RPE Changes Research Articles

High-Intensity Interval Training in Middle-Distance NCAA Division I 800/1500m Collegiate Athletes

Background: High-intensity interval training (HIIT) has grown in popularity, with studies demonstrating improvements in aerobic and anaerobic performances within Sedentary and Recreationally active adults. Little research has been comprised on collegiate, middle-distance runners (800m/1500m). Objective: This research study aimed to investigate the impact of four-weeks HIIT cycling training on collegiate 800/1500m runners performance, and determine whether HIIT can be used as an alternative training method for student athletes. Methods: Twelve middle-distance runners were recruited, with six athletes completing the intervention. Athletes completed pre-testing, which included a 1500m time trial, a GXT, stride length and frequency measurements, and MVIC, using Biopac electromyography (EMG). After pre-testing, athletes completed four weeks of HIIT twice per week. The HIIT consisted of four 20-second bouts with 4 minutes recovery. Following the completion of the training intervention, post-testing was performed for all measures. A paired t-test was used to determine differences between pre- and post-performance tests. An ANOVA was used to determine changes in heart rate and RPE during the GXT. Results: Significant changes were demonstrated between the pre- and post-muscle activation tests of the quadriceps (p=0.05). Significant changes were seen with both HR (p<0.05) and RPE (p<0.05) throughout the GXT. No other significant differences were demonstrated between pre- and post-performance tests, concluding four-weeks HIIT does not alter 800/1500m performance. Conclusion: From the results of this study, HIIT could be used as an alternate method for training for 800/1500m runners. Further reasearch should be conducted toto further understand the impacts of HIIT on middle distance athletes.

Polypoidal Choroidal Vasculopathy: Outer Retinal and Choroidal Changes and Neovascularization Development in the Fellow Eye.

We investigated the outer retinal, RPE, and choroidal changes and the development of choroidal neovascularization (CNV) in fellow eyes of patients with unilateral polypoidal choroidal vasculopathy or aneurysmal type 1 neovascularization (PCV/AT1). In this retrospective observational cohort study, 263 patients with unilateral PCV/AT1 were enrolled. Fundus photography, enhanced depth imaging optical coherence tomography, and indocyanine green angiography at baseline and follow-up were analyzed. Incidence and risk factors for the development of CNV were analyzed. In fellow eyes of unilateral PCV/AT1 cases, RPE and outer retinal abnormalities were observed in 222 (84%) eyes, and dilated Haller vessels (pachyvessel) were identified in the corresponding abnormality area in 157 (71%) eyes. Follow-up data were available for 233 patients. During a 27.6-month mean follow-up period, 20/233 (9%) eyes had CNV (12 PCV/AT1 and eight type 1 CNV). In 18 eyes (90%), CNV developed at the RPE or outer retinal abnormality areas accompanied by pachyvessel. A significantly higher risk for CNV was observed if RPE and outer retinal abnormalities were accompanied by pachyvessel (hazard ratio, 9.3; 95% confidence interval, 1.1-75.9, P = 0.037). RPE and outer retinal abnormalities were common in fellow eyes of patients presenting with unilateral PCV/AT1. CNV developed in fellow eyes of 9% of patients, frequently in the areas with RPE and outer retinal abnormality accompanied by pachyvessel.

