSIONS: As the gold standard of airway management for patients with out-of-hospital cardiac arrest in most countries, endotracheal intubation (ETI) has been widely used for many years. However, our systematic review and network meta-analysis showed that ETI is no better than other methods in increasing the survival to discharge. This is not directly proportional to the various preparations required before ETI. Additional randomized controlled trials are needed to identify more effective methods and improve patients' outcome.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Metanálise em Rede , Manuseio das Vias Aéreas/métodos , Intubação Intratraqueal/métodos , Reanimação Cardiopulmonar/métodos , Serviços Médicos de Emergência/métodos
6.
J Strength Cond Res ; 37(1): 114-122, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34711769

RESUMO

ABSTRACT: Niu, X, Han, P, Tang, Z, Huang, J, Li, L, He, H, Zhang, W, Zhao, L, and Zhao, L. Cold stress induced a higher level of fat oxidation in women. J Strength Cond Res 37(1): 114-122, 2023-To investigate women's fat oxidation under cold stress during incremental exercise testing and compare the effect of cold stress on fat oxidation between the sexes. Twenty-six healthy subjects performed 2 incremental exercise tests to determine maximal oxygen uptake (V̇ o2 max) on a treadmill in different ambient temperatures. Cardiopulmonary variables were continuously recorded during incremental exercise tests. Maximal fat oxidation (MFO) and the corresponding exercise intensity (Fat max ) were determined from the fat oxidation curve constructed by indirect calorimetry. Both men and women relied more on fat oxidation in cold environment ( p < 0.05). Compared with men, fat oxidation was significantly greater in women in the cold environment from 50 to 70% V̇ o2 max ( p < 0.05). There were no significant differences in the change of fat oxidation as exercise intensity increased between the sexes ( p > 0.05). Women had a greater MFO ( p < 0.05) and Fat max ( p < 0.05) than men in the cold environment. When MFO was the dependent variable, sex, fat-free mass, fat mass, V̇ o2 max, and temperature accounted for 48% of its variability. We conclude that cold stress enhances fat oxidation in women. Compared with men, women have significantly higher value and rely more on fat oxidation to supply energy in the cold environment, although the increasing level of fat oxidation was similar between the sexes. These factors may have important implications in the individualization of exercise prescription in cold conditions for both men and women.


Assuntos
Exercício Físico , Consumo de Oxigênio , Masculino , Humanos , Feminino , Resposta ao Choque Frio , Calorimetria Indireta , Teste de Esforço , Oxirredução , Tecido Adiposo/metabolismo
7.
BMC Cardiovasc Disord ; 22(1): 553, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536277

RESUMO

BACKGROUND: Cardiac myxofibrosarcoma is a rare cardiac malignant tumor, whose diagnosis is challenging due to its rare and non-specific manifestations. Ultrasound is the most important tool for detecting cardiac tumors. Yet, its diagnostic value in cardiac myxoidfibrosarcoma is rarely reported. Herein, we summarized the ultrasonic manifestations of myxofibrosarcoma in a 72-year-old Han woman. CASE PRESENTATION: The patient presented with crushing chest pain without obvious inducement, lasting 3-5 min each time, which would be relieved after rest, accompanied by palpitation, chest tightness, shortness of breath, dizziness, and syncope. The electrocardiogram (ECG) suggested atrial fibrillation. Ultrasound found two moderate echogenic masses in the left atrium; one was about 48 × 31 mm in size, and the other was about 25 × 24 mm in size. The clinical diagnosis was atrial mass and atrial fibrillation. The patient underwent the operation of left atrial tumor resection + mitral valvuloplasty + atrial fibrillation radiofrequency ablation + left atrial appendectomy. The tumor was completely removed, and the patient did not receive radiotherapy or chemotherapy after surgery. The patient was reexamined by ultrasound at 6, 42, and 91 days after surgery, and no obvious abnormalities were found. On day 115, moderate echoic mass was detected on the posterior wall of the left atrium, nearing the mitral valve ring, with a size of about 28 × 23 mm. Currently, the patient is under follow-up care. CONCLUSION: As the most important examination method for cardiac tumors, cardiac ultrasound has good diagnostic and differential diagnosis value and can be used regularly due to its simplicity and safety. The diagnosis rate of cardiac myxofibrosarcoma can be greatly improved by summarizing the ultrasonographic manifestations of cardiac myxofibrosarcoma and differentiating them from other lesions.


