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1.
Thorax ; 79(7): 615-623, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38388490

RESUMO

BACKGROUND: There is growing interest in the joint effects of hazardous trace elements (HTEs) on lung function deficits, but the data are limited. This is a critical research gap given increased global industrialisation. METHODS: A national cross-sectional study including spirometry was performed among 2112 adults across 11 provinces in China between 2020 and 2021. A total of 27 HTEs were quantified from urine samples. Generalised linear models and quantile-based g-computation were used to explore the individual and joint effects of urinary HTEs on lung function, respectively. RESULTS: Overall, there were negative associations between forced expiratory volume in 1 s (FEV1) and urinary arsenic (As) (z-score coefficient, -0.150; 95% CI, -0.262 to -0.038 per 1 ln-unit increase), barium (Ba) (-0.148, 95% CI: -0.258 to -0.039), cadmium (Cd) (-0.132, 95% CI: -0.236 to -0.028), thallium (Tl) (-0.137, 95% CI: -0.257 to -0.018), strontium (Sr) (-0.147, 95% CI: -0.273 to -0.022) and lead (Pb) (-0.121, 95% CI: -0.219 to -0.023). Similar results were observed for forced vital capacity (FVC) with urinary As, Ba and Pb and FEV1/FVC with titanium (Ti), As, Sr, Cd, Tl and Pb. We found borderline associations between the ln-quartile of joint HTEs and decreased FEV1 (-20 mL, 95% CI: -48 to +8) and FVC (-14 mL, 95% CI: -49 to+2). Ba and Ti were assigned the largest negative weights for FEV1 and FVC within the model, respectively. CONCLUSION: Our study investigating a wide range of HTEs in a highly polluted setting suggests that higher urinary HTE concentrations are associated with lower lung function, especially for emerging Ti and Ba, which need to be monitored or regulated to improve lung health.


Assuntos
Exposição Ambiental , Oligoelementos , Humanos , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , China/epidemiologia , Oligoelementos/urina , Adulto , Volume Expiratório Forçado , Espirometria , Capacidade Vital , Pulmão/fisiopatologia , Idoso
2.
Small ; 20(2): e2305639, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37658504

RESUMO

Prelithiation is an essential technology to compensate for the initial lithium loss of lithium-ion batteries due to the formation of solid electrolyte interphase (SEI) and irreversible structure change. However, the prelithiated materials/electrodes become more reactive with air and electrolyte resulting in unwanted side reactions and contaminations, which makes it difficult for the practical application of prelithiation technology. To address this problem, herein, interphase engineering through a simple solution treatment after chemical prelithiation is proposed to protect the prelithiated electrode. The used solutions are carefully selected, and the composition and nanostructure of the as-formed artificial SEIs are revealed by cryogenic electron microscopy and X-ray photoelectron spectroscopy. The electrochemical evaluation demonstrates the unique merits of this artificial SEI, especially for the fluorinated interphase, which not only enhances the interfacial ion transport but also increases the tolerance of the prelithiated electrode to the air. The treated graphite electrode shows an initial Coulombic efficiency of 129.4%, a high capacity of 170 mAh g-1 at 3 C, and negligible capacity decay after 200 cycles at 1 C. These findings not only provide a facile, universal, and controllable method to construct an artificial SEI but also enlighten the upgrade of battery fabrication and the alternative use of advanced electrolytes.

