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1.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36077390

RESUMEN

Mutations in the CFTR chloride channel result in intestinal obstructive episodes in cystic fibrosis (CF) patients and in CF animal models. In this study, we explored the possibility of reducing the frequency of obstructive episodes in cftr-/- mice through the oral application of a gut-selective NHE3 inhibitor tenapanor and searched for the underlying mechanisms involved. Sex- and age-matched cftr+/+ and cftr-/- mice were orally gavaged twice daily with 30 mg kg-1 tenapanor or vehicle for a period of 21 days. Body weight and stool water content was assessed daily and gastrointestinal transit time (GTT) once weekly. The mice were sacrificed when an intestinal obstruction was suspected or after 21 days, and stool and tissues were collected for further analysis. Twenty-one day tenapanor application resulted in a significant increase in stool water content and stool alkalinity and a significant decrease in GTT in cftr+/+ and cftr-/- mice. Tenapanor significantly reduced obstructive episodes to 8% compared to 46% in vehicle-treated cftr-/- mice and prevented mucosal inflammation. A decrease in cryptal hyperproliferation, mucus accumulation, and mucosal mast cell number was also observed in tenapanor- compared to vehicle-treated, unobstructed cftr-/- mice. Overall, oral tenapanor application prevented obstructive episodes in CFTR-deficient mice and was safe in cftr+/+ and cftr-/- mice. These results suggest that tenapanor may be a safe and affordable adjunctive therapy in cystic fibrosis patients to alleviate constipation and prevent recurrent DIOS.


Asunto(s)
Fibrosis Quística , Obstrucción Intestinal , Animales , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Isoquinolinas , Ratones , Ratones Endogámicos CFTR , Intercambiador 3 de Sodio-Hidrógeno , Sulfonamidas , Agua
2.
J Child Psychol Psychiatry ; 62(10): 1246-1254, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33738808

RESUMEN

BACKGROUND: Symptom improvement in children with tic disorder (TD) following fecal microbiota transplantation led us to investigate the gut microbiota in TD. This exploratory study aims to depict the gut microbial profile in patients with TD and explore the impact of dopamine receptor antagonist (DRA) drugs on the composition and metabolic function of the gut microbiota. METHODS: The gut microbiota were profiled in fecal samples of 49 children with TD and 50 matched healthy controls (HC) using shotgun metagenomic sequencing. A random forest (RF) model was constructed using the gut bacterial species to distinguish TD from HC. Associations between clinical metadata and microbial abundance or function were analyzed using MaAsLin2 and Spearman correlation. RESULTS: The gut microbiota in children with TD was featured by higher abundances of Bacteroides plebeius and Ruminococcus lactaris (a potential pro-inflammatory taxon) and lower abundances of Prevotella stercorea and Streptococcus lutetiensis compared to HC. The constructed RF model accurately distinguished TD from HC based on the gut microbiota profile, resulting in an AUC of 0.884. Significant correlations were observed between tic symptom severity and the abundances of multiple bacterial species and gut microbiota metabolic functions. Multivariate analysis identified an upregulation of 4-aminobutanoate (GABA) degradation in the gut microbiota associated with TD status. The gut microbiota of DRA-treated TD children showed a distinct gut microbiota compared to the treatment-naïve group, represented by an increase in some potential enteric pathogens such as Escherichia coli, a decline in several species including Akkermansia muciniphila, and alterations in various metabolic functions. CONCLUSIONS: Bacterial species promoting inflammatory responses and those modulating neurotransmitters such as GABA may be involved in the pathogenesis of TD. The use of DRA drugs is likely to induce overgrowth of some enteric pathogens and alter the gut microbiota metabolism.


Asunto(s)
Microbioma Gastrointestinal , Trastornos de Tic , Bacteroides , Niño , Humanos , Prevotella , Ruminococcus , Streptococcus
3.
J Neuroinflammation ; 15(1): 92, 2018 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-29566716