BETA ZONE OF PERIPAPILLARY ATROPHY BY OPTICAL COHERENCE TOMOGRAPHY AS A BIOMARKER OF GLAUCOMA ASSOCIATED WITH MYOPIA

Purpose of the study was to assess changes in the peripapillary retina and in patients with glaucoma associated with myopia and uncomplicated myopia by spectral domain optical coherence tomography. Material and methods. We examined 26 patients (26 eyes) with a clinically advanced of primary open-angle glaucoma on eyes with high myopia and 30 people (30 eyes) with uncomplicated myopia. Spectral domain optical coherence tomography was included in the examination. Results and discussion. A reduction in the rim area in patients with glaucoma combined with myopia, compared with patients with uncomplicated myopia ( M ± SD , respectively, 1.03 ± 0.36 and 1.60 ± 0.42 mm2, p < 0.05) develops against the background of thinning of the choroid, mainly in the lower one (131.36 ± 41.98 and 226,5 ± 98.13 mm, respectively; р = 0.01) and nasal (57.63 ± 9.81 and 216 ± 122.4 mm, respectively; р = 0.0006) segments and is accompanied by an increase in the area of the peripapillary atrophy (1.94 ± 0,5 and 1.05 ± 0.15 mm, respectively; р = 0.005), which indicates the inconsistency of trophic and metabolic processes. In patients with myopia in peripapillary atrophy zone, a gamma zone was identified, in which sclera and RNFL were visualized. The Bruch’s border membrane, retinal pigment epithelium, photoreceptors, and choroid coincided. In myopia combined with glaucoma, along with the gamma zone, the beta zone was visualized, which is characterized by degenerative changes in RPE and photoreceptors against the background of choriocapillary obliteration. Conclusion. Choroidal changes and the presence of beta zone are differential diagnostic criteria for glaucoma associated with myopia and can be used for diagnosis of glaucoma in combination with myopia.

Predictors of change in affect in response to high intensity interval exercise (HIIE) and sprint interval exercise (SIE)

Affect is typically positive at intensities below the lactate or ventilatory threshold, yet more aversive responses occur at supra-threshold intensities which may reduce positive perceptions of exercise. Completion of high intensity interval exercise (HIIE) typically elicits a reduction in affect, yet greater post-exercise enjoyment has been reported in response to HIIE versus moderate intensity continuous exercise (MICE). This study examined affectual responses to HIIE and sprint interval exercise (SIE) in 71 active men and women (age = 24.0 ± 4.8 year). Participants performed various HIIE and SIE regimes on the cycle ergometer during which affect (+5 – −5 scale), rating of perceived exertion (RPE, Borg 1–10 scale), and blood lactate concentration (BLa) were determined. Enjoyment was measured post-exercise using the PACES scale. Predictors of change in these variables in response to exercise were identified using multiple regression. Results showed a significant reduction in affect (p = .001) which was greater (p = .03) with SIE (−5.7 ± 2.7) compared to HIIE (−4.3 ± 2.4). Nevertheless, there was marked variability in the affect response across participants, as its change ranged from −1 to −7 units from pre- to post-exercise in 85% of all sessions. Sixty two percent of the change in affect seen across regimes was explained by baseline affect, BLa, and enjoyment. Significant associations were shown between the change in affect and baseline affect (r = −0.46, p < .001) and change in RPE (r = −0.59, p < .001). In addition, RPE significantly increased in response to HIIE (6.1 ± 1.7) and SIE (6.9 ± 2.0) but was not different (p = .050) between regimes. Our findings document an intensity-dependent relationship between affect and intensity during interval training, as supramaximal intensities elicit a larger decline in affect compared to submaximal intensities. In addition, pre-exercise affect is associated with the magnitude of change in affect reported in response to interval exercise.

Absence of DJ-1 causes age-related retinal abnormalities in association with increased oxidative stress

