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1.
Ophthalmology ; 130(1): 14-27, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35973593

RESUMEN

PURPOSE: To determine clinical effectiveness, safety, and cost-effectiveness of subthreshold micropulse laser (SML), compared with standard laser (SL), for diabetic macular edema (DME) with central retinal thickness (CRT) < 400 µm. DESIGN: Pragmatic, multicenter, allocation-concealed, double-masked, randomized, noninferiority trial. PARTICIPANTS: Adults with center-involved DME < 400 µm and best-corrected visual acuity (BCVA) of > 24 Early Treatment Diabetic Retinopathy Study (ETDRS) letters in one/both eyes. METHODS: Randomization 1:1 to 577 nm SML or SL treatment. Retreatments were allowed. Rescue with intravitreal anti-vascular endothelial growth factor therapies or steroids was permitted if 10 or more ETDRS letter loss occurred, CRT increased > 400 µm, or both. MAIN OUTCOME MEASURES: Primary outcome was mean change in BCVA in the study eye at 24 months (noninferiority margin 5 ETDRS letters). Secondary outcomes were mean change from baseline to month 24 in binocular BCVA; CRT and mean deviation of Humphrey 10-2 visual field in the study eye; percentage meeting driving standards; EuroQoL EQ-5D-5L, 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25), and Vision and Quality of Life Index (VisQoL) scores; cost per quality-adjusted life-years (QALYs) gained; adverse effects; and number of laser and rescue treatments. RESULTS: The study recruited fully (n = 266); 87% of SML-treated and 86% of SL-treated patients had primary outcome data. Mean ± standard deviation BCVA change from baseline to month 24 was -2.43 ± 8.20 letters and -0.45 ± 6.72 letters in the SML and SL groups, respectively. Subthreshold micropulse laser therapy was deemed not only noninferior but also equivalent to SL therapy because the 95% confidence interval (CI; -3.9 to -0.04 letters) lay wholly within both upper and lower margins of the permitted maximum difference (5 ETDRS letters). No statistically significant difference was found in binocular BCVA (0.32 ETDRS letters; 95% CI, -0.99 to 1.64 ETDRS letters; P = 0.63); CRT (-0.64 µm; 95% CI, -14.25 to 12.98 µm; P = 0.93); mean deviation of the visual field (0.39 decibels (dB); 95% CI, -0.23 to 1.02 dB; P = 0.21); meeting driving standards (percentage point difference, 1.6%; 95% CI, -25.3% to 28.5%; P = 0.91); adverse effects (risk ratio, 0.28; 95% CI, 0.06-1.34; P = 0.11); rescue treatments (percentage point difference, -2.8%; 95% CI, -13.1% to 7.5%; P = 0.59); or EQ-5D, NEI-VFQ-25, or VisQoL scores. Number of laser treatments was higher in the SML group (0.48; 95% CI, 0.18-0.79; P = 0.002). Base-case analysis indicated no differences in costs or QALYs. CONCLUSIONS: Subthreshold micropulse laser therapy was equivalent to SL therapy, requiring slightly higher laser treatments.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Adulto , Humanos , Edema Macular/tratamiento farmacológico , Retinopatía Diabética/cirugía , Retinopatía Diabética/tratamiento farmacológico , Calidad de Vida , Coagulación con Láser/efectos adversos , Agudeza Visual , Retina , Inyecciones Intravítreas , Inhibidores de la Angiogénesis , Ranibizumab/uso terapéutico
2.
Am J Primatol ; 85(11): e23544, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37572084

RESUMEN

Monitoring populations is critical for understanding how they respond to anthropogenic disturbance and for management of protected areas. The use of passive acoustic monitoring can improve monitoring efforts as it allows for collection of data on vocal animals at spatial and temporal scales that are difficult using only human observers. In this study, we used a multiseason occupancy model to monitor occurrence, apparent extinction, and colonization probabilities of a northern yellow-cheeked gibbon, Nomascus annamensis population with acoustic data collected from mobile smartphones in Dakrong Nature Reserve, Vietnam. Forty-five sites were randomly selected for repeated surveys in 2019 and 2022. At each site, a mobile smartphone was attached to a tree and recorded sounds for 4.2 days and 3.89 days on average, in 2019 and 2022, respectively. We manually annotated spectrograms for the presence of gibbon calls, and we detected gibbons at 24 and 12 recording posts in 2019 and 2022, respectively. Estimated local apparent extinction from occupancy models was high with 67% of occupied sites in 2019 becoming unoccupied in 2022. Apparent colonization was low with ~25% of unoccupied sites in 2019 becoming occupied in 2022. As a result, the apparent occurrence probability declined from 0.58 in 2019 to 0.30 in 2022. If the absence of calls indicates that cells are unoccupied this would mean an alarming decline of the gibbon population in the nature reserve. We suggest that in the areas with high hunting pressure, monitoring intervals should be shortened to at least yearly. In addition, urgent actions, such as patrolling, or gun confiscation, should be implemented to conserve the gibbon populations in Dakrong Nature Reserve and other protected areas with the same management context.

