Exercise in Diabetic Nephropathy: Protective Effects and Molecular Mechanism.

Diabetic nephropathy (DN) is a serious complication of diabetes, and its progression is influenced by factors like oxidative stress, inflammation, cell death, and fibrosis. Compared to drug treatment, exercise offers a cost-effective and low-risk approach to slowing down DN progression. Through multiple ways and mechanisms, exercise helps to control blood sugar and blood pressure and reduce serum creatinine and albuminuria, thereby alleviating kidney damage. This review explores the beneficial effects of exercise on DN improvement and highlights its potential mechanisms for ameliorating DN. In-depth understanding of the role and mechanism of exercise in improving DN would pave the way for formulating safe and effective exercise programs for the treatment and prevention of DN.

Plasma Biomarkers of Evolving Encephalopathy and Brain Injury in Neonates with Hypoxic-Ischemic Encephalopathy.

OBJECTIVE: The objective of the study was to evaluate the relationship between a panel of candidate plasma biomarkers and (1) death or severe brain injury on magnetic resonance imaging (MRI) and (2) dysfunctional cerebral pressure autoregulation as a measure of evolving encephalopathy. STUDY DESIGN: Neonates with moderate-to-severe hypoxic-ischemic encephalopathy (HIE) at 2 level IV neonatal intensive care units were enrolled into this observational study. Patients were treated with therapeutic hypothermia (TH) and monitored with continuous blood pressure monitoring and near-infrared spectroscopy. Cerebral pressure autoregulation was measured by the hemoglobin volume phase (HVP) index; a higher HVP index indicates poorer autoregulation. Serial blood samples were collected during TH and assayed for Tau, glial fibrillary acidic protein, and neurogranin. MRIs were assessed using National Institutes of Child Health and Human Development scores. The relationships between the candidate biomarkers and (1) death or severe brain injury on MRI (defined as a National Institutes of Child Health and Human Development score of ≥ 2B) and (2) autoregulation were evaluated using bivariate and adjusted logistic regression models. RESULTS: Sixty-two patients were included. Elevated Tau levels on days 2-3 of TH were associated with death or severe injury on MRI (aOR: 1.06, 95% CI: 1.03-1.09; aOR: 1.04, 95% CI: 1.01-1.06, respectively). Higher Tau was also associated with poorer autoregulation (higher HVP index) on the same day (P = .022). CONCLUSIONS: Elevated plasma levels of Tau are associated with death or severe brain injury by MRI and dysfunctional cerebral autoregulation in neonates with HIE. Larger-scale validation of Tau as a biomarker of brain injury in neonates with HIE is warranted.

The Utility of Cerebral Autoregulation Indices in Detecting Severe Brain Injury Varies by Cooling Treatment Phase in Neonates with Hypoxic-Ischemic Encephalopathy.

Identifying the hemodynamic range that best supports cerebral perfusion using near infrared spectroscopy (NIRS) autoregulation monitoring is a potential physiologic marker for neonatal hypoxic-ischemic encephalopathy (HIE) during therapeutic hypothermia. However, an optimal autoregulation monitoring algorithm has not been identified for neonatal clinical medicine. We tested whether the hemoglobin volume phase (HVP), hemoglobin volume (HVx), and pressure passivity index (PPI) identify changes in autoregulation that are associated with brain injury on MRI or death. The HVP measures the phase difference between a NIRS metric of cerebral blood volume, the total hemoglobin (THb), and mean arterial blood pressure (MAP) at the frequency of maximum coherence. The HVx is the correlation coefficient between MAP and THb. The PPI is the percentage of coherent MAP-DHb (difference between oxygenated and deoxygenated hemoglobin, a marker of cerebral blood flow) epochs in a chosen time period. Neonates cooled for HIE were prospectively enrolled in an observational study in two neonatal intensive care units. In analyses adjusted for study site and encephalopathy level, all indices detected relationships between poor autoregulation in the first 6 h after rewarming with a higher injury score on MRI. Only HVx and PPI during hypothermia and the PPI during rewarming identified autoregulatory dysfunction associated with a poor outcome independent of study site and encephalopathy level. Our findings suggest that the accuracy of mathematical autoregulation algorithms in detecting the risk of brain injury or death may depend on temperature and postnatal age. Extending autoregulation monitoring beyond the standard 72 h of therapeutic hypothermia may serve as a method to provide personalized care by assessing the need for and efficacy of future therapies after the hypothermia treatment phase.

