Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Dev Comp Immunol ; 106: 103613, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31935401

RESUMO

Teleost fish are the most primitive bony vertebrates that contain B cells; thus, comparative analysis of teleost naïve/mature B cells and plasma cells can provide helpful evidence for understanding the evolution paradigms of these two B-cell subpopulations in vertebrates. In this study, we developed monoclonal antibody against grass carp IgM and identified two different IgM+ cell subsets: IgM+ lymphocytes (Lym), resembling naïve/mature B cells, and IgM+ myeloid cells (Mye), resembling plasma cells. Like plasma cells in mammals, the size of IgM+ Mye is significantly larger than that of IgM+ Lym, as revealed by flow cytometric analysis and transmission electron microscopy. The IgM+ Mye were further verified as plasma cells because they showed gene expression patterns similar with those of human plasma cells and a great capacity to secrete IgM. Like mammalian IgM+ and IgA+ plasma cells, not IgG+ plasma cells, grass carp IgM+ Mye also expressed membrane immunoglobulins, a feature conserved in IgM+ plasma cells in vertebrates. Furthermore, recombinant CD40L or IL-21 alone could induce the plasma cell generation and IgM secretion, while the combination of CD40L and IL-21 had greater effect on IgM secretion, but not on plasma cell generation. This study fills an important gap in the knowledge of plasma cells in teleost fish and provides critical insights into the conserved evolution of IgM+ plasma cells in vertebrates.

2.
J Am Chem Soc ; 141(25): 10033-10038, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31140278

RESUMO

Recently, we discovered a modular synthetic approach for constructing core-shell columnar liquid crystals (LCs) by supramolecular polymerization in LC media. In the present work, we successfully confirmed that our modular synthetic approach has the potential to be widely extended to the development of multifunctional columnar LCs. Herein, we constructed the first core-shell columnar LC that was proved to be orientable by both electric and magnetic fields by the supramolecular polymerization of NODiskNH* in a nematic LC medium of 4-cyano-4'-pentyloxybiphenyl (5OCB). NODiskNH* is a chiral benzenetricarboxamide derivative bearing 2,2,6,6-tetramethylpiperidine 1-oxyl termini, which is known to form a helical supramolecular polymer via a triple hydrogen-bonding array. NODiskNH* alone formed a hydrogen-bonded liquid phase without any long-range structural ordering. However, a nematic LC medium of 5OCB, when mixed with NODiskNH* at a molar ratio of 1:3, underwent a "structural order-increasing" mesophase transition, affording an optically active single LC phase with a hexagonally arranged core-shell columnar geometry in a temperature range from 113 to 51 °C. Unprecedentedly, this core-shell columnar LC can orient its columns both electrically and magnetically, resulting in unidirectional columnar ordering.

3.
Fish Shellfish Immunol ; 89: 301-308, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30965085

RESUMO

Indoleamine 2,3-dioxygenase (IDO) is a kind of dioxygenase that can catalyze the degradation of levo-tryptophan (L-Trp) and plays key roles in immune tolerance. In this study, the IDO gene was cloned and functionally characterized from grass carp (gcIDO). The results showed that gcIDO overexpressed in GCO cells could catalyze the degradation of L-Trp through the L-Trp - kynurenine pathway, and this activity could be promoted by δ-aminolevulinic acid (ALA) while inhibited by levo-1-methyl tryptophan (L-1MT). Moreover, gcIDO was constitutively expressed in various tissues, and its expression could be significantly up-regulated by LPS and Poly (I:C) in peripheral blood leukocytes (PBLs). Furthermore, recombinant TGF-ß1 of grass carp could up-regulate the expression of IDO, TGF-ß1, CD25, and Foxp3 in PBLs, indicating that the TGF-ß1/IDO pathway is present in fish. In the soybean meal induced enteritis (SBMIE) model, the expression of gcIDO in the intestine was up-regulated significantly, demonstrating that gcIDO may play an immunoregulatory role in SBMIE. Taken together, these data suggest that the IDO plays multiple roles in the immunity of fish.


