High prevalence of PRPH2 in autosomal dominant retinitis pigmentosa in france and characterization of biochemical and clinical features.

PURPOSE: To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report 6 novel mutations, to characterize the biochemical features of a recurrent novel mutation, and to study the clinical features of adRP patients. DESIGN: Retrospective clinical and molecular genetic study. METHODS: Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging, and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot. RESULTS: We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1-0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families. CONCLUSIONS: The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0%-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases, which could be underdiagnosed.

CONVERSION TO AFLIBERCEPT THERAPY VERSUS CONTINUING WITH RANIBIZUMAB THERAPY FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION DEPENDENT ON MONTHLY RANIBIZUMAB TREATMENT.

PURPOSE: To compare the effects of converting to aflibercept therapy with continuing ranibizumab therapy in eyes with neovascular age-related macular degeneration requiring monthly ranibizumab treatment. METHODS: Patients were selected from the 104 patients (115 eyes) already enrolled in an "Observe and Plan" prospective case series that included treating neovascular age-related macular degeneration with ranibizumab for 24 months. Patients who still needed monthly retreatment at the end of a 2-year study were randomized to either continue ranibizumab therapy or to convert to aflibercept therapy. Outcome measures included average interval between treatments, resolution of exudative signs, number of retreatments, and change in visual acuity over 12 months (the third treatment year). RESULTS: Nineteen patients (21 eyes) met the inclusion criteria. Ten eyes were randomized to receive aflibercept, and 11 eyes remained on ranibizumab. Groups were balanced for baseline characteristics. Outcomes were similar in the 2 groups over a 12-month study duration, with no statistical difference. CONCLUSION: This comparative pilot study suggests that neovascular age-related macular degeneration requiring monthly retreatment with ranibizumab may respond in similar ways to both ranibizumab and aflibercept treatment. Larger sample sizes would be needed to confirm this observation.

Espectroscopia de fotoelétrons de limiares de átomos e moléculas

A threshold photoelectron spectrometer applied to the study of atomic and molecular threshold photoionization processes is described. The spectrometer has been used in conjunction with a toroidal grating monochromator at the National Synchrotron Radiation Laboratory (LNLS), Brazil. It can be tuned to accept threshold electrons (< 20 meV) and work with a power resolution of 716 (~18 meV at 12 eV) with a high signal/noise ratio. The performance of this apparatus and some characteristics of the TGM (Toroidal Grating Monochromator) beam line of LNLS are described and discussed by means of argon, O2 and N2 threshold photoelectron spectra.

Elucidando os estados de oxidação do nitrogênio através da espectroscopia de absorção de raios-X na borda K do nitrogênio

The potentialities of X-ray Absorption Near Edge Spectroscopy (XANES) of the N K edge (N K) obtained with the spherical grating monochromator beam line at the Brazilian National Synchrotron Light Laboratory are explored in the investigation of poly(aniline), nanocomposites and dyes. Through the analysis of N K XANES spectra of conducting polymers and many other dye compounds that are dominated by 1s®p* transitions, it was possible to correlate the band energy value with the nitrogen oxidation states. An extensive N K XANES spectral database was obtained, thus permitting the elucidation of the nature of different nitrogens present in the intercalated conducting polymers.

Visual impairment and multimorbidity in a representative sample of the Spanish population