Integrative metagenomic and metabolomic analyses reveal the role of gut microbiota in antibody-mediated renal allograft rejection.

BACKGROUND: Antibody-mediated rejection (AMR) remains one of the major barriers for graft survival after kidney transplantation. Our previous study suggested a gut microbiota dysbiosis in kidney transplantation recipients with AMR. However, alternations in gut microbial function and structure at species level have not been identified. In the present study, we investigated the metagenomic and metabolic patterns of gut microbiota in AMR patients to provide a comprehensive and in-depth understanding of gut microbiota dysbiosis in AMR. METHODS: We enrolled 60 kidney transplantation recipients, 28 showed AMR and 32 were non-AMR controls with stable post-transplant renal functions. Shotgun sequencing and untargeted LC/MS metabolomic profiling of fecal samples were performed in kidney transplantation recipients with AMR and controls. RESULTS: Totally, we identified 311 down-regulated and 27 up-regulated gut microbial species associated with AMR after kidney transplantation, resulting in the altered expression levels of 437 genes enriched in 22 pathways, of which 13 were related to metabolism. Moreover, 32 differential fecal metabolites were found in recipients with AMR. Among them, alterations in 3b-hydroxy-5-cholenoic acid, L-pipecolic acid, taurocholate, and 6k-PGF1alpha-d4 directly correlated with changes in gut microbial species and functions. Specific differential fecal species and metabolites were strongly associated with clinical indexes (Cr, BUN, etc.), and could distinguish the recipients with AMR from controls as potential biomarkers. CONCLUSIONS: Altogether, our findings provided a comprehensive and in-depth understanding of the correlation between AMR and gut microbiota, which is important for the etiological and diagnostic study of AMR after kidney transplantation.

Exploratory Assessment of the Relationship Between Hemoglobin Volume Phase Index, Magnetic Resonance Imaging, and Functional Outcome in Neonates with Hypoxic-Ischemic Encephalopathy.

BACKGROUND/OBJECTIVE: Near-infrared spectroscopy (NIRS)-based measures of cerebral autoregulation (CAR) can potentially identify neonates with hypoxic-ischemic encephalopathy (HIE) who are at greatest risk of irreversible brain injury. However, modest predictive abilities have precluded previously described metrics from entering clinical care. We previously validated a novel autoregulation metric in a piglet model of induced hypotension called the hemoglobin volume phase index (HVP). The objective of this study was to evaluate the clinical ability of the HVP to predict adverse outcomes neonates with HIE. METHODS: This is a prospective study of neonates with HIE who underwent therapeutic hypothermia (TH) at a level 4 neonatal intensive care unit (NICU). Continuous cerebral NIRS and mean arterial blood pressure (MAP) from indwelling arterial catheters were measured during TH and through rewarming. Multivariate autoregressive process was used to calculate the coherence between MAP and the sum total of the oxy- and deoxygenated Hb densities (HbT), a surrogate measure of cerebral blood volume (CBV). The HVP was calculated as the cosine-transformed phase shift at the frequency of maximal MAP-HbT coherence. Brain injury was assessed by neonatal magnetic resonance imaging (MRI), and developmental outcomes were assessed by the Bayley Scales of Infant Development (BSID-III) at 15-30 months. The ability of the HVP to predict (a) death or severe brain injury by MRI and (b) death or significant developmental delay was assessed using logistic regression analyses. RESULTS: In total, 50 neonates with moderate or severe HIE were monitored. Median HVP was higher, representing more dysfunctional autoregulation, in infants who had adverse outcomes. After adjusting for sex and encephalopathy grade at presentation, HVP at 21-24 and 24-27 h of life predicted death or brain injury by MRI (21-24 h: OR 8.8, p = 0.037; 24-27 h: OR 31, p = 0.011) and death or developmental delay at 15-30 months (21-24 h: OR 11.8, p = 0.05; 24-27 h: OR 15, p = 0.035). CONCLUSIONS: Based on this pilot study of neonates with HIE, HVP merits further study as an indicator of death or severe brain injury on neonatal MRI and neurodevelopmental delay in early childhood. Larger studies are warranted for further clinical validation of the HVP to evaluate cerebral autoregulation following HIE.

Meta-analysis of genome-wide association studies of adult height in East Asians identifies 17 novel loci.