Assuntos
Fibrilação Atrial , Procedimentos Cirúrgicos Cardíacos , Neoplasias Cardíacas , Feminino , Humanos , Adulto , Idoso , Átrios do Coração , Ultrassonografia , Valva Mitral/diagnóstico por imagem , Neoplasias Cardíacas/cirurgia
8.
Curr Psychol ; : 1-15, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36573180

RESUMO

Recent developments in the field of second language acquisition have led to a growing interest in exploring the influential power of domain-general psychological properties in the L2 learning context. Several attempts have been made to elucidate the impact of properties such as boredom, resilience and enjoyment, etc. However, the association between psychopathology and second language learning psychology has received scant attention and has not been closely examined. Hence, the current study aims to explore the impact of mental disturbance on second language learning psychology and delineate the influential trajectory, by referring to the network approach as the theoretical foundation. Participants were 173 Chinese speakers of L2 English. By performing correlation analysis and structural equation modelling analysis, this research revealed that mental disturbance had a significant positive impact on L2 anxiety and a significant negative impact on L2 autonomy and L2 self-efficacy. L2 anxiety and L2 autonomy acted as mediating roles in the impact of mental disturbance on L2 self-efficacy, in which a chain mediation trajectory was detected. An expanded network approach was thus advanced. Pedagogical implication and future research were identified and discussed.

9.
Small ; 17(18): e2007705, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33738957

RESUMO

Metastatic melanoma can be difficult to detect until at the advanced state that decreases the survival rate of patients. Several FDA-approved BRAF inhibitors have been used for treatment of metastatic melanoma, but overall therapeutic efficacy has been limited. Lutetium-177 (177 Lu) enables simultaneous tracking of tracer accumulation with single-photon emission computed tomography and radiotherapy. Therefore, the codelivery of 177 Lu alongside chemotherapeutic agents using nanoparticles (NPs) might improve the therapeutic outcome in metastatic melanoma. Cellulose nanocrystals (CNC NPs) can particularly deliver payloads to lung capillaries in vivo. Herein, 177 Lu-labeled CNC NPs loaded with vemurafenib ([177 Lu]Lu-CNC-V NPs) is developed and the therapeutic effect in BRAF V600E mutation-harboring YUMM1.G1 murine model of lung metastatic melanoma is investigated. The [177 Lu]Lu-CNC-V NPs demonstrate favorable radiolabel stability, drug release profile, cellular uptake, and cell growth inhibition in vitro. In vivo biodistribution reveals significant retention of the [177 Lu]Lu-CNC-V NPs in the lung, liver, and spleen. Ultimately, the median survival time of animals is doubly increased after treatment with [177 Lu]Lu-CNC-V NPs compared to control groups. The enhanced therapeutic efficacy of [177 Lu]Lu-CNC-V NPs in the lung metastatic melanoma animal model provides convincing evidence for the potential of clinical translation for theranostic CNC NP-based drug delivery systems after intravenous administration.