RESUMEN

BACKGROUND: Zinc-α2-glycoprotein (ZAG) is a 42-kDa protein reported as an anti-inflammatory adipocytokine. Evidences from clinical and experimental studies revealed that brain inflammation plays important roles in epileptogenesis and seizure. Interestingly, closely relationship between ZAG and many important inflammatory mediators has been proven. Our previous study identified ZAG in neurons and found that ZAG is decreased in epilepsy and interacts with TGFß and ERK. This study aimed to investigate the role of ZAG in seizure and explore its effect on seizure-related neuroinflammation. METHODS: We overexpressed AZGP1 in the hippocampus of rats via adeno-associated virus vector injection and observed their seizure behavior and EEG after pentylenetetrazol (PTZ) kindling. The level of typical inflammation mediators including TNFα, IL-6, TGFß, ERK, and ERK phosphorylation were determined. RESULTS: The overexpression of AZGP1 reduced the seizure severity, prolonged the latency of kindling, and alleviated epileptiform discharges in EEG changes induced by PTZ. Overexpression of AZGP1 also suppressed the expression of TNFα, IL-6, TGFß, and ERK phosphorylaton in PTZ-kindled rats. CONCLUSIONS: ZAG may inhibit TGFß-mediated ERK phosphorylation and inhibit neuroinflammation mediated by TNFα and IL-6, suggesting ZAG may suppress seizure via inhibiting neuroinflammation. ZAG may be a potential and novel therapeutic target for epilepsy.


Asunto(s)
Proteínas Portadoras/metabolismo , Encefalitis , Regulación de la Expresión Génica/genética , Glicoproteínas/metabolismo , Convulsiones/complicaciones , Convulsiones/terapia , Adipoquinas , Animales , Ondas Encefálicas/efectos de los fármacos , Ondas Encefálicas/fisiología , Proteínas Portadoras/genética , Convulsivantes/toxicidad , Citocinas/metabolismo , Modelos Animales de Enfermedad , Electroencefalografía , Encefalitis/etiología , Encefalitis/metabolismo , Encefalitis/terapia , Glicoproteínas/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Hipocampo , Excitación Neurológica/efectos de los fármacos , Masculino , Pentilenotetrazol/toxicidad , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Convulsiones/patología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factores de Tiempo , Transducción Genética , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismo
4.
Proc Natl Acad Sci U S A ; 110(9): 3543-8, 2013 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-23401502

RESUMEN

A therapeutic goal in the treatment of certain CNS diseases, including multiple sclerosis, amyotrophic lateral sclerosis, and Parkinson disease, is to down-regulate inflammatory pathways. Inflammatory molecules produced by microglia are responsible for removal of damaged neurons, but can cause collateral damage to normal neurons located close to defective neurons. Although estrogen can inactivate microglia and inhibit the recruitment of T cells and macrophages into the CNS, there is controversy regarding which of the two estrogen receptors (ERs), ERα or ERß, mediates the beneficial effects in microglia. In this study, we found that ERß, but not ERα, is expressed in microglia. Using the experimental autoimmune encephalomyelitis (EAE) model in SJL/J mice, we evaluated the benefit of an ERß agonist as a modulator of neuroinflammation. Treatment of EAE mice with LY3201, a selective ERß agonist provided by Eli Lilly, resulted in marked reduction of activated microglia in the spinal cord. LY3201 down-regulated the nuclear transcription factor NF-κB, as well as the NF-κB-induced gene inducible nitric oxide synthase in microglia and CD3(+) T cells. In addition, LY3201 inhibited T-cell reactivity through regulation of indoleamine-2,3-dioxygenase. In the EAE model, treatment with LY3201 decreased mortality in the first 2 wk after disease onset, and also reduced the severity of symptoms in mice surviving for 4 wk. Our data show that ERß-selective agonists, by modulating the immune system in both microglia and T cells, offer promise as a useful class of drugs for treating degenerative diseases of the CNS.


Asunto(s)
Benzopiranos/uso terapéutico , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/inmunología , Receptor beta de Estrógeno/metabolismo , Microglía/metabolismo , Terapia Molecular Dirigida , Linfocitos T/metabolismo , Animales , Benzopiranos/farmacología , Regulación hacia Abajo/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/enzimología , Encefalomielitis Autoinmune Experimental/patología , Receptor alfa de Estrógeno/metabolismo , Femenino , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Ratones , Microglía/efectos de los fármacos , Microglía/patología , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Médula Espinal/efectos de los fármacos , Médula Espinal/enzimología , Médula Espinal/patología , Linfocitos T/efectos de los fármacos , Linfocitos T/patología
5.
Proc Natl Acad Sci U S A ; 109(32): 13112-7, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22826221

