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1.
Colloids Surf B Biointerfaces ; 238: 113913, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608463

RESUMO

A gout attack could be viewed as a nucleation event. Many reports have shown that the typical molecular structure of crystallization inhibitors usually contains carboxyl and hydroxyl groups, which could interact with solute molecules through hydrogen bonding, thereby suppressing the nucleation and growth of crystals. Since 1923, l-lactic acid (LA), a molecule with structural features of inhibitors, has been speculated to be a trigger for acute gout because metabolized LA temporarily reduces uric acid excretion and leads to a slow increase in serum uric acid concentration. However, many cases of gout presumably triggered by elevated lactate in a very short period of 4 h are often inexplicable. Here, we present the unexpected result that LA has a significant "opposite effect" on the nucleation and growth of gouty pathological crystals, which is that as the concentration of the additive LA increases, the nucleation and growth of the crystals is suppressed and then facilitated. This approach may help our clarifying the long-standing "misunderstandings" and further understanding the association between metabolized LA and increased risk of gout attacks. Finally, a novel mechanism called "tailed-made occupancy (TMO)" was used to explain the nucleation and crystallization effects of LA on sodium urate monohydrate (MSUM).


Assuntos
Cristalização , Gota , Ácido Láctico , Ácido Úrico , Gota/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo , Humanos , Ácido Úrico/química , Ácido Úrico/metabolismo
2.
Colloids Surf B Biointerfaces ; 236: 113803, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367289

RESUMO

The core to the treatment of gout is the elimination of pathologic crystal, monosodium urate monohydrate (MSUM). The primary treatment available is to gradually dissolve the "culprit crystals" by lowering the blood uric acid concentration with medications, which often takes a long time and in severe cases must still be treated surgically. Herein, we developed a dynamic bionic platform based on a hydrogel composite membrane (HCM) to screen the direct facilitated solubilization of MSUM crystals by small organic molecules in bionic saturated, or even supersaturated, solutions. The customized and biologically safe (NAGA/PEGDA/NIPAM) HCM, which is consistent with the main amino acid composition of articular cartilage, well mimics the entire process of organic molecules leading to the dissolution of MSUM crystals in the joint system. With the verifications of this platform, it is shown that l-aspartic acid (ASP) significantly promotes the dissolution of MSUM crystals not only in saturated but also in supersaturated solutions. Furthermore, a novel mechanism called "crane effect" was used to explain this "dissolution effect" of ASP on MSUM, which stems from the ability of ASP to lock onto the surface of MSUM crystals through hydrogen bonding by virtue of its two carboxyl groups, and simultaneously its amino group lifts the uric acid molecules from the surface of MSUM crystals by virtue of interactions of hydrogen bonding. The results of bulk crystallization, scanning electron microscopy (SEM), powder X-diffraction (PXRD), and density-functional theory (DFT) studies are quantitatively consistent with this hypothetical "crane effect" mechanism. Hence, this HCM-based functional platform could provide entirely novel ideas and methods for drug design and screening for the treatment of pathological crystal diseases of gout.


Assuntos
Gota , Ácido Úrico , Humanos , Ácido Úrico/química , Biônica , Gota/tratamento farmacológico , Gota/metabolismo , Cristalização , Hidrogéis
3.
Funct Plant Biol ; 512024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38326230

RESUMO

Phytohormones play a key role in regulating tiller number. Ascorbic acid (Asc)-phytohormone interaction plays a pivotal role in the regulation of senescence. We analysed the relationship between Asc and the enzyme concentrations and gene transcript abundances related to the signal perception of strigolactones (SLs), the contents of four phytohormones (abscisic acid, ABA; jasmonic acid, JA; indole acetic acid, IAA; cytokinin, CTK), the enzyme concentrations and gene transcript abundances related to the synthesis or transportation of these four phytohormones. Our results showed that Asc deficiency leads to the upregulation of enzyme concentrations, gene transcript abundances related to the SL signal perception, ABA synthesis and IAA transport. The altered level of Asc also leads to a change in the contents of ABA, JA, IAA and CTK. These findings support the conclusion that Asc or Asc/DHA play an important role in the signal perception and transduction of SLs, and Asc may affect the coordinated regulation of SL, IAA and CTK on rice (Oryza sativa ) tillering.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Lactonas , Oryza , Reguladores de Crescimento de Plantas , Ácido Ascórbico , Percepção
4.
Sci Rep ; 12(1): 20205, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418371

