| 1. |
- Bravo, L, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
- Tabiri, S, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 3. |
- Khatri, C, et al.
(författare)
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Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
- 2021
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Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
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Tidskriftsartikel (refereegranskat)abstract
- Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
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| 4. |
- Ikuta, K. S., et al.
(författare)
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Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019
- 2022
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Ingår i: Lancet. - : Elsevier BV. - 0140-6736. ; 400:10369, s. 2221-2248
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Tidskriftsartikel (refereegranskat)abstract
- Background Reducing the burden of death due to infection is an urgent global public health priority. Previous studies have estimated the number of deaths associated with drug-resistant infections and sepsis and found that infections remain a leading cause of death globally. Understanding the global burden of common bacterial pathogens (both susceptible and resistant to antimicrobials) is essential to identify the greatest threats to public health. To our knowledge, this is the first study to present global comprehensive estimates of deaths associated with 33 bacterial pathogens across 11 major infectious syndromes. Methods We estimated deaths associated with 33 bacterial genera or species across 11 infectious syndromes in 2019 using methods from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, in addition to a subset of the input data described in the Global Burden of Antimicrobial Resistance 2019 study. This study included 343 million individual records or isolates covering 11 361 study-location-years. We used three modelling steps to estimate the number of deaths associated with each pathogen: deaths in which infection had a role, the fraction of deaths due to infection that are attributable to a given infectious syndrome, and the fraction of deaths due to an infectious syndrome that are attributable to a given pathogen. Estimates were produced for all ages and for males and females across 204 countries and territories in 2019. 95% uncertainty intervals (UIs) were calculated for final estimates of deaths and infections associated with the 33 bacterial pathogens following standard GBD methods by taking the 2.5th and 97.5th percentiles across 1000 posterior draws for each quantity of interest. Findings From an estimated 13.7 million (95% UI 10.9-17.1) infection-related deaths in 2019, there were 7.7 million deaths (5.7-10.2) associated with the 33 bacterial pathogens (both resistant and susceptible to antimicrobials) across the 11 infectious syndromes estimated in this study. We estimated deaths associated with the 33 bacterial pathogens to comprise 13.6% (10.2-18.1) of all global deaths and 56.2% (52.1-60.1) of all sepsis-related deaths in 2019. Five leading pathogens-Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Klebsiella pneumoniae, and Pseudomonas aeruginosa-were responsible for 54.9% (52.9-56.9) of deaths among the investigated bacteria. The deadliest infectious syndromes and pathogens varied by location and age. The age-standardised mortality rate associated with these bacterial pathogens was highest in the sub-Saharan Africa super-region, with 230 deaths (185-285) per 100 000 population, and lowest in the high-income super-region, with 52.2 deaths (37.4-71.5) per 100 000 population. S aureus was the leading bacterial cause of death in 135 countries and was also associated with the most deaths in individuals older than 15 years, globally. Among children younger than 5 years, S pneumoniae was the pathogen associated with the most deaths. In 2019, more than 6 million deaths occurred as a result of three bacterial infectious syndromes, with lower respiratory infections and bloodstream infections each causing more than 2 million deaths and peritoneal and intra-abdominal infections causing more than 1 million deaths. Interpretation The 33 bacterial pathogens that we investigated in this study are a substantial source of health loss globally, with considerable variation in their distribution across infectious syndromes and locations. Compared with GBD Level 3 underlying causes of death, deaths associated with these bacteria would rank as the second leading cause of death globally in 2019; hence, they should be considered an urgent priority for intervention within the global health community. Strategies to address the burden of bacterial infections include infection prevention, optimised use of antibiotics, improved capacity for microbiological analysis, vaccine development, and improved and more pervasive use of available vaccines. These estimates can be used to help set priorities for vaccine need, demand, and development. Copyright (c) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.
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| 5. |
- Bryazka, D., et al.
(författare)
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Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020
- 2022
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Ingår i: Lancet. - 0140-6736. ; 400:10347, s. 185-235
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Tidskriftsartikel (refereegranskat)abstract
- Background The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods For this analysis, we constructed burden-weighted dose-response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15-95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15-39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0-0) and 0.603 (0.400-1.00) standard drinks per day, and the NDE varied between 0.002 (0-0) and 1.75 (0.698-4.30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0.114 (0-0.403) to 1.87 (0.500-3.30) standard drinks per day and an NDE that ranged between 0.193 (0-0.900) and 6.94 (3.40-8.30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59.1% (54.3-65.4) were aged 15-39 years and 76.9% (7.0-81.3) were male. Interpretation There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd.
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| 11. |
- Chekitaan, S, et al.
(författare)
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The results of treatment of anisomyopic and anisohypermetropic amblyopia
- 2008
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Ingår i: International ophtalmology. - : Springer Science and Business Media LLC. - 0165-5701 .- 1573-2630. ; 29:4, s. 231-237
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Tidskriftsartikel (refereegranskat)abstract
- Purpose To analyze the results of treatment of anisomyopic and anisohypermetropic amblyopia comparing full-time and part-time occlusion. Methods Retrospective analysis of case records of 100 patients of anisometropic amblyopia was carried out. Age, visual acuity, cycloplegic refraction, response, and compliance to treatment were recorded. Full-time occlusion (FTO) or part-time occlusion (PTO) was prescribed as treatment. Results The age of children ranged from 4 to 13 years (mean 7.65 years). In total, 66% of the patients were anisomyopic and 34% were anisohypermetropic. FTO was prescribed in 64 (64%), PTO in 29 (29%). Follow-up ranged from 1 to 24 months. The paired t-test revealed significant improvement of mean visual acuity in the FTO group (t = 13.272) compared with the PTO group (t = 7.386). A final visual acuity of 6/9 or better was achieved by 51% (34/66) anisomyopic amblyopes and 52% (18/34) anisohypermetropic amblyopes. Noncompliance to the treatment was 21%. Occlusion amblyopia was seen in four (4%) of the children. Conclusion FTO is superior to PTO for the treatment of amblyopia. The greatest amount of improvement in visual acuity was seen in simple myopes and the least in simple hyperopes. Compliance is critical for successful treatment of amblyopia.
