Stress-responsive miRNAome of Glycine max (L.) Merrill: molecular insights and way forward.

MAIN CONCLUSION: Analysis of stress-associated miRNAs of Glycine max (L.) Merrill reveals wider ramifications of small RNA-mediated (conserved and legume-specific miRNAs) gene regulatory foot prints in molecular adaptive responses. MicroRNAs (miRNAs) are indispensable components of gene regulatory mechanism of plants. Soybean is a crop of immense commercial potential grown worldwide for its edible oil and soy meal. Intensive research efforts, using the next generation sequencing and bioinformatics techniques, have led to the identification and characterization of numerous small RNAs, especially microRNAs (miRNAs), in soybean. Furthermore, studies have unequivocally demonstrated the significance of miRNAs during the developmental processes and various stresses in soybean. In this review, we summarize the current state of understanding of miRNA-based abiotic and biotic stress responses in soybean. In addition, the molecular insights gained from the stress-related soybean miRNAs have been compared to the miRNAs of other crops, especially legumes, and the core commonalities have been highlighted, though differences among them were not ignored. Nature of response of soybean-derived conserved miRNAs during various stresses was also analyzed to gain deeper insights regarding sRNAome-based defense responses. This review further provides way forward in legume small RNA transcriptomics based on the adaptive responses of soybean and other legume-derived miRNAs.

Diversity and Tissue Preference of Osmotolerant Bacterial Endophytes Associated with Pearl Millet Genotypes Having Differential Drought Susceptibilities.

Genetic and functional diversity of osmotolerant bacterial endophytes colonizing the root, stem, and leaf tissues of pearl millet genotypes differing in their drought susceptibility was assessed. Two genotypes of pearl millet, viz., the drought tolerant genotype TT-1 and the drought susceptible genotype PPMI-69, were used in the present study. Diazotrophs were found to be the predominant colonizers, followed by the Gram positive bacteria in most of the tissues of both the genotypes. Higher proportion of bacterial endophytes obtained from the drought tolerant genotype was found to be osmotolerant. Results of 16S rRNA gene-ARDRA analysis grouped 50 of the highly osmotolerant isolates into 16 clusters, out of which nine clusters had only one isolate each, indicating their uniqueness. One cluster had 21 isolates and remaining clusters were represented by isolates ranging from two to four. The representative isolates from each cluster were identified, and Bacillus was found to be the most prevalent osmotolerant genera with many different species. Other endophytic bacteria belonged to Pseudomonas sp., Stenotrophomonas sp., and Macrococcus caseolyticus. High phylogenetic diversity was observed in the roots of the drought tolerant genotype while different tissues of the drought susceptible genotype showed less diversity. Isolates of Bacillus axarquiensis were present in all the tissues of both the genotypes of pearl millet. However, most of the other endophytic bacteria showed tissue/genotype specificity. With the exception of B. axarquiensis and B. thuringiensis, rest all the species of Bacillus were found colonizing only the drought-tolerant genotype; while M. caseolyticus colonized all the tissues of only the drought susceptible genotype. There was high incidence of IAA producers and low incidence of ACC deaminase producers among the isolates from the root tissues of the drought-tolerant genotype while reverse was the case for the drought-susceptible genotype. Thus, host played an important role in the selection of endophytes based on both phylogenetic and functional traits.

What is the diagnostic yield of colonoscopy in patients with a referral diagnosis of constipation in South Africa?

BACKGROUND: Constipation is a common problem for referral to surgical and colorectal units. Its association with colorectal cancer is controversial. Some authors have found an increased incidence while others have not. The aim of this study is to investigate the incidence of colorectal cancer (CRC) and other significant colonoscopic pathologies in patients undergoing colonoscopy for constipation. METHOD: All colonoscopy reports for constipation were retrieved from our database from January 2011 to 30 June 2014. Data extracted included demographics, colonoscopic findings and adequacy of bowel preparation. Exclusion criteria included patients with other symptoms known to be associated with colonic neoplasia such as lower GIT bleeding, loss of weight, patients with associated anaemia, those with abnormalities on imaging, patients with personal or family history of colorectal cancers or colorectal polyps and patients with inflammatory bowel disease. The primary outcome was the presence of neoplasia at colonoscopy and the secondary outcomes were other colonoscopy findings. RESULTS: A total of 985 colonoscopies were performed from January 2011 to June 2014 of which 144 were done for a referral diagnosis of constipation. Eighty eight (61.1%) were female. Their mean age was 58.6 + 13.8 years (range 19-95 years). There were 61 (42.4%) African patients, 38 (26.4%) White, 33 (22.9%) Asians and 12 (8.3%) Coloured patients. Eighty seven (60.4%) patients had a normal colonoscopy, 20 (13.9%) diverticular disease, 14 (9.7%) polyps of which 6 (4.2%) were neoplastic, and 9 (6.3%) had colorectal cancer. CONCLUSION: Constipation is associated with CRC. The presence of constipation should be a criterion for colonoscopy regardless of age or any other associated clinical features.

