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1.
We have analyzed the effect of the synthetic glucocorticoid dexamethasone, used alone or in combination with recombinant TRAIL, on in vitro osteoclastic differentiation of peripheral blood‐derived macrophages cultured in the presence of macrophage‐colony stimulating factor (M‐CSF) + RANKL for 12–14 days. Dexamethasone exhibited different effects based on the concentration used. Indeed, while at 10?7 M dexamethasone reduced the number of mature osteoclasts, at 10?8 M showed no significant effects and at 10?9 M significantly increased the number of mature osteoclasts, with respect to cells cultured with only M‐CSF + RANKL. On the other hand, the addition in culture of recombinant TRAIL inhibited the output of mature osteoclasts induced by M‐CSF + RANKL. However, the presence of dexamethasone (10?8 or 10?9 M) into the culture medium significantly counteracted the anti‐osteoclastic activity of TRAIL. In order to ascertain whether dexamethasone, might also interfere with the anti‐leukemic activity of TRAIL, the degree of apoptosis induced by TRAIL was evaluated in several myeloid (OCI, MOLM, HL‐60) and lymphoid (SKW6.4, MAVER, BJAB) leukemic cell lines. The levels of TRAIL‐triggered apoptosis were not significantly different between leukemic cells cultured in the absence or presence of dexamethasone. Concerning the molecular mechanism mediating the dexamethasone‐suppression of the TRAIL activity in pre‐osteoclasts, but not in leukemic cells, we found that dexamethasone induced a significant down‐regulation of the surface levels of TRAIL‐R2 in cells of the osteoclastic lineage but not in leukemic cells. The ability of dexamethasone to counteract the TRAIL pathway envisions a novel mechanism mediating the pro‐osteoclastic activity of dexamethasone in vivo. J. Cell. Physiol. 222: 357–364, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

2.
Our previous study revealed that the ethanolic extract of Justicia procumbens ameliorates ovalbumin‐induced airway inflammation and airway hyper‐responsiveness in a mouse model of asthma. However, the mechanism of action of the extract remains unknown. In this study, we prepared DW2008S, an optimized and standardized powder extracted from J. procumbens using anhydrous ethanol, and investigated its anti‐asthmatic effect and mechanism of action. Our results showed that DW2008S contains two major ingredients, justicidin A (JA) and justicidin B (JB), which selectively inhibit T helper 2 (Th2) cell responses in concanavalin A‐activated spleen cells and polarized Th2 cells. Blockade of T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine‐based inhibition motif domains (TIGIT) using a neutralizing antibody also selectively inhibited Th2 cell responses. Furthermore, DW2008S regulated TIGIT expression in the mice and cultured cells. Additionally, DW2008S and JA antagonized human adenosine receptor A3 (A3 AR), which mediates mast cell‐dependent inflammation and bronchoconstriction. DW2008S and JB inhibited human phosphodiesterase 4 (PDE4), which is known to cause bronchoconstriction; however, the required concentrations were higher than those needed to affect TIGIT . These findings suggest that DW2008S can potentially ameliorate Th2‐driven airway inflammation and bronchoconstriction through negative regulation of TIGIT and blockade of A3 AR and PDE4 activities.  相似文献   

3.
Phage‐displayed peptides recognized by two monoclonal antibodies against glucitollysine were selected. The most prominent feature of the peptide panel was the presence of paired Cys in most of them (21/24 peptides). The availability of a wide variety of peptides having differently spaced paired Cys, as well as truly linear Cys‐free peptides, gave the opportunity to explore the role of disulfide bridges in phage selection. Some Cys‐containing peptides came from a Cys‐flanked cyclic 9‐mer library, but most of them (18/21) were derived from a totally random 12‐mer library, and hence the presence of Cys was dictated by the selector antibodies. Motifs shared by several peptides (potentially involved in binding) often contained or were flanked by Cys residues. Binding of all Cys‐containing phage‐displayed peptides was abolished/decreased after a reducing treatment. Screening a random peptide library (without invariant Cys residues) is powerful enough to clearly reveal the need, preferences, and diversity of Cys‐mediated structural constraints for recognition. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