Assuntos
Carpas/genética , Enterite/veterinária , Doenças dos Peixes/genética , Regulação da Expressão Gênica/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Animais , Carpas/imunologia , Enterite/induzido quimicamente , Enterite/genética , Enterite/imunologia , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Lipopolissacarídeos/farmacologia , Poli I-C/farmacologia , Soja/química , Fator de Crescimento Transformador beta1/genética
4.
Dev Comp Immunol ; 89: 73-82, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30107249

RESUMO

In mammals, the binding of distinct costimulatory ligands CD80 and CD86 to their receptors is essential for optimal T cell activation. Previous studies have shown that only a single CD80/86 gene exists in rainbow trout (termed rtCD80/86A) and other teleost fish, suggesting that CD80 and CD86 arose by gene duplication in the tetrapod branch, after the separation of fish and tetrapods. However, in this study, another CD80/86 gene has been cloned from rainbow trout, termed rtCD80/86B. The sequence identity between trout CD80/86 is significantly higher than that between CD80 and CD86 in tetrapods, indicating that CD80 and CD86 underwent divergent evolution in vertebrates, especially in tetrapods. Gene synteny analyses showed that the CD80 and CD86 genes are closely located in the same chromosome in tetrapods. However, CD80/86 genes are located in two distinct chromosomes in rainbow trout and Atlantic salmon, suggesting that salmonid CD80/86 genes arose by the salmonid-specific whole-genome duplication (WGD) event. Expression analysis showed that rtCD80/86A was more abundant and inducible than rtCD80/86B in various tissues, indicating the important role of rtCD80/86A in trout immunity. Interestingly, we found that head kidney B cells showed higher expression level of rtCD80/86A and rtCD80/86B when compared with the other leukocytes, suggesting a potential role for trout B cells as antigen-presenting cells (APCs).


Assuntos
Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/imunologia , DNA Complementar/genética , Evolução Molecular , Duplicação Gênica , Expressão Gênica , Filogenia , Homologia de Sequência de Aminoácidos , Sintenia , Linfócitos T/imunologia , Distribuição Tecidual , Vertebrados/genética , Vertebrados/imunologia
5.
Front Immunol ; 8: 388, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28421080

RESUMO

B cells in fish were recently proven to have potent innate immune activities like macrophages. This inspired us to further explore the innate nature of B cells in fish. Moreover, antimicrobial peptides (AMPs) are representative molecules of innate immunity, and they can modulate the functions of macrophages. These make fish an appropriate model to study the interactions between B cells and AMPs. Interestingly, the results in this study revealed that the IgM+ and IgT+ B cells of rainbow trout could express multiple AMP genes, including four cathelicidin genes and one ß-defensin gene. The expression levels of the cathelicidin genes were obviously higher than that of the ß-defensin gene. Further studies revealed that intracellular, extracellular, in vitro, and in vivo stimulations could significantly increase the expression of the cathelicidin genes in trout IgM+ and IgT+ B cells but not the expression of the ß-defensin gene, indicating that cathelicidin peptides are the main innate immune effectors of trout B cells. More interestingly, we found that cathelicidin peptides could significantly enhance the phagocytic, intracellular bactericidal, and reactive oxygen species activities of trout IgM+ and IgT+ B cells, a phenomenon previously reported only in macrophages, and these activities might also be mediated by the P2X7 receptor. These results collectively suggest that B cells play multiple roles in the innate immunity of fish, and they provide new evidence for understanding the close relationship between B cells and macrophages in vertebrates.

