57 research outputs found
Ejidos, Land Sales, and Free Trade in Northwest Mexico: Will Globalization Affect the Commons?
Genetic variation and dispersal ecology of the lichen Erioderma pedicellatum in Newfoundland: recommendations for management of a globally rare species
Erioderma pedicellatum (Hue) P.M. Jørg is a globally rare and critically endangered lichen largely confined to the island portion of Newfoundland and Labrador. In 2002 the Boreal population was designated under the federal Species at Risk Act (SARA) as a species of "Special Concern", while the Atlantic population was listed as "Endangered". Under the provincial Endangered Species Act the lichen was designated as a "Vulnerable" species. This designation does not provide immediate protection for the lichen but requires the development of a management plan and periodic status assessment. Essential management baseline information on the species is lacking; especially on the ecology of the species as well as levels of genetic variability. This project attempts to answer key questions about the dispersal ecology of E. pedicellatum and identifies markers for analysis of genetic variation in Newfoundland and Labrador. Using the Internal Transcribed Spacer (ITS-I) of the ribosomal DNA (rDNA), two haplotypes were found among samples from Newfoundland and a single 62-year-old Swedish herbarium specimen. The common haplotype was found in both the Newfoundland samples and the Swedish sample. In addition through field research, this study describes for the first time the micro-ornamentation on the surface of E. pedicellatum spores and concludes through laboratory studies that the minute E. pedicellatum spores are actively discharged (<10 mm), can become trapped on the leg bristles or antennae of flying insects and may therefore be carried individually by these small animals. Given the high probability of an insect landing on an E. pedicellatum thallus and the shear abundance of insects in the boreal forest, our hypothesis of insects as dispersal vectors of spores is possible. We predict the potential number of insects carrying E. pedicellatum spores to be in the range of 129-161 over a 15 year period, given the calculated probability of insects landing on thalli, 4000-5000 incidences. This has important implications for forest management in E. pedicellatum habitat and further research should build on these findings by testing maximum distances spores travel in the average gap sizes of the Avalon forests, the periodicity of dispersal, and implementing harvesting /cutting block sizes to test the dispersal limitation of the species. These findings should be compared to the genetic variation of the species. This is the first study documenting the genetic variation of this rare species and the results provide significant, important information on the global population. We conclude that given the low genetic variation and the lack of variation between North American and European populations, that the global population is one evolutionary unit. This supports the IUCN designation of a globally endangered population
Early Systolic Dysfunction and Impact of Gene Mutation Severity in Marfan Syndrome
Background
Marfan syndrome is caused by a mutation in the fibrillin-1 gene that manifests with a variety of features including aortic root dilation. Recent research has identified a primary cardiomyopathy in patients with Marfan syndrome, hypothesized to be due to the presence of abnormal fibrillin-1 in the myocardium. Controversy over the nature and significance of this cardiomyopathy remains. Echocardiographic measurement of the first-phase of ejection (defined as the beginning of systole to peak aortic valve flow) may be more sensitive to systolic dysfunction and provide useful clinical information. The purpose of this study is to: Assess systolic dysfunction in patients with Marfan syndrome Describe first-phase fractional area change (FAC1) in patients with Marfan syndrome and determine how it varies between Marfan syndrome patients and a control group Verify there is a difference in propensity for cardiomyopathy in mild vs severe gene mutation Marfan syndrome patients not secondary to increased aortic stiffness
Methods
Patients were identified from a pre-existing list of patients with Marfan syndrome maintained by the Children\u27s Hospital and Medical Center and University of Nebraska Medical Center. All relevant medical records were reviewed. Echocardiographic parameters will include left ventricular (LV) ejection fraction, LV FAC1, LV end-diastolic volume, global longitudinal strain, aortic root diameter, and aortic stiffness. Patients were excluded if they have more than mild aortic insufficiency or mitral valve regurgitation. Neonatal Marfan syndrome patients and patients with other significant congenital heart disease will also be excluded. Statistical analysis of the data will be performed including basic statistical tests, univariate regression, and multivariate regression to compare data from each group. P values will be calculated and a p value \u3c 0.05 will be considered statistically significant.
Results
At the time of writing, 126 patients with Marfan syndrome have been identified. 44 were excluded based on significant mitral or aortic valve disease, prior cardiovascular surgery, or poor echocardiographic image quality. Of the 82 patients not excluded, genetic testing results are available for 59 and are being categorized to allow for statistical analysis. Echocardiographic measurements are underway.https://digitalcommons.unmc.edu/chri_forum/1002/thumbnail.jp
Impact of the COVID pandemic on vascular access creation for haemodialysis in 16 spanish haemodialysis centres
The coronavirus disease (COVID) pandemic has resulted in a major disruption in healthcare that has affected several medical and surgical specialties. European and American Vascular Societies have proposed deferring the creation of an elective vascular access (VA) [autologous or prosthetic arteriovenous fistula (AVF) or arteriovenous graft (AVG)] in incident patients on haemodialysis (HD) in the era of the COVID pandemic. The aim of this study is to examine the impact of the COVID pandemic on VA creation and the central venous catheter (CVC)-related hospitalizations and complications in HD patients dialyzed in 16 Spanish HD units of three different regions.