Oxidative stress alters physiological function in most biological tissues and can lead to cell death. In the retina, oxidative stress initiates a cascade of events leading to focal loss of RPE and photoreceptors, which is thought to be a major contributing factor to geographic atrophy. Despite these implications, the molecular regulation of RPE oxidative stress under normal and pathological conditions remains largely unknown. A better understanding of the mechanisms involved in regulating RPE and photoreceptors oxidative stress response is greatly needed. To this end we evaluated photoreceptor and RPE changes in mice deficient in DJ-1, a protein that is thought to be important in protecting cells from oxidative stress.Young (3 months) and aged (18 months) DJ-1 knockout (DJ-1 KO) and age-matched wild-type mice were examined. In both group of aged mice, scanning laser ophthalmoscopy (SLO) showed the presence of a few autofluorescent foci. The 18 month-old DJ-1 KO retinas were also characterized by a noticeable increase in RPE fluorescence to wild-type. Optical coherence tomography (OCT) imaging demonstrated that all retinal layers were present in the eyes of both DJ-1 KO groups. ERG comparisons showed that older DJ-1 KO mice had reduced sensitivity under dark- and light-adapted conditions compared to age-matched control. Histologically, the RPE contained prominent vacuoles in young DJ-1 KO group with the appearance of enlarged irregularly shaped RPE cells in the older group. These were also evident in OCT and in whole mount RPE/choroid preparations labeled with phalloidin. Photoreceptors in the older DJ-1 KO mice displayed decreased immunoreactivity to rhodopsin and localized reduction in cone markers compared to the wild-type control group. Lower levels of activated Nrf2 were evident in retina/RPE lysates in both young and old DJ-1 KO mouse groups compared to wild-type control levels. Conversely, higher levels of protein carbonyl derivatives and iNOS immunoreactivity were detected in retina/RPE lysates from both young and old DJ-1 KO mice.These results demonstrate that DJ-1 KO mice display progressive signs of retinal/RPE degeneration in association with higher levels of oxidative stress markers. Collectively this analysis indicates that DJ-1 plays an important role in protecting photoreceptors and RPE from oxidative damage during aging.

Acute Effects of Resistance Exercise With Continuous and Intermittent Blood Flow Restriction on Hemodynamic Measurements and Perceived Exertion.

This study compared the acute effects of low-intensity resistance exercise (RE) sessions for the upper limb with continuous and intermittent blood flow restriction (BFR) and high-intensity RE with no BFR on lactate, heart rate, double product (DP; heart rate times systolic blood pressure), and perceived exertion (RPE). Ten recreationally trained men (1-5 years strength training; age mean = 19 ± 0.82 years) performed three experimental protocols in random order: (a) low-intensity RE at 20% one-repetition maximum (1RM) with intermittent BFR (LI + IBFR), (b) low-intensity RE at 20% 1RM with continuous BFR (LI + CBFR), and (c) high-intensity RE at 80% 1RM. The three RE protocols increased lactate and DP at the end of the session ( p < .05) and increased heart rate at the end of each exercise ( p < .05). However, greater local and general RPE was observed in the high-intensity protocol compared with LI + IBFR and LI + CBFR in the lat pull-down, triceps curl, and biceps curl exercises ( p < .05). A greater percentage change in DP and lactate was observed for continuous BFR compared with intermittent BFR; however, RPE was lower for intermittent BFR. In conclusion, intermittent BFR appears to be an excellent option for physical training because it did not differ significantly from continuous BFR in any variable and promoted a lower percentage change in DP and RPE.

Reliability of Perceived Discomfort when Walking with Different Blood Flow Restriction Pressures in Young Adults

Previous studies using blood flow restriction (BFR) with low intensity aerobic exercise report increases in muscle hypertrophy, strength, and aerobic capacity without muscle damage; however, BFR exercise can be uncomfortable. PURPOSE: To assess the reliability of perceived discomfort when walking with BFR at different restrictive pressures. METHODS: Seventeen men and 15 women (aged 24.09 ± 4.14 yr) visited the laboratory 8 times. On the first and 2nd visit, subjects completed paperwork, screening and completed a familiarization session which included pre and post MVC of the right quadriceps and walking on a treadmill for 10 min at 3.5 mph and at 50% of total occlusion pressure. During the 3rd – 8th visits, each separated by 24 hrs, subjects performed pre MVC and immediate post MVC following 20 min of treadmill walking using BFR cuffs at a randomized pressure of 40%, 50%, or 60% total occlusion pressure. RPE and perceived discomfort were assessed at the end of treadmill walking. RESULTS: There were no significant day (1 vs 2), time (pre vs post) and condition (40%, 50%, 60%) effects or interactions for MVC (repeated measures ANOVA) and RPE (Wilcoxon Signed Ranks Test). Although no differences in discomfort were found for 40% and 50% (p ≥ 0.05), discomfort at 60% was significant (p= 0.021) between visits with day 2 significantly less than day 1 (2.5±1.9 vs 3.3±2.1, respectively). Additionally, intraclass correlation coefficients between days were only moderate and ranged from 0.64 -0.79 for RPE and from 0.69-0.85 for discomfort across occlusion pressures. CONCLUSION: 20 min walking exercise with BFR at 40%, 50%, or 60% elicited no changes in MVC and RPE, however, only discomfort at the highest pressure was different between days, suggesting that subjects could not distinguish differences in occlusion pressure between 40% and 60% of total occlusion.