RESUMEN

Parkinson disease (PD) is a progressive neurodegenerative disease whose progression may be slowed, but at present there is no pharmacological intervention that would stop or reverse the disease. Liver X receptor ß (LXRß) is a member of the nuclear receptor super gene family expressed in the central nervous system, where it is important for cortical layering during development and survival of dopaminergic neurons throughout life. In the present study we have used the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD to investigate the possible use of LXRß as a target for prevention or treatment of PD. The dopaminergic neurons of the substantia nigra of LXRß(-/-) mice were much more severely affected by MPTP than were those of their WT littermates. In addition, the number of activated microglia and GFAP-positive astrocytes was higher in the substantia nigra of LXRß(-/-) mice than in WT littermates. Administration of the LXR agonist GW3965 to MPTP-treated WT mice protected against loss of dopaminergic neurons and of dopaminergic fibers projecting to the striatum, and resulted in fewer activated microglia and astroglia. Surprisingly, LXRß was not expressed in the neurons of the substantia nigra but in the microglia and astroglia. We conclude that LXR agonists may have beneficial effects in treatment of PD by modulating the cytotoxic functions of microglia.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Receptores Nucleares Huérfanos/metabolismo , Trastornos Parkinsonianos/metabolismo , Sustancia Negra/citología , Análisis de Varianza , Animales , Astrocitos/metabolismo , Benzoatos/farmacología , Bencilaminas/farmacología , Proteína Ácida Fibrilar de la Glía , Inmunohistoquímica , Receptores X del Hígado , Masculino , Ratones , Ratones Noqueados , Microglía/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptores Nucleares Huérfanos/antagonistas & inhibidores , Receptores Nucleares Huérfanos/genética , Trastornos Parkinsonianos/prevención & control , Trastornos Parkinsonianos/terapia
6.
Proc Natl Acad Sci U S A ; 109(19): 7493-8, 2012 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-22529354

RESUMEN

Anxiety disorders are the most prevalent mental disorders in adolescents in the United States. Female adolescents are more likely than males to be affected with anxiety disorders, but less likely to have behavioral and substance abuse disorders. The prefrontal cortex (PFC), amygdala, and dorsal raphe are known to be involved in anxiety disorders. Inhibitory input from the PFC to the amygdala controls fear and anxiety typically originating in the amygdala, and disruption of the inhibitory input from the PFC leads to anxiety, fear, and personality changes. Recent studies have implicated liver X receptor ß (LXRß) in key neurodevelopmental processes and neurodegenerative diseases. In the present study, we used elevated plus-maze, startle and prepulse inhibition, open field, and novel object recognition tests to evaluate behavior in female LXRß KO (LXRß(-/-)) mice. We found that the female LXRß(-/-) mice were anxious with impaired behavioral responses but normal locomotion and memory. Immunohistochemistry analysis revealed decreased expression of the enzyme responsible for GABA synthesis, glutamic acid decarboxylase (65+67), in the ventromedial PFC. Expression of tryptophan hydroxylase 2 in the dorsal raphe was normal. We conclude that the anxiogenic phenotype in female LXRß(-/-) mice is caused by reduced GABAergic input from the ventromedial PFC to the amygdala.


Asunto(s)
Ansiedad/psicología , Glutamato Descarboxilasa/metabolismo , Receptores Nucleares Huérfanos/deficiencia , Corteza Prefrontal/enzimología , Adolescente , Animales , Ansiedad/fisiopatología , Miedo/fisiología , Miedo/psicología , Femenino , Humanos , Inmunohistoquímica , Receptores X del Hígado , Masculino , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Ratones , Ratones Noqueados , Actividad Motora/fisiología , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/fisiología , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiopatología , Factores Sexuales , Ácido gamma-Aminobutírico/biosíntesis
7.
Proc Natl Acad Sci U S A ; 109(5): 1708-12, 2012 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-22307635

RESUMEN

An estrogen receptor (ER) ß ligand (LY3201) with a preference for ERß over ERα was administered in s.c. pellets releasing 0.04 mg/d. The brains of these mice were examined 3 d after treatment had begun. Although estradiol-17ß is known to increase spine density and glutaminergic signaling, as measured by Golgi staining, a clear reduction in spines was evident on the dendritic branches in LY3201-treated mice but no morphological alteration and no difference in the number of dendritic spines on dendritic stems were observed. In the LY3201-treatment group, there was higher expression of glutamic acid decarboxylase (GAD) in layer V of cortex and in the CA1 of hippocampus, more GAD(+) terminals surrounding the pyramidal neurons and less glutamate receptor (NMDAR) on the neurons in layer V. There were no alterations in expression of Iba1 or in Olig2 or CNPase. However, GFAP(+) astrocytes were increased in the LY3201-treatment group. There were also more projections characteristic of activated astrocytes and increased expression of glutamine synthetase (GS). No expression of ERß was detectable in the nuclei of astrocytes. Clearly, LY3201 caused a shift in the balance between excitatory and inhibitory neurotransmission in favor of inhibition. This shift was due in part to increased synthesis of GABA and increased removal of glutamate from the synaptic cleft by astrocytes. The data reveal that treatment with a selective ERß agonist results in changes opposite to those reported in estradiol-17ß-treated mice and suggests that ERα and ERß play opposing roles in the brain.


