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1.
Mater Horiz ; 8(2): 471-500, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821265

RESUMO

Organic electrode materials have been considered as promising candidates for the next generation rechargeable battery systems due to their high theoretical capacity, versatility, and environmentally friendly nature. Among them, organosulfur compounds have been receiving more attention in conjunction with the development of lithium-sulfur batteries. Usually, organosulfide electrodes can deliver a relatively high theoretical capacity based on reversible breakage and formation of disulfide (S-S) bonds. In this review, we provide an overview of organosulfur materials for rechargeable lithium batteries, including their molecular structural design, structure related electrochemical performance study and electrochemical performance optimization. In addition, recent progress of advanced characterization techniques for investigation of the structure and lithium storage mechanism of organosulfur electrodes are elaborated. To further understand the perspective application, the additive effect of organosulfur compounds for lithium metal anodes, sulfur cathodes and high voltage inorganic cathode materials are reviewed with typical examples. Finally, some remaining challenges and perspectives of the organosulfur compounds as lithium battery components are also discussed. This review is intended to serve as general guidance for researchers to facilitate the development of organosulfur compounds.

2.
Environ Res ; 204(Pt A): 112026, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34509480

RESUMO

Mercury (Hg) biotransformation is an important process that can affect the speciation and bioaccumulation of Hg in fish. The intestinal microbiota has been suggested to take part in this process. However, Hg biotransformation in fish is still unclear and the responses of gut microbiota to different Hg exposure scenarios have not been well addressed. The present study investigated the bioaccumulation and biotransformation of Hg in a freshwater fish (Micropterus salmoides) and characterized the gut microbiome community under dietary inorganic Hg (IHg) or methylmercury (MeHg) exposure, aiming to evaluate the effects of gut microbiome's activities on the internal-handling and fate of Hg in fish. Significant Hg methylation was observed in fish under IHg exposure, whereas there was no demethylation occurred in MeHg-treated fish. Both IHg and MeHg could significantly alter the community composition of gut microbiome. The administrated IHg in the food could enhance the growth of methylators, resulting in additional MeHg production in fish gut. However, abundance of demethylators was greatly decreased under either IHg or MeHg exposure, leading the demethylation process to be negligible. The results strongly suggested that the behaviors of gut bacterial community played an important role in the presence or absence of biotransformation processes. This study elucidated the importance of gut microbiome in Hg biotransformation process, and helped to develop a novel perspective to understand the Hg bioaccumulation of fish in realistic environment.

3.
Front Immunol ; 12: 720907, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421925

RESUMO

Objective: To explore the outcomes of NMOSD attacks and investigate serum biomarkers for prognosis and severity. Method: Patients with NMOSD attacks were prospectively and observationally enrolled from January 2019 to December 2020 at four hospitals in Guangzhou, southern China. Data were collected at attack, discharge and 1/3/6 months after acute treatment. Serum cytokine/chemokine and neurofilament light chain (NfL) levels were examined at the onset stage. Results: One hundred patients with NMOSD attacks were included. The treatment comprised intravenous methylprednisolone pulse therapy alone (IVMP, 71%), IVMP combined with apheresis (8%), IVMP combined with intravenous immunoglobulin (18%) and other therapies (3%). EDSS scores decreased significantly from a medium of 4 (interquartile range 3.0-5.5) at attack to 3.5 (3.0-4.5) at discharge, 3.5 (2.0-4.0) at the 1-month visit and 3.0 (2.0-4.0) at the 3-month visit (p<0.01 in all comparisons). The remission rate was 38.0% at discharge and 63.3% at the 1-month visit. Notably, relapse occurred in 12.2% of 74 patients by the 6-month follow-up. Higher levels of T helper cell 2 (Th2)-related cytokines, including interleukin (IL)-4, IL-10, IL-13, and IL-1 receptor antagonist, predicted remission at the 1-month visit (OR=9.33, p=0.04). Serum NfL levels correlated positively with onset EDSS scores in acute-phase NMOSD (p<0.001, R2 = 0.487). Conclusions: Outcomes of NMOSD attacks were generally moderate. A high level of serum Th2-related cytokines predicted remission at the 1-month visit, and serum NfL may serve as a biomarker of disease severity at attack. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT04101058, identifier NCT04101058.