A Targeted Inhibitor of the Alternative Complement Pathway Accelerates Recovery From Smoke-Induced Ocular Injury.

PurposeMorphologic and genetic evidence exists that an overactive complement system driven by the complement alternative pathway (AP) is involved in pathogenesis of age-related macular degeneration (AMD). Smoking is the only modifiable risk factor for AMD. As we have shown that smoke-related ocular pathology can be prevented in mice that lack an essential activator of AP, we ask here whether this pathology can be reversed by increasing inhibition in AP.MethodsMice were exposed to either cigarette smoke (CS) or filtered air (6 hours/day, 5 days/week, 6 months). Smoke-exposed animals were then treated with the AP inhibitor (CR2-fH) or vehicle control (PBS) for the following 3 months. Spatial frequency and contrast sensitivity were assessed by optokinetic response paradigms at 6 and 9 months; additional readouts included assessment of retinal morphology by electron microscopy (EM) and gene expression analysis by quantitative RT-PCR.ResultsThe CS mice treated with CR2-fH showed significant improvement in contrast threshold compared to PBS-treated mice, whereas spatial frequency was unaffected by CS or pharmacologic intervention. Treatment with CR2-fH in CS animals reversed thinning of the retina observed in PBS-treated mice as analyzed by spectral-domain optical coherence tomography, and reversed most morphologic changes in RPE and Bruch's membrane seen in CS animals by EM.ConclusionsTaken together, these findings suggest that AP inhibitors not only prevent, but have the potential to accelerate the clearance of complement-mediated ocular injury. Improving our understanding of the regulation of the AP is paramount to developing novel treatment approaches for AMD.

The within-participant correlation between perception of effort and heart rate-based estimations of training load in elite soccer players

ABSTRACTThe measurement of relative physiological stress during training is important because this is the stimulus for the long-term adaptive response. Measurements of perceived exertion (RPE) have been reported to correlate with the heart rate during field-based training sessions. Nevertheless, there are few studies on how well RPE tracks with the heart rate over repeated training sessions in elite soccer players. Therefore, we aimed to quantify the within-participant correlations between variability in session-RPE (sRPE) and the heart rate in elite male soccer players, and to determine whether the playing position moderated these correlations. The field-based training of four central defenders, four wide defenders, six central midfielders, two wide midfielders and three attackers from an elite English Premier League squad were monitored over an entire in-season competitive period, giving a total of 1010 individual training sessions for study. Correlations between session-RPE and heart rates were quantified using a within-participant model. The correlation between changes in sRPE and heart rates was r = 0.75 (95% CI: 0.71–0.78). This correlation remained high across the various player positions (wide-defender, r = 0.81; central-defender, r = 0.74; wide midfielder, r = 0.70; central midfielder, r = 0.70; attacker, r = 0.84; P < 0.001). The correlation between changes in RPE and heart rates, measured during a season-long period of field-based training, is high in a sample of elite soccer players.

Choroidal thickness using EDI-OCT in adult-onset vitelliform macular dystrophy.

