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1.
Angew Chem Int Ed Engl ; 63(19): e202401091, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38489249

RESUMEN

Ligand coupling on hypervalent main group elements has emerged as a pivotal methodology for the synthesis of functionalized N-heteroaromatic compounds in recent years due to the avoidance of transition metals and the mildness of the reaction conditions. In this direction, the reaction of N-heteroaryl sulfur(IV) and N-heteroaryl phosphorus(V) compounds has been well studied. However, the ligand coupling of sulfur(VI) is still underdeveloped and the reaction of alkyl N-heteroarylsulfones is still elusive, which does not match the high status of sulfones as the chemical chameleons in organic synthesis. Here we present a ligand coupling-enabled formal SO2 extrusion of fluoroalkyl 2-azaheteroarylsulfones under the promotion of Grignard reagents, which not only enriches the chemistry of sulfones, but also provides a novel and practical synthetic tool towards N-heteroaromatic fluoroalkylation.

2.
Plant Dis ; 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37859340

RESUMEN

Hami melon (Cucumis melon var. saccharinus) is an economically important crop all over the world. It is being extensively planted in greenhouse in the southwest part of Hainan province, China. A new bacterial leaf spot was observed in a 20 hm2 Hami melon plantation in Huangliu town, Ledong county, Hainan province, in January 2022. The incidence of the disease was approximately 5%. Symptoms were irregularly shaped, brown lesions with yellow haloes on mature leaves, and first appeared as small, dark-green, water-soaking spots. Specimens from the lesion margin were disinfected by submersion in 0.1% mercuric chloride for 1 min, then soaked with 75% alcohol for 30 s, and rinsed with sterilized distilled water. The tissues were then ground in 2 ml of sterile water and allowed to stand for 5min. The supernatant was streaked onto nutrient agar (NA) and incubated for 48h at 30°C. Colonies were round, smooth, colorless, nearly transparent, bead-shaped at first, and then became lightly blue. After being cultured for days on NA at 30℃, the bacteria can turn the media brown. Yellow green pigments (pyoverdin) that fluoresce under ultraviolet light could be produced by the isolates in the Luria Broth. The bacteria were gram-negative, rod shaped with a single polar flagellum, 0.4 to 1.1 × 1.4 to 3.4 µm. Its physiological and biochemical characteristics were as follows: positive for the oxidase, aerobic, arginine dihydrolase, gelatin liquefaction, denitrification, lipase, growth at 41℃, utilization of mannitol, and production of pyocyanin tests; negative for the hydrolysis of starch, levan formation, lecithinase, growth at 4℃, growth in media supplemented with 8.5% NaCl, and utilization of maltose, xylose, and ethylene glycol tests. The 16S rRNA (1,437 bp), gyrB (1,181 bp), and rpoB genes (1,510 bp) were amplified with 27F/1492R (Zhang et al. 2016), UP-1s/UP-2sr(Hannula M,2007), and rpoB-F/rpoB-R (Ogier, JC. et al., 2019) primer sets respectively. One of the 5 isolates collected was sequenced. A BLASTn search of GenBank revealed that the sequence of 16S rRNA gene (OQ918303) had 99.7% identity and 98% coverage comparing with the best hit Pseudomonas aeruginosa strain DSM 50071(NR_117678.1), and both gyrB (OR261077) and rpoB (OR261078) had 99.9% identity and over 98% coverage comparing with P. aeruginosa E90 (CP044006.1). A pathogenicity test was conducted by spraying a suspension of the bacteria (108 CFU/mL) onto 10 Hami melon seedlings with two true leaves. Controls were inoculated with sterile water. All inoculated plants were maintained at 28℃ with 80 to 85% relative humidity in a greenhouse. Dark-green, water soaking spots appeared on the cotyledon and stems of treated seedlings 3-5 days after inoculation, and dark green lesions with halos were observed on the true leaves at the same time. Symptoms did not occur on the control plants. The bacteria which were re-isolated from the inoculated plants were confirmed as P. aeruginosa based on the 16S rRNA gene sequence. The bacterium was not isolated from control plants. P. aeruginosa has been reported to cause disease on a variety of plants including tomato (Zhang et al., 2021), poplar (Liu, et al., 2019), ginseng (Gao et al., 2014), tinda (Mondal et al., 2012), onion (Abd-Alla et al., 2011), tobacco (Yu et al., 2008) and sweet basil (Walker et al., 2004). As far as we know, this is the first report of P. aeruginosa causing leaf spot on Hami melon in China.. This report will contribute to the recognition and diagnosis of the new disease for the Hami melon growers.