4.
mSystems ; 6(4): e0025221, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34282939

RESUMO

"Candidatus Bathyarchaeia" is a phylogenetically diverse and widely distributed lineage often in high abundance in anoxic submarine sediments; however, their evolution and ecological roles in terrestrial geothermal habitats are poorly understood. In the present study, 35 Ca. Bathyarchaeia metagenome-assembled genomes (MAGs) were recovered from hot spring sediments in Tibet and Yunnan, China. Phylogenetic analysis revealed all MAGs of Ca. Bathyarchaeia can be classified into 7 orders and 15 families. Among them, 4 families have been first discovered in the present study, significantly expanding the known diversity of Ca. Bathyarchaeia. Comparative genomics demonstrated Ca. Bathyarchaeia MAGs from thermal habitats to encode a large variety of genes related to carbohydrate degradation, which are likely a metabolic adaptation of these organisms to a lifestyle at high temperatures. At least two families are potential methanogens/alkanotrophs, indicating a potential for the catalysis of short-chain hydrocarbons. Three MAGs from Family-7.3 are identified as alkanotrophs due to the detection of an Mcr complex. Family-2 contains the largest number of genes relevant to alkyl-CoM transformation, indicating the potential for methylotrophic methanogenesis, although their evolutionary history suggests the ancestor of Ca. Bathyarchaeia was unable to metabolize alkanes. Subsequent lineages have acquired the ability via horizontal gene transfer. Overall, our study significantly expands our knowledge and understanding of the metabolic capabilities, habitat adaptations, and evolution of Ca. Bathyarchaeia in thermal environments. IMPORTANCE Ca. Bathyarchaeia MAGs from terrestrial hot spring habitats are poorly revealed, though they have been studied extensively in marine ecosystems. In this study, we uncovered the metabolic capabilities and ecological role of Ca. Bathyarchaeia in hot springs and give a comprehensive comparative analysis between thermal and nonthermal habitats to reveal the thermal adaptability of Ca. Bathyarchaeia. Also, we attempt to determine the evolutionary history of methane/alkane metabolism in Ca. Bathyarchaeia, since it appears to be the first archaea beyond Euryarchaeota which contains the mcrABG genes. The reclassification of Ca. Bathyarchaeia and significant genomic differences among different lineages largely expand our knowledge on these cosmopolitan archaea, which will be beneficial in guiding the future studies.

5.
ACS Appl Mater Interfaces ; 13(21): 24995-25001, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34010556

RESUMO

A novel electrolyte system with an excellent low-temperature performance for lithium-ion batteries (LIBs) has been developed and studied. It was discovered for the first time, in this work, that when isoxazole (IZ) was used as the main solvent, the ionic conductivity of the electrolyte for LIBs is more than doubled in a temperature range between -20 and 20 °C compared to the baseline electrolyte using ethylene carbonate-ethyl methyl carbonate as solvents. To solve the problem of solvent co-intercalation into the graphite anode and/or electrolyte decomposition, the lithium difluoro(oxalato)borate (LiDFOB) salt and fluoroethylene carbonate (FEC) additive were used to form a stable solid electrolyte interphase on the surface of the graphite anode. Benefitting from the high ionic conductivity at low temperature, cells using a new electrolyte with 1 M LiDFOB in FEC/IZ (1:10, vol %) solvents demonstrated a very high reversible capacity of 187.5 mAh g-1 at -20 °C, while the baseline electrolyte only delivered a reversible capacity of 23.1 mAh g-1.