BackgroundTo compare choroidal thickness in patients with adult-onset foveomacular vitelliform dystrophy (AOFVD) with healthy subjects and to correlate choroidal thickness with age, gender and spherical equivalent.MethodsA prospective, observational study of 37 eyes (15 eyes in AOFVD group and 22 eyes in control group) was conducted. Images were acquired by enhanced depth imaging optical coherence tomography (EDI-OCT). Choroidal thickness measurements were performed in the subfoveal region and at 500, 1000 and 1500 µm intervals from the foveal center to nasal and to temporal regions for subsequent averaging of values.ResultsThe AOFVD group consisted of four male eyes (28.6 %) and 10 female eyes (71.4 %); age was 33–62 years; spherical equivalent (SE) ranged from −1.50 to 1.50 spherical diopters (SD); mean subfoveal thickness was 325.6 µm, ranging from 186 to 420 µm; and the average of thicknesses was 309.4 µm, ranging from 188 to 413 µm. The control group consisted of 12 male eyes (54.5 %) and 10 female eyes (45.5 %); age was 27–62 years; SE ranged from −2.50 to 0.50 SD; subfoveal thickness was 294.8 µm, ranging from 213 to 481 µm; and the average of thicknesses was 279.4 µm, ranging from 201 to 458 µm.ConclusionsThe AOFVD group and the control group showed similar choroidal thickness by correcting for age, SE and gender. Not yet known, completely, which biochemical and vascular flow alterations of the choroid, and which functional RPE changes may play a role in the pathogenesis of this disease. EDI-OCT, incorporated in some SD-OCT devices, allows higher quality assessment of the choroid. In this article, choroidal thickness of patients with AOFVD, a rare disease with a not fully understood pathogenesis, was assessed.

The Effect of Exertion on Heart Rate and Rating of Perceived Exertion in Acutely Concussed Individuals.

ObjectiveResearch suggests that one physiological effect of concussion is a disruption in regulation of autonomic nervous system control that affects the balance between parasympathetic and sympathetic output. While changes in heart rate after concussion have been observed, the nature of the heart rate change during progressive exercise has not been well evaluated in acutely symptomatic patients. Additionally, little is known about the relationship between HR and RPE in this population.MethodsWe compared changes in heart rate and perceived effort during graded treadmill exertion in recently concussed patients to elucidate the effect of brain injury on cardiovascular response to exercise. Resting HR, HR on exercise initiation, and changes in HR and RPE during the Buffalo Concussion Treadmill Test (BCTT) were compared on two test visits: When patients were symptomatic (acute) and after recovery. Results were compared with the test-retest results obtained from a control group consisting of healthy, non-concussed individuals.ResultsPatients had a significantly lower HR at onset of exercise when acutely concussed as compared to when recovered and reported greater perceived exertion at every exercise intensity level when symptomatic, despite exercising at lower workloads, than when recovered. Sympathetic response to increased exertion was not affected by concussion - HR increased in response to exercise at a comparable rate in both tests. These differences observed in response to exercise between the first BCTT and follow-up evaluation in initially concussed patients were not present in non-concussed individuals.ConclusionOur results suggest that during the acute phase after concussion, acutely concussed patients demonstrated an impaired ability to shift from parasympathetic to sympathetic control over heart rate at the onset of exercise. Changes in the autonomic nervous system after concussion may be more complex than previously reported. Continued evaluation of autonomic regulatory effects in the acute phase after concussion is warranted.

Half-Dose Verteporfin Photodynamic Therapy (hdPDT) in the Treatment of Central Serous Chorioretinopathy

To estimate the efficacy and safety profile of half-dose photodynamic therapy (hdPDT) for treating central serous chorioretinopathy (CSC). An interventional, retrospective case series of patients with CSC (symptoms ≧ 3 months) receiving half-dose PDT (3 mg/m2 verteporfin). The ophthalmic examination at baseline and at 8 and 16 weeks after treatment included slit-lamp biomicroscopy, indirect ophthalmoscopy, measurement of intraocular pressure (IOP), ETDRS best-corrected visual acuity (BCVA), Amsler grid screening and contrast visual acuity (CVA). Fluorescein angiography (FA), autofluorescence (FAF) and optical coherence tomography (OCT) were measured at each visit. Central macular thickness (CMT) was measured automatically. 12 eyes of 12 patients (10 male and 2 female patients; mean age 46.6 ± 7.91 years) were included in this study. Anatomical resolution was obtained in 10 eyes (83.4 %) at week 16, but 2 eyes (16.6 %) exhibited persistent SRD throughout the follow-up period. Baseline CMT decreased from initially 330.1 µm ± 131.3 to 205.6 µm ± 97.6 (p = 0.034) at week 8 and to 220.3 µm ± 120.1 (p = 0.05) at week 16. Visual acuity (number of total letters read) significantly improved from initially 82.8 ± 11.5 to 86.8 ± 13.9 at week 8 and 91.3 ± 13.8 at week 16 (p = 0.012). Contrast visual acuity (calculated decimal visual acuity) significantly improved from initially 0.14 ± 0.09 to 0.38 ± 0.28 (p = 0.002) at week 16. After therapy, no significant changes in RPE could be detected with FAF and no ocular adverse events were observed. PDT with half-dose verteporfin resulted in reduced leakage in FA, enhanced visual acuity and resolution of subretinal fluid in OCT in patients with CSC, with no detected side effects of treatment.

