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121.
García-Posadas L Contreras-Ruiz L López-García A Villarón Álvarez S Maldonado MJ Diebold Y 《Histochemistry and cell biology》2012,137(2):165-176
The purpose of this study was to demonstrate the presence of the receptor for hyaluronan-mediated motility (RHAMM) in human
conjunctival epithelium and in two widely used cell lines from human corneal (HCE) and conjunctival (IOBA-NHC) epithelia.
We compared the distribution of RHAMM proteins and mRNAs in human ocular surface tissues (corneal, limbal and conjunctival),
HCE and IOBA-NHC cell lines, and corneal and conjunctival epithelia primary samples from healthy donors with the previously
identified hyaluronan receptor CD44. We also aimed to determine if soluble CD44 (sCD44) was present in human tears, as it
could have a role in the interaction of the tear fluid with hyaluronan. Protein expression was evaluated by Western blots
and immunofluorescence microscopy. mRNA expression was evaluated by RT-PCR and Q-PCR. sCD44 was analyzed by ELISA in culture
supernatants and in human tears. We describe the expression of RHAMM in human healthy conjunctiva and in HCE and IOBA-NHC
cells at both protein and mRNA levels, and the presence of sCD44 in human tears. Furthermore, we detected CD44 and sCD44 expression
variations in in vitro inflammatory conditions. This study also focused on the necessary caution with which the conclusions
extracted from cell lines should be made, and in the great value of using primary samples as often as possible. 相似文献
122.
P de Paz Cabello M Fernandez C A Chamorro J G Fernandez J M Villar 《Acta anatomica》1988,132(1):12-16
The neuroectodermal cells of chick embryos have been analyzed during neurulation by stereological and morphometrical ultrastructural methods in an attempt to describe their cytometric evolution. A profound change of cellular form coefficient was observed which is related to the typical process of columnarization of these cells. At stages 7 and 8, the nucleus appeared round in shape, probably due to a loss of pressure of the vitelline inclusions. In this sense, the volume density of these inclusions falls during this period. There was also a significant increase of the nuclear surface density, the significance of which is discussed on the basis of the nucleo-cytoplasmic interchanges and the differentiation process. At the same time, an increase in the number of mitochondria was observed, which is related to the neural folding process. Simultaneously, the amount of rough endoplasmic reticulum increases, presumably related to the remarkable changes of the embryonic extracellular matrix. 相似文献
123.
Esther Vicente Silvia Pérez-Silanes Lidia M. Lima Saioa Ancizu Asunción Burguete Beatriz Solano Raquel Villar Ignacio Aldana Antonio Monge 《Bioorganic & medicinal chemistry》2009,17(1):385-389
New series of 3-phenylquinoxaline 1,4-di-N-oxide with selective activity against Mycobacterium tuberculosis have been prepared and evaluated. Thirty-four of the seventy tested compounds showed an MIC value less than 0.2 μg/mL, a value on the order of the MIC of rifampicin. Furthermore, 45% of the evaluated derivatives showed a good in vitro activity/toxicity ratio. The most active and selective compounds carry a fluorine atom in the quinoxaline 7-position or in the phenyl substituent para-position. In conclusion, the potency, low cytotoxicity and selectivity of these compounds make them valid lead compounds for synthesizing new analogues, particularly compound 7-methyl-3-(4’-fluoro)phenylquinoxaline-2-carbonitrile 1,4-di-N-oxide (MIC <0.2 μg/mL and SI >500). 相似文献
124.
Emilie Saby Jesper Buchhave Poulsen Just Justesen Merike Kelve Maria Jesus Uriz 《Biochimie》2009,91(11-12):1531-1534
Sponges [porifera], the most ancient metazoans, contain modules related to the vertebrate immune system, including the 2′,5′-oligoadenylate synthetase (OAS). The components of the antiviral 2′,5′-oligoadenylate (2–5A) system (OAS, 2′-Phosphodiesterase (2′-PDE) and RNAse L) of vertebrates have not all been identified in sponges. Here, we demonstrate for the first time that in addition to the OAS activity, sponges possess a 2′-PDE activity, which highlights the probable existence of a premature 2–5A system. Indeed, Suberites domuncula and Crella elegans exhibited this 2–5A degrading activity. Upon this finding, two out of three elements forming the 2–5A system have been found in sponges, only a endoribonuclease, RNAse L or similar, has to be found. We suspect the existence of a complex immune system in sponges, besides the self/non-self recognition system and the use of phagocytosis and secondary metabolites against pathogens. 相似文献
125.