6.
Environ Pollut ; 277: 116768, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33647808

RESUMO

Both inorganic (IHg) and organic (MeHg) forms of Hg can be converted into each other by methylation or demethylation, leading to changes of Hg speciation and distribution in fish. However, Hg biotransformation in fish is not thoroughly understood and the key factors in this process are unclear. The present study investigated the in vivo Hg transformation in a marine fish (Acanthopagrus latus) and explored the roles of intestinal microbiota in Hg biotransformation. We first demonstrated that Hg methylation or demethylation occurred in the fish gut under dietary IHg or MeHg exposure, respectively. The demethylation was observed to be faster than methylation, suggesting that demethylation could significantly influence the Hg speciation in fish. This study also strongly suggested that intestinal microbiota played a predominant role in Hg biotransformation and thus significantly affected the overall Hg accumulation and distribution in fish body. The richness of Hg methylators or demethylators was elevated under IHg or MeHg treatment, respectively. Furthermore, the intestinal microbiota composition was also altered by Hg exposure. This study highlights the importance of intestinal microbiota in Hg biotransformation in fish body, and suggests that modulating the gut microbiome could be a possible solution to minimize Hg contamination in fish.


Assuntos
Microbioma Gastrointestinal , Mercúrio , Compostos de Metilmercúrio , Animais , Biotransformação , Peixes
7.
ACS Appl Mater Interfaces ; 13(2): 2622-2629, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33410655

RESUMO

LiNi1-x-yMnxCoyO2 (NMC) is an important class of high-energy-density cathode materials. The possibility of changing both x and y in the chemical formula provides numerous materials with diverse electrochemical and structural properties. It is highly desirable to have guidance on correlating NMC structural and electrochemical properties with their chemical composition for material designing and screening. Here, using synchrotron-based X-ray diffraction, X-ray absorption spectroscopy, electrochemical characterization, and literature survey, the content difference between Mn and Co (denoted as x-y in NMC) is identified as an effective indicator to estimate Li/transition metal (Li/TM) cation mixing ratio and first-cycle Coulombic efficiency (CE). In addition, a linear relationship between oxygen position "z" and the size difference between Li+ and TM cation (normalized by the c-axis length) is found, and such linearity can be used to accurately predict the oxygen position in NMC materials by considering the average TM cation size and c-axis length. It is also concluded that the shortest O-O distance in the bulk of NMC materials could not be shorter than 2.5 Ševen at a highly charged state. Therefore, oxygen release is not likely to take place from the bulk if the structure maintains the R3 ̅m symmetry.

8.
Angew Chem Int Ed Engl ; 60(15): 8258-8267, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33480154

RESUMO

Manganese-rich layered oxide materials hold great potential as low-cost and high-capacity cathodes for Na-ion batteries. However, they usually form a P2 phase and suffer from fast capacity fade. In this work, an O3 phase sodium cathode has been developed out of a Li and Mn-rich layered material by leveraging the creation of transition metal (TM) and oxygen vacancies and the electrochemical exchange of Na and Li. The Mn-rich layered cathode material remains primarily O3 phase during sodiation/desodiation and can have a full sodiation capacity of ca. 220 mAh g-1 . It delivers ca. 160 mAh g-1 specific capacity between 2-3.8 V with >86 % retention over 250 cycles. The TM and oxygen vacancies pre-formed in the sodiated material enables a reversible migration of TMs from the TM layer to the tetrahedral sites in the Na layer upon de-sodiation and sodiation. The migration creates metastable states, leading to increased kinetic barrier that prohibits a complete O3-P3 phase transition.

9.
Nat Commun ; 11(1): 6342, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311507

RESUMO

Lithium-rich nickel-manganese-cobalt (LirNMC) layered material is a promising cathode for lithium-ion batteries thanks to its large energy density enabled by coexisting cation and anion redox activities. It however suffers from a voltage decay upon cycling, urging for an in-depth understanding of the particle-level structure and chemical complexity. In this work, we investigate the Li1.2Ni0.13Mn0.54Co0.13O2 particles morphologically, compositionally, and chemically in three-dimensions. While the composition is generally uniform throughout the particle, the charging induces a strong depth dependency in transition metal valence. Such a valence stratification phenomenon is attributed to the nature of oxygen redox which is very likely mostly associated with Mn. The depth-dependent chemistry could be modulated by the particles' core-multi-shell morphology, suggesting a structural-chemical interplay. These findings highlight the possibility of introducing a chemical gradient to address the oxygen-loss-induced voltage fade in LirNMC layered materials.

