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1.
Genome Res ; 33(10): 1818-1832, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37730437

RESUMO

The subventricular zone (SVZ) is a neurogenic niche that contributes to homeostasis and repair after brain injury. However, the effects of mild traumatic brain injury (mTBI) on the divergence of the regulatory DNA landscape within the SVZ and its link to functional alterations remain unexplored. In this study, we mapped the transcriptome atlas of murine SVZ and its responses to mTBI at the single-cell level. We observed cell-specific gene expression changes following mTBI and unveiled diverse cell-to-cell interaction networks that influence a wide array of cellular processes. Moreover, we report novel neurogenesis lineage trajectories and related key transcription factors, which we validate through loss-of-function experiments. Specifically, we validate the role of Tcf7l1, a cell cycle gene regulator, in promoting neural stem cell differentiation toward the neuronal lineage after mTBI, providing a potential target for regenerative medicine. Overall, our study profiles an SVZ transcriptome reference map, which underlies the differential cellular behavior in response to mTBI. The identified key genes and pathways that may ameliorate brain damage or facilitate neural repair serve as a comprehensive resource for drug discovery in the context of mTBI.


Assuntos
Lesões Encefálicas Traumáticas , Células-Tronco Neurais , Animais , Camundongos , Transcriptoma , Células-Tronco Neurais/metabolismo , Neurônios , Diferenciação Celular , Neurogênese/fisiologia , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo
2.
J Clin Immunol ; 42(6): 1280-1292, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35596857

RESUMO

Ras-related C3 botulinum toxin substrate 2 (RAC2) is a GTPase exclusively expressed in hematopoietic cells that acts as a pivotal regulator of several aspects of cell behavior via various cellular processes. RAC2 undergoes a tightly regulated GTP-binding/GTP-hydrolysis cycle, enabling it to function as a molecular switch. Mutations in RAC2 have been identified in 18 patients with different forms of primary immunodeficiency, ranging from phagocyte defects caused by dominant negative mutations to common variable immunodeficiency resulting from autosomal recessive loss-of-function mutations, or severe combined immunodeficiency due to dominant activating gain-of-function mutations. Here, we describe an 11-year-old girl with combined immunodeficiency presenting with recurrent respiratory infections and bronchiectasis. Immunological investigations revealed low T-cell receptor excision circle/K-deleting recombination excision circles numbers, lymphopenia, and low serum immunoglobulin G. Targeted next-generation sequencing identified a novel heterozygous mutation in RAC2, c.86C > G (p.P29R), located in the highly conserved Switch I domain. The mutation resulted in enhanced reactive oxygen species production, elevated F-actin content, and increased RAC2 protein expression in neutrophils, as well as increased cytokine production and a dysregulated phenotype in T lymphocytes. Furthermore, the dominant activating RAC2 mutation led to accelerated apoptosis with augmented intracellular active caspase 3, impaired actin polarization in lymphocytes and neutrophils, and diminished RAC2 polarization in neutrophils. We present a novel RAC2 gain-of-function mutation with implications for immunodeficiency and linked to functional dysregulation, including abnormal apoptosis and cell polarization arising from altered RAC2 expression. Thus, our findings broaden the spectrum of known RAC2 mutations and their underlying mechanisms.


Assuntos
Toxinas Botulínicas , Doenças da Imunodeficiência Primária , Actinas/genética , Actinas/metabolismo , Toxinas Botulínicas/genética , Toxinas Botulínicas/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Citocinas/metabolismo , Mutação com Ganho de Função , Guanosina Trifosfato/metabolismo , Humanos , Imunoglobulina G/metabolismo , Mutação/genética , Doenças da Imunodeficiência Primária/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Proteínas rac de Ligação ao GTP/genética , Proteínas rac de Ligação ao GTP/metabolismo
3.
J Clin Immunol ; 42(4): 837-850, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35296988

