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991.
Bárbara Santos Pires da Silva Eloísa Bonfá Júlio César Bertacini de Moraes Carla Gonçalves Schain Saad Ana Cristina de Medeiros Ribeiro Célio Roberto Gonçalves Jozélio Freire de Carvalho 《Biologicals》2010,38(5):567-569
The objective of this study was to evaluate the influence of anti-tumor necrosis factor (anti-TNF) in juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS) or psoriatic arthritis (PsA). Sixty-two patients were investigated: 7 JIA; 37 AS; and 18 PsA. Caucasian race accounted for 79% and 29% were female. Mean age was 40.4 ± 12.6years. None of the patients had a history of diabetes, and none had used oral hypoglycemic agents or insulin. Treatment was with adalimumab, infliximab and etanercept. Glucose, inflammatory markers and prednisone dose were assessed at baseline, as well as after three and six months of treatment. The mean erythrocyte sedimentation rate was significantly lower at three months and six months than at baseline (13.7 ± 18.0 and 18 ± 22.5 vs. 27.9 ± 23.4 mm; p = 0.001). At baseline, three months and six months, we found the following: mean C-reactive protein levels were comparable (22.1 ± 22.7, 14.5 ± 30.7 and 16.0 ± 23.8 mg/L, respectively; p = 0.26); mean glucose levels remained unchanged (90.8 ± 22.2 mg/dl, 89.5 ± 14.6 mg/dl and 89.8 ± 13.6 mg/dl, respectively; p = 0.91); and mean prednisone doses were low and stable (3.9 ± 4.9 mg/day, 3.7 ± 4.8 mg/day and 2.6 ± 4.0 mg/day, respectively; p = 0.23). During the first six months of treatment, anti-TNF therapy does not seem to influence glucose metabolism in JIA, AS or PsA. 相似文献
992.
Lorena Rebecchi Roberto Guidetti Simona Borsari Tiziana Altiero Roberto Bertolani 《Hydrobiologia》2006,558(1):23-30
It is not rare to find in references that anhydrobiotic tardigrades can survive for more than a century. However, a closer
look at the empirical evidence provides very little support that tardigrades are capable of surviving dried for such a long
time. In order to resolve this discrepancy, we carried out a study to evaluate the long-term survival of naturally dried tardigrades.
A large fragment of dry lichen (Xanthoria parietina) was collected in the field two days after a rainy day in 1999. The dry lichen was stored inside a paper bag in the laboratory
at room temperature and humidity and under atmospheric oxygen exposure. Replicates of the dry lichen were re-hydrated after
various time periods of storage, with all tardigrades extracted and the survivors enumerated. Five species of tardigrades
were found, but two of them only occasionally. Ramazzottius oberhaeuseri, Echiniscus testudo and Echiniscus trisetosus were sufficiently represented for statistical analysis. At the beginning of the experiment 91.1% of R. oberhaeuseri and 71.7% of Echiniscus spp. were alive. R. oberhaeuseri survived up to 1604 days, while Echiniscus spp. lived up to 1085 days. Recovery after four years of anhydrobiosis has to be considered a very good long-term survival,
which is important from an ecological and evolutionary point of view. 相似文献
993.
Three new alloantigenic specificities of human major histocompatibility complex class 11 molecules have been defined by testing the reactivity of alloantisera at the molecular level. Two of these specificities identify different DR4 haplotypes. The Fe75 specificity is associated with the DR4/DW10 haplotype and the CBC/MRG6 specificity with the DR4/DKT2 haplotype. Both are supertypic specificities and are associated with other DR specificities as well. Both specificities are carried by class 11 molecules belonging to the first DR subset. Together with previously described determinants, these specificities contribute to serological discrimination of the different DR4 haplotypes. 相似文献
994.
Control in vitro tick (Boophilus microplus; Acari: Ixodidae) through plant extracts. Hydro-alcohol extracts of ten tropical plants were tested by the immersion method on mature ticks (Boophilus microplus Canestrini 1887). The biological evaluation was made with raw hydro alcoholic extracts (R-OH) to determine the most promissory compounds, which later were fractioned in their polar and non-polar parts. The polar parts showed a significantly inferior effect. The species that produced the highest mortality were Zizigium aromaticum, Morus alba, Piper nigrum and the mixture of Allium sativum- Z. aromaticum (all non-polar); on oviposition: M. alba, P. nigrum and the mixture of A. sativum - Z. aromaticum (all non-polar); on eclosion: P. nigrum, Z. aromaticum, Echinacea angustiofilia, Poligonum punctatum, M. alba and the mixture of A. sativum-Z. aromaticum (all non-polar): on control percentage: P. nigrum, E. angustifolia, P. punctatum and M. alba (all non-polar, except for M. alba in which both fractions showed important activity); and finally, on the percentage of oviposition inhibition: P. nigrum, E. angustifolia, P. punctatum, Gliricidia sepium and M. alba. 相似文献
995.
Penolazzi L Lambertini E Tavanti E Torreggiani E Vesce F Gambari R Piva R 《Cell biology international》2008,32(2):320-325
We have used cytokine protein array to analyze the secretion of cytokines from an osteoblastic clone derived from human umbilical cord blood mesenchymal stem cells (MSCs) cultured in an osteogenic differentiation medium. The analysis demonstrated the unexpected ability of osteoblast committed cells and their early progenitors to produce significant amounts of a range of soluble immune mediators without in vitro exposure to clinically relevant bacterial pathogens. The cells were expanded and their osteogenic potential analyzed over 45 days of culture was revealed by the expression of osteoblast-specific markers (alkaline phosphatase and Runx2), and by matrix mineralization. Over this culture period, the cells secreted particularly high levels of IL-8, MCP-1 and VEGF, but did not express IL-2, IL-7, IL-17, eotaxin, G-CSF and IFN-gamma. These findings should encourage the use of human umbilical cord blood as a potential stem cells source for bone regeneration. 相似文献
996.