10.
Front Immunol ; 11: 2101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983166

RESUMO

Background and Purpose: The mechanism underlying the pathology of neuromyelitis optica spectrum disorders (NMOSD) remains unclear even though antibodies to the water channel protein aquaporin-4 (AQP4) on astrocytes play important roles. Our previous study showed that dysbiosis occurred in the fecal microbiota of NMOSD patients. In this study, we further investigated whether the intestinal barrier and mucosal flora balance are also interrupted in NMOSD patients. Methods: Sigmoid mucosal biopsies were collected by endoscopy from six patients with NMOSD and compared with samples from five healthy control (HC) individuals. These samples were processed for electron microscopy and immunohistochemistry to investigate changes in ultrastructure and in the number and size of intestinal inflammatory cells. Changes in mucosal flora were also analyzed by high-throughput 16S ribosomal RNA gene amplicon sequencing. Results: The results from bacterial rRNA gene sequencing showed that bacterial diversity was decreased, but Streptococcus and Granulicatella were abundant in the colonic mucosa specimens of NMOSD patients compared to the HC individuals. The intercellular space between epithelia of the colonic mucosa was wider in NMOSD patients compared to the HC subjects (p < 0.01), and the expression of tight junction proteins [occludin, claudin-1 and zonula occludens-1 (ZO-1)] in NMOSD patients significantly decreased compared to that in the HC subjects. We also found numerous activated macrophages with many inclusions within the cytoplasm, mast cells with many particles in their cytoplasm, and enlarged plasma cells with rich developed rough endoplasmic reticulum in the lamina propria of the mucosa of the patients with NMOSD. Quantitative analysis showed that the percentages of small CD38+ and CD138+ cells (plasma cells) were lower, but the percentage of larger plasma cells was higher in NMOSD patients. Conclusion: The present study demonstrated that the intestinal barrier was disrupted in the patients with NMOSD, accompanied by dysbiosis and inflammatory activation of the gut. The mucosal microbiota imbalance and inflammatory responses might allow pathogens to cross the damaged intestinal barrier and participate in pathological process in NMOSD. However, further study on the pathological mechanism of NMOSD underlying gut dysbiosis is warranted in the future.


Assuntos
Disbiose/microbiologia , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Neuromielite Óptica/microbiologia , Adulto , Bactérias/isolamento & purificação , Colo Sigmoide/microbiologia , Colo Sigmoide/patologia , Disbiose/imunologia , Fezes/microbiologia , Feminino , Humanos , Inflamação , Junções Intercelulares/ultraestrutura , Mucosa Intestinal/microbiologia , Mucosa Intestinal/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Neuromielite Óptica/imunologia , Plasmócitos/patologia , Ribotipagem , Adulto Jovem
11.
Aging (Albany NY) ; 12(12): 11781-11793, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32568100

RESUMO

Excess salt (NaCl) intake is closely related to a variety of central nervous system (CNS) diseases characterized by increased cerebral microvascular permeability. However, the link between a high salt diet (HSD) and the breakdown of tight junctions (TJs) remains unclear. In the present study, we found that high salt does not directly influence the barrier between endothelial cells, but it suppresses expression of TJ proteins when endothelial cells are co-cultured with astrocytes. This effect is independent of blood pressure, but depends on the astrocyte activation via the NFκB/MMP-9 signaling pathway, resulting in a marked increase in VEGF expression. VEGF, in turn, induces disruption of TJs by inducing phosphorylation and activation of ERK and eNOS. Correspondingly, the HSD-induced disruption of TJ proteins is attenuated by blocking VEGF using the specific monoclonal antibody Bevacizumab. These results reveal a new axis linking a HSD to increased cerebral microvascular permeability through a VEGF-initiated inflammatory response, which may be a potential target for preventing the deleterious effects of HSD on the CNS.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/patologia , Permeabilidade Capilar/efeitos dos fármacos , Cloreto de Sódio na Dieta/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Bevacizumab , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/imunologia , Permeabilidade Capilar/imunologia , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Células Endoteliais , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Cultura Primária de Células , Ratos , Cloreto de Sódio na Dieta/administração & dosagem , Organismos Livres de Patógenos Específicos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
12.
ACS Appl Mater Interfaces ; 12(14): 16040-16049, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32174109

