583 research outputs found
Enhanced recovery and molecular techniques for determining bacterial colonists and viable pathogens on the complex phylloplane matrix
The rise in demand for fresh fruits and vegetables has seen an increase in the risk of gastrointestinal disease, by pathogens such as E. coli O157:H7 and Salmonella enterica, since such produce is eaten uncooked. Although most produce is washed in chlorinated water, this processing may not be sufficient and can result in the formation of hazardous compounds. Classical cell culture techniques as well as novel episcopic differential contrast and epifluorescence microscopy (EDIC/EF) combined with the BacLightTM kit (to distinguish live and dead bacteria), the DAPI assay (to distinguish bacterial colonists and inorganic debris) and GFP-Salmonella strains were combined for the first time to study the complex leaf surface (phylloplane). EDIC/EF microscopy was shown to be advantageous compared to other methodologies; as well as being able to visualize GFP-labelled Salmonella inoculated onto the phylloplane it was possible to observe the naturally residing microflora on this difficult matrix. The viable pathogens and microflora were shown to colonize by four strategies: they form clusters on the phylloplane; or single cells integrate into pre-existing aggregates of biofilm microcolonies; they become entrapped in niches such as stomata; or they actively swim into the stomata and become subsurface (confirmed using laser scanning confocal microscopy, LSCM). The clusters were sometimes surrounded by slime, suggesting the formation of biofilm on the phylloplane. The effects of treatments to the phylloplane were not directly comparable, due to large biological variations in each field of view; smaller treated sample areas should allow for qualitative and quantitative comparisons. The Stomacher is at present used worldwide for the mechanical release of microorganisms from various matrices; here it was compared to the Pulsifier, which was shown to be more efficient in terms of cell recovery and causing less damage to the watercress phylloplane. Surface attachment was investigated by use of the Pulsifier release principle and refinements in its protocol were made. Pulsifier recovery techniques showed the inefficiencies of potential disinfectants in killing attached microorganisms, since they were not susceptible to attack until released into aqueous suspension. It is these ‘protected’ cells that then subsequently go on to produce foodborne illnesses. Further study showed the molecular signalling molecule nitric oxide (NO), to be an important physiological release agent, for enhanced recovery of coliforms, but not Salmonella, from the phylloplane. Chemical methods of decontamination such as the use of ozone were shown to be efficient at reducing the numbers of viable cells, particularly when combined with pulsification mechanical release of cells into aqueous suspension, resulting in between 1- and 2-log reductions. However, this procedure is not ideal, due to chemical damage to the phylloplane and problems in maintaining constant ozone concentrations, both in the laboratory and at the factory. It was shown that chlorine levels could be reduced to 20 ppm compared to the industry standard of 90-120 ppm, this producing similar log reductions of between 1- and 2-log. The Pulsifier and NO were shown in combination to provide effective mechanical and physiological detachment strategies, releasing almost 4-log cells. It was found that 20 or 500 nM of NO, produced a 3-log dispersion of bacterial cells, including biofilm aggregates off the surface of watercress leaves. These studies demonstrate the importance of microbial physiology in the attachment of microorganisms on fresh produce phylloplanes and suggest that disinfection procedures are unnecessary for sanitation
Preparation for practice : an exploration of medical students' preparedness for professional practice
How well new medical school graduates are prepared to begin their first post as a doctor has received much focus in medical education. Research has indicated that new graduates can often feel unprepared for professional practice. This has subsequently informed the structure of policy documents on undergraduate course structure from the General Medical Council, with emphasis of structuring placements – student assistantships – where final year students take on some responsibilities of first year post-graduation doctors. A multiple methods study was performed at a medicalschool in the United Kingdom. Its aim was to explore preparedness of final year medical students with particular focus looking at experience gained during these student assistantship placements. Quantitative methodology was used with a survey undertaken looking at clinical skills gained by final year medical students. A qualitative study was performed with focus groups with students and newly graduated doctors; and face to face individual interviews with representatives from groups of senior professional doctors: placement supervisors, representatives of stakeholders of undergraduate and postgraduate education; and representatives with senior positions in NHS Trusts. Involving these multiple participants allowed exploration of preparation both as a quantifiable phenomenon of measurable skills and outcomes and also in gaining insight and understanding intopreparedness by considering the social structure around the student and the new doctor. Bourdieu's concepts of field, habitus and capital - from his theory of practice - were used to contextualise the findings and help present the complex concept of preparedness incorporating both the individual learner factors and the environment around them. This approach identified how preparation was not only influenced by what knowledge and clinical skills students and new doctors had achieved but also how it was influenced by changes to workplace like team structure, reconfiguration of training, and differing expectations of new doctors
The Association Between Older Age, Co-Morbidity, and Treatment Status of Incident Osteoporotic Fractures: A Population-Based Nested Cohort Study
I attended and presented a poster at the International Symposium on Osteoporosis hosted by the National Osteoporosis Foundation in Las Vegas, NV. This was a very well attended conference with over 800 attendees including clinicians and researchers interested / working in the area of osteoporosis. The research I presented was well received and added to the body of knowledge related to osteoporosis and treatment of new fractures. Attending this conference allowed me to meet other researchers with similar research interests and I look forward to possible collaborations in the future.BACKGROUND: Despite strong evidence-based rationale for both the primary and secondary prevention of osteoporosis, there remains an overall low prevalence of osteoporosis treatment in older adults. Furthermore, there is some question whether low treatment rates in older adults are simply age related variations (in treatments) or due to the presence of co-morbid conditions. Therefore, we sought to examine the association between older age, co-morbidity, and the use of osteoporosis medications following an incident osteoporosis related fracture.
