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1.
Marine sponges contain dense and diverse microbial communities, which are renowned as a source of bioactive metabolites. The biological activities of sponge-microbe natural products span a broad spectrum, from antibacterial and antifungal to antitumor and antiviral applications. However, the potential of sponge-derived compounds has not been fully realized, due largely to the acknowledged “supply issue.” Most bacteria from environmental samples have resisted cultivation on artificial growth media, and cultivation of sponge-associated bacteria has been a major focus in the search for novel marine natural products. One approach to isolate so-called “uncultivable” microorganisms from different environments is the diffusion growth chamber method. Here, we describe the first application of diffusion growth chambers for the isolation of cultivable and previously uncultivated bacteria from sponges. The study was conducted by implanting diffusion growth chambers in the tissue of Rhabdastrella globostellata reef sponges. In total, 255 16S rRNA gene sequences were obtained, with phylogenetic analyses revealing their affiliations with the Alpha- and Gammaproteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes. Fifteen sequences represented previously uncultivated bacteria belonging to the Bacteroidetes and Proteobacteria (Alpha and Gamma classes). Our results indicate that the diffusion growth chamber approach can be successfully applied in a natural, living marine environment such as sponges.  相似文献   

2.
Sponges are important components of marine benthic communities. High microbial abundance sponges host a large diversity of associated microbial assemblages. However, the dynamics of such assemblages are still poorly known. In this study, we investigated whether bacterial assemblages present in Spongia lamella remained constant or changed as a function of the environment and life cycle. Sponges were collected in multiple locations and at different times of the year in the western Mediterranean Sea and in nearby Atlantic Ocean to cover heterogeneous environmental variability. Co-occurring adult sponges and offsprings were compared at two of the sites. To explore the composition and abundance of the main bacteria present in the sponge mesohyl, embryos, and larvae, we applied both 16S rRNA gene-denaturing gradient gel electrophoresis (DGGE) and sequencing of excised DGGE bands and quantitative polymerase chain reactions (qPCR). On average, the overall core bacterial assemblage showed over 60 % similarity. The associated bacterial assemblage fingerprints varied both within and between sponge populations, and the abundance of specific bacterial taxa assessed by qPCR significantly differed among sponge populations and between adult sponge and offsprings (higher proportions of Actinobacteria in the latter). Sequences showed between 92 and 100 % identity to sequences previously reported in GenBank, and all were affiliated with uncultured invertebrate bacterial symbionts (mainly sponges). Sequences were mainly related to Chloroflexi and Acidobacteria and a few to Actinobacteria and Bacteroidetes. Additional populations may have been present under detection limits. Overall, these results support that both ecological and biological sponge features may shape the composition of endobiont bacterial communities in S. lamella.  相似文献   

3.
The diversity and properties of actinobacteria, predominant residents in coral holobionts, have been rarely documented. In this study, we aimed to explore the species diversity, antimicrobial activities and biosynthetic potential of culturable actinomycetes within the tissues of the scleractinian corals Porites lutea, Galaxea fascicularis and Acropora millepora from the South China Sea. A total of 70 strains representing 13 families and 15 genera of actinobacteria were isolated. The antimicrobial activity and biosynthetic potential of fifteen representative filamentous actinomycetes were estimated. Crude fermentation extracts of 6 strains exhibited comparable or greater activities against Vibrio alginolyticus than ciprofloxacin. Seven of the 15 actinomycetes strains possess type I polyketide synthases (PKS-I) and/or nonribosomal peptide synthetases (NRPS) genes. Nine tested strains possess type II polyketide synthases (PKS-II). Phylogenetic analysis based on 16S rRNA gene sequences indicated that these PKS and NRPS gene screening positive strains belong to genera Nocardiopsis, Pseudonocardia, Streptomyces, Micromonospora, Amycolatopsis and Prauserella. One PKS-I and four NRPS fragments showed <70 % similarity to their closest relatives, which suggested the novelty of these genes. This study helps uncover the genetic capacity of stony coral-associated actinomycetes to produce bioactive molecules.  相似文献   