RESUMO

Antibodies are the most common affinity reagents for specific target recognition. However, their applications are limited by high cost and low stability. Thus, seeking substitutes for antibodies is of great significance. In this work, we designed a library containing 82 self-assembled nanoparticles (SNPs) based on the self-assembly of ß-cyclodextrin polymers and adamantane derivatives, and then screened out eight types of SNPs capable of suppressing the toxicity of melittin using a hemolytic activity neutralization assay. The affinities of the SNPs to melittin were demonstrated using surface plasmon resonance (SPR). As evidenced by cytotoxicity experiments, SNPs could also suppress the toxicity of melittin to other cells. In addition, to verify the universality of our method, 11 types of SNPs capable of neutralizing another toxic peptide, phenolic soluble polypeptide (PSMα3) secreted by Staphylococcus aureus, were selected from the same SNP library. Our self-assembly-based method for the library preparation has the advantages of flexible design, mild experimental condition, and simple operation, which is expected to seek artificial affinity reagents for more species.


Assuntos
Anticorpos/imunologia , Meliteno/química , Nanopartículas/química , Staphylococcus aureus/química , Anticorpos/química , Testes Imunológicos de Citotoxicidade , Humanos , Polímeros/química , Ressonância de Plasmônio de Superfície , beta-Ciclodextrinas/química
13.
J Neuroinflammation ; 16(1): 242, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779652

RESUMO

BACKGROUND: Preserving the integrity of the blood-brain barrier (BBB) is beneficial to avoid further brain damage after acute ischemic stroke (AIS). Astrocytes, an important component of the BBB, promote BBB breakdown in subjects with AIS by secreting inflammatory factors. The glucagon-like peptide-1 receptor (GLP-1R) agonist exendin-4 (Ex-4) protects the BBB and reduces brain inflammation from cerebral ischemia, and GLP-1R is expressed on astrocytes. However, the effect of Ex-4 on astrocytes in subjects with AIS remains unclear. METHODS: In the present study, we investigated the effect of Ex-4 on astrocytes cultured under oxygen-glucose deprivation (OGD) plus reoxygenation conditions and determined whether the effect influences bEnd.3 cells. We used various methods, including permeability assays, western blotting, immunofluorescence staining, and gelatin zymography, in vitro and in vivo. RESULTS: Ex-4 reduced OGD-induced astrocyte-derived vascular endothelial growth factor (VEGF-A), matrix metalloproteinase-9 (MMP-9), chemokine monocyte chemoattractant protein-1 (MCP-1), and chemokine C-X-C motif ligand 1 (CXCL-1). The reduction in astrocyte-derived VEGF-A and MMP-9 was related to the increased expression of tight junction proteins (TJPs) in bEnd.3 cells. Ex-4 improved neurologic deficit scores, reduced the infarct area, and ameliorated BBB breakdown as well as decreased astrocyte-derived VEGF-A, MMP-9, CXCL-1, and MCP-1 levels in ischemic brain tissues from rats subjected to middle cerebral artery occlusion. Ex-4 reduced the activation of the JAK2/STAT3 signaling pathway in astrocytes following OGD. CONCLUSION: Based on these findings, ischemia-induced inflammation and BBB breakdown can be improved by Ex-4 through an astrocyte-dependent manner.


Assuntos
Astrócitos/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Exenatida/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Infarto da Artéria Cerebral Média/metabolismo , Inflamação/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Animais , Astrócitos/metabolismo , Barreira Hematoencefálica/patologia , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/metabolismo , Exenatida/uso terapêutico , Infarto da Artéria Cerebral Média/patologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Curr Neurovasc Res ; 16(4): 340-347, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31549956