Auditing surgical service provision at a South African tertiary institution: Implications for the development of district services.

BACKGROUND: The optimal management of resources within South African state hospitals has been hampered by a paucity of data due to a lack of robust auditing information systems. This study reviews the use of a Hybrid Electronic Medical Record (HEMR) system to capture and aggregate data pertaining to the inpatient service demands on a South African tertiary surgical service. This dataset was used to analyse the appropriateness of tertiary surgical resource utilisation. METHOD: The HEMR system was implemented at Greys Hospital, in the city of Pietermaritzburg, Kwa-Zulu Natal, South Africa on 1 January 2013. Inpatient data pertaining to surgical admissions and operative interventions were captured prospectively. Following an 18-month study period, the data were extracted, aggregated and analysed. The district referral hospitals were mapped, and district surgical procedures performed within the tertiary center were identified and quantified. Results: 7314 patients were admitted and managed by the tertiary surgical service during the study period. The median patient age was 33 years (IQR 6.5-42.4 years). 59.7% were male and 40.3% were female. General, trauma and paediatric surgical admissions constituted 54.8%, 28.6% and 16.6% respectively. Emergency admissions constituted 62.4% and elective admissions 37.6%. Referral sources were captured for 6653 (91%) of the cohort. 4338 (65.2%) patients were referred from district hospitals. The district hospital (Northdale) closest to Greys Hospital was responsible for 1675 (25.2%) of surgical referrals. 4174 operative procedures were performed during the study period, 54.7% performed as an emergency, 34.1% electively and 11.2% semi-electively. The median waiting time for emergency operative intervention was 535 minutes (IQR 130-663). A total of 1272 (30.5%) operative procedures performed were assessed as district-level operations. The time intervals of 07:00-07:59 and 17:00-17:59 were identified as the time periods during which the least number of emergency procedures were performed in the operating theatres. CONCLUSION: The HEMR system enabled the Pietermaritzburg Metropolitan Department of Surgery to quantify the burden of surgical disease and map district referral patterns. Thirty percent of operative procedures performed were assessed as district-level operations. Potentially correctable deficits identified within the tertiary center were lengthy delays to emergency surgery and non-optimal theatre utilisation periods.

Differentiation of stem cells derived from carious teeth into dopaminergic-like cells.

AIM: To investigate whether dental pulp stem cells from carious teeth (DPSCs-CT) can differentiate into functional dopaminergic-like (DAergic) cells and provide an alternative cell source in regenerative medicine. METHODOLOGY: Dental pulp stem cells from healthy (DPSCs) and carious teeth (DPSCs-CT) were isolated from young donors. Both cell lines were expanded in identical culture conditions and subsequently differentiated towards DAergic-like cells using pre-defined dopaminergic cocktails. The dopaminergic efficiencies were evaluated both at gene and protein as well as at secretome levels. RESULTS: The efficiency of DPSCs-CT to differentiate into DAergic-like cells was not equivalent to that of DPSCs. This was further reflected in both gene and protein generation whereby key neuronal markers such as nestin, NURR1 and beta-III-tubulin were expressed significantly lower as compared to differentiated DPSCs (P < 0.05). In addition, expressions of transcriptomes related to neurogenesis revealed downregulation of more than 50% of the genes as compared to differentiated DPSC (P < 0.05). Amongst the notable genes were those from the transcription factors family (FLNA, MEF2C, NEUROG2), signalling pathway family (DLL1, Notch1, TGF-ß1), neuro-inducer family (BDNF) and cell communication family (APBB1). CONCLUSIONS: DPSCs-CT were able to differentiate into DAergic-like cells but not as efficiently as DPSCs. As such, prior to use in regenerative medicine, stem cells from any source should be thoroughly investigated beyond conventional benchmarks such as that proposed by the International Society for Cellular Therapy (ISCT).

Basal expression of growth-factor-associated genes in periodontal ligament stem cells reveals multiple distinctive pathways.

AIM: To identify and compare the expression level of growth-factor-associated genes in human periodontal ligament (PDL) stem cells with dental pulp stem cells isolated from deciduous teeth as well as to assess their suitability in regenerative dentistry. METHODOLOGY: Periodontal ligament and dental pulp stem cells were isolated from deciduous teeth. Human both cells lines were expanded in identical culture condition, and their differentiation profile and cell surface antigen were compared. In addition, growth factor associated genes profiles were assessed using PCR array. RESULTS: Stem cells from deciduous dental pulp (SCD) and periodontal ligament cultures were capable of proliferating and mutually expressed the specific phenotype profile of human mesenchymal stem cells (MSCs). In osteogenic cultures, calcium nodules were observed by day 21 in PDL and dental pulp stem cells. In adipogenic cultures, both cell populations showed positive Oil Red O staining by day 21. Likewise, in chondrogenic cultures, both stem cells expressed the formation of proteoglycan. Interestingly, the expression of growth factor analysis revealed a higher propensity of PDL stem cells towards angiogenesis, osteogenesis and neurogenesis as compared to dental pulp stem cells. CONCLUSIONS: The data suggest the PDL stem cell population can be utilized as potential sources for cell-based therapies in regenerative dentistry.