3.
Ecol Appl ; 31(2): e2245, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33098602

RESUMEN

Emerging diseases of wildlife origin are increasingly spilling over into humans and domestic animals. Surveillance and risk assessments for transmission between these populations are informed by a mechanistic understanding of the pathogens in wildlife reservoirs. For avian influenza viruses (AIV), much observational and experimental work in wildlife has been conducted at local scales, yet fully understanding their spread and distribution requires assessing the mechanisms acting at both local, (e.g., intrinsic epidemic dynamics), and continental scales, (e.g., long-distance migration). Here, we combined a large, continental-scale data set on low pathogenic, Type A AIV in the United States with a novel network-based application of bird banding/recovery data to investigate the migration-based drivers of AIV and their relative importance compared to well-characterized local drivers (e.g., demography, environmental persistence). We compared among regression models reflecting hypothesized ecological processes and evaluated their ability to predict AIV in space and time using within and out-of-sample validation. We found that predictors of AIV were associated with multiple mechanisms at local and continental scales. Hypotheses characterizing local epidemic dynamics were strongly supported, with age, the age-specific aggregation of migratory birds in an area and temperature being the best predictors of infection. Hypotheses defining larger, network-based features of the migration processes, such as clustering or between-cluster mixing explained less variation but were also supported. Therefore, our results support a role for local processes in driving the continental distribution of AIV.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , Aves , Demografía , Humanos , Gripe Aviar/epidemiología , Temperatura , Estados Unidos
4.
Prev Sci ; 20(6): 844-851, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30637672

RESUMEN

The aim of this study was to examine the extent of recanting (inconsistencies in reporting of lifetime alcohol use) and its impact on the assessment of primary outcomes within a large-scale alcohol prevention trial. One hundred and five post-primary schools in were randomised to receive either the intervention or education as normal. Participants (N = 12,738) were secondary school students in year 8/S1 (mean age 12.5) at baseline. Self-report questionnaires were administered at baseline (T0) and at T1 (+ 12 months post-baseline), T2 (+ 24 months) and T3 (+ 33 months). The primary outcomes were (i) heavy episodic drinking (consumption of ≥ 6 units in a single episode in the previous 30 days for males and ≥ 4.5 units for females) assessed at T3 and (ii) the number of alcohol-related harms experienced in the last 6 months assessed at T3. Recanting was defined as a negative report of lifetime alcohol consumption that contradicted a prior positive report. Between T1 and T3, 9.9% of students recanted earlier alcohol consumption. Recanting ranged from 4.5 to 5.3% across individual data sweeps. While recanting was significantly associated (negatively) with both primary outcomes, the difference in the rate of recanting across trial arms was small, and adjusting for recanting within the primary outcome models did not impact on the primary outcome effects. Males were observed to recant at a greater rate than females, with a borderline small-sized effect (V = .09). While differential rates of recanting have the potential to undermine the analysis of prevention trial outcomes, recanting is easy to identify and control for within trial primary outcome analyses. Adjusting for recanting should be considered as an additional sensitivity test within prevention trials.Trial Registration: ISRCTN47028486 ( http://www.isrctn.com/ISRCTN47028486 ). The date of trial registration was 23/09/2011, and school recruitment began 01/11/2011.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Estudiantes , Adolescente , Niño , Análisis por Conglomerados , Femenino , Humanos , Masculino , Autoinforme , Reino Unido/epidemiología
5.
Am J Primatol ; 80(9): e22903, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30152533

RESUMEN

All 18 species of gibbons are considered threatened with extinction and listed on the IUCN Red List of Threatened Species. Because gibbons (Hylobatidae) are one of the most threatened primate families, a great need exists to determine and monitor their status effectively. To meet this need, we employed distance sampling methods to estimate the density and number of gibbon groups. We focused on southern yellow-cheeked crested gibbon in the Nam Cat Tien sector of Cat Tien National Park, Vietnam, from July to October, 2016. We used an auditory point count method at 48 listening posts to detect gibbon groups. We estimated our detection probability of calling groups of gibbons within 1,200 m of a listening post was 0.63 (95% CI: 0.54-0.74). In addition, we estimated the daily calling probability of a gibbon group to be 0.46 (95% CI: 0.33-0.59) and interpreted this as the probability that a group was available to be detected. We adjusted our group density and abundance estimates by both detection and availability probabilities. Ultimately we estimated 325 (95% CI: 232-455) gibbon groups in the Nam Cat Tien sector. Our results suggest that Cat Tien National Park contains one of the largest populations of southern yellow-cheeked crested gibbon in Vietnam. Our methods are one way of avoiding underestimation of gibbon group density and abundance by incorporating uncertainty in gibbon group availability and detection.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Hylobatidae/fisiología , Animales , Ecología/métodos , Especies en Peligro de Extinción , Densidad de Población , Vietnam
6.
J Urol ; 188(4 Suppl): 1588-95, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22910261

