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Insignificant Reductions (insignificant + reduction)
Selected AbstractsResearch to practice: Effectiveness of controlled workplace interventions to reduce musculoskeletal disorders in the manufacturing environment,critical appraisal and meta-analysisHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2008Setenay Tuncel Previous studies on the effectiveness of interventions in reducing musculoskeletal disorders (MSD) in manufacturing facilities had contradictory results, indicating a need for a quality assessment of these studies followed by a quantitative assessment of the overall effectiveness of the interventions. These assessments may also provide suggestions for practical implementations. The first objective of this study is to assess the effectiveness of controlled workplace interventions to reduce the occurrence of MSD in the manufacturing environment by utilizing meta-analysis integrated with the study quality score. The second objective is to translate the research findings into practical guidelines. Two hypotheses were tested pertinent to the first objective: (1) Controlled workplace interventions are effective in reducing the occurrence of MSD in different body regions among manufacturing workers and (2) the study quality scores do not depend on the evaluator. The study quality was assessed for all articles, however, meta effect size (meta-OR) was calculated only for the articles that reported prevalence of low back disorders (LBDs), using the Mantel,Haenszel method. The effect of study quality was included into meta-OR. The chi-square test of independence was employed to test the second hypothesis. Seven articles were identified. Study quality was poor (0.39 out of 2) to moderate (0.97). Insignificant reduction in LBDs prevalence (meta-OR = 0.925; 95% CI: 0.566,1.512) was found. Integration of the study quality did not have a substantial effect on the meta-OR (meta-OR = 0.933; 95% CI: 0.571,1.525). Each evaluator's study quality scores were not independent from the agreed quality scores (p < 0.01). The results suggested that practitioners should consider scientific evidence during design and implementation of an intervention, especially in terms of study duration, confounders, outcome measures, and data analysis. The articles reviewed exhibited the following: (1) the statistical insignificance of the meta-OR; (2) the relatively low methodological quality of studies; and (3) the small number of studies included in the meta-OR. The extent of the generalizability of meta-OR for LBD to other body regions was also in question. Future research should consider the following: (1) the physical and nonphysical work environment should be assessed to determine the workplace-specific needs, and the intervention should be structured around these needs; (2) group comparability, participation rate, subject loss, and randomization of subjects should be taken into account; (3) exposure and outcome measurement methods should be reported, as well as blinding of the observers and subjects, when applicable, to ensure reliability and validity; and (4) data analysis should be conducted adjusting for covariates and confounders, different lengths of follow-up, and level of exposure. © 2008 Wiley Periodicals, Inc. [source] The regulation of osteogenesis by ECM rigidity in MC3T3-E1 cells requires MAPK activationJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2007Chirag B. Khatiwala Once thought to provide only structural support to tissues by acting as a scaffold to which cells bind, it is now widely recognized that the extracellular matrix (ECM) provides instructive signals that dictate cell behavior. Recently we demonstrated that mechanical cues intrinsic to the ECM directly regulate the behavior of pre-osteoblastic MC3T3-E1 cells. We hypothesized that one possible mechanism by which ECM compliance exerts its influence on osteogenesis is by modulating the mitogen-activated protein kinase (MAPK) pathway. To address this hypothesis, the differentiation of MC3T3-E1 cells cultured on poly(ethylene glycol) (PEG)-based model substrates with tunable mechanical properties was assessed. Alkaline phosphatase (ALP) levels at days 7 and 14 were found to be significantly higher in cells grown on stiffer substrates (423.9 kPa hydrogels and rigid tissue culture polystyrene (TCPS) control) than on a soft hydrogel (13.7 kPa). Osteocalcin (OCN) and bone sialoprotein (BSP) gene expression levels followed a similar trend. In parallel, MAPK activity was significantly higher in cells cultured on stiffer substrates at both time points. Inhibiting this activation pharmacologically, using PD98059, resulted in significantly lower ALP levels, OCN, and BSP gene expression levels on the hydrogels. Interestingly, the effectiveness of PD98059 was itself dependent on substrate stiffness, with marked inhibition of MAPK phosphorylation in cells grown on compliant hydrogels but insignificant reduction in cells grown on TCPS. Together, these data confirm a role for MAPK in the regulation of osteogenic differentiation by ECM compliance. J. Cell. Physiol. 211: 661,672, 2007. © 2007 Wiley-Liss, Inc. [source] Morphological alterations in the amygdala and hippocampus of mice during ageingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2002Oliver Von Bohlen und Halbach Abstract Declines in memory function and behavioural dysfunction accompany normal ageing in mammals. However, the cellular and morphological basis of this decline remains largely unknown. It was assumed for a long time that cell losses in the hippocampus accompany ageing. However, recent stereological studies have questioned this finding. In addition, the effect of ageing is largely unknown in another key structure of the memory system, the amygdala. In the present study, we have estimated neuronal density and total neuronal numbers as well as density of fragments of degenerated axons in different hippocampal subfields and amygdaloid nuclei. Comparisons were made among aged (21,26 months old) mice and normal adult littermates (8 months old). No significant volume loss occurs in the hippocampus of aged mice. Small but insignificant reductions in total neuronal numbers were found in the hippocampus and in the amygdaloid nuclei. In contrast to the mild effects of ageing upon neuronal numbers, fragments of degenerated axons were increased in both hippocampus and amygdala of aged mice. These data suggest that ageing does not induce prominent cell loss in the hippocampus or amygdala, but leads to degeneration of axons that innervate these forebrain structures. Thus, mechanisms underlying age-related dysfunction depend on parameters other than neuronal numbers, at least in the hippocampal formation and the amygdala. [source] Effect of Combined Ozone and Organic Acid Treatment for Control of Escherichia coli O157:H7 and Listeria monocytogenes on LettuceJOURNAL OF FOOD SCIENCE, Issue 3 2006Hyun-Gyun Yuk ABSTRACT: This study was conducted to determine the effects of ozonated water (1, 3, and 5 ppm) alone with different exposure times (0.5,1,3, or5min), and combinations of 3 ppm ozone with 1% organic acids (acetic, citric, or lactic acids) during 1-min exposure for inactivating Escherichia coli O157:H7 and Listeria monocytogenes on lettuce and to observe the regrowth of these pathogenic bacteria on treated lettuce during storage for 10 d at 15°C. Results showed that 5 ppm ozone treatment for 5 min gave 1.09-log and 0.94-log reductions of E. coli O157:H7 and L. monocytogenes, respectively, indicating insignificant reductions compared with 3 ppm ozone treatment for 5 min. Treatment with 3 ppm ozone combined with 1 % citric acid for 1 min immersing resulted in 2.31 - and 1.84-log reductions (P < 0.05), respectively. During storage at 15°C for 10 d after combined treatment and packaging, populations of E. coli O157:H7 and L. monocytogenes increased to approximately 9.0-log colony forming unit (CFU) /g, indicating that this treatment did not have a residual antimicrobial effect during storage. Although the storage study did not show control of these pathogens, the combined ozone-organic acid treatment was more effective in reducing population levels of these pathogens on lettuce than individual treatments. [source] | ||||||||||