Assuntos
Melanoma , Nanopartículas , Animais , Linhagem Celular Tumoral , Celulose , Sistemas de Liberação de Medicamentos , Humanos , Melanoma/tratamento farmacológico , Camundongos , Medicina de Precisão , Distribuição Tecidual
10.
Toxicol Appl Pharmacol ; 409: 115271, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33065153

RESUMO

With the growth of the aging population, osteoporosis is becoming a global health problem. Ursolic acid (UA) is an active ingredient existed in a variety of foods and nature plants and owns plenty of pharmacological effects especially in treating metabolic disease. Our predication from network pharmacology hinted that UA has potential for ameliorating osteoporosis. Firstly through in vivo experiment, we confirmed that UA administration obviously protected against ovariectomy (OVX)-induced osteoporosis in rats by improving microarchitectural deterioration of trabecular bone (P < 0.001), decreasing numbers of TRAP positive osteoclast in vertebra (P < 0.001), as well as decreasing serum osteoclast-specific cytokines release (P < 0.001). Besides, UA ameliorated kidney damage secondary to OVX-induced osteoporosis by ameliorating glomerular atrophy, decreasing BUN and creatinine levels in OVX rats. In vitro, UA noticeably decreased osteoclastic-special marker proteins c-Fos and NFATc1 expressions (P < 0.001) in response to RANKL stimulation in macrophagy. Importantly, autophagy pathway was activated in the process of osteoclast differentiation and blocked by UA pretreatment. Furthermore, autophagy inhibitors suppressed osteoclast differentiation (P < 0.001). Collectively, UA may ameliorate osteoporosis by suppressing osteoclast differentiation mediated by autophagy. Our research provides scientific support for UA treating osteoporosis and offers an optimal dose for daily intake of UA safely to prevent bone diseases.


Assuntos
Autofagia/efeitos dos fármacos , Produtos Biológicos/farmacologia , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Triterpenos/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Feminino , Camundongos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Ovariectomia/métodos , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Ácido Ursólico
11.
Int J Neuropsychopharmacol ; 23(4): 207-216, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31967315

RESUMO

OBJECTIVE: Electroconvulsive therapy (ECT) is an effective option for treatment-resistant bipolar disorder (trBD). However, the mechanisms of its effect are unknown. Oxidative stress is thought to be involved in the underpinnings of BD. Our study is the first, to our knowledge, to report the association between notable oxidative stress parameters (superoxide dismutase [SOD], glutathione peroxidase [GSH-Px], catalase [CAT], and malondialdehyde [MDA]) levels and ECT response in trBD patients. METHODS: A total 28 trBD patients and 49 controls were recruited. Six-week ECT and naturalistic follow-up were conducted. SOD, GSH-Px, CAT, and MDA levels were measured by enzyme-linked immunosorbent assay, and the 17-item Hamilton Depression Rating Scale and Young Mania Rating Scale were administered at baseline and the end of the 6th week. MANCOVA, ANCOVA, 2 × 2 ANCOVA, and a multiple regression model were conducted. RESULTS: SOD levels were lower in both trBD mania and depression (P = .001; P = .001), while GSH-Px (P = .01; P = .001) and MDA (P = .001; P = .001) were higher in both trBD mania and depression compared with controls. CAT levels were positively associated with 17-item Hamilton Depression Rating Scale scores in trBD depression (radjusted = 0.83, P = .005). MDA levels in trBD decreased after 6 weeks of ECT (P = .001). Interestingly, MDA levels decreased in responders (P = .001) but not in nonresponders (P > .05). CONCLUSIONS: Our study indicates that decreased SOD could be a trait rather than a state in trBD. Oxidative stress levels are associated with illness severity and ECT response. This suggests that the mechanism of oxidative stress plays a crucial role in the pathophysiology of trBD.


Assuntos
Transtorno Bipolar/metabolismo , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/terapia , Eletroconvulsoterapia , Avaliação de Resultados em Cuidados de Saúde , Estresse Oxidativo/fisiologia , Superóxido Dismutase/sangue , Adulto , Catalase/sangue , Feminino , Seguimentos , Glutationa Peroxidase/sangue , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Adulto Jovem
12.
Mol Cell Biochem ; 472(1-2): 241-251, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32632611

