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91.
Chlamydia pneumoniae is an obligate intracellular Gram-negative bacterium that causes recurrent pharyngitis, pneumonia and chronic inflammation induced by cycles of persistence and productive infection that might also explain the association with chronic diseases. The aim of this study was to determine whether C. pneumoniae can invade and survive within human osteoblasts and whether this infection elicits the secretion of proinflammatory cytokines.Our results demonstrated that C. pneumoniae was able to infect the SaOS-2 osteoblastic cell line and to replicate in the osteoblasts in a time-dependent manner and was associated to an increase in the cell number and cell viability.In addition, infection of the SaOS-2 cell line with C. pneumoniae at MOI of 4 is correlated to a proinflammatory response. Infected osteoblasts produced increased levels of cytokines IL-6, IL-8, IL-17, and IL-23. The production of cytokines increased with subsequent interaction between osteoblasts and monocytes and the maximum levels of cytokines released were detected 72 h after infection with C. pneumoniae. Thus, controlling the release of chemokines, e.g., IL-23, may be a therapeutic strategy for preventing inflammatory bone disease and counteract inflammation and bone destruction. 相似文献
92.
Brian J O’Connor Sara Collarini Gianluigi Poli Caterina Brindicci Monica Spinola Daniela Acerbi Peter J Barnes Brian Leaker 《BMC pulmonary medicine》2011,11(1):1-8
Background
Airway Bypass is a catheter-based, bronchoscopic procedure in which new passageways are created that bypass the collapsed airways, enabling trapped air to exit the lungs. The Exhale Airway Stents for Emphysema (EASE) Trial was designed to investigate whether Exhale® Drug-Eluting Stents, placed in new passageways in the lungs, can improve pulmonary function and reduce breathlessness in severely hyperinflated, homogeneous emphysema patients (NCT00391612).Methods/Design
The multi-center, randomized, double-blind, sham-controlled trial design was posted on http://www.clinicaltrials.gov in October 2006. Because Bayesian statistics are used for the analysis, the proposed enrollment ranged from 225 up to 450 subjects at up to 45 institutions. Inclusion criteria are: high resolution CT scan with evidence of homogeneous emphysema, post-bronchodilator pulmonary function tests showing: a ratio of FEV1/FVC < 70%, FEV1≤50% of predicted or FEV1 < 1 liter, RV/TLC≥0.65 at screening, marked dyspnea score ≥2 on the modified Medical Research Council scale of 0-4, a smoking history of at least 20 pack years and stopped smoking for at least 8 weeks prior to enrollment. Following 16 to 20 supervised pulmonary rehabilitation sessions, subjects were randomized 2:1 to receive either a treatment (Exhale® Drug-Eluting Stent) or a sham bronchoscopy. A responder analysis will evaluate the co-primary endpoints of an FVC improvement ≥12% of the patient baseline value and modified Medical Research Council dyspnea scale improvement (reduction) ≥1 point at the 6-month follow-up visit.Discussion
If through the EASE Trial, Airway Bypass is shown to improve pulmonary function and reduce dyspnea while demonstrating an acceptable safety profile, then homogeneous patients will have a minimally invasive treatment option with meaningful clinical benefit.Trial Registration
ClinicalTrials.gov: NCT00391612 相似文献93.
Calcium-ATPase pumps are critical in most cells, to sequester calcium into intracytoplasmic stores and regulate general calcium signalling. In addition, cell-specific needs for calcium signals have been described and employ a diversity of calcium ATPases in adult tissues and oocytes. A major family of such calcium pumps is ATP2A/SERCA family, for Sarcoplasmic/Endoplasmic Reticulum Calcium ATPases. Although largely studied in adults, the developmental expression of the atp2a/serca genes remains unknown. Here, we provide genome organisation in Xenopuslaevis and tropicalis and phylogeny of atp2a/serca genes in craniates. We detail embryonic expression for the three X. laevis atp2a/serca genes. We found that the three atp2a/serca genes are strongly conserved among vertebrates and display complementary and tissue-specific expression in embryos. These expression patterns present variations when compared to the data reported in adults. Atp2a1/serca1 is expressed as soon as the end of gastrulation in a subset of the myod-positive cells, and later labels prospective slow muscle cells in the superficial part of the somite. In contrast atp2a2/serca2 is found in a larger subset of cells, but is not ubiquitous as reported in adults. Notably, atp2a2/serca2 is prominently expressed in the neural-related tissues, i.e. the neural plate, cement gland, but is excluded from premigratory neural crest. Finally, atp2a3/serca3 expression is restricted to the ectoderm throughout development. 相似文献
94.