RESUMO

BACKGROUND AND OBJECTIVE: Vitamin D deficiency is internationally recognized among the potentially modifiable risk factors for ischemic cardio-cerebrovascular diseases. However, the association between vitamin D deficiency and stroke morbidity or mortality remains insufficiently known. Our aim is to investigate their relevance to 25-hydroxyvitamin D [25(OH) D] levels and clinical severity and outcome after 3 months in first-ever ischemic stroke. METHODS: Retrospective analysis of 356 consecutive patients in first-ever ischemic stroke between 2013 and 2015. Serum 25(OH) D levels were measured at baseline. Stroke severity was assessed at admission using the National Institutes of Health Stroke Scale (NIHSS) score. Functional outcome after 3 months of onset was evaluated using the modified Rankin scale (mRS). RESULTS: Among the 356 enrolled patients, HbA1c was higher in insufficiency/deficiency group than that in the sufficiency group (6.3 ± 1.7 vs. 5.9 ± 1.1, p =0.015). The hospital stay was longer in insufficiency/deficiency group than that in the sufficiency group (11 (8-17) vs. 9.5 (7-13), p = 0.035). There was a significant inversed trend between serum 25(OH) D levels and hospital stay (OR 0.960, P = 0.031), using logistic regression. CONCLUSION: 25(OH)D levels are associated with glucose homeostasis, 25(OH) D contributes to increase the length of hospital stay. Low serum 25-OHD level is an independent predictor for hospital stay in first-ever ischemic stroke. Vitamin D deficiency did not predict functional outcome in the span of 3 months.


Assuntos
Glicemia/metabolismo , Isquemia Encefálica/complicações , Homeostase/fisiologia , Acidente Vascular Cerebral/complicações , Vitamina D/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Vitamina D/sangue , Deficiência de Vitamina D/sangue
15.
BMC Neurol ; 19(1): 94, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072329

RESUMO

BACKGROUND: Recurrent optic neuritis (ON) was previously thought to be associated with multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD). Meningoencephalitis has recently been suggested to be a clinical finding typical of myelin oligodendrocyte glycoprotein (MOG) encephalomyelitis. We report a Chinese patient with recurrent ON at disease initiation, who had a delayed diagnosis of MOG-IgG syndrome, until recurrent meningoencephalitis appeared and serum MOG-IgG was detected. CASE PRESENTATION: From the age of 7 years, an AQP4-IgG negative female patient had 10 disease recurrences, including 4 episodes of recurrent ON, 4 episodes of fever and meningoencephalitis, and 2 episodes of ON as well as meningoencephalitis. She was initially diagnosed as recurrent ON and treated with glucocorticoids followed by gradual tapering when ON reoccurred. Later, she was diagnosed as central nervous system infection when fever and meningoencephalitis appeared, and antiviral drugs and glucocorticoids were used. However, when she returned to our department for follow-up on July 2017, the results of serum demyelinating autoimmune antibody revealed positive MOG-IgG (titer 1:320 by an in-house, cell-based assay using live cells transfected with full-length human MOG). A diagnosis of MOG-IgG syndrome was established. CONCLUSIONS: Testing for MOG-IgG in atypical MS and NMOSD patients, and patients with meningoencephalitis with a history of relapsing demyelinating symptoms is warranted.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/diagnóstico , Meningoencefalite/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Neurite Óptica/imunologia , Autoanticorpos/sangue , Autoantígenos/imunologia , Criança , Diagnóstico Tardio , Feminino , Humanos , Imunoglobulina G , Recidiva , Síndrome
16.
ISME J ; 13(8): 2044-2057, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962514

RESUMO

Several abundant but yet uncultivated bacterial groups exist in extreme iron- and sulfur-rich environments, and the physiology, biodiversity, and ecological roles of these bacteria remain a mystery. Here we retrieved four metagenome-assembled genomes (MAGs) from an artificial acid mine drainage (AMD) system, and propose they belong to a new deltaproteobacterial order, Candidatus Acidulodesulfobacterales. The distribution pattern of Ca. Acidulodesulfobacterales in AMDs across Southeast China correlated strongly with ferrous iron. Reconstructed metabolic pathways and gene expression profiles showed that they were likely facultatively anaerobic autotrophs capable of nitrogen fixation. In addition to dissimilatory sulfate reduction, encoded by dsrAB, dsrD, dsrL, and dsrEFH genes, these microorganisms might also oxidize sulfide, depending on oxygen concentration and/or oxidation reduction potential. Several genes with homology to those involved in iron metabolism were also identified, suggesting their potential role in iron cycling. In addition, the expression of abundant resistance genes revealed the mechanisms of adaptation and response to the extreme environmental stresses endured by these organisms in the AMD environment. These findings shed light on the distribution, diversity, and potential ecological role of the new order Ca. Acidulodesulfobacterales in nature.


