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1.
The LTBPs (or latent transforming growth factor β binding proteins) are important components of the extracellular matrix (ECM) that interact with fibrillin microfibrils and have a number of different roles in microfibril biology. There are four LTBPs isoforms in the human genome (LTBP-1, − 2, − 3, and − 4), all of which appear to associate with fibrillin and the biology of each isoform is reviewed here.The LTBPs were first identified as forming latent complexes with TGFβ by covalently binding the TGFβ propeptide (LAP) via disulfide bonds in the endoplasmic reticulum. LAP in turn is cleaved from the mature TGFβ precursor in the trans-golgi network but LAP and TGFβ remain strongly bound through non-covalent interactions. LAP, TGFβ, and LTBP together form the large latent complex (LLC). LTBPs were originally thought to primarily play a role in maintaining TGFβ latency and targeting the latent growth factor to the extracellular matrix (ECM), but it has also been shown that LTBP-1 participates in TGFβ activation by integrins and may also regulate activation by proteases and other factors. LTBP-3 appears to have a role in skeletal formation including tooth development. As well as having important functions in TGFβ regulation, TGFβ-independent activities have recently been identified for LTBP-2 and LTBP-4 in stabilizing microfibril bundles and regulating elastic fiber assembly.  相似文献   

2.
Successful antral formation in vitro from bovine preantral follicles (145–170 μm) has been described previously, but antrum formation from the primary follicle (50–70 μm) has not yet been achieved in vitro. The aim of the study was to establish an optimal culture system supporting the growth and maturation of bovine primary follicles (50–70 μm) in vitro. Bovine primary follicles were cultured in a three-dimensional culture system for 13 or 21 days in alpha-minimum essential medium. Various treatments including follicle stimulating hormone (FSH), luteinizing hormone (LH), 17β-estradiol (E2), basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) were tested. The follicular diameter and antrum formation rate were recorded, and follicular maturation markers (P450 aromatase, CYP19A1; anti-Mullerian hormone, AMH; growth differentiation factor-9, GDF9; bone morphogenetic protein-15, BMP15; and type III transforming growth factor β receptor, TGFβR3) were analyzed by real-time RT-PCR. After 21 days of culture under each treatment condition, the follicular diameter was significantly enlarged in the presence of FSH + LH + E2 + bFGF or FSH + LH + E2 + bFGF + EGF (p < 0.05). An addition of 50 ng/ml bFGF or bFGF + 25 ng/ml EGF initiated antrum formation by day 19 and day 17 of culture, and the antral cavity formation rate was 16.7% and 33.3% by 21 days of culture, respectively. The expression of follicular maturation markers (CYP19A1, AMH, GDF9, BMP15 and TGFβR3) was significantly altered. We conclude that addition of 50 ng/ml bFGF + 25 ng/ml EGF to media containing FSH + LH + E2 turned out to be the most effective optimized culture conditions to support the growth and maturation of bovine primary follicles in vitro.  相似文献   

3.
The aim of this study was to determine the efficacy of dietary administration of Lactobacillus pentosus PL11 on growth performance and the immune and antioxidant systems in Japanese eel Anguilla japonica challenged with Edwardsiella tarda. A total of 75 Japanese eels (24.63 ± 0.83 g) were grouped into 5 treatment diets which were a control diet (C) without E. tarda and 4 treatment diets with E. tarda challenge, including C for E. tarda challenge (NC), C plus L. pentosus PL11 supplemented diet (108 cfu g?1) (T-PL11), C plus L. pentosus KCCM 40997 supplemented diet (108 cfu g?1) (T-Lp) and C plus Weissella hellenica DS-12 supplemented diet (108 cfu g?1) (T-Wh) for 5 weeks (4 week before and 1 week after challenge). The results showed enhanced growth performance in fish fed the diet containing L. pentosus PL11 compared to others. The growth performance parameters including specific growth rate (SGR) and weight gain (WG), feed intake (FI), feed conversion ratio (FCR) and survival were significantly (P < 0.05) higher in fish maintained on L. pentosus PL11 supplemented diet compared to C and NC. T-PL11 group also shows a significant increase in the levels of plasma immunoglobulin M, CAT and SOD activities compared to NC. Hematological parameters and mieloperoxidase were significantly better in fish fed the L. pentosus PL11 supplemented diet than in the control. L. pentosus PL11 supplementation recover the reduced expression of SOD, CAT and heat shock protein 70 genes in liver and intestine in pathogen challenged fishes. In conclusion the result of the current study demonstrated L. pentosus PL11 potential as an alternative to antibiotic supplementation to improve the growth and health performance of Japanese eel (A. japonica).  相似文献   