The purple membrane of Halobacterium halobium acts as a light-driven proton pump, ejecting protons from the cell interior into the medium and generating an electrochemical proton gradient across the cell membrane. However, the typical response of cells to light as measured with a pH electrode in the medium consists of an initial net inflow of protons which subsides and is then replaced by a net outflow which exponentially approaches a new lower steady state pH level. When the light is turned off a small transient acidification occurs before the pH returns to the original dark level. We present experiments suggesting that the initial inflow of protons is triggered by the beginning ejection of protons through the purple membrane and that the initial inflow rate is larger than the continuing light-driven outflow. When the initial inflow has decreased exponentially to a small value, the outflow dominates and causes the net acidification of the medium.The initial inflow is apparently driven by a pre-existing electrochemical gradient across the membrane, which the cells can maintain for extended times in the absence of light and oxygen. Treatments which collapse this gradient such as addition of small concentrations of uncouplers abolish the initial inflow.The triggered inflow occurs through the ATPase and is accompanied by ATP synthesis. Inhibitors of the ATPase such as N,N′-dicyclohexylcarbodiimide (DCCD) inhibit ATP synthesis and abolish the inflow. They also abolish the transient light-off acidification, which is apparently caused by a short burst of ATP hydrolysis before the enzyme is blocked by its endogenous inhibitor.Similar transient inflows and outflows of protons are also observed when anaerobic cells are exposed to short oxygen pulses. 相似文献
997.
Anna Mara Scandroglio Gabriele Finco Marina Pieri Roberto Ascari Maria Grazia Calabrò Daiana Taddeo Francesca Isella Annalisa Franco Mario Musu Giovanni Landoni Ottavio Alfieri Alberto Zangrillo 《BMC anesthesiology》2015,15(1)
Background
The elderly undergo cardiac surgery more and more frequently, often present multiple comorbidities, assume chronic therapies, and present a unique physiology. Aim of our study was to analyze the experience of a referral cardiac surgery center with all types of cardiac surgery interventions performed in patients ≥80 years old over a six years’ period.Methods
A retrospective observational study performed in a university hospital. 260 patients were included in the study (3.5% of the patients undergoing cardiac surgery in the study period).Results
Mean age was 82 ± 1.8 years. Eighty-five percent of patients underwent elective surgery, 15% unplanned surgery and 4.2% redo surgery. Intervention for aortic valve pathology and coronary artery bypass grafting were performed in 51% and 46% of the patients, respectively. Interventions involving the mitral valve were the 26% of the total, those on the tricuspid valve were 13% and those on the ascending aortic arch the 9.6%. Postoperative low output syndrome was identified in 44 patients (17%). Mortality was 3.9% and most of the patients (91%) were discharged from hospital in good clinical conditions. Hospital mortality was lower in planned vs unplanned surgery: 3.8% vs 14% respectively. Chronic obstructive pulmonary disease (OR 9.106, CI 2.275 – 36.450) was the unique independent predictor of mortality.Conclusions
Clinicians should be aware that cardiac surgery can be safely performed at all ages, that risk stratification is mandatory and that hemodynamic treatment to avoid complications is expected.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2253-15-15) contains supplementary material, which is available to authorized users. 相似文献998.
Francesco Pantano Matteo Santoni Giuseppe Procopio Mimma Rizzo Roberto Iacovelli Camillo Porta Alessandro Conti Antonio Lugini Michele Milella Luca Galli Cinzia Ortega Francesco Maria Guida Marianna Silletta Giovanni Schinzari Elena Verzoni Daniela Modica Pierfilippo Crucitti Annamaria Rauco Alessandra Felici Valentina Ballatore Stefano Cascinu Giuseppe Tonini Giacomo Carteni Antonio Russo Daniele Santini 《PloS one》2015,10(4)
Background
Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of metastatic renal cell carcinoma (mRCC). We aimed to assess the association between the baseline values and treatmentrelated modifications of total serum cholesterol (C), triglycerides (T), body mass index (BMI), fasting blood glucose level (FBG) and blood pressure (BP) levels and the outcome of patients treated with everolimus for mRCC.Methods
177 patients were included in this retrospective analysis. Time to progression (TTP), clinical benefit (CB) and overall survival (OS) were evaluated.Results
Basal BMI was significantly higher in patients who experienced a CB (p=0,0145). C,T and C+T raises were significantly associated with baseline BMI (p=0.0412, 0.0283 and 0.0001). Median TTP was significantly longer in patients with T raise compared to patients without T (10 vs 6, p=0.030), C (8 vs 5, p=0.042) and C+T raise (10.9 vs 5.0, p=0.003). At the multivariate analysis, only C+T increase was associated with improved TTP (p=0.005). T raise (21.0 vs 14.0, p=0.002) and C+T increase (21.0 vs 14.0, p=0.006) were correlated with improved OS but were not significant at multivariate analysis.Conclusion
C+T raise is an early predictor for everolimus efficacy for patients with mRCC. 相似文献999.
1000.
Michael Fernández Alex Fragoso Roberto Cao Maysa Baños Maria L. Villalonga Reynaldo Villalonga 《Biotechnology letters》2002,24(17):1455-1459
The monoaldehyde derivative of -cyclodextrin was attached to trypsin via reductive alkylation with NaBH4. The thermostability was enhanced from 49.5 °C to 60 °C for modified trypsin. The activation free energy of thermal inactivation at 50 °C was increased by 3.2 kJ mol–1. The conjugated enzyme retained 100% of its initial activity after 3 h incubation at pH 9. 相似文献