3.
Shock ; 60(5): 713-723, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37752084

RESUMEN

ABSTRACT: Hypertension seems to inevitably cause cardiac remodeling, increasing the mortality of patients. This study aimed to explore the molecular mechanism of CCAAT/enhancer-binding protein delta (CEBPD)-mediated oxidative stress and inflammation in hypertensive cardiac remodeling. The hypertensive murine model was established through angiotensin-II injection, and hypertensive mice underwent overexpressed CEBPD vector injection, cardiac function evaluation, and observation of histological changes. The cell model was established by angiotensin-II treatment and transfected with overexpressed CEBPD vector. Cell viability and surface area and oxidative stress (reactive oxygen species/superoxide dismutase/lactate dehydrogenase/malondialdehyde) were assessed, and inflammatory factors (TNF-α/IL-1ß/IL-6/IL-10) were determined both in vivo and in vitro . The levels of CEBPD, miR-96-5p, inositol 1,4,5-trisphosphate receptor 1 (IP3R), natriuretic peptide B, and natriuretic peptide A, collagen I, and collagen III in tissues and cells were determined. The binding relationships of CEBPD/miR-96-5p/IP3R 3' untranslated region were validated. CEBPD was reduced in cardiac tissue of hypertensive mice, and CEBPD upregulation improved cardiac function and attenuated fibrosis and hypertrophy, along with reductions of reactive oxygen species/lactate dehydrogenase/malondialdehyde/TNF-α/IL-1ß/IL-6 and increases in superoxide dismutase/IL-10. CEBPD enriched on the miR-96-5p promoter to promote miR-96-5p expression, whereas CEBPD and miR-96-5p negatively regulated IP3R. miR-96-5p silencing/IP3R overexpression reversed the alleviative role of CEBPD overexpression in hypertensive mice. In summary, CEBPD promoted miR-96-5p to negatively regulate IP3R expression to inhibit oxidative stress and inflammation, thereby alleviating hypertensive cardiac remodeling.


Asunto(s)
Hipertensión , MicroARNs , Humanos , Ratones , Animales , MicroARNs/genética , MicroARNs/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Interleucina-10/metabolismo , Proteína delta de Unión al Potenciador CCAAT/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Remodelación Ventricular/genética , Interleucina-6/metabolismo , Estrés Oxidativo , Inflamación/metabolismo , Hipertensión/genética , Péptidos Natriuréticos/metabolismo , Colágeno/metabolismo , Superóxido Dismutasa/metabolismo , Malondialdehído , Lactato Deshidrogenasas/metabolismo , Angiotensinas/metabolismo , Apoptosis
4.
Biomed Pharmacother ; 162: 114733, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37087977

RESUMEN

Doxorubicin (DOX) is an anthracycline antineoplastic agent that has limited clinical utility due to its dose-dependent cardiotoxicity. Although the exact mechanism remains unknown, inflammatory responses have been implicated in DOX-induced cardiotoxicity (DIC). In this study, we analyzed the transcriptomic, metabolomic as well as lipidomic changes in the DOX-treated mice to explore the underlying mechanisms of DIC. We found that continuous intraperitoneal DOX injections (3 mg/kg/d) for a period of five days significantly induced cardiac dysfunction and cardiac injury in male C57BL/6 J mice (8 weeks old). This corresponded to a significant increase in the myocardial levels of IL-4, IL-6, IL-10, IL-17 and IL-12p70. Furthermore, inflammation-related genes such as Ptgs2, Il1b, Cxcl5, Cxcl1, Cxcl2, Mmp3, Ccl2, Ccl12, Nfkbia, Fos, Mapk11 and Tnf were differentially expressed in the DOX-treated group, and enriched in the IL-17 and TNF signaling pathways. Besides, amino acids, peptides, imidazoles, toluenes, hybrid peptides, fatty acids and lipids such as Hex1Cer, Cer, SM, PG and ACCa were significantly associated with the expression pattern of inflammation-related genes. In conclusion, the integration of transcriptomic, metabolomic and lipidomic data identified potential new targets and biomarkers of DIC.