RESUMO

With continuous population growth and farmland decrease, the food security is seriously threatened. Farmland reclamation has been used as a means of raising the agricultural productivity and improving the ecological environment. However, the lack of reclaimed soil represents a serious problem. To verify the feasibility and effect of using large amounts of iron tailings to construct farmland, ten treatments (T1-T10) were designed to represent different soil profiles of regional normal farmland and constructed profiles using iron tailings. All treatments involving an iron tailings layer below topsoil exhibited higher soil water contents. The field capacity under T3 (20-cm iron tailings layer below cinnamon soil (b)) was 19.20% higher than that under T7 (20-cm red clay layer below cinnamon soil (b)), and the field capacity under T5 (20-cm iron tailings layer below cinnamon soil (a)) was 2.26% higher than that under T9 (20-cm red clay layer below cinnamon soil (a)). The soil water contents under T3 and T5 were almost the same as those under T7 and T9, respectively. The water-holding capacity of the 30-cm iron tailings layer (T6) was better than that of the 20-cm iron tailings layer (T2). Additionally, none of the treatments caused salt injury to maize. The maize height and stem thickness under the treatments employing iron tailings layers below topsoil were significantly greater than those in normal farmland; the maize height and stem thickness under T3 were 136.82% and 32.02% greater, respectively, than those under T7, and the values under T5 were 9.13% and 9.56% greater, respectively, than those under T9. The maize yields matched or even surpassed those in normal farmland, namely, the maize yield under T5 was equal to that under T9, and the maize yield under T3 was 12.69% higher than that under T7. In general, the application of an iron tailings layer below topsoil to construct farmland is a feasible and environmentally friendly way to realize sustainable farmland utilization and is beneficial to soil quality and crop yield improvement. Collectively, these results provide insight into the efficient utilization of iron tailings and environmental protection.


Assuntos
Ferro , Solo , Fazendas , Argila , Zea mays , Água
5.
RSC Adv ; 12(35): 22574-22580, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36106008

RESUMO

The first gout attack in a hyperuricaemic patient may be regarded as a nucleation event which is caused by monosodium urate monohydrate (MSUM) deposition in the synovial fluid. The effect of Tailor-Made Inhibition (TMI) may be effective as drugs for the prevention of aberrant nucleation and crystallization. Therefore, the understanding of the underlying mechanisms in inhibiting the MSUM nucleation by TMI has proven to be of great significance. Yet most of the published studies about nucleation inhibition have tended to focus on simpler molecular models with a hydrogen-bonded acceptor and donor, which may be not suitable for the uric acid molecule with multiple hydrogen-bonded acceptors and donors under physiological conditions. Herein, the mechanisms of nucleation inhibition of MSUM were explored in a simulated biological environment (0.15 M Na+ and pH 7.40) in the presence and absence of TMI. And the evidence of nucleation inhibition by TMI in solution and the amorphous form of MSUM was investigated by HNMR, IR, Raman, PXRD, Dynamic light scattering (DLS), induction time measurements, and density functional theory (DFT) calculations. Results showed that the inhibition comes from a combination of kinetic and thermodynamic effects, with an impact of kinetics as the TMI inhibition effects far exceeded what could be accounted for by changes in usual factors of classical nucleation theory. The data demonstrated that the complex between urate and TMI disturbed the formation of two-dimensional sheets of sodion and purine rings parallel to the (011) plane and further impeded the formation of a three-dimensional structure with aromatic stacking interactions in solution. To our knowledge, the nucleation inhibition of TMI is achieved by suppressing interplanar stacking, which is a mechanism proposed for the first time.

6.
Org Lett ; 22(20): 8127-8131, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33026812

RESUMO

We developed an approach for direct selective hydroxylation of heterobenzylic methylenes to secondary alcohols avoiding overoxidation to ketones by using a KOBu-t/DMSO/air system. Most reactions could reach completion in several minutes to give hydroxylated products in 41-76% yields. Using DMSO-d6, this protocol resulted in difunctionalization of heterobenzylic methylenes to afford α-deuterated secondary alcohols (>93% incorporation). By employing this method, active pharmaceutical ingredients carbinoxamine and doxylamine were synthesized in two steps in moderate yields.