Ugo Maninchedda Olivier M. Lepage Monika Gangl Sandrine Hilairet Bernard Remandet Francoise Meot Geraldine Penarier Emilie Segard Pierre Cortez Christian Jorgensen Régis Steinberg 《PloS one》2015,10(2)
The aim of this work was to develop an equine metacarpophalangeal joint model that induces osteoarthritis that is not primarily mediated by instability or inflammation. The study involved six Standardbred horses. Standardized cartilage surface damage or “grooves” were created arthroscopically on the distal dorsal aspect of the lateral and medial metacarpal condyles of a randomly chosen limb. The contralateral limb was sham operated. After 2 weeks of stall rest, horses were trotted 30 minutes every other day for 8 weeks, then evaluated for lameness and radiographed. Synovial fluid was analyzed for cytology and biomarkers. At 10 weeks post-surgery, horses were euthanized for macroscopic and histologic joint evaluation. Arthroscopic grooving allowed precise and identical damage to the cartilage of all animals. Under the controlled exercise regime, this osteoarthritis groove model displayed significant radiographic, macroscopic, and microscopic degenerative and reactive changes. Histology demonstrated consistent surgically induced grooves limited to non-calcified cartilage and accompanied by secondary adjacent cartilage lesions, chondrocyte necrosis, chondrocyte clusters, cartilage matrix softening, fissuring, mild subchondral bone inflammation, edema, and osteoblastic margination. Synovial fluid biochemistry and cytology demonstrated significantly elevated total protein without an increase in prostaglandin E2, neutrophils, or chondrocytes. This equine metacarpophalangeal groove model demonstrated that standardized non-calcified cartilage damage accompanied by exercise triggered altered osteochondral morphology and cartilage degeneration with minimal or inefficient repair and little inflammatory response. This model, if validated, would allow for assessment of disease processes and the effects of therapy. 相似文献
126.
Marine Henry Louis-Marie Bobay Anne Chevallereau Emilie Saussereau Pieter-Jan Ceyssens Laurent Debarbieux 《PloS one》2015,10(1)
In a previous study, six virulent bacteriophages PAK_P1, PAK_P2, PAK_P3, PAK_P4, PAK_P5 and CHA_P1 were evaluated for their in vivo efficacy in treating Pseudomonas aeruginosa infections using a mouse model of lung infection. Here, we show that their genomes are closely related to five other Pseudomonas phages and allow a subdivision into two clades, PAK_P1-like and KPP10-like viruses, based on differences in genome size, %GC and genomic contents, as well as number of tRNAs. These two clades are well delineated, with a mean of 86% and 92% of proteins considered homologous within individual clades, and 25% proteins considered homologous between the two clades. By ESI-MS/MS analysis we determined that their virions are composed of at least 25 different proteins and electron microscopy revealed a morphology identical to the hallmark Salmonella phage Felix O1. A search for additional bacteriophage homologs, using profiles of protein families defined from the analysis of the 11 genomes, identified 10 additional candidates infecting hosts from different species. By carrying out a phylogenetic analysis using these 21 genomes we were able to define a new subfamily of viruses, the Felixounavirinae within the Myoviridae family. The new Felixounavirinae subfamily includes three genera: Felixounalikevirus, PAK_P1likevirus and KPP10likevirus. Sequencing genomes of bacteriophages with therapeutic potential increases the quantity of genomic data on closely related bacteriophages, leading to establishment of new taxonomic clades and the development of strategies for analyzing viral genomes as presented in this article. 相似文献
127.
128.