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| 12. |
- Alahamami, Mastour A., et al.
(författare)
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Comparison of cysts in red and green images for diabetic macular edema
- 2014
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Konferensbidrag (refereegranskat)abstract
- Purpose: To improve the detection of macular cyst with photoscreening, we tested whether in a population of largely minority patients the red channel image from a color fundus camera visualizes cysts in diabetic macular edema better than the green channel image. In assessing diabetic retinas for clinically significant macular edema, the presence of cysts must be judged with respect to the central macula. Some grading programs use red free images, often derived from green channel images, to enhance visualization of retinal vessel damage or macular pigment, but some red and near infrared instruments have detected cysts better than short wavelength techniques. Methods: We evaluated macular cysts in 13 diabetic patients diagnosed with clinically significant macular edema, age range 33-68 years. Diabetic patients were selected from the screening study of >2000 underserved patients seen at Eastmont Wellness Center, Oakland, CA. Patients underwent photoscreening with a nonmydriatic color fundus camera (Canon Cr-DGi, Tokyo, Japan) and SD-OCT (iVue, Optovue Inc, Fremont, CA). The color fundus images for those patients were transformed into red and green channels to evaluate the appearance of macular cysts in red channel images and green channel images. The region of each cyst was compared SD-OCT scans (Adobe Photoshop CS5.1, San Jose, CA). Only cysts touching the central 1 mm around the fixation from the SD-OCT scans were sampled. Results: The average size of retinal cysts in red channel images, 124.57 µm (±106.96), was significantly greater than in green channel, 59.44 µm (±76.6), (p<0.006). Entire cysts could not be seen in 5 eyes in the green channel images. Conclusions: Our results indicate that the grading of cysts in the central macular might be improved by incorporating red channel images. There are a number of potential factors that could make cysts less visible in the green channel images, including poorer light penetration through to the deeper retina or macular pigment. Anterior segment issues impact more on green channel images. This population includes mostly minority patients who have dark fundi, and darker images.
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| 13. |
- Alahamami, Mastour A., et al.
(författare)
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Investigation of Photoreceptors in Diabetic Macular Edema
- 2014
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Ingår i: IOVS. - Orlando, Florida, USA.
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Konferensbidrag (refereegranskat)abstract
- Abstract Purpose: To evaluate the photoreceptor integrity in diabetic patients with macular edema using spectral domain optical coherence tomography (SD-OCT) Methods: We compared macular thickness in diabetic patients with and without macular edema to determine the role of damage to the external limiting membrane (ELM) or photoreceptors. Diabetic patients were selected from the screening study of > 2000 minority patients seen at Eastmont Wellness Center, Oakland, CA. Patients underwent photoscreening with a Canon Cr-DGi nonmydriatic camera (Tokyo, Japan) and an iVue OCT (Optovue Inc, Fremont, CA). Retinal scans of 70 diabetic patients, age range 33-68 yr., were selected so that A) 50% of patients had clinical significant macular edema (CSME), as diagnosed by the presence of hard exudates within 1 disc diameter from the fovea in the color photos, B) the full range of central macular thicknesses in our population was included. And C) patients with CSME were the same age as those not diagnosed with CSME. We graded the retinal scans according to the external limiting membrane (ELM) integrity; 6 patients had damaged ELM and the remaining 64 had intact ELM. Similarly, we graded the retinal scans according to the photoreceptor integrity; 14 patients had damaged photoreceptors and the remaining 56 had intact photoreceptors Results: Average retinal thickness was 254 µm (±57.4) and 356 µm (±95.9) in patients with intact and damaged ELM, respectively; and was 240 µm (±30.0), and 363 µm (±90.0) in patients with intact and damaged photoreceptors, respectively. Retinal thickness means were significantly greater for patients with damaged compared with intact ELM ( P=0.031). Similarly, Retinal thickness means in patients with damaged photoreceptors were significantly greater compared to patients with intact photoreceptors ( P = 0.0001). We also observed that all 6 patients who have damaged ELM were diagnosed with CSME, but were not significantly older than the diabetic patients not diagnosed with CSME ( P = 0.393) Conclusions: ELM and photoreceptor layer damage are found more often when retinal thickness exceeds 355 µm. It is not known if this outer retinal damage is the result of the edema or whether there is more edema because the outer retinal blood brain barrier is failing
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| 14. |
- Arthur, Edmund, et al.
