2,992 research outputs found
Validation of the Patient Perception of Intensity of Urgency Scale in Patients with Lower Urinary Tract Symptoms Associated with Benign Prostatic Hyperplasia
AbstractObjectiveTo assess the reliability and validity of scores derived from the Patient Perception of Intensity of Urgency Scale (PPIUS) in patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).MethodsA post hoc analysis of the phase II Solifenacin and Tamsulosin in Males with Lower Urinary Tract Symptoms Associated with Benign Prostatic Hyperplasia trial (NCT00510406), a 12-week clinical trial in men with LUTS associated with BPH, assessed the measurement properties of six PPIUS-derived scores: mean score; maximum urgency score; total urgency and frequency score (TUFS; average sum of urgency scores over 3 days); and numbers of urgency episodes, urgency episodes of grade 3 or 4, and urgency incontinence episodes. Test-retest reliability, presence of floor/ceiling effects, responsiveness to change, known-group validity, and concurrent validity were assessed for each score.ResultsA total of 901 patients had at least one valid PPIUS assessment after baseline. TUFS demonstrated good test-retest reliability (intraclass correlation coefficient >0.8), discriminated between groups defined based on International Prostate Symptom Score storage score severity (known-groups validity), had high concurrent validity, and had high responsiveness to change (Guyattâs responsiveness statistic 0.88), with an absence of floor or ceiling effects. The psychometric properties of other PPIUS-derived scores were not as consistently robust and showed either low-to-moderate responsiveness, presence of a floor or ceiling effect, or low-to-moderate test-retest reliability.ConclusionsThis study shows that the PPIUS is reliable and valid in patients with LUTS associated with BPH. TUFS provided the best combination of psychometric properties of the six scores derived from the PPIUS and appeared to be an appropriate measure of urgency and frequency
Evaluating Genetic Viability of Pronghorn in Wind Cave National Park
The pronghorn (Antilocapra americana) was reintroduced into Wind Cave National Park, South Dakota, in 1914 and thus, has inhabited the Park for almost a century. A decline in the population has raised concern for the continued existence of pronghorn inside Wind Cave National Park. Historically, pronghorn numbers reached greater than 300 individuals in the 1960\u27s but declined to about 30 individuals by 2002. The primary objective of our study was to evaluate genetic characteristics of pronghorn to determine if reduced heterozygosity contributed to the decline of pronghorn in Wind Cave National Park. Microsatellite DNA was collected from 75 pronghorn inhabiting Wind Cave National Park in western South Dakota (n = 11), northwestern South Dakota (n = 33), and southwestern South Dakota (n = 31). Pronghorn in Wind Cave National Park had similar levels of observed heterozygosity (0.473 to 0.594) and low inbreeding coefficients (-0.168 to 0.037) when compared with other populations in western South Dakota. Furthermore, indices of population structure indicated no differentiation occurred among pronghorn populations. Results indicated that genetic variability was not a primary factor in the decline of pronghorn in Wind Cave National Park
A Method of Drusen Measurement Based on the Geometry of Fundus Reflectance
BACKGROUND: The hallmarks of age-related macular degeneration, the leading cause of blindness in the developed world, are the subretinal deposits known as drusen. Drusen identification and measurement play a key role in clinical studies of this disease. Current manual methods of drusen measurement are laborious and subjective. Our purpose was to expedite clinical research with an accurate, reliable digital method. METHODS: An interactive semi-automated procedure was developed to level the macular background reflectance for the purpose of morphometric analysis of drusen. 12 color fundus photographs of patients with age-related macular degeneration and drusen were analyzed. After digitizing the photographs, the underlying background pattern in the green channel was leveled by an algorithm based on the elliptically concentric geometry of the reflectance in the normal macula: the gray scale values of all structures within defined elliptical boundaries were raised sequentially until a uniform background was obtained. Segmentation of drusen and area measurements in the central and middle subfields (1000 ÎŒm and 3000 ÎŒm diameters) were performed by uniform thresholds. Two observers using this interactive semi-automated software measured each image digitally. The mean digital measurements were compared to independent stereo fundus gradings by two expert graders (stereo Grader 1 estimated the drusen percentage in each of the 24 regions as falling into one of four standard broad ranges; stereo Grader 2 estimated drusen percentages in 1% to 5% intervals). RESULTS: The mean digital area measurements had a median standard deviation of 1.9%. The mean digital area measurements agreed with stereo Grader 1 in 22/24 cases. The 95% limits of agreement between the mean digital area measurements and the more precise stereo gradings of Grader 2 were -6.4 % to +6.8 % in the central subfield and -6.0 % to +4.5 % in the middle subfield. The mean absolute differences between the digital and stereo gradings 2 were 2.8 +/- 3.4% in the central subfield and 2.2 +/- 2.7% in the middle subfield. CONCLUSIONS: Semi-automated, supervised drusen measurements may be done reproducibly and accurately with adaptations of commercial software. This technique for macular image analysis has potential for use in clinical research
Book Review of Serendipity: An Ecologistâs Quest to Understand Nature
A common thought among graduate students is: âhow do established scientists get where they are today?â In Serendipity: An Ecologistâs Quest to Understand Nature, James Estes offers a personal reflection on research experiences spanning his 50-year career, beginning as a Ph.D. student in 1970 and concluding with recognition as a member of the National Academy of Sciences in 2014. Estes chronologically outlines the foundational trophic cascade ecology research that he and colleagues conducted in the Aleutian Islands, examining key relationships among kelp forests, sea otters, sea urchins, and killer whales through anecdotal stories of achievement and challenge. Estesâ 3 main goals in writing this book are to: (1) recount what he had learned from 50 years of research; (2) provide a larger story of how predators and prey interact with one another; and (3) explain how science âreally happens.
Dietary nitrate intake is associated with decreased incidence of open-angle Glaucoma: The Rotterdam study
Previous studies suggest that nitric oxide is involved in the regulation of the intraocular pressure (IOP) and in the pathophysiology of open-angle glaucoma (OAG). However, prospective studies investigating the association between dietary nitrate intake, a source of nitric oxide, and incident (i)OAG risk are limited. We aimed to determine the association between dietary nitrate intake and iOAG, and to evaluate the association between dietary nitrate intake and IOP. From 1991 onwards, participants were followed each five years for iOAG in the Rotterdam Study. A total of 173 participants developed iOAG during follow-up. Cases and controls were matched on age (mean ± standard deviation: 65.7 ± 6.9) and sex (%female: 53.2) in a case:control ratio of 1:5. After adjustment for potential confounders, total dietary nitrate intake was associated with a lower iOAG risk (odds ratio (OR) with corresponding 95% confidence interval (95% CI): 0.95 (0.91â0.98) for each 10 mg/day higher intake). Both nitrate intake from vegetables (OR (95% CI): 0.95 (0.91â0.98) for each 10 mg/day higher intake) and nitrate intake from non-vegetable food sources (OR (95% CI): 0.63 (0.41â0.96) for each 10 mg/day higher intake) were associated with a lower iOAG risk. Dietary nitrate intake was not associated with IOP. In conclusion, dietary nitrate intake was associated with a reduced risk of iOAG. IOP-independent mechanisms may underlie the association with OAG
Review of Large Carnivore Conservation: Integrating Science and Policy in the North American West
The management and conservation of large carnivores is of worldwide concern and is as much about human values, interactions, and governance as carnivore biology. Susan Clark and Murray Rutherford continue their work on coexisting with large carnivores ( Clark et al. 2005 ) with a new edited volume Large Carnivore Conservation: Integrating Science and Policy in the North American West . Large Carnivore Conservation that expands on the same themes as their previous work with case studies from Arizona to the Yukon. While focusing on the North American West, Clark and Rutherford hope to provide a holistic approach to carnivore management in general
Evidence that emmetropization buffers against both genetic and environmental risk factors for myopia
YesPURPOSE. To test the hypothesis that emmetropization buffers against genetic and environmental
risk factors for myopia by investigating whether risk factor effect sizes vary
depending on childrenâs position in the refractive error distribution.
METHODS. Refractive error was assessed in participants from two birth cohorts: Avon
Longitudinal Study of Parents and Children (ALSPAC) (noncycloplegic autorefraction) and
Generation R (cycloplegic autorefraction). A genetic risk score for myopia was calculated
from genotypes at 146 loci. Time spent reading, time outdoors, and parental myopia were
ascertained from parent-completed questionnaires. Risk factors were coded as binary
variables (0 = low, 1 = high risk). Associations between refractive error and each risk
factor were estimated using either ordinary least squares (OLS) regression or quantile
regression.