4.
BackgroundPreeclampsia is a pregnancy specific disorder affecting 3–5% of pregnancies worldwide. It is clinically divided into early-onset and late-onset subtypes. Placental factors are involved in the pathogenesis of preeclampsia. Growth differentiation factor 15 (GDF15), a protein of the transforming growth factor beta superfamily, is highly expressed in the placenta. However, it is unclear whether the circulating levels of GDF15 are altered in preeclampsia at the time of or prior to disease presentation.MethodsSerum samples across three trimesters from 29 healthy pregnancies, third trimester sera from 34 women presenting with preeclampsia (early-onset n = 16, late-onset n = 18) and 66 gestation-age-matched controls, and sera at 11–13 weeks of pregnancy from women who later did (n = 36) or did not (n = 33) develop late-onset preeclampsia, were examined for GDF15 by ELISA.ResultsSerum GDF15 levels increased significantly with gestation in normal pregnancy. Serum GDF15 was significantly reduced in the third trimester in women presenting with preeclampsia compared to their gestation-age-matched controls. This reduction was apparent in both early-onset and late-onset subtypes, but it was more profound in late-onset cases. At 11–13 weeks of gestation, however, serum levels of GDF15 were similar between women who subsequently did and did not develop late-onset preeclampsia.ConclusionSerum GDF15 increased with gestation age, reaching the highest level in the third trimester. Serum GDF15 was significantly reduced in the third trimester in women presenting with preeclampsia, especially in late-onset cases. However, serum GDF15 was not altered in the first trimester in women destined to develop late-onset preeclampsia.  相似文献   

5.
Outer membrane protein A (OmpA) is a component of the outer membrane of Edwardsiella tarda and is wildly distributed in Enterobacteriaceae family. The gene encoding the OmpA protein was cloned from E. tarda and expressed in Escherichia coli M15 cells. The recombinant OmpA protein containing His6 residues was estimated to have a molecular weight of ∼38 kDa. In Western blot the native protein showed expression at ∼36 kDa molecular weight which was within the range of major outer membrane proteins (36–44 kDa) observed in this study. All E. tarda isolates tested harbored the ompA gene and the antibody raised to this protein was seen to cross react with other Gram negative bacteria. The OmpA protein characterized in this study was observed to be highly immunogenic in both rabbit and fish. In Enzyme linked immunosorbent assay, rabbit antisera showed an antibody titer of 1: 128,000. Common carp vaccinated with recombinant OmpA protein elicited high antibody production and immunized fish showed a relative percentage survival of 54.3 on challenge.  相似文献   

6.
Studies on how flatfish cardiovascular function responds to environmental challenges are limited, and have largely relied upon indirect methodologies (i.e. Fick principle). Thus, we measured dorsal aortic blood pressure (PDA) and cardiac function in 8 and 15 °C-acclimated flounder exposed to graded hypoxia, and in 8 °C-acclimated fish exposed to an acute temperature increase to their critical thermal maximum (CTM). The extent of bradycardia in 8 °C-acclimated fish (decrease in heart rate of 41%) was consistent with that observed for other teleosts, as was this species' CTM (25.8 ± 0.5 °C) and its cardiac response to increasing temperature. However, this study provides further examples of how cardiovascular function is controlled differently in the flounder as compared with other fishes. First, the onset of bradycardia in 8 °C-acclimated fish occurred earlier than expected for this inactive and hypoxia-tolerant species (60% water air saturation). Second, resting cardiac output was similar in flounder acclimated to 8 and 15 °C (~ 15 mL min? 1 kg? 1), and hypoxic bradycardia was surprisingly absent at 15 °C. Finally, systemic vascular resistance decreased when flounder were exposed to elevated temperature, and this resulted in a 26% fall in PDA. These are novel findings, however, the extent to which the flounder's behaviour influenced some of the results is unclear.  相似文献   