6.
Dev Comp Immunol ; 70: 94-105, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28062226

RESUMO

As the teleost specific immunoglobulin, IgT plays important roles in systemic and mucosal immunity. In the current study, in rainbow trout, we have cloned the heavy chain (Igτ) genes of a secretory form of IgT2 as well as the membrane and secretory forms of a third IgT subclass, termed IgT3. Conserved cysteine and tryptophan residues that are crucial for the folding of the immunoglobulin domain as well as hydrophobic and hydrophilic residues within CART motif were identified in all IgT subclasses. Through analysis of the rainbow trout genome assembly, Igτ3 gene was found localized upstream of Igτ1 gene, while Igτ2 gene situated on another scaffold. At the transcriptional level, Igτ1 was mainly expressed in both systemic and mucosal lymphoid tissues, while Igτ2 was largely expressed in systemic lymphoid organs. After LPS and poly (I:C) treatment, Igτ1 and Igτ2 genes exhibited different expression profiles. Interestingly the transcriptional level of Igτ3 was negligible, although its protein product could be identified in trout serum. Importantly, a previously reported monoclonal antibody directed against trout IgT1 was able to recognize IgT2 and IgT3. These data demonstrate that there exist three subclasses of IgT in rainbow trout, and that their heavy chain genes display different expression patterns during stimulation. Overall, our data reflect the diversity and complexity of immunoglobulin in trout, thus provide a better understanding of the IgT system in the immune response of teleost fish.


Assuntos
Imunidade Humoral , Imunidade nas Mucosas , Imunoglobulinas/metabolismo , Tecido Linfoide/metabolismo , Oncorhynchus mykiss/imunologia , Animais , Diversidade de Anticorpos , Células Cultivadas , Clonagem Molecular , Imunoglobulinas/genética , Lipopolissacarídeos/imunologia , Proteínas do Tecido Nervoso/genética , Poli I-C/imunologia , Domínios Proteicos/genética , Dobramento de Proteína , Transcriptoma
7.
Chem Commun (Camb) ; 52(99): 14274-14277, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27878148

RESUMO

A photo/chemo dually interconvertible system was constructed through the supramolecular assembly of azobenzene-diphenylalanine (Azo-FF) with α-cyclodextrin. The resultant chiral nanohelix was able to interconvert into a nanosquare upon irradiation at different wavelengths, but into a nanofiber upon changing solvent polarity, which provides a feasible way to achieve highly ordered nanostructures with various morphologies, dimensions and chiralities.

8.
Sci Rep ; 6: 36048, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808112

RESUMO

The gut-associated lymphoid tissue, connected with liver via bile and blood, constructs a local immune environment of both defense and tolerance. The gut-liver immunity has been well-studied in mammals, yet in fish remains largely unknown, even though enteritis as well as liver and gallbladder syndrome emerged as a limitation in aquaculture. In this study, we performed integrative bioinformatic analysis for both transcriptomic (gut and liver) and proteomic (intestinal mucus and bile) data, in both healthy and infected tilapias. We found more categories of immune transcripts in gut than liver, as well as more adaptive immune in gut meanwhile more innate in liver. Interestingly reduced differential immune transcripts between gut and liver upon inflammation were also revealed. In addition, more immune proteins in bile than intestinal mucus were identified. And bile probably providing immune effectors to intestinal mucus upon inflammation was deduced. Specifically, many key immune transcripts in gut or liver as well as key immune proteins in mucus or bile were demonstrated. Accordingly, we proposed a hypothesized profile of fish gut-liver immunity, during either homeostasis or inflammation. Current data suggested that fish gut and liver may collaborate immunologically while keep homeostasis using own strategies, including potential unique mechanisms.


Assuntos
Peixes/imunologia , Trato Gastrointestinal/imunologia , Homeostase , Imunidade nas Mucosas , Inflamação/genética , Fígado/imunologia , Proteoma/metabolismo , Transcriptoma/genética , Animais , Bile/metabolismo , Peixes/genética , Regulação da Expressão Gênica , Biblioteca Gênica , Ontologia Genética , Inflamação/imunologia , Inflamação/metabolismo , Muco/metabolismo , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Dev Comp Immunol ; 61: 169-79, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27057962