BACKGROUND: In the context of population aging, visual impairment has emerged as a growing concern in public health. However, there is a need for further research into the relationship between visual impairment and chronic medical conditions in the elderly. The aim of our study was to examine the relationship between visual impairment and three main types of co-morbidity: chronic physical conditions (both at an independent and additive level), mental health and cognitive functioning. METHODS: Data were collected from the COURAGE in Europe project, a cross-sectional study. A total of 4,583 participants from Spain were included. Diagnosis of chronic medical conditions included self-reported medical diagnosis and symptomatic algorithms. Depression and anxiety were assessed using CIDI algorithms. Visual assessment included objective distance/near visual acuity and subjective visual performance. Descriptive analyses included the whole sample (n = 4,583). Statistical analyses included participants aged over 50 years (n = 3,625; mean age = 66.45 years) since they have a significant prevalence of chronic conditions and visual impairment. Crude and adjusted binary logistic regressions were performed to identify independent associations between visual impairment and chronic medical conditions, physical multimorbidity and mental conditions. Covariates included age, gender, marital status, education level, employment status and urbanicity. RESULTS: The number of chronic physical conditions was found to be associated with poorer results in both distance and near visual acuity [OR 1.75 (CI 1.38-2.23); OR 1.69 (CI 1.27-2.24)]. At an independent level, arthritis, stroke and diabetes were associated with poorer distance visual acuity results after adjusting for covariates [OR 1.79 (CI 1.46-2.21); OR 1.59 (CI 1.05-2.42); OR 1.27 (1.01-1.60)]. Only stroke was associated with near visual impairment [OR 3.01 (CI 1.86-4.87)]. With regard to mental health, poor subjective visual acuity was associated with depression [OR 1.61 (CI 1.14-2.27); OR 1.48 (CI 1.03-2.13)]. Both objective and subjective poor distance and near visual acuity were associated with worse cognitive functioning. CONCLUSIONS: Arthritis, stroke and the co-occurrence of various chronic physical diseases are associated with higher prevalence of visual impairment. Visual impairment is associated with higher prevalence of depression and poorer cognitive function results. There is a need to implement patient-centered care involving special visual assessment in these cases.

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

Objectives: To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design: Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection: Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes: The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results: The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. Conclusions: This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis.

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

Objectives: To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design: Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection: Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes: The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results: The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. Conclusions: This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis.

CFH Y402H polymorphism and response to intravitreal Ranibizumab in brazilian patients with neovascular age-related macular degeneration

Objective: To investigate the association between CFH gene polymorphism and response to ranibizumab in Brazilian patients with neovascular age-related macular degeneration (AMD).Methods: 95 patients were genotyped for the CFH rs1061170 (Y402H) single nucleotide polymorphism. Patients with neovascular AMD initially received intravitreal ranibizumab injections for three months and were retreated as needed. Visual acuity (VA) and central retinal thickness (CRT) were measured before treatment and at 1, 3, 6, and 12 months post-treatment.Results: For patients with the TT and TC genotypes, paired comparisons of VA showed a statistically significant improvement when the data obtained at all visits were compared with baseline. Patients homozygous for the risk genotype (CC) did not show a statistically significant improvement when VA obtained at visits 1, 3, 6 and 12 were compared with baseline. For all genotypes, paired comparisons of CRT showed a statistically significant improvement when the data obtained at visits 1, 3, 6 and 12 were compared with baseline.Conclusion: Patients with the CC genotype showed poorer long-term functional response to intravitreal ranibizumab.

