836 research outputs found
Retrieval effectiveness of written and spoken queries : an experimental evaluation
With the fast growing speech technologies, the world is emerging to a new speech era. Speech recognition has now become a practical technology for real world applications. While some work has been done to facilitate retrieving information in speech format using textual queries, the characteristics of speech as a way to express an information need has not been extensively studied. If one compares written versus spoken queries, it is intuitive to think that users would issue longer spoken queries than written ones, due to the ease of speech. Is this in fact the case in reality? Also, if this is the case, would longer spoken queries be more effective in helping retrieving relevant document than written ones? This paper presents some new findings derived from an experimental study to test these intuitions
Associations with Retinal Pigment Epithelium Thickness Measures in a Large Cohort: Results from the UK Biobank
PURPOSE: To describe associations of ocular and systemic factors with retinal pigment epithelium (RPE)-Bruch's membrane (BM) complex thickness as measured by spectral-domain (SD) optical coherence tomography (OCT). DESIGN: Multisite community-based study. This research has been conducted using the UK Biobank Resource. PARTICIPANTS: Sixty-seven thousand three hundred eighteen people 40 to 69 years old received questionnaires, physical examination, and eye examination, including macular SD OCT. Systematic selection process identified 34 652 eyes with high-quality SD OCT images from normal individuals for analysis. METHODS: We included people with no self-reported ocular disease, diabetes, or neurologic disorders; visual acuity of ≥20/25; refraction between -6 diopters (D) to 6 D, and IOP of 6 to 21 mmHg. Only high-quality, well-centered SD OCT images with central, stable fixation were included. Descriptive statistics, t tests, and regression analyses were performed. Multivariate regression modeling was used to adjust for covariates and to identify relationships between RPE-BM thickness and ocular and systemic features. MAIN OUTCOME MEASURES: Retinal pigment epithelium-BM thickness, as measured by SD OCT segmentation using Topcon Advanced Boundary Segmentation at 9 Early Treatment of Diabetic Retinopathy Study subfields. RESULTS: Mean RPE-BM thickness was 26.3 μm (standard deviation, 4.8 μm) at central subfield. Multivariate regression with age stratification showed that RPE thinning became apparent after age 45. Among those aged ≤45, RPE-BM was significantly thicker among those of black or mixed/other race (+3.61 and +1.77 μm vs. white, respectively; P 45, RPE-BM was significantly thinner with older age (-0.10 μm/year; P < 0.001), Asian ethnicity (-0.45 μm vs. white; P = 0.02), taller height (-0.02 μm/cm; P < 0.001), higher IOP (-0.03 μm/mmHg; P < 0.001), and regular smoking (-0.27 μm vs. nonsmokers; P = 0.02). In contrast, RPE-BM was significantly thicker among black or mixed/other race (+3.29 μm and +0.81 μm vs. white, respectively; P < 0.001) and higher hyperopia (+0.28 μm/D; P < 0.001). There was no significant association with sex or Chinese ethnicity. CONCLUSIONS: We describe novel findings of RPE-BM thickness in normal individuals, a structure that varies with age, ethnicity, refraction, IOP, and smoking. The significant association with IOP is especially interesting and may have relevance for the etiology of glaucoma, while the association between age and smoking may have relevance for the etiology of age-related macular degeneration
Simulation Modelling in Ophthalmology : Application to Cost Effectiveness of Ranibizumab and Aflibercept for the Treatment of Wet Age-Related Macular Degeneration in the United Kingdom
Previously developed models in ophthalmology have generally used a Markovian structure. There are a number of limitations with this approach, most notably the ability to base patient outcomes on best-corrected visual acuity (BCVA) in both eyes, which may be overcome using a different modelling structure. Simulation modelling allows for this to be modelled more precisely, and therefore may provide more accurate and relevant estimates of the cost effectiveness of ophthalmology interventions
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The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group, Report 1: baseline characteristics and visual acuity outcomes in eyes treated with intravitreal injections of ranibizumab for diabetic macular oedema
Aims: To describe baseline characteristics and visual outcome for eyes treated with ranibizumab for diabetic macular oedema (DMO) from a multicentre database.
