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Sample records for hyaluronan ha binding

  1. Brain hyaluronan binding protein inhibits tumor growth

    Institute of Scientific and Technical Information of China (English)

    高锋; 曹曼林; 王蕾

    2004-01-01

    Background Great efforts have been made to search for the angiogenic inhibitors in avascular tissues. Several proteins isolated from cartilage have been proved to have anti-angiogenic or anti-tumour effects. Because cartilage contains a great amount of hyaluronic acid (HA) oligosaccharides and abundant HA binding proteins (HABP), therefore, we speculated that HABP might be one of the factors regulating vascularization in cartilage or anti-angiogenesis in tumours. The purpose of this research was to evaluale the effects of hyaluronan binding protein on inhibiting tumour growth both in vivo and vitro. Methods A unique protein termed human brain hyaluronan (HA) binding protein (b-HABP) was cloned from human brain cDNA library. MDA-435 human breast cancer cell line was chosen as a transfectant. The in vitro underlying mechanisms were investigated by determining the possibilities of MDA-435/b-HABP colony formation on soft agar, the effects of the transfectant on the proliferation of endothelial cells and the expression levels of caspase 3 and FasL from MDA-435/b-HABP. The in vivo study included tumour growth on the chorioallantoic membrane (CAM) of chicken embryos and nude mice. Results Colony formation assay revealed that the colonies formed by MDA-435/b-HABP were greatly reduced compared to mock transfectants. The conditioned media from MDA-435/b-HABP inhibited the growth of endothelial cells in culture. Caspase 3 and FasL expressions were induced by MDA-435/b-HABP. The size of tumours of MDA-435/b-HABP in both CAM and nude mice was much smaller than that of MDA-435 alone. Conclusions Human brain hyaluronan binding protein (b-HABP) may represent a new kind of naturally existing anti-tumour substance. This brain-derived glycoprotein may block tumour growth by inducing apoptosis of cancer cells or by decreasing angiogenesis in tumour tissue via inhibiting proliferation of endothelial cells.

  2. Role of hyaluronan and hyaluronan-binding proteins in lung pathobiology.

    Science.gov (United States)

    Lennon, Frances E; Singleton, Patrick A

    2011-08-01

    Hyaluronan (HA) has diverse functions in normal lung homeostasis and pulmonary disease. HA constitutes the major glycosaminoglycan in lung tissue, with HA degradation products, produced by hyaluronidase enzymes and reactive oxygen species, being implicated in several lung diseases, including acute lung injury, asthma, chronic obstructive pulmonary disease, and pulmonary hypertension. The differential activities of HA and its degradation products are due, in part, to regulation of multiple HA-binding proteins, including cluster of differentiation 44 (CD44), Toll-like receptor 4 (TLR4), HA-binding protein 2 (HABP2), and receptor for HA-mediated motility (RHAMM). Recent research indicates that exogenous administration of high-molecular-weight HA can serve as a novel therapeutic intervention for lung diseases, including lipopolysaccharide (LPS)-induced acute lung injury, sepsis/ventilator-induced lung injury, and airway hyperreactivity. This review focuses on the regulatory role of HA and HA-binding proteins in lung pathology and discusses the capacity of HA to augment and inhibit various lung diseases.

  3. The where, when, how and why of hyaluronan binding by immune cells

    Directory of Open Access Journals (Sweden)

    Sally S. M. Lee-Sayer

    2015-04-01

    Full Text Available Hyaluronan is made and extruded from cells to form a pericellular or extracellular matrix (ECM and is present in virtually all tissues in the body. The size and form of hyaluronan present in tissues is indicative of a healthy or inflamed tissue, and the interactions of hyaluronan with immune cells can influence their response. Thus in order to understand how inflammation is regulated, it is necessary to understand these interactions and their consequences. Although there is a large turnover of hyaluronan in our bodies, the large molecular mass form of hyaluronan predominates in healthy tissues. Upon tissue damage and/or infection, the ECM and hyaluronan are broken down and an inflammatory response ensues. As inflammation is resolved, the ECM is restored and high molecular mass hyaluronan predominates again. Immune cells encounter hyaluronan in the tissues and lymphoid organs and respond differently to high and low molecular mass forms. Immune cells differ in their ability to bind hyaluronan and this can vary with the cell type and their activation state. For example, peritoneal macrophages do not bind soluble hyaluronan but can be induced to bind after exposure to inflammatory stimuli. Likewise, naïve T cells, which typically express low levels of CD44, the hyaluronan receptor, do not bind hyaluronan until they undergo antigen-stimulated T cell proliferation and upregulate CD44. Despite substantial knowledge of where and when immune cells bind hyaluronan, why immune cells bind hyaluronan remains a major outstanding question. Here, we review what is currently known about the interactions of hyaluronan with immune cells in both healthy and inflamed tissues and discuss how hyaluronan binding by immune cells influences the inflammatory response.

  4. The where, when, how, and why of hyaluronan binding by immune cells.

    Science.gov (United States)

    Lee-Sayer, Sally S M; Dong, Yifei; Arif, Arif A; Olsson, Mia; Brown, Kelly L; Johnson, Pauline

    2015-01-01

    Hyaluronan is made and extruded from cells to form a pericellular or extracellular matrix (ECM) and is present in virtually all tissues in the body. The size and form of hyaluronan present in tissues are indicative of a healthy or inflamed tissue, and the interactions of hyaluronan with immune cells can influence their response. Thus, in order to understand how inflammation is regulated, it is necessary to understand these interactions and their consequences. Although there is a large turnover of hyaluronan in our bodies, the large molecular mass form of hyaluronan predominates in healthy tissues. Upon tissue damage and/or infection, the ECM and hyaluronan are broken down and an inflammatory response ensues. As inflammation is resolved, the ECM is restored, and high molecular mass hyaluronan predominates again. Immune cells encounter hyaluronan in the tissues and lymphoid organs and respond differently to high and low molecular mass forms. Immune cells differ in their ability to bind hyaluronan and this can vary with the cell type and their activation state. For example, peritoneal macrophages do not bind soluble hyaluronan but can be induced to bind after exposure to inflammatory stimuli. Likewise, naïve T cells, which typically express low levels of the hyaluronan receptor, CD44, do not bind hyaluronan until they undergo antigen-stimulated T cell proliferation and upregulate CD44. Despite substantial knowledge of where and when immune cells bind hyaluronan, why immune cells bind hyaluronan remains a major outstanding question. Here, we review what is currently known about the interactions of hyaluronan with immune cells in both healthy and inflamed tissues and discuss how hyaluronan binding by immune cells influences the inflammatory response.

  5. [Larval stages of Ascaris lumbricoides: hyaluronan-binding capacity].

    Science.gov (United States)

    Ponce-León, Patricia; Foresto, Patricia; Valverde, Juana

    2009-03-01

    Hyaluronic acid has important functions in inflammatory and tissue reparation processes. Owing to the varied strategies of the parasites to evade the host's immune response, as well as the multiple functions and physiological importance of hyaluronic acid, the aim was to study the hyaluronan binding capacity by Ascaris lumbricoides larval stages. Larval concentrates were prepared by hatching A. lumbricoides eggs. The larvae were collected by the Baermann method. The test of serum soluble CD44 detection by Agregation Inhibition was modified. All the larval concentrates presented hyaluronan binding capacity. The obtained results allow to suppose the existence of an hyaluronic acid specific receptor in A. lumbricoides. This receptor eventually might compete with the usual receptors of the host. The parasite might use this mechanism to evade the immune response.

  6. Mannose reduces hyaluronan and leukocytes in wound granulation tissue and inhibits migration and hyaluronan-dependent monocyte binding.

    Science.gov (United States)

    Jokela, Tiina A; Kuokkanen, Jukka; Kärnä, Riikka; Pasonen-Seppänen, Sanna; Rilla, Kirsi; Kössi, Jyrki; Laato, Matti; Tammi, Raija H; Tammi, Markku I

    2013-01-01

    Wound healing is a highly regulated process starting from coagulation and ending in tissue remodeling. The end result varies from perfectly restored tissue, such as in early fetal skin, to scars in adults. The balanced repair process is frequently disturbed by local or systemic factors, like infections and diabetes. A rapid increase of hyaluronan is an inherent feature of wounds and is associated with tissue swelling, epithelial and mesenchymal cell migration and proliferation, and induction of cytokine signaling. Hyaluronan extending from cell surface into structures called cables can trap leukocytes and platelets and change their functions. All these features of hyaluronan modulate inflammation. The present data show that mannose, a recently described inhibitor of hyaluronan synthesis, inhibits dermal fibroblast invasion and prevents the enhanced leukocyte binding to hyaluronan that takes place in cells treated with an inflammatory mediator interleukin-1β. Mannose also reduced hyaluronan in subcutaneous sponge granulation tissue, a model of skin wound, and suppressed its leukocyte recruitment and tissue growth. Mannose thus seems to suppress wounding-induced inflammation in skin by attenuating hyaluronan synthesis.

  7. Hyaluronan binding motifs of USP17 and SDS3 exhibit anti-tumor activity.

    Directory of Open Access Journals (Sweden)

    Suresh Ramakrishna

    Full Text Available BACKGROUND: We previously reported that the USP17 deubiquitinating enzyme having hyaluronan binding motifs (HABMs interacts with human SDS3 (suppressor of defective silencing 3 and specifically deubiquitinates Lys-63 branched polyubiquitination of SDS3 resulting in negative regulation of histone deacetylase (HDAC activity in cancer cells. Furthermore, USP17 and SDS3 mutually interact with each other to block cell proliferation in HeLa cells but the mechanism for this inhibition in cell proliferation is not known. We wished to investigate whether the HABMs of USP17 were responsible for tumor suppression activity. METHODOLOGY/PRINCIPAL FINDINGS: Similarly to USP17, we have identified that SDS3 also has three consecutive HABMs and shows direct binding with hyaluronan (HA using cetylpyridinium chloride (CPC assay. Additionally, HA oligosaccharides (6-18 sugar units competitively block binding of endogenous HA polymer to HA binding proteins. Thus, administration of HA oligosaccharides antagonizes the interaction between HA and USP17 or SDS3. Interestingly, HABMs deleted USP17 showed lesser interaction with SDS3 but retain its deubiquitinating activity towards SDS3. The deletion of HABMs of USP17 could not alter its functional regulation on SDS3-associated HDAC activity. Furthermore, to explore whether HABMs in USP17 and SDS3 are responsible for the inhibition of cell proliferation, we investigated the effect of USP17 and SDS3-lacking HABMs on cell proliferation by soft agar, apoptosis, cell migration and cell proliferation assays. CONCLUSIONS: Our results have demonstrated that these HABMs in USP17 and its substrate SDS3 are mainly involved in the inhibition of anchorage-independent tumor growth.

  8. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor

    OpenAIRE

    Katarzyna Marchlewska; Eliza Filipiak; Renata Walczak-Jedrzejowska; Elzbieta Oszukowska; Slawomir Sobkiewicz; Malgorzata Wojt; Jacek Chmiel; Krzysztof Kula; Jolanta Slowikowska-Hilczer

    2016-01-01

    Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with...

  9. Evidence for clustered mannose as a new ligand for hyaluronan-binding protein (HABP1) from human fibroblasts

    Indian Academy of Sciences (India)

    Rajeev Kumar; Nirupam Roy Choudhury; Dinakar M Salunke; K Datta

    2001-09-01

    We have earlier reported that overexpression of the gene encoding human hyaluronan-binding protein (HABP1) is functionally active, as it binds specifically with hyaluronan (HA). In this communication, we confirm the collapse of the filamentous and branched structure of HA by interaction with increasing concentrations of recombinant-HABP1 (rHABP1). HA is the reported ligand of rHABP1. Here, we show the affinity of rHABP1 towards D-mannosylated albumin (DMA) by overlay assay and purification using a DMA affinity column. Our data suggests that DMA is another ligand for HABP1. Furthermore, we have observed that DMA inhibits the binding of HA in a concentration-dependent manner, suggesting its multiligand affinity amongst carbohydrates. rHABP1 shows differential affinity towards HA and DMA which depends on pH and ionic strength. These data suggest that affinity of rHABP1 towards different ligands is regulated by the microenvironment.

  10. Expression of hyaluronan and the hyaluronan-binding proteoglycans neurocan, aggrecan, and versican by neural stem cells and neural cells derived from embryonic stem cells.

    Science.gov (United States)

    Abaskharoun, Mary; Bellemare, Marie; Lau, Elizabeth; Margolis, Richard U

    2010-04-23

    We have examined the expression and localization patterns of hyaluronan and hyaluronan-binding chondroitin sulfate proteoglycans in neural stem cells and differentiated neural cells derived from mouse embryonic stem cells. Expression of proteoglycans and hyaluronan was weak in the SSEA1-positive embryonic stem cells but increased noticeably after retinoic acid induction to nestin-positive neural stem cells. After subsequent plating, the hyaluronan-binding chondroitin sulfate proteoglycans aggrecan, neurocan, and versican are expressed by cells in both the astrocytic and neuronal lineages. During the time period that hyaluronan was present, it co-localized with each of the hyaluronan-binding proteoglycans studied and was found to be clearly associated with beta-III tubulin-expressing neurons and oligodendrocytes expressing the O4 sulfatide marker. Although proteoglycan expression levels increased to varying degrees following neural differentiation, they did not change noticably during the following 2 weeks in culture, but there was a significant decrease in hyaluronan expression. Our studies therefore demonstrate the expression by neural stem cells and neural cells derived from them of hyaluronan and its associated proteoglycans, thereby providing a necessary foundation for integrating their specific properties into developing strategies for therapeutic applications.

  11. Bioactive hyaluronan fragment (hexasaccharide) detects specific hexa-binding proteins in human breast and stomach cancer: possible role in tumorogenesis.

    Science.gov (United States)

    Srinivas, Prashanth; Kollapalli, Srinivas Prasad; Thomas, Anil; Mortha, Karuna Kumar; Banerjee, Shib Das

    2012-08-01

    Hyaluronan (HA) is a component of extracellular matrix that influences cell-proliferation, migration, development, regeneration, normal tissue remodeling, tissues undergoing malignancy and tumor cell interaction. The widespread occurrence of HA binding proteins, their involvement in tissue organization and the control of cellular behavior are well documented. The low molecular mass HA fragments can also induce a variety of biological events, including chemokine gene expression, transcription factor expression and angiogenesis. It is believed that these fragments are more potent in cellular activities than high molecular mass HA. In this study, we isolated the various fragments by gel permeation chromatography of hyaluronidase digested HA and characterized by fluoro assisted carbohydrate electrophoresis (FACE) and matrix assisted laser desorption ionization analysis (MALDI). Detection and distribution of cellular receptors in invasive tumor tissues for HA polymer and HA fragments were determined both by Western blot and histochemistry. The study demonstrated the overexpression of HA-hexa binding protein in human tumors of breast and stomach and its involvement in tumorogenesis.

  12. Terminal sialic acids on CD44 N-glycans can block hyaluronan binding by forming competing intramolecular contacts with arginine sidechains

    Science.gov (United States)

    Faller, Christina E.; Guvench, Olgun

    2014-01-01

    Specific sugar residues and their linkages form the basis of molecular recognition for interactions of glycoproteins with other biomolecules. Seemingly small changes, like the addition of a single monosaccharide in the covalently attached glycan component of glycoproteins, can greatly affect these interactions. For instance, the sialic acid capping of glycans affects protein-ligand binding involved in cell-cell and cell-matrix interactions. CD44 is a single-pass transmembrane glycoprotein whose binding with its carbohydrate ligand hyaluronan (HA), an extracellular matrix component, mediates processes such as leukocyte homing, cell adhesion, and tumor metastasis. This binding is highly regulated by glycosylation of the N-terminal extracellular hyaluronan-binding domain (HABD); specifically, sialic acid capped N-glycans of HABD inhibit ligand binding. However, the molecular mechanism behind this sialic acid mediated regulation has remained unknown. Two of the five N-glycosyation sites of HABD have been previously identified as having the greatest inhibitory effect on HA binding, but only if the glycans contain terminal sialic acid residues. These two sites, Asn25 and Asn120, were chosen for in silico glycosylation in this study. Here, from extensive standard molecular dynamics simulations and biased simulations, we propose a molecular mechanism for this behavior based on spontaneously-formed charge-paired hydrogen bonding interactions between the negatively-charged sialic acid residues and positively-charged Arg sidechains known to be critically important for binding to HA, which itself is negatively charged. Such intramolecular hydrogen bonds would preclude associations critical to hyaluronan binding. This observation suggests how CD44 and related glycoprotein binding is regulated by sialylation as cellular environments fluctuate. PMID:25116630

  13. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor.

    Science.gov (United States)

    Marchlewska, Katarzyna; Filipiak, Eliza; Walczak-Jedrzejowska, Renata; Oszukowska, Elzbieta; Sobkiewicz, Slawomir; Wojt, Malgorzata; Chmiel, Jacek; Kula, Krzysztof; Slowikowska-Hilczer, Jolanta

    2016-01-01

    Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.

  14. Isolation and characterization of the plasma hyaluronan-binding protein (PHBP) gene (HABP2).

    Science.gov (United States)

    Sumiya, J; Asakawa, S; Tobe, T; Hashimoto, K; Saguchi, K; Choi-Miura, N H; Shimizu, Y; Minoshima, S; Shimizu, N; Tomita, M

    1997-11-01

    PHBP is a novel human plasma hyaluronan-binding protein that shows significant homology in amino acid sequence to hepatocyte growth factor activator. Two overlapping clones that encode the human plasma hyaluronan-binding protein (PHBP) gene (HABP2) were isolated and characterized. The PHBP gene spans 35 kb and is composed of 13 exons from 37 to 1,394 bp in size with consensus splice sites. The gene's regulatory sequences contain putative promoter elements, but no typical TATA box. Some exons of this gene showed significant similarities to those of coagulation factor XII, tissue-type plasminogen activator, and urokinase genes in nucleotide length and in intron phasing. We also report the chromosome mapping of this gene by fluorescence in situ hybridization (FISH) using a genomic DNA fragment as a probe. The PHBP gene (HABP2) was located on chromosome 10q25-q26.

  15. Hyaluronan- and RNA-binding deubiquitinating enzymes of USP17 family members associated with cell viability

    Directory of Open Access Journals (Sweden)

    Kim Dongku

    2006-11-01

    Full Text Available Abstract Background Protein degradation by the ubiquitin system plays a crucial role in numerous cellular signaling pathways. Deubiquitination, a reversal of ubiquitination, has been recognized as an important regulatory step in the ubiquitin-dependent degradation pathway. Results While identifying putative ubiquitin specific protease (USP enzymes that contain a conserved Asp (I domain in humans, 4 USP17 subfamily members, highly homologous to DUB-3, have been found (USP17K, USP17L, USP17M, and USP17N, from human chorionic villi. Expression analysis showed that USP17 transcripts are highly expressed in the heart, liver, and pancreas and are expressed moderately in various human cancerous cell lines. Amino acid sequence analysis revealed that they contain the highly conserved Cys, His, and Asp domains which are responsible for the deubiquitinating activity. Biochemical enzyme assays indicated that they have deubiquitinating activity. Interestingly, the sequence analysis showed that these proteins, with exception of USP17N, contain the putative hyaluronan/RNA binding motifs, and cetylpyridinium chloride (CPC-precipitation analysis confirmed the association between these proteins and intracellular hyaluronan and RNA. Conclusion Here, we report that the overexpression of these proteins, with exception of USP17N, leads to apoptosis, suggesting that the hyaluronan and RNA binding motifs in these enzymes play an important role in regulating signal transduction involved in cell death.

  16. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor

    Directory of Open Access Journals (Sweden)

    Katarzyna Marchlewska

    2016-01-01

    Full Text Available Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC and men with testicular germ cell tumor (TGCT. Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI and the ability of sperm to bind with hyaluronan (HA was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p<0.01 and a lower percentage of HA-bound sperm (24% versus 66%; p<0.001. Normal results of both analyses were observed in 24% of IC men and 4% of men with TGCT. Negative Spearman’s correlations were found between DFI and the percentage of HA-bound sperm in the whole group and in IC subjects and those with TGCT analyzed separately. Conclusions. Approximately 76% of IC men and 96% with TGCT awaiting orchiectomy demonstrated DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.

  17. Unbinding of Hyaluronan Accelerates the Enzymatic Activity of Bee Hyaluronidase

    OpenAIRE

    Iliás, Attila; Liliom, Károly; Greiderer-Kleinlercher, Brigitte; Reitinger, Stephan; Lepperdinger, Günter

    2011-01-01

    Hyaluronan (HA), a polymeric glycosaminoglycan ubiquitously present in higher animals, is hydrolyzed by hyaluronidases (HAases). Here, we used bee HAase as a model enzyme to study the HA-HAase interaction. Located in close proximity to the active center, a bulky surface loop, which appears to obstruct one end of the substrate binding groove, was found to be functionally involved in HA turnover. To better understand kinetic changes in substrate interaction, binding of high molecular weight HA ...

  18. Unbinding of Hyaluronan Accelerates the Enzymatic Acitivity of Bee Hyaluronidase

    OpenAIRE

    Iliás, A.; Greiderer-Kleinlercher, B.; Lepperdinger, G.; Liliom, K; Reitinger, S.

    2011-01-01

    Hyaluronan (HA), a polymeric glycosaminoglycan ubiquitously present in higher animals, is hydrolyzed by hyaluronidases (HAases). Here, we used bee HAase as a model enzyme to study the HA-HAase interaction. Located in close proximity to the active center, a bulky surface loop, which appears to obstruct one end of the substrate binding groove, was found to be functionally involved in HA turnover. To better understand kinetic changes in substrate interaction, binding of high molecular weight HA ...

  19. HABP2 is a novel regulator of hyaluronan-mediated human lung cancer progression

    OpenAIRE

    Tamara eMirzapoiazova; Nurbek eMambetsariev; Frances E Lennon; Bolot eMambetsariev; Joshua E. Berlind; Ravi eSalgia; Singleton, Patrick A.

    2015-01-01

    Background: Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA), which we have previously demonstrated can regulate the activity of the extracellular serine protease, Hyaluronan Binding Protein 2 (HABP2). This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics.Methods: Immunohistochemical analysis was...

  20. HABP2 is a Novel Regulator of Hyaluronan-Mediated Human Lung Cancer Progression

    OpenAIRE

    Mirzapoiazova, Tamara; Mambetsariev, Nurbek; Frances E Lennon; Mambetsariev, Bolot; Joshua E. Berlind; Salgia, Ravi; Singleton, Patrick A.

    2015-01-01

    Background Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA), which we have previously demonstrated can regulate the activity of the extracellular serine protease, hyaluronan binding protein 2 (HABP2). This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics. Methods Immunohistochemical an...

  1. Developing Fluorescent Hyaluronan Analogs for Hyaluronan Studies

    Directory of Open Access Journals (Sweden)

    Shi Ke

    2012-02-01

    Full Text Available Two kinds of fluorescent hyaluronan (HA analogs, one serving as normal imaging agent and the other used as a biosensitive contrast agent, were developed for the investigation of HA uptake and degradation. Our approach of developing HA imaging agents depends on labeling HA with varying molar percentages of a near-infrared (NIR dye. At low labeling ratios, the hyaluronan uptake can be directly imaged while at high labeling ratios, the fluorescent signal is quenched and signal generation occurs only after degradation. It is found that the conjugate containing 1%–2% NIR dye can be used as a normal optical imaging agent, while bioactivable imaging agents are formed at 6% to 17% dye loading. It was determined that the conjugation of dye to HA with different loading percentages does not impact HA biodegradation by hyaluronidase (Hyal. The feasibility of using these two NIR fluorescent hyaluronan analogs for HA investigation was evaluated in vivo with optical imaging. The data demonstrates that the 1% dye loaded fluorescent HA can be used to monitor the behavior of HA and its fragments, whereas bioactivatable HA imaging agent (17% dye in HA is more suitable for detecting HA fragments.

  2. Conformational Analysis of the Streptococcus pneumoniae Hyaluronate Lyase and Characterization of Its Hyaluronan-specific Carbohydrate-binding Module*

    Science.gov (United States)

    Suits, Michael D. L.; Pluvinage, Benjamin; Law, Adrienne; Liu, Yan; Palma, Angelina S.; Chai, Wengang; Feizi, Ten; Boraston, Alisdair B.

    2014-01-01

    For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a β-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl. PMID:25100731

  3. Golgi localization and dynamics of hyaluronan binding protein 1 (HABP1/p32/C1QBP) during the cell cycle

    Institute of Scientific and Technical Information of China (English)

    Aniruddha SENGUPTA; Bhaswati BANERJEE; Rakesh K. TYAGI; Kasturi DATTA

    2005-01-01

    Hyaluronan binding protein 1 (HABP1) is a negatively charged multifunctional mammalian protein with a unique structural fold. Despite the fact that HABP1 possesses mitochondrial localization signal, it has also been localized to other cellular compartments. Using indirect immunofluorescence, we examined the sub-cellular localization of HABP1 and its dynamics during mitosis. We wanted to determine whether it distributes in any distinctive manner after mitotic nuclear envelope disassembly or is dispersed randomly throughout the cell. Our results reveal the golgi localization of HABP1 and demonstrate its complete dispersion throughout the cell during mitosis. This distinctive distribution pattern of HABP1 during mitosis resembles its ligand hyaluronan, suggesting that in concert with each other the two molecules play critical roles in this dynamic process.

  4. Interactions between CD44 and hyaluronan in leukocyte trafficking

    Directory of Open Access Journals (Sweden)

    Braedon eMcDonald

    2015-02-01

    Full Text Available Recruitment of leukocytes from the bloodstream to inflamed tissues requires a carefully regulated cascade of binding interactions between adhesion molecules on leukocytes and endothelial cells. Adhesive interactions between CD44 and hyaluronan have been implicated in the regulation of immune cell trafficking within various tissues. In this review, the biology of CD44-hyaluronan interactions in cell trafficking is summarized, with special attention to neutrophil recruitment within the liver microcirculation. We describe the molecular mechanisms that regulate adhesion between neutrophil CD44 and endothelial hyaluronan, including recent evidence implicating serum-derived hyaluronan associated protein (SHAP as an important co-factor in the binding of hyaluronan to CD44 under flow conditions. CD44-hyaluronan mediated neutrophil recruitment has been shown to contribute to innate immune responses to invading microbes, as well as to the pathogenesis of many inflammatory diseases, including various liver pathologies. As a result, blockade of neutrophil recruitment by targeting CD44-HA interactions has proven beneficial as an anti-inflammatory treatment strategy in a number of animal models of inflammatory diseases.

  5. Overexpression of Hyaluronan-binding Protein 1 (HABP1/p32/gC1qR) in HepG2 Cells Leads to Increased Hyaluronan Synthesis and Cell Proliferation by Up-regulation of Cyclin D1 in AKT-dependent Pathway*

    Science.gov (United States)

    Kaul, Rachna; Saha, Paramita; Saradhi, Mallampati; Prasad, Ramachandra L. A.; Chatterjee, Soumya; Ghosh, Ilora; Tyagi, Rakesh K.; Datta, Kasturi

    2012-01-01

    Overexpression of the mature form of hyaluronan-binding protein 1 (HABP1/gC1qR/p32), a ubiquitous multifunctional protein involved in cellular signaling, in normal murine fibroblast cells leads to enhanced generation of reactive oxygen species (ROS), mitochondrial dysfunction, and ultimately apoptosis with the release of cytochrome c. In the present study, human liver cancer cell line HepG2, having high intracellular antioxidant levels was chosen for stable overexpression of HABP1. The stable transformant of HepG2, overexpressing HABP1 does not lead to ROS generation, cellular stress, and apoptosis, rather it induced enhanced cell growth and proliferation over longer periods. Phenotypic changes in the stable transformant were associated with the increased “HA pool,” formation of the “HA cable” structure, up-regulation of HA synthase-2, and CD44, a receptor for HA. Enhanced cell survival was further supported by activation of MAP kinase and AKT-mediated cell survival pathways, which leads to an increase in CYCLIN D1 promoter activity. Compared with its parent counterpart HepG2, the stable transformant showed enhanced tumorigenicity as evident by its sustained growth in low serum conditions, formation of the HA cable structure, increased anchorage-independent growth, and cell-cell adhesion. This study suggests that overexpression of HABP1 in HepG2 cells leads to enhanced cell survival and tumorigenicity by activating HA-mediated cell survival pathways. PMID:22451658

  6. Are sperm DNA fragmentation, hyperactivation, and hyaluronan-binding ability predictive for fertilization and embryo development in in vitro fertilization and intracytoplasmic sperm injection?

    Science.gov (United States)

    Pregl Breznik, Barbara; Kovačič, Borut; Vlaisavljević, Veljko

    2013-04-01

    To determine the diagnostic value of the following sperm function tests in predicting the fertilizing ability of spermatozoa in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI): hyaluronan-binding assay (HBA), DNA fragmentation (Halosperm), and hyperactivity. Prospective study. University medical center. 133 couples undergoing infertility treatment with IVF/ICSI. Analysis of sperm DNA fragmentation, hyaluronan-binding ability, and hyperactivation on washed semen samples used for the insemination of oocytes. Correlation between the results of sperm function tests and the fertilization rate (FR) or embryo quality (EQ) after IVF and ICSI. Comparison of the sperm DNA fragmentation, hyperactivation, and hyaluronan binding ability between cycles with less than 50% (group 1) and more than 50% (group 2) of oocytes fertilized after IVF. Both FR and EQ in IVF cycles negatively correlated with sperm DNA fragmentation. Furthermore, a positive correlation was observed between FR and hyaluronan-binding ability or induced hyperactivity. The semen samples from the IVF cycles with low FR (group 1) were characterized by statistically significantly higher sperm DNA fragmentation and lower hyaluronan-binding ability in comparison with semen samples from the group with high levels of fertilization (group 2). In ICSI cycles, no relationship was found between sperm function tests and FR or EQ. The Halosperm test, the HBA test, and induced hyperactivity are useful in predicting the ability of spermatozoa to fertilize oocytes in IVF and are helpful in distinguishing semen samples suitable for IVF or ICSI. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. Vitrification is not superior to rapid freezing of normozoospermic spermatozoa: effects on sperm parameters, DNA fragmentation and hyaluronan binding.

    Science.gov (United States)

    Agha-Rahimi, Azam; Khalili, Mohammad Ali; Nabi, Ali; Ashourzadeh, Sareh

    2014-03-01

    Human sperm vitrification is a new cryopreservation method. This study compared the effects of rapid freezing and vitrification on various sperm parameters, hyaluronan-binding assay and DNA fragmentation and assessed the impact of cryoprotectant agents (CPA) with vitrification. A total of 30 normo-ejaculates were prepared by swim up and the motile sperm fraction was divided into four: fresh (control), rapid freezing, and two vitrification groups (a, lacking CPA; b, with CPA). For rapid freezing, a cryovial of sperm suspension was held just above the liquid nitrogen surface, and for vitrification, 30μl suspension was dropped directly into liquid nitrogen. Sperm parameters, including motility, viability and morphology, declined after cryopreservation in both groups. DNA fragmentation was not significantly higher in the vitrification (15.7±4.4%) or rapid freezing (16.6±5.6%) groups when compared with controls (11.6±4.5%). The rates of hyaluronan binding were similar between the control and cryopreserved groups. Moreover, addition of CPA for vitrification had a neutral effect on rates of sperm recovery. In conclusion, vitrification has great potential for human sperm cryopreservation and does not require CPA, with its possible toxicity. However, it is not superior to rapid cryopreservation regarding sperm recovery rate in normozoospermia. Human sperm vitrification is a new cryopreservation method that has been introduced recently. This study compared the effects of rapid freezing with vitrification on rates of sperm parameters, hyaluronan-binding assay and DNA fragmentation after thawing/warming and assessed the impact of cryoprotectant agent (CPA) on vitrification. The study was performed on 30 ejaculates prepared using the swim-up technique. Each motile sperm suspension was divided into four: control (fresh); rapid freezing; and two vitrification groups (a, lacking CPA; b, with CPA). For rapid freezing, a cryovial of sperm suspension was held above the surface of

  8. Increased Hyaluronan Acid Binding Ability of Spermatozoa Indicating a Better Maturity, Morphology, and Higher DNA Integrity After Micronutrient Supplementation

    Directory of Open Access Journals (Sweden)

    Markus Lipovac

    2014-05-01

    Full Text Available Measuring the hyaluronan-binding ability of spermatozoa is useful in predicting the ability of spermatozoa to fertilise oocytes during in vitro fertilisation (IVF. Recent publications discuss an influence of micronutrients on sperm quality. The objective of this paper was to evaluate the effect of a non-prescription nutraceutical containing eight micronutrients on sperm-hyaluronan binding assay (SHBA values among males with idiopathic sub-/infertility, using an open comparative pilot study. The study took place at the Outpatient Fertility Centre IMI, Vienna, Austria, and involved 67 sub-/infertile males. Sub-/infertile males were invited to participate and take two daily capsules of the active compound for a 3-month period between the first and the follow-up semen analysis. Each capsule contained L-carnitine, L-arginine, zinc, vitamin E, glutathione, selenium, coenzyme Q10 (CoQ10, and folic acid (Profertil®. 40 sub-/infertile men receiving no active treatment served as controls; this was measured by change in SHBA after 3 months. It was found that SHBA values significantly increased after 3 months of treatment with the active compound, from a median baseline value of 56.0% to 74% (p<0.05. This represented a 19.7% increase compared to baseline, which was significantly higher than the 2.1% decrease observed in the control group. The rate of subjects displaying an increase in SHBA values after 3 months was significantly higher in the active group (74.6% versus 30.0%, p=0.0001, which showed that sub-/infertile men treated with the active micronutrient compound displayed increased SHBA ability. However, more research is necessary to get detailed information on this specific subject.

  9. Doxorubicin-Hyaluronan Conjugated Super-Paramagnetic Iron Oxide Nanoparticles (DOX-HA-SPION) Enhanced Cytoplasmic Uptake of Doxorubicin and Modulated Apoptosis, IL-6 Release and NF-kappaB Activity in Human MDA-MB-231 Breast Cancer Cells.

    Science.gov (United States)

    Vyas, Dinesh; Lopez-Hisijos, Nicolas; Gandhi, Sulakshana; El-Dakdouki, M; Basson, Marc D; Walsh, Mary F; Huang, X; Vyas, Arpita K; Chaturvedi, Lakshmi S

    2015-09-01

    Triple negative breast cancer exhibit increased IL-6 expression compared with matched healthy breast tissue and a strong link between inflammation and cancer progression and metastasis has been reported. We investigated whether doxorubicin-hyaluronan-super-paramagnetic iron oxide nanoparticles (DOX-HA-SPION) would show greater therapeutic efficacy in human triple negative breast cancer cells (TNBC) MDA-MB-231, as was recently shown in drug-sensitive and multi-drug-resistant ovarian cancer cells. Therefore, we measured cellular DOX uptake via confocal microscopy; observed morphologic changes: mitochondrial and nuclear changes with electron microscopy, and quantitated apoptosis using FACS analysis after Annexin V and PI staining in MDA-MB-231 cells treated with either DOX alone or DOX-HA-SPION. We also measured both proinflammatory and anti-inflammatory cytokines; IL-6, IL-10 respectively and also measured nitrate levels in the conditioned medium by ELISA. Inaddition, NF-κB activity was measured by luciferase assay. Confocal microscopy demonstrated greater cytoplasmic uptake of DOX-HA-SPION than free DOX. We also demonstrated reduction of Vimentin with DOX-HA-SPION which is significantly less than both control and DOX. DOX-HA-SPION enhanced apoptosis and significantly down regulated both pro-inflammatory mediators IL-6 and NF-κB in comparison to DOX alone. The secretion levels of anti-inflammatory mediators IL-10 and nitrate was not decreased in the DOX or DOX-HA-SPION treatment groups. Our data suggest that DOX-HA-SPION nanomedicine-based drug delivery could have promising potential in treating metastasized and chemoresistant breast cancer by enhancing the drug efficacy and minimizing off-target effects.

  10. Biology of hyaluronan: Insights from genetic disorders of hyaluronan metabolism

    Institute of Scientific and Technical Information of China (English)

    Barbara; Triggs-Raine; Marvin; R; Natowicz

    2015-01-01

    Hyaluronan is a rapidly turned over component of the vertebrate extracellular matrix. Its levels are determined, in part, by the hyaluronan synthases, HAS1, HAS2, and HAS3, and three hyaluronidases, HYAL1, HYAL2 and HYAL3. Hyaluronan binding proteins also regulate hyaluronan levels although their involvement is less well understood. To date, two genetic disorders of hyaluronan metabolism have been reported in humans: HYAL1 deficiency(Mucopolysaccharidosis IX) in four individuals with joint pathology as the predominant phenotypic finding and HAS2 deficiency in a single person having cardiac pathology. However, inherited disorders and induced mutations affecting hyaluronan metabolism have been characterized in other species. Overproduction of hyaluronan by HAS2 results in skin folding and thickening in shar-pei dogs and the naked mole rat, whereas a complete deficiency of HAS2 causes embryonic lethality in mice due to cardiac defects. Deficiencies of murine HAS1 and HAS3 result in a predisposition to seizures. Like humans, mice with HYAL1 deficiency exhibit joint pathology. Mice lacking HYAL2 have variably penetrant developmental defects, including skeletal and cardiac anomalies. Thus, based on mutant animal models, a partial deficiency of HAS2 or HYAL2 might be compatible with survival in humans, while complete deficiencies of HAS1, HAS3, and HYAL3 may yet be recognized.

  11. Molecular cloning and tissue distribution of hyaluronan binding protein 2 (HABP2) in red sea bream Pagrus major.

    Science.gov (United States)

    Yoshida, Asami; Wang, Yajun; Bae, Inwoo; Cao, Min-Jie; Osatomi, Kiyoshi; Hara, Kenji

    2013-08-01

    Previously we have isolated a novel gelatinolytic serine proteinase, named G1, from the muscle and the plasma of red sea bream. In order to clarify the structure and function of G1, we cloned the full-length cDNA of G1 from the hepatopancreas of red sea bream. G1 cDNA encoded 633 amino acids with a secretory signal sequence at N-terminus, three epidermal growth factor-like domains, a kringle domain, and a trypsin-like serine protease domain. The active site residues of a serine proteinase were conserved in the serine protease domain of G1. The tissue distributions of the mRNA and gelatinolytic activity of G1 were investigated using RT-PCR and gelatin zymography, respectively. Its activity was detected in various tissues while the mRNA of it was strongly expressed in the hepatopancreas. These results suggest that G1 is synthesized in hepatopancreas and carried to the muscle, kidney, heart and ovary via the bloodstream in the red sea bream. The enzyme has a similar domain structure and tissue distribution to those of human hyaluronan binding protein 2 (HABP2) engaged in the extracellular matrix (ECM) turnover. Thus, it is suggested that G1 is identified as HABP2 and is possibly involved in ECM proteolysis of red sea bream.

  12. Variation in hyaluronan-binding protein 2 (HABP2) promoter region is associated with unexplained female infertility.

    Science.gov (United States)

    Altmäe, Signe; Kallak, Theodora Kunovac; Fridén, Barbo; Stavreus-Evers, Anneli

    2011-05-01

    We set up to analyze polymorphisms in hyaluronan-binding protein 2 (HABP2) gene in healthy fertile women (n = 158) and in women with unexplained infertility (n = 116) and to investigate the potential role of HABP2 in receptive endometrium. Minor rs1157916 A and the major rs2240879 A alleles together with AA genotypes were significantly less frequent in infertile women than in controls. Immunohistochemistry analysis of endometrial HABP2 expression at the time of implantation identified significantly lower HABP2 protein level in infertile women in stroma and vessels than in fertile women. Migration assay analysis of cultured trophoblast and endothelial cells toward HABP2 protein referred to the function of HABP2 in endometrial endothelial cells. In conclusion, our results indicate that polymorphisms in the regulatory region of HABP2 gene could influence gene expression levels in the receptive endometrium and could thereby be one reason for infertility complications in women with unexplained infertility. Additionally, HABP2 protein involvement in endometrial angiogenesis is proposed.

  13. Hyaluronan in human malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Sironen, R.K. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Tammi, M.; Tammi, R. [Institute of Biomedicine, Anatomy, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Auvinen, P.K. [Department of Oncology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Anttila, M. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Gynecology and Obstetrics, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Kosma, V-M., E-mail: Veli-Matti.Kosma@uef.fi [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland)

    2011-02-15

    Hyaluronan, a major macropolysaccharide in the extracellular matrix of connective tissues, is intimately involved in the biology of cancer. Hyaluronan accumulates into the stroma of various human tumors and modulates intracellular signaling pathways, cell proliferation, motility and invasive properties of malignant cells. Experimental and clinicopathological evidence highlights the importance of hyaluronan in tumor growth and metastasis. A high stromal hyaluronan content is associated with poorly differentiated tumors and aggressive clinical behavior in human adenocarcinomas. Instead, the squamous cell carcinomas and malignant melanomas tend to have a reduced hyaluronan content. In addition to the stroma-cancer cell interaction, hyaluronan can influence stromal cell recruitment, tumor angiogenesis and epithelial-mesenchymal transition. Hyaluronan receptors, hyaluronan synthases and hyaluronan degrading enzymes, hyaluronidases, are involved in the modulation of cancer progression, depending on the tumor type. Furthermore, intracellular signaling and angiogenesis are affected by the degradation products of hyaluronan. Hyaluronan has also therapeutic implications since it is involved in multidrug resistance.

  14. Intermediate heparan sulfate binding during HPV-16 infection in HaCaTs.

    Science.gov (United States)

    Kumar, Annandita; Jacob, Taylor; Abban, Cynthia Y; Meneses, Patricio I

    2014-01-01

    Human papillomavirus (HPV) is the most prevalent sexually transmitted disease in the United States and can cause cancer with persistent infection. The most common cancer caused by HPV is cervical carcinoma with an average of 12,000 cases reported every year in the United States. Worldwide, over 500,000 cases of cervical cancer are reported yearly with over 250,000 deaths attributed to the disease. Although much is known about the serious health risks associated with HPV infection, there is still much to be discovered about how HPV binds and enters target cells. Understanding is required on how HPV infections will lead to strategies and therapies for reducing the number of infections and HPV-related diseases, including cancers. The HPV viral particle is composed of 2 viral proteins, L1 and L2. Data suggest that binding of the viral capsid to cells is dependent on the L1 protein. We hypothesize that this initial binding to a heparan sulfate is composed of 2 independent events: the first results in a structural change that exposes a hidden portion of the L1 protein leading to a second binding event on the heparan sulfate. Our experiments tested if this "hidden" portion of L1 is necessary for infection and explored the nature of this binding. We generated a peptide with the sequence of the "hidden" portion of L1. Infection of HaCaT cells in the presence of this peptide is highly reduced. Our results suggest that the binding of the L1 C-terminal domain is dependent on amino acid sequence and is necessary for infection.

  15. Hyaluronan: from biomimetic to industrial business strategy.

    Science.gov (United States)

    Murano, Erminio; Perin, Danilo; Khan, Riaz; Bergamin, Massimo

    2011-04-01

    Hyaluronan (hyaluronic acid) is a naturally occurring polysaccharide of a linear repeating disaccharide unit consisting of beta-(1-->4)-linked D-glucopyranuronic acid and beta-(1-->3)-linked 2-acetamido-2-deoxy-D-glucopyranose, which is present in extracellular matrices, the synovial fluid of joints, and scaffolding that comprises cartilage. In its mechanism of synthesis, its size, and its physico-chemical properties, hyaluronan is unique amongst other glycosaminoglycans. The network-forming, viscoelastic and its charge characteristics are important to many biochemical properties of living tissues. It is an important pericellular and cell surface constituent; its interaction with other macromolecules such as proteins, participates in regulating cell behavior during numerous morphogenic, restorative, and pathological processes in the body. The knowledge of HA in diseases such as various forms of cancers, arthritis and osteoporosis has led to new impetus in research and development in the preparation of biomaterials for surgical implants and drug conjugates for targeted delivery. A concise and focused review on hyaluronan is timely. This review will cover the following important aspects of hyaluronan: (i) biological functions and synthesis in nature; (ii) current industrial production and potential biosynthetic processes of hyaluronan; (iii) chemical modifications of hyaluronan leading to products of commercial significance; and (iv) and the global market position and manufacturers of hyaluronan.

  16. Expression of hyaluronan synthases and corresponding hyaluronan receptors is differentially regulated during oocyte maturation in cattle.

    Science.gov (United States)

    Schoenfelder, Martin; Einspanier, Ralf

    2003-07-01

    In response to the gonadotropin surge, the compact cumulus-oocyte complex (COC) undergoes expansion by synthesis of the mucopolysaccharide hyaluronan (HA) accompanying oocyte maturation. The objective of the present study was to quantify mRNA transcripts of the HA synthase (HAS) 1, HAS2, and HAS3 and the HA-receptors CD44 and RHAMM (receptor for HA-mediated motility). Additionally, we determined the histological localization of HA and its receptor, CD44, in maturing bovine COCs and cultured granulosa cells (GCs). Full-length transcript of bovine HAS2 and a part of the bovine RHAMM sequence has been made available. Real-time reverse transcriptase-polymerase chain reaction was used for individual mRNA expressions of bovine COCs in comparison to follicular GC gonadotropin treatment. Localization of CD44 and HA were done by immunohistochemistry and biotinylated HA-binding protein, respectively. Gonadotropins caused a rapid, 120-fold increase of HAS2 mRNA, whereas a delayed, 2-fold up-regulation of HAS3 mRNA was observed. The HAS1 transcripts were barely detected. Expression of CD44 mRNA greatly increased during in vitro maturation of COCs, indicating an important role when compared to an unchanged, steady-state RHAMM expression. As a consequence, HA was locally enriched after COC expansion, but only limited change was observed in the GCs. In cultured GCs, HAS2 expression was stimulated through FSH application, followed by the effective treatments of FSH+LH and LH. Treatment with LH induced the highest increase of the CD44 receptor, followed by FSH and FSH+LH treatments. These results suggest that HAS2 is mainly responsible for rapid HA synthesis in bovine COCs and GCs. In bovine COCs, the transcriptional up-regulation of both HAS2 and the receptor CD44 appear to be important prerequisites for initiating HA-mediated effects during final oocyte development and sperm-egg interaction.

  17. Carcinoma Cell Hyaluronan as a "Portable" Cancerized Prometastatic Microenvironment.

    Science.gov (United States)

    Turley, Eva A; Wood, David K; McCarthy, James B

    2016-05-01

    Hyaluronan (HA) is a structurally simple polysaccharide, but its ability to act as a template for organizing pericellular matrices and its regulated synthesis and degradation are key to initiating repair responses. Importantly, these HA functions are usurped by tumor cells to facilitate progression and metastasis. Recent advances have identified the functional complexities associated with the synthesis and degradation of HA-rich matrices. Three enzymes synthesize large HA polymers while multiple hyaluronidases or tissue free radicals degrade these into smaller bioactive fragments. A family of extracellular and cell-associated HA-binding proteins/receptors translates the bioinformation encrypted in this complex polymer mixture to activate signaling networks required for cell survival, proliferation, and migration in an actively remodeling microenvironment. Changes in HA metabolism within both the peritumor stroma and parenchyma are linked to tumor initiation, progression, and poor clinical outcome. We review evidence that metastatic tumor cells must acquire the capability to autonomously synthesize, assemble, and process their own "portable" HA-rich microenvironments to survive in the circulation, metastasize to ectopic sites, and escape therapeutic intervention. Strategies to disrupt the HA machinery of primary tumor and circulating tumor cells may enhance the effectiveness of current conventional and targeted therapies. Cancer Res; 76(9); 2507-12. ©2016 AACR.

  18. Characterization of Palytoxin Binding to HaCaT Cells Using a Monoclonal Anti-Palytoxin Antibody

    Directory of Open Access Journals (Sweden)

    Chiara Florio

    2013-02-01

    Full Text Available Palytoxin (PLTX is the reference compound for a group of potent marine biotoxins, for which the molecular target is Na+/K+-ATPase. Indeed, ouabain (OUA, a potent blocker of the pump, is used to inhibit some PLTX effects in vitro. However, in an effort to explain incomplete inhibition of PLTX cytotoxicity, some studies suggest the possibility of two different binding sites on Na+/K+-ATPase. Hence, this study was performed to characterize PLTX binding to intact HaCaT keratinocytes and to investigate the ability of OUA to compete for this binding. PLTX binding to HaCaT cells was demonstrated by immunocytochemical analysis after 10 min exposure. An anti-PLTX monoclonal antibody-based ELISA showed that the binding was saturable and reversible, with a Kd of 3 × 10−10 M. However, kinetic experiments revealed that PLTX binding dissociation was incomplete, suggesting an additional, OUA-insensitive, PLTX binding site. Competitive experiments suggested that OUA acts as a negative allosteric modulator against high PLTX concentrations (0.3–1.0 × 10−7 M and possibly as a non-competitive antagonist against low PLTX concentrations (0.1–3.0 × 10−9 M. Antagonism was supported by PLTX cytotoxicity inhibition at OUA concentrations that displaced PLTX binding (1 × 10−5 M. However, this inhibition was incomplete, supporting the existence of both OUA-sensitive and -insensitive PLTX binding sites.

  19. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H

    Directory of Open Access Journals (Sweden)

    Guorui Yao

    2017-03-01

    Full Text Available Botulinum neurotoxins (BoNTs, which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A–G, a new mosaic toxin type termed BoNT/HA (aka type FA or H was reported recently. Sequence analyses indicate that the receptor-binding domain (HC of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2 that target the HC. Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-HC at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG and synaptic vesicle glycoprotein 2 (SV2. Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures.

  20. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Guorui; Lam, Kwok-ho; Perry, Kay; Weisemann, Jasmin; Rummel, Andreas; Jin, Rongsheng (Cornell); (Dusseldorf); (UCI)

    2017-03-01

    Botulinum neurotoxins (BoNTs), which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A–G), a new mosaic toxin type termed BoNT/HA (aka type FA or H) was reported recently. Sequence analyses indicate that the receptor-binding domain (HC) of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2) that target the HC. Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-HC at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures

  1. Adequacy of hyaluronan binding assay and a new fertility index derived from it for measuring of male fertility potential and the efficacy of supplement therapy.

    Science.gov (United States)

    Szucs, M; Osvath, P; Laczko, I; Jakab, A

    2015-06-01

    The aim of the study was to statistically prove that the HBA(®) test is an efficient practical method for andrologists to determine the fertility potential as well as to measure the efficiency of oral supplement therapy in case of male infertility. In the study, 175 patients were involved and it also included the follow-up studies of 39 patients after supplement therapy. Completing the 'classic' spermatological parameters with the results of HBA(®) test, the authors have also determined a new fertility index to be used for practical rating of the measure of fertility potential. After the supplement therapy, both sperm density and hyaluronan binding capacity increased significantly. The authors are convinced that the HBA(®) analysis is an objective, standardisable test, which provides a better approach to fertility potential. This analysis enables us to detect spermatozoa that were previously misjudged as normal by morphological assay and also makes the efficiency of the therapy more measurable. © 2014 Blackwell Verlag GmbH.

  2. Production Methods for Hyaluronan

    Directory of Open Access Journals (Sweden)

    Carmen G. Boeriu

    2013-01-01

    Full Text Available Hyaluronan is a polysaccharide with multiple functions in the human body being involved in creating flexible and protective layers in tissues and in many signalling pathways during embryonic development, wound healing, inflammation, and cancer. Hyaluronan is an important component of active pharmaceutical ingredients for treatment of, for example, arthritis and osteoarthritis, and its commercial value far exceeds that of other microbial extracellular polysaccharides. Traditionally hyaluronan is extracted from animal waste which is a well-established process now. However, biotechnological synthesis of biopolymers provides a wealth of new possibilities. Therefore, genetic/metabolic engineering has been applied in the area of tailor-made hyaluronan synthesis. Another approach is the controlled artificial (in vitro synthesis of hyaluronan by enzymes. Advantage of using microbial and enzymatic synthesis for hyaluronan production is the simpler downstream processing and a reduced risk of viral contamination. In this paper an overview of the different methods used to produce hyaluronan is presented. Emphasis is on the advancements made in the field of the synthesis of bioengineered hyaluronan.

  3. Production methods for hyaluronan

    NARCIS (Netherlands)

    Boeriu, C.G.; Springer, J.; Kooy, F.K.; Broek, van den L.A.M.; Eggink, G.

    2013-01-01

    Hyaluronan is a polysaccharide with multiple functions in the human body being involved in creating flexible and protective layers in tissues and in many signalling pathways during embryonic development, wound healing, inflammation, and cancer. Hyaluronan is an important component of active

  4. The ubiquitous hyaluronan: Functionally implicated in the oviduct?

    Science.gov (United States)

    Rodriguez-Martinez, H; Tienthai, P; Atikuzzaman, M; Vicente-Carrillo, A; Rubér, M; Alvarez-Rodriguez, M

    2016-07-01

    Hyaluronan (hyaluronic acid) is a simple, nonantigenic, nonsulfated glycosaminoglycan present everywhere in the extracellular compartments of the body. Noteworthy, it is highly conserved phylogenetically, from sauropsida to mammals; and plays a plethora of roles from embryonic/fetal development to adult physiological and pathological events, including tumor development. In reproduction, hyaluronan has proven related to initial events as sperm survival, buildup of the sperm reservoir in the oviduct, regulation of sperm capacitation, and prefertilization to later participate in embryo, fetal, and placental development. Synthesis, binding (via the CD44 membrane receptor), and degradation of hyaluronan occur in male and female genital organs, the oviduct being no exception. This review discusses our current knowledge on roles of this ubiquitous glycosaminoglycan on the survival of immunologically foreign spermatozoa in the pig oviduct, a relevant event for fertility. During preovulatory storage in the functional tubal sperm reservoir, spermatozoa are entrapped in a mucus-like tubal fluid. This fluid contains fluctuating levels of hyaluronan, which is synthesized by the lining epithelium by hyaluronan synthase 3. Both hyaluronan and its CD44 receptor are particularly evident in the deep mucosal furrows of the sperm reservoir, in which most spermatozoa are embedded in; kept alive, uncapacitated but also undetected by the immune system of the female. Hyaluronan is also present in the seminal plasma, and evidence points toward an involvement of hyaluronan and its receptor in the local (tubal and possibly uterine) production of antiinflammatory cytokines, such as interleukin-10, pertaining maternal immune tolerance of these foreign cells.

  5. 流感病毒 HA 受体结合位点抑制剂研究进展%Progress on Inhibitor Agents of Influenza Virus HA Receptor Binding Site

    Institute of Scientific and Technical Information of China (English)

    王文超; 王心竹; 尹荣焕; 赵玉军; 刘娇; 王欣; 李化生; 田菁菁

    2014-01-01

    The anti-flu drugs and flu vaccines were restricted at some time in clinic.So the influenza virus entry inhibitor agents has become the focus of current research.Sialic acid is the receptor of HA,but using sialic acid as viral entry blockers has not been successful,it indicates that sialic acid may not be an ideal scaffold for influenza virus entry inhibitor agents.The receptor binding site of HA must be exposed for binding to host sialic acid receptors,so that the receptor binding site can be monitored by the host immune system,as the potential target binding sites for antibodies.Some antibodies can bind the highly conserved amino acids on the receptor binding site of HA,that inhibits virus infection to hosts.So the antibodies tar-geting binding receptor site of HA may be the new idea for human combat influenza virus.This paper re-viewed the molecular structure and function of the influenza virus HA,mechanism of HA binding the re-ceptors,described the inhibition effect of the antibody to influenza virus entry.in order to supply help for preparation of antibodies inhibiting HA receptor binding site and research influenza virus entry inhibitor.%目前临床所用控制流感病毒的药物和疫苗受到病毒耐药性、疫苗滞后性等诸多因素的限制,使能阻止病毒侵入宿主细胞的抑制剂成为当前研究的热点。唾液酸是流感病毒囊膜表面血凝素(HA)的受体,但研究表明唾液酸并不适合作为研制流感病毒侵入宿主细胞抑制剂的结构模型。研究发现流感病毒的HA 受体结合位点必须外露才能与宿主细胞受体结合,因此 HA 受体结合位点可以被宿主免疫系统监视,成为抗体潜在的靶向契合位点。随后发现的 HA 受体结合位点抗体能与 HA 受体结合位点的保守氨基酸残基结合,能有效阻止流感病毒感染宿主。因此,可用 HA 受体结合位点抗体作为流感病毒感染抑制剂的模型,研制流感病毒抑

  6. XHAPLN3 plays a key role in cardiogenesis by maintaining the hyaluronan matrix around heart anlage.

    Science.gov (United States)

    Ito, Yuzuru; Seno, Satsuki; Nakamura, Hiroaki; Fukui, Akimasa; Asashima, Makoto

    2008-07-01

    Hyaluronan matrix plays an important role during vertebrate cardiogenesis. Transcripts for the hyaluronan synthase Has2 gene are expressed in heart anlage, and disruption of either Has2 or versican, a hyaluronan matrix component, abrogates normal cardiac morphogenesis. However, the mechanisms by which hyaluronan matrix contributes to early heart development are largely unknown. Here we show that Xenopus hyaluronan and proteoglycan-binding link protein 3 (XHAPLN3) helps to maintain hyaluronan matrix around the cardiac anlage, and thereby contribute to cardiogenesis. XHAPLN3 mRNA transcript localization overlapped with the mRNA expression of both Xhas2 and Xversican at the heart anlage of early tailbud (stage 23) embryos. Furthermore, knockdown of XHAPLN3 or Xhas2 with morpholino antisense oligos caused a heart deficiency in developing tadpoles. Our results show when and how components of the hyaluronan matrix function in cardiogenesis, improving our understanding of how extracellular matrix participates in embryogenesis.

  7. Polypeptide Grafted Hyaluronan: Synthesis and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun [ORNL; Messman, Jamie M [ORNL; Mays, Jimmy [ORNL; Baskaran, Durairaj [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Poly(L-leucine) grafted hyaluronan (HA-g-PLeu) has been synthesized via a Michael addition reaction between primary amine terminated poly(L-leucine) and acrylate-functionalized HA (TBAHA-acrylate). The precursor hyaluronan was first functionalized with acrylate groups by reaction with acryloyl chloride in the presence of triethylamine in N,N-dimethylformamide. 1H NMR analysis of the resulting product indicated that an increase in the concentration of acryloylchoride with respect to hydroxyl groups on HA has only a moderate effect on functionalization efficiency, f. A precise control of stoichiometry was not achieved, which could be attributed to partial solubility of intermolecular aggregates and the hygroscopic nature of HA. Michael addition at high [PLeu- NH2]/[acrylate]TBAHA ratios gave a molar grafting ratio of only 0.20 with respect to the repeat unit of HA, indicating grafting limitation due to insolubility of the grafted HA-g-PLeu. Soluble HA-g-PLeu graft copolymers were obtained for low grafting ratios (<0.039) with <8.6% by mass of PLeu and were characterized thoroughly using light scattering, 1H NMR, FT-IR, and AFM techniques. Light scattering experiments showed a strong hydrophobic interaction between PLeu chains, resulting in aggregates with segregated nongrafted HA segments. This yields local networks of aggregates, as demonstrated by atomic force microscopy. Circular dichroism spectroscopy showed a -sheet conformation for aggregates of poly(L-leucine).

  8. Hyaluronan within fascia in the etiology of myofascial pain.

    Science.gov (United States)

    Stecco, Carla; Stern, R; Porzionato, A; Macchi, V; Masiero, S; Stecco, A; De Caro, R

    2011-12-01

    The layers of loose connective tissue within deep fasciae were studied with particular emphasis on the histochemical distribution of hyaluronan (HA). Samples of deep fascia together with the underlying muscles were taken from neck, abdomen and thigh from three fresh non-embalmed cadavers. Samples were stained with hematoxylin-eosin, Azan-Mallory, Alcian blue and a biotinylated HA-binding protein specific for HA. An ultrasound study was also performed on 22 voluntary subjects to analyze the thickness of these deep fasciae and their sublayers. The deep fascia presented a layer of HA between fascia and the muscle and within the loose connective tissue that divided different fibrous sublayers of the deep fascia. A layer of fibroblast-like cells that stained prominently with Alcian blue stain was observed. It was postulated that these are cells specialized for the biosynthesis of the HA-rich matrix. These cells we have termed "fasciacytes", and may represent a new class of cells not previously recognized. The ultrasound study highlighted a mean thickness of 1.88 mm of the fascia lata, 1.68 mm of the rectus sheath, and 1.73 mm of the sternocleidomastoid fascia. The HA within the deep fascia facilitates the free sliding of two adjacent fibrous fascial layers, thus promoting the normal function associated with the deep fascia. If the HA assumes a more packed conformation, or more generally, if the loose connective tissue inside the fascia alters its density, the behavior of the entire deep fascia and the underlying muscle would be compromised. This, we predict, may be the basis of the common phenomenon known as "myofascial pain."

  9. HABP2 is a novel regulator of hyaluronan-mediated human lung cancer progression

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    Tamara eMirzapoiazova

    2015-07-01

    Full Text Available Background: Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA, which we have previously demonstrated can regulate the activity of the extracellular serine protease, Hyaluronan Binding Protein 2 (HABP2. This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics.Methods: Immunohistochemical analysis was performed on lung cancer patient samples using anti-HABP2 antibody. Stable control, shRNA and HABP2 overexpressing human lung adenocarcinoma cells were evaluated using immunoblot analysis, migration, extravasation and urokinase plasminogen activator (uPA activation assays with or without high molecular weight HA (HMW-HA or low molecular weight HA (LMW-HA. In human lung cancer xenograft models, primary tumor growth rates and lung metastasis were analyzed using consecutive tumor volume measurements and nestin immunoreactivity in nude mouse lungs.Results: We provide evidence that HABP2 is an important regulator of lung cancer progression. HABP2 expression was increased in several subtypes of patient non-small cell lung cancer samples. Further, HABP2 overexpression increased LMW-HA-induced uPA activation, migration and extravasation in human lung adenocarcinoma cells. In vivo, overexpression of HABP2 in human lung adenocarcinoma cells increased primary tumor growth rates in nude mice by ~2 fold and lung metastasis by ~10 fold compared to vector control cells (n=5 per condition.Conclusions: Our data suggests a possible direct effect of HABP2 on uPA activation and lung cancer progression. Our observations suggest that exploration of HABP2 in non-small cell lung carcinoma merits further study both as a diagnostic and therapeutic option.

  10. Incorporation of pentraxin 3 into hyaluronan matrices is tightly regulated and promotes matrix cross-linking.

    Science.gov (United States)

    Baranova, Natalia S; Inforzato, Antonio; Briggs, David C; Tilakaratna, Viranga; Enghild, Jan J; Thakar, Dhruv; Milner, Caroline M; Day, Anthony J; Richter, Ralf P

    2014-10-31

    Mammalian oocytes are surrounded by a highly hydrated hyaluronan (HA)-rich extracellular matrix with embedded cumulus cells, forming the cumulus cell·oocyte complex (COC) matrix. The correct assembly, stability, and mechanical properties of this matrix, which are crucial for successful ovulation, transport of the COC to the oviduct, and its fertilization, depend on the interaction between HA and specific HA-organizing proteins. Although the proteins inter-α-inhibitor (IαI), pentraxin 3 (PTX3), and TNF-stimulated gene-6 (TSG-6) have been identified as being critical for COC matrix formation, its supramolecular organization and the molecular mechanism of COC matrix stabilization remain unknown. Here we used films of end-grafted HA as a model system to investigate the molecular interactions involved in the formation and stabilization of HA matrices containing TSG-6, IαI, and PTX3. We found that PTX3 binds neither to HA alone nor to HA films containing TSG-6. This long pentraxin also failed to bind to products of the interaction between IαI, TSG-6, and HA, among which are the covalent heavy chain (HC)·HA and HC·TSG-6 complexes, despite the fact that both IαI and TSG-6 are ligands of PTX3. Interestingly, prior encounter with IαI was required for effective incorporation of PTX3 into TSG-6-loaded HA films. Moreover, we demonstrated that this ternary protein mixture made of IαI, PTX3, and TSG-6 is sufficient to promote formation of a stable (i.e. cross-linked) yet highly hydrated HA matrix. We propose that this mechanism is essential for correct assembly of the COC matrix and may also have general implications in other inflammatory processes that are associated with HA cross-linking. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Viscoelastic Properties of Hyaluronan in Physiological Conditions [version 1; referees: 2 approved

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    Mary K. Cowman

    2015-08-01

    Full Text Available Hyaluronan (HA is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM, which is particularly abundant in soft connective tissues. Solutions of HA can be highly viscous with non-Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and underlying the deep fascia. Changes in the concentration, molecular weight, or even covalent modification of HA in inflammatory conditions, as well as changes in binding interactions with other macromolecules, can have dramatic effects on the sliding movement of fascia. The high molecular weight and the semi-flexible chain of HA are key factors leading to the high viscosity of dilute solutions, and real HA solutions show additional nonideality and greatly increased viscosity due to mutual macromolecular crowding. The shear rate dependence of the viscosity, and the viscoelasticity of HA solutions, depend on the relaxation time of the molecule, which in turn depends on the HA concentration and molecular weight. Temperature can also have an effect on these properties. High viscosity can additionally affect the lubricating function of HA solutions. Immobility can increase the concentration of HA, increase the viscosity, and reduce lubrication and gliding of the layers of connective tissue and muscle. Over time, these changes can alter both muscle structure and function. Inflammation can further increase the viscosity of HA-containing fluids if the HA is modified via covalent attachment of heavy chains derived from Inter-α-Inhibitor. Hyaluronidase hydrolyzes HA, thus reducing its molecular weight, lowering the viscosity of the extracellular matrix fluid and making outflow easier. It can also disrupt any aggregates or gel-like structures that result from HA being modified. Hyaluronidase is used medically primarily as a dispersion agent, but may also be useful in conditions where altered viscosity of the fascia is desired, such as in the treatment of

  12. Regulated Hyaluronan Synthesis by Vascular Cells

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    Manuela Viola

    2015-01-01

    Full Text Available Cellular microenvironment plays a critical role in several pathologies including atherosclerosis. Hyaluronan (HA content often reflects the progression of this disease in promoting vessel thickening and cell migration. HA synthesis is regulated by several factors, including the phosphorylation of HA synthase 2 (HAS2 and other covalent modifications including ubiquitination and O-GlcNAcylation. Substrate availability is important in HA synthesis control. Specific drugs reducing the UDP precursors are able to reduce HA synthesis whereas the hexosamine biosynthetic pathway (HBP increases the concentration of HA precursor UDP-N-acetylglucosamine (UDP-GlcNAc leading to an increase of HA synthesis. The flux through the HBP in the regulation of HA biosynthesis in human aortic vascular smooth muscle cells (VSMCs was reported as a critical aspect. In fact, inhibiting O-GlcNAcylation reduced HA production whereas increased O-GlcNAcylation augmented HA secretion. Additionally, O-GlcNAcylation regulates HAS2 gene expression resulting in accumulation of its mRNA after induction of O-GlcNAcylation with glucosamine treatments. The oxidized LDLs, the most common molecules related to atherosclerosis outcome and progression, are also able to induce a strong HA synthesis when they are in contact with vascular cells. In this review, we present recent described mechanisms involved in HA synthesis regulation and their role in atherosclerosis outcome and development.

  13. Rheology of mixed alginate-hyaluronan aqueous solutions.

    Science.gov (United States)

    Travan, Andrea; Fiorentino, Simona; Grassi, Mario; Borgogna, Massimiliano; Marsich, Eleonora; Paoletti, Sergio; Donati, Ivan

    2015-01-01

    The present manuscript addresses the description of binary systems of hyaluronan (HA) and alginate (Alg) in semi-concentrated solution. The two polysaccharides were completely miscible in the entire range of relative weight fraction explored at a total polymer concentration of up to 3% (w/V). The rheological study encompassed steady flow and mechanical spectra for HA/Alg systems at different weight fractions with hyaluronan at different molecular weights. These extensive analyses allowed us to propose a model for the molecular arrangement in solution that envisages a mutual exclusion between the two polysaccharides even though a clear phase separation does not occur. This result may have profound implications when combinations of alginate and hyaluronan are proposed in the field of biomedical materials.

  14. Over expression of hyaluronan promotes progression of HCC via CD44-mediated pyruvate kinase M2 nuclear translocation

    Science.gov (United States)

    Li, Jing-Huan; Wang, Ying-Cong; Qin, Cheng-Dong; Yao, Rong-Rong; Zhang, Rui; Wang, Yan; Xie, Xiao-Ying; Zhang, Lan; Wang, Yan-Hong; Ren, Zheng-Gang

    2016-01-01

    Hyaluronan is expressed in hepatocellular carcinoma (HCC) as HCC generally arises from a cirrhotic liver in which excessive production and accumulation of HA leads to developing cirrhosis. Though it has been suggested HA is involved in progression of HCC, the mechanisms underlying the connection between HA and HCC progression are unclear. Since increased aerobic glycolysis is a metabolic trait of malignant cells and HA-CD44 can modulate glucose metabolism, we aim to investigate the roles of PKM2, a key enzyme in glucose metabolism, in the HA-CD44 axis facilitated the progress of HCC. We shown PKM2 was required for HA-promoted HCC progression, which was not modulated by PKM2 kinase activity but by nuclear translocation of PKM2. PKM2 translocation was Erk (Thr202/Tyr204) phosphorylation dependent, which functioned at the downstream of HA-CD44 binding. Furthermore, elevated HA expression significantly correlated with PKM2 nuclear location and was an independent factors predicting poor HCC prognosis. In conclusions PKM2 nuclear translocation is required for mediating the described HA biological effects on HCC progression and our results imply that inhibition of HA may have therapeutic value in treating HCC. PMID:27186420

  15. Increased Hyaluronan Levels in HABP1/p32/gC1qR Overexpressing HepG2 Cells Inhibit Autophagic Vacuolation Regulating Tumor Potency

    Science.gov (United States)

    Saha, Paramita; Ghosh, Ilora; Datta, Kasturi

    2014-01-01

    Tumor growth and development is influenced by its microenvironment. A major extracellular matrix molecule involved in cancer progression is hyaluronan (HA). Hyaluronan and expression of a number of hyaladherin family proteins are dramatically increased in many cancer malignancies. One such hyaladherin, hyaluronan-binding protein 1 (HABP1/p32/gC1qR) has been considered to be a biomarker for tumor progression. Interestingly, overexpression of HABP1 in fibroblast has been shown to increase autophagy via generation of excess reactive oxygen species (ROS) and depletion of HA leading to apoptosis. Cancerous cells are often found to exhibit decreased rate of proteolysis/autophagy in comparison to their normal counterparts. To determine if HABP1 levels alter tumorigenicity of cancerous cells, HepR21, the stable transfectant overexpressing HABP1 in HepG2 cell line was derived. HepR21 has been shown to have increased proliferation rate than HepG2, intracellular HA cable formation and enhanced tumor potency without any significant alteration of intracellular ROS. In this paper we have observed that HepR21 cells containing higher endogenous HA levels, have downregulated expression of the autophagic marker, MAP-LC3, consistent with unaltered levels of endogenous ROS. In fact, HepR21 cells seem to have significant resistance to exogenous ROS stimuli and glutathione depletion. HepR21 cells were also found to be more resilient to nutrient starvation in comparison to its parent cell line. Decline in intracellular HA levels and HA cables in HepR21 cells upon treatment with HAS inhibitor (4-MU), induced a surge in ROS levels leading to increased expression of MAP-LC3 and tumor suppressors Beclin 1 and PTEN. This suggests the importance of HABP1 induced HA cable formation in enhancing tumor potency by maintaining the oxidant levels and subsequent autophagic vacuolation. PMID:25061661

  16. Inhibition of hyaluronan synthesis reduces versican and fibronectin levels in trabecular meshwork cells.

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    Kate E Keller

    Full Text Available Hyaluronan (HA is a major component of the extracellular matrix (ECM and is synthesized by three HA synthases (HAS. Similarities between the HAS2 knockout mouse and the hdf mutant mouse, which has a mutation in the versican gene, suggest that HA and versican expression may be linked. In this study, the relationship between HA synthesis and levels of versican, fibronectin and several other ECM components in trabecular meshwork cells from the anterior segment of the eye was investigated. HA synthesis was inhibited using 4-methylumbelliferone (4MU, or reduced by RNAi silencing of each individual HAS gene. Quantitative RT-PCR and immunoblotting demonstrated a reduction in mRNA and protein levels of versican and fibronectin. Hyaluronidase treatment also reduced versican and fibronectin levels. These effects could not be reversed by addition of excess glucose or glucosamine or exogenous HA to the culture medium. CD44, tenascin C and fibrillin-1 mRNA levels were reduced by 4MU treatment, but SPARC and CSPG6 mRNA levels were unaffected. Immunostaining of trabecular meshwork tissue after exposure to 4MU showed an altered localization pattern of HA-binding protein, versican and fibronectin. Reduction of versican by RNAi silencing did not affect HA concentration as assessed by ELISA. Together, these data imply that HA concentration affects synthesis of certain ECM components. Since precise regulation of the trabecular meshwork ECM composition and organization is required to maintain the aqueous humor outflow resistance and intraocular pressure homeostasis in the eye, coordinated coupling of HA levels and several of its ECM binding partners should facilitate this process.

  17. Synthesis and characterization of collagen/hyaluronan/chitosan composite sponges for potential biomedical applications.

    Science.gov (United States)

    Lin, Yen-Chih; Tan, Fa-Jui; Marra, Kacey G; Jan, Shyh-Shyan; Liu, Deng-Cheng

    2009-09-01

    Cells, scaffolds and growth factors are three main components of a tissue-engineered construct. Collagen type I, a major protein of the extracellular matrix (ECM) in mammals, is a suitable scaffold material for regeneration. Another important constituent of the ECM, hyaluronic acid (hyaluronan, HA), has been used for medical purposes due to its hydrogel properties and biodegradability. Chitosan is a linear polysaccharide comprised of beta1- to beta4-linked d-glucosamine residues, and its potential as a biomaterial is based on its cationic nature and high charge density in solution. This study was conducted to evaluate the characteristics of scaffolds composed of different ratios of type I comb collagen and chitosan with added HA in order to obtain the optimum conditions for the manufacture of collagen-hyaluronan-chitosan (Col-HA-Ch; comprising collagen, HA and chitosan mixed in different ratios: 10:1:0, Col10HACh0; 9:1:1, Col9HACh1; 8:1:2, Col8HACh2; 7:1:3, Col7HACh3; 6:1:4, Col6HACh4; and 5:1:5, Col5HACh5) composite porous scaffolds. Microstructural observation of the composite scaffolds was performed using scanning electron microscopy. The mean pore diameters ranged from 120 to 182microm and decreased as the chitosan composition increased. All scaffolds showed high pore interconnectivity. Swelling ratio measurements showed that all specimens could bind 35- to 40-fold of physiological fluid and still maintain their form and stability. For tensile strength, the optimal ratio of collagen and chitosan was 9:1. Thermal stability was investigated using a differential scanning calorimeter and showed that Col5HACh5 and Col6HACh4 were significantly more stable than the other groups. In enzymatic sensitivity, a steady increase in the biostability of the scaffolds was achieved as the chitosan concentration was increased. In biocompatibility testing, the proliferation of the fibroblasts cultured in Co-HA-Ch tri-copolymer scaffolds was high. Overall, we observed the 9

  18. Genetic Association and Gene-gene interaction of HAS2, HABP1 and HYAL3 Implicate Hyaluronan Metabolic Genes in Glaucomatous Neurodegeneration

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    Kaustuv Basu

    2012-01-01

    Full Text Available Hyaluronan (HA plays a significant role in maintaining aqueous humor outflow in trabecular meshwork, the primary ocular tissue involved in glaucoma. We examined potential association of the single nucleotide polymorphisms (SNPs of the HA synthesizing gene – hyaluronan synthase 2 (HAS2, hyaluronan binding protein 1 (HABP1 and HA catabolic gene hyaluronidase 3 (HYAL3 in the primary open angle glaucoma (POAG patients in the Indian population. Thirteen tagged SNPs (6 for HAS2, 3 for HABP1 and 4 for HYAL3 were genotyped in 116 high tension (HTG, 321 non-high tension glaucoma (NHTG samples and 96 unrelated, age-matched, glaucoma-negative, control samples. Allelic and genotypic association were analyzed by PLINK v1.04; haplotypes were identified using PHASE v2.1 and gene-gene interaction was analyzed using multifactor dimensionality reduction (MDR v2.0. An allelic association (rs6651224; p = 0.03; OR: 0.49; 95% CI: 0.25–0.94 was observed at the second intron (C>G of HAS2 both for NHTG and HTG. rs1057308 revealed a genotypic association (p = 0.03 at the 5’ UTR of HAS2 with only HTG. TCT haplotype (rs1805429 – rs2472614 – rs8072363 in HABP1 and TTAG and TTGA (rs2285044 – rs3774753 – rs1310073 – rs1076872 in HYAL3 were found to be significantly high (p < 0.05 both for HTG and NHTG compared to controls. Gene-gene interaction revealed HABP1 predominantly interacts with HAS2 in HTG while it associates with both HYAL3 and HAS2 in NHTG. This is the first genetic evidence, albeit from a smaller study, that the natural polymorphisms in the genes involved in hyaluronan metabolism are potentially involved in glaucomatous neurodegeneration.

  19. Agarose and Polyacrylamide Gel Electrophoresis Methods for Molecular Mass Analysis of 5–500 kDa Hyaluronan

    Science.gov (United States)

    Bhilocha, Shardul; Amin, Ripal; Pandya, Monika; Yuan, Han; Tank, Mihir; LoBello, Jaclyn; Shytuhina, Anastasia; Wang, Wenlan; Wisniewski, Hans-Georg; de la Motte, Carol; Cowman, Mary K.

    2011-01-01

    Agarose and polyacrylamide gel electrophoresis systems for the molecular mass-dependent separation of hyaluronan (HA) in the size range of approximately 5–500 kDa have been investigated. For agarose-based systems, the suitability of different agarose types, agarose concentrations, and buffers systems were determined. Using chemoenzymatically synthesized HA standards of low polydispersity, the molecular mass range was determined for each gel composition, over which the relationship between HA mobility and logarithm of the molecular mass was linear. Excellent linear calibration was obtained for HA molecular mass as low as approximately 9 kDa in agarose gels. For higher resolution separation, and for extension to molecular masses as low as approximately 5 kDa, gradient polyacrylamide gels were superior. Densitometric scanning of stained gels allowed analysis of the range of molecular masses present in a sample, and calculation of weight-average and number-average values. The methods were validated for polydisperse HA samples with viscosity-average molecular masses of 112, 59, 37, and 22 kDa, at sample loads of 0.5 µg (for polyacrylamide) to 2.5 µg (for agarose). Use of the methods for electrophoretic mobility shift assays was demonstrated for binding of the HA-binding region of aggrecan (recombinant human aggrecan G1-IGD-G2 domains) to a 150 kDa HA standard. PMID:21684248

  20. Hyaluronan synthase 3 mediated oncogenic action through forming inter-regulation loop with tumor necrosis factor alpha in oral cancer

    Science.gov (United States)

    Kuo, Yi-Zih; Fang, Wei-Yu; Huang, Cheng-Chih; Tsai, Sen-Tien; Wang, Yi-Ching; Yang, Chih-Li; Wu, Li-Wha

    2017-01-01

    Hyaluronan (HA) is a major extracellular matrix component. However, its role and mediation in oral cancer remains elusive. Hyaluronan synthase 3 (HAS3), involved in pro-inflammatory short chain HA synthesis, was the predominant synthase in oral cancer cells and tissues. HAS3 overexpression significantly increased oral cancer cell migration, invasion and xenograft tumorigenesis accompanied with the increased expression of tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein 1 (MCP-1). Conversely, HAS3 depletion abrogated HAS3-mediated stimulation. HAS3 induced oncogenic actions partly through activating EGFR-SRC signaling. HAS3-derived HA release into extracellular milieu enhanced transendothelial monocyte migration and MCP-1 expression, which was attenuated by anti-HAS3 antibodies or a HAS inhibitor, 4-Methylumbelliferone (4-MU). The NF-κB-binding site III at -1692 to -1682 bp upstream from the transcript 1 start site in HAS3 proximal promoter was the most responsive to TNF-α-stimulated transcription. ChIP-qPCR analysis confirmed the highest NF-κB-p65 enrichment on site III. Increased HAS3 mRNA expression was negatively correlated with the overall survival of oral cancer patients. A concomitant increase of TNF-α, a stimulus for HAS3 expression, with HAS3 expression was not only associated with lymph node metastasis but also negated clinical outcome. Together, HAS3 and TNF-α formed an inter-regulation loop to enhance tumorigenesis in oral cancer. PMID:28107185

  1. Novel enzymatically cross-linked hyaluronan hydrogels support the formation of 3D neuronal networks.

    Science.gov (United States)

    Broguiere, Nicolas; Isenmann, Luca; Zenobi-Wong, Marcy

    2016-08-01

    Hyaluronan (HA) is an essential component of the central nervous system's extracellular matrix and its high molecular weight (MW) form has anti-inflammatory and anti-fibrotic properties relevant for regenerative medicine. Here, we introduce a new hydrogel based on high MW HA which is cross-linked using the transglutaminase (TG) activity of the activated blood coagulation factor XIII (FXIIIa). These HA-TG gels have significant advantages for neural tissue engineering compared to previous HA gels. Due to their chemical inertness in the absence of FXIIIa, the material can be stored long-term, is stable in solution, and shows no cytotoxicity. The gelation is completely cell-friendly due to the specificity of the enzyme and the gelation rate can be tuned from seconds to hours at physiological pH and independently of stiffness. The gels are injectable, and attach covalently to fibrinogen and fibrin, two common bioactive components in in vitro tissue engineering, as well as proteins present in vivo, allowing the gels to covalently bind to brain or spinal cord defects. These optimal chemical and bioactive properties of HA-TG gels enabled the formation of 3D neuronal cultures of unprecedented performance, showing fast neurite outgrowth, axonal and dendritic speciation, strong synaptic connectivity in 3D networks, and rapidly-occurring and long-lasting coordinated electrical activity.

  2. Hyaluronan: A modulator of the tumor microenvironment.

    Science.gov (United States)

    Chanmee, Theerawut; Ontong, Pawared; Itano, Naoki

    2016-05-28

    Tumors are cellular masses formed through dynamic interactions between tumor cells and a mixed population of stromal cells. Crosstalk between oncogenic and adjacent stromal cells contributes to the formation of a "tumor microenvironment" influencing the tumor cell behaviors of proliferation, invasion, and metastatic spread throughout cancer progression. The composition and structure of the tumor microenvironment vary among different types of tumors and are extensively remodeled in close association with tumor advancement. The tumor microenvironment is composed not only of cellular compartments, such as endothelial cells, fibroblasts, inflammatory cells, and immune cells, but also of bioactive substances, including growth factors and the extracellular matrix. Hyaluronan (HA) is a major component of the extracellular matrix, and the degree of HA accumulation is strongly correlated with a poor prognosis in advanced cancer patients. Emerging evidence has suggested that HA creates a specific microenvironment that is favorable for tumor angiogenesis, invasion, and metastasis. This review highlights the prominent roles of HA as a modulator of the tumor microenvironment and addresses the recent advances regarding HA function in cancer stem cell niches. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Hyaluronan Tumor Cell Interactions in Prostate Cancer Growth and Survival

    Science.gov (United States)

    2008-12-01

    RHAMM remaining following CD44 knockdown. Secondly, RHAMM will be knocked down using RNAi and the level of CD44 remaining will be measured using Western...hyaluronidase pretreatment or by using RNAi for the hyaluronan synthase enzymes expressed by these cells. The prediction, again, is that limiting HA...vertebrates and is not found in lower organisms or in insects (Fig. 9.2). Given its roles in such important cellular processes as motility and cell division in

  4. Priming Adipose-Derived Mesenchymal Stem Cells with Hyaluronan Alters Growth Kinetics and Increases Attachment to Articular Cartilage

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    Peter Succar

    2016-01-01

    Full Text Available Background. Biological therapeutics such as adipose-derived mesenchymal stem cell (MSC therapy are gaining acceptance for knee-osteoarthritis (OA treatment. Reports of OA-patients show reductions in cartilage defects and regeneration of hyaline-like-cartilage with MSC-therapy. Suspending MSCs in hyaluronan commonly occurs in animals and humans, usually without supporting data. Objective. To elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics. Methods. Using a range of hyaluronan concentrations, we measured MSC adherence and proliferation on culture plastic surfaces and a novel cartilage-adhesion assay. We employed time-course and dispersion imaging to assess MSC binding to cartilage. Cytokine profiling was also conducted on the MSC-secretome. Results. Hyaluronan had dose-dependent effects on growth kinetics of MSCs at concentrations of entanglement point (1 mg/mL. At higher concentrations, viscosity effects outweighed benefits of additional hyaluronan. The cartilage-adhesion assay highlighted for the first time that hyaluronan-primed MSCs increased cell attachment to cartilage whilst the presence of hyaluronan did not. Our time-course suggested patients undergoing MSC-therapy for OA could benefit from joint-immobilisation for up to 8 hours. Hyaluronan also greatly affected dispersion of MSCs on cartilage. Conclusion. Our results should be considered in future trials with MSC-therapy using hyaluronan as a vehicle, for the treatment of OA.

  5. The Content and Size of Hyaluronan in Biological Fluids and Tissues

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    Mary K. Cowman

    2015-06-01

    Full Text Available Hyaluronan is a simple repeating disaccharide polymer, synthesized at the cell surface by integral membrane synthases. The repeating sequence is perfectly homogeneous, and is the same in all vertebrate tissues and fluids. The polymer molecular mass is more variable. Most commonly, hyaluronan is synthesized as a high molecular mass polymer, with an average molecular mass of approximately 1000-8000 kDa. There are a number of studies showing increased hyaluronan content, but reduced average molecular mass with a broader range of sizes present, in tissues or fluids when inflammatory or tissue remodeling processes occur. In parallel studies, exogenous hyaluronan fragments of low molecular mass (generally, less than about 200 kDa have been shown to affect cell behavior through binding to receptor proteins such as CD44 and RHAMM (gene name HMMR, and to signal either directly or indirectly through Toll-like receptors. These data suggest that receptor sensitivity to hyaluronan size provides a biosensor of the state of the microenvironment surrounding the cell. Sensitive methods for isolation and characterization of hyaluronan and its fragments have been developed and continue to improve. This review provides an overview of the methods and our current state of knowledge of hyaluronan content and size distribution in biological fluids and tissues.

  6. Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

    Science.gov (United States)

    Hill, David R.; Rho, Hyunjin K.; Kessler, Sean P.; Amin, Ripal; Homer, Craig R.; McDonald, Christine; Cowman, Mary K.; de la Motte, Carol A.

    2013-01-01

    Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

  7. Human milk hyaluronan enhances innate defense of the intestinal epithelium.

    Science.gov (United States)

    Hill, David R; Rho, Hyunjin K; Kessler, Sean P; Amin, Ripal; Homer, Craig R; McDonald, Christine; Cowman, Mary K; de la Motte, Carol A

    2013-10-04

    Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn.

  8. Regulation of Synthesis and Roles of Hyaluronan in Peritoneal Dialysis

    Directory of Open Access Journals (Sweden)

    Timothy Bowen

    2015-01-01

    Full Text Available Hyaluronan (HA is a ubiquitous extracellular matrix glycosaminoglycan composed of repeated disaccharide units of alternating D-glucuronic acid and D-N-acetylglucosamine residues linked via alternating β-1,4 and β-1,3 glycosidic bonds. HA is synthesized in humans by HA synthase (HAS enzymes 1, 2, and 3, which are encoded by the corresponding HAS genes. Previous in vitro studies have shown characteristic changes in HAS expression and increased HA synthesis in response to wounding and proinflammatory cytokines in human peritoneal mesothelial cells. In addition, in vivo models and human peritoneal biopsy samples have provided evidence of changes in HA metabolism in the fibrosis that at present accompanies peritoneal dialysis treatment. This review discusses these published observations and how they might contribute to improvement in peritoneal dialysis.

  9. Evaluation of emulsion electrospun polycaprolactone/hyaluronan/epidermal growth factor nanofibrous scaffolds for wound healing.

    Science.gov (United States)

    Wang, Zhenbei; Qian, Yuna; Li, Linhao; Pan, Lianhong; Njunge, Lucy W; Dong, Lili; Yang, Li

    2016-01-01

    Wound healing scaffolds provide cells with structural integrity and can also deliver biological agents to establish a skin tissue-specific microenvironment to regulate cell functions and to accelerate the healing process. In this study, we fabricated biodegradable nanofibrous scaffolds with an emulsion electrospinning technique. The scaffolds were composed of polycaprolactone, hyaluronan and encapsulating epidermal growth factor. The morphology and core-sheath structure of the nanofibers were characterized by scanning electron microscopy and transmission electron microscopy. The scaffolds were also characterized for chemical composition and hydrophilicity with a Fourier-transform infrared analysis, energy dispersive spectroscopy and the water contact angle. An in vitro model protein bovine serum albumin and epidermal growth factor release study was conducted to evaluate the sustained release potential of the core-sheath structured nanofibers with and without the hyaluronan component. Additionally, an in vitro cultivation of human skin keratinocytes (HaCaT) and fibroblasts on polycaprolactone/hyaluronan and polycaprolactone/hyaluronan-epidermal growth factor scaffolds showed a significant synergistic effect of hyaluronan and epidermal growth factor on cell proliferation and infiltration. Furthermore, there was an up-regulation of the wound-healing-related genes collagen I, collagen III and TGF-β in polycaprolactone/hyaluronan/epidermal growth factor scaffolds compared with control groups. In the full-thickness wound model, the enhanced regeneration of fully functional skin was facilitated by epidermal regeneration in the polycaprolactone/hyaluronan/epidermal growth factor treatment group. Our findings suggest that bioactivity and hemostasis of the hyaluronan-based nanofibrous scaffolds have the capability to encapsulate and control the release of growth factors that can serve as skin tissue engineering scaffolds for wound healing.

  10. Hyaluronan tetrasaccharides stimulate ceramide production through upregulated mRNA expression of ceramide synthesis-associated enzymes.

    Science.gov (United States)

    Kage, Madoka; Tokudome, Yoshihiro

    2016-03-01

    It has been reported that hyaluronan has different physiological functions as suggested by variation in molecular weight. In addition, it has also been reported that CD44, the major hyaluronan receptor, was demonstrated to induce keratinocyte differentiation and lipid synthesis of cholesterol. We focus attention on the hyaluronan tetrasaccharides (HA4) which is the smallest unit of hyaluronan. We previously reported that HA4 induced keratinocyte differentiation and that CD44 may be involved. For the purpose of clarifying the influence of HA4 on ceramide synthesis, we evaluated both of these factors in keratinocytes in vitro and in vivo. The mRNA expression of ceramide synthesis-associated enzymes and intracellular ceramide content were evaluated after HA4 treatment in normal human epidermal keratinocytes. In addition, the ceramide increasing effect of HA4 on skin in UVA-irradiated hairless mice was assessed by water content of stratum corneum (SC) and transepidermal water loss (TEWL) methods. The mRNA expression of ceramide synthesis-associated enzymes and intracellular ceramide content after HA4 treatment were increased compared with the control. Furthermore, HA4 treatment increased water content of SC and decreased TEWL. These findings suggest that HA4 affected ceramide synthesis and is involved in the improvement of UV-induced skin damage.

  11. Hyaluronan protects against cartilage damage by decreasing stiffness and changing3-D microarchitecture of subchondral bone in guinea pig primary osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, Ming

    Introduction: Hyaluronan (HA) is a biologic material, and a major component of synovial fluid. HA has received increasing interest as a potential agent of therapeutic intervention in osteoarthrosis (OA). High molecular weight HA has been shown to reduce arthritic lesions in experimental animal...

  12. Study on Preparation and Release of Dexamethasone Hyaluronan Microspheres

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hyaluronan (HA), the consistent glycosaminoglycans in extracellular matrix, is a kind of biomaterials with wonderful biocompatibility. To develop drug release system (DDS) with HA as drug carrier is a new hotspot in the field of pharmaceutics. In this paper, we applied technique of ultrosound and reversed phase (Water/Oil) emulsification to develop dexamethasone (DEX)-HA-STMP cross-linking microspheres (DEX-HA MS) with STMP as cross-linker. DEX-HA MS has a wonderful shape and property of dispersion. There is a negative correlation between diameter of DEX-HA MS and the content of cross-linker, or the content of emulsifier, and a positive correlation between the diameter and CHA. When CHA≤1% ,DEX/HA≤1/10(g/g),there is a positive correlation between the factors mentioned below and drug loading (DL%)/loading efficiency (LE%) ,the content of STMP, the content of emulsifier, CHA and the content of DEX. DEX-HA-MS can realize function of slow release. In vitro drug release experiment shows that cumulative release (CR%) of DEX-HA MS fits in with pervasion-corrosion equation, and there is a negative correlation between the content of STMP, CHA and CR% , a positive correlation between emulsifier and CR%. When DEX/HA ≤1/5 (g/g) there is a negative correlation between the content of DEX and CR%.

  13. Cytokines and Growth Factors Stimulate Hyaluronan Production: Role of Hyaluronan in Epithelial to Mesenchymal-Like Transition in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Geraldine Chow

    2010-01-01

    Full Text Available In this study, we investigated the role of hyaluronan (HA in non-small cell lung cancer (NSCLC since close association between HA level and malignancy has been reported. HA is an abundant extracellular matrix component and its synthesis is regulated by growth factors and cytokines that include epidermal growth factor (EGF and interleukin-1β (IL-1β. We showed that treatment with recombinant EGF and IL-1β, alone or in combination with TGF-β, was able to stimulate HA production in lung adenocarcinoma cell line A549. TGF-β/IL-1β treatment induced epithelial to mesenchymal-like phenotype transition (EMT, changing cell morphology and expression of vimentin and E-cadherin. We also overexpressed hyaluronan synthase-3 (HAS3 in epithelial lung adenocarcinoma cell line H358, resulting in induced HA expression, EMT phenotype, enhanced MMP9 and MMP2 activities and increased invasion. Furthermore, adding exogenous HA to A549 cells and inducing HA H358 cells resulted in increased resistance to epidermal growth factor receptor (EGFR inhibitor, Iressa. Together, these results suggest that elevated HA production is able to induce EMT and increase resistance to Iressa in NSCLC. Therefore, regulation of HA level in NSCLC may be a new target for therapeutic intervention.

  14. Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Ningbo, E-mail: curl-zhao@163.com; Wang, Xin, E-mail: 394041230@qq.com; Qin, Lei, E-mail: qinlei30@126.com; Guo, Zhengze, E-mail: zhzeguo@163.com; Li, Dehua, E-mail: lidehuafmmu@163.com

    2015-09-25

    Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect.

  15. Rheological properties of aqueous solutions of biopolymeric hyaluronan

    Science.gov (United States)

    Szwajczak, Elzbieta

    2004-09-01

    Aqueous solutions of hyaluronic acid (hyaluronan, HA) were studied. The HA compound is a natural polysaccharide, bipolymer. It plays an important role in numerous biological processes as a component of the extracellular matrix, connective tissues and, especially, human and animal synovial joints. Natural and artificial solutions of the HA have demonstrated the viscoelastic nature. These properties are shown to be related to the microstructure parameters (bulk concentration, molecular weight) and external parameters (temperature, stress, shear rate). We emphasize the role of the flow properties of polymeric systems. It is found a liquid crystalline "order" can be "induced" during the material flow. The dynamic properties, such as the elastic shear modulus and viscous shear modulus, are given. These results are discussed in relation to the postulated function of hyaluronic acid in synovial joint and with respect to possibilities o their application in medicine and pharmacology.

  16. NMR study of hydroxy and amide protons in hyaluronan polymers.

    Science.gov (United States)

    Nestor, Gustav; Sandström, Corine

    2017-02-10

    Hyaluronan (HA) is an important and well characterized glycosaminoglycan with high viscosity and water-retaining capacity. Nonetheless, it is not fully understood whether conformational properties of the easily characterized HA oligomers can be transferred to HA polymers. To investigate possible differences in hydration, hydrogen bonding and flexibility between HA polymers and oligomers, hydroxy and amide protons of HA polymers were studied by solution-state and high-resolution magic angle spinning (HR-MAS) NMR spectroscopy. Measurements of chemical shifts, temperature coefficients and NOEs in HA polymers revealed that the NMR data are very similar compared to the interior of a HA octasaccharide, supporting transient hydrogen bond interactions across the β(1→3) and β(1→4) glycosidic linkages. However, differences in NOEs suggested a cis-like orientation between NH and H2 in the HA polymer. The lack of concentration dependence of the hydroxy proton chemical shifts suggests that there are no direct inter-chain interactions involving hydroxy protons at the concentrations investigated.

  17. On the demixing of hyaluronan and alginate in the gel state.

    Science.gov (United States)

    Scognamiglio, Francesca; Travan, Andrea; Cok, Michela; Borgogna, Massimiliano; Marsich, Eleonora; Paoletti, Sergio; Donati, Ivan

    2017-02-01

    The manuscript focuses on the demixing of hyaluronan and alginate in the hydrogel state. Binary solutions of the two polysaccharides have been treated with Ca(2+) as the alginate cross-linking ion and the radial distribution of the two components in the hydrogels was measured by means of (1)H NMR. These results revealed the presence of alginate-enriched and hyaluronan-enriched domains stemming from a polysaccharide demixing. The hydrogels were characterized by means of uniaxial compression and creep-compliance measurements which showed that the demixing increased the overall resistance of the hydrogel to stress. In addition, due to the viscoelastic properties of hyaluronan, a marked increase of the Newtonian viscosity of the constructs was noticed. The peculiarity of the effect of hyaluronan was demonstrated by the use of an alginate unable to form gel by binding non-calcium binding alginate, i.e. mannuronan, ruling out the effect of viscosity over the time-dependent behavior of the mixed hyaluronan-alginate hydrogels. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Group B Streptococcus Evades Host Immunity by Degrading Hyaluronan.

    Science.gov (United States)

    Kolar, Stacey L; Kyme, Pierre; Tseng, Ching Wen; Soliman, Antoine; Kaplan, Amber; Liang, Jiurong; Nizet, Victor; Jiang, Dianhua; Murali, Ramachandran; Arditi, Moshe; Underhill, David M; Liu, George Y

    2015-12-09

    In response to tissue injury, hyaluronan (HA) polymers are cleaved by host hyaluronidases, generating small fragments that ligate Toll-like receptors (TLRs) to elicit inflammatory responses. Pathogenic bacteria such as group B Streptococcus (GBS) express and secrete hyaluronidases as a mechanism for tissue invasion, but it is not known how this activity relates to immune detection of HA. We found that bacterial hyaluronidases secreted by GBS and other Gram-positive pathogens degrade pro-inflammatory HA fragments to their component disaccharides. In addition, HA disaccharides block TLR2/4 signaling elicited by both host-derived HA fragments and other TLR2/4 ligands, including lipopolysaccharide. Application of GBS hyaluronidase or HA disaccharides reduced pulmonary pathology and pro-inflammatory cytokine levels in an acute lung injury model. We conclude that breakdown of host-generated pro-inflammatory HA fragments to disaccharides allows bacterial pathogens to evade immune detection and could be exploited as a strategy to treat inflammatory diseases.

  19. Characterization of three novel fatty acid- and retinoid-binding protein genes (Ha-far-1, Ha-far-2 and Hf-far-1) from the cereal cyst nematodes Heterodera avenae and H. filipjevi

    Science.gov (United States)

    Heterodera avenae and H. filipjevi are major parasites of wheat, reducing production worldwide. Both are sedentary endoparasitic nematodes, and their development and parasitism depend strongly on nutrients obtained from hosts. Secreted fatty acid- and retinoid-binding (FAR) proteins are nematode-spe...

  20. Crucial role of hyaluronan in neointimal formation after vascular injury.

    Directory of Open Access Journals (Sweden)

    Yuichiro Kashima

    Full Text Available BACKGROUND: Hyaluronan (HA is a primary component of the extracellular matrix of cells, and it is involved in the pathogenesis of atherosclerosis. The purpose of this study was to investigate the role of HA in neointimal formation after vascular injury and determine its tissue-specific role in vascular smooth muscle cells (VSMCs by using a cre-lox conditional transgenic (cTg strategy. METHODS AND RESULTS: HA was found to be expressed in neointimal lesions in humans with atherosclerosis and after wire-mediated vascular injury in mice. Inhibition of HA synthesis using 4-methylumbelliferone markedly inhibited neointimal formation after injury. In vitro experiments revealed that low-molecular-weight HA (LMW-HA induced VSMC activation, including migration, proliferation, and production of inflammatory cytokines, and reactive oxygen species (ROS. The migration and proliferation of VSMCs were mediated by the CD44/RhoA and CD44/ERK1/2 pathways, respectively. Because HA synthase 2 (HAS2 is predominantly expressed in injured arteries, we generated cTg mice that overexpress the murine HAS2 gene specifically in VSMCs (cHAS2/CreSM22α mice and showed that HA overexpression markedly enhanced neointimal formation after cuff-mediated vascular injury. Further, HA-overexpressing VSMCs isolated from cHAS2/CreSM22α mice showed augmented migration, proliferation, and production of inflammatory cytokines and ROS. CONCLUSION: VSMC-derived HA promotes neointimal formation after vascular injury, and HA may be a potential therapeutic target for cardiovascular disease.

  1. Hyaluronan in human deciduous tooth germs in the bell stage. Histochemistry and immunohistochemistry

    DEFF Research Database (Denmark)

    Matthiessen, Martin Ebbe; Garbarsch, Charly; Olsen, Birgitte Engelbrecht

    1997-01-01

    Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry......Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry...

  2. A novel photopolymerizable derivative of hyaluronan for designed hydrogel formation.

    Science.gov (United States)

    Bobula, Tomáš; Buffa, Radovan; Hermannová, Martina; Kohutová, Lenka; Procházková, Pavlína; Vágnerová, Hana; Čepa, Martin; Wolfová, Lucie; Židek, Ondřej; Velebný, Vladimír

    2017-04-01

    A new photopolymerizable derivative of hyaluronan (methacrylhydrazide-HA, MAHA) was prepared by carbodiimide chemistry. The reaction conditions were optimized for molecular weight (Mw), reaction time and amount of reagents with a degree of methacrylation (DM) ranging from 2% to 58%. Methacrylhydrazide-HA was hydrolytically stable (PBS, 7days, 37°C) in contrast to commonly used methacrylester analoque (23% hydrolyzed). MAHA readily photopolymerized into densely crosslinked hydrogels under physiological conditions. The varied DM, Mw, irradiation time (texp) and macromer concentration in photocrosslinking afforded hydrogels with different physical (swelling ratio, degradation rate) and mechanical properties (stiffness, toughness). Three-dimensional fabrication and surface patterning of MAHA hydrogels were demonstrated by photolithography and light mediated micromolding. A live-dead assay with skin fibroblasts showed convenient biocompatibility of MAHA (16%, 116kDa) for potential scaffolding applications in tissue engineering and regenerative medicine.

  3. CD147: regulator of hyaluronan signaling in invasiveness and chemoresistance.

    Science.gov (United States)

    Grass, G Daniel; Dai, Lu; Qin, Zhiqiang; Parsons, Chris; Toole, Bryan P

    2014-01-01

    Major determinants that influence negative outcome in cancer patients are the abilities of cancer cells to resist current therapies and to invade surrounding host tissue, consequently leading to local and metastatic dissemination. Hyaluronan (HA), a prominent constituent of the tumor microenvironment, not only provides structural support but also interacts with cell surface receptors, especially CD44, that influence cooperative signaling pathways leading to chemoresistance and invasiveness. CD147 (emmprin; basigin) is a member of the Ig superfamily that has also been strongly implicated in chemoresistance and invasiveness. CD147 both regulates HA synthesis and interacts with the HA receptors, CD44, and LYVE-1. Increased CD147 expression induces formation of multiprotein complexes containing CD44 (or LYVE-1) as well as members of the membrane-type matrix metalloproteinase, receptor tyrosine kinase, ABC drug transporter, or monocarboxylate transporter families, which become assembled in specialized lipid raft domains along with CD147 itself. In each case, multivalent HA-receptor interactions are essential for formation or stabilization of the lipid raft complexes and for downstream signaling pathways or transporter activities that are driven by these complexes. We conclude that cooperativity between HA, HA receptors, and CD147 may be a major driver of the interconnected pathways of invasiveness and chemoresistance widely critical to malignancy.

  4. Alginate-hyaluronan composite hydrogels accelerate wound healing process.

    Science.gov (United States)

    Catanzano, O; D'Esposito, V; Acierno, S; Ambrosio, M R; De Caro, C; Avagliano, C; Russo, P; Russo, R; Miro, A; Ungaro, F; Calignano, A; Formisano, P; Quaglia, F

    2015-10-20

    In this paper we propose polysaccharide hydrogels combining alginate (ALG) and hyaluronan (HA) as biofunctional platform for dermal wound repair. Hydrogels produced by internal gelation were homogeneous and easy to handle. Rheological evaluation of gelation kinetics of ALG/HA mixtures at different ratios allowed understanding the HA effect on ALG cross-linking process. Disk-shaped hydrogels, at different ALG/HA ratio, were characterized for morphology, homogeneity and mechanical properties. Results suggest that, although the presence of HA does significantly slow down gelation kinetics, the concentration of cross-links reached at the end of gelation is scarcely affected. The in vitro activity of ALG/HA dressings was tested on adipose derived multipotent adult stem cells (Ad-MSC) and an immortalized keratinocyte cell line (HaCaT). Hydrogels did not interfere with cell viability in both cells lines, but significantly promoted gap closure in a scratch assay at early (1 day) and late (5 days) stages as compared to hydrogels made of ALG alone (p<0.01 and 0.001 for Ad-MSC and HaCaT, respectively). In vivo wound healing studies, conducted on a rat model of excised wound indicated that after 5 days ALG/HA hydrogels significantly promoted wound closure as compared to ALG ones (p<0.001). Overall results demonstrate that the integration of HA in a physically cross-linked ALG hydrogel can be a versatile strategy to promote wound healing that can be easily translated in a clinical setting.

  5. Hyaluronan synthase mediates dye translocation across liposomal membranes

    Directory of Open Access Journals (Sweden)

    Medina Andria P

    2012-01-01

    Full Text Available Abstract Background Hyaluronan (HA is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS, which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS to liposomes preloaded with the fluorophore Cascade Blue (CB. Results CB translocation (efflux was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL. An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL and that, in contrast, tetramyristoyl cardiolipin (TM-CL is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006. Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL. Conclusions The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself.

  6. Effect of hyaluronan on osteogenic differentiation of porcine bone marrow stromal cells in vitro

    DEFF Research Database (Denmark)

    Zou, Lijin; Zou, Xuenong; Chen, Li

    2007-01-01

    Hyaluronan (HA) plays a predominant role in tissue morphogenesis, cell migration, proliferation, and cell differentiation. The aims of the present study were to investigate whether (i) prolonged presence of high concentration (4.0 mg/mL) 800 KDa HA and (ii) pretreatment with HA can modify...... osteogenic differentiation of pig bone marrow stromal cells (pBMSC). Cell proliferation and mineralization were measured. Expression of differentiation-related genes was evaluated by means of real-time reverse transcription polymerase chain reaction (RT-PCR). HA increased cell proliferation on day 7. HA...... decreased the basal level of bone-related gene expression and increased the basal level of sox9 marginally during 7-day pretreatment with HA. HA increased calcium deposit on day 21. cbfa1, ALP, and type 1alpha collagen (Col1) expression was increased when pBMSC were cultivated in osteogenic medium, whereas...

  7. Growth promoting effect of hyaluronan synthesis promoting substances on Japanese eel leptocephali.

    Directory of Open Access Journals (Sweden)

    Yutaka Kawakami

    Full Text Available Hyaluronans (HAs are glycosaminoglycans produced in the bodies of Anguilliform and Elopiform leptocephali, and play a role in metabolic energy. In mammals, HA synthesis-promoting substances (HASPS up-regulate the expression of HA synthase (HAS and increase the amount of HA in the body. In this study, Japanese eel leptocephali were fed a HASPS containing diet. We analyzed HAS1s and HAS2 expression, HA content, and their influence on growth. HASPS extracted from Grifola frondosa promoted HAS1s and HAS2 mRNA and HA content. Other than mammals, these results are first reported in vertebrate. Moreover, HASPS extracted from G. frondosa promoted leptocephalus growth. The relationship between growth and HA in the leptocephali is not yet clear. However, based on our results we hypothesize that HA is involved in the storage of energy, which is metabolized to sugars when needed for metabolic energy.

  8. Lentiviral-mediated over-expression of hyaluronan synthase-1 (HAS-1) decreases the cellular inflammatory response and results in regenerative wound repair

    NARCIS (Netherlands)

    Caskey, Robert C.; Allukian, Myron; Lind, Robert C.; Herdrich, Benjamin J.; Xu, Junwang; Radu, Antoneta; Mitchell, Marc E.; Liechty, Kenneth W.

    2013-01-01

    Fetal wounds have been found to have increased levels of high-molecular-weight hyaluronan (HMW-HA) compared with those of adults. The primary enzyme responsible for producing HMW-HA is hyaluronic acid synthase-1 (HAS-1). We hypothesized that over-expression of HAS-1 in adult dermal wounds would decr

  9. Regulation of Non-Infectious Lung Injury, Inflammation, and Repair by the Extracellular Matrix Glycosaminoglycan Hyaluronan

    OpenAIRE

    Jiang, Dianhua; Liang, Jiurong; Noble, Paul W

    2010-01-01

    An important hallmark of tissue remodeling is the dynamic turnover of extracellular matrix (ECM). ECM performs a variety of functions in tissue repair including scaffold formation, modulation of fluid dynamics, and regulating cell behavior. During non-infectious tissue injury ECM degradation products are generated that acquire signaling functions not attributable to the native precursor molecules. Hyaluronan (HA) is a non-sulfated glycosaminoglycan which is produced in great abundance followi...

  10. Self-reinforcement and protein sustained delivery of hyaluronan hydrogel by tailoring a dually cross-linked network

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chunhong; Xu, Guoguang; Wang, Xinghui [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Tu, Mei; Zeng, Rong; Rong, Jianhua [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Zhao, Jianhao, E-mail: jhzhao@jnu.edu.cn [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

    2015-01-01

    A series of self-reinforcing hyaluronan hydrogels were developed to improve mechanical properties and protein sustained delivery thanks to a dually cross-linked network. Hyaluronan gel particles (HGPs, 1–5 μm in diameter) with different cross-linking densities, i.e. HGPs-1.5, HGPs-3 and HGPs-15, were prepared in an inverse emulsion system and used as the reinforcing phase after glycidyl methacrylation, while glycidyl methacrylated hyaluronan with a substitution degree of 45.2% was synthesized as the matrix phase. These two phases were cross-linked under ultraviolet irradiation to form self-reinforcing hyaluronan hydrogels (srHAs) that showed typical cross-linked structure of HGPs connecting the matrix phase by cross-section observation. In comparison to hyaluronan bulk gels and their blends with HGPs, srHAs distinctly enhanced the mechanical properties and BSA long-term sustained delivery, especially srHA-1.5 showed the highest compressive modulus of 220 ± 15 kPa and the slowest BSA delivery (67% release at 14 d). The 3T3 fibroblast cell culture showed that all the srHAs had no cytotoxicity. - Highlights: • New self-reinforcing HA hydrogels with a dually cross-linked network were developed. • Self-reinforcing HA hydrogels greatly enhanced the mechanical properties. • Self-reinforcing HA hydrogels prolonged the sustained delivery of BSA. • The self-reinforcing mechanism and BSA diffusion mechanism were discussed. • Self-reinforcing HA hydrogels had no cytotoxicity to 3T3 fibroblast cells.

  11. Both hyaluronan and collagen type II keep proteoglycan 4 (lubricin) at the cartilage surface in a condition that provides low friction during boundary lubrication.

    Science.gov (United States)

    Majd, Sara Ehsani; Kuijer, Roel; Köwitsch, Alexander; Groth, Thomas; Schmidt, Tannin A; Sharma, Prashant K

    2014-12-09

    Wear resistant and ultralow friction in synovial joints is the outcome of a sophisticated synergy between the major macromolecules of the synovial fluid, e.g., hyaluronan (HA) and proteoglycan 4 (PRG4), with collagen type II fibrils and other non-collagenous macromolecules of the cartilage superficial zone (SZ). This study aimed at better understanding the mechanism of PRG4 localization at the cartilage surface. We show direct interactions between surface bound HA and freely floating PRG4 using the quartz crystal microbalance with dissipation (QCM-D). Freely floating PRG4 was also shown to bind with surface bound collagen type II fibrils. Albumin, the most abundant protein of the synovial fluid, effectively blocked the adsorption of PRG4 with HA, through interaction with C and N terminals on PRG4, but not that of PRG4 with collagen type II fibrils. The above results indicate that collagen type II fibrils strongly contribute in keeping PRG4 in the SZ during cartilage articulation in situ. Furthermore, PRG4 molecules adsorbed very well on mimicked SZ of absorbed HA molecules with entangled collagen type II fibrils and albumin was not able to block this interaction. In this last condition PRG4 adsorption resulted in a coefficient of friction (COF) of the same order of magnitude as the COF of natural cartilage, measured with an atomic force microscope in lateral mode.

  12. Hyaluronan-Phosphatidylethanolamine Polymers Form Pericellular Coats on Keratinocytes and Promote Basal Keratinocyte Proliferation

    Directory of Open Access Journals (Sweden)

    Caitlin J. Symonette

    2014-01-01

    Full Text Available Aged keratinocytes have diminished proliferative capacity and hyaluronan (HA cell coats, which are losses that contribute to atrophic skin characterized by reduced barrier and repair functions. We formulated HA-phospholipid (phosphatidylethanolamine, HA-PE polymers that form pericellular coats around cultured dermal fibroblasts independently of CD44 or RHAMM display. We investigated the ability of these HA-PE polymers to penetrate into aged mouse skin and restore epidermal function in vivo. Topically applied Alexa647-HA-PE penetrated into the epidermis and dermis, where it associated with both keratinocytes and fibroblasts. In contrast, Alexa647-HA was largely retained in the outer cornified layer of the epidermis and quantification of fluorescence confirmed that significantly more Alexa647-HA-PE penetrated into and was retained within the epidermis than Alexa647-HA. Multiple topical applications of HA-PE to shaved mouse skin significantly stimulated basal keratinocyte proliferation and epidermal thickness compared to HA or vehicle cream alone. HA-PE had no detectable effect on keratinocyte differentiation and did not promote local or systemic inflammation. These effects of HA-PE polymers are similar to those reported for endogenous epidermal HA in youthful skin and show that topical application of HA-PE polymers can restore some of the impaired functions of aged epidermis.

  13. Towards a structure for a TSG-6.hyaluronan complex by modeling and NMR spectroscopy: insights into other members of the link module superfamily.

    Science.gov (United States)

    Blundell, Charles D; Almond, Andrew; Mahoney, David J; DeAngelis, Paul L; Campbell, Iain D; Day, Anthony J

    2005-05-06

    The Link module from human TSG-6, a hyaladherin with roles in ovulation and inflammation, has a hyaluronan (HA)-binding groove containing two adjacent tyrosine residues that are likely to form CH-pi stacking interactions with sequential rings in the sugar. We have used this observation to construct a model of a protein.HA complex, which was then tested against existing experimental information and by acquisition of new NMR data sets of [(13)C, (15)N]HA (8-mer) complexed with unlabeled protein. A major finding of this analysis was that acetamido side chains of two GlcNAc rings fit into hydrophobic pockets on either side of the adjacent tyrosines, providing a selectivity mechanism of HA over other polysaccharides. Furthermore, two basic residues have a separation that matches that of glucuronic acids in the sugar, consistent with the formation of salt bridges; NMR experiments at a range of pH values identified protein groups that titrate due to their proximity to a free carboxylate in HA. Sequence alignment and construction of homology models for all human Link modules in their HA-bound states revealed that many of these features are conserved across the superfamily, thus allowing the prediction of functionally important residues. In the case of cartilage link protein, its two Link modules were docked together (using bound HA as a guide), identifying hydrophobic residues likely to form an intra-Link module interface as well as amino acids that could be involved in supporting intermolecular interactions between link proteins and chondroitin sulfate proteoglycans. Here, we propose a mechanism for ternary complex formation that generates higher order helical structures, as may exist in cartilage aggregates.

  14. Hyaluronan signaling during ozone-induced lung injury requires TLR4, MyD88, and TIRAP.

    Directory of Open Access Journals (Sweden)

    Zhuowei Li

    Full Text Available Ozone exposure is associated with exacerbation of reactive airways disease. We have previously reported that the damage-associated molecular pattern, hyaluronan, is required for the complete biological response to ambient ozone and that hyaluronan fragments signal through toll-like receptor 4 (TLR4. In this study, we further investigated the role of TLR4 adaptors in ozone-induced airway hyperresponsiveness (AHR and the direct response to hyaluronan fragments (HA. Using a murine model of AHR, C57BL/6J, TLR4-/-, MyD88-/-, and TIRAP-/- mice were characterized for AHR after exposure to either ozone (1 ppm × 3 h or HA fragments. Animals were characterized for AHR with methacholine challenge, cellular inflammation, lung injury, and production of pro-inflammatory cytokines. Ozone-exposed C57BL/6J mice developed cellular inflammation, lung injury, pro-inflammatory cytokines, and AHR, while mice deficient in TLR4, MyD88 or TIRAP demonstrated both reduced AHR and reduced levels of pro-inflammatory cytokines including TNFα, IL-1β, MCP-1, IL-6 and KC. The level of hyaluronan was increased after inhalation of ozone in each strain of mice. Direct challenge of mice to hyaluronan resulted in AHR in C57BL/6J mice, but not in TLR4-/-, MyD88-/-, or TIRAP-/- mice. HA-induced cytokine production in wild-type mice was significantly reduced in TLR4-/-, MyD88-/-, or TIRAP-/- mice. In conclusion, our findings support that ozone-induced airway hyperresponsiveness is dependent on the HA-TLR4-MyD88-TIRAP signaling pathway.

  15. Dietary flavonoid fisetin increases abundance of high-molecular-mass hyaluronan conferring resistance to prostate oncogenesis.

    Science.gov (United States)

    Lall, Rahul K; Syed, Deeba N; Khan, Mohammad Imran; Adhami, Vaqar M; Gong, Yuansheng; Lucey, John A; Mukhtar, Hasan

    2016-09-01

    We and others have shown previously that fisetin, a plant flavonoid, has therapeutic potential against many cancer types. Here, we examined the probable mechanism of its action in prostate cancer (PCa) using a global metabolomics approach. HPLC-ESI-MS analysis of tumor xenografts from fisetin-treated animals identified several metabolic targets with hyaluronan (HA) as the most affected. Efficacy of fisetin on HA was then evaluated in vitro and also in vivo in the transgenic TRAMP mouse model of PCa. Size exclusion chromatography-multiangle laser light scattering (SEC-MALS) was performed to analyze the molar mass (Mw) distribution of HA. Fisetin treatment downregulated intracellular and secreted HA levels both in vitro and in vivo Fisetin inhibited HA synthesis and degradation enzymes, which led to cessation of HA synthesis and also repressed the degradation of the available high-molecular-mass (HMM)-HA. SEC-MALS analysis of intact HA fragment size revealed that cells and animals have more abundance of HMM-HA and less of low-molecular-mass (LMM)-HA upon fisetin treatment. Elevated HA levels have been shown to be associated with disease progression in certain cancer types. Biological responses triggered by HA mainly depend on the HA polymer length where HMM-HA represses mitogenic signaling and has anti-inflammatory properties whereas LMM-HA promotes proliferation and inflammation. Similarly, Mw analysis of secreted HA fragment size revealed less HMM-HA is secreted that allowed more HMM-HA to be retained within the cells and tissues. Our findings establish that fisetin is an effective, non-toxic, potent HA synthesis inhibitor, which increases abundance of antiangiogenic HMM-HA and could be used for the management of PCa. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Increased concentration of hyaluronan in tears after soaking contact lenses in Biotrue multipurpose solution

    Directory of Open Access Journals (Sweden)

    Scheuer CA

    2016-10-01

    Full Text Available Catherine A Scheuer, Marjorie J Rah, William T Reindel Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: This study was conducted to determine 1 the concentration of hyaluronan (HA in the tear films of contact lens (CL wearers versus non-CL wearers and 2 whether HA sorbed from Biotrue, an HA-containing multipurpose solution (MPS, onto senofilcon A lenses affects the concentration of HA in tears after 2 hours of wear.Patients and methods: Tears of habitual CL wearers and non-CL wearers were collected on Schirmer strips at baseline and after 2 hours of wear of senofilcon A CLs that had first been either rinsed with Sensitive Eyes Saline or soaked in Biotrue MPS for 14 hours. HA concentrations were measured by enzyme-linked immunosorbent assay (ELISA and adjusted for sample volumes.Results: No difference in baseline concentrations of HA in tears was found between CL wearers and non-CL wearers (P=0.07, nor between males and females (P=0.06. However, age was significantly negatively associated with HA concentration (P<0.01, and mostly, CL wear contributed to a significant association (P<0.01. Among saline-rinsed CL wearers, no change in HA concentration in tears was observed after 2 hours of wear (P=0.38. By contrast, a significant increase in HA concentration was observed in the tears from eyes that had worn CLs soaked in Biotrue MPS when compared to baseline (P=0.01 or to saline-rinsed control (P=0.03.Conclusion: 1 In this study population, no difference in baseline concentration of HA was observed between CL wearers and non-CL wearers, and 2 after 2 hours of wear of senofilcon A lenses that were soaked in Biotrue MPS, HA concentrations in the tear films of CL wearers increased. Keywords: contact lens, dry eye, hyaluronan, MPS

  17. Biomimetic hemocompatible coatings through immobilization of hyaluronan derivatives on metal surfaces.

    Science.gov (United States)

    Thierry, Benjamin; Winnik, Françoise M; Merhi, Yahye; Griesser, Hans J; Tabrizian, Maryam

    2008-10-21

    Biomimetic coatings offer exciting options to modulate the biocompatibility of biomaterials. The challenge is to create surfaces that undergo specific interactions with cells without promoting nonspecific fouling. This work reports an innovative approach toward biomimetic surfaces based on the covalent immobilization of a carboxylate terminated PEGylated hyaluronan (HA-PEG) onto plasma functionalized NiTi alloy surfaces. The metal substrates were aminated via two different plasma functionalization processes. Hyaluronan, a natural glycosaminoglycan and the major constituent of the extracellular matrix, was grafted to the substrates by reaction of the surface amines with the carboxylic acid terminated PEG spacer using carbodiimide chemistry. The surface modification was monitored at each step by X-ray photoelectron spectroscopy (XPS). HA-immobilized surfaces displayed increased hydrophilicity and reduced fouling, compared to bare surfaces, when exposed to human platelets (PLT) in an in vitro assay with radiolabeled platelets (204.1 +/- 123.8 x 10 (3) PLT/cm (2) vs 538.5 +/- 100.5 x 10 (3) PLT/cm (2) for bare metal, p surfaces were successfully created as demonstrated by XPS chemical imaging. The bioactive surfaces described present unique features, which result from the synergy between the intrinsic biological properties of hyaluronan and the chemical composition and morphology of the polymer layer immobilized on a metal surface.

  18. Immunohistochemical localization and expression of the hyaluronan receptor CD44 in the epithelium of the pig oviduct during oestrus.

    Science.gov (United States)

    Tienthai, P; Yokoo, M; Kimura, N; Heldin, P; Sato, E; Rodriguez-Martinez, H

    2003-01-01

    Hyaluronan is related to essential reproductive processes in pigs. Hyaluronan produced by cumulus cells builds, via specific cell surface receptors, an extracellular matrix responsible for cumulus cell cloud expansion during final oocyte maturation, a preparatory event for ovulation and fertilization. In addition, hyaluronan that has been localized in the pig oviduct both in the intraluminal fluid and on the surface of the lining epithelium of the preovulatory sperm reservoir, has proven beneficial during in vitro fertilization and embryo culture, thus indicating that it has a role in vivo. This study monitored the immunolocalization, protein determination and gene expression of the major cell surface hyaluronan receptor CD44 in the epithelial lining of the pig oviduct during selected stages of standing oestrus, in relation to spontaneous ovulation. The CD44 immunostaining in the lining epithelium was localized to the surface membrane and the supranuclear domain of mainly the secretory cells, particularly in the sperm reservoir of both treatment (inseminated) and control (non-inseminated) specimens. Up to four hyaluronan-binding protein (HABP) bands (60, 90, 100 and 200 kDa) were detected in the tubal epithelium, and the 200 kDa band was determined as CD44 by immunoblotting. The expression of CD44 mRNA was higher before than after ovulation (P AIJ) of control animals was higher than in those that were inseminated (P AIJ, respectively). The results demonstrate for the first time that the specific hyaluronan receptor CD44 is expressed by the oviduct epithelial cells during spontaneous oestrus, and is particularly abundant in the sperm reservoir before ovulation. Presence of spermatozoa in this segment seemed to downregulate the receptor. The variation in the expression of CD44 in relation to spontaneous ovulation and the presence of spermatozoa indicate that the hyaluronan CD44-signalling pathway may play a role in oviduct function during sperm storage and

  19. Therapeutic effects of high molecular weight hyaluronan injections for tendinopathy in a rat model.

    Science.gov (United States)

    Yoshida, Mamoru; Funasaki, Hiroki; Kubota, Makoto; Marumo, Keishi

    2015-01-01

    Tendinopathy is the most common tendon disorder. The etiology is still uncertain, and the disorder poses many therapeutic problems. In a few clinical studies, analgesic effects of high molecular weight hyaluronan (HMW HA) injections were observed, but the underlying mechanisms were not elucidated. In the present study, we analyzed the therapeutic effects of hyaluronan injections for tendinopathy in an animal model. We made the tendinopathy rat model using a rodent treadmill machine. Rats with tendinopathy were injected with HMW HA (HA group), normal saline (NS group), or nothing (control group) into the space between the patellar tendon and the fat pad bilaterally, or were injected with HMW HA into the right knees and with saline to the left knees (HA/NS group), 5 times every 4 days. To assess the pain-relieving effect of HA, the spontaneous locomotor activities at night (12 h) and weight bearing of hind paws were measured every day. Histological sections of the patellar tendon stained with hematoxylin-eosin or prepared by TdT-mediated dUTP nick end labeling were microscopically analyzed. The number of spontaneous locomotor activities in the HA group was significantly larger than those in NS or control groups, and in the HA group they recovered up to a healthy level. The percent weight distribution of the right hind paws was significantly increased along with the number of injections. On histologic examinations, the numbers of microtears, laminations, or apoptotic cells in the patellar tendons in the HA group were significantly lower than those in the NS or the control groups. The injections of HMW HA were effective for pain relief and for partial restoration of the patellar tendon in our tendinopathy rat model, and thus may become an effective therapeutic modality for the disease.

  20. Catabolism of hyaluronan: involvement of transition metals

    OpenAIRE

    Šoltés, Ladislav; Kogan, Grigorij

    2009-01-01

    One of the very complex structures in the vertebrates is the joint. The main component of the joint is the synovial fluid with its high-molar-mass glycosaminoglycan hyaluronan, which turnover is approximately twelve hours. Since the synovial fluid does not contain any hyaluronidases, the fast hyaluronan catabolism is caused primarily by reductive-oxidative processes. Eight transition metals – V23, Mn25, Fe26, Co27, Ni28, Cu29, Zn30, and Mo42 – naturally occurring in living organism are essent...

  1. Hyaluronan and phospholipid association in biolubrication

    DEFF Research Database (Denmark)

    Wang, Min; Liu, Chao; Thormann, Esben

    2013-01-01

    load bearing capacity. With DPPC as the last adsorbed component, a friction coefficient of 0.01 was found up to pressures significantly above what is encountered in healthy synovial joints. Hyaluronan as the last added component increases the friction coefficient to 0.03 and decreases the load bearing...... capacity somewhat (but still above what is needed in the synovial joint). Our data demonstrate that self-assembly structures formed by hyaluronan and phospholipids at interfaces are efficient aqueous lubricants, and it seems plausible that such self-assembly structures contribute to the exceptional...

  2. Chromosomal localization of the human and mouse hyaluronan synthase genes

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, A.P.; McDonald, J.A. [Mayo Clinic Scottsdale, AZ (United States); Seldin, M.F. [Univ. of California Davis, CA (United States)] [and others

    1997-05-01

    We have recently identified a new vertebrate gene family encoding putative hyaluronan (HA) synthases. Three highly conserved related genes have been identified, designated HAS1, HAS2, and HAS3 in humans and Has1, Has2, and Has3 in the mouse. All three genes encode predicted plasma membrane proteins with multiple transmembrane domains and approximately 25% amino acid sequence identity to the Streptococcus pyogenes HA synthase, HasA. Furthermore, expression of any one HAS gene in transfected mammalian cells leads to high levels of HA biosynthesis. We now report the chromosomal localization of the three HAS genes in human and in mouse. The genes localized to three different positions within both the human and the mouse genomes. HAS1 was localized to the human chromosome 19q13.3-q13.4 boundary and Has1 to mouse Chr 17. HAS2 was localized to human chromosome 8q24.12 and Has2 to mouse Chr 15. HAS3 was localized to human chromosome 16q22.1 and Has3 to mouse Chr 8. The map position for HAS1 reinforces the recently reported relationship between a small region of human chromosome 19q and proximal mouse chromosome 17. HAS2 mapped outside the predicted critical region delineated for the Langer-Giedion syndrome and can thus be excluded as a candidate gene for this genetic syndrome. 33 refs., 2 figs.

  3. Synthesis and characterization of a Hyaluronan-polyethylene copolymer for biomedical applications.

    Science.gov (United States)

    Oldinski, Rachael A; Cranson, Cody N; James, Susan P

    2010-08-01

    Hyaluronan (HA)-based biomaterials are of interest for bone and cartilage tissue engineering because HA plays an important role in orthopedic tissue development, function, and repair. The goal of this project was to develop a biomaterial that incorporated the constituents of both a hydrogel and a hydrophobic polymer for biomedical applications. A series of amphiphilic graft copolymers consisting of HA, a glycosaminoglycan, and high-density polyethylene (HDPE), that is, HA-co-HDPE, were fabricated. The chemical characteristics, physical and viscoelastic properties, and cytocompatibility of novel HA-co-HDPE materials were characterized via Fourier Transform infrared (FTIR) spectroscopy, solid state nuclear magnetic resonance (ssNMR) spectroscopy, differential scanning calorimetry (DSC), dynamic shear testing, and an in vitro human osteoblast cell study. The esterification reaction between HA and functionalized HDPE resulted in semicrystalline, insoluble powder. The dynamic shear properties of HA-co-HDPE concentrated solutions were more like natural proteoglycans than the HA control. HA-co-HDPE was successfully compression molded into disks that swelled upon hydration. Osteoblasts were viable and expressed the osteoblast phenotype after 7 days of culture on HA-co-HDPE materials. These HA-co-HDPE materials may have several biomaterial applications in saline suspension or molded form, including orthopedic tissue repair.

  4. Influence of hyaluronan on endometrial receptivity and embryo attachment in sheep.

    Science.gov (United States)

    Marei, Waleed F A; Wathes, D Claire; Raheem, Kabir A; Mohey-Elsaeed, Omnia; Ghafari, Fataneh; Fouladi-Nashta, Ali A

    2016-10-11

    An increasing number of reports suggests a role of hyaluronan (HA) in female reproduction and interest in its application in assisted reproduction is rising. However, there are contrasting data about the effectiveness of adding HA to the embryo-transfer medium on improving pregnancy rates. Using sheep as an experimental model, the studies reported here analysed the impact of HA infusion into the uterus on embryo attachment to uterine luminal epithelium (LE) and expression of selected markers of uterine receptivity. On Day 14 after natural mating (pre-attachment), uterine horns were infused with either (n=4 each): PBS (control), HA (1mg mL-1), HA+hyaluronidase 2 (Hyal2; 300IU mL-1) or 4-methyl-umbelliferone (HA-synthesis inhibitor; 4MU, 1mM). HA immunostaining on uterine sections collected on Day 17 was negative in the 4MU group and weak in the HA+Hyal2 group. In contrast to 4MU, which resulted in 100% attachment, HA infusion blocked embryo attachment in all treated animals. This was accompanied by the disappearance of mucin 1 and increased expression of osteopontin and CD44v6 in the LE of uteri with attached embryos. In conclusion, the presence of HA at the embryo-maternal interface during embryo implantation resulted in reduced endometrial receptivity and inhibited the interaction of trophoblasts with the LE, whereas clearance of HA favoured embryo attachment.

  5. High-molecular-mass hyaluronan mediates the cancer resistance of the naked mole rat.

    Science.gov (United States)

    Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

    2013-07-18

    The naked mole rat (Heterocephalus glaber) displays exceptional longevity, with a maximum lifespan exceeding 30 years. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years. In addition to their longevity, naked mole rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer. Here we identify a mechanism responsible for the naked mole rat's cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high-molecular-mass hyaluronan (HA), which is over five times larger than human or mouse HA. This high-molecular-mass HA accumulates abundantly in naked mole-rat tissues owing to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signalling, as they have a higher affinity to HA compared with mouse or human cells. Perturbation of the signalling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high-molecular-mass HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, HYAL2, naked mole-rat cells become susceptible to malignant transformation and readily form tumours in mice. We speculate that naked mole rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species.

  6. High molecular weight hyaluronan mediates the cancer resistance of the naked mole-rat

    Science.gov (United States)

    Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

    2013-01-01

    The naked mole-rat displays exceptional longevity, with a maximum lifespan exceeding 30 years1–3. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole-rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years4,5. In addition to their longevity, naked mole-rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer2,6. Here we identify a mechanism responsible for the naked mole-rat’s cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high molecular weight hyaluronan (HA), which is over five times larger than human or mouse HA. This high molecular weight HA accumulates abundantly in naked mole rat tissues due to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signaling, as the naked mole rat cells have a higher affinity to HA than the mouse or human cells. Perturbation of the signaling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high molecular weight HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, Hyal2, naked mole-rat cells become susceptible to malignant transformation and readily form tumors in mice. We speculate that naked mole-rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species. PMID:23783513

  7. EFFECTS OF HYALURONAN ON THREE-DIMENSIONAL MICROARCHITECTURE OF SUBCHONDRAL BONE TISSUES IN GUINEA PIG PRIMARY OSTEOARTHROSIS

    DEFF Research Database (Denmark)

    Ding, Ming

    Introduction: It is not known whether hyaluronan (HA) has any effect on the underlying subchondral bone tissues. This study was to investigate the effects of high molecular weight HA (1.5x106 Daltons) intra-articular injection on subchondral bone tissues. Methods: Fifty-six male guinea pigs (6......-term study, these latter changes were more pronounced, with an additionally significant decrease in connectivity and bone surface density. HA groups had greater bone mineral concentration and mineral density, lower collagen to mineral ratio, and preserved the mechanical properties of cancellous bone....... The effects of HA on cartilage and subchondral bone were maintained when HA treatment was discontinued. Discussion: Significant positive effects of high molecular weight HA on the articular cartilage and subchondral bone tissues were seen. HA protects against OA-related cartilage degradation to almost normal...

  8. Anti-inflammatory effects of hyaluronan in arthritis therapy: Not just for viscosity

    Directory of Open Access Journals (Sweden)

    Kayo Masuko

    2009-04-01

    Full Text Available Kayo Masuko1, Minako Murata2, Kazuo Yudoh2, Tomohiro Kato1, Hiroshi Nakamura31Department of Biochemistry; 2Institute of Medical Science, St. Marianna University School of Medicine, Kawasaki-shi, Kanagawa, Japan; 3Department of Joint Disease and Rheumatism, Nippon Medical School, Bunkyo-ku, Tokyo, JapanAbstract: Hyaluronic acid (HA has been widely used for viscosupplementation of diseased or aged articular joints. However, recent investigations have revealed the active anti-inflammatory or chondroprotective effect of HA, suggesting its potential role in attenuation of joint damage. In particular, interactions between HA and other inflammatory mediators are attracting interest. This review summarizes several aspects of recent investigations of the anti-inflammatory effects of HA in arthritis.Keywords: hyaluronan, inflammation, chondroprotection

  9. Both Hyaluronan and Collagen Type II Keep Proteoglycan 4 (Lubricin) at the Cartilage Surface in a Condition That Provides Low Friction during Boundary Lubrication

    NARCIS (Netherlands)

    Majd, Sara Ehsani; Kuijer, Roel; Koewitsch, Alexander; Groth, Thomas; Schmidt, Tannin A.; Sharma, Prashant K.

    2014-01-01

    Wear resistant and ultralow friction in synovial joints is the outcome of a sophisticated synergy between the major macromolecules of the synovial fluid, e.g., hyaluronan (HA) and proteoglycan 4 (PRG4), with collagen type II fibrils and other non-collagenous macromolecules of the cartilage superfici

  10. Growth factor PDGF-BB stimulates cultured cardiomyocytes to synthesize the extracellular matrix component hyaluronan.

    Directory of Open Access Journals (Sweden)

    Urban Hellman

    Full Text Available BACKGROUND: Hyaluronan (HA is a glycosaminoglycan located in the interstitial space which is essential for both structural and cell regulatory functions in connective tissue. We have previously shown that HA synthesis is up-regulated in a rat model of experimental cardiac hypertrophy and that cardiac tissue utilizes two different HA synthases in the hypertrophic process. Cardiomyocytes and fibroblasts are two major cell types in heart tissue. The fibroblasts are known to produce HA, but it has been unclear if cardiomyocytes share the same feature, and whether or not the different HA synthases are activated in the different cell types. METHODOLOGY/PRINCIPAL FINDINGS: This study shows, for the first time that cardiomyocytes can produce HA. Cardiomyocytes (HL-1 and fibroblasts (NIH 3T3 were cultivated in absence or presence of the growth factors FGF2, PDGF-BB and TGFB2. HA concentration was quantified by ELISA, and the size of HA was estimated using dynamic light scattering. Cardiomyocytes synthesized HA but only when stimulated by PDGF-BB, whereas fibroblasts synthesized HA without addition of growth factors as well as when stimulated by any of the three growth factors. When fibroblasts were stimulated by the growth factors, reverse dose dependence was observed, where the highest dose induced the least amount of HA. With the exception of TGFB2, a trend of reverse dose dependence of HA size was also observed. CONCLUSIONS/SIGNIFICANCE: Co-cultivation of cardiomyocytes and fibroblasts (80%/20% increased HA concentration far more that can be explained by HA synthesis by the two cell types separately, revealing a crosstalk between cardiomyocytes and fibroblasts that induces HA synthesis. We conclude that dynamic changes of the myocardium, such as in cardiac hypertrophy, do not depend on the cardiomyocyte alone, but are achieved when both cardiomyocytes and fibroblasts are present.

  11. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy

    Science.gov (United States)

    Yang, Rui-Meng; Fu, Chao-Ping; Fang, Jin-Zhi; Xu, Xiang-Dong; Wei, Xin-Hua; Tang, Wen-Jie; Jiang, Xin-Qing; Zhang, Li-Ming

    2017-01-01

    Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA)-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs), which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhancement on T2-weighted magnetic resonance imaging and photothermal effect targeted CD44 HA receptor-overexpressing breast cancer. All these results indicated that HA-SPIONs have great potential for effective diagnosis and treatment of cancer. PMID:28096667

  12. Increased concentration of hyaluronan in tears after soaking contact lenses in Biotrue multipurpose solution

    Science.gov (United States)

    Scheuer, Catherine A; Rah, Marjorie J; Reindel, William T

    2016-01-01

    Purpose This study was conducted to determine 1) the concentration of hyaluronan (HA) in the tear films of contact lens (CL) wearers versus non-CL wearers and 2) whether HA sorbed from Biotrue, an HA-containing multipurpose solution (MPS), onto senofilcon A lenses affects the concentration of HA in tears after 2 hours of wear. Patients and methods Tears of habitual CL wearers and non-CL wearers were collected on Schirmer strips at baseline and after 2 hours of wear of senofilcon A CLs that had first been either rinsed with Sensitive Eyes Saline or soaked in Biotrue MPS for 14 hours. HA concentrations were measured by enzyme-linked immunosorbent assay (ELISA) and adjusted for sample volumes. Results No difference in baseline concentrations of HA in tears was found between CL wearers and non-CL wearers (P=0.07), nor between males and females (P=0.06). However, age was significantly negatively associated with HA concentration (Peyes that had worn CLs soaked in Biotrue MPS when compared to baseline (P=0.01) or to saline-rinsed control (P=0.03). Conclusion 1) In this study population, no difference in baseline concentration of HA was observed between CL wearers and non-CL wearers, and 2) after 2 hours of wear of senofilcon A lenses that were soaked in Biotrue MPS, HA concentrations in the tear films of CL wearers increased. PMID:27784983

  13. Specific sizes of hyaluronan oligosaccharides stimulate fibroblast migration and excisional wound repair.

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    Cornelia Tolg

    Full Text Available The extracellular matrix polysaccharide hyaluronan (HA plays a key role in both fibrotic and regenerative tissue repair. Accumulation of high molecular weight HA is typical of regenerative repair, which is associated with minimal inflammation and fibrosis, while fragmentation of HA is typical of postnatal wounds, which heal in the presence of inflammation and transient fibrosis. It is generally considered that HA oligosaccharides and fragments of a wide size range support these processes of adult, fibrotic wound repair yet the consequences of sized HA fragments/oligosaccharides to each repair stage is not well characterized. Here, we compared the effects of native HA, HA oligosaccharide mixtures and individual sizes (4-10 mer oligosaccharides, 5 and, 40 kDa of HA oligosaccharides and fragments, on fibroblast migration in scratch wound assays and on excisional skin wound repair in vivo. We confirm that 4-10 mer mixtures significantly stimulated scratch wound repair and further report that only the 6 and 8 mer oligosaccharides in this mixture are responsible for this effect. The HA 6 mer promoted wound closure, accumulation of wound M1 and M2 macrophages and the M2 cytokine TGFβ1, but did not increase myofibroblast differentiation. The effect of 6 mer HA on wound closure required both RHAMM and CD44 expression. In contrast, The 40 kDa HA fragment inhibited wound closure, increased the number of wound macrophages but had no effect on TGFβ1 accumulation or subsequent fibrosis. These results show that specific sizes of HA polymer have unique effects on postnatal wound repair. The ability of 6 mer HA to promote wound closure and inflammation resolution without increased myofibroblast differentiation suggests that this HA oligosaccharide could be useful for treatment of delayed or inefficient wound repair where minimal fibrosis is advantageous.

  14. HA-Coated Implant

    DEFF Research Database (Denmark)

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    The goal of osseointegration of orthopedic and dental implants is the rapid achievement of a mechanically stable and long lasting fixation between living bone and the implant surface. In total joint replacements of cementless designs, coatings of calcium phosphates were introduced as a means...... of improving the fixation of implants. Of these, hydroxyapatite (HA) is the most widely used and most extensively investigated. HA is highly osseoconductive, and the positive effect is well documented in both basic and long-term clinical research [1–6]. This chapter describes experimental and clinical studies...... evaluating bone-implant fixation with HA coatings....

  15. Structural profiling and biological performance of phospholipid-hyaluronan functionalized single-walled carbon nanotubes

    DEFF Research Database (Denmark)

    Dvash, Ram; Khatchatouriants, Artium; Solmesky, Leonardo J

    2013-01-01

    In spite of significant insolubility and toxicity, carbon nanotubes (CNTs) erupt into the biomedical research, and create an increasing interest in the field of nanomedicine. Single-walled CNTs (SWCNTs) are highly hydrophobic and have been shown to be toxic while systemically administrated. Thus......, SWCNTs have to be functionalized to render water solubility and biocompatibility. Herein, we introduce a method for functionalizing SWCNT using phospholipids (PL) conjugated to hyaluronan (HA), a hydrophilic glycosaminoglycan, with known receptors on many types of cancer and immune cells...

  16. Haïti

    Directory of Open Access Journals (Sweden)

    Marc Pabois

    2012-04-01

    Full Text Available Figure 1Carte schématique de Haïti. Atelier de photogrammétrie de l’Inventaire généralMichel MaumontTrois missions ont eu lieu à Haïti, la première en 1997, les deux autres en 1998. Le Directeur du patrimoine à Haïti et le Directeur de la division du patrimoine culturel à l’Unesco ont ainsi fait appel au Ministère de la Culture afin de faire bénéficier Haïti de l’expérience acquise par la France dans le domaine de l’Inventaire. L’objectif de la première mission était d’analyser avec les respo...

  17. Increased Levels of Type I and III Collagen and Hyaluronan in Scleroderma Skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Heickendorff, Lene; L, Risteli

    1997-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) and the carboxyterminal propeptide of type I procollagen (PICP) and hyaluronan (HA) were measured in plasma and suction blister fluid from 13 systemic sclerosis patients and 11 healthy volunteers. Suction blisters and skin biopsies were...... from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin of patients. The median value of suction blister PIIINP from the transition zone was 38% higher than suction blister PIIINP from uninvolved skin. PIIINP was localized to the dermis by immunohistochemical...... techniques. PICP and HA levels in blisters from the transition zone were 87% and 53%, respectively, above the levels measured in uninvolved skin. Furthermore, PICP and HA blister levels from the transition zone were 67% and 63%, respectively, higher than the levels measured in healthy volunteers. In plasma...

  18. Increased Levels of Type I and III Collagen and Hyaluronan in Scleroderma Skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Heickendorff, Lene; L, Risteli

    1997-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) and the carboxyterminal propeptide of type I procollagen (PICP) and hyaluronan (HA) were measured in plasma and suction blister fluid from 13 systemic sclerosis patients and 11 healthy volunteers. Suction blisters and skin biopsies were...... from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin of patients. The median value of suction blister PIIINP from the transition zone was 38% higher than suction blister PIIINP from uninvolved skin. PIIINP was localized to the dermis by immunohistochemical...... techniques. PICP and HA levels in blisters from the transition zone were 87% and 53%, respectively, above the levels measured in uninvolved skin. Furthermore, PICP and HA blister levels from the transition zone were 67% and 63%, respectively, higher than the levels measured in healthy volunteers. In plasma...

  19. Role of Versican, Hyaluronan and CD44 in Ovarian Cancer Metastasis

    Directory of Open Access Journals (Sweden)

    Miranda P. Ween

    2011-01-01

    Full Text Available There is increasing evidence to suggest that extracellular matrix (ECM components play an active role in tumor progression and are an important determinant for the growth and progression of solid tumors. Tumor cells interfere with the normal programming of ECM biosynthesis and can extensively modify the structure and composition of the matrix. In ovarian cancer alterations in the extracellular environment are critical for tumor initiation and progression and intra-peritoneal dissemination. ECM molecules including versican and hyaluronan (HA which interacts with the HA receptor, CD44, have been shown to play critical roles in ovarian cancer metastasis. This review focuses on versican, HA, and CD44 and their potential as therapeutic targets for ovarian cancer.

  20. BMP-2 induces versican and hyaluronan that contribute to post-EMT AV cushion cell migration.

    Science.gov (United States)

    Inai, Kei; Burnside, Jessica L; Hoffman, Stanley; Toole, Bryan P; Sugi, Yukiko

    2013-01-01

    Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV) valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM) components, versican and hyaluronan (HA), and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH) stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC) aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions.

  1. BMP-2 induces versican and hyaluronan that contribute to post-EMT AV cushion cell migration.

    Directory of Open Access Journals (Sweden)

    Kei Inai

    Full Text Available Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM components, versican and hyaluronan (HA, and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions.

  2. Synthesis of hyaluronan haloacetates and biology of novel cross-linker-free synthetic extracellular matrix hydrogels.

    Science.gov (United States)

    Serban, Monica A; Prestwich, Glenn D

    2007-09-01

    Hyaluronan (HA) derivatives containing thiol-reactive electrophilic esters were prepared to react with thiol-modified macromolecules to give cross-linker-free hydrogels. Specifically, HA was converted to two haloacetate derivatives, HA bromoacetate (HABA) and HA iodoacetate (HAIA). In cytotoxicity assays, these reactive macromolecules predictably induced cell death in a dose-dependent manner. Cross-linker-free synthetic extracellular matrix (sECM) hydrogels were prepared by thiol alkylation using HAIA and HABA as polyvalent electrophiles and thiol-modified HA (CMHA-S) with or without thiol-modified gelatin (Gtn-DTPH) as polyvalent nucleophiles. When primary human fibroblasts were seeded on the surface of the sECMs containing only the electrophilic HA haloacetate and nucleophilic CMHA-S components, no significant cytoadherence was observed. Cell attachment and viability was 17% (HABA) to 30% (HAIA) lower on HA haloacetate cross-linked hydrogels than on CMHA-S that had been oxidatively cross-linked via disulfide-bonds. In contrast, sECMs that included Gtn-DTPH allowed fibroblasts to attach, spread, and proliferate. Taken together, the HA haloacetates are attractive candidates for producing cross-linker-free sECM biomaterials that can function either as anti-adhesive barriers or as cytoadhesive sECMs for cell culture in pseudo-3-D.

  3. Neocartilage formation from mesenchymal stem cells grown in type II collagen-hyaluronan composite scaffolds.

    Science.gov (United States)

    Yeh, Hsi-Yi; Lin, Ting-Yu; Lin, Chen-Huan; Yen, B Linju; Tsai, Ching-Lin; Hsu, Shan-Hui

    2013-01-01

    Three-dimensional (3D) collagen type II-hyaluronan (HA) composite scaffolds (CII-HA) which mimics the extracellular environment of natural cartilage were fabricated in this study. Rheological measurements demonstrated that the incorporation of HA increased the compression modulus of the scaffolds. An initial in vitro evaluation showed that scaffolds seeded with porcine chondrocytes formed cartilaginous-like tissue after 8 weeks, and HA functioned to promote the growth of chondrocytes into scaffolds. Placenta-derived multipotent cells (PDMC) and gingival fibroblasts (GF) were seeded on tissue culture polystyrene (TCPS), CII-HA films, and small intestinal submucosa (SIS) sheets for comparing their chondrogenesis differentiation potentials with those of adipose-derived adult stem cells (ADAS) and bone marrow-derived mesenchymal stem cells (BMSC). Among different cells, PDMC showed the greatest chondrogenic differentiation potential on both CII-HA films and SIS sheets upon TGF-β3 induction, followed by GF. This was evidenced by the up-regulation of chondrogenic genes (Sox9, aggrecan, and collagen type II), which was not observed for cells grown on TCPS. This finding suggested the essential role of substrate materials in the chondrogenic differentiation of PDMC and GF. Neocartilage formation was more obvious in both PDMC and GF cells plated on CII-HA composite scaffolds vs. 8-layer SIS at 28 days in vitro. Finally, implantation of PDMC/CII-HA constructs into NOD-SCID mice confirmed the formation of tissue-engineered cartilage in vivo.

  4. Identification of protein phosphatase interacting proteins from normal and UVA-irradiated HaCaT cell lysates by surface plasmon resonance based binding technique using biotin-microcystin-LR as phosphatase capturing molecule.

    Science.gov (United States)

    Bécsi, Bálint; Dedinszki, Dóra; Gyémánt, Gyöngyi; Máthé, Csaba; Vasas, Gábor; Lontay, Beáta; Erdődi, Ferenc

    2014-09-05

    Identification of the interacting proteins of protein phosphatases is crucial to understand the cellular roles of these enzymes. Microcystin-LR (MC-LR), a potent inhibitor of protein phosphatase-1 (PP1), -2A (PP2A), PP4, PP5 and PP6, was biotinylated, immobilized to streptavidin-coupled sensorchip surface and used in surface plasmon resonance (SPR) based binding experiments to isolate phosphatase binding proteins. Biotin-MC-LR captured PP1 catalytic subunit (PP1c) stably and the biotin-MC-LR-PP1c complex was able to further interact with the regulatory subunit (MYPT1) of myosin phosphatase. Increased biotin-MC-LR coated sensorchip surface in the Surface Prep unit of Biacore 3000 captured PP1c, PP2Ac and their regulatory proteins including MYPT1, MYPT family TIMAP, inhibitor-2 as well as PP2A-A and -Bα-subunits from normal and UVA-irradiated HaCaT cell lysates as revealed by dot blot analysis of the recovered proteins. Biotin-MC-LR was used for the subcellular localization of protein phosphatases in HaCaT cells by identification of phosphatase-bound biotin-MC-LR with fluorescent streptavidin conjugates. Partial colocalization of the biotin-MC-LR signals with those obtained using anti-PP1c and anti-PP2Ac antibodies was apparent as judged by confocal microscopy. Our results imply that biotin-MC-LR is a suitable capture molecule in SPR for isolation of protein phosphatase interacting proteins from cell lysates in sufficient amounts for immunological detection.

  5. Inhibition of Oesophageal Squamous Cell Carcinoma Progression by in vivo Targeting of Hyaluronan Synthesis

    Directory of Open Access Journals (Sweden)

    Savani Rashmin C

    2011-03-01

    Full Text Available Abstract Background Oesophageal cancer is a highly aggressive tumour entity with at present poor prognosis. Therefore, novel treatment options are urgently needed. Hyaluronan (HA is a polysaccharide present in the matrix of human oesophageal squamous cell carcinoma (ESCC. Importantly, in vitro ESCC cells critically depend on HA synthesis to maintain the proliferative phenotype. The aim of the present study is (1 to study HA-synthase (HAS expression and regulation in human ESCC, and (2 to translate the in vitro results into a mouse xenograft model of human ESCC to study the effects of systemic versus tumour targeted HAS inhibition on proliferation and distribution of tumour-bound and stromal hyaluronan. Methods mRNA expression was investigated in human ESCC biopsies by semiquantitative real-time RT PCR. Furthermore, human ESCC were xenografted into NMRI nu/nu mice. The effects on tumour progression and morphology of 4-methylumbelliferone (4-MU, an inhibitor of HA-synthesis, and of lentiviral knock down of HA-synthase 3 (HAS3, the main HAS isoform in the human ESCC tissues and the human ESCC cell line used in this study, were determined. Tumour progression was monitored by calliper measurements and by flat-panel detector volume computed tomography (fpVCT. HA content, cellular composition and proliferation (Ki67 were determined histologically. Results mRNA of HAS isoform 3 (HAS3 was upregulated in human ESCC biopsies and HAS3 mRNA was positively correlated to expression of the epidermal growth factor (EGF receptor. EGF was also proven to be a strong inductor of HAS3 mRNA expression in vitro. During the course of seven weeks, 4-MU inhibited progression of xenograft tumours. Interestingly, remodelling of the tumour into a more differentiated phenotype and inhibition of cell proliferation were observed. Lentiviral knockdown of HAS3 in human ESCC cells prior to xenografting mimicked all effects of 4-MU treatment suggesting that hyaluronan produced by

  6. Hyaluronan-CD44 interaction promotes growth of decidual stromal cells in human first-trimester pregnancy.

    Directory of Open Access Journals (Sweden)

    Rui Zhu

    Full Text Available Hyaluronan (HA and its receptor CD44 are expressed at the maternal-fetal interface, but its role in early pregnancy remains unclear. Here, we found that primary decidual stromal cells (DSCs continuously secreted HA and expressed its receptor CD44. Pregnancy-associated hormones up-regulated HA synthetase (HAS 2 transcription and HA release from DSCs. High molecular weight-HA (HMW-HA, but not medium molecular weight (MMW-HA or low molecular weight (LMW-HA, promoted proliferation and inhibited apoptosis of DSCs in a CD44-dependent manner. The in-cell Western analysis revealed HMW-HA activated PI3K/AKT and mitogen-activated protein kinase (MAPK/ERK1/2 signaling pathways time-dependently. Blocking these pathways by specific inhibitor LY294002 or U0126 abrogated HMW-HA-regulated DSc proliferation and apoptosis. Finally, we have found that HA content, HA molecular weight, HAS2 mRNA level, and CD44 expression were significantly decreased in DSCs from unexplained miscarriage compared with the normal pregnancy. Collectively, our results indicate that higher level and greater molecular mass of HA at maternal-fetal interface contributes to DSc growth and maintenance of DSCs in human early pregnancy.

  7. Tissue hyaluronan expression, as reflected in the sputum of lung cancer patients, is an indicator of malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, M.P.; Sá, V.K. de; Martins, V. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Martins, J.R.M. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Disciplina de Endocrinologia e Metabolismo, Laboratório de Endocrinologia Molecular e Translacional-LEMT, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Parra, E.R. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Mendes, A. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Andrade, P.C. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Reis, R.M. [Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga (Portugal); ICVS/3B' s - PT Government Associate Laboratory, Guimarães (Portugal); Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Longatto-Filho, A. [Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga (Portugal); ICVS/3B' s - PT Government Associate Laboratory, Guimarães (Portugal); Laboratório de Investigação Médica (LIM 14), Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Oliveira, C.Z. [Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Takagaki, T. [Divisão de Pneumologia, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Carraro, D.M. [Centro Internacional de Pesquisa/CIPE, AC Camargo Cancer Center, São Paulo, SP (Brazil); Nader, H.B. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Capelozzi, V.L. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-05-08

    Hyaluronan (HA) shows promise for detecting cancerous change in pleural effusion and urine. However, there is uncertainty about the localization of HA in tumor tissue and its relationship with different histological types and other components of the extracellular matrix, such as angiogenesis. We evaluated the association between HA and degree of malignancy through expression in lung tumor tissue and sputum. Tumoral tissue had significantly increased HA compared to normal tissue. Strong HA staining intensity associated with cancer cells was significant in squamous cell carcinoma compared to adenocarcinoma and large cell carcinoma. A significant direct association was found between tumors with a high percentage of HA and MVD (microvessel density) in tumoral stroma. Similarly significant was the direct association between N1 tumors and high levels of HA in cancer cells. Cox multivariate analysis showed significant association between better survival and low HA. HA increased in sputum from lung cancer patients compared to cancer-free and healthy volunteers and a significant correlation was found between HA in sputum and HA in cancer tissue. Localization of HA in tumor tissue was related to malignancy and reflected in sputum, making this an emerging factor for an important diagnostic procedure in patients suspected to have lung cancer. Further study in additional patients in a randomized prospective trial is required to finalize these results and to validate our quantitative assessment of HA, as well as to couple it to gold standard sputum cytology.

  8. Molecular evolution of the hyaluronan synthase 2 gene in mammals: implications for adaptations to the subterranean niche and cancer resistance.

    Science.gov (United States)

    Faulkes, Christopher G; Davies, Kalina T J; Rossiter, Stephen J; Bennett, Nigel C

    2015-05-01

    The naked mole-rat (NMR) Heterocephalus glaber is a unique and fascinating mammal exhibiting many unusual adaptations to a subterranean lifestyle. The recent discovery of their resistance to cancer and exceptional longevity has opened up new and important avenues of research. Part of this resistance to cancer has been attributed to the fact that NMRs produce a modified form of hyaluronan--a key constituent of the extracellular matrix--that is thought to confer increased elasticity of the skin as an adaptation for living in narrow tunnels. This so-called high molecular mass hyaluronan (HMM-HA) stems from two apparently unique substitutions in the hyaluronan synthase 2 enzyme (HAS2). To test whether other subterranean mammals with similar selection pressures also show molecular adaptation in their HAS2 gene, we sequenced the HAS2 gene for 11 subterranean mammals and closely related species, and combined these with data from 57 other mammals. Comparative screening revealed that one of the two putatively important HAS2 substitutions in the NMR predicted to have a significant effect on hyaluronan synthase function was uniquely shared by all African mole-rats. Interestingly, we also identified multiple other amino acid substitutions in key domains of the HAS2 molecule, although the biological consequences of these for hyaluronan synthesis remain to be determined. Despite these results, we found evidence of strong purifying selection acting on the HAS2 gene across all mammals, and the NMR remains unique in its particular HAS2 sequence. Our results indicate that more work is needed to determine whether the apparent cancer resistance seen in NMR is shared by other members of the African mole-rat clade. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  9. Oleyl-hyaluronan micelles loaded with upconverting nanoparticles for bio-imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pospisilova, Martina, E-mail: martina.pospisilova@contipro.com; Mrazek, Jiri; Matuska, Vit; Kettou, Sofiane; Dusikova, Monika; Svozil, Vit; Nesporova, Kristina; Huerta-Angeles, Gloria; Vagnerova, Hana; Velebny, Vladimir [Contipro Biotech (Czech Republic)

    2015-09-15

    Hyaluronan (HA) represents an interesting polymer for nanoparticle coating due to its biocompatibility and enhanced cell interaction via CD44 receptor. Here, we describe incorporation of oleate-capped β–NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+} nanoparticles (UCNP-OA) into amphiphilic HA by microemulsion method. Resulting structures have a spherical, micelle-like appearance with a hydrodynamic diameter of 180 nm. UCNP-OA-loaded HA micelles show a good stability in PBS buffer and cell culture media. The intensity of green emission of UCNP-OA-loaded HA micelles in water is about five times higher than that of ligand-free UCNP, indicating that amphiphilic HA effectively protects UCNP luminescence from quenching by water molecules. We found that UCNP-OA-loaded HA micelles in concentrations up to 50 μg mL{sup −1} increase cell viability of normal human dermal fibroblasts (NHDF), while viability of human breast adenocarcinoma cells MDA–MB–231 is reduced at these concentrations. The utility of UCNP-OA-loaded HA micelles as a bio-imaging probe was demonstrated in vitro by successful labelling of NHDF and MDA–MB–231 cells overexpressing the CD44 receptor.

  10. Mechanical properties of tyramine substituted-hyaluronan enriched fascia extracellular matrix.

    Science.gov (United States)

    Chin, Likang; Calabro, Anthony; Walker, Esteban; Derwin, Kathleen A

    2012-03-01

    Naturally occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been the topic of recent investigation in the context of rotator cuff tendon repair. We previously reported a method to treat fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) for use as a tendon augmentation scaffold. The presence of crosslinked TS-HA in fascia was associated with an increased macrophage and giant cell response compared to water-treated controls after implantation in a rat abdominal wall model. The objective of this study was to determine the extent to which TS-HA treatment was associated with mechanical property changes of fascia after implantation in the rat model. Fascia samples in all groups demonstrated time-dependent decreases in mechanical properties. TS-HA-treated fascia with crosslinking exhibited a lower toe modulus, a trend toward lower toe stiffness, and a higher transition strain than water-treated controls not only after implantation, but also at time zero. TS-HA treatment, with or without crosslinking, had no significant effect on time-zero or post-implantation load relaxation ratio, load relaxation rate, linear-region stiffness, or linear-region modulus. Our findings demonstrated that the particular TS-HA treatment employed in this study decreased the low-load elastic mechanical properties of fascia ECM, in keeping with the heightened macrophage and giant cell host response seen previously. This work provides a starting point and guidance for investigating alternative HA treatment strategies.

  11. Androgen-stimulated UDP-glucose dehydrogenase expression limits prostate androgen availability without impacting hyaluronan levels

    Science.gov (United States)

    Wei, Qin; Galbenus, Robert; Raza, Ashraf; Cerny, Ronald L.; Simpson, Melanie A.

    2009-01-01

    UDP-glucose dehydrogenase (UGDH) oxidizes UDP-glucose to UDP-glucuronate, an essential precursor for production of hyaluronan (HA), proteoglycans, and xenobiotic glucuronides. High levels of HA turnover in prostate cancer are correlated with aggressive progression. UGDH expression is high in the normal prostate even though HA accumulation is virtually undetectable. Thus, its normal role in the prostate may be to provide precursors for glucuronosyltransferase enzymes, which inactivate and solubilize androgens by glucuronidation. In this report, we quantified androgen dependence of UGDH, glucuronosyltransferase, and HA synthase expression. Androgen dependent and independent human prostate cancer cell lines were used to test the effects of UGDH manipulation on tumor cell growth, HA production and androgen glucuronidation. Dihydrotestosterone (DHT) increased UGDH expression ≈2.5-fold in androgen dependent cells. However, upregulation of UGDH did not affect HA synthase expression or enhance HA production. Mass spectrometric analysis showed that DHT was converted to a glucuronide, DHT-G, at a six-fold higher level in androgen dependent cells relative to androgen independent cells. The increased solubilization and elimination of DHT corresponded to slower cellular growth kinetics, which could be reversed in androgen dependent cells by treatment with a UDP-glucuronate scavenger. Collectively, these results suggest that dysregulated expression of UGDH could promote the development of androgen independent tumor cell growth by increasing available levels of intracellular androgen. PMID:19244115

  12. Rodlike Complexes of a Polyelectrolyte (Hyaluronan) and a Protein (Lysozyme) observed by SANS

    CERN Document Server

    Boué, François; Cousin, Fabrice; Grillo, Isabelle; Morfin, Isabelle; 10.1021/bm100861g

    2012-01-01

    We study by Small Angle Neutron Scattering (SANS) the structure of Hyaluronan -Lysozyme complexes. Hyaluronan (HA) is a polysaccharide of 9 nm intrinsic persistence length that bears one negative charge per disaccharide monomer (Mmol = 401.3 g/mol); two molecular weights, Mw = 6000 and 500 000 Da were used. The pH was adjusted at 4.7 and 7.4 so that lysozyme has a global charge of +10 and + 8 respectively. The lysozyme concentration was varied from 3 to 40 g/L, at constant HA concentration (10 g/L). At low protein concentration, samples are monophasic and SANS experiments reveal only fluctuations of concentration although, at high protein concentration, clusters are observed by SANS in the dense phase of the diphasic samples. In between, close to the onset of the phase separation, a distinct original scattering is observed. It is characteristic of a rod-like shape, which could characterize "single" complexes involving one or a few polymer chains. For the large molecular weight (500 000) the rodlike rigid doma...

  13. Visualization of a hyaluronan network on the surface of silicone-hydrogel materials

    Directory of Open Access Journals (Sweden)

    Wygladacz KA

    2016-07-01

    Full Text Available Katarzyna A Wygladacz, Daniel J Hook Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Abstract: Biotrue multipurpose solution (MPS is a bioinspired disinfecting and conditioning solution that includes hyaluronic acid (HA as a natural wetting agent. Previous studies demonstrated that HA sorbed from Biotrue MPS on both conventional and silicone hydrogel (SiHy contact lens materials; an in vitro simulated-wear test validated the presence of HA on the lens surfaces for as long as 20 hours. In this study, the morphology and distribution of HA sorbed from both Biotrue and pure HA solution on SiHy contact lens surfaces was examined. Atomic force microscopy imaging was used to illustrate the topography of fresh SiHy contact lens materials before and after incubation with 0.1% (w/v HA solution. The distribution, as well as fine details of the HA network, were resolved by first staining HA with Gram’s safranin, then imaging with confocal laser-scanning microscopy and differential interference-contrast microscopy. In this approach, SiHy materials take up the dye (safranin nonspecifically, such that the resultant safranin–HA complex appears dim against the fluorescent lens background. Balafilcon A was chosen as the representative of glassy SiHy lenses that require postpolymerization plasma treatment to increase wettability. Senofilcon A and samfilcon A were chosen as representatives of SiHy materials fabricated with an internal wetting agent. A confluent and dim HA–safranin network was observed adhered to balafilcon A, senofilcon A, and samfilcon A lens surfaces incubated with either 0.1% (w/v HA solution or Biotrue MPS. Therefore, the conditioning function provided by Biotrue MPS may be in part explained by the presence of the HA humectant layer that readily sorbs on the various types of SiHy contact lens materials. Keywords: contact lens, hyaluronan, MPS, AFM, CLSM, DIC microscopy

  14. Improvement and enhancement of antibladder carcinoma cell effects of heteronemin by the nanosized hyaluronan aggregation

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    Huang HH

    2016-03-01

    Full Text Available Han Hsiang Huang,1 Shyh Ming Kuo,2 Yi-Jhen Wu,2 Jui-Hsin Su3 1Department of Veterinary Medicine, National Chiayi University, Chiayi City, 2Department of Biomedical Engineering, I-Shou University, Kaohsiung City, 3National Museum of Marine Biology and Aquarium, Pingtung, Taiwan Abstract: The effects against tumors exerted by marine active compounds have been highlighted and investigated. Polymeric nanoparticles made from biodegradable and biocompatible molecules such as hyaluronan (HA and chitosan (CHI are able to aggregate the compounds to enhance their activities against tumor cells and reduce the toxicity on normal cells. Here, we extensively examined the antitumor activities and the mechanisms of HA/CHI nanoparticles-aggregated heteronemin (HET extracted from the sponge Hippospongia sp. The half-maximal inhibitory concentration (IC50 of pure HET toward T24 bladder carcinoma cells is ~0.28 µg/mL. Pure HET from 0.2 to 0.8 µg/mL and HA nanoparticles-aggregated HET at 0.1 and 0.2 µg/mL significantly reduced T24 cell viability. Compared to pure HET, HA nanoparticles/HET aggregates showed much weaker viability-inhibitory effects on L929 normal fibroblasts. HET dose-dependently suppressed cancer cell migration as HA/CHI nanoparticles-aggregated HET displayed stronger migration-inhibitory effects than pure HET. Flow cytometric analysis showed that pure HET increased early/total apoptosis and JC-1 monomer fluorescence, while HA/CHI nanoparticles-aggregated HET induced higher apoptosis and JC-1 monomer rates than pure HET, suggesting that aggregation of HA nanoparticles offers HET stronger apoptosis-inducing capacity through mitochondrial depolarization. Western blot analysis showed that HA nanoparticles-aggregated HET further increased mitochondrial-associated, caspase-dependent and caspase-independent, as well as endoplasmic reticulum stress-related factors in comparison with pure HET. These data indicated that pure HET possesses cytotoxic

  15. Therapeutic Targeting of Hyaluronan in the Tumor Stroma

    Energy Technology Data Exchange (ETDEWEB)

    Kultti, Anne, E-mail: akultti@halozyme.com [Department of Research, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Li, Xiaoming; Jiang, Ping; Thompson, Curtis B. [Department of Pharmacology and Safety Assessment, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Frost, Gregory I. [Department of General and Administrative, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Shepard, H. Michael [Department of Research, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States)

    2012-09-06

    The tumor stroma, consisting of non-malignant cells and the extracellular matrix, undergoes significant quantitative and qualitative changes throughout malignant transformation and tumor progression. With increasing recognition of the role of the tumor microenvironment in disease progression, stromal components of the tumor have become attractive targets for therapeutic intervention. Stromal accumulation of the glycosaminoglycan hyaluronan occurs in many tumor types and is frequently associated with a negative disease prognosis. Hyaluronan interacts with other extracellular molecules as well as cellular receptors to form a complex interaction network influencing physicochemical properties, signal transduction, and biological behavior of cancer cells. In preclinical animal models, enzymatic removal of hyaluronan is associated with remodeling of the tumor stroma, reduction of tumor interstitial fluid pressure, expansion of tumor blood vessels and facilitated delivery of chemotherapy. This leads to inhibition of tumor growth and increased survival. Current evidence shows that abnormal accumulation of hyaluronan may be an important stromal target for cancer therapy. In this review we highlight the role of hyaluronan and hyaluronan-mediated interactions in cancer, and discuss historical and recent data on hyaluronidase-based therapies and the effect of hyaluronan removal on tumor growth.

  16. Hyaluronan - a functional and structural sweet spot in the tissue microenvironment

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    James eMonslow

    2015-05-01

    Full Text Available Transition from homeostatic to reactive matrix remodeling is a fundamental adaptive tissue response to injury, inflammatory disease, fibrosis and cancer. Alterations in architecture, physical properties and matrix composition result in changes in biomechanical and biochemical cellular signaling. The dynamics of pericellular and extracellular matrices, including matrix protein, proteoglycan and glycosaminoglycan modification are continually emerging as essential regulatory mechanisms underlying cellular and tissue function. Nevertheless, the impact of matrix organization on inflammation and immunity in particular, and the consequent effects on tissue healing and disease outcome are arguably under-studied aspects of adaptive stress responses. Herein, we review how the predominant glycosaminoglycan hyaluronan (HA contributes to the structure and function of the tissue microenvironment. Specifically, we examine the evidence of HA degradation and the generation of biologically-active smaller HA fragments in pathological settings in vivo. We discuss how HA fragments versus nascent HA via alternate receptor-mediated signaling influence inflammatory cell recruitment and differentiation, resident cell activation, as well as tumor growth, survival and metastasis. Finally, we discuss how HA fragmentation impacts restoration of normal tissue function and pathological outcomes in disease.

  17. Computational Study of Nanosized Drug Delivery from Cyclodextrins, Crown Ethers and Hyaluronan in Pharmaceutical Formulations.

    Science.gov (United States)

    Torrens, Francisco; Castellano, Gloria

    2015-01-01

    The problem in this work is the computational characterization of cyclodextrins, crown ethers and hyaluronan (HA) as hosts of inclusion complexes for nanosized drug delivery vehicles in pharmaceutical formulations. The difficulty is addressed through a computational study of some thermodynamic, geometric and topological properties of the hosts. The calculated properties of oligosaccharides of D-glucopyranoses allow these to act as co-solvents of polyanions in water. In crown ethers, the central channel is computed. Mucoadhesive polymer HA in formulations releases drugs in mucosas. Geometric, topological and fractal analyses are carried out with code TOPO. Reference calculations are performed with code GEPOL. From HA to HA·3Ca and hydrate, the hydrophilic solvent-accessible surface varies with the count of H-bonds. The fractal dimension rises. The dimension of external atoms rises resulting 1.725 for HA. It rises going to HA·3Ca and hydrate. Nonburied minus molecular dimension rises and decays. Hydrate globularity is lower than O(water), Ca(2+) and O(HA). Ca(2+) rugosity is smaller than for hydrate, O(HA) and O(water). Ca(2+) and O(water) accessibilities are greater than hydrate. Conclusions are drawn on: (1) the relative stability of linear/cyclic and shorter/larger polymers; (2) the atomic analysis of properties allows determining the atoms with maximum reactivity.

  18. Anticancer Effects of Sinulariolide-Conjugated Hyaluronan Nanoparticles on Lung Adenocarcinoma Cells

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    Kuan Yin Hsiao

    2016-03-01

    Full Text Available Lung cancer is one of the most clinically challenging malignant diseases worldwide. Sinulariolide (SNL, extracted from the farmed coral species Sinularia flexibilis, has been used for suppressing malignant cells. For developing anticancer therapeutic agents, we aimed to find an alternative for non-small cell lung cancer treatment by using SNL as the target drug. We investigated the SNL bioactivity on A549 lung cancer cells by conjugating SNL with hyaluronan nanoparticles to form HA/SNL aggregates by using a high-voltage electrostatic field system. SNL was toxic on A549 cells with an IC50 of 75 µg/mL. The anticancer effects of HA/SNL aggregates were assessed through cell viability assay, apoptosis assays, cell cycle analyses, and western blotting. The size of HA/SNL aggregates was approximately 33–77 nm in diameter with a thin continuous layer after aggregating numerous HA nanoparticles. Flow cytometric analysis revealed that the HA/SNL aggregate-induced apoptosis was more effective at a lower SNL dose of 25 µg/mL than pure SNL. Western blotting indicated that caspases-3, -8, and -9 and Bcl-xL and Bax played crucial roles in the apoptotic signal transduction pathway. In summary, HA/SNL aggregates exerted stronger anticancer effects on A549 cells than did pure SNL via mitochondria-related pathways.

  19. Mechanically strong triple network hydrogels based on hyaluronan and poly(N,N-dimethylacrylamide).

    Science.gov (United States)

    Tavsanli, Burak; Can, Volkan; Okay, Oguz

    2015-11-21

    Hyaluronan (HA) is a natural polyelectrolyte with distinctive biological functions. Cross-linking of HA to generate less degradable hydrogels for use in biomedical applications has attracted interest over many years. One limitation of HA hydrogels is that they are very brittle and/or easily dissolve in physiological environments, which limit their use in load-bearing applications. Herein, we describe the preparation of triple-network (TN) hydrogels based on HA and poly(N,N-dimethylacrylamide) (PDMA) of high mechanical strength by sequential gelation reactions. TN hydrogels containing 81-91% water sustain compressive stresses above 20 MPa and exhibit Young's moduli of up to 1 MPa. HA of various degrees of methacrylation was used as a multifunctional macromer for the synthesis of the brittle first-network component, while loosely cross-linked PDMA was used as the ductile, second and third network components of TN hydrogels. By tuning the methacrylation degree of HA, double-network hydrogels with a fracture stress above 10 MPa and a fracture strain of 96% were obtained. Increasing the ratio of ductile-to-brittle components via the TN approach further increases the fracture stress above 20 MPa. Cyclic mechanical tests show that, although TN hydrogels internally fracture even under small strain, the ductile components hinder macroscopic crack propagation by keeping the macroscopic gel samples together.

  20. Oxidized low density lipoprotein (LDL) affects hyaluronan synthesis in human aortic smooth muscle cells.

    Science.gov (United States)

    Viola, Manuela; Bartolini, Barbara; Vigetti, Davide; Karousou, Evgenia; Moretto, Paola; Deleonibus, Sara; Sawamura, Tatsuya; Wight, Thomas N; Hascall, Vincent C; De Luca, Giancarlo; Passi, Alberto

    2013-10-11

    Thickening of the vessel in response to high low density lipoprotein(s) (LDL) levels is a hallmark of atherosclerosis, characterized by increased hyaluronan (HA) deposition in the neointima. Human native LDL trapped within the arterial wall undergoes modifications such as oxidation (oxLDL). The aim of our study is to elucidate the link between internalization of oxLDL and HA production in vitro, using human aortic smooth muscle cells. LDL were used at an effective protein concentration of 20-50 μg/ml, which allowed 80% cell viability. HA content in the medium of untreated cells was 28.9 ± 3.7 nmol HA-disaccharide/cell and increased after oxLDL treatment to 53.9 ± 5.6. OxLDL treatments doubled the transcripts of HA synthase HAS2 and HAS3. Accumulated HA stimulated migration of aortic smooth muscle cells and monocyte adhesiveness to extracellular matrix. The effects induced by oxLDL were inhibited by blocking LOX-1 scavenger receptor with a specific antibody (10 μg/ml). The cholesterol moiety of LDL has an important role in HA accumulation because cholesterol-free oxLDL failed to induce HA synthesis. Nevertheless, cholesterol-free oxLDL and unmodified cholesterol (20 μg/ml) induce only HAS3 transcription, whereas 22,oxysterol affects both HAS2 and HAS3. Moreover, HA deposition was associated with higher expression of endoplasmic reticulum stress markers (CHOP and GRP78). Our data suggest that HA synthesis can be induced in response to specific oxidized sterol-related species delivered through oxLDL.

  1. Effect of Hyaluronan on Developmental Competence and Quality of Oocytes and Obtained Blastocysts from In Vitro Maturation of Bovine Oocytes

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    Jolanta Opiela

    2014-01-01

    Full Text Available The objective of the present study was to evaluate the effect of hyaluronan (HA during IVM on meiotic maturation, embryonic development, and the quality of oocytes, granulosa cells (GC, and obtained blastocysts. COCs were matured in vitro in control medium and medium with additional 0.035% or 0.07% of exogenous HA. The meiotic maturity did not differ between the analysed groups. The best rate and the highest quality of obtained blastocysts were observed when 0.07% HA was used. A highly significant difference (P<0.001 was noted in the mean number of apoptotic nuclei per blastocyst and in the DCI between the 0.07% HA and the control blastocysts (P<0.01. Our results suggest that addition of 0.035% HA and 0.07% HA to oocyte maturation media does not affect oocyte nuclear maturation and DNA fragmentation. However, the addition of 0.07% HA during IVM decreases the level of blastocysts DNA fragmentation. Finally, our results suggest that it may be risky to increase the HA concentration during IVM above 0.07% as we found significantly higher Bax mRNA expression levels in GC cultured with 0.07% HA. The final concentration of HA being supplemented to oocyte maturation media is critical for the success of the IVP procedure.

  2. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy

    Directory of Open Access Journals (Sweden)

    Yang R

    2016-12-01

    Full Text Available Rui-Meng Yang,1,* Chao-Ping Fu,2,* Jin-Zhi Fang,1 Xiang-Dong Xu,1 Xin-Hua Wei,1 Wen-Jie Tang,1 Xin-Qing Jiang,1 Li-Ming Zhang2 1Department of Radiology, Guangzhou First People’s Hospital, Guangzhou Medical University, 2School of Materials Science and Engineering, School of Chemistry, Sun Yat-sen University, Guangzhou, China *These authors contributed equally to this work Abstract: Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs, which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhancement on T2-weighted magnetic resonance imaging and photothermal effect targeted CD44 HA receptor-overexpressing breast cancer. All these results indicated that HA-SPIONs have great potential for effective diagnosis and treatment of cancer. Keywords: iron oxide nanoparticles, surface functionalization, bioactive glycosaminoglycan, magnetic resonance imaging, cellular uptake, breast carcinoma

  3. Hyaluronan-Based Therapy for Metastatic Prostate Cancer

    Science.gov (United States)

    2015-07-01

    interplay between the extrinsic and intrinsic apoptotic pathways would be an effective rationale for cancer therapy . In reality , however, dulanermin...AWARD NUMBER: W81XWH-14-1-0184 TITLE: Hyaluronan-Based Therapy for Metastatic Prostate Cancer PRINCIPAL INVESTIGATOR: Dr. Magdelena...5a. CONTRACT NUMBER W81XWH-14-1-0184 Hyaluronan-Based Therapy for Metastatic Prostate Cancer 5b. GRANT NUMBER W81XWH-14-1-0184 5c. PROGRAM

  4. Hyaluronan Benzyl Ester as a Scaffold for Tissue Engineering

    OpenAIRE

    2009-01-01

    Tissue engineering is a multidisciplinary field focused on in vitro reconstruction of mammalian tissues. In order to allow a similar three-dimensional organization of in vitro cultured cells, biocompatible scaffolds are needed. This need has provided immense momentum for research on “smart scaffolds” for use in cell culture. One of the most promising materials for tissue engineering and regenerative medicine is a hyaluronan derivative: a benzyl ester of hyaluronan (HYAFF®). HYAFF® can be proc...

  5. Two fluoroquinolones and their combinations with hyaluronan: comparison of effects on canine chondrocyte culture.

    Science.gov (United States)

    Siengdee, P; Euppayo, T; Buddhachat, K; Chomdej, S; Nganvongpanit, K

    2016-10-01

    Fluoroquinolones (FQs) are frequently used for septic arthritis. Increased antibacterial activity has been associated with mammalian cell cytotoxicity that may increase the risk of developing osteoarthritis. This study compared the direct effects of two different FQs, enrofloxacin (Enro) and marbofloxacin (Mar), on normal primary canine chondrocytes and inflammatory-stimulated chondrocytes, in addition to their administration in combination with hyaluronan (HA). Cell viability, cell apoptosis, s-GAG production, and expression patterns of inflammatory, extracellular matrix (ECM) component and protease genes were measured. Enro co-culturing with HA could modify s-GAG synthesis compared with the negative control group. Co-treatment with both FQs and HA significantly decreased cell viability and induced more total apoptotic cell death compared with the negative control and pre-IL-1β-stimulated group. Enro regulated IL-1β-stimulated cells to overexpress IL-1β, TNF, and MMP3, whereas Mar induced upregulation of PTGS2 and NFKB1 and enhanced the expression of ECM component genes HAS1, COL2A1, and ACAN as well as TIMP1 and MMP9. Simultaneous use of HA with Enro can effectively reduce the expression of IL-1β, TNF, and MMP3 in pre-IL-1β-stimulated chondrocytes. These results suggest the beneficial effects of HA in reducing the adverse effects of Enro treatment at the transcriptional level. © 2016 John Wiley & Sons Ltd.

  6. Normal and shear interactions between hyaluronan-aggrecan complexes mimicking possible boundary lubricants in articular cartilage in synovial joints.

    Science.gov (United States)

    Seror, Jasmine; Merkher, Yulia; Kampf, Nir; Collinson, Lisa; Day, Anthony J; Maroudas, Alice; Klein, Jacob

    2012-11-12

    Using a surface force balance, normal and shear interactions have been measured between two atomically smooth surfaces coated with hyaluronan (HA), and with HA/aggrecan (Agg) complexes stabilized by cartilage link protein (LP). Such HA/Agg/LP complexes are the most abundant mobile macromolecular species permeating articular cartilage in synovial joints and have been conjectured to be present as boundary lubricants at its surface. The aim of the present study is to gain insight into the extremely efficient lubrication when two cartilage surfaces slide past each other in healthy joints, and in particular to elucidate the possible role in this of the HA/Agg/LP complexes. Within the range of our parameters, our results reveal that the HA/Agg/LP macromolecular surface complexes are much better boundary lubricants than HA alone, likely because of the higher level of hydration, due to the higher charge density, of the HA/Agg/LP layers with respect to the HA alone. However, the friction coefficients (μ) associated with the mutual interactions and sliding of opposing HA/Agg/LP layers (μ ≈ 0.01 up to pressure P of ca. 12 atm, increasing sharply at higher P) suggest that such complexes by themselves cannot account for the remarkable boundary lubrication observed in mammalian joints (up to P > 50 atm).

  7. Mishima jo ha kyu

    Directory of Open Access Journals (Sweden)

    Matteo Casari

    2012-01-01

    Full Text Available Abstract – IT La grandezza artistica di Mishima si è espressa attraverso una eterogenea gamma di linguaggi tra i quali il teatro – nella drammaturgia ma anche nella saggistica, regia, recitazione e direzione di compagnia – ha avuto un ruolo di primo piano. Al pari di un uomo di scena Mishima inaugura, a partire dagli anni ’50, un processo di attenzione al proprio corpo come possibile, anzi necessario, veicolo di estrinsecazione etico-estetica tanto da poter istituire l’equazione corpo-teatro quale snodo profondo del suo processo creativo. Il corpo sognato e ottenuto da Mishima attraverso l’addestramento nel kendo, in altre arti marziali e nel body building si conformava ad un ideale estetico di matrice greco-classica assai lontano dal corpo teatrale nipponico. Il corpo come luogo di elaborazione e strumento di espressione autentica da realizzare con impegno, però, lo legano profondamente alle esperienze nascenti – tra gli anni ’50 e ’60 – delle avanguardie teatrali giapponesi. La metafora teatrale è spesso usata nella lettura critica del Mishima uomo e artista con accezione deteriore: un personaggio che dà spettacolo di sé con ripetute provocazioni tra le quali il suicidio del 25 novembre 1970 non sarebbe che l’esempio ultimo e più estremo. La costruzione di sé come personaggio, invece, sembrerebbe corrispondere ad una ben più profonda e meditata necessità di comporre la propria vita in una sapiente messa in scena di classica perfezione: i principi della scansione ritmico formale del jo ha kyu, pilastro teorico del teatro no codificato da Zeami tra XIV e XV secolo, offrono un valido modello di riferimento. Abstract – EN Mishima’s artistic greatness has been expressed through a diverse range of languages among wich theater – in dramaturgy as well as in written essays, as a director, performer and in company direction – played a central role. As a true front-man, Mishima – starting from the 50’s

  8. Hyaluronan-lecithin foils and their properties

    Energy Technology Data Exchange (ETDEWEB)

    BiaIopiotrowicz, Tomasz [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Janczuk, BronisIaw [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Fiedorowicz, Maciej [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Khachatryan, Gohar [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Tomasik, Piotr [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland)]. E-mail: rrtomasi@cyf-kr.edu.pl; Bakos, Dusan [Faculty of Chemical and Food Technology, Slovak Technical University, Radlinskeho 9, 812 37 Bratislava (Slovakia)

    2006-01-10

    Thin, elastic foils of good resistance to the air exposure, patented as wound healing aids, were prepared by evaporation of a blend of lecithin (L) and sodium hyaluronan (H) taken under varying proportions. The contact angle for water, glycerol, formamide, ethylene glycol and diiodomethane, was determined for these foils. The contact angle was correlated against the H:L foil composition. For all liquids but formamide the highest contact angle was noted for the H:L = 2:1 (g g{sup -1}) ratio. The contact angles provided estimation of the work of adhesion. At the same L:H ratio the work of adhesion was the lowest. It was suggested that lecithin cross-linked hyaluronan. Since the work of adhesion of the studied liquids was similar to that of diiodomethane, it could be concluded that almost all functional groups on the foil surface were completely blocked. Perhaps, at H:L = 2:1 (g g{sup -1}) a stoichiometric complex of hyaluronic acid with lecithin was formed, and polar functional groups from both reagents were involved. Foils seem to be electrostatic complexes of H with L. Foils with the H:L equal to 2:1 exhibited specific properties confirmed by the IR reflectance spectra of the foils. The thermogravimetry (TG/DTG) also revealed unique thermal behaviour confirming other specific properties of the foil of this composition. For the same ratio a thorough inspection of the scanning electron micrographs (SEM) revealed few irregularly distributed perforations of 1-2 {mu}m in diameter seen as black points, which can be recognized as pores. Properties of the foils determined in the contact angle measurements are nicely backed by the results from thermogravimetric and scanning electron microscopic studies.

  9. Intermonomer Interactions in Hemagglutinin Subunits HA1 and HA2 Affecting Hemagglutinin Stability and Influenza Virus Infectivity

    Science.gov (United States)

    DeFeo, Christopher J.; Alvarado-Facundo, Esmeralda; Vassell, Russell

    2015-01-01

    ABSTRACT Influenza virus hemagglutinin (HA) mediates virus entry by binding to cell surface receptors and fusing the viral and endosomal membranes following uptake by endocytosis. The acidic environment of endosomes triggers a large-scale conformational change in the transmembrane subunit of HA (HA2) involving a loop (B loop)-to-helix transition, which releases the fusion peptide at the HA2 N terminus from an interior pocket within the HA trimer. Subsequent insertion of the fusion peptide into the endosomal membrane initiates fusion. The acid stability of HA is influenced by residues in the fusion peptide, fusion peptide pocket, coiled-coil regions of HA2, and interactions between the surface (HA1) and HA2 subunits, but details are not fully understood and vary among strains. Current evidence suggests that the HA from the circulating pandemic 2009 H1N1 influenza A virus [A(H1N1)pdm09] is less stable than the HAs from other seasonal influenza virus strains. Here we show that residue 205 in HA1 and residue 399 in the B loop of HA2 (residue 72, HA2 numbering) in different monomers of the trimeric A(H1N1)pdm09 HA are involved in functionally important intermolecular interactions and that a conserved histidine in this pair helps regulate HA stability. An arginine-lysine pair at this location destabilizes HA at acidic pH and mediates fusion at a higher pH, while a glutamate-lysine pair enhances HA stability and requires a lower pH to induce fusion. Our findings identify key residues in HA1 and HA2 that interact to help regulate H1N1 HA stability and virus infectivity. IMPORTANCE Influenza virus hemagglutinin (HA) is the principal antigen in inactivated influenza vaccines and the target of protective antibodies. However, the influenza A virus HA is highly variable, necessitating frequent vaccine changes to match circulating strains. Sequence changes in HA affect not only antigenicity but also HA stability, which has important implications for vaccine production, as well

  10. Antioxidant protects against increases in low molecular weight hyaluronan and inflammation in asphyxiated newborn pigs resuscitated with 100% oxygen.

    Directory of Open Access Journals (Sweden)

    Helene C D Østerholt

    Full Text Available BACKGROUND: Newborn resuscitation with 100% oxygen is associated with oxidative-nitrative stresses and inflammation. The mechanisms are unclear. Hyaluronan (HA is fragmented to low molecular weight (LMW by oxidative-nitrative stresses and can promote inflammation. We examined the effects of 100% oxygen resuscitation and treatment with the antioxidant, N-acetylcysteine (NAC, on lung 3-nitrotyrosine (3-NT, LMW HA, inflammation, TNFα and IL1ß in a newborn pig model of resuscitation. METHODS & PRINCIPAL FINDINGS: Newborn pigs (n = 40 were subjected to severe asphyxia, followed by 30 min ventilation with either 21% or 100% oxygen, and were observed for the subsequent 150 minutes in 21% oxygen. One 100% oxygen group was treated with NAC. Serum, bronchoalveolar lavage (BAL, lung sections, and lung tissue were obtained. Asphyxia resulted in profound hypoxia, hypercarbia and metabolic acidosis. In controls, HA staining was in airway subepithelial matrix and no 3-NT staining was seen. At the end of asphyxia, lavage HA decreased, whereas serum HA increased. At 150 minutes after resuscitation, exposure to 100% oxygen was associated with significantly higher BAL HA, increased 3NT staining, and increased fragmentation of lung HA. Lung neutrophil and macrophage contents, and serum TNFα and IL1ß were higher in animals with LMW than those with HMW HA in the lung. Treatment of 100% oxygen animals with NAC blocked nitrative stress, preserved HMW HA, and decreased inflammation. In vitro, peroxynitrite was able to fragment HA, and macrophages stimulated with LMW HA increased TNFα and IL1ß expression. CONCLUSIONS & SIGNIFICANCE: Compared to 21%, resuscitation with 100% oxygen resulted in increased peroxynitrite, fragmentation of HA, inflammation, as well as TNFα and IL1ß expression. Antioxidant treatment prevented the expression of peroxynitrite, the degradation of HA, and also blocked increases in inflammation and inflammatory cytokines. These findings

  11. Green synthesis, characterization, and anticancer activity of hyaluronan/zinc oxide nanocomposite.

    Science.gov (United States)

    Namvar, Farideh; Azizi, Susan; Rahman, Heshu Sulaiman; Mohamad, Rosfarizan; Rasedee, Abdullah; Soltani, Mozhgan; Rahim, Raha Abdul

    2016-01-01

    The study describes an in situ green biosynthesis of zinc oxide nanocomposite using the seaweed Sargassum muticum water extract and hyaluronan biopolymer. The morphology and optical properties of the hyaluronan/zinc oxide (HA/ZnO) nanocomposite were determined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet-vis analysis. Electron microscopy and X-ray diffraction analysis showed that the zinc oxide nanoparticles were polydispersed with a mean size of 10.2±1.5 nm. The nanoparticles were mostly hexagonal in crystalline form. The HA/ZnO nanocomposite showed the absorption properties in the ultraviolet zone that is ascribed to the band gap of zinc oxide nanocomposite. In the cytotoxicity study, cancer cells, pancreatic adenocarcinoma (PANC-1), ovarian adenocarcinoma (CaOV-3), colonic adenocarcinoma (COLO205), and acute promyelocytic leukemia (HL-60) cells were treated with HA/ZnO nanocomposite. At 72 hours of treatment, the half maximal inhibitory concentration (IC50) value via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was 10.8±0.3 μg/mL, 15.4±1.2 μg/mL, 12.1±0.9 μg/mL, and 6.25±0.5 μg/mL for the PANC-1, CaOV-3, COLO-205, and HL-60 cells, respectively, showing that the composite is most toxic to the HL-60 cells. On the other hand, HA/ZnO nanocomposite treatment for 72 hours did not cause toxicity to the normal human lung fibroblast (MRC-5) cell line. Using fluorescent dyes and flow cytometry analysis, HA/ZnO nanocomposite caused G2/M cell cycle arrest and stimulated apoptosis-related increase in caspase-3 and -7 activities of the HL-60 cells. Thus, the study shows that the HA/ZnO nanocomposite produced through green synthesis has great potential to be developed into an efficacious therapeutic agent for cancers.

  12. Hyaluronan/Tween 80-assisted synthesis of silver nanoparticles for biological application

    Science.gov (United States)

    Li, Hui-Jun; Zhang, An-Qi; Sui, Li; Qian, Dong-Jin; Chen, Meng

    2015-02-01

    Water-soluble and well-stabilized silver nanoparticles (NPs) of small size have been synthesized using hyaluronan (HA) and Tween 80 as reducing and stabilizing agents. The effect of reaction conditions on the formation process of silver NPs was studied, and an aggregative growth mechanism of the silver NPs dominated in HA/Tween 80 system at pH 12 has been proposed. The obtained Ag NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Moreover, the stability of the HA-Tween 80-silver NPs in normal saline was also studied, and a flexible blend membrane containing chitosan, gelatin, and the HA-Tween 80-silver NPs was prepared for further biological applications. Due to the high specific surface area and improved stability of silver NPs, the chitosan-gelatin-silver membrane has shown high antibacterial activity for strains of Escherichia coli. The cell viability tests indicate that the polymer membrane is non-cytotoxic to HepG2 cells, which might be attributed to its good biocompatibility.

  13. Characterization of and host response to tyramine substituted-hyaluronan enriched fascia extracellular matrix

    Science.gov (United States)

    Chin, LiKang; Calabro, Anthony; Rodriguez, E. Rene; Tan, Carmela D.; Walker, Esteban

    2011-01-01

    Naturally-occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been previously investigated for soft tissue repair. We propose to enrich fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) to modulate inflammation associated with implantation and enhance fibroblast infiltration. As critical determinants of constructive remodeling, the host inflammatory response and macrophage polarization to TS-HA enriched fascia were characterized in a rat abdominal wall model. TS-HA treated fascia with cross-linking had a similar lymphocyte (P = 0.11) and plasma cell (P = 0.13) densities, greater macrophage (P = 0.001) and giant cell (P fascia, with or without cross-linking, exhibited a predominantly M2 pro-remodeling macrophage profile similar to water controls (P = 0.82), which is suggestive of constructive tissue remodeling. Our findings demonstrated that HA augmentation can alter the host response to an ECM, but the appropriate concentration and molecular weight needed to minimize chronic inflammation within the scaffold remains to be determined. PMID:21553156

  14. Therapeutic Effect on Targeted Hyaluronan Binding Peptide on Neurofibromatosis

    Science.gov (United States)

    2005-09-01

    Furthermore, it confers stability to the peptide at low pH and high temperature, which makes it easy to manipulate and gives it a long shelf - life . Due to...were incubated with peptides for 24 hours and the cells were washed and harvested in lysis buffer (10 mM potassium phosphate at pH 7.5, 1 mM EDTA, 5...30 min followed by incubation with FITC-conjugated anti-goat IgG (1:200) at 4 ºC for 30 min. The cells were finally stained with propidium iodide and

  15. Targeting of Prostate Cancer with Hyaluronan-Binding Proteins

    Science.gov (United States)

    2005-06-01

    library of a human sarcoma cell line derived from chondrocytes as template. The cDNAs cording for the portion of aggrecan (993 bp) and the full-length...20. Okunieff P, Li M, Liu W, Sun J, Fenton B, Zhang L, Ding I.: Keratinocyte growth factors radioprotect bowel and bone marrow but not KHT sarcoma ...Triptolide Nanoparticle Aims: 1) To examine the effects of RGD/NGR-PA-TPL- lipo on primary and metastatic breast cancer; and 2) To examine the targeting of

  16. Peritoneal Adhesion and Angiogenesis in Ovarian Carcinoma Are Inversely Regulated by Hyaluronan: The Role of Gonadotropins

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    Yael Chagit Tzuman

    2010-01-01

    Full Text Available Ovarian carcinoma is the leading cause of death among gynecologic cancers. Although transformation of the outer ovarian epithelium was linked with ovulation, the disease is significantly more prevalent and severe in postmenopausal women. We postulated that menopause could augment ovarian cancer progression through the effects of gonadotropins on multifocal seeding to the mesothelial layer lining the peritoneum. This seeding is mediated by integrins as well as by CD44 interaction with hyaluronan (HA. Here, we report the effect of gonadotropins on HA synthesis and degradation and on peritoneal adhesion. A significant concentration- and time-dependent induction in expression levels of HA synthases (HASs and hyaluronidases (Hyals was observed in vitro on stimulation of human epithelial ovarian carcinoma cells by gonadotropins. Hormonal regulation of HA-mediated adhesion was manifested in vivo as well, by fluorescence microscopy of stained MLS multicellular tumor spheroids. The number of spheroids adhered to the mesothelium of ovariectomized CD-1 nude mice 9.5 hours after intraperitoneal insertion was significantly higher than in nonovariectomized mice. Inhibition of HA synthesis by 6-diazo-5-oxo-1-norleucine (DON both in spheroids and ovariectomized mice significantly reduced the number of adhered spheroids. Thus, the change in the hormonal environment during menopause assists in HA-dependent adherence of ovarian cancer spheroids onto the peritoneum. However, HA is antiangiogenic and it can significantly suppress tumor progression. Accordingly, angiogenesis of the adhered spheroids was significantly elevated in DON-treated tumors. These results can explain the selective pressure that can lead to simultaneously increased tumor expression of both HASs and Hyals.

  17. Mechanical Properties of Tyramine Substituted-Hyaluronan Enriched Fascia Extracellular Matrix

    Science.gov (United States)

    Chin, LiKang; Calabro, Anthony; Walker, Esteban; Derwin, Kathleen A.

    2011-01-01

    Naturally-occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been the topic of recent investigation in the context of rotator cuff tendon repair. We previously reported a method to treat fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) for use as a tendon augmentation scaffold. The presence of cross-linked TS-HA in fascia was associated with an increased macrophage and giant cell response compared to water treated controls after implantation in a rat abdominal wall model. The objective of this study was to determine the extent to which TS-HA treatment was associated with mechanical property changes of fascia after implantation in the rat model. Fascia samples in all groups demonstrated time-dependent decreases in mechanical properties. TS-HA treated fascia with cross-linking exhibited a lower toe modulus, a trend toward lower toe stiffness, and a higher transition strain than water treated controls not only after implantation, but also at time zero. TS-HA treatment, with or without cross-linking, had no significant effect on time-zero or post-implantation load relaxation ratio, load relaxation rate, linear-region stiffness, or linear-region modulus. Our findings demonstrated that the particular TS-HA treatment employed in this study decreased the low-load elastic mechanical properties of fascia ECM, in keeping with the heightened macrophage and giant cell host response seen previously. This work provides a starting point and guidance for investigating alternative HA treatment strategies. PMID:22238019

  18. Hyaluronan and RHAMM in Wound Repair and the “Cancerization” of Stromal Tissues

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    Cornelia Tolg

    2014-01-01

    Full Text Available Tumors and wounds share many similarities including loss of tissue architecture, cell polarity and cell differentiation, aberrant extracellular matrix (ECM remodeling (Ballard et al., 2006 increased inflammation, angiogenesis, and elevated cell migration and proliferation. Whereas these changes are transient in repairing wounds, tumors do not regain tissue architecture but rather their continued progression is fueled in part by loss of normal tissue structure. As a result tumors are often described as wounds that do not heal. The ECM component hyaluronan (HA and its receptor RHAMM have both been implicated in wound repair and tumor progression. This review highlights the similarities and differences in their roles during these processes and proposes that RHAMM-regulated wound repair functions may contribute to “cancerization” of the tumor microenvironment.

  19. Pulmonary surfactant adsorption is increased by hyaluronan or polyethylene glycol.

    Science.gov (United States)

    Taeusch, H William; Dybbro, Eric; Lu, Karen W

    2008-04-01

    In acute lung injuries, inactivating agents may interfere with transfer (adsorption) of pulmonary surfactants to the interface between air and the aqueous layer that coats the interior of alveoli. Some ionic and nonionic polymers reduce surfactant inactivation in vitro and in vivo. In this study, we tested directly whether an ionic polymer, hyaluronan, or a nonionic polymer, polyethylene glycol, enhanced adsorption of a surfactant used clinically. We used three different methods of measuring adsorption in vitro: a modified pulsating bubble surfactometer; a King/Clements device; and a spreading trough. In addition we measured the effects of both polymers on surfactant turbidity, using this assay as a nonspecific index of aggregation. We found that both hyaluronan and polyethylene glycol significantly increased the rate and degree of surfactant material adsorbed to the surface in all three assays. Hyaluronan was effective in lower concentrations (20-fold) than polyethylene glycol and, unlike polyethylene glycol, hyaluronan did not increase apparent aggregation of surfactant. Surfactant adsorption in the presence of serum was also enhanced by both polymers regardless of whether hyaluronan or polyethylene glycol was included with serum in the subphase or added to the surfactant applied to the surface. Therefore, endogenous polymers in the alveolar subphase, or exogenous polymers added to surfactant used as therapy, may both be important for reducing inactivation of surfactant that occurs with various lung injuries.

  20. Influence of Heating on the Structure of Hyaluronan

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Hyaluronan may be used in tissue engineering as a scaffold, and since the scaffold should degrade after the cells have proliiferated, and heat treatment is a method to achieve low molecular weight material.In this essay, we developed a new method to choose the characteristic heat treatment temperature, and applied a simple method to prepare the hyaluronan scaffold. We have acquired the TG and DTA curves of hyaluronan by thermal analysis, according to which we selected 310 ℃ ,375 ℃ and 500 ℃ as the heat treatment points. After heat treatment, test the infrared spectrum of the powder respectively. In conclusion, the scaffold formed by lyophilization exhibits a porous structure, and the occurrence of new groups after heating assumes the change of the molecular chain.

  1. Design of benzimidazole- and benzoxazole-2-thione derivatives as inhibitors of bacterial hyaluronan lyase.

    Science.gov (United States)

    Braun, Stephan; Botzki, Alexander; Salmen, Sunnhild; Textor, Christian; Bernhardt, Günther; Dove, Stefan; Buschauer, Armin

    2011-09-01

    Bacterial hyaluronan lyases (Hyal) degrade hyaluronan, an important component of the extracellular matrix, and are involved in microbial spread. Hyal inhibitors may serve as tools to study the role of the enzyme, its substrates and products in the course of bacterial infections. Moreover, such enzyme inhibitors are potential candidates for antibacterial combination therapy. Based on crystal structures of Streptococcus pneumoniae Hyal in complex with a hexasaccharide substrate and with different inhibitors, 1-acylated benzimidazole-2-thiones and benzoxazole-2-thiones were derived as new leads for the inhibition of Streptococcus agalactiae strain 4755 Hyal. Structure-based optimization led to N-(3-phenylpropionyl)benzoxazole-2-thione, one of the most potent compounds known to date (IC(50) values: 24 μM at pH 7.4, 15 μM at pH 5). Among the 27 new derivatives, other N-acylated benzimidazoles and benzoxazoles are just as active at pH 7.4, but not at pH 5. The results support a binding mode characterized by interactions with residues in the catalytic site and with a hydrophobic patch.

  2. Pathophysiology of the Peritoneal Membrane during Peritoneal Dialysis: The Role of Hyaluronan

    Directory of Open Access Journals (Sweden)

    Susan Yung

    2011-01-01

    Full Text Available During peritoneal dialysis (PD, constant exposure of mesothelial cells to bioincompatible PD solutions results in the denudation of the mesothelial monolayer and impairment of mesothelial cell function. Hyaluronan, a major component of extracellular matrices, is synthesized by mesothelial cells and contributes to remesothelialization, maintenance of cell phenotype, and tissue remodeling and provides structural support to the peritoneal membrane. Chronic peritoneal inflammation is observed in long-term PD patients and is associated with increased hyaluronan synthesis. During inflammation, depolymerization of hyaluronan may occur with the generation of hyaluronan fragments. In contrast to native hyaluronan which offers a protective role to the peritoneum, hyaluronan fragments exacerbate inflammatory and fibrotic processes and therefore assist in the destruction of the tissue. This paper will discuss the contribution of mesothelial cells to peritoneal membrane alterations that are induced by PD and the putative role of hyaluronan in these processes.

  3. Visible light crosslinking of methacrylated hyaluronan hydrogels for injectable tissue repair.

    Science.gov (United States)

    Fenn, Spencer L; Oldinski, Rachael A

    2016-08-01

    Tissue engineering hydrogels are primarily cured in situ using ultraviolet (UV) radiation which limits the use of hydrogels as drug or cell carriers. Visible green light activated crosslinking systems are presented as a safe alternative to UV photocrosslinked hydrogels, without compromising material properties such as viscosity and stiffness. The objective of this study was to fabricate and characterize photocrosslinked hydrogels with well-regulated gelation kinetics and mechanical properties for the repair or replacement of soft tissue. An anhydrous methacrylation of hyaluronan (HA) was performed to control the degree of modification (DOM) of HA, verified by (1) H-NMR spectroscopy. UV-activated crosslinking was compared to visible green light activated crosslinking. While the different photocrosslinking techniques resulted in varied crosslinking times, comparable mechanical properties of UV and green light activated crosslinked hydrogels were achieved using each photocrosslinking method by adjusting time of light exposure. Methacrylated HA (HA-MA) hydrogels of varying molecular weight, DOM, and concentration exhibited compressive moduli ranging from 1 kPa to 116 kPa, for UV crosslinking, and 3 kPa to 146 kPa, for green light crosslinking. HA-MA molecular weight and concentration were found to significantly influence moduli values. HA-MA hydrogels did not exhibit any significant cytotoxic effects toward human mesenchymal stem cells. Green light activated crosslinking systems are presented as a viable method to form natural-based hydrogels in situ. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1229-1236, 2016.

  4. Green synthesis, characterization, and anticancer activity of hyaluronan/zinc oxide nanocomposites

    Directory of Open Access Journals (Sweden)

    Namvar F

    2016-07-01

    Full Text Available Farideh Namvar,1,2 Susan Azizi,3 Heshu Sulaiman Rahman,4–6 Rosfarizan Mohamad,1,3 Abdullah Rasedee,4 Mozhgan Soltani,2 Raha Abdul Rahim71Institute of Tropical Forestry and Forest Products (INTROP, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia; 2Research Center for Animal Development Applied Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran; 3Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, 4Department of Veterinary Laboratory Diagnosis, Faculty of Veterinary Medicine, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia; 5Department of Clinic and Internal Medicine, College of Veterinary Medicine, University of Sulaimani, 6Department of Laboratory Medical Sciences, Komar University of Science and Technology, Sulaimani City, Kurdistan Region, Northern Iraq; 7Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia Abstract: The study describes an in situ green biosynthesis of zinc oxide nanocomposite using the seaweed Sargassum muticum water extract and hyaluronan biopolymer. The morphology and optical properties of the hyaluronan/zinc oxide (HA/ZnO nanocomposite were determined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet–vis analysis. Electron microscopy and X-ray diffraction analysis showed that the zinc oxide nanoparticles were polydispersed with a mean size of 10.2±1.5 nm. The nanoparticles were mostly hexagonal in crystalline form. The HA/ZnO nanocomposite showed the absorption properties in the ultraviolet zone that is ascribed to the band gap of zinc oxide nanocomposite. In the cytotoxicity study, cancer cells, pancreatic adenocarcinoma (PANC-1, ovarian adenocarcinoma (CaOV-3, colonic adenocarcinoma (COLO205, and acute promyelocytic leukemia (HL-60 cells

  5. Hyaluronan synthesis is necessary for autoreactive T-cell trafficking, activation, and Th1 polarization.

    Science.gov (United States)

    Kuipers, Hedwich F; Rieck, Mary; Gurevich, Irina; Nagy, Nadine; Butte, Manish J; Negrin, Robert S; Wight, Thomas N; Steinman, Lawrence; Bollyky, Paul L

    2016-02-02

    The extracellular matrix polysaccharide hyaluronan (HA) accumulates at sites of autoimmune inflammation, including white matter lesions in multiple sclerosis (MS), but its functional importance in pathogenesis is unclear. We have evaluated the impact of 4-methylumbelliferone (4-MU), an oral inhibitor of HA synthesis, on disease progression in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Treatment with 4-MU decreases the incidence of EAE, delays its onset, and reduces the severity of established disease. 4-MU inhibits the activation of autoreactive T cells and prevents their polarization toward a Th1 phenotype. Instead, 4-MU promotes polarization toward a Th2 phenotpye and induction of Foxp3(+) regulatory T cells. Further, 4-MU hastens trafficking of T cells through secondary lymphoid organs, impairs the infiltration of T cells into the CNS parenchyma, and limits astrogliosis. Together, these data suggest that HA synthesis is necessary for disease progression in EAE and that treatment with 4-MU may be a potential therapeutic strategy in CNS autoimmunity. Considering that 4-MU is already a therapeutic, called hymecromone, that is approved to treat biliary spasm in humans, we propose that it could be repurposed to treat MS.

  6. Efficacy of platelet-rich plasma gel and hyaluronan hydrogel as carriers of electrically polarized hydroxyapatite microgranules for accelerating bone formation.

    Science.gov (United States)

    Ohba, Seiko; Wang, Wei; Itoh, Soichiro; Takagi, Yuzo; Nagai, Akiko; Yamashita, Kimihiro

    2012-11-01

    The technology for electrical polarization and characterization of hydroxyapatite (HA) microgranules has been developed. This study aimed to examine and compare the efficacy of composites comprising electrically polarized HA (pHA) microgranules and platelet-rich plasma (PRP) or hyaluronan (HAN) in osteoconductivity. Composites of HA microgranules with or without electrical polarization and either PRP or HAN (PRP+pHA, PRP+HA, HAN+pHA, and HAN+HA, respectively), as well as pHA and HA microgranules were implanted randomly into holes created in the medial femoral condyle or tibial tuberosity of rabbits. As a control, PRP or HAN gel alone was implanted, or the bone holes were left empty. Each group included six animals. After 6 weeks, histological examination was performed, and osteoclastic and osteoblastic cell activities were assessed by cell counting. Although PRP alone could not induce bone formation, PRP+pHA and PRP+HA composites, especially the former, activated osteogenic cells and enhanced bone formation. This effect was not prominent in the HAN+pHA and HAN+HA composites. PRP+HA composites formed a gel in which the ceramic particles were dispersed and entrapped in the fibrin network of PRP. It is assumed that these particles provide scaffolds for osteogenic cells, and when electrically polarized, can activate the cells in co-operation with the positive effects of the PRP, resulting in enhanced bone formation. Conversely, it is conceivable that this composite gel cannot act as an accelerator for woven bone formation, because HAN with low viscoelasticity is absorbed rapidly after implantation, the hydrated network containing HA microgranules is destroyed, and the HA microgranules effuse with HAN from the bone hole.

  7. Antioxidant effect of hyaluronan on polymorphonuclear leukocyte-derived reactive oxygen species is dependent on its molecular weight and concentration and mainly involves the extracellular space

    Directory of Open Access Journals (Sweden)

    Rafał Krasiński

    2009-05-01

    Full Text Available Introduction: Hyaluronan (HA, a component of the extracellular matrix, may regulate immune cell functions through its interactions with cellular receptors. Besides its effect on cytokine and chemokine production, its antioxidant properties have been described. However, the mechanisms of this are not fully elucidated. The aim of this study was to evaluate the relationship between HA concentration and molecular weight and its antioxidant properties towards human neutrophils. Also assessed was whether the antioxidant effect of HA is connected with a reduction in intracellular oxygen potential, which could indicate its direct effect on neutrophil respiratory burst.Materials/Methods: The relationship between HA’s antioxidant properties and its concentration and molecular weight was assessed by the luminol-enhanced chemiluminescence method (CL. To evaluate the effect of HA on intracellular oxygen potential selectively, the dihydrorhodamine 123 (DHR123 flow cytometric method was used.Results: Reduction of both HA molecular weight and its concentration decreased its antioxidant properties in the CL method. A selective effect of HA on intracellular oxygen potential measured by the DHR123 method was not shown.Conclusions: The antioxidant properties of HA are related to both its molecular weight and its concentration. The lack of an antioxidant effect of HA in the DHR123 test compared with a significant reduction in CL values at the same HA concentration suggests that HA acts mainly as a chemical ROI scavenger in the extracellular space.

  8. The role of hyaluronan in the pathobiology and treatment of respiratory disease.

    Science.gov (United States)

    Garantziotis, Stavros; Brezina, Martin; Castelnuovo, Paolo; Drago, Lorenzo

    2016-05-01

    Hyaluronan, a ubiquitous naturally occurring glycosaminoglycan, is a major component of the extracellular matrix, where it participates in biological processes that include water homeostasis, cell-matrix signaling, tissue healing, inflammation, angiogenesis, and cell proliferation and migration. There are emerging data that hyaluronan and its degradation products have an important role in the pathobiology of the respiratory tract. We review the role of hyaluronan in respiratory diseases and present evidence from published literature and from clinical practice supporting hyaluronan as a novel treatment for respiratory diseases. Preliminary data show that aerosolized exogenous hyaluronan has beneficial activity against airway inflammation, protects against bronchial hyperreactivity and remodeling, and disrupts the biofilm associated with chronic infection. This suggests a role in airway diseases with a predominant inflammatory component such as rhinosinusitis, asthma, chronic obstructive pulmonary disease, cystic fibrosis, and primary ciliary dyskinesia. The potential for hyaluronan to complement conventional therapy will become clearer when data are available from controlled trials in larger patient populations.

  9. Hyaluronan microgel as a potential carrier for protein sustained delivery by tailoring the crosslink network

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chunhong [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Zhao, Jianhao, E-mail: jhzhao@jnu.edu.cn [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Tu, Mei; Zeng, Rong; Rong, Jianhua [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

    2014-03-01

    Hyaluronan (HA) microgels with different crosslink network, i.e. HGPs-1, HGPs-1.5, HGPs-3, HGPs-6 and HGPs-15, were synthesized using divinyl sulfone (DVS) as the crosslinker in an inverse microemulsion system for controlling the sustained delivery of bovine serum albumin (BSA). With increasing the crosslinker content, the average particle size slightly increased from 1.9 ± 0.3 μm to 3.6 ± 0.5 μm by dynamic laser scattering analysis. However, the crosslinker content had no significant effect on the morphology of HA microgels by scanning and transmission electron microscopes. Fourier transform infrared spectroscopy and elemental analysis proved more sulfur participated in the crosslink reaction when raising the crosslinker amount. The water swelling test confirmed the increasing crosslink density with the crosslinker content by calculating the average molecular weight between two crosslink points to be 8.25 ± 2.51 × 10{sup 5}, 1.26 ± 0.43 × 10{sup 5}, 0.96 ± 0.09 × 10{sup 5}, 0.64 ± 0.03 × 10{sup 5}, and 0.11 ± 0.01 × 10{sup 5} respectively. The degradation of HA microgels by hyaluronidase slowed down by enhancing the crosslink density, only about 5% of HGPs-15 was degraded as opposed to over 90% for HGPs-1. BSA loading had no obvious influence on the surface morphology of HA microgels but seemed to induce their aggregation. The increase of crosslink density decreased the BSA loading capacity but facilitated its long-term sustained delivery. When the molar ratio of DVS to repeating unit of HA reached 3 or higher, similar delivery profiles were obtained. Among all these HA microgels, HGPs-3 was the optimal carrier for BSA sustained delivery in this system because it possessed both high BSA loading capacity and long-term delivery profile simultaneously. - Highlights: • HA microgels with different crosslink densities were prepared. • The crosslinker content had little effect on the morphology and size of HA microgels. • The crosslink density

  10. Síndrome HaNDL / HaNDL Syndrome / Síndrome HaNDL

    Directory of Open Access Journals (Sweden)

    Camilo Ernesto Barros-Gutiérrez, MD., Esp.

    2015-03-01

    Full Text Available Introducción: El Síndrome HaNDL (Headache and neurologic deficits with cerebroespinal fluid lymphocytosis por sus siglas en inglés, es una patología que cursa con cefalea, focalización neurológica y linfocitosis en el líquido cefalorraquídeo. Objetivo: este artículo busca presentar un caso de Síndrome de HaNDL, puesto que esta condición nosológica implica un reto diagnóstico. Resultados y conclusiones: Se presenta el caso de un paciente con diagnóstico de síndrome de HaNDL los hallazgos al examen físico y del líquido cefalorraquídeo. [Barros-Gutiérrez CE, Silva-Monsalve E, Gualtero-Trujillo S. Síndrome HaNDL. MedUNAB 2015; 17(3: xx-xx]. Introduction: The syndrome of transient Headache and Neurological Deficits with cerebrospinal fluid Lymphocytosis, is a pathology that presents cephalalgia, neurological focalization and lymphocytes in the cerebrospinal fluid. Objective: This article presents a HaNDL Syndrome case, since this nosological condition implies a diagnostic challenge. Results and conclusions: A case of a patient with HaNDL syndrome diagnosis, physical examination findings and cerebrospinal fluid are presented. [Barros-Gutiérrez CE, Silva-Monsalve E, Gualtero-Trujillo S. HaNDL Syndrome. MedUNAB 2015; 17(3: xx-xx]. Introdução: A síndrome de HaNDL (Headache and neurologic déficits with cerebrospinal fluid lymphocytosis por sua sigla em inglês é uma doença que causa dor de cabeça, foco neurológico e linfocitose no líquido cefalorraquidiano. Objetivo: Este artigo tem como objetivo apresentar um caso de Síndrome de HaNDL, uma vez que esta condição nosológica envolve um desafio diagnóstico. Resultados e conclusões: Apresenta-se o caso de um paciente diagnosticado com a síndrome de HaNDL, o encontrado no exame físico e o líquido cefalorraquidiano. [Barros-Gutiérrez CE, Silva-Monsalve E, Gualtero-Trujillo S. Síndrome HaNDL. MedUNAB 2015; 17(3: xx-xx].

  11. Hyaluronan/Tween 80-assisted synthesis of silver nanoparticles for biological application

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui-Jun [Fudan University, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry (China); Zhang, An-Qi [Fudan University, Department of Materials Science (China); Sui, Li [University of Shanghai for Science and Technology, School of Medical Instrument and Food Engineering (China); Qian, Dong-Jin; Chen, Meng, E-mail: chenmeng@fudan.edu.cn [Fudan University, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry (China)

    2015-02-15

    Water-soluble and well-stabilized silver nanoparticles (NPs) of small size have been synthesized using hyaluronan (HA) and Tween 80 as reducing and stabilizing agents. The effect of reaction conditions on the formation process of silver NPs was studied, and an aggregative growth mechanism of the silver NPs dominated in HA/Tween 80 system at pH 12 has been proposed. The obtained Ag NPs were characterized by UV–Vis spectroscopy, transmission electron microscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Moreover, the stability of the HA–Tween 80-silver NPs in normal saline was also studied, and a flexible blend membrane containing chitosan, gelatin, and the HA–Tween 80-silver NPs was prepared for further biological applications. Due to the high specific surface area and improved stability of silver NPs, the chitosan–gelatin-silver membrane has shown high antibacterial activity for strains of Escherichia coli. The cell viability tests indicate that the polymer membrane is non-cytotoxic to HepG2 cells, which might be attributed to its good biocompatibility.

  12. Fabrication of Hyaluronan-Poly(vinylphosphonic acid-Chitosan Hydrogel for Wound Healing Application

    Directory of Open Access Journals (Sweden)

    Dang Hoang Phuc

    2016-01-01

    Full Text Available A new hydrogel made of hyaluronan, poly(vinylphosphonic acid, and chitosan (HA/PVPA/CS hydrogel was fabricated and characterized to be used for skin wound healing application. Firstly, the component ratio of hydrogel was studied to optimize the reaction effectiveness. Next, its microstructure was observed by light microscope. The chemical interaction in hydrogel was evaluated by nuclear magnetic resonance spectroscopy and Fourier transform-infrared spectroscopy. Then, a study on its degradation rate was performed. After that, antibacterial activity of the hydrogel was examined by agar diffusion method. Finally, in vivo study was performed to evaluate hydrogel’s biocompatibility. The results showed that the optimized hydrogel had a three-dimensional highly porous structure with the pore size ranging from about 25 µm to less than 125 µm. Besides, with a degradation time of two weeks, it could give enough time for the formation of extracellular matrix framework during remodeling stages. Furthermore, the antibacterial test showed that hydrogel has antimicrobial activity against E. coli. Finally, in vivo study indicated that the hydrogel was not rejected by the immune system and could enhance wound healing process. Overall, HA/PVPA/CS hydrogel was successfully fabricated and results implied its potential for wound healing applications.

  13. Interleukin-10-mediated regenerative postnatal tissue repair is dependent on regulation of hyaluronan metabolism via fibroblast-specific STAT3 signaling.

    Science.gov (United States)

    Balaji, Swathi; Wang, Xinyi; King, Alice; Le, Louis D; Bhattacharya, Sukanta S; Moles, Chad M; Butte, Manish J; de Jesus Perez, Vinicio A; Liechty, Kenneth W; Wight, Thomas N; Crombleholme, Timothy M; Bollyky, Paul L; Keswani, Sundeep G

    2017-03-01

    The cytokine IL-10 has potent antifibrotic effects in models of adult fibrosis, but the mechanisms of action are unclear. Here, we report a novel finding that IL-10 triggers a signal transducer and activator of transcription 3 (STAT3)-dependent signaling pathway that regulates hyaluronan (HA) metabolism and drives adult fibroblasts to synthesize an HA-rich pericellular matrix, which mimics the fetal regenerative wound healing phenotype with reduced fibrosis. By using cre-lox-mediated novel, inducible, fibroblast-, keratinocyte-, and wound-specific STAT3-knockdown postnatal mice-plus syngeneic fibroblast cell-transplant models-we demonstrate that the regenerative effects of IL-10 in postnatal wounds are dependent on HA synthesis and fibroblast-specific STAT3-dependent signaling. The importance of IL-10-induced HA synthesis for regenerative wound healing is demonstrated by inhibition of HA synthesis in a murine wound model by administering 4-methylumbelliferone. Although IL-10 and STAT3 signaling were intact, the antifibrotic repair phenotype that is induced by IL-10 overexpression was abrogated in this model. Our data show a novel role for IL-10 beyond its accepted immune-regulatory mechanism. The opportunity for IL-10 to regulate a fibroblast-specific formation of a regenerative, HA-rich wound extracellular matrix may lead to the development of innovative therapies to attenuate postnatal fibrosis in organ systems or diseases in which dysregulated inflammation and HA intersect.-Balaji, S., Wang, X., King, A., Le, L. D., Bhattacharya, S. S., Moles, C. M., Butte, M. J., de Jesus Perez, V. A., Liechty, K. W., Wight, T. N., Crombleholme, T. M., Bollyky, P. L., Keswani, S. G. Interleukin-10-mediated regenerative postnatal tissue repair is dependent on regulation of hyaluronan metabolism via fibroblast-specific STAT3 signaling. © The Author(s).

  14. Radiosensitizing and Hyperthermic Properties of Hyaluronan Conjugated, Dextran-Coated Ferric Oxide Nanoparticles: Implications for Cancer Stem Cell Therapy

    Directory of Open Access Journals (Sweden)

    Ranjeeta Thapa

    2015-01-01

    Full Text Available Cytotoxicity, radiosensitivity, and hyperthermia sensitivity of hyaluronan-mediated dextran-coated super paramagnetic iron oxide nanoparticles (HA-DESPIONs were assessed in CD44-expressing head and neck squamous cell carcinoma (HNSCC cell lines at clinically relevant radiation dose and temperatures. Low-passage HNSCC cells were exposed to HA-DESPIONs and cytotoxicity was assessed using MTT assay. Radiosensitizing properties of graded doses of HA-DESPIONs were assessed in both unsorted and CD44-sorted cells using clonogenic assay in combination with 2 Gy exposure to X-rays. Hyperthermia-induced toxicity was measured at 40°C, 41°C, and 42°C using clonogenic assay. Cell death was assessed 24 hours after treatment using a flow cytometry-based apoptosis analysis. Results showed that HA-DESPIONs were nontoxic at moderate concentrations and did not directly radiosensitize the cell lines. Further, there was no significant difference in the radiosensitivity of CD44high and CD44low cells. However, HA-DESPIONs enhanced the effect of hyperthermia which resulted in reduced cell survival that appeared to be mediated through apoptosis. We demonstrated that HA-DESPIONs are nontoxic and although they do not enhance radiation sensitivity, they did increase the effect of local hyperthermia. These results support further development of drug-attached HA-DESPIONs in combination with radiation for targeting cancer stem cells (CSCs and the development of an alternating magnetic field approach to activate the HA-DESPIONs attached to CSCs.

  15. Transient exposure of pulmonary surfactant to hyaluronan promotes structural and compositional transformations into a highly active state.

    Science.gov (United States)

    Lopez-Rodriguez, Elena; Cruz, Antonio; Richter, Ralf P; Taeusch, H William; Pérez-Gil, Jesús

    2013-10-11

    Pulmonary surfactant is a lipid-protein complex that lowers surface tension at the respiratory air-liquid interface, stabilizing the lungs against physical forces tending to collapse alveoli. Dysfunction of surfactant is associated with respiratory pathologies such as acute respiratory distress syndrome or meconium aspiration syndrome where naturally occurring surfactant-inhibitory agents such as serum, meconium, or cholesterol reach the lung. We analyzed the effect of hyaluronan (HA) on the structure and surface behavior of pulmonary surfactant to understand the mechanism for HA-promoted surfactant protection in the presence of inhibitory agents. In particular, we found that HA affects structural properties such as the aggregation state of surfactant membranes and the size, distribution, and order/packing of phase-segregated lipid domains. These effects do not require a direct interaction between surfactant complexes and HA and are accompanied by a compositional reorganization of large surfactant complexes that become enriched with saturated phospholipid species. HA-exposed surfactant reaches very high efficiency in terms of rapid and spontaneous adsorption of surfactant phospholipids at the air-liquid interface and shows significantly improved resistance to inactivation by serum or cholesterol. We propose that physical effects pertaining to the formation of a meshwork of interpenetrating HA polymer chains are responsible for the changes in surfactant structure and composition that enhance surfactant function and, thus, resistance to inactivation. The higher resistance of HA-exposed surfactant to inactivation persists even after removal of the polymer, suggesting that transient exposure of surfactant to polymers like HA could be a promising strategy for the production of more efficient therapeutic surfactant preparations.

  16. The interaction between LYVE-1 with hyaluronan on the cell surface may play a role in the diversity of adhesion to cancer cells.

    Directory of Open Access Journals (Sweden)

    Yan Du

    Full Text Available Hyaluronan (HA, a simple disaccharide unit, can polymerize and is considered a primary component of the extracellular matrix, which has a wide range of biological functions. In recent years, HA was found on the surface of tumor cells. According to previous reports, differing HA content on the cell surface of tumor cells is closely related to lymph node metastases, but the mechanisms mediating this process remained unclear. This research intended to study the surface content of HA on tumor cells and analyze cell adhesive changes caused by the interaction between HA and its lymphatic endothelial receptor (LYVE-1. We screened and observed high HA content on HS-578T breast cells and low HA content on MCF-7 breast cells through particle exclusion, immunofluorescence and flow cytometry experiments. The expression of LYVE-1, the lymph-vessel specific HA receptor, was consistent with our previous report and enhanced the adhesion of HA(high-HS-578T cells to COS-7(LYVE-1(+ through HA in cell static adhesion and dynamic parallel plate flow chamber experiments. MCF-7 breast cells contain little HA on the surface; however, our results showed little adhesion difference between MCF-7 cells and COS-7(LYVE-1(+ and COS-7(LYVE-1(- cells. Similar results were observed concerning the adhesion of HS-578T cells or MCF-7 cells to SVEC4-10 cells. Furthermore, we observed for the first time that the cell surface HA content of high transfer tumor cells was rich, and we visualized the cross-linking of HA cable structures, which may activate LYVE-1 on lymphatic endothelial cells, promoting tumor adhesion. In summary, high-low cell surface HA content of tumor cells through the interaction with LYVE-1 leads to adhesion differences.

  17. Rheology and Confocal Reflectance Microscopy as Probes of Mechanical Properties and Structure during Collagen and Collagen/Hyaluronan Self-Assembly

    OpenAIRE

    Yang, Ya-Li; Kaufman, Laura J.

    2009-01-01

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37°C and 32°C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (tc), the slope of the growth phase (kg...

  18. Trinh T. Minh-ha

    DEFF Research Database (Denmark)

    Nelund, Sidsel; Trinh T, Minh-ha

    2012-01-01

    Born in Vietnam, Trinh T. Minh-ha is known as a filmmaker, composer and writer. Contributing generously to these art forms, she was also a pioneer in the 1980’s theoretical conceptualisation of the Other, verbalising especially the position of women in developing countries. 
 Currently, Trinh T. ...

  19. Therapeutic Targeting of Hyaluronan in the Tumor Stroma

    OpenAIRE

    2012-01-01

    The tumor stroma, consisting of non-malignant cells and the extracellular matrix, undergoes significant quantitative and qualitative changes throughout malignant transformation and tumor progression. With increasing recognition of the role of the tumor microenvironment in disease progression, stromal components of the tumor have become attractive targets for therapeutic intervention. Stromal accumulation of the glycosaminoglycan hyaluronan occurs in many tumor types and is frequently associat...

  20. Hyaluronan and calcium carbonate hybrid nanoparticles for colorectal cancer chemotherapy

    Science.gov (United States)

    Bai, Jinghui; Xu, Jian; Zhao, Jian; Zhang, Rui

    2017-09-01

    A hybrid drug delivery system (DDS) composed of hyaluronan and calcium carbonate (CC) was developed. By taking advantage of the tumor-targeting ability of hyaluronan and the drug-loading property of CC, the well-formed hyaluronan–CC nanoparticles were able to serve as a DDS targeting colorectal cancer with a decent drug loading content, which is beneficial in the chemotherapy of colorectal cancer. In this study, hyaluronan–CC nanoparticles smaller than 100 nm were successfully developed to load the wide-range anti-cancer drug adriamycin (Adr) to construct hyaluronan–CC/Adr nanoparticles. On the other hand, we also found that hyaluronan–CC/Adr nanoparticles can possibly increase the uptake ratio of Adr into HT29 colorectal cancer cells when compared with hyaluronan-free nanoparticles (CC/Adr) via the CD44 receptor-mediated endocytosis via competitive uptake and in vivo imaging assays. Note that both in vitro (CCK-8 assay on HT29 cells) and in vivo (anti-cancer assay on HT-29 tumor-bearing nude mice model) experiments revealed that hyaluronan–CC/Adr nanoparticles exhibited stronger anti-cancer activity than free Adr or CC/Adr nanoparticles with minimized toxic side effects and preferable cancer-suppression potential.

  1. Sevoflurane mitigates shedding of hyaluronan from the coronary endothelium, also during ischemia/reperfusion: an ex vivo animal study

    Directory of Open Access Journals (Sweden)

    Chen C

    2016-04-01

    Full Text Available Congcong Chen,1,3 Daniel Chappell,2,3 Thorsten Annecke,2,3 Peter Conzen,2 Matthias Jacob,2,3 Ulrich Welsch,4 Bernhard Zwissler,2 Bernhard F Becker3 1Department of Anesthesiology, Second Affiliated Hospital of Zhejiang University, Hangzhou, People's Republic of China; 2Clinic of Anesthesiology, Ludwig-Maximilians-University, Munich, Germany; 3Walter-Brendel-Centre of Experimental Medicine, Ludwig-Maximilians-University, Munich, Germany; 4Institute of Anatomy, Ludwig-Maximilians-University, Munich, Germany Abstract: Glycosaminoglycan hyaluronan (HA, a major constituent of the endothelial glycocalyx, helps to maintain vascular integrity. Preconditioning the heart with volatile anesthetic agents protects against ischemia/reperfusion injury. We investigated a possible protective effect of sevoflurane on the glycocalyx, especially on HA. The effect of pre-ischemic treatment with sevoflurane (15 minutes at 2% vol/vol gas on shedding of HA was evaluated in 28 isolated, beating guinea pig hearts, subjected to warm ischemia (20 minutes at 37°C followed by reperfusion (40 minutes, half with and half without preconditioning by sevoflurane. HA concentration was measured in the coronary effluent. Over the last 20 minutes of reperfusion hydroxyethyl starch (1 g% was continuously infused and the epicardial transudate collected over the last 5 minutes for measuring the colloid extravasation. Additional hearts were fixed by perfusion after the end of reperfusion for immunohistology and electron microscopy. Sevoflurane did not significantly affect post-ischemic oxidative stress, but strongly inhibited shedding of HA during the whole period, surprisingly even prior to ischemia. Immunohistology demonstrated that heparan sulfates and SDC1 of the glycocalyx were also preserved by sevoflurane. Electron microscopy revealed shedding of glycocalyx caused by ischemia and a mostly intact glycocalyx in hearts exposed to sevoflurane. Coronary vascular permeability of the

  2. Force spectroscopy of hyaluronan by atomic force microscopy: from hydrogen-bonded networks toward single-chain behavior.

    Science.gov (United States)

    Giannotti, Marina I; Rinaudo, Marguerite; Vancso, G Julius

    2007-09-01

    The conformational behavior of hyaluronan (HA) polysaccharide chains in aqueous NaCl solution was characterized directly at the single-molecule level. This communication reports on one of the first single-chain atomic force microscopy (AFM) experiments performed at variable temperatures, investigating the influence of the temperature on the stability of the HA single-chain conformation. Through AFM single-molecule force spectroscopy, the temperature destabilization of a local structure was proven. This structure involved a hydrogen-bonded network along the polymeric chain, with hydrogen bonds between the polar groups of HA and possibly water, and a change from a nonrandom coil to a random coil behavior was observed when increasing the temperature from 29 +/- 1 to 46 +/- 1 degrees C. As a result of the applied force, this superstructure was found to break progressively at room temperature. The use of a hydrogen-bonding breaker solvent demonstrated the hydrogen-bonded water-bridged nature of the network structure of HA single chains in aqueous NaCl solution.

  3. Chitin-Hyaluronan Nanoparticles: A Multifunctional Carrier to Deliver Anti-Aging Active Ingredients through the Skin

    Directory of Open Access Journals (Sweden)

    Pierfrancesco Morganti

    2014-07-01

    Full Text Available The paper describes the process to produce Chitin Nanofibril-Hyaluronan nanoparticles (CN-HA, showing their ability to easily load active ingredients, facilitate penetration through the skin layers, and increase their effectiveness and safety as an anti-aging agent. Size and characterization of CN-HA nanoparticles were determined by Scanning Electron Microscopy (SEM and Zetasizer, while encapsulation efficiency and loading capacity of the entrapped ingredients were controlled by chromatographic and spectrophotometric methods. Safeness was evidenced on fibroblasts and keratinocytes culture viability by the MTT (Methylthiazol assay; anti-aging activity was evaluated in vitro measuring antioxidant capacity, anti-collagenase activity, and metalloproteinase and pro-inflammatory release; efficacy was shown in vivo by a double-blind vehicle-controlled study for 60 days on 60 women affected by photo-aging. In addition, the CN-HA nanoparticles have shown interesting possibility to be used as active ingredients, for designing and making advanced medication by the electrospinning technology, as well as to produce transparent films for food packaging, by the casting method, and can be used also in their dry form as tissues or films without adding preservatives. These unusual CN-HA nanoparticles obtained from the use of raw materials of waste origin may offer an unprecedented occasion for making innovative products, ameliorating the quality of life, reducing pollution and safeguarding the environment’s integrity.

  4. Effects of tenoxicam and aspirin on the metabolism of proteoglycans and hyaluronan in normal and osteoarthritic human articular cartilage.

    Science.gov (United States)

    Manicourt, D H; Druetz-Van Egeren, A; Haazen, L; Nagant de Deuxchaisnes, C

    1994-01-01

    1. As nonsteroidal anti-inflammatory drugs may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan (PG) and hyaluronan (HA) molecules produced by tenoxicam and aspirin in human normal cartilage explants and in osteoarthritic (OA) cartilage from age-matched donors. 2. Explants were sampled from the medial femoral condyle and were classified by use of Mankin's histological-histochemical grading system. Cartilage specimens were normal in 10 subjects, exhibited moderate OA (MOA) in 10 and had severe OA (SOA) in 10. 3. Cartilage explants were pulsed with [3H]-glucosamine and chased in the absence and in the presence of either aspirin (190 micrograms ml-1) or tenoxicam (4-16 micrograms ml-1). After papain digestion, the labelled chondroitin sulphate ([3H]-PGs) and HA([3H]-HA) molecules present in the tissue and media were purified by anion-exchange chromatography. 4. In normal cartilage as well as in explants with MOA and SOA aspirin reduced more strongly PG and HA synthesis than the loss of [3H]-HA and [3H]-PGs. 5. In normal cartilage, tenoxicam did not affect PG metabolism whereas it reduced HA synthesis in a dose-dependent manner and did not change or even increased the net loss of [3H]-HA. In contrast, in OA cartilage, tenoxicam produced a stronger reduction in the loss of [3H]-PGs than in PG synthesis and this decrease occurred at lower concentrations in cartilage with SOA (4-8 micrograms ml-1) than in cartilage with MOA (8-16 micrograms ml-1).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7889262

  5. Phase I-II clinical trial of hyaluronan-cisplatin nanoconjugate in dogs with naturally occurring malignant tumors.

    Science.gov (United States)

    Cai, Shuang; Zhang, Ti; Forrest, W C; Yang, Qiuhong; Groer, Chad; Mohr, Eva; Aires, Daniel J; Axiak-Bechtel, Sandra M; Flesner, Brian K; Henry, Carolyn J; Selting, Kimberly A; Tate, Deborah; Swarz, Jeffrey A; Bryan, Jeffrey N; Forrest, M Laird

    2016-09-01

    OBJECTIVE To conduct a phase I-II clinical trial of hyaluronan-cisplatin nanoconjugate (HA-Pt) in dogs with naturally occurring malignant tumors. ANIMALS 18 healthy rats, 9 healthy mice, and 16 dogs with cancer. PROCEDURES HA-Pt was prepared and tested by inductively coupled plasma mass spectrometry; DNA-platinum adduct formation and antiproliferation effects of cisplatin and HA-Pt were compared in vitro. Effects of cisplatin (IV) and HA-Pt (SC) in rodents were tested by clinicopathologic assays. In the clinical trial, dogs with cancer received 1 to 4 injections of HA-Pt (10 to 30 mg/m(2), intratumoral or peritumoral, q 3 wk). Blood samples were collected for pharmacokinetic analysis; CBC, serum BUN and creatinine concentration measurement, and urinalysis were conducted before and 1 week after each treatment. Some dogs underwent hepatic enzyme testing. Tumors were measured before the first treatment and 3 weeks after each treatment to assess response. RESULTS No adverse drug effects were detected in pretrial assessments in rodents. Seven of 16 dogs completed the study; 3 had complete tumor responses, 3 had stable disease, and 1 had progressive disease. Three of 7 dogs with oral and nasal squamous cell carcinoma (SCC) that completed the study had complete responses. Myelosuppression and cardiotoxicosis were identified in 6 and 2 dogs, respectively; none had nephrotoxicosis. Four of 5 dogs with hepatic enzymes assessed had increased ALT activities, attributed to diaquated cisplatin products in the HA-Pt. Pharmacokinetic data fit a 3-compartment model. CONCLUSIONS AND CLINICAL RELEVANCE HA-Pt treatment resulted in positive tumor responses in some dogs, primarily those with SCC. The adverse effect rate was high. IMPACT FOR HUMAN MEDICINE Oral SCC in dogs has characteristics similar to human head and neck SCC; these results could be useful in developing human treatments.

  6. Development of a complex hydrogel of hyaluronan and PVA embedded with silver nanoparticles and its facile studies on Escherichia coli.

    Science.gov (United States)

    Zhang, Fei; Wu, Juan; Kang, Ding; Zhang, Hongbin

    2013-01-01

    Novel nanocomposite hydrogels composed of hyaluronan (HA), poly(vinyl alcohol) (PVA) and silver nanoparticles were prepared by several cycles of freezing and thawing. The nanocomposite was then characterised using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (XRD) and scanning electron microscopy (SEM). The complex hydrogels consisted of semi-interpenetrating network structures, with PVA microcrystallines as junction zones. By increasing the HA content, the crystallinity and melting temperature of the complex hydrogels decreased, whereas the glass transition temperatures of these materials increased because of the steric hindrance of HA and the occurrence of intermolecular interactions through hydrogen bonding between HA and PVA in the complex hydrogels. Swelling studies showed that in comparison with the swelling properties of the cryogels from PVA alone, those of the complex hydrogels can be significantly improved and presented in a pH-sensitive manner. In addition, silver nanoparticles were synthesised through UV-initiated photoreduction with HA functioning as a reducing agent and stabiliser. The silver nanoparticles were then incorporated in situ into the HA/PVA complex hydrogel matrix. The size and morphology of the as-prepared Ag nanoparticles were investigated through ultraviolet-visible light spectroscopy, transmission electron microscopy, XRD and thermogravimetric analysis. The experimental results indicated that silver nanoparticles 20-50 nm in size were uniformly dispersed in the hydrogel matrix. The antibacterial effects of the HA/PVA/Ag nanocomposite hydrogel against Escherichia coli were evaluated. The results show that this nanocomposite hydrogel possesses high antibacterial property and has a potential application as a wound dressing material.

  7. Trinh T. Minh-ha

    DEFF Research Database (Denmark)

    Nelund, Sidsel; Trinh T, Minh-ha

    2012-01-01

    Born in Vietnam, Trinh T. Minh-ha is known as a filmmaker, composer and writer. Contributing generously to these art forms, she was also a pioneer in the 1980’s theoretical conceptualisation of the Other, verbalising especially the position of women in developing countries. 
 Currently, Trinh T....... Minh-ha holds the post of Professor of Gender and Women's Studies, and of Rhetoric at the University of California, Berkeley. She has lived, among other places, in Vietnam, USA, France, Senegal, and Japan and this geographic diversity is reflected in her work, in which several countries have been...... for marginalised groups. However, she also moves in circles of documentary, cinema, feminist studies, postcolonial theory, contemporary visual art, literature, and music composition. This interview consists of 4 parts concerning positioning, research, and media, finally coming back to positioning again....

  8. Influence of water content and drying on the physical structure of native hyaluronan

    NARCIS (Netherlands)

    Prusova, A.; Vergeldt, F.J.; Kucerik, J.

    2013-01-01

    Hydration properties of semi-diluted hyaluronan were studied by means of time domain nuclear magnetic resonance. Based on the transverse proton relaxation times T2, the plasticization of hyaluronan which was precipitated by isopropylalcohol and dried in the oven have been determined at water content

  9. Systemic delivery of siRNA by hyaluronan-functionalized calcium phosphate nanoparticles for tumor-targeted therapy

    Science.gov (United States)

    Qiu, Chong; Wei, Wei; Sun, Jing; Zhang, Hai-Tao; Ding, Jing-Song; Wang, Jian-Cheng; Zhang, Qiang

    2016-06-01

    In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform spherical core-shell morphology with an approximate size of 170 nm and zeta potential of -12 mV. The coating of hydrophilic HA improved the physical stability of nanoparticles over one month due to the strong interactions between phosphonate and calcium. In vitro experiments demonstrated that the negatively charged CaP-AHA/siRNA NPs could effectively deliver EGFR-targeted siRNA into A549 cells through CD44-mediated endocytosis and significantly down-regulate the level of EGFR expression. Also, the internalized CaP-AHA/siRNA NPs exhibited a pH-responsive release of siRNA, indicating that the acidification of lysosomes probably facilitated the disassembling of nanoparticles and the resultant ions sharply increased the inner osmotic pressure and thus expedited the release of siRNA from late lysosomes into the cytoplasm. Furthermore, in vivo tumor therapy demonstrated that high accumulation of CaP-AHA/siEGFR NPs in tumor led to a significant tumor growth inhibition with a specific EGFR gene silencing effect after intravenous administration in nude mice xenografted with A549 tumor, along with a negligible body weight loss. These results suggested that the CaP-AHA/siRNA NPs could be an effective and safe systemic siRNA delivery system for a RNAi-based tumor targeted therapy strategy.In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform

  10. A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation

    Directory of Open Access Journals (Sweden)

    Brian G. Ballios

    2015-06-01

    Full Text Available The utility of stem cells and their progeny in adult transplantation models has been limited by poor survival and integration. We designed an injectable and bioresorbable hydrogel blend of hyaluronan and methylcellulose (HAMC and tested it with two cell types in two animal models, thereby gaining an understanding of its general applicability for enhanced cell distribution, survival, integration, and functional repair relative to conventional cell delivery in saline. HAMC improves cell survival and integration of retinal stem cell (RSC-derived rods in the retina. The pro-survival mechanism of HAMC is ascribed to the interaction of the CD44 receptor with HA. Transient disruption of the retinal outer limiting membrane, combined with HAMC delivery, results in significantly improved rod survival and visual function. HAMC also improves the distribution, viability, and functional repair of neural stem and progenitor cells (NSCs. The HAMC delivery system improves cell transplantation efficacy in two CNS models, suggesting broad applicability.

  11. Clustered Conserved Cysteines in Hyaluronan Synthase Mediate Cooperative Activation by Mg(2+) Ions and Severe Inhibitory Effects of Divalent Cations.

    Science.gov (United States)

    Tlapak-Simmons, Valarie L; Medina, Andria P; Baggenstoss, Bruce A; Nguyen, Long; Baron, Christina A; Weigel, Paul H

    2011-11-15

    Hyaluronan synthase (HAS) uses UDP-GlcUA and UDP-GlcNAc to make hyaluronan (HA). Streptococcus equisimilis HAS (SeHAS) contains four conserved cysteines clustered near the membrane, and requires phospholipids and Mg(2+) for activity. Activity of membrane-bound or purified enzyme displayed a sigmoidal saturation profile for Mg(2+) with a Hill coefficient of 2. To assess if Cys residues are important for cooperativity we examined the Mg(2+) dependence of mutants with various combinations of Cys-to-Ala mutations. All Cys-mutants lost the cooperative response to Mg(2+). In the presence of Mg(2+), other divalent cations inhibited SeHAS with different potencies (Cu(2+)~Zn(2+) >Co(2+) >Ni(2+) >Mn(2+) >Ba(2+) Sr(2+) Ca(2+)). Some divalent metal ions likely inhibit by displacement of Mg(2+)-UDP-Sugar complexes (e.g. Ca(2+), Sr(2+) and Ba(2+) had apparent Ki values of 2-5 mM). In contrast, Zn(2+) and Cu(2+) inhibited more potently (apparent Ki ≤ 0.2 mM). Inhibition of Cys-null SeHAS by Cu(2+), but not Zn(2+), was greatly attenuated compared to wildtype. Double and triple Cys-mutants showed differing sensitivities to Zn(2+) or Cu(2+). Wildtype SeHAS allowed to make HA prior to exposure to Zn(2+) or Cu(2+) was protected from inhibition, indicating that access of metal ions to sensitive functional groups was hindered in processively acting HA•HAS complexes. We conclude that clustered Cys residues mediate cooperative interactions with Mg(2+) and that transition metal ions inhibit SeHAS very potently by interacting with one or more of these -SH groups.

  12. Lo que se ha hecho

    OpenAIRE

    Alvarado A. Víctor Hernando

    1992-01-01

    Después de transcurrido el primer módulo e iniciado el segundo, en el Curso de Postgrado en DERECHO ADMINISTRATIVO, resulta conveniente, formular algunas reflexiones sobre el avance del programa en su etapa inicial. El programa aprobado por el Instituto Colombiano para el Fomento de la Educación Superior -ICFES-, a desarrollarse en cuatro (4) MODULOS semestrales cada uno, requiriéndose dos (2) años para su cumplimiento, nos ha permitido ver que reúne las exigencias que la Universidad pretend...

  13. Lo que se ha hecho

    OpenAIRE

    1992-01-01

    Después de transcurrido el primer módulo e iniciado el segundo, en el Curso de Postgrado en DERECHO ADMINISTRATIVO, resulta conveniente, formular algunas reflexiones sobre el avance del programa en su etapa inicial. El programa aprobado por el Instituto Colombiano para el Fomento de la Educación Superior -ICFES-, a desarrollarse en cuatro (4) MODULOS semestrales cada uno, requiriéndose dos (2) años para su cumplimiento, nos ha permitido ver que reúne las exigencias que la Universidad pretend...

  14. The hyaluronan and proteoglycan link proteins: Organizers of the brain extracellular matrix and key molecules for neuronal function and plasticity.

    Science.gov (United States)

    Oohashi, Toshitaka; Edamatsu, Midori; Bekku, Yoko; Carulli, Daniela

    2015-12-01

    The hyaluronan and proteoglycanbinding link protein (Hapln) is a key molecule in the formation and control of hyaluronan-based condensed perineuronal matrix in the adult brain. This review summarizes the recent advances in understanding the role of Haplns in the formation and control of two distinct types of perineuronal matrices, one for "classical" PNN and the other for the specialized extracellular matrix (ECM) at the node of Ranvier in the central nervous system (CNS). We introduce the structural components of each ECM organization including the basic concept of supramolecular structure named "HLT model". We furthermore summarize the developmental and physiological role of perineuronal ECMs from the studies of Haplns and related molecules. Finally, we also discuss the potential mechanism modulating PNNs in the adult CNS. This layer of organized matrices may exert a direct effect via core protein or sugar moiety from the structure or by acting as a binding site for biologically active molecules, which are important for neuronal plasticity and saltatory conduction. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Divergent temporal expression of hyaluronan metabolizing enzymes and receptors with craniotomy vs. controlled cortical impact injury in rat brain: A pilot study

    Directory of Open Access Journals (Sweden)

    Guoqiang eXing

    2014-09-01

    Full Text Available Traumatic brain injury triggers many secondary changes in tissue biology which ultimately determine the extent of injury and clinical outcome. Hyaluronan (hyaluronic acid, HA is a protective cementing gel present in the intercellular spaces whose degradation has been reported as a causative factor in tissue damage. Yet little is known about the expression and activities of genes involved in HA catabolism after TBI. Young adult male Sprague-Dawley rats were assigned to three groups: naïve control, craniotomy and, controlled-cortical impact-induced TBI (CCI-TBI. Four animals per group were sacrificed at 4h, 1d, 3d and 7d post CCI. The mRNA expression of hyaluronan synthases (HAS1-3, hyaluronidases (enzymes for HA degradation, HYAL 1-4 & PH20 and CD44 and RHAMM (membrane receptors for HA signaling and removal were determined using real-time PCR. Compared to the naïve controls, expression of HAS1 and HAS2 mRNA, but not HAS3 mRNA increased significantly following craniotomy alone and following CCI with differential kinetics. Expression of HAS2 mRNA increased significantly in the ipsilateral brain at 1d and 3d post CCI. HYAL1 mRNA expression also increased significantly in the craniotomy group and in the contralateral CCI at 1d and 3d post CCI. CD44 mRNA expression increased significantly in the ipsilateral CCI at 4h, 1d, 3d and 7d post CCI (up to 25 fold increase. These data suggest a dynamic regulation and role for HA metabolism in secondary responses to traumatic brain injury.

  16. Dynamics of hyaluronan, CD44, and inflammatory cells in the rat kidney after ischemia/reperfusion injury.

    Science.gov (United States)

    Declèves, Anne-Emilie; Caron, Nathalie; Nonclercq, Denis; Legrand, Alexandre; Toubeau, Gérard; Kramp, Ronald; Flamion, Bruno

    2006-07-01

    Ischemia/reperfusion (I/R) injury in the kidney involves hemodynamic and cellular dysfunctions as well as leukocyte infiltration. Functional recovery occurs via cell proliferation and/or migration. To determine the roles of hyaluronan (HA) and its main receptor CD44 in renal postischemic processes, we compared their localization and expression with that of neutrophils, macrophages, and PCNA-positive (regenerative) cells as characterized by immunohistochemistry, up to 28 days after I/R in uninephrectomized rats. Observations covered all kidney zones, i.e. cortex (C), outer and inner stripes of outer medulla (OSOM, ISOM), and inner medulla (IM). In controls, HA was localized to the interstitium of IM and ISOM, and CD44 was mostly present on the basolateral membranes of collecting ducts in ISOM, the thin descending limb of Henle's loop and macula densa cells. After I/R, HA and CD44 staining appeared in C and OSOM at 12 h and persisted throughout the regenerative period, i.e. until day 7. Thereafter, they regressed but remained associated with remodeling areas. CD44 expression was found de novo on the apical pole of regenerating, not fully differentiated tubular cells and on some interstitial cells. It was prominent on all infiltrating neutrophils, as soon as 2 h post-I/R, and on 30% of the macrophages, including those in late HA-rich inflammatory granulomas. CD44 is probably involved in early leukocyte infiltration, in tubular regeneration, and in macrophage activity, while HA modifies the physico-chemical environment of interstitial and migrating cells. Based on its presence in remodeling areas, the HA-CD44 pair may be implicated in persistent postichemic inflammation as observed in chronic allograft nephropathy.

  17. Fabrication of tubular tissue constructs by centrifugal casting of cells suspended in an in situ crosslinkable hyaluronan-gelatin hydrogel.

    Science.gov (United States)

    Mironov, Vladimir; Kasyanov, Vladimir; Zheng Shu, Xiao; Eisenberg, Carol; Eisenberg, Leonard; Gonda, Steve; Trusk, Thomas; Markwald, Roger R; Prestwich, Glenn D

    2005-12-01

    Achieving the optimal cell density and desired cell distribution in scaffolds is a major goal of cell seeding technologies in tissue engineering. In order to reach this goal, a novel centrifugal casting technology was developed using in situ crosslinkable hyaluronan-based (HA) synthetic extracellular matrix (sECM). Living cells were suspended in a viscous solution of thiol-modified HA and thiol-modified gelatin, a polyethyleneglycol diacrylate crosslinker was added, and a hydrogel was formed during rotation. The tubular tissue constructs consisting of a densely packed cell layer were fabricated with the rotation device operating at 2000 rpm for 10 min. The majority of cells suspended in the HA mixture before rotation were located inside the layer after centrifugal casting. Cells survived the effect of the centrifugal forces experienced under the rotational regime employed. The volume cell density (65.6%) approached the maximal possible volume density based on theoretical sphere packing models. Thus, centrifugal casting allows the fabrication of tubular constructs with the desired redistribution, composition and thickness of cell layers that makes the maximum efficient use of available cells. Centrifugal casting in this sECM would enable rapid fabrication of tissue-engineered vascular grafts, as well as other tubular and planar tissue-engineered constructs.

  18. Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

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    Takabe, Piia, E-mail: piia.takabe@uef.fi [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Bart, Geneviève [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Ropponen, Antti [University of Eastern Finland, Institute of Clinical Medicine, 70211 Kuopio (Finland); Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland)

    2015-09-10

    Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma.

  19. Low molecular weight hyaluronan activates cytosolic phospholipase A2α and eicosanoid production in monocytes and macrophages.

    Science.gov (United States)

    Sokolowska, Milena; Chen, Li-Yuan; Eberlein, Michael; Martinez-Anton, Asuncion; Liu, Yueqin; Alsaaty, Sara; Qi, Hai-Yan; Logun, Carolea; Horton, Maureen; Shelhamer, James H

    2014-02-14

    Hyaluronan (HA) is the major glycosaminoglycan in the extracellular matrix. During inflammation, there is an increased breakdown of HA, resulting in the accumulation of low molecular weight (LMW) HA and activation of monocytes and macrophages. Eicosanoids, derived from the cytosolic phospholipase A2 group IVA (cPLA2α) activation, are potent lipid mediators also attributed to acute and chronic inflammation. The aim of this study was to determine the effect of LMW HA on cPLA2α activation, arachidonic acid (AA) release, and subsequent eicosanoid production and to examine the receptors and downstream mechanisms involved in these processes in monocytes and differently polarized macrophages. LMW HA was a potent stimulant of AA release in a time- and dose-dependent manner, induced cPLA2α, ERK1/2, p38, and JNK phosphorylation, as well as activated COX2 expression and prostaglandin (PG) E2 production in primary human monocytes, murine RAW 264.7, and wild-type bone marrow-derived macrophages. Specific cPLA2α inhibitor blocked HA-induced AA release and PGE2 production in all of these cells. Using CD44, TLR4, TLR2, MYD88, RHAMM or STAB2 siRNA-transfected macrophages and monocytes, we found that AA release, cPLA2α, ERK1/2, p38, and JNK phosphorylation, COX2 expression, and PGE2 production were activated by LMW HA through a TLR4/MYD88 pathway. Likewise, PGE2 production and COX2 expression were blocked in Tlr4(-/-) and Myd88(-/-) mice, but not in Cd44(-/-) mice, after LMW HA stimulation. Moreover, we demonstrated that LMW HA activated the M1 macrophage phenotype with the unique cPLA2α/COX2(high) and COX1/ALOX15/ALOX5/LTA4H(low) gene and PGE2/PGD2/15-HETE(high) and LXA4(low) eicosanoid profile. These findings reveal a novel link between HA-mediated inflammation and lipid metabolism.

  20. The HaDREB2 transcription factor enhances basal thermotolerance and longevity of seeds through functional interaction with HaHSFA9

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    Carranco Raúl

    2009-06-01

    Full Text Available Abstract Background Transcription factor HaDREB2 was identified in sunflower (Helianthus annuus L. as a drought-responsive element-binding factor 2 (DREB2 with unique properties. HaDREB2 and the sunflower Heat Shock Factor A9 (HaHSFA9 co-activated the Hahsp17.6G1 promoter in sunflower embryos. Both factors could be involved in transcriptional co-activation of additional small heat stress protein (sHSP promoters, and thus contribute to the HaHSFA9-mediated enhancement of longevity and basal thermotolerance of seeds. Results We found that overexpression of HaDREB2 in seeds did not enhance longevity. This was deduced from assays of basal thermotolerance and controlled seed-deterioration, which were performed with transgenic tobacco. Furthermore, the constitutive overexpression of HaDREB2 did not increase thermotolerance in seedlings or result in the accumulation of HSPs at normal growth temperatures. In contrast, when HaDREB2 and HaHSFA9 were conjointly overexpressed in seeds, we observed positive effects on seed longevity, beyond those observed with overexpression of HaHSFA9 alone. Such additional effects are accompanied by a subtle enhancement of the accumulation of subsets of sHSPs belonging to the CI and CII cytosolic classes. Conclusion Our results reveal the functional interdependency of HaDREB2 and HaHSFA9 in seeds. HaDREB2 differs from other previously characterized DREB2 factors in plants in terms of its unique functional interaction with the seed-specific HaHSFA9 factor. No functional interaction between HaDREB2 and HaHSFA9 was observed when both factors were conjointly overexpressed in vegetative tissues. We therefore suggest that additional, seed-specific factors, or protein modifications, could be required for the functional interaction between HaDREB2 and HaHSFA9.

  1. A prospective randomised controlled clinical trial comparing the efficacy of different molecular weight hyaluronan solutions in the treatment of knee osteoarthritis.

    Science.gov (United States)

    Kotevoglu, Nurdan; Iyibozkurt, Pinar Cakil; Hiz, Ozcan; Toktas, Hasan; Kuran, Banu

    2006-02-01

    Viscosupplementation consists of injecting exagenous hyaluronan (HA) into the synovial joints to restore the normal rheological environment which deteriorates severely in osteoarthritic (OA) joints. Efficacy might be related to the rheological properties and molecular weight (MW) of the hyaluronan preparations. This prospective, controlled, double-blind, randomised clinical trial was aimed at comparing the elastoviscous properties of a high molecular weight viscosupplement, hylan G-F 20, with that of a lower molecular weight hyaluronan product in order to determine the relationship of elastoviscosity to efficacy, alongside placebo, in the treatment of patients with knee OA. The results were analysed as a "completers" analysis with 59 patients. Primary outcome measures included the Western Ontario and Mc Master Universities' Osteoarthritis Index (WOMAC) for pain, stiffness and function scores, and patient and physician global assessments (0-100 scale). For patient (PGA) and physician global assessments (PhGA), the 0-100 scale was used, with 100 being the worst. Follow-up assessments were made at intervals of 1, 3 and 6 months after the first injection. Local adverse events, such as transient pain at the injection site or warm knee lasting for one night, were recorded in two patients (3%). In all groups, the WOMAC pain score exhibited a significant difference from the baseline value; neither treatment group was significantly different from the placebo group, but total pain score was significantly better than baseline for both of the HA groups at the end of 6 months (p < 0.05). Improvement in WOMAC physical function score favoured both sodium hyaluronate and hylan G-F 20 after the first month, and remained significant until the end of 6 months (p < 0.01). In the placebo group, the physical function scores became worse after the end of the 1st month; the scores at the end of 6 months were no different from those at the beginning. The WOMAC stiffness scores of both of

  2. The role of interleukin-10 and hyaluronan in murine fetal fibroblast function in vitro: implications for recapitulating fetal regenerative wound healing.

    Science.gov (United States)

    Balaji, Swathi; King, Alice; Marsh, Emily; LeSaint, Maria; Bhattacharya, Sukanta S; Han, Nathaniel; Dhamija, Yashu; Ranjan, Rajeev; Le, Louis D; Bollyky, Paul L; Crombleholme, Timothy M; Keswani, Sundeep G

    2015-01-01

    Mid-gestation fetal cutaneous wounds heal scarlessly and this has been attributed in part to abundant hyaluronan (HA) in the extracellular matrix (ECM) and a unique fibroblast phenotype. We recently reported a novel role for interleukin 10 (IL-10) as a regulator of HA synthesis in the fetal ECM, as well as the ability of the fetal fibroblast to produce an HA-rich pericellular matrix (PCM). We hypothesized that IL-10-mediated HA synthesis was essential to the fetal fibroblast functional phenotype and, moreover, that this phenotype could be recapitulated in adult fibroblasts via supplementation with IL-10 via an HA dependent process. To evaluate the differences in functional profile, we compared metabolism (MTS assay), apoptosis (caspase-3 staining), migration (scratch wound assay) and invasion (transwell assay) between C57Bl/6J murine fetal (E14.5) and adult (8 weeks) fibroblasts. We found that fetal fibroblasts have lower rates of metabolism and apoptosis, and an increased ability to migrate and invade compared to adult fibroblasts, and that these effects were dependent on IL-10 and HA synthase activity. Further, addition of IL-10 to adult fibroblasts resulted in increased fibroblast migration and invasion and recapitulated the fetal phenotype in an HA-dependent manner. Our data demonstrates the functional differences between fetal and adult fibroblasts, and that IL-10 mediated HA synthesis is essential for the fetal fibroblasts' enhanced invasion and migration properties. Moreover, IL-10 via an HA-dependent mechanism can recapitulate this aspect of the fetal phenotype in adult fibroblasts, suggesting a novel mechanism of IL-10 in regenerative wound healing.

  3. The role of interleukin-10 and hyaluronan in murine fetal fibroblast function in vitro: implications for recapitulating fetal regenerative wound healing.

    Directory of Open Access Journals (Sweden)

    Swathi Balaji

    Full Text Available Mid-gestation fetal cutaneous wounds heal scarlessly and this has been attributed in part to abundant hyaluronan (HA in the extracellular matrix (ECM and a unique fibroblast phenotype. We recently reported a novel role for interleukin 10 (IL-10 as a regulator of HA synthesis in the fetal ECM, as well as the ability of the fetal fibroblast to produce an HA-rich pericellular matrix (PCM. We hypothesized that IL-10-mediated HA synthesis was essential to the fetal fibroblast functional phenotype and, moreover, that this phenotype could be recapitulated in adult fibroblasts via supplementation with IL-10 via an HA dependent process.To evaluate the differences in functional profile, we compared metabolism (MTS assay, apoptosis (caspase-3 staining, migration (scratch wound assay and invasion (transwell assay between C57Bl/6J murine fetal (E14.5 and adult (8 weeks fibroblasts. We found that fetal fibroblasts have lower rates of metabolism and apoptosis, and an increased ability to migrate and invade compared to adult fibroblasts, and that these effects were dependent on IL-10 and HA synthase activity. Further, addition of IL-10 to adult fibroblasts resulted in increased fibroblast migration and invasion and recapitulated the fetal phenotype in an HA-dependent manner.Our data demonstrates the functional differences between fetal and adult fibroblasts, and that IL-10 mediated HA synthesis is essential for the fetal fibroblasts' enhanced invasion and migration properties. Moreover, IL-10 via an HA-dependent mechanism can recapitulate this aspect of the fetal phenotype in adult fibroblasts, suggesting a novel mechanism of IL-10 in regenerative wound healing.

  4. Preparation and application of hydroxyapatite(HA) nanoparticles/NR2B-siRNA complex

    Institute of Scientific and Technical Information of China (English)

    YANG Hui; HUANG Dong; ZHU Shai-hong; YAN Xue-bin; GU Yong-hong; YAN Hui; WU Li-xiang

    2008-01-01

    Hydroxyapatite(HA) nanoparticles were prepared by coprecipitation-hydrothermal synthesis and their exosyndrome was estimated via transmission electron microscopy. Agarose gel electrophoresis and ultraviolet spectrophotometry were used to evaluate the ability of HA to bind NR2B-siRNA at different pH values and at different HA-NR2B-siRNA ratios. And the stability of the complex in saline was also evaluated. The effect of HA/NR2B-siRNA complex on chronic inflammatory pain was evaluated in vivo in mice. Transmission electron microscopy(TEM) reveals that HA nanoparticles are thin strips or short rod in shape and the one-dimensional particle size of HA nanoparticles is 40-50 nm. Under the acid or neutral condition, the Zeta potential of HA is positive; nanoparticles can completely bind NR2B-siRNA when the HA:NR2B-siRNA ratio is at or larger than 35-1; while under the alkaline condition, the affinity of HA to NR2B-siRNA is rather weak. HA/NR2B-siRNA complex is not dissociated when being resuspended in saline. The nociception of the tonic phase induced by formalin is significantly reduced in the HA/NR2B-siRNA treated mice as compared with the controls. Therefore, HA may be a new siRNA nano-vector material.

  5. [Hyaluronic acid (hyaluronan) levels in pathological human saphenous veins. Effects of procyanidol oligomers].

    Science.gov (United States)

    Drubaix, I; Maraval, M; Robert, L; Robert, A M

    1997-01-01

    We investigated the hyaluronan content in the pathologic human venous wall using an ELSA assay with hyaluronectin according to the method of Delpech et al. The mean hyaluronan content in the 74 fragments from 12 venous walls studied was 596 +/- 528 ng/mg dry weight. These 12 venous walls could be separated in 3 distinct groups according to their hyaluronan content, low (277 +/- 141 ng/mg dry weight), moderate (552 +/- 361 ng/m dry weight) or high (1299 +/- 568 ng/mg dry weight). The differences between these groups are significant (p < 0.001). The presence of a veino-lymphatic oedema was generally associated with a high hyaluronan level (in 65% of cases). The 3H-glucosamine incorporation in cultured venous wall explants showed a 35% increase (p < 0.002) in varicosis as compared with the non or less modified segments of the vein and a 29% (p < 0.001) increase in presence of a veino-lymphatic oedema. The addition of 1 mg/ml of PCO (Procyanidolic Oligomers) to the culture media induced near to 20% decrease of the 3H-glucosamine incorporation and a 34% decrease of the hyaluronan content. Our results confirm the role of local overproduction of hyaluronan in the establishment of oedema and the potential effect of PCO to counteract it.

  6. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

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    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  7. Selective hyaluronan-CD44 signaling promotes miRNA-21 expression and interacts with vitamin D function during cutaneous squamous cell carcinomas progression following UV irradiation

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    Lilly YW Bourguignon

    2015-05-01

    Full Text Available Hyaluronan (HA, the major extracellular matrix component, is often anchored to CD44 isoforms, a family of structurally/functionally important cell surface receptors. Our recent results indicate that UV irradiation (UVR-induced cutaneous squamous cell carcinomas (SCC overexpress a variety of CD44 variant isoforms (CD44v, with different CD44v isoforms appear to confer malignant SCC properties. UVR also stimulates HA degradation in epidermal keratinocytes. Both large HA polymers and their UVR-induced catabolic products (small HA selectively activate CD44 isoform-mediated cellular signaling in normal keratinocytes and SCC cells, with all of the downstream processes being mediated by RhoGTPases (e.g., RhoA and Rac1. Importantly, we found that the hormonally active form of vitamin D (1,25(OH2D3 not only prevents the UVR-induced small HA activation of abnormal keratinocyte behavior and SCC progression, but also enhances large HA stimulation of normal keratinocyte activities and epidermal function(s. Furthermore, we found that HA and its UVR-induced catabolic products (e.g., large and small HA selectively activate CD44-mediated Rac and RhoA signaling. Specifically, large HA-CD44 interaction promotes Rac/PKNγ-dependent normal keratinocyte differentiation, DNA repair and keratinocyte survival. Conversely, small HA-CD44v isoform interaction stimulates RhoA/ROK-dependent NFκB signaling and microRNA-21 (miR-21 production, leading to inflammation, proliferation (following acute UVR response and SCC progression (following chronic UVR exposure. Active vitamin D inhibits small HA-CD44v-mediated RhoA/ROK signaling and SCC progression; and it also enhances large HA-CD44-mediated differentiation, DNA repair and normal epidermal function. Selective applications of large HA and vitamin D will be used to improve the UVR-induced HA (small vs. large HA-CD44 isoform interaction with RhoGTPase signaling and skin inflammation as a potential therapeutic treatment for skin

  8. PLLA-HA composites: Synthesis and characterization

    Science.gov (United States)

    Gonzalez, Gema; Albano, Carmen; Palacios, Jordana

    2012-07-01

    A composite based on PLLA -HA was prepared by the solvent casting technique and characterized. An interaction between the polymer matrix and HA through the carbonyl and phosphate groups was obtained by FTIR . The several thermal transitions of PLLA were evaluated by DSC: the glass transition, crystallization, cold crystallization, melt-recrystallization and melting. The addition of HA to PLLA matrix increases its glass transition temperature and no major changes on the melting temperature and crystallinity were observed. The PLLA-HA composite showed better thermal stability than the neat polymer. The introduction of the nano-HA particles increased the decomposition temperature and the activation energy retarding the decomposition process.

  9. Preventing effects of joint contracture by high molecular weight hyaluronan injections in a rat immobilized knee model.

    Science.gov (United States)

    Kanazawa, Kenji; Hagiwara, Yoshihiro; Tsuchiya, Masahiro; Yabe, Yutaka; Sonofuchi, Kazuaki; Koide, Masashi; Sekiguchi, Takuya; Itaya, Nobuyuki; Ando, Akira; Saijo, Yoshifumi; Itoi, Eiji

    2015-01-01

    To elucidate preventive effects of high molecular weight hyaluronan (HMWHA) on the joint capsule of immobilized knees in rats. Unilateral knee joints of rats were immobilized with an internal fixator. Either 50 μl of HMWHA (Im-HA group) or 50 μl of saline (control group) was administered intra-articularly once a week after surgery. Sagittal sections were prepared from the medial midcondylar region of the knee joints and assessed by histological, histomorphometric, and immunohistochemical methods. Gene expressions related to inflammation, fibrotic conditions, and hypoxia were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Tissue elasticity of the capsule from both groups was examined using a scanning acoustic microscope (SAM). CD68 positive cells decreased in adhesion areas of the synovial membrane after 1 week in both groups. The length of the superficial layer in the synovial membrane of the Im-HA group was significantly longer than those in the control group over a period of 4 to 8 weeks with significantly small numbers of CD68 positive cells. The gene expressions of IL-6, IL-1β, TGF-β, CTGF, COL1a1, COL3a1, SPARC, and HIF1-α were significantly lower in the Im-HA group compared to those in the control group. The sound speed of the anterior and posterior synovial membrane increased significantly (a reduction in elasticity) in the control group compared to those in the Im-HA group during weeks 1 to 4. This study demonstrated that HMWHA injections suppressed inflammatory, fibrotic, and hypoxic conditions observed in the immobilized joint capsule.

  10. Semi-permeable membrane retention of synovial fluid lubricants hyaluronan and proteoglycan 4 for a biomimetic bioreactor.

    Science.gov (United States)

    Blewis, Megan E; Lao, Brian J; Jadin, Kyle D; McCarty, William J; Bugbee, William D; Firestein, Gary S; Sah, Robert L

    2010-05-01

    Synovial fluid (SF) contains lubricant macromolecules, hyaluronan (HA), and proteoglycan 4 (PRG4). The synovium not only contributes lubricants to SF through secretion by synoviocyte lining cells, but also concentrates lubricants in SF due to its semi-permeable nature. A membrane that recapitulates these synovium functions may be useful in a bioreactor system for generating a bioengineered fluid (BF) similar to native SF. The objectives were to analyze expanded polytetrafluoroethylene membranes with pore sizes of 50 nm, 90 nm, 170 nm, and 3 microm in terms of (1) HA and PRG4 secretion rates by adherent synoviocytes, and (2) the extent of HA and PRG4 retention with or without synoviocytes adherent on the membrane. Experiment 1: Synoviocytes were cultured on tissue culture (TC) plastic or membranes +/- IL-1beta + TGF-beta1 + TNF-alpha, a cytokine combination that stimulates lubricant synthesis. HA and PRG4 secretion rates were assessed by analysis of medium. Experiment 2: Bioreactors were fabricated to provide a BF compartment enclosed by membranes +/- adherent synoviocytes, and an external compartment of nutrient fluid (NF). A solution with HA (1 mg/mL, MW ranging from 30 to 4,000 kDa) or PRG4 (50 microg/mL) was added to the BF compartment, and HA and PRG4 loss into the NF compartment after 2, 8, and 24 h was determined. Lubricant loss kinetics were analyzed to estimate membrane permeability. Experiment 1: Cytokine-regulated HA and PRG4 secretion rates on membranes were comparable to those on TC plastic. Experiment 2: Transport of HA and PRG4 across membranes was lowest with 50 nm membranes and highest with 3 microm membranes, and transport of high MW HA was decreased by adherent synoviocytes (for 50 and 90 nm membranes). The permeability to HA mixtures for 50 nm membranes was approximately 20 x 10(-8) cm/s (- cells) and approximately 5 x 10(-8) cm/s (+ cells), for 90 nm membranes was approximately 35 x 10(-8) cm/s (- cells) and approximately 19 x 10(-8) cm

  11. Hyaluronan synthases (HAS1-3 and hyaluronidases (HYAL1-2 in the accumulation of hyaluronan in endometrioid endometrial carcinoma

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    Kosma Veli-Matti

    2010-09-01

    Full Text Available Abstract Background Hyaluronan accumulation correlates with the degree of malignancy in many solid tumor types, including malignant endometrial carcinomas. To elucidate the mechanism of hyaluronan accumulation, we examined the expression levels of the hyaluronan synthases (HAS1, HAS2 and HAS3 and hyaluronidases (HYAL1 and HYAL2, and correlated them with hyaluronan content and HAS1-3 immunoreactivity. Methods A total of 35 endometrial tissue biopsies from 35 patients, including proliferative and secretory endometrium (n = 10, post-menopausal proliferative endometrium (n = 5, complex atypical hyperplasia (n = 4, grade 1 (n = 8 and grade 2 + 3 (n = 8 endometrioid adenocarcinomas were divided for gene expression by real-time RT-PCR, and paraffin embedded blocks for hyaluronan and HAS1-3 cytochemistry. Results The mRNA levels of HAS1-3 were not consistently changed, while the immunoreactivity of all HAS proteins was increased in the cancer epithelium. Interestingly, HAS3 mRNA, but not HAS3 immunoreactivity, was increased in post-menopausal endometrium compared to normal endometrium (p = 0.003. The median of HYAL1 mRNA was 10-fold and 15-fold lower in both grade 1 and grade 2+3 endometrioid endometrial cancers, as compared to normal endometrium (p = 0.004-0.006, and post-menopausal endometrium (p = 0.002, respectively. HYAL2 mRNA was also reduced in cancer (p = 0.02 and correlated with HYAL1 (r = 0.8, p = 0.0001. There was an inverse correlation between HYAL1 mRNA and the epithelial hyaluronan staining intensity (r = -0.6; P = 0.001. Conclusion The results indicated that HYAL1 and HYAL2 were coexpressed and significantly downregulated in endometrioid endometrial cancer and correlated with the accumulation of hyaluronan. While immunoreactivity for HASs increased in the cancer cells, tumor mRNA levels for HASs were not changed, suggesting that reduced turnover of HAS protein may also have contributed to the accumulation of hyaluronan.

  12. Comparison of Peritendinous Hyaluronan Injections Versus Extracorporeal Shock Wave Therapy in the Treatment of Painful Achilles' Tendinopathy: A Randomized Clinical Efficacy and Safety Study.

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    Lynen, Nils; De Vroey, Thierry; Spiegel, Imke; Van Ongeval, Frederik; Hendrickx, Niels-Jan; Stassijns, Gaëtane

    2017-01-01

    To compare the safety and efficacy of hyaluronan (HA) injections with standard extracorporeal shock wave therapy (ESWT) in the treatment of painful midportion Achilles' tendinopathy. Multinational, prospective, randomized controlled, blinded-observer trial. Ambulatory care. Adults (N=62) with Achilles' midportion tendinopathy for ≥6 weeks and a pain score of at least 40mm (Huskisson visual analog scale [VAS], 100mm) were randomized, and 59 were analyzed in the intention-to-treat data set. There were no withdrawals because of adverse effects. Two peritendinous HA injections versus 3 ESWT applications at weekly intervals. Primary efficacy criterion was changed from the Victorian Institute of Sports Assessment-Achilles' questionnaire (VISA-A) score to the percent change in pain (VAS) at 3 months posttreatment, compared with baseline values. Main secondary parameters were VISA-A, Clinical Global Impression (CGI), and clinical parameters. HA treatment provided a clinically relevant improvement in Achilles' midportion tendinopathy. A large superiority of the HA group, compared with ESWT application, was observed for percent change in pain (VAS), and this superiority was proven to be statistically significant (Mann-Whitney statistic [MW]=.7507 with P=.0030 lower than required α=.025 significance level 1-sided; Mann-Whitney U test) at 3 months posttreatment. Similar findings for HA were also observed at 4 weeks (MW=.6425, P=.0304) and 6 months (MW=.7172, P=.0018). Advantage of HA treatment was confirmed by VISA-A questionnaire, CGI, and clinical parameters. Ten adverse events, 4 in the HA group and 6 in the ESWT group, were reported, but none were classified as serious. Two peritendinous HA injections showed greater treatment success in Achilles' midportion tendinopathy compared with standard ESWT. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  13. Rheological and structural characterization of HA/PVA-SbQ composites film-forming solutions and resulting films as affected by UV irradiation time.

    Science.gov (United States)

    Bai, Huiyu; Sun, Yunlong; Xu, Jing; Dong, Weifu; Liu, Xiaoya

    2015-01-22

    Hyaluronan (HA)/poly (vinyl alcohol) bearing styrylpyridinium groups (PVA-SbQ) composites film-forming solutions were prepared by a negatively charged HA and an oppositely charged PVA-SbQ. The rheological properties and structural characterization of HA/PVA-SbQ composites in aqueous solution were investigated. Zeta potential measurements and TEM were utilized to explore the formation of HA/PVA-SbQ complex micelles in aqueous solution. UV spectra and DLS experiments confirmed that the micelles are photo-crosslinkable. HA/PVA-SbQ composites films were prepared by a casting method. The microstructure and properties of the film were analyzed by SEM, optical transmittance, DSC, XRD and tensile testing. The crosslinked HA/PVA-SbQ composites films exhibited higher UV light shielding and visible light transparency and better mechanical and water vapor barrier properties as well as thermal stability than the uncrosslinked HA/PVA-SbQ composites films, indicating the formation of three-dimensional network structure. This work provided a good way for increasing the mechanical, thermal, water vapor barrier, and optical properties of HA materials for the packaging material.

  14. Growth behaviour and mechanical properties of PLL/HA multilayer films studied by AFM.

    Science.gov (United States)

    Uzüm, Cagri; Hellwig, Johannes; Madaboosi, Narayanan; Volodkin, Dmitry; von Klitzing, Regine

    2012-01-01

    Scanning- and colloidal-probe atomic force microscopy were used to study the mechanical properties of poly(L-lysine)/hyaluronan (PLL/HA)(n) films as a function of indentation velocity and the number of polymer deposition steps n. The film thickness was determined by two independent AFM-based methods: scratch-and-scan and newly developed full-indentation. The advantages and disadvantages of both methods are highlighted, and error minimization techniques in elasticity measurements are addressed. It was found that the film thickness increases linearly with the bilayer number n, ranging between 400 and 7500 nm for n = 12 and 96, respectively. The apparent Young's modulus E ranges between 15 and 40 kPa and does not depend on the indenter size or the film bilayer number n. Stress relaxation measurements show that PLL/HA films have a viscoelastic behaviour, regardless of their thickness. If indentation is performed several times at the same lateral position on the film, a viscous/plastic deformation takes place.

  15. Cell density-dependent stimulation of PAI-1 and hyaluronan synthesis by TGF-β in orbital fibroblasts.

    Science.gov (United States)

    Galgoczi, Erika; Jeney, Florence; Gazdag, Annamaria; Erdei, Annamaria; Katko, Monika; Nagy, Domonkos M; Ujhelyi, Bernadett; Steiber, Zita; Gyory, Ferenc; Berta, Eszter; Nagy, Endre V

    2016-05-01

    During the course of Graves' orbitopathy (GO), orbital fibroblasts are exposed to factors that lead to proliferation and extracellular matrix (ECM) overproduction. Increased levels of tissue plasminogen activator inhibitor type 1 (PAI-1 (SERPINE1)) might promote the accumulation of ECM components. PAI-1 expression is regulated by cell density and various cytokines and growth factors including transforming growth factorβ(TGF-β). We examined the effects of increasing cell densities and TGF-β on orbital fibroblasts obtained from GO patients and controls. Responses were evaluated by the measurement of proliferation, PAI-1 expression, and ECM production. There was an inverse correlation between cell density and the per cell production of PAI-1. GO orbital, normal orbital, and dermal fibroblasts behaved similarly in this respect. Proliferation rate also declined with increasing cell densities. Hyaluronan (HA) production was constant throughout the cell densities tested in all cell lines. In both GO and normal orbital fibroblasts, but not in dermal fibroblasts, TGF-β stimulated PAI-1 production in a cell density-dependent manner, reaching up to a five-fold increase above baseline. This has been accompanied by increased HA secretion and pericellular HA levels at high cell densities. Increasing cell density is a negative regulator of proliferation and PAI-1 secretion both in normal and GO orbital fibroblasts; these negative regulatory effects are partially reversed in the presence of TGF-β. Cell density-dependent regulation of PAI-1 expression in the orbit, together with the local cytokine environment, may have a regulatory role in the turnover of the orbital ECM and may contribute to the expansion of orbital soft tissue in GO.

  16. Laser treatment of plasma sprayed HA coatings

    NARCIS (Netherlands)

    Khor, KA; Vreeling, A; Dong, ZL; Cheang, P

    1999-01-01

    Laser treatment was conducted on plasma sprayed hydroxyapatite (HA) coatings using a Nd-YAG pulse laser. Various laser parameters were investigated. The results showed that the HA surface melted when an energy level of greater than or equal to 2 J and a spot size of 2 mm was employed during continuo

  17. ha õhtu seltskonnalaud / Kaire Nurk

    Index Scriptorium Estoniae

    Nurk, Kaire, 1960-

    2005-01-01

    ha õhtusöömaaja teemast kunstis. Saksa kunstiajaloolase Horst Schwebeli poolt Leonardo da Vinci "Püha õhtusöömaaja" XX sajandi "töötlustes" välja toodud poliitilise agitatsiooni ja ühisest probleemist haaratud seltskonna kujutiste suunast. Laua kujutisest kunstis

  18. ha õhtu seltskonnalaud / Kaire Nurk

    Index Scriptorium Estoniae

    Nurk, Kaire, 1960-

    2005-01-01

    ha õhtusöömaaja teemast kunstis. Saksa kunstiajaloolase Horst Schwebeli poolt Leonardo da Vinci "Püha õhtusöömaaja" XX sajandi "töötlustes" välja toodud poliitilise agitatsiooni ja ühisest probleemist haaratud seltskonna kujutiste suunast. Laua kujutisest kunstis

  19. Laser treatment of plasma sprayed HA coatings

    NARCIS (Netherlands)

    Khor, KA; Vreeling, A; Dong, ZL; Cheang, P

    1999-01-01

    Laser treatment was conducted on plasma sprayed hydroxyapatite (HA) coatings using a Nd-YAG pulse laser. Various laser parameters were investigated. The results showed that the HA surface melted when an energy level of greater than or equal to 2 J and a spot size of 2 mm was employed during continuo

  20. Modulation of Hyaluronan Synthesis by the Interaction between Mesenchymal Stem Cells and Osteoarthritic Chondrocytes

    Directory of Open Access Journals (Sweden)

    Eliane Antonioli

    2015-01-01

    Full Text Available Bone marrow mesenchymal stem cells (BM-MSCs are considered a good source for cellular therapy in cartilage repair. But, their potential to repair the extracellular matrix, in an osteoarthritic environment, is still controversial. In osteoarthritis (OA, anti-inflammatory action and extracellular matrix production are important steps for cartilage healing. This study examined the interaction of BM-MSC and OA-chondrocyte on the production of hyaluronan and inflammatory cytokines in a Transwell system. We compared cocultured BM-MSCs and OA-chondrocytes with the individually cultured controls (monocultures. There was a decrease in BM-MSCs cell count in coculture with OA-chondrocytes when compared to BM-MSCs alone. In monoculture, BM-MSCs produced higher amounts of hyaluronan than OA-chondrocytes and coculture of BM-MSCs with OA-chondrocytes increased hyaluronan production per cell. Hyaluronan synthase-1 mRNA expression was upregulated in BM-MSCs after coculture with OA-chondrocytes, whereas hyaluronidase-1 was downregulated. After coculture, lower IL-6 levels were detected in BM-MSCs compared with OA-chondrocytes. These results indicate that, in response to coculture with OA-chondrocytes, BM-MSCs change their behavior by increasing production of hyaluronan and decreasing inflammatory cytokines. Our results indicate that BM-MSCs per se could be a potential tool for OA regenerative therapy, exerting short-term effects on the local microenvironment even when cell:cell contact is not occurring.

  1. Enantiomers of HA-966 (3-amino-1-hydroxypyrrolid-2-one) exhibit distinct central nervous system effects: (+)-HA-966 is a selective glycine/N-methyl-D-aspartate receptor antagonist, but (-)-HA-966 is a potent gamma-butyrolactone-like sedative

    Energy Technology Data Exchange (ETDEWEB)

    Singh, L.; Donald, A.E.; Foster, A.C.; Hutson, P.H.; Iversen, L.L.; Iversen, S.D.; Kemp, J.A.; Leeson, P.D.; Marshall, G.R.; Oles, R.J.; Priestley, T.; Thorn, L.; Tricklebank, M.D.; Vass, C.A.; Williams, B.J. (Merck Sharp and Dohme Research Labs., Essex (England))

    1990-01-01

    The antagonist effect of {+-}-3-amino-1-hydroxypyrrolid-2-one (HA-966) at the N-methyl-D-aspartate (NMDA) receptor occurs through a selective interaction with the glycine modulatory site within the receptor complex. When the enantiomers of {+-}-HA-966 were resolved, the (R)-(+)-enantiomer was found to be a selective glycine/NMDA receptor antagonist, a property that accounts for its anticonvulsant activity in vivo. In contrast, the (S)-(-)-enantiomer was only weakly active as an NMDA-receptor antagonist, but nevertheless it possessed a marked sedative and muscle relaxant action in vivo. In radioligand binding experiments, (+)-HA-966 inhibited strychnine-insensitive ({sup 3}H)glycine binding to rat cerebral cortex synaptic membranes with an IC{sub 50} of 12.5 {mu}M, whereas (-)-HA-966 had an IC{sub 50} value of 339 {mu}M. In mice, (+)-HA-966 antagonized sound and N-methyl-DL-aspartic acid (NMDLA)-induced seizures. The coadministration of D-serine dose-dependently antagonized the anticonvulsant effect of a submaximal dose of (+)-HA-966 against NMDLA-induced seizures. The sedative/ataxic effect of racemic HA-966 was mainly attributable to the (-)-enantiomer. It is suggested that, as in the case of the sedative {gamma}-butyrolactone, disruption of striatal dopaminergic mechanisms may be responsible for this action.

  2. Single step synthesis and characterization of thermoresponsive hyaluronan hydrogels.

    Science.gov (United States)

    D'Este, Matteo; Alini, Mauro; Eglin, David

    2012-10-15

    An efficient and scale-up ready single-step synthesis for the conjugation of thermoresponsive polymers to hyaluronic acid (HA) was established. Jeffamines(®) (JFM) and poly(N-isopropylacrylamide) (PNIPAM) were grafted to HA via direct amidation mediated by 1,1'-carbonyldiimidazole activation. The temperature-induced gelation of the semi-synthetic co-polymers was characterized by rheology as a function of the temperature and by differential scanning calorimetry (DSC). A HA-JFM conjugate with sol-gel transition in a physiologically relevant temperature range was identified. The grafting of PNIPAM resulted in the drastic change of the main rheological properties of native HA, revealing the hydrophobic non-covalent nature of the interactions between the thermoresponsive brushes in the gel state. Owing to the reversibility of these interactions and the sharpness of the transition, the HA-PNIPAM conjugates are suitable candidates for the incorporation of drugs, cells or ceramic materials for different biomedical applications.

  3. Hyaluronan scaffold supports osteogenic differentiation of bone marrow concentrate cells.

    Science.gov (United States)

    Cavallo, C; Desando, G; Ferrari, A; Zini, N; Mariani, E; Grigolo, B

    2016-01-01

    Osteochondral lesions are considered a challenge for orthopedic surgeons. Currently, the treatments available are often unsatisfactory and unable to stimulate tissue regeneration. Tissue engineering offers a new therapeutic strategy, taking into account the role exerted by cells, biomaterial and growth factors in restoring tissue damage. In this light, Mesenchymal Stem Cells (MSCs) have been indicated as a fascinating tool for regenerative medicine thanks to their ability to differentiate into bone, cartilage and adipose tissue. However, in vitro-cultivation of MSCs could be associated with some risks such as de-differentiation/reprogramming, infection and contaminations of the cells. To overcome these shortcomings, a new approach is represented by the use of Bone Marrow Concentrate (BMC), that could allow the delivery of cells surrounded by their microenvironment in injured tissue. For this purpose, cells require a tridimensional scaffold that can support their adhesion, proliferation and differentiation. This study is focused on the potentiality of BMC seeded onto a hyaluronan-based scaffold (Hyaff-11) to differentiate into osteogenic lineage. This process depends on the specific interaction between cells derived from bone marrow (surrounded by their niche) and scaffold, that create an environment able to support the regeneration of damaged tissue. The data obtained from the present study demonstrate that BMC grown onto Hyaff-11 are able to differentiate toward osteogenic sense, producing specific osteogenic genes and matrix proteins.

  4. Improvement of the Digestibility of Sulfated Hyaluronans by Bovine Testicular Hyaluronidase: A UV Spectroscopic and Mass Spectrometric Study

    Directory of Open Access Journals (Sweden)

    Katharina Lemmnitzer

    2014-01-01

    Full Text Available Glycosaminoglycans (GAGs such as hyaluronan (HA and chondroitin sulfate (CS are important, natural polysaccharides which occur in biological (connective tissues and have various biotechnological and medical applications. Additionally, there is increasing evidence that chemically (oversulfated GAGs possess promising properties and are useful as implant coatings. Unfortunately, a detailed characterization of these GAGs is challenging: although mass spectrometry (MS is one of the most powerful tools to elucidate the structures of (polysaccharides, MS is not applicable to high mass polysaccharides, but characteristic oligosaccharides are needed. These oligosaccharides are normally generated by enzymatic digestion. However, chemically modified (particularly sulfated GAGs are extremely refractive to enzymatic digestion. This study focuses on the investigation of the digestibility of GAGs with different degrees of sulfation by bovine testicular hyaluronidase (BTH. It will be shown by using an adapted spectrophotometric assay that all investigated GAGs can be basically digested if the reaction conditions are carefully adjusted. However, the oligosaccharide yield correlates reciprocally with the number of sulfate residues per polymer repeating unit. Finally, matrix-laser desorption and ionization (MALDI MS will be used to study the released oligosaccharides and their sulfation patterns.

  5. Hyaluronan molecular weight is controlled by UDP-N-acetylglucosamine concentration in Streptococcus zooepidemicus.

    Science.gov (United States)

    Chen, Wendy Yiting; Marcellin, Esteban; Hung, Jacky; Nielsen, Lars Keld

    2009-07-03

    The molecular weight of hyaluronan is important for its rheological and biological function. The molecular mechanisms underlying chain termination and hence molecular weight control remain poorly understood, not only for hyaluronan synthases but also for other beta-polysaccharide synthases, e.g. cellulose, chitin, and 1,3-betaglucan synthases. In this work, we manipulated metabolite concentrations in the hyaluronan pathway by overexpressing the five genes of the hyaluronan synthesis operon in Streptococcus equi subsp. zooepidemicus. Overexpression of genes involved in UDP-glucuronic acid biosynthesis decreased molecular weight, whereas overexpression of genes involved in UDP-N-acetylglucosamine biosynthesis increased molecular weight. The highest molecular mass observed was at 3.4 +/- 0.1 MDa twice that observed in the wild-type strain, 1.8 +/- 0.1 MDa. The data indicate that (a) high molecular weight is achieved when an appropriate balance of UDP-N-acetylglucosamine and UDP-glucuronic acid is achieved, (b) UDP-N-acetylglucosamine exerts the dominant effect on molecular weight, and (c) the wild-type strain has suboptimal levels of UDP-N-acetylglucosamine. Consistent herewith molecular weight correlated strongly (rho = 0.84, p = 3 x 10(-5)) with the concentration of UDP-N-acetylglucosamine. Data presented in this paper represent the first model for hyaluronan molecular weight control based on the concentration of activated sugar precursors. These results can be used to engineer strains producing high molecular weight hyaluronan and may provide insight into similar polymerization mechanisms in other polysaccharides.

  6. A novel thiol-modified hyaluronan and elastin-like polypetide composite material for tissue engineering of the nucleus pulposus of the intervertebral disc.

    Science.gov (United States)

    Moss, Isaac L; Gordon, Lyle; Woodhouse, Kimberly A; Whyne, Cari M; Yee, Albert J M

    2011-06-01

    Biomechanical, in vitro, and initial in vivo evaluation of a thiol-modified hyaluronan (TM-HA) and elastin-like polypeptide (ELP) composite hydrogel for nucleus pulposus (NP) tissue engineering. To investigate the utility of a TM-HA and ELP composite material as a potential tissue-engineering scaffold to reconstitute the NP in early degenerative disc disease (DDD) on the basis of both biomechanical and biologic parameters. DDD is a common ailment with enormous medical, psychosocial, and economic ramifications. Only end-stage surgical therapies are currently widely available. A less invasive, early stage therapy may provide a clinically relevant treatment option. TM-HA and ELP were combined in various concentrations and cross-linked using poly (ethylene glycol) diacrylate. Resulting materials were evaluated biomechanically using confined compression to determine biphasic material properties. In vitro cell culture with human intervertebral disc (IVD) cells seeded within TM-HA/ELP scaffolds was analyzed for cell viability and phenotype. The hydrogels' materials were evaluated in an established New Zealand White (NZW) rabbit model of DDD. The addition of ELP to TM-HA-based hydrogels resulted in a stiffer construct, which is less stiff than native NP but has time-dependant loading characteristics that may be desirable when injected into the IVD. In vitro experiments demonstrated 70% cell viability at 3 weeks with apparent maintenance of phenotype on the basis of morphologic and immunohistochemical data. The addition of ELP had a positive desirable biomechanical effect but did not have a significant positive or negative biologic effect on cell activity. The in vivo feasibility study demonstrated favorable material characteristics and biocompatibility for application as a minimally invasive injectable NP supplement. TM-HA-based hydrogels provide a hospitable environment for human IVD cells and have material characteristics, particularly when supplemented with ELPs that

  7. High-resolution crystal structure of HA33 of botulinum neurotoxin type B progenitor toxin complex

    Science.gov (United States)

    Lee, Kwangkook; Lam, Kwok-Ho; Kruel, Anna Magdalena; Perry, Kay; Rummel, Andreas; Jin, Rongsheng

    2014-01-01

    Botulinum neurotoxins (BoNTs) are produced as progenitor toxin complexes (PTCs) by Clostridium botulinum. The PTCs are composed of BoNT and non-toxic neurotoxin-associated proteins (NAPs), which serve to protect and deliver BoNT through the gastrointestinal tract in food borne botulism. HA33 is a key NAP component that specifically recognizes host carbohydrates and helps enrich PTC on the intestinal lumen preceding its transport across the epithelial barriers. Here, we report the crystal structure of HA33 of type B PTC (HA33/B) in complex with lactose at 1.46 Å resolution. The structural comparisons among HA33 of serotypes A–D reveal two different HA33–glycan interaction modes. The glycan-binding pockets on HA33/A and B are more suitable to recognize galactose-containing glycans in comparison to the equivalent sites on HA33/C and D. On the contrary, HA33/C and D could potentially recognize Neu5Ac as an independent receptor, whereas HA33/A and B do not. These findings indicate that the different oral toxicity and host susceptibility observed among different BoNT serotypes could be partly determined by the serotype-specific interaction between HA33 and host carbohydrate receptors. Furthermore, we have identified a key structural water molecule that mediates the HA33/B–lactose interactions. It provides the structural basis for development of new receptor-mimicking compounds, which have enhanced binding affinity with HA33 through their water-displacing moiety. PMID:24631690

  8. Serum hyaluronan and laminin level in children with chronic hepatitis B during long-term lamivudine treatment.

    Science.gov (United States)

    Lebensztejn, Dariusz Marek; Skiba, Elzbieta; Sobaniec-Lotowska, Maria Elzbieta; Kaczmarski, Maciej

    2007-01-01

    The aim was to assess the effect of long-term lamivudine treatment on liver fibrosis by direct assessment of histological scores and by indirect assessment of serum biomarkers in children with chronic hepatitis B (chB). The observation was carried out on 31 children with biopsy proven chB who were nonresponders to previous IFNalpha therapy. The serum concentration of hyaluronan and laminin were measured before and up to 24 months of therapy. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis (score > 2 according to Batts & Ludwig). Serum hyaluronan and laminin level were significantly higher in children with chB compared to controls. There was a significant correlation between serum hyaluronan level and the stage of liver fibrosis. The ability of serum hyaluronan to differentiate children with advanced fibrosis from those with mild fibrosis was significant (AUC = 0.7767). Laminin did not allow a useful prediction. Two-year lamivudine treatment did not improve histological fibrosis but it caused significant decrease of serum hyaluronan level. Hyaluronan is a better fibrosis marker than laminin to diagnose children with advanced liver fibrosis. The significant decrease of hyaluronan level during therapy suggests antifibrotic effect of lamivudine in children with chB.

  9. Targeted Delivery of Hyaluronan-Immobilized Magnetic Ceramic Nanocrystals.

    Science.gov (United States)

    Wu, Hsi-Chin; Wang, Tzu-Wei; Hsieh, Shun-Yu; Sun, Jui-Sheng; Kang, Pei-Leun

    2016-01-01

    Effective cancer therapy relies on delivering the therapeutic agent precisely to the target site to improve the treatment outcome and to minimize side effects. Although surgery, chemotherapy, and radiotherapy are the standard methods commonly used in clinics, hyperthermia has been developed as a new and promising strategy for cancer therapy. In this study, magnetic bioceramic hydroxyapatite (mHAP) nanocrystals have been developed as heat mediator for intracellular hyperthermia. Hyaluronic acid (HA) modified mHAP nanocrystals are synthesized by a wet chemical precipitation process to achieve active targeting. The results demonstrate that the HA targeting moiety conjugated by a poly(ethylene glycol) (PEG) spacer arm is successfully immobilized on the surface of mHAP. The HA-modified mHAP possesses relatively good biocompatibility, an adequate biodegradation rate and superparamagnetic properties. The HA-modified mHAP could be localized and internalized into HA receptor-overexpressed malignant cells (e.g., MDA-MB-231 cell) and used as the heat generating agent for intracellular hyperthermia. The results from this study indicate that biocompatible HA-modified mHAP shows promise as a novel heat mediator and a specific targeting nanoagent for intracellular hyperthermia cancer therapy.

  10. Transforming growth factor-β1 induces EMT by the transactivation of epidermal growth factor signaling through HA/CD44 in lung and breast cancer cells.

    Science.gov (United States)

    Li, Lingmei; Qi, Lisha; Liang, Zhijie; Song, Wangzhao; Liu, Yanxue; Wang, Yalei; Sun, Baocun; Zhang, Bin; Cao, Wenfeng

    2015-07-01

    Epithelial-mesenchymal transition (EMT), a process closely related to tumor development, is regulated by a variety of signaling pathways and growth factors, such as transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF). Hyaluronan (HA) has been shown to induce EMT through either TGF-β1 or EGF signaling and to be a regulator of the crosstalk between these two pathways in fibroblasts. In this study, in order to clarify whether HA has the same effect in tumor cells, we utilized the lung cancer cell line, A549, and the breast cancer cell line, MCF-7, and found that the effects of stimulation with TGF-β1 were more potent than those of EGF in regulating the expression of EMT-associated proteins and in enhancing cell migration and invasion. In addition, we observed that TGF-β1 activated EGF receptor (EGFR) and its downstream AKT and extracellular signal-regulated kinase (ERK) pathways. Furthermore, we found that TGF-β1 upregulated the expression of hyaluronan synthases (HAS1, HAS2 and HAS3) and promoted the expression of CD44, a cell surface receptor for HA, which interacts with EGFR, resulting in the activation of the downstream AKT and ERK pathways. Conversely, treatment with 4-methylumbelliferone (4-MU; an inhibitor of HAS) prior to stimulation with TGF-β1, inhibited the expression of CD44 and EGFR, abolished the interaction between CD44 and EGFR. Furthermore, the use of shRNA targeting CD44 impaired the expression of EGFR, deactivated the AKT and ERK pathways, reversed EMT and decreased the migration and invasion ability of cells. In conclusion, our data demonstrate that TGF-β1 induces EMT by the transactivation of EGF signaling through HA/CD44 in lung and breast cancer cells.

  11. Morphological Effects of HA on the Cell Compatibility of Electrospun HA/PLGA Composite Nanofiber Scaffolds

    Directory of Open Access Journals (Sweden)

    Adnan Haider

    2014-01-01

    Full Text Available Tissue engineering is faced with an uphill challenge to design a platform with appropriate topography and suitable surface chemistry, which could encourage desired cellular activities and guide bone tissue regeneration. To develop such scaffolds, composite nanofiber scaffolds of nHA and sHA with PLGA were fabricated using electrospinning technique. nHA was synthesized using precipitation method, whereas sHA was purchased. The nHA and sHA were suspended in PLGA solution separately and electrospun at optimized electrospinning parameters. The composite nanofiber scaffolds were characterized by FE-SEM, EDX analysis, TEM, XRD analysis, FTIR, and X-ray photoelectron. The potential of the HA/PLGA composite nanofiber as bone scaffolds in terms of their bioactivity and biocompatibility was assessed by culturing the osteoblastic cells onto the composite nanofiber scaffolds. The results from in vitro studies revealed that the nHA/PLGA composite nanofiber scaffolds showed higher cellular adhesion, proliferation, and enhanced osteogenesis performance, along with increased Ca+2 ions release compared to the sHA/PLGA composite nanofiber scaffolds and pristine PLGA nanofiber scaffold. The results show that the structural dependent property of HA might affect its potential as bone scaffold and implantable materials in regenerative medicine and clinical tissue engineering.

  12. Rheology and Confocal Reflectance Microscopy as Probes of Mechanical Properties and Structure during Collagen and Collagen/Hyaluronan Self-Assembly

    Science.gov (United States)

    Yang, Ya-li; Kaufman, Laura J.

    2009-01-01

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37°C and 32°C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (tc), the slope of the growth phase (kg), and the arrest time (ta). The first two measures are determined by rheology, and the third by CRM. A frequency-independent rheological measure of gelation, tg, is also measured at 37°C. However, this quantity cannot be straightforwardly determined for gels formed at 32°C, indicating that percolation theory does not fully capture the dynamics of collagen network formation. The effects of collagen concentration and gelation temperature on kg, tc, and ta as well as on the mechanical properties and structure of these gels both during gelation and at equilibrium are elucidated. Composite collagen/HA gels are also prepared, and their properties are monitored at equilibrium and during gelation at 37°C and 32°C. We show that addition of HA subtly alters mechanical properties and structure of these systems both during the gelation process and at equilibrium. This occurs in a temperature-dependent manner, with the ratio of HA deposited on collagen fibers versus that distributed homogeneously between fibers increasing with decreasing gelation temperature. In addition to providing information on collagen and collagen/HA structure and mechanical properties during gelation, this work shows new ways in which rheology and microscopy can be used complementarily to reveal details of gelation processes. PMID:19217873

  13. Heavy Chain-Hyaluronan/Pentraxin 3 from Amniotic Membrane Suppresses Inflammation and Scarring in Murine Lacrimal Gland and Conjunctiva of Chronic Graft-versus-Host Disease

    Science.gov (United States)

    Ogawa, Yoko; He, Hua; Mukai, Shin; Imada, Toshihiro; Nakamura, Shigeru; Su, Chen-Wei; Mahabole, Megha; Tseng, Scheffer C. G.; Tsubota, Kazuo

    2017-01-01

    Chronic graft-versus-host disease (cGVHD) is a major complication of hematopoietic stem cell transplantation. Dry eye disease is the prominent ocular sequel of cGVHD and is caused by excessive inflammation and fibrosis in the lacrimal glands. Heavy chain-Hyaluronan/Pentraxin 3 (HC-HA/PTX3) is a complex purified from human amniotic membrane (AM) and known to exert anti-inflammatory and anti-scarring actions. In this study, we utilized a mouse model of cGVHD to examine whether HC-HA/PTX3 could attenuate dry eye disease elicited by cGVHD. Our results indicated that subconjunctival and subcutaneous injection of HC-HA/PTX3 preserved tear secretion and conjunctival goblet cell density and mitigated inflammation and scarring of the conjunctiva. Such therapeutic benefits were associated with suppression of scarring and infiltration of inflammatory/immune cells in the lacrimal glands. Furthermore, HC-HA/PTX3 significantly reduced the extent of infiltration of CD45+ CD4+ IL-17+ cells, CD45+ CD34+ collagen I+ CXCR4+ fibrocytes, and HSP47+ activated fibroblasts that were accompanied by upregulation of collagen type Iα1, collagen type IIIα1 and NF-kB in lacrimal glands. Collectively, these pre-clinical data help prove the concept that subcutaneous and subconjunctival injection of HC-HA/PTX3 is a novel approach to prevent dry eye disease caused by cGVHD and allow us to test its safety and efficacy in future human clinical trials. PMID:28165063

  14. Effects of leflunomide on hyaluronan synthases (HAS): NF-kappa B-independent suppression of IL-1-induced HAS1 transcription by leflunomide.

    Science.gov (United States)

    Stuhlmeier, Karl M

    2005-06-01

    Despite evidence that points to unfettered hyaluronic acid (HA) production as a culprit in the progression of rheumatic disorders, little is known about differences in regulation and biological functions of the three hyaluronan synthase (HAS) genes. Testing the effects of drugs with proven anti-inflammatory effects could help to clarify biological functions of these genes. In this study, we demonstrate that leflunomide suppresses HA release in fibroblast-like synoviocytes (FLS) in a dose-dependent manner. We further demonstrate that leflunomide suppresses HA synthase activity, as determined by (14)C-glucuronic acid incorporation assays. Additional experiments revealed that in FLS, leflunomide specifically blocked the induction of HAS1. HAS2 and HAS3, genes that are, in contrast to HAS1, constitutively expressed in FLS, are not significantly affected. Leflunomide can function as a NF-kappaB inhibitor. However, EMSA experiments demonstrate that at the concentrations used, leflunomide neither interferes with IL-1beta- nor with PMA-induced NF-kappaB translocation. Furthermore, reconstituting the pyrimidine synthase pathway did not lead to the restoration of IL-1beta-induced HAS1 activation. More importantly, two tyrosine kinase inhibitors mimicked the effect of leflunomide in that both blocked IL-1beta-induced HAS1 activation without affecting HAS2 or HAS3. These data point at HAS1 activation as the possible cause for unfettered HA production in rheumatoid arthritis and might explain, at least in part, the beneficial effects of leflunomide treatment. These findings also support the concept that IL-1beta-induced HAS1 activation depends on the activation of tyrosine kinases, and indicate that leflunomide blocks HA release by suppressing tyrosine kinases rather than through inhibition of NF-kappaB translocation.

  15. Rheology and confocal reflectance microscopy as probes of mechanical properties and structure during collagen and collagen/hyaluronan self-assembly.

    Science.gov (United States)

    Yang, Ya-li; Kaufman, Laura J

    2009-02-18

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37 degrees C and 32 degrees C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (t(c)), the slope of the growth phase (k(g)), and the arrest time (t(a)). The first two measures are determined by rheology, and the third by CRM. A frequency-independent rheological measure of gelation, t(g), is also measured at 37 degrees C. However, this quantity cannot be straightforwardly determined for gels formed at 32 degrees C, indicating that percolation theory does not fully capture the dynamics of collagen network formation. The effects of collagen concentration and gelation temperature on k(g), t(c), and t(a) as well as on the mechanical properties and structure of these gels both during gelation and at equilibrium are elucidated. Composite collagen/HA gels are also prepared, and their properties are monitored at equilibrium and during gelation at 37 degrees C and 32 degrees C. We show that addition of HA subtly alters mechanical properties and structure of these systems both during the gelation process and at equilibrium. This occurs in a temperature-dependent manner, with the ratio of HA deposited on collagen fibers versus that distributed homogeneously between fibers increasing with decreasing gelation temperature. In addition to providing information on collagen and collagen/HA structure and mechanical properties during gelation, this work shows new ways in which rheology and microscopy can be used complementarily to reveal details of gelation processes.

  16. Stimulation of porcine bone marrow stromal cells by hyaluronan, dexamethasone and rhBMP-2

    DEFF Research Database (Denmark)

    Zou, Xuenong; Li, Haisheng; Chen, Li

    2004-01-01

    In the interest of optimizing osteogenesis in in vitro, the present study sought to determine how porcine bone marrow stromal cell (BMSc) would respond to different concentrations of hyaluronan (HY) and its different combinations with dexamethasone (Dex) and recombinant human bone morphogenic pro...

  17. Splanchnic and renal extraction of circulating hyaluronan in patients with alcoholic liver disease

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Bentsen, K D; Laurent, T C

    1988-01-01

    hyaluronan was inversely correlated to indocyanine green clearance (r = -0.85, P less than 0.001) and to galactose elimination capacity (r = -0.62, P less than 0.02), but positively correlated to portal pressure (determined as wedged-to-free hepatic vein pressure) (r = 0.92, P less than 0.001). Splanchnic...

  18. Synthesis of a hexasaccharide partial sequence of hyaluronan for click chemistry and more

    Directory of Open Access Journals (Sweden)

    Marina Bantzi

    2015-04-01

    Full Text Available In the present work, the synthesis of a hexasaccharide partial sequence of hyaluronan equipped with a terminal azido moiety is reported. This hexasaccharide can be used for the attachment on surfaces by means of click chemistry and after suitable deprotection for biophysical studies.

  19. Can hyaluronan injections augment deficient papillae at implant-supported crowns in the anterior maxilla?

    DEFF Research Database (Denmark)

    Bertl, Kristina; Gotfredsen, Klaus; Jensen, Simon S;

    2017-01-01

    OBJECTIVES: The present randomized controlled trial aimed to assess the effect of hyaluronan (HY) injections to augment deficient interproximal papillae at implant-supported crowns in the anterior maxilla. METHODS: Twenty-two patients with a deficient papilla in the anterior maxilla next to an im...

  20. Heparin prevents intracellular hyaluronan synthesis and autophagy responses in hyperglycemic dividing mesangial cells and activates synthesis of an extensive extracellular monocyte-adhesive hyaluronan matrix after completing cell division.

    Science.gov (United States)

    Wang, Aimin; Ren, Juan; Wang, Christina P; Hascall, Vincent C

    2014-03-28

    Growth-arrested rat mesangial cells (RMCs) at a G0/G1 interphase stimulated to divide in hyperglycemic medium initiate intracellular hyaluronan synthesis that induces autophagy/cyclin D3-induced formation of a monocyte-adhesive extracellular hyaluronan matrix after completing cell division. This study shows that heparin inhibits the intracellular hyaluronan synthesis and autophagy responses, but at the end of cell division it induces synthesis of a much larger extracellular monocyte-adhesive hyaluronan matrix. Heparin bound to RMC surfaces by 1 h, internalizes into the Golgi/endoplasmic reticulum region by 2 h, and was nearly gone by 4 h. Treatment by heparin for only the first 4 h was sufficient for its function. Streptozotocin diabetic rats treated daily with heparin showed similar results. Glomeruli in sections of diabetic kidneys showed extensive accumulation of autophagic RMCs, increased hyaluronan matrix, and influx of macrophages over 6 weeks. Hyaluronan staining in the glomeruli of heparin-treated diabetic rats was very high at week 1 and decreased to near control level by 6 weeks without any RMC autophagy. However, the influx of macrophages by 6 weeks was as pronounced as in diabetic glomeruli. The results are as follows: 1) heparin blocks synthesis of hyaluronan in intracellular compartments, which prevents the autophagy and cyclin D3 responses thereby allowing RMCs to complete cell division and sustain function; 2) interaction of heparin with RMCs in early G1 phase is sufficient to induce signaling pathway(s) for its functions; and 3) influxed macrophages effectively remove the hyaluronan matrix without inducing pro-fibrotic responses that lead to nephropathy and proteinurea in diabetic kidneys.

  1. Mutual Exclusivity of Hyaluronan and Hyaluronidase in Invasive Group A Streptococcus*

    Science.gov (United States)

    Henningham, Anna; Yamaguchi, Masaya; Aziz, Ramy K.; Kuipers, Kirsten; Buffalo, Cosmo Z.; Dahesh, Samira; Choudhury, Biswa; Van Vleet, Jeremy; Yamaguchi, Yuka; Seymour, Lisa M.; Ben Zakour, Nouri L.; He, Lingjun; Smith, Helen V.; Grimwood, Keith; Beatson, Scott A.; Ghosh, Partho; Walker, Mark J.; Nizet, Victor; Cole, Jason N.

    2014-01-01

    A recent analysis of group A Streptococcus (GAS) invasive infections in Australia has shown a predominance of M4 GAS, a serotype recently reported to lack the antiphagocytic hyaluronic acid (HA) capsule. Here, we use molecular genetics and bioinformatics techniques to characterize 17 clinical M4 isolates associated with invasive disease in children during this recent epidemiology. All M4 isolates lacked HA capsule, and whole genome sequence analysis of two isolates revealed the complete absence of the hasABC capsule biosynthesis operon. Conversely, M4 isolates possess a functional HA-degrading hyaluronate lyase (HylA) enzyme that is rendered nonfunctional in other GAS through a point mutation. Transformation with a plasmid expressing hasABC restored partial encapsulation in wild-type (WT) M4 GAS, and full encapsulation in an isogenic M4 mutant lacking HylA. However, partial encapsulation reduced binding to human complement regulatory protein C4BP, did not enhance survival in whole human blood, and did not increase virulence of WT M4 GAS in a mouse model of systemic infection. Bioinformatics analysis found no hasABC homologs in closely related species, suggesting that this operon was a recent acquisition. These data showcase a mutually exclusive interaction of HA capsule and active HylA among strains of this leading human pathogen. PMID:25266727

  2. Hydrocellular foam dressing promotes wound healing along with increases in hyaluronan synthase 3 and PPARα gene expression in epidermis.

    Directory of Open Access Journals (Sweden)

    Takumi Yamane

    Full Text Available BACKGROUND: Hydrocellular foam dressing, modern wound dressing, induces moist wound environment and promotes wound healing: however, the regulatory mechanisms responsible for these effects are poorly understood. This study was aimed to reveal the effect of hydrocellular foam dressing on hyaluronan, which has been shown to have positive effects on wound healing, and examined its regulatory mechanisms in rat skin. METHODOLOGY/PRINCIPAL FINDINGS: We created two full-thickness wounds on the dorsolateral skin of rats. Each wound was covered with either a hydrocellular foam dressing or a film dressing and hyaluronan levels in the periwound skin was measured. We also investigated the mechanism by which the hydrocellular foam dressing regulates hyaluronan production by measuring the gene expression of hyaluronan synthase 3 (Has3, peroxisome proliferator-activated receptor α (PPARα, and CD44. Hydrocellular foam dressing promoted wound healing and upregulated hyaluronan synthesis, along with an increase in the mRNA levels of Has3, which plays a primary role in hyaluronan synthesis in epidermis. In addition, hydrocellular foam dressing enhanced the mRNA levels of PPARα, which upregulates Has3 gene expression, and the major hyaluronan receptor CD44. CONCLUSIONS/SIGNIFICANCE: These findings suggests that hydrocellular foam dressing may be beneficial for wound healing along with increases in hyaluronan synthase 3 and PPARα gene expression in epidermis. We believe that the present study would contribute to the elucidation of the mechanisms underlying the effects of hydrocellular foam dressing-induced moist environment on wound healing and practice evidence-based wound care.

  3. Hyaluronan-Based Therapy for Metastatic Prostate Cancer

    Science.gov (United States)

    2016-09-01

    labeled HA-NPs (50 µg/mL) at various incubation times. Fluorescence mean ± S.D., 500 cells. D) Cell viability of PC3 (top, blue ) and HEK293T cells... biotechnology professionals, manufacturing experts, clinicians and entrepreneurs to discuss clinical translation of a lead biologic drug and the development...clinical research.  Furthermore, I attended biotechnology career development programs through Johns Hopkins’ Biomedical Careers Initiative that

  4. Adiponectin promotes hyaluronan synthesis along with increases in hyaluronan synthase 2 transcripts through an AMP-activated protein kinase/peroxisome proliferator-activated receptor-{alpha}-dependent pathway in human dermal fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Yamane, Takumi; Kobayashi-Hattori, Kazuo [Department of Nutritional Sciences, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502 (Japan); Oishi, Yuichi, E-mail: y3oishi@nodai.ac.jp [Department of Nutritional Sciences, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502 (Japan)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Adiponectin promotes hyaluronan synthesis along with an increase in HAS2 transcripts. Black-Right-Pointing-Pointer Adiponectin also increases the phosphorylation of AMPK. Black-Right-Pointing-Pointer A pharmacological activator of AMPK increases mRNA levels of PPAR{alpha} and HAS2. Black-Right-Pointing-Pointer Adiponectin-induced HAS2 mRNA expression is blocked by a PPAR{alpha} antagonist. Black-Right-Pointing-Pointer Adiponectin promotes hyaluronan synthesis via an AMPK/PPAR{alpha}-dependent pathway. -- Abstract: Although adipocytokines affect the functions of skin, little information is available on the effect of adiponectin on the skin. In this study, we investigated the effect of adiponectin on hyaluronan synthesis and its regulatory mechanisms in human dermal fibroblasts. Adiponectin promoted hyaluronan synthesis along with an increase in the mRNA levels of hyaluronan synthase 2 (HAS2), which plays a primary role in hyaluronan synthesis. Adiponectin also increased the phosphorylation of AMP-activated protein kinase (AMPK). A pharmacological activator of AMPK, 5-aminoimidazole-4-carboxamide-1{beta}-ribofuranoside (AICAR), increased mRNA levels of peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}), which enhances the expression of HAS2 mRNA. In addition, AICAR increased the mRNA levels of HAS2. Adiponectin-induced HAS2 mRNA expression was blocked by GW6471, a PPAR{alpha} antagonist, in a concentration-dependent manner. These results show that adiponectin promotes hyaluronan synthesis along with increases in HAS2 transcripts through an AMPK/PPAR{alpha}-dependent pathway in human dermal fibroblasts. Thus, our study suggests that adiponectin may be beneficial for retaining moisture in the skin, anti-inflammatory activity, and the treatment of a variety of cutaneous diseases.

  5. Characterization of polyelectrolyte behavior of the polysaccharides chitosan, heparin, and hyaluronan, by light scattering and viscometry.

    Science.gov (United States)

    Boddohi, Soheil; Yonemura, Susan; Kipper, Matt

    2008-03-01

    This study on the polyelectrolyte behavior of polysaccharides in solution is motivated by our recent work in development of nanostructured polysaccharide-based surface coatings. Chitosan behaves as a weak polycation, and hyaluronan behaves as a weak polyanion, while heparin behaves as a strong polyanion. The ability to control the conformation of these polysaccharides in solution, by changing the solution ionic strength and pH may offer the opportunity to further tune the nanoscale features of polysaccharide-based surface coatings assembled from solution. In the work reported here, the solution conformation of these polymers is determined from gel permeation chromatography coupled to differential refractive index, light scattering, and viscometry detection. These results are related to the nanostructure of chitosan-heparin and chitosan-hyaluronan surface coatings based on polyelectrolyte multilayers.

  6. High molecular weight hyaluronan for treatment of chronic shoulder pain associated with glenohumeral arthritis

    OpenAIRE

    Weil AJ

    2011-01-01

    Arnold J WeilNon-Surgical Orthopedics PC, Marietta, GA, USABackground: There is insufficient evidence to determine whether intra-articular injections may be effective for treatment of glenohumeral osteoarthritis. Euflexxa® (high molecular weight hyaluronate), a bioengineered high molecular weight hyaluronan, has been shown to be a safe and effective treatment for patients with knee osteoarthritis. There is also support for the use of hyaluronate injection for the treatment of chronic ...

  7. Charged Triazole Cross-Linkers for Hyaluronan-Based Hybrid Hydrogels

    Directory of Open Access Journals (Sweden)

    Maike Martini

    2016-09-01

    Full Text Available Polyelectrolyte hydrogels play an important role in tissue engineering and can be produced from natural polymers, such as the glycosaminoglycan hyaluronan. In order to control charge density and mechanical properties of hyaluronan-based hydrogels, we developed cross-linkers with a neutral or positively charged triazole core with different lengths of spacer arms and two terminal maleimide groups. These cross-linkers react with thiolated hyaluronan in a fast, stoichiometric thio-Michael addition. Introducing a positive charge on the core of the cross-linker enabled us to compare hydrogels with the same interconnectivity, but a different charge density. Positively charged cross-linkers form stiffer hydrogels relatively independent of the size of the cross-linker, whereas neutral cross-linkers only form stable hydrogels at small spacer lengths. These novel cross-linkers provide a platform to tune the hydrogel network charge and thus the mechanical properties of the network. In addition, they might offer a wide range of applications especially in bioprinting for precise design of hydrogels.

  8. TRPM3 channel stimulated by pregnenolone sulphate in synovial fibroblasts and negatively coupled to hyaluronan

    Directory of Open Access Journals (Sweden)

    English Anne A

    2010-06-01

    Full Text Available Abstract Background Calcium-permeable channels are known to have roles in many mammalian cell types but the expression and contribution of such ion channels in synovial cells is mostly unknown. The objective of this study was to investigate the potential relevance of Transient Receptor Potential Melastatin 3 (TRPM3 channel to fibroblast-like synoviocytes (FLSs of patients with rheumatoid arthritis. Methods The study used RT-PCR and immunofluorescence to detect mRNA and protein. Intracellular calcium measurement detected channel activity in a FLS cell-line and primary cultures of FLSs from patients with rheumatoid arthritis. Enzyme-linked immunosorbent assays measured hyaluronan. Results Endogenous expression of TRPM3 was detected. Previously reported stimulators of TRPM3 sphingosine and pregnenolone sulphate evoked sustained elevation of intracellular calcium in FLSs. The FLS cell-line showed an initial transient response to sphingosine which may be explained by TRPV4 channels but was not observed in FLSs from patients. Blocking antibody targeted to TRPM3 inhibited sustained sphingosine and pregnenolone sulphate responses. Secretion of hyaluronan, which contributes adversely in rheumatoid arthritis, was suppressed by pregnenolone sulphate in FLSs from patients and the effect was blocked by anti-TRPM3 antibody. Conclusions The data suggest that FLSs of patients with rheumatoid arthritis express TRPM3-containing ion channels that couple negatively to hyaluronan secretion and can be stimulated by pharmacological concentrations of pregnenolone sulphate.

  9. Effect of hyaluronan on periodontitis: A clinical and histological study

    Directory of Open Access Journals (Sweden)

    Gauri Gontiya

    2012-01-01

    Full Text Available Background: Conventional, non-surgical periodontal therapy consists of supra- and subgingival tooth debridement. However, it is a technically demanding procedure and is not always efficient at eradicating all periodontal pathogens and in reducing inflammation. Therefore, local subgingival application of other chemotherapeutic agents may be used as an adjunct to non-surgical therapy. The aim of this study was to investigate the clinical and histological outcomes of local subgingival application of 0.2% hyaluronic acid gel (GENGIGEL® as an adjunct to scaling and root planing (SRP in chronic periodontitis patients. Materials and Methods: One hundred and twenty sites were chosen from 26 patients with chronic periodontitis (criteria being periodontal pockets ≥5mm. Experimental sites additionally received HA gel subgingivally at baseline, 1 st , 2 nd , and 3 rd week. Clinical parameters were re-assessed at 4 th , 6 th , and 12 th week. At 4 th week recall, a gingival biopsy was obtained from test and control site for histologic examination. Results: Intra-group analysis of all the clinical parameters at all sites from baseline to 4 th , 6 th , and 12 th week showed statistically significant changes. Experimental sites showed statistically significant improvement in Gingival index and Bleeding index at 6 th and 12 th week when compared with control sites. However, no statistically significant differences were observed in the PPD and RAL between control and experimental sites at 4 th , 6 th , and 12 th week time interval. No statistically significant association was found between the histological grading of the sites that received HA treatment. Conclusion: Subgingival placement of 0.2% HA gel along with SRP provided a significant improvement in gingival parameters. However, no additional benefit was found in periodontal parameters. Histologically, experimental sites showed reduced inflammatory infiltrate, but it was not statistically significant.

  10. [Hypoallergenic milks (HA formulas) in infant nutrition].

    Science.gov (United States)

    Zoppi, G

    1993-01-01

    According to the definition of the European Scientific Committee for Food, hypoallergenic or hypoantigenic formulas (HA-formulas) are those which contain hydrolysed protein derived both from casein or whey. Soy-based formulas are not comprised in this definition since it has been demonstrated from several years that soy-protein, in several circumstances, may be highly allergenic. Hypoallergenic formulas contain besides hydrolysed protein, carbohydrate and lipid in amount and proportion similar to those indicated by ESPGAN recommendations on adapted formulas. As far as it concerns composition in lipid, recently great attention has been given to optimal supply and ratio of omega 3 and omega 6 fatty acids. Hypoallergenic formulas are therefore suitable for balanced nutrition of suckling infants. Specific indications on prevention of atopic diseases are not treated.

  11. HA/Ti composite for biomedical application by mechanical milling

    Institute of Scientific and Technical Information of China (English)

    刘咏; 刘芳; 周科朝; 黄伯云

    2003-01-01

    In order to overcome the poor mechanical properties of HA and the low bioactivity of Ti, HA/Ti com-posites with various compositions were prepared by mechanical milling. The effects of milling condition and the com-position on the microstructure, the density and the hardness of the composites were studied. The results show thatduring the ball milling process, Ti particles are refined and the homogeneity of the HA/Ti mixtures is improved;HA will partially decompose due to the existence of Ti and high sintering temperature. The microstructure of HA/Ti composites is highly dependent on the milling condition and the composition. In the microstructure, Ti phase con-nects to be a continuous network, and HA/Ti mixtures disperse in the network. The longer the milling time, the fi-ner the network will be. The density of HA/Ti composites decreases with the content of HA increasing and themilling time prolonging, because HA deteriorates the sinterability of Ti. The hardness of HA/Ti composites increa-ses firstly with the content of HA increasing, and then drops when the content of HA exceeds 30%. Addition ofHA will strengthen the HA/Ti composite but will decrease the density of the composite, which accounts for theeffect of HA on the hardness of the composites.

  12. Enhanced Interfacial Adhesion in HDPE/HA Composites by Surface Modification of HA Particles via in situ Polymerization and Copolymerization

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Hydroxyapatite ( HA )-reinforced high density polyethylene (HDPE) was developed as a bone replacement material. In order to enhance the interfacial bondiag between HA and polyethylene and improve the mechanical properties of HDPE/ HA composites, the surface of the micron-sized HA particles was modified by in situ polymerization of butyl acrylate ( BA ) and in situ copolynerization of vinyl triethoxyl silane (VTES) and BA ,then the modified HA particles were compounded with HDPE. The effects of the surface modification of HA on morphology and mechanical properties of HDPE/ HA composites were investigated. The experimental results show that the presence of HA particles does not inhibit the polymerization of BA . The poly( butyl acrylate) ( PBA ) segments on the HA surface enhance the compatibility between HA and HDPE, improve the dispersion of HA particles in HDPE matrix, and enhance the interfacial ndhesion between HA and matrix. Surface modifications, especially by in situ copolymerization of VTES and BA , significantly increase notch impact strengths and marginal stiffness and tensile strengths of HDPE/ HA composites. And it is found that there is a critical thickness of PBA coating on HA particles for optimum mechanical properties of HDPE / HA composites.

  13. Superovulation of beef cattle with a split-single intramuscular administration of Folltropin-V in two concentrations of hyaluronan.

    Science.gov (United States)

    Tríbulo, Andrés; Rogan, Dragan; Tríbulo, Humberto; Tríbulo, Ricardo; Mapletoft, Reuben J; Bó, Gabriel A

    2012-05-01

    Three experiments were designed to evaluate the superovulatory response of beef cows following two intramuscular (IM) administrations 48 h apart of Folltropin-V diluted in reduced concentrations of hyaluronan (Split-single IM administrations; Experiment 1-300 mg Folltropin-V on the first day and 100 mg 48 h later; Experiment 2-200 mg Folltropin-V on the first day and 100 mg 48 h later). In Experiments 1 and 2, superovulatory response and ova embryo/embryo production did not differ between donors receiving twice daily IM of Folltropin-V over 4 days and those given a Split-single IM administration of Folltropin-V diluted in 10 mg/mL hyaluronan solution. Experiment 3 compared Split-single IM administration of Folltropin-V diluted in two hyaluronan concentrations (5 or 10 mg/mL) with Folltropin-V diluted in saline and administered twice-daily over 4 days. Beef cows (17 Angus and 12 Simmental) were randomly assigned to one of three treatment groups to be superstimulated three times in a cross-over design, so that all cows received all treatments. A total dose of 300 mg Folltropin-V was divided into twice-daily IM over 4 days, or in two IM treatment 48 h apart (200 mg on first day and 100 mg 48 h later) in the hyaluronan groups. Mean (± SEM) numbers of transferable embryos did not differ among treatment groups (Control: 4.0 ± 0.8; 10 mg/mL hylauronan: 5.0 ± 0.9; 5 mg/mL hyaluronan: 6.1 ± 1.3). We concluded that the Split-single IM administration of Folltropin-V diluted in either concentration of hyaluronan resulted in a comparable superovulatory response to the traditional twice-daily protocol.

  14. Heparan sulfate proteoglycan isoforms of the CD44 hyaluronan receptor induced in human inflammatory macrophages can function as paracrine regulators of fibroblast growth factor action.

    Science.gov (United States)

    Jones, M; Tussey, L; Athanasou, N; Jackson, D G

    2000-03-17

    The CD44 glycoprotein is expressed in multiple isoforms on a variety of cell types where it functions as a receptor for hyaluronan-mediated motility. Recently, interest has centered on CD44 heparan sulfate proteoglycan (HSPG) isoforms because of their potential to sequester heparin-binding growth factors and chemokines. Expression of these isoforms on ectodermal cells has recently been shown to regulate limb morphogenesis via presentation of fibroblast growth factor (FGF) 4/FGF 8 while expression on tumor cells was shown to sequester hepatocyte growth factor and promote tumor dissemination. To date, however, CD44 HSPG expression in tissue macrophages and lymphocytes has not been adequately investigated, despite the fact these cells actively synthesize growth factors and chemokines and indirect evidence that monocyte CD44 sequesters macrophage inflammatory protein-1beta. Here we show primary human monocytes rather than lymphocytes express CD44 HSPGs, but only following in vitro differentiation to macrophages or activation with the proinflammatory cytokine interleukin-1alpha or bacterial lipopolysaccharide. Furthermore, we show these isoforms are preferentially modified with heparan rather than chondroitin sulfate, bind the macrophage-derived growth factors FGF-2, vascular endothelial growth factor, and heparin-binding epidermal growth factor with varying affinities (K(d) 25-330 nM) and in the case of FGF-2, can stimulate productive binding to the high affinity tyrosine kinase FGF receptor 1 (FGFR1). In contrast, we find no evidence for significant binding to C-C chemokines. Last, we confirm by immunofluorescent antibody staining that inflamed synovial membrane macrophages express CD44 HSPGs and that expression is greatest in cells containing high FGF-2 levels. These results suggest a paracrine role for macrophage CD44 HSPG isoforms in the regulation of growth factor action during inflammation.

  15. Reconstruction of HaSNPV with helicoverpa hormone receptor 3

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to develop a more efficient virus for controlling the cotton bollworm Helicoverpa armigera,Helicoverpa hormone receptor 3 (HHR3), which is involved in the ecdysteroid regulatory pathway, was used to genetically modify wild HaSNPV. HaSNPV-HHR3 budded virus and occlusion body virus were constructed in three steps: preparation of pFastBacHaPhpP10-HHR3 donor plasmid, transposition of HHR3 into the HaBacHZ8 bacmid, and transfection of HzAM1 cells to get HaSNPV-HHR3 virus. HHR3was proved to be expressed in the HaSNPV-HHR3 virus infected HzAM1 cells by immunoblotting. Results of bioassay indicated that the body weight of the HaSNPV-HHR3 infected larvae was lower than the larvae infected with wild virus and uninfected normal larvae, which suggests that HaSNPV-HHR3 delayed larval growth.

  16. Receptor for hyaluronan mediated motility (RHAMM/HMMR) is a novel target for promoting subcutaneous adipogenesis.

    Science.gov (United States)

    Bahrami, S B; Tolg, C; Peart, T; Symonette, C; Veiseh, M; Umoh, J U; Holdsworth, D W; McCarthy, J B; Luyt, L G; Bissell, M J; Yazdani, A; Turley, E A

    2017-03-01

    Hyaluronan, CD44 and the Receptor for Hyaluronan-Mediated Motility (RHAMM, gene name HMMR) regulate stem cell differentiation including mesenchymal progenitor differentiation. Here, we show that CD44 expression is required for subcutaneous adipogenesis, whereas RHAMM expression suppresses this process. We designed RHAMM function blocking peptides to promote subcutaneous adipogenesis as a clinical and tissue engineering tool. Adipogenic RHAMM peptides were identified by screening for their ability to promote adipogenesis in culture assays using rat bone marrow mesenchymal stem cells, mouse pre-adipocyte cell lines and primary human subcutaneous pre-adipocytes. Oil red O uptake into fat droplets and adiponectin production were used as biomarkers of adipogenesis. Positive peptides were formulated in either collagen I or hyaluronan (Orthovisc) gels then assessed for their adipogenic potential in vivo following injection into dorsal rat skin and mammary fat pads. Fat content was quantified and characterized using micro CT imaging, morphometry, histology, RT-PCR and ELISA analyses of adipogenic gene expression. Injection of screened peptides increased dorsal back subcutaneous fat pad area (208.3 ± 10.4 mm(2)versus control 84.11 ± 4.2 mm(2); p 5 weeks as detected by micro CT imaging and perilipin 1 mRNA expression. RHAMM expression suppresses while blocking peptides promote expression of PPARγ, C/EBP and their target genes. Blocking RHAMM function by peptide injection or topical application is a novel and minimally invasive method for potentially promoting subcutaneous adipogenesis in lipodystrophic diseases and a complementary tool to subcutaneous fat augmentation techniques.

  17. Activation of the FGFR-STAT3 pathway in breast cancer cells induces a hyaluronan-rich microenvironment that licenses tumor formation.

    Science.gov (United States)

    Bohrer, Laura R; Chuntova, Pavlina; Bade, Lindsey K; Beadnell, Thomas C; Leon, Ronald P; Brady, Nicholas J; Ryu, Yungil; Goldberg, Jodi E; Schmechel, Stephen C; Koopmeiners, Joseph S; McCarthy, James B; Schwertfeger, Kathryn L

    2014-01-01

    Aberrant activation of fibroblast growth factor receptors (FGFR) contributes to breast cancer growth, progression, and therapeutic resistance. Because of the complex nature of the FGF/FGFR axis, and the numerous effects of FGFR activation on tumor cells and the surrounding microenvironment, the specific mechanisms through which aberrant FGFR activity contributes to breast cancer are not completely understood. We show here that FGFR activation induces accumulation of hyaluronan within the extracellular matrix and that blocking hyaluronan synthesis decreases proliferation, migration, and therapeutic resistance. Furthermore, FGFR-mediated hyaluronan accumulation requires activation of the STAT3 pathway, which regulates expression of hyaluronan synthase 2 (HAS2) and subsequent hyaluronan synthesis. Using a novel in vivo model of FGFR-dependent tumor growth, we demonstrate that STAT3 inhibition decreases both FGFR-driven tumor growth and hyaluronan levels within the tumor. Finally, our results suggest that combinatorial therapies inhibiting both FGFR activity and hyaluronan synthesis is more effective than targeting either pathway alone and may be a relevant therapeutic approach for breast cancers associated with high levels of FGFR activity. In conclusion, these studies indicate a novel targetable mechanism through which FGFR activation in breast cancer cells induces a protumorigenic microenvironment.

  18. A hyaluronan-based nerve guide : in vitro cytotoxicity, subcutaneous tissue reactions, and degradation in the rat

    NARCIS (Netherlands)

    Jansen, K; van Wachem, PB; Nicolai, JPA; de Leij, LFMH; van Luyn, MJA; van der Werf, J.F.A.

    2004-01-01

    We investigated possible cytotoxic effects, biocompatibility, and degradation of a hyaluronan-based conduit for peripheral nerve repair. We subjected the conduits to an in vitro fibroblast cytotoxicity test and concluded that the conduits were not cytotoxic. Subsequently, we implanted the conduits s

  19. Hyaluronan, neural stem cells and tissue reconstruction after acute ischemic stroke.

    Science.gov (United States)

    Moshayedi, Pouria; Carmichael, S Thomas

    2013-01-01

    Focal stroke is a disabling disease with lifelong sensory, motor and cognitive impairments. Given the paucity of effective clinical treatments, basic scientists are developing novel options for protection of the affected brain and regeneration of lost tissue. Tissue bioengineering and stem/progenitor cell treatments have both been individually pursued for stroke neural repair therapies, with some benefit in tissue recovery. Emerging directions in stroke neural repair approaches combine these two therapies to use biopolymers with stem/progenitor transplants to promote greater cell survival in the transplant and directed delivery of bioactive molecules to the transplanted cells and the adjacent injured tissue. In this review the background literature on a combined use of neural stem/progenitor cells encapsulated in hyaluronan gels is discussed and the way this therapeutic approach can affect the important processes involved in brain tissue reconstruction, such as angiogenesis, axon regeneration, neural differentiation and inflammation is clarified. The glycosaminoglycan hyaluronan can optimize those processes and be employed in a successful neural tissue engineering approach.

  20. Survival of cord blood haematopoietic stem cells in a hyaluronan hydrogel for ex vivo biomimicry.

    Science.gov (United States)

    Demange, Elise; Kassim, Yusra; Petit, Cyrille; Buquet, Catherine; Dulong, Virginie; Cerf, Didier Le; Buchonnet, Gérard; Vannier, Jean-Pierre

    2013-11-01

    Haematopoietic stem cells (HSCs) and haematopoietic progenitor cells (HPCs) grow in a specified niche in close association with the microenvironment, the so-called 'haematopoietic niche'. Scaffolds have been introduced to overcome the liquid culture limitations, mimicking the presence of the extracellular matrix (ECM). In the present study the hyaluronic acid scaffold, already developed in the laboratory, has been used for the first time to maintain long-term cultures of CD34⁺ haematopoietic cells obtained from human cord blood. One parameter investigated was the impact on ex vivo survival of CD34⁺ cord blood cells (CBCs) on the hyaluronic acid surface, immobilized with peptides containing the RGD motif. This peptide was conjugated by coating the hyaluronan hydrogel and cultured in serum-free liquid phase complemented with stem cell factor (SCF), a commonly indispensable cytokine for haematopoiesis. Our work demonstrated that these hyaluronan hydrogels were superior to traditional liquid cultures by maintaining and expanding the HPCs without the need for additional cytokines, and a colonization of 280-fold increment in the hydrogel compared with liquid culture after 28 days of ex vivo expansion. Copyright © 2012 John Wiley & Sons, Ltd.

  1. New E-beam-initiated hyaluronan acrylate cryogels support growth and matrix deposition by dermal fibroblasts.

    Science.gov (United States)

    Thönes, S; Kutz, L M; Oehmichen, S; Becher, J; Heymann, K; Saalbach, A; Knolle, W; Schnabelrauch, M; Reichelt, S; Anderegg, U

    2017-01-01

    Cryogels made of components of natural extracellular matrix components are potent biomaterials for bioengineering and regenerative medicine. Human dermal fibroblasts are key cells for tissue replacement during wound healing. Thus, any biomaterial for wound healing applications should enable growth, differentiation and matrix synthesis by these cells. Cryogels are highly porous scaffolds consisting of a network of interconnected pores. Here, we used a novel group of cryogels generated from acrylated hyaluronan where the polymerization was initiated by accelerated electrons (E-beam). This novel procedure omits any toxic polymerization initiators and results in sterile, highly elastic scaffolds with adjustable pore size, excellent swelling and low flow resistance properties. We show that these cryogels are effective 3D-substrates for long-term cultures of human dermal fibroblasts in vitro. The cells proliferate for at least 28days throughout the cryogels and deposit their own matrix in the pores. Moreover, key modulators of dermal fibroblasts during wound healing like TGFβ and PDGF efficiently stimulated the expression of wound healing-relevant genes. In conclusion, electron beam initiated cryogels of acrylated hyaluronan represent a functional and cell compatible biomaterial that could be adapted for special wound healing applications by further functionalization. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. The effect of different doses of hyaluronan on sperm morphology, motility, vitality and fertilization capability in mouse

    Directory of Open Access Journals (Sweden)

    S. Sayadi

    2006-07-01

    Full Text Available Background: Hyaluronan has an important role on the permeability and motility of sperm and the interaction of gametes and these can play a considerable role on the fertility rate. Therefore, in this study, we assessed the effect of different doses of hyaluronan on the morphology, motility, vitality and fertility rate of mice. Methods: We used 40 mice (6-8 week in this study which twenty of them were male and the rest were female. The sperm of each male mouse were divided into four groups. The group 1 (control: They were maintained in RPMI media without any hyaluronan supplementation for 2 hour. Hyaluronan with the doses of 750, 1000 and 1250 µg/ml were added into RPMI media in groups 2, 3 and 4, respectively. After 2 hour. incubation, the numbers of sperms were assessed, using haemocytometer. Also, their morphology with papanicolaeu staining and their vitality with Eosin B dye were assessed. As well as sperms motility measured under inverted microscope by observation and fertility rate evaluated after routine IVF by counting two-cell stage embryos. Results: Our results demonstrated that, the dose of 750 µ g/ml has the greatest effect on the motility, vitality and fertility rate of sperms. The effect of dose of 1000 µ g/ml also was positive on them. On the other hand, none of these doses had any effect on sperm morphology. Conclusion: Hyaluronan may have an influence on motility, vitality and fertility rate of sperms and the dose of 750µ g/ml had a significant effect on these factors.

  3. HA/UHMWPE Nanocomposite Produced by Twin-screw Extrusion

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The HA/UHMWPE nanocomposite is compounded by twin-screw extrusion of the HA and UHMWPE powder mixture in paraffin oil and then compression molded to a sheet form. TGA measurement shows the HA weight loss after processing is about 1%-2% . FTIR spectra indicate the paraffin oil residue is trivial and UHMWPE is not oxidized. SEM reveals the HA nano particles are homogeneously dispersed by twin- screw extrusion and the inter-particle spaces are penetrated with UHMWPE fibrils by swelling treatment. HRTEM image indicates the HA particles and UHMWPE are intimately contacted by mechanical interlocking. Compared with the unfilled UHMWPE, stiffness of the composite with the HA volume fraction 0.23 was significantly enhanced to 9 times without detriment of the yield strength and the ductility.

  4. Study on Chemical Cross-linking Modification of Hyaluronan and the Biocompatibility of its Derivatives

    Institute of Scientific and Technical Information of China (English)

    HU Guo-ying; LIU Xin; GU Han-qing

    2006-01-01

    Objective: Prepare cross-linked HA gels with higher mechanical stability,lower degradation velocity and desirable biocompatibility,so as to extend the usage of HA.Method: 1.Test molecular weight of HA (MrHA) by viscosimetry;2.Prepare cross-linked HA gels by DVS,GTA,DEC;3.Discuss the cross-linking and degradation procedure;4,evaluate the biocompatibility of the best HA gels.Results: The mechanical stability and durability to degradation of HA-DVS gels are superior to those of other gels,and when HA :DVS = 40:1 (g/g),at 35℃ and in 0.2M NaOH solution,the HA-DVS gel shows the best mechanical stability,and its cytotoxicity reaches class I,hemolysis ratio is lower than 5 %.Conclusion:Our HADVS gel can be used to prepare biologic scaffolds.

  5. Detection of multiple H3 receptor affinity states utilizing [3H]A-349821, a novel, selective, non-imidazole histamine H3 receptor inverse agonist radioligand.

    Science.gov (United States)

    Witte, David G; Yao, Betty Bei; Miller, Thomas R; Carr, Tracy L; Cassar, Steven; Sharma, Rahul; Faghih, Ramin; Surber, Bruce W; Esbenshade, Timothy A; Hancock, Arthur A; Krueger, Kathleen M

    2006-07-01

    1. A-349821 is a selective histamine H3 receptor antagonist/inverse agonist. Herein, binding of the novel non-imidazole H3 receptor radioligand [3H]A-349821 to membranes expressing native or recombinant H3 receptors from rat or human sources was characterized and compared with the binding of the agonist [3H]N--methylhistamine ([3H]NMH). 2. [3H]A-349821 bound with high affinity and specificity to an apparent single class of saturable sites and recognized human H3 receptors with 10-fold higher affinity compared to rat H3 receptors. [3H]A-349821 detected larger populations of receptors compared to [3H]NMH. 3. Displacement of [3H]A-349821 binding by H3 receptor antagonists/inverse agonists was monophasic, suggesting recognition of a single binding site, while that of H3 receptor agonists was biphasic, suggesting recognition of both high- and low-affinity H3 receptor sites. 4. pKi values of high-affinity binding sites for H3 receptor competitors utilizing [3H]A-349821 were highly correlated with pKi values obtained with [3H]NalphaMH, consistent with labelling of H3 receptors by [3H]A-349821. 5. Unlike assays utilizing [3H]NMH, addition of GDP had no effect on saturation parameters measured with [3H]A-349821, while displacement of [3H]A-349821 binding by the H3 receptor agonist histamine was sensitive to GDP. 6. In conclusion, [3H]A-349821 labels interconvertible high- and low-affinity states of the H3 receptor, and displays improved selectivity over imidazole-containing H3 receptor antagonist radioligands. [3H]A-349821 competition studies showed significant differences in the proportions and potencies of high- and low-affinity sites across species, providing new information about the fundamental pharmacological nature of H3 receptors.

  6. Monitoring bound HA1(H1N1) and HA1(H5N1) on freely suspended graphene over plasmonic platforms with infrared spectroscopy

    Science.gov (United States)

    Banerjee, Amrita; Chakraborty, Sumit; Altan-Bonnet, Nihal; Grebel, Haim

    2013-09-01

    Infrared (IR) spectroscopy provides fingerprinting of the energy and orientation of molecular bonds. The IR signals are generally weak and require amplification. Here we present a new plasmonic platform, made of freely suspended graphene, which was coating periodic metal structures. Only monolayer thick films were needed for a fast signal recording. We demonstrated unique IR absorption signals of bound proteins: these were the hemagglutinin area (HA1) of swine influenza (H1N1) and the avian influenza (H5N1) viruses bound to their respective tri-saccharides ligand receptors. The simplicity and sensitivity of such approach may find applications in fast monitoring of binding events.

  7. Isolation and identiifcation of Serratia marcescens Ha1 and herbicidal activity of Ha1‘pesta’ granular formulation

    Institute of Scientific and Technical Information of China (English)

    YANG Juan; WANG Wei; YANG Peng; TAO Bu; YANG Zheng; ZHANG Li-hui; DONG Jin-gao

    2015-01-01

    A total of 479 bacterial strains were isolated from brine (Bohai, Qinhuangdao City, Hebei Province, China). Bioassay results indicated that 4 strains named Ha1, Ha17, Ha38, and Ha384 had herbicidal activity. And strain Ha1 had the highest effective herbicidal activity. As a result, this study aims to identify strain Ha1, characterize its physiological and biological activities, evaluate the herbicidal activity of its metabolites, and develop a‘pesta’ formulation and assess its effectiveness on Digitaria sanguinalis. Ha1 was identiifed as Serratia marcescens based on 16S rDNA sequencing. This strain has a lfagel um, a diameter of 0.5 to 0.8μm, and a length of 0.9 to 2.0μm. The indole test shows positive results, and the catalase enzyme exhibits strong positive reactions. Results further showed that the inhibitory concentration (IC50) of the crude extracts to D. sanguinalis radicula and coleoptile were 3.332 and 2.828 mg mL–1, respectively. Both the suppression of D. sanguinalis and the cel viability of the Ha1 formulation in‘pesta’ were higher when stored at 4°C than at (25±2)°C. These results indi-cated that S. marcescens Ha1 can potential y be used as a biocontrol agent against D. sanguinalis.

  8. Võidupüha 8. mail? / Leonti Kährik

    Index Scriptorium Estoniae

    Kährik, Leonti

    2005-01-01

    Eesti peaks väärikalt tähistama võidupüha kui euroopalike demokraatlike väärtuste võitu natsismi ja fašismi üle. Lähtudes 1940. a. juunini Eestis kehtinud vööndiajast, võiks võidupüha tähistada 8. mail

  9. Võidupüha 8. mail? / Leonti Kährik

    Index Scriptorium Estoniae

    Kährik, Leonti

    2005-01-01

    Eesti peaks väärikalt tähistama võidupüha kui euroopalike demokraatlike väärtuste võitu natsismi ja fašismi üle. Lähtudes 1940. a. juunini Eestis kehtinud vööndiajast, võiks võidupüha tähistada 8. mail

  10. ha Platoni ordeni sai kaks saarlast / Isa Andreas

    Index Scriptorium Estoniae

    Andreas, Isa

    2009-01-01

    ha Platoni päeval päeval jagas metropoliit Stefanus püha Platoni ordeneid aktiivsetele kirikutegelastele ning pühitseti Tartu piiskopiks arhimandriit Eelija(Ojaperv) ja Pärnu ja Saare piiskopiks arhimandriit Aleksander (Hopjorski)

  11. ha Platoni ordeni sai kaks saarlast / Isa Andreas

    Index Scriptorium Estoniae

    Andreas, Isa

    2009-01-01

    ha Platoni päeval päeval jagas metropoliit Stefanus püha Platoni ordeneid aktiivsetele kirikutegelastele ning pühitseti Tartu piiskopiks arhimandriit Eelija(Ojaperv) ja Pärnu ja Saare piiskopiks arhimandriit Aleksander (Hopjorski)

  12. Preparation of bioactive porous HA/PCL composite scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, J.; Guo, L.Y.; Yang, X.B. [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Weng, J. [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)], E-mail: jweng@swjtu.cn

    2008-12-30

    Porous hydroxyapatite (HA) bioceramic scaffold has been widely attracted the attention to act as a three-dimensional (3D) template for cell adhesion, proliferation, differentiation and thus promoting bone and cartilage regeneration because of its osteoinduction. However, the porous bioceramic scaffold is fragile so that it is not suitable to be applied in clinic for bone repair or replacement. Therefore, it is significant to improve the mechanical property of porous HA bioceramics while the interconnected structure is maintained for tissue ingrowth in vivo. In the present research, a porous composite scaffold composed of HA scaffold and polycaprolactone (PCL) lining was fabricated by the method of polymer impregnating to produce HA scaffold coated with PCL lining. Subsequently, the composite scaffolds were deposited with biomimetic coating for improving the bioactivity. The HA/PCL composite scaffolds with improved mechanical property and bioactivity is expected to be a promising bone substitute in tissue engineering applications.

  13. Preparation of bioactive porous HA/PCL composite scaffolds

    Science.gov (United States)

    Zhao, J.; Guo, L. Y.; Yang, X. B.; Weng, J.

    2008-12-01

    Porous hydroxyapatite (HA) bioceramic scaffold has been widely attracted the attention to act as a three-dimensional (3D) template for cell adhesion, proliferation, differentiation and thus promoting bone and cartilage regeneration because of its osteoinduction. However, the porous bioceramic scaffold is fragile so that it is not suitable to be applied in clinic for bone repair or replacement. Therefore, it is significant to improve the mechanical property of porous HA bioceramics while the interconnected structure is maintained for tissue ingrowth in vivo. In the present research, a porous composite scaffold composed of HA scaffold and polycaprolactone (PCL) lining was fabricated by the method of polymer impregnating to produce HA scaffold coated with PCL lining. Subsequently, the composite scaffolds were deposited with biomimetic coating for improving the bioactivity. The HA/PCL composite scaffolds with improved mechanical property and bioactivity is expected to be a promising bone substitute in tissue engineering applications.

  14. Hypochlorite-mediated fragmentation of hyaluronan, chondroitin sulfates, and related N-acetyl glycosamines

    DEFF Research Database (Denmark)

    Rees, Martin D; Hawkins, Clare Louise; Davies, Michael Jonathan

    2003-01-01

    Myeloperoxidase released from activated phagocytes reacts with H(2)O(2) in the presence of chloride ions to give hypochlorous acid. This oxidant has been implicated in the fragmentation of glycosaminoglycans, such as hyaluronan and chondroitin sulfates. In this study it is shown that reaction......, product formation via this mechanism is near quantitative with respect to chloramide loss. Analogous reactions with the glycosaminoglycans result in selective fragmentation at disaccharide intervals, as evidenced by the formation of "ladders" on gels; this selectivity is less marked under atmospheric...... oxygen concentrations than under anoxic conditions, due to competing peroxyl radical reactions. As the extracellular matrix plays a key role in mediating cell adhesion, growth, activation, and signaling, such HOCl-mediated glycosaminoglycan fragmentation may play a key role in disease progression...

  15. Selective Targeting and Restrictive Damage for Nonspecific Cells by Pulsed Laser-Activated Hyaluronan-Gold Nanoparticles.

    Science.gov (United States)

    Rau, Lih-Rou; Tsao, Shu-Wei; Liaw, Jiunn-Woei; Tsai, Shiao-Wen

    2016-08-08

    Herein, we describe an approach that immobilizes low-molecular-weight hyaluronic acid (low-MW HA) on the surface of gold nanoparticles (GNPs), which can serve as a cellular probe and photodamage media, to evaluate the selectivity and efficiency of HA-based GNPs (HGNPs) as a mediator of laser-induced photothermal cell damage. In addition, it is known that solid tumors contain a higher content of low-MW HA than normal tissues. Thus, we used low-MW HA rather than high-MW HA used in other studies. In the present study, we conjugated low-MW HA, which is a linear polysaccharide with a disaccharide repeat unit, to prevent a reduction of the ligand-receptor binding efficiency in contrast to the conjugation of protein or peptides, which have unique three-dimensional structures. Three cell lines-MDA-MB-435 S (with CD44), MDA-MB-453 and NIH/3T3 (both are without CD44)-were investigated in the study, and qualitative observations were conducted by dark-field microscopy and laser scanning confocal microscopy (LSCM). In addition, quantitative measurements calculated using inductively coupled plasma emissions were taken for comparison. Our results showed that within the same treatment time, the uptake dosage of HGNPs by the MDA-MB-435 S cells was higher than that by the MDA-MB-453 and NIH 3T3 cells. Meanwhile, HGNPs uptake by the untreated MDA-MB-435 S cells was higher than that of MDA-MB-435 S cells with CD44 blocked by antibodies or silencing CD44 expression. This result implies that receptor-mediated endocytosis can enhance the cellular uptake of HGNPs. In addition, when exposed to a low-power pulsed laser, the former cell morphologies showed a more laser-induced giant plasma membrane vesicles (GPMV) than the latter morphologies. Therefore, this study utilized the specific photothermal property of HA-modified GNPs with laser-induced blebs to create a possible new method for medical applications.

  16. Registration of two confection sunflower germplasm Lines, HA-R10 and HA-R11, Resistant to sunflower rust

    Science.gov (United States)

    Two confection sunflower (Helianthus annuus L.) germplasm lines, HA-R10 (Reg. No.xxx, PI670043) and HA-R11 (Reg. No.xxx, PI670044) were developed by the USDA-ARS Sunflower and Plant Biology Research Unit in collaboration with the North Dakota Agricultural Experiment Station and released December, 20...

  17. Registration of two double rust resistant germplasms, HA-R12 and HA-R13 for confection sunflower

    Science.gov (United States)

    The confection sunflower (Helianthus annuus L.) germplasms HA-R12 (Reg. No. ______, PI 673104) and HA-R13 (Reg. No. ______, PI 673105) were developed by the USDA-ARS, Sunflower and Plant Biology Research Unit in collaboration with the North Dakota Agricultural Experiment Station, and released in Jul...

  18. Formation of a solar Ha filament from orphan penumbrae

    CERN Document Server

    Buehler, D; van Noort, M; Solanki, S K

    2016-01-01

    The formation of an Ha filament in active region (AR) 10953 is described. Observations from the Solar Optical Telescope (SOT) aboard the Hinode satellite starting on 27th April 2007 until 1st May 2007 were analysed. 20 scans of the 6302A Fe I line pair recorded by SOT/SP were inverted using the SPINOR code. The inversions were analysed together with SOT/BFI G-band and Ca II H and SOT/NFI Ha observations. Following the disappearance of an initial Ha filament aligned along the polarity inversion line (PIL) of the AR, a new Ha filament formed in its place some 20 hours later, which remained stable for at least 1.5 days. The creation of the new Ha filament was driven by the ascent of horizontal magnetic fields from the photosphere into the chromosphere at three separate locations along the PIL. The magnetic fields at two of these locations were situated directly underneath the initial Ha filament and formed orphan penumbrae already aligned along the Ha filament channel. The 700 G orphan penumbrae were stable and ...

  19. The Disease-Modifying Effects of Hyaluronan in the Osteoarthritic Disease State

    Directory of Open Access Journals (Sweden)

    Mathew A Nicholls

    2017-08-01

    Full Text Available Hyaluronic acid (HA has been a treatment modality for patients with knee osteoarthritis (OA for many years now. Since HA was first introduced for the treatment of painful knee OA, much has been elucidated regarding both the etiology of this disease and the mechanisms by which HA may mitigate joint pain and tissue destruction. The objectives of this article are to (1 describe the etiology and pathophysiology of OA including both what is known about the genetics and biochemistry, (2 describe the role of HA on disease progression, (3 detail the antinociceptive and anti-inflammatory actions of HA in OA, and (4 present evidence of disease-modifying effects of HA in the preservation and restoration of the extracellular matrix. These data support that HA is not only just a simple device used for viscosupplementation but also a biologically active molecule that can affect the physiology of articular cartilage.

  20. Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of Hyaluronan-CD44-CD147 Interactions

    Science.gov (United States)

    2015-09-01

    and emmprin regulate lactate efflux and membrane localization of monocarboxylate transporters in human breast carcinoma cells. Cancer Res. 69:1293...1 AWARD NUMBER: W81XWH-12-1-0268 TITLE: Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of Hyaluronan-CD44-CD147...3. DATES COVERED 1 July, 2012 – 30 June, 2015 4. TITLE AND SUBTITLE Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of

  1. Cytocompatible in situ forming chitosan/hyaluronan hydrogels via a metal-free click chemistry for soft tissue engineering.

    Science.gov (United States)

    Fan, Ming; Ma, Ye; Mao, Jiahui; Zhang, Ziwei; Tan, Huaping

    2015-07-01

    Injectable hydrogels are important cell scaffolding materials for tissue engineering and regenerative medicine. Here, we report a new class of biocompatible and biodegradable polysaccharide hydrogels derived from chitosan and hyaluronan via a metal-free click chemistry, without the addition of copper catalyst. For the metal-free click reaction, chitosan and hyaluronan were modified with oxanorbornadiene (OB) and 11-azido-3,6,9-trioxaundecan-1-amine (AA), respectively. The gelation is attributed to the triazole ring formation between OB and azido groups of polysaccharide derivatives. The molecular structures were verified by FT-IR spectroscopy and elemental analysis, giving substitution degrees of 58% and 47% for chitosan-OB and hyaluronan-AA, respectively. The in vitro gelation, morphologies, equilibrium swelling, compressive modulus and degradation of the composite hydrogels were examined. The potential of the metal-free hydrogel as a cell scaffold was demonstrated by encapsulation of human adipose-derived stem cells (ASCs) within the gel matrix in vitro. Cell culture showed that this metal-free hydrogel could support survival and proliferation of ASCs. A preliminary in vivo study demonstrated the usefulness of the hydrogel as an injectable scaffold for adipose tissue engineering. These characteristics provide a potential opportunity to use the metal-free click chemistry in preparation of biocompatible hydrogels for soft tissue engineering applications. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Hyaluronan and Fibrin Biomaterial as Scaffolds for Neuronal Differentiation of Adult Stem Cells Derived from Adipose Tissue and Skin

    Directory of Open Access Journals (Sweden)

    Chiara Gardin

    2011-10-01

    Full Text Available Recently, we have described a simple protocol to obtain an enriched culture of adult stem cells organized in neurospheres from two post-natal tissues: skin and adipose tissue. Due to their possible application in neuronal tissue regeneration, here we tested two kinds of scaffold well known in tissue engineering application: hyaluronan based membranes and fibrin-glue meshes. Neurospheres from skin and adipose tissue were seeded onto two scaffold types: hyaluronan based membrane and fibrin-glue meshes. Neurospheres were then induced to acquire a glial and neuronal-like phenotype. Gene expression, morphological feature and chromosomal imbalance (kariotype were analyzed and compared. Adipose and skin derived neurospheres are able to grow well and to differentiate into glial/neuron cells without any chromosomal imbalance in both scaffolds. Adult cells are able to express typical cell surface markers such as S100; GFAP; nestin; βIII tubulin; CNPase. In summary, we have demonstrated that neurospheres isolated from skin and adipose tissues are able to differentiate in glial/neuron-like cells, without any chromosomal imbalance in two scaffold types, useful for tissue engineering application: hyaluronan based membrane and fibrin-glue meshes.

  3. Electrochemical Properties of HA Coated Titanium Dioxide Nanotubes.

    Science.gov (United States)

    Kang, Kyungho; Zakiyuddin, Ahmad; Lee, Kwangmin

    2016-02-01

    CP Grade II titanium was first anodized in order to form TiO2 nanotubes, and then the TiO2 nano- tubes were coated with hydroxyapatite using the sol-gel method. The electrochemical properties of pure Ti, anodized TiO2 nanotubes, and HA-coated TiO2 nanotubes were investigated using poten- tiodynamic polarization and impedance tests. The sol-gel-coated HA nanoparticles were observed to sufficiently penetrate into the TiO2 nanotubes, and the polarization resistance of the HA-coated titanium nanotubes was higher than that of those that had just been anodized. In conclusion, the HA coating on the TiO2 nanotubes provides improved electrochemical properties and can be effective in overcoming the negative influence of passive TiO2 films.

  4. Haïti et l'anthropologie

    OpenAIRE

    2008-01-01

    Le premier numéro de la nouvelle série de GRADHIVA est consacré à l’anthropologie en Haïti : ses origines, son rôle, ses évolutions récentes, son devenir. Ce numéro double de 272 pages, illustré de nombreux clichés, évoque les rapports étroits entre l’anthropologie et la culture multiforme d’Haïti, à travers l’oeuvre de peintres, d’historiens, d’écrivains, ou d’ethnologues haïtiens. Le dossier analyse le développement d’une anthropologie haïtienne nécessairement liée à la question raciale et ...

  5. A-Ha. Drum'n'bassi supernimi FABIO

    Index Scriptorium Estoniae

    2002-01-01

    7.sept. annab norra menukaim popansambel A-Ha Tallinnas Lauluväljakul kontserdi, kus presenteerib ka oma viimast albumit "Lifelines". 14. sept.tuleb drum'n'bassi spetsialist Fabio Tallinna üritusele Circulation

  6. Adhesive strength of hydroxyl apatite(HA coating and biomechanics behavior of HA-coated prosthesis:an experimental study

    Directory of Open Access Journals (Sweden)

    Tian-yang ZHANG

    2011-05-01

    Full Text Available Objective To explore the influence of adhesive strength of hydroxyapatite(HA coating on the post-implantation stability of HA-coated prosthesis.Methods The adhesive strength and biomechanics behavior of HA coating were studied by histopathological observation,material parameters and biomechanical testing,the titanium(Ti-coated prosthesis was employed as control.Results Scratch test showed that the adhesive strength of HA coating was significantly lower than that of Ti coating(P < 0.01.Histopathological examination and bone morphometry showed that,at the early stage of prosthesis implantation,the bony growth around HA-coated prosthesis was significantly higher than that around Ti-coated prosthesis(P < 0.01,but the ultimate shear strength of HA-coated prosthesis was much lower than that of Ti-coated prosthesis(P < 0.01.After the push-out test with prosthesis,histopathological observation showed that there were accumulations of clump-and strip-like granular residues on the surface of bones that newly grew around the HA-coated prosthesis,and surface energy-dispersive X-ray spectroscopy(EDX analysis also confirmed that the shear stress induced HA decohesion from the substrate of prosthesis.Conclusions Although HA coating showed a satisfactory effect on early bone formation and prosthetic stability,due to the deficiencies of adhesive strength,the early stability of prosthesis may be gradually destroyed by the shear loads of human body and coating degradation.

  7. Molecular dynamics simulation of mechanical properties and surface interaction for HA/PLA%HA/PLA复合材料界面相互作用及其力学性能的MD模拟

    Institute of Scientific and Technical Information of China (English)

    魏庆华; 汪焰恩; 杨明明; 魏生民

    2013-01-01

    基于HA/PLA复合材料可以在很大程度上实现 HA与PLA两者的优势互补,有望成为一种理想的骨替换材料。运用分子动力学(MD)方法,从分子理论的角度研究了羟基磷灰石(HA)的3个晶面(001)、(100)、(110)分别与聚乳酸(PLA)相互作用后混合体系的结合能,并对(110)晶面径向分布函数和力学性能进行了计算分析。结果表明,3晶面所对应结合能大小为 HA(110)>HA(100)>HA(001);其相互作用主要源自PLA中的O 原子分别与HA中的H 原子形成的氢键以及 Oa1-Ca之间形成了离子键;PLA 组分能够对 HA的力学性能起到明显的加强作用,且 HA/PLA混合体系在各个方向的力学性能较单组分 HA更为接近,从而克服了因材料各向异性而导致的缺陷。%HA/PLA composite material can realize the complementary advantages in the very great degree,was expected to become an ideal bone replacement material.In this paper,molecular dynamics simulation was ap-plied to investigate the binding energy of PLA on HA crystallographic planes (001),(100)and (110),and then the mechanical properties and radial distribution function of the HA(110)/PLA mixed system were calculated and analyzed.The results show that HA (110)has the highest binding energy with these polymers because of its higher planar atom density than that of HA (001)and (100).By calculating the radial distribution function, the interface interaction and its essence of the HA(110)/PLA were elucidated.There was a strong interaction between HA crystallographic plane (110)and PLA,it was mainly derived from the hydrogen bonds between O atoms of PLA and H atoms in HA crystal.The PLA component plays a significant role in strengthening the mechanical properties of HA.And the mechanical properties of HA/PLA in each direction was closer than sin-gle component HA,thus overcoming the defects caused due to the anisotropy of the material.

  8. Osteoblast interaction with laser cladded HA and SiO{sub 2}-HA coatings on Ti-6Al-4V

    Energy Technology Data Exchange (ETDEWEB)

    Yang Yuling [Department of Physics, Northeastern University, Shenyang 110004 (China); Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Serpersu, Kaan [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); He Wei, E-mail: whe5@utk.edu [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Paital, Sameer R. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Dahotre, Narendra B. [Department of Materials Science and Engineering, University of North Texas, Denton, TX 76207 (United States)

    2011-12-01

    In order to improve the bioactivity and biocompatibility of titanium endosseous implants, the morphology and composition of the surfaces were modified. Polished Ti-6Al-4V substrates were coated by a laser cladding process with different precursors: 100 wt.% HA and 25 wt.% SiO{sub 2}-HA. X-ray diffraction of the laser processed samples showed the presence of CaTiO{sub 3}, Ca{sub 3}(PO{sub 4}){sub 2}, and Ca{sub 2}SiO{sub 4} phases within the coatings. From in vitro studies, it was observed that compared to the unmodified substrate all laser cladded samples presented improved cellular interactions and bioactivity. The samples processed with 25 wt.% SiO{sub 2}-HA precursor showed a significantly higher HA precipitation after immersion in simulated body fluid than 100 wt.% HA precursor and titanium substrates. The in vitro biocompatibility of the laser cladded coatings and titanium substrate was investigated by culturing of mouse MC3T3-E1 pre-osteoblast cell line and analyzing the cell viability, cell proliferation, and cell morphology. A significantly higher cell attachment and proliferation rate were observed for both laser cladded 100 wt.% HA and 25 wt.% SiO{sub 2}-HA samples. Compared to 100 wt.% HA sample, 25 wt.% SiO{sub 2}-HA samples presented a slightly improved cellular interaction due to the addition of SiO{sub 2}. The staining of the actin filaments showed that the laser cladded samples induced a normal cytoskeleton and well-developed focal adhesion contacts. Scanning electron microscopic image of the cell cultured samples revealed better cell attachment and spreading for 25 wt.% SiO{sub 2}-HA and 100 wt.% HA coatings than titanium substrate. These results suggest that the laser cladding process improves the bioactivity and biocompatibility of titanium. The observed biological improvements are mainly due to the coating induced changes in surface chemistry and surface morphology. Highlights: {yields} Laser cladding of Ti alloys with bioceramics creates new

  9. High molecular weight hyaluronan for treatment of chronic shoulder pain associated with glenohumeral arthritis

    Directory of Open Access Journals (Sweden)

    Weil AJ

    2011-07-01

    Full Text Available Arnold J WeilNon-Surgical Orthopedics PC, Marietta, GA, USABackground: There is insufficient evidence to determine whether intra-articular injections may be effective for treatment of glenohumeral osteoarthritis. Euflexxa® (high molecular weight hyaluronate, a bioengineered high molecular weight hyaluronan, has been shown to be a safe and effective treatment for patients with knee osteoarthritis. There is also support for the use of hyaluronate injection for the treatment of chronic shoulder pain associated with osteoarthritis or rotator cuff damage. This small-scale exploratory study was conducted to evaluate the safety and efficacy of high molecular weight hyaluronate for the treatment of chronic shoulder pain associated with osteoarthritis.Methods: Subjects with glenohumeral osteoarthritis and chronic pain (n = 27 received one injection per week for 3 weeks of high molecular weight hyaluronate and were assessed for changes in pain (100 mm visual analog scale [VAS], range of motion, and the subject’s and physician’s global assessment over 26 weeks. Subjects were also assessed for pain, stiffness, and physical functioning using the Western Ontario and McMaster Universities Arthritis Index (WOMAC. Finally, responses were evaluated using modified Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT-Osteoarthritis Research Society International (OARSI Proposition D criteria. Safety was assessed by recording adverse events.Results: High molecular weight hyaluronate significantly improved pain (VAS, WOMAC, range of motion, stiffness, and physical functioning scores; 77.8% of subjects were rated as having an OMERACT-OARSI Proposition D high response. There were no serious adverse events, and none were considered to be related to treatment.Conclusion: Treatment with high molecular weight hyaluronate improves pain, stiffness, and range of motion, and may have an acceptable safety and tolerability profile. A randomized, double

  10. Prospects of HA-Based Universal Influenza Vaccine

    Directory of Open Access Journals (Sweden)

    Anwar M. Hashem

    2015-01-01

    Full Text Available Current influenza vaccines afford substantial protection in humans by inducing strain-specific neutralizing antibodies (Abs. Most of these Abs target highly variable immunodominant epitopes in the globular domain of the viral hemagglutinin (HA. Therefore, current vaccines may not be able to induce heterosubtypic immunity against the divergent influenza subtypes. The identification of broadly neutralizing Abs (BnAbs against influenza HA using recent technological advancements in antibody libraries, hybridoma, and isolation of single Ab-secreting plasma cells has increased the interest in developing a universal influenza vaccine as it could provide life-long protection. While these BnAbs can serve as a source for passive immunotherapy, their identification represents an important step towards the design of such a universal vaccine. This review describes the recent advances and approaches used in the development of universal influenza vaccine based on highly conserved HA regions identified by BnAbs.

  11. CILogon-HA. Higher Assurance Federated Identities for DOE Science

    Energy Technology Data Exchange (ETDEWEB)

    Basney, James [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-08-01

    The CILogon-HA project extended the existing open source CILogon service (initially developed with funding from the National Science Foundation) to provide credentials at multiple levels of assurance to users of DOE facilities for collaborative science. CILogon translates mechanism and policy across higher education and grid trust federations, bridging from the InCommon identity federation (which federates university and DOE lab identities) to the Interoperable Global Trust Federation (which defines standards across the Worldwide LHC Computing Grid, the Open Science Grid, and other cyberinfrastructure). The CILogon-HA project expanded the CILogon service to support over 160 identity providers (including 6 DOE facilities) and 3 internationally accredited certification authorities. To provide continuity of operations upon the end of the CILogon-HA project period, project staff transitioned the CILogon service to operation by XSEDE.

  12. Basonuclin regulates a subset of ribosomal RNA genes in HaCaT cells.

    Directory of Open Access Journals (Sweden)

    Shengliang Zhang

    Full Text Available Basonuclin (Bnc1, a cell-type-specific ribosomal RNA (rRNA gene regulator, is expressed mainly in keratinocytes of stratified epithelium and gametogenic cells of testis and ovary. Previously, basonuclin was shown in vitro to interact with rRNA gene (rDNA promoter at three highly conserved sites. Basonuclin's high affinity binding site overlaps with the binding site of a dedicated and ubiquitous Pol I transcription regulator, UBF, suggesting that their binding might interfere with each other if they bind to the same promoter. Knocking-down basonuclin in mouse oocytes eliminated approximately one quarter of RNA polymerase I (Pol I transcription foci, without affecting the BrU incorporation of the remaining ones, suggesting that basonuclin might regulate a subset of rDNA. Here we show, via chromatin immunoprecipitation (ChIP, that basonuclin is associated with rDNA promoters in HaCaT cells, a spontaneously established human keratinocyte line. Immunoprecipitation data suggest that basonuclin is in a complex that also contains the subunits of Pol I (RPA194, RPA116, but not UBF. Knocking-down basonuclin in HaCaT cells partially impairs the association of RPA194 to rDNA promoter, but not that of UBF. Basonuclin-deficiency also reduces the amount of 47S pre-rRNA, but this effect can be seen only after cell-proliferation related rRNA synthesis has subsided at a higher cell density. DNA sequence of basonuclin-bound rDNA promoters shows single nucleotide polymorphisms (SNPs that differ from those associated with UBF-bound promoters, suggesting that basonuclin and UBF interact with different subsets of promoters. In conclusion, our results demonstrate basonuclin's functional association with rDNA promoters and its interaction with Pol I in vivo. Our data also suggest that basonuclin-Pol I complex transcribes a subset of rDNA.

  13. Effect of Water-Glass Coating on HA and HA-TCP Samples for MSCs Adhesion, Proliferation, and Differentiation

    Directory of Open Access Journals (Sweden)

    Indu Bajpai

    2016-01-01

    Full Text Available Ca-P and silicon based materials have become very popular as bone tissue engineering materials. In this study, water-glass (also known as sodium silicate glass was coated on sintered hydroxyapatite (HA and HA-TCP (TCP stands for tricalcium phosphate samples and subsequently heat-treated at 600°C for 2 hrs. X-rays diffraction showed the presence of β- and α-TCP phases along with HA in the HA-TCP samples. Samples without coating, with water-glass coating, and heat-treated after water-glass coating were used to observe the adhesion and proliferation response of bone marrow derived-mesenchymal stem cells (MSCs. Cell culture was carried out for 4 hrs, 1 day, and 7 days. Interestingly, all samples showed similar response for cell adhesion and proliferation up to 7-day culture but fibronectin, E-cadherin, and osteogenic differentiation related genes (osteocalcin and osteopontin were significantly induced in heat-treated water-glass coated HA-TCP samples. A water-glass coating on Ca-P samples was not found to influence the cell proliferation response significantly but activated some extracellular matrix genes and induced osteogenic differentiation in the MSCs.

  14. Circular Halbach array for fast magnetic separation of hyaluronan-expressing tissue progenitors.

    Science.gov (United States)

    Joshi, Powrnima; Williams, P Stephen; Moore, Lee R; Caralla, Tonya; Boehm, Cynthia; Muschler, George; Zborowski, Maciej

    2015-10-06

    Connective tissue progenitors (CTPs) are a promising therapeutic agent for bone repair. Hyaluronan, a high molecular mass glycosaminoglycan, has been shown by us to be a suitable biomarker for magnetic separation of CTPs from bone marrow aspirates in a canine model. For the therapy to be applicable in humans, the magnetic separation process requires scale-up without compromising the viability of the cells. The scaled-up device presented here utilizes a circular Halbach array of diametrically magnetized, cylindrical permanent magnets. This allows precise control of the magnetic field gradient driving the separation, with theoretical analysis favoring a hexapole field. The separation vessel has the external diameter of a 50 mL conical centrifuge tube and has an internal rod that excludes cells from around the central axis. The magnet and separation vessel (collectively dubbed the hexapole magnet separator or HMS) was tested on four human and four canine bone marrow aspirates. Each CTP-enriched cell product was tested using cell culture bioassays as surrogates for in vivo engraftment quality. The magnetically enriched cell fractions showed statistically significant, superior performance compared to the unenriched and depleted cell fractions for all parameters tested, including CTP prevalence (CTPs per 10(6) nucleated cells), proliferation by colony forming unit (CFU) counts, and differentiation by staining for the presence of osteogenic and chondrogenic cells. The simplicity and speed of the HMS operation could allow both CTP isolation and engraftment during a single surgical procedure, minimizing trauma to patients and lowering cost to health care providers.

  15. Successful transplantation of human hepatic stem cells with restricted localization to liver using hyaluronan grafts.

    Science.gov (United States)

    Turner, Rachael A; Wauthier, Eliane; Lozoya, Oswaldo; McClelland, Randall; Bowsher, James E; Barbier, Claire; Prestwich, Glenn; Hsu, Edward; Gerber, David A; Reid, Lola M

    2013-02-01

    Cell therapies are potential alternatives to organ transplantation for liver failure or dysfunction but are compromised by inefficient engraftment, cell dispersal to ectopic sites, and emboli formation. Grafting strategies have been devised for transplantation of human hepatic stem cells (hHpSCs) embedded into a mix of soluble signals and extracellular matrix biomaterials (hyaluronans, type III collagen, laminin) found in stem cell niches. The hHpSCs maintain a stable stem cell phenotype under the graft conditions. The grafts were transplanted into the livers of immunocompromised murine hosts with and without carbon tetrachloride treatment to assess the effects of quiescent versus injured liver conditions. Grafted cells remained localized to the livers, resulting in a larger bolus of engrafted cells in the host livers under quiescent conditions and with potential for more rapid expansion under injured liver conditions. By contrast, transplantation by direct injection or via a vascular route resulted in inefficient engraftment and cell dispersal to ectopic sites. Transplantation by grafting is proposed as a preferred strategy for cell therapies for solid organs such as the liver.

  16. Genetic variation in hyaluronan metabolism loci is associated with plasma plasminogen activator inhibitor-1 concentration.

    Science.gov (United States)

    Lanktree, Matthew B; Johansen, Christopher T; Anand, Sonia S; Davis, A Darlene; Miller, Ruby; Yusuf, Salim; Hegele, Robert A

    2010-09-23

    Elevated plasma plasminogen activator inhibitor-1 (PAI-1) concentration is associated with cardiovascular disease risk. PAI-1 is the primary inhibitor of fibrinolysis within both the circulation and the arterial wall, playing roles in both atherosclerosis and thrombosis. To define the heritable component, subjects within the population-based SHARE (Study of Health Assessment and Risk in Ethnic groups) and SHARE-AP (Study of Health Assessment and Risk Evaluation in Aboriginal Peoples) studies, composed of Canadians of South Asian (n = 298), Chinese (n = 284), European (n = 227), and Aboriginal (n = 284) descent, were genotyped using the gene-centric Illumina HumanCVD BeadChip. After imputation, more than 150,000 single nucleotide polymorphisms (SNPs) in more than 2000 loci were tested for association with plasma PAI-1 concentration. Marginal association was observed with the PAI-1 locus itself (SERPINE1; P HABP2, HSPA1A, HYAL1, MBTPS1, TARP) were associated with PAI-1 concentration at a P HABP2) and hyaluronoglucosaminidase 1 (HYAL1), play key roles in hyaluronan metabolism, providing genetic evidence to link these pathways.

  17. Läkaköha - aktuaalne uurimisteema / Marje Oona

    Index Scriptorium Estoniae

    Oona, Marje, 1963-

    2012-01-01

    TÜ peremeditsiini õppetooli töötajate poolt algatatud uurimistööst, mille eesmärgiks on uurida Bordetella spp. infektsioonide epidemioloogiat, molekulaargeneetikat ja kliinilisi eripärasid ning selgitada läkaköha sagedasema diagnsimise põhjusi Eestis

  18. Läkaköha - aktuaalne uurimisteema / Marje Oona

    Index Scriptorium Estoniae

    Oona, Marje, 1963-

    2012-01-01

    TÜ peremeditsiini õppetooli töötajate poolt algatatud uurimistööst, mille eesmärgiks on uurida Bordetella spp. infektsioonide epidemioloogiat, molekulaargeneetikat ja kliinilisi eripärasid ning selgitada läkaköha sagedasema diagnsimise põhjusi Eestis

  19. Hyaluronan/Tannic Acid Nanoparticles Via Catechol/Boronate Complexation as a Smart Antibacterial System.

    Science.gov (United States)

    Montanari, Elita; Gennari, Arianna; Pelliccia, Maria; Gourmel, Charlotte; Lallana, Enrique; Matricardi, Pietro; McBain, Andrew J; Tirelli, Nicola

    2016-12-01

    Nanoparticles based on hyaluronic acid (HA) are designed to deliver tannic acid (TA) as an antimicrobial agent. The presence of HA makes these particles potentially useful to target bacteria that colonize cells presenting HA membrane receptors (e.g. CD44), such as macrophages. HA bearing 3-aminophenyl boronic acid groups (HA-APBA) is reacted with TA, yielding nanoparticles with a size that decreases with decreasing HA molecular weight (e.g. 200 nm for 44 kDa, 400 nm for 737 kDa). The boronate esters make the nanoparticles stable at physiological pH, but their hydrolysis in an acidic environment (pH = 5) leads to swelling/solubilization, therefore potentially allowing TA release in endosomal compartments. We have assessed the nanoparticle toxicity profile (on RAW 264.7 macrophages) and their antimicrobial activity (on E. coli and on both methicillin-sensitive and -resistant S. aureus). The antibacterial effect of HA-APBA/TA nanoparticles was significantly higher than that of TA alone, and has very similar activity to TA coformulated with a reducing agent (ascorbic acid), which indicates both the nanoparticles to protect TA catechols from oxidation, and the effective release of TA after nanoparticle internalization. Therefore, there is potential for these nanoparticles to be used in stable, effective, and potentially targetable nanoparticle-based antimicrobial formulations.

  20. Effects of bound versus soluble pentosan polysulphate in PEG/HA-based hydrogels tailored for intervertebral disc regeneration.

    Science.gov (United States)

    Frith, Jessica E; Menzies, Donna J; Cameron, Andrew R; Ghosh, P; Whitehead, Darryl L; Gronthos, S; Zannettino, Andrew C W; Cooper-White, Justin J

    2014-01-01

    Previous reports in the literature investigating chondrogenesis in mesenchymal progenitor cell (MPC) cultures have confirmed the chondro-inductive potential of pentosan polysulphate (PPS), a highly sulphated semi-synthetic polysaccharide, when added as a soluble component to culture media under standard aggregate-assay conditions or to poly(ethylene glycol)/hyaluronic acid (PEG/HA)-based hydrogels, even in the absence of inductive factors (e.g. TGFβ). In this present study, we aimed to assess whether a 'bound' PPS would have greater activity and availability over a soluble PPS, as a media additive or when incorporated into PEG/HA-based hydrogels. We achieved this by covalently pre-binding the PPS to the HA component of the gel (forming a new molecule, HA-PPS). We firstly investigated the activity of HA-PPS compared to free PPS, when added as a soluble factor to culture media. Cell proliferation, as determined by CCK8 and EdU assay, was decreased in the presence of either bound or free PPS whilst chondrogenic differentiation, as determined by DMMB assay and histology, was enhanced. In all cases, the effect of the bound PPS (HA-PPS) was more potent than that of the unbound form. These results alone suggest wider applications for this new molecule, either as a culture supplement or as a coating for scaffolds targeted at chondrogenic differentiation or maturation. We then investigated the incorporation of HA-PPS into a PEG/HA-based hydrogel system, by simply substituting some of the HA for HA-PPS. Rheological testing confirmed that incorporation of either HA-PPS or PPS did not significantly affect gelation kinetics, final hydrogel modulus or degradation rate but had a small, but significant, effect on swelling. When encapsulated in the hydrogels, MPCs retained good viability and rapidly adopted a rounded morphology. Histological analysis of both GAG and collagen deposition after 21 days showed that the incorporation of the bound-PPS into the hydrogel resulted in

  1. The Structure of the Neurotoxin- Associated Protein HA33/A from Clostridium botulinum Suggests a Reoccurring Beta-Trefoil Fold in the Progenitor Toxin Complex

    Science.gov (United States)

    2007-11-02

    sequence similarity to the b-trefoil- containing binding domains of BoNT/A and tetanus neurotoxin (TeNT) from Clostridium tetani with sequence...doi:10.1016/j.jmb.2004.12.039 J. Mol. Biol. (2005) 346, 1083–1093The Structure of the Neurotoxin-associated Protein HA33/A from Clostridium botulinum...correspond stevens@scripps.eduThe hemagglutinating protein HA33 from Clostridium botulinum is associated with the large botulinum neurotoxin secreted

  2. Systemic administration of high-molecular weight hyaluronan stimulates wound healing in genetically diabetic mice.

    Science.gov (United States)

    Galeano, Mariarosaria; Polito, Francesca; Bitto, Alessandra; Irrera, Natasha; Campo, Giuseppe M; Avenoso, Angela; Calò, Margherita; Lo Cascio, Patrizia; Minutoli, Letteria; Barone, Mauro; Squadrito, Francesco; Altavilla, Domenica

    2011-07-01

    Hyaluronic acid (HA), an essential component of the extracellular matrix, is an efficient space filler that maintains hydration, serves as a substrate for assembly of proteoglycans and is involved in wound healing. Although numerous pieces of evidence demonstrate beneficial effects in promoting wound healing in diabetes, a systemic approach has never been tested. We used an incisional wound healing model in genetically diabetic mice to test the effects of systemic injection of HA. Diabetic (n=56) and normoglycemic (n=56) mice were subjected to incision and randomized (8 groups of 7 animals each) to receive HA at different doses, 7.5, 15 and 30mg/kg/i.p., or vehicle (0.9% NaCl solution) for 12days. At the end of the experiment animals were sacrificed and skin wounds were excised for histological, biochemical and molecular analysis. Histology revealed that the most effective dose to improve wound repair and angiogenesis in diabetic mice was 30mg/kg. Furthermore HA injection (30mg/kg) improved the altered healing pattern in diabetic animals, increased skin remodeling proteins TGF-β and transglutaminase-II and restored the altered expression of cyclin B1/Cdc2 complex. Evaluation of skin from diabetic animals injected with HA revealed also an increase in HA content, suggesting that systemic injection may be able to restore the reduced intracellular HA pool of diabetic mice. Finally HA markedly improved skin mechanical properties. These promising results, if confirmed in a clinical setting, may improve the care and management of diabetic patients.

  3. Microvascular maturity elicited in tissue treated with cytokine-loaded hyaluronan-based hydrogels.

    Science.gov (United States)

    Hosack, Luke W; Firpo, Matthew A; Scott, J Anna; Prestwich, Glenn D; Peattie, Robert A

    2008-05-01

    Hydrogels composed of crosslinked, chemically modified hyaluronic acid (HA), gelatin (Gtn) and heparin (Hp) were preloaded with vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), keratinocyte growth factor (KGF) or platelet derived growth factor (PDGF) either individually or in combination with VEGF and implanted into the Balb/c mouse ear pinna. At 7 and 14 days post-surgery, elicited vascular maturity levels were quantified using immunohistochemical (IHC) staining techniques and reported as a vascular maturity index (VMI). At both time points, it was discovered that the dual cytokine combinations elicited greater maturity levels than that of cytokine administered individually. For example, VEGF and KGF-containing HA:Hp implants at day 7 yielded VMI values of -0.1375 and -0.092, respectively, whereas their combination resulted in a VMI of 0.176 (pVMI (VEGF+KGF), whereas four of the seven HA:Hp cases yielded positive VMI values at day 14, indicating a sustained maturity response. The same general trends were found to exist in tissue treated with HA:Hp:Gtn experimental implants. Differences in elicited maturity also existed between tissue treated with HA:Hp and HA-containing hydrogels (VMI=0.176 for HA:Hp-VEGF+KGF vs. -0.064 for HA-VEGF+KGF, p<0.012), and these differences are thought to result from differences in characteristic cytokine release rates. This result also suggests that the presentation of multiple growth factors (GFs) on immobilized Hp may actively contribute to cytokine related signal transduction, a characteristic that may be exploited in the future to improve the efficacy of cytokine-loaded implants towards tissue regeneration therapeutic strategies.

  4. HA03 as an Iranian Candidate Concealed Antigen for Vaccination against Hyalomma anatolicum anatolicum: Comparative Structural and In silico Studies

    Directory of Open Access Journals (Sweden)

    Mohammadi, A.

    2013-12-01

    Full Text Available In the last decades researchers had focused on developing a vaccine against tick based on protective antigen. Recombinant vaccines based on concealed antigen from Boophilus microplus have been developed in Australia and Cuba by the name of TICKGARD and GAVAC (De La Fuente and Kocan, 2006. Further studies on this antigen have shown some extent of protection against other species (De Vos et al., 2001. In Iran most important species is Hyalomma anatolicum and limited information about its control are available. This paper reports structural and polymorphic analysis of HA03 as an Iranian candidate concealed antigen of H. a. anatolicum deposited in Gen-Bank .(Aghaeipour et al. GQ228820. The comparison between this antigen and other mid gut concealed antigen that their characteristics are available in GenBank showed there are high rate of similarity between them. The HA03 amino acid sequence had a homology of around 89%, 64%, 56% with HA98, BM86, BM95 respectively. Potential of MHC class I and II binding region indicated a considerable variation between BM86 antigen and its efficiency against Iranian H. a. anatolicum. In addition, predicted major of hydrophobisity and similarity in N-glycosylation besides large amount of cystein and seven EGF like regions presented in protein structure revealed that value of HA03 as a new protective antigen and the necessity of the development, BM86 homolog of H. a. anatolicum HA03 based recombinant vaccine.

  5. Evaluation of collagen/heparin coated TCP/HA granules for long-term delivery of BMP-2.

    Science.gov (United States)

    Hannink, Gerjon; Geutjes, Paul J; Daamen, Willeke F; Buma, Pieter

    2013-02-01

    Bone morphogenetic proteins (BMPs) are the most potent osteoinductive growth factors. However, a delivery system is essential to take advantage of the osteoinductive effect of BMPs. The purpose of this study was to develop a sustained delivery system for recombinant human bone morphogenetic protein-2 (BMP-2). We covalently attached heparin to a cross-linked collagen type I coated tricalciumphosphate/hydroxyapatite (TCP/HA) bone substitute and subsequently loaded it with BMP-2. To systematically evaluate the contribution of each component with respect to the binding and release of BMP-2, six constructs were prepared and characterized: TCP/HA, TCP/HA with collagen (TCP/HACol), and TCP/HA with collagen and heparin (TCP/HAColHep) with and without BMP-2 (B). More BMP-2 bound to the TCP/HAColHep + B (92.9 ± 4.8 ng BMP-2/mg granule) granules as compared to the TCP/HACol + B (69.0 ± 9.6 ng BMP-2/mg granule) and TCP/HA + B granules (62.9 ± 5.4 ng BMP-2/mg granule). No difference in release pattern was found between the TCP/HA + B and TCP/HACol + B granules. Up to day 14, BMP-2 was still bound to the TCP/HAColHep + B granules, whereas most BMP had been released from TCP/HACol + B and TCP/HA + B granules at that time. After 21 days most BMP-2 also had been released from the TCP/HAColHep + B granules. The local and sustained delivery system for BMP-2 developed in this study may be useful as a carrier for BMP-2 and could possibly enhance bone regeneration efficacy for the treatment of large bone defects.

  6. Development of single-chain variable fragments (scFv) against influenza virus targeting hemagglutinin subunit 2 (HA2).

    Science.gov (United States)

    Li, Tai-Wei; Cheng, Shu-Fang; Tseng, Yen-Tzu; Yang, Yu-Chih; Liu, Wen-Chun; Wang, Sheng-Cyuan; Chou, Mei-Ju; Lin, Yu-Jen; Wang, Yueh; Hsiao, Pei-Wen; Wu, Suh-Chin; Chang, Ding-Kwo

    2016-01-01

    Influenza A viruses (IAV) are widespread in birds and domestic poultry, occasionally causing severe epidemics in humans and posing health threats. Hence, the need to develop a strategy for prophylaxis or therapy, such as a broadly neutralizing antibody against IAV, is urgent. In this study, single-chain variable fragment (scFv) phage display technology was used to select scFv fragments recognizing influenza envelope proteins. The Tomlinson I and J scFv phage display libraries were screened against the recombinant HA2 protein (rHA2) for three rounds. Only the third-round elution sample of the Tomlinson J library showed high binding affinity to rHA2, from which three clones (3JA18, 3JA62, and 3JA78) were chosen for preparative-scale production as soluble antibody by E. coli. The clone 3JA18 was selected for further tests due to its broad affinity for influenza H1N1, H3N2 and H5N1. Simulations of the scFv 3JA18-HA trimer complex revealed that the complementarity-determining region of the variable heavy chain (VH-CDR2) bound the stem region of HA. Neutralization assays using a peptide derived from VH-CDR2 also supported the simulation model. Both the selected antibody and its derived peptide were shown to suppress infection with H5N1 and H1N1 viruses, but not H3N2 viruses. The results also suggested that the scFvs selected from rHA2 could have neutralizing activity by interfering with the function of the HA stem region during virus entry into target cells.

  7. Hyaluronan (Erectus(R in der Behandlung der Osteoarthritis (OA des Kniegelenks - Ergebnisse einer offenen Anwendungsbeobachtung

    Directory of Open Access Journals (Sweden)

    Leeb BF

    2007-01-01

    Full Text Available Ziel der Untersuchung war es, praxisrelevante Daten hinsichtlich der Wirksamkeit, Verträglichkeit und Auswirkung auf die Lebensqualität einer in Österreich neu zugelassenen Hyaluronan-Präparation (Erectus(R; MW 1.100 KD zu erhalten. Patienten und Methodik: Zu diesem Zweck wurden 204 Patienten mit OA des Kniegelenkes, Kellgren-Lawrence (KL I–III (mean 61,1 a [31 a–100 a]; mean BMI 26,9; 57,2% weiblich, 42,8 % männlich von Oktober 2005 bis April 2006 in diese offene multizentrische Anwendungsbeobachtung eingeschlossen. Die Patienten erhielten fünf Injektionen Erectus(Rintraartikulär im Abstand von einer Woche. Primärer Endpunkt war die Verbesserung des Ruheschmerzes zu Visite 5 (Woche 5. Sekundäre Endpunkte waren Verbesserung des Ruheschmerzes bei Visite 6 (Woche 13 sowie des Bewegungsschmerzes, der Beweglichkeit und der Zufriedenheit mit der Lebenssituation. Alle Parameter wurden von den Patienten anhand einer Likert-Skala (0–10 beurteilt. Darüber hinaus erfolgte die Beurteilung von Gesamtwirksamkeit, Verträglichkeit und Gesamtzufriedenheit durch Prüfarzt und PatientIn. Die statistische Auswertung erfolgte mittels T-Test und Chi-Quadrat-Test. Fehlende Werte wurden gemäß LOCF ersetzt. Ergebnisse: Der Ruheschmerz wurde von den Patienten zu Beginn mit im Mittel 4,68 angegeben und verbesserte sich auf 2,04 bei Visite 5 bzw. auf 1,8 bei Visite 6 (p 0,01. Die Verbesserung war bei Patienten mit KL Grad I am stärksten und bei KL III am geringsten ausgeprägt. Die subjektive Beurteilung der Beweglichkeit sowie die Zufriedenheit, mit dem aktuellen Krankheitszustand längerfristig leben zu müssen, verbesserte sich ebenfalls signifikant (p 0,01, wobei dabei interessanterweise die stärksten Veränderungen bei Patienten mit KL III festzustellen waren. Patienten und Behandler beurteilten die globale Wirksamkeit parallel positiv, wie auch die Verträglichkeit. Die Beurteilung der Gesamtzufriedenheit nach einem Schulnotensystem (1–5 ergab

  8. El griot no ha muerto, viva el hip-hop

    Directory of Open Access Journals (Sweden)

    Fco. Javier González García-Mamely

    2015-11-01

    Full Text Available La oratura en África ha jugado un papel vital a lo largo de los milenios como un (único medio de preservar y transmitir la historia, la cultura y el imaginario de cada comunidad. El griot es un claro modelo de las artes orales, pero ha sufrido cambios drásticos en su modo de vida y en los recursos narrativos de los que dispone. Tras el mecenazgo de los grandes reyes y las sucesivas llegadas del islam, el colonialismo y los procesos de modernización y occidentalización, los griots se han tenido que adaptar a nuevos patrones, audiencias y medios de comunicación, convirtiéndose en políticos o en figuras del espectáculo. La aparición del rap y el hip-hop reclamando ser los “modernos griots” ha ocasionado una respuesta crítica y una atracción viral hacia el nuevo fenómeno, sea éste un nuevo género o una reinvención de la oratura del antiguo griot.

  9. Three-year clinical outcome after chondrocyte transplantation using a hyaluronan matrix for cartilage repair

    Energy Technology Data Exchange (ETDEWEB)

    Nehrer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.nehrer@meduniwien.ac.at; Domayer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Dorotka, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Schatz, K. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Bindreiter, U. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Kotz, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-01-15

    Repair of articular cartilage represents a significant clinical problem and although various new techniques - including the use of autologous chondrocytes - have been developed within the last century the clinical efficacy of these procedures is still discussed controversially. Although autologous chondrocyte transplantation (ACT) has been widely used with success, it has several inherent limitations, including its invasive nature and problems related to the use of the periosteal flap. To overcome these problems autologous chondrocytes transplantation combined with the use of biodegradable scaffolds has received wide attention. Among these, a hyaluronan-based scaffold has been found useful for inducing hyaline cartilage regeneration. In the present study, we have investigated the mid-term efficacy and safety of Hyalograft[reg] C grafts in a group of 36 patients undergoing surgery for chronic cartilage lesions of the knee. Clinical Outcome was assessed prospectively before and at 12, 24, and 36 months after surgery. No major adverse events have been reported during the 3-year follow-up. Significant improvements of the evaluated scores were observed (P < 0.02) at 1 year and a continued increase of clinical performance was evident at 2 and 3 years follow-up. Patients under 30 years of age with single lesions showed statistically significant improvements at all follow-up visits compared to those over 30 with multiple defects (P < 0.01). Hyalograft[reg] C compares favorably with classic ACT and is particularly indicated in younger patients with single lesions. The graft can be implanted through a miniarthrotomy and needs no additional fixation with sutures except optional fibrin gluing at the defect borders. These results suggest that Hyalograft[reg] C is a valid alternative to ACT.

  10. One intra-articular injection of hyaluronan prevents cell death and improves cell metabolism in a model of injured articular cartilage in the rabbit

    NARCIS (Netherlands)

    Jansen, Edwin J. P.; Ernans, Pieter J.; Douw, Conny M.; Guidemond, Nick A.; Van Rhijn, Lodewijk W.; Bulstra, Sjoerd K.; Kuijer, Roell

    2008-01-01

    The purpose of this study was to determine the effect of one intra-articular injection of hyaluronan on chondrocyte death and metabolism in injured cartilage. Twenty-three 6-month-old rabbits received partial-thickness articular cartilage defects created on each medial femoral condyle. In order to e

  11. Stereo-dynamics of the exchange reaction Ha+LiHb→LiHa+Hb and its isotopic variants

    Institute of Scientific and Technical Information of China (English)

    Zhai Hong-Sheng; Yin Shu-Hui

    2012-01-01

    The quasi-classical trajectory (QCT) method is used to calculate the stereo-dynamics of the exchange reaction Ha+LiHb→LiHa+Hb and its isotopic variants based on an accurate potential energy surface reported by Prudente et al.[Prudente F V,Marques J M C and Maniero A M 2009 Chem.Phys.Lett.474 18].The reactive probability of the title reaction is computed.The vector correlations and four polarization-dependent generalized differential cross sections (PDDCSs) at different collision energies are presented.The influences of the collision energy and the reagent rotation on the product polarization are studied in the present work.The results indicate that the product rotational angular momentum j' is not only aligned,but also oriented along the direction perpendicular to the scattering plane.The product polarization distributions of the title reaction and its isotopic variants exhibit distinct differences which may arise from different mass combinations.

  12. A case of cervical cancer expressed three mRNA variant of Hyaluronan-mediated motility receptor

    Science.gov (United States)

    Villegas-Ruíz, Vanessa; Salcedo, Mauricio; Zentella-Dehesa, Alejandro; de Oca, Edén V Montes; Román-Basaure, Edgar; Mantilla-Morales, Alejandra; Dávila-Borja, Víctor M; Juárez-Méndez, Sergio

    2014-01-01

    Cervical cancer is the second malignancy in Mexico, little is known about the prognostic factors associated with this disease. Several cellular components are important in their transformation and progression. Alternative mRNA splice is an important mechanism for generating protein diversity, nevertheless, in cancer unknown mRNA diversity is expressed. Hyaluronan-mediated motility receptor (HMMR, RHAMM, CD168) is a family member of proteins, hyaluronan acid dependent, and has been associated with different malignant processes such as: angiogenesis, cell invasiveness, proliferation, metastasis and poor outcome in some tumors. In the present study we identified expression of HMMR in cervical cancer by means of RT-PCR and sequencing. Our results indicate co-expression of two HMMR variants in all samples, and one case expressed three alternative HMMR splice transcripts. These results showed the heterogeneity of mRNA transcripts of HMMR that could express in cancer and the expression of HMMR could be marker of malignancy in CC. PMID:24966934

  13. Local delivery of hyaluronan as an adjunct to scaling and root planing in the treatment of chronic periodontitis.

    Science.gov (United States)

    Johannsen, Annsofi; Tellefsen, Monica; Wikesjö, Ulf; Johannsen, Gunnar

    2009-09-01

    The aim of the present study was to evaluate the adjunctive effect of the local application of a hyaluronan gel to scaling and root planing in the treatment of chronic periodontitis. Twelve patients with chronic periodontitis were recruited to participate in a study with a split-mouth design and provided informed consent. Plaque formation and bleeding on probing were evaluated pretreatment (baseline) and at 1, 4, and 12 weeks post-treatment. Probing depths and attachment levels were evaluated at baseline and at 12 weeks. The patients received full-mouth scaling and root planing. A hyaluronan gel was administered subgingivally in the test sites at baseline and after 1 week. Significant differences between test and control were evaluated using the paired t test, repeated-measures analysis of variance (Wilks lambda), and a non-parametric Wilcoxon signed-rank test. A significant reduction in bleeding on probing scores and probing depths was observed in both groups at 12 weeks (P scaling and root planing may have a beneficial effect on periodontal health in patients with chronic periodontitis.

  14. Influence of tiopronin, captopril and levamisole therapeutics on the oxidative degradation of hyaluronan.

    Science.gov (United States)

    Valachová, Katarína; Baňasová, Mária; Topoľská, Dominika; Sasinková, Vlasta; Juránek, Ivo; Collins, Maurice N; Šoltés, Ladislav

    2015-12-10

    The ability to protect hyaluronic acid (HA) from oxidative degradation by cupric ions and ascorbate (production of (•)OH and peroxy-type radicals) during acute phase joint inflammation has been investigated using the following drugs: tiopronin, captopril, and levamisole. Radical scavenging activity, i.e. the propensity for donation of electrons was assessed for the drugs by ABTS and DPPH assays. The kinetics of HA degradation have been measured in the presence of each drug using rotational viscometry. The results of ABTS and DPPH assays show the highest radical scavenging activity for captopril, followed by tiopronin. For levamisole, no effect was observed. Captopril and tiopronin prevented HA degradation induced by (•)OH radicals in a similar manner, while tiopronin was more effective in scavenging peroxy-type radicals. On the other hand, levamisole was shown to be a pro-oxidant. Recovered HA fragments were characterized using FT-IR analysis, the incorporation of a sulphur atom from captopril and tiopronin but not from levamisole into the HA molecule was demonstrated.

  15. TGF-α/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Mei Teh, Bing, E-mail: bing.teh@earscience.org.au [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Redmond, Sharon L. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Shen, Yi [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head and Neck, Ningbo Lihuili Hospital (Ningbo Medical Centre), Ningbo, Zhejiang (China); Atlas, Marcus D. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Marano, Robert J.; Dilley, Rodney J. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia)

    2013-04-01

    Tympanic membrane perforations are common and represent a management challenge to clinicians. Current treatments for chronic perforations involve a graft surgery and require general anaesthesia, including associated costs and morbidities. Bioactive molecules (e.g. growth factors, cytokines) play an important role in promoting TM wound healing following perforation and the use of growth factors as a topical treatment for tympanic membrane perforations has been suggested as an alternative to surgery. However, the choice of bioactive molecules best suited to promote wound healing has yet to be identified. We investigated the effects of hyaluronic acid, vitronectin, TGF-α, IL-24 and their combinations on migration, proliferation and adhesion of cultured human tympanic membrane-derived keratinocytes (hTM), in addition to their possible mechanisms of action. We found that TGF-α, TGF-α/HA and TGF-α/IL-24 promoted wound healing by significantly increasing both migration and proliferation. TGF-α and/or HA treated cells showed comparable cell–cell adhesion whilst maintaining an epithelial cell phenotype. With the use of receptor binding inhibitors for ErbB1 (AG1478) and CD44 (BRIC235), we revealed that the activation of ErbB1 is required for TGF-α/HA-mediated migration and proliferation. These results suggest factors that may be incorporated into a tissue-engineered membrane or directly as topical treatment for tympanic membrane perforations and hence reduce the need for a surgery. - Highlights: ► TGF-α, TGF-α/HA and TGF-α/IL-24 improved hTM keratinocyte migration and proliferation. ► TGF-α and/or HA maintained epithelial cell phenotype. ► TGF-α/HA-mediated migration and proliferation requires activation of ErbB1 receptor.

  16. Construction of Eukaryotic Expressing Plasmids Encoding HA and HA1 of Influenza A Virus and Their Transient Expression in HEK293 Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Weidong; LI Mingyuan; CAO Kang; YANG Jing; SHI Qiaofa; WANG Baoning; JIANG Zhonghua; LI Hong

    2006-01-01

    In order to explore the feasibility and protective efficiency of influenza DNA vaccine, we constructed eukaryotic expressing plasmids encoding HA and HA1 of influenza A virus (A/PR/8/34) and studied their expression in HEK293 cells. HA and HA1 genes were amplified by RT-PCR and cloned into pcDNA3. 1 (+) to generate pcDNA3. 1 (+)/HA and pcDNA3.1 (+)/HA1, respectively. After verification of the cloning fidelity by restriction endonuclease digestion, PCR, and sequencing, pcDNA3.1 (+)/HA and pcDNA3.1 (+)/HA1 were transfected into HEK293 cells using PolyFect Transfection Reagent. Immunofluorescence assay was used to detect the transient expressing cells. Fluorescence microscopy revealed strong expression of target gene in HEK293 cells transiently transfected with either pcDNA3. 1 (+)/HA or pcDNA3. 1 (+)/HA1. Therefore, the results confirm the successful construction of eukaryotic expressing plasmids capable of driving the eukaryotic expression of influenza virus antigen HA and HA1, which is likely to provide a basis for both further investigation of the mechanism of influenza viral infection and the development of influenza DNA vaccine.

  17. L'oggetto del desiderio ha il colore del vuoto

    Directory of Open Access Journals (Sweden)

    Giovanni Bottiroli

    2011-07-01

    Full Text Available L’oggetto del desiderio non è semplicemente un oggetto empirico; su ciò, con qualche esitazione, potrebbe esistere un consenso generale. Resta la difficoltà di indicare le caratteristiche dell’oggetto del desiderio: che non sono banalmente delle proprietà, e neanche solo delle parti (in senso empirico, come si potrebbe nominarle da un punto di vista mereologico. L’oggetto del desiderio ha uno statuto modale: è un oggetto modalmente diviso, nei registri e nei regimi. Nella dimensione del desiderio, tanto il soggetto quanto l’oggetto sono abitati dal conflitto tra il diviso e l’indiviso. La spinta verso l’indiviso corrisponde a ciò che Freud ha introdotto con la nozione enigmatica di «pulsione di morte». In termini lacaniani, è l’attrazione verso la Cosa (das Ding. E la Cosa vuole coincidere con se stessa, abolendo ogni distinzione. L’oggetto del desiderio non è un dato o una forma empirica, per attraente che sia: l’attrazione che esercita proviene dal caos. Alla pericolosa coincidenza del «vuoto-pieno» (das Ding il desiderio oppone il vuoto logico della non-coincidenza. Una teoria del desiderio non può fare a meno di una riflessione sui differenti significati del vuoto.

  18. Biomedical potential of chitosan/HA and chitosan/β-1,3-glucan/HA biomaterials as scaffolds for bone regeneration — A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Przekora, Agata, E-mail: agata.przekora@umlub.pl [Department of Biochemistry and Biotechnology, Medical University of Lublin, Chodzki 1, 20-093 Lublin (Poland); Palka, Krzysztof [Department of Materials Engineering, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin (Poland); Ginalska, Grazyna [Department of Biochemistry and Biotechnology, Medical University of Lublin, Chodzki 1, 20-093 Lublin (Poland)

    2016-01-01

    The aim of this work was to compare biomedical potential of chitosan/hydroxyapatite (chit/HA) and novel chitosan/β-1,3-glucan/hydroxyapatite (chit/glu/HA) materials as scaffolds for bone regeneration via characterization of their biocompatibility, porosity, mechanical properties, and water uptake behaviour. Biocompatibility of the scaffolds was assessed in direct-contact with the materials using normal human foetal osteoblast cell line. Cytotoxicity and osteoblast proliferation rate were evaluated. Porosity was assessed using computed microtomography analysis and mechanical properties were determined by compression testing. Obtained results demonstrated that chit/HA scaffold possessed significantly better mechanical properties (compressive strength: 1.23 MPa, Young's modulus: 0.46 MPa) than chit/glu/HA material (compressive strength: 0.26 MPa, Young's modulus: 0.25 MPa). However, addition of bacterial β-1,3-glucan to the chit/HA scaffold improved its flexibility and porosity. Moreover, chit/glu/HA scaffold revealed significantly higher water uptake capability (52.6% after 24 h of soaking) compared to the chit/HA (30.7%) and thus can serve as a very good drug delivery carrier. Chit/glu/HA scaffold was also more favourable to osteoblast survival (near 100% viability after 24-h culture), proliferation, and spreading compared to the chit/HA (63% viability). The chit/glu/HA possesses better biomedical potential than chit/HA scaffold. Nevertheless, poor mechanical properties of the chit/glu/HA limit its application to non-load bearing implantation area. - Highlights: • Chitosan/HA and chit/β-1,3-glucan/HA scaffolds for bone regeneration were compared. • Chit/HA significantly reduced osteoblast viability to 63% compared to chit/glu/HA. • Unlike chit/HA, chit/glu/HA favoured cell adhesion, spreading, and proliferation. • Chit/HA had better compressive strength and Young's modulus than chit/glu/HA. • Chit/glu/HA revealed significantly higher

  19. Bør leger ha reservasjonsrett ved assistert befruktning?

    Directory of Open Access Journals (Sweden)

    Morten Magelssen

    2011-10-01

    Full Text Available Omfanget av helsepersonells reservasjonsrett har nylig vært gjenstand for debatt i Norge. Vi spør om leger bør ha reservasjonsrett ved utførelse og henvisning til assistert befruktning, og drøfter argumenter for og imot ved hjelp av et rammeverk med sju kriterier for vurdering av reservasjon. Reservasjonsrettens grunnleggende dilemma er hvordan to viktige hensyn, henholdsvis pasientens rett til behandling og hensynet til helsepersonellets moralske integritet, best kan ivaretas. Det argumenteres for at leger bør ha rett til å reservere seg mot å utføre, assistere ved og henvise til assistert befruktning generelt hvis begrunnelsen er hensynet til befruktede eggs moralske verdi. Videre finner vi at leger også kan ha en moralsk rett til reservasjon mot å utføre, assistere ved og henvise til assistert befruktning for likekjønnede, men da på nærmere spesifiserte vilkår.Nøkkelord: reservasjonsrett, assistert befruktning, samvittighet, moralsk integritetEnglish summary: Should physicians have the right to conscientiously object to assisted reproduction?The extent of the healthcare worker's right to conscientious objection has recently been debated in Norway. This article asks whether physicians should have a right to conscientious objection to the performance of, and referral for, assisted reproduction, and discusses arguments for and against the same, utilizing a framework of seven criteria for the evaluation of conscientious objection. The fundamental dilemma of conscientious objection is how two important considerations can be reconciled: the patient's right to treatment, and the protection of the healthcare worker's moral integrity. It is argued that physicians should have the right to object to performing, assisting with, and referring for assisted reproduction generally when the objection is grounded in the moral value of the embryo. Furthermore, physicians may also have a moral right to object to performing, assisting with, and

  20. Immunomodulatory Effects of Hemagglutinin- (HA- Modified A20 B-Cell Lymphoma Expanded as a Brain Tumor on Adoptively Transferred HA-Specific CD4+ T Cells

    Directory of Open Access Journals (Sweden)

    Valentin P. Shichkin

    2014-01-01

    Full Text Available Previously, the mouse A20 B-cell lymphoma engineered to express hemagglutinin (HA antigen (A20HA was used as a systemic tumor model. In this work, we used the A20HA cells as a brain tumor. HA-specific CD4+ T cells were transferred intravenously in a tail vein 5 days after A20HA intracranial inoculation and analyzed on days 2, 9, and 16 after the adoptive transfer by different methods. The transferred cells demonstrated state of activation as early as day 2 after the adoptive transfer and most the of viable HA-specific cells became anergic on day 16. Additionally, symptoms of systemic immunosuppression were observed in mice with massive brain tumors at a late stage of the brain tumor progression (days 20–24 after the A20HA inoculation. Despite that, a deal of HA-specific CD4+ T cells kept the functional activity even at the late stage of A20HA tumor growth. The activated HA-specific CD4+ T cells were found also in the brain of brain-tumor-bearing mice. These cells were still responding to reactivation with HA-peptide in vitro. Our data support an idea about sufficient role of both the tumor-specific and -nonspecific mechanisms inducing immunosuppression in cancer patients.

  1. Glycosylation of Residue 141 of Subtype H7 Influenza A Hemagglutinin (HA) Affects HA-Pseudovirus Infectivity and Sensitivity to Site A Neutralizing Antibodies

    Science.gov (United States)

    Alvarado-Facundo, Esmeralda; Vassell, Russell; Schmeisser, Falko; Weir, Jerry P.; Weiss, Carol D.; Wang, Wei

    2016-01-01

    Human infections with H7 subtype influenza virus have been reported, including an H7N7 outbreak in Netherlands in 2003 and H7N9 infections in China in 2013. Previously, we reported murine monoclonal antibodies (mAbs) that recognize the antigenic site A of H7 hemagglutinin (HA). To better understand protective immunity of H7 vaccines and vaccine candidate selection, we used these mAbs to assess the antigenic relatedness among two H7 HA isolated from past human infections and determine residues that affect susceptibility to neutralization. We found that these mAbs neutralize pseudoviruses bearing HA of A/Shanghai/02/2013(H7N9), but not A/Netherlands/219/2003(H7N7). Glycosylation of the asparagine residue at position 141 (N141) (N133, H3 HA numbering) in the HA of A/Netherlands/219/2003 HA is responsible for this resistance, and it affects the infectivity of HA-pseudoviruses. The presence of threonine at position 143 (T135, H3 HA numbering) in the HA of A/Netherlands/219/2003, rather than an alanine found in the HA of A/Shanghai/02/2013(H7N9), accounts for these differences. These results demonstrate a key role for glycosylation of residue N141 in affecting H7 influenza HA-mediated entry and sensitivity to neutralizing antibodies, which have implications for candidate vaccine design. PMID:26862918

  2. Comparative analysis of hyaluronan gel and xanthan-based chlorhexidine gel, as adjunct to scaling and root planing with scaling and root planing alone in the treatment of chronic periodontitis: A preliminary study

    Directory of Open Access Journals (Sweden)

    Avinash Singh Chauhan

    2013-01-01

    Full Text Available Aim : The aim of this study was to evaluate the effects of hyaluronan (HA and chlorhexidine (CHX gels as adjunct to scaling and root planing (SRP in the treatment of chronic periodontitis. Materials and Methods: Sixty patients within the age group of 30-65 years recruited to participate in the study were randomly equally divided into three groups. Complete SRP and subgingival debridement were performed within 6 h in all the patients. For control (Group I patients, SRP was the only treatment modality given; for Group II and III patients, at least 8 teeth with 4-8 mm probing pocket depth (PPD were selected for subgingival application of HA gel and CHX gel, respectively. Clinical periodontal parameters such as gingival index, PPD, and clinical attachment level (CAL were recorded at baseline and 3 months, whereas plaque index was recorded at baseline, 1 month, and 3 months. For measuring systemic/hematological parameters, blood samples for laboratory tests for total leucocyte count (TLC, differential leucocyte count (DLC, and C-reactive protein (CRP were obtained using standard 2-mL syringe from each subject in all the three groups at baseline, 24 h, and on the 1 month and 3 months post-baseline. Results: In all the three groups, a significant reduction in PPD and gain in CAL were observed between baseline and 3 months follow-up ( P < 0.05; however, at 3 months, change in PPD and CAL was more in Group II than Group III, but the difference was non-significant, and Group I (control showed less changes in PPD and CAL than both experimental groups. Only one patient revealed positive value for CRP at baseline only, and hence could not be statistically analyzed. In all the three groups, the peak values for TLC count were observed at 24 h. At 1-month and 3-month intervals, a significant improvement in TLC and DLC counts was observed among the experimental (HA gel/SRP and Xan-CHX gel groups as compared to control group (SRP alone.

  3. Low temperature spark plasma sintering of TC4/HA composites

    Institute of Scientific and Technical Information of China (English)

    Huiliang Shao; Lei Cao; Daqian Sun; Zhankui Zhao

    2016-01-01

    Ti6Al4V/hydroxyapatite composites (TC4/HA) have been prepared by high energy ball milling and low temperature spark plasma sintering at 600 °C, 550 °C, 500 °C and 450 °C, respectively. The sintering temperature of the composites was sharply decreased as the result of the activation and surficial modification effects induced from high energy ball milling. The decomposition and reaction of hydro-xyapatite was successfully avoided, which offers the composites superior biocompatibility. The hydro-xyapatite in the composites was distributed in gap uniformly, and formed an ideal network structure. The lowest hardness, compressive strength and Young's modulus of the composites satisfy the requirements of human bone.

  4. Synergistic interaction of platelet derived growth factor (PDGF) with the surface of PLLA/Col/HA and PLLA/HA scaffolds produces rapid osteogenic differentiation.

    Science.gov (United States)

    Raghavendran, Hanumantha Rao Balaji; Mohan, Saktiswaren; Genasan, Krishnamurithy; Murali, Malliga Raman; Naveen, Sangeetha Vasudevaraj; Talebian, Sepehr; McKean, Robert; Kamarul, Tunku

    2016-03-01

    Scaffolds with structural features similar to the extracellular matrix stimulate rapid osteogenic differentiation in favorable microenvironment and with growth factor supplementation. In this study, the osteogenic potential of electrospun poly-l-lactide/hydroxyapatite/collagen (PLLA/Col/HA, PLLA/HA and PLLA/Col) scaffolds were tested in vitro with the supplementation of platelet derived growth factor-BB (PDGF-BB). Cell attachment and topography, mineralization, extracellular matrix protein localization, and gene expression of the human mesenchymal stromal cells were compared between the fibrous scaffolds PLLA/Col/HA, PLLA/Col, and PLLA/HA. The levels of osteocalcin, calcium, and mineralization were significantly greater in the PLLA/Col/HA and PLLA/HA compared with PLLA/Col. High expression of fibronectin, intracellular adhesion molecule, cadherin, and collagen 1 (Col1) suggests that PLLA/Col/HA and PLLA/HA scaffolds had superior osteoinductivity than PLLA/Col. Additionally, osteopontin, osteocalcin, osterix, Runt-related transcription factor 2 (Runx2), and bone morphogenic protein (BMP2) expression were higher in PLLA/Col/HA and PLLA/HA compared with PLLA/Col. In comparison with PLLA/Col, the PLLA/Col/HA and PLLA/HA scaffolds presented a significant upregulation of the genes Runx2, Col 1, Integrin, osteonectin (ON), bone gamma-carboxyglutamic acid-containing protein (BGALP), osteopontin (OPN), and BMP2. The upregulation of these genes was further increased with PDGF-BB supplementation. These results show that PDGF-BB acts synergistically with PLLA/Col/HA and PLLA/HA to enhance the osteogenic differentiation potential. Therefore, this combination can be used for the rapid expansion of bone marrow stromal cells into bone-forming cells for tissue engineering.

  5. Binding Procurement

    Science.gov (United States)

    Rao, Gopalakrishna M.; Vaidyanathan, Hari

    2007-01-01

    This viewgraph presentation reviews the use of the binding procurement process in purchasing Aerospace Flight Battery Systems. NASA Engineering and Safety Center (NESC) requested NASA Aerospace Flight Battery Systems Working Group to develop a set of guideline requirements document for Binding Procurement Contracts.

  6. Haïti : entre urgence et reconstruction

    Directory of Open Access Journals (Sweden)

    Jean-Marc Biquet

    2014-01-01

    Full Text Available Note de l’éditeur : Cette contribution vient alimenter la section « Policy Debate » de la Revue de politique internationale de développement. Des universitaires, décideurs et praticiens y dialoguent autour d’enjeux globaux du développement. Le processus de publication des « Policy Debate » est différent de celle des autres sections. Les contributions sont éditées et corrigées, mais pas expertisés par des pairs. Une contribution thématique initiale lance le débat. Elle est suivie de commentaires critiques et de réactions de diverses parties. Jean-Marc Biquet, chargé de recherche à Médecin sans Frontière (MSF, livre une contribution sur la faillite du système d’aide en Haïti. Ce pays a été particulièrement touché par deux catastrophes coup sur coup : le séisme en janvier 2010 et une épidémie de choléra en octobre de la même année. Malgré des demandes répétées (et engagements reçus aux Nations unies (en particulier, à l’UNOCHA, nous n’avons malheureusement pas reçu de réaction écrite à l’article de Jean-Marc Biquet provenant de ces institutions. Cependant, nous avons reçu un commentaire critique de Andrea Binder, Directrice associée du Global Public Policy Institute (GPPi de Berlin ‘Is the Humanitarian Failure in Haiti a System Failure?’, que nous publions conjointement au texte de Jean-Marc Biquet. Dr Biner a notamment été étroitement impliquée dans le processus  d’évaluation inter-agences en temps réel de l’intervention humanitaire en Haïti suite au tremblement de terre. Téléchargez l’intégralité du débat en format .pdf sur http://poldev.revues.org/pdf/1600

  7. Silk-hyaluronan-based composite hydrogels: a novel, securable vehicle for drug delivery.

    Science.gov (United States)

    Elia, Roberto; Newhide, Danny R; Pedevillano, Paul D; Reiss, G Russell; Firpo, Matthew A; Hsu, Edward W; Kaplan, David L; Prestwich, Glenn D; Peattie, Robert A

    2013-02-01

    A new, biocompatible hyaluronic acid (HA)-silk hydrogel composite was fabricated and tested for use as a securable drug delivery vehicle. The composite consisted of a hydrogel formed by cross-linking thiol-modified HA with poly(ethylene glycol)-diacrylate, within which was embedded a reinforcing mat composed of electrospun silk fibroin protein. Both HA and silk are biocompatible, selectively degradable biomaterials with independently controllable material properties. Mechanical characterization showed the composite tensile strength as fabricated to be 4.43 ± 2.87 kPa, two orders of magnitude above estimated tensions found around potential target organs. In the presence of hyaluronidase (HAse) in vitro, the rate of gel degradation increased with enzyme concentration although the reinforcing silk mesh was not digested. Composite gels demonstrated the ability to store and sustainably deliver therapeutic agents. Time constants for in vitro release of selected representative antibacterial and anti-inflammatory drugs varied from 46.7 min for cortisone to 418 min for hydrocortisone. This biocomposite showed promising mechanical characteristics for direct fastening to tissue and organs, as well as controllable degradation properties suitable for storage and release of therapeutically relevant drugs.

  8. La Ha de la infancia en Italia. Problemas y perspectiva

    Directory of Open Access Journals (Sweden)

    Enzo CATARSI

    2010-03-01

    Full Text Available RESUMEN: La historiografía italiana de la infancia, como la de otros muchos países europeos, está hoy embarcada en una tarea de desarrollo y profundización que permitirá recuperar los retrasos que la han caracterizado. En efecto, también en Italia la historia de la infancia y su individuación como «objeto» historiografía constituyen una adquisición reciente, lograda con la ayuda de diversas influencias. La primera, estrechamente vinculada a la historia de las mentalidades, representada por la obra de Ph. Aries, «El niño y la vida familiar en el Antiguo Régimen», traducido al italiano en 1968. La segunda es la historia social, orientada al estudio de los diversos aspectos de la vida de una sociedad, y más atenta a sus acontecimientos. La tercera la representa el estructuralismo, especialmente el francés, y en concreto M. Foucault. La particular influencia que, también en el contexto italiano, han alcanzado los trabajos de Ph. Aries y L. DeMause, muy importantes por haber abierto una línea de investigación, aunque con las obligadas diferencias, ha conducido a privilegiar una perspectiva exclusiva de historia de las mentalidades que se muestra muy ambigua y claramente interpretativa en exceso.

  9. A comparative study on in vitro osteogenic priming potential of electron spun scaffold PLLA/HA/Col, PLLA/HA, and PLLA/Col for tissue engineering application.

    Science.gov (United States)

    Balaji Raghavendran, Hanumantha Rao; Puvaneswary, Subramaniam; Talebian, Sepehr; Murali, Malliga R; Raman Murali, Malliga; Naveen, Sangeetha V; Vasudevaraj Naveen, Sangeetha; Krishnamurithy, G; McKean, Robert; Kamarul, Tunku

    2014-01-01

    A comparative study on the in vitro osteogenic potential of electrospun poly-L-lactide/hydroxyapatite/collagen (PLLA/HA/Col, PLLA/HA, and PLLA/Col) scaffolds was conducted. The morphology, chemical composition, and surface roughness of the fibrous scaffolds were examined. Furthermore, cell attachment, distribution, morphology, mineralization, extracellular matrix protein localization, and gene expression of human mesenchymal stromal cells (hMSCs) differentiated on the fibrous scaffolds PLLA/Col/HA, PLLA/Col, and PLLA/HA were also analyzed. The electrospun scaffolds with a diameter of 200-950 nm demonstrated well-formed interconnected fibrous network structure, which supported the growth of hMSCs. When compared with PLLA/H%A and PLLA/Col scaffolds, PLLA/Col/HA scaffolds presented a higher density of viable cells and significant upregulation of genes associated with osteogenic lineage, which were achieved without the use of specific medium or growth factors. These results were supported by the elevated levels of calcium, osteocalcin, and mineralization (PCol/HA scaffolds exhibited superior osteoinductivity, when compared with PLLA/Col or PLLA/HA scaffolds. These findings indicated that the fibrous structure and synergistic action of Col and nano-HA with high-molecular-weight PLLA played a vital role in inducing osteogenic differentiation of hMSCs. The data obtained in this study demonstrated that the developed fibrous PLLA/Col/HA biocomposite scaffold may be supportive for stem cell based therapies for bone repair, when compared with the other two scaffolds.

  10. Topical stabilized retinol treatment induces the expression of HAS genes and HA production in human skin in vitro and in vivo.

    Science.gov (United States)

    Li, Wen-Hwa; Wong, Heng-Kuan; Serrano, José; Randhawa, Manpreet; Kaur, Simarna; Southall, Michael D; Parsa, Ramine

    2017-05-01

    Skin Aging manifests primarily with wrinkles, dyspigmentations, texture changes, and loss of elasticity. During the skin aging process, there is a loss of moisture and elasticity in skin resulting in loss of firmness finally leading to skin sagging. The key molecule involved in skin moisture is hyaluronic acid (HA), which has a significant water-binding capacity. HA levels in skin decline with age resulting in decrease in skin moisture, which may contribute to loss of firmness. Clinical trials have shown that topically applied ROL effectively reduces wrinkles and helps retain youthful appearance. In the current study, ROL was shown to induce HA production and stimulates the gene expression of all three forms of hyaluronic acid synthases (HAS) in normal human epidermal keratinocytes monolayer cultures. Moreover, in human skin equivalent tissues and in human skin explants, topical treatment of tissues with a stabilized-ROL formulation significantly induced the gene expression of HAS mRNA concomitant with an increased HA production. Finally, in a vehicle-controlled human clinical study, histochemical analysis confirmed increased HA accumulation in the epidermis in ROL-treated human skin as compared to vehicle. These results show that ROL increases skin expression of HA, a significant contributing factor responsible for wrinkle formation and skin moisture, which decrease during aging. Taken together with the activity to increase collagen, elastin, and cell proliferation, these studies establish that retinol provides multi-functional activity for photodamaged skin.

  11. Amino Acid Substitutions Improve the Immunogenicity of H7N7HA Protein and Protect Mice against Lethal H7N7 Viral Challenge.

    Directory of Open Access Journals (Sweden)

    Subaschandrabose Rajesh Kumar

    Full Text Available Avian influenza A H7N7/NL/219/03 virus creates a serious pandemic threat to human health because it can transmit directly from domestic poultry to humans and from human to human. Our previous vaccine study reported that mice when immunized intranasally (i.n with live Bac-HA were protected from lethal H7N7/NL/219/03 challenge, whereas incomplete protection was obtained when administered subcutaneously (s.c due to the fact that H7N7 is a poor inducer of neutralizing antibodies. Interestingly, our recent vaccine studies reported that mice when vaccinated subcutaneously with Bac-HA (H7N9 was protected against both H7N9 (A/Sh2/2013 and H7N7 virus challenge. HA1 region of both H7N7 and H7N9 viruses are differ at 15 amino acid positions. Among those, we selected three amino acid positions (T143, T198 and I211 in HA1 region of H7N7. These amino acids are located within or near the receptor binding site. Following the selection, we substituted the amino acid at these three positions with amino acids found on H7N9HA wild-type. In this study, we evaluate the impact of amino acid substitutions in the H7N7 HA-protein on the immunogenicity. We generated six mutant constructs from wild-type influenza H7N7HA cDNA by site directed mutagenesis, and individually expressed mutant HA protein on the surface of baculovirus (Bac-HAm and compared their protective efficacy of the vaccines with Bac-H7N7HA wild-type (Bac-HA by lethal H7N7 viral challenge in a mouse model. We found that mice immunized subcutaneously with Bac-HAm constructs T143A or T198A-I211V or I211V-T143A serum showed significantly higher hemagglutination inhibition and neutralization titer against H7N7 and H7N9 viruses when compared to Bac-HA vaccinated mice groups. We also observed low level of lung viral titer, negligible weight loss and complete protection against lethal H7N7 viral challenge. Our results indicated that amino acid substitution at position 143 or 211 improve immunogenicity of H7N7HA

  12. Preparation and properties of HA coating hydrothermally synthesized from plasma sprayed CaHPO4 coating

    Institute of Scientific and Technical Information of China (English)

    FU Tao; HAN Yong; ZHANG Yu-mei; XU Ke-wei

    2001-01-01

    @@ INTRODUCTION Hydroxyapatite (HA) biocoatings can form osseointegration at a shorter time than metallic implants, and plasma sprayed (PS) HA coating has received the widest studies and is now used clinically. However, due to the high temperature of plasma flame, soluble impurity phases and amorphous calcium phosphate were contained which declined the bonding strength of the coating, and spoiled the excellent biological properties of HA.

  13. Degradation behavior and compatibility of micro, nanoHA/chitosan scaffolds with interconnected spherical macropores.

    Science.gov (United States)

    Ruixin, Li; Cheng, Xu; Yingjie, Liu; Hao, Li; Caihong, Shi; Weihua, Su; Weining, An; Yinghai, Yuan; Xiaoli, Qin; Yunqiang, Xu; Xizheng, Zhang; Hui, Li

    2017-03-30

    Hydroxyapatite/Chitosan (HA/CS) composite have significant application in biomedical especially for bone replacement. Inorganic particle shape and size of composite affect the scaffold mechanical property, biological property, and degradation. The aim of this study was to fabricate HA/CS scaffold with good pore connectivity and analyze their biological, degradation properties. Microhydroxyapatite/chitosan(mHA/CS) and nanohydroxyapatite/chitosan (nHA/CS) composite scaffolds with interconnected spherical pore architectures were fabricated. Composite scaffolds structure parameters were analyzed using micro CT. Cell proliferation and morphology were tested and compared between two scaffolds using mouse osteoblastic cell line MC3T3-E1. To research the composite degradation in lysozyme PBS solution, degradation rate and reducing sugar content were tested, and scaffolds morphology were observed by SEM. The results showed that microHA and nanoHA were fabricated by being calcined and synthesis methods, and their infrared spectra are very similar. EDAX composition analysis demonstrated that both of microHA and nanoHA were calcium deficiency HA. Micro-CT results demonstrated the scaffolds had interconnected spherical pores, and the structure parameters were similar. Cell viabilities were significant increased with cultured time, but there were no significant difference between microHA/CS and nanoHA/CS scaffolds. Scaffold structure was gradually destroyed and inorganic composition HA particles are more prominent with degradation time.

  14. Complexation and sequestration of BMP-2 from an ECM mimetic hyaluronan gel for improved bone formation.

    Directory of Open Access Journals (Sweden)

    Marta Kisiel

    Full Text Available Bone morphogenetic protein-2 (BMP-2 is considered a promising adjuvant for the treatment of skeletal non-union and spinal fusion. However, BMP-2 delivery in a conventional collagen scaffold necessitates a high dose to achieve an efficacious outcome. To lower its effective dose, we precomplexed BMP-2 with the glycosaminoglycans (GAGs dermatan sulfate (DS or heparin (HP, prior to loading it into a hyaluronic acid (HA hydrogel. In vitro release studies showed that BMP-2 precomplexed with DS or HP had a prolonged delivery compared to without GAG. BMP-2-DS complexes achieved a slightly faster release in the first 24 h than HP; however, both delivered BMP-2 for an equal duration. Analysis of the kinetic interaction between BMP-2 and DS or HP showed that HP had approximately 10 times higher affinity for BMP-2 than DS, yet it equally stabilized the protein, as determined by alkaline phosphatase activity. Ectopic bone formation assays at subcutaneous sites in rats demonstrated that HA hydrogel-delivered BMP-2 precomplexed with GAG induced twice the volume of bone compared with BMP-2 delivered uncomplexed to GAG.

  15. The interaction of versican with its binding partners

    Institute of Scientific and Technical Information of China (English)

    Yao Jiong WU; David P.LA PIERRE; Jin WU; Albert J.YEE; Burton B.YANG

    2005-01-01

    Versican belongs to the family of the large aggregating chondroitin sulfate proteoglycans located primarily within the extracellular matrix (ECM).Versican,like other members of its family,has unique N- and C-terminal globular regions,each with multiple motifs.A large glycosaminoglycan-binding region lies between them.This review will begin by outlining these structures,in the context of ECM proteoglycans.The diverse binding partners afforded to versican by virtue of its modular design will then be examined.These include ECM components,such as hyaluronan,type Ⅰ collagen,tenascin-R,fibulin-1,and -2,fibrillin-1,fibronectin,P- and L-selectins,and chemokines.Versican also binds to the cell surface proteins CD44,integrin β1,epidermal growth factor receptor,and P-selectin glycoprotein ligand-1.These multiple interactors play important roles in cell behaviour,and the roles of versican in modulating such processes are discussed.

  16. Intravitreal administration of HA-1077, a ROCK inhibitor, improves retinal function in a mouse model of huntington disease.

    Directory of Open Access Journals (Sweden)

    Mei Li

    Full Text Available Huntington disease (HD is an inherited neurodegenerative disease that affects multiple brain regions. It is caused by an expanded polyglutamine tract in huntingtin (Htt. The development of therapies for HD and other neurodegenerative diseases has been hampered by multiple factors, including the lack of clear therapeutic targets, and the cost and complexity of testing lead compounds in vivo. The R6/2 HD mouse model is widely used for pre-clinical trials because of its progressive and robust neural dysfunction, which includes retinal degeneration. Profilin-1 is a Htt binding protein that inhibits Htt aggregation. Its binding to Htt is regulated by the rho-associated kinase (ROCK, which phosphorylates profilin at Ser-137. ROCK is thus a therapeutic target in HD. The ROCK inhibitor Y-27632 reduces Htt toxicity in fly and mouse models. Here we characterized the progressive retinopathy of R6/2 mice between 6-19 weeks of age to determine an optimal treatment window. We then tested a clinically approved ROCK inhibitor, HA-1077, administered intravitreally via liposome-mediated drug delivery. HA-1077 increased photopic and flicker ERG response amplitudes in R6/2 mice, but not in wild-type littermate controls. By targeting ROCK with a new inhibitor, and testing its effects in a novel in vivo model, these results validate the in vivo efficacy of a therapeutic candidate, and establish the feasibility of using the retina as a readout for CNS function in models of neurodegenerative disease.

  17. Self-healing hybrid nanocomposites consisting of bisphosphonated hyaluronan and calcium phosphate nanoparticles

    NARCIS (Netherlands)

    Nejadnik, M.R.; Yang, X.; Bongio, M.; Alghamdi, H.S.A.; Beucken, J.J.J.P van den; Huysmans, M.C.D.N.J.M.; Jansen, J.A.; Hilborn, J.; Ossipov, D.; Leeuwenburgh, S.C.G.

    2014-01-01

    Non-covalent interactions are often regarded as insufficient to construct macroscopic materials of substantial integrity and cohesion. However, the low binding energy of such reversible interactions can be compensated by increasing their number to work in concert to create strong materials. Here we

  18. Hypochlorite and superoxide radicals can act synergistically to induce fragmentation of hyaluronan and chondroitin sulphates

    DEFF Research Database (Denmark)

    Rees, Martin D; Hawkins, Clare Louise; Davies, Michael Jonathan

    2004-01-01

    chelators and the metal ion-binding protein BSA, consistent with chloramide decomposition and polymer fragmentation occurring via O2*--dependent one-electron reduction, possibly catalysed by trace metal ions. Polymer fragmentation induced by O2*- [generated by the superoxide thermal source 1, di-(4...

  19. Fibronectin-integrin mediated signaling in human cervical cancer cells (SiHa).

    Science.gov (United States)

    Maity, Gargi; Fahreen, Shabana; Banerji, Aniruddha; Roy Choudhury, Paromita; Sen, Triparna; Dutta, Anindita; Chatterjee, Amitava

    2010-03-01

    Interaction between cell surface integrin receptors and extracellular matrix (ECM) components plays an important role in cell survival, proliferation, and migration, including tumor development and invasion of tumor cells. Matrix metalloproteinases (MMPs) are a family of metalloproteinases capable of digesting ECM components and are important molecules for cell migration. Binding of ECM to integrins initiates cascades of cell signaling events modulating expression and activity of different MMPs. The aim of this study is to investigate fibronectin-integrin-mediated signaling and modulation of MMPs. Our findings indicated that culture of human cervical cancer cell (SiHa) on fibronectin-coated surface perhaps sends signals via fibronectin-integrin-mediated signaling pathways recruiting focal adhesion kinase (FAK) extracellular signal regulated kinase (ERK), phosphatidyl inositol 3 kinase (PI-3K), integrin-linked kinase (ILK), nuclear factor-kappa B (NF-kappaB), and modulates expression and activation of mainly pro-MMP-9, and moderately pro-MMP-2 in serum-free culture medium.

  20. The novel kinetics expression of Cadmium (II) removal using green adsorbent horse dung humic acid (Hd-Ha)

    Science.gov (United States)

    Basuki, Rahmat; Santosa, Sri Juari; Rusdiarso, Bambang

    2017-03-01

    Humic acid from dry horse dung powder has been prepared and this horse dung humic acid (HD-HA) was then applied as a sorbent to adsorb Cadmium(II) from a solution. Characterization of HD-HA was conducted by detection of its functional group, UV-Vis spectra, ash level, and total acidity. Result of the work showed that HD-HA had similar character compared with peat soil humic acid (PS-HA) and previous researchers. The adsorption study of this work was investigated by batch experiment in pH 5. The thermodynamics parameters in this work were determined by the Langmuir isotherm model for monolayer sorption and Freundlich isotherm model multilayer sorption. Monolayer sorption capacity (b) for HD-HA was 1.329 × 10-3 mol g-1, equilibrium constant (K) was 5.651 (mol/L)-1, and multilayer sorption capacity was 2.646 × 10-2 mol g-1. The kinetics parameters investigated in this work were determined by the novel kinetics expression resulted from the mathematical derivation the availability of binding sites of sorbent. Adsorption rate constant (ka) from this novel expression was 43.178 min-1 (mol/L)-1 and desorption rate constant (kd) was 1.250 × 10-2 min-1. Application of the kinetics model on sorption Cd(II) onto HD-HA showed the nearly all of models gave a good linearity. However, only this proposed kinetics expression has good relation with Langmuir model. The novel kinetics expression proposed in this paper seems to be more realistic and reasonable and close to the experimental real condition because the value of ka/kd (3452 (mol/L)-1) was fairly close with K from Langmuir isotherm model (5651 (mol/L)-1). Comparison of this novel kinetics expression with well-known Lagergren pseudo-first order kinetics and Ho pseudo-second order kinetics was also critically discussed in this paper.

  1. A critical HA1 neutralizing domain of H5N1 influenza in an optimal conformation induces strong cross-protection.

    Directory of Open Access Journals (Sweden)

    Lanying Du

    Full Text Available The highly pathogenic avian influenza (HPAI H5N1 viruses, especially the laboratory-generated H5N1 mutants, have demonstrated the potential to cross the species barrier and infect mammals and humans. Consequently, the design of an effective and safe anti-H5N1 vaccine is essential. We previously demonstrated that the full-length hemagglutinin 1 (HA1 could induce significant neutralizing antibody response and protection. Here, we intended to identify the critical neutralizing domain (CND in an optimal conformation that can elicit strong cross-neutralizing antibodies and protection against divergent H5N1 strains. We thus constructed six recombinant proteins covering different regions of HA1 of A/Anhui/1/2005(H5N1, each of which was fused with foldon (Fd and Fc of human IgG. We found that the critical fragment fused with Fd/Fc (HA-13-263-Fdc, H5 numbering that could elicit the strongest neutralizing antibody response is located in the N-terminal region of HA1 (residues 13-263, which covers the receptor-binding domain (RBD, residues 112-263. We then constructed three additional recombinants fused with Fd plus His tag (HA-13-263-Fd-His, Fc only (HA-13-263-Fc, and His tag only (HA-13-263-His, respectively. We found that the HA-13-263-Fdc, which formed an oligomeric conformation, induced the strongest neutralizing antibody response and cross-protection against challenges of two tested H5N1 virus strains covering clade 1: A/VietNam/1194/2004 (VN/1194 or clade 2.3.4: A/Shenzhen/406H/06 (SZ/406H, while HA-13-263-Fc dimer and HA-13-263-Fd-His trimer elicited higher neutralizing antibody response and protection than HA-13-263-His monomer. These results suggest that the oligomeric form of the CND containing the RBD can be further developed as an effective and safe vaccine for cross-protection against divergent strains of H5N1 viruses.

  2. A comparative study on in vitro osteogenic priming potential of electron spun scaffold PLLA/HA/Col, PLLA/HA, and PLLA/Col for tissue engineering application.

    Directory of Open Access Journals (Sweden)

    Hanumantha Rao Balaji Raghavendran

    Full Text Available A comparative study on the in vitro osteogenic potential of electrospun poly-L-lactide/hydroxyapatite/collagen (PLLA/HA/Col, PLLA/HA, and PLLA/Col scaffolds was conducted. The morphology, chemical composition, and surface roughness of the fibrous scaffolds were examined. Furthermore, cell attachment, distribution, morphology, mineralization, extracellular matrix protein localization, and gene expression of human mesenchymal stromal cells (hMSCs differentiated on the fibrous scaffolds PLLA/Col/HA, PLLA/Col, and PLLA/HA were also analyzed. The electrospun scaffolds with a diameter of 200-950 nm demonstrated well-formed interconnected fibrous network structure, which supported the growth of hMSCs. When compared with PLLA/H%A and PLLA/Col scaffolds, PLLA/Col/HA scaffolds presented a higher density of viable cells and significant upregulation of genes associated with osteogenic lineage, which were achieved without the use of specific medium or growth factors. These results were supported by the elevated levels of calcium, osteocalcin, and mineralization (P<0.05 observed at different time points (0, 7, 14, and 21 days. Furthermore, electron microscopic observations and fibronectin localization revealed that PLLA/Col/HA scaffolds exhibited superior osteoinductivity, when compared with PLLA/Col or PLLA/HA scaffolds. These findings indicated that the fibrous structure and synergistic action of Col and nano-HA with high-molecular-weight PLLA played a vital role in inducing osteogenic differentiation of hMSCs. The data obtained in this study demonstrated that the developed fibrous PLLA/Col/HA biocomposite scaffold may be supportive for stem cell based therapies for bone repair, when compared with the other two scaffolds.

  3. Architectural organization and functional features of early endothelial progenitor cells cultured in a hyaluronan-based polymer scaffold.

    Science.gov (United States)

    Pasquinelli, Gianandrea; Vinci, Maria Cristina; Gamberini, Chiara; Orrico, Catia; Foroni, Laura; Guarnieri, Carlo; Parenti, Astrid; Gargiulo, Mauro; Ledda, Fabrizio; Caldarera, Claudio Marcello; Muscari, Claudio

    2009-09-01

    Neovascularization can be improved using polymer scaffolds supporting endothelial progenitor cells (EPCs). The aim of the present study was to investigate whether human early EPCs (eEPCs) could be efficiently cultured in a hyaluronan-based non-woven mesh (HYAFF-11). eEPCs were seeded on HYAFF-11 at the density of 1 x 10(6)/cm(2) and cultured with endothelial differentiating factors for 3 weeks. After 24 h, nearly 90% of EPCs were adherent. Cell viability, evaluated by methyltetrazolium test, was greater in HYAFF-11 than on the most commonly used fibronectin-coated dishes, even if a progressive decline in viability was observed starting from approximately the second week of culture. eEPCs easily migrated to and aggregated on the scaffold. Evidence of active protein synthesis and features of endothelial differentiation, including cellular transcytotic channels and micropinocytotic vesicles, was revealed using electron microscopy, immunofluorescence, and reverse transcriptase polymerase chain reaction analysis. eEPCs cultured in the scaffold also showed a certain angiogenic activity, as demonstrated by hepatocyte growth factor transcription and vascular endothelial growth factor secretion. In conclusion, eEPCs can migrate and adhere inside HYAFF-11, maintain their pre-endothelial phenotype, and express angiogenic factors, especially within the first week of growth. These results indicate that non-woven HYAFF-11 could be a promising candidate as a vehicle for eEPCs for regenerative medicine applications.

  4. Low- and high-resolution nuclear magnetic resonance (NMR) characterisation of hyaluronan-based native and sulfated hydrogels.

    Science.gov (United States)

    Barbucci, Rolando; Leone, Gemma; Chiumiento, Antonio; Di Cocco, Maria Enrica; D'Orazio, Giovanni; Gianferri, Raffaella; Delfini, Maurizio

    2006-08-14

    Hyaluronan-based hydrogels were synthesised using different crosslinking agents, such as 1,3-diaminopropane (1,3-DAP) and 1,6-diaminohexane (1,6-DAE). The hydrogels were sulfated to provide materials (Hyal-1,3-DAP, Hyal-1,6-DAE, HyalS-1,3-DAP and HyalS-1,6-DAE) that were characterised by both high- and low-resolution nuclear magnetic resonance (NMR) spectroscopy. The (13)C NMR spectra of the materials were analysed to identify, characterise and study the crosslinking degree of the hydrogels. The crosslinking degree was also determined by potentiometric titration and the effectiveness of the two techniques was compared. Measurements of longitudinal relaxation times (spin-lattice) and of NOE enhancement were used to study the mobility of the hydrogels. Low-resolution NMR studies allowed the determination of the water transport properties in the hydrogels. In addition, the swelling degree for the various hydrogels was calculated as a function of the longitudinal and transversal relaxation times of the water molecules. Lastly, the self-diffusion coefficients of the water in interaction with the four polysaccharides were measured by the pulsed field gradient spin echo (PFGSE) sequence.

  5. Preliminary Study on c-Ha-ras Oncogene Mutations in Hydatidiform Mole Tissues

    Institute of Scientific and Technical Information of China (English)

    王芳; 谭运年; 陈碧; 李英勇; 康旭

    2001-01-01

    Objective To study the presence of c-Ha-fas oncogene mutations in hydatidiform mole (HM) tissues and to further explore its relationship with mole's malignancy Materials & methods c-Ha-ras codon 12 mutation was detected in invasive and noninvasive HM by using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).Results c-Ha-fas codon 12 mutation was detected in 7 samples (53. 85%) of 13 invasive HM and 8 samples (26. 67%) in 30 non-invasive HM. c-Ha-ras mutations also showed loss of wild-type c-Ha-fas. No mutation in control group was observed.Conclusion The tendency of c-Ha-ras codon 12 mutation may be related with a higher invasive degree of HM.

  6. The Technology and Properties of Digital Double Pulse Electrodepositing Ni-HA Composite Coating of Bioceramics

    Institute of Scientific and Technical Information of China (English)

    DONG He-yan; WANG Zhou; SHI Gu-guizhi; FU Chuan-qi; CHEN Wei-rong; JIN Zhong-hong; LI Yan

    2004-01-01

    This article discusses and analyses the technology, the surface image, microstructure and ability of digital double pulse electrodepositing Ni-HA composite coatings of bioceramics made on 1Crl8Ni9Ti substrate by SEM ,XRD and so on. The results shows that ( 1 ) the HA particles exit in substrate uniformly; (2) XRD result shows that there are HA peaks at 78. 023 ° ,43. 246°and 73. 120°differently; (3) The microhardnees of the composite coatings is increased with the rise of content of HA particles, and on the same conditions the microhardnees value is greater than that of common non-pulse electrodepositing Ni-HA composite coatings of bioceramics. (4) The grain size of digital double pulse electrodepositing Ni-HA composite coatings of bioceramics is much thinner than that of common D. C.

  7. Preparation and characterization of bio-composite PEEK/nHA

    Science.gov (United States)

    Jin, Y. S.; Bian, C. C.; Zhang, Z. Q.; Zhao, Y.; Yang, L.

    2017-01-01

    PEEK/nHA composite material, with excellent mechanical property as polyetheretherketone (PEEK) and biological activity as hydroxyapatite (HA), has attracted wide attention of medical experts and materials science experts. The addition of hydroxyapatite was the decisive factor for biological activity in PEEK/nHA composite. In this paper, acicular nanohydroxyapatite was prepared by chemical precipitation method with Ca(NO3)2, (NH4)2HPO4 as raw material; PEEK/nHA composite was prepared by solution blending and vacuum sintering method. The composite was characterized with FT-IR, XRD, DSC, TG and mechanical property test. Results showed that the composite has good thermal stability and compressive property when the mass ratio of PEEK to nHA is 10:3; and high nHA content can improve the biological activity of the composite, which can meet the basic requirements for bone tissue engineering scaffold.

  8. HDPE-HA composites synthetized by in situ polymerization with different filler content

    Science.gov (United States)

    Hermán, V.; Karam, A.; Albano, C.; Romero, K.; González, G.

    2012-07-01

    In Situ ethylene polymerization was used to synthesize high density polyethylene - hydroxyapatite (HDPE-HA) composites, employing Cp2ZrCl2/MAO as catalytic system. A good dispersion of HA into the HDPE matrix was obtained when the following synthesis conditions were combined: high stirring velocities (2000 rpm), low quantities of solvent (100 mL), and 10 °C. Under these conditions different filler content was used to synthetized HDPE-HA composites. An interaction between HA and HDPE was obtained by FTIR. On the other hand, thermal analysis indicated that no significant differences were observed between HDPE and the composites.

  9. Enhanced Mechanical Properties and Corrosion Behavior of Biodegradable Mg-Zn/HA Composite

    Science.gov (United States)

    Salleh, Emee Marina; Zuhailawati, Hussain; Ramakrishnan, Sivakumar; Dhindaw, Brij Kumar

    2017-03-01

    Magnesium (Mg) and its alloys have shown potential for use in the biomedical industry due to their excellent biological performance and biodegradability in the bioenvironment. Thus, the aim of the present study was to develop a reliable biodegradable hard tissue substituent. Biodegradable and bioactive Mg-Zinc (Zn) reinforced by hydroxyapatite (HA) composite was prepared using mechanically alloyed Mg-6.5 wt pct Zn and pure HA powders as starting materials. Various HA contents (i.e., 5, 10, 15, and 20 wt pct) were introduced in forming the Mg-Zn/HA composite. The effect of bioactive HA incorporation in biodegradable Mg-6.5 wt pct Zn alloy matrix on mechanical and biodegradation properties as well as microstructural observation was investigated. As measured by the Williamson-Hall formula, the Mg crystallite size of the sintered composites containing 5, 10, 15, and 20 wt pct HA were 36.76, 29.08, 27.93, and 27.31 nm, respectively. According to X-ray diffraction (XRD) analysis, there was no new crystalline phase formed during milling, indicating that no mechanochemical reactions between Mg-Zn alloy and HA occurred. The -1.70 V shifted significantly toward the passive position of the plain Mg-6.5 wt pct Zn alloy and Mg-Zn/10 wt pct HA composite, which were -1.50 and -1.46 V, respectively, indicating that the Mg-Zn/10 wt pct HA composite was least susceptible to corrosion in the bioenvironment.

  10. A study on improving mechanical properties of porous HA tissue engineering scaffolds by hot isostatic pressing

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Jing [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Xiao Suguang [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Lu Xiong [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Wang Jianxin [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Weng Jie [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

    2006-12-15

    Various interconnected porous hydroxyapatite (HA) ceramic scaffolds are universally used to induct the tissue growth for bone repair and replacement, and serve to support the adhesion, transfer, proliferation and differentiation of cells. Impregnation of polyurethane sponges with a ceramic slurry is adopted to produce highly porous HA ceramic scaffolds with a 3D interconnected structure. However, high porosity always accompanies a decrease in the strength of the HA ceramic scaffolds. Therefore, it is significant to improve the strength of the HA ceramic scaffolds with highly interconnected porosity so that they are more suitable in clinical applications. In this work, highly porous HA ceramic scaffolds are first produced by the polymer impregnation approach, and subsequently further sintered by hot isostatic pressing (HIP). The phase composition, macro- and micro-porous structure, sintering and mechanical properties of the porous HA scaffolds are investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), nanoindentation analysis and compressive test. The experimental results show that the nanohardness and compressive strength of HIP-sintered porous HA ceramics are higher than those of commonly sintered HA scaffolds. The HIP technique can effectively improve the sintering property and densification of porous HA ceramic scaffolds, so inducing an increase in the compression strength.

  11. Synthesis and Characterization of PVA-HA-Silk Composite Hydrogel by Orthogonal Experiment

    Institute of Scientific and Technical Information of China (English)

    Dekun Zhang; Kai Chen; Lin Wu; Dagang Wang; Shirong Ge

    2012-01-01

    PVA-HA-Silk composite hydrogel was synthesized with polyvinyl alcohol (PVA),nano-hydroxyapatite (HA) and natural silk by using the method of repeated freezing and thawing.A series of tests were performed to study water content,stress relaxation behavior,elastic modulus,and creep characteristics of PVA-HA-Silk composite hydrogel.Orthogonal experimental design method was used to analyze the influence degree of PVA,HA and silk (three kinds of raw materials) on mechanical properties and water content of the PVA-HA-Silk composite hydrogel to select the best material ratio according to their overall performance.The results demonstrate that the mass percentage of PVA has the greatest impact on the water content,followed by HA and silk.Compression stress-strain variation of PVA-HA-Silk composite hydrogel presents a nonlinear relationship,which proves that it is a typical viscoelastic material.Comparing the mechanical properties of 16 formulas,the formula of PVA-HA-silk composite hydrogel with mass percentage of PVA 15%,HA 2.0% and silk 1.0% is the best.

  12. Enhanced Mechanical Properties and Corrosion Behavior of Biodegradable Mg-Zn/HA Composite

    Science.gov (United States)

    Salleh, Emee Marina; Zuhailawati, Hussain; Ramakrishnan, Sivakumar; Dhindaw, Brij Kumar

    2017-05-01

    Magnesium (Mg) and its alloys have shown potential for use in the biomedical industry due to their excellent biological performance and biodegradability in the bioenvironment. Thus, the aim of the present study was to develop a reliable biodegradable hard tissue substituent. Biodegradable and bioactive Mg-Zinc (Zn) reinforced by hydroxyapatite (HA) composite was prepared using mechanically alloyed Mg-6.5 wt pct Zn and pure HA powders as starting materials. Various HA contents ( i.e., 5, 10, 15, and 20 wt pct) were introduced in forming the Mg-Zn/HA composite. The effect of bioactive HA incorporation in biodegradable Mg-6.5 wt pct Zn alloy matrix on mechanical and biodegradation properties as well as microstructural observation was investigated. As measured by the Williamson-Hall formula, the Mg crystallite size of the sintered composites containing 5, 10, 15, and 20 wt pct HA were 36.76, 29.08, 27.93, and 27.31 nm, respectively. According to X-ray diffraction (XRD) analysis, there was no new crystalline phase formed during milling, indicating that no mechanochemical reactions between Mg-Zn alloy and HA occurred. The -1.70 V shifted significantly toward the passive position of the plain Mg-6.5 wt pct Zn alloy and Mg-Zn/10 wt pct HA composite, which were -1.50 and -1.46 V, respectively, indicating that the Mg-Zn/10 wt pct HA composite was least susceptible to corrosion in the bioenvironment.

  13. Eco-friendly microwave-assisted protocol to prepare hyaluronan-fatty acid conjugates and to induce their self-assembly process.

    Science.gov (United States)

    Calce, Enrica; Mercurio, Flavia Anna; Leone, Marilisa; Saviano, Michele; De Luca, Stefania

    2016-06-05

    An environmentally sustainable and energy-efficient synthetic process has been developed to prepare hyaluronan-based nano-sized material. It consists in a microwave-promoted acylation of the hydroxyl function of the polysaccharide with natural fatty acids, performed under solvent-free conditions. The efficient interaction of the solid reagents with the MW radiation accounts for the obtained high yielded products. The self-assembly process of the obtained compounds very fast occurred in an aqueous medium under MW-radiation, thus allowing the development of a green protocol for the nano-particles preparation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Study on the genotoxicity of HA/ZrO{sub 2} composite particles in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Quan, Renfu, E-mail: quanrenfu8@yahoo.com [Xiaoshan Traditional Chinese Medical Hospital, ZhengJiang Province 311200 (China); Tang, Yanghua; Huang, Zhongming; Xu, Jinwei [Xiaoshan Traditional Chinese Medical Hospital, ZhengJiang Province 311200 (China); Wu, Xiaochen [School of Materials Science and Engineering, Shanghai University, Shanghai (China); Yang, Disheng [Department of Orthopedics, the second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou 310009 (China)

    2013-04-01

    To evaluate the genotoxicity of the HA/ZrO{sub 2} composite particles by using the micronucleus test (MNT) in vitro. HA/ZrO{sub 2} composite particles prepared by sintering at high temperature and pressure, that used powder of HA and ZrO{sub 2} of different proportions, were compared with pure HA particles and pure ZrO{sub 2} particles. The effect of the composite particles on cell proliferation of rabbit mesenchymal stem cells, and its the genotoxicity to rabbit mesenchymal stem cells were detected by MNT method. The MTT test showed that both pure HA particles and composite particles which contained HA promoted cell proliferation of rabbit mesenchymal stem cells, while pure ZrO{sub 2} particles did not, and there was a significant difference (P < 0.05). The MNT test showed no significant difference between the HA group and the negative control group (P > 0.05), but a significant difference between the HA group and the positive control group (P < 0.05). The difference between the ZrO{sub 2} group and the negative control group was significant (P < 0.01), while the difference between the ZrO{sub 2} group and the positive control group was insignificant (P > 0.05). The genotoxicity of the HA/ZrO{sub 2} composite particle increased with a higher proportion of ZrO{sub 2} and an increase in the concentration of the composite, and the 30 wt.% HA/70% ZrO{sub 2} composite with 200 μg/mL concentration showed significant genotoxicity (P < 0.01). - Highlights: ► HA/ZrO{sub 2} composite particles were prepared by sintering used powder of HA and ZrO{sub 2} of different proportions. ► Evaluate the genotoxicity of the HA/ZrO{sub 2} composite particle in vitro micronucleus test (MNT). ► The genotoxicity of the HA/ZrO{sub 2} composite particle increased with an increase in the proportion of ZrO{sub 2}. ► The 30%wtHA/70% ZrO{sub 2} composite with 200 μg/mL concentration showed significant genotoxicity.

  15. Serum amyloid P component binds to influenza A virus haemagglutinin and inhibits the virus infection in vitro

    DEFF Research Database (Denmark)

    Andersen, Ove; Vilsgaard Ravn, K; Juul Sørensen, I;

    1997-01-01

    that SAP can bind to influenza A virus and inhibit agglutination of erythrocytes mediated by the virus subtypes H1N1, H2N2 and H3N2. SAP also inhibits the production of haemagglutinin (HA) an the cytopathogenic effect of influenza A virus in MDCK cells. The binding of SAP to the virus requires...... to the mass of the HA1 peptide. Of several monosaccharides tested only D-mannose interfered with SAP's inhibition of both HA and infectivity. The glycosaminoglycans heparan sulfate and heparin, which bind SAP, reduced SAPs binding to the virus. The results indicate that the inhibition by SAP is due to steric...

  16. Serum amyloid P component binds to influenza A virus haemagglutinin and inhibits the virus infection in vitro

    DEFF Research Database (Denmark)

    Andersen, Ove; Vilsgaard Ravn, K; Juul Sørensen, I

    1997-01-01

    that SAP can bind to influenza A virus and inhibit agglutination of erythrocytes mediated by the virus subtypes H1N1, H2N2 and H3N2. SAP also inhibits the production of haemagglutinin (HA) an the cytopathogenic effect of influenza A virus in MDCK cells. The binding of SAP to the virus requires...... to the mass of the HA1 peptide. Of several monosaccharides tested only D-mannose interfered with SAP's inhibition of both HA and infectivity. The glycosaminoglycans heparan sulfate and heparin, which bind SAP, reduced SAPs binding to the virus. The results indicate that the inhibition by SAP is due to steric...

  17. Self-healing hybrid nanocomposites consisting of bisphosphonated hyaluronan and calcium phosphate nanoparticles.

    Science.gov (United States)

    Nejadnik, M Reza; Yang, Xia; Bongio, Matilde; Alghamdi, Hamdan S; van den Beucken, Jeroen J J P; Huysmans, Marie C; Jansen, John A; Hilborn, Jöns; Ossipov, Dmitri; Leeuwenburgh, Sander C G

    2014-08-01

    Non-covalent interactions are often regarded as insufficient to construct macroscopic materials of substantial integrity and cohesion. However, the low binding energy of such reversible interactions can be compensated by increasing their number to work in concert to create strong materials. Here we present the successful development of an injectable, cohesive nanocomposite hydrogel based on reversible bonds between calcium phosphate nanoparticles and bisphosphonate-functionalized hyaluronic acid. These nanocomposites display a capacity for self-healing as well as adhesiveness to mineral surfaces such as enamel and hydroxyapatite. Most importantly, these non-covalently cross-linked composites are surprisingly robust yet biodegradable upon extensive in vitro and in vivo testing and show bone interactive capacity evidenced by bone ingrowth into material remnants. The herein presented method provides a new methodology for constructing nanoscale composites for biomedical applications, which owe their integrity to reversible bonds.

  18. New insight to structure-function relationship of GalNAc mediated primary interaction between insecticidal Cry1Ac toxin and HaALP receptor of Helicoverpa armigera.

    Science.gov (United States)

    Sengupta, Anindita; Sarkar, Anindya; Priya, Prerna; Ghosh Dastidar, Shubhra; Das, Sampa

    2013-01-01

    Over the last few decades Cry1Ac toxin has been widely used in controlling the insect attack due to its high specificity towards target insects. The pore-forming toxin undergoes a complex mechanism in the insect midgut involving sequential interaction with specific glycosylated receptors in which terminal GalNAc molecule plays a vital role. Recent studies on Cry toxins interactions with specific receptors revealed the importance of several amino acid residues in domain III of Cry1Ac, namely Q509, N510, R511, Y513 and W545, serve as potential binding sites that surround the putative GalNAc binding pocket and mediate the toxin-receptor interaction. In the present study, alanine substitution mutations were generated in the Cry1Ac domain III region and functional significance of those key residues was monitored by insect bioassay on Helicoverpa armigera larvae. In addition, ligand blot analysis and SPR binding assay was performed to monitor the binding characteristics of Cry1Ac wild type and mutant toxins towards HaALP receptor isolated from Helicoverpa armigera. Mutagenesis data revealed that, alanine substitutions in R511, Y513 and W545 substantially impacted the relative affinity towards HaALP receptor and toxicity toward target insect. Furthermore, in silico study of GalNAc-mediated interaction also confirmed the important roles of these residues. This structural analysis will provide a detail insight for evaluating and engineering new generation Cry toxins to address the problem of change in insect behavioral patterns.

  19. Inherited polymorphisms in hyaluronan synthase 1 predict risk of systemic B-cell malignancies but not of breast cancer.

    Directory of Open Access Journals (Sweden)

    Hemalatha Kuppusamy

    Full Text Available Genetic variations in the hyaluronan synthase 1 gene (HAS1 influence HAS1 aberrant splicing. HAS1 is aberrantly spliced in malignant cells from multiple myeloma (MM and Waldenstrom macroglobulinemia (WM, but not in their counterparts from healthy donors. The presence of aberrant HAS1 splice variants predicts for poor survival in multiple myeloma (MM. We evaluated the influence of inherited HAS1 single nucleotide polymorphisms (SNP on the risk of having a systemic B cell malignancy in 1414 individuals compromising 832 patients and 582 healthy controls, including familial analysis of an Icelandic kindred. We sequenced HAS1 gene segments from 181 patients with MM, 98 with monoclonal gammopathy of undetermined significance (MGUS, 72 with Waldenstrom macroglobulinemia (WM, 169 with chronic lymphocytic leukemia (CLL, as well as 34 members of a monoclonal gammopathy-prone Icelandic family, 212 age-matched healthy donors and a case-control cohort of 295 breast cancer patients with 353 healthy controls. Three linked single nucleotide polymorphisms (SNP in HAS1 intron3 are significantly associated with B-cell malignancies (range p = 0.007 to p = 10(-5, but not MGUS or breast cancer, and predict risk in a 34 member Icelandic family (p = 0.005, Odds Ratio = 5.8 (OR, a relatively homogeneous cohort. In contrast, exon3 SNPs were not significantly different among the study groups. Pooled analyses showed a strong association between the linked HAS1 intron3 SNPs and B-cell malignancies (OR = 1.78, but not for sporadic MGUS or for breast cancer (OR<1.0. The minor allele genotypes of HAS1 SNPs are significantly more frequent in MM, WM, CLL and in affected members of a monoclonal gammopathy-prone family than they are in breast cancer, sporadic MGUS or healthy donors. These inherited changes may increase the risk for systemic B-cell malignancies but not for solid tumors.

  20. Renal intratubular crystals and hyaluronan staining occur in stone formers with bypass surgery but not with idiopathic calcium oxalate stones.

    Science.gov (United States)

    Evan, Andrew P; Coe, Fredric L; Gillen, Daniel; Lingeman, James E; Bledsoe, Sharon; Worcester, Elaine M

    2008-03-01

    Whether idiopathic calcium oxalate (CaOx) stone formers form inner medullary collecting duct (IMCD) crystal deposits bears on pathogenetic mechanisms of stone formation. In prior work, using light and transmission electron microscopy, we have found no IMCD crystal deposits. Here, we searched serial sections of papillary biopsies from a prior study of 15 idiopathic calcium oxalate stone formers, 4 intestinal bypass patients with CaOx stones, and 4 non-stone-forming subjects, and biopsies from an additional hitherto unreported 15 idiopathic calcium oxalate stone formers and 1 bypass patient using polarized light oil immersion optics, for deposits overlooked in our original study. We found no IMCD deposits in any of 1,500 serial sections from the 30 idiopathic calcium oxalate stone formers, nor in 87 additional sections from a frozen idiopathic calcium oxalate stone former biopsy sample processed without exposure to aqueous solutions. Among 4 of the 5 bypass patients but in none of the 30 idiopathic calcium oxalate stone formers or 4 normal stone formers, we found tiny birefringent thin crystalline overlays on scattered IMCD cell membranes. We also found IMCD lumen deposits in two bypass patients that contained mixed birefringent and nonbirefringent crystals, presumably CaOx and apatite. In the bypass patients, we observed focal apical IMCD cell hyaluronan staining, which was absent in idiopathic calcium oxalate stone formers. The absence of any IMCD deposits in 1,500 serial sections of biopsies from 30 idiopathic calcium oxalate stone formers allows us to place the upper limit on the probability of their occurrence at approximately 0.002 and place the lower limit of their size at the resolution of the optics (crystal lesion.

  1. Cuando la "puesta en el juego" es un hijo que aún no ha nacido.

    Directory of Open Access Journals (Sweden)

    Giuliana Prata

    1990-01-01

    Full Text Available Los juegos de la pareja pueden influir en sus "puestas" un hijo que no ha nacido o que ni siquiera ha sido concebido. Síntomas tales como esterilidad, abortos espontáneos o muertes del niño durante el parto son examinados en este artículo a la luz de esta hipótesis.

  2. A novel PHBV/HA microsphere releasing system loaded with alendronate

    Energy Technology Data Exchange (ETDEWEB)

    Huang Wei [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Special Functional Materials, South China University of Technology, Ministry of Education, Guangzhou 510641 (China); Wang Yingjun, E-mail: imwangyj@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Special Functional Materials, South China University of Technology, Ministry of Education, Guangzhou 510641 (China); Ren Li; Du Chang; Shi Xuetao [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Special Functional Materials, South China University of Technology, Ministry of Education, Guangzhou 510641 (China)

    2009-08-31

    Microspheres of poly({beta}-hydroxybutyrate-co-{beta}-hydroxyvalerate) (PHBV) incorporated with hydroxyapatite (HA) and loaded with alendronate (AL), an osteoporosis preventing drugs, were prepared by single emulsion technique. Several methods were used to evaluate this novel drug carrier microsphere system (referred as PHBV/HA-AL). Fourier transform infrared (FTIR) was used to evaluate the enwrapping of HA and the X-ray diffraction (XRD) analysis further confirmed the success. The morphology of PHBV/HA-AL microspheres was observed by scanning electron microscope (SEM), showing rough surface with HA particles enwrapped in the PHBV matrix. The in vitro drug releasing profile of PHBV/HA-AL system was investigated in a 26-day period. There is a sustained releasing pattern after a slight burst release during the first few days. Additionally, rabbit mesenchymal stem cells (MSCs) were used to evaluate the cytotoxicity of the PHBV/HA-AL composites. This controlled release system can well support the proliferation of MSCs. The novel PHBV/HA-AL controlled release system is promising for bone repair therapy.

  3. Removal of Uranium in Drinking Water: Brimac Environmental Services, Inc. Brimac HA 216 Adsorptive Media

    Science.gov (United States)

    The Brimac HA 216 Adsorptive Media was tested for uranium (U) removal from a drinking water source (well water) at Grappone Toyota located in Bow, New Hampshire. The HA 216 media is a hydroxyapatite-based material. A pilot unit, consisting of a TIGG Corporation Cansorb® C-5 ste...

  4. Effect of bioactive extruded PLA/HA composite films on focal adhesion formation of preosteoblastic cells.

    Science.gov (United States)

    Persson, Maria; Lorite, Gabriela S; Kokkonen, Hanna E; Cho, Sung-Woo; Lehenkari, Petri P; Skrifvars, Mikael; Tuukkanen, Juha

    2014-09-01

    The quality of the initial cell attachment to a biomaterial will influence any further cell function, including spreading, proliferation, differentiation and viability. Cell attachment is influenced by the material's ability to adsorb proteins, which is related to the surface chemistry and topography of the material. In this study, we incorporated hydroxyapatite (HA) particles into a poly(lactic acid) (PLA) composite and evaluated the surface structure and the effects of HA density on the initial cell attachment in vitro of murine calvarial preosteoblasts (MC3T3-EI). Scanning electron microscopy (SEM), atomic force microscopy (AFM) and infrared spectroscopy (FTIR) showed that the HA particles were successfully incorporated into the PLA matrix and located at the surface which is of importance in order to maintain the bioactive effect of the HA particles. SEM and AFM investigation revealed that the HA density (particles/area) as well as surface roughness increased with HA loading concentration (i.e. 5, 10, 15 and 20wt%), which promoted protein adsorption. Furthermore, the presence of HA on the surface enhanced cell spreading, increased the formation of actin stress fibers and significantly improved the expression of vinculin in MC3T3-E1 cells which is a key player in the regulation of cell adhesion. These results suggest the potential utility of PLA/HA composites as biomaterials for use as a bone substitute material and in tissue engineering applications.

  5. Printsess ja pühak : Püha Elisabeth Tallinna altaritel / Kaie Hiiesalu

    Index Scriptorium Estoniae

    Hiiesalu, Kaie

    2006-01-01

    Artikkel keskendub naispühakule Tüüringi Pühale Elisabethile (1207-1231). Vaatluse all on Püha Elisabethi kujutised - nikerdatud ja maalitud üksikfiguurid ning maalitud stseenid. Pikemalt peatutakse Püha Vaimu kiriku peaaltaril, kus Elisabethi on kujutatud altari kõigis kolmes asendis

  6. Registration of an oilseed sunflower germplasm HA-DM1 resistant to sunflower downy mildew

    Science.gov (United States)

    HA-DM1 (Reg. No.xxx, PI 674793) sunflower (Helianthus annuus L.) germplasm was developed and released cooperatively by the USDA-ARS, Sunflower and Plant Biology Research Unit and the North Dakota Agricultural Experiment Station in 2015. HA-DM1 is a BC2F4 derived oilseed maintainer line from the cros...

  7. Laser Annealing for Gas-Dynamical Spraying of HA Coating upon a Titanium Surface

    Directory of Open Access Journals (Sweden)

    Victor Saphronov

    2015-10-01

    Full Text Available Laser post-heating computer controlled detonation spraying (CCDS and cold spray (CS hybrid processes were proposed for fabrication of near sub micron structure coatings of hydroxyapatite (HA + Ti system. Optical and SEM with energy dispersive X-ray analysis and comparative XRD phase analysis were used to evaluate microstructure. After those hybrid processes, no substantial variation in HA composition was noted by structural and phase examination. Nano-sized HA powders can be recommended for laser annealing CS (LaCS process. Regimes of laser treatment optimal for increasing the adhesion between the HA and titanium coatings, providing more strength, ductility and decreasing of HA destruction in the coatings were determined.

  8. ANALYSIS OF C-HA-RAS GENE AMPLIFICATION AND MUTATION IN LARYNGEAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    刘世喜; 林代诚; 洪邦泰; 黄光琦

    1995-01-01

    In order to study the ahered molecular events during laryngeal carcinogenesis and elucidate the role of Ha-ras oncogene amplification and mutation, we have examined their profile by polymerase chain reaction (PCR) and selective oligonucleoride hybridization. We analyzed the mutational status of codon 12 of Ha-ras in 22 laryngeal carcinomas and 10 normal tissues, and found that 7 of 22 laryngeal carcinomas con-tained a Ha-ras mutation at codon 12. The frequency of mutation was 32%. None of the normal tissues re-vealed mutation. Moreover, no amplification was found in cancers when compared to the normal. Our findings indicated that the aefivmed Ha-ras gene existed in laryngeal carcinoma, and activation of the Ha-ras gene by mutation at codon 12 might play a key role in laryngeal carcinogenesis.

  9. Hydroxyapatite-binding peptides for bone growth and inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Bertozzi, Carolyn R. (Berkeley, CA); Song, Jie (Shrewsbury, MA); Lee, Seung-Wuk (Walnut Creek, CA)

    2011-09-20

    Hydroxyapatite (HA)-binding peptides are selected using combinatorial phage library display. Pseudo-repetitive consensus amino acid sequences possessing periodic hydroxyl side chains in every two or three amino acid sequences are obtained. These sequences resemble the (Gly-Pro-Hyp).sub.x repeat of human type I collagen, a major component of extracellular matrices of natural bone. A consistent presence of basic amino acid residues is also observed. The peptides are synthesized by the solid-phase synthetic method and then used for template-driven HA-mineralization. Microscopy reveal that the peptides template the growth of polycrystalline HA crystals .about.40 nm in size.

  10. Structures and receptor binding of hemagglutinins from human-infecting H7N9 influenza viruses.

    Science.gov (United States)

    Shi, Yi; Zhang, Wei; Wang, Fei; Qi, Jianxun; Wu, Ying; Song, Hao; Gao, Feng; Bi, Yuhai; Zhang, Yanfang; Fan, Zheng; Qin, Chengfeng; Sun, Honglei; Liu, Jinhua; Haywood, Joel; Liu, Wenjun; Gong, Weimin; Wang, Dayan; Shu, Yuelong; Wang, Yu; Yan, Jinghua; Gao, George F

    2013-10-11

    An avian-origin human-infecting influenza (H7N9) virus was recently identified in China. We have evaluated the viral hemagglutinin (HA) receptor-binding properties of two human H7N9 isolates, A/Shanghai/1/2013 (SH-H7N9) (containing the avian-signature residue Gln(226)) and A/Anhui/1/2013 (AH-H7N9) (containing the mammalian-signature residue Leu(226)). We found that SH-H7N9 HA preferentially binds the avian receptor analog, whereas AH-H7N9 HA binds both avian and human receptor analogs. Furthermore, an AH-H7N9 mutant HA (Leu(226) → Gln) was found to exhibit dual receptor-binding property, indicating that other amino acid substitutions contribute to the receptor-binding switch. The structures of SH-H7N9 HA, AH-H7N9 HA, and its mutant in complex with either avian or human receptor analogs show how AH-H7N9 can bind human receptors while still retaining the avian receptor-binding property.

  11. Prokaryotic Expression and Antigenic Analysis of H3N2 Swine Influenza Virus HA1 and HA2 Genes%H3N2亚型猪流感病毒HA1、HA2基因的原核表达及抗原性分析

    Institute of Scientific and Technical Information of China (English)

    宋玉慧; 王翔宇; 王洁琼; 潘梦梦; 张剑; 刘琳; 李新生

    2016-01-01

    血凝素(hemagglutinin,HA)蛋白是猪流感病毒(swine influenza virus,SIV)的一个重要蛋白,在疾病预防和治疗中具有重要作用。本试验旨在克隆和表达 H3N2亚型猪流感病毒 A/swine/Henan/1/2010(H3N2)的 HA1和 HA2基因。用含有 H3N2亚型 SIV 的鸡胚尿囊液提取 RNA,RT-PCR 扩增后将目的基因定向克隆到 pET-28a (+)原核表达载体上,并将其转入宿主菌 BL21(DE3)pLyS 进行表达,IPTG 诱导后经 SDS-PAGE 检测并用该病毒重组 HA 蛋白制备的特异性单克隆抗体1C10作为一抗对两种蛋白进行 Western blotting 分析。SDS-PAGE 结果显示,得到 HA1和 HA2大小分别为34.8、23.2 ku 的重组蛋白,Western blotting 结果表明,HA1蛋白与1C10单克隆抗体具有良好的反应原性,且1C10单克隆抗体表位在 HA1蛋白上。本试验结果为进一步研究血凝素蛋白的结构和功能,以及建立快速诊断方法和基因工程疫苗提供材料。%Hemagglutinin protein plays an important role in disease prevention and treatment of the swine influenza virus (SIV).In order to clone and express subtype H3N2 SIV A/swine/Henan/1/2010 (H3N2)HA1 and HA2 genes with chicken embryo allantoic fluid containing the H3N2 SIV after extraction of RNA.The HA1 gene and HA2 gene were amplified from the total RNA using RT-PCR and they were inserted into prokaryotic expression vector pET-28a (+)to construct recombinant expression vector.Then the vector was transformed and expressed in E .coli BL21 (DE3)pLyS.Then the bacteria were induced by IPTG and their lysates were ana-lyzed by SDS-PAGE and Western blotting,respectively.The monoclonal antibody 1C10,which was specific to HA protein,was used as primary antibody in Western blotting analysis.It was found that the expressed recombinant HA1 protein was 34.8 ku and recombinant HA2 protein was 23.2 ku analyzed by SDS-PAGE.As demonstrated by Western blotting,this HA1 expressed products showed the capacity of reacting with monoclonal antibody 1C10

  12. The human and mouse receptors of hyaluronan-mediated motility, RHAMM, genes (HMMR) map to human chromosome 5q33.2-qter and mouse chromosome 11

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, A.P.; McDonald, J.A. [Mayo Clinic Scottsdale, AZ (United States); Roller, M.L.; Camper, S.A. [Univ. of Michigan Medical School, Ann Arbor, MI (United States)] [and others

    1995-11-01

    The gene for the receptor for hyaluronan-mediated motility, RHAAM (designated hyaluronan-mediated motility receptor, HMMR (human) and Hmmr (mouse), for mapping purposes), was localized to human chromosome 5q33.2-qter by somatic cell and radiation hybrid analyses. Investigation of two interspecific back-crosses localized the mouse RHAMM (Hmmr) locus 18 cM from the centromere of mouse chromosome 11 within a region of synteny homology with human chromosome 5q23-q35 genes. The map position of the human RHAMM gene places it in a region comparatively rich in disease-associated genes, including those for low-frequency hearing loss, dominant limb-girdle muscular dystrophy, diastrophic dysplasia, Treacher Collins syndrome, and myeloid disorders associated with the 5q-syndrome. The RHAMM gene location and its ability to transform cells when overexpressed implicate RHAMM as a possible candidate gene in the pathogenesis of the recently described t(5;14)(q33-q34;q11) acute lymphoblastic leukemias. 18 refs., 1 fig.

  13. Correlation study between sperm concentration, hyaluronic acid-binding capacity and sperm aneuploidy in Hungarian patients.

    Science.gov (United States)

    Mokánszki, Attila; Molnár, Zsuzsanna; Ujfalusi, Anikó; Balogh, Erzsébet; Bazsáné, Zsuzsa Kassai; Varga, Attila; Jakab, Attila; Oláh, Éva

    2012-12-01

    Infertile men with low sperm concentration and/or less motile spermatozoa have an increased risk of producing aneuploid spermatozoa. Selecting spermatozoa by hyaluronic acid (HA) binding may reduce genetic risks such as chromosomal rearrangements and numerical aberrations. Fluorescence in-situ hybridization (FISH) has been used to evaluate the presence of aneuploidies. This study examined spermatozoa of 10 oligozoospermic, 9 asthenozoospermic, 9 oligoasthenozoospermic and 17 normozoospermic men by HA binding and FISH. Mean percentage of HA-bound spermatozoa in the normozoospermic group was 81%, which was significantly higher than in the oligozoospermic (Psex chromosomes (P=0.014) and chromosome 17 (P=0.0019), diploidy (P=0.03) and estimated numerical chromosome aberrations (P=0.004) were significantly higher in the oligoasthenozoospermic group compared with the other groups. There were statistically significant relationships (Pchromosome aberrations (r=-0.668) and between HA binding and estimated numerical chromosome aberrations (r=-0.682). HA binding and aneuploidy studies of spermatozoa in individual cases allow prediction of reproductive prognosis and provision of appropriate genetic counselling. Infertile men with normal karyotypes and low sperm concentrations and/or less motile spermatozoa have significantly increased risks of producing aneuploid (diminished mature) spermatozoa. Selecting spermatozoa by hyaluronic acid (HA) binding, based on a binding between sperm receptors for zona pellucida and HA, may reduce the potential genetic risks such as chromosomal rearrangements and numerical aberrations. In the present study we examined sperm samples of 45 men with different sperm parameters by HA-binding assay and fluorescence in-situ hybridization (FISH). Mean percentage of HA-bound spermatozoa in the normozoospermic group was significantly higher than the oligozoospermic, the asthenozoospermic and the oligoasthenozoospermic groups. Using FISH, disomy of sex

  14. Incoming human papillomavirus 16 genome is lost in PML protein-deficient HaCaT keratinocytes.

    Science.gov (United States)

    Bienkowska-Haba, Malgorzata; Luszczek, Wioleta; Keiffer, Timothy R; Guion, Lucile G M; DiGiuseppe, Stephen; Scott, Rona S; Sapp, Martin

    2017-05-01

    Human papillomaviruses (HPVs) target promyelocytic leukemia (PML) nuclear bodies (NBs) during infectious entry and PML protein is important for efficient transcription of incoming viral genome. However, the transcriptional down regulation was shown to be promoter-independent in that heterologous promoters delivered by papillomavirus particles were also affected. To further investigate the role of PML protein in HPV entry, we used small hairpin RNA to knockdown PML protein in HaCaT keratinocytes. Confirming previous findings, PML knockdown in HaCaT cells reduced HPV16 transcript levels significantly following infectious entry without impairing binding and trafficking. However, when we quantified steady-state levels of pseudogenomes in interphase cells, we found strongly reduced genome levels compared with parental HaCaT cells. Because nuclear delivery was comparable in both cell lines, we conclude that viral pseudogenome must be removed after successful nuclear delivery. Transcriptome analysis by gene array revealed that PML knockdown in clonal HaCaT cells was associated with a constitutive interferon response. Abrogation of JAK1/2 signaling prevented genome loss, however, did not restore viral transcription. In contrast, knockdown of PML protein in HeLa cells did not affect HPV genome delivery and transcription. HeLa cells are transformed by HPV18 oncogenes E6 and E7, which have been shown to interfere with the JAK/Stat signaling pathway. Our data imply that PML NBs protect incoming HPV genomes. Furthermore, they provide evidence that PML NBs are key regulators of the innate immune response in keratinocytes. Promyelocytic leukemia nuclear bodies (PML NBs) are important for antiviral defense. Many DNA viruses target these subnuclear structures and reorganize them. Reorganization of PML NBs by viral proteins is important for establishment of infection. In contrast, HPVs require the presence of PML protein for efficient transcription of incoming viral genome. Our

  15. Dihydrotestosterone induces SREBP-1 expression and lipogenesis through the phosphoinositide 3-kinase/Akt pathway in HaCaT cells

    Directory of Open Access Journals (Sweden)

    Zhou Bing-rong

    2012-11-01

    Full Text Available Abstract Background The purpose of this study was to investigate the effects and mechanisms of dihydrotestosterone (DHT-induced expression of sterol regulatory element binding protein-1 (SREBP-1, and the synthesis and secretion of lipids, in HaCaT cells. HaCaT cells were treated with DHT and either the phosphoinositide 3-kinase inhibitor LY294002 or the extracellular-signal-regulated kinase (ERK inhibitor PD98059. Real time-PCR, Western blot, Oil Red staining and flow cytometry were employed to examine the mRNA and protein expressions of SREBP-1, the gene transcription of lipid synthesis, and lipid secretion in HaCaT cells. Findings We found that DHT upregulated mRNA and protein expressions of SREBP-1. DHT also significantly upregulated the transcription of lipid synthesis-related genes and increased lipid secretion, which can be inhibited by the addition of LY294002. Conclusions Collectively, these results indicate that DHT induces SREBP-1 expression and lipogenesis in HaCaT cells via activation of the phosphoinositide 3-kinase/Akt Pathway.

  16. Part II: crystalline fluorapatite-coated hydroxyapatite implant material: a dog study with histologic comparison of osteogenesis seen with FA-coated HA grafting material versus HA controls: potential bacteriostatic effect of fluoridated HA.

    Science.gov (United States)

    Nordquist, William D; Okudera, Hajima; Kitamura, Yutaka; Kimoto, Kazunari; Okudera, Toshimitsu; Krutchkoff, David J

    2011-01-01

    Success of osteogenesis in bone graft procedures can be enhanced by inhibiting oral bacterial infections through the use of prophylactic bacteriostatic fluoride within the grafting environment. Ideally, the fluoride ion should be chemically sequestered and thus unavailable unless needed at times during the process of early infection. As fluoride within fluorapatite is tightly bound at neutral pH and becomes available only during acidic conditions, fluorapatite is an ideal store for the fluoride ion which becomes released for bacteriostasis only during an acidic environment found with incipient bacterial infection. The purpose of this investigation was to compare the histologic properties of new bone formed surrounding fluorapatite (FA)-coated microcrystalline hydroxyapatite (HA) grafting material with comparable bone formed following the use of control HA material (OsteoGen, Impladent, Ltd, Holliswood, NY). The results of histologic analysis within dog studies here showed no detectable difference in new bone following therapeutic grafting procedures using each of the above 2 mineral coatings.

  17. Influenza bivalent vaccine comprising recombinant H3 hemagglutinin (HA) and H1 HA containing replaced H3 hemagglutinin transmembrane domain exhibited improved heterosubtypic protection immunity in mice.

    Science.gov (United States)

    Liu, Qiliang; Xue, Chunyi; Zheng, Jing; Liu, Kang; Wang, Yang; Wei, Ying; Liu, George Dacai; Cao, Yongchang

    2015-07-31

    Influenza caused by infection of influenza viruses is still a leading cause of morbidity and mortality in human. Vaccination is the main defense against influenza virus, but current influenza trivalent or quatrivalent vaccines (TIV/QIV) would lose their effectiveness when vaccine strains are mismatched with circulating strains. Our early study showed that recombinant influenza Hx-TM HA proteins containing H3 HA transmembrane domain(TM) had improved immunogenicity and heterosubtypic protection over corresponding wild-type Hx-WT HA proteins. In present study, bivalent vaccines containing H3-WT+Hx-TM were investigated for their immune responses and heterosubtypic protection immunities. The data showed that the bivalent vaccines containing H3-WT and H5-TM or H1-TM had improved immune responses and heterosubtypic protection over the bivalent vaccines containing H3-WT and H5-WT or H1-WT respectively. These results demonstrated that the improved immune responses and heterosubtypic protection of Hx-TM HA proteins could be translated into bivalent vaccines, suggesting a feasible strategy of improving the immune responses and heterosubtypic protection of influenza multivalent vaccines such as TIV and QIV.

  18. Enhanced lubrication on tissue and biomaterial surfaces through peptide-mediated binding of hyaluronic acid.

    Science.gov (United States)

    Singh, Anirudha; Corvelli, Michael; Unterman, Shimon A; Wepasnick, Kevin A; McDonnell, Peter; Elisseeff, Jennifer H

    2014-10-01

    Lubrication is key for the efficient function of devices and tissues with moving surfaces, such as articulating joints, ocular surfaces and the lungs. Indeed, lubrication dysfunction leads to increased friction and degeneration of these systems. Here, we present a polymer-peptide surface coating platform to non-covalently bind hyaluronic acid (HA), a natural lubricant in the body. Tissue surfaces treated with the HA-binding system exhibited higher lubricity values, and in vivo were able to retain HA in the articular joint and to bind ocular tissue surfaces. Biomaterials-mediated strategies that locally bind and concentrate HA could provide physical and biological benefits when used to treat tissue-lubricating dysfunction and to coat medical devices.

  19. Enhanced lubrication on tissue and biomaterial surfaces through peptide-mediated binding of hyaluronic acid

    Science.gov (United States)

    Singh, Anirudha; Corvelli, Michael; Unterman, Shimon A.; Wepasnick, Kevin A.; McDonnell, Peter; Elisseeff, Jennifer H.

    2014-10-01

    Lubrication is key for the efficient function of devices and tissues with moving surfaces, such as articulating joints, ocular surfaces and the lungs. Indeed, lubrication dysfunction leads to increased friction and degeneration of these systems. Here, we present a polymer-peptide surface coating platform to non-covalently bind hyaluronic acid (HA), a natural lubricant in the body. Tissue surfaces treated with the HA-binding system exhibited higher lubricity values, and in vivo were able to retain HA in the articular joint and to bind ocular tissue surfaces. Biomaterials-mediated strategies that locally bind and concentrate HA could provide physical and biological benefits when used to treat tissue-lubricating dysfunction and to coat medical devices.

  20. In-capillary detection of fast antibody-peptide binding using fluorescence coupled capillary electrophoresis.

    Science.gov (United States)

    Qin, Yuqin; Qiu, Lin; Qin, Haifang; Ding, Shumin; Liu, Li; Teng, Yiwan; Chen, Yao; Wang, Cheli; Li, Jinchen; Wang, Jianhao; Jiang, Pengju

    2016-01-01

    Herein, we report a technique for detecting the fast binding of antibody-peptide inside a capillary. Anti-HA was mixed and interacted with FAM-labeled HA tag (FAM-E4 ) inside the capillary. Fluorescence coupled capillary electrophoresis (CE-FL) was employed to measure and record the binding process. The efficiency of the antibody-peptide binding on in-capillary assays was found to be affected by the molar ratio. Furthermore, the stability of anti-HA-FAM-E4 complex was investigated as well. The results indicated that E4 YPYDVPDYA (E4) or TAMRA-E4 YPYDVPDYA (TAMRA-E4) had the same binding priorities with anti-HA. The addition of excess E4 or TAMRA-E4 could lead to partial dissociation of the complex and take a two-step mechanism including dissociation and association. This method can be applied to detect a wide range of biomolecular interactions.

  1. Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Aina, Valentina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Bergandi, Loredana, E-mail: loredana.bergandi@unito.it [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy); Lusvardi, Gigliola; Malavasi, Gianluca [Department of Chemical and Geological Sciences, Università di Modena and Reggio Emilia, Via Campi 183, 41125 Modena (Italy); Imrie, Flora E.; Gibson, Iain R. [School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD (United Kingdom); Cerrato, Giuseppina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Ghigo, Dario [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy)

    2013-04-01

    A series of Sr-substituted hydroxyapatites (HA), of general formula Ca{sub (10−x)}Sr{sub x}(PO{sub 4}){sub 6}(OH){sub 2}, where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl{sub 2,} in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in

  2. Label-free detection and characterization of the binding of hemagglutinin protein and broadly neutralizing monoclonal antibodies using terahertz spectroscopy

    Science.gov (United States)

    Sun, Yiwen; Zhong, Junlan; Zhang, Cunlin; Zuo, Jian; Pickwell-MacPherson, Emma

    2015-03-01

    Hemagglutinin (HA) is the main surface glycoprotein of the influenza A virus. The H9N2 subtype influenza A virus is recognized as the most possible pandemic strain as it has crossed the species barrier, infecting swine and humans. We use terahertz spectroscopy to study the hydration shell formation around H9 subtype influenza A virus's HA protein (H9 HA) as well as the detection of antigen binding of H9 HA with the broadly neutralizing monoclonal antibody. We observe a remarkable concentration dependent nonlinear response of the H9 HA, which reveals the formation process of the hydration shell around H9 HA molecules. Furthermore, we show that terahertz dielectric properties of the H9 HA are strongly affected by the presence of the monoclonal antibody F10 and that the terahertz dielectric loss tangent can be used to detect the antibody binding at lower concentrations than the standard ELISA test.

  3. Fabrication and evaluation of porous Ti–HA bio-nanomaterial by leaching process

    Directory of Open Access Journals (Sweden)

    A.M. Omran

    2015-05-01

    Full Text Available A porous surface of Ti–HA composite was successfully fabricated by pulsed current activated sintering (PCAS, followed by leaching using diluted H3PO4. The Ti and HA powders were mixed at different contents of the HA, Ti-5, 10, 30 and 40 wt% HA powders. The mixed powders were pressed in a coated graphite die using pulsed current activated sintering (PCAS under pressure of 60 MPa at temperature of 1000 °C for 5 min. The sintered Ti–HA specimens were immersed in the eight kinds of leaching solutions at room temperature for 24 h. The leached specimen’s surfaces were characterized using XRD, SEM, EDX and Rockwell hardness. The XRD patterns after sintering show that many phases were detected at the sintered specimen surfaces such as; Ti2O, CaO, CaTiO3, TixPy in addition to the remaining Ti and HA. Furthermore, the high concentration H3PO4 leaching solution is more efficient than the low concentration. Also the produced porous surfaces of Ti–HA materials containing more than 30% HA have a low relative density and hardness than the commercial Ti–6Al–4V ELI alloy. In a word, the presence of porous surface coated by HA will promote the nucleation of the biological apatite created with the human tissue and increase the bonding between them. So, the produced porous materials are considered so easy for the muscle cells to permeate after transplanted with high coherence.

  4. Inhibitory action of docetaxel on the proliferation of HeLa and SiHa cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Objective To study the inhibitory action of docetaxel(DOC)on the proliferation of HeLa and SiHa cells.Methods Cell morphological changes were observed with inverted phase contrast microscope.MTT was adopted to test and calculate the cell inhibition ratio.Flow cytometry was used to detect cell cycle.Results DOC had an obvious concentration-dependent inhibitory effect on the proliferation of both HeLa and SiHa cells.The inhibition ratio of DOC on SiHa was significantly higher than that on HeLa(P<0.05).DOC blo...

  5. Tribological Properties of PVA-H Composites Reinforced by Nano-HA Particles

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The friction and wear behaviors of tribological mechanical components were studied on a four-ball tester under dry conditions, and the wear mechanism was analyzed by observed worn surface using a scanning electron microscope (SEM). It was found that the friction and wear properties were improved by the addition of nano HA particles. The composite containing 1 wt% nano HA had the optimum friction coefficient. It is also found that the addition of nano HA increases the wear resistance of pure PVA-H and PVA-H composites.

  6. A Study on HA Titanium Surface with Atomic Force Microscope (AFM)

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Three kinds of titanium surface especially the HA surface are analyzed. Titanium was treated by 3 kinds of methods that were acid & alkali, calcic solution and apatite solution. Samples were observed by optic microscope and atomic force microscope ( AFM). The typical surface morphology of the acid and alkali group is little holes, and on the two HA surface the tiny protuberances is typical. The surface treated by apatite solution was smoother than the two formers. The rough surface treated with acid and alkali was propitious to Ca + , Pand proteins' adhesion, and the relatively smooth HA surface was of benefit to the cell adhesion.

  7. Prediction of IOI-HA Scores Using Speech Reception Thresholds and Speech Discrimination Scores in Quiet

    DEFF Research Database (Denmark)

    Brännström, K Jonas; Lantz, Johannes; Nielsen, Lars Holme

    2014-01-01

    BACKGROUND: Outcome measures can be used to improve the quality of the rehabilitation by identifying and understanding which variables influence the outcome. This information can be used to improve outcomes for clients. In clinical practice, pure-tone audiometry, speech reception thresholds (SRTs......), and speech discrimination scores (SDSs) in quiet or in noise are common assessments made prior to hearing aid (HA) fittings. It is not known whether SRT and SDS in quiet relate to HA outcome measured with the International Outcome Inventory for Hearing Aids (IOI-HA). PURPOSE: The aim of the present study...

  8. Hepatic and renal extraction of circulating type III procollagen amino-terminal propeptide and hyaluronan in pig

    DEFF Research Database (Denmark)

    Bentsen, K D; Henriksen, Jens Henrik Sahl; Boesby, S

    1989-01-01

    of different PIIINP-related antigens. One was the PIIINP RIA Kit, which measures the intact propeptide. The other was the PIIINP Fab assay, in which the antibody has an equal affinity to the intact propeptide and to smaller fragments, of which the latter constitutes most of the antigenic activity in serum...... fragments. No gastrointestinal extraction of any of the tested substances could be demonstrated. Only smaller PIIINP fragments (such as the col 1 fragment) were extracted by the kidneys (the extraction ratio in the PIIINP Fab assay was 0.19). The renal extraction ratio of HA was 0.14. The amounts of PIIINP...... fragments and of HA extracted by the kidneys were 50- and 3-times the amounts found in urine, respectively, indicating that the col 1 fragment and HA are degraded in the kidneys in addition to urinary excretion. Our results suggest a dynamic turnover of connective tissue-related components with a fast...

  9. Investigation of the inhibitory effects of HA-1077 and Y-32885 on the translocation of PKCβI, PKCβII and PKCζ in human neutrophils

    Directory of Open Access Journals (Sweden)

    Xavier Siomboing

    2001-01-01

    Full Text Available To transmit the information inside the cell, one possibility is the action of an enzyme called kinase that phosphorylates other proteins. To study these enzymes, chemical compound synthesis was needed to know the function and the mechanism of activation. The major difficulty is creating a specific molecule for one kinase. In this study, we test the action of Rho-kinase inhibitors (HA-1077 and Y-32885 on protein kinase C (PKC in the respiratory burst in the human polymorphonuclear neutrophils. We have shown that these compounds could inhibit the anion superoxide production. To prove their action on PKC, we have shown a decrease of binding of a specific ligand (phorbol-12,13-dibutyrate with each inhibitor. During its activation, PKC was translocated from the cytoplasm to the plasmic membrane. We have also shown an inhibition of this translocation, proving an inhibition of PKC by HA-1077 and Y-32885.

  10. Metal Ion-dependent Heavy Chain Transfer Activity of TSG-6 Mediates Assembly of the Cumulus-Oocyte Matrix.

    Science.gov (United States)

    Briggs, David C; Birchenough, Holly L; Ali, Tariq; Rugg, Marilyn S; Waltho, Jon P; Ievoli, Elena; Jowitt, Thomas A; Enghild, Jan J; Richter, Ralf P; Salustri, Antonietta; Milner, Caroline M; Day, Anthony J

    2015-11-27

    The matrix polysaccharide hyaluronan (HA) has a critical role in the expansion of the cumulus cell-oocyte complex (COC), a process that is necessary for ovulation and fertilization in most mammals. Hyaluronan is organized into a cross-linked network by the cooperative action of three proteins, inter-α-inhibitor (IαI), pentraxin-3, and TNF-stimulated gene-6 (TSG-6), driving the expansion of the COC and providing the cumulus matrix with its required viscoelastic properties. Although it is known that matrix stabilization involves the TSG-6-mediated transfer of IαI heavy chains (HCs) onto hyaluronan (to form covalent HC·HA complexes that are cross-linked by pentraxin-3) and that this occurs via the formation of covalent HC·TSG-6 intermediates, the underlying molecular mechanisms are not well understood. Here, we have determined the tertiary structure of the CUB module from human TSG-6, identifying a calcium ion-binding site and chelating glutamic acid residue that mediate the formation of HC·TSG-6. This occurs via an initial metal ion-dependent, non-covalent, interaction between TSG-6 and HCs that also requires the presence of an HC-associated magnesium ion. In addition, we have found that the well characterized hyaluronan-binding site in the TSG-6 Link module is not used for recognition during transfer of HCs onto HA. Analysis of TSG-6 mutants (with impaired transferase and/or hyaluronan-binding functions) revealed that although the TSG-6-mediated formation of HC·HA complexes is essential for the expansion of mouse COCs in vitro, the hyaluronan-binding function of TSG-6 does not play a major role in the stabilization of the murine cumulus matrix.

  11. Belgia rahvuspüha puhul kuuleb Eestis kammermuusikat / Maarja Pehk

    Index Scriptorium Estoniae

    Pehk, Maarja

    2007-01-01

    21. juulil on Belgia Kuningriigil rahvuspüha. Suursaadik Pierre Clement Dubuisson tutvustab sel puhul belgia kultuuri kolme kontserdi kaudu. Sel aastal tutvustab saatkond Belgia kultuuri ka koostöös Pimedate Ööde filmifestivaliga

  12. Dagestan arutleb üha valjemalt šariaadi kehtestamise üle / Jaanus Piirsalu

    Index Scriptorium Estoniae

    Piirsalu, Jaanus, 1973-

    2010-01-01

    Dagestanis arutletakse üha rohkem selle üle, kas ühiskond peaks rohkem islamiseeruma või säilitama ilmaliku elukorralduse. Ekspertide hinnangul järgivad islami usku umbes pooled Dagestani elanikud

  13. Single-dose monomeric HA subunit vaccine generates full protection from influenza challenge

    CSIR Research Space (South Africa)

    Mallajosyula, JK

    2014-03-01

    Full Text Available Recombinant subunit vaccines are an efficient strategy to meet the demands of a possible influenza pandemic, because of rapid and scalable production. However, vaccines made from recombinant hemagglutinin (HA) subunit protein are often of low...

  14. Comparative study of microstructural remodification to porous β-TCP and HA in rabbits

    Institute of Scientific and Technical Information of China (English)

    SUN Jiao; SHEN QingYi; LU JianXi

    2009-01-01

    emodeling pattern resulted from bone formation and scaffold resorption was significantly different for the two bioceramics.The results demonstrated that the 75% porous β-TCP was more suitable for new bone remodification than HA scaffold.

  15. Metallpitsid Tallinna Püha Johannese hospidali (Jaani seegi) kalmistu haualeidudes / Sari Marjut Rainne

    Index Scriptorium Estoniae

    Rainne, Sari Marjut

    2010-01-01

    Tallinna Püha Johannese hospidali (Jaani seegi) kalmistualal toimunud arheoloogilistelt kaevamistelt leitud metallpitsidest. Ülevaade põhiliselt 18. sajandist pärit peakatete külge kinnitatud pitside materjaliuuringu tulemustest ja konserveerimisest

  16. Morphology, Structure and Biodegradability of Hollow HA Microspheres Obtained by Plasma Spraying

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The spraying-dried HA (ASD) was employed. ASD was plasma-sprayed onto ice to obtain hollow HA microspheres. The particle size of the sample was determined with a particle size analyzer. The morphology and structure of the samples were measured by scanning electron microscope and X-ray powder diffraction.The in vitro biodegradability of samples was evaluated by immersion tests in Ringer' s solution (RS) and simulated body fluid ( SBF). The samples were immersed respectively in RS and SBF for a period. The Ca2+ ion concentration in the solutions was determined by Atomic Adsorption Spectrum. By plasma spraying hollow HA microspheres were obtained. The hollow microspheres consisted mainly of low crystalline and amorphous HA, and had better biodegradability.

  17. Neli + püha = kostüüm / Tambet Kaugema

    Index Scriptorium Estoniae

    Kaugema, Tambet

    1998-01-01

    Tallinnas Niguliste muuseum-kontserdisaalis kostüümidraama 'Neli + püha', mille korraldasid Jaanus Orgusaar, Ene Liis Semper, Aldo Järvsoo ja Tanel Veenre. Etendus toimus 'Barclay Atmosphere Art Is Everywhere' sarjas

  18. Neli + püha = kostüüm / Tambet Kaugema

    Index Scriptorium Estoniae

    Kaugema, Tambet

    1998-01-01

    Tallinnas Niguliste muuseum-kontserdisaalis kostüümidraama 'Neli + püha', mille korraldasid Jaanus Orgusaar, Ene Liis Semper, Aldo Järvsoo ja Tanel Veenre. Etendus toimus 'Barclay Atmosphere Art Is Everywhere' sarjas

  19. Metallpitsid Tallinna Püha Johannese hospidali (Jaani seegi) kalmistu haualeidudes / Sari Marjut Rainne

    Index Scriptorium Estoniae

    Rainne, Sari Marjut

    2010-01-01

    Tallinna Püha Johannese hospidali (Jaani seegi) kalmistualal toimunud arheoloogilistelt kaevamistelt leitud metallpitsidest. Ülevaade põhiliselt 18. sajandist pärit peakatete külge kinnitatud pitside materjaliuuringu tulemustest ja konserveerimisest

  20. New therapeutic agent for radiation synovectomy - preparation of {sup 166}Ho-EDTMP-HA particle

    Energy Technology Data Exchange (ETDEWEB)

    Bai, H.; Jin, X.; Du, J.; Wang, F.; Chen, D.; Fan, H.; Cheng, Z.; Zhang, J. [China Institute of Atomic Energy, Beijing (Switzerland). Isotope Department

    1997-10-01

    In order to prepare new therapeutical agent for radiation synovectomy, Hydroxyapatite (HA) was labelled with {sup 166}Ho by EDTMP that had high affinity to HA particles. Radiolabelling of HA particles was divided into two steps, {sup 166}Ho-EDTMP was prepared first; then mixed with HA particles completely and vibrated for 15 minutes on the micromixer at room temperature, washed 3 times with deionized water. Radiolabelling particle was separated from free {sup 166}Ho via centrifugation to determine its radiolabelling efficiency. {sup 166}Ho-EDTMP-HA and {sup 166}Ho-EDTMP were injected into knee joint of normal rabbits respectively, every group was killed at different time postinjection, took out major organ and collected urine and blood, then weighted and determined their radio counts. HA particles, as a natural component of bone was known to have good compatibility with soft tissue and biodegrade into calcium and phosphate in vivo. It was readily prepared from common chemical and formed into particles of desired size range in a controlled process, it had high stability in vitro and vivo. Radiolabelling of HA particle with {sup 166}Ho by EDTMP was simple to perform and provides an excellent labelling yield that was more than 95% under the optimal labelling condition. The optimal labelling condition at room temperature was pH 6.0-8.0 and vibration time 15 minutes. The absorbed capacity of HA particle was 5 mg Ho/g HA particle and size of radiolabelling particle was at range of 2-5,{mu}m that is suitable for therapy of radiation synovectomy. {sup 166}Ho-EDTMP-HA particle demonstrated high in vitro stability in either normal saline or 1% BSA solution, but instability under extremely acidic condition (pH 1-2). The control studies performed with {sup 166}Ho-EDTMP not bound to HA particle provided information on the distribution of radioactivity that would occur upon leakage of the radiochemical compound from joint. Its short half-life, its extremely low leakage from the

  1. Fractal analysis of polyferric chloride-humic acid (PFC-HA) flocs in different topological spaces.

    Science.gov (United States)

    Wang, Yili; Lu, Jia; Baiyu, Du; Shi, Baoyou; Wang, Dongsheng

    2009-01-01

    The fractal dimensions in different topological spaces of polyferric chloride-humic acid (PFC-HA) flocs, formed in flocculating different kinds of humic acids (HA) water at different initial pH (9.0, 7.0, 5.0) and PFC dosages, were calculated by effective density-maximum diameter, image analysis, and N2 absorption-desorption methods, respectively. The mass fractal dimensions (Df) of PFC-HA flocs were calculated by bi-logarithm relation of effective density with maximum diameter and Logan empirical equation. The Df value was more than 2.0 at initial pH of 7.0, which was 11% and 13% higher than those at pH 9.0 and 5.0, respectively, indicating the most compact flocs formed in flocculated HA water at initial pH of 7.0. The image analysis for those flocs indicates that after flocculating the HA water at initial pH greater than 7.0 with PFC flocculant, the fractal dimensions of D2 (logA vs. logdL) and D3 (logVsphere VS. logdL) of PFC-HA flocs decreased with the increase of PFC dosages, and PFC-HA flocs showed a gradually looser structure. At the optimum dosage of PFC, the D2 (logA vs. logdL) values of the flocs show 14%-43% difference with their corresponding Df, and they even had different tendency with the change of initial pH values. However, the D2 values of the flocs formed at three different initial pH in HA solution had a same tendency with the corresponding Dr. Based on fractal Frenkel-Halsey-Hill (FHH) adsorption and desorption equations, the pore surface fractal dimensions (Ds) for dried powders of PFC-HA flocs formed in HA water with initial pH 9.0 and 7.0 were all close to 2.9421, and the Ds values of flocs formed at initial pH 5.0 were less than 2.3746. It indicated that the pore surface fractal dimensions of PFC-HA flocs dried powder mainly show the irregularity from the mesopore-size distribution and marcopore-size distribution.

  2. Sequence diversity within the HA-1 gene as detected by melting temperature assay without oligonucleotide probes

    Directory of Open Access Journals (Sweden)

    Mattiuz Pier

    2005-10-01

    Full Text Available Abstract Background The minor histocompatibility antigens (mHags are self-peptides derived from common cellular proteins and presented by MHC class I and II molecules. Disparities in mHags are a potential risk for the development of graft-versus-host disease (GvHD in the recipients of bone marrow from HLA-identical donors. Two alleles have been identified in the mHag HA-1. The correlation between mismatches of the mHag HA-1 and GvHD has been suggested and methods to facilitate large-scale testing were afterwards developed. Methods We used sequence specific primer (SSP PCR and direct sequencing to detect HA-1 gene polymorphisms in a sample of 131 unrelated Italian subjects. We then set up a novel melting temperature (Tm assay that may help identification of HA-1 alleles without oligonucleotide probes. Results We report the frequencies of HA-1 alleles in the Italian population and the presence of an intronic 5 base-pair deletion associated with the immunogeneic allele HA-1H. We also detected novel variable sites with respect to the consensus sequence of HA-1 locus. Even though recombination/gene conversion events are documented, there is considerable linkage disequilibrium in the data. The gametic associations between HA-1R/H alleles and the intronic 5-bp ins/del polymorphism prompted us to try the Tm analysis with SYBR® Green I. We show that the addition of dimethylsulfoxide (DMSO during the assay yields distinct patterns when amplicons from HA-1H homozygotes, HA-1R homozygotes, and heterozygotes are analysed. Conclusion The possibility to use SYBR® Green I to detect Tm differences between allelic variants is attractive but requires great caution. We succeeded in allele discrimination of the HA-1 locus using a relatively short (101 bp amplicon, only in the presence of DMSO. We believe that, at least in certain assets, Tm assays may benefit by the addition of DMSO or other agents affecting DNA strand conformation and stability.

  3. Study of preparation of BG/HA gradient coating on titanium alloy by electrophoretic deposition method

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-ming; HAN Qing-rong; LI Shi-pu; XU Chuan-bo

    2001-01-01

    In this paper, a gradient bioactive coating made from modified bioglass (BG) and hydroxyapatite (HA) was prepared by electrophoretic deposition method(EPD)on the surface of titanium alloy. Strong bonding between the matrix and BG/HA gradient coating was got by sintering. Crystal composition of the coating was analyzed by XRD. The characteristics of surface and cross section of the coating were observed by SEM. Adhesive strength of the coating was tested by pull method. The optimizing technological parameters were determined.

  4. Fabrication of Ti/HA composite and functionally graded implant by three-dimensional printing.

    Science.gov (United States)

    Qian, Chao; Zhang, Fuqiang; Sun, Jian

    2015-01-01

    The aim of this study is to evaluate the feasibility of fabricating titanium(Ti)/hydroxyapatite(HA) composite and functionally graded implant by three-dimensional printing (3DP) technology. Nano-scale Ti and HA powders were mixed at the ratio of 8:2 and prepared with water-soluble binder. The Ti/HA composite CAD model was designed to be in cylinder shape (25 mm in diameter, 20 mm in height) with the 100% bond area in each layer. The functionally graded implant was 25 mm in diameter and 10 mm in height with two segments. The upper segment was composed of 100% Ti in each layer, whereas the lower was composed of 80%Ti/20%HA. The composite and functionally graded implant were fabricated by 3DP and sintered at 1200°C under protective argon atmosphere. There occurred a chemical reaction between Ti and HA, in which new resultants of Ca3(PO4)2, CaTiO3, TiO2 and CaO were created. The sintered Ti/HA composite had the aperture size from 50 to 150 μm and the compressive strength of 184.3±27.1 MPa. The result of this study demonstrated that it was feasible to fabricate Ti/HA composite and functionally graded implant by 3DP technology. The microstructure and mechanical properties of Ti/HA composite and functionally graded implant were conductive to bone cell ingrowth, resulting in the wide application of this biocomposite.

  5. 3D-printed scaffolds based on PLA/HA nanocomposites for trabecular bone reconstruction

    Science.gov (United States)

    Niaza, K. V.; Senatov, F. S.; Kaloshkin, S. D.; Maksimkin, A. V.; Chukov, D. I.