RESUMO

Immunoglobulin light chain (IgL) is necessary for the assembly of an Ig molecule, which plays important roles in the immune response. IgL genes were identified in various teleost species, but the basic functions of different IgL isotypes and the preferential combination between IgL and IgH (Ig heavy chain) isotypes remain unclear. In the current study, by EST database searching and cDNA cloning in rainbow trout, 8 IgL sequences were obtained, which could be classified into the IgLκF, IgLκG, IgLσ and IgLλ isotypes, respectively. Trout IgL isotypes were highly expressed in the immune-related tissues, and participated in the immune responses in spleen and gut by stimulation with LPS and poly (I:C). The results of FACS and LC-MS/MS indicated that the IgLκG and IgLσ isotypes preferentially bonded with the heavy chains of IgM and IgT, respectively, in trout B cells and serum. In addition, the genomic organization of trout IgL isotypes and the utilization of recombination signal sequences were studied.


Assuntos
Linfócitos B/imunologia , Proteínas de Peixes/genética , Peixes/imunologia , Cadeias Pesadas de Imunoglobulinas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Intestinos/imunologia , Baço/imunologia , Animais , Células Cultivadas , Dimerização , Proteínas de Peixes/metabolismo , Cadeias Pesadas de Imunoglobulinas/genética , Isotipos de Imunoglobulinas , Cadeias Leves de Imunoglobulina/genética , Lipopolissacarídeos/imunologia , Poli I-C/imunologia , Ligação Proteica , Truta
10.
J Phys Chem B ; 120(16): 3932-40, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-27046098

RESUMO

The push-pull molecules with an intramolecular charge transfer from donor to acceptor sides upon excitation exhibit a wide variety of biological and electronic activities, as exemplified by the in vivo fluorescence imaging probes for amyloid fibrils in the diagnosis and treatment of amyloid diseases. Interestingly, the structurally much simpler bis(4,8-disulfonato-1,5-naphtho)-32-crown-8 (DNC), in keen contrast to the conventional macrocyclic receptors, was found to dramatically enhance the fluorescence of twisted intramolecular charge-transfer molecules possessing various benzothiazolium and stilbazolium fluorophores upon complexation. Spectroscopic and microcalorimetric titrations jointly demonstrated the complex structures and the interactions that promote the extremely strong complexation, revealing that the binding affinity in these artificial host-guest pairs could reach up to a nearly 10(7) M(-1) order of magnitude in water, and the sandwich-type complexation is driven by electrostatic, hydrophobic, π-stacking, and hydrogen-bonding interactions. Quantum chemical calculations on free molecules and their DNC-bound species in both the ground and excited states elucidated that the encapsulation by DNC could greatly deter the central single and double chemical bonds from free intramolecular rotation in the singlet excited state, thus leading to the unique and unprecedented fluorescence enhancement upon sandwich-type complexation. This complexation-induced structural reorganization mechanism may also apply to the binding of other small-molecule ligands by functional receptors and contribute to the molecular-level understanding of the receptor-ligand interactions in many biology-related systems.


Assuntos
Amiloide/química , Fluorescência , Receptores Artificiais/química , Tiazóis/química , Benzotiazóis , Corantes Fluorescentes/química , Ligantes , Conformação Molecular , Teoria Quântica
11.
Fish Shellfish Immunol ; 52: 74-84, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26988285

RESUMO

Bacillus subtilis is widely used as probiotic species in aquaculture for water quality control, growth promoting, or immunity enhancing. The aim of this study is to find novel B. subtilis strains from fish as potential probiotics for aquaculture. Eleven B. subtilis isolates derived from the intestinal tract of grass carp were identified by gene sequencing and biochemical tests. These isolates were classified into 4 groups, and the representatives (GC-5, GC-6, GC-21 and GC-22) of each group were further investigated for antibiotic susceptibility, sporulation rate, biofilm formation, activity against pathogenic bacteria, resistance to stress conditions of intestinal tract (high percentage of bile and low pH) and high temperature, which are important for probiotics to be used as feed additives. Additionally, the adhesion properties of the 4 characterized strains were assessed using Caco-2 cell and gut mucus models. The results showed that the 4 strains differed in their capacities to adhere to intestinal epithelial cells and mucus. Furthermore, the strains GC-21 and GC-22 up-regulated the expression levels of IL-10 and TGF-ß but down-regulated IL-1ß, suggesting their potential anti-inflammatory abilities. Based on physiological properties of the 4 characterized B. subtilis strains, one or more strains may have potential to be used as probiotics in aquaculture.