RESUMO

PURPOSE: Activated phosphoinositide 3-kinase δ syndrome (APDS) is a primary immunodeficiency first described in 2013, which is caused by gain-of-function mutations in PIK3CD or PIK3R1, and characterized by recurrent respiratory tract infections, lymphoproliferation, herpesvirus infection, autoimmunity, and enteropathy. We sought to review the clinical phenotypes, immunological characteristics, treatment, and prognosis of APDS in a large genetically defined Chinese pediatric cohort. METHODS: Clinical records, radiology examinations, and laboratory investigations of 40 APDS patients were reviewed. Patients were contacted via phone call to follow up their current situation. RESULTS: Sinopulmonary infections and lymphoproliferation were the most common complications in this cohort. Three (10.3%) and five (12.5%) patients suffered localized BCG-induced granulomatous inflammation and tuberculosis infection, respectively. Twenty-seven patients (67.5%) were affected by autoimmunity, while malignancy (7.5%) was relatively rare to be seen. Most patients in our cohort took a combined treatment of anti-infection prophylaxis, immunoglobulin replacement, and immunosuppressive therapy such as glucocorticoid or rapamycin administration. Twelve patients underwent hematopoietic stem cell transplantation (HSCT) and had a satisfying prognosis. CONCLUSION: Clinical spectrum of APDS is heterogeneous. This cohort's high incidence of localized BCG-induced granulomatous inflammation and tuberculosis indicates Mycobacterial susceptibility in APDS patients. Rapamycin is effective in improving lymphoproliferation and cytopenia. HSCT is an option for those who have severe complications and poor response to other treatments.


Assuntos
Doenças da Imunodeficiência Primária , Vacina BCG/efeitos adversos , Criança , China/epidemiologia , Classe I de Fosfatidilinositol 3-Quinases/imunologia , Humanos , Inflamação/etiologia , Doenças da Imunodeficiência Primária/complicações , Doenças da Imunodeficiência Primária/diagnóstico , Doenças da Imunodeficiência Primária/tratamento farmacológico , Doenças da Imunodeficiência Primária/imunologia , Sirolimo/uso terapêutico , Tuberculose/etiologia
4.
Int J Legal Med ; 136(6): 1737-1743, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36083564

RESUMO

Next-generation sequencing and single-cell RNA sequencing (scRNA-seq) technologies have advanced rapidly in recent years. scRNA-seq reveals the unique gene expression of each cell type, providing directions for exploring cell heterogeneity, cell type-specific responses to injury/disease, and the mechanisms underlying these processes. The development of sequencing technology and improved sequencing throughput have brought about a revolution in single-cell transcriptome study, bringing great benefits to the fields of medicine and biomedical science. From our perspective, certain issues in forensic medicine may potentially be addressed using single-cell transcriptome studies; however, this powerful technique has not yet attracted sufficient attention in forensic medicine-associated research. Therefore, examining and reviewing the latest developments and applications of single-cell transcriptome studies, we present our views on the future directions of forensic research using this technology, aiming to expand the frontiers of forensic science.


Assuntos
Análise de Célula Única , Transcriptoma , Medicina Legal , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos
5.
Photochem Photobiol Sci ; 21(8): 1481-1495, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35578152

RESUMO

Irradiation of coumarin-3-carboxylic acid in acetonitrile and methanol solutions at 355 nm results in complex multistep photochemical transformations, strongly dependent on the solvent properties and oxygen content. A number of reaction intermediates, which themselves undergo further (photo)chemical reactions, were identified by steady-state and transient absorption spectroscopy, mass spectrometry, and NMR and product analyses. The triplet excited compound in acetonitrile undergoes decarboxylation to give a 3-coumarinyl radical that traps molecular oxygen to form 3-hydroxycoumarin as the major but chemically reactive intermediate. This compound is oxygenated by singlet oxygen, produced by coumarin-3-carboxylic acid sensitization, followed by a pyrone ring-opening reaction to give an oxalic acid derivative. The subsequent steps lead to the production of salicylaldehyde, carbon monoxide, and carbon dioxide as the final products. When 3-coumarinyl radical is not trapped by oxygen in degassed acetonitrile, it abstracts hydrogen from the solvent and undergoes triplet-sensitized [2 + 2] cycloaddition. The reaction of 3-coumarinyl radical with oxygen is largely suppressed in aerated methanol as a better H-atom donor, and coumarin is obtained as the primary product in good yields. Because coumarin derivatives are used in many photophysical and photochemical applications, this work provides detailed and sometimes surprising insights into their complex phototransformations.