(författare)
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Central Macular Thickness in Diabetic Patients : A Sex-based Analysis
- 2019
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Ingår i: Optometry and Vision Science. - : American Academy of Optometry. - 1040-5488 .- 1538-9235. ; 96:4, s. 266-275
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Tidskriftsartikel (refereegranskat)abstract
- SIGNIFICANCE The pathological changes in clinically significant diabetic macular edema lead to greater retinal thickening in men than in women. Therefore, male sex should be considered a potential risk factor for identifying individuals with the most severe pathological changes. Understanding this excessive retinal thickening in men may help preserve vision. PURPOSE The purpose of this study was to investigate the sex differences in retinal thickness in diabetic patients. We tested whether men with clinically significant macular edema had even greater central macular thickness than expected from sex differences without significant pathological changes. This study also aimed to determine which retinal layers contribute to abnormal retinal thickness. METHODS From 2047 underserved adult diabetic patients from Alameda County, CA, 142 patients with clinically significant macular edema were identified by EyePACS-certified graders using color fundus images (Canon CR6-45NM). First, central macular thickness from spectral domain optical coherence tomography (iVue; Optovue Inc.) was compared in 21 men versus 21 women without clinically significant macular edema. Then, a planned comparison contrasted the greater values of central macular thickness in men versus women with clinically significant macular edema as compared with those without. Mean retinal thickness and variability of central macular layers were compared in men versus women. RESULTS Men without clinically significant macular edema had a 12-μm greater central macular thickness than did women (245 ± 21.3 and 233 ± 13.4 μm, respectively; t40 = −2.18, P = .04). Men with clinically significant macular edema had a 67-μm greater central macular thickness than did women (383 ± 48.7 and 316 ± 60.4 μm, P < .001); that is, men had 55 μm or more than five times more (t20 = 2.35, P = .02). In men, the outer-nuclear-layer thickness was more variable, F10,10 = 9.34. CONCLUSIONS Underserved diabetic men had thicker retinas than did women, exacerbated by clinically significant macular edema.
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| 15. |
- Arthur, Edmund, et al.
(författare)
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Individual Retinal Layer Thickness in Diabetic Patients with Clinically Significant Macular Edema : A Gender Based Analysis
- 2016
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Konferensbidrag (refereegranskat)abstract
- Purpose: To compare segmented retinal layer thicknesses between male and female diabetics with clinically significant macular edema (CSME). This study expands our earlier analysis of central macular thickness (CMT) measurements in diabetic males vs. females. Methods: Diabetic retinopathy screening of 2080 diabetics from Alameda County, CA, indicated 142 patients with CSME, as judged by EyePACS certified graders using color fundus images (Canon CR6-45NM). Of the 2080 diabetics, 1784 were imaged with SD-OCT (Optovue iVue). From the 142 patients, we selected 11 males with good fixation, CMT > 300 µm, and no other ocular complications, along with 11 females with the greatest values of CMT while controlling for age, HbA1c and diabetes duration. Manual segmentation of retinal layers using custom software (Mathworks Matlab) of the SD-OCT images of these subjects was done. We analyzed thicknesses for regions 1 deg - 2 deg for nasal and temporal retina in a B-scan centered on the fovea. A 2 X 2 ANOVA probed the differences in thickness for gender, meridian, and their interaction. We also analyzed the central 1 mm of the outer retinal layers, and performed t-tests. Results: Males had significantly thicker nerve fiber layer (NFL) (13.30 ± 2.85 µm) than females (10.13 ± 6.13 µm) and ganglion cell layer-inner plexiform layer (GCL-IPL) (62.54 ± 21.18 µm) than females (48.07 ± 25.91 µm), p < 0.05. There was no effect of meridian and no interaction (p > 0.05). All other layers except the retinal pigment epithelium (RPE) were thicker for males than females even though these were not significant (p > 0.05). There were no significant differences for the layers of the outer retina, which were highly variable and distorted by cysts. Conclusion: Outside the fovea, NFL and GCL-IPL thicknesses were significantly higher in males than females.
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| 16. |
- Baskaran, Karthikeyan, et al.
(författare)
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Stability of fixation in diabetes patients with and without clinically significant macular edema
- 2014
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Konferensbidrag (refereegranskat)abstract
- Purpose - Eye diseases affecting central vision impair fixation and interfere with day-to-day tasks such as reading. Diabetic retinopathy and clinically significant macular edema (CSME) are leading causes of visual impairment in diabetes patients. The aim of this study is to find whether diabetic patients with CSME have poorer fixation stability compared to patients without CSME, by analyzing the fundus images obtained from the Laser Scanning Digital Camera (LSDC).Methods - Two hundred underserved, diabetic patients were screened for diabetic retinopathy at the Eastmont Wellness Center within the EyePACS telemedicine network, using LSDC. One eye of each patient who had diabetic retinopathy was included in this study. Non-mydriatic color fundus photos were classified for presence of CSME by two independent, certified EyePACS graders. The first 50 patients (25 males & 25 females) with CSME were selected and 50 (27 males & 23 females) diabetic patients without CSME were selected as controls. Mean age was 59 (±9) years for patients with CSME and was 55 (±10) years for patients without CSME. The subjects included 53% Hispanics, 26% African Americans and 21% other. A series of 20 images (36 deg field, 1024 X 1024 pixels, and 850 nm) were acquired at 11 fps. Eye positions were obtained by selecting a region of interest in the first image of each series and aligning the remaining images to that region by cross-correlation. The bi-contour ellipse area (BCEA) and the standard deviation of the Euclidean distance (SDED) were used to quantify fixation stability.Results - The fixation stability for patients with CSME was significantly worse than for those without CSME (t test: p < 0.001, 0.007 for BCEA and SDED, respectively). The mean fixation stability obtained by the BCEA metric was 2.74 (±0.40) log(minArc2) and 2.34 (±0.42) log(minArc2) for patients with and without CSME, respectively. For SDED the mean was 48.4 (±28.8) microns and 34.6 (±20.4) microns for patients with and without CSME, respectively. The correlation with age was not significant for either group (R2 = 0.052, 0.011).Conclusions - Diabetic patients with CSME had poorer fixation stability than patients without CSME for both metrics. Fixation stability is a potential tool for assessing macular function and could be used for tracking the treatment and progression of macular edema.The LSDC images provide one method to quantify fixation stability rapidly.
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| 17. |
- Elsner, Ann E., et al.