METHODS: We performed a retrospective nested cohort analysis using de-identified administrative healthcare data from the province of British Columbia, Canada (pop. 4.1 million). We included patients 65 years and older, who had continuous enrollment in the provinces’ prescription drug plan, with a study-defined osteoporosis-related fracture during the study period of April 1, 1999 to March 31, 2002. A multivariate logistic regression model was used to examine the association between the dependent variable - osteoporosis medication dispensation within six months of index fracture and the predictor variables - age, sex, co-morbidity, fracture site, year of fracture, health region, and osteoporosis treatment prior to the index fracture.
RESULTS: After exclusion criteria were applied, we identified 11,870 consecutive patients who had been hospitalized with 12,025 incident (study-defined) fractures during the study period. The mean age of the sample was 81.1 years (SD 7.7; range 65–104 years), and 74% of the subjects were women. The majority of patients (99%) sustained one fracture (range 1 to 4); the fractures were predominately of the hip (63%) followed by fractures of the wrist (17%), pelvis (9%), vertebra (7%), and ribs (4%). The majority of subjects had no co-morbid conditions or only one (63%); 31% had two to three co-morbidities, and 6% had four or more co-morbid conditions. Overall, there was a low rate of osteoporosis treatment before the incident fracture (15% treatment); this rate improved to 19% at six months post fracture. Those receiving treatment after the index fracture were significantly younger, more often female, and had fewer co-morbid conditions (P < .001). The use of an osteoporosis medication prior to the index fracture was the strongest predictor of post-fracture treatment (adjusted OR = 15.89; 95% CI = 9.69–26.04). Increasing age, more than one co-morbid condition, and male sex were all associated with a significant decrease in the likelihood of dispensing osteoporosis drugs when compared to younger and healthier women.
CONCLUSION: Despite the wide availability of osteoporosis medications, our findings suggest that the majority of older adults, many of who have at least one co-morbid condition, are not receiving treatment to prevent the progression of the disease and to prevent further fractures
Valuing Ecosystem Goods and Services in the Columbia River Basin
The values presented in this report apply to the Columbia River Basin (CRB) in the US as a whole. While further work will be needed to estimate the values directly associated with the Columbia River Treaty (CRT), our analysis clearly demonstrates the need for acknowledgment of non-market, ecosystembased values connected to Treaty operations as the sovereign parties consider options for renegotiation, or modification, of the CRT. We acknowledge that many cultural and spiritual ecosystem values transcend economic values. We present this work as a comment on the fact that the contribution of ecosystems is currently valued at zero in the CRT. We organize the report in three sections, each of which aligns with one of the report’s objectives:
Section 1 outlines the past, present, and future contexts of the Treaty. We also discuss the nexus of natural resources in the Basin – food, water, energy, and biodiversity – in the context of the Treaty.
In Section 2, we detail the methods we used to arrive at our estimates of the economic benefits of ecosystem goods and services (EGS) in the CRB. We introduce the concept of natural capital valuation and describe some of the techniques researchers use to assign monetary values to nature. We also use a case study of the Arrow Lake Reservoir to discuss some of the opportunity costs BC is incurring due to the coordinated management of the river under the Treaty.