RESUMO

BACKGROUND AND AIM: Secreted frizzled-related protein 2 (sFRP2) has been reported to be involved in cardiovascular diseases. However, its role in cardiac hypertrophy induced by pressure overload is still elusive. We aimed to examine the role of sFRP2 in the development of cardiac hypertrophy in vivo and in vitro. METHODS AND RESULTS: Following cardiac hypertrophy stimulated by aortic banding (AB), the expression of sFRP2 was downregulated in the hypertrophic ventricle. Adeno-associated virus 9 (AAV9) was injected through the tail vein to overexpress sFRP2 in the mouse myocardium. Overexpression of sFRP2 alleviated cardiomyocyte hypertrophy and interstitial fibrosis, as identified by the reduced cardiomyocyte cross-sectional area, heart weight/body weight ratio, and left ventricular (LV) collagen ratio. Additionally, sFRP2 decreased cardiomyocyte apoptosis induced by pressure overload. Western blot showed that sFRP2 prevented the expression of active ß-catenin. The Wnt/ß-catenin agonist LiCl (1 mmol/kg) abolished the inhibitory effects of sFRP2 on cardiac hypertrophy and apoptosis, as evidenced by the increased cross-sectional area and LV collagen ratio and the deterioration of echocardiographic data. CONCLUSION: Our study indicated that decreased sFRP2 levels were observed in failing mouse hearts. Overexpression of sFRP2 attenuated myocyte hypertrophy and interstitial fibrosis induced by hypertrophic stimuli by inhibiting the Wnt/ß-catenin pathway. We revealed that sFRP2 may be a promising therapeutic target for the development of cardiac remodeling.


Assuntos
Cardiomegalia/prevenção & controle , Proteínas de Membrana/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Animais Recém-Nascidos , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Modelos Animais de Doenças , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Pressão , Ratos , Ratos Sprague-Dawley , Proteínas Wnt/genética , beta Catenina/genética
13.
J Environ Manage ; 264: 110442, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250887

RESUMO

Eco-efficiency can effectively measure the relationship between economy, resources, environment, and development. Understanding eco-efficiency is of great practical significance for decision makers tasked with addressing and delivering sustainable socioeconomic development. Based on an "undesirable output Slacks-Based Measure models," this study evaluated the eco-efficiency of 285 Chinese cities during the period 2004-2014, analyzing spatiotemporal dynamics and influencing factors using a Spatial Autocorrelation Panel Data Model. The main results are as follows: From the spatial perspective, eco-efficiency in Chinese cities generally evidenced an M-shaped trend (increasing-decreasing-increasing-decreasing), and imbalanced spatiotemporal dynamics. Furthermore, the urban eco-efficiency generally presented a distinct convergence of HH cluster and LL cluster clubs, with the latter being the most dominant. From the regional point of view, there existed a decreasing trend in the efficiencies of cities, from eastern China to central and western China. In addition, we identified significant differences in the eco-efficiency of different cities in China, and the coefficient of variation of eco-efficiency showed a general decrease. The results of our estimation of the factors affecting urban eco-efficiency showed that the economic development level, the industrial structure, import and export trade, and the information level all had significant positive influence, and local government expenditure, social retail sales of consumer goods, and infrastructure all had a negative effect on urban eco-efficiency. This paper puts forward numbers of suggestions for ways to promote social, ecological, and economic development in Chinese cities, based on our findings.


Assuntos
Desenvolvimento Econômico , Eficiência , China , Cidades , Análise Espaço-Temporal
14.
Mikrochim Acta ; 186(7): 412, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187285