7.
8.
《Médecine Nucléaire》2017,41(1):15-20
ObjectiveFCH-PET/CT protocol for prostate cancer assessment consists of an early and late acquisition. Concerning the early acquisition, this study compares contrast-to-noise ratio of tumoral lesions between 5 and 10 minutes post-injection in order to shorten the time of this early acquisition.Materials and methodsPatients with proven prostate cancer referred for initial staging or recurrence were prospectively included. Patients underwent 10 minutes of pelvic dynamic acquisition for the early phase and late phase was performed at 60 minutes post-injection. Contrast-to-noise of lesions at 5 and 10 min post-injection were compared.ResultsForty-nine patients with 77 lesions were analyzed. No significant difference of prostatic lesions contrast-to-noise ratio was found between 5 min and 10 min post-injection (median contrast-to-noise ratio was respectively 38 and 42, P = 0.128).ConclusionThese results could have an impact on clinical practice with FCH-PET/CT early acquisition shortened to 5 min post-injection for patients with prostate cancer.  相似文献   

9.
Tendon-like tissue generated from stem cells in vitro has the potential to replace tendons and ligaments lost through injury and disease. However, thus far, no information has been available on the mechanism of tendon formation in vitro and how to accelerate the process. We show here that human mesenchymal stem cells (MSCs) and bone marrow-derived mononuclear cells (BM-MNCs) can generate tendon-like tissue in 7 days mediated by transforming growth factor (TGF) β3. MSCs cultured in fixed-length fibrin gels spontaneously synthesized narrow-diameter collagen fibrils and exhibited fibripositors (actin-rich, collagen fibril-containing plasma membrane protrusions) identical to those that occur in embryonic tendon. In contrast, BM-MNCs did not synthesize tendon-like tissue under these conditions. We performed real-time PCR analysis of MSCs and BM-MNCs. MSCs upregulated genes encoding type I collagen, TGFβ3, and Smad2 at the time of maximum contraction of the tendon-like tissue (7 days). Western blot analysis showed phosphorylation of Smad2 at maximum contraction. The TGFβ inhibitor SB-431542, blocked the phosphorylation of Smad2 and stopped the formation of tendon-like tissue. Quantitative PCR showed that BM-MNCs expressed very low levels of TGFβ3 compared to MSCs. Therefore we added exogenous TGFβ3 protein to BM-MNCs in fibrin gels, which resulted in phosphorylation of Smad2, synthesis of collagen fibrils, the appearance of fibripositors at the plasma membrane, and the formation of tendon-like tissue. In conclusion, MSCs that self-generate TGFβ signaling or the addition of TGFβ3 protein to BM-MNCs in fixed-length fibrin gels spontaneously make embryonic tendon-like tissue in vitro within 7 days.  相似文献   

10.
We have recently demonstrated that fibrillin-1 assemblies regulate the fate of skeletal stem cells (aka, mesenchymal stem cells [MSCs]) by modulating TGFβ activity within the microenvironment of adult bone marrow niches. Since MSCs can also influence hematopoietic stem cell (HSC) activities, here we investigated adult hematopoiesis in mice with Cre-mediated inactivation of the fibrillin-1 (Fbn1) gene in the mesenchyme of the forming limbs (Fbn1Prx1 / mice). Analyses of 3-month-old Fbn1Prx1 / mice revealed a statistically significant increase of circulating red blood cells, which a differentiation assay correlated with augmented erythropoiesis. This finding, together with evidence of fibrillin-1 deposition in erythroblastic niches, supported the notion that this extracellular matrix protein normally restricts differentiation of erythroid progenitors. Whereas flow cytometry measurements identified a decreased HSC frequency in mutant relative to wild type mice, no appreciable differences were noted with regard to the relative abundance and differentiation potential of myeloid progenitor cells. Together these findings implied that fibrillin-1 normally promotes HSC expansion but does not influence cell lineage commitment. Since local TGFβ hyperactivity has been associated with abnormal osteogenesis in Fbn1Prx1 / mice, 1-month-old mutant and wild type animals were systemically treated for 8 weeks with either a pan-TGF-β-neutralizing antibody or an antibody of the same IgG1 isotype. The distinct outcomes of these pharmacological interventions strongly suggest that fibrillin-1 differentially modulates TGFβ activity in HSC vs. erythroid niches.  相似文献   