(författare)
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Underserved diabetic patients with refractive errors insufficient to lead to seeking eyecare
- 2015
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Konferensbidrag (refereegranskat)abstract
- Purpose: The increase in prevalence of diabetes is anticipated to increase the numbers of patients needing eye examinations. For our Phase II SBIR data, we reported that for > 2000 underserved diabetic patients in Alameda County, California, > 60% of patients reported no eye examination for at least 3 years despite that free photo diabetic retinopathy screenings were offered with follow on examination and eyecare. If eye screening for diabetic patients is not mandated, it becomes the responsibility of the patient or their primary care physician or endocrinologist to understand and act on the need for eye examinations. Methods: From the Alameda Health system of clinics, 197 diabetic patients agreed to be photoscreened for diabetic retinopathy. Our sample was enriched to have an increased probability of eye complications; thus, 26% had no apparent diabetic retinopathy; 38%, 17% and 4% had mild, moderate and severe non-proliferative diabetic retinopathy; and 13% had proliferative diabetic retinopathy. Of the 141 patients with diabetic retinopathy, 29% had bilateral CSME. Of the 132 diabetic patients (67 males and 65 females) returning for full eye exams, 52% were Hispanic, 21% African American, 14% Asian, and 8% NonHispanic Caucasian and Other, with an average age of 58.1 ± 9.4 years. Refractive errors were defined as spherical equivalent (SE) refraction, calculated as the spherical power plus one-half of the cylindrical power. Results: The overall mean spherical equivalent refraction M was −0.16 ± 1.50 D in the right eye (−6.0 D to +3.0 D) and +0.14 ± 1.35 D (−7.0 D to +4.0 D) in the left eye. Out of 132 patients, eight patients (6.1%) had visual acuity worse than 0.3 logMAR in both eyes. The right eyes of four patients and left eyes of eight patients had visual acuity worse than 0.3 logMAR, with fellow eyes having normal visual acuity. Conclusions: In a sample of largely minority, working age adults, there was very little refractive error and relatively good visual acuity when refracted, despite diabetic retinopathy or diabetic macular edema. Thus, working age diabetic patients may not regularly seek eye care for spectacle correction that would lead to the detection of diabetic retinopathy or diabetic macular edema.
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| 18. |
- Green, Jason J. A., et al.
(författare)
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Retina Artery to Vein Intensity Ratio as a Function of Wavelength and Dark-Field Offset With Low Cost Ophthalmoscope
- 2014
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Konferensbidrag (refereegranskat)abstract
- PurposeTo quantify light return from retinal vessels for oxygenation status. To use a low-cost Digital Light Ophthalmoscope (DLO) based on a novel structured light pattern Digital Light Projector for quantitative retinal imaging. MethodsFive normal subjects of ages 27-63 and various eye colors were imaged without mydriasis. The DLO produced a progressively scanning 6 pixel wide stripe, 96 stripe illumination pattern (85 μm stripe width at retina) with LEDs at 635 +/- 25nm (Red) and 535 +/- 70nm (Green) with a constant fixation target location across tests. The illumination was synchronized to a 13.2 Hz rolling shutter CMOS sensor (11 μm resolution at retina). To collect the light return from the retina at varying light multiply scattered levels, aperture offset was varied in position with respect to the illumination centerline: dark-field mode was obtained with large offsets and confocal mode had small offsets, where offset was varied from -517 μm (row start 30) to 1353 μm (row start 200). Multiple images of 12 bit dynamic range were captured in sequence, aligned with translational cross correlation, then time averaged to reduce noise. The artery and vein gray scale intensity level was measured at vessel centers for: 1) both vessels over background retina and 2) artery over the optic disc and vein over background. Mean-to-mean intensity ratios were then compared. ResultsWith an aperture width of 704 μm, intensity varied by 2.60 bits (a factor of 4.5) for each subject per condition: red, green, artery, and vein, 3.39 bits if same subject and condition (2.3% Red A/V ratio CoV σ/μ), and by 5.07 bits over all tests. Yet, the ratio (Red/Green Artery)/(Red/Green Vein) was close to unity across offsets and linear fits had an R^2 regression of, for case 1: 0.72, 0.06, 0.25, 0.18, and 0.49, and case 2: 0.0005, 0.89, 0.75, 0.50, and 0.18. The Artery/Vein ratio trend slopes, intercept points, and inversions varied between subjects, i.e. contrast reversals were observed. ConclusionsThe DLO can be utilized electronically to effectively perform quantitative fundus imaging at both Red and Green wavelengths, which is a step towards performing oximetry. 77 is zero offset
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| 19. |
- Hernandez-Moreno, Laura, et al.
(författare)
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Absent Foveal Pit, Also Known as Fovea Plana, in a Child without Associated Ocular or Systemic Findings
- 2018
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Ingår i: Case Reports in Ophthalmological Medicine. - : Hindawi Publishing Corporation. - 2090-6722 .- 2090-6730. ; , s. 1-5
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this report is to describe a case of bilateral foveal hypoplasia in the absence of other ophthalmological or systemic manifestations. We characterize the case of a 9-year-old Caucasian male who underwent full ophthalmologic examination, including functional measures of vision and structural measurements of the eye. Best corrected visual acuity was 0.50 logMAR in the right eye and 0.40 logMAR in the left eye. Ophthalmoscopy revealed a lack of foveal reflex that was further investigated. Optical coherence tomography (OCT) confirmed the absence of foveal depression (pit). OCT images demonstrated the abnormal structure of retina in a region in which we expected a fovea; these findings were decisive to determine the cause of reduced acuity in the child.
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| 20. |
- Ingling, Allen W, et al.