3.
Small ; 20(42): e2400498, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38863125

RESUMO

Sodium-ion battery (SIB) is a candidate for the stationary energy storage systems because of the low cost and high abundance of sodium. However, the energy density and lifespan of SIBs suffer severely from the irreversible consumption of the Na-ions for the formation of the solid electrolyte interphase (SEI) layer and other side reactions on the electrodes. Here, Na3.5C6O6 is proposed as an air-stable high-efficiency sacrificial additive in the cathode to compensate for the lost sodium. It is characteristic of low desodiation (oxidation) potential (3.4-3.6 V vs. Na+/Na) and high irreversible desodiation capacity (theoretically 378 mAh g-1). The feasibility of using Na3.5C6O6 as a sodium compensation additive is verified with the improved electrochemical performances of a Na2/3Ni1/3Mn1/3Ti1/3O2ǀǀhard carbon cells and cells using other cathode materials. In addition, the structure of Na3.5C6O6 and its desodiation path are also clarified on the basis of comprehensive physical characterizations and the density functional theory (DFT) calculations. This additive decomposes completely to supply abundant Na ions during the initial charge without leaving any electrochemically inert species in the cathode. Its decomposition product C6O6 enters the carbonate electrolyte without bringing any detectable negative effects. These findings open a new avenue for elevating the energy density and/or prolonging the lifetime of the high-energy-density secondary batteries.

4.
New Phytol ; 244(2): 511-527, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39060950

RESUMO

The ALMT1 transporter aids malate secretion, chelating Al3+ ions to form nontoxic Al-malate complexes, believed to exclude Al from the roots. However, the extent to which malate secreted by ALMT1 is solely used for the exclusion of Al3+ or can be reutilized by plant roots for internal Al tolerance remains uncertain. In our investigation, we explored the impact of malate secretion on both external and internal Al resistance in Arabidopsis thaliana. Additionally, we delved into the mechanism by which the tonoplast-localized bacterial-type ATP-binding cassette (ABC) transporter complex STAR1/ALS3 promotes the degradation of the Al resistance transcription factor STOP1 to regulate ALMT1 expression. Our study demonstrates that the level of secreted malate influences whether the Al-malate complex is excluded from the roots or transported into root cells. The nodulin 26-like intrinsic protein (NIP) subfamily members NIP1;1 and NIP1;2, located in the plasma membrane, coordinate with STAR1/ALS3 to facilitate Al-malate transport from root apoplasm to the symplasm and eventually to the vacuoles for the internal Al detoxification. ALS3-dependent STAR1 interacts with and promotes the degradation of STOP1, regulating malate exudation. Our findings demonstrate the dual roles of malate exudation in external Al exclusion and Al absorption for internal Al detoxification.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Alumínio , Proteínas de Arabidopsis , Arabidopsis , Malatos , Raízes de Plantas , Alumínio/toxicidade , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Malatos/metabolismo , Raízes de Plantas/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Transporte Biológico/efeitos dos fármacos , Transportadores de Ânions Orgânicos
5.
Eur J Clin Pharmacol ; 80(9): 1295-1304, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38801422

RESUMO

PURPOSE: To assess the pharmacokinetics and pharmacodynamics of linezolid in a retrospective cohort of hospitalized Chinese older patients. METHODS: Patients > 60 years of age, who received intravenous linezolid (600 mg), were included. A population pharmacokinetics (PPK) model was established using nonlinear mixed-effects modeling. The predictive performance of the final model was assessed using goodness-of-fit plots, bootstrap analyses, and visual predictive checks. Monte Carlo simulations were used to evaluate the achievement of a pharmacodynamics target for the area under the serum concentration-time curve/minimum inhibitory concentration (AUC0-24/MIC). RESULTS: A total of 210 samples were collected from 120 patients. A one-compartment PPK model with linear elimination best predicted the linezolid plasma concentrations. Linezolid clearance (CL) was 4.22 L h-1 and volume of distribution (Vd) was 45.80 L; serum uric acid (SUA) was a significant covariate of CL. CONCLUSION: The results of this study indicated that the standard dose was associated with a risk of overexposure in older patients, particularly those with high SUA values; these patients would benefit from a lower dose (300 mg every 12 h).