Asunto(s)
Cardiotoxicidad , Interleucina-17 , Ratones , Masculino , Animales , Cardiotoxicidad/metabolismo , Interleucina-17/metabolismo , Lipidómica , Transcriptoma , Ratones Endogámicos C57BL , Doxorrubicina/efectos adversos , Inflamación/metabolismo , Estrés Oxidativo , Miocitos Cardíacos/metabolismo , Apoptosis
5.
Neurospine ; 20(4): 1358-1379, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38171303

RESUMEN

OBJECTIVE: Herein, we investigated whether mesenchymal stem cells (MSCs) transplantation combined with electroacupuncture (EA) treatment could decrease the proportion of proinflammatory microglia/macrophages and neurotoxic A1 reactive astrocytes and inhibit glial scar formation to enhance axonal regeneration after spinal cord injury (SCI). METHODS: Adult rats were divided into 5 groups after complete transection of the spinal cord at the T10 level: a control group, a nonacupoint EA (NA-EA) group, an EA group, an MSC group, and an MSCs+EA group. Immunofluorescence labeling, quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blots were performed. RESULTS: The results showed that MSCs+EA treatment reduced the proportion of proinflammatory M1 subtype microglia/macrophages, but increased the differentiation of anti-inflammatory M2 phenotype cells, thereby suppressing the mRNA and protein expression of proinflammatory cytokines (tumor necrosis factor-α and IL-1ß) and increasing the expression of an anti-inflammatory cytokine (interleukin [IL]-10) on days 7 and 14 after SCI. The changes in expression correlated with the attenuated neurotoxic A1 reactive astrocytes and glial scar, which in turn facilitated the axonal regeneration of the injured spinal cord. In vitro, the proinflammatory cytokines increased the level of proliferation of astrocytes and increased the expression levels of C3, glial fibrillary acidic protein, and chondroitin sulfate proteoglycan. These effects were blocked by administering inhibitors of ErbB1 and signal transducer and activator of transcription 3 (STAT3) (AG1478 and AG490) and IL-10. CONCLUSION: These findings showed that MSCs+EA treatment synergistically regulated the microglia/macrophage subpopulation to reduce inflammation, the formation of neurotoxic A1 astrocytes, and glial scars. This was achieved by downregulating the ErbB1-STAT3 signal pathway, thereby providing a favorable microenvironment conducive to axonal regeneration after SCI.

6.
Chemistry ; 27(71): 17773-17779, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34648215

RESUMEN

The ring-opening difluoromethylation-halogenation of cyclic (thio)ethers is reported through a simple strategy relying on carbon-chalcogen bond activation with difluorocarbene. The reaction proceeds through in situ protonation of the previously little-known difluoromethylene oxonium or sulfonium ylide intermediate followed by ring-opening with halide ion to afford halogenated acyclic difluoromethyl (thio)ethers that can then be employed for further elaboration. TMSCF2 X (X=Br, Cl) are unique reagents to achieve this synthetic purpose, which serve as both the difluorocarbene source and the halide ion source.

7.
PLoS One ; 16(7): e0254808, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34293017

RESUMEN

MicroRNA-like small RNAs (milRNAs) and their regulatory roles in the interaction between plant and fungus have recently aroused keen interest of plant pathologists. Trichoderma spp., one of the widespread biocontrol fungi, can promote plant growth and induce plant disease resistance. To investigate milRNAs potentially involved in the interaction between Trichoderma and tomato roots, a small RNA (sRNA) library expressed during the interaction of T. asperellum DQ-1 and tomato roots was constructed and sequenced using the Illumina HiSeqTM 2500 sequencing platform. From 13,464,142 sRNA reads, we identified 21 milRNA candidates that were similar to other known microRNAs in the miRBase database and 22 novel milRNA candidates that possessed a stable microRNA precursor hairpin structure. Among them, three milRNA candidates showed different expression level in the interaction according to the result of stem-loop RT-PCR indicating that these milRNAs may play a distinct regulatory role in the interaction between Trichoderma and tomato roots. The potential transboundary milRNAs from T. asperellum and their target genes in tomato were predicted by bioinformatics analysis. The results revealed that several interesting proteins involved in plant growth and development, disease resistance, seed maturation, and osmotic stress signal transduction might be regulated by the transboundary milRNAs. To our knowledge, this is the first report of milRNAs taking part in the process of interaction of T. asperellum and tomato roots and associated with plant promotion and disease resistance. The results might be useful to unravel the mechanism of interaction between Trichoderma and tomato.