(författare)
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Fixation stability readily obtained from confocal color fundus imaging
- 2015
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 56:7, s. 515-515
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Tidskriftsartikel (refereegranskat)abstract
- PurposeStabile fixation underpins most visual tasks such as reading, and is important for accurate assessment of visual function and treatment. Retinal imaging instruments average images over time to improve the signal to noise ratio, discarding useful eye movement data. We determined whether the frame-to-frame motion of the retina during non-mydriatic color fundus imaging could provide fixation stability measures, e.g. Bivariate Contour Ellipse Area (BCEA). MethodsNon-mydriatic color fundus images were acquired using the Digital Light Ophthalmoscope (DLO). Twenty subjects with varied fundus pigmentation were tested without mydriasis. The DLO uses a digital light projector with LED light sources to provide the illumination for both confocal imaging and fixation stimuli. The DLO projects a series of lines across the fundus that is synchronized to the 2D CMOS sensor, providing high contrast confocal imaging. Monochromatic 40 deg images were acquired with alternating red and green LED illumination at 14.3 Hz and overlayed to present a pseudo-color image to the operator in real time. To reduce pupil constriction and patient discomfort, the green LED was long-pass filtered with a 570 nm filter. A 1.5mm entrance pupil and time-averaged power of <30 uW were used. Images were aligned automatically with custom software (MATLAB) using cross-correlation and 2D translation. A canvas of twice the image size was used to allow image alignment despite moderate eye movements. Blinks and large saccades were discarded and BCEA was computed. ResultsThe image alignment algorithm successfully aligned nearly all the frames, rejecting 3.7%, and allowing fixation stability to be computed from color fundus image data. The BCEA for 1 standard deviation was 2.97 log minarc2 for all subjects and both the red and yellow-orange illumination. There was no difference between the BCEA for red or yellow-orange illumination (t = .86). ConclusionsThe color DLO records sufficiently high quality images to reliably calculate measures of fixation stability. Despite recruiting an especially challenging population that included dark fundi, small pupils, high refractive errors, and media issues, we achieved success in all subjects tested to date.
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| 21. |
- Kathamuthu, GR, et al.
(författare)
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Strongyloidiasis stercoralis coinfection is associated with altered iron status biomarkers in tuberculous lymphadenitis
- 2022
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Ingår i: Frontiers in immunology. - : Frontiers Media SA. - 1664-3224. ; 13, s. 999614-
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Tidskriftsartikel (refereegranskat)abstract
- Soil-transmitted helminth [mainly Strongyloidiasis stercoralis (Ss)] and tuberculous lymphadenitis (TBL) coinfection in humans is a significant public health problem. We have previously shown that TBL+Ss+ coinfection significantly alters diverse cytokine, matrix metalloproteinase, and tissue inhibitors of metalloproteinase profiles. However, no data is available to understand the influence of Ss coinfection in TBL disease with respect to iron status biomarkers. Hence, we have studied the effect of Ss coinfection on the circulating levels of iron status (ferritin, transferrin [TF], apotransferrin [ApoT], hepcidin, hemopexin) biomarkers in TBL disease. Our results show that TBL+Ss+ and/or TBL+Ss- individuals are associated with significantly altered biochemical and hematological (red blood cell (RBC) counts, hemoglobin (Hb), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) were decreased, and platelets were increased) parameters compared to TBL-Ss+ individuals. Our results also show that TBL+Ss+ coinfection is associated with diminished circulating levels of ferritin, ApoT, hepcidin, and hemopexin compared to TBL+Ss- individuals. TBL+Ss+ and TBL+Ss- groups are associated with altered iron status biomarkers (decreased ferritin [TBL+Ss+ alone] and increased TF, ApoT, hepcidin and hemopexin [TBL+Ss- alone]) compared to TBL-Ss+ group. The heat map expression profile and principal component analysis (PCA) analysis of iron status biomarkers were significantly altered in TBL+Ss+ compared to TBL+Ss- and/or TBL-Ss+ individuals. A significant correlation (positive/negative) was obtained among the biochemical and hematological parameters (white blood cells (WBC)/ferritin, TF, and hepcidin, mean corpuscular hemoglobin concentration (MCHC)/ferritin and hemopexin) with iron status biomarkers. Finally, receiver operating characteristic (ROC) analysis revealed that hemopexin was significantly associated with greater specificity and sensitivity in discriminating TBL+Ss+ and TBL+Ss- coinfected individuals. Thus, our data conclude that Ss coinfection is associated with altered iron status biomarkers indicating that coinfection might alter the host-Mtb interface and could influence the disease pathogenesis.
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| 22. |
- Kathamuthu, GR, et al.
(författare)
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Systemic Levels of Pro-Inflammatory Cytokines and Post-Treatment Modulation in Tuberculous Lymphadenitis
- 2023
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Ingår i: Tropical medicine and infectious disease. - : MDPI AG. - 2414-6366. ; 8:3
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Tidskriftsartikel (refereegranskat)abstract
- Pro-inflammatory cytokines are potent stimulators of inflammation and immunity and markers of infection severity and bacteriological burden in pulmonary tuberculosis (PTB). Interferons could have both host-protective and detrimental effects on tuberculosis disease. However, their role has not been studied in tuberculous lymphadenitis (TBL). Thus, we evaluated the systemic pro-inflammatory (interleukin (IL)-12, IL-23, interferon (IFN)α, and IFNβ) cytokine levels in TBL, latent tuberculosis (LTBI), and healthy control (HC) individuals. In addition, we also measured the baseline (BL) and post-treatment (PT) systemic levels in TBL individuals. We demonstrate that TBL individuals are characterized by increased pro-inflammatory (IL-12, IL-23, IFNα, IFNβ) cytokines when compared to LTBI and HC individuals. We also show that after anti-tuberculosis treatment (ATT) completion, the systemic levels of pro-inflammatory cytokines were significantly modulated in TBL individuals. A receiver operating characteristic (ROC) analysis revealed IL-23, IFNα, and IFNβ significantly discriminated TBL disease from LTBI and/or HC individuals. Hence, our study demonstrates the altered systemic levels of pro-inflammatory cytokines and their reversal after ATT, suggesting that they are markers of disease pathogenesis/severity and altered immune regulation in TBL disease.