How far has the pendulum swung in the surgical management of sigmoid volvulus? Experience from the KwaZulu-Natal Teaching Hospitals and review of the literature.

AIM: Sigmoid volvulus is common in sub-Saharan Africa. The aim of the study was to document the clinicopathological patterns of sigmoid volvulus in KwaZulu-Natal. METHOD: Analysis was performed of prospectively collected data of patients presenting with sigmoid volvulus at the KwaZulu-Natal Teaching Hospitals from 2000 to 2009. Data collected included demographics, clinical presentation, operative findings, management and outcome. RESULTS: There were 135 patients (122 male) of mean age 39.3 ± 17 years. Management was by emergency surgery (103), elective surgery (23), no surgery (9). The level of the twist was at the pelvic brim. Fifty-four patients had gangrenous bowel and 81 had viable bowel. Resection was accompanied by primary anastomosis (80) and Hartmann's procedure (46). Complication and mortality rates were 47% and 17% respectively. Mortality rates for emergency and elective surgery were 19% and 9% (P = 0.330), and those for primary anastomosis and Hartmann's procedure were 14% and 24% respectively (P = 0.305). Mortality rates for gangrenous and viable bowel were 21% and 15% respectively (P = 0.624). Twenty-eight (22%) patients required intensive care in the intensive care unit (ICU) with an ICU stay of 8.8 ± 8 days. Hospital stay was 10.5 ± 14.4 days. CONCLUSION: The clinicopathological picture of sigmoid volvulus resembles that in the rest of Africa in that it affects predominantly young African males. The level of the twist is at the pelvic brim. The timing of surgery, the type of anastomosis and the viability of the bowel does not influence outcome.

Antibacterial activity of metabolite produced by Paenibacillus polymyxa strain HKA-15 against Xanthomonas campestris pv. phaseoli.

An antibacterial metabolite extracted from Paenibacillus polymyxa HKA-15 showed strong inhibition against Xanthomonas campestris pv. phaseoli strains CP-1-1 and M-5. Minimum inhibitory concentration (MIC) of crude extract against strains CP-1-1 and M-5 was found to be 1.7 mg/ml and 1.52 mg/ml, respectively. In UV-Vis range, the absorption peak of crude extract was maximum at 240 nm. The compound is resilience to wide range of temperature, pH, surfactants and organic solvents. The complete loss of activity was observed when crude metabolite was treated with pepsin (400 unit/ml). Characterization of crude metabolite suggested its hydrophobic and peptide nature. Inhibition of Xanthomonas campestris pv. phaseoli by peptide like metabolite produced by Paenibacillus polymyxa strain HKA-15 under in vitro conditions showed ecological and biotechnological potential of strain HKA-15 to control common blight disease in beans.

The quest to improve outcomes for abdominal wall incisional hernia repair in Pietermaritzburg: between Scylla and Charybdis.

BACKGROUND: The repair and outcomes of incisional abdominal wall hernias have not yet been benchmarked to allow comparison with recommended best practice in a South African context. This study aimed to address his deficit. METHOD: Patients who underwent an incisional hernia repair between December 2012 and December 2018 were analysed in respect to the following variables: demographics, comorbidities, indication for surgery, site, size, surgical approach, mesh usage, operating times, complications and 30-day mortality. RESULTS: Of the cohort of 224 patients, 185 underwent elective repair. There were 152 open and 72 laparoscopic procedures, and 17 patients (8%) required a repeat operation with an overall in-hospital mortality rate of 6% (13). Eight patients developed an enteric leak. There were nine cardiovascular complications, 24 respiratory complications, 22 surgical site infections and 13 patients developed an acute kidney injury (AKI). There were 39 emergency operations. The emergency cohort were older than the elective with a higher rate of cardiovascular or surgical (CVS) complications and AKI. Eight patients developed an enteric leak. Mortality rates of were significantly higher in the emergency operation cohort compared to the elective group (18% vs 3%). The 13 in-hospital deaths were older, more likely to have undergone an emergency operation, to be diabetic (46% vs 10%), hypertensive (92% vs 33%), have a bowel anastomosis (39% vs 9%), experience an enteric leak (46% vs 1%) and require repeat operation than the patients who survived. CONCLUSION: Incisional abdominal wall hernias are difficult to manage as the patients often have several comorbidities which when coupled with an emergency operation leads to poor outcomes. Improving outcomes requires strategies that address comorbidities and shift the focus to elective rather than emergency repair.

Trimetallic composite nanofibers for antibacterial and photocatalytic dye degradation of mixed dye water.

Membrane technology is an advanced approach to