Assuntos
Cumarínicos , Metanol , Acetonitrilas/química , Oxigênio , Solventes/química
6.
Inorg Chem ; 60(17): 13041-13050, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34375075

RESUMO

The zeolitic imidazolate framework (ZIF)-67 microcrystal was employed as a precursor to synthesize the hollow ZIF-8/ZIF-67 composite via the epitaxial growth of ZIF-8 on ZIF-67, in situ self-sacrifice, and excavation of ZIF-67. The hollow ZIF-8/ZIF-67 composite was successfully transformed to the ZnO-Co3O4/N-C cage by thermal treatment, which was further used as the catalyst for the oxidative degradation of bisphenol A (BPA) in the presence of potassium persulfate (PS). In comparison with the Co3O4/N-C and Co3O4 obtained from pure ZIF-67 and cobalt nitrate, the ZnO-Co3O4/N-C cage demonstrated a more than four fold-higher activity and robust reusability. Based on structural analysis, the enhanced catalytic performance could be ascribed to the small, highly dispersed cobalt oxide particles, the hollow structure that facilitated the transportation of the molecules, and the synergistic effect between cobalt oxide and nitrogen-doped carbon in the composite. Besides, the effect of dosage of PS, BPA, and the co-existing components such as chloride ion, methanol, and t-butyl alcohol was carefully investigated to propose the possible mechanism. This study would give new insights into the design of functional composite materials from metal organic frameworks and the development of their application in environmental pollution disposal.

7.
J Clin Immunol ; 40(2): 378-387, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31953711

RESUMO

PURPOSE: Activated PI3Kδ syndrome 1 is a primary immunodeficiency disease, usually caused by heterozygous mutations in PIK3CD. We aimed to identify the cause of homozygous mutation at c.G3061A (p.E1021K) in a patient and the effect of allele dose in this mutation. METHODS: Genomic DNA from the parent-child trio was analyzed by next-generation sequencing. We performed phenotypic analyses in the patient and in Pik3cdE1024K+/+ mice. RESULTS: The patient was a girl harboring a homozygous mutation for p.E1021K in PIK3CD. At the age of 2 months, she began experiencing respiratory tract infections and lymphoproliferation, accompanied by bronchiectasis and extensive atelectasis in the lungs. She suffered from Haemophilus influenzae and Cytomegalovirus infections and experienced restricted growth and development. Whole-exome sequencing showed a region that included PIK3CD, with loss of heterozygosity (LOH) in chromosome 1 of the patient. The patient had not inherited any allele from her father in the LOH region. Copy number variation analysis showed no changes in the patient's father and the patient. Ultra-deep sequencing of genomic DNA from the patient's mother showed that the mutant allele frequency for c.G3061A was 1.64%. Thus, the presence of segmental maternal uniparental disomy and maternal gonosomal mosaicism resulted in the homozygous mutation. Lymphadenopathy, differentiation of activated T cells, and follicular B cells lymphopenia were found to be more prominent in Pik3cdE1024+/+ mice than in Pik3cdE1024+/- mice. CONCLUSION: This report showed the coexistence of uniparental disomy and mosaicism in PIK3CD. Some immunological features were seen to be allele dose-dependent in the presence of p.E1021K mutation.


