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1.
Artigo em Inglês | MEDLINE | ID: mdl-38568198

RESUMO

Two Gram-negative, non-spore-forming, non-motile, non-flagellated bacteria, designated strains D6T and DH64T, were isolated from surface water of the Pacific Ocean. For strain D6T, growth occurred at 10-40 °C, pH 5.5-9.0 and in the presence of 0-8.0 % NaCl (w/v). For strain DH64T, growth occurred at 10-40 °C, pH 5.5-8.5 and in the presence of 0.5-8.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains D6T and DH64T both belonged to the genera Flagellimonas, with the highest sequence identities to Flagellimonas taeanensis JCM 17757T (98.2 %) and Flagellimonas marinaquae JCM 11811T (98.6 %), respectively. The 16S rRNA gene sequence identity between strains D6T and DH64T was 95.9 %. The average amino acid identity and digital DNA-DNA hybridization values between the two strains and the nearest phylogenetic neighbours were 66.7-93.3 % and 16.1-38.5 %, respectively. The major respiratory quinone of both strains was menaquinone-6. The major polar lipid was phosphatidylethanolamine. The major fatty acids were identified similarly as iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. The genomic G+C contents of strains D6T and DH64T were determined to be 45.5 and 42.6 mol%, respectively. The combined genotypic and phenotypic data show that the strains represent two novel species within genera Flagellimonas, for which the names Flagellimonas baculiformis sp. nov. and Flagellimonas crocea sp. nov. are proposed, with type strains D6T (=MCCC M28982T=KCTC 92604T) and DH64T (=MCCC M28986T=KCTC 92975T).


Assuntos
Ácidos Graxos , Cloreto de Sódio , Oceano Pacífico , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Água do Mar
2.
Zhen Ci Yan Jiu ; 48(11): 1117-1124, 2023 Nov 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37984909

RESUMO

OBJECTIVES: To observe the application value of MR T2 mapping for evaluating the effect of warm acupuncture-moxibustion on articular cartilage degeneration, and to observe the relationship between T2 value and expression of matrix metalloproteinases (MMP)-1 and MMP-13 of chondrocytes in rabbits with early knee osteoarthritis (KOA). METHODS: Thirty male New Zealand rabbits were randomly divided into blank control, KOA model and warm acupuncture-moxibustion groups, with 10 rabbits in each group. The early KOA model was established by right hind limb tubular plaster extension fixation method for 2 weeks. The rabbits of the warm acupuncture-moxibustion group received warm acupuncture-moxibustion stimulation at "Heding"(EX-LE2), "Neixiyan"(EX-LE4), "Waixiyan" (EX-LE5) and"Zusanli"(ST36) on the right hind limb for 15 min, once a day for 2 weeks. After intervention, MR T2 mapping of the right knee joint was performed in each group. The H.E. staining was used to evaluate the histopathological changes of cartilage, followed by giving a score according to the standards of Mankin scoring. The TUNEL method was used to analyze the apoptosis state of chondrocytes, and the positive expressions of MMP-1 and MMP-13 in the articular cartilage were detected by immunohistochemical staining. RESULTS: Compared with the blank control group, the Mankin score, chondrocyte apoptosis index, T2 value and the positive expressions of MMP-1 and MMP-13 in the cartilage tissue were significantly increased in the model group (P<0.01). Compared with the model group, the Mankin score, chondrocyte apoptosis index, T2 value and the positive expressions of MMP-1 and MMP-13 in the cartilage tissue were markedly decreased in the warm acupuncture-moxibustion group (P<0.01). The T2 value was positively correlated with the expression levels of MMP-1 and MMP-13 (P<0.01). H.E. staining showed disordered arrangement of chondrocytes and thinner cartilage layer in the model group, and a clear and relative ordered arrangement of chondrocyte in the warm acupuncture-moxibustion group. CONCLUSIONS: Warm acupuncture-moxibustion can reduce the T2 value of articular cartilage in early KOA rabbits, which is positively correlated with the decreased expression of MMP-1 and MMP-13 in the extracellular matrix of cartilage. The MR T2 mapping has certain value in evaluating the effect of warm acupuncture-moxibustion on KOA rabbits with early cartilage degeneration.


