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61.
Elena I. Oprita Lucia Moldovan Oana Craciunescu Wanda Buzgariu Christu Tardei Otilia Zarnescu 《Central European Journal of Biology》2006,1(1):61-72
Collagen-phosphate composites (COL/β-TCP) are novel materials that have the potential to be used as bone analogues. The aim of our study was to develop a porous
bioactive material composed of type I collagen, the main bone protein and tricalcium phosphate, the mineral phase of natural
bone, and investigate their in vitro biocompatibility in a human dermal fibroblast culture system. In order to obtain the
bioactive materials, type I collagen was isolated from bovine tendon and characterized by physicochemical methods. β-TCP was obtained from calcium carbonate by thermal decomposition at 900 °C temperature. The powder was examined with X-ray
diffraction. Two variants of COL/β-TCP scaffolds (P1 and P2) were prepared and examined by scanning electron microscopy. Our results revealed a microporous
structure with small white aggregates of β-TCP, non-homogenous scattered in the collagen framework without any preferential orientation. The biocompatibility of the
obtained scaffolds was tested by biochemical and histological methods on human fibroblast cultures. Both materials acted as
good subtrates for human dermal fibroblast proliferation and migration. 相似文献
62.
Immunotropic influence of 900 MHz microwave GSM signal on human blood immune cells activated in vitro 总被引:1,自引:0,他引:1
Stankiewicz W Dabrowski MP Kubacki R Sobiczewska E Szmigielski S 《Electromagnetic biology and medicine》2006,25(1):45-51
In an earlier study we reported that G(o) phase peripheral blood mononulclear cells (PBMC) exposed to low-level (SAR = 0.18 W/kg) pulse-modulated 1300 MHz microwaves and subsequently cultured, demonstrate changed immune activity (Dabrowski et al., 2003). We investigated whether cultured immune cells induced into the active phases of cell cycle (G(1), S) and then exposed to microwaves will also be sensitive to electromagnetic field. An anechoic chamber of our design containing a microplate with cultured cells and an antenna emitting microwaves (900 MHz simulated GSM signal, 27 V/m, SAR 0.024 W/kg) was placed inside the ASSAB incubator. The microcultures of PBMC exposed to microwaves demonstrated significantly higher response to mitogens and higher immunogenic activity of monocytes (LM index) than control cultures. LM index, described in detail elsewhere (Dabrowski et al., 2001), represents the monokine influence on lymphocyte mitogenic response. The results suggest that immune activity of responding lymphocytes and monocytes can be additionally intensified by 900 MHz microwaves. 相似文献
63.
Marcus A. Mall Brian Button Bjarki Johannesson Zhe Zhou Alessandra Livraghi Ray A. Caldwell Susanne C. Schubert Carsten Schultz Wanda K. O'Neal Sylvain Pradervand Edith Hummler Bernard C. Rossier Barbara R. Grubb Richard C. Boucher 《The Journal of biological chemistry》2010,285(35):26945-26955
Studies in cystic fibrosis patients and mice overexpressing the epithelial Na+ channel β-subunit (βENaC-Tg) suggest that raised airway Na+ transport and airway surface liquid (ASL) depletion are central to the pathogenesis of cystic fibrosis lung disease. However, patients or mice with Liddle gain-of-function βENaC mutations exhibit hypertension but no lung disease. To investigate this apparent paradox, we compared the airway phenotype (nasal versus tracheal) of Liddle with CFTR-null, βENaC-Tg, and double mutant mice. In mouse nasal epithelium, the region that functionally mimics human airways, high levels of CFTR expression inhibited Liddle epithelial Nat channel (ENaC) hyperfunction. Conversely, in mouse trachea, low levels of CFTR failed to suppress Liddle ENaC hyperfunction. Indeed, Na+ transport measured in Ussing chambers (“flooded” conditions) was raised in both Liddle and βENaC-Tg mice. Because enhanced Na+ transport did not correlate with lung disease in these mutant mice, measurements in tracheal cultures under physiologic “thin film” conditions and in vivo were performed. Regulation of ASL volume and ENaC-mediated Na+ absorption were intact in Liddle but defective in βENaC-Tg mice. We conclude that the capacity to regulate Na+ transport and ASL volume, not absolute Na+ transport rates in Ussing chambers, is the key physiologic function protecting airways from dehydration-induced lung disease. 相似文献
64.
65.