Asunto(s)
Interacciones Huésped-Patógeno/fisiología , Hypocreales/fisiología , MicroARNs/biosíntesis , Raíces de Plantas/microbiología , ARN de Hongos/biosíntesis , Solanum lycopersicum/microbiología , Resistencia a la Enfermedad/fisiología , MicroARNs/genética , ARN de Hongos/genética
8.
J Int Med Res ; 47(1): 453-469, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30477383

RESUMEN

OBJECTIVE: This study aimed to examine regulation of capillary tubules and lipid formation in vascular endothelial cells and macrophages via extracellular vesicle-mediated microRNA (miRNA)-4306 transfer. METHODS: Whole blood samples (12 mL) were collected from 53 patients, and miR-4306 levels in extracellular vesicles (EVs) were analyzed by reverse transcription-polymerase chain reaction. Human coronary artery vascular endothelial cells (HCAECs) and human monocyte-derived macrophages (HMDMs) were transfected with a scrambled oligonucleotide, an miR-4306 mimic, or an anti-miR-4306 inhibitor. The direct effect of miR-4306 on the target gene was analyzed by a dual-luciferase reporter assay. RESULTS: EV-contained miR-4306 released from HMDMs was significantly upregulated in coronary artery disease. Oxidized low-density lipoprotein (ox-LDL)-stimulated HMDM-derived EVs inhibited proliferation, migration, and angiogenesis abilities of HCAECs in vitro. However, ox-LDL-stimulated HCAEC-derived EVs enhanced lipid formation of HMDMs. The possible mechanism of these findings was partly due to EV-mediated miR-4306 upregulation of the Akt/nuclear factor kappa B signaling pathway. CONCLUSIONS: Paracrine cellular crosstalk between HCAECs and HMDMs probably supports the pro-atherosclerotic effects of EVs under ox-LDL stress.


Asunto(s)
Enfermedad de la Arteria Coronaria/metabolismo , Células Endoteliales/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , MicroARNs/genética , Antagomirs/genética , Antagomirs/metabolismo , Estudios de Casos y Controles , Movimiento Celular , Proliferación Celular , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/cirugía , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Vesículas Extracelulares/química , Regulación de la Expresión Génica , Genes Reporteros , Humanos , Lipoproteínas LDL/farmacología , Luciferasas/genética , Luciferasas/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/patología , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , MicroARNs/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Oligorribonucleótidos/genética , Oligorribonucleótidos/metabolismo , Comunicación Paracrina , Intervención Coronaria Percutánea , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
9.
Clin Exp Hypertens ; 41(5): 481-491, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30183452

RESUMEN

Platelets are major sources of microparticles (MPs) in peripheral bloodstream, and platelet-secreted MPs (P-MPs) transfer biological information to neighboring cells. In the present study, we found that the platelet- and P-MPs-derived microRNA-4306 (miR-4306) expression were downregulated in coronary artery disease (CAD) and platelet-derived miR-4306 was an independent poor prognostic factor in CAD. Plasma miRNA-4306 mainly cofractionated with MPs instead of Argonaute2 complexes or HDL. P-MPs could effectively deliver miR-4306 into human monocyte-derived macrophages (HMDMs). MiR-4306 noticeably inhibited the HMDMs migration in vitro and reduced the number of macrophage cells in cardiac tissue in myocardial infarction mice. This functional impact of miR-4306 was mediated directly through VEGFA to inhibit ERK/NF-κB signaling. In conclusion, our study suggested that intercellular transfer of miR-4306 by platelet microparticles inhibited the HMDMs migration through VEGFA/ERK1/2/NF-κB signaling pathways.