Assuntos
Antibacterianos , Área Sob a Curva , Linezolida , Modelos Biológicos , Humanos , Linezolida/farmacocinética , Linezolida/administração & dosagem , Linezolida/sangue , Idoso , Feminino , Masculino , Estudos Retrospectivos , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Método de Monte Carlo , Testes de Sensibilidade Microbiana , Ácido Úrico/sangue , China , Relação Dose-Resposta a Droga , População do Leste Asiático
6.
Plant Cell ; 32(12): 3921-3938, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33087527

RESUMO

Aluminum (Al) is a primary constraint for crop production on acid soils, which make up more than 30% of the arable land in the world. Al resistance in Arabidopsis (Arabidopsis thaliana) is achieved by malate secretion mediated by the Al-ACTIVATED MALATE TRANSPORTER1 (AtALMT1) transporter. The C2H2-type transcription factor SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) is essential and required for Al resistance, where it acts by inducing the expression of Al-resistance genes, including AtALMT1 In this study, we report that STOP1 protein function is modified by SUMOylation. The SMALL UBIQUITIN-LIKE MODIFIER (SUMO) protease ESD4, but not other SUMO proteases, specifically interacts with and deSUMOylates STOP1. Mutation of ESD4 increases the level of STOP1 SUMOylation and the expression of the STOP1-regulated gene AtALMT1, which contributes to the increased Al resistance in esd4 The esd4 mutation does not influence STOP1 protein abundance but increases the association of STOP1 with the AtALMT1 promoter, which might explain the elevated expression of AtALMT1 in esd4 We demonstrate that STOP1 is mono-SUMOylated at K40, K212, or K395 sites, and blocking STOP1 SUMOylation reduces STOP1 stability and the expression of STOP1-regulated genes, leading to the reduced Al resistance. Our results thus reveal the involvement of SUMOylation in the regulation of STOP1 and Al resistance in Arabidopsis.


Assuntos
Alumínio/efeitos adversos , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Transportadores de Ânions Orgânicos/metabolismo , Sumoilação , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transportadores de Ânions Orgânicos/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética
7.
Plant J ; 106(2): 493-506, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33528836

RESUMO

The C2H2-type zinc finger transcription factor sensitive to proton rhizotoxicity 1 (STOP1) is crucial for aluminum (Al) resistance in Arabidopsis. The F-box protein Regulation of AtALMT1 Expression 1 (RAE1) was recently reported to regulate the stability of STOP1. There is a unique homolog of RAE1, RAH1 (RAE1 homolog 1), in Arabidopsis, but the biological function of RAH1 is still not known. In this study, we characterize the role of RAH1 and/or RAE1 in the regulation of Al resistance and plant growth. We demonstrate that RAH1 can directly interact with STOP1 and promote its ubiquitination and degradation. RAH1 is preferentially expressed in root caps and various vascular tissues, and its expression is induced by Al and controlled by STOP1. Mutation of RAH1 in rae1 but not the wild-type (WT) background increases the level of STOP1 protein, leading to increased expression of STOP1-regulated genes and enhanced Al resistance. Interestingly, the rah1rae1 double mutant shows reduced plant growth compared with the WT and single mutants under normal conditions, and introduction of stop1 mutation into the double mutant background can rescue its reduced plant growth phenotype. Our results thus reveal that RAH1 plays an unequally redundant role with RAE1 in the modulation of STOP1 stability and plant growth, and dynamic regulation of the STOP1 level is critical for the balance of Al resistance and normal plant growth.


Assuntos
Alumínio/toxicidade , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas F-Box/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Proteínas F-Box/fisiologia , Regulação da Expressão Gênica de Plantas , Complexo de Proteínas Formadoras de Poros Nucleares/fisiologia , Estresse Fisiológico , Fatores de Transcrição/fisiologia , Ubiquitinação
8.
BMC Genomics ; 23(1): 418, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35659179