RESUMEN

PURPOSE: In girls with congenital adrenal hyperplasia the degree to which excess androgen exposure leads to the development of prostatic tissue is largely uncharacterized, except in rare case reports of prostatic growth and adenocarcinoma. Such growth yields concern for future malignant degeneration. MATERIALS AND METHODS: Chart review identified 43 adult women with congenital adrenal hyperplasia who had been longitudinally followed from birth, of whom 11 were available for history and physical examination, laboratory testing for androgen metabolites, and pelvic magnetic resonance imaging. RESULTS: Periurethral thickening was noted on digital rectal examination in 1 patient with increased 17-hydroxyprogesterone and tissue analogous to prostatic tissue was impalpable in the remaining 10. Prostate specific antigen was 0.2 ng/ml in another patient with notably increased testosterone, androstenedione, dihydrotestosterone and 17-hydroxyprogesterone, and was less than 0.1 ng/ml in the remaining patients. Magnetic resonance imaging revealed an absence of definitive prostatic tissue in all 11 patients despite evidence of genitourinary masculinization in all. Of the 11 women 7 had marked androgen excess. CONCLUSIONS: Despite androgen excess and genitourinary masculinization in patients with congenital adrenal hyperplasia, as well as case reports citing evidence of prostatic tissue and adenocarcinoma in these women, our study successfully documents the absence of notable prostatic growth in these patients. A better understanding of the timing and factors involved in prostatic growth would aid in identifying the degree to which adult women with congenital adrenal hyperplasia are at risk for adverse sequelae of Skene gland growth.


Asunto(s)
Hiperplasia Suprarrenal Congénita/patología , Próstata/crecimiento & desarrollo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Health Technol Assess ; 26(50): 1-86, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36541393

RESUMEN

BACKGROUND: The National Institute for Health and Care Excellence recommends macular laser to treat diabetic macular oedema with a central retinal subfield thickness of < 400 µm on optical coherence tomography. The DIAMONDS (DIAbetic Macular Oedema aNd Diode Subthreshold micropulse laser) trial compared standard threshold macular laser with subthreshold micropulse laser to treat diabetic macular oedema suitable for macular laser. OBJECTIVES: Determining the clinical effectiveness, safety and cost-effectiveness of subthreshold micropulse laser compared with standard threshold macular laser to treat diabetic macular oedema with a central retinal subfield thickness of < 400 µm. DESIGN: A pragmatic, multicentre, allocation-concealed, double-masked, randomised, non-inferiority, clinical trial. SETTING: Hospital eye services in the UK. PARTICIPANTS: Adults with diabetes and centre-involving diabetic macular oedema with a central retinal subfield thickness of < 400 µm, and a visual acuity of > 24 Early Treatment Diabetic Retinopathy Study letters (Snellen equivalent > 20/320) in one/both eyes. INTERVENTIONS: Participants were randomised 1 : 1 to receive 577 nm subthreshold micropulse laser or standard threshold macular laser (e.g. argon laser, frequency-doubled neodymium-doped yttrium aluminium garnet 532 nm laser); laser treatments could be repeated as needed. Rescue therapy with intravitreal anti-vascular endothelial growth factor therapies or steroids was allowed if a loss of ≥ 10 Early Treatment Diabetic Retinopathy Study letters between visits occurred and/or central retinal subfield thickness increased to > 400 µm. MAIN OUTCOME MEASURES: The primary outcome was the mean change in best-corrected visual acuity in the study eye at 24 months (non-inferiority margin 5 Early Treatment Diabetic Retinopathy Study letters). Secondary outcomes included the mean change from baseline to 24 months in the following: binocular best-corrected visual acuity; central retinal subfield thickness; the mean deviation of the Humphrey 10-2 visual field in the study eye; the percentage of people meeting driving standards; and the EuroQol-5 Dimensions, five-level version, National Eye Institute Visual Function Questionnaire - 25 and Vision and Quality of Life Index scores. Other secondary outcomes were the cost per quality-adjusted life-years gained, adverse effects, number of laser treatments and additional rescue treatments. RESULTS: The DIAMONDS trial recruited fully (n = 266); 87% of participants in the subthreshold micropulse laser group and 86% of participants in the standard threshold macular laser group had primary outcome data. Groups were balanced regarding baseline characteristics. Mean best-corrected visual acuity change in the study eye from baseline to month 24 was -2.43 letters (standard deviation 8.20 letters) in the subthreshold micropulse laser group and -0.45 letters (standard deviation 6.72 letters) in the standard threshold macular laser group. Subthreshold micropulse laser was deemed to be not only non-inferior but also equivalent to standard threshold macular laser as the 95% confidence interval (-3.9 to -0.04 letters) lay wholly within both the upper and lower margins of the permitted maximum difference (5 Early Treatment Diabetic Retinopathy Study letters). There was no statistically significant difference between groups in any of the secondary outcomes investigated with the exception of the number of laser treatments performed, which was slightly higher in the subthreshold micropulse laser group (mean difference 0.48, 95% confidence interval 0.18 to 0.79; p = 0.002). Base-case analysis indicated no significant difference in the cost per quality-adjusted life-years between groups. FUTURE WORK: A trial in people with ≥ 400 µm diabetic macular oedema comparing anti-vascular endothelial growth factor therapy alone with anti-vascular endothelial growth factor therapy and macular laser applied at the time when central retinal subfield thickness has decreased to < 400 µm following anti-vascular endothelial growth factor injections would be of value because it could reduce the number of injections and, subsequently, costs and risks and inconvenience to patients. LIMITATIONS: The majority of participants enrolled had poorly controlled diabetes. CONCLUSIONS: Subthreshold micropulse laser was equivalent to standard threshold macular laser but required a slightly higher number of laser treatments. TRIAL REGISTRATION: This trial is registered as EudraCT 2015-001940-12, ISRCTN17742985 and NCT03690050. FUNDING: This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 50. See the NIHR Journals Library website for further project information.