Human height is associated with risk of multiple diseases and is profoundly determined by an individual's genetic makeup and shows a high degree of ethnic heterogeneity. Large-scale genome-wide association (GWA) analyses of adult height in Europeans have identified nearly 180 genetic loci. A recent study showed high replicability of results from Europeans-based GWA studies in Asians; however, population-specific loci may exist due to distinct linkage disequilibrium patterns. We carried out a GWA meta-analysis in 93 926 individuals from East Asia. We identified 98 loci, including 17 novel and 81 previously reported loci, associated with height at P < 5 × 10(-8), together explaining 8.89% of phenotypic variance. Among the newly identified variants, 10 are commonly distributed (minor allele frequency, MAF > 5%) in Europeans, with comparable frequencies with in Asians, and 7 single-nucleotide polymorphisms are with low frequency (MAF < 5%) in Europeans. In addition, our data suggest that novel biological pathway such as the protein tyrosine phosphatase family is involved in regulation of height. The findings from this study considerably expand our knowledge of the genetic architecture of human height in Asians.

Deep whole-genome sequencing of 100 southeast Asian Malays.

Whole-genome sequencing across multiple samples in a population provides an unprecedented opportunity for comprehensively characterizing the polymorphic variants in the population. Although the 1000 Genomes Project (1KGP) has offered brief insights into the value of population-level sequencing, the low coverage has compromised the ability to confidently detect rare and low-frequency variants. In addition, the composition of populations in the 1KGP is not complete, despite the fact that the study design has been extended to more than 2,500 samples from more than 20 population groups. The Malays are one of the Austronesian groups predominantly present in Southeast Asia and Oceania, and the Singapore Sequencing Malay Project (SSMP) aims to perform deep whole-genome sequencing of 100 healthy Malays. By sequencing at a minimum of 30× coverage, we have illustrated the higher sensitivity at detecting low-frequency and rare variants and the ability to investigate the presence of hotspots of functional mutations. Compared to the low-pass sequencing in the 1KGP, the deeper coverage allows more functional variants to be identified for each person. A comparison of the fidelity of genotype imputation of Malays indicated that a population-specific reference panel, such as the SSMP, outperforms a cosmopolitan panel with larger number of individuals for common SNPs. For lower-frequency (<5%) markers, a larger number of individuals might have to be whole-genome sequenced so that the accuracy currently afforded by the 1KGP can be achieved. The SSMP data are expected to be the benchmark for evaluating the value of deep population-level sequencing versus low-pass sequencing, especially in populations that are poorly represented in population-genetics studies.

Nine loci for ocular axial length identified through genome-wide association studies, including shared loci with refractive error.

Refractive errors are common eye disorders of public health importance worldwide. Ocular axial length (AL) is the major determinant of refraction and thus of myopia and hyperopia. We conducted a meta-analysis of genome-wide association studies for AL, combining 12,531 Europeans and 8,216 Asians. We identified eight genome-wide significant loci for AL (RSPO1, C3orf26, LAMA2, GJD2, ZNRF3, CD55, MIP, and ALPPL2) and confirmed one previously reported AL locus (ZC3H11B). Of the nine loci, five (LAMA2, GJD2, CD55, ALPPL2, and ZC3H11B) were associated with refraction in 18 independent cohorts (n = 23,591). Differential gene expression was observed for these loci in minus-lens-induced myopia mouse experiments and human ocular tissues. Two of the AL genes, RSPO1 and ZNRF3, are involved in Wnt signaling, a pathway playing a major role in the regulation of eyeball size. This study provides evidence of shared genes between AL and refraction, but importantly also suggests that these traits may have unique pathways.

Pathways-driven sparse regression identifies pathways and genes associated with high-density lipoprotein cholesterol in two Asian cohorts.

Standard approaches to data analysis in genome-wide association studies (GWAS) ignore any potential functional relationships between gene variants. In contrast gene pathways analysis uses prior information on functional structure within the genome to identify pathways associated with a trait of interest. In a second step, important single nucleotide polymorphisms (SNPs) or genes may be identified within associated pathways. The pathways approach is motivated by the fact that genes do not act alone, but instead have effects that are likely to be mediated through their interaction in gene pathways. Where this is the case, pathways approaches may reveal aspects of a trait's genetic architecture that would otherwise be missed when considering SNPs in isolation. Most pathways methods begin by testing SNPs one at a time, and so fail to capitalise on the potential advantages inherent in a multi-SNP, joint modelling approach. Here, we describe a dual-level, sparse regression model for the simultaneous identification of pathways and genes associated with a quantitative trait. Our method takes account of various factors specific to the joint modelling of pathways with genome-wide data, including widespread correlation between genetic predictors, and the fact that variants may overlap multiple pathways. We use a resampling strategy that exploits finite sample variability to provide robust rankings for pathways and genes. We test our method through simulation, and use it to perform pathways-driven gene selection in a search for pathways and genes associated with variation in serum high-density lipoprotein cholesterol levels in two separate GWAS cohorts of Asian adults. By comparing results from both cohorts we identify a number of candidate pathways including those associated with cardiomyopathy, and T cell receptor and PPAR signalling. Highlighted genes include those associated with the L-type calcium channel, adenylate cyclase, integrin, laminin, MAPK signalling and immune function.