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| 23. |
- Langbol, M, et al.
(författare)
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Increased Antioxidant Capacity and Pro-Homeostatic Lipid Mediators in Ocular Hypertension-A Human Experimental Model
- 2020
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Ingår i: Journal of clinical medicine. - : MDPI AG. - 2077-0383. ; 9:9
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Tidskriftsartikel (refereegranskat)abstract
- The main risk factor for primary open-angle glaucoma (POAG) is increased intraocular pressure (IOP). It is of interest that about half of the patients have an IOP within the normal range (normal-tension glaucoma, NTG). Additionally, there is a group of patients with a high IOP but no glaucomatous neurodegeneration (ocular hypertension, OHT). Therefore, risk factors other than IOP are involved in the pathogenesis of glaucoma. Since the retina has a very high oxygen-demand, decreased autoregulation and a fluctuating oxygen supply to the retina have been linked to glaucomatous neurodegeneration. To assess the significance of these mechanisms, we have utilized a human experimental model, in which we stress participants with a fluctuating oxygen supply. Levels of oxidative stress molecules, antioxidants, and lipid mediators were measured in the plasma. Patients with NTG, OHT, and control subjects were found to have similar levels of oxidative stress markers. In contrast, patients with OHT had a higher level of total antioxidant capacity (TAC) and pro-homeostatic lipid mediators. Thus, we suggest that OHT patients manage fluctuating oxygen levels more efficiently and, thus, are less susceptible to glaucomatous neurodegenerations, due to enhanced systemic antioxidant protection.
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| 24. |
- Muller, Matthew S, et al.
(författare)
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Non-mydriatic color fundus imaging with the Digital Light Ophthalmoscope
- 2015
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Konferensbidrag (refereegranskat)abstract
- Purpose To provide non-mydriatic confocal color fundus imaging of sufficient quality for screening for diabetic retinopathy despite dark fundus pigmentation, small pupil, high refractive error, or other anterior segment issues. MethodsNon-mydriatic color fundus images of 34 volunteers (aged 39.2 ± 13.2 yr) were acquired using the Digital Light Ophthalmoscope (DLO). 10 subjects had dark fundi and/or high refractive errors, as well as other anterior segment issues. Unique to retinal cameras, the Digital Light Ophthalmoscope (DLO) uses a digital light projector with LED light sources to provide the illumination for both confocal imaging and fixation stimuli. The DLO projects a series of lines across the fundus that is synchronized to the electronic rolling shutter read-out on a 2D CMOS sensor, providing high contrast confocal imaging that is highly customizable through software. Monochromatic 40 deg field images were acquired with alternating red and green LED illumination at 14.3 Hz and overlayed to present a pseudo-color image to the operator in real time. To reduce pupil constriction and patient discomfort while maintaining strong blood absorption, the green illumination was long-pass filtered with a 570 nm filter, and a 1.5mm entrance pupil and time-averaged power of <30 uW was used. ResultsThe DLO provided gradable quality non-mydriatic fundus images in all tested subjects, including those with dark fundi or pupils < 2 mm, as judged by an EyePACS certified grader. The use of long pass filters in the green LED permitted high contrast, non-mydriatic images with illumination wavelengths >570 nm and limited pupil constriction. Retinal vessels at the 4th branch or smaller, as well as neovascularization in diabetic retinopathy, could be seen. Hyperpigmentation was clearly seen both peripherally as bear tracks and centrally at the posterior pole. The aperture width and color balance can be adjusted to provide high contrast and yet relatively uniform and natural color across the image. ConclusionsThe DLO provides confocal color fundus images in real time without the use of short (< 570nm) wavelength light. Despite recruiting an especially challenging population that included dark fundi, small pupils, high refractive errors, and media issues, we achieved a 100% success rate in obtaining gradable images for screening.
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| 25. |
- Muller, Matthew S., et al.
(författare)
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Non-mydriatic confocal retinal imaging using a digital light projector
- 2015
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Ingår i: <em>Proceedings of SPIE, vol</em> 9376. - : SPIE - International Society for Optical Engineering. ; , s. 93760E-1-93760E-10
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Konferensbidrag (refereegranskat)abstract
- A digital light projector is implemented as an integrated illumination source and scanning element in a confocal nonmydriatic retinal camera, the Digital Light Ophthalmoscope (DLO). To simulate scanning, a series of illumination lines are rapidly projected on the retina. The backscattered light is imaged onto a 2-dimensional rolling shutter CMOS sensor. By temporally and spatially overlapping the illumination lines with the rolling shutter, confocal imaging is achieved. This approach enables a low cost, flexible, and robust design with a small footprint. The 3rd generation DLO technical design is presented, using a DLP LightCrafter 4500 and USB3.0 CMOS sensor. Specific improvements over previous work include the use of yellow illumination, filtered from the broad green LED spectrum, to obtain strong blood absorption and high contrast images while reducing pupil constriction and patient discomfort.
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| 26. |
- Muller, Matthew S., et al.
(författare)
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Real-Time Retinal Imaging with Integrated Visual Function Testing Using the Digital Light Ophthalmoscope
- 2014
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Ingår i: IOVS. - Orlando, Florida, USA.