We compared retrospectively two periods of time: the pre-COVID (1 January 2019-11 March 2020) and the COVID era (12 March 2020-30 June 2021) in all HD patients (prevalent and incident) dialyzed in our 16 HD centres. The variables analysed were type of VA (CVC, AVF and AVG) created, percentage of CVC in incident and prevalent HD patients, CVC-related hospitalizations and complications (infection, extrusion, disfunction, catheter removal) and percentage of CVC HD sessions that did not reach the goal of Kt (>45) as a marker of HD adequacy.
A total of 1791 VAs for HD were created and 905 patients started HD during the study period. Patients who underwent vascular access surgery during the COVID period compared with pre-COVID period were significantly younger, with a significant decrease in surgical activity to create AVFs and AVGs in older HD patients (>75 and >85 years of age). There was a significant increase in CVC placement (from 59.7% to 69.5%; P 45) was observed.
COVID has presented a public health system crisis that has influenced VA for HD, with an increase in CVCs relative to AVFs. A decrease in HD sessions that did not reach the HD dose objective was observed in the COVID period compared with a pre-COVID period
Interventions for preventing ophthalmia neonatorum.
BACKGROUND: Ophthalmia neonatorum is an infection of the eyes in newborns that can lead to blindness, particularly if the infection is caused by Neisseria gonorrhoeae. Antiseptic or antibiotic medication is dispensed into the eyes of newborns, or dispensed systemically, soon after delivery to prevent neonatal conjunctivitis and potential vision impairment. OBJECTIVES: 1. To determine if any type of systemic or topical eye medication is better than placebo or no prophylaxis in preventing ophthalmia neonatorum. 2. To determine if any one systemic or topical eye medication is better than any other medication in preventing ophthalmia neonatorum. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS, and three trials registers, date of last search 4 October 2019. We also searched references of included studies and contacted pharmaceutical companies. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials of any topical, systemic, or combination medical interventions used to prevent ophthalmia neonatorum in newborns compared with placebo, no prophylaxis, or with each other. DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. Outcomes were: blindness or any adverse visual outcome at 12 months, conjunctivitis at 1 month (gonococcal (GC), chlamydial (CC), bacterial (BC), any aetiology (ACAE), or unknown aetiology (CUE)), and adverse effects. MAIN RESULTS: We included 30 trials with a total of 79,198 neonates. Eighteen studies were conducted in high-income settings (the USA, Europe, Israel, Canada), and 12 were conducted in low- and middle-income settings (Africa, Iran, China, Indonesia, Mexico). Fifteen of the 30 studies were quasi-randomised. We judged every study to be at high risk of bias in at least one domain. Ten studies included a comparison arm with no prophylaxis. There were 14 different prophylactic regimens and 12 different medications in the 30 included studies. Any prophylaxis compared to no prophylaxis Unless otherwise indicated, the following evidence comes from studies assessing one or more of the following interventions: tetracycline 1%, erythromycin 0.5%, povidone-iodine 2.5%, silver nitrate 1%. None of the studies reported data on the primary outcomes: blindness or any adverse visual outcome at any time point. There was only very low-certainty evidence on the risk of GC with prophylaxis (4/5340 newborns) compared to no prophylaxis (5/2889) at one month (risk ratio (RR) 0.79, 95% confidence interval (CI) 0.24 to 2.65, 3 studies). Low-certainty evidence suggested there may be little or no difference in effect on CC (RR 0.96, 95% CI 0.57 to 1.61, 4874 newborns, 2 studies) and BC (RR 0.84, 95% CI 0.37 to 1.93, 3685 newborns, 2 studies). Moderate-certainty evidence suggested a probable reduction in risk of ACAE at one month (RR 0.65, 95% 0.54 to 0.78, 9666 newborns, 8 studies assessing tetracycline 1%, erythromycin 0.5%, povidone-iodine 2.5%, silver nitrate 1%, colostrum, bacitracin-phenacaine ointment). There was only very low-certainty evidence on CUE (RR 1.75, 95% CI 0.37 to 8.28, 330 newborns, 1 study). Very low-certainty evidence on adverse effects suggested no increased nasolacrimal duct obstruction (RR 0.93, 95% CI 0.68 to 1.28, 404 newborns, 1 study of erythromycin 0.5% and silver nitrate 1%) and no increased keratitis (single study of 40 newborns assessing silver nitrate 1% with no events). Any prophylaxis compared to another prophylaxis Overall, evidence comparing different interventions did not suggest any consistently superior intervention. However, most of this evidence was of low-certainty and was extremely limited. AUTHORS' CONCLUSIONS: There are no data on whether prophylaxis for ophthalmia neonatorum prevents serious outcomes such as blindness or any adverse visual outcome. Moderate-certainty evidence suggests that the use of prophylaxis may lead to a reduction in the incidence of ACAE in newborns but the evidence for effect on GC, CC or BC was less certain. Comparison of individual interventions did not suggest any consistently superior intervention, but data were limited. A trial comparing tetracycline, povidone-iodine (single administration), and chloramphenicol for GC and CC could potentially provide the community with an effective, universally applicable prophylaxis against ophthalmia neonatorum
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