4.
5.
This study was conducted to determine effects of dietary supplementation with 1 % l-glutamine for 14 days on the abundance of intestinal bacteria and the activation of intestinal innate immunity in mice. The measured variables included (1) the abundance of Bacteroidetes, Firmicutes, Lactobacillus, Streptococcus and Bifidobacterium in the lumen of the small intestine; (2) the expression of toll-like receptors (TLRs), pro-inflammatory cytokines, and antibacterial substances secreted by Paneth cells and goblet cells in the jejunum, ileum and colon; and (3) the activation of TLR4-nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPK), and phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt) signaling pathways in the jejunum and ileum. In the jejunum, glutamine supplementation decreased the abundance of Firmicutes, while increased mRNA levels for antibacterial substances in association with the activation of NF-κB and PI3K-Akt pathways. In the ileum, glutamine supplementation induced a shift in the Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes, and enhanced mRNA levels for Tlr4, pro-inflammatory cytokines, and antibacterial substances participating in NF-κB and JNK signaling pathways. These results indicate that the effects of glutamine on the intestine vary with its segments and compartments. Collectively, dietary glutamine supplementation of mice beneficially alters intestinal bacterial community and activates the innate immunity in the small intestine through NF-κB, MAPK and PI3K-Akt signaling pathways.  相似文献   

6.
Hyperactive and inattentive children have been discussed in both the pedagogic and medical literature since the nineteenth century, and many controversies associated with attention deficit and hyperactivity disorder (ADHD) have been repeatedly analyzed in different contexts. The ‘prehistory’ of the ADHD concept—that is, up to the definition of ADHD in DSM-III and of the corresponding ‘hyperkinetic disorder’ in ICD-9—is outlined, with an emphasis on the literature not previously discussed in English language reviews of the subject.  相似文献   

7.
Obsessive compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) are two of the most common neuropsychiatric diseases in paediatric populations. The high comorbidity of ADHD and OCD with each other, especially of ADHD in paediatric OCD, is well described. OCD and ADHD often follow a chronic course with persistent rates of at least 40–50 %. Family studies showed high heritability in ADHD and OCD, and some genetic findings showed similar variants for both disorders of the same pathogenetic mechanisms, whereas other genetic findings may differentiate between ADHD and OCD. Neuropsychological and neuroimaging studies suggest that partly similar executive functions are affected in both disorders. The deficits in the corresponding brain networks may be responsible for the perseverative, compulsive symptoms in OCD but also for the disinhibited and impulsive symptoms characterizing ADHD. This article reviews the current literature of neuroimaging, neurochemical circuitry, neuropsychological and genetic findings considering similarities as well as differences between OCD and ADHD.  相似文献   

8.
Skin fibroblasts modulate tissue repair, wound healing and immunological responses. Adrenergic receptors (ARs) mediate important physiological functions, such as endocrine, metabolic and neuronal activity. In this study, the expression α1A-ARs in human skin fibroblasts is examined and verified. Regulatory effects of α1-agonist cirazoline on cell migration and the production of transforming growth factor β1 (TGF-β1), insulin-like growth factor 1 (IGF-1), hyaluronan (HA), fibronectin and procollagen type I carboxy-terminal peptide (PIP) by human skin fibroblasts are assessed and validated. α1A-AR mRNA and protein were found in human skin fibroblasts WS1. Exposure of cirazoline doubled skin fibroblast migration and the increase in cell migration was attenuated by α1-antagonist prazosin. TGF-β1 mRNA and production were enhanced after exposure to cirazoline and IGF-1 production was also increased after treatment with cirazoline. Exposure to cirazoline also enhanced HA and PIP production. The increases in TGF-β1, IGF-1, HA and PIP production were partially abolished in fibroblasts transfected with α1A-AR short interfering RNAs, indicating that α1A-ARs are involved in the cirazoline-induced increases in TGF-β1, IGF-1, HA and PIP production. Thus, α1A-ARs are stably expressed and stimulate cell migration and TGF-β1, IGF-1, HA and PIP production in human skin fibroblasts. Moreover, TGF-β1, IGF-1, HA and PIP production and the cell migration of human skin fibroblasts are possibly modulated by natural catecholamines produced by the endocrine system or sympathetic innervation, which could directly or indirectly participate in cytokine secretion, fibroblast migration and matrix production of wound healing in the skin.  相似文献   