Asunto(s)
Plaquetas , Movimiento Celular/genética , Micropartículas Derivadas de Células/genética , Enfermedad de la Arteria Coronaria/sangre , Macrófagos/fisiología , MicroARNs/genética , Animales , Plaquetas/metabolismo , Células Cultivadas , Regulación hacia Abajo , Células HEK293 , Humanos , Sistema de Señalización de MAP Quinasas , Macrófagos/patología , Ratones , MicroARNs/sangre , Monocitos , Infarto del Miocardio/patología , FN-kappa B/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
Angew Chem Int Ed Engl ; 57(40): 13211-13215, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30138542

RESUMEN

A highly efficient copper-mediated aromatic pentafluoroethylation method using TMSCF3 as the sole fluoroalkyl source is described. The reaction proceeds by a key C1 to C2 process, that is, the generation of CuCF3 from TMSCF3 , followed by a subsequent spontaneous transformation into CuC2 F5 . Various aryl iodides were pentafluoroethylated with the TMSCF3 -derived CuC2 F5 . This method represents the first practical and efficient method for pentafluoroethylation of aryl iodides using commercially available TMSCF3 as a pentafluoroethyl precursor.

11.
Org Biomol Chem ; 15(39): 8302-8307, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-28933498

RESUMEN

An Ir(iii)-catalyzed regioselective C-H amidation of anilines with sulfonyl azides is described. The developed protocol has good compatibility with diverse functional groups, efficiently providing the monoamidated products with good to excellent yields under mild reaction conditions. Furthermore, the 2-pyrimidyl and sulfonyl moieties in the amidated products can readily be removed, offering the synthetically useful 1,2-diaminobenzene scaffold.

12.
Cell Physiol Biochem ; 42(5): 2130-2143, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28810263

RESUMEN

BACKGROUND/AIMS: C1q and tumour necrosis factor-related protein 1 (CTRP1) possesses anti-atherogenic and anti-inflammatory effects. This study investigated whether the CTRP1 levels in the plasma and epicardial adipose tissue (EAT) were associated with congestive heart failure (CHF) and to disclose possible molecular mechanisms. METHODS: Plasma and tissue samples were obtained from subjects with or without CHF. Plasma levels of CTRP1 were measured by ELISA. The mRNA levels of CTRP1 and inflammatory cytokines were detected by RT-PCR. The protein levels of CTRP1, aldosterone synthase (CYP11B2) and mitogen-activated protein kinase were examined by Western blotting. RESULTS: The levels of CTRP1 in the plasma and EAT were higher in the CHF patients than those in the controls. There were no differences in the CTRP1 levels in cardiomyocytes between the CHF group and the non-CHF group. An exploratory survival analysis showed that higher CTRP1 values at admission were associated with a worse prognosis after discharge. CTRP1 increased the IL-6 mRNA level in H295R cells. CTRP1 recruited ERK1/2 and Jak-2 for aldosterone release by modulating the CYP11B2 protein level, and brain natriuretic peptide repressed the CTRP1-induced aldosterone release through the JAK2-STAT3 signalling pathways. CONCLUSION: The CTRP1 levels in the plasma and EAT were increased in the CHF patients. CTRP1 is involved in the pathogenesis of CHF by modulating IL-6 levels and aldosterone release.


Asunto(s)
Tejido Adiposo/metabolismo , Insuficiencia Cardíaca/patología , Proteínas/análisis , Anciano , Aldosterona/sangre , Aldosterona/metabolismo , Estudios de Casos y Controles , Línea Celular , Estudios Transversales , Citocromo P-450 CYP11B2/metabolismo , Citocinas/análisis , Citocinas/genética , Citocinas/metabolismo , Femenino , Insuficiencia Cardíaca/congénito , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/mortalidad , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas/genética , Proteínas/metabolismo , Proteínas/farmacología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
13.
Angew Chem Int Ed Engl ; 56(12): 3206-3210, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28181719

RESUMEN

A general method for the efficient difluoromethylation of alcohols using commercially available TMSCF2 Br (TMS=trimethylsilyl) as a unique and practical difluorocarbene source is developed. This method allows primary, secondary, and even tertiary alkyl difluoromethyl ethers to be synthesized under weakly basic or acidic conditions. The reaction mainly proceeds through the direct interaction between a neutral alcohol and difluorocarbene, which is different from the difluoromethylation of phenols. Moreover, alcohols containing other moieties that are also reactive toward difluorocarbene can be transformed divergently by using TMSCF2 Br. This research not only solves the synthetic problem of difluorocarbene-mediated difluoromethylation of alcohols, it also provides new insights into the different reaction mechanisms of alcohol difluoromethylation and phenol difluoromethylation with difluorocarbene species.