Asunto(s)
Benzopiranos/farmacología , Encéfalo/efectos de los fármacos , Espinas Dendríticas/efectos de los fármacos , Receptor beta de Estrógeno/efectos de los fármacos , Transducción de Señal , Ácido gamma-Aminobutírico/metabolismo , Animales , Encéfalo/metabolismo , Espinas Dendríticas/metabolismo , Receptor beta de Estrógeno/metabolismo , Ligandos , Ratones , Receptores de N-Metil-D-Aspartato/metabolismo
8.
DNA Cell Biol ; 43(3): 125-131, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38350140

RESUMEN

Cornus iridoid glycosides (CIGs), including loganin and morroniside, are the main active components of Cornus officinalis. As one of the key enzymes in the biosynthesis of CIGs, geranyl pyrophosphate synthase (GPPS) catalyzes the formation of geranyl pyrophosphate, which is the direct precursor of CIGs. In this study, the C. officinalis geranyl pyrophosphate synthase (CoGPPS) sequence was cloned from C. officinalis and analyzed. The cDNA sequence of the CoGPPS gene was 915 bp (GenBank No. OR725699). Phylogenetic analysis showed that CoGPPS was closely related to the GPPS sequence of Actinidia chinensis and Camellia sinensis, but relatively distantly related to Paeonia lactiflora and Tripterygium wilfordii. Results from the quantitative real-time PCR showed the spatiotemporal expression pattern of CoGPPS; that is, CoGPPS was specifically expressed in the fruits. Subcellular localization assay proved that CoGPPS was specifically found in chloroplasts. Loganin and morroniside contents in the tissues were detected by high-performance liquid chromatography, and both compounds were found to be at higher levels in the fruits than in leaves. Thus, this study laid the foundation for further studies on the synthetic pathway of CIGs.


Asunto(s)
Cornus , Iridoides , Fosfatos de Poliisoprenilo , Cornus/genética , Cornus/química , Filogenia , Glicósidos Iridoides , Clonación Molecular
9.
Chemosphere ; 352: 141364, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38336034

RESUMEN

Diverse paths generated by reactive oxygen species (ROS) can mediate contaminant transformation and fate in the soil/aquatic environments. However, the pathways for ROS production upon the oxygenation of redox-active ferrous iron minerals are underappreciated. Ferrihydrite (Fh) can be reduced to produce Fe(II) by Shewanella oneidensis MR-1, a representative strain of dissimilatory iron-reducing bacteria (DIRB). The microbial reaction formed a spent Fh product named mr-Fh that contained Fe(II). Material properties of mr-Fh were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Magnetite could be observed in all mr-Fh samples produced over 1-day incubation, which might greatly favor the Fe(II) oxygenation process to produce hydroxyl radical (•OH). The maximum amount of dissolved Fe(II) can reach 1.1 mM derived from added 1 g/L Fh together with glucose as a carbon source, much higher than the 0.5 mM generated in the case of the Luria-Bertani carbon source. This may confirm that MR-1 can effectively reduce Fh and produce biogenetic Fe(II). Furthermore, the oxygenation of Fe(II) on the mr-Fh surface can produce abundant ROS, wherein the maximum cumulative •OH content is raised to about 120 µM within 48 h at pH 5, but it is decreased to about 100 µM at pH 7 for the case of MR-1/Fh system after a 7-day incubation. Thus, MR-1-mediated Fh reduction is a critical link to enhance ROS production, and the •OH species is among them the predominant form. XPS analysis proves that a conservable amount of Fe(II) species is subject to adsorption onto mr-Fh. Here, MR-1-mediated ROS production is highly dependent on the redox activity of the form Fe(II), which should be the counterpart presented as the adsorbed Fe(II) on surfaces. Hence, our study provides new insights into understanding the mechanisms that can significantly govern ROS generation in the redox-oscillation environment.