Prediction of outcome of hypoxic-ischemic encephalopathy in newborns undergoing therapeutic hypothermia using heart rate variability.

OBJECTIVE: To assess the use of continuous heart rate variability (HRV) as a predictor of brain injury severity in newborns with moderate to severe HIE that undergo therapeutic hypothermia. STUDY DESIGN: Two cohorts of newborns (n1 = 55, n2 = 41) with moderate to severe hypoxic-ischemic encephalopathy previously treated with therapeutic hypothermia. HRV was characterized by root mean square in the short time scales (RMSS) during therapeutic hypothermia and through completion of rewarming. A logistic regression and Naïve Bayes models were developed to predict the MRI outcome of the infants using RMSS. The encephalopathy grade and gender were used as control variables. RESULTS: For both cohorts, the predicted outcomes were compared with the observed outcomes. Our algorithms were able to predict the outcomes with an area under the receiver operating characteristic curve of about 0.8. CONCLUSIONS: HRV assessed by RMSS can predict severity of brain injury in newborns with HIE.

Hepatic Klf10-Fh1 axis promotes exercise-mediated amelioration of NASH in mice.

Exercise is an effective non-pharmacological strategy for the treatment of nonalcoholic steatohepatitis (NASH), but the underlying mechanism needs further investigation. Kruppel-like factor 10 (Klf10) is a transcriptional factor that is expressed in multiple tissues including liver, whose role in NASH is not well defined. In our study, exercise induces hepatic Klf10 expression through the cAMP/PKA/CREB pathway. Hepatocyte-specific knockout of Klf10 (Klf10LKO) increases lipid accumulation, cell death, inflammation and fibrosis in NASH diet-fed mice and reduces the protective effects of treadmill exercise against NASH, while hepatocyte-specific overexpression of Klf10 (Klf10LTG) works in concert with exercise to reduce NASH in mice. Mechanistically, Klf10 promotes the expression of fumarate hydratase 1 (Fh1), thereby reducing fumarate accumulation in hepatocytes. This decreases the trimethyl (me3) levels of histone 3 lysine 4 (H3K4me3) on lipogenic genes promoters to attenuate lipogenesis, thus ameliorating free fatty acids (FFAs)-induced hepatocytes steatosis, apoptosis, insulin resistance and blunting dysfunctional hepatocytes-mediated activation of macrophages and hepatic stellate cells. Therefore, by regulating the Fh1/fumarate/H3K4me3 pathway, Klf10 acts as a downstream effector of exercise to combat NASH.

Shifts in Intestinal Metabolic Profile Among Kidney Transplantation Recipients with Antibody-Mediated Rejection.

Background: Antibody-mediated rejection (AMR) is emerging as the main cause of graft loss after kidney transplantation. Our previous study revealed the gut microbiota alternation associated with AMR in kidney transplant recipients, which was predicted to affect the metabolism-related pathways. Methods: To further investigate the shifts in intestinal metabolic profile among kidney transplantation recipients with AMR, fecal samples from kidney transplant recipients and patients with end-stage renal disease (ESRD) were subjected to untargeted LC-MS-based metabolomics. Results: A total of 86 individuals were enrolled in this study, including 30 kidney transplantation recipients with AMR, 35 kidney transplant recipients with stable renal function (KT-SRF), and 21 participants with ESRD. Fecal metabolome in patients with ESRD and kidney transplantation recipients with KT-SRF were parallelly detected as controls. Our results demonstrated that intestinal metabolic profile of patients with AMR differed significantly from those with ESRD. A total of 172 and 25 differential metabolites were identified in the KT-AMR group, when compared with the ESRD group and the KT-SRF group, respectively, and 14 were common to the pairwise comparisons, some of which had good discriminative ability for AMR. KEGG pathway enrichment analysis demonstrated that the different metabolites between the KT-AMR and ESRD groups or between KT-AMR and KT-SRF groups were significantly enriched in 33 or 36 signaling pathways, respectively. Conclusion: From the metabolic point of view, our findings may provide key clues for developing effective diagnostic biomarkers and therapeutic targets for AMR after kidney transplantation.

Whole genome characterization of a multidrug-resistant hypervirulent Pasteurella multocida with a new drug-resistant plasmid.

Pasteurella multocida (P. multocida) is a zoonotic bacterium that can cause diseases in a variety of animals. It was divided into 5 serogroups, and serogroup A is mainly prevalent in avian hosts. We isolated a virulent and multidrug-resistant P. multocida strain from Guangdong duck liver and named it PMWSG-4 (GenBank accession no. CP077723.1). To understand the pathogenicity of this strain, the pathogenicity test was carried out with mice and ducks. The results showed that PMSWG-4 was highly pathogenic to ducks and mice, and the LD50 is 4.5 and 73 CFU, respectively. In order to study its genetic characteristics, pathogenicity, and relationship with the host, we performed a whole genome sequencing. The genome size of the isolated PMWSG-4 was 2.38 Mbp, with a G+C content of 40.3%, and coding 2,313 Coding DNA Sequence (CDS). The genome carries 162 potential virulence-associated genes, 32 different drug resistance phenotypes, 102 genes possibly involved in pathogen-host interaction, 2 gene island groups, and 4 prophages. In addition, we also found a new drug-resistant plasmid from strain PMWSG-4, named pXL001 (GenBank accession no. CP077724.1). After verified, the plasmid is a new plasmid carrying the floR florfenicol resistance gene. The whole genome is of great significance for further studying the pathogenesis and genetic characteristics of duck-derived P. multocida.

Cdo1-Camkk2-AMPK axis confers the protective effects of exercise against NAFLD in mice.

Exercise is an effective non-pharmacological strategy for ameliorating nonalcoholic fatty liver disease (NAFLD), but the underlying mechanism needs further investigation. Cysteine dioxygenase type 1 (Cdo1) is a key enzyme for cysteine catabolism that is enriched in liver, whose role in NAFLD remains poorly understood. Here, we show that exercise induces the expression of hepatic Cdo1 via the cAMP/PKA/CREB signaling pathway. Hepatocyte-specific knockout of Cdo1 (Cdo1LKO) decreases basal metabolic rate of the mice and impairs the effect of exercise against NAFLD, whereas hepatocyte-specific overexpression of Cdo1 (Cdo1LTG) increases basal metabolic rate of the mice and synergizes with exercise to ameliorate NAFLD. Mechanistically, Cdo1 tethers Camkk2 to AMPK by interacting with both of them, thereby activating AMPK signaling. This promotes fatty acid oxidation and mitochondrial biogenesis in hepatocytes to attenuate hepatosteatosis. Therefore, by promoting hepatic Camkk2-AMPK signaling pathway, Cdo1 acts as an important downstream effector of exercise to combat against NAFLD.

Construction and Immunogenicity of a Recombinant Pseudorabies Virus Expressing SARS-CoV-2-S and SARS-CoV-2-N.

Coronavirus (CoV) is an important pathogen of humans and animals, which can infect humans or animals through the respiratory mucosal route. Syndrome coronavirus 2 (SARS-CoV-2) is quite similar to syndrome coronavirus (SARS-CoV) with the same receptor, angiotensin-converting enzyme 2 (ACE2). The S and N proteins are the most important protective antigens of the SARS-CoV-2. The S protein on the viral membrane mediates the virus attachment with the host cells, and the N protein is the most abundant expression during infection. In this study, the recombinant viruses expressing the S and N proteins of SARS-CoV-2 were successfully constructed by Red/ET recombinant technology using Pseudorabies virus (PRV) strain Bartha-K61 as a vector. Genetic stability and growth kinetics analysis showed that the recombinant viruses rPRV-SARS-CoV-2-S and rPRV-SARS-CoV-2-N had similar genetic stability and proliferation characteristics to the parental PRV. The immunoassay results showed that mice immunized with recombinant viruses could produce total IgG antibodies. Therefore, PRV is feasible and promising as a viral vector to express SARS-CoV-2-S and SARS-CoV-2-N genes. This study can provide a reference for future research on live vector vaccines for domestic animals, pets, and wild animals.

The Effect of the Antimicrobial Peptide Plectasin on the Growth Performance, Intestinal Health, and Immune Function of Yellow-Feathered Chickens.

The goal of the study was to test the effects of an antibiotic substitute, plectasin, on the growth performance, immune function, intestinal morphology and structure, intestinal microflora, ileal mucosal layer construction and tight junctions, ileal immune-related cytokines, and blood biochemical indices of yellow-feathered chickens. A total of 1,500 one-day-old yellow-feathered chicks were randomly divided into four dietary treatment groups with five replicates in each group and 75 yellow-feathered chicks in each replication, as follows: basal diet (group A); basal diet supplemented with 10 mg enramycin/kg of diet (group B), basal diet supplemented with 100 mg plectasin/kg of diet (group C), and basal diet supplemented with 200 mg plectasin/kg of diet (group D). It was found that the dietary antimicrobial peptide plectasin could improve the ADG and had better F/G for the overall period of 1-63 days. Dietary plectasin can enhance H9N2 avian influenza virus (AIV) and Newcastle disease virus (NDV) antibody levels of yellow-feathered chickens at 21, and 35 days of age. Dietary plectasin can enhance the intestine structure, inhibit Escherichia coli and proinflammatory cytokines in the ileum, and ameliorate the blood biochemical indices of yellow-feathered chickens at 21 days of age. This study indicates that the antimicrobial peptide plectasin has beneficial effects on the growth performance, intestinal health and immune function of yellow-feathered chickens.

Aerobic exercise relieved vascular cognitive impairment via NF-κB/miR-503/BDNF pathway.

OBJECTIVE: To investigate the mechanism of aerobic exercise in the relief of vascular cognitive impairment (VCI). MATERIALS AND METHODS: Latency of Water Maze test was measured at sham, 2VO, 2VO+EX groups. miR-503 and BDNF mRNA levels were detected by quantitative real-time PCR. Protein levels of NF-κB and BDNF were detected by Western blot. Hippocampal neuron cell apoptosis was detected by flow cytometry. Luciferase reporter assay was conducted to investigate the effect of miR-503 on BDNF. RESULTS: Latency of Water Maze test in 2VO group was longer than Sham group, while exercise shortened the latency. The expressions of NF-κB and miR-503 in 2VO group were higher than Sham group, while exercise downregulated the expressions. BDNF level in 2VO group were downregulated than Sham group, while exercise upregulated the levels. We also found NF-κB, miR-503 levels were upregulated and BDNF level was downregulated in OGD-treated hippocampal neuron cells. In addition, OGD increased the expression of NF-κB and miR-503, and the expression of miR-503 was downregulated when treated with NF-κB inhibitor (PDTC). Moreover, we confirmed BDNF was a direct target of miR-503. OGD decreased the expression of BDNF, while miR-503 inhibitor reversed this effect. And we proved OGD induced cell apoptosis via NF-κB/miR-503/BDNF. Finally, in rats injected with miR-503 inhibitor, latency of Water Maze test was shortened, miR-503 expression was downregulated, and BDNF level was upregulated. While in rats injected with miR-503 mimic, the results were the opposite. CONCLUSION: Aerobic exercise relieved VCI via NF-κB/miR-503/BDNF pathway.

Automatic retinal interest evaluation system (ARIES).

In recent years, there has been increasing interest in the use of automatic computer-based systems for the detection of eye diseases such as glaucoma, age-related macular degeneration and diabetic retinopathy. However, in practice, retinal image quality is a big concern as automatic systems without consideration of degraded image quality will likely generate unreliable results. In this paper, an automatic retinal image quality assessment system (ARIES) is introduced to assess both image quality of the whole image and focal regions of interest. ARIES achieves 99.54% accuracy in distinguishing fundus images from other types of images through a retinal image identification step in a dataset of 35342 images. The system employs high level image quality measures (HIQM) to perform image quality assessment, and achieves areas under curve (AUCs) of 0.958 and 0.987 for whole image and optic disk region respectively in a testing dataset of 370 images. ARIES acts as a form of automatic quality control which ensures good quality images are used for processing, and can also be used to alert operators of poor quality images at the time of acquisition.

Local patch reconstruction framework for optic cup localization in glaucoma detection.

Optic cup localization/segmentation has attracted much attention from medical imaging researchers, since it is the primary image component clinically used for identifying glaucoma, which is a leading cause of blindness. In this work, we present an optic cup localization framework based on local patch reconstruction, motivated by the great success achieved by reconstruction approaches in many computer vision applications recently. Two types of local patches, i.e. grids and superpixels are used to show the variety, generalization ability and robustness of the proposed framework. Tested on the ORIGA clinical dataset, which comprises of 325 fundus images from a population-based study, both implementations under the proposed frameworks achieved higher accuracy than the state-of-the-art techniques.