The retina is a layer at the back of the eye. Its centre is called the macula and is responsible for central vision. Some people with diabetes develop diabetic macular oedema. In diabetic macular oedema fluid leaks from retinal blood vessels and builds up at the macula, resulting in sight loss. Diabetic macular oedema can be mild or severe; this can be determined measuring the thickness of the macula, which is measured in micrometres (µm). One micrometre is one thousandth of a millimetre. In mild diabetic macular oedema, the thickness of the macula increases, but is less than 400 µm. Patients with mild diabetic macular oedema can be treated with a laser and there are two laser types. The standard threshold macular laser has been available for many years. It clears the diabetic macular oedema but produces a 'burn' in the retina. The subthreshold micropulse laser is newer. It does not produce a burn but also clears the diabetic macular oedema. The lack of a burn, however, has led to doubts about whether or not this laser works as well as the standard threshold macular laser because 'no burn' was taken to mean 'less benefit'. These doubts led to our establishing the DIAMONDS (DIAbetic Macular Oedema aNd Diode Subthreshold micropulse laser) trial, which compared these two lasers for people with mild diabetic macular oedema. A total of 266 people suitable for either laser joined the study at 16 NHS hospitals across the UK; 133 received standard threshold macular laser and 133 received subthreshold micropulse laser. The choice of laser was determined by chance. The DIAMONDS trial found that the subthreshold micropulse laser was as good as the standard threshold macular laser (i.e. 'clinically equivalent') in terms of improving people's vision, reducing macula thickness, allowing people to meet driving standards and maintaining their quality of life, both in general terms and for vision in particular. There was a small increase (less than one session on average per person) in the number of laser treatment sessions needed with subthreshold micropulse laser. The costs of both laser treatments were about the same.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Adulto , Edema Macular/cirugía , Retinopatía Diabética/cirugía , Ranibizumab/efectos adversos , Bevacizumab/efectos adversos , Calidad de Vida , Factores de Crecimiento Endotelial/uso terapéutico , Coagulación con Láser/efectos adversos , Coagulación con Láser/métodos , Rayos Láser
8.
Biol Lett ; 7(2): 303-6, 2011 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20943677

RESUMEN

Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (Sula sula), using a 19 year mark-recapture dataset involving more than 11,000 birds. We showed that skipping breeding was more likely in El-Niño years, correlated with an increase in the local sea surface temperature, supporting the hypothesis that it may be partly an adaptive strategy of birds to face the trade-off between survival and reproduction owing to environmental constraints. We also showed that the age-specific probability of first breeding attempt was synchronized among different age-classes and higher in El-Niño years. This result suggested that pre-breeders may benefit from lowered competition with experienced breeders in years of high skipping probabilities.


Asunto(s)
Aves/fisiología , Cruzamiento , El Niño Oscilación del Sur , Conducta Sexual Animal , Adaptación Fisiológica , Animales , Modelos Biológicos , Estaciones del Año , Agua de Mar/química , Temperatura
9.
Parasit Vectors ; 14(1): 145, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33685479