11.
Arsenic, the environmental toxicant causes oxidative damage to liver and produces hepatic fibrosis. The theme of our study was to evaluate the therapeutic efficacy of liposomal and nanocapsulated herbal polyphenolic antioxidant Quercetin (QC) in combating arsenic induced hepatic oxidative stress, fibrosis associated upregulation of its gene expression and plasma TGF ß (transforming growth factor ß) in rat model.A single dose of Arsenic (sodium arsenite-NaAsO2, 13 mg/kg b.wt) in oral route causes the generation of reactive oxygen species (ROS), arsenic accumulation in liver, hepatotoxicity and decrease in hepatic plasma membrane microviscosity and antioxidant enzyme levels in liver. Arsenic causes fibrosis associated elevation of its gene expression in liver, plasma TGF ß (from normal value 75.2 ± 8.67 ng/ml to 196.2 ± 12.07 ng/ml) and release of cytochrome c in cytoplasm. Among the two vesicular delivery systems formulated with QC, polylactide nanocapsules showed a promising result compared to liposomal delivery system in controlling arsenic induced alteration of those parameters. A single dose of 0.5 ml of nanocapsulated QC suspension (QC 2.71 mg/kg b.wt) when injected to rats 1 h after arsenic administration orally protects liver from arsenic induced deterioration of antioxidant levels as well as oxidative stress associated gene expression of liver. Histopathological examination also confirmed the pathological improvement in liver. Nanocapsulated plant origin flavonoidal compound may be a potent formulation in combating arsenic induced upregulation of gene expression of liver fibrosis through a complete protection against oxidative attack in hepatic cells of rat liver.  相似文献   

12.
13.
In vivo imaging of β-amyloid (Aβ) aggregates consisting of Aβ(1–40) and Aβ(1–42) peptides by positron emission tomography (PET) contributes to the diagnosis and therapy for Alzheimer’s disease (AD). Because 64Cu (t1/2 = 12.7 h) is a radionuclide for PET with a longer physical half-life than 11C (t1/2 = 20 min) and 18F (t1/2 = 110 min), it is an attractive radionuclide for the development of Aβ imaging probes that are suitable for routine use. In the present study, we designed and synthesized two novel 64Cu labeled benzofuran derivatives and evaluated their utility as PET imaging probes for Aβ aggregates. In an in vitro binding assay, 6 and 8 showed binding affinity for Aβ(1–42) aggregates with a Ki value of 33 and 243 nM, respectively. In addition, these probes bound to Aβ plaques deposited in the brain of an AD model mouse in vitro. In a biodistribution experiment using normal mice, these probes showed low brain uptake (0.33% and 0.36% ID/g) at 2 min post-injection. Although refinement to enhance brain uptake is needed, [64Cu]6 and [64Cu]8 demonstrated the feasibility of developing novel PET probes for imaging Aβ aggregates.  相似文献   