RESULTS. Quantile regression: effects associated with all risk factors (genetic risk,
parental myopia, high time spent reading, low time outdoors) were larger for children
in the extremes of the refractive error distribution than for emmetropes and low
ametropes in the center of the distribution. For example, the effect associated with
having a myopic parent for children in quantile 0.05 vs. 0.50 was as follows: ALSPAC:
age 15, â1.19 D (95% CI â1.75 to â0.63) vs. â0.13 D (â0.19 to â0.06), P = 0.001; Generation
R: age 9, â1.31 D (â1.80 to â0.82) vs. â0.19 D (â0.26 to â0.11), P < 0.001. Effect sizes
for OLS regression were intermediate to those for quantiles 0.05 and 0.50.
CONCLUSIONS. Risk factors for myopia were associated with much larger effects in children
in the extremes of the refractive error distribution, providing indirect evidence that
emmetropization buffers against both genetic and environmental risk factors.UK Medical Research Council and Wellcome (grant ref: 102215/2/13/2), and the University of Bristol provided core support for ALSPAC. This research was specifically funded by the UK National Eye Research Centre (grant SAC015), the Global Education Program of the Russian Federation government, a PhD studentship grant from the UK College of Optometrists (âGenetic Prediction of Individuals At-Risk for Myopia Developmentâ), and an NIHR Senior Research Fellowship award SRF-2015-08-005. The Generation R study is supported by the Erasmus Medical Center, Rotterdam, Erasmus University, Rotterdam, the Netherlands; the Netherlands Organization of Scientific Research (NWO); Netherlands Organization for the Health Research and Development (ZonMw); the Ministry of Education, Culture and Science; the Ministry for Health,Welfare and Sports; the European Commission (DG XII); European Research Council (ERC) under the European Unionâs Horizon 2020 Research and Innovation Programme (grant 648268); the Netherlands Organization for Scientific Research (NWO, grant 91815655); and Oogfonds, ODAS, Uitzicht 2017-28 (LSBS, MaculaFonds, Oogfonds)
The inflammatory potential of diet is associated with the risk of age-related eye diseases
Background & aims: Inflammation is involved in the pathogenesis of cataract, age-related macular degeneration (AMD), and possibly open-angle glaucoma (OAG). We assessed whether the inflammatory potential of diet (quantified using the dietary inflammatory index; DII) affects the incidence of these common blinding age-related eye diseases. Serum inflammation markers were investigated as possible mediators.Methods: Participants aged >45 years were selected from the prospective, population-based Rotterdam Study. From 1991 onwards, every 4â5 years, participants underwent extensive eye examinations. At baseline, blood samples and dietary data (using food frequency questionnaires) were collected. The DII was adapted based on the data available. Of the 7436 participants free of eye diseases at baseline, 4036 developed incident eye diseases during follow-up (cataract = 2895, early-intermediate AMD = 891, late AMD = 81, OAG = 169). Results: The adapted DII (aDII) ranged from â4.26 (i.e., anti-inflammatory) to 4.53 (i.e., pro-inflammatory). A higher aDII was significantly associated with increased inflammation. A higher neutrophil-lymphocyte ratio (NLR) was associated with an increased risk of cataract and AMD. Additionally, complement component 3c (C3c) and systemic immune-inflammation index (SII) were associated with increased risks of cataract and late AMD, respectively. Every point increase in the aDII was associated with a 9% increased risk of cataract (Odds ratio [95% confidence interval]: 1.09 [1.04â1.14]). The NLR and C3c partly mediated this association. We also identified associations of the aDII with risk of AMD (early-intermediate AMD, OR [95% CI]: 1.11 [1.03â1.19]; late AMD, OR [95% CI]: 1.24 [1.02â1.53]). The NLR partly mediated these associations. The aDII was not associated with OAG. Conclusions: A pro-inflammatory diet was associated with increased risks of cataract and AMD. Particularly the NLR, a marker of subclinical inflammation, appears to be implicated. These findings are relevant for patients with AMD and substantiate the current recommendations to strive for a healthy lifestyle to prevent blindness.</p
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