Malia M. Edwards Elmina Mammadova-Bach Fabien Alpy Annick Klein Wanda L. Hicks Michel Roux Patricia Simon-Assmann Richard S. Smith Gertraud Orend Jiang Wu Neal S. Peachey J��rgen K. Naggert Olivier Lefebvre Patsy M. Nishina 《The Journal of biological chemistry》2010,285(10):7697-7711
The Neuromutagenesis Facility at the Jackson Laboratory generated a mouse model of retinal vasculopathy, nmf223, which is characterized clinically by vitreal fibroplasia and vessel tortuosity. nmf223 homozygotes also have reduced electroretinogram responses, which are coupled histologically with a thinning of the inner nuclear layer. The nmf223 locus was mapped to chromosome 17, and a missense mutation was identified in Lama1 that leads to the substitution of cysteine for a tyrosine at amino acid 265 of laminin α1, a basement membrane protein. Despite normal localization of laminin α1 and other components of the inner limiting membrane, a reduced integrity of this structure was suggested by ectopic cells and blood vessels within the vitreous. Immunohistochemical characterization of nmf223 homozygous retinas demonstrated the abnormal migration of retinal astrocytes into the vitreous along with the persistence of hyaloid vasculature. The Y265C mutation significantly reduced laminin N-terminal domain (LN) interactions in a bacterial two-hybrid system. Therefore, this mutation could affect interactions between laminin α1 and other laminin chains. To expand upon these findings, a Lama1 null mutant, Lama1tm1.1Olf, was generated that exhibits a similar but more severe retinal phenotype than that seen in nmf223 homozygotes. The increased severity of the Lama1 null mutant phenotype is probably due to the complete loss of the inner limiting membrane in these mice. This first report of viable Lama1 mouse mutants emphasizes the importance of this gene in retinal development. The data presented herein suggest that hypomorphic mutations in human LAMA1 could lead to retinal disease. 相似文献
66.
Foltyn W Kos-Kudła B Siemińska L Zemczak A Strzelczyk J Marek B Kajdaniuk D Nowak M Borowska M Jurecka-Lubienicka B 《Endokrynologia Polska》2006,57(2):160-165
Neuroendocrine tumors are frequently associated with other primary malignancies. Plasmablastic lymphoma is a rare, aggressive neoplasm, derived from large B-cell, associated with human immunodeficiency virus infection. Plasmablastic lymphoma cells share many cytomorphologic and immunophenotypic features with plasmablastic cells, causing some diagnostic problems. We present a unique case of coexisting two very uncommon neoplasms: plasmablastic lymphoma and neuroendocrine carcinoma in 54-years-old men. This is the first report of caecum localization of plasmablastic lymphoma. Presented case images diagnostic problems in rare neoplasms. 相似文献
67.
The high-resolution amplified fragment length polymorphism technique (AFLP), with single PstI restriction endonuclease and two selective primers (PstI-G and PstI-GC), was used for genomotyping and study of the genomic relationships between Genista tinctoria microsymbionts sampled in England, Poland, and Ukraine. Out of 906 amplification products obtained with both selective primers, 537 markers were polymorphic and could be used to differentiate studied nodule isolates. Cluster analysis, based on AFLP patterns from PCR reaction with PstI-G and PstI-GC primers, separated Genista tinctoria rhizobia into three subgroups according to their geographic origin. The results presented in this paper emphasize the role of AFLP analysis in taxonomic and ecological studies of rhizobia. 相似文献
68.
Mutualisms may play an important role in the establishment and invasion success of introduced species, but their influence is little studied. To test whether a lack of root nodule symbionts may limit the performance of invasive legumes, seedlings of Cytisus scoparius were introduced to an old-field habitat and then either inoculated with Bradyrhizobium strains from existing C. scoparius populations, or left uninoculated. In two separate years, inoculation more than doubled average plant biomass. For uninoculated transplants, nodule formation was positively correlated with proximity to plants of the native legume Desmodium canadense , but not related to distance from a second legume species, Apios americana. Polymerase chain reaction assays and DNA sequencing confirmed that bacteria isolated from uninoculated C. scoparius plants were indistinguishable from Bradyrhizobium strains in root nodules of D. canadense . By contrast, bacterial strains associated with A. americana were never found in C. scoparius nodules. Transplants in seven other habitats across a 160 km region also showed a highly significant, fivefold biomass increase in response to inoculation. Thus, colonizing legumes can suffer from a scarcity of nodule symbionts. However, certain indigenous legumes may create favourable microhabitats for invasion, by increasing symbiont availability in their vicinity. 相似文献
69.
70.
Enzymes in Bast Fibrous Plant Processing 总被引:7,自引:0,他引:7
Kozlowski R Batog J Konczewicz W Mackiewicz-Talarczyk M Muzyczek M Sedelnik N Tanska B 《Biotechnology letters》2006,28(10):761-765
The program COST Action 847 Textile Quality and Biotechnology (2000–2005) has given an excellent chance to review the possibilities of the research, aiming at development of the industrial application of enzymes for bast fibrous plant degumming and primary processing. The recent advancements in enzymatic processing of bast fibrous plants (flax, hemp, jute, ramie and alike plants) and related textiles are given. The performance of enzymes in degumming, modification of bast fibres, roving, yarn, related fabrics as well as enzymatic bonding of lignocellulosic composites is provided. 相似文献