RESUMO

BACKGROUND: Temperature is involved in the regulation of carotenoid accumulation in many plants. The floral color of sweet osmanthus (Osmanthus fragrans Lour.) which is mainly contributed by carotenoid content, is affected by temperature in autumn. However, the mechanism remains unknown. Here, to reveal how temperature regulates the floral color of sweet osmanthus, potted sweet osmanthus 'Jinqiu Gui' were treated by different temperatures (15 °C, 19 °C or 32 °C). The floral color, carotenoid content, and the expression level of carotenoid-related genes in petals of sweet osmanthus 'Jinqiu Gui' under different temperature treatments were investigated. RESULTS: Compared to the control (19 °C), high temperature (32 °C) changed the floral color from yellow to yellowish-white with higher lightness (L*) value and lower redness (a*) value, while low temperature (15 °C) turned the floral color from yellow to pale orange with decreased L* value and increased a* value. Total carotenoid content and the content of individual carotenoids (α-carotene, ß-carotene, α-cryptoxanthin, ß-cryptoxanthin, lutein and zeaxanthin) were inhibited by high temperature, but were enhanced by low temperature. Lower carotenoid accumulation under high temperature was probably attributed to transcriptional down-regulation of the biosynthesis gene OfPSY1, OfZ-ISO1 and OfLCYB1, and up-regulation of degradation genes OfNCED3, OfCCD1-1, OfCCD1-2, and OfCCD4-1. Up-regulation of OfLCYB1, and down-regulation of OfNCED3 and OfCCD4-1 were predicted to be involved in low-temperature-regulated carotenoid accumulation. Luciferase assays showed that the promoter activity of OfLCYB1 was activated by low temperature, and repressed by high temperature. However, the promoter activity of OfCCD4-1 was repressed by low temperature, and activated by high temperature. CONCLUSIONS: Our study revealed that high temperature suppressed the floral coloration by repressing the expression of carotenoid biosynthesis genes, and activating the expression of carotenoid degradation genes. However, the relative low temperature had opposite effects on floral coloration and carotenoid biosynthesis in sweet osmanthus. These results will help reveal the regulatory mechanism of temperature on carotenoid accumulation in the petals of sweet osmanthus.


Assuntos
Citrus sinensis , Oleaceae , Carotenoides/metabolismo , Citrus sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Oleaceae/genética , Oleaceae/metabolismo , Temperatura
9.
J Am Chem Soc ; 144(41): 19137-19149, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36206144

RESUMO

Solar cells and optoelectronic devices are exposed to heat that degrades performance. Therefore, elucidating temperature-dependent charge carrier dynamics is essential for device optimization. Charge carrier lifetimes decrease with temperature in conventional semiconductors. The opposite, anomalous trend is observed in some experiments performed with MAPbI3 (MA = CH3NH3+) and other metal halide perovskites. Using ab initio quantum dynamics simulation, we establish the atomic mechanisms responsible for nonradiative electron-hole recombination in orthorhombic-, tetragonal-, and cubic MAPbI3. We demonstrate that structural disorder arising from the phase transitions is as important as the disorder due to heating in the same phase. The carrier lifetimes grow both with increasing temperature in the same phase and upon transition to the higher-temperature phases. The increased lifetime is rationalized by structural disorder that induces partial charge localization, decreases nonadiabatic coupling, and shortens quantum coherence. Inelastic and elastic electron-vibrational interactions exhibit opposite dependence on temperature and phase. The partial disorder and localization arise from thermal motions of both the inorganic lattice and the organic cations and depend significantly on the phase. The structural deformations induced by thermal fluctuations and phase transitions are on the same order as deformations induced by defects, and hence, thermal disorder plays a very important role. Since charge localization increases carrier lifetimes but inhibits transport, an optimal regime maximizing carrier diffusion can be designed, depending on phase, temperature, material morphology, and device architecture. The atomistic mechanisms responsible for the enhanced carrier lifetimes at elevated temperatures provide guidelines for the design of improved solar energy and optoelectronic materials.