Assuntos
Terapia por Acupuntura , Cartilagem Articular , Moxibustão , Osteoartrite do Joelho , Animais , Masculino , Coelhos , Terapia por Acupuntura/métodos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/terapia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37000637

RESUMO

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, designated C281T, was isolated from seawater sampled at the Marshallese seamount chain. Results of 16S rRNA gene analysis revealed that strain C281T was most closely related to Membranihabitans marinus CZ-AZ5T with 92.7 % sequence similarity. Phylogenetic analysis indicated that the new isolate represented a novel species by forming a distinctive lineage within the family Saprospiraceae. The DNA G+C content of strain C281T was 38.4 mol%. The genome sizes of strain C281T and the reference strain M. marinus CZ-AZ5T were 5 962 917 and 5 395 999 bp, respectively. The average nucleotide identity and in silico DNA-DNA hybridization values between strains C281T and M. marinus CZ-AZ5T were found to be low (69.3 and 17.6 %, respectively). Different functional genes were found in the genome of strain C281T, such as CZC CBA, polysaccharide utilization loci and linear azol(in)e-containing peptide cluster coding genes. The NaCl range for growth was 0.5-15.0 %. Positive results were obtained for hydrolysis of Tween 60 and urease. MK-7 was the sole respiratory quinone. The major fatty acids were C16 : 1 ω6c and/or C16 : 1 ω7c, iso-C15 : 0 and iso-C15 : 1 F. The major polar lipids of strain C281T were phosphatidylethanolamine, phosphatidylglycerol, two unidentified lipids and five unidentified glycolipids. On the basis of its taxonomic characteristics, the isolate represents a novel species of the genus Membranihabitans, for which the name Membranihabitans maritimus sp. nov. (type strain C281T=KCTC 92171T=MCCC M27001T) is proposed.


Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Água do Mar/microbiologia
4.
J Tradit Chin Med ; 41(6): 959-967, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34939393

RESUMO

OBJECTIVE: To explore the molecular mechanism of warming moxibustion (WM) in knee osteoarthritis (KOA). METHODS: The knee joints of 40 New Zealand rabbits were placed in a plaster cast in an extended position to establish a KOA model. The animals were randomly divided into four groups: the control group, model group, WM group, and diclofenac (DF) group. Hematoxylin-eosin staining and the modified Mankin score were applied to evaluate the histopathological changes. Chondrocyte apoptosis was determined by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Western blotting and real-time quantitative polymerase chain reaction were performed to measure the expression of interleukin-1α (IL-1ß), prostaglandin E receptor 3 (PTGER3), a disintegrin-like and metalloproteinase with thrombospondin type-1 motifs-5 (ADAMTS-5), matrix metalloproteinase-13 (MMP-13), and C-terminal telopeptides of collagen type II (CTX-II) in cartilage tissues of the different groups. The concentrations of IL-1ß, PTGER3, and CTX-II in serum were detected by the enzyme-linked immunosorbent assay. RESULTS: Rabbits with KOA in the WM and DF groups showed significantly reduced cartilage erosion and Mankin scores, compared with the untreated rabbits. The number of TUNEL-positive cells observed in the WM group was much fewer than that in the model group. The expression of PTGER3, MMP-13, CTX-II IL-1ß, and ADAMTS-5 in cartilage tissues was remarkably downregulated following therapy with WM and DF. Moreover, a marked reduction was observed in the serum levels of IL-1ß, PTGER3, and CTX-II in the WM and DF groups. CONCLUSION: WM exerts favorable therapeutic effects on articular injuries of KOA by regulating the expression of inflammatory and cartilage degradation-related cytokines.