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Konferensbidrag (refereegranskat)abstract
- Abstract Purpose: To perform low cost fixation stability assessment and kinetic perimetry during live fundus viewing using the Digital Light Ophthalmoscope (DLO). Methods: Kinetic perimetry was performed on 12 undilated normal subjects aged 25 - 63 with real-time confocal retinal imaging using the DLO. Having similar functionality to a Scanning Laser Ophthalmoscope, but at far lower cost, the DLO uses a single digital light projector to provide both the illumination for confocal imaging, and the stimuli for visual function measurements. Confocal retinal imaging is performed at 20 Hz with a 35.1 deg field of view. The imaging illumination is provided by a red 630 nm LED, with 40 µW time-averaged power at the cornea. Stimuli are shown in black over the red imaging illumination and are operator controlled in shape and position in real-time. The black stimuli are easily seen by the subject and are also clearly visible on the live view of the fundus. Subjects were instructed to stare at a fixation target while a Goldman V size (1.72 deg diameter) target was presented near the optic nerve head. The path taken by the stimulus was guided by one of eight meridians that converged at a point on the optic nerve head. The meridians were equally separated by 45 deg, and 7 deg long. Each stimulus moved incrementally outwards, from “not seen” to “seen”, at approximately 2.5 deg per sec. Once the stimulus was seen by the subject, an 8 image frame buffer was saved. Fixation stability was separately measured by acquiring 60 frames over 3 sec while the subject fixated on a cross-hair target with 0.3 deg line thickness. Results: The stimuli were directly visible on the retinal image frames, providing precise visual function testing. The visual function maps, formed by registering and superimposing the fundus images obtained for each stimulus meridian path, agreed well with the boundaries of the optic nerve head. The subjects’ fixation was 0.25±0.13 deg, measured over a 2 sec blink-free interval of the 3 sec acquisition. Conclusions: The DLO with integrated visual function testing is a flexible and cost-effective platform for conducting image-corrected visual function tests, such as kinetic perimetry and fixation stability assessment, and can be readily extended to scotoma mapping and reading tests.
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| 27. |
- Ozawa, Glen Y., et al.
(författare)
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Central macular thickness of diabetic eyes with and without exudates within one disc diameter of the foveola
- 2014
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Konferensbidrag (refereegranskat)abstract
- Abstract Purpose: In diabetic retinopathy screenings, exudates within 1 disc diameter (DD) of the foveola are routinely used as a surrogate marker for clinically significant macular edema (CSME). We compared central macular thickness of diabetic eyes, which in photos, had and did not have exudates within 1 DD of the foveola. Methods: Patients were recruited from a diabetic retinopathy screening program serving mainly minorities in Alameda County, CA. One eye from each of 200 diabetic patients with diabetes was selected: 100 cases (50 males and 50 females) had exudates within 1 DD of the foveola, and 100 gender-, age-, and ethnicity-matched control diabetics did not have exudates within 1 DD of the foveola. Central macular thickness was determined using the iVue SD-OCT (Optovue Inc, Fremont, CA). Immediately following the OCT, three overlapping fundus photographs of each eye were taken with a Canon Cr-DGi nonmydriatic camera (Tokyo, Japan). Photos were graded by two EyePACS certified graders in a blind manner. Sensitivity and specificity of retinal photos for CSME were determined using the OCT as a gold standard. A 3-way ANOVA was performed for gender, age group (<55 years vs >55 years), and case versus control. Results: Central macular thickness was significantly greater for eyes with exudates within 1DD of the foveola versus eyes without (261±54 vs 244±23 μm, p=0.002). Notably, central macular thickness was greater in eyes with exudates within 1 DD of the fovea compared to those without in only the males (275±54 vs 249±25 μm, p=0.003). In the females, the two groups did not differ (247±51 vs 237±19 μm, p=0.2). ANOVA analysis also showed that central macular thickness was significantly greater among the entire group of males compared to the females (262±45 vs 243±39 μm, p<0.0001). Regardless of exudates, older patients (>55 years) had significantly greater central macular thickness than younger patients (260±54 vs 245±39 μm, p=0.009). In this study, exudates within 1 DD of the foveola had a sensitivity and specificity of 96% (95% CI=90-99%) and 82% (73-88%) for CSME, respectively. Conclusions: This study suggests that the surrogate marker for CSME, exudates within 1 DD of the foveola, is associated with central macular thickening. This central macular thickening is significantly greater in males, but not in females. Thus, the surrogate marker for CSME may be more important in males than in females.
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| 28. |
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| 29. |
- Porcelli, D., et al.
(författare)
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The importance of colloids and mires for the transport of uranium isotopes through the Kalix River watershed and Baltic Sea
- 1997
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Ingår i: Geochimica et Cosmochimica Acta. - 0016-7037 .- 1872-9533. ; 61:19, s. 4095-4113
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Tidskriftsartikel (refereegranskat)abstract
- The importance of colloids and organic deposits for the transport of uranium isotopes from continental source regions and through the estuarine environment was investigated in the mire-rich Kalix River drainage basin in northern Sweden and the Baltic Sea. Ultrafiltration techniques were used to separate uranium and other elements associated with colloids > 10 kD and >3 kD from "solute" uranium and provided consistent results and high recovery rates for uranium as well as for other elements from large volume samples. Uranium concentrations in 0.45 μm-filtered Kalix River water samples increased by a factor of 3 from near the headwaters in the Caledonides to the river mouth while major cation concentrations were relatively constant. 234U/238U ratios were high (δ234U = 770-1500) throughout the basin, without showing any simple pattern, and required a supply of 234U-rich water. Throughout the Kalix River, a large fraction (30-90%) of the uranium is carried by >10 kD colloids, which is compatible with uranium complexation with humic acids. No isotopic differences were found between colloid-associated and solute uranium. Within the Baltic Sea, about half of the uranium is removed at low salinities. The proportion that is lost is equivalent to that of river-derived colloid-bound uranium, suggesting that while solute uranium behaves conservatively during estuarine mixing, colloid-bound uranium is lost due to rapid flocculation of colloidal material. The association of uranium with colloids therefore may be an important parameter in determining uranium estuarine behavior. Mire peats in the Kalix River highly concentrate uranium and are potentially a significant source of recoil 234U to the mirewaters and river waters. However, mirewater data clearly demonstrate that only small 234U/238U shifts are generated relative to inflowing groundwater. A simple box model of uranium accumulation in peat and transport through the mire that is compatible with the mire data demonstrates that with efficient removal of uranium from solution, only small shifts in 234U/238U ratios can be generated in mirewater uranium. The measurements and model calculations show that mirewaters are not the primary source of the uranium in the river. Bedrock groundwaters with high 234U/238U ratios and uranium concentrations must be the dominant source of riverine uranium.