10.
J Virol ; 95(5)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33328304

RESUMO

HIV persists in cellular reservoirs despite effective combined antiretroviral therapy (cART) and there is viremia flare up upon therapy interruption. Opioids modulate the immune system and suppress antiviral gene responses, which significantly impact people living with HIV (PLWH). However, the effect of opioids on viral reservoir dynamics remain elusive. Herein, we developed a morphine dependent SIVmac251 infected Rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. RMs on a morphine (or saline control) regimen were infected with SIVmac251. The cART was initiated in approximately half the animals five weeks post-infection, and morphine/saline administration continued until the end of the study. Among the untreated RM, we did not find any difference in plasma/CSF or in cell-associated DNA/RNA viral load in anatomical tissues. On the other hand, within the cART suppressed macaques, there was a reduction in cell-associated DNA load, intact proviral DNA levels, and in inducible SIV reservoir in lymph nodes (LNs) of morphine administered RMs. In distinction to LNs, in the CNS, the size of latent SIV reservoirs was higher in the CD11b+ microglia/macrophages in morphine dependent RMs. These results suggest that in the proposed model, morphine plays a differential role in SIV reservoirs by reducing the CD4+ T-cell reservoir in lymphoid tissues, while increasing the microglia/reservoir size in CNS tissue. The findings from this pre-clinical model will serve as a tool for screening therapeutic strategies to reduce/eliminate HIV reservoirs in opioid dependent PLWH.IMPORTANCE Identification and clearance of HIV reservoirs is a major challenge in achieving a cure for HIV. This is further complicated by co-morbidities that may alter the size of the reservoirs. There is an overlap between the risk factors for HIV and opioid abuse. Opiates have been recognized as prominent co-morbidities in HIV-infected populations. People infected with HIV also abusing opioids have immune modulatory effects and more severe neurological disease. However, the impact of opioid abuse on HIV reservoirs remains unclear. In this study, we used morphine dependent SIVmac251 infected rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. Our studies suggested that people with HIV who abuse opioids had higher reservoirs in CNS than the lymphoid system. Extrapolating the macaque findings in humans suggests that such differential modulation of HIV reservoirs among people living with HIV abusing opioids could be considered for future HIV cure research efforts.

11.
Phys Chem Chem Phys ; 24(48): 29918-29926, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36468632

RESUMO

Photocyclization and photoisomerization of fulgides have been extensively studied experimentally and computationally due to their significant potential applications for example as photoswitches in memory devices. However, the reported excited-state decay mechanisms of fulgides do not include the effects of solvation explicitly to date. Herein, calculations using the high-level MS-CASPT2//CASSCF method were conducted to explore the photoinduced excited-state decay processes of the Eα conformer of a fulgide derivative in toluene with solvent effects treated by implicit PCM and explicit QM/MM models, respectively. Several minima and conical intersections were optimized successfully in and between the S0 and S1 states; then, two nonadiabatic excited-state decay channels that could efficiently drive the system to the ground state were proposed based on the excited-state ring-closure and isomerization paths. In addition, we also found that in the ring-closure path, the potential energy surface is essentially barrierless before approaching the conical intersection, while it needs to overcome a small energy barrier along the E → Z photoisomerization path for the nonadiabatic S1 → S0 internal conversion process. The present computational results could provide useful mechanistic insights into the photoinduced cyclization and isomerization reactions of fulgide and its derivatives.


Assuntos
Tolueno , Ciclização
12.
J Phys Chem A ; 126(26): 4176-4184, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35737507

RESUMO

Arylene diimide compounds exhibit thermally activated delayed fluorescence (TADF), but its mechanism remains elusive. Herein we studied the TADF mechanism of a carbazole-substituted pyromellitic diimide derivative (CzPhPmDI) in poly(methyl methacrylate) (PMMA) film by using DFT, TD-DFT, and MS-CASPT2 methods within the QM/MM framework. We found that the TADF mechanism involves three electronic states (i.e., S0, S1, and T1), but the T2 state is not involved because its energy is higher than the S1 state by 6.9 kcal/mol. By contrast, the T1 state is only 3.2 kcal/mol lower than the S1 state and such small energy difference benefits the reverse intersystem crossing (rISC) process from T1 to S1 thereto TADF. This point is seconded by relevant radiative and nonradiative rates calculated. At room temperature, the ISC rate from S1 to T1 is calculated to be 6.1 × 106 s-1, which is larger than the fluorescence emission rate, 2.2 × 105 s-1; thus, the dominant S1 population converts to the T1 state. However, in the T1 state, the rISC process (1.8 × 104 s-1) becomes the most important channel because of the negligible phosphorescence emission rate (3.5 × 10-2 s-1). So, the T1 population is still converted back to the S1 state to fluoresce enabling TADF. Unfortunately, the rISC process is blocked in low temperature. Besides, we found that relevant Huang-Rhys factors have dominant contribution from low-frequency vibrational motion related to the torsional motion of functional groups. These gained insights could provide useful information for the design of organic TADF materials with excellent luminescence efficiency.