14.
The host-defense peptide, esculentin-2CHa (GFSSIFRGVA10KFASKGLGK D20LAKLGVDLVA30 CKISKQC) shows potent (MIC  6 μM) growth inhibitory activity against clinical isolates of multidrug-resistant strains of Staphylococcus aureus, Acinetobacter baumannii, and Stenotrophomonas maltophilia and differential cytotoxic activity against human erythrocytes (LC50 = 150 μM) and human non-small cell lung adenocarcinoma A549 cells (LC50 = 10 μM). Esculentin-2CHa significantly (P < 0.01) stimulates the release of the anti-inflammatory cytokine IL-10 by mouse lymphoid cells and elevates its production after stimulation with concanavalin A and significantly (P < 0.05) stimulates TNF-α production by peritoneal macrophages. Effects on IL-6 and IL-1β production were not significant. Removal of the hydrophobic N-terminal hexapeptide (GFSSIF) from esculentin-2CHa results in abolition of growth inhibitory activity against S. aureus and cytotoxic activity against erythrocytes and A549 cells as well as a marked (≥16-fold) reduction in potency against A. baumannii and S. maltophilia. The primary structure of esculentin-2 has been poorly conserved between frog species but evolutionary pressure has acted to maintain the hydrophobic character of this N-terminal hexapeptide sequence. Removal of the cyclic C-terminal domain (CKISKQC) and replacement of the Cys31 and Cys37 residues by serine resulted in appreciable decreases in cytotoxicity against all microorganisms and against mammalian cells. The more cationic [D20K, D27K] analog showed a modest increase in potency against all microorganisms (up to 4-fold) but a marked increase in cytotoxicity against erythrocytes (LC50 = 11 μM) and A549 cells (LC50 = 3 μM).  相似文献   

15.
Since the imaging of β-amyloid (Aβ) plaques in the brain is believed to be a useful tool for the early diagnosis of Alzheimer’s disease (AD), a number of imaging probes to detect Aβ plaques have been developed. Because the radionuclide 68Ga (t1/2 = 68 min) for PET imaging could become an attractive alternative to 11C and 18F, we designed and synthesized a benzofuran derivative conjugated with a 68Ga complex (68Ga-DOTA-C3-BF) as a novel Aβ imaging probe. In an in vitro binding assay, Ga-DOTA-C3-BF showed high affinity for Aβ(1-42) aggregates (Ki = 10.8 nM). The Ga-DOTA-C3-BF clearly stained Aβ plaques in a section of Tg2576 mouse, reflecting the affinity for Aβ(1-42) aggregates in vitro. In a biodistribution study in normal mice, 68Ga-DOTA-C3-BF displayed low initial uptake (0.45% ID/g) in the brain at 2 min post-injection. While improvement of the brain uptake of 68Ga complexes appears to be essential, these results suggest that novel PET imaging probes that include 68Ga as the radionuclide for PET may be feasible.  相似文献   

16.
17.
Amplified fragment length polymorphism (AFLP) analysis was performed in order to evaluate genetic characteristics of one common population and two selective hatchery populations of flounder Paralichthys olivaceus. A group of 60 genotypes belonging to three populations was screened using 10 different AFLP primer combinations. A total of 491 loci were produced in the three studied populations. The loci of 65.78%, 61.47% and 60.92% were polymorphic over all the genotypes tested in common, susceptible and resistant populations, respectively. The number of polymorphic loci detected by single primer combination ranged from 21 to 43. The average heterozygosity of common, susceptible and resistant populations was 0.1656, 0.1609 and 0.1586, respectively, which showed no significant difference. Compared with the common population, the two selective hatchery populations, susceptible and resistant, showed significant genetic differences including a smaller (P < 0.05) number of total loci, a smaller (P < 0.05) number of total polymorphic loci and a smaller (P < 0.05) percentage of low frequency (0–0.2) polymorphic loci. AFLP banding pattern was transformed into binary data and matrices were processed with POPGENE and TFPGA software. Similarity relationships were described graphically by a dendrogram, which clustered the three populations. The AFLP fingerprinting technique was confirmed to be a reproducible and sensitive tool for the study of population genetics of flounder. The present study confirmed that it was important to detect the genetic variability of the selective hatchery populations for the conservation of natural flounder resources.  相似文献   