Hip arthroscopy has continued to expand its horizons in treating many conditions other than femoroacetabular impingement (FAI). However, the results of hip arthroscopy are known to be poor if the degree of articular cartilage damage is significant. We wanted to assess, whether the procedure might have a role in the management of young and active patients with advanced osteoarthritis (OA) and whether it should be offered as a treatment modality. 77 consecutive patients with Tönnis grade 2 and 3 osteoarthritis of the hip who had undergone hip arthroscopy were included in the study. Patients'' medical notes, plain radiographs and outcome scores (modified Harris hip score (mHHS), non-arthritic hip score (NAHS)) preoperatively and postoperatively at six weeks, six months, one year and annually thereafter, were analysed. 77 patients consisted of 63 men and 14 women with mean follow-up of 2.8 years (2.2 to 4.2) and mean age at surgery of 43 years (19 to 64). The mean preoperative mHHS and NAHS scores were 58 (28 to 87) and 64 (27 to 93) respectively. The mean improvements in both the mHHS and NAHS scores were significant (p = 0.003 and p = 0.0001 for mHHS at one and two years, p = 0.002 and p = 0.0003 for NAHS at one and two years, respectively). There were 34 patients (44%) who required a total hip replacement at mean of 18 months (6 to 48) after hip arthroscopy. We conclude that hip arthroscopy improves outcome scores in 56% of patients with severe OA of the hip (Tönnis grade 2 and 3) for at least two years after surgery. We thus consider the procedure to be a reasonable option for patients with hip OA, although success of the procedure will be less than if undertaken for certain other conditions. 相似文献
129.
Cressida A. Madigan Amanda Jezek Martinot Jun-Rong Wei Ashoka Madduri Tan-Yun Cheng David C. Young Emilie Layre Jeffrey P. Murry Eric J. Rubin D. Branch Moody 《PLoS pathogens》2015,11(3)
The prolonged survival of Mycobacterium tuberculosis (M. tb) in the host fundamentally depends on scavenging essential nutrients from host sources. M. tb scavenges non-heme iron using mycobactin and carboxymycobactin siderophores, synthesized by mycobactin synthases (Mbt). Although a general mechanism for mycobactin biosynthesis has been proposed, the biological functions of individual mbt genes remain largely untested. Through targeted gene deletion and global lipidomic profiling of intact bacteria, we identify the essential biochemical functions of two mycobactin synthases, MbtK and MbtN, in siderophore biosynthesis and their effects on bacterial growth in vitro and in vivo. The deletion mutant, ΔmbtN, produces only saturated mycobactin and carboxymycobactin, demonstrating an essential function of MbtN as the mycobactin dehydrogenase, which affects antigenicity but not iron uptake or M. tb growth. In contrast, deletion of mbtK ablated all known forms of mycobactin and its deoxy precursors, defining MbtK as the essential acyl transferase. The mbtK mutant showed markedly reduced iron scavenging and growth in vitro. Further, ΔmbtK was attenuated for growth in mice, demonstrating a non-redundant role of hydroxamate siderophores in virulence, even when other M. tb iron scavenging mechanisms are operative. The unbiased lipidomic approach also revealed unexpected consequences of perturbing mycobactin biosynthesis, including extreme depletion of mycobacterial phospholipids. Thus, lipidomic profiling highlights connections among iron acquisition, phospholipid homeostasis, and virulence, and identifies MbtK as a lynchpin at the crossroads of these phenotypes. 相似文献
130.
Application of oncoproteomics to aberrant signalling networks in changing the treatment paradigm in acute lymphoblastic leukaemia 下载免费PDF全文
Elena López Villar Xiangdong Wang Luis Madero William C. Cho 《Journal of cellular and molecular medicine》2015,19(1):46-52
Oncoproteomics is an important innovation in the early diagnosis, management and development of personalized treatment of acute lymphoblastic leukaemia (ALL). As inherent factors are not completely known – e.g. age or family history, radiation exposure, benzene chemical exposure, certain viral exposures such as infection with the human T‐cell lymphoma/leukaemia virus‐1, as well as some inherited syndromes may raise the risk of ALL – each ALL patient may modify the susceptibility of therapy. Indeed, we consider these unknown inherent factors could be explained via coupling cytogenetics plus proteomics, especially when proteins are the ones which play function within cells. Innovative proteomics to ALL therapy may help to understand the mechanism of drug resistance and toxicities, which in turn will provide some leads to improve ALL management. Most important of these are shotgun proteomic strategies to unravel ALL aberrant signalling networks. Some shotgun proteomic innovations and bioinformatic tools for ALL therapies will be discussed. As network proteins are distinctive characteristics for ALL patients, unrevealed by cytogenetics, those network proteins are currently an important source of novel therapeutic targets that emerge from shotgun proteomics. Indeed, ALL evolution can be studied for each individual patient via oncoproteomics. 相似文献