Assuntos
Cartilagem Articular , Moxibustão , Osteoartrite do Joelho , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Inflamação , Articulação do Joelho , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/terapia , Coelhos
5.
Zhen Ci Yan Jiu ; 46(2): 123-8, 2021 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-33788433

RESUMO

OBJECTIVE: To observe the effect of warm needle with moxibustion (WNM) on morphological changes of articular cartilage and subchondral bone tissues in knee osteoarthritis (KOA) rabbits, so as to explore whether WNM intervention can delay the development of KOA. METHODS: Forty male New Zealand rabbits were randomly divided into blank control, model, WNM and medication (Alendronate sodium) groups, with 10 rabbits in each group. A KOA model was established by immobilizing the right hind limb of rabbits with orthopedic casting tape for 6 weeks. The rabbits of the WNM group received WNM stimulation at "Neixiyan"(EX-LE4) "Waixiyan"(ST35) and "Heding"(EX-LE2) for 15 min, once a day for 4 weeks and those of the medication group received gavage of Alendronate sodium (150 µg·kg-1·d-1) once a day for 4 weeks. X-ray examination and magnetic resonance imaging (MRI) scanning were performed to observe the structure of the knee joints. Outcomes of X-ray examination were used to assess the degree of bone hyperplasia and joint space stenosis which were scaled according to Kellgren and Lawrence (K-L) standards, and those of MRI used to evaluate the degree of cartilage damage and bone marrow edema degrees which were respectively scored according to Recht scaling standards and semi-quantitative whole-organ MRI score (WORMS). Histopathological changes (degeneration degrees) of the articular cartilage were observed after H.E. staining, and given Mankin score. The ultrastructure of the cartilage surface and chondrocytes was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. RESULTS: Compared with the blank control group, the K-L grade, Recht grade, WORMS and Mankin score of the model group were significantly increased (P<0.05,P<0.01). After the intervention and in comparison with the model group, the K-L grade, Recht grade, WORMS and Mankin score of both WNM and medication groups were significantly decreased (P<0.05,P<0.01). Results of SEM showed severe defect, bulge and uneven surface of the cartilage with irregular growth and regeneration, and those of TEM showed degeneration and swelling of chondrocytes, margination of endonuclear chromatin, reduction in the number of organelles with disordered arrangement, extreme expansion of endoplasmic reticulum with detachment of the ribosome, unclear mitochondria, and disordered distribution of collagen fibers in the extracellular matrix in the model group, which was relatively milder in both the WNM and medication groups. Compared with the medication group, the Mankin score in the WNM group was evidently lower (P<0.05). CONCLUSION: WNM can effectively slow down the degeneration of cartilage and subchondral bone of KOA rabbits, delay the development of KOA.


Assuntos
Cartilagem Articular , Moxibustão , Osteoartrite do Joelho , Animais , Osso e Ossos , Articulação do Joelho , Masculino , Osteoartrite do Joelho/terapia , Coelhos
6.
Appl Opt ; 60(7): 2100-2108, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690304

RESUMO

Intelligent photonic circuits (IPCs) tuned with an appropriate phase-shift vector could enable a photonic intelligent matrix possibly implemented in multiple neural layers for a task-oriented topologies. A photonic Mach-Zehnder Interferometer (MZI) is a fundamental photonic component in IPCs, whose matrix representation could be broadcasted into an arbitrary matrix that is equipped with an optimized phase-shift vector. The initialized MZIs' phases are tentatively probed between analytical elements and a digital weight matrix that is learned from samples with efficient compatible learning for complex-valued neural networks. Nonlinear least squares is utilized to formulate a phase determination system to refine the optimal phase-shift solutions. The robustness of phase determination system for photonic neural networks is discussed in detail. For a preliminary implementation, a basic 4×4 intelligent photonic neural network is utilized to verify the proof of concept on phase-shift determination in IPC through numerical experiments.

