47 resultados para 7-GC 6


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Background: It seems plausible that children with atopy and persistent asthma symptoms will, like their adult counterparts, have chronic airways inflammation. However, many young children with no other atopic features have episodic wheezing that is triggered solely by viral respiratory infections. Little is known as to whether airways inflammation occurs in these two asthma patterns during relatively asymptomatic periods.

Methods: Using a non-bronchoscopic bronchoalveolar lavage (BAL) procedure on children presenting for an elective surgical procedure, this study has investigated the cellular constituents of BAL fluid in children with a history of atopic asthma (AA) non-asthmatic atopic children (NAA) or viral associated wheeze (VAW).

Results: A total of 95 children was studied: 52 with atopic asthma (8.0 years, range 1.1-15.3, 36 male), 23 with non-asthmatic atopy (median age 8.3 years, range 1.7-13.6, 11 male) and 20 with VAW (3.1 years, range 1.0-8.2, 13 male). No complications were observed during the lavage procedure and no adverse events were noted post-operatively. Total lavage fluid recovered was similar in all groups and the total cell numbers were higher in the VAW group. Eosinophil (P< 0.005) and mast cell (/'<0.05) numbers were significantly elevated in the group with atopic asthma.

Conclusions: During relatively asymptomatic periods there is on-going airways inflammation, as demonstrated by eosinophil and mast cell recruitment, in children with asthma and atopy but not in children with viral associated wheeze or atopy alone. This strongly suggests that there are different underlying pathophysiologicai mechanisms in these two groups of children who wheeze.

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Substance P elicits histamine release from human skin and rodent mast cells. Since neuropeptide-mediated reflexes may be important in asthma, we examined the ability of substance P to stimulate human mast cells obtained at bronchoalveolar lavage (BAL). BAL samples were obtained at routine bronchoscopy from 35 non-preselected patients. Histamine release experiments were performed in a standard manner using substance P and the calcium ionophore A23187. Both substance P (50 μM) and A23187 caused histamine release (median 26.7%, range 6.2–62.8% and 32.1%, 7.7–56.8% respectively) which was significantly greater (P < 0.0001) than the spontaneous release (median 15.6%, range 4.1–33.4%), i.e. that in the absence of any stimulus. Substance P induced histamine release was via an energy dependent process and was blocked by preincubation with antimycin A. A significant correlation was observed between substance P induced release and spontaneous release but was not observed with A23187 induced release. Mast cell counts correlated significantly with substance P induced release but not with spontaneous or A23187 induced release. The substance P induced histamine secretion was elicited at similar concentrations to those used with rodent and human skin mast cells. Asthma is associated with increased numbers of mast cells which have both increased spontaneous and stimulated secretory responses. Thus, in vivo, the bronchoconstrictor action of substance P may in part result from activation of mast cells in the bronchial lumen.

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This Letter describes the synthesis and SAR of two mGluR4 positive allosteric modulator leads, 6 and 7. VU001171 (6) represents the most potent (EC50 = 650 nM), efficacious (141% Glu Max) and largest fold shift (36-fold) of any mGluR4 PAM reported to date. However, this work highlights the challenges in hit-to-lead for mGluR4 PAMs, with multiple confirmed HTS hits displaying little or no tractable SAR. (C) 2008 Elsevier Ltd. All rights reserved.

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Positive deviations from linear sea-level trends represent important climate signals if they are persistent and geographically widespread. This paper documents rapid sea-level rise reconstructed from sedimentary records obtained from salt marshes in the Southwest Pacific region (Tasmania and New Zealand). A new late Holocene relative sea-level record from eastern Tasmania was dated by AMS(14)C (conventional, high precision and bomb-spike), Cs-137, Pb-210, stable Pb isotopic ratios, trace metals, pollen and charcoal analyses. Palaeosea-level positions were determined by foraminiferal analyses. Relative sea level in Tasmania was within half a metre of present sea level for much of the last 6000 yr. Between 1900 and 1950 relative sea level rose at an average rate of 4.2 +/- 0.1 mm/yr. During the latter half of the 20th century the reconstructed rate of relative sea-level rise was 0.7 +/- 0.6 mm/yr. Our study is consistent with a similar pattern of relative sea-level change recently reconstructed for southern New Zealand. The change in the rate of sea-level rise in the SW Pacific during the early 20th century was larger than in the North Atlantic and could suggest that northern hemisphere land-based ice was the most significant melt source for global sea-level rise. (C) 2011 Elsevier B.V. All rights reserved.