9.
Matrix metalloproteinases (MMPs) play an important role in modeling of the extracellular matrix. There is increasing evidence that these proteases are important in neurite elongation and axonal guidance during development in the central nervous system and retina. Moreover, they are also expressed after acute injury and can be the key mediators of pathogenesis. However, the role of MMPs in the inner ear is largely unknown. Our group recently demonstrated that general inhibition of MMPs resulted in auditory hair cell loss in vitro. In the present study, we investigated the role of MMPs in inner ear spiral ganglion neuron (SGN) survival, neuritogenesis and neurite extension by blocking MMPs known to be involved in axonal guidance, neurite elongation, and apoptosis in other neuronal systems. Spiral ganglion (SG) explants from 5-day-old Wistar rats were treated with different concentrations of the general MMP inhibitor GM6001, a specific MMP-2 inhibitor, and a specific MMP-9 inhibitor, in vitro. The general inhibitor of MMPs and the specific inhibition of MMP-2 significantly reduced both the number of neurites that extended from SG explants, as well as the length of individual neurites. However, neither the general inhibitor of MMPs nor the specific inhibition of MMP-2 influenced SGN survival. Inhibition of MMP-9 had no influence on SGNs. The data suggest that MMPs, and more specifically MMP-2, influence the growth of developing afferent neurites in the mammalian inner ear in vivo.  相似文献   

10.
11.
A previous investigation showed that deep-sea water (DSW) can affect the expression of genes that regulate metastasis, including cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), urokinase plasminogen activator (uPA) and uPA receptor (uPAR), in HT-29 human colorectal adenocarcinomas. In the present study, we investigated the effects of DSW on inducible nitric oxide synthase (iNOS) expression and cell migration and also explored the mechanism of DSW-induced anti-metastatic potential in HT-29 human colorectal adenocarcinomas. Cytokine-induced expression of iNOS, which is highly expressed in colon cancer and enhances cancer growth and metastasis, was decreased in a hardness-dependent manner by DSW. Also, the wound healing assay revealed that DSW inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration in a hardness-dependent manner. DSW also decreased the phosphorylation of various MAPKs, including p38, ERK and JNK, and suppressed the nuclear translocation of NF-κB but not c-Jun. The results suggest that DSW may inhibit cancer cell growth related to iNOS overexpression and PKC-mediated cell migration in HT-29 human colorectal adenocarcinomas and the antimetastatic potential of DSW may be regulated by prevention of NF-κB nuclear translocation via inhibition of p38, ERK and JNK phosphorylation. In conclusion, the present investigation demonstrates that DSW inhibits cancer growth and metastasis via down-regulation of iNOS expression and the MAPK/NF-κB signaling pathway.  相似文献   

12.
Hepatocellular carcinoma (HCC) is a very aggressive neoplasia requiring early and accurate diagnosis to improve patient outcomes with timely treatment. The liver is also very frequently colonized by metastases, and the most frequent differential diagnosis is HCC against intrahepatic cholangiocarcinoma or metastatic adenocarcinoma. Metabolomics is a powerful tool for identification of altered biomarkers in cancer, and to evaluate the efficacy of drug treatments. Here we analyzed by HILIC-MS/MS methylated arginines, basic amino acids (Arg, Cit, Orn), and their ratios in the extracts of primary HCC tissues, liver metastases from colorectal carcinoma (MET), cirrhotic related hepatitis-C-virus (CIR), and non-cirrhotic normal liver (NT) adjacent tissues. We found high levels of Arg (p < 0.0001) and Arg/Orn (p < 0.01) in MET compared to other tissues. In MET, compared to NT and CIR, Arg concentration was fivefold higher, while in HCC it was twofold higher. ADMA increased twofold compared to NT and CIR, while in HCC it was 50 % higher. Arg/Cit and ADMA/SDMA ratios were significantly higher in MET compared to NT and CIR (p < 0.005). Arg/Orn, Arg/Cit, and ADMA/SDMA ratios increased progressively from NT, CIR, HCC, to MET tissues. Arg/Cit correlated significantly with Arg/Orn ratios (r = 0.77; p < 0.0001), and discriminates tumor from non-tumor samples. In addition, the discriminant lactate/glucose ratio we previously found by NMR, also correlated significantly with the Arg levels (r = 0.64; p < 0.0001), and discriminated MET from all other tissues. The results indicated that Arg in MET is higher than other tissue classes, suggesting that, together with the lactate/glucose ratio, it can be considered a further biomarker for HCC-metastases differentiation.  相似文献   