7.
Aging (Albany NY) ; 10(5): 988-999, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29746255

RESUMO

Glioblastoma (GBM) is the most commonly diagnosed solid tumor outside the central nervous system. However, genetic factors underlying GBM remain largely unclear. Previous studies indicated that Glial fibrillary acidic protein (GFAP) might play an important role in the aggressiveness of GBM and also contributed to its poor overall survival. The present study aims to test (1) the associations between GFAP single nucleotide polymorphisms (SNPs) and GBM cells chemoresistance and metastasis, and (2) the molecular mechanism accounting for their effects. Four tagging SNPs of GFAP were initially genotyped in 667 subjects and the significant SNP was further analyzed via online bioinformatical tools. SNP rs11558961 was found to be significantly associated with GBM susceptibility. It was predicted to influence microRNA(miR)-139 binding to 3'UTR of GFAP gene. In functional experiments, we found that cells transfected with rs11558961 G-allele constructs had lower baseline luciferase activities and were more responsive to miR-139 changes, compared to C-allele constructs. Moreover, rs11558961 C>G variant reduced the chemoresistance of GBM cells and migration capability. In conclusion, rs11558961 might influence the chemoresistance and progression of GBM cells via promoting the binding of miR-139, ultimately decrease the susceptibility of GBM. This investigation will shed light on the optimizing for clinical trial design and individualizing of therapeutic plans.


Assuntos
Neoplasias Encefálicas/genética , Predisposição Genética para Doença/genética , Proteína Glial Fibrilar Ácida/genética , Glioblastoma/genética , MicroRNAs/metabolismo , Adulto , Idoso , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
8.
J Asian Nat Prod Res ; 17(9): 908-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25978098

RESUMO

Two new triterpenoid saponins (1 and 2) were isolated from the stems of Ilex cornuta, along with two known triterpenoids (3 and 4). The structures of compounds 1 and 2 were determined as ursane-12,19-diene-28-oic acid 3ß-O-ß-D-glucuronopyranoside-6-O-methyl ester (1), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-O-ß-D-glucopyranosyl ester (2), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds 1-4 were tested against H(2)O(2)-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.


Assuntos
Ilex/química , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Miócitos Cardíacos/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Saponinas/química , Estereoisomerismo , Triterpenos/química
9.
Med Chem ; 8(4): 683-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22530908

RESUMO

The synthesis and biological evaluation of hybrid opioids consisting of Naloxone or Naltrexone and a partial opioid peptide are described. These compounds were synthesized in a homogeneous solution as well as in solid phase. A hydrazone linkage was employed to connect the alkaloids to the tetrapeptides. In synthesizing the peptides some non-traditional methods, which provided excellent results, were explored. The solid phase synthesis was achieved by anchoring the Fmoc-Phe to the 2-chlorotrityl resin, followed by stepwise addition of two Fmoc-Gly units. Each addition step preceded by standard piperidine removal of the Fmoc from the prior amino acid (AA) residue. The final AA, Tyr, was added as its Boc derivative. The Boc-tetrapeptide was then separated from the resin with a TFE/AcOH/CH(2)Cl(2) mixture. In the solution synthesis, each peptide elongation step was accomplished by one-pot removal of the Fmoc from the prior AA residue and addition of the next Fmoc-AA. TBAF-thiol was used to cleanly remove the Fmoc, before adding the next Fmoc-AA in the presence of DIPEA and TBTU. All prepared hybrid ligands exhibited high affinities toward all three opioid receptors; moderate preferences for κ and µ receptors over δ receptor were observed. [(35)S]GTPγS binding assays indicated that these hybrid opioids are δ and µ antagonists but partial κ agonist.