RESUMEN

BACKGROUND: The prevalence of avian haemosporidian parasites and the factors influencing infection in the Colorado Rocky Mountains are largely unknown. With climate change expected to promote the expansion of vector and avian blood parasite distributions, baseline knowledge and continued monitoring of the prevalence and diversity of these parasites is needed. METHODS: Using an occupancy modeling framework, we conducted a survey of haemosporidian parasite species infecting an avian community in the Colorado Rocky Mountains in order to estimate the prevalence and diversity of blood parasites and to investigate species-level and individual-level characteristics that may influence infection. RESULTS: We estimated the prevalence and diversity of avian Haemosporidia across 24 bird species, detecting 39 parasite haplotypes. We found that open-cup nesters have higher Haemoproteus prevalence than cavity or ground nesters. Additionally, we found that male Ruby-crowned Kinglets, White-crowned Sparrows, and Wilson's Warblers have higher Haemoproteus prevalence compared to other host species. Plasmodium prevalence was relatively low (5%), consistent with the idea that competent vectors may be rare at high altitudes. CONCLUSIONS: Our study presents baseline knowledge of haemosporidian parasite presence, prevalence, and diversity among avian species in the Colorado Rocky Mountains and adds to our knowledge of host-parasite relationships of blood parasites and their avian hosts.


Asunto(s)
Enfermedades de las Aves/parasitología , Aves/parasitología , Haemosporida/genética , Interacciones Huésped-Parásitos , Comportamiento de Nidificación , Infecciones Protozoarias en Animales/epidemiología , Animales , Enfermedades de las Aves/epidemiología , Colorado/epidemiología , Femenino , Variación Genética , Haemosporida/clasificación , Haemosporida/patogenicidad , Especificidad del Huésped , Masculino , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/sangre , Factores Sexuales
10.
Ecology ; 91(11): 3365-75, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21141197

RESUMEN

Researchers often rely on capture-mark-recapture (CMR) data to study animal dispersal in the wild. Yet their spatial coverage often does not encompass the entire dispersal range of the study individuals, sometimes producing misleading results. Information contained in population surveys and variation in population spatial structure can be used to overcome this issue. We build an integrated model in a multisite context in which CMR data are only collected at a subset of sites, but numbers of breeding pairs are counted at all sites. In a Black-headed Gull Chroicocephalus ridibundus population, the integrated-modeling approach induces an increase in precision for the demographic parameters of interest (variances, on average, were decreased by 20%) and provides a more precise extrapolation of results from the CMR data to the whole population. Patterns of condition-dependent dispersal are therefore made easier to detect, and we obtain evidence for colony-size dependence in recruitment, dispersal, and breeding success. These results suggest that first-time breeders disperse to small colonies in order to recruit earlier. The exchange of experienced breeders between colonies appears as a main determinant of the observed variation in colony sizes.


Asunto(s)
Charadriiformes/fisiología , Ecosistema , Animales , Demografía , Modelos Biológicos , Conducta Sexual Animal , Factores de Tiempo
11.
J Med Entomol ; 47(5): 897-901, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20939387

RESUMEN

The cliff swallow (Petrochelidon pyrrhonota, Vieillot) could potentially play an important role in the transmission of West Nile virus (WNV) because of its breeding ecology, reservoir competence status, and potentially high natural exposure rates. These birds nest in colonies and their nests are occupied year round by swallow bugs (Oeciacus vicarius, Hovarth), hematophagus ectoparasites that feed primarily on cliff swallows. Swallow bugs are most likely exposed to WNV while feeding on infectious blood of cliff swallows and, thus, if competent vectors, could contribute to initiation and maintenance of seasonal WNV transmission. In addition, swallow bugs remain within nests year round and, therefore, if persistently infected and competent vectors, they could provide an overwintering mechanism for WNV. We tested the hypothesis that swallow bugs become infected with WNV through direct abdominal inoculation or ingestion of infectious blood meals. We observed that swallow bugs did not maintain or amplify WNV, and infectious virus titers within bugs declined over 15 d postexposure. These results suggest that swallow bugs may not be competent vectors of WNV, and therefore are unlikely to play a significant role in transmission.


Asunto(s)
Cimicidae/virología , Virus del Nilo Occidental/fisiología , Animales , Insectos Vectores/virología , Fiebre del Nilo Occidental/transmisión
12.
Br J Ophthalmol ; 104(7): 950-955, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31653669

RESUMEN

BACKGROUND/AIMS: To report the protocol of a trial designed to evaluate the efficacy, safety and mechanism of action of low-dose atropine (0.01%) eye-drops for reducing progression of myopia in UK children. METHODS: Multicentre, double-masked, superiority, placebo-controlled, randomised trial. We will enrol children aged 6-12 years with myopia of -0.50 dioptres or worse in both eyes.We will recruit 289 participants with an allocation ratio of 2:1 (193 atropine; 96 placebo) from five centres. Participants will instil one drop in each eye every day for 2 years and attend a research centre every 6 months. The vehicle and preservative will be the same in both study arms.The primary outcome is SER of both eyes measured by autorefractor under cycloplegia at 2 years (adjusted for baseline). Secondary outcomes include axial length, best corrected distance visual acuity, near visual acuity, reading speed, pupil diameter, accommodation, adverse event rates and allergic reactions, quality of life (EQ-5D-Y) and tolerability at 2 years. Mechanistic evaluations will include: peripheral axial length, peripheral retinal defocus, anterior chamber depth, iris colour, height and weight, activities questionnaire, ciliary body biometry and chorioretinal thickness. Endpoints from both eyes will be pooled in combined analysis using generalised estimating equations to allow for the correlation between eyes within participant. Three years after cessation of treatment, we will also evaluate refractive error and adverse events. CONCLUSIONS: The Childhood Atropine for Myopia Progression in the UK study will be the first randomised trial reporting outcomes of low-dose atropine eye-drops for children with myopia in a UK population. TRIAL REGISTRATION NUMBER: ISRCTN99883695, NCT03690089.


