438 research outputs found
On the Concept of a Notational Variant
In the study of modal and nonclassical logics, translations have frequently been employed as a way of measuring the inferential capabilities of a logic. It is sometimes claimed that two logics are “notational variants” if they are translationally equivalent. However, we will show that this cannot be quite right, since first-order logic and propositional logic are translationally equivalent. Others have claimed that for two logics to be notational variants, they must at least be compositionally intertranslatable. The definition of compositionality these accounts use, however, is too strong, as the standard translation from modal logic to first-order logic is not compositional in this sense. In light of this, we will explore a weaker version of this notion that we will call schematicity and show that there is no schematic translation either from first-order logic to propositional logic or from intuitionistic logic to classical logic
Global metabolic analyses of acinetobacter baumannii
Acinetobacter baumannii is rapidly emerging as a multidrug-resistant pathogen responsible for nosocomial infections including pneumonia, bacteremia, wound infections, urinary tract infections, and meningitis. Metabolomics provides a powerful tool to gain a system-wide snapshot of cellular biochemical networks under defined conditions and has been increasingly applied to bacterial physiology and drug discovery. Here we describe an optimized sample preparation method for untargeted metabolomics studies in A. baumannii. Our method provides a significant recovery of intracellular metabolites to demonstrate substantial differences in global metabolic profiles among A. baumannii strains
Effect of the Japanese herbal medicine, Boiogito, on the osteoarthritis of the knee with joint effusion
<p>Abstract</p> <p>Background</p> <p>Boiogito (Japanese herbal medicine, Tsumura Co. Tokyo, Japan) contains <it>sinomenin </it>which inhibits inflammatory reactions. Since <it>sinomenine </it>is a principle component of the Boiogito, there is a possibility of it being effective on osteoarthritis (OA) of the knee with joint effusion. However, there is no report concerning the effectiveness of Boiogito on knee OA. The objective of the present study is to investigate the therapeutic effect of Boiogito on OA of the knee associated with joint effusion in a comparative study among randomly assigned groups.</p> <p>Methods</p> <p>Study was performed using 50 patients who were diagnosed with primary osteoarthritis of the knee with joint effusion. The patients were randomly assigned to two groups: one group (25 patients) using both loxoprofen (2-{4-[(2-oxocyclopentyl) methyl]} propanoic acid) and Boiogito and the other group (25 patients) using loxoprofen, and were evaluated during a 12 week observation period. The assessment parameters including knee scores in the Knee Society Rating System including Knee score and Functional scores, amount of joint effusion by joint puncture in clinically detected cases, the 36-items short form of the Medical Outcome Study Questionnaire (SF-36) as a measurement of health related quality of life were used.</p> <p>Results</p> <p>The knee scores based on the Knee Society Rating System were improved in both groups. The staircase climbing up and down ability in the Knee society rating system functional score was significantly improved in the group using Boiogito and loxoprofen compared to the loxoprofen group. In the evaluation using SF-36, significant improvements were found in the scores in both groups in physical functioning after 12 weeks. The amount of joint fluid was significantly decreased at 4, 8 and 12 weeks compared to pre-administration baseline in the group using Boiogito and loxoprofen. A side effect of Boiogito, dry mouth, was found in one case. The symptom was mild and improved immediately after discontinuation of administration.</p> <p>Conclusion</p> <p>The results indicated that Boiogito have a possibility for a treatment modality for joint effusion with osteoarthritis of the knee.</p
Malaria and Under-Nutrition: A Community Based Study Among Under-Five Children at Risk of Malaria, South-West Ethiopia
BACKGROUND: The interaction between malaria and under-nutrition is not well elucidated in Ethiopia. The objective of this study was to assess the magnitude of under-nutrition and its correlation with malaria among under-five children in south-west Ethiopia. METHODS: This cross-sectional study was undertaken during March-February, 2009 as part of the baseline assessment of a cluster randomized trial around Gilgel Gibe Hydroelectric dam, south-west Ethiopia. A total of 2410 under-five children were included for anthropometric measurement and blood investigation for the diagnosis of malaria and anemia. The nutritional status of children was determined using the International Reference Population defined by the U.S National Center for Health Statistics (NCHS). Blood film was used to identify malaria parasite and haemoglobin concentration was determined by Hemo Cue analyzer (HemoCue Hb 301, Sweden). RESULTS: Significant proportion (40.4%) of under-five children were stunted (height-for-age<-2SD). The prevalence of under-weight was 34.2%. One third and one tenth of the children had anemia and malaria parasite respectively. Older children were more likely to have under-nutrition. There was no association between malaria and under-nutrition. Children who had malaria parasite were 1.5 times more likely to become anaemic compare to children who had no malaria parasite, [OR = 1.5, (95% CI: 1.1-2.0)]. CONCLUSION: In this study, there is no association between malaria and under-nutrition. Children who have malaria are more likely to be anaemic. Malaria prevention and control program should consider nutrition interventions particularly anemia
Upregulation of MMP-13 and TIMP-1 expression in response to mechanical strain in MC3T3-E1 osteoblastic cells
<p>Abstract</p> <p>Background</p> <p>Mechanical strain plays a significant role in the regulation of bone matrix turnover, which is mediated in part by matrix metalloproteinase (MMP)-13 and tissue inhibitors of matrix metalloproteinase (TIMP)-1. However, little is known about the correlation between mechanical strain and osteoblastic cell activities, including extracellular matrix (ECM) metabolism. Herein, we determined the effect of different magnitudes of cyclic tensile strain (0%, 6%, 12%, and 18%) on MMP-13 and TIMP-1 mRNA and protein expression in MC3T3-E1 osteoblasts. Furthermore, we employed specific inhibitors to examine the role of distinct signal transduction pathways known to mediate cellular responses to mechanical strain.</p> <p>Results</p> <p>We identified a magnitude-dependent increase in MMP-13 and TIMP-1 mRNA and protein levels in response to mechanical strains corresponding to 6%, 12%, and 18% elongation. The strain-induced increases in MMP-13 and TIMP-1 mRNA expression were inhibited by PD098059 and cycloheximide, respectively.</p> <p>Conclusions</p> <p>Our results suggest a mechanism for the regulation of bone matrix metabolism mediated by the differential expression of MMP-13 and TIMP-1 in response to increasing magnitudes of mechanical strain.</p