14.
Acupunct Med ; 35(2): 122-132, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27841975

RESUMEN

OBJECTIVES: In spinal cord demyelination, some oligodendrocyte precursor cells (OPCs) remain in the demyelinated region but have a reduced capacity to differentiate into oligodendrocytes. This study investigated whether 'Governor Vessel' (GV) electroacupuncture (EA) would promote the differentiation of endogenous OPCs into oligodendrocytes by activating the retinoid X receptor γ (RXR-γ)-mediated signalling pathway. METHODS: Adult rats were microinjected with ethidium bromide (EB) into the T10 spinal cord to establish a model of spinal cord demyelination. EB-injected rats remained untreated (EB group, n=26) or received EA treatment (EB+EA group, n=26). A control group (n=26) was also included that underwent dural exposure without EB injection. After euthanasia at 7 days (n=5 per group), 15 days (n=8 per group) or 30 days (n=13 per group), protein expression of RXR-γ in the demyelinated spinal cord was evaluated by immunohistochemistry and Western blotting. In addition, OPCs derived from rat embryonic spinal cord were cultured in vitro, and exogenous 9-cis-RA (retinoic acid) and RXR-γ antagonist HX531 were administered to determine whether RA could activate RXR-γ and promote OPC differentiation. RESULTS: EA was found to increase the numbers of both OPCs and oligodendrocytes expressing RXR-γ and RALDH2, and promote remyelination in the remyelinated spinal cord. Exogenous 9-cis-RA enhanced the differentiation of OPCs into mature oligodendrocytes by activating RXR-γ. CONCLUSIONS: The results suggest that EA may activate RXR signalling to promote the differentiation of OPCs into oligodendrocytes in spinal cord demyelination.


Asunto(s)
Diferenciación Celular , Enfermedades Desmielinizantes/terapia , Electroacupuntura , Oligodendroglía/citología , Receptores X Retinoide/metabolismo , Animales , Enfermedades Desmielinizantes/metabolismo , Femenino , Humanos , Oligodendroglía/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Médula Espinal/metabolismo
15.
PLoS One ; 10(12): e0144030, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26640949

RESUMEN

Cholera toxin B subunit (CTB) has been extensively used in the past for monosynaptic mapping. For decades, it was thought to lack the ability of transneuronal tracing. In order to investigate whether biotin conjugates of CTB (b-CTB) would pass through transneurons in the rat spinal cord, it was injected into the crushed left sciatic nerve. For experimental control, the first order afferent neuronal projections were defined by retrograde transport of fluorogold (FG, a non-transneuronal labeling marker as an experimental control) injected into the crushed right sciatic nerve in the same rat. Neurons containing b-CTB or FG were observed in the dorsal root ganglia (DRG) at the L4-L6 levels ipsilateral to the tracer injection. In the spinal cord, b-CTB labeled neurons were distributed in all laminae ipsilaterally between C7 and S1 segments, but labeling of neurons at the cervical segment was abolished when the T10 segment was transected completely. The interneurons, distributed in the intermediate gray matter and identified as gamma-aminobutyric acid-ergic (GABAergic), were labeled by b-CTB. In contrast, FG labeling was confined to the ventral horn neurons at L4-L6 spinal segments ipsilateral to the injection. b-CTB immunoreactivity remained to be restricted to the soma of neurons and often appeared as irregular patches detected by light and electron microscopy. Detection of monosialoganglioside (GM1) in b-CTB labeled neurons suggests that GM1 ganglioside may specifically enhance the uptake and transneuronal passage of b-CTB, thus supporting the notion that it may be used as a novel transneuronal tracer.