18.
We have recently characterized bicarinalin as the most abundant peptide from the venom of the ant Tetramorium bicarinatum. This antimicrobial peptide is active against Staphylococcus and Enterobacteriaceae. To further investigate the antimicrobial properties of this cationic and cysteine-free peptide, we have studied its antibacterial, antifungal and antiparasitic activities on a large array of microorganisms. Bicarinalin was active against fifteen microorganisms with minimal inhibitory concentrations ranging from 2 and 25 μmol L−1. Cronobacter sakazakii, Salmonella enterica, Candida albicans, Aspergilus niger and Saccharomyces cerevisiae were particularly susceptible to this novel antimicrobial peptide. Resistant strains of Staphylococcus aureus, Pseudomonas aeruginosa and C. albicans were as susceptible as the canonical strains. Interestingly, bicarinalin was also active against the parasite Leishmania infantum with a minimal inhibitory concentrations of 2 μmol L−1. The bicarinalin pre-propeptide cDNA sequence has been determined using a combination of degenerated primers with RACE PCR strategy. Interestingly, the N-terminal domain of bicarinalin pre-propeptide exhibited sequence similarity with the pilosulin antimicrobial peptide family previously described in the Myrmecia venoms. Moreover, using SYTOX green uptake assay, we showed that, for all the tested microorganisms, bicarinalin acted through a membrane permeabilization mechanism. Two dimensional-NMR experiments showed that bicarinalin displayed a 10 residue-long α-helical structure flanked by two N- and C-terminal disordered regions. This partially amphipathic helix may explain the membrane permeabilization mechanism of bicarinalin observed in this study. Finally, therapeutic value of bicarinalin was highlighted by its low cytotoxicity against human lymphocytes at bactericidal concentrations and its long half-life in human serum which was around 15 h.  相似文献   

19.
Norepinephrine-stimulated skin secretions of the Tyrrhenian painted frog Discoglossus sardus Tschudi, 1837 (Alytidae) did not contain any peptide with antimicrobial or hemolytic activity. However, peptidomic analysis of the secretions revealed the presence of an abundant peptide with structural similarity to frenatin 2, previously isolated from the Australian frog Litoria infrafrenata (Hylidae). The primary structure of the peptide, termed frenatin 2D, was established as DLLGTLGNLPLPFI.NH2 by automated Edman degradation and mass spectrometry with electron-transfer dissociation (ETD)-based fragmentation and confirmed by chemical synthesis. The structure of a second frenatin 2-related peptide, termed frenatin 2.1D, that was present in much lower abundance was established as GTLGNLPAPFPG. Frenatin 2D (20 μg/ml) significantly stimulated production of the proinflammatory cytokines TNF-α (P < 0.05) and IL-1β (P < 0.01) by mouse peritoneal macrophages but the peptide did not potentiate the stimulation produced by lipopolysaccharide (LPS). The peptide increased IL-12 production in both unstimulated (P < 0.01) and LPS-stimulated (P < 0.05) cells but stimulatory effects on IL-6 production were not significant. The biological role of frenatin 2D is unknown but it is speculated that the peptide acts on skin macrophages to produce a cytokine-mediated stimulation of the adaptive immune system in response to invasion by microorganisms.  相似文献   

20.
AimsThe aim of this study was to gain insight in the inflammatory response in acute heart failure (AHF) by assessing (1) plasma cytokine profiles and (2) prognostic value of circulating cytokines in AHF patients.Methods and resultsPlasma levels of 26 cytokines were quantified by multiplex protein arrays in 36 patients with congestive AHF, characterized by echocardiographic, radiologic, and clinical examinations on admission, during hospitalization and at discharge. Recurrent AHF leading to death or readmission constituted the combined end point, and all patients were followed for 120 days after discharge. Levels of 15 of the measured cytokines were higher in AHF than in healthy subjects (n = 22) on admission. Low levels of MCP-1, IL-1β and a low IL-1β/IL-1ra ratio predicted fatal and non-fatal AHF within 120 days. Patients with low circulating levels of IL-1β had lower left ventricular ejection fraction and higher levels of N-terminal pro-B-type natriuretic peptide, while patients with low levels of MCP-1 had higher E/E′ and inferior caval vein diameter, than patients with high levels.ConclusionImmune activation, reflected in increased cytokine levels, is present in AHF patients. Interestingly, failure to increase secretion of IL-1β and MCP-1 during AHF is associated with poor outcome.  相似文献   

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