Assuntos
Ração Animal/microbiologia , Bacillus subtilis/isolamento & purificação , Carpas/microbiologia , Carpas/fisiologia , Probióticos/isolamento & purificação , Ração Animal/análise , Animais , Aquicultura , Carpas/imunologia , Dieta/veterinária , Imunidade Inata , Intestinos/imunologia , Intestinos/microbiologia
12.
J Immunol ; 196(9): 3744-53, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26994222

RESUMO

For a virus to replicate efficiently, it must try and inhibit host IFN expression because IFN is an important host defense at early stages after viral infection. For aquatic viruses, the mechanisms used to escape the hosts IFN system are still unclear. In this study, we show that the N protein of spring viremia of carp virus (SVCV) inhibits zebrafish IFNφ1 production by degrading the mitochondrial antiviral signaling protein (MAVS). First, the upregulation of IFNφ1 promoter activity stimulated by polyinosinic:polycytidylic acid, retinoic acid-inducible gene I (RIG-I) or MAVS was suppressed by the SVCV infection. However, the upregulation by the downstream factor of the RIG-I-like receptor signaling pathway, TANK-binding kinase 1, was not affected. Notably, at the protein level, MAVS decreased remarkably when cells were infected with SVCV. Second, consistent with the result of the SVCV infection, overexpression of the N protein of SVCV blocked the IFNφ1 transcription activated by MAVS and downregulated MAVS expression at the protein level but not at the mRNA level. Further analysis demonstrated that the N protein targeted MAVS for K48-linked ubiquitination, which promoted the degradation of MAVS. These data indicated that fish MAVS could be degraded by the N protein of SVCV through the ubiquitin-proteasome pathway. To our knowledge, this is the first article of a fish RIG-I-like receptor pathway interfered by an aquatic virus in an ubiquitin-proteasome manner, suggesting that immune evasion of a virus also exists in lower vertebrates.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína DEAD-box 58/metabolismo , Células Epiteliais/fisiologia , Mitocôndrias/metabolismo , Proteínas do Nucleocapsídeo/imunologia , Infecções por Rhabdoviridae/imunologia , Rhabdoviridae/imunologia , Proteínas de Peixe-Zebra/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Carpas , Linhagem Celular , Células Epiteliais/virologia , Evasão da Resposta Imune , Imunidade , Interferons/metabolismo , Transdução de Sinais , Ativação Transcricional , Ubiquitinação , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
13.
Fish Shellfish Immunol ; 46(2): 765-77, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26277647

RESUMO

The immune role of NCAMs has been revealed in mammals, yet there is no such report in fish. Hence, we analyzed the molecular characterizations and immune-associated expression patterns of NCAMs in mandarin fish. Three NCAM members, named mfNCAM1a, mfNCAM1b and mfNCAM2, were identified. Among the cDNA sequences of mfNCAMs, AU-rich elements in the 3' UTRs of mfNCAM1b and mfNCAM2 as well as VASE sequences in the fourth Ig-like domain-encoding regions of mfNCAM1a and mfNCAM1b were discovered. Moreover, the syntenic analysis suggested that the duplication of NCAM1 is fish-specific. At mRNA and protein levels, the expression analyses revealed that mfNCAMs existed in both systemic and mucosal immune tissues, and located within lymphoid cells. Upon stimulated either by LPS or poly I:C, the expression level of mfNCAM1a was significantly up-regulated in head kidney, spleen, liver, and gut, whereas mfNCAM1b only in head kidney and liver, and mfNCAM2 only in liver. Additionally, the cells coexpressed mfNCAM1 and mfNCCRP-1 might imply the equivalents to mammalian NK cells. Our finding firstly demonstrates the member-specific immune-related tissue expression pattern and immune activity for fish NCAMs. Current data indicate that mfNCAM2 has little immune activity, while the immune activity of mfNCAM1a exists in more tissues than mfNCAM1b, and mfNCAM1a may tend to respond more actively to viral while mfNCAM1b to bacterial stimulants. Additionally, NCAM1b should be a fish-specific member with unique immune function, judging from its different expression pattern, immune activity as well as phylogenetic relationship to mfNCAM1a.