Methods: Structured clinical data were anonymised and extracted from an electronic medical record from 19 participating UK centres: age at first injection, ETDRS visual acuity (VA), number of injections, ETDRS diabetic retinopathy (DR) and maculopathy grade at baseline and visits. The main outcomes were change in mean VA from baseline, number of injections and clinic visits and characteristics affecting VA change and DR grade.
Results: Data from 12 989 clinic visits was collated from baseline and follow-up for 3103 eyes. Mean age at first treatment was 66 years. Mean VA (letters) for eyes followed at least 2 years was 51.1 (SD=19.3) at baseline, 54.2 (SD: 18.6) and 52.5 (SD: 19.4) at 1 and 2 years, respectively. Mean visual gain was five letters. The proportion of eyes with VA of 72 letters or better was 25% (baseline) and 33% (1 year) for treatment naïve eyes. Eyes followed for at least 6 months received a mean of 3.3 injections over a mean of 6.9 outpatient visits in 1 year.
Conclusions: In a large cohort of eyes with DMO treated with ranibizumab injections in the UK, 33% of patients achieved better than or equal to 6/12 in the treated eye at 12 months compared with 25% at baseline. The mean visual gain was five letters. Eyes with excellent VA at baseline maintain good vision at 18 months
Spontaneous retinal pigment epithelial tear in type 2 choroidal neovascularization: Repair mechanisms following anti-VEGF therapy
BACKGROUND:
To report the clinical course and the multimodal retinal imaging of a spontaneous retinal pigment epithelial (RPE) tear in a type 2 choroidal neovascularization (CNV) secondary to age-related macular degeneration treated with anti-vascular endothelial growth factor (VEGF) treatment.
CASE PRESENTATION: A 74 year-old man presented with visual acuity deterioration in the right eye. Multimodal retinal imaging showed a predominantly classic (type 2) CNV complicated by a spontaneous RPE tear. The patient received six intravitreal injections of anti-VEGF which resulted in improvement of the vision and stabilization of the neovascular lesion on optical coherence tomography (OCT). Longitudinal changes of the RPE-photoreceptors interface, including RPE splitting, are reported on OCT.
CONCLUSION:
RPE tears may spontaneously occur in type 2 CNV. Anti-VEGF treatment should be aimed at promoting RPE repair and limiting the extent of the scarring. The mechanisms of RPE repair during treatment may be documented with OCT
MicroRNAs in pulmonary arterial remodeling
Pulmonary arterial remodeling is a presently irreversible pathologic hallmark of pulmonary arterial hypertension (PAH). This complex disease involves pathogenic dysregulation of all cell types within the small pulmonary arteries contributing to vascular remodeling leading to intimal lesions, resulting in elevated pulmonary vascular resistance and right heart dysfunction. Mutations within the bone morphogenetic protein receptor 2 gene, leading to dysregulated proliferation of pulmonary artery smooth muscle cells, have been identified as being responsible for heritable PAH. Indeed, the disease is characterized by excessive cellular proliferation and resistance to apoptosis of smooth muscle and endothelial cells. Significant gene dysregulation at the transcriptional and signaling level has been identified. MicroRNAs are small non-coding RNA molecules that negatively regulate gene expression and have the ability to target numerous genes, therefore potentially controlling a host of gene regulatory and signaling pathways. The major role of miRNAs in pulmonary arterial remodeling is still relatively unknown although research data is emerging apace. Modulation of miRNAs represents a possible therapeutic target for altering the remodeling phenotype in the pulmonary vasculature. This review will focus on the role of miRNAs in regulating smooth muscle and endothelial cell phenotypes and their influence on pulmonary remodeling in the setting of PAH
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The UK Diabetic Retinopathy Electronic Medical Record (UK DR EMR) Users Group, Report 2: real-world data for the impact of cataract surgery on diabetic macular oedema
Aim: To assess the rate of ‘treatment-requiring diabetic macular oedema (DMO)’ in eyes for the two years before and after cataract surgery.
Methods: Multicentre national diabetic retinopathy (DR) database study with anonymised data extraction across 19 centres from an electronic medical record system. Inclusion criteria: eyes undergoing cataract surgery in patients with diabetes with no history of DMO prior to study start. The minimum dataset included: age, visual acuity (all time-points), injection episodes, timing of cataract surgery and ETDRS grading of retinopathy and maculopathy. Main outcome measure: rate of developing first episode of treatment-requiring DMO in relation to timing of cataract surgery in the same eye.