Assuntos
Analgésicos Opioides , Naloxona/síntese química , Naloxona/farmacologia , Naltrexona/síntese química , Naltrexona/farmacologia , Sequência de Aminoácidos , Analgésicos Opioides/síntese química , Analgésicos Opioides/química , Analgésicos Opioides/farmacologia , Sítios de Ligação , Concentração Inibidora 50 , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Estrutura Molecular , Antagonistas de Entorpecentes/síntese química , Antagonistas de Entorpecentes/farmacologia , Peptídeos/química , Peptídeos/genética , Ligação Proteica/efeitos dos fármacos , Receptores Opioides/química , Técnicas de Síntese em Fase Sólida
10.
Comput Biol Chem ; 29(2): 95-100, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15833437

RESUMO

In recent years, the poly-L-proline type II (PPII) conformation has gained more and more importance. This structure plays vital roles in many biological processes. But few studies have been made to predict PPII secondary structures computationally. The support vector machine (SVM) represents a new approach to supervised pattern classification and has been successfully applied to a wide range of pattern recognition problems. In this paper, we present a SVM prediction method of PPII conformation based on local sequence. The overall accuracy for both the independent testing set and estimate of jackknife testing reached approximately 70%. Matthew's correlation coefficient (MCC) could reach 0.4. By comparing the results of training and testing datasets with different sequence identities, we suggest that the performance of this method correlates with the sequence identity of dataset. The parameter of SVM kernel function was an important factor to the performance of this method. The propensities of residues located at different positions were also analyzed. By computing Z-scores, we found that P and G were the two most important residues to PPII structure conformation.


Assuntos
Bases de Dados de Proteínas , Reconhecimento Automatizado de Padrão , Peptídeos/química , Biologia Computacional , Conformação Proteica
11.
FEBS Lett ; 576(3): 336-8, 2004 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-15498558

RESUMO

Proline is a special imino acid in protein and the isomerization of the prolyl peptide bond has notable biological significance and influences the final structure of protein greatly, so the correlation between proline synonymous codon usage and local amino acid, the correlation between proline synonymous codon usage and the isomerization of the prolyl peptide bond were both investigated in the Escherichia coli genome by using a novel method based on information theory. The results show that in peptide chain, the residue at the first position C-terminal influences the usage of proline synonymous codon greatly and proline synonymous codons contain some factors influencing the isomerization of the prolyl peptide bond.


Assuntos
Códon/genética , Escherichia coli/genética , Prolina/genética , Genoma Bacteriano , Peptídeos/química , Conformação Proteica
12.
Biochem Biophys Res Commun ; 318(1): 142-7, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15110765

RESUMO

In this paper, a novel approach has been introduced to predict the disulfide-bonding state of cysteines in proteins by means of a linear discriminator based on their dipeptide composition. The prediction is performed with a newly enlarged dataset with 8114 cysteine-containing segments extracted from 1856 non-homologous proteins of well-resolved three-dimensional structures. The oxidation of cysteines exhibits obvious cooperativity: almost all cysteines in disulfide-bond-containing proteins are in the oxidized form. This cooperativity can be well described by protein's dipeptide composition, based on which the prediction accuracy of the oxidation form of cysteines scores as high as 89.1% and 85.2%, when measured on cysteine and protein basis using the rigorous jack-knife procedure, respectively. The result demonstrates the applicability of this new relatively simple method and provides superior prediction performance compared with existing methods for the prediction of the oxidation states of cysteines in proteins.


Assuntos
Cisteína/química , Dipeptídeos/química , Dissulfetos/química , Modelos Químicos , Sequência de Aminoácidos , Bases de Dados de Proteínas , Oxirredução
13.
Planta Med ; 68(8): 719-22, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12221595

RESUMO

Two new gamma-lactones, saccopetrin A (1) and saccopetrin B (2), together with 10 known compounds have been isolated from the roots of Saccopetalum prolificum. Their structures were established by spectroscopic and chemical methods. The absolute configuration of 1 was determined by chemical transformation and the Mosher method. Cytotoxic activities were evaluated against several different cell lines. Compound 2 exhibited stronger cytotoxic activities than 1 against KB and HCT-8 cell lines at a concentration of 10(-5) mol/L.


Assuntos
Annonaceae/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Quassinas/isolamento & purificação , Quassinas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/efeitos adversos , Lactonas/química , Estrutura Molecular , Plantas Medicinais/química , Quassinas/química , Células Tumorais Cultivadas
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