Asunto(s)
Atropina/administración & dosificación , Midriáticos/administración & dosificación , Miopía Degenerativa/tratamiento farmacológico , Administración Oftálmica , Atropina/efectos adversos , Biometría , Niño , Método Doble Ciego , Femenino , Humanos , Masculino , Midriáticos/efectos adversos , Miopía Degenerativa/diagnóstico , Miopía Degenerativa/fisiopatología , Soluciones Oftálmicas/administración & dosificación , Refracción Ocular/fisiología , Encuestas y Cuestionarios , Resultado del Tratamiento , Reino Unido , Agudeza Visual/fisiología
13.
Ecol Appl ; 19(1): 55-68, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19323173

RESUMEN

For the purposes of making many informed conservation decisions, the main goal for data collection is to assess population status and allow prediction of the consequences of candidate management actions. Reducing the bias and variance of estimates of population parameters reduces uncertainty in population status and projections, thereby reducing the overall uncertainty under which a population manager must make a decision. In capture-recapture studies, imperfect detection of individuals, unobservable life-history states, local movement outside study areas, and tag loss can cause bias or precision problems with estimates of population parameters. Furthermore, excessive disturbance to individuals during capture-recapture sampling may be of concern because disturbance may have demographic consequences. We address these problems using as an example a monitoring program for Black-footed Albatross (Phoebastria nigripes) and Laysan Albatross (Phoebastria immutabilis) nesting populations in the northwestern Hawaiian Islands. To mitigate these estimation problems, we describe a synergistic combination of sampling design and modeling approaches. Solutions include multiple capture periods per season and multistate, robust design statistical models, dead recoveries and incidental observations, telemetry and data loggers, buffer areas around study plots to neutralize the effect of local movements outside study plots, and double banding and statistical models that account for band loss. We also present a variation on the robust capture-recapture design and a corresponding statistical model that minimizes disturbance to individuals. For the albatross case study, this less invasive robust design was more time efficient and, when used in combination with a traditional robust design, reduced the standard error of detection probability by 14% with only two hours of additional effort in the field. These field techniques and associated modeling approaches are applicable to studies of most taxa being marked and in some cases have individually been applied to studies of birds, fish, herpetofauna, and mammals.


Asunto(s)
Charadriiformes/fisiología , Ecosistema , Proyectos de Investigación , Animales , Modelos Biológicos , Modelos Estadísticos , Dinámica Poblacional , Tamaño de la Muestra
14.
Environ Manage ; 43(3): 508-13, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18941830

RESUMEN

Southern California desert public lands receive especially high levels of off-highway recreation due to large population centers nearby and popular riding environments such as sand dunes. Controversy has developed over the flat-tailed horned lizard (Phrynosoma mcallii), previously a candidate for listing under the Endangered Species Act. Some evidence suggests lower lizard abundance in areas of higher recreational use than in areas with low or no use. We designed a manipulative experiment to ensure maximum inference in evaluating the direct impact of recreational riding of off-highway vehicles on lizards. Thirty-six lizards, in situ, were treated with an off-highway vehicle treatment during hibernation season in three treatment groups: high impact, low impact, and control. Treatments consisted of timed riding by off-highway vehicles. In all treatment groups survival was 100%, despite hibernation of lizards at very shallow depths. Consequently, indirect effects of off-highway vehicles deserve increased attention. The relative importance of direct versus indirect (i.e., degradation of lizard habitat) impacts caused by off-highway vehicles remains unknown. These indirect effects may include the altering of vegetation, substrate, and prey. We recommend that a manipulative approach be adopted to investigate these possibilities.