Assuntos
Proteínas de Peixes/genética , Moléculas de Adesão de Célula Nervosa/genética , Perciformes/genética , Perciformes/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Imuno-Histoquímica/veterinária , Hibridização In Situ/veterinária , Lipopolissacarídeos/farmacologia , Dados de Sequência Molecular , Moléculas de Adesão de Célula Nervosa/química , Moléculas de Adesão de Célula Nervosa/metabolismo , Especificidade de Órgãos , Filogenia , Poli I-C/farmacologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Alinhamento de Sequência/veterinária , Regulação para Cima
14.
J Immunol ; 194(10): 4974-87, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25876762

RESUMO

Cathelicidin antimicrobial peptides (CAMPs) represent a crucial component of the innate immune system in vertebrates. Although widely studied in mammals, little is known about the structure and function of fish CAMPs. Further to the previous findings, two more cathelicidin genes and multiple transcripts from rainbow trout were identified in the present study. Interestingly, we found that trout have evolved energy-saving forms of cathelicidins with the total deletion of the characteristic cathelin-like domain. Sequence analysis revealed that salmonid CAMPs have formed a special class of antimicrobial peptides in vertebrates with three distinctive hallmarks: the N terminus is intensified by positive charges, the central region consists of repetitive motifs based on RPGGGS, and the C terminus is lowly charged. Immunofluorescence localization of trout CAMPs demonstrated that these peptides expressed mainly at the mucosal layer of gut. Meanwhile, signals around sinusoids were also detected in head kidney. Moreover, the biological activities of trout CAMPs were proved to be mediated by the N terminus. Additionally, the repetitive motifs characteristically existing in Salmonidae increased the structural flexibilities of peptides and further increased the antibacterial and IL-8-stimulating activities. Unlike most α helical and cytotoxic mammalian CAMPs, trout CAMPs, mainly consisting of ß-sheet and random coil, exhibited no cytotoxic activities. The distinctive structural features of trout CAMPs provide new insights into the understanding of the evolution of CAMPs in vertebrates. Moreover, the high bacterial membrane selectivity of trout CAMPs will help to design excellent peptide antibiotics.


Assuntos
Catelicidinas/genética , Catelicidinas/imunologia , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Sequência de Aminoácidos , Animais , Western Blotting , Imunofluorescência , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
15.
Chem Commun (Camb) ; 51(34): 7329-32, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25819834

RESUMO

Nanorod-like supramolecular aggregates are fabricated by the self-assembly of the amphiphilic [2]pseudorotaxane, which can be dissociated and rebuilt by the alternating UV/vis irradiation.

16.
J Nat Med ; 68(2): 448-54, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24385232

RESUMO

In this work, an approach based on antioxidant fingerprint-efficacy relationships and TLC bioautography assay was developed for quality evaluation of traditional Chinese medicine (TCM). First, chemical fingerprints of 20 batches of different sources of Rubia cordifolia were established by HPLC. The antioxidant activities of these samples were evaluated by 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. Then, five active components from fingerprint peaks were determined by both multiple correlation analysis and TLC bioautography assay. Similarity analysis and hierarchical clustering analysis (HCA) based on these active peaks were chosen to evaluate the quality of R. cordifolia from different sources. The samples with similarities below 0.9 had poorer antioxidant activities and those having stronger activities fell into the same cluster in HCA. Finally, five batches of commercial samples were processed in the same way to verify the feasibility of this method. The results suggested that chemical fingerprinting combined with similarity analysis based on fingerprint-efficacy relationship and TLC bioautography could evaluate the antioxidant activity of R. cordifolia from various sources. The established technique would also provide an easy method of evaluating the quality of other TCMs.