Asunto(s)
Toxina del Cólera , Neuronas GABAérgicas/citología , Ganglios Espinales/citología , Sustancia Gris/citología , Técnicas de Trazados de Vías Neuroanatómicas/métodos , Nervio Ciático/citología , Animales , Toxina del Cólera/farmacocinética , Toxina del Cólera/farmacología , Femenino , Gangliósido G(M1)/metabolismo , Neuronas GABAérgicas/metabolismo , Ganglios Espinales/metabolismo , Sustancia Gris/metabolismo , Ratas , Ratas Sprague-Dawley , Nervio Ciático/metabolismo
16.
Stem Cell Res Ther ; 6: 105, 2015 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-26012641

RESUMEN

INTRODUCTION: Severe spinal cord injury often causes temporary or permanent damages in strength, sensation, or autonomic functions below the site of the injury. So far, there is still no effective treatment for spinal cord injury. Mesenchymal stem cells (MSCs) have been used to repair injured spinal cord as an effective strategy. However, the low neural differentiation frequency of MSCs has limited its application. The present study attempted to explore whether the grafted MSC-derived neural-like cells in a gelatin sponge (GS) scaffold could maintain neural features or transdifferentiate into myelin-forming cells in the transected spinal cord. METHODS: We constructed an engineered tissue by co-seeding of MSCs with genetically enhanced expression of neurotrophin-3 (NT-3) and its high-affinity receptor tropomyosin receptor kinase C (TrkC) separately into a three-dimensional GS scaffold to promote the MSCs differentiating into neural-like cells and transplanted it into the gap of a completely transected rat spinal cord. The rats received extensive post-operation care, including cyclosporin A administrated once daily for 2 months. RESULTS: MSCs modified genetically could differentiate into neural-like cells in the MN + MT (NT-3-MSCs + TrKC-MSCs) group 14 days after culture in the GS scaffold. However, after the MSC-derived neural-like cells were transplanted into the injury site of spinal cord, some of them appeared to lose the neural phenotypes and instead transdifferentiated into myelin-forming cells at 8 weeks. In the latter, the MSC-derived myelin-forming cells established myelin sheaths associated with the host regenerating axons. And the injured host neurons were rescued, and axon regeneration was induced by grafted MSCs modified genetically. In addition, the cortical motor evoked potential and hindlimb locomotion were significantly ameliorated in the rat spinal cord transected in the MN + MT group compared with the GS and MSC groups. CONCLUSION: Grafted MSC-derived neural-like cells in the GS scaffold can transdifferentiate into myelin-forming cells in the completely transected rat spinal cord.


Asunto(s)
Axones/fisiología , Células Madre Mesenquimatosas/citología , Vaina de Mielina/metabolismo , Células-Madre Neurales/trasplante , Traumatismos de la Médula Espinal/terapia , Adenoviridae/genética , Animales , Conducta Animal , Técnicas de Cultivo de Célula , Transdiferenciación Celular , Células Cultivadas , Femenino , Células Madre Mesenquimatosas/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Transgénicas , Receptor trkC/genética , Receptor trkC/metabolismo , Recuperación de la Función , Regeneración , Andamios del Tejido
17.
Sci Rep ; 5: 9133, 2015 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-25779025

RESUMEN

This study attempted to graft neurotrophin-3 (NT-3) receptor (TrkC) gene modified mesenchymal stem cells (TrkC-MSCs) into the demyelinated spinal cord and to investigate whether electroacupuncture (EA) treatment could promote NT-3 secretion in the demyelinated spinal cord as well as further enhance grafted TrkC-MSCs to differentiate into oligodendrocytes, remyelination and functional recovery. Ethidium bromide (EB) was microinjected into the spinal cord of rats at T10 to establish a demyelinated model. Six groups of animals were prepared for the experiment: the sham, PBS, MSCs, MSCs+EA, TrkC-MSCs and TrkC-MSCs+EA groups. The results showed that TrkC-MSCs graft combined with EA treatment (TrkC-MSCs+EA group) significantly increased the number of OPCs and oligodendrocyte-like cells differentiated from MSCs. Immunoelectron microscopy showed that the oligodendrocyte-like cells differentiated from TrkC-MSCs formed myelin sheaths. Immunofluorescence histochemistry and Western blot analysis indicated that TrkC-MSCs+EA treatment could promote the myelin basic protein (MBP) expression and Kv1.2 arrangement trending towards the normal level. Furthermore, behavioural test and cortical motor evoked potentials detection demonstrated a significant functional recovery in the TrkC-MSCs+EA group. In conclusion, our results suggest that EA treatment can increase NT-3 expression, promote oligodendrocyte-like cell differentiation from TrkC-MSCs, remyelination and functional improvement of demyelinated spinal cord.