Asunto(s)
Compuestos Férricos , Shewanella , Especies Reactivas de Oxígeno/metabolismo , Compuestos Férricos/química , Minerales/química , Hierro/química , Oxidación-Reducción , Shewanella/metabolismo , Óxido Ferrosoférrico/metabolismo , Carbono/metabolismo
10.
Proc Natl Acad Sci U S A ; 107(27): 12305-10, 2010 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-20566868

RESUMEN

In the past year, two members of the nuclear receptor family, liver X receptor beta (LXRbeta) and thyroid hormone receptor alpha (TRalpha), have been found to be essential for correct migration of neurons in the developing cortex in mouse embryos. TRalpha and LXRbeta bind to identical response elements on DNA and sometimes regulate the same genes. The reason for the migration defect in the LXRbeta(-/-) mouse and the possibility that TRalpha may be involved are the subjects of the present study. At E15.5, expression of reelin and VLDLR was similar but expression of apolipoprotein E receptor 2 (ApoER2) (the reelin receptor) was much lower in LXRbeta(-/-) than in WT mice. Knockout of ApoER2 is known to lead to abnormal cortical lamination. Surprisingly, by postnatal day 14 (P14), no morphological abnormalities were detectable in the cortex of LXRbeta(-/-) mice and ApoER2 expression was much stronger than in WT controls. Thus, a postnatal mechanism leads to increase in ApoER2 expression by P14. TRalpha also regulates ApoER2. In both WT and LXRbeta(-/-) mice, expression of TRalpha was high at postnatal day 2. By P14 it was reduced to low levels in WT mice but was still abundantly expressed in the cortex of LXRbeta(-/-) mice. Based on the present data we hypothesize that reduction in the level of ApoER2 is the reason for the retarded migration of later-born neurons in LXRbeta(-/-) mice but that as thyroid hormone (TH) increases after birth the neurons do find their correct place in the cortex.


Asunto(s)
Química Encefálica , Corteza Cerebral/metabolismo , Receptores Nucleares Huérfanos/metabolismo , Receptores alfa de Hormona Tiroidea/metabolismo , Animales , Animales Recién Nacidos , Movimiento Celular , Corteza Cerebral/embriología , Corteza Cerebral/crecimiento & desarrollo , Inmunohistoquímica , Proteínas Relacionadas con Receptor de LDL , Receptores X del Hígado , Ratones , Ratones Noqueados , Neuronas/citología , Neuronas/metabolismo , Receptores Nucleares Huérfanos/genética , Receptores de Lipoproteína/metabolismo , Proteína Reelina , Receptores alfa de Hormona Tiroidea/genética , Factores de Tiempo
11.
Plants (Basel) ; 12(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37836156

RESUMEN

Forsythia suspensa is a deciduous shrub that belongs to the family Myrtaceae, and its dried fruits are used as medicine. F. suspensa contains several secondary metabolites, which exert pharmacological effects. One of the main active components is forsythin, which exhibits free radical scavenging, antioxidant, anti-inflammatory, and anti-cancer effects. Mitogen-activated protein kinase (MAPKs) can increase the activity of WRKY family transcription factors in a phosphorylated manner, thereby increasing the content of secondary metabolites. However, the mechanism of interaction between MAPKs and WRKYs in F. suspensa remains unclear. In this study, we cloned the genes of FsWRKY4 and FsMAPK3, and performed a bioinformatics analysis. The expression patterns of FsWRKY4 and FsMAPK3 were analyzed in the different developmental stages of leaf and fruit from F. suspensa using real-time fluorescence quantitative PCR (qRT-PCR). Subcellular localization analysis of FsWRKY4 and FsMAPK3 proteins was performed using a laser scanning confocal microscope. The existence of interactions between FsWRKY4 and FsMPAK3 in vitro was verified by yeast two-hybridization. Results showed that the cDNA of FsWRKY4 (GenBank number: OR566682) and FsMAPK3 (GenBank number: OR566683) were 1587 and 522 bp, respectively. The expression of FsWRKY4 was higher in the leaves than in fruits, and the expression of FsMAPK3 was higher in fruits but lower in leaves. The subcellular localization results indicated that FsWRKY4 was localized in the nucleus and FsMAPK3 in the cytoplasm and nucleus. The prey vector pGADT7-FsWRKY4 and bait vector pGBKT7-FsMAPK3 were constructed and co-transferred into Y2H Glod yeast receptor cells. The results indicated that FsWRKY4 and FsMAPK3 proteins interact with each other in vitro. The preliminary study may provide a basis for more precise elucidation of the synthesis of secondary metabolites in F. suspensa.

12.
J Phys Chem Lett ; 14(17): 3995-4003, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37083499

RESUMEN

Understanding precipitation formation at lanthanum hydroxide (La(OH)3) nanoparticle-solution interfaces plays a crucial role in catalysis, adsorption, and electrochemical energy storage applications. Liquid-phase transmission electron microscopy enables powerful visualization with high resolution. However, direct atomic-scale imaging of the interfacial metal (hydro)oxide nanostructure in solutions has been a major challenge due to their beam-driven dissolution. Combining focused ion beam and aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, we present an atomic-scale study of precipitation formation at La(OH)3 nanoparticle interfaces after reaction with phosphate. The structure transformation is observed to occur at high- and low-crystalline La(OH)3 nanoparticle surfaces. Low-crystalline La(OH)3 mostly transformed and high-crystalline ones partly converted to LaPO4 precipitations on the outer surface. The long-term structure evolution shows the low transformation of high-crystalline La(OH)3 nanoparticles to LaPO4 precipitation. Because precipitation at solid-solution interfaces is common in nature and industry, these results could provide valuable references for their atomic-scale observation.