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Bovine lactoferricin (LfcinB) is a multi‐functional peptide derived from proteolytic cleavage of bovine lactoferrin. LfcinB was found to antagonize the biological effects mediated by angiogenic growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF‐2) in endothelial cells. However, the effect of LfcinB on human articular cartilage remained unknown. Here, our findings demonstrate that LfcinB restored the proteoglycan loss promoted by catabolic factors (interleukin‐1β) IL‐1β and FGF‐2 in vitro and ex vivo. Mechanistically, LfcinB attenuated the effects of IL‐1β and FGF‐2 on the expression of cartilage‐degrading enzymes (MMP‐1, MMP‐3, and MMP‐13), destructive cytokines (IL‐1β and IL‐6), and inflammatory mediators (iNOS and TLR2). LfcinB induced protective cytokine expression (IL‐4 and IL‐10), and downregulated aggrecanase basal expression. LfcinB specifically activated ERK MAPK and Akt signaling pathways, which may account for its anti‐inflammatory activity. We also revealed that LfcinB exerted similar protective effects on human synovial fibroblasts challenged by IL‐1β, with minimal cytotoxicity. Collectively, our results suggest that LfcinB possesses potent anti‐catabolic and anti‐inflammatory bioactivities in human articular tissues, and may be utilized for the prevention and/or treatment of OA in the future. J. Cell. Physiol. 228: 447–456, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

6.
doi:10.1111/j.1741‐2358.2009.00283.x
Implant‐retained thumb prosthesis with anti‐rotational attachment for a geriatric patient This report presents the use of a dental implant with an anti‐rotational attachment for the retention of a thumb prosthesis. A retention system was manufactured with an attachment (UCLA) screwed into the implant with a two‐bar system that was cast in metallic silver palladium. A substructure made from heat‐cured acrylic resin was joined to the retention system by clips to join the thumb to the finger (bar clip) in the cast with implant rejoinder. The silicone material, Silastic‐MDX 44210, was used to achieve function and aesthetics. Following osseointegration, no skin problems were observed. Whilst the implant‐retained digital prosthesis presented some motor limitations, it allowed the patient to return to entertainment and achieve social conviviality.  相似文献   

7.
Many real‐life stains have origins from biological matters including proteins, lipids, and carbohydrates that act as gluing agents binding along with other particulates or microbes to exposed surfaces of automobiles, furniture, and fabrics. Mimicking naturally occurring self‐defensive processes, we demonstrate in this work that a solid surface carrying partially exposed enzyme granules protected the surface in situ from contamination by biological stains and fingerprints. Attributed to the activities of enzymes which can be made compatible with a wide range of materials, such anti‐contamination and self‐cleaning functionalities are highly selective and efficient toward sticky chemicals. This observation promises a new mechanism in developing smart materials with desired anti‐microbial, self‐reporting, self‐cleaning, or self‐healing functions. Biotechnol. Bioeng. 2013; 110: 1805–1810. © 2013 Wiley Periodicals, Inc.  相似文献   

8.
The role of reactive oxygen species (ROS)‐mediated cell signal transduction pathways emanating from engineered cell substrates remains unclear. To elucidate the role, polymers derived from the amino acid L ‐tyrosine were used as synthetic matrix substrates. Variations in their chemical properties were created by co‐polymerizing hydrophobic L ‐tyrosine derivatives with uncharged hydrophilic poly(ethylene glycol) (PEG, Mw = 1,000 Da), and negatively charged desaminotyrosyl‐tyrosine (DT). These substrates were characterized for their intrinsic ability to generate ROS, as well as their ability to elicit Saos‐2 cell responses in terms of intracellular ROS production, actin remodeling, and apoptosis. PEG‐containing substrates induced both exogenous and intracellular ROS production, whereas the charged substrates reduced production of both types, indicating a coupling of exogenous ROS generation and intracellular ROS production. Furthermore, PEG‐mediated ROS induction caused nuclear translocation of glyceraldehyde‐3‐phosphate dehydrogenase and an increase in caspase‐3 activity, confirming a link with apoptosis. PEG‐rich pro‐oxidant substrates caused cytoskeletal actin remodeling through β‐actin cleavage by caspase‐3 into fractins. The fractins co‐localized to the mitochondria and reduced the mitochondrial membrane potential. The remnant cytosolic β‐actin was polymerized and condensed, events consistent with apoptotic cell shrinkage. The cytoskeletal remodeling was integral to the further augmentation of intracellular ROS production. Conversely, the anti‐oxidant DT‐containing charged substrates suppressed the entire cascade of apoptotic progression. We demonstrate that ROS activity serves an important role in “outside‐in” signaling for cells grown on substrates: the ROS activity couples exogenous stress, driven by substrate composition, to changes in intracellular signaling. This signaling causes cell apoptosis, which is mediated by actin remodeling. J. Cell. Physiol. 218: 549–557, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   