95.
Fookes M Schroeder GN Langridge GC Blondel CJ Mammina C Connor TR Seth-Smith H Vernikos GS Robinson KS Sanders M Petty NK Kingsley RA Bäumler AJ Nuccio SP Contreras I Santiviago CA Maskell D Barrow P Humphrey T Nastasi A Roberts M Frankel G Parkhill J Dougan G Thomson NR 《PLoS pathogens》2011,7(8):e1002191
The genus Salmonella contains two species, S. bongori and S. enterica. Compared to the well-studied S. enterica there is a marked lack of information regarding the genetic makeup and diversity of S. bongori. S. bongori has been found predominantly associated with cold-blooded animals, but it can infect humans. To define the phylogeny of this species, and compare it to S. enterica, we have sequenced 28 isolates representing most of the known diversity of S. bongori. This cross-species analysis allowed us to confidently differentiate ancestral functions from those acquired following speciation, which include both metabolic and virulence-associated capacities. We show that, although S. bongori inherited a basic set of Salmonella common virulence functions, it has subsequently elaborated on this in a different direction to S. enterica. It is an established feature of S. enterica evolution that the acquisition of the type III secretion systems (T3SS-1 and T3SS-2) has been followed by the sequential acquisition of genes encoding secreted targets, termed effectors proteins. We show that this is also true of S. bongori, which has acquired an array of novel effector proteins (sboA-L). All but two of these effectors have no significant S. enterica homologues and instead are highly similar to those found in enteropathogenic Escherichia coli (EPEC). Remarkably, SboH is found to be a chimeric effector protein, encoded by a fusion of the T3SS-1 effector gene sopA and a gene highly similar to the EPEC effector nleH from enteropathogenic E. coli. We demonstrate that representatives of these new effectors are translocated and that SboH, similarly to NleH, blocks intrinsic apoptotic pathways while being targeted to the mitochondria by the SopA part of the fusion. This work suggests that S. bongori has inherited the ancestral Salmonella virulence gene set, but has adapted by incorporating virulence determinants that resemble those employed by EPEC. 相似文献
96.
Giammanco GM Pepe A Aleo A D'Agostino V Milone S Mammina C 《The new microbiologica》2011,34(2):179-185
Pecorino Siciliano (PS) "primosale" is a traditional Sicilian fresh soft cheese made from sheep's milk. Short-ripening time and production from unpasteurized or raw milk can facilitate bacterial contamination of PS "primosale". The microbiological quality of "primosale" on retail sale in the street markets of Palermo, Italy was studied by detecting the common food pathogens Listeria monocytogenes and Staphylococcus aureus and indicator microorganisms, such as Escherichia coli, Enterobacteriaceae and Staphylococcaceae. In our study, 4% and 44% of the samples, respectively, did not comply with the acceptability levels fixed by European regulations for S. aureus and E. coli. A high contamination of bacteria belonging to Enterobacteriaceae and Staphylococcaceae was found in 42% and 50% of the cheeses analyzed, respectively. Such results indicate poor husbandry and poor hygiene practices during milk collection or preservation or during cheese production processes and handling. In addition, the retail sale conditions may have played a role in cheese contamination since a correlation was found between poor microbiological quality and some selling parameters. This study emphasizes the need to improve production hygiene throughout the PS food chain in line with the traditional cheese-making procedures. Labelling of PS with clear information on whether the cheese was prepared from raw milk also requires improvement. 相似文献
97.