Assuntos
Eletrônica , Imidoésteres , Teoria da Densidade Funcional , Fluorescência
13.
J Sep Sci ; 45(6): 1146-1152, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34981883

RESUMO

Regadenoson, the first selective adenosine A2A receptor agonist, is used to perform exercise stress test during radionuclide myocardial perfusion imaging. To detect the concentration of regadenoson in human plasma, a simple, fast, and sensitive tandem mass spectrometry method was established herein. Acetonitrile was used as a protein precipitation agent. Chromatographic separation was completed in 6.5 min using a BEH HILIC column (50 × 2.1 mm, 1.7 µm). The mobile phase consisted of 10 mmol/L ammonium acetate/acetonitrile (gradient elution). To quantify regadenoson and regadenoson-d3, an API 4000 mass spectrometry in multiple reaction monitoring mode with transitions of 391.3→259.2 and 394.3→262.2, respectively, was utilized. The calibration curve was linear in the range of 0.100-50.0 µg/L, and the intrabatch and interbatch precisions were <9.7% and <13.0%, respectively, and the accuracy was 2.0-6.9%. There was no apparent matrix effect for regadenoson or regadenoson-d3. The developed method was used to study the pharmacokinetic characteristics of regadenoson in healthy Chinese subjects.


Assuntos
Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Purinas , Pirazóis , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
14.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499688

RESUMO

CCCH is a zinc finger family with a typical CCCH-type motif which performs a variety of roles in plant growth and development and responses to environmental stressors. However, the information about this family has not been reported for Osmanthus fragrans. In this study, a total of 66 CCCH predicted genes were identified from the O. fragrans genome, the majority of which had multiple CCCH motifs. The 66 OfCCCHs were found to be unevenly distributed on 21 chromosomes and were clustered into nine groups based on their phylogenetic analysis. In each group, the gene structure and domain makeup were comparatively conserved. The expression profiles of the OfCCCH genes were examined in various tissues, the flower-opening processes, and under various abiotic stresses using transcriptome sequencing and qRT-PCR (quantitative real-time PCR). The results demonstrated the widespread expression of OfCCCHs in various tissues, the differential expression of 22 OfCCCHs during flower-opening stages, and the identification of 4, 5, and 13 OfCCCHs after ABA, salt, and drought stress treatment, respectively. Furthermore, characterization of the representative OfCCCHs (OfCCCH8, 23, 27, and 36) revealed that they were all localized in the nucleus and that the majority of them had transcriptional activation in the yeast system. Our research offers the first thorough examination of the OfCCCH family and lays the groundwork for future investigations regarding the functions of CCCH genes in O. fragrans.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Filogenia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Estresse Fisiológico/genética , Transcriptoma , Perfilação da Expressão Gênica
15.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361622

RESUMO

In China, Prunus mume is a famous flowering tree that has been cultivated for 3000 years. P. mume grows in tropical and subtropical regions, and most varieties lack cold resistance; thus, it is necessary to study the low-temperature response mechanism of P. mume to expand the scope of its cultivation. We used the integrated transcriptomic and metabolomic analysis of a cold-resistant variety of P. mume 'Meiren', to identify key genes and metabolites associated with low temperatures during flowering. The 'Meiren' cultivar responded in a timely manner to temperature by way of a low-temperature signal transduction pathway. After experiencing low temperatures, the petals fade and wilt, resulting in low ornamental value. At the same time, in the cold response pathway, the activities of related transcription factors up- or downregulate genes and metabolites related to low temperature-induced proteins, osmotic regulators, protective enzyme systems, and biosynthesis and metabolism of sugars and acids. Our findings promote research on the adaptation of P. mume to low temperatures during wintering and early flowering for domestication and breeding.