13.
NPJ Parkinsons Dis ; 8(1): 82, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35750692

RESUMEN

Tremor is one of the core symptoms of Parkinson's disease (PD), but its mechanism is poorly understood. The cerebellum is a growing focus in PD-related researches and is reported to play an important role in tremor in PD. The cerebellum may participate in the modulation of tremor amplitude via cerebello-thalamo-cortical circuits. The cerebellar excitatory projections to the ventral intermediate nucleus of the thalamus may be enhanced due to PD-related changes, including dopaminergic/non-dopaminergic system abnormality, white matter damage, and deep nuclei impairment, which may contribute to dysregulation and resistance to levodopa of tremor. This review summarized the pathological, structural, and functional changes of the cerebellum in PD and discussed the role of the cerebellum in PD-related tremor, aiming to provide an overview of the cerebellum-related mechanism of tremor in PD.

14.
Front Genet ; 12: 739344, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34603397

RESUMEN

N6-methyladenosine (m6A) is one of the most prevalent RNA modifications in mRNA and non-coding RNA. In this study, we identified 10 upregulated m6A regulators at both mRNA and protein levels, and 2,479 m6A-related lncRNAs. Moreover, the m6A-related long noncoding RNAs (lncRNAs) could clearly stratify the colon adenocarcinoma (COAD) samples into three subtypes. The subtype 2 had nearly 40% of samples with microsatellite instability (MSI), significantly higher than the two other subtypes. In accordance with this finding, the inflammatory response-related pathways were highly activated in this subtype. The subtype-3 had a shorter overall survival and a higher proportion of patients with advanced stage than subtypes 1 and 2 (p-value < 0.05). Pathway analysis suggested that the energy metabolism-related pathways might be aberrantly activated in subtype 3. In addition, we observed that most of the m6A readers and m6A-related lncRNAs were upregulated in subtype 3, suggesting that the m6A readers and the m6A-related lncRNAs might be associated with metabolic reprogramming and unfavorable outcome in COAD. Among the m6A-related lncRNAs in subtype 3, four were predicted as prognostically relevant. Functional inference suggested that CTD-3184A7.4, RP11-458F8.4, and RP11-108L7.15 were positively correlated with the energy metabolism-related pathways, further suggesting that these lncRNAs might be involved in energy metabolism-related pathways. In summary, we conducted a systematic data analysis to identify the key m6A regulators and m6A-related lncRNAs, and evaluated their clinical and functional importance in COAD, which may provide important evidences for further m6A-related researches.

15.
Br J Pharmacol ; 178(5): 1018-1036, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33179259

RESUMEN

BACKGROUND AND PURPOSE: Constipation and intestinal obstructive episodes are major health problems in cystic fibrosis (CF) patients. Three FDA-approved drugs against constipation-prone irritable bowel syndrome were tested for their ability to increase luminal fluidity and alkalinity in cystic fibrosis transmembrane conductance regulator (CFTR) null (cftr-/- ) and F508del mutant (F508delmut/mut ) murine intestine. EXPERIMENTAL APPROACH: Guanylate cyclase C agonist linaclotide, PGE1 analogue lubiprostone and intestine-specific NHE3 inhibitor tenapanor were perfused through a ~3 cm jejunal, proximal or mid-distal colonic segment in anaesthetized cftr-/- , F508delmut/mut and WT mice. Net fluid balance was determined gravimetrically and alkaline output by pH-stat back titration. KEY RESULTS: Basal jejunal fluid absorptive rates were significantly higher and basal HCO3- output was significantly lower in cftr-/- and F508delmut/mut compared to WT mice. In cftr-/- and F508delmut/mut mice, all three drugs significantly inhibited the fluid absorptive rate and increased alkaline output in the jejunum and tenapanor and lubiprostone, but not linaclotide, in the colon. After tenapanor pre-incubation, linaclotide elicited a robust fluid secretory response in WT jejunum, while no further change in absorptive rates was observed in cftr-/- and F508delmut/mut jejunum, suggesting that the increase in gut fluidity and alkalinity by linaclotide in CF gut is mediated via NHE3 inhibition. Lubiprostone also inhibited fluid absorption in cftr-/- and F508delmut/mut jejunum via NHE3 inhibition but had a residual NHE3-independent effect. CONCLUSION AND IMPLICATIONS: Linaclotide, lubiprostone and tenapanor reduced fluid absorption and increased alkaline output in the CF gut. Their application may ameliorate constipation and reduce obstructive episodes in CF patients.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística , Mucosa Intestinal , Animales , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Transporte Iónico , Ratones , Isoformas de Proteínas/metabolismo , Intercambiador 3 de Sodio-Hidrógeno/metabolismo
16.
Nanomaterials (Basel) ; 10(1)2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31963244