Assuntos
Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Delgada/métodos , Rubia/química , Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/normas
17.
PLoS One ; 6(4): e18681, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21541342

RESUMO

In addition to a fast activating and immediately inactivating inward sodium current, many types of excitable cells possess a noninactivating or slowly inactivating component: the persistent sodium current (I(NaP)). The I(NaP) is found in normal primary sensory neurons where it is mediated by tetrodotoxin-sensitive sodium channels. The dorsal root ganglion (DRG) is the gateway for ectopic impulses that originate in pathological pain signals from the periphery. However, the role of I(NaP) in DRG neurons remains unclear, particularly in neuropathic pain states. Using in vivo recordings from single medium- and large-diameter fibers isolated from the compressed DRG in Sprague-Dawley rats, we show that local application of riluzole, which blocks the I(NaP), also inhibits the spontaneous activity of A-type DRG neurons in a dose-dependent manner. Significantly, riluzole also abolished subthreshold membrane potential oscillations (SMPOs), although DRG neurons still responded to intracellular current injection with a single full-sized spike. In addition, the I(NaP) was enhanced in medium- and large-sized neurons of the compressed DRG, while bath-applied riluzole significantly inhibited the I(NaP) without affecting the transient sodium current (I(NaT)). Taken together, these results demonstrate for the first time that the I(NaP) blocker riluzole selectively inhibits I(NaP) and thereby blocks SMPOs and the ectopic spontaneous activity of injured A-type DRG neurons. This suggests that the I(NaP) of DRG neurons is a potential target for treating neuropathic pain at the peripheral level.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/patologia , Ativação do Canal Iônico/efeitos dos fármacos , Neurônios/patologia , Riluzol/farmacologia , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/metabolismo , Animais , Gânglios Espinais/fisiopatologia , Hiperalgesia/complicações , Hiperalgesia/patologia , Hiperalgesia/fisiopatologia , Potenciais da Membrana/efeitos dos fármacos , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/patologia , Neurônios/efeitos dos fármacos , Radiculopatia/complicações , Radiculopatia/patologia , Radiculopatia/fisiopatologia , Ratos , Ratos Sprague-Dawley
18.
Neurosci Bull ; 27(1): 61-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21270905

RESUMO

Animals and humans share similar mechanisms of pain detection and similar brain areas involved in pain processing. Also, they show similar pain behaviors, such as reflexed sensation to nociceptive stimuli. Pain is often described in sensory discrimination (algosity) and affective motivation (unpleasantness) dimensions. Both basic and clinical findings indicate that individuals with chronic pain usually suffer more from pain-associated affective disturbances than from the actual pain sensations per se. Although the neural systems responsible for the sensory component of pain have been studied extensively, the neural mechanisms underlying negative affective component are not well understood. This is partly due to the relative paucity of animal paradigms for reliable examination of each component of pain. In humans, the experience of pain and suffering can be reported by language, while in animals, pain can only be inferred through physical and behavioral reactions. Animal behaviors, cognitive psychology and functional brain imaging have made it possible to assess pain affection and pain memory in animals. Animals subjected to either neuropathic injury or inflammatory insult display significant conditioned place aversion to a pain-paired environment in behaviors. The present review aims to summarize the common methods of affective unpleasantness assessment in rats.


Assuntos
Comportamento Animal/fisiologia , Modelos Animais de Doenças , Transtornos do Humor/psicologia , Medição da Dor/métodos , Dor/psicologia , Animais , Humanos , Transtornos do Humor/etiologia , Dor/complicações , Dor/fisiopatologia , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA