Assessing the efficacy of palliative radiation treatment schemes for locally advanced squamous cell carcinoma of the head and neck: a meta-analysis.

Background: The objective to assess the outcomes from different palliative radiotherapy (RT) schedules in incurable head and neck cancer (HNC), to evaluate if there is a relationship between RT dose, technique, and fractionation with tumor response in contrast to the occurrence of adverse effects. Materials and methods: Eligible studies were identified on Medline, Embase, the Cochrane Library, and annual meetings proceedings through June 2020. Following PRISMA and MOOSE guidelines, a cumulative meta-analysis of studies for overall response rate (ORR), overall survival (OS), progression-free survival (PFS), pain/dysphagia relief, and toxicity was performed. A meta-regression analysis was done to assess if there is a connection between RT dose, schedule, and technique with ORR. Results: Twenty-eight studies with 1,986 patients treated with palliative RT due to incurable HNC were included. The median OS was 6.5 months [95% confidence interval (CI): 5.6-7.4], and PFS was 3.6 months (95% CI: 2.7-4.3). The ORR, pain and dysphagia relief rates were 72% (95% CI: 0.6-0.8), 83% (95% CI: 52-100%), and 75% (95% CI: 52-100%), respectively. Conventional radiotherapy (2D-RT) or conformational radiotherapy (3D-RT) use were significantly associated with a higher acute toxicity rate (grade ≥ 3) than intensity-modulated radiation therapy (IMRT) or stereotactic body radiation therapy (SBRT). On meta-regression analyses, the total biological effective doses (BED) of RT (p = 0.001), BED > 60 Gy10 (p = 0.001), short course (p = 0.01) and SBRT (p = 0.02) were associated with a superior ORR. Conclusions: Palliative RT achieves tumor response and symptom relief in incurable HNC patients. Short course RT of BED > 60 Gy using IMRT could improve its therapeutic ratio. SBRT should be considered when available.

Near-infrared spectroscopy-derived muscle V̇O2${\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ kinetics after moderate running exercise in healthy males: reliability and associations with parameters of aerobic fitness.

NEW FINDINGS: What is the central question of this study? What is the reliability of near-infrared spectroscopy-derived muscle oxygen uptake ( mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ) kinetics following running exercise and what is the relationship between the time constant of mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ off-kinetics and parameters of aerobic fitness? What is the main finding and its importance? The time constant of mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ kinetics in gastrocnemius following moderate running exercise presents good to excellent reliability. In addition, it was well correlated with parameters of aerobic fitness, such as maximal speed of an incremental test, ventilatory threshold and pulmonary V̇O2${\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ on-kinetics. Therefore, near-infrared spectroscopy-derived muscle oxidative capacity together with other physiological measurements may allow a concomitant local and systemic analysis of the components of the oxidative system. ABSTRACT: Near-infrared spectroscopy-derived muscle oxygen uptake ( mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ) kinetics following single-joint exercise has been used to assess muscle oxidative capacity. However, little evidence is available on the use of this technique following whole-body exercise. Therefore, this study aimed to assess the reliability of the NIRS-derived mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ kinetics following running exercise and to investigate the relationship between the time constant of mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ off-kinetics ( τmV̇O2$\tau {\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ) and parameters of aerobic fitness. After an incremental test to determine V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ , first (VT1 ) and second (VT2 ) ventilatory thresholds, and maximal speed (Smax ), 13 males (age = 21 ± 4 years; V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$  = 55.9 ± 3.4 ml kg-1  min-1 ) performed three sets (two on the first day and one on a subsequent day) of two repetitions of 6-min running exercise at 90%VT1 . The pulmonary V̇O2${\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ( pV̇O2${\rm{p}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ) on-kinetics and mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ off-kinetics in gastrocnemius were assessed. τmV̇O2$\tau {\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ presented no systematic change and satisfactory reliability (the standard error of the measurement (SEM) and intraclass correlation coefficient of 4.21 s and 0.49 for between transitions; and 2.65 s and 0.74 averaging τmV̇O2$\tau {\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ within each time set), with no difference (P > 0.3) between the within- (SEM = 2.92 s) and between-day variability (SEM = 2.78 s and 2.19 s between first vs. third set, and second vs. third set, respectively). τmV̇O2$\tau {\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ (28.5 ± 4.17 s) correlated significantly (P < 0.05) with Smax (r = -0.66), VT1 (r = -0.64) and time constant of the p V̇O2${\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ on-kinetics (r = 0.69). These findings indicate that NIRS-derived mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ kinetics in the gastrocnemius following moderate running exercise is a useful and reliable parameter to assess muscle oxidative capacity.

Is Functional Overreaching or Acute Fatigue the Key to the Effects of Concentrated Block Training in Running?

ABSTRACT: Borszcz, FK, Vieira, MT, Tramontin, AF, Visentainer, LH, and Costa, VP. Is functional overreaching or acute fatigue the key to the effects of concentrated block training in running? J Strength Cond Res 36(12): 3485-3496, 2022-This study examined the effects of 5 consecutive days of high- and moderate-intensity training on performance and physiological measures in moderately trained individuals. The relationship of the training organization with the state of overreaching and acute fatigue was investigated. Twenty-four male soldiers (age, 19.3 ± 0.4 years; V̇o2peak, 58.7 ± 3.8 ml·kg-1·min-1) were assigned to 2 training groups for 5 consecutive days of either high- or moderate-intensity training. The subjects underwent incremental and 12-minute time trial tests before, immediately after, 1 and 2 weeks after training. The high- and moderate-intensity sessions were 30 minutes in duration and performed at fixed velocities of 13.3 and 10 km·h-1 (near second and first ventilatory thresholds), respectively. Acute fatigue and overreaching criteria were set as concomitant nonimpairment and impairment, respectively, in the incremental peak velocity and 12-minute time trial performances at posttest immediately after the training block. Data analyses were completed using hierarchical Bayesian's models. In subjects who wer trained at moderate intensity, no performance impairment occurred (i.e., acute fatigue); for the high-intensity training, 5 subjects showed impairment in performance and were classified as overreached. Only in subjects who were acutely fatigued, clear beneficial effects were observed in incremental test peak velocity and 12-minute time trial performances. In moderately trained runners, a block of 5 consecutive days of moderate-intensity training was demonstrated to be a useful strategy for the improvement of performance. However, high-intensity training does not seem to be a safe strategy because of the observations of overreaching and inferior probabilities of performance improvements.

Ergogenic Effects of Photobiomodulation on Performance in the 30-Second Wingate Test: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

ABSTRACT: Molina Correa, JC, Padoin, S, Varoni, PR, Demarchi, MC, Flores, LJ, Nampo, FK, and de Paula Ramos, S. Ergogenic effects of photobiomodulation on performance in the 30-second Wingate test: A randomized, double-blind, placebo-controlled, crossover study. J Strength Cond Res 36(7): 1901-1908, 2022-The purpose of this study was to evaluate the ergogenic effects of red light (630 nm) photobiomodulation on anaerobic capacity in the Wingate test. Sixteen healthy and physically active male volunteers (21.71 ± 2.49 years of age, body mass index between 18.5 and 24.9 kg/m2) participated in this randomized, double-blind, placebo-controlled, crossover study. The subjects performed 3 Wingate test sessions, with a 48-hour interval between tests. In the first session (baseline session, BS), a Wingate test was performed to evaluate the initial performance. Subjects were paired by performance in the BS and allocated through a draw to receive either the phototherapy (630 nm, 4.6 J/cm2, 6 J per point, 16 points, light-emitting diode [LED] session) or placebo intervention (PLA session) in the second test session. In the third test session, a crossover intervention was performed. The repeated-measures analysis of variance test, followed by Bonferroni post hoc test or Friedman test with Dunn's post hoc test (p < 0.05) and Cohen's d statistic were used for comparisons. The LED session with phototherapy promoted an increase in performance in peak power (p < 0.05), relative power (p < 0.05), RPMpeak (p < 0.05), and peak velocity (p < 0.05), as well as total displacement (p < 0.01) compared with PLA. The mean power (p < 0.05), relative power (p < 0.05), RPMmean (p < 0.01), and mean velocity (p < 0.01) were higher in the LED session than those of BS. We concluded that phototherapy improves performance in Wingate anaerobic exercise, possibly due to large effects on the anaerobic alactic metabolism.

Anti-Obesity and Anti-Diabetic Effects of Ishige okamurae.

Obesity is associated with several health complications and can lead to the development of metabolic syndrome. Some of its deleterious consequences are related to insulin resistance, which adversely affects blood glucose regulation. At present, there is a growing concern regarding healthy food consumption, owing to awareness about obesity. Seaweeds are well-known for their nutritional benefits. The brown alga Ishige okamurae (IO) has been studied as a dietary supplement and exhibits various biological activities in vitro and in vivo. The bioactive compounds isolated from IO extract are known to possess anti-obesity and anti-diabetic properties, elicited via the regulation of lipid metabolism and glucose homeostasis. This review focuses on IO extract and its bioactive compounds that exhibit therapeutic effects through several cellular mechanisms in obesity and diabetes. The information discussed in the present review may provide evidence to develop nutraceuticals from IO.

Modulation of exercise-induced muscular damage and hyperalgesia by different 630 nm doses of light-emitting diode therapy (LEDT) in rats.

We compared the acute effects of different doses of 630 nm light-emitting diode therapy (LEDT) on skeletal muscle inflammation and hyperalgesia in rats submitted to exercise-induced muscle damage (EIMD). Wistar rats were divided into five experimental groups (n = 5-8/group): sedentary control (CON); exercise + passive recovery (PR); and exercise + LEDT (1.2 J/cm2, 1.8 J; 4.2 J/cm2, 6.3 J; 10.0 J/cm2, 15 J). After 100 min of swimming, the rats in the LEDT groups were exposed to phototherapy on the triceps surae muscle. For mechanical hyperalgesia evaluation, paw withdrawal threshold was assessed before and 24 h after swimming. Immediately after hyperalgesia tests, blood samples were collected to analyze creatine kinase (CK) activity and the soleus muscle was removed for histological and tumor necrosis factor (TNF)-α immunohistological analyses. In all LEDT groups, plasma CK activity was reduced to levels similar to those measured in the CON group. Paw withdrawal threshold decreased in the PR group (- 11.9 ± 1.9 g) when compared to the CON group (2.2 ± 1.5 g; p < 0.01) and it was attenuated in the group LEDT 4.2 J/cm2 (- 3.3 ± 2.4 g, p < 0.05). Less leukocyte infiltration and edema and fewer necrotic areas were found in histological sections of soleus muscle in LEDT (4.2 J/cm2) and LEDT (10.0 J/cm2) groups compared to the PR group. Also, LEDT (4.2 J/cm2) and LEDT (10.0 J/cm2) groups showed less immunostaining for TNF-α in macrophages or areas with necrosis of muscle fibers compared to the PR group. LEDT (4.2 J/cm2, 6.3 J)-reduced muscle inflammation and nociception in animals submitted to EIMD.

Ishige okamurae Extract and Its Constituent Ishophloroglucin A Attenuated In Vitro and In Vivo High Glucose-Induced Angiogenesis.

Diabetes is associated with vascular complications, such as impaired wound healing and accelerated vascular growth. The different clinical manifestations, such as retinopathy and nephropathy, reveal the severity of enhanced vascular growth known as angiogenesis. This study was performed to evaluate the effects of an extract of Ishige okamurae (IO) and its constituent, Ishophloroglucin A (IPA) on high glucose-induced angiogenesis. A transgenic zebrafish (flk:EGFP) embryo model was used to evaluate vessel growth. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), gap closure, transwell, and Matrigel® assays were used to analyze the proliferation, migration, and capillary formation of EA.hy926 cells. Moreover, protein expression were determined using western blotting. IO extract and IPA suppressed vessel formation in the transgenic zebrafish (flk:EGFP) embryo. IPA attenuated cell proliferation, cell migration, and capillary-like structure formation in high glucose-treated human vascular endothelial cells. Further, IPA down regulated the expression of high glucose-induced vascular endothelial growth factor receptor 2 (VEGFR-2) and downstream signaling molecule cascade. Overall, the IO extract and IPA exhibited anti-angiogenic effects against high glucose-induced angiogenesis, suggesting their potential for use as therapeutic agents in diabetes-related angiogenesis.

Diphlorethohydroxycarmalol Isolated from Ishige okamurae Represses High Glucose-Induced Angiogenesis In Vitro and In Vivo.

Diabetes mellitus causes abnormalities of angiogenesis leading to vascular dysfunction and serious pathologies. Diphlorethohydroxycarmalol (DPHC), which is isolated from Ishige okamurae, is well known for its bioactivities, including antihyperglycemic and protective functions against diabetes-related pathologies. In the present study, the inhibitory effect of DPHC on high glucose-induced angiogenesis was investigated on the human vascular endothelial cell line EA.hy926. DPHC inhibited the cell proliferation, cell migration, and tube formation in cells exposed to 30 mM of glucose to induce angiogenesis. Furthermore, the effect of DPHC against high glucose-induced angiogenesis was evaluated in zebrafish embryos. The treatment of embryos with DPHC suppressed high glucose-induced dilation in the retinal vessel diameter and vessel formation. Moreover, DPHC could inhibit high glucose-induced vascular endothelial growth factor receptor 2 (VEGFR-2) expression and its downstream signaling cascade. Overall, these findings suggest that DPHC is actively involved in the suppression of high glucose-induced angiogenesis. Hence, DPHC is a potential agent for the development of therapeutics against angiogenesis induced by diabetes.

Cone Beam Computed Tomography-based Evaluation of the Anterior Teeth Position Changes obtained by Passive Self-ligating Brackets.

AIM: The objective of this study was to evaluate the anterior teeth position changes obtained by passive self-ligating brackets using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Twenty patients with a mean age of 16.5 years, class I malocclusion, constricted maxillary arch, and teeth crowding above 5 mm were enrolled in this study, and treated by passive orthodontic self-ligating brackets. A sequence of stainless steel thermoset wire was implemented with ending wire of 0.019" × 0.025". The CBCT and dental casts were obtained prior to the installation of orthodontic appliances (T1), and 30 days after rectangular steel wire 0.019" × 0.025" installation (T2). The measurements in CBCT were performed with the Anatomage software, and the dental casts were evaluated with a digital caliper rule with an accuracy of 0.01 mm. RESULTS: The CBCT data demonstrated mean buccal inclination of the upper and lower central incisors ranging from 6.55° to 7.24° respectively. The upper and lower lateral incisors ranged from 4.90° to 8.72° respectively. The lower canines showed an average increase of 3.88° in the buccal inclination and 1.96 mm in the transverse intercuspal distance. The upper canines showed a negative inclination with mean average of -0.36°, and an average increase of 0.82 mm in the transverse distance, with negative correlation with the initial crowding. CONCLUSION: Treatment with passive self-ligating brackets without obtaining spaces increases buccal inclination of the upper and lower incisors with no correlation with the amount of initial teeth crowding. The intercanine distance tends to a small increase showing different inclinations between the arches. CLINICAL SIGNIFICANCE: When taking into account the self-ligating brackets, the amount of initial dental crowding is not a limitation factor that could increase the buccal inclination of the anterior teeth.

Hyperbaric oxygen therapy for choroidal neovascularization: a pilot study.

INTRODUCTION: Choroidal neovascularization (CNV) is one of the leading causes of blindness worldwide and affects patients with wet age-related macular degeneration (AMD). Its natural course may lead to impaired central vision and macular fibrosis. Even VEGF blockade, currently the best available treatments for CNV, may fail to improve vision. Hyperbaric oxygen (HBO2) therapy may be an alternative or ancillary treatment for CNV. METHODS: AMD patients with active CNV underwent 10 daily sessions of HBO2 at 2 atmospheres absolute (atm abs) for 120 minutes each session. After the end of the sessions, patients with clinical or tomographical signs of CNV activity underwent standard anti-VEGF treatment. RESULTS: Seven patients (average age 73) underwent 10 daily 120-minute sessions of HBO2 at 2 atm abs. After the sessions, five patients underwent intravitreal injection of bevacizumab. Average follow-up was 150 days. Average CNV area at baseline was 14.42 mm2; average CNV greatest linear diameter at baseline was 4.56 mm. Statistical analysis of variance (ANOVA) was performed for central retinal thickness and volume mean percentage changes post-treatment. At the end of follow up, five patients showed anatomical improvement, one patient maintained anatomical aspect and one patient showed anatomical worsening. CONCLUSION: HBO2 may be a safe and tolerable treatment option for patients with active CNV, potentially delaying its progression, as monotherapy or in combination with intravitreal bevacizumab.

Migration of silver nanoparticles from silver decorated graphene oxide to other carbon nanostructures.

Decoration of graphene oxide (GO) sheets with Ag nanoparticles has been demonstrated using a simple sonication technique. By changing the ratio between Ag-decorated-GO and GO, a series of Ag-decorated-GO samples with different Ag loadings were synthesized. These Ag-decorated-GO samples were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) spectroscopy, thermal gravimetric analysis (TGA), and differential scanning calorimetric (DSC) techniques. TEM analysis showed that Ag nanoparticles were evenly distributed on GO sheets, and the size analysis of the particles using multiple TEM images indicated that Ag nanoparticles have an average size of 6-7 nm. TEM analysis also showed that Ag nanoparticles migrated from Ag-decorated-GO to later-added GO sheets. In XRD, all the Ag-decorated GO samples showed the characteristic peaks related to GO and face-centered-cubic (fcc) Ag. Thermal analysis showed peaks related to the combustion of graphitic carbon shifted to lower temperatures after GO sheets were decorated with Ag nanoparticles. In addition, further experiments performed using Ag-decorated-GO and multiwalled carbon nanotubes (MWNTs) confirmed that Ag nanoparticles migrated from Ag-decorated-GO to later-added carbon nanotubes without a noticeable coalescence of Ag nanoparticles.

Visible-light photoconversion of carbon dioxide into organic acids in an aqueous solution of carbon dots.

Carbon "quantum" dots (or carbon dots) have emerged as a new class of optical nanomaterials. Beyond the widely reported bright fluorescence emissions in carbon dots, their excellent photoinduced redox properties that resemble those found in conventional semiconductor nanostructures are equally valuable, with photon-electron conversion applications from photovoltaics to CO2 photocatalytic reduction. In this work we used gold-doped carbon dots from controlled synthesis as water-soluble catalysts for a closer examination of the visible-light photoconversion of CO2 into small organic acids, including acetic acid (for which the reduction requires many more electrons than that for formic acid) and, more interestingly, for the significantly enhanced photoconversion with higher CO2 pressures over an aqueous solution of the photocatalysts. The results demonstrate the nanoscale semiconductor-equivalent nature of carbon dots, with excellent potential in energy conversion applications.

Chemical Method for Recovery and Regeneration of Graphene Oxide.

Graphene oxide (GO) has been developed as a very effective medium for filtration and removal of microbial contaminants in fuel. GO is capable of filtering out microorganisms without needing micrometer and submicrometer pores for filtration. Our previous studies showed that microorganisms are attracted by GO and bind irreversibly to GO without promoting bacterial growth. Therefore, GO was tested as a filter medium to remove microorganisms in fuel. The characterization results showed that GO removed microbes in diesel fuel with >99% efficiency. However, the synthesis of GO using Hummers' method is labor intensive and a time-consuming. We present in this paper an economical, less labor intensive and a simple chemical approach to recover GO after it has been used as a filtration medium for the removal of microorganisms in fuels. In the GO recovery process, microbial and fuel contaminated GO is washed with hexane to remove any fuel from the GO sample. The hexane-washed GO is further washed with acetone and mixed with ethanol to kill and remove any microorganisms. After washing with ethanol, the GO sample is sonicated in water to remove impurities and re-establish the oxygen functionalities. The final recovered-GO (rec-GO) is obtained after removing water by rotary evaporation. The chemical characterization of rec-GO showed that rec-GO is similar in both chemical and physical properties compared to freshly synthesized-GO (as-syn-GO). Rec-GO was shown to perform similarly to as-syn-GO in filtration of biocontaminated fuel. We estimate that our rec-GO is at least 90% cheaper than high quality commercially available GO.

Modeling the influence of propionic acid concentration and pH on the kinetics of Salmonella Typhimurium.

Salmonella Typhimurium is a foodborne pathogen often found in the poultry production chain. Antibiotics have been used to reduce S. Typhimurium contamination in poultry aviaries and improve chicken growth. However, antibiotics were banned in several countries. Alternatively, organic acids, such as propionic acid (PA), can control pathogens. This study determined the PA minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and mathematically modeled S. Typhimurium growth/inactivation kinetics under the influence of PA at different pH values (4.5, 5.5, and 6.5) which are within the pH range of the chicken gastrointestinal tract. The PA MIC against S. Typhimurium was pH-dependent, resulting in 5.0, 3.5 and 9.0 mM undissociated PA at pH 4.5, 5.5, and 6.5, respectively. The Baranyi and Roberts and the Weibull model fit growth and inactivation data well, respectively. Secondary models were proposed. The validated model predicted 3-log reduction of S. Typhimurium in 3 h at 68.2 mM of undissociated PA and pH 4.5. The models presented a good capacity to describe the kinetics of S. Typhimurium subjected to PA, representing a useful tool to predict PA antibacterial action depending on the pH.

Automated Identification of Different Severity Levels of Diabetic Retinopathy Using a Handheld Fundus Camera and Single-Image Protocol.

Purpose: To evaluate the performance of artificial intelligence (AI) systems embedded in a mobile, handheld retinal camera, with a single retinal image protocol, in detecting both diabetic retinopathy (DR) and more-than-mild diabetic retinopathy (mtmDR). Design: Multicenter cross-sectional diagnostic study, conducted at 3 diabetes care and eye care facilities. Participants: A total of 327 individuals with diabetes mellitus (type 1 or type 2) underwent a retinal imaging protocol enabling expert reading and automated analysis. Methods: Participants underwent fundus photographs using a portable retinal camera (Phelcom Eyer). The captured images were automatically analyzed by deep learning algorithms retinal alteration score (RAS) and diabetic retinopathy alteration score (DRAS), consisting of convolutional neural networks trained on EyePACS data sets and fine-tuned using data sets of portable device fundus images. The ground truth was the classification of DR corresponding to adjudicated expert reading, performed by 3 certified ophthalmologists. Main Outcome Measures: Primary outcome measures included the sensitivity and specificity of the AI system in detecting DR and/or mtmDR using a single-field, macula-centered fundus photograph for each eye, compared with a rigorous clinical reference standard comprising the reading center grading of 2-field imaging protocol using the International Classification of Diabetic Retinopathy severity scale. Results: Of 327 analyzed patients (mean age, 57.0 ± 16.8 years; mean diabetes duration, 16.3 ± 9.7 years), 307 completed the study protocol. Sensitivity and specificity of the AI system were high in detecting any DR with DRAS (sensitivity, 90.48% [95% confidence interval (CI), 84.99%-94.46%]; specificity, 90.65% [95% CI, 84.54%-94.93%]) and mtmDR with the combination of RAS and DRAS (sensitivity, 90.23% [95% CI, 83.87%-94.69%]; specificity, 85.06% [95% CI, 78.88%-90.00%]). The area under the receiver operating characteristic curve was 0.95 for any DR and 0.89 for mtmDR. Conclusions: This study showed a high accuracy for the detection of DR in different levels of severity with a single retinal photo per eye in an all-in-one solution, composed of a portable retinal camera powered by AI. Such a strategy holds great potential for increasing coverage rates of screening programs, contributing to prevention of avoidable blindness. Financial Disclosures: F.K.M. is a medical consultant for Phelcom Technologies. J.A.S. is Chief Executive Officer and proprietary of Phelcom Technologies. D.L. is Chief Technology Officer and proprietary of Phelcom Technologies. P.V.P. is an employee at Phelcom Technologies.

Advancing healthcare with artificial intelligence: diagnostic accuracy of machine learning algorithm in diagnosis of diabetic retinopathy in the Brazilian population.

BACKGROUND: In healthcare systems in general, access to diabetic retinopathy (DR) screening is limited. Artificial intelligence has the potential to increase care delivery. Therefore, we trained and evaluated the diagnostic accuracy of a machine learning algorithm for automated detection of DR. METHODS: We included color fundus photographs from individuals from 4 databases (primary and specialized care settings), excluding uninterpretable images. The datasets consist of images from Brazilian patients, which differs from previous work. This modification allows for a more tailored application of the model to Brazilian patients, ensuring that the nuances and characteristics of this specific population are adequately captured. The sample was fractionated in training (70%) and testing (30%) samples. A convolutional neural network was trained for image classification. The reference test was the combined decision from three ophthalmologists. The sensitivity, specificity, and area under the ROC curve of the algorithm for detecting referable DR (moderate non-proliferative DR; severe non-proliferative DR; proliferative DR and/or clinically significant macular edema) were estimated. RESULTS: A total of 15,816 images (4590 patients) were included. The overall prevalence of any degree of DR was 26.5%. Compared with human evaluators (manual method of diagnosing DR performed by an ophthalmologist), the deep learning algorithm achieved an area under the ROC curve of 0.98 (95% CI 0.97-0.98), with a specificity of 94.6% (95% CI 93.8-95.3) and a sensitivity of 93.5% (95% CI 92.2-94.9) at the point of greatest efficiency to detect referable DR. CONCLUSIONS: A large database showed that this deep learning algorithm was accurate in detecting referable DR. This finding aids to universal healthcare systems like Brazil, optimizing screening processes and can serve as a tool for improving DR screening, making it more agile and expanding care access.

Optical Coherence Tomography Angiographic Evaluation of Macular Vessel Density in Diabetic Macular Edema After Intravitreal Dexamethasone Implants: A Prospective Interventional Trial.

BACKGROUND AND OBJECTIVE: The goal of this study was to assess macular vascular density evolution, macular thickness, and functional outcomes after intravitreal dexamethasone implants for diabetic macular edema. PATIENTS AND METHODS: Vascular density was evaluated with optical coherence tomography (OCT) angiography in 21 eyes. Macular thickness was evaluated with structural OCT. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. Macular vessel density in the superficial capillary plexus was evaluated with OCT angiography and quantified in areas with no fluid, allowing a more accurate measurement and eliminating the segmentation bias in areas with intra-retinal fluid. Such a methodology was possible by positioning the scans only in areas with no fluid before and after the implant. The absence of fluid in these areas was confirmed by three experienced evaluators using both the B-scan and the en face. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. RESULTS: At 30, 60, and 90 days after implantation, there was improvement in macular perfusion in areas without fluid after intravitreal dexamethasone implantation, accompanied by reduced macular thickness and improved visual acuity (P < .001). However, there was no improvement in contrast sensitivity after treatment. CONCLUSIONS: Improved macular perfusion after treatment with intravitreal dexamethasone implantation may be associated with modulation of leukostasis, when the release of cytokines leads to capillary endothelial damage and obstruction of the micro-vasculature, leading to impaired capillary perfusion and ischemic damage. Despite the anatomical and functional findings demonstrated, further studies are needed to prove the relationship between the inflammatory mechanisms of diabetic macular edema and its relationship with macular perfusion and functional aspects. [Ophthalmic Surg Lasers Imaging Retina 2023;54(3):174-182.].

Acute physiological responses to eccentric cycling: a systematic review and meta-analysis.

INTRODUCTION: Eccentric cycling (ECCCYC) has attracted considerable interest due to its potential applicability for exercise treatment/training of patients with poor exercise tolerance as well as healthy and trained individuals. Conversely, little is known about the acute physiological responses to this exercise modality, thus challenging its proper prescription. This study aimed to provide precise estimates of the acute physiological responses to ECCCYC in comparison to traditional concentric cycling (CONCYC). EVIDENCE ACQUISITION: Searches were performed until November 2021 using the PubMed, Embase, and ScienceDirect databases. Studies that examined individuals' cardiorespiratory, metabolic, and perceptual responses to ECCCYC and CONCYC sessions were included. Bayesian multilevel meta-analysis models were used to estimate the population mean difference between acute physiological responses from ECCCYC and CONCYC bouts. Twenty-one studies were included in this review. EVIDENCE SYNTHESIS: The meta-analyses showed that ECCCYC induced lower cardiorespiratory (i.e., V̇O2, V̇E, and HR), metabolic (i.e., [BLa]), and perceptual (i.e., RPE) responses than CONCYC performed at the same absolute power output, while greater cardiovascular strain (i.e., greater increases in HR, Q, MAP, [norepinephrine], and lower SV) was detected when compared to CONCYC performed at the same V̇O2. CONCLUSIONS: The prescription of ECCCYC based on workloads used in the CONCYC sessions may be considered safe and, therefore, feasible for the rehabilitation of individuals with poor exercise tolerance. However, the prescription of ECCCYC based on the V̇O2 obtained during CONCYC sessions should be conducted with caution, especially in clinical settings, since there is a high probability of additional cardiovascular overload in this condition.