7.
J Plant Physiol ; 246-247: 153139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32114415

RESUMO

Rice tillering, which determines the panicle number per plant, is an important agronomic trait for grain production. In higher plants, ascorbic acid (Asc) plays a major role in ROS-scavenging activity. l-Galactono-1, 4-lactone dehydrogenase (GalLDH, EC1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in plants. Previously, we have reported that homozygous L-GalLDH-suppressed transgenic rice plants (GI) display a reduced tiller number and a lower level of foliar carotenoids (Car) compared with wild type. Strigolactones (SL), which play an important role in the suppression of shoot branching, are synthesized in the roots of rice plant using Car as substrates. In this paper, the relationship between Asc, SL, the accumulation of H2O2, changes in antioxidant capacity, enzyme activities, and gene transcriptions related to the synthesis of SL were analyzed in transgenic rice plants for L-GalLDH suppressed (GI-1 and GI-2) and overexpressing (GO-2). The results showed that the altered level of Asc in the L-GalLDH transgenic rice plants leads to a change in redox homeostasis, resulting in a marked accumulation of H2O2 and decreased antioxidant capacity in GI-1 and GI-2, but lower H2O2 content and increased antioxidant capacity in GO-2. Meanwhile, the altered level of Asc also leads to altered enzyme activities and gene transcript abundances related to SL synthesis in L-GalLDH transgenics. These observations support the conclusion that Asc influences tiller number in the L-GalLDH transgenics by affecting H2O2 accumulation and antioxidant capacity, and altering those enzyme activities and gene transcript abundances related to SL synthesis.


Assuntos
Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica de Plantas , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Oryza/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Oryza/enzimologia , Oryza/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
8.
Somatosens Mot Res ; 37(1): 45-49, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32000557

RESUMO

Objective: To investigate the clinical features and imaging characteristics of mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS).Methods: Seventeen patients with MELAS diagnosed in the Affiliated Hospital of Xuzhou Medical University from July 2014 to August 2018 were enrolled in this study and their clinical manifestations, imaging and histopathological features were retrospectively analysed. We also discussed and summarised the related literature.Results: All of the 12 patients had seizures; stroke-like episodes in 12 cases; audio-visual impairment in 12 cases; headache in six cases; dysplasia in four cases; mental retardation in three cases; ataxia in two cases. On cranial magnetic resonance (MR) scans, the most common manifestations were in temporal-occipital-parietal lobe, cortical or subcortical areas as well as frontal lobe, thalamus, and basal ganglia showing long or equal T1 signals, long T2 signals, and hyperintense or iso-intense diffusion-weighted imaging (DWI) signals accompanied by ventricular enlargement and brain atrophy. MR spectroscopy showed that lactic acid peaks could be found in lesion sites, normal brain tissues, and cerebrospinal fluid. Muscle biopsy and genetic testing are the gold standard for diagnosing MELAS, muscle biopsy revealed COX-negative muscle fibres and SDH-stained red ragged fibres (RRF) under the sarcolemma. Mutations of mtDNA A3243G locus were common on gene testing. Improvement of mitochondrial function was observed after symptomatic and supportive treatment.Conclusion: MELAS should be considered for patients with epileptic seizures, headache, stroke-like episodes, extraocular palsy, cognitive decline and other clinical manifestations with the lesion located in the temporal-occipital-parietal lobe regardless of the distribution of blood vessels, and further examinations including muscle biopsy and gene testing should be performed to confirm the diagnosis.


Assuntos
Síndrome MELAS/diagnóstico , Síndrome MELAS/patologia , Síndrome MELAS/fisiopatologia , Adolescente , Adulto , Atrofia/patologia , Criança , Feminino , Testes Genéticos , Humanos , Síndrome MELAS/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Langmuir ; 36(8): 2136-2142, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32027142

RESUMO

Biomineralization is characterized by the fact that the crystallization of inorganic minerals is guided by an in vivo biological interface. However, the interfaces that direct calcification are widely debated up to date. In this paper, it was found that the two-dimensional (2D) immiscible domain of cholesterol in the lipid bilayer can induce the deposition of calcium phosphate by rapidly promoting the nucleation of the hydroxyapatite (001) plane. This promotion effect is related to the high lattice matching degree between the 2D cholesterol immiscible domain and the (001) plane of hydroxyapatite (HAP), which leads to the heteroepitaxy of HAP. The lipid bilayer derived from cells or vesicles is the largest biological interface in the body, thus revealing whether the lipid bilayer can induce the deposition of calcium phosphate will facilitate the understanding of the important role of cells or vesicles in calcification.