Assuntos
Cromossomos Humanos Par 1/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação/genética , Doenças da Imunodeficiência Primária/genética , Linfócitos T/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Lactente , Perda de Heterozigosidade , Ativação Linfocitária , Camundongos , Camundongos Knockout , Linhagem , Dissomia Uniparental
8.
Photosynth Res ; 136(3): 315-328, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29159723

RESUMO

Comparing with other angiosperms, most members within the family Orchidaceae have lower photosynthetic capacities. However, the underlying mechanisms remain unclear. Cypripedium and Paphiopedilum are closely related phylogenetically in Orchidaceae, but their photosynthetic performances are different. We explored the roles of internal anatomy and diffusional conductance in determining photosynthesis in three Cypripedium and three Paphiopedilum species, and quantitatively analyzed their diffusional and biochemical limitations to photosynthesis. Paphiopedilum species showed lower light-saturated photosynthetic rate (A N), stomatal conductance (g s), and mesophyll conductance (g m) than Cypripedium species. A N was positively correlated with g s and g m. And yet, in both species A N was more strongly limited by g m than by biochemical factors or g s. The greater g s of Cypripedium was mainly affected by larger stomatal apparatus area and smaller pore depth, while the less g m of Paphiopedilum was determined by the reduced surface area of mesophyll cells and chloroplasts exposed to intercellular airspace per unit of leaf area, and much thicker cell wall thickness. These results suggest that leaf anatomical structure is the key factor affecting g m, which is largely responsible for the difference in photosynthetic capacity between those two genera. Our findings provide new insight into the photosynthetic physiology and functional diversification of orchids.


Assuntos
Orchidaceae/anatomia & histologia , Orchidaceae/fisiologia , Fotossíntese/fisiologia , Cloroplastos/metabolismo , Difusão , Células do Mesofilo/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/fisiologia , Transpiração Vegetal/fisiologia , Especificidade da Espécie
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(6): 819-823, 2017 Nov.
Artigo em Zh | MEDLINE | ID: mdl-29260513

RESUMO

OBJECTIVE: To study the epigenetic regulation of pancreatic carcinoma related microRNA (miR34a,miR34b,miR148a and miR203a) expression by gene promoter methylation,and its effect on the proliferation,migration and invasion of pancreatic carcinoma cells. METHODS: The pancreatic carcinoma cells were divided into two groups:control group and treatment group.Control group was treated with 0 µmol/L DNA methyltransferase inhibitor 5-Aza-CdR and treatment group was treated with 60 µmol/L 5-Aza-CdR. The methylation status of microRNA gene promoter regions was detected by MSP (methylation-specific PCR). The microRNAs' expression levels were evaluated by real-time PCR. The CCK-8 assay,wound healing assay and Transwell assay were employed to study the proliferation,migration and invasion of pancreatic carcinoma cells,respectively. RESULTS: The results of MSP showed that the methylated band of the treated group was weaker than that of the untreated group and the unmethylated band of the treated group was stronger than that of the untreated group. Real-time PCR results showed that the relative expression levels of microRNAs in the treatment group were higher than those in the control group ( P<0.05). The CCK-8 assay showed that inhibition rate of the treatment group showed dose-dependent effect with the increase of drug concentration. Wound healing assay showed that the wound healing rate of Treatment group was lower than that of untreated group ( P<0.01). The results of transwell assay showed that the number of migrated cells in the treated group was less than that in the untreated group ( P<0.01). CONCLUSION: Decreased methylation levels in microRNA promoter region caused by 5-Aza-CdR treatment increased the expression of miR34a,miR34b ,miR148a and miR203a,leading to inhibition of the proliferation,migration and invasion of pancreatic carcinoma cells.