Assuntos
Biodiversidade , Deltaproteobacteria/genética , Metagenoma/genética , Enxofre/química , Transcriptoma , Adaptação Fisiológica , China , Deltaproteobacteria/fisiologia , Ecologia , Perfilação da Expressão Gênica , Ferro/metabolismo , Metagenômica , Mineração , Fixação de Nitrogênio , Oxirredução , Oxigênio/metabolismo , Estresse Fisiológico , Sulfetos/química
17.
Chemistry ; 25(33): 7779-7797, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30985033

RESUMO

With the ultimate goal of simultaneously finding cost-effective, more earth-abundant, and high-performance alternatives to commercial Pt/Pd-based catalysts for electrocatalysis, this review article highlights advances in the use of perovskite metal oxides as both catalysts and catalyst supports towards the oxygen reduction reaction (ORR) and the methanol oxidation reaction (MOR) within a direct methanol fuel cell (DMFC) configuration. Specifically, perovskite metal oxides are promising as versatile functional replacements for conventional platinum-group metals, in part because of their excellent ionic conductivity, overall resistance to corrosion, good proton-transport properties, and potential for interesting acidic surface chemistry, all of which contribute to their high activity and reasonable stability, especially within an alkaline electrolytic environment.

18.
FASEB J ; 33(3): 4376-4387, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30694693

RESUMO

Astrocytes mediate the destruction of the blood-brain barrier (BBB) during ischemic stroke (IS). IL-9 is a pleiotropic cytokine that we previously found to be highly expressed in peripheral blood mononuclear cells from patients with IS, and the presence of IL-9 receptors on astrocytes has been reported in the literature. Here, we detected the effect of IL-9 on astrocytes using an anti-IL-9-neutralizing antibody to treat rats with experimental stroke. Supernatants from astrocytes treated with or without oxygen-glucose deprivation and/or IL-9 were incubated with bEnd.3 cell monolayers after blocking the IL-9 receptor on the endothelium. Immunofluorescence staining and Western blot analyses were conducted to observe the change in tight junction proteins (TJPs) in bEnd.3 cells as well as the level of VEGF-A and possible signal pathways in astrocytes. We also applied middle cerebral artery occlusion (MCAO) models to determine the effect of anti-IL-9-neutralizing antibodies on IS. As a result, astrocyte-conditioned medium treated with IL-9 aggravated the disruption of the BBB accomplished by the degradation of TJPs in endothelial cells. In addition, IL-9 increased the level of VEGF-A in astrocytes, and blocking the effect of VEGF-A reversed the breakdown of the BBB. In the MCAO model, anti-IL-9-neutralizing antibody reduced the infarct volume and BBB destruction. Mechanistically, the anti-IL-9-neutralizing antibody repaired the damaged TJPs (zonula occludens 1, occludin, and claudin-5) and induced a decrease in VEGF-A expression in ischemic lateral brain tissue. In contrast, a local injection of recombinant murine IL-9 to the brain resulted in a marked up-regulation of VEGF-A in the striatum. In conclusion, anti-IL-9-neutralizing antibody can reduce the severity of IS partially by alleviating the destruction of the BBB via down-regulation of astrocyte-derived VEGF-A. This finding suggests that targeting IL-9 or VEGF-A could provide a new direction for the treatment of IS.-Tan, S., Shan, Y., Lin, Y., Liao, S., Zhang, B., Zeng, Q., Wang, Y., Deng, Z., Chen, C., Hu, X., Peng, L., Qiu, W., Lu, Z. Neutralization of IL-9 ameliorates experimental stroke by repairing the blood-brain barrier via down-regulation of astrocyte-derived vascular endothelial growth factor-A.