Asunto(s)
Enfermedades Desmielinizantes/genética , Electroacupuntura , Expresión Génica , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Receptor trkC/genética , Enfermedades de la Médula Espinal/genética , Adenoviridae/genética , Animales , Diferenciación Celular , Enfermedades Desmielinizantes/metabolismo , Enfermedades Desmielinizantes/terapia , Modelos Animales de Enfermedad , Potenciales Evocados Motores , Vectores Genéticos/genética , Células Madre Mesenquimatosas/citología , Vaina de Mielina/metabolismo , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Oligodendroglía/citología , Oligodendroglía/metabolismo , Ratas , Receptor trkC/metabolismo , Recuperación de la Función , Enfermedades de la Médula Espinal/metabolismo , Enfermedades de la Médula Espinal/terapia , Transducción Genética , Transgenes
18.
Cell Transplant ; 24(7): 1265-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24856958

RESUMEN

Transplantation of bone marrow mesenchymal stem cells (MSCs) promotes functional recovery in multiple sclerosis (MS) patients and in a murine model of MS. However, there is only a modicum of information on differentiation of grafted MSCs into oligodendrocyte-like cells in MS. The purpose of this study was to transplant neurotrophin-3 (NT-3) and retinoic acid (RA) preinduced MSCs (NR-MSCs) into a demyelinated spinal cord induced by ethidium bromide and to investigate whether EA treatment could promote NT-3 secretion in the demyelinated spinal cord. We also sought to determine whether increased NT-3 could further enhance NR-MSCs overexpressing the tyrosine receptor kinase C (TrkC) to differentiate into more oligodendrocyte-like cells, resulting in increased remyelination and nerve conduction in the spinal cord. Our results showed that NT-3 and RA increased transcription of TrkC mRNA in cultured MSCs. EA increased NT-3 levels and promoted differentiation of oligodendrocyte-like cells from grafted NR-MSCs in the demyelinated spinal cord. There was evidence of myelin formation by grafted NR-MSCs. In addition, NR-MSC transplantation combined with EA treatment (the NR-MSCs + EA group) reduced demyelination and promoted remyelination. Furthermore, the conduction of cortical motor-evoked potentials has improved compared to controls. Together, our data suggest that preinduced MSC transplantation combined with EA treatment not only increased MSC differentiation into oligodendrocyte-like cells forming myelin sheaths, but also promoted remyelination and functional improvement of nerve conduction in the demyelinated spinal cord.


Asunto(s)
Electroacupuntura/métodos , Esclerosis Múltiple/genética , Esclerosis Múltiple/fisiopatología , Neurotrofina 3/química , Traumatismos de la Médula Espinal/terapia , Tretinoina/química , Animales , Diferenciación Celular , Masculino , Ratones , Oligodendroglía , Ratas , Ratas Sprague-Dawley
19.
Springerplus ; 2: 543, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24255843

RESUMEN

Bacillus subtilis B25 was isolated from banana rhizosphere soil. It has been confirmed for B25 to have stronger antagonism against Fusarium oxysporum f.sp.cubense, Additionally B25 has good inhibitory to plant pathogens, including Corynespora cassiicola, Alternaria solani, Botrytis cinerea and Colletotrichum gloeosporioides on potato dextrose agar (PDA) plates. The antagonistic substance can be extracted from cell-free culture broth supernatants by 70% (w/v) (NH4)2 SO4 saturation. Clear blank band was observed between the protein and a pathogen. The examination of antagonistic mechanism under light microscope showed that the antifungal protein of B25 appeared to inhibit pathogens by leading to mycelium and spores tumescence, distortion, abnormality. The isolation procedure comprised ion exchange chromatography on DEAE-Sephadex Fast Flow and gel filtration chromatography on SephadexG-100. The purified antifungal fraction showed a single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The active fraction was identified by NanoLC-ESI-MS/MS The amino acid sequences of 17 peptides segments were obtained. The analysis of the protein suggested that it was a hypothetical protein (gi154685475), with a relative molecular mass of 38708.67 Da and isoelectric point (pI) of 5.63.

20.
Chem Commun (Camb) ; 49(80): 9167-9, 2013 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-23989459

RESUMEN

An efficient synthesis of bifurans via dimerization of cyclopropenes has been successfully developed using a copper-promoted cycloisomerization and palladium-catalyzed dimerization cascade. These novel bifuran structures possess interesting optoelectronic properties.

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