In Section 3, we explore the effects that a changing climate may have on the values of EGS and the nexus in the future. We summarize projected changes in hydrology and human development in the CRB, and identify the importance of considering these changes in a renegotiated or modified Treaty.
We conclude by making the case for including the value of ecological goods and services in any discussion of an adjusted Canadian Entitlement.
 
Intraoperative Optical Coherence Tomography-Guided Bleb-sparing Epithelial Exchange: A Modified Approach
With the advent of newer technologies, real-time anterior segment optical coherence tomography (OCT) integrated with the operating microscope has become possible. We are proposing the technique of bleb revision with greater precision under direct visualization of bleb anatomy and extent of tissue depth allowing better localization and easy maneuvering with lesser complications. In this surgical technique, bleb revision was performed using intraoperative real-time OCT incorporated in OPMI LUMERA 700 microscope. Live surgical and OCT view were seen on a common screen together. A moderately elevated, diffuse functional bleb was noted after three months of bleb revision in both cases with controlled intraocular pressure. Intraoperative OCT-guided bleb-sparing epithelial exchange is an adjunctive technique for bleb repair surgery with an increased precision of surgery which can reduce complications, minimize surgical time and maximize surgical outcome
Analyzing seasonality of tuberculosis across Indian states and union territories.
A significant seasonal variation in tuberculosis (TB) is observed in north India during 2006-2011, particularly in states like Himachal Pradesh, Haryana and Rajasthan. To quantify the seasonal variation, we measure average amplitude (peak to trough distance) across seasons in smear positive cases of TB and observe that it is maximum for Himachal Pradesh (40.01%) and minimum for Maharashtra (3.87%). In north India, smear positive cases peak in second quarter (April-June) and reach a trough in fourth quarter (October-December), however low seasonal variation is observed in southern region of the country. The significant correlations as 0.64 (p-value<0.001), 0.54 (p-value<0.01) and 0.42 (p-value<0.05) are observed between minimum temperature and seasonality of TB at lag-1 in north, central and northeast India respectively. However, in south India, this correlation is not significant
Physical trauma and risk of multiple sclerosis: A systematic review and meta-analysis of observational studies
AbstractBackgroundWe aimed to examine physical trauma as a risk factor for the subsequent diagnosis of MS.MethodsWe searched for observational studies that evaluated the risk for developing MS after physical trauma that occurred in childhood (≤20years) or “premorbid” (>20years). We performed a meta-analysis using a random effects model.ResultsWe identified 1362 individual studies, of which 36 case–control studies and 4 cohort studies met the inclusion criteria for the review. In high quality case–control studies, there were statistically significant associations between those sustaining head trauma in childhood (OR=1.27; 95% CI, 1.12–1.44; p<0.001), premorbid head trauma (OR=1.40; 95% CI, 1.08–1.81; p=0.01), and other traumas during childhood (OR=2.31; 95% CI, 1.06–5.04; p=0.04) and the risk of being diagnosed with MS. In lesser quality studies, there was a statistical association between “other traumas” premorbid and spinal injury premorbid. No association was found between spinal injury during childhood, or fractures and burns at any age and the diagnosis of MS. The pooled OR of four cohort studies looking at premorbid head trauma was not statistically significant.ConclusionsThe result of the meta-analyses of high quality case–control studies suggests a statistically significant association between premorbid head trauma and the risk for developing MS. However, cohort studies did not. Future prospective studies that define trauma based on validated instruments, and include frequency of traumas per study participant, are needed
Inhaled magnesium sulfate in the treatment of acute asthma.