Serva ad ministrare : tjänandets ethos i vårdledarskap

Avhandlingen syftar till att ur ett vårdvetenskapligt perspektiv beskriva och upptäcka tjänandets meningsinnehåll samt fördjupa förståelsekunskap om tjänandets ethos i förhållande till vårdledarskap med en inriktning på det vårdadministrativa. Syftet är även att skapa en idealmodell som öppnar för en ny eller annorlunda förståelsehorisont för tjänandets ethos i vårdledarskap. Kunskapssökandet sker genom följande delstudier: (1) I begreppsbestämningen genomförs begreppsanalyser av tjäna och tjänst med avsikt att öppna för en grundförståelse och tankestruktur i forskningsuppgiften. (2) I det idéhistoriska spåras tjänandets ontologiska arv och idémönster fram genom tolkning av historiska källornas texter från 1900-talets första hälft i ljuset av sjuksköterskeledarskap utgående från Sophie Mannerheims, Bertha Wellins och Bergljot Larssons idéer och tankeströmningar. (3) Sökandet fortsätter i dagens kliniska kontextbas genom kvalitativa djupintervjuer med 30 deltagare (vårdledare och vårdare) från Finland, Sverige och Norge. Förförståelsen och forskningens teoretiska perspektiv har rötter i Erikssons caring science-tradition och vårdvetenskapens ontologiska grundantaganden som utvecklats vid Åbo Akademi, Enheten för vårdvetenskap i Vasa. Forskningsansatsen är inspirerad av H-G Gadamers filosofiska hermeneutik. Designen är explorativ-deskriptiv, idiografisk och implicerar ett hypotetisk-deduktivt tillvägagångssätt. Tjänandet och vårdledarskapets ethos upptäcks och tolkas genom det metodologiska närmandet: Erikssons hermeneutiska begreppsbestämningsmodell, idéhistoriska läsakt och hermeneutiska läsakt. Materialet bildar förståelsehorisonter genom den hermeneutiska dialogens successiva och oändliga rörelse. Horisonterna reflekteras mot teorikärnan för att öppna för ny förståelse av tjänandets meningsinnehåll, vårdledarskap och vårdadministration. I slutandet sker en horisontsammansmältning och en reflektiv anslutning till vårdvetenskapens teorikärna som visar hur tjänandets ethos blir evident i vårdledarskap. Resultatet visar att vårdledarskap som är tjänande för patienten och vårdkulturen synliggörs i vårdadministrationens kontext genom huvudets skärpa, handens gärningar och hjärtats visdom. Tjänandets sanna, goda och sköna tidlösa rörelse är riktad mot hälsa och helande. I dag sammankopplas tjänande inom vårdorganisationer med hälsoekonomiska förhållanden, effektivitet, produktivitet och rationalitet, vilket strider mot tjänandets värdegrund, människans värdighet och respekt för livet. Vårdorganisationernas etiska ansvar är att fungera som samhälleliga förebilder, tillrättalägga för vårdadministrationernas tjänande och stå i patientens tjänst. Gestaltningen av tjänandets ethos i vårdledarskap öppnar för nya diskurser, riktningar, visioner och handlingar i den vårdadministrativa verkligheten. Avhandlingen ger vårdvetenskapens systematiska grundforskning ett teoritillskott av fördjupad förståelse av tjänandets och vårdledarskapets historiska och samtida ontologiska evidens och ethos med applikationen på klinisk vårdvetenskap.

Contrast sensitivity threshold measured by sweep-visual evoked potential in term and preterm infants at 3 and 10 months of age

Although healthy preterm infants frequently seem to be more attentive to visual stimuli and to fix on them longer than full-term infants, no difference in visual acuity has been reported compared to term infants. We evaluated the contrast sensitivity (CS) function of term (N = 5) and healthy preterm (N = 11) infants at 3 and 10 months of life using sweep-visual evoked potentials. Two spatial frequencies were studied: low (0.2 cycles per degrees, cpd) and medium (4.0 cpd). The mean contrast sensitivity (expressed in percentage of contrast) of the preterm infants at 3 months was 55.4 for the low spatial frequency (0.2 cpd) and 43.4 for the medium spatial frequency (4.0 cpd). At 10 months the low spatial CS was 52.7 and the medium spatial CS was 9.9. The results for the term infants at 3 months were 55.1 for the low spatial frequency and 34.5 for the medium spatial frequency. At 10 months the equivalent values were 54.3 and 14.4, respectively. No difference was found using the Mann-Whitney rank sum T-test between term and preterm infants for the low frequency at 3 or 10 months or for the medium spatial frequency at 3 or 10 months. The development of CS for the medium spatial frequency was equally fast for term and preterm infants. As also observed for visual acuity, CS was equivalent among term and preterm infants, suggesting that visual experience does not modify the development of the primary visual pathway. An earlier development of synapses in higher cortical visual areas of preterm infants could explain the better use of visual information observed behaviorally in these infants.

Radial frequency stimuli and sine-wave gratings seem to be processed by distinct contrast brain mechanisms

An assumption commonly made in the study of visual perception is that the lower the contrast threshold for a given stimulus, the more sensitive and selective will be the mechanism that processes it. On the basis of this consideration, we investigated contrast thresholds for two classes of stimuli: sine-wave gratings and radial frequency stimuli (i.e., j0 targets or stimuli modulated by spherical Bessel functions). Employing a suprathreshold summation method, we measured the selectivity of spatial and radial frequency filters using either sine-wave gratings or j0 target contrast profiles at either 1 or 4 cycles per degree of visual angle (cpd), as the test frequencies. Thus, in a forced-choice trial, observers chose between a background spatial (or radial) frequency alone and the given background stimulus plus the test frequency (1 or 4 cpd sine-wave grating or radial frequency). Contrary to our expectations, the results showed elevated thresholds (i.e., inhibition) for sine-wave gratings and decreased thresholds (i.e., summation) for radial frequencies when background and test frequencies were identical. This was true for both 1- and 4-cpd test frequencies. This finding suggests that sine-wave gratings and radial frequency stimuli are processed by different quasi-linear systems, one working at low luminance and contrast level (sine-wave gratings) and the other at high luminance and contrast levels (radial frequency stimuli). We think that this interpretation is consistent with distinct foveal only and foveal-parafoveal mechanisms involving striate and/or other higher visual areas (i.e., V2 and V4).