Thermal and Cardiovascular Strain Mitigate the Potential Benefit of Carbohydrate Mouth Rinse During Self-Paced Exercise in the Heat.

Purpose: To determine whether a carbohydrate mouth rinse can alter self-paced exercise performance independently of a high degree of thermal and cardiovascular strain.Methods: Eight endurance-trained males performed two 40-km cycling time trials in 35°C, 60% RH while swilling a 20-ml bolus of 6.5% maltodextrin (CHO) or a color- and taste-matched placebo (PLA) every 5 km. Heart rate, power output, rectal temperature (Tre), and mean skin temperature (Tsk) were recorded continuously; cardiac output, oxygen uptake (VO2), mean arterial pressure (MAP), and perceived exertion (RPE) were measured every 10 min.Results: Performance time and mean power output were similar between treatments, averaging 63.9 ± 3.2 and 64.3 ± 2.8 min, and 251 ± 23 and 242 ± 18 W in CHO and PLA, respectively. Power output, stroke volume, cardiac output, MAP, and VO2 decreased during both trials, increasing slightly or remaining stable during a final 2-km end-spurt. Tre, Tsk, heart rate, and RPE increased throughout exercise similarly with both treatments. Changes in RPE correlated with those in Tre (P < 0.005) and heart rate (P < 0.001).Conclusions: These findings suggest that carbohydrate mouth rinsing does not improve ~1-h time trial performance in hot-humid conditions, possibly due to a failure in down-regulating RPE, which may be influenced more by severe thermal and cardiovascular strain.

In Vivo Imaging of Subretinal Bleb-Induced Outer Retinal Degeneration in the Rabbit.

To analyze the morphologic effects of subretinal blebs in rabbits using real-time imaging by spectral-domain optical coherence tomography (SD-OCT), infrared-confocal scanning laser ophthalmoscopy (IR-cSLO), and blue-light fundus autofluorescence (BAF). Subretinal blebs of PBS or balanced salt solution (BSS) were induced in albino or pigmented rabbits using a transvitreal pars plana technique. Spectral-domain optical coherence tomography, IR-cSLO, and BAF were done at multiple intervals for up to 12 weeks after subretinal bleb injection. The morphologic effects were compared with histologic analysis on hematoxylin-eosin-stained sections of the neurosensory retina and on flat-mounts of phalloidin-labeled RPE. Scans of SD-OCT of the normal rabbit posterior segment revealed 11 bands including six layers of the photoreceptors. Subretinal blebs of PBS or BSS caused acute swelling of the neurosensory retina followed by gradual atrophy. Outer retinal thickness was significantly reduced with pronounced degeneration of all the photoreceptor OCT layers. En face IR-cSLO showed a hyperreflective area corresponding to the progressive photoreceptor degeneration, whereas BAF revealed both hyper- and hypofluorescent changes in the RPE layer. The in vivo results were confirmed by histology and on subretinal flatmounts demonstrating extensive photoreceptor loss and disruption of the RPE mosaic. Subretinal blebs induce pronounced photoreceptor degeneration and RPE changes in the rabbit as demonstrated by in vivo imaging using SD-OCT, IR-cSLO, and BAF.