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| 30. |
- Schmidt, Linnéa, et al.
(författare)
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Case-specific potentiation of glioblastoma drugs by pterostilbene
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:45, s. 73200-73215
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Tidskriftsartikel (refereegranskat)abstract
- Glioblastoma multiforme (GBM, astrocytoma grade IV) is the most common malignant primary brain tumor in adults. Addressing the shortage of effective treatment options for this cancer, we explored repurposing of existing drugs into combinations with potent activity against GBM cells. We report that the phytoalexin pterostilbene is a potentiator of two drugs with previously reported anti-GBM activity, the EGFR inhibitor gefitinib and the antidepressant sertraline. Combinations of either of these two compounds with pterostilbene suppress cell growth, viability, sphere formation and inhibit migration in tumor GBM cell (GC) cultures. The potentiating effect of pterostilbene was observed to a varying degree across a panel of 41 patient-derived GCs, and correlated in a case specific manner with the presence of missense mutation of EGFR and PIK3CA and a focal deletion of the chromosomal region 1p32. We identify pterostilbene-induced cell cycle arrest, synergistic inhibition of MAPK activity and induction of Thioredoxin interacting protein (TXNIP) as possible mechanisms behind pterostilbene's effect. Our results highlight a nontoxic stilbenoid compound as a modulator of anticancer drug response, and indicate that pterostilbene might be used to modulate two anticancer compounds in well-defined sets of GBM patients.
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| 31. |
- Sivaramakrishnan, V. C., et al.
(författare)
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Influence of convergence on vertical fusional vergence amplitude
- 2005
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Ingår i: American Journal of Ophthalmology. - 0002-9394 .- 1879-1891. ; 139:3 Suppl., s. S46-
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Deficiency in vertical fusional vergence amplitude (VFVA) is known to cause asthenopia and oculomotor imbalances. The measurement of VFVA however is confounded by its increase with convergence (Hara et al., 1998). A quantitative relationship between the two vergences is thus necessary to predict the VFVA at a given convergence angle. Here, we sought to derive such a relationship by measuring the VFVA at a range of convergence angles. Methods: 30 subjects (17–21 yrs) wearing red-green goggles fused a pair of red-green concentric circles projected on a computer monitor at a distance of 50 cms in a dark room. The horizontal and vertical separation between the red-green circles determined the convergence and vertical vergence demand respectively. The VFVA was measured at 8 equally spaced convergence demands ranging from 0.58° to 11.13°. The convergence demands were either systematically increased or randomly varied across different sessions. in each session, the convergence demand was kept constant while the vertical vergence demand was varied in steps of 0.03°. The maximum vertical vergence demand that could be fused determined the VFVA. Results: The subjects’ data was divided into four groups based on the range of convergence demands that could be fused. in all the groups, the VFVA increased linearly with the systematic increase in convergence demand (mean regression equation: y 0.15x 0.49). Randomizing the convergence demands did not show any significant change in this relationship (y0.12x 0.80). Conclusion: The VFVA increases linearly in the range of convergence demands tested. The linear regression equation derived could be used in a clinical setup to predict the VFVA at a given convergence angle
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| 32. |
- Young, Stuart B., et al.
(författare)
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Central Macular Thickness in Diabetic Patients : A Gender Based Analysis
- 2014
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Konferensbidrag (refereegranskat)abstract
- PURPOSE: To investigate gender differences in central macular thickness (CMT) in underserved diabetic patients who were judged to have clinically significant macular edema (CSME), using the criterion of hard exudates within 1500 microns of the fovea. METHODS: Using EyePACS certified graders, 142 of 2080 diabetic patients from Alameda County, CA, clinics, had CSME as judged from color fundus images (Canon CR6-45NM). Of the 2080 patients, 1784 were imaged with SD-OCT (iVUE). Graders then analyzed the SD-OCT images for hard exudates and macular edema, excluding subjects with poor fixation or other ocular conditions. From these data, 142 patients with CSME, 11 males had CMT >300 microns. The 11 females from the group with the greatest values of CMT were then compared for CMT, and mean age. A control group, diabetic patients without CSME, showed a 12-micron larger CMT for males, as compared with females. Thus, a one-tailed t-test was used to determine if the CMT for males with CSME also was greater than for females by 12 microns. We compared mean age, self-report of duration of diabetes, and HbA1c values between genders. RESULTS: Males with CSME had an average CMT of 377 microns, statistically greater than the 12 micron difference expected between genders, with females averaging 321 microns (p<0.05). There was no statistical significance in the mean age between genders 59.3 vs. 59.2 yr. (p>0.05) or the population HbA1c levels 9.5 vs. 9.3% for males and females (p>0.05), respectively. While females had slightly longer durations of diabetes, Chi square analysis also showed no significance between genders (p>0.05). In the OCT images, males had cysts that were larger and more numerous. CONCLUSIONS: In patients with CSME, males had greater CMT than females. This difference is not explained by differences in thickness with gender when CSME is not found, nor by age or duration of diabetes. Instead, the cystic changes in the retinas of males were more striking.
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