534 research outputs found
Antioxidative action of manganese treatment in delayed healing of acetic acid-induced ulceration in rat stomach
Background: The role of manganese in disease treatment such as diabetes, arthritis and osteoporosis has been well documented. Unhealed or delayed gastric ulcer is an experimental model mimicking recurrent peptic ulcer of which information is lacking. This study sought to examine the role of manganese during delayed gastric ulcer healing and its probable mechanism. Methods: 75 male wistar rats (150-170g) were divided into 5 groups of 15 rats each; Groups 1 was delayed untreated ulcerated animals while II, III, IV and V received 100mg/kg Manganese, 50mg/kg Manganese, 40 mg/kg Cimetidine and 100mg/kg Vitamin E respectively. Ulcer was induced by serosa application of 30% acetic acid and by day 5 post-induction, ulcer was delayed by continuous subcutaneous administration of 2mg/kg indomethacin (once daily) for 14 days simultaneously. Body weights of experimental animals were monitored daily, haematological studies; stomach ulcer score, biochemical and histological analysis were assessed by days 3, 7 and 14 indomethacin and drug treatment after quick decapitation. Data were expressed as Mean + SEM, analysed using one-way ANOVA while p=0.05 was considered statistically significant. Results: The percentage healing rates in Manganese (50mg/kg and 100mg/kg respectively) significantly increased on days 3 (76.5% and 42.9%), 7 (97.3% and 75.5%) and 14 (100% and 97.5%). Haematological data revealed increased circulating blood cells in the Manganese and Vitamin E treated groups compared with ulcerated untreated groups. Manganese treatment reduced gastric inflammation and lipid peroxidation (malodiadehyde, MDA) with a concomitant increase in superoxide dismutase and nitric oxide levels of gastric tissue homogenate compared with other treatment groups. Histological evaluations of gastric tissue from the manganese treated groups revealed healing compared with other treatment groups which further buttressed biochemical analysis. Conclusion: Manganese probably exerts its gastro-protective property on delayed ulcer by promoting increased antioxidant levels in experimental animals which probably mitigated the effect of continuous indomethacin injection.Keywords:Â Manganese, delayed ulcers, anti-inflammatory and antioxidative activitie
An inhomogeneous toy-model of the quantum gravity with explicitly evolvable observables
An inhomogeneous (1+1)-dimensional model of the quantum gravity is
considered. It is found, that this model corresponds to a string propagating
against some curved background space. The quantization scheme including the
Wheeler-DeWitt equation and the "particle on a sphere" type of the gauge
condition is suggested. In the quantization scheme considered, the "problem of
time" is solved by building of the quasi-Heisenberg operators acting in a space
of solutions of the Wheeler-DeWitt equation and the normalization of the wave
function corresponds to the Klein-Gordon type. To analyze the physical
consequences of the scheme, a (1+1)-dimensional background space is considered
for which a classical solution is found and quantized. The obtained estimations
show the way to solution of the cosmological constant problem, which consists
in compensation of the zero-point oscillations of the matter fields by the
quantum oscillations of the scale factor. Along with such a compensation, a
slow global evolution of a background corresponding to an universe expansion
exists.Comment: 18 page
Ocean stratification and low melt rates at the Ross Ice Shelf grounding zone
Oceanâdriven melting of ice shelves is a primary mechanism for ice loss from Antarctica. However, due to the difficulty in accessing the subâice shelf ocean cavity, the relationship between ice shelf melting and ocean conditions is poorly understood, particularly near the grounding zone, where the ice transitions from grounded to floating. We present the first borehole oceanographic observations from the grounding zone of the Ross Ice Shelf, Antarctica's largest ice shelf by area. Contrary to predictions that tidal currents near grounding zones mix the water column, we found that Ross Ice Shelf waters were vertically stratified. Current velocities at middepth in the ocean cavity did not change significantly over measurement periods at two different parts of the tidal cycle. The observed stratification resulted in low melt rates near this portion of the grounding zone, inferred from phaseâsensitive radar observations. These melt rates were generally <10 cm/year, which is lower than average for the Ross Ice Shelf (âŒ20 cm/year). Melt rates may be higher at portions of the grounding zone that experience higher subglacial discharge or stronger tidal mixing. Stratification in the cavity at the borehole site was prone to diffusive convection as a result of ice shelf melting. Since diffusive convection influences vertical heat and salt fluxes differently than shearâdriven turbulence, this process may affect ice shelf melting and merits further consideration in ocean models of subâice shelf circulation
Experiences of using the Theoretical Domains Framework across diverse clinical environments: a qualitative study
Background: The Theoretical Domains Framework (TDF) is an integrative framework developed from a synthesis of psychological theories as a vehicle to help apply theoretical approaches to interventions aimed at behavior change.