10.
Funct Plant Biol ; 47(3): 263-278, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32029065

RESUMO

Leaf senescence is an important factor that affects crop yield traits and is regulated by various factors. Here, we propose the photo-carbon imbalance hypothesis to explain the mechanism of rice leaf senescence. The main idea of this hypothesis is that carbon assimilation decreases faster than the absorption of light energy in photosynthesis during the late stages of rice growth, which ultimately results in leaf senescence. Our results indicate that endogenous ascorbic acid (Asc) plays an important role in leaf senescence by affecting the expression of senescence genes, thereby influencing photosynthetic capacity and consequently grain yield. The effects of exogenous Asc and methyl jasmonate (MeJA) on photosynthetic capability implied that the balance between photoreaction and carbon assimilation is regulated by exogenous antioxidants or accelerators of senescence. The results of the shading treatments indicated that shading will mitigate the photo-carbon imbalance and improve photosynthetic capacity, resulting in increased yields. Increasing antioxidant concentrations can enhance the reactive oxygen species (ROS) scavenging capacity, whereas shading reduces excess light energy, which may help to restore the photo-carbon balance.


Assuntos
Oryza , Ácido Ascórbico , Carbono , Fotossíntese , Folhas de Planta
11.
Front Neurol ; 10: 1107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708855

RESUMO

Objective: To investigate the anatomical characteristics, clinical manifestations, and imaging features of bilateral cerebral peduncular infarction. Methods: A retrospective analysis was performed on 11 patients diagnosed with bilateral cerebral peduncular infarction in the Affiliated Hospital of Xuzhou Medical University from December 2014 to December 2018. Their clinical and imaging features were analyzed and summarized in combination with the relevant national and international literature. Results: Among all the patients, there were eight cases with a history of hypertension, four cases with a history of diabetes mellitus, and four cases with a history of smoking. Conscious disturbance was observed in nine cases, quadriplegia in seven cases, pseudobulbar paralysis in three cases, and ataxia in one case. Brain magnetic resonance (MR) scans of bilateral cerebral peduncles showed patchy abnormal shadows with a hypointense signal on T1-weighted imaging (T1WI) and apparent diffusion coefficient (ADC) and hyperintense signal on T2-weighted imaging (T2WI), fluid-attenuated inversion recovery (FLAIR), and diffusion-weighted imaging (DWI). Computed tomography angiography (CTA) scans of head and neck showed severe stenosis or occlusion of vertebral artery, basilar artery, or posterior cerebral artery. All the patients received standardized treatment for cerebral infarction. Six patients died while five were left disabled. Conclusion: Bilateral cerebral peduncle infarction may be related to cerebral perfusion insufficiency caused by the stenosis or occlusion of vertebrobasilar artery and its branches. The main clinical manifestations are locked-in syndrome and persistent vegetative state. The specific imaging feature of "Mickey Mouse ear"-like infarction is associated with a poor prognosis.

12.
Org Lett ; 21(4): 904-907, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30698446

RESUMO

A copper-promoted intramolecular C-H oxidative amination reaction between secondary amine (N-H) and C(sp3)-H at the benzylic position of azaarenes or α-position of ketones for the synthesis of aziridine derivatives has been developed. Moreover, a practical annulation of electron-deficient vinylarenes with an unprotected primary alkyl amine by a Yb(OTf)3-CuI relay system has also been reported. The reactions were carried out with oxygen as the sole oxidant to give the N-alkyl- and N-arylaziridines in good yields.