RESUMEN

Composite polymer electrolytes provide an emerging solution for new battery development by replacing liquid electrolytes, which are commonly complexes of polyethylene oxide (PEO) with ceramic fillers. However, the agglomeration of fillers and weak interaction restrict their conductivities. By contrast with the prevailing methods of blending preformed ceramic fillers within the polymer matrix, here we proposed an in situ synthesis method of SiO2 nanoparticles in the PEO matrix. In this case, robust chemical interactions between SiO2 nanoparticles, lithium salt and PEO chains were induced by the in situ non-hydrolytic sol gel process. The in situ synthesized nanocomposite polymer electrolyte delivered an impressive ionic conductivity of ~1.1 × 10-4 S cm-1 at 30 °C, which is two orders of magnitude higher than that of the preformed synthesized composite polymer electrolyte. In addition, an extended electrochemical window of up to 5 V vs. Li/Li+ was achieved. The Li/nanocomposite polymer electrolyte/Li symmetric cell demonstrated a stable long-term cycling performance of over 700 h at 0.01-0.1 mA cm-2 without short circuiting. The all-solid-state battery consisting of the nanocomposite polymer electrolyte, Li metal and LiFePO4 provides a discharge capacity of 123.5 mAh g-1, a Coulombic efficiency above 99% and a good capacity retention of 70% after 100 cycles.

17.
Acta Physiol (Oxf) ; 230(2): e13498, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32415725

RESUMEN

AIM: SLC26A3 (DRA) mediates the absorption of luminal Cl- in exchange for HCO3- in the distal intestine. Its expression is lost in congenital chloride diarrhoea (CLD) and strongly decreased in the presence of intestinal inflammation. To characterize the consequences of a loss of Slc26a3 beyond disturbed electrolyte transport, colonic mucus synthesis, surface accumulation and composition, pH microclimate, microbiome composition and development of inflammation was studied in slc26a3-/- mice. METHODS: The epithelial surface pH microclimate and the surface mucus accumulation in vivo was assessed by two photon microscopy in exteriorized mid colon of anaesthetized slc26a3-/- and wt littermates. Mucus synthesis, composition and inflammatory markers were studied by qPCR and immunohistochemistry and microbiome composition by 16S rRNA sequencing. RESULTS: Colonic pH microclimate was significantly more acidic in slc26a3-/- and to a lesser extent in cftr-/- than in wt mice. Goblet cell thecae per crypt were decreased in slc26a3-/- and increased in cftr-/- colon. Mucus accumulation in vivo was reduced, but much less so than in cftr-/- colon, which is possibly related to the different colonic fluid balance. Slc26a3-/- colonic luminal microbiome displayed strong decrease in diversity. These alterations preceded and maybe causally related to increased mucosal TNFα mRNA expression levels and leucocyte infiltration in the mid-distal colon of slc26a3-/- but not of cftr-/- mice. CONCLUSIONS: These findings may explain the strong increase in the susceptibility of slc26a3-/- mice to DSS damage, and offer insight into the mechanisms leading to an increased incidence of intestinal inflammation in CLD patients.


Asunto(s)
Antiportadores , Microbiota , Animales , Antiportadores de Cloruro-Bicarbonato , Colon , Humanos , Concentración de Iones de Hidrógeno , Mucosa Intestinal , Ratones , Microclima , Mucinas , ARN Ribosómico 16S , Transportadores de Sulfato/genética
18.
Am J Transl Res ; 11(7): 4411-4424, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31396345