Assuntos
Metilação de DNA , Epigênese Genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Azacitidina , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Regiões Promotoras Genéticas , Neoplasias Pancreáticas
10.
J Obstet Gynaecol Res ; 41(12): 1959-64, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26554540

RESUMO

AIM: Recent studies have demonstrated that the neural precursor cell expressed, developmentally downregulated 4-like (Nedd4L) gene plays a role in the progression of various cancers. However, reports describing Nedd4L expression in ovarian cancer tissues are limited. MATERIAL AND METHODS: A cohort (n = 117) of archival formalin-fixed, paraffin embedded resected normal ovarian epithelial tissues (n = 10), benign ovarian epithelial tumor tissues (n = 10), serous borderline ovarian epithelial tumor tissues (n = 14), mucous borderline ovarian epithelial tumor tissues (n = 11), and invasive ovarian epithelial cancer tissues (n = 72) were assessed for Nedd4L protein expression using immunohistochemistry. RESULTS: Nedd4L protein expression was significantly decreased in invasive ovarian epithelial cancer tissues compared to non-cancer tissues (P < 0.05). Decreased Nedd4L protein expression correlated with clinical stage, pathological grade, lymph node metastasis and survival (P < 0.05). CONCLUSION: Nedd4L protein expression may be an independent prognostic marker of ovarian cancer development.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/análise , Neoplasias Epiteliais e Glandulares/química , Neoplasias Ovarianas/química , Ovário/química , Ubiquitina-Proteína Ligases/análise , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma Epitelial do Ovário , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Ubiquitina-Proteína Ligases Nedd4 , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Ubiquitina-Proteína Ligases/fisiologia
11.
Planta ; 240(3): 489-96, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24915747

RESUMO

MAIN CONCLUSION: Modifications in leaf anatomy of tobacco plants induced greater leaf water transport capacity, meeting greater transpirational demands and acclimating to warmer temperatures with a higher vapor pressure deficit. Temperature is one of the most important environmental factors affecting photosynthesis and growth of plants. However, it is not clear how it may alter leaf hydraulic architecture. We grew plants of tobacco (Nicotiana tabacum) 'k326' in separate glasshouse rooms set to different day/night temperature conditions: low (LT 24/18 °C), medium (MT 28/22 °C), or high (HT 32/26 °C). After 40 days of such treatment, their leaf anatomies, leaf hydraulics, photosynthetic rates, and instantaneous water-use efficiency (WUEi) were measured. Compared with those under LT, plants exposed to HT or MT conditions had significantly higher values for minor vein density (MVD), stomatal density (SD), leaf area, leaf hydraulic conductance (K leaf), and light-saturated photosynthetic rate (A sat), but lower values for leaf water potential (ψ l) and WUEi. However, those parameters did not differ significantly between HT and MT conditions. Correlation analyses demonstrated that SD and K leaf increased in parallel with MVD. Moreover, greater SD and K leaf were partially associated with accelerated stomatal conductance. And then stomatal conductance was positively correlated with A sat. Therefore, under well-watered, fertilized conditions, when relative humidity was optimal, changes in leaf anatomy seemed to facilitate the hydraulic acclimation to higher temperatures, meeting greater transpirational demands and contributing to the maintenance of great photosynthetic rates. Because transpiration rate increased more with temperature than photosynthetic rate, WUEi reduced under warmer temperatures. Our results indicate that the modifications of leaf hydraulic architecture are important anatomical and physiological strategies for tobacco plants acclimating to warmer temperatures under a higher vapor pressure deficit.


Assuntos
Aclimatação , Nicotiana/anatomia & histologia , Folhas de Planta/anatomia & histologia , Transpiração Vegetal , Água/fisiologia , Temperatura Alta , Fotossíntese , Folhas de Planta/fisiologia , Nicotiana/fisiologia
12.
Adv Sci (Weinh) ; : e2401767, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713745