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The anti‐lipopolysaccharide factor ALF‐Pm3 is a 98‐residue protein identified in hemocytes from the black tiger shrimp Penaeus monodon. It was expressed in Pichia pastoris from the constitutive glyceraldehyde‐3‐phosphate dehydrogenase promoter as a folded and 15N uniformly labeled rALF‐Pm3 protein. Its 3D structure was established by NMR and consists of three α‐helices packed against a four‐stranded β‐sheet. The C34? C55 disulfide bond was shown to be essential for the structure stability. By using surface plasmon resonance, we demonstrated that rALF‐Pm3 binds to LPS, lipid A and to OM®‐174, a soluble analogue of lipid A. Biophysical studies of rALF‐Pm3/LPS and rALF‐Pm3/OM®‐174 complexes indicated rather high molecular sized aggregates, which prevented us to experimentally determine by NMR the binding mode of these lipids to rALF‐Pm3. However, on the basis of striking structural similarities to the FhuA/LPS complex, we designed an original model of the possible lipid A‐binding site of ALF‐Pm3. Such a binding site, located on the ALF‐Pm3 β‐sheet and involving seven charged residues, is well conserved in ALF‐L from Limulus polyphemus and in ALF‐T from Tachypleus tridentatus. In addition, our model is in agreement with experiments showing that β‐hairpin synthetic peptides corresponding to ALF‐L β‐sheet bind to LPS. Delineating lipid A‐binding site of ALFs will help go further in the de novo design of new antibacterial or LPS‐neutralizing drugs. © 2008 Wiley Periodicals, Inc. Biopolymers 91: 207–220, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com  相似文献   

11.
Current therapy for chronic kidney disease (CKD) is unsatisfactory because of an insufficient understanding of its pathogenesis. Matrix remodelling‐associated protein 5 (MXRA5, adlican) is a human protein of unknown function with high kidney tissue expression, not present in rodents. Given the increased expression of MXRA5 in injured tissues, including the kidneys, we have suggested that MXRA5 may modulate kidney injury. MXRA5 immunoreactivity was observed in tubular cells in human renal biopsies and in urine from CKD patients. We then explored factors regulating MXRA5 expression and MXRA5 function in cultured human proximal tubular epithelial cells and explored MXRA5 expression in kidney cancer cells and kidney tissue. The fibrogenic cytokine transforming growth factor‐β1 (TGFβ1) up‐regulated MXRA5 mRNA and protein expression. TGFβ1‐induced MXRA5 up‐regulation was prevented by either interference with TGFβ1 activation of the TGFβ receptor 1 (TGFBR1, ALK5) or by the vitamin D receptor agonist paricalcitol. By contrast, the pro‐inflammatory cytokine TWEAK did not modulate MXRA5 expression. MXRA5 siRNA‐induced down‐regulation of constitutive MXRA5 expression resulted in higher TWEAK‐induced expression of chemokines. In addition, MXRA5 down‐regulation resulted in a magnified expression of genes encoding extracellular matrix proteins in response to TGFβ1. Furthermore, in clear cell renal cancer, von Hippel–Lindau (VHL) regulated MXRA5 expression. In conclusion, MXRA5 is a TGFβ1‐ and VHL‐regulated protein and, for the first time, we identify MXRA5 functions as an anti‐inflammatory and anti‐fibrotic molecule. This information may yield clues to design novel therapeutic strategies in diseases characterized by inflammation and fibrosis.  相似文献   