RESUMEN

Multiple sclerosis (MS) is an autoimmune, demyelinating, and neurodegenerative disease of the central nervous system (CNS) that affects 2-2.5 million people worldwide. Although the etiology of MS is not well known, MS is widely considered to be an autoimmune disease. Currently approved MS drugs reduce relapse rates but fail to reverse or prevent neurodegeneration and disability progression. Increasing evidence indicates that microglia and major histocompatibility complex class II (MHC II) expression in these cells play important roles in the pathophysiology of MS. For a T cell to contribute to CNS pathogenesis, it must be reactivated by antigen-presenting cells within the CNS parenchyma. Susceptibility to MS is associated with MHC II genes, suggesting that presentation of antigens on MHC II plays an important role in CD4+ T-cell reactivation and disease initiation. An ERß-selective agonist was previously reported to suppress reactivation of T cells invading the spinal cord, thereby reducing the severity of symptoms and decreasing mortality in the first 2 weeks after disease onset. However, the mechanism by which the expression of MHC II in microglia is regulated by ERß-selective agonists is still unclear. Therefore, we hypothesize that ERß-selective agonists inhibit MHC II expression in microglia via inhibition of class II trans-activator (CIITA) expression by a mechanism involving inhibition of the translocation of IFNγ regulatory factor (IRF-1) to the nucleus, thereby inhibiting the inflammatory response and symptoms in the MS model.

19.
J Neurol Sci ; 384: 133-138, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29153510

RESUMEN

BACKGROUND: Clinical disagreement over antiplatelet (AP) resumption in patients with primary intracranial hemorrhage (ICH) has long existed. This meta-analysis aimed to evaluate the benefits of AP resumption on preventing ischemic or thromboembolic events against its risks of promoting ICH recurrence or hematoma expansion. METHODS: All relevant articles published in Pubmed, EMBASE, the Cochrane Library, and Science Direct from January 1950 to March 2017 were sourced, and the combined relative risk (RR) was calculated. RESULTS: A total of 3648 articles were found, and after screening, 6 cohort studies including 1916 patients were included in this meta-analysis. AP resumption was associated with a decreased risk of ischemic or thromboembolic events (RR, 0.61; 95% confidence interval (CI), 0.48-0.79; P<0.01). There was no significant difference in the risk of ICH recurrence or hematoma expansion between patients with or without AP resumption (RR, 0.84; 95% CI, 0.47-1.51; P=0.56). CONCLUSION: AP resumption in patients with primary ICH reduced the risk of ischemic or thromboembolic events, without significant increase of risk of ICH recurrence or hematoma expansion.


Asunto(s)
Hemorragias Intracraneales/epidemiología , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Isquemia Encefálica/epidemiología , Isquemia Encefálica/prevención & control , Humanos , Hemorragias Intracraneales/complicaciones , Riesgo , Tromboembolia/epidemiología , Tromboembolia/prevención & control
20.
J Am Heart Assoc ; 6(7)2017 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-28743788

RESUMEN

BACKGROUND: Inconsistent findings have been obtained for previous studies evaluating the association between antihypertensive medication (AHM) adherence and the risk of stroke. This dose-response meta-analysis was designed to investigate the association between AHM adherence and stroke risk. METHODS AND RESULTS: MEDLINE and Embase databases were systematically searched to identify relevant studies. The quantification of adherence to AHM was calculated as the percentage of the sum of days with AHM actually taken divided by the total number of days in a specific period. Summary relative risks (RR) and 95% CIs were estimated using a random-effects model. Stratified and dose-response analyses were also performed. A total of 18 studies with 1 356 188 participants were included. The summary RR of stroke for the highest compared with the lowest AHM adherence level was 0.73 (95% CI, 0.67-0.79). Stratified by stroke subtype, a higher AHM adherence was associated with lower risks of ischemic stroke (RR, 0.74; 95% CI, 0.69-0.79) and hemorrhagic stroke (RR, 0.55; 95% CI, 0.42-0.72). Moreover, both fatal (RR, 0.51; 95% CI, 0.36-0.73) and nonfatal stroke (RR, 0.52; 95% CI, 0.28-0.94) were lower in participants with higher AHM adherence. The results of a dose-response analysis indicated that a 20% increment in AHM adherence level was associated with a 9% lower risk of stroke (RR, 0.91; 95% CI, 0.86-0.96). CONCLUSIONS: Higher AHM adherence is dose-dependently associated with a lower risk of stroke in patients with hypertension.


Asunto(s)
Antihipertensivos/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Isquemia Encefálica/prevención & control , Hipertensión/tratamiento farmacológico , Hemorragia Intracraneal Hipertensiva/prevención & control , Cumplimiento de la Medicación , Accidente Cerebrovascular/prevención & control , Anciano , Isquemia Encefálica/etiología , Isquemia Encefálica/fisiopatología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/fisiopatología , Hemorragia Intracraneal Hipertensiva/etiología , Hemorragia Intracraneal Hipertensiva/fisiopatología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
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