13.
Neurol Sci ; 40(2): 269-274, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30377845

RESUMO

OBJECTIVE: To explore the clinical and imaging features of patients with hypertrophic cranial pachymeningitis (HCP). METHODS: A retrospective study was performed on 22 patients with HCP diagnosed at the Affiliated Hospital of Xuzhou Medical University from February 2014 to September 2017. RESULTS: A headache was present as an initial symptom in 18 patients. The headache was associated with the loss of vision (2 cases), facial pain (1 case), and unsteady walking (1 case). Other symptoms included cranial nerve dysfunction (15 cases), cerebellar ataxia (4 cases), and sinus thrombosis (3 cases). In the laboratory tests, 7 patients showed an increased number of white blood cells, higher levels of C-reaction protein (CRP), and erythrocyte sedimentation rate (ESR). An elevated level of immunoglobulin G4 (IgG4) and the presence of the anti-neutrophil cytoplasmic antibody (ANCA) were found in 3 and 2 patients respectively. There were 17 patients who had abnormalities in their cerebrospinal fluid (CSF) on lumbar puncture. On magnetic resonance imaging (MRI), a local or generalized thickening was observed in the cerebral falx, the tentorium of the cerebellum, the fronto-parietal lobe, the occipito-parietal lobe, and the dura of skull base. A dural biopsy obtained in one case showed a variety of inflammatory changes. An immunohistochemical analysis revealed the positivity of CD138, IgG, and IgG4 in some cells. All 22 patients had a good response to corticosteroids. CONCLUSION: HCP mainly leads to a headache and the paralysis of multiple cranial nerves. A biopsy and MRI are often required and serve as the basis for the diagnosis and effective therapy.


Assuntos
Meningite/diagnóstico por imagem , Meningite/fisiopatologia , Adolescente , Corticosteroides/uso terapêutico , Adulto , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Diagnóstico Diferencial , Dura-Máter/diagnóstico por imagem , Dura-Máter/patologia , Feminino , Cefaleia/diagnóstico por imagem , Cefaleia/tratamento farmacológico , Cefaleia/patologia , Cefaleia/fisiopatologia , Humanos , Hipertrofia/diagnóstico por imagem , Hipertrofia/tratamento farmacológico , Hipertrofia/patologia , Hipertrofia/fisiopatologia , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Meningite/tratamento farmacológico , Meningite/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
14.
Org Lett ; 20(5): 1304-1307, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29450999

RESUMO

Herein, 2-vinylpyridines as a new type of electron-poor system for the asymmetric cross Rauhut-Currier reaction are reported. 2-Vinylpyridines are chemo- and enantioselectively activated by a newly designed chiral phosphine catalyst. The new reaction provides a powerful synthetic tool for accessing structurally diverse, highly valued chiral pyridine building blocks in good yields and with high enantioselectivities. Preliminary mechanistic studies reveal that two NH protons in the catalyst are critical for the synergistic activation of the substrates and governing the stereoselectivity of this reaction.

15.
Neurosci Lett ; 654: 70-79, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28642149

RESUMO

Activated Metabotropic glutamate receptors 5(mGluR5) exhibits protective effects against ischemic brain damage, but the underlying mechanisms are not clearly known. Brain-derived neurotrophic factor (BDNF), as a valuable member of neurotrophic factor family, exerts its protection by combining with its high-affinity receptor tyrosine protein kinase B (TrkB). To investigate the role of activated mGluR5 against oxygen-glucose deprivation (OGD)/reoxygenation (R)-mediated cytotoxicity, the cell viability, apoptosis, the release of inflammatory cytokines and accumulation of reactive oxygen species (ROS) were evaluated in BV2 cells (Microglia cell line) with or without OGD/R exposure. Our data show that CHPG (the selective mGluR5 agonist) pretreatment, as an mGluR5 agonist, protected BV2 cells against OGD/R-induced cytotoxicity, apoptosis, the release of inflammatory cytokines, and the accumulation of ROS. However, these effects were significantly reversed by the mGluR5 antagonist MPEP pretreatment. Our data also show that the expressions of BDNF and TrkB were significantly decreased in BV2 cells with OGD/R exposure. CHPG pretreatment significantly enhanced the expressions of BDNF and TrkB in BV2 cells with OGD/R exposure. However, the increased expressions were significantly abrogated by MPEP pretreatment. In addition, inhibition of BDNF/TrKB pathway by K252a also attenuated the protective effects of activated mGluR5 against OGD/R-induced cytotoxicity, apoptosis and the release of inflammatory cytokines. Morever, pretreatment with exogenous BDNF protected BV2 cells against OGD/R induced apoptosis and release of inflammatory cytokines. These data suggested that BDNF/TrKB pathway may be involved in regulating activated mGluR5' protective effects against OGD/R induced cytotoxicity in BV2 cells.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Receptor trkB/metabolismo , Animais , Linhagem Celular , Camundongos , Transdução de Sinais/fisiologia
16.
J Plant Physiol ; 211: 13-26, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28142093