Segmentation of Retinal Layers in Sjögren–Larsson Syndrome

Segmentation of Retinal Layers in Sjögren–Larsson Syndrome

A Submaximal Test for the Assessment of Knee Extensor Endurance Capacity

We aimed to develop an undemanding test for endurance capacity of the knee extensor muscles, which can also be applied to frail participants. We hypothesized 1) that the first objective indications for peripheral fatigue during incremental unilateral repetitive isometric knee extensor contractions could be used to assess a fatigue threshold (FT), 2) that torque at FT would depend on training status, and 3) that this torque could easily be sustained for 30 min. Five trained and five untrained participants performed 5-min bouts of 60 repetitive contractions (3-s on and 2-s off). Torque, set at 25% maximal voluntary contraction (MVC), was increased by 5% MVC in subsequent bouts. The highest torque for which rectified surface EMG remained stable during the bout was defined as the FT. On separate occasions, 30-min bouts were performed at and above the FT to assess sustainable torque. Changes in gas exchange parameters, HR, and RPE were monitored to corroborate FT. At FT (RPE = 5.7 ± 1.7), torque was higher (P < 0.05) in trained (41.4% ± 5.8% MVC) than in untrained participants (30.5% ± 1.8% MVC). Sustainable torque was ∼4% higher than (P < 0.05) and significantly related to FT (r(2) = 0.79). When torque was increased by 5% MVC, significant increases in rectified surface EMG and V˙O2 were found. During incremental knee extensor contractions, FT could be assessed at a submaximal exercise intensity. FT was higher in trained than in untrained participants and was related to exercise sustainability. With the use of FT, changes in endurance capacity of single muscle groups can potentially also be determined in frail participants for whom exercise performed until exhaustion is unwarranted.

Fundusautofluoreszenz bei der trockenen Form der altersbedingten Makuladegeneration – Bedeutung für die Prognose

Fundus autofluorescence is a novel technique that gives us information about the RPE cells by evaluating the distribution of lipofuscin in the retina. The purpose of our study was to evaluate the diagnostic abilities of OCT, RTVue and fundus autofluorescence in predicting the progression of dry AMD. In our study 37 dry AMD patients were enrolled: 22 of them with druses and 15 with developed geographic atrophy. They all underwent complete ophthalmological examinations including OCT and autofluorescence. We used the RTVue OCT programmes HD line, Cross line, EMM5 and EMM5 progression in all cases. The autofluorescence was recorded with the help of the Canon CX1 fundus camera. OCT images in the AMD patients with dry AMD and large druses showed typical undulations in the RPE/choroid line and occasionally drusenoid detachment of the RPE. Autofluorescence showed different patterns. The confluent reticular autofluorescence was associated with the development of neovascular membranes. In geographic atrophy patient OCTs showed diminished retinal thickness measured with EMM5. On autofluorescence the findings at the border zone atrophic/normal retina were of particular importance. The diffuse increased autofluorescence in that area was considered to be a sign for further atrophy progression. Our results point out that OCT in combination with autofluorescence is important in following the progression of dry AMD. Pathological autofluorescence at the border of atrophic lesions is an important sign for disease activity. Although both OCT and autofluorescence visualise the changes in RPE, autofluorescence is of key importance in predicting the development of the disease.

Prior Eccentric Exercise Augments Muscle Pain and Perception of Effort During Cycling Exercise

This study examined the effects of exercise-induced muscle damage (EIMD) on the physiological and perceptual responses to 30 minutes of submaximal cycling at 60% of oxygen consumption (VO2 peak). Ten participants completed two 30-minute bouts of cycling, one before and one 48 hours after performance of strenuous (24 contractions with 120% of concentric 1-repeition maximum) eccentric exercise. Eccentric exercise resulted in a significant delayed-onset muscle pain (1.6±1.6 mm to 44.8±20 mm on a 100-mm visual analog scale; P<0.001) and a 15% (P<0.001) reduction in maximal strength 48 hours after exercise. Ratings of quadriceps muscle pain (1.99±0.42 vs. 3.30±0.56; P=0.003) and perceived exertion (RPE; 13.0±0.30 vs. 13.8±0.61; P=0.02) were elevated during cycling after EIMD at identical work rates. No changes were observed in VO2 (29.6±4.6 vs. 30.2±4.4 mL/kg/min; P=0.41), heart rate (154±15 vs. 155±9 beats/min; P=0.58), and ventilation (57.2±12.1 vs. 59.8±12.7 L/min; P=0.13) during exercise after EIMD. The mean change in RPE was significantly correlated (r=0.56; P<0.01) with the change in muscle pain during cycling and delayed-onset pain during resistance exercise (r=0.86; P<0.01), but did not correlate with changes in VO2, heart rate, ventilation, and maximal strength. These findings indicate the elevations in RPE after EIMD are likely a consequence of the EIMD with the most likely explanation being an increase in localized pain before and during cycling exercise.