13.
The IUCN Red List of threatened species is biased towards vertebrate animals, a major limitation on its utility for overall biodiversity assessment. There is a need to increase the representation of invertebrates (currently 21 % of species assessed on the List; <1 % of all invertebrates). A prioritisation system of terrestrial and freshwater groups is presented here, categorising taxa by species richness, assessment practicality, value for human land use and bioindication, and potential to act as conservation flagships. 25 major taxonomic groupings were identified as priorities, including the Annelida, Arthropoda, Mollusca, and Onycophora. Of these, the high-level taxa that emerge as highest priorities are Odonata (dragonflies and damselflies), Araneae (spiders), Mantophasmatodea (heelwalkers), Plecoptera (stoneflies), non-marine Mollusca (Bivalvia and Gastropoda), Trichoptera (caddisflies), Coleoptera (beetles), Lepidoptera (moths and butterflies), Oligochaetes (earthworms), Orthoptera (grasshoppers and crickets), Decapoda (crayfish, crabs, shrimps) and Diptera (flies). Of these Red Listing is well advanced for Decapoda, freshwater Mollusca and Odonata. This leaves eight higher taxa with currently a minimum or patchy Red List assessment coverage. We recommend that Red List assessments in future focus on these groups, as well as completion of assessments for terrestrial Molluscs and Odonata. However, we also recommend realism, and as some of groups are very large, it will be necessary to focus on subsets such as certain functionally important or charismatic taxa or on a sampled subset which is representative of a larger taxon.  相似文献   

14.
As a part of ongoing studies to elucidate pharmacologically active components of Schisandra chinensis, we isolated and studied α-iso-cubebene. The neuroprotective mechanisms of α-iso-cubebene in human neuroblastoma SH-SY5Y cells were investigated. α-Iso-cubebene significantly inhibited cytotoxicity and apoptosis due to 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in dopaminergic SH-SY5Y cells. Pretreatment of cells with α-iso-cubebene reduced intracellular accumulation of ROS and calcium in response to 6-OHDA. The neuroprotective effects of α-iso-cubebene were found to result from protecting the mitochondrial membrane potential. Notably, α-iso-cubebene inhibited the release of apoptosis-inducing factor from the mitochondria into the cytosol and nucleus after 6-OHDA treatment. α-Iso-cubebene also induced the activation of PKA/PKB/CREB/Nrf2 and suppressed 6-OHDA-induced neurotoxicity. α-Iso-cubebene was found to induce phosphorylation of PKA and PKB and activate Nrf2 and CREB signaling pathways in a dose-dependent manner. Additionally, α-iso-cubebene stimulated the expression of the antioxidant response genes NQO1 and HO-1. Finally, α-iso-cubebene-mediated neuroprotective effects were found to be reversible after transfection with CREB and Nrf2 small interfering RNAs.  相似文献   

15.
Non-small cell lung cancer (NSCLC) is an intractable disease for which effective treatment approaches are urgently needed. The ability to induce antigen-specific immune responses in patients with lung cancer has led to the development of immunotherapy as a novel concept for the treatment of NSCLC. Adoptive cellular therapy (ACT) represents an important advancement in cancer immunotherapy with the utilization of tumor infiltrating lymphocytes, cytokine-induced killer cells, natural killer cells and γδ T cells. In this study, we review recent advances in ACT for NSCLC in clinical trials and provide a perspective on the improvement in ACT and potential therapeutic approaches using engineered T cell therapy for NSCLC.  相似文献   