RESUMO

The grain chalkiness of rice (Oryza sativa L.), which determines the rice quality and price, is a major concern in rice breeding. Reactive oxygen species (ROS) plays a critical role in regulating rice endosperm chalkiness. Ascorbic acid (Asc) is a major plant antioxidant, which strictly regulates the levels of ROS. l-galactono-1, 4-lactone dehydrogenase (L-GalLDH, EC 1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in higher plants. Here we show that the L-GalLDH-suppressed transgenic rice, GI-1 and GI-2, which have constitutively low (between 30% and 50%) leaf and grain Asc content compared with the wild-type (WT), exhibit significantly increased grain chalkiness. Further examination showed that the deficiency of Asc resulted in a higher lipid peroxidation and H2O2 content, accompanied by a lower hydroxyl radical scavenging rate, total antioxidant capacity and photosynthetic ability. In addition, changes of the enzyme activities and gene transcript abundances related to starch synthesis were also observed in GI-1 and GI-2 grains. The results we presented here suggest a close correlation between Asc deficiency and grain chalkiness in the L-GalLDH-suppressed transgenics. Asc deficiency leads to the accumulation of H2O2, affecting antioxidant capacity and photosynthetic function, changing enzyme activities and gene transcript abundances related to starch synthesis, finally leading to the increased grain chalkiness.


Assuntos
Ácido Ascórbico/metabolismo , Grão Comestível/metabolismo , Oryza/enzimologia , Oryza/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Sequestradores de Radicais Livres/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Oryza/metabolismo , Fenótipo , Fotossíntese , Folhas de Planta/enzimologia , Folhas de Planta/genética , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Amido/metabolismo
17.
Immunol Res ; 64(5-6): 1216-1224, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27677768

RESUMO

T cell immunoglobulin mucin domain-1(Tim-1) was recently identified to be critical and essential for optimal regulatory B cells function in maintaining immune tolerance. We aimed to measure the expression levels of Tim-1 on B cells from patients with Myasthenia Gravis (MG) and to investigate whether the expression of Tim-1 is associated with pathogenesis of MG. A total of 34 patients with MG (18 generalized MG (GMG) and 16 ocular MG (OMG) and 24 healthy donors were recruited in this study. The quantitative myasthenia gravis score (QMGS) was used to evaluate the clinical severity. Real-time PCR and flow cytometry were used to measure the levels of Tim-1 expressed on peripheral B cells. Peripheral CD138+ plasma cells were assayed by flow cytometry. Serum Th17-related cytokines (IL-6, IL-1ß and IL-17) and anti-AChR antibody (Ab) titers were tested by enzyme-linked immunosorbent assay (ELISA). Our data demonstrated that the mRNA and protein expression levels of B cell Tim-1 in both the GMG and OMG groups were significantly lower than those in healthy controls, with lower expression in GMG than in OMG. Tim-1 expression on B cells from OMG/GMG was negatively correlated with clinical severity, plasma cells frequency, serum Th17-related cytokines and anti-AChR Ab levels. Our results indicated that aberrant expression of Tim-1 exists on B cells and may contribute to the Th17 polarization and antibody-secreting plasma cells differentiation in MG patients.


Assuntos
Antígenos CD19/metabolismo , Linfócitos B/imunologia , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Miastenia Gravis/imunologia , Células Th17/imunologia , Adulto , Anticorpos/metabolismo , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Colinérgicos/imunologia
18.
Clin Exp Med ; 16(3): 413-21, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25962782

RESUMO

miR-181c is a newly identified negative regulator of immune cell activation. In this study, we aimed to investigate the expression and functional role of miR-181c in myasthenia gravis (MG). miR-181c showed significant downregulation in peripheral blood mononuclear cells (PBMCs) from MG patients compared with healthy controls, with lower expression in generalized patients than in ocular ones. MG patients also had increased serum IL-7 and IL-17 levels. Additionally, serum IL-7 level presents a positive correlation with the serum IL-17 level. miR-181c levels were negatively correlated with serum levels of IL-7 and IL-17 in either generalized patients or ocular patients. A luciferase reporter assay revealed that miR-181c could directly bind to the 3'-UTR of interleukin-7. Forced expression of miR-181c led to decreased IL-7 and IL-17 release in cultured PBMCs, while depletion of miR-181c increased the secretion of these two proinflammatory cytokines. The results from our study suggested for the first time that miR-181c was able to negatively regulate the production of proinflammatory cytokines IL-7 and IL-17 in MG patients, and it is a novel potential therapeutic target for MG.