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We report in this paper the computation of accurate total collision strengths and effective collision strengths for electron-impact excitation of FeII, using the parallel R-matrix program PRMAT. Target states corresponding to the 3d(6)4s, 3d(7), 3d(6)4p and 3d(5)4s4s basis configurations were included in the calculations giving rise to a 113 LS state 354 coupled channel problem. Following a detailed systematic study of correlation effects in both the target state and collision wavefunctions, it was found that an additional 21 configuration functions needed to be included in the Configuration Interaction expansion to obtain significantly more accurate target states and collision wavefunctions. This much improved 26-configuration model has been used to calculate converged total effective collision strengths for all sextet to quartet transitions among these levels with total spin S=2, giving a total of 1785 lines. These calculations have laid the foundation for an approach which may be adopted in the study of electron collisions with the low ionization stages of other iron peak elements. The work has been further extended with the commencement of a Breit-Pauli relativistic calculation for one of the smaller models and includes 262 fine-structure levels and over 1800 coupled channels. At the same time the PRMAT parallel R-matrix package is being extended to include relativistic effects which will allow us to attempt the more sophisticated 26-configuration model and produce for the first time the amount and quality of atomic data required to perform a meaningful synthesis of the Fe II spectrum.

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Essential genes are absolutely required for the survival of an organism. The identification of essential genes, besides being one of the most fundamental questions in biology, is also of interest for the emerging science of synthetic biology and for the development of novel antimicrobials. New antimicrobial therapies are desperately needed to treat multidrug-resistant pathogens, such as members of the Burkholderia cepacia complex.

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Although coordinated patterns of body movement can be used to communicate action intention, they can also be used to deceive. Often known as deceptive movements, these unpredictable patterns of body movement can give a competitive advantage to an attacker when trying to outwit a defender. In this particular study, we immersed novice and expert rugby players in an interactive virtual rugby environment to understand how the dynamics of deceptive body movement influence a defending player’s decisions about how and when to act. When asked to judge final running direction, expert players who were found to tune into prospective tau-based information specified in the dynamics of ‘honest’ movement signals (Centre of Mass), performed significantly better than novices who tuned into the dynamics of ‘deceptive’ movement signals (upper trunk yaw and out-foot placement) (p<.001). These findings were further corroborated in a second experiment where players were able to move as if to intercept or ‘tackle’ the virtual attacker. An analysis of action responses showed that experts waited significantly longer before initiating movement (p<.001). By waiting longer and picking up more information that would inform about future running direction these experts made significantly fewer errors (p<.05). In this paper we not only present a mathematical model that describes how deception in body-based movement is detected, but we also show how perceptual expertise is manifested in action expertise. We conclude that being able to tune into the ‘honest’ information specifying true running action intention gives a strong competitive advantage.

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The texts adapted for, printed for and marketed to children and youths in the 16th and 17th centuries, the books read by boys and girls in this period, and writings by Renaissance children constitute the literature of early modern childhoods. Yet traditional histories of children’s literature, posing narrow definitions of this genre, have largely overlooked this period. In the past decade, fresh work by early modern scholars attending to the diverse elements of the literature of early modern childhoods has flourished. This essay evaluates the absence of early modern children’s literature from early studies and considers the ways in which this recent work in Renaissance studies has vitally transformed the field through its exploration of alternative definitions of childhood and children’s literature. This work is at an early stage but it has placed the interconnections between early modern childhoods and children’s literature at the centre of both Renaissance studies and childhood studies and has established key topics for future research.