12.
We evaluated sex, age, nutritional status, and infectious disease (ID) as predictors of two biomarkers of cell‐mediated immunity (CMI), delayed‐type hypersensitivity to Candida albicans (DTH‐Candida), and anti‐Epstein‐Barr virus antibody (EBV Ab), among 200 children in Kilimanjaro, Tanzania. DTH‐Candida, which decreases with compromised CMI, was positively associated with age (OR: 1.27; 95% CI: 1.02, 1.57) and triceps skinfold (TSF; OR: 1.16; 95% CI: 1.02, 1.26), and inversely associated with height‐for‐age Z score (HAZ; OR: 0.86; 95% CI: 0.68, 1.08) and diagnosed ID (OR: 0.48; 95% CI: 0.22, 1.08). There was significant interaction between TSF and ID: DTH‐Candida exhibited a strong inverse association with ID among children with low TSF (OR: 0.16; 95% CI: 0.05, 0.50) and a strong positive association with TSF among children with ID (OR: 2.64; 95% CI: 1.29, 5.42). EBV Ab, which increases with compromised CMI, was inversely associated with male sex (β: ?0.47; 95% CI: ?0.70, ?0.24) and TSF (β: ?0.04; 95% CI: ?0.08, 0.00), and positively associated with HAZ (β: 0.06; 95% CI: ?0.03, 0.15). Among males, EBV Ab was positively associated with anemia. Among normal HAZ children, EBV Ab was inversely associated with TSF. There was no association between DTH‐Candida and EBV Ab. While DTH‐Candida provides a direct measure of CMI, our results suggest that interpretation of EBV‐Ab among Kilimanjaro children was complicated by its indirect relationship with CMI. Among our sample, CMI increased with age and adequate nutrition and was compromised during acute ID. The suggestive CMI‐compromising effect of increasing height‐for‐age may bear further exploration. Am J Phys Anthropol 151:183–190, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

13.
Metastatic prostate cancer continues to be the second leading cause of cancer death in American men with an estimated 28,660 deaths in 2008. Recently, monocyte chemoattractant protein‐1 (MCP‐1, CCL2) has been identified as an important factor in the regulation of prostate metastasis. CCL2, shown to attract macrophages to the tumor site, has a direct promotional effect on tumor cell proliferation, migration, and survival. Previous studies have shown that anti‐CCL2 antibodies given in combination with docetaxel were able to induce tumor regression in a pre‐clinical prostate cancer model. A limitation for evaluating new treatments for metastatic prostate cancer to bone is the inability of imaging to objectively assess response to treatment. Diffusion‐weighted MRI (DW‐MRI) assesses response to anticancer therapies by quantifying the random (i.e., Brownian) motion of water molecules within the tumor mass, thus identifying cells undergoing apoptosis. We sought to measure the treatment response of prostate cancer in an osseous site to docetaxel, an anti‐CCL2 agent, and combination treatments using DW‐MRI. Measurements of tumor apparent diffusion coefficient (ADC) values were accomplished over time during a 14‐day treatment period and compared to response as measured by bioluminescence imaging and survival studies. The diffusion data provided early predictive evidence of the most effective therapy, with survival data results correlating with the DW‐MRI findings. DW‐MRI is under active investigation in the pre‐clinical and clinical settings to provide a sensitive and quantifiable means for early assessment of cancer treatment outcome. J. Cell. Biochem. 107: 58–64, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

14.
Ying Jin  Di Chen  Xiu Rong Zhang 《Chirality》2014,26(12):801-805
A series of cinchona alkaloid derivatives were used to catalyze the asymmetric anti‐Mannich‐type reaction of 3‐methyl‐2‐oxindole with N‐tosyl aryl aldimines. The resulting anti‐3,3‐disubstituted 2‐oxindole products were obtained in good yields (up to 92%) with high diastereo‐ and enantioselectivities (anti/syn up to 97:3 and 91% ee). Chirality 26:801–805, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