Assuntos
Prunus , Prunus/genética , Transcriptoma , Temperatura , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Metaboloma
16.
Cancer Cell Int ; 21(1): 573, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715862

RESUMO

Peripheral T-cell lymphoma(PTCL) is a group of lymphoproliferative tumors originated from post-thymic T cells or mature natural killer (NK) cells. It shows highly aggressive clinical behaviour, resistance to conventional chemotherapy, and a poor prognosis. Although a few prognostic models of PTCL have been established in retrospective studies, some high-risk patients still can not be screened out. Therefor we retrospectively studied 347 newly diagnosed PTCL patients and assessed the prognostic role of lymphocyte-monocyte ratio (LMR) and platelet-monocyte ratio (PMR) in the complete response (CR) and survival of PTCL patients. Patients with LMR ≤ 1.68 and PMR ≤ 300 achieved a lower CR rate and a poor survival. In multivariate analysis, LMR ≤ 1.68 (HR = 1.751, 95% CI 1.158-2.647, p < 0.05) and PMR ≤ 300 (HR = 1.762, 95% CI 1.201-2.586, p < 0.05) were independently associated with short survival. On this basis, a new prognostic model of PTCL was established to screen out high-risk patients. In our "Peripheral Blood Score (PBS)" model, three groups were identified at low risk (178 patients, 51.3%, score 0), intermediate risk (85 patients, 24.5%, score 1), and high risk (84 patients, 24.2%, score 2), having a 1-year OS of 86%, 55.3% and 22.6% (p < 0.05), and a 3-year OS of 43.4%, 20% and 13.1% (p < 0.05), respectively. Optimal strategies for identifying high-risk patients with PTCL are urgently needed. Our new PBS model is simple, inexpensive and widely available to screen out the high risk patients.

17.
Phys Chem Chem Phys ; 23(24): 13503-13511, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34120157

RESUMO

Carbon nanomaterials play important roles in modern scientific research. Integrating different carbon-based building blocks into nano-hybrid architectures not only takes full advantage of each component, but also brings in novel interfacial properties. Herein, we have employed density functional theory (DFT) calculations to investigate the effects of polymerization degree of coronene molecules encapsulated in single-walled carbon nanotubes (SWNTs) (19,0) on their interfacial properties. The present results reveal that the interfacial properties of the formed heterojunctions are remarkably regulated by the polymerization degree. For example, monomer- and dimer-encapsulated SWNTs are type-I heterojunctions in which interfacial excitation energy transfer is preferred, whereas interfacial charge carrier transfer is favorable in trimer- and polymer-encapsulated SWNTs because they are type-II heterojunctions. On the other hand, we have employed the time-domain nonadiabatic dynamics simulation approach to explore the interfacial carrier dynamics in type-II polymer-encapsulated SWNT heterojunctions. It is found that the electron and hole transfer processes are asymmetric and occur in opposite directions and at different rates. The former takes place from polymers to SWNTs in an ultrafast way (ca. 370 fs), whereas the latter occurs slowly from SWNTs to polymers (ca. 24 ps). A closer analysis uncovers the fact that the different carrier transfer rates mainly originate from the different densities of the acceptor states, energy differences and inter-state couplings between the donor and acceptor states. Finally, the present work demonstrates that the polymerization degree could act as a new regulating strategy to tune the interfacial properties of molecule-encapsulated SWNT heterojunctions.