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Cathepsin L proteases secreted by the helminth pathogen Fasciola hepatica have functions in parasite virulence including tissue invasion and suppression of host immune responses. Using proteomics methods alongside phylogenetic studies we characterized the profile of cathepsin L proteases secreted by adult F. hepatica and hence identified those involved in host-pathogen interaction. Phylogenetic analyses showed that the Fasciola cathepsin L gene family expanded by a series of gene duplications followed by divergence that gave rise to three clades associated with mature adult worms (Clades 1, 2, and 5) and two clades specific to infective juvenile stages (Clades 3 and 4). Consistent with these observations our proteomics studies identified representatives from Clades 1, 2, and 5 but not from Clades 3 and 4 in adult F. hepatica secretory products. Clades 1 and 2 account for 67.39 and 27.63% of total secreted cathepsin Ls, respectively, suggesting that their expansion was positively driven and that these proteases are most critical for parasite survival and adaptation. Sequence comparison studies revealed that the expansion of cathepsin Ls by gene duplication was followed by residue changes in the S2 pocket of the active site. Our biochemical studies showed that these changes result in alterations in substrate binding and suggested that the divergence of the cathepsin L family produced a repertoire of enzymes with overlapping and complementary substrate specificities that could cleave host macromolecules more efficiently. Although the cathepsin Ls are produced as zymogens containing a prosegment and mature domain, all secreted enzymes identified by MS were processed to mature active enzymes. The prosegment region was highly conserved between the clades except at the boundary of prosegment and mature enzyme. Despite the lack of conservation at this section, sites for exogenous cleavage by asparaginyl endopeptidases and a Leu-Ser[downward arrow]His motif for autocatalytic cleavage by cathepsin Ls were preserved.

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Rhizosphere microorganisms play an important role in soil carbon flow, through turnover of root exudates, but there is little information on which organisms are actively involved or on the influence of environmental conditions on active communities. In this study, a (CO2)-C-13 pulse labelling field experiment was performed in an upland grassland soil, followed by RNA-stable isotope probing (SIP) analysis, to determine the effect of liming on the structure of the rhizosphere microbial community metabolizing root exudates. The lower limit of detection for SIP was determined in soil samples inoculated with a range of concentrations of C-13-labelled Pseudomonas fluorescens and was found to lie between 10(5) and 10(6) cells per gram of soil. The technique was capable of detecting microbial communities actively assimilating root exudates derived from recent photo-assimilate in the field. Denaturing gradient gel electrophoresis (DGGE) profiles of bacteria, archaea and fungi derived from fractions obtained from caesium trifluoroacetate (CsTFA) density gradient ultracentrifugation indicated that active communities in limed soils were more complex than those in unlimed soils and were more active in utilization of recently exuded C-13 compounds. In limed soils, the majority of the community detected by standard RNA-DGGE analysis appeared to be utilizing root exudates. In unlimed soils, DGGE profiles from C-12 and C-13 RNA fractions differed, suggesting that a proportion of the active community was utilizing other sources of organic carbon. These differences may reflect differences in the amount of root exudation under the different conditions.

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Procedural pain is associated with poorer neurodevelopment in infants born very preterm (= 32 weeks gestational age), however, the etiology is unclear. Animal studies have demonstrated that early environmental stress leads to slower postnatal growth; however, it is unknown whether neonatal pain-related stress affects postnatal growth in infants born very preterm. The aim of this study was to examine whether greater neonatal pain (number of skin-breaking procedures adjusted for medical confounders) is related to decreased postnatal growth (weight and head circumference [HC] percentiles) early in life and at term-equivalent age in infants born very preterm. Participants were n=78 preterm infants born = 32 weeks gestational age, followed prospectively since birth. Infants were weighed and HC measured at birth, early in life (median: 32 weeks [interquartile range 30.7-33.6]) and at term-equivalent age (40 weeks [interquartile range 38.6-42.6]). Weight and HC percentiles were computed from sex-specific British Columbia population-based data. Greater neonatal pain predicted lower body weight (Wald ?(2)=7.36, P=0.01) and HC (Wald ?(2)=4.36, P=0.04) percentiles at 32 weeks postconceptional age, after adjusting for birth weight percentile and postnatal risk factors of illness severity, duration of mechanical ventilation, infection, and morphine and corticosteroid exposure. However, later neonatal infection predicted lower weight percentile at term (Wald ?(2)=5.09, P=0.02). Infants born very preterm undergo repetitive procedural pain during a period of physiological immaturity that appears to impact postnatal growth, and may activate a downstream cascade of stress signaling that affects later growth in the neonatal intensive care unit.