BACKGROUND: Asthma exacerbations can be frequent and range in severity from mild to life-threatening. The use of magnesium sulfate (MgSO₄) is one of numerous treatment options available during acute exacerbations. While the efficacy of intravenous MgSO₄ has been demonstrated, the role of inhaled MgSO₄ is less clear. OBJECTIVES: To determine the efficacy and safety of inhaled MgSO₄ administered in acute asthma. SPECIFIC AIMS: to quantify the effects of inhaled MgSO₄ I) in addition to combination treatment with inhaled β₂-agonist and ipratropium bromide; ii) in addition to inhaled β₂-agonist; and iii) in comparison to inhaled β₂-agonist. SEARCH METHODS: We identified randomised controlled trials (RCTs) from the Cochrane Airways Group register of trials and online trials registries in September 2017. We supplemented these with searches of the reference lists of published studies and by contact with trialists. SELECTION CRITERIA: RCTs including adults or children with acute asthma were eligible for inclusion in the review. We included studies if patients were treated with nebulised MgSO₄ alone or in combination with β₂-agonist or ipratropium bromide or both, and were compared with the same co-intervention alone or inactive control. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial selection, data extraction and risk of bias. We made efforts to collect missing data from authors. We present results, with their 95% confidence intervals (CIs), as mean differences (MDs) or standardised mean differences (SMDs) for pulmonary function, clinical severity scores and vital signs; and risk ratios (RRs) for hospital admission. We used risk differences (RDs) to analyse adverse events because events were rare. MAIN RESULTS: Twenty-five trials (43 references) of varying methodological quality were eligible; they included 2907 randomised patients (2777 patients completed). Nine of the 25 included studies involved adults; four included adult and paediatric patients; eight studies enrolled paediatric patients; and in the remaining four studies the age of participants was not stated. The design, definitions, intervention and outcomes were different in all 25 studies; this heterogeneity made direct comparisons difficult. The quality of the evidence presented ranged from high to very low, with most outcomes graded as low or very low. This was largely due to concerns about the methodological quality of the included studies and imprecision in the pooled effect estimates. Inhaled magnesium sulfate in addition to inhaled β₂-agonist and ipratropiumWe included seven studies in this comparison. Although some individual studies reported improvement in lung function indices favouring the intervention group, results were inconsistent overall and the largest study reporting this outcome found no between-group difference at 60 minutes (MD -0.3 % predicted peak expiratory flow rate (PEFR), 95% CI -2.71% to 2.11%). Admissions to hospital at initial presentation may be reduced by the addition of inhaled magnesium sulfate (RR 0.95, 95% CI 0.91 to 1.00; participants = 1308; studies = 4; I² = 52%) but no difference was detected for re-admissions or escalation of care to ITU/HDU. Serious adverse events during admission were rare. There was no difference between groups for all adverse events during admission (RD 0.01, 95% CI -0.03 to 0.05; participants = 1197; studies = 2). Inhaled magnesium sulfate in addition to inhaled β₂-agonistWe included 13 studies in this comparison. Although some individual studies reported improvement in lung function indices favouring the intervention group, none of the pooled results showed a conclusive benefit as measured by FEV1 or PEFR. Pooled results for hospital admission showed a point estimate that favoured the combination of MgSO₄ and β₂-agonist, but the confidence interval includes the possibility of admissions increasing in the intervention group (RR 0.78, 95% CI 0.52 to 1.15; participants = 375; studies = 6; I² = 0%). There were no serious adverse events reported by any of the included studies and no between-group difference for all adverse events (RD -0.01, 95% CI -0.05 to 0.03; participants = 694; studies = 5). Inhaled magnesium sulfate versus inhaled β₂-agonistWe included four studies in this comparison. The evidence for the efficacy of β₂-agonists in acute asthma is well-established and therefore this could be considered a historical comparison. Two studies reported a benefit of β₂-agonist over MgSO₄ alone for PEFR and two studies reported no difference; we did not pool these results. Admissions to hospital were only reported by one small study and events were rare, leading to an uncertain result. No serious adverse events were reported in any of the studies in this comparison; one small study reported mild to moderate adverse events but the result is imprecise. AUTHORS' CONCLUSIONS: Treatment with nebulised MgSO₄ may result in modest additional benefits for lung function and hospital admission when added to inhaled β₂-agonists and ipratropium bromide, but our confidence in the evidence is low and there remains substantial uncertainty. The recent large, well-designed trials have generally not demonstrated clinically important benefits. Nebulised MgSO₄ does not appear to be associated with an increase in serious adverse events. Individual studies suggest that those with more severe attacks and attacks of shorter duration may experience a greater benefit but further research into subgroups is warranted.Despite including 24 trials in this review update we were unable to pool data for all outcomes of interest and this has limited the strength of the conclusions reached. A core outcomes set for studies in acute asthma is needed. This is particularly important in paediatric studies where measuring lung function at the time of an exacerbation may not be possible. Placebo-controlled trials in patients not responding to standard maximal treatment, including inhaled β₂-agonists and ipratropium bromide and systemic steroids, may help establish if nebulised MgSO₄ has a role in acute asthma. However, the accumulating evidence suggests that a substantial benefit may be unlikely
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