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991.
Zieg J Blahova K Seeman T Bronsky J Dvorakova H Pechova M Janda J Matousovic K 《Nephrology (Carlton, Vic.)》2011,16(6):595-598
Aim: Obstructive uropathies (OU) in childhood constitute one of the major causes of chronic renal insufficiency. Transforming growth factor‐β1 (TGF‐β1) is considered to be the major fibrogenic growth factor. The aim of the present study was to investigate urinary TGF‐β1 levels in children with obstructive and non‐obstructive uropathies (NOU). Methods: This study involved 19 children with OU, 11 children with non‐obstructive hydronephrosis and 21 healthy children. Urinary TGF‐β1, proteinuria, microalbuminuria and urinary α1‐microglobulin were measured, and renal function was assesed. The results were statistically analyzed. Results: Mean urinary TGF‐β1 concentrations in patients with OU were significantly higher than those with NOU (4.14 ± 0.67 creatinine vs 1.80 ± 0.24 pg/mmol creatinine, P < 0.05) and healthy controls (1.66 ± 0.28 pg/mmol creatinine, P < 0.05). Positive correlations of urinary TGF‐β1 concentrations with proteinuria (r = 0.87, P < 0.0001) and urinary α1‐microglobulin (r = 0.82, P = 0.0002) were found in patients with OU. Conclusion: Children with OU have higher urinary TGF‐β1 than children with NOU. Urinary TGF‐β1 may be a useful non‐invasive tool for the differential diagnosis between OU and NOU in children. A positive correlation of TGF‐β1 with markers of renal tissue damage in patients with OU was found. 相似文献
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We used fMRI to assess the neural correlates of autobiographical, semantic, and episodic memory retrieval in healthy young and older adults. Participants were tested with an event-related paradigm in which retrieval demand was the only factor varying between trials. A spatio-temporal partial least square analysis was conducted to identify the main patterns of activity characterizing the groups across conditions. We identified brain regions activated by all three memory conditions relative to a control condition. This pattern was expressed equally in both age groups and replicated previous findings obtained in a separate group of younger adults. We also identified regions whose activity differentiated among the different memory conditions. These patterns of differentiation were expressed less strongly in the older adults than in the young adults, a finding that was further confirmed by a barycentric discriminant analysis. This analysis showed an age-related dedifferentiation in autobiographical and episodic memory tasks but not in the semantic memory task or the control condition. These findings suggest that the activation of a common memory retrieval network is maintained with age, whereas the specific aspects of brain activity that differ with memory content are more vulnerable and less selectively engaged in older adults. Our results provide a potential neural mechanism for the well-known age differences in episodic/autobiographical memory, and preserved semantic memory, observed when older adults are compared with younger adults. 相似文献
995.
Combined exposure of Japanese quails to cyanotoxins, Newcastle virus and lead: oxidative stress responses 总被引:1,自引:0,他引:1
Paskova V Veronika P Paskerova H Hana P Pikula J Jiri P Bandouchova H Hana B Sedlackova J Jana S Hilscherova K Klara H 《Ecotoxicology and environmental safety》2011,74(7):2082-2090
Wild birds are continually exposed to many anthropogenic and natural stressors in their habitats. Over the last decades, mass mortalities of wild birds constitute a serious problem and may possibly have more causations such as natural toxins including cyanotoxins, parasitic diseases, industrial chemicals and other anthropogenic contaminants. This study brings new knowledge on the effects of controlled exposure to multiple stressors in birds. The aim was to test the hypothesis that influence of cyanobacterial biomass, lead and antigenic load may combine to enhance the effects on birds, including modulation of antioxidative and detoxification responses. Eight treatment groups of model species Japanese quail (Coturnix coturnix japonica) were exposed to various combinations of these stressors. The parameters of detoxification and oxidative stress were studied in liver and heart after 30 days of exposure. The antioxidative enzymatic defense in birds seems to be activated quite efficiently, which was documented by the elevated levels and activities of antioxidative and detoxification compounds and by the low incidence of damage to lipid membranes. The greatest modulations of glutathione level and activities of glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and lipid peroxidation were shown mostly in the groups with combined multiple exposures. The results indicate that the antioxidative system plays an important role in the protective response of the tissues to applied stressors and that its greater induction helps to protect the birds from more serious damage. Most significant changes of these “defense” parameters in case of multiple stressors suggest activation of this universal mechanism in situation with complex exposure and its crucial role in protection of the bird health in the environment. 相似文献
996.
Background
Recent guidance from related regulatory agencies and medical societies supports mandatory vaccination of healthcare workers (HCW) against influenza. At St. Jude Children's Research Hospital, a pediatric oncology referral center, more than 90% of HCWs receive vaccine each year without a policy mandating immunization. Factors associated with HCW uptake of influenza vaccines have not previously been evaluated in a high compliance rate setting.Methods
A structured, anonymous, electronic questionnaire was distributed in August 2010 to employees (HCW and non-HCW). Demographics, prior receipt of influenza vaccines, reasons for acceptance or refusal of seasonal and 2009 H1N1 pandemic vaccine, and attitudes on mandatory vaccination were assessed.Results
95.0% of 925 HCWs and 63.1% of all 3227 qualifying employees responded to the survey. 93.8% and 75.2% of HCW reported receiving seasonal and 2009 H1N1 influenza vaccines, respectively, in the 2009-2010 season. Benefits to self and/or patients were cited as the most frequent reasons for accepting seasonal (83.5% and 78.3%, respectively) and 2009 H1N1 (85.9% and 81.1%, respectively) vaccination. 36.6% of HCWs opposed mandating influenza vaccination; 88.2% and 59.9% of whom reported receiving the seasonal and 2009 H1N1 influenza vaccines, respectively. Violation of freedom of choice and personal autonomy were the most frequently reported reasons for opposition.Conclusion
In this cohort of HCWs with a high influenza vaccination rate, realistic assessments of the potential benefits of vaccination appear to have driven the choice to accept immunization. Despite this, mandating vaccination was viewed unfavorably by a significant minority of vaccinated individuals. Employee concerns over autonomy should be addressed as institutions transition to mandatory vaccination policies. 相似文献997.