RESUMO

Mesoporous silica-coated solid phase microextraction (SPME) Arrow systems were developed for capturing of low-molecular-weight aliphatic amines (LMWAAs) from complicated sample matrices. Specifically, silicas of type MCM-41, SBA-15 and KIT-6 were chosen as substrates to afford size-exclusion selectivity. They possess ordered multidimensional pore-channel structures and mesopore sizes between 3.8 and 8.2 nm. Their surface acidity was enhanced by grafting them with a layer of titanium hydrogenphosphate (-TP). This enhanced the chemical selectivity for basic LMWAAs. The siliceous coatings increased the extraction of ethylamine, diethylamine (DEA) and triethylamine (TEA) by factors of 18.6-102.5, 4.8-10.8 and 2.6-4.0, respectively, when compared to the commercial SPME Arrow with polydimethylsiloxane/divinylbenzene coating. Among them, the MCM-41 and MCM-41-TP coated SPME Arrows demonstrated exceptional selectivity towards LMWAAs that were quantified by gas chromatography-mass spectrometry (GC-MS). The total peak area ratios of LMWAAs/ten competing compounds were 25.4 and 36.3, respectively. The extraction equilibrium was reached within 20-30 min. The MCM-41 and MCM-41-TP derived SPME Arrows gave very similar results (18.4 ± 2.1-376 ± 12 ng g-1 to DEA and TEA) when applied to urban mushroom samples. SPME Arrow with MCM-41 coatings followed by GC-MS was applied also to the analysis of atmospheric air and urine samples resulting in high selectivity due to the size and mesoporous structure of the functionalized silica, and its chemical interactions with the LMWAAs. Graphical abstract Scheme of synthesis of the MCM-41 silicas, and the preparation of solid phase microextraction Arrow coatings. They were employed for selective capturing of aliphatic amines from complex sample matrices, followed by gas chromatography-mass spectrometry.

15.
Int J Mol Sci ; 20(23)2019 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-31771277

RESUMO

Nitrogen is an essential nutrient for plant growth and basic metabolic processes. Root systems play an important role in the ability of plants to obtain nutrients from the soil, and are closely related to the growth and development of above-ground plants. Root morphology analysis showed that root growth was induced under low-nitrogen conditions and inhibited under high-nitrogen conditions. To better understand the molecular mechanisms and metabolic basis underlying the rice root response to nitrogen availability, an integrated analysis of the rice root transcriptome and metabolome under three environmental conditions (low-, control, and high-nitrogen conditions) was conducted. A total of 262 and 262 differentially level metabolites were identified under low- and high-nitrogen conditions, respectively. A total of 696 and 808 differentially expressed genes were identified under low- and high-nitrogen conditions, respectively. For both the differentially expressed genes and metabolites, KEGG pathway analysis indicated that amino acid metabolism, carbon and nitrogen metabolism, phenylpropanoid metabolism, and phytohormones' signal transduction were significantly affected by nitrogen availability. Additionally, variable levels of 65 transcription factors (TFs) were identified in rice leaves exposed to high and low nitrogen, covering 22 TF families. These results also indicate that there is a significant difference in the transcriptional regulation mechanisms of rice roots between low and high nitrogen. In summary, our study provides new information for a further understanding of the response of rice roots to low-nitrogen and high-nitrogen conditions.


Assuntos
Metaboloma , Nitrogênio/metabolismo , Oryza/metabolismo , Transcriptoma , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Propanóis/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Fatores de Transcrição/metabolismo
16.
Int J Mol Sci ; 20(9)2019 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-31083591

RESUMO

Nitrogen (N) is an extremely important macronutrient for plant growth and development. It is the main limiting factor in most agricultural production. However, it is well known that the nitrogen use efficiency (NUE) of rice gradually decreases with the increase of the nitrogen application rate. In order to clarify the underlying metabolic and molecular mechanisms of this phenomenon, we performed an integrated analysis of the rice transcriptome and metabolome. Both differentially expressed genes (DEGs) and metabolite Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that carbon and nitrogen metabolism is significantly affected by nitrogen availability. Further analysis of carbon and nitrogen metabolism changes in rice under different nitrogen availability showed that high N inhibits nitrogen assimilation and aromatic metabolism pathways by regulating carbon metabolism pathways such as the tricarboxylic acid (TCA) cycle and the pentose phosphate pathway (PPP). Under low nitrogen, the TCA cycle is promoted to produce more energy and α-ketoglutarate, thereby enhancing nitrogen transport and assimilation. PPP is also inhibited by low N, which may be consistent with the lower NADPH demand under low nitrogen. Additionally, we performed a co-expression network analysis of genes and metabolites related to carbon and nitrogen metabolism. In total, 15 genes were identified as hub genes. In summary, this study reveals the influence of nitrogen levels on the regulation mechanisms for carbon and nitrogen metabolism in rice and provides new insights into coordinating carbon and nitrogen metabolism and improving nitrogen use efficiency in rice.