Asunto(s)
Conservación de los Recursos Naturales , Lagartos/crecimiento & desarrollo , Recreación , Transportes , Accidentes , Animales , California , Vehículos a Motor Todoterreno , Densidad de Población
15.
BMJ Open ; 9(7): e027951, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31270116

RESUMEN

OBJECTIVES: This study aimed to assess the cost-effectiveness of the Steps Towards Alcohol Misuse Prevention Programme (STAMPP) compared with education as normal (EAN) in reducing self-reported heavy episodic drinking (HED) in adolescents. DESIGN: This is a cost-effectiveness analysis from a public sector perspective conducted as part of a cluster randomised trial. SETTING: This study was conducted in 105 high schools in Northern Ireland and in Scotland. PARTICIPANTS: Students in school year 8/S1 (aged 11-12) at baseline were included in the study. INTERVENTIONS: This is a classroom-based alcohol education curricula, combined with a brief alcohol intervention for parents/carers. OUTCOME MEASURES: The outcome of this study is the cost per young person experiencing HED avoided due to STAMPP at 33 months from baseline. RESULTS: The total cost of STAMPP was £85 900, equivalent to £818 per school and £15 per pupil. Due to very low uptake of the parental component, we calculated costs of £692 per school and £13 per pupil without this element. Costs per pupil were reduced further to £426 per school and £8 per pupil when it was assumed there were no additional costs of classroom delivery if STAMPP was delivered as part of activities such as personal, social, health and economic education. STAMPP was associated with a significantly greater proportion of pupils experiencing a heavy drinking episode avoided (0.08/8%) and slightly lower public sector costs (mean difference -£17.19). At a notional willingness-to-pay threshold of £15 (reflecting the cost of STAMPP), the probability of STAMPP being cost-effective was 56%. This level of uncertainty reflected the substantial variability in the cost differences between groups. CONCLUSIONS: STAMPP was relatively low cost and reduced HED. STAMPP was not associated with any clear public sector cost savings, but neither did it increase them or lead to any cost-shifting within the public sector categories. Further research is required to establish if the cost-effectiveness of STAMPP is sustained in the long term. TRIAL REGISTRATION NUMBER: ISRCTN47028486; Results.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/prevención & control , Curriculum , Promoción de la Salud/métodos , Servicios de Salud Escolar/economía , Adolescente , Consumo Excesivo de Bebidas Alcohólicas/epidemiología , Niño , Análisis Costo-Beneficio , Femenino , Promoción de la Salud/economía , Humanos , Masculino , Irlanda del Norte/epidemiología , Padres , Evaluación de Programas y Proyectos de Salud , Años de Vida Ajustados por Calidad de Vida , Asunción de Riesgos , Escocia/epidemiología , Autoinforme , Estudiantes
16.
BMJ Open ; 8(3): e019722, 2018 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-29525770

RESUMEN

OBJECTIVES: To assess the effectiveness of a combined classroom curriculum and parental intervention (the Steps Towards Alcohol Misuse Prevention Programme (STAMPP)), compared with alcohol education as normal (EAN), in reducing self-reported heavy episodic drinking (HED) and alcohol-related harms (ARHs) in adolescents. SETTING: 105 high schools in Northern Ireland (NI) and in Scotland. PARTICIPANTS: Schools were stratified by free school meal provision. Schools in NI were also stratified by school type (male/female/coeducational). Eligible students were in school year 8/S1 (aged 11-12 years) at baseline (June 2012). INTERVENTION: A classroom-based alcohol education intervention, coupled with a brief alcohol intervention for parents/carers. PRIMARY OUTCOMES: (1) The prevalence of self-reported HED in the previous 30 days and (2) the number of self-reported ARHs in the previous 6 months. Outcomes were assessed using two-level random intercepts models (logistic regression for HED and negative binomial for number of ARHs). RESULTS: At 33 months, data were available for 5160 intervention and 5073 control students (HED outcome), and 5234 and 5146 students (ARH outcome), respectively. Of those who completed a questionnaire at either baseline or 12 months (n=12 738), 10 405 also completed the questionnaire at 33 months (81.7%). Fewer students in the intervention group reported HED compared with EAN (17%vs26%; OR=0.60, 95% CI 0.49 to 0.73), with no significant difference in the number of self-reported ARHs (incident rate ratio=0.92, 95% CI 0.78 to 1.05). Although the classroom component was largely delivered as intended, there was low uptake of the parental component. There were no reported adverse effects. CONCLUSIONS: Results suggest that STAMPP could be an effective programme to reduce HED prevalence. While there was no significant reduction in ARH, it is plausible that effects on harms would manifest later. TRIAL REGISTRATION NUMBER: ISRCTN47028486; Post-results.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/prevención & control , Promoción de la Salud/métodos , Servicios de Salud Escolar/estadística & datos numéricos , Adolescente , Consumo Excesivo de Bebidas Alcohólicas/epidemiología , Niño , Servicios de Salud Comunitaria/estadística & datos numéricos , Femenino , Humanos , Análisis de Intención de Tratar , Estudios Longitudinales , Masculino , Irlanda del Norte/epidemiología , Padres , Evaluación de Programas y Proyectos de Salud , Asunción de Riesgos , Escocia/epidemiología , Autoinforme , Método Simple Ciego , Estudiantes
17.
PLoS One ; 12(10): e0185890, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29016633