Cortis C Tessitore A Lupo C Pesce C Fossile E Figura F Capranica L 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(1):135-142
This study aimed to verify whether basketball players are able to maintain strength (handgrip), jump (countermovement jump [CMJ]), sprint (10 m and 10 m bouncing the ball [10 mBB]), and interlimb coordination (i.e., synchronized hand and foot flexions and extensions at 80, 120, and 180 bpm) performances at the end of their game. Ten young (age 15.7 ± 0.2 years) male basketball players volunteered for this study. During the friendly game, heart rate (HR), rate of perceived exertion (RPE), and rate of muscle pain (RMP) were assessed to evaluate the exercise intensity. Overall, players spent 80% of the time playing at intensities higher than 85% HRmax. Main effects (p < 0.05) for game periods emerged for HR and the number of players involved in a single action, with lower occurrence of maximal efforts and higher involvement of teammates after the first 2 periods. At the end of the game, players reported high (p < 0.05) RPE (15.7 ± 2.4) and RMP (5.2 ± 2.3) values; decreased (p < 0.05) sprint capabilities (10 m: pre = 1.79 ± 0.09 seconds, post = 1.84 ± 0.08 seconds; 10 mBB: pre = 1.81 ± 0.11 seconds, post = 1.96 ± 0.08 seconds); increased (p < 0.05) interlimb coordination at 180 bpm (pre = 33.3 ± 20.2 seconds, post = 43.9 ± 19.8 seconds); and maintained jump (pre = 35.2 ± 5.2 cm, post = 35.7 ± 5.2 cm), handgrip (pre = 437 ± 73 N, post = 427 ± 55 N), and coordinative performances at lower frequencies of executions (80 bpm: pre = 59.7 ± 1.3 seconds, post = 60.0 ± 0.0 seconds; 120 bpm: pre = 54.7 ± 12.3 seconds, post = 57.3 ± 6.7 seconds). These findings indicate that the heavy load of the game exerts beneficial effects on the efficiency of executive and attentive control functions involved in complex motor behaviors. Coaches should structure training sessions that couple intense physical exercises with complex coordination tasks to improve the attentional capabilities of the players. 相似文献
98.
Mese G Sellitto C Li L Wang HZ Valiunas V Richard G Brink PR White TW 《Molecular biology of the cell》2011,22(24):4776-4786
Mutations in the GJB2 gene (Cx26) cause deafness in humans. Most are loss-of-function mutations and cause nonsyndromic deafness. Some mutations produce a gain of function and cause syndromic deafness associated with skin disorders, such as keratitis-ichthyosis-deafness syndrome (KIDS). Cx26-G45E is a lethal mutation linked to KIDS that forms constitutively active connexin hemichannels. The pathomechanism(s) by which mutant Cx26 hemichannels perturb normal epidermal cornification are poorly understood. We created an animal model for KIDS by generating an inducible transgenic mouse expressing Cx26-G45E in keratinocytes. Cx26-G45E mice displayed reduced viability, hyperkeratosis, scaling, skin folds, and hair loss. Histopathology included hyperplasia, acanthosis, papillomatosis, increased cell size, and osteal plugging. These abnormalities correlated with human KIDS pathology and were associated with increased hemichannel currents in transgenic keratinocytes. These results confirm the pathogenic nature of the G45E mutation and provide a new model for studying the role of aberrant connexin hemichannels in epidermal differentiation and inherited connexin disorders. 相似文献
99.
100.
Esposito G Scuderi C Valenza M Togna GI Latina V De Filippis D Cipriano M Carratù MR Iuvone T Steardo L 《PloS one》2011,6(12):e28668
Peroxisome proliferator-activated receptor-γ (PPARγ) has been reported to be involved in the etiology of pathological features of Alzheimer's disease (AD). Cannabidiol (CBD), a Cannabis derivative devoid of psychomimetic effects, has attracted much attention because of its promising neuroprotective properties in rat AD models, even though the mechanism responsible for such actions remains unknown. This study was aimed at exploring whether CBD effects could be subordinate to its activity at PPARγ, which has been recently indicated as its putative binding site. CBD actions on β-amyloid-induced neurotoxicity in rat AD models, either in presence or absence of PPAR antagonists were investigated. Results showed that the blockade of PPARγ was able to significantly blunt CBD effects on reactive gliosis and subsequently on neuronal damage. Moreover, due to its interaction at PPARγ, CBD was observed to stimulate hippocampal neurogenesis. All these findings report the inescapable role of this receptor in mediating CBD actions, here reported. 相似文献