RESUMO

Electromagnetic (EM) metamaterials have garnered considerable attention due to their capacity to achieve negative parameters, significantly influencing the integration of natural materials with artificially structural media. The emergence of carbon aerogels (CAs) offers an opportunity to create lightweight EM metamaterials, notable for their promising EM shielding or absorption effects. This paper introduces an efficient, low-cost method for fabricating CAs without requiring stringent drying conditions. By finely tuning the ZnCl2/lignin ratio, the porosity is controlled in CAs. This control leads to an epsilon-negative response in the radio-frequency region, driven by the intrinsic plasmonic state of the 3D carbon network, as opposed to traditional periodic building blocks. This approach yields a tunable and weakly epsilon-negative response, reaching an order of magnitude of -103 under MHz frequencies. Equivalent circuit analysis highlights the inductive characteristics of CAs, correlating their significant dielectric loss at low frequencies. Additionally, EM simulations are performed to evaluate the distribution of the electric field vector in epsilon-negative CAs, showcasing their potential for effective EM shielding. The lignin-derived, lightweight CAs with their tunable epsilon-negative response hold promise for pioneering new directions in EM metamaterials and broadening their application in diverse extreme conditions.

13.
J Control Release ; 371: 324-337, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823584

RESUMO

There is an urgent clinical need to develop nerve-blocking agents capable of inducing long duration sensory block without muscle weakness or paralysis to treat post-operative and chronic pain conditions. Here, we report a galacturonic acid-capsaicin (GalA-CAP) prodrug as an effective nociceptive-selective axon blocking agent. Capsaicin selectively acts on nociceptive signaling without motor nerve blockade or disruption of proprioception and touch sensation, and the galacturonic acid moiety enhance prodrug permeability across the restrictive peripheral nerve barriers (PNBs) via carrier-mediated transport by the facilitative glucose transporters (GLUTs). In addition, following prodrug transport across PNBs, the inactive prodrug is converted to active capsaicin through linker hydrolysis, leading to sustained drug release. A single injection of GalA-CAP prodrug at the sciatic nerves of rats led to nociceptive-selective nerve blockade lasting for 234 ± 37 h, which is a sufficient duration to address the most intense period of postsurgical pain. Furthermore, the prodrug markedly mitigated capsaicin-associated side effects, leading to a notable decrease in systemic toxicity, benign local tissue reactions, and diminished burning and irritant effects.


Assuntos
Capsaicina , Bloqueio Nervoso , Pró-Fármacos , Ratos Sprague-Dawley , Nervo Isquiático , Pró-Fármacos/administração & dosagem , Animais , Capsaicina/administração & dosagem , Capsaicina/análogos & derivados , Masculino , Nervo Isquiático/efeitos dos fármacos , Bloqueio Nervoso/métodos , Ratos , Analgésicos/administração & dosagem , Analgésicos/farmacologia
14.
J Hazard Mater ; 471: 134422, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38677118

RESUMO

Electron transfer pathways have been verified as overriding regimes when peroxydisulfate (PDS) was activated by porous carbon. The incorporation of graphitic structure into carbon matrix was favorable to the rapid electron transfer, but excessive graphitization would deteriorate the specific surface area (SSA), weakening the catalytic performance. The reasonable trade-off between SSA and graphitization degree was necessary and challenging for the preparation of efficient carbon based PS-activators. Herein, a series of graphitic porous carbon with discrepant SSA and graphitic structure were fabricated. The incorporation of graphitization tracks into ultra-thin edges on porous carbon film was verified by multifarious structural characterization. After trade-off, the optimum catalyst exhibited superior catalytic performance with degradation rate constant (kobs) exceeding that of ungraphitized precursor by up to 16.0 times. Mechanistic investigations substantiated that the sufficient SSA of catalyst provided favorable conditions for its affinity towards PDS and sulfadiazine (SDZ), resulting in the formation of PDS* complexes and SDZ adsorption, while the appropriate graphitization degree ensured the reinforced electron transfer rate, which collectively accelerated SDZ oxidation through electron-transfer pathway. The multivariate linear regression model linking kobs to SSA and graphitization degree was established providing basis to construct efficient catalysts for PDS activation.