15.
Angiogenesis plays an important role in many pathological processes. Identification of novel anti‐angiogenic agents will provide new insights into the mechanisms for angiogenesis as well as potential lead compounds for developing new drugs. In the present study, a series of resveratrol methylated derivatives have been synthesized and screened. We found trans‐3,4‐dimethoxystilbene (3,4‐DMS) with the fullest potential to develop as an anti‐angiogenic agent. In vitro and in vivo analyses suggested that 3,4‐DMS could effectively inhibit endothelial cell proliferation, migration, tube formation, and endogenous neovascularization. Our results showed that 3,4‐DMS exerted its anti‐angiogenic effect likely through induction of endothelial cell apoptosis via a pathway involving p53, Bax, cytochrome c, and caspase proteases. Moreover, 3,4‐DMS also induced macroautophagy in endothelial cells through activation of AMPK and the downstream inhibition of mTOR signaling pathway. Further studies indicated that intracellular calcium ([Ca2+]i) might bridge the 3,4‐DMS‐induced apoptosis and macroautophagy through modulating reactive oxygen species (ROS) levels in endothelial cells. Combination of 3,4‐DMS with inhibitor of autophagy, such as 3‐methyladenine (3‐MA) and autophagy‐related gene (ATG) 5 small interfering RNA (siRNA), potentiated the pro‐apoptotic and anti‐angiogenic effects of 3,4‐DMS. Our study provides a novel angiogenic inhibitor and a useful tool in exploring the molecular mechanisms for the crosstalk between apoptosis and macroautophagy in endothelial cells. 3,4‐DMS could be served as a potential lead compound for developing a class of new drugs targeting angiogenesis‐related diseases. J. Cell. Biochem. 114: 697–707, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

16.
The article to which this erratum refers was published in J. Cell. Biochem. 104: 1937–1945, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

17.
The catabolic cytokine interleukin‐1 (IL‐1) and endotoxin lipopolysaccharide (LPS) are well‐known inflammatory mediators involved in degenerative disc disease, and inhibitors of IL‐1 and LPS may potentially be used to slow or prevent disc degeneration in vivo. Here, we elucidate the striking anti‐catabolic and anti‐inflammatory effects of bovine lactoferricin (LfcinB) in the intervertebral disc (IVD) via antagonism of both IL‐1 and LPS‐mediated catabolic activity using in vitro and ex vivo analyses. Specifically, we demonstrate the biological counteraction of LfcinB against IL‐1 and LPS‐mediated proteoglycan (PG) depletion, matrix‐degrading enzyme production, and enzyme activity in long‐term (alginate beads) and short‐term (monolayer) culture models using bovine and human nucleus pulposus (NP) cells. LfcinB significantly attenuates the IL‐1 and LPS‐mediated suppression of PG production and synthesis, and thus restores PG accumulation and pericellular matrix formation. Simultaneously, LfcinB antagonizes catabolic factor mediated induction of multiple cartilage‐degrading enzymes, including MMP‐1, MMP‐3, MMP‐13, ADAMTS‐4, and ADAMTS‐5, in bovine NP cells at both mRNA and protein levels. LfcinB also suppresses the catabolic factor‐induced stimulation of oxidative and inflammatory factors such as iNOS, IL‐6, and toll‐like receptor‐2 (TLR‐2) and TLR‐4. Finally, the ability of LfcinB to antagonize IL‐1 and LPS‐mediated suppression of PG is upheld in an en bloc intradiscal microinjection model followed by ex vivo organ culture using both mouse and rabbit IVD tissue, suggesting a potential therapeutic benefit of LfcinB on degenerative disc disease in the future. J. Cell. Physiol. 228: 1884–1896, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

18.
The autonomic nervous system consists of sympathetic and parasympathetic nerves, which functionally antagonize each other to control physiology and homeostasis of organs. However, it is largely unexplored how the autonomic nervous system is established during development. In particular, early formation of parasympathetic network remains elusive because of its complex anatomical structure. To distinguish between parasympathetic (cholinergic) and sympathetic (adrenergic) ganglia, vesicular acetylcholine transporter (VAChT) and choline O‐acetyltransferase (ChAT), proteins associated with acetylcholine synthesis, are known to be useful markers. Whereas commercially available antibodies against these proteins are widely used for mammalian specimens including mice and rats, these antibodies do not work satisfactorily in chickens, although chicken is an excellent model for the study of autonomic nervous system. Here, we newly raised antibodies against chicken VAChT and ChAT proteins. One monoclonal and three polyclonal antibodies for VAChT, and one polyclonal antibody for ChAT were obtained, which were available for Western blotting analyses and immunohistochemistry. Using these verified antibodies, we detected cholinergic cells in Remak ganglia of autonomic nervous system, which form in the dorsal aspect of the digestive tract of chicken E13 embryos. The antibodies obtained in this study are useful for visualization of cholinergic neurons including parasympathetic ganglia.  相似文献   

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