Bernstein DI El Sahly HM Keitel WA Wolff M Simone G Segawa C Wong S Shelly D Young NS Dempsey W 《Vaccine》2011,29(43):7357-7363
Parvovirus B19 is an important human pathogen causing erythema infectiosum, transient aplastic crisis in individuals with underlying hemolytic disorders and hydropsfetalis. We therefore evaluated a parvovirus B19 virus like particle (VLP) vaccine. The safety and immunogenicity of a 25 μg dose of parvovirus B19 recombinant capsid; 2.5 and 25 μg doses of the recombinant capsid given with MF59; and saline placebo were assessed in healthy adults. Because of 3 unexplained cutaneous events the study was halted after enrollment of 43 subjects and before any subject received their third scheduled dose. The rashes developed 5-9 days after the first or second injection and were seen in one placebo recipient (without an injection site lesion) and two vaccine recipients (with injection site reactions). No clear cause was established. Other safety evaluations revealed mostly injection site reactions that were mild to moderate with an increase in pain in subjects receiving vaccine and MF59. After dose 2 the majority of vaccine recipients developed ELISA and neutralizing antibody to parvovirus B19. Given the possible severe consequences of parvovirus B19 infection, further development of a safe and effective vaccine continues to be important. 相似文献
998.
Adler-Moore J Munoz M Kim H Romero J Tumpey T Zeng H Petro C Ernst W Kosina S Jimenez G Fujii G 《Vaccine》2011,29(27):4460-4468
While the current influenza vaccine strategy is dependent on eliciting neutralizing antibodies to the hemagglutinin (H or HA) surface glycoprotein, antigenic drifts and occasional antigenic shifts necessitate constant surveillance and annual updates to the vaccine components. The ectodomain of the matrix 2 (M2e) channel protein has been proposed as a universal vaccine candidate, although it has not yet been shown to elicit neutralizing antibodies. Utilizing a liposome-based vaccine technology, an M2e vaccine (L-M2e-HD/MPL) was tested and shown to stimulate the production of anti-M2e antibodies which precipitated with whole virus and inhibited viral cell lysis by multiple type A strains of influenza virus using a novel in vitro assay. The anti-M2e antibodies also conferred complete protection following passive transfer from L-M2e-HD/MPL vaccinated mice to naïve mice challenged with H1N1 virus. Significantly higher levels of IL-4 compared to IFN-γ were secreted by the splenocytes of L-M2e-HD/MPL vaccinated mice incubated with M2e. In addition, depletion of CD4 cells or CD4 cells plus CD8 cells from L-M2e-HD/MPL vaccinated mice using monoclonal antibodies markedly decreased the level of protection of the vaccine when compared to just CD8 depletion of L-M2e-HD/MPL vaccinated mice. These results suggest that the protective immune response elicited by this vaccine is mediated primarily by a Th2 mechanism. 相似文献
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1000.
Rambousek L Bubenikova-Valesova V Kacer P Syslova K Kenney J Holubova K Najmanova V Zach P Svoboda J Stuchlik A Chodounska H Kapras V Adamusova E Borovska J Vyklicky L Vales K 《Neuropharmacology》2011,61(1-2):61-68
Preclinical studies have demonstrated a considerable role for N-methyl-d-aspartate (NMDA) receptors in excitotoxicity and the concurrent neuroprotective effect of NMDA receptor antagonists. Because NMDA receptors are one of the most widespread receptors in the central nervous system, application of their antagonist often leads to serious side effects ranging from motor impairment to induction of schizophrenic-like psychosis. Therefore, we have initiated development and testing of a novel synthetic NMDA receptor antagonist derived from naturally occurring neurosteroids. 20-oxo-5β-pregnan-3α-yl-l-glutamyl-1-ester (3α5βP-Glu) is a novel synthetic steroidal inhibitor of the NMDA receptor. Our results show that 3α5βP-Glu preferentially inhibits tonically activated NMDA receptors, is able to cross the blood brain barrier, does not induce psychotomimetic symptoms (such as hyperlocomotion and sensorimotor gating deficit) and reduced an excitotoxic damage of brain tissue and subsequent behavioural impairment in rats. In particular, 3α5βP-Glu significantly ameliorated neuronal damage in the dentate gyrus and subiculum, and improved behavioural performance in active allothetic place avoidance tasks (AAPA, also known as the carousel maze) after bilateral NMDA-induced lesions to the hippocampi. These findings provide a possible new therapeutic approach for the treatment of diseases induced by NMDA receptor overactivation. 相似文献