Purpose: This study explores experiences of TDF use by professionals from multiple disciplines across diverse clinical settings.
Methods: Mixed methods were used to examine experiences, attitudes, and perspectives of health professionals in using the TDF in health care implementation projects. Individual interviews were conducted with ten health care professionals from six disciplines who used the TDF in implementation projects. Deductive content and thematic analysis were used.
Results: Three main themes and associated subthemes were identified including: 1) reasons for use of the TDF (increased confidence, broader perspective, and theoretical underpinnings); 2) challenges using the TDF (time and resources, operationalization of the TDF) and; 3) future use of the TDF.
Conclusion: The TDF provided a useful, flexible framework for a diverse group of health professionals working across different clinical settings for the assessment of barriers and targeting resources to influence behavior change for implementation projects. The development of practical tools and training or support is likely to aid the utility of TDF
Soil stabilization with lime for the construction of forest roads
The mechanical performance of soil stabilization using lime to improve forest roads was assessed. This study was conducted with lateritic soil (LVAd30) using lime content of 2% in the municipality of NiquelĂąndia, GoiĂĄs state, Brazil. Geotechnical tests of soil characterization, compaction, and mechanical strength were performed applying different compaction efforts and curing periods. The results showed that lime content significantly changed the mechanical performance of natural soil, increasing its mechanical strength and load-carrying capacity. Compaction effort and curing time provided different responses in the unconfined compressive strength (UCS) and California Bearing Ratio (CBR) tests. The best UCS value (786.59 kPa) for the soil-lime mixture was achieved with modified compaction effort and curing time of 28 days. In the CBR test, soil-lime mixtures compacted at intermediate and modified efforts and cured for 28 days were considered for application as subbase material of flexible road pavements, being a promising alternative for use in layers of forest roads
A retrospective population based trend analysis on hospital admissions for lower respiratory illness among Swedish children from 1987 to 2000
BACKGROUND: Data relating to hospital admissions of very young children for wheezing illness have been conflicting. Our primary aim was to assess whether a previous increase in hospital admissions for lower respiratory illness had continued in young Swedish children. We have included re-admissions in our analyses in order to evaluate the burden of lower respiratory illness in very young children. We have also assessed whether changes in the labelling of symptoms have affected the time trend. METHODS: A retrospective, population based study was conducted to assess the time trend in admissions and re-admissions for lower respiratory illness. Data were obtained from the Swedish Hospital Discharge Register for all children with a first hospital admission before nine years of age, a total of 109,176 children. The register covers more than 98% of all hospital admissions in Sweden. The coding of diagnoses was based on ICD-9 from 1987 to 1996 and ICD-10 from 1997. RESULTS: The first admission rates declined significantly in children with a first admission after two years of age. However, an increasing admission trend was observed in children aged less than one year and 35% of first admissions occurred in this age group. The annual increase was 3.8% (95% CI 1.3â6.3) in boys and 5.0% (95% CI 2.4â7.6) in girls. A diagnostic shift appeared to occur when ICD-10 was introduced in 1997. The asthma and pneumonia admission rate in children aged less than one year levelled off, whereas the increase in admissions for bronchitis continued. The re-admission rates for asthma decreased and the probability of re-admission was higher in boys. National drug statistics demonstrated a substantial increase in the delivery of inhaled steroids to all age groups but most prescriptions occurred to children aged one year or more. CONCLUSION: Hospital admissions for lower respiratory illness are still increasing in children aged <1 year. Our findings are in line with other recent studies suggesting a change in the responsiveness to viral infections in very young children, but changes in admission criteria cannot be excluded. An increased use of inhaled steroids may have contributed to decreasing re-admission rates
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