Inhibition of PVR with a Tyrosine Kinase Inhibitor, Dasatinib, in the Swine

We tested the efficacy of dasatinib, a Food and Drug Administration (FDA)-approved tyrosine kinase inhibitor, to prevent proliferative vitreoretinopathy (PVR). The effect of dasatinib on RPE sheet growth was determined by measuring enlargement of cultured RPE sheets in the presence or absence of dasatinib. Epithelial-mesenchymal transition (EMT) of RPE cells was assessed by expression of S100A4. A scratch wound assay, cell number count, and type I collagen contraction assay were used to examine the effect of dasatinib on migration, proliferation, and extracellular matrix (ECM) contraction, respectively. Our swine model of experimental PVR with green fluorescent protein-positive (GFP+) RPE cells was used to assess the efficacy of dasatinib in preventing traction retinal detachment (TRD) caused by PVR. Full-field electroretinography and histologic examination were used to determine the retinal toxicity of dasatinib. Dasatinib prevented RPE sheet growth, cell migration, proliferation, EMT, and ECM contraction in a concentration-dependent manner. 0.1 μM dasatinib inhibited nearly 80% of vitreous fluid-stimulated collagen gel contraction. Dasatinib also prevented TRD caused by PVR in vivo. Only 1/11 eyes had a TRD in the presence of dasatinib, while all 11 controls eyes had a TRD. Dasatinib did not cause any detectable toxicity of the retina. Dasatinib significantly inhibited PVR-related RPE changes in vitro and prevented TRD in an experimental PVR model in the swine without any detectable toxicity. Our data suggested that dasatinib may be effective in the prevention of PVR.

Indocyanine Green-Assisted Internal Limiting Membrane Peeling in Macular Hole Surgery: A Meta-Analysis

BackgroundThe opinion of application of indocyanine green (ICG) in the macular hole surgery was contradictory. Here we conducted a meta-analysis to evaluate the effect of in internal limiting membrane (ILM) peeling for macular hole surgery.Methods and FindingsWe searched electronic databases for comparative studies published before July 2012 of ILM peeling with and without ICG. Twenty-two studies including 1585 eyes were included. Visual acuity (VA) improvement, including the postoperative rate of ≥20/40 VA gained (OR, 0.65; 95% CI, 0.43 to 0.97; P = 0.033) and increased LogMAR (WMD, −0.09; 95% CI, −0.16 to −0.02; P = 0.011), was less in the ICG group. The risk of visual field defects was greater in the ICG group than in the non-ICG group. There was no significant difference in the rate of anatomical outcomes between ILM peeling procedures performed with and without ICG. RPE changes and other postoperative complications were not significantly different between the ICG and non-ICG groups. An additional analysis showed that the VA improvement of the ICG group was less than the non-ICG group only within the first year of follow up. A subgroup analysis showed that the rate of VA improvement was lower in the ICG group than in other adjuncts group. A higher rate of secondary closure and less VA improvement were observed in a high proportion (>0.1%) of the ICG group. A sensitivity analysis after the randomized-controlled trials were excluded from the meta-analysis demonstrated no differences compared with the overall results.ConclusionsThis meta-analysis demonstrated that there is no evidence of clinical superiority in outcomes for ICG-assisted ILM peeling procedure over the non-ICG one. The toxicity of ICG should be considered when choosing the various staining methods.