18.
Angew Chem Int Ed Engl ; 60(34): 18688-18693, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34097335

RESUMO

Phytochrome proteins are light receptors that play a pivotal role in regulating the life cycles of plants and microorganisms. Intriguingly, while cyanobacterial phytochrome Cph1 and cyanobacteriochrome AnPixJ use the same phycocyanobilin (PCB) chromophore to absorb light, their excited-state behavior is very different. We employ multiscale calculations to rationalize the different early photoisomerization mechanisms of PCB in Cph1 and AnPixJ. We found that their electronic S1 , T1 , and S0 potential minima exhibit distinct geometric and electronic structures due to different hydrogen bond networks with the protein environment. These specific interactions influence the S1 electronic structures along the photoisomerization paths, ultimately leading to internal conversion in Cph1 but intersystem crossing in AnPixJ. This explains why the excited-state relaxation in AnPixJ is much slower (ca. 100 ns) than in Cph1 (ca. 30 ps). Further, we predict that efficient internal conversion in AnPixJ can be achieved upon protonating the carboxylic group that interacts with PCB.


Assuntos
Proteínas de Bactérias/química , Cianobactérias/química , Fotorreceptores Microbianos/química , Ficobilinas/química , Ficocianina/química , Fitocromo/química , Proteínas Quinases/química , Proteínas de Bactérias/metabolismo , Cianobactérias/metabolismo , Ligação de Hidrogênio , Estrutura Molecular , Processos Fotoquímicos , Fotorreceptores Microbianos/metabolismo , Ficobilinas/metabolismo , Ficocianina/metabolismo , Fitocromo/metabolismo , Proteínas Quinases/metabolismo , Estereoisomerismo
19.
Cancer Cell Int ; 19: 245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572062

RESUMO

BACKGROUND: Recently, some studies reported the prognostic value of platelet-to-lymphocyte ratio (PLR) in patients with diffuse large B-cell lymphoma (DLBCL), however, the results varied from different studies. Therefore, we performed a meta-analysis to explore the prognostic value of PLR in DLBCL. METHODS: A comprehensive literature retrieval was conducted by using PubMed, Embase, Web of Science, the Cochrane Library, the China National Knowledge Infrastructure (CNKI), and Wanfang. Pooled hazard ratio (HR) and 95% confidence interval (CI) were used to evaluate the association of PLR and overall survival (OS) and progression-free survival (PFS). Odd ratios (ORs) and 95% CIs for clinicopathological characteristics were statistically analyzed. RESULTS: Eight studies with 1931 patients were included for meta-analysis. The pooled analysis indicated that elevated PLR was significantly associated with poor OS (HR = 1.73, 95% CI 1.29-2.31, p < 0.001), but not PFS (HR = 0.85, 95% CI 0.57-1.27, p = 0.438). Furthermore, elevated PLR was significantly associated with presentation of B symptoms (OR = 2.27, 95% CI 1.29-3.98, p = 0.004), elevated lactate dehydrogenase (LDH) (OR = 2.76, 95% CI 2.05-3.72, p < 0.001), higher tumor stage (OR = 2.22, 95% CI 1.66-2.98, p < 0.001), and Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥ 2 (OR = 1.71, 95% CI 1.09-2.69, p = 0.019). However, elevated PLR was not significantly correlated with gender, age or cell of origin. CONCLUSION: This meta-analysis revealed that PLR may be an effective and noninvasive biomarker for poor prognosis and aggressive disease characteristics for patients with DLBCL.

20.
J Phys Chem A ; 123(29): 6144-6151, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31246461

RESUMO

Herein, we have employed OM2/MRCI-based full-dimensional nonadiabatic dynamics simulations to explore the photoisomerization and subsequent excited-state decay of a macrocyclic cyclobiazobenzene molecule. Two S1/S0 conical intersection structures are found to be responsible for the excited-state decay. Related to these two conical intersections, we found two stereoselective photoisomerization and excited-state decay pathways, which correspond to the clockwise and counterclockwise rotation motions with respect to the N═N bond of the azo group. In both pathways, the excited-state isomerization is ultrafast and finishes within ca. 69 fs, but the clockwise isomerization channel is much more favorable than the counterclockwise one with a ratio of 74% versus 26%. Importantly, the present work demonstrates that stereoselective pathways exist not only in the photoisomerization of isolated azobenzene (AB)-like systems but also in macrocyclic systems with multiple ABs. This finding could provide useful insights for understanding and controlling the photodynamics of macrocyclic nanostructures with AB units as the main building units.

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