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Background: The self-reported use of natural health products (NHPs) (herbal products and vitamin and mineral supplements) has increased over the past decade in Canada. Because the elderly population might have comorbidities and concurrently administered medications, there is a need to explore the perceptions and behaviors associated with NHPs in this age group. Objective: The goal of this study was to assess the use of NHPs in a cohort of older Canadian residents and the characteristics, perceptions, and behaviors associated with NHP use. Methods: Survey participants aged =60 years were randomly selected from telephone listings in the area of greater Hamilton, Ontario, Canada. Data were collected using a standardized computer-assisted telephone interview system. Self-reported data covering 7 domains were collected: (1) demographics; (2) self-reported 12-month NHP use; (3) reasons for NHP use; (4) self-reported 12-month prescription medication use; (5) expenditures on NHPs; (6) patient-reported adverse events and drug-NHP interactions; and (7) perceptions of physicians' attitudes regarding NHPs. Descriptive statistics were used to compare the characteristics of NHP users with those of nonusers and to assess the characteristics of NHP users across these 7 domains. Multivariate regression analysis was conducted to determine the demographic variables that might be associated with NHP user status. Results: Of 2528 persons identified as age =60 years, 1206 (48%) completed the telephone interview. Six hundred sixteen of these respondents (51%) reported the use of =1 NHP during the previous 12 months. On the initial univariate analysis, younger age and higher income were significantly associated with reporting NHP use (mean age, users vs nonusers, 71.1 vs 72.7 years, respectively; 95% CI, 1.02-1.06; P <0.001; income more than Can $26,000 was 28% and 22% in users and nonusers, respectively; P = 0.028). One hundred seventy of 616 users (28%) used an NHP to treat the same condition for which they were concurrently receiving a prescription medication, and 43 (25%) had not informed their physicians about their NHP use. Patients' characteristics such as sex, education, smoking status, and self-reported health status did not differ significantly between users and nonusers. In individuals who regularly spent money to purchase NHPs (n = 394), the mean cost was $20.38/mo. NHP expenditure was not significantly associated with age, sex, or income. Conclusion: Based on these findings, a substantial proportion of those Ontarians aged =60 years reported NHP use, and there is a need for greater communication with physicians to avoid potential drug-NHP interactions. © 2009 Excerpta Medica Inc. All rights reserved.

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PURPOSE:
The protease inhibitor bortezomib attenuates the action of NF-κB and has shown preclinical activity alone and in combination with chemotherapy.

DESIGN:
A Phase I dose-escalation study was performed administering bortezomib (0.7, 1.0, 1.3 and 1.6 mg m(-2) on days 1 and 8 from cycle 2 onwards) in combination with Epirubicin 50 mg m(-2) intravenously on day 1, Carboplatin AUC 5 day 1 and Capecitabine 625 mg m(-2) BD days 1-21 every 21 days (VECarboX regimen), in patients with advanced oesophagogastric adenocarcinoma. The primary objective was to define the maximum tolerated dose (MTD) of Bortezomib when combined with ECarboX.

RESULTS:
18 patients received bortezomib 0.7 (n = 6), 1.0 (n = 3), 1.3 (n = 6) and 1.6 mg m(-2) (n = 3) and a protocol amendment reducing the capecitabine dose to 500 mg m(-2) BD was enacted due to myelotoxicity. Common treatment-related non-haematological adverse events of any grade were fatigue (83.3 %), anorexia (55.6 %), constipation (55.6 %) and nausea (55.6 %). Common Grade 3/4 haematological toxicities were neutropenia (77.8 %) and thrombocytopenia (44.4 %). Objective responses were achieved in 6 patients (33.3 %) and a further 5 patients (27.8 %) had stable disease for >8 weeks.

CONCLUSIONS:
The addition of Bortezomib to ECarboX is well tolerated and response rates are comparable with standard chemotherapy.

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BACKGROUND AND OBJECTIVE: To determine the frequency of encapsulated blebs after guarded filtration procedures with mitomycin-C. PATIENTS AND METHODS: The authors reviewed the charts of all patients who had undergone a guarded filtration procedure with mitomycin-C. There were 235 patients (283 cases) who had more than 1 month of follow-up. RESULTS: An encapsulated bleb developed in 7 eyes (2.47%) of 6 patients. Identification of bleb encapsulation occurred at a mean follow-up time of 29.7 ± 14.6 days after surgery. The mean intraocular pressure at that point was 24.2 ± 13.5 mm Hg in the affected eyes. Three eyes were treated medically, and needling was performed in 4 eyes. CONCLUSION: There is a low frequency of encapsulated bleb formation after guarded filtration procedures with adjunctive mitomycin- C.