Assuntos
Interleucina-17/sangue , Interleucina-7/sangue , Leucócitos Mononucleares/química , MicroRNAs/análise , Miastenia Gravis/patologia , Soro/química , Adulto , Idoso , Regulação para Baixo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Neuroimmune Pharmacol ; 10(4): 635-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26500105

RESUMO

Th17-related cytokines have been suggested to play a crucial role in myasthenia gravis (MG) pathogenesis.The tumor necrosis factor (TNF)-α-induced protein 8-like-2 (TNFAIP8L2 or TIPE2), is a newly identified member of the tumor necrosis TNFAIP8 family which is an essential negative regulator of both innate and adaptive immunity. In the present study, the expression of TIPE2 mRNA and protein in peripheral blood mononuclear cells (PBMC) from healthy and MG subjects were detected by Real-time PCR and Western blotting.The serum IL-6, IL-17 and IL-21 levels were tested by ELISA. Furthermore, PBMC from MG patients were purified and stimulated with LPS (TLR4 agonist) with or without transfection of TIPE2 expressing adenovirus, then the expression of TIPE2 and Th17-specific transcriptional factor RORγt and the IL-6, IL-17 and IL-21 levels of supernatant were analized. Our data demonstrated that the expression of TIPE2 mRNA and protein was reduced in MG compared with normal controls, with lower expression in generalized patients than in ocular ones. Furthermore, TIPE2 mRNA presents a significantly negative correlation with the serum levels of IL-6, IL-17 and IL-21 in either generalized patients or ocular patients. In cultured MG PBMC, TLR4 activation led to the down-regulation of TIPE2, while the expression of RORγt and production of IL-6, IL-17 and IL-21 were significantly increased. However, when TIPE2 was overexpressed, these TLR4 activation-induced effects were significantly abrogated. Overall, our results indicated for the first time that TIPE2 may participate in the development of MG through negatively regulation of TLR4-mediated autoimmune T helper 17 cell responses.


Assuntos
Autoimunidade/imunologia , Interleucinas/sangue , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucócitos Mononucleares/imunologia , Miastenia Gravis/sangue , Células Th17/imunologia , Receptor 4 Toll-Like/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/imunologia
20.
Brain Res ; 1624: 489-496, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26279113

RESUMO

Stem cell-based treatments have been reported to be a potential strategy for stroke. However, tumorigenic potential and low survival rates of transplanted cells could attenuate the efficacy of the stem cell-based treatments. The application of stem cell-condition medium (CM) may be a practicable approach to conquer these limitations. In this study, we investigated whether intranasal administration of human umbilical cord mesenchymal stem cells (hUCMSCs)-CM has the therapeutic effects in rats after stroke. Adult male rats were subjected to middle cerebral artery occlusion (MCAo) and were treated by intranasal routine with or without hUCMSCs-CM (1 ml/kg/d), starting 24h after MCAo and daily for 14 days. Neurological functional tests, blood brain barrier (BBB) leakage, were measured. Angiogenesis and angiogenic factor expression were measured by immunohistochemistry, and Western blot, respectively. hUCMSCs-CM treatment of stroke by intranasal routine starting 24h after MCAo in rats significantly enhances BBB functional integrity and promotes functional outcome but does not decrease lesion volume compared to rats in DMEM/F12 medium control group and saline control group. Treatment of ischemic rats with hUCMSCs-CM by intranasal routine also significantly decreases the levels of Ang2 and increases the levels of both Ang1 and Tie2 in the ischemic brain. To take together, increased expression of Ang1 and Tie2 and decreased expression of Ang2, induced by hUCMSCs-CM treatment, contribute to vascular remodeling in the ischemic brain which plays an important role in functional outcome after stroke.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Sangue Fetal/citologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Células-Tronco Mesenquimais/metabolismo , Remodelação Vascular/efeitos dos fármacos , Administração Intranasal , Análise de Variância , Animais , Células Cultivadas , Desmina/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Infarto da Artéria Cerebral Média/patologia , Masculino , Células-Tronco Mesenquimais/química , Exame Neurológico , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Fator de von Willebrand/metabolismo
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