Assuntos
Astrócitos/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Interleucina-9/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Astrócitos/metabolismo , Hipóxia Celular , Células Cultivadas , Corpo Estriado/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Glucose/farmacologia , Hipóxia-Isquemia Encefálica , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Inflamação , Interleucina-9/administração & dosagem , Interleucina-9/imunologia , Interleucina-9/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas de Junções Íntimas/metabolismo , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética
19.
Front Neurol ; 9: 657, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30294295

RESUMO

Purpose: Perforating Artery Infarcts (PAIs) can be divided into two subtypes based on their etiologies: branch Atheromatous Disease (BAD) and Lacunar Infarct (LI). Recent studies have shown that while both subtypes can be caused by large artery lesions, the different mechanisms that underlie their development are not clear. This study was designed to use High-Resolution Magnetic Resonance Imaging (HRMRI) to explore the differences that contribute to the occurrence of these two subtypes in large artery lesions in the anterior circulation. Methods: Fifty patients with an acute PAI in the anterior circulation were enrolled (32 BAD and 18 LI patients). The ipsilateral middle cerebral artery (MCA) was scanned with HRMRI to analyze the atherosclerosis plaques. Artery remodeling and plaque characteristics of MCA lesions were compared between the two subtypes. Results: The rate of MCA lesions was significantly higher in BAD and substantially lower in LI (P = 0.033). LAs for the lumen areas in Bad, they were smaller than LI (P < 0.001), Additionally, the plaque area (P = 0.001) and plaque burden (P < 0.001) were superior in the BAD group. Most BAD patients displayed non-positive remodeling, while the great majority of LI patients showed positive remodeling (P < 0.001). Conclusion: In the anterior circulation, a considerable amount of BAD and LI share similarities with atherosclerotic plaques in large arteries. BAD patients mainly showed relatively large and stable atherosclerotic plaques in large arteries, while LI patients mainly exhibited relatively small and unstable atherosclerotic plaques. Clinical Trial Registration: This clinical trial is a retrospective study and therefore does not require registration.

20.
Medicine (Baltimore) ; 97(38): e12470, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30235742

RESUMO

This research was aimed to explore correlation of gene polymorphisms of CD36 and ApoE with susceptibility of Alzheimer disease (AD).This study was a case-control study. Two hundred eleven AD hospitalized patients were selected as the AD group and 241 subjects were selected as the control group. PCR-RFLP was used to detect three loci (rs7755, rs3211956, and rs10499859) of CD36 gene and ApoE genotype. Chi-square test and univariate nonconditional logistic regression analysis were used to calculate the odds ratio (OR) and 95% confidence interval (95% CI). The haplotypes were constructed using SHEsis online software and the correlation between haplotypes and AD was analyzed. Meanwhile, differences of 3 alleles of ApoE and 6 genotypes (E2/E2, E2/E3, E2/E4, E3/E3, E3/E4, E4/E4) were compared between AD and control groups.The frequencies of rs7755 genotype (χ = 10.780, P = .005) and allele (χ = 10.549, P = .001) were statistically different between 2 groups. The genotype frequency of rs3211956 was statistically different between AD and control groups (χ = 10.119, P = .006). For the rs7755 locus, GG genotype (OR: 2.013, 95% CI: 1.098-3.699) was an independent risk factor for AD compared with AA genotype. In the dominant model, the risk to develop AD in AG/GG genotype was 1.686 times higher than AA genotype. For the rs3211956 locus, compared with TT genotype, GT genotype (OR: 0.536, 95% CI: 0.340-0.846) was a protective factor for AD after adjusting various physiological and biochemical factors. In the dominant model, the risk of GT/GG genotype to develop AD was reduced by 41.6%. For ApoE gene, the distribution differences of E2/E3 (χ = 9.216, P = .002), E3/E4 (χ = 7.728, P = .005), and E4/E4 had statistical significance between the 2 groups. The frequencies of allele E2 (χ = 9.359, P = .002) and E4 (χ = 13.995, P < .001) were statistically significant between AD and control groups.The rs7755 and rs3211956 loci polymorphisms of CD36 gene and genotype E2/E3, E3/E4, E4/E4 of ApoE gene, and E2 and E4 alleles were statistically related with AD.


Assuntos
Doença de Alzheimer/genética , Apolipoproteínas E/genética , Antígenos CD36/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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