15.
Physiol Plant ; 149(1): 141-50, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23480306

RESUMO

Photorespiration has been indicated as an important mechanism for maintaining CO2 assimilation and alleviating photodamage under conditions of high light and low CO2 . We tested the hypothesis that plants grown under a high temperature had greater electron flow for photorespiration compared with those grown under a relative low temperature. Responses of photosynthetic electron flow and CO2 assimilation to incident light intensity and intercellular CO2 concentration were examined in leaves of tobacco cultivar 'k326'. Plants were cultivated at three sites with different ambient temperatures (Zhengzhou, Zunyi and Jiangchuan). Under high light, plants grown in Zhengzhou (with the highest growth temperature in the three sites) showed higher effective quantum yield of photosystem II and total electron flow through photosystem II than that in Zunyi and Jiangchuan. However, regardless of light intensity and intercellular CO2 status, there were no significant differences among sites in the photosynthetic CO2 assimilation rate or electron flow devoted to the carboxylation of ribulose-1,5-bisphosphate (RuBP). As a result, plants grown at high temperature showed higher electron flow devoted to oxygenation of RuBP than plants grown at low temperature. These results suggested that enhancement of electron flow for photorespiration is an important strategy in tobacco for acclimating to high growth temperature.


Assuntos
Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Folhas de Planta/fisiologia , Aclimatação , Dióxido de Carbono/metabolismo , Transporte de Elétrons/fisiologia , Luz , Fotossíntese/fisiologia , Complexo de Proteína do Fotossistema II/metabolismo , Ribulosefosfatos/metabolismo , Temperatura
16.
Oecologia ; 173(3): 721-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23636462

RESUMO

The relative advantages of being deciduous or evergreen in subtropical forests and the relationship between leaf phenology and nutrient resorption efficiency are not well understood. The most successful deciduous species (Lyonia ovalifolia) in an evergreen-dominated subtropical montane cloud forest in southwest (SW) China maintains red senescing leaves throughout much of the winter. The aim of this study was to investigate whether red senescing leaves of this species were able to assimilate carbon in winter, to infer the importance of maintaining a positive winter carbon balance in subtropical forests, and to test whether an extended leaf life span is associated with enhanced nutrient resorption and yearly carbon gain. The red senescing leaves of L. ovalifolia assimilated considerable carbon during part of the winter, resulting in a higher yearly carbon gain than co-occurring deciduous species. Its leaf N and P resorption efficiency was higher than for co-occurring non-anthocyanic deciduous species that dropped leaves in autumn, supporting the hypothesis that anthocyanin accumulation and/or extended leaf senescence help in nutrient resorption. Substantial winter carbon gain and efficient nutrient resorption may partially explain the success of L. ovalifolia versus that of the other deciduous species in this subtropical forest. The importance of maintaining a positive carbon balance for ecological success in this forest also provides indirect evidence for the dominance of evergreen species in the subtropical forests of SW China.


Assuntos
Adaptação Biológica/fisiologia , Envelhecimento/fisiologia , Ericaceae/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Estações do Ano , Árvores/fisiologia , Análise de Variância , Antocianinas/metabolismo , Carbono/metabolismo , China , Nitrogênio/metabolismo , Fósforo/metabolismo , Chuva , Especificidade da Espécie
17.
Sci Data ; 10(1): 638, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730716

RESUMO

As a significant type of traumatic brain injury (TBI), blast-induced traumatic brain injury (bTBI) frequently results in severe neurological and psychological impairments. Due to its unique mechanistic and clinical features, bTBI presents diagnostic and therapeutic challenges compared to other TBI forms. The hippocampus, an important site for secondary injury of bTBI, serves as a key niche for neural regeneration and repair post-injury, and is closely associated with the neurological outcomes of bTBI patients. Nonetheless, the pathophysiological alterations of hippocampus underpinning bTBI remain enigmatic, and a corresponding transcriptomic dataset for research reference is yet to be established. In this investigation, the single-nucleus RNA sequencing (snRNA-seq) technique was employed to sequence individual hippocampal nuclei of mice from bTBI and sham group. Upon stringent quality control, gene expression data from 17,278 nuclei were obtained, with the dataset's reliability substantiated through various analytical methods. This dataset holds considerable potential for exploring secondary hippocampal injury and neurogenesis mechanisms following bTBI, with important reference value for the identification of specific diagnostic and therapeutic targets for bTBI.