    2016-08-01

    In the present work porous PLA scaffolds filled with micro- and nano- HA were studied. Both composites with micro- and nano-HA were obtained by extrusion in the same conditions. Scaffolds were obtained by 3D-printing by fused filament fabrication method. Structure of porous scaffolds was pre-modeled by computer software. Compression and three - point flexural tests were used to study mechanical properties of the scaffolds.

  6. Magneto-optical and catalytic properties of Fe3O4@HA@Ag magnetic nanocomposite

    Science.gov (United States)

    Amir, Md.; Güner, S.; Yıldız, A.; Baykal, A.

    2017-01-01

    Fe3O4@HA@Ag magnetic nanocomposites (MNCs) were successfully synthesized by the simple reflux method for the removal of azo dyes from the industrial aqueous media. Fe3O4@HA@AgMNCs exhibited high catalytic activity to reduce MB within 20 min from the waste water. The obtained materials were characterized by the means of different techniques. Powder X-ray diffraction (XRD) analysis confirmed the single-phase of Fe3O4 spinel structure. SEM and TEM analysis indicated that Fe3O4@HA@AgMNCs were nanoparticles like structure with small agglomeration. TG result showed that the products contained 9% of HA. The characteristic peaks of HA at 1601 cm-1 and 1703 cm-1 was observed by the means of FT-IR spectra of Fe3O4@HA@AgMNCs. The hysteresis (σ-H) curves revealed Fe3O4@HA@Ag MNCs exhibit a typical superparamagnetic characteristic with a saturation magnetization of 59.11 emu/g and measured magnetic moment is 2.45 μB. The average magnetic particle dimension (Dmag) is 13.25 nm. In accordance, the average crystallite and particle dimensions were obtained as 11.50 nm and 13.10 nm from XRD and TEM measurements, respectively. Magnetocrystalline anisotropy was offered as uniaxial and calculated effective anisotropy constant (Keff) is 2.96×105 Erg/g. The blocking temperature was estimated as 522 K. The size-dependent saturation magnetization suggests the existence of a magnetically dead layer as 0.793 nm for Fe3O4@HA@Ag MNCs. The UV-vis diffuse reflectance spectroscopy (DRS) and Kubelka-Munk theory were applied to determine the optical properties of powder samples. The direct optical energy band gap (Eg) values were estimated from Tauc plots between 1.62 eV and 2.12 eV.

  7. Polyethylene oxide (PEO)-hyaluronic acid (HA) nanofibers with kanamycin inhibits the growth of Listeria monocytogenes.

    Science.gov (United States)

    Ahire, J J; Robertson, D D; van Reenen, A J; Dicks, L M T

    2017-02-01

    Listeria monocytogenes is well known to cause prosthetic joint infections in immunocompromised patients. In this study, polyethylene oxide (PEO) nanofibers, containing kanamycin and hyaluronic acid (HA), were prepared by electrospinning at a constant electric field of 10kV. PEO nanofibers spun with 0.2% (w/v) HA and 1% (w/v) kanamycin had a smooth, bead-free structure at 30-35% relative humidity. The average diameter of the nanofibers was 83±20nm. Attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy indicated that kanamycin was successfully incorporated into PEO/HA matrix. The presence of kanamycin affects the thermal properties of PEO/HA nanofibers, as shown by differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA). The kanamycin-PEO-HA nanofibers (1mg; 47±3μg kanamycin) inhibited the growth of L. monocytogenes EDGe by 62%, as compared with PEO-HA nanofibers, suggesting that it may be used to coat prosthetic implants to prevent secondary infections.

  8. A Study of Hybrid Composite Hydroxyapatite (HA-Geopolymers as a Material for Biomedical Application

    Directory of Open Access Journals (Sweden)

    Saleha

    2017-01-01

    Full Text Available The main purpose of this research is to study the physical properties and microstructure characters of hybrid composites HA-geopolymers as a material for biomedical application. Hybrid composite HA–geopolymers were produced through alkaline activation method of metakaolin as a matrix and HA as the filler. HA was synthesized from eggshell particles by using a precipitation method. The addition of HA in metakaolin paste was varied from 0.5%, 1.0%, 1.5%, and 2.0% relative the weight of metakaolin. FTIR was used to examine the absorption bands the composites. X-ray diffraction (XRD was used to study the crystal structure of the starting and the resulting materials. Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS was used to investigate the surface morphology of the composites. The thermal properties of the samples was examined by means of Differential Scanning Calorimetry (DSC. Capacitance measurement was conducted to investigate the bioactive properties of HA. The study results suggest that hybrid composite HA-geopolymers has a potential to be applied as a biomedical such as biosensor material.

  9. Antibacterial activation of hydroxyapatite (HA) with controlled porosity by different antibiotics.

    Science.gov (United States)

    Chai, F; Hornez, J-C; Blanchemain, N; Neut, C; Descamps, M; Hildebrand, H F

    2007-11-01

    In order to prevent the increasing frequency of per-operative infections, bioceramics can be loaded with anti-bacterial agents, which will release with respect to their chemical characteristics. A novel hydroxyapatite (HA) was elaborated with specific internal porosities for using as a bone-bioactive antibiotic (ATB) carrier material. UV spectrophotometry and bacteria inhibition tests were performed for testing the ATB adsorption and the microbiological effectiveness after loading with different antibiotics. The impregnation time, ATB impregnating concentration, impregnation condition and other factors, which might influence the ATB loading effect, were studied by exposure to different releasing solvents and different pathogenic bacteria: Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. It clearly showed that the facility of ATB loading on this porous HA is even possible just under simple non-vacuum impregnation conditions in a not-so-long impregnating interval. The results also showed that, for all three types of ATB (vancomycin, ciprofloxacin and gentamicin), adsorbed amount on the micro-porous HA were hugely higher than that on dense HA. The micro-porosity of test HA had also significantly prolonged the release time of antibiotics even under mimic physiological conditions. Furthermore, it also has primarily proved by a pilot test that the antibacterial efficiency of crude micro-porous HA could be further significantly improved by other methods of functionalization such as cold plasma technique.

  10. Crystallization and preliminary X-ray analysis of the HA3 component of Clostridium botulinum type C progenitor toxin

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Toshio; Tonozuka, Takashi; Kotani, Mao; Obata, Kanae [Department of Applied Biological Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Oguma, Keiji [Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558 (Japan); Nishikawa, Atsushi, E-mail: nishikaw@cc.tuat.ac.jp [Department of Applied Biological Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); CREST, Japan Science and Technology Agency (Japan)

    2007-12-01

    HA3, a 70 kDa haemagglutinating protein, is a precursor form of HA3a and HA3b, the subcomponents of Clostridium botulinum type C 16S progenitor toxin. In this report, recombinant HA3 protein was overexpressed in Escherichia coli, purified and crystallized. HA3, a 70 kDa haemagglutinating protein, is a precursor form of HA3a and HA3b, the subcomponents of Clostridium botulinum type C 16S progenitor toxin. In this report, recombinant HA3 protein was overexpressed in Escherichia coli, purified and crystallized. Diffraction data were collected to 2.6 Å resolution and the crystal belonged to the hexagonal space group P6{sub 3}. Matthews coefficient and self-rotation function calculations indicate that there is probably one molecule of HA3 in the asymmetric unit. A search for heavy-atom derivatives has been undertaken.

  11. 改性MWNTs/纳米HA/PLA骨修复材料的制备%Preparation of bone repair material of modified-MWNTs/nano-HA/PLA

    Institute of Scientific and Technical Information of China (English)

    张晓明; 王洪艳; 李俊锋

    2008-01-01

    采用气相氧化法及液相氧化法制备了带有羧基的多壁碳纳米管(MWNTs-COOH).在超声波辅助下,通过原位合成法将纳米羟基磷灰石(nano-HA)包覆在MWNTs-COOH上,得到纳米复合材料(MWNTs-COO/nano-HA),该纳米复合材料与聚乳酸(PLA)熔融共混成功制备出MWNTs-COO/nano-HA/PLA骨修复材料.经过FT-IR、XRD、TEM和电子拉力等分析表明,MWNTs-COOH完全被nano-HA包覆,MWNTs-COO/nano-HA复合材料颗粒完全达到纳米级.实验考察了复合材料中不同含量的MWNTs-COOH和MWNTs-COO/nano-HA对力学性能的影响,确定了MWNTs-COOH和MWNT-COO/nano-HA在材料中的最佳比例.

  12. Possible detection of the stellar donor or remnant for the type Iax supernova 2008ha

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Ryan J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); McCully, Curtis; Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Bildsten, Lars [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Fong, Wen-fai [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Narayan, Gautham [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719-4933 (United States); Rest, Armin [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Stritzinger, Maximilian D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark)

    2014-09-01

    Type Iax supernovae (SNe Iax) are thermonuclear explosions that are related to SNe Ia, but are physically distinct. The most important differences are that SNe Iax have significantly lower luminosity (1%-50% that of typical SNe Ia), lower ejecta mass (∼0.1-0.5 M {sub ☉}), and may leave a bound remnant. The most extreme SN Iax is SN 2008ha, which peaked at M{sub V} = –14.2 mag, about 5 mag below that of typical SNe Ia. Here, we present Hubble Space Telescope (HST) images of UGC 12682, the host galaxy of SN 2008ha, taken 4.1 yr after the peak brightness of SN 2008ha. In these deep, high-resolution images, we detect a source coincident (0.86 HST pixels; 0.''043; 1.1σ) with the position of SN 2008ha with M {sub F814W} = –5.4 mag. We determine that this source is unlikely to be a chance coincidence, but that scenario cannot be completely ruled out. If this source is directly related to SN 2008ha, it is either the luminous bound remnant of the progenitor white dwarf (WD) or its companion star. The source is consistent with being an evolved >3 M {sub ☉} initial mass star, and is significantly redder than the SN Iax 2012Z progenitor system, the first detected progenitor system for a thermonuclear SN. If this source is the companion star for SN 2008ha, there is a diversity in SN Iax progenitor systems, perhaps related to the diversity in SN Iax explosions. If the source is the bound remnant of the WD, it must have expanded significantly. Regardless of the nature of this source, we constrain the progenitor system of SN 2008ha to have an age of <80 Myr.

  13. Arecoline suppresses HaCaT cell proliferation through cell cycle regulatory molecules.

    Science.gov (United States)

    Zhou, Zhong-Su; Li, Ming; Gao, Feng; Peng, Jie-Ying; Xiao, Hai-Bo; Dai, Li-Xia; Lin, Shi-Rong; Zhang, Rui; Jin, Long-Yu

    2013-06-01

    Betel nut chewing is the most common cause of oral submucous fibrosis (OSF). Arecoline is the main component of the betel nut, and is associated with the occurrence and development of OSF through cytotoxicity, genotoxicity and DNA damage. Similar types of stimuli elicit differential responses in different cells. In the present study, we investigated the effects of arecoline on the HaCaT epithelial and Hel fibroblast cell lines. The data showed that arecoline affected HaCaT cell morphology. MTT assay revealed that arecoline suppressed HaCaT cell proliferation. Furthermore, we found that arecoline induced the cell cycle arrest of HaCaT cells. In comparison with the untreated control cells, following treatment with ≥75 µg/ml arecoline an increased percentage of HaCaT cells remained at the G0/G1 phase of the cell cycle, accompanied by a reduced percentage of cells in the S phase. However, arecoline treatment did not significantly alter Hel cell cycle distribution. In the HaCaT epithelial cells, arecoline downregulated expression of the G1/S phase regulatory proteins cyclin D1, CDK4, CDK2, E2F1 as determined by reverse transcription-PCR analysis and western blotting. In summary, arecoline inhibits HaCaT epithelial cell proliferation and survival, in a dose-dependent manner, and cell cycle arrest in the G1/S phase, while this is not obvious in the Hel fibroblast cells. Potentially, our findings may aid in the prevention of arecoline-associated human OSF.

  14. Preparation and bioevaluation of 166Ho labelled hydroxyapatite (HA) particles for radiosynovectomy.

    Science.gov (United States)

    Unni, P R; Chaudhari, P R; Venkatesh, Meera; Ramamoorthy, N; Pillai, M R A

    2002-02-01

    The preparation of 166Ho labeled hydroxy apatite (HA) particles for radiosynovectomy applications is described in this paper. 166Ho was prepared by the irradiation of Ho2O3 at a flux of 1.8 x 10(13) neutrons/cm2/s for about 7 days. The irradiation resulted in the production of approximately 17 GBq of 166Ho activity at the end of six hours post end of bombardment and the corresponding specific activity was approximately 3-4 GBq/mg of Ho. The irradiated target was dissolved in 0.1 N HCl solution. Radionuclidic purity was ascertained by high resolution gamma ray spectrometry. HA particles were synthesized and characterized by X-ray diffractometry. Labeling studies were carried out with and without citric acid as a transchelating agent. Radiochemical yield and purity of the 166Ho-HA particles were ascertained by paper chromatography and by paper electrophoresis techniques. Labeling yield of >98% could be achieved at pH 7, with 40 mg of HA particles and 8.6 microg of Ho. 166Ho-HA particles prepared were stable for 72 h. Bio-evaluation of the 166Ho -HA particles were carried out by injecting approximately 74 MBq dose in 200 microL (approximately 8 mg of 166Ho-HA particles) directly into the arthritis induced knee joints as well as into the healthy knee joints of white New Zealand rabbits. Images of the injected joints of the animals recorded using a gamma camera at regular intervals showed good retention. Blood samples were collected from the animals and activity assayed in a scintillation detector. Experiments were also carried out under identical conditions in normal rabbits. In both the cases, it was observed that there was no significant extra articular leakage of the injected activity over the study period of 96 h post injection.

  15. Engineered HA hydrogel for stem cell transplantation in the brain: Biocompatibility data using a design of experiment approach

    Directory of Open Access Journals (Sweden)

    Lina R. Nih

    2017-02-01

    Full Text Available This article presents data related to the research article “Systematic optimization of an engineered hydrogel allows for selective control of human neural stem cell survival and differentiation after transplantation in the stroke brain” (P. Moshayedi, L.R. Nih, I.L. Llorente, A.R. Berg, J. Cinkornpumin, W.E. Lowry et al., 2016 [1] and focuses on the biocompatibility aspects of the hydrogel, including its stiffness and the inflammatory response of the transplanted organ. We have developed an injectable hyaluronic acid (HA-based hydrogel for stem cell culture and transplantation, to promote brain tissue repair after stroke. This 3D biomaterial was engineered to bind bioactive signals such as adhesive motifs, as well as releasing growth factors while supporting cell growth and tissue infiltration. We used a Design of Experiment approach to create a complex matrix environment in vitro by keeping the hydrogel platform and cell type constant across conditions while systematically varying peptide motifs and growth factors. The optimized HA hydrogel promoted survival of encapsulated human induced pluripotent stem cell derived-neural progenitor cells (iPS-NPCs after transplantation into the stroke cavity and differentially tuned transplanted cell fate through the promotion of glial, neuronal or immature/progenitor states. The highlights of this article include: (1 Data of cell and bioactive signals addition on the hydrogel mechanical properties and growth factor diffusion, (2 the use of a design of Experiment (DOE approach (M.W. 2 Weible and T. Chan-Ling, 2007 [2] to select multi-factorial experimental conditions, and (3 Inflammatory response and cell survival after transplantation.

  16. Engineered HA hydrogel for stem cell transplantation in the brain: Biocompatibility data using a design of experiment approach.

    Science.gov (United States)

    Nih, Lina R; Moshayedi, Pouria; Llorente, Irene L; Berg, Andrew R; Cinkornpumin, Jessica; Lowry, William E; Segura, Tatiana; Carmichael, S Thomas

    2017-02-01

    This article presents data related to the research article "Systematic optimization of an engineered hydrogel allows for selective control of human neural stem cell survival and differentiation after transplantation in the stroke brain" (P. Moshayedi, L.R. Nih, I.L. Llorente, A.R. Berg, J. Cinkornpumin, W.E. Lowry et al., 2016) [1] and focuses on the biocompatibility aspects of the hydrogel, including its stiffness and the inflammatory response of the transplanted organ. We have developed an injectable hyaluronic acid (HA)-based hydrogel for stem cell culture and transplantation, to promote brain tissue repair after stroke. This 3D biomaterial was engineered to bind bioactive signals such as adhesive motifs, as well as releasing growth factors while supporting cell growth and tissue infiltration. We used a Design of Experiment approach to create a complex matrix environment in vitro by keeping the hydrogel platform and cell type constant across conditions while systematically varying peptide motifs and growth factors. The optimized HA hydrogel promoted survival of encapsulated human induced pluripotent stem cell derived-neural progenitor cells (iPS-NPCs) after transplantation into the stroke cavity and differentially tuned transplanted cell fate through the promotion of glial, neuronal or immature/progenitor states. The highlights of this article include: (1) Data of cell and bioactive signals addition on the hydrogel mechanical properties and growth factor diffusion, (2) the use of a design of Experiment (DOE) approach (M.W. 2 Weible and T. Chan-Ling, 2007) [2] to select multi-factorial experimental conditions, and (3) Inflammatory response and cell survival after transplantation.

  17. Intra-articular hyaluronan is without clinical effect in knee osteoarthritis: a multicentre, randomised, placebo-controlled, double-blind study of 337 patients followed for 1 year

    DEFF Research Database (Denmark)

    Jørgensen, Anette; Stengaard-Pedersen, Kristian; Simonsen, Lars Ole;

    2010-01-01

    Objective To examine the long-term efficacy and safety of five intra-articular injections with hyaluronan in knee osteoarthritis. Methods A multicentre, randomised, placebo-controlled double-blind study of 337 patients fulfilling the American College of Rheumatology (ACR) criteria for knee...... efficacy parameter. LFI, pain on walking 50 m based on visual analogue scale (VAS pain 50 m), paracetamol consumption, patients' global assessment, Nottingham health profile, joint effusion and number of responders were secondary efficacy parameters. The efficacy parameters were analysed by intention...... to treat (ITT) and per protocol (PP). All adverse events (AE) were recorded as safety parameters. Results Time to recurrence showed no significant treatment effect (ITT analysis, p = 0.26). Change from baseline in LFI and VAS pain 50 m for the ITT population showed no treatment effect. Paracetamol...

  18. Analyzing binding data.

    Science.gov (United States)

    Motulsky, Harvey J; Neubig, Richard R

    2010-07-01

    Measuring the rate and extent of radioligand binding provides information on the number of binding sites, and their affinity and accessibility of these binding sites for various drugs. This unit explains how to design and analyze such experiments.

  19. Endothelial cell cultured on HA/TCP/chitosan scaffold for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Bachtiar EW

    2011-06-01

    Full Text Available Background: Angiogenesis is crucial for the success of bone reconstruction through tissue engineering. Currently, is still not known the activity of endothelial cells that is responsible for blood vessel formation, cultured in HA/TCP/chitosan scaffold. The ability of the scaffold to facilitate the proliferation and migration of endothelial cell to form blood vessel is essential for cell survival especially in the inner area of the scaffold that is susceptible for cell death if adequate vascularization is not occurred. Purpose: The purpose of this study was to evaluate the porosity of HA/TCP/chitosan scaffold and the biocompatibility of HA/TCP/chitosan scaffold to endothelial cells. Methods: Endothelial cells were isolated from umbilical vein (human umbilical vein endothelial cells/ HUVEC. HA/ TCP/chitosan scaffold was made from two gelling agents and various basic washing solutions. The characteristic of scaffold was examined by scanning electron microscopy. The activity of HUVEC was evaluated by MTT assay. Results: Initial average scaffold porosity size range from 68 μm and increased up to 134 μm after 7 days incubation with 10 mg/L lysozyme. There was no significant difference in the viability of HUVEC incubated with the scaffold compared to control. Conclusion: HA/TCP/chitosan has a good biocompatibility for HUVEC. This condition supports the activity of HUVEC in the scaffold for angiogenesis process, to provide oxygen and nutrient necessary for osteoblast.Latar belakang: Angiogenesis merupakan proses yang penting untuk keberhasilan rekonstruksi tulang melalui rekayasa jaringan. Saat ini, aktifitas sel endotel pembentuk dinding pembuluh darah pada HA/TCP/chitosan scaffold belum diketahui. Kemampuan scaffold sebagai tempat proliferasi dan migrasi sel endotel untuk membentuk pembuluh darah penting untuk kelangsungan hidup sel osteoblast terutama di bagian dalam scaffold. Tujuan: Mengevaluasi porositas HA/TCP/chitosan scaffold serta sifat

  20. Characterization of a small acyl-CoA-binding protein (ACBP) from Helianthus annuus L. and its binding affinities.

    Science.gov (United States)

    Aznar-Moreno, Jose A; Venegas-Calerón, Mónica; Du, Zhi-Yan; Garcés, Rafael; Tanner, Julian A; Chye, Mee-Len; Martínez-Force, Enrique; Salas, Joaquín J

    2016-05-01

    Acyl-CoA-binding proteins (ACBPs) bind to acyl-CoA esters and promote their interaction with other proteins, lipids and cell structures. Small class I ACBPs have been identified in different plants, such as Arabidopsis thaliana (AtACBP6), Brassica napus (BnACBP) and Oryza sativa (OsACBP1, OsACBP2, OsACBP3), and they are capable of binding to different acyl-CoA esters and phospholipids. Here we characterize HaACBP6, a class I ACBP expressed in sunflower (Helianthus annuus) tissues, studying the specificity of its corresponding recombinant HaACBP6 protein towards various acyl-CoA esters and phospholipids in vitro, particularly using isothermal titration calorimetry and protein phospholipid binding assays. This protein binds with high affinity to de novo synthetized derivatives palmitoly-CoA, stearoyl-CoA and oleoyl-CoA (Kd 0.29, 0.14 and 0.15 μM respectively). On the contrary, it showed lower affinity towards linoleoyl-CoA (Kd 5.6 μM). Moreover, rHaACBP6 binds to different phosphatidylcholine species (dipalmitoyl-PC, dioleoyl-PC and dilinoleoyl-PC), yet it displays no affinity towards other phospholipids like lyso-PC, phosphatidic acid and lysophosphatidic acid derivatives. In the light of these results, the possible involvement of this protein in sunflower oil synthesis is considered.

  1. Identification of small molecule binding sites within proteins using phage display technology.

    Energy Technology Data Exchange (ETDEWEB)

    Rodi, D. J.; Agoston, G. E.; Manon, R.; Lapcevich, R.; Green, S. J.; Makowski, L.; Biosciences Division; EntreMed Inc.; Florida State Univ.

    2001-11-01

    Affinity selection of peptides displayed on phage particles was used as the basis for mapping molecular contacts between small molecule ligands and their protein targets. Analysis of the crystal structures of complexes between proteins and small molecule ligands revealed that virtually all ligands of molecular weight 300 Da or greater have a continuous binding epitope of 5 residues or more. This observation led to the development of a technique for binding site identification which involves statistical analysis of an affinity-selected set of peptides obtained by screening of libraries of random, phage-displayed peptides against small molecules attached to solid surfaces. A random sample of the selected peptides is sequenced and used as input for a similarity scanning program which calculates cumulative similarity scores along the length of the putative receptor. Regions of the protein sequence exhibiting the highest similarity with the selected peptides proved to have a high probability of being involved in ligand binding. This technique has been employed successfully to map the contact residues in multiple known targets of the anticancer drugs paclitaxel (Taxol), docetaxel (Taxotere) and 2-methoxyestradiol and the glycosaminoglycan hyaluronan, and to identify a novel paclitaxel receptor [1]. These data corroborate the observation that the binding properties of peptides displayed on the surface of phage particles can mimic the binding properties of peptides in naturally occurring proteins. It follows directly that structural context is relatively unimportant for determining the binding properties of these disordered peptides. This technique represents a novel, rapid, high resolution method for identifying potential ligand binding sites in the absence of three-dimensional information and has the potential to greatly enhance the speed of development of novel small molecule pharmaceuticals.

  2. Effect of blending HA-g-PLLA on xanthohumol-loaded PLGA fiber membrane.

    Science.gov (United States)

    Qiao, Tiankui; Jiang, Suchen; Song, Ping; Song, Xiaofeng; Liu, Qimin; Wang, Lijuan; Chen, Xuesi

    2016-10-01

    Electropsun poly (lactide-co-glycolide) (PLGA) fiber membrane loaded xanthohumol (XN) has been developed using a co-solvent system of chloroform and dimethylformamide. To enhance its biological functionality as bone tissue engineering scaffolds, 5wt% hydroxyapatite grafted poly (l-lactic acid) (HA-g-PLLA) is blended into the spinning solution. The purpose of the present work is to disclose the effect of blending HA-g-PLLA on the corresponding properties of the medicated fiber membrane including morphology, thermodynamics, wettability, drug release, mechanics as well as cytotoxicity. XN and HA-g-PLLA can be well blended with PLGA to make fibers. Blending HA-g-PLLA not only turns amorphous XN/PLGA fiber membrane into crystal structure, but also changes the membranous wettability. Various medicated membranes exhibit the sustained release profiles. Drug release rate of the ternary membrane with HA-g-PLLA is slower compared to the binary XN/PLGA, and for the ternary membrane, the drug release accelerates with increasing XN content. A model is proposed to account for the drug release process. Tensile testing shows that at 10% of XN, the comprehensive mechanics of the ternary is preferable to the binary. At the same time, these fiber membranes are no cytotoxicity.

  3. Trehalose improves cell proliferation and dehydration tolerance of human HaCaT cells

    Directory of Open Access Journals (Sweden)

    Lee Kyung Eun

    2015-01-01

    Full Text Available Trehalose is a disaccharide molecule that serves as a natural osmotic regulator in halophilic microorganisms and plants but not in mammals. We observed that human HaCaT cells supplied with trehalose improved cell proliferation and extended viability under dehydration. In HaCaT cells, in response to increasing concentrations of exogenous trehalose, the levels of heat shock protein (HSP 70 increased and matrix metalloproteinase (MMP 1 decreased. Proteome analysis of trehalose-treated HaCaT cells revealed remarkable increases in the levels of proteins involved in cell signaling and the cell cycle, including p21 activated kinase I, Sec I family domain protein and elongation factor G. Moreover, the proteins for cell stress resistance, tryptophan hydroxylase, serine/cysteine proteinase inhibitors and vitamin D receptors were also increased. In addition, the proteins responsible for the maintenance of the cytoskeleton and cellular structures including procollagen-lysine dioxygenase, vinculin and ezrin were increased. Proteomic data revealed that trehalose affected HaCaT cells by inducing the proteins involved in cell proliferation. These results suggest that trehalose improves the proliferation and dehydration tolerance of HaCaT cells by inducing proteins involved in cell growth and dehydration protection.

  4. Possible Detection of the Stellar Donor or Remnant for the Type Iax Supernova 2008ha

    CERN Document Server

    Foley, Ryan J; Jha, Saurabh W; Bildsten, Lars; Fong, Wen-fai; Narayan, Gautham; Rest, Armin; Stritzinger, Maximilian D

    2014-01-01

    Type Iax supernovae (SNe Iax) are thermonuclear explosions that are related to SNe Ia, but are physically distinct. The most important differences are that SNe Iax have significantly lower luminosity (1% - 50% that of typical SNe Ia), lower ejecta mass (~0.1 - 0.5 M_sun), and may leave a bound remnant. The most extreme SN Iax is SN 2008ha, which peaked at M_V = -14.2 mag, about 5 mag below that of typical SNe Ia. Here, we present Hubble Space Telescope (HST) images of UGC 12682, the host galaxy of SN 2008ha, taken 4.1 years after the peak brightness of SN 2008ha. In these deep, high-resolution images, we detect a source coincident (0.86 HST pixels; 0.043"; 1.1 sigma) with the position of SN 2008ha with M_F814W = -5.4 mag. We determine that this source is unlikely to be a chance coincidence, but that scenario cannot be completely ruled out. If this source is directly related to SN 2008ha, it is either the luminous bound remnant of the progenitor white dwarf or its companion star. The source is consistent with ...

  5. Construction of HA-1-DC Nucleic-acid Vaccine and Induction of Specific Cytotoxic T Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    WANG Yaya; ZHANG Donghua; HU Jinmei; LIU Wenli; ZHOU hongsheng; ZHANG Lu; LIU Dan; HUANG Zhenqian; TAN Huo

    2007-01-01

    An HA-1-DC nucleic-acid vaccine was constructed to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). DCs were generated from HSCT donors in vitro, and its immunologic activity was assayed by using flow cytometry and mixed lymphocytes reaction.HA-1 gene was electroporated into the cultured DCs to construct a DC nucleic-acid vaccine. After transfection for 48 h, the expression of HA-1 protein could be detected by using Western blot. The DCs were cultured with syngenic lymphocytes to induce specific cytotoxic T lymphocytes (CTLs).The cytoxicity of the CTLs was detected by LDH assay. The results showed that The DCs derived from peripheral blood monocytes (PBMCs) expressed the phenotype of DCs, and were effective in stimulating proliferation of the allogenic lymphocytes. After electroporating for 48-h, HA-1 protein was detected by using Western blot. The cytotoxity of inducing CTLs was higher than the control group. It was suggested that minor histocompatibility antigen HA-1 could be considered as a target of immunotherapy against leukemia after HSCT.

  6. Mechanical strength of [HA/Bioplastic/Sericin] composite part printed by bioprinter

    Energy Technology Data Exchange (ETDEWEB)

    Tontowi, Alva Edy, E-mail: alvaedytontowi@ugm.ac.id; Setiawan, Agris [Department of Mechanical and Industrial Engineering Faculty of Engineering Universitas Gadjah Mada (Indonesia)

    2016-06-17

    The aim of this research was to determine the effect of hydroxyapatite (HA) content in printed biocomposite to its mechanical strength. The biocomposite paste was prepared by composing HA, bioplastic and sericin with various ratios of [HA/Bioplastic]: 40/60, 50/50, 60,40 and 70/30. Sericin of 0.3% weight was added to the biocomposite. Mechanical test was conducted to observe tensile (ASTM D 638 type 4) and flexural strength (ASTM D 790). Both type of specimens were fabricated using 3D Printer. Printing process parameter (infill speed, print speed and layer height) were set up as 60 mm/s, 10 mm/s, 0.35 mm, respectively. Results showed that biocomposite with [HA/Biplastic]. weight ratio of 60/40(w/w) has an optimum tensile (3.89 ± 1.26 MPa) and flexural strength (2.51 ± 0.45 MPa). Scanning electron microscope observation indicated that microstructure of specimen was influenced by the percentage of the hydroxyapatite. There was no agglomeration of HA particle within the composite.

  7. Vibrio cholerae hemagglutinin(HA)/protease: an extracellular metalloprotease with multiple pathogenic activities

    Science.gov (United States)

    Benitez, Jorge A.; Silva, Anisia J.

    2016-01-01

    Vibrio cholerae of serogroup O1 and O139, the etiological agent of the diarrheal disease cholera, expresses the extracellular Zn-dependent metalloprotease hemagglutinin (HA)/protease also reported as vibriolysin. This enzyme is also produced by non-O1/O139 (non-cholera) strains that cause mild, sporadic illness (i.e. gastroenteritis, wound or ear infections). Orthologs of HA/protease are present in other members of the Vibrionaceae family pathogenic to humans and fish. HA/protease belongs to the M4 neutral peptidase family and displays significant amino acid sequence homology to Pseudomonas aeruginosa elastase (LasB) and Bacillus thermoproteolyticus thermolysin. It exhibits a broad range of potentially pathogenic activities in cell culture and animal models. These activities range from the covalent modification of other toxins, the degradation of the protective mucus barrier and disruption of intestinal tight junctions. Here we review (i) the structure and regulation of HA/protease expression, (ii) its interaction with other toxins and the intestinal mucosa and (iii) discuss the possible role(s) of HA/protease in the pathogenesis of cholera. PMID:26952544

  8. New Coll–HA/BT composite materials for hard tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zanfir, Andrei Vlad [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Material Science, “Politehnica” University of Bucharest, 1-7 Gh. Polizu Street, RO-011061 Bucharest (Romania); Voicu, Georgeta, E-mail: getav2001@yahoo.co.uk [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Material Science, “Politehnica” University of Bucharest, 1-7 Gh. Polizu Street, RO-011061 Bucharest (Romania); Busuioc, Cristina; Jinga, Sorin Ion [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Material Science, “Politehnica” University of Bucharest, 1-7 Gh. Polizu Street, RO-011061 Bucharest (Romania); Albu, Madalina Georgiana [Department of Collagen, Branch of Leather and Footwear Research, National Institute of Research and Development for Textile and Leather, 93 I. Minulescu Street, RO-031215 Bucharest (Romania); Iordache, Florin [Department of Fetal and Adult Stem Cell Therapy, “Nicolae Simionescu” Institute of Cellular Biology and Pathology of Romanian Academy, 8 B.P. Hasdeu Street, RO-050568 Bucharest (Romania)

    2016-05-01

    The integration of ceramic powders in composite materials for bone scaffolds can improve the osseointegration process. This work was aimed to the synthesis and characterization of new collagen–hydroxyapatite/barium titanate (Coll–HA/BT) composite materials starting from barium titanate (BT) nanopowder, hydroxyapatite (HA) nanopowder and collagen (Coll) gel. BT nanopowder was produced by combining two wet-chemical approaches, sol–gel and hydrothermal methods. The resulting materials were characterized in terms of phase composition and microstructure by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. Moreover, the biocompatibility and bioactivity of the composite materials were assessed by in vitro tests. The synthesized BT particles exhibit an average size of around 35 nm and a spherical morphology, with a pseudo-cubic or tetragonal symmetry. The diffraction spectra of Coll–HA and Coll–HA/BT composite materials indicate a pronounced interaction between Col and the mineral phases, meaning a good mineralization of Col fibres. As well, the in vitro tests highlight excellent osteoinductive properties for all biological samples, especially for Coll–HA/BT composite materials, fact that can be attributed to the ferromagnetic properties of BT. - Highlights: • Collagen–hydroxyapatite/barium titanate composite materials were synthesized. • Barium titanate was produced by combining the sol–gel and hydrothermal methods. • The in vitro tests highlight excellent osteoinductive properties for all samples.

  9. HaNDL Syndrome Presenting During Pregnancy: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Yüksel Kaplan

    2014-09-01

    Full Text Available Headache associated with neurological deficits and cerebrospinal fluid lymphocytosis (HaNDL is a self-limited syndrome characterized by sudden-onset headache with a temporary neurological deficit and cerebrospinal fluid (CSF lymphocytosis. We aimed to disscus a case of HaNDL syndrome presenting during pregnancy with relevant literature. A 20-year-old female presented with a 5-day history of severe, bilateral throbbing headache accompanied by nausea, vomiting, and phonophobia. Approximately 2 days after the pain developed, she became acutely confused for less than 90 minutes. 2 days after this episode, she experienced again confusional state and left hemiparesis. There were no symptoms consistent with meningoencephalitis. She was pregnant and at 11 weeks gestation. A neurologic examination showed confusional state, bilateral papilledema, and mild left hemiparesis. The neuroradiological examination was normal. The cerebrospinal fluid revealed lymphocytic pleocytosis, mildly elevated protein, and increased opening pressure. She recovered completely after 8 days. The precise etiology of HaNDL is unknown, although an inflammatory or infectious origin and autoimmune factors have been proposed. Moreover, the risk factors and medical conditions associated with HaNDL are unknown. It is obviously difficult to determine whether the pregnancy was coincidental or associated in this case. We believe that comprehensive studies are needed to clarify the risk factors and medical conditions associated with HaNDL.

  10. HaVec: An Efficient de Bruijn Graph Construction Algorithm for Genome Assembly

    Directory of Open Access Journals (Sweden)

    Md Mahfuzer Rahman

    2017-01-01

    Full Text Available Background. The rapid advancement of sequencing technologies has made it possible to regularly produce millions of high-quality reads from the DNA samples in the sequencing laboratories. To this end, the de Bruijn graph is a popular data structure in the genome assembly literature for efficient representation and processing of data. Due to the number of nodes in a de Bruijn graph, the main barrier here is the memory and runtime. Therefore, this area has received significant attention in contemporary literature. Results. In this paper, we present an approach called HaVec that attempts to achieve a balance between the memory consumption and the running time. HaVec uses a hash table along with an auxiliary vector data structure to store the de Bruijn graph thereby improving the total memory usage and the running time. A critical and noteworthy feature of HaVec is that it exhibits no false positive error. Conclusions. In general, the graph construction procedure takes the major share of the time involved in an assembly process. HaVec can be seen as a significant advancement in this aspect. We anticipate that HaVec will be extremely useful in the de Bruijn graph-based genome assembly.

  11. Study on biocompatibility of PDLLA/HA/DBM with co-cultured human osteoblasts in vitro

    Institute of Scientific and Technical Information of China (English)

    郭乔楠; 赵建华; 卢佳友

    2003-01-01

    Objective: To evaluate the osteocompatibility of D, L-polylactic/hydroxyapatite/decalcifying bone matrix (PDLLA/HA/DBM), and compare with PDLLA and DBM. Methods: Human primary osteoblasts isolated from the femoral head of patients were inoculated onto PDLLA/HA/DBM, PLA and DBM respectively. The proliferation rate and collagen Ⅰ expression were detected. The interface between biomaterial and osteoblasts was investigated with phase contrast microscopy and electron scanning microscopy. Results: Best proliferation rate was observed with the PDLLA/HA/DBM and followed by DBM and PLA, suggesting that PDLLA/HA/DBM satisfying most requirements for the cultivation of human osteoblasts. Scanning electron microscopy showed the morphology of osteoblasts was correlated with the proliferation data. The cells, well spread and flattened, were attached closely on the surface of biomaterial with an arched structure and had normal morphology. The extracellular collagenous matrixs covered the surface of biomaterial and packed the granules of biomaterial. Conclusion: PDLLA/HA/DBM can form osteointerface early and have a good biocompability.

  12. New Coll-HA/BT composite materials for hard tissue engineering.

    Science.gov (United States)

    Zanfir, Andrei Vlad; Voicu, Georgeta; Busuioc, Cristina; Jinga, Sorin Ion; Albu, Madalina Georgiana; Iordache, Florin

    2016-05-01

    The integration of ceramic powders in composite materials for bone scaffolds can improve the osseointegration process. This work was aimed to the synthesis and characterization of new collagen-hydroxyapatite/barium titanate (Coll-HA/BT) composite materials starting from barium titanate (BT) nanopowder, hydroxyapatite (HA) nanopowder and collagen (Coll) gel. BT nanopowder was produced by combining two wet-chemical approaches, sol-gel and hydrothermal methods. The resulting materials were characterized in terms of phase composition and microstructure by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. Moreover, the biocompatibility and bioactivity of the composite materials were assessed by in vitro tests. The synthesized BT particles exhibit an average size of around 35 nm and a spherical morphology, with a pseudo-cubic or tetragonal symmetry. The diffraction spectra of Coll-HA and Coll-HA/BT composite materials indicate a pronounced interaction between Col and the mineral phases, meaning a good mineralization of Col fibres. As well, the in vitro tests highlight excellent osteoinductive properties for all biological samples, especially for Coll-HA/BT composite materials, fact that can be attributed to the ferromagnetic properties of BT.

  13. Improving post-transfer survival of bovine embryos produced in vitro: actions of insulin-like growth factor-1, colony stimulating factor-2 and hyaluronan.

    Science.gov (United States)

    Block, J; Hansen, P J; Loureiro, B; Bonilla, L

    2011-12-01

    Technologies for in vitro embryo production have the potential to enhance the efficiency of cattle production systems. However, utilization of in vitro-produced embryos for transfer remains limited throughout much of the world. Despite improvements over the past two decades, problems associated with the production of bovine embryos in vitro still exist which limit the widespread commercial application of this technology. In particular, bovine embryos produced in vitro have a reduced capacity to establish and maintain pregnancy as compared with their in vivo-derived counterparts. Embryo competence for survival following transfer is improved by in vivo culture in the sheep oviduct, thus indicating that standard embryo culture conditions are sub-optimal. Therefore, one strategy to improve post-transfer survival is to modify embryo culture media to more closely mimic the in vivo microenvironment. The maternal environment in which the bovine embryo develops in vivo contains various growth factors, cytokines, hormones, and other regulatory molecules. In addition to affecting bovine embryo development in vitro, recent research indicates that embryo competence for survival following transfer can also be improved when such molecules are added to embryo culture medium. Among the specific molecules that can increase post-transfer embryo survival are insulin-like growth factor-1 (IGF-1), colony stimulating factor-2 (CSF-2) and hyaluronan. This paper will review the effects IGF-1, CSF-2 and hyaluronan on post-culture embryo viability and discuss the potential mechanisms through which each of these molecules improves post-transfer survival. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Hyaluronic acid binding, endocytosis and degradation by sinusoidal liver endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    McGary, C.T.

    1988-01-01

    The binding, endocytosis, and degradation of {sup 125}I-hyaluronic acid ({sup 125}I-HA) by liver endothelial cells (LEC) was studied under several conditions. The dissociation of receptor-bound {sup 125}I-HA was rapid, with a half time of {approx}31 min and a K{sub off} of 6.3 {times} 10{sup {minus}4}/sec. A large reversible increase in {sup 125}I-HA binding to LEC at pH 5.0 was due to an increase in the observed affinity of the binding interaction. Pronase digestion suggested the protein nature of the receptor and the intracellular location of the digitonin exposed binding activity. Binding and endocytosis occur in the presence of 10 mM EGTA indicating that divalent cations are not required for receptor function. To study the degradation of {sup 125}I-HA by LEC, a cetylpyridinium chloride (CPC) precipitation assay was characterized. The minimum HA length required for precipitation was elucidated. The fate of the LEC HA receptor after endocytosis was examined.

  15. Synthesis and Kinetics of a Novel Mimic with Glutathione Peroxidase Activity-Tellurium-containing Hyaluronic Acid (TeHA)

    Institute of Scientific and Technical Information of China (English)

    Zhi Bo CHEN; Lan Ying LIU; Bo Xun ZHANG; Zhong Xiu HUANG; Qing Lin PENG; Jia CHEN; Yu WANG; Jian Guo ZHANG; Guang Zhi JIANG; Wen Shu LI

    2006-01-01

    A novel mimic was synthesized by modifying hyaluronic acid (HA) with tellurium,whose function is similar to that of glutathione peroxidase (GPX). The structure of TeHA was characterized by means of IR and NMR, the target-Te was located at -CH2OH of the N-acetyl-D-glucosamine of HA. The H2O2 reducing activity of TeHA, by glutathione (GSH), was 163.6U/μmol according to Wilson's method. In contrast to other mimics, TeHA displayed the highest activity. Moreover, TeHA accepted many hydroperoxides as its substrates, such as H2O2, cumenyl hydroperoxide (CuOOH) and tert-butyl hydroperoxide (t-BuOOH), and CuOOH was the optimal substrate of TeHA. A ping-pong mechanism was observed in the steady-state kinetic studies of the reactions catalyzed by TeHA.

  16. Induction of CYP1A1 and CYP2E1 in rat liver by histamine: binding and kinetic studies.

    Science.gov (United States)

    Dávila-Borja, Víctor M; Belmont, Javier A; Espinosa, J Javier; Moreno-Sánchez, Rafael; Albores, Arnulfo; Montero, Regina D

    2007-10-01

    Histamine (HA) may bind to cytochrome P450 (CYP450) in rat liver microsomes. The CYP450-HA complex seems to regulate some cellular processes such as proliferation. In the present work, it is shown that HA increases the activity and protein level of CYP1A1 and CYP2E1, in vivo. CYP1A1 is associated with polycyclic aromatic hydrocarbon-mediated carcinogenesis and CYP2E1 with liver damage by oxidative stress. Studies of enzyme kinetics and binding with rat liver microsomes and supersomes were carried out to determine whether HA is a substrate of CYP1A1 and/or CYP2E1. The lack of NADPH oxidation in the presence of HA showed that it is not a substrate for CYP1A1. Activity measurements using the O-dealkylation of ethoxyresorufin indicated that HA is a mixed-type inhibitor of CYP1A1 in both microsomes and supersomes. On the other hand, HA induced a significant NADPH oxidation catalyzed by CYP2E1 supersomes, strongly suggesting that HA is a substrate for this isoform. Furthermore, HA is consumed in the presence of CYP2E1-induced microsomes and supersomes, as determined by o-phtalaldehyde complexes with HA by HPLC. The present findings may contribute to understand better the physiological function of CYP450 in relation with inflammation and other physiological processes in which HA may have a relevant role.

  17. Mechanical, thermal, rheological and morphological behaviour of irradiated PP/HA composites

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, C. [Universidad de Oriente, Nucleo de Anzoategui, Escuela de Ingenieria y Ciencias Aplicadas, Depto de Ingenieria Quimica, Puerto la Cruz (Venezuela); Albano, C. [Centro de Quimica, Laboratorio de Polimeros, Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas 1020A (Venezuela) and Universidad Central de Venezuela, Facultad de Ingenieria, Escuela de Ingenieria Quimica, Caracas 1041A (Venezuela)]. E-mail: calbano@ivic.ve; Karam, A. [Centro de Quimica, Laboratorio de Polimeros, Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas 1020A (Venezuela)]. E-mail: akaram@quimica.ivic.ve; Dominguez, N. [Centro de Quimica, Laboratorio de Polimeros, Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas 1020A (Venezuela); Sanchez, Y. [Centro de Quimica, Laboratorio de Polimeros, Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas 1020A (Venezuela); Gonzalez, G. [Centro Tecnologico, Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas 1020A (Venezuela)

    2005-07-01

    Hydroxyapatite (HA) reinforced polypropylene (PP) composites are being developed as bone graft materials. In this research, the effect of {gamma} irradiation on mechanical, rheological, thermal and morphological behaviour of PP-HA composites was studied. The melt flow index of polymer increased markedly when it was exposed to radiation. This is indicative of chain scission reaction as the predominant process. During the tensile testing, the composites exhibited brittle behaviour, showing no fluency point. Elongation at break showed a tendency to decrease with the increase in radiation dose while stress at break did not show significant variation with radiation dose. High HA content (>20%) and radiation dose (25 kGy) had significant influence on thermal stability.

  18. Confusional State in HaNDL Syndrome: Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Sarah Nelson

    2013-01-01

    Full Text Available The syndrome of transient headache and neurologic deficits with cerebrospinal fluid lymphocytosis (HaNDL syndrome is a self-limited condition. Confusional states are uncommonly reported as a clinical manifestation of this syndrome. Here, I report a 76-year-old female who presented with headache, confusion, and agitation with a mild CSF lymphocytosis. Other workup to determine the cause of her altered mental status was otherwise negative. The literature available in the English language on HaNDL syndrome is reviewed, including its history, pathophysiology, possible associations with migraine and stroke, and previously reported cases of confusional states in this syndrome. While HaNDL syndrome has been a described entity since the 1980s, its pathophysiology has yet to be clearly defined.

  19. Effect of Heat-treatment Temperature on HA-coated Titanium Materials

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Homogeneous HA coating materials were prepared on porous titanium by the low-temperature combustion synthesis. It was found that the mechanical properties of the specimen depend on the coating process and the heat treatment, and the bending strength would be reduced during the coating process but could be improved by heat treatment. The effects of the temperature during heat-treatment on the phase composition and microstructure of the as-prepared coating, and the bending strength of the specimen were investigated by XRD and SEM.The experimental results show that in the coating process, slight oxidation of the substrate may give rise to a drop in bending strength; however, it could be increased by the reaction of HA and TiO2, and the sintering of the coating during heat treatment. The HA particles in the coating, with very fine sized particles, were pretty active and would decompose at 800 ℃ .

  20. HA-BMP复合人工听小骨临床应用初步报告%A preliminary clinical application report of HA-BMP artificial ossicle

    Institute of Scientific and Technical Information of China (English)

    宋为明; 谢华顺; 张龙城; 李学佩

    2004-01-01

    目的对应用HA-BMP复合人工听小骨的听骨链重建术后听力效果进行评价,寻找一种生物相容性好并且能被机体骨组织替代的听骨链重建材料.多孔羟基磷灰石(Hydroxyapatites,HA)人工骨具有良好的生物相容性及骨传导功能,无毒、无免疫反应,因此在临床上有很大的应用前景.骨形态发生蛋白(Bone Morphogenetic Protein,BMP)是一种存在于骨组织中的酸性糖蛋白,其主要生物学作用是诱导未分化的间充质细胞分化形成软骨与骨.方法用骨形态发生蛋白(BMP)复合多孔羟基磷灰石(HA)制成复合型人工听小骨(BMP-HA),在动物实验成功的基础上,试用于临床,共计14例,其中部分听骨链赝复物(partial ossicular replacement prosthesis PORP)9例,全听骨链赝复物(total ossicular replacement prosthesis,TORP)5例.结果术后均获一期干耳,随访至少3年,无脱出现象,术后听力稳定,平均气导较术前提高29.5dB.结论BMP-HA人工听小骨是一种具有较强骨诱导能力、生物相容性良好的人工听小骨,作为中耳传音结构重建材料,优于单纯羟基磷灰石人工听小骨.

  1. New insight to structure-function relationship of GalNAc mediated primary interaction between insecticidal Cry1Ac toxin and HaALP receptor of Helicoverpa armigera.

    Directory of Open Access Journals (Sweden)

    Anindita Sengupta

    Full Text Available Over the last few decades Cry1Ac toxin has been widely used in controlling the insect attack due to its high specificity towards target insects. The pore-forming toxin undergoes a complex mechanism in the insect midgut involving sequential interaction with specific glycosylated receptors in which terminal GalNAc molecule plays a vital role. Recent studies on Cry toxins interactions with specific receptors revealed the importance of several amino acid residues in domain III of Cry1Ac, namely Q509, N510, R511, Y513 and W545, serve as potential binding sites that surround the putative GalNAc binding pocket and mediate the toxin-receptor interaction. In the present study, alanine substitution mutations were generated in the Cry1Ac domain III region and functional significance of those key residues was monitored by insect bioassay on Helicoverpa armigera larvae. In addition, ligand blot analysis and SPR binding assay was performed to monitor the binding characteristics of Cry1Ac wild type and mutant toxins towards HaALP receptor isolated from Helicoverpa armigera. Mutagenesis data revealed that, alanine substitutions in R511, Y513 and W545 substantially impacted the relative affinity towards HaALP receptor and toxicity toward target insect. Furthermore, in silico study of GalNAc-mediated interaction also confirmed the important roles of these residues. This structural analysis will provide a detail insight for evaluating and engineering new generation Cry toxins to address the problem of change in insect behavioral patterns.

  2. Re-establishment of the IMS Hydroacoustic Station HA04, Crozet Islands, France.

    Science.gov (United States)

    Haralabus, Georgios; Stanley, Jerry; Zampolli, Mario; Grenard, Patrick; Nielsen, Peter; Le Bras, Ronan; Brown, David; Bittner, Paulina; Wang, Haijun; Gore, Jane; Amir, Menachem; Bereza, Slava

    2017-04-01

    The incorporation of the hydroacoustic station HA04, Crozet Islands, France, into the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO) is a 17 year saga that had a happy ending on 29 December 2016. On that day, following a major engineering and logistical undertaking, the station was successfully installed. While still in its initial testing phase, HA04 sends continuously quality data at the International Data Centre (IDC), pending official certification and promotion to mainstream operational status. Similarly to most other cabled hydroacoustic stations in the IMS, HA04 is comprised of two triplets of moored hydrophones deployed on both sides of Possession Island (Crozet Islands) sending uninterrupted data to a shore facility via submarine fiber optic cables. The designed frequency pass-band is 1 - 100 Hz. Data are relayed to Vienna via a shore based satellite link in real time. According to CTBTO's standard requirements, the design life of HA04 is at least 20 years, maintenance-free for the underwater system. An outline of the main phases of this project, highlights from the installation operations and examples of received hydroacoustic signals associated with recent underwater seismic activity in the Indian Ocean as well as vocalizations from marine mammals acquired by the new HA04 are presented here. HA04 is scheduled to be fully integrated into the operational platform of IDC in the next six months, which will enable registered researchers to access archived monitoring data and processing software, or via the National Data Centres (NDCs).

  3. Tracheal reconstruction using chondrocytes seeded on a poly(L-lactic-co-glycolic acid)-fibrin/hyaluronan.

    Science.gov (United States)

    Hong, Hyun Jun; Chang, Jae Won; Park, Ju-Kyeong; Choi, Jae Won; Kim, Yoo Suk; Shin, Yoo Seob; Kim, Chul-Ho; Choi, Eun Chang

    2014-11-01

    Reconstruction of trachea is still a clinical dilemma. Tissue engineering is a recent and promising concept to resolve this problem. This study evaluated the feasibility of allogeneic chondrocytes cultured with fibrin/hyaluronic acid (HA) hydrogel and degradable porous poly(L-lactic-co-glycolic acid) (PLGA) scaffold for partial tracheal reconstruction. Chondrocytes from rabbit articular cartilage were expanded and cultured with fibrin/HA hydrogel and injected into a 5 × 10 mm-sized, curved patch-shape PLGA scaffold. After 4 weeks in vitro culture, the scaffold was implanted on a tracheal defect in eight rabbits. Six and 10 weeks postoperatively, the implanted sites were evaluated by bronchoscope and radiologic and histologic analyses. Ciliary beat frequency (CBF) of regenerated epithelium was also evaluated. None of the eight rabbits showed any sign of respiratory distress. Bronchoscopic examination did not reveal stenosis of the reconstructed trachea and the defects were completely recovered with respiratory epithelium. Computed tomography scan showed good luminal contour of trachea. Histologic data showed that the implanted chondrocytes successfully formed neocartilage with minimal granulation tissue. CBF of regenerated epithelium was similar to that of normal epithelium. Partial tracheal defect was successfully reconstructed anatomically and functionally using allogeneic chondrocytes cultured with PLGA-fibrin/HA composite scaffold.

  4. IMPACT OF DYNAMICAL HYDRATION SHELL AROUND HA PROTEIN ON NONLINEAR CONCENTRATION DEPENDENT T-RAYS ABSORPTION

    Directory of Open Access Journals (Sweden)

    YIWEN SUN

    2013-10-01

    Full Text Available T-rays is sensitive to covalently cross-linked proteins and can be used to probe unique dynamic properties of water surrounding a protein. In this paper, we demonstrate the unique absorption properties of the dynamic hydration shells determined by hemagglutinin (HA protein in terahertz frequency. We study the changes arising from different concentrations in detail and show that nonlinear absorption coefficient is induced by the dynamic hydration water. The binary and ternary component model were used to interpret the nonlinearity absorption behaviors and predict the thickness of the hydration shells around the HA protein in aqueous phase.

  5. A peptide-binding assay for the disease-associated HLA-DQ8 molecule

    DEFF Research Database (Denmark)

    Straumfors, A; Johansen, B H; Vartdal, F;

    1998-01-01

    . The Ha 255-271(Y) peptide bound to DQ8 in a pH-dependent fashion showing optimal binding around pH 5. The association kinetics were relatively slow and the resulting complexes were heat labile. The specificity of peptide binding to DQ8 was investigated in competitive inhibition experiments with a panel...

  6. Securing Binding Updates in Routing Optimizaton of Mobile IPv6

    Directory of Open Access Journals (Sweden)

    S. Rajkumar

    2012-06-01

    Full Text Available Mobile IPv6 (mipv6 is an internet protocol that allows mobile nodes to have continuous network connectivity to the internet without changing their ip addresses while moving to other networks. The packets sent from Correspondent Node (CN to a Mobile Node (MN go first through the mobile node’s Home Agent (HA. Then the HA tunnels them to the MN’s foreign network. This process of delivering the packets to CN is called triangle routing. Triangle routing problem appears when the indirect path between CN and MN through the HA is longer than the direct path. To overcome triangle routing, Route Optimization (RO method is added in mobile Pv6. In route optimization, when MN changes its location, it sends a Binding Update (BU to CN informing its CoA. To secure these Binding Updates, we present a new protocol called “Certificate Based Inquisition Approach” for securing Binding Updates in RO. Performance analysis of this shows that it is computationally efficient than RR protocol and is not susceptible to any security attacks. To show the effectiveness of the proposed technique, it is compared with the state of art of other RO protocols. Simulation results presented in this study are based on the ns2 mobility software on linux platform. The simulations results show that our proposed technique achieves better performance than the Return Routability (RR, Certificate Based Binding Update protocol (CBU, Hierarchical Certificate Based Binding Update protocol (HCBU.

  7. The Tissue Implant Response Surrounding Subcutaneous TCP, HA, And ALCAP Bioceramics.

    Science.gov (United States)

    Butler, K R; Benghuzzi, Hamed; Tucci, Michelle; Puckett, A D

    2015-01-01

    The objective of this investigation was to quantify and further elucidate the tissue-implant response in the fibrous tissue surrounding tricalcium phosphate (TCP), hydroxyapatite (HA), and aluminum calcium phosphate (ALCAP) implants when implanted subcutaneously. Sixteen animals in four experimental groups (n = 4/group) were implanted with one implant each: Group I (control, TCP), Group II (HA), and Group III (ALCAP). At 90 days post-implantation, the fibrous tissue surrounding the implants was harvested. Sections of stained fibrous tissue were evaluated for the presence of macrophages, fibrocytes, neutrophils, vascularity and thickness for all three groups using semi-automated quantitative methods. The analysis indicated Group III demonstrated a significantly higher number of neutrophils but fewer macrophages and blood vessels per high power field and had a substantially thinner fibrous tissue capsule thickness compared to Groups I and II (alpha=0.05). Group II elicited a greater response of fibroblasts compared to Groups I and III suggesting HA may provide a slightly higher degree of stability to the implant. In total, these findings suggest both TCP and HA behave similarly in vivo when compared to ALCAP and may be better choices for subcutaneous soft-tissue application compared to ALCAP.

  8. Study of the gamma irradiation effects on the PMMA/HA and PMMA/SW

    Science.gov (United States)

    Silva, P.; Albano, C.; Perera, R.; Domínguez, N.

    2010-03-01

    The behavior of the poly(methyl methacrylate) (PMMA) under the action of gamma radiation has been sufficiently studied. In this work, we present results from melt flow index (MFI), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) of PMMA composites with hydroxyapatite (HA) and seaweed residues (SW) irradiated with gamma rays at 1.08 kGy/h. Composites of PMMA/HA and PMMA/SW with 10%, 20% and 30% of the filler were prepared. The results show an increase in the MFI values with the integral dose of radiation, being consistent with chain-scission reactions. No EPR signal was observed in pure PMMA, while in the composites, the typical EPR signal of the PMMA radicals was observed, which increased with the amount of HA or SW. When comparing the relative intensities of the EPR signals for both types of composites, a slight increase in the concentration of free radicals generated in the sample with SW respect to that of PMMA/HA composite was obtained. A decay of the total free radical concentration was observed as time elapsed.

  9. Poola filmid ja näitus Püha Katariina kirikus

    Index Scriptorium Estoniae

    2006-01-01

    ha Katariina kirikus Tallinnas on ülehomseni üleval näitus poola filmirežissööri Krzysztof Kieslowski noorpõlves tehtud fotodest. Näidatakse tema filmitsüklit "Dekaloog", filme "Lodzi linnast" (1969) ja "Esimene armastus" (1974)

  10. The performance of dental pulp stem cells on nanofibrous PCL/gelatin/nHA scaffolds.

    NARCIS (Netherlands)

    Yang, X.; Yang, F.; Walboomers, X.F.; Bian, Z.; Fan, M.; Jansen, J.A.

    2010-01-01

    The aim of current study is to investigate the in vitro and in vivo behavior of dental pulp stem cells (DPSCs) seeded on electrospun poly(epsilon-caprolactone) (PCL)/gelatin scaffolds with or without the addition of nano-hydroxyapatite (nHA). For the in vitro evaluation, DNA content, alkaline phosph

  11. Molecular evolution of two lineages related to influenza B virus based on HA1 gen

    Institute of Scientific and Technical Information of China (English)

    金青青

    2013-01-01

    Objective To study the evolutionary characteristics and rules of two lineages on influenza B virus.Methods A total of 126 HA1 sequences of strains isolated during 1940 to 201 2were downloaded from the GenBank.Time of the most recent common

  12. Using accessibility indicators to investigate urban growth and motorcycles use in Ha Noi City, Vietnam

    NARCIS (Netherlands)

    Quang, N.N.; Quang, Ngoc Quang; Zuidgeest, M.H.P.; van den Bosch, F.H.M.; Sliuzas, R.V.; van Maarseveen, M.F.A.M.

    2013-01-01

    To investigate the impact of urban growth on motorcycles use in Ha Noi City, Vietnam, this paper maps and analysis three types of accessibility indicators. The results show that the levels of accessibility to jobs by public transport are very poor as compared to motorcycle and car, explaining the

  13. Anisotropic multicompartment micro- and nano-capsules produced via embedding into biocompatible PLL/HA films.

    Science.gov (United States)

    Delcea, Mihaela; Madaboosi, Narayanan; Yashchenok, Alexey M; Subedi, Prabal; Volodkin, Dmitry V; De Geest, Bruno G; Möhwald, Helmuth; Skirtach, André G

    2011-02-21

    We present a novel strategy to fabricate anisotropic multicompartment Janus capsules by embedding larger containers into a soft poly-L-lysine/hyaluronic acid (PLL/HA) polymeric film, followed by adsorption of smaller containers on top of their unmasked surface. This research is also attractive for developing substrates for cell cultures.

  14. The kinematics and binary-induced shaping of PN HaTr 4

    CERN Document Server

    Tyndall, Amy; Lloyd, Myfanwy

    2011-01-01

    We present the first detailed spatio-kinematical analysis of the planetary nebula HaTr 4, one of few known to contain a post-Common-Envelope central star system. Based on high spatial and spectral resolution spectroscopy of the [OIII]5004.84 angstrom nebular emission line, in combination with deep, narrow-band imagery, a spatio-kinematical model was developed in order to accurately determine the three-dimensional morphology and orientation of HaTr 4. The nebula is found to display an extended ovoid morphology with an equatorial enhancement consistent with a toroidal waist - a feature believed to be typical of central star binarity. The nebular inclination is found to be in good agreement with that determined for the binary plane, providing strong evidence that shaping and evolution of HaTr 4 has been influenced by its central binary system - making HaTr 4 one of only 5 planetary nebulae to have had this observationally proven.

  15. MICROSPOROGENESIS IN 3 TETRAPLOID SOMATIC HYBRIDS OF POTATO AND THEIR DI(HA)PLOID FUSION PARTNERS

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA; MATTHEIJ, WM

    1992-01-01

    The microsporogenesis of three somatic hybrids of potato, i.e. one tetraploid Solanum tuberosum (+) S. phureja, one tetraploid and one hypertetraploid S. tuberosum (+) desynaptic mutant, has been examined and compared with the microsporogenesis of the di(ha)ploid fusion partners. The somatic hybrids

  16. Influenza A HA's conserved epitopes and broadly neutralizing antibodies: a prediction method.

    Science.gov (United States)

    Ren, Jing; Ellis, John; Li, Jinyan

    2014-10-01

    A conserved epitope is an epitope retained by multiple strains of influenza as the key target of a broadly neutralizing antibody. Identification of conserved epitopes is of strong interest to help design broad-spectrum vaccines against influenza. Conservation score measures the evolutionary conservation of an amino acid position in a protein based on the phylogenetic relationships observed amongst homologous sequences. Here, Average Amino Acid Conservation Score (AAACS) is proposed as a method to identify HA's conserved epitopes. Our analysis shows that there is a clear distinction between conserved epitopes and nonconserved epitopes in terms of AAACS. This method also provides an excellent classification performance on an independent dataset. In contrast, alignment-based comparison methods do not work well for this problem, because conserved epitopes to the same broadly neutralizing antibody are usually not identical or similar. Location-based methods are not successful either, because conserved epitopes are located at both the less-conserved globular head (HA1) and the more-conserved stem (HA2). As a case study, two conserved epitopes on HA are predicted for the influenza A virus H7N9: One should match the broadly neutralizing antibodies CR9114 or FI6v3, while the other is new and requires validation by wet-lab experiments.

  17. Characterization, mechanical properties and corrosion resistance of biocompatible Zn-HA/TiO2 nanocomposite coatings.

    Science.gov (United States)

    Mirak, Mohammad; Alizadeh, Morteza; Ghaffari, Mohammad; Ashtiani, Mohammad Najafi

    2016-09-01

    Biocompatible Zinc-hydroxyapatite-titania and Zinc-hydroxyapatite nanocomposite coatings have been prepared by electrodeposition on NiTi shape memory alloy. Structures of coatings were characterized using X-ray diffraction (XRD). It was found that addition of TiO2 particles cause to reduction of crystallite size of coating. Scanning Electronic Microscope (SEM) observation showed that the Zn-HA/TiO2 coating consists of plate-like regions which can express that this plate-like structure can facilitate bone growth. X-ray photoelectron microscope (XPS) was performed to investigation of chemical state of composite coating and showed that Zinc matrix was bonded to oxygen. high-resolution transmission electron microscope (HRTEM) result illustrated the crystalline structure of nanocomposite coating. Mechanical behavior of coating was evaluated using microhardness and ball on disk wear test. The TiO2 incorporated composite coatings exhibited the better hardness and anti-wear performance than the Zn-HA coatings. Polarization measurements have been used to evaluate the electrochemical coatings performance. The Zn-HA/TiO2 composite coatings showed the highest corrosion resistance compared with Zn-HA and bare NiTi. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Data of evolutionary structure change: 1B9HA-2FNIA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1B9HA-2FNIA 1B9H 2FNI A A -KAPEFPAWPQYDDAERNGLVRALEQGQWWRMGGDEVNS...------------QLFNTAPLKSAEDFYHAEISLPCHA-NLNLESVQNIAHSVLKTFESFKI - HHHHHHHHHHHH HHHHHHHHHHH EEEEE ... 2FNI A 2FNIA 2FNI A 2FNIA MLKKDFFEGEV 2FNI A 2FNIA KQLTQ--GKR

  19. ¿Qué ha pasado con el agua en el nuevo estado plurinacional de Bolivia?

    Directory of Open Access Journals (Sweden)

    Nataly Viviana VARGAS GAMBOA

    2015-04-01

    Full Text Available La protección del derecho al agua ha sido el principal objetivo de los más emblemáticos movimientos sociales de los últimos tiempos en Bolivia. Su continua violación ha ocasionado un quiebre en la dinámica social, propiciando un con?icto que ha derivado en el empoderamiento de las clases populares frente a los abusos del gobierno. Dichos movimientos sociales se han movilizado no solo por el cese de la violación puntual del derecho al agua, sino que conscientes de su poder han ido más allá y engendraron el germen de la Asamblea Constituyente, buscando reformar completamente el texto constitucional e incluir en él un amplio espectro de protección para el derecho al agua. Ello ha derivado en el replanteamiento de una serie de políticas por parte del sector público para la realización de este derecho, motivando una fuerte inversión y una gran protección jurisdiccional. Sin embargo, los con?ictos de acceso y protección aún persisten, siendo una gran fuente de preocupación por parte de la población.

  20. 24 CFR 964.135 - Resident involvement in HA management operations.

    Science.gov (United States)

    2010-04-01

    ... management operations. 964.135 Section 964.135 Housing and Urban Development Regulations Relating to Housing... Tenant Participation § 964.135 Resident involvement in HA management operations. Residents shall be... responsibility for management operations, it shall ensure strong resident participation in all issues and...

  1. Áreas metropolitanas:¿qué ha cambiado?: La experiencia de la Caracas Metropolitana

    Directory of Open Access Journals (Sweden)

    Sonia Barrios

    2001-05-01

    Full Text Available La nueva economía de la información y del conocimiento ha tenido tres decisivas implicaciones de orden territorial. Primero, ha acelerado el proceso de aglomeración urbana a escala planetaria. Segundo, ha provocado fuertes alteraciones en las redes urbanas de ámbito mundial, regional y nacional. Y tercero, ha impulsado la reestructuración interna de las áreas metropolitanas que se habían conformado durante la era industrial. Todo parece anticipar, por lo tanto, polarizaciones y fragmentaciones territoriales todavía más acentuadas que las conocidas en un pasado cercano. Tomando como referencia el caso de Caracas, se trata de averiguar en qué medida el desarrollo reciente de esta metrópoli sigue las grandes tendencias territoriales antes anotadas; y qué esfuerzos se están haciendo para ajustar sus instancias locales a las nuevas realidades urbanas. Como un recurso adicional, en distintos momentos se establecen comparaciones con Barcelona (España, considerada un ejemplo emblemático de las metrópolis de la era de la información

  2. Euroveokid soosivad Venemaal käies üha enam Via Hanseaticat / Madis Aesma

    Index Scriptorium Estoniae

    Aesma, Madis

    2005-01-01

    Ajal. Postimees lüh. Pärast Balti riikide ühinemist Euroopa Liiduga kasutavad välismaa veoautojuhid üha enam Euroopast Venemaale sõitmiseks Valga-Tartu-Jõhvi-Narva maanteed, mis moodustab Via Hanseatica ehk Hansatee Eesti osa. Lisa: Via Hanseatica. Kaart: Visa Hanseatica

  3. The HA-incorporated nanostructure of a peptide-drug amphiphile for targeted anticancer drug delivery.

    Science.gov (United States)

    Choi, Huyeon; Jeena, M T; Palanikumar, L; Jeong, Yoojeong; Park, Sooham; Lee, Eunji; Ryu, Ja-Hyoung

    2016-04-25

    A simple peptide based prodrug of camptothecin (CPT) has been synthesised in which the CPT is conjugated to a tripeptide (KCK) via a disulfide linkage (KCK-CPT) and self-assembled into well-defined nanostructures in water depending on the concentration. The hyaluronic acid (HA) complex of KCK-CPT exhibited target specific toxicity with excellent antitumour efficiency.

  4. Euroveokid soosivad Venemaal käies üha enam Via Hanseaticat / Madis Aesma

    Index Scriptorium Estoniae

    Aesma, Madis

    2005-01-01

    Ajal. Postimees lüh. Pärast Balti riikide ühinemist Euroopa Liiduga kasutavad välismaa veoautojuhid üha enam Euroopast Venemaale sõitmiseks Valga-Tartu-Jõhvi-Narva maanteed, mis moodustab Via Hanseatica ehk Hansatee Eesti osa. Lisa: Via Hanseatica. Kaart: Visa Hanseatica

  5. Research on torsional friction behavior and fluid load support of PVA/HA composite hydrogel.

    Science.gov (United States)

    Chen, Kai; Zhang, Dekun; Yang, Xuehui; Cui, Xiaotong; Zhang, Xin; Wang, Qingliang

    2016-09-01

    Hydrogels have been extensively studied for use as synthetic articular cartilage. This study aimed to investigate (1) the torsional friction contact state and the transformation mechanism of PVA/HA composite hydrogel against CoCrMo femoral head and (2) effects of load and torsional angle on torsional friction behavior. The finite element method was used to study fluid load support of PVA/HA composite hydrogel. Results show fluid loss increases gradually of PVA/HA composite hydrogel with torsional friction time, leading to fluid load support decreases. The contact state changes from full slip state to stick-slip mixed state. As the load increases, friction coefficient and adhesion zone increase gradually. As the torsional angle increases, friction coefficient and slip trend of the contact interface increase, resulting in the increase of the slip zone and the reduction of the adhesion zone. Fluid loss increases of PVA/HA composite hydrogel as the load and the torsional angle increase, which causes the decrease of fluid load support and the increase of friction coefficient.

  6. Study of the gamma irradiation effects on the PMMA/HA and PMMA/SW

    Energy Technology Data Exchange (ETDEWEB)

    Silva, P., E-mail: silva@ivic.v [Instituto Venezolano de Investigaciones Cientificas, Centro de Fisica, Carretera Panamericana Km. 11, Caracas 1020-A (Venezuela, Bolivarian Republic of); Albano, C. [Universidad Central de Venezuela, Facultad de Ingenieria (Venezuela, Bolivarian Republic of); Instituto Venezolano de Investigaciones Cientificas, Centro de Quimica (Venezuela, Bolivarian Republic of); Perera, R. [Departamento de Mecanica, Universidad Simon Bolivar, Caracas 1080-A (Venezuela, Bolivarian Republic of); Dominguez, N. [Instituto Venezolano de Investigaciones Cientificas, Centro de Quimica (Venezuela, Bolivarian Republic of)

    2010-03-15

    The behavior of the poly(methyl methacrylate) (PMMA) under the action of gamma radiation has been sufficiently studied. In this work, we present results from melt flow index (MFI), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) of PMMA composites with hydroxyapatite (HA) and seaweed residues (SW) irradiated with gamma rays at 1.08 kGy/h. Composites of PMMA/HA and PMMA/SW with 10%, 20% and 30% of the filler were prepared. The results show an increase in the MFI values with the integral dose of radiation, being consistent with chain-scission reactions. No EPR signal was observed in pure PMMA, while in the composites, the typical EPR signal of the PMMA radicals was observed, which increased with the amount of HA or SW. When comparing the relative intensities of the EPR signals for both types of composites, a slight increase in the concentration of free radicals generated in the sample with SW respect to that of PMMA/HA composite was obtained. A decay of the total free radical concentration was observed as time elapsed.

  7. Jom ha-Šo'a...počátky jednoho svátku

    Directory of Open Access Journals (Sweden)

    Zbyněk Tarant

    2011-12-01

    Full Text Available If one looks at the calendar, one will find there 'International Holocaust Rememberance Day' on 27th of January. This day was set by the UN General Assembly in 2005 and it refers to the anniversary of Auschwitz liberation. However, if one looks at the Israeli calendar, or any of the Jewish Luakh haShannah's, one will find there another day of mourning that is actually far older. The Yom HaShoah was set according to the Hebrew calendar and refers not to the liberation of Auschwitz, but to the Warsaw ghetto uprising. Today, this day of mourning is an interesting relict of the pioneer, upbuilding era that preferred the stories of heroes to those of victims. This article attempts to map the very beginning of the Yom HaShoah commemoration, by using Hebrew sources that were never published before in the Czech language. The story of Yom HaShoah in the context of the young state of Israel in the 1950s is an interesting case-study on the issue of how the contemporary political and public discourse affects the collective memory of  future generations.

  8. Alkali metal cation-hexacyclen complexes: effects of alkali metal cation size on the structure and binding energy.

    Science.gov (United States)

    Austin, C A; Rodgers, M T

    2014-07-24

    Threshold collision-induced dissociation (CID) of alkali metal cation-hexacyclen (ha18C6) complexes, M(+)(ha18C6), with xenon is studied using guided ion beam tandem mass spectrometry techniques. The alkali metal cations examined here include: Na(+), K(+), Rb(+), and Cs(+). In all cases, M(+) is the only product observed, corresponding to