Direct magnetic field detection in the innermost regions of an accretion disc
Models predict that magnetic fields play a crucial role in the physics of
astrophysical accretion disks and their associated winds and jets. For example,
the rotation of the disk twists around the rotation axis the initially vertical
magnetic field, which responds by slowing down the plasma in the disk and by
causing it to fall towards the central star. The magnetic energy flux produced
in this process points away from the disk, pushing the surface plasma outwards,
leading to a wind from the disk and sometimes a collimated jet. But these
predictions have hitherto not been supported by observations. Here we report
the direct detection of the magnetic field in the core of the protostellar
accretion disk FU Orionis. The surface field reaches strengths of about 1 kG
close to the centre of the disk, and it includes a significant azimuthal
component, in good agreement with recent models. But we find that the field is
very filamentary and slows down the disk plasma much more than models predict,
which may explain why FU Ori fails to collimate its wind into a jet.Comment: 11 pages, 3 figure
Household and community socioeconomic and environmental determinants of child nutritional status in Cameroon
BACKGROUND: Undernutrition is a leading cause of child mortality in developing countries, especially in sub-Saharan Africa. We examine the household and community level socioeconomic and environmental factors associated with child nutritional status in Cameroon, and changes in the effects of these factors during the 1990s economic crisis. We further consider age-specific effects of household economic status on child nutrition. METHODS: Child nutritional status was measured by weight-for-age (WAZ) and height-for-age (HAZ) z-scores. Data were from Demographic and Health Surveys conducted in 1991 and 1998. We used analysis of variance to assess the bivariate association between the explanatory factors and nutritional status. Multivariate, multilevel analyses were undertaken to estimate the net effects of both household and community factors. RESULTS: Average WAZ and HAZ declined respectively from -0.70 standard deviations (SD), i.e. 0.70 SD below the reference median, to -0.83 SD (p = 0.006) and from -1.03 SD to -1.14 SD (p = 0.026) between 1991 and 1998. These declines occurred mostly among boys, children over 12 months of age, and those of low socioeconomic status. Maternal education and maternal health seeking behavior were associated with better child nutrition. Household economic status had an overall positive effect that increased during the crisis, but it had little effect in children under 6 months of age. Improved household (water, sanitation and cooking fuel) and community environment had positive effects. Children living in the driest regions of the country were consistently worst off, and those in the largest cities were best off. CONCLUSION: Both household and community factors have significant impact on child health in Cameroon. Understanding these relationships can facilitate design of age- and community-specific intervention programs
Cytokine preconditioning of engineered cartilage provides protection against interleukin-1 insult
Research reported in this publication was supported in part by the National Institute of Arthritis and Musculoskeletal and Skin Diseases and National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health under Award Number R01AR60361, R01AR061988, P41EB002520). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. ART was supported by a National Science Foundation Graduate Fellowship
Prostate response to prolactin in sexually active male rats
BACKGROUND: The prostate is a key gland in the sexual physiology of male mammals. Its sensitivity to steroid hormones is widely known, but its response to prolactin is still poorly known. Previous studies have shown a correlation between sexual behaviour, prolactin release and prostate physiology. Thus, here we used the sexual behaviour of male rats as a model for studying this correlation. Hence, we developed experimental paradigms to determine the influence of prolactin on sexual behaviour and prostate organization of male rats. METHODS: In addition to sexual behaviour recordings, we developed the ELISA procedure to quantify the serum level of prolactin, and the hematoxilin-eosin technique for analysis of the histological organization of the prostate. Also, different experimental manipulations were carried out; they included pituitary grafts, and haloperidol and ovine prolactin treatments. Data were analyzed with a One way ANOVA followed by post hoc Dunnet test if required. RESULTS: Data showed that male prolactin has a basal level with two peaks at the light-dark-light transitions. Consecutive ejaculations increased serum prolactin after the first ejaculation, which reached the highest level after the second, and started to decrease after the third ejaculation. These normal levels of prolactin did not induce any change at the prostate tissue. However, treatments for constant elevations of serum prolactin decreased sexual potency and increased the weight of the gland, the alveoli area and the epithelial cell height. Treatments for transient elevation of serum prolactin did not affect the sexual behaviour of males, but triggered these significant effects mainly at the ventral prostate. CONCLUSION: The prostate is a sexual gland that responds to prolactin. Mating-induced prolactin release is required during sexual encounters to activate the epithelial cells in the gland. Here we saw a precise mechanism controlling the release of prolactin during ejaculations that avoid the detrimental effects produced by constant levels. However, we showed that minor elevations of prolactin which do not affect the sexual behaviour of males, produced significant changes at the prostate epithelium that could account for triggering the development of hyperplasia or cancer. Thus, it is suggested that minute elevations of serum prolactin in healthy subjects are at the etiology of prostate abnormal growth
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