RESUMEN

Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-lined Tanager (Tachyphonus rufus) using capture-mark-recapture data from northeastern Brazil. We tested whether survival varied seasonally (breeding vs. non-breeding), with rainfall, by age and residence status in our study area. Intra-annual apparent survival was correlated with the reproductive cycle, being lower during the breeding (0.65 ± 0.16 SE) vs. the non-breeding season (0.97 ± 0.05 SE). The annual apparent survival (~0.6) was relatively low for a tropical species. In both years, we observed highest abundance in spring (November, 3.1-3.7 birds/ha) and lowest abundance in autumn-winter periods (May-August, 1.1-1.4 bird/ha). The low survival during the breeding season probably reflects the trade-off between survival and reproduction and the cost of reproduction. Our findings represent an advance in the understanding of the demography of tropical birds because we did not find a predicted high annual apparent survival, and we elucidated some aspects of intra-annual variation in survival. Further exploration of latitudinal variation in demographic traits, especially in diverse, but poorly known habitats is needed to fully vet and develop life history theories.


Asunto(s)
Longevidad/fisiología , Passeriformes/fisiología , Reproducción/fisiología , Distribución Animal/fisiología , Animales , Brasil , Femenino , Masculino , Lluvia , Bosque Lluvioso , Estaciones del Año
19.
Front Vet Sci ; 3: 123, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28119919

RESUMEN

Maintaining high vaccination coverage is key to successful rabies control, but mass dog vaccination can be challenging and population turnover erodes coverage. Declines in rabies incidence following successive island-wide vaccination campaigns in Bali suggest that prospects for controlling and ultimately eliminating rabies are good. Rabies, however, has continued to circulate at low levels. In the push to eliminate rabies from Bali, high coverage needs to be maintained across all areas of the island. We carried out door-to-door (DTD) questionnaire surveys (n = 10,352 dog-owning households) and photographic mark-recapture surveys (536 line transects, 2,597 observations of free-roaming dogs) in 2011-2012 to estimate dog population sizes and assess rabies vaccination coverage and dog demographic characteristics in Bali, Indonesia. The median number of dogs per subvillage unit (banjar) was 43 (range 0-307) for owned dogs estimated from the DTD survey and 17 (range 0-83) for unconfined dogs (including both owned and unowned) from transects. Vaccination coverage of owned dogs was significantly higher in adults (91.4%) compared to juveniles (<1 year, 43.9%), likely due to insufficient targeting of pups and from puppies born subsequent to vaccination campaigns. Juveniles had a 10-70 times greater risk of not being vaccinated in urban, suburban, and rural areas [combined odds ratios (ORs): 9.9-71.1, 95% CI: 8.6-96.0]. Free-roaming owned dogs were also 2-3 times more likely to be not vaccinated compared to those confined (combined Ors: 1.9-3.6, 95% CI: 1.4-5.4), with more dogs being confined in urban (71.2%) than in suburban (16.1%) and rural areas (8.0%). Vaccination coverage estimates from transects were also much lower (30.9%) than household surveys (83.6%), possibly due to loss of collars used to identify the vaccination status of free-roaming dogs, but these unconfined dogs may also include dogs that were unowned or more difficult to vaccinate. Overall, coverage levels were high in the owned dog population, but for future campaigns in Bali to have the highest chance of eliminating rabies, concerted effort should be made to vaccinate free-roaming dogs particularly in suburban and rural areas, with advertising to ensure that owners vaccinate pups. Long-lasting, cheap, and quick methods are needed to mark vaccinated animals and reassure communities of the reach of vaccination campaigns.

20.
PLoS One ; 10(8): e0136310, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26287996

RESUMEN

Gunnison Sage-Grouse (Centrocercus minimus) is a species of concern for which little demographic information exists. To help fill this information gap, we investigated factors affecting nest success in two populations of Gunnison Sage-Grouse. We assessed the relative effects of (1) vegetation characteristics (e.g., shrub height, shrub cover, grass cover, and grass height), (2) temporal factors (e.g., year, timing of incubation initiation, and nest age), (3) precipitation, and (4) age of the nesting female (yearling or adult) on nest success rates. We found 177 nests in the Gunnison Basin population (that contains 85-90% of the species) from 2005-2010 and 20 nests in the San Miguel population (that contains < 10% of the species) from 2007-2010. Temporal factors had the greatest impact on nest success compared to vegetation characteristics, precipitation, and female age. Nest success varied considerably among years ranging from 4.0%-60.2% in Gunnison Basin and from 12.9%- 51.9% in San Miguel. Nests that were initiated earlier in the breeding season had higher nest success (at least one egg hatches). Daily nest survival rates decreased during the course of incubation. None of the vegetation characteristics we examined were strongly related to nest success.


Asunto(s)
Galliformes/fisiología , Animales , Colorado , Ecosistema , Femenino , Modelos Biológicos , Comportamiento de Nidificación/fisiología , Dinámica Poblacional , Estaciones del Año
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