Assuntos
Carbono/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metaboloma/genética , Nitrogênio/metabolismo , Oryza/genética , Aminoácidos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Metabolômica , Nitrogênio/farmacologia , Oryza/efeitos dos fármacos , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Fatores de Transcrição/metabolismo
17.
J Cell Mol Med ; 22(11): 5565-5572, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30134003

RESUMO

Long non-coding RNAs (lncRNAs) have emerged as important regulators of cancer, including colorectal cancer (CRC). The exact expression pattern of long intergenic noncoding RNA 00312 (LINC00312) in CRC and its mechanisms of action have not been reported. Here, we found that LINC00312 is underexpressed in CRC tissues and cell lines. Functional experiments suggested that LINC00312 suppresses growth, migration and invasion of CRC cells in vitro and attenuates tumour proliferation and metastasis in vivo. Mechanistically, LINC00312 was found to regulate the malignancy of CRC cells by binding to miR-21 and by functioning as a tumour suppressor targeting PTEN. Overexpression of miR-21 or knockdown of PTEN attenuated the LINC00312-mediated inhibition of CRC cell proliferation and invasion. Taken together, our results elucidate the role of the LINC00312-miR-21-PTEN axis in CRC cell proliferation and tumour progression and may lead to new lncRNA-based diagnostics or therapeutics for CRC.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/genética , Animais , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Células HT29 , Xenoenxertos , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica
18.
Chirality ; 30(4): 498-508, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29359493

RESUMO

Herein we present design, synthesis, chiral HPLC resolution, and kinetics of racemization of axially chiral Ni(II) complexes of glycine and di-(benzyl)glycine Schiff bases. We found that while the ortho-fluoro derivatives are configurationally unstable, the pure enantiomers of corresponding axially chiral ortho-chloro-containing complexes can be isolated by preparative HPLC and show exceptional configurational stability (t1/2 from 4 to 216 centuries) at ambient conditions. Synthetic implications of this discovery for the development of new generation of axially chiral auxiliaries, useful for general asymmetric synthesis of α-amino acids, are discussed.


Assuntos
Aminoácidos/química , Níquel/química , Aminoácidos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Flúor/química , Glicina/química , Bases de Schiff/química , Estereoisomerismo
19.
Chemistry ; 23(47): 11221-11225, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28639718

RESUMO

This work describes, for the first time, Michael addition reactions of tertiary fluoro-enolates in situ generated by detrifluoroacetylation with 1-(1-(phenylsulfonyl) vinylsulfonyl)benzene. Excellent enantioselectivity and chemical yields were achieved with application of catalysts (10 mol %) derived from Cu(OTf)2 and (1S,2S)-1,2-diphenylethane-1,2-diamine. These reactions show a considerable degree of structural generality and allow the preparation of new types of biologically relevant molecules that contain quaternary C-F stereogenic carbon atoms and feature five-, six-, or seven-membered rings as well as heterocyclic 3-fluoro-2,3-dihydrochromen-4-one moieties.

20.
J Org Chem ; 82(18): 9824-9831, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28845667

RESUMO

A cascade visible-light photocatalytic difluoroalkylation and intramolecular cyclization reaction has been developed for the synthesis of difluoroalkylated oxygen heterocycles. The reaction was carried out under very mild conditions, affording fluorinated isobenzofuran-1-ones, lactone, and cyclic ethers with up to 97% chemical yields. Furthermore, several types of bromofluoroalkane precursors bearing ester, keto, amido, and phosphate groups could all work very well in this reaction, which provides an easy method for the preparation of functionalized difluoroalkylated oxygen heterocycles.

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