Mesopic radial frequency contrast sensitivity function for young and older adults

The objective of the present study was to determine contrast sensitivity curves of concentric circular patterns with radial frequencies of 0.25, 0.5, 1.0, 2.0, and 4.0 cycles per degree in young and older adult volunteers. These parameters were also compared with sensitivity contrasts for sine-wave gratings. All participants had normal acuity vision and were free of identifiable ocular illness. Contrast sensitivity was measured in 6 young adults aged 19 to 23 years and 6 older adults aged 60 to 69 years using the psychophysical forced-choice method. In this paradigm the volunteers had to decide which of two stimuli contained the above radial frequencies at low contrast levels. The other neutral stimulus was gray with homogeneous luminance. We detected a decline in contrast sensitivity for older adults at all radial frequencies compared to young adults. Also, contrast sensitivity for sine-wave gratings at all measured frequencies was better, as predicted, for all young adults. Maximum sensitivities in the radial frequency contrast sensitivity function and contrast sensitivity function occurred at 0.25 and 0.5 cycles per degree, respectively, for both young and older adults. These results suggest age-related changes in the contrast sensitivity function for concentric symmetrical stimuli.

Differential effects of aging on spatial contrast sensitivity to linear and polar sine-wave gratings

Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.

Acute effect of alcohol intake on sine-wave Cartesian and polar contrast sensitivity functions

The aim of this study was to assess contrast sensitivity for angular frequency stimuli as well as for sine-wave gratings in adults under the effect of acute ingestion of alcohol. We measured the contrast sensitivity function (CSF) for gratings of 0.25, 1.25, 2.5, 4, 10, and 20 cycles per degree of visual angle (cpd) as well as for angular frequency stimuli of 1, 2, 4, 24, 48, and 96 cycles/360°. Twenty adults free of ocular diseases, with normal or corrected-to-normal visual acuity, and no history of alcoholism were enrolled in two experimental groups: 1) no alcohol intake (control group) and 2) alcohol ingestion (experimental group). The average concentration of alcohol in the experimental group was set to about 0.08%. We used a paradigm involving a forced-choice method. Maximum sensitivity to contrast for sine-wave gratings in the two groups occurred at 4 cpd sine-wave gratings and at 24 and 48 cycles/360° for angular frequency stimuli. Significant changes in contrast sensitivity were observed after alcohol intake compared with the control condition at spatial frequency of 4 cpd and 1, 24, and 48 cycles/360° for angular frequency stimuli. Alcohol intake seems to affect the processing of sine-wave gratings at maximum sensitivity and at the low and high frequency ends for angular frequency stimuli, both under photopic luminance conditions.

Kr-Ar laser Raman spectrometer for low temperature measurements /

A Czerny Mount double monochromator is used to measure Raman scattered radiation near 90" from a crystalline, Silicon sample. Incident light is provided by a mixed gas Kr-Ar laser, operating at 5145 A. The double monochromator is calibrated to true wavelength by comparison of Kr and Ar emission Une positions (A) to grating position (A) display [1]. The relationship was found to be hnear and can be described by, y = 1.219873a; - 1209.32, (1) where y is true wavelength (A) and xis grating position display (A). The Raman emission spectra are collected via C"*""*" encoded software, which displays a mV signal from a Photodetector and allows stepping control of the gratings via an A/D interface. [2] The software collection parameters, detector temperature and optics are optimised to yield the best quality spectra. The inclusion of a cryostat allows for temperatmre dependent capabihty ranging from 4 K to w 350 K. Silicon Stokes temperatm-e dependent Raman spectra, generally show agreement with Uterature results [3] in their frequency haxdening, FWHM reduction and intensity increase as temperature is reduced. Tests reveal that a re-alignment of the double monochromator is necessary before spectral resolution can approach literature standard. This has not yet been carried out due to time constraints.