Assuntos
Lesões Encefálicas Traumáticas , Transcriptoma , Animais , Camundongos , Lesões Encefálicas Traumáticas/genética , Perfilação da Expressão Gênica , Hipocampo , Reprodutibilidade dos Testes
18.
Sci Data ; 10(1): 13, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604452

RESUMO

Explosive blast-related traumatic brain injuries (bTBI) are common in war zones and urban terrorist attacks. These bTBIs often result in complex neuropathologic damage and neurologic complications. However, there is still a lack of specific strategies for diagnosing and/or treating bTBIs. The sub-ventricular zone (SVZ), which undergoes adult neurogenesis, is critical for the neurological maintenance and repair after brain injury. However, the cellular responses and mechanisms that trigger and modulate these activities in the pathophysiological processes following bTBI remain poorly understood. Here we employ single-nucleus RNA-sequencing (snRNA-seq) of the SVZ from mice subjected to a bTBI. This data-set, including 15272 cells (7778 bTBI and 7494 control) representing all SVZ cell types and is ideally suited for exploring the mechanisms underlying the pathogenesis of bTBIs. Additionally, it can serve as a reference for future studies regarding the diagnosis and treatment of bTBIs.


Assuntos
Traumatismos por Explosões , Lesões Encefálicas Traumáticas , Lesões Encefálicas , Animais , Camundongos , Traumatismos por Explosões/complicações , Traumatismos por Explosões/patologia , Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Lesões Encefálicas Traumáticas/complicações
19.
Nutrition ; 109: 111992, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36871445

RESUMO

Ferroptosis, a newly characterized form of programmed cell death that results from lipid peroxidation and mitochondrial dysfunction, has been demonstrated to be involved in the pathogenesis of traumatic brain injury (TBI). Scientific evidence has shown that intermittent fasting (IF) reduces both the lipid peroxidation and the mitochondrial dysfunction, raising the question of whether IF affects the ferroptosis induced by TBI. Here, based on an established TBI animal model, we examine the effects of IF on the activation of ferroptosis pathway as well as related outcomes. We uncovered that a 1-mo IF elevated the protective Gpx4 and Hspb1 expression, and partly abolished the increase of Nfe2l2, Slc7a11, Alox8, Steap3, and Nox2 in the cortex, which were induced by TBI. Furthermore, the characteristic cellular damage induced by ferroptosis was alleviated by IF, as revealed by Perls' Prussian blue staining, Nissl staining, and transmission electron microscope examination. Consistently, we examined the outcomes of mice subjected to TBI and found an improved cognitive function of the IF mice. In sum, our study demonstrated, to our knowledge for the first time, that a 1-mo IF regimen partly ameliorates ferroptosis in the cortex of mice subjected to TBI, which potentially contributes to a lessening of cognitive impairment.


Assuntos
Lesões Encefálicas Traumáticas , Disfunção Cognitiva , Ferroptose , Camundongos , Animais , Jejum Intermitente , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Neurônios/metabolismo
20.
Chem Commun (Camb) ; 58(64): 8958-8961, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35856793

RESUMO

Here we report on carbon monoxide-photoreleasable compounds (photoCORMs) that combine heptamethine cyanine and flavonol chromophores and are activated upon irradiation with near-infrared light. Excellent CO-release yields and uncaging cross sections in aqueous solutions, enhanced water solubilities thanks to polar substituents or a host-guest approach using cucurbit[7]uril are demonstrated. The hybrids display outstanding biocompatibility and diverse, structure-dependent cell penetrability and internalization.


Assuntos
Monóxido de Carbono , Quinolinas , Corantes , Flavonóis , Metanol , Água
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