16.
The urokinase-type plasminogen activator receptor (uPAR) serves not only as an anchor for urokinase-type plasminogen activator but also participates in intracellular signal transduction events. In this study, we investigated whether uPAR could modulate TRAIL-induced apoptosis in human colon cancer cells HCT116. Using an antisense strategy, we established a stable HCT116 cell line with down-regulated uPAR. The sensitivity to TRAIL-induced apoptosis was evaluated by FACS analysis. Our results show that the inhibition of uPAR could sensitize HCT116 to TRAIL-induced apoptosis. uPAR inhibition changed the expression of mitochondrial apoptotic pathway proteins, including Bcl-2, Bax, Bid and p53, in a pro-apoptotic manner. We also found that the inhibition of uPAR down-regulated the phosphorylation of FAK, ERK and JNK. The inhibition of p53 by RNA interference rescued cells from enhanced apoptosis, thus indicating that p53 is critical for enhancing TRAIL-induced apoptosis. Furthermore, JNK, but not ERK, inhibition involved in the up-regulation of p53. JNK negatively regulated p53 protein level. Overall, our results show that uPAR inhibition can sensitize colon cancer cells HCT116 to TRAIL-induced apoptosis via active p53 and mitochondrial apoptotic pathways that JNK inhibition is involved.  相似文献   

17.
The genetic factors of cancer predisposition remain elusive in the majority of familial and/or early-onset cases of breast cancer (BC). This type of BC is promoted by germ-line mutations that inactivate BRCA1 or BRCA2. On the other hand, recent studies have indicated that alterations in the levels of miRNA expression are linked to this disease. Although BRCA1 and BRCA2 gene mutations have been reported to commonly lead to alterations in genes that encode cancer-related proteins, little is known regarding the putative impact of these mutations on noncoding miRNAs. In the present study, we aimed to determine whether miRNA dysregulation is involved in the pathogenesis of BRCA-mutated BC. An expression analysis of 14 human miRNAs previously shown to be related to BC diagnosis, prognosis, and drug resistance was conducted using tissues from 60 familial and/or early-onset patients whose peripheral blood samples had been screened for BRCA1 and BRCA2 mutations through sequence analysis. Let-7a and miR-335 expression levels were significantly downregulated in the tumors of patients with a BRCA mutation compared with those of patients without a BRCA mutation (P = 0.04 and P = 0.02, respectively). Our results defined the associations between the expression status of let-7a and miR-335 and BRCA mutations. The expression analysis of these miRNAs might be used as biomarkers of the BRCA mutation status of early-onset and/or familial BC.  相似文献   

18.
19.
Transient receptor potential vanilloid type 4 (TRPV4) channels are expressed in the central nervous system, but their role in regulating the aging process under physiological and pathological conditions is still largely unknown. To identify age-related changes in the TRPV4 channel that contribute to the central nervous system, we investigated the distribution of TRPV4 in the brain and spinal cord regions of adult and aged rats. The expression of TRPV4 in the brain and spinal cord of adult and aged Sprague–Dawley rats was compared using immunohistochemistry performed with antibodies recognizing TRPV4 on free floating sections and western blotting analysis. TRPV4 immunoreactivity was significantly increased in the cerebral cortex, hippocampal formation, thalamus, basal nuclei, cerebellum and spinal cord of aged rats compared with adult control rats. In the cerebral cortex, TRPV4 immunoreactivity was significantly increased in pyramidal cells of aged rats. In addition, TRPV4 immunoreactivity was increased in the spinal cord, hippocampal formation, thalamus, basal nuclei and cerebellum of aged rats. This first demonstration of age-related increases in TRPV4 expression in the brain and spinal cord may provide useful data for investigating the pathogenesis of age-related neurodegenerative diseases. The exact regulatory mechanism and its functional significance require further elucidation.  相似文献   

20.
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world and its prevalence is rising. In the absence of disease progression, fatty liver poses minimal risk of detrimental health outcomes. However, advancement to non-alcoholic steatohepatitis (NASH) confers a markedly increased likelihood of developing severe liver pathologies, including fibrosis, cirrhosis, organ failure, and cancer. Although a substantial percentage of NAFLD patients develop NASH, the genetic and molecular mechanisms driving this progression are poorly understood, making it difficult to predict which patients will ultimately develop advanced liver disease. Deficiencies in mechanistic understanding preclude the identification of beneficial prognostic indicators and the development of effective therapies. Mouse models of progressive NAFLD serve as a complementary approach to the direct analysis of human patients. By providing an easily manipulated experimental system that can be rigorously controlled, they facilitate an improved understanding of disease development and progression. In this review, we discuss genetically- and chemically-induced models of NAFLD that progress to NASH, fibrosis, and liver cancer in the context of the major signaling pathways whose disruption has been implicated as a driving force for their development. Additionally, an overview of nutritional models of progressive NAFLD is provided.  相似文献   

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