Results: 4850 eyes met the inclusion criteria. The rate of developing treatment-requiring DMO in this cohort was 2.9% in the year prior to surgery versus 5.3% in the year after surgery (p<0.01). The risk of ‘treatment-requiring DMO’ increased sharply after surgery, peaking in the 3–6 months' period (annualised rates of 5.2%, 6.8%, 5.6% and 4.0% for the 0–3, 3–6, 6–9 and 9–12 months' post-operative time periods respectively). Risk was associated with pre-operative grade of retinopathy: risk of DMO in the first year post-operatively being 1.0% (no DR pre-operatively), 5.4% (mild non-proliferative diabetic retinopathy; NPDR), 10.0% (moderate NPDR), 13.1% (severe NPDR) and 4.9% (PDR) (p<0.01).
Conclusions: This large real-world study demonstrates that the rate of developing treatment-requiring DMO increases sharply in the year after cataract surgery for all grades of retinopathy, peaking in the 3–6 months' postoperative period. Patients with moderate and severe NPDR are at particularly high risk
Peripheral blood mononuclear cells from neovascular age-related macular degeneration patients produce higher levels of chemokines CCL2 (MCP-1) and CXCL8 (IL-8)
Flow cytometry analysis of PBMCs. PBMCs were first divided into CD11b+CD3−, CD11b−CD3+ and CD11b−CD3− cells (A) and the average percentage of all samples (n = 55) was analysed before and after stimulation with PMA/ionomycin (B). Figure S2. Percentage of total IL-4 and IL-10 producing PBMCs and percentage of CD11b−CD3+ IL-17A and IFNγ producing PBMCs (almost all of IL-17A and IFNγ producing PBMCs were CD11b−CD3+) from controls and nAMD patients under non-stimulated culture conditions and after stimulation with PMA/ionomycin. Controls n = 27, nAMD = 28; mean + SEM are shown. (PDF 413 kb
Objective structured practical examination (OSPE) as a tool in formative assessment of II MBBS students, in pathology
Background: Assessment drives the student learning. Regular periodical assessment not only improves learning habits, but also enhances the competence in all levels of medical education. Traditional practical examination is more subjective. It depends on examiners subjectivity, varying difficulty level of various experiments, and also internal marks variation etc. These flaws can be overcome by newer methods like OSPE. The aim of the study was to implement OSPE as a tool of internal assessment for practical skills in the II MBBS. To compare this with traditional practical examination (TPE). To obtain the students and faculty feedback regarding OSPE as a tool of assessment.Methods: A cross sectional study was carried out for 158 students in II internal pathology practical examination for six days in the second week of September 2016 at Department of Pathology, Dr. Pinnamaneni Siddhartha institute of medical sciences & Research Foundation, Chinnaoutpalli. Faculty and students were sensitized; blueprint were used to arrange twenty OSPE stations for the exercises conducted as per TPE and for the same 25 marks as per TPE. Simultaneously, all the students were subjected to both TPE and OSPE at the same time and venue. TPE was assessed by two professors and OSPE by separate eight faculty members independently without interaction with the students. The procedural stations were evaluated by using checklist and the response stations which consisted of short answers and MCQs, facilitated correction. Feedback was given to the student on their performance and feedback was obtained from the students and faculty regarding OSPE by questionnaire with Yes/No answers.Results: Performance score of students in OPSE (13.73 ±2.49) was higher as compared to TPE (9.27±1.86) which was statistically significant. Based on the response to the questionnaire, students perception towards OSPE was analyzed. Majority strongly agree OSPE to be fairer, more transparent and objective in comparison to TPE. In contrast, all the faculty members unanimously opined that OSPE was difficult to arrange, time taken and faculty versus students ratio was high for evaluation. Though, the faculty (91%) overall opined that OSPE should be included as a method of assessment.Conclusions: Present study revealed that OSPE was acceptable, feasible and reliable to the students as well as for faculty for the internal assessment in pathology. Opinions of both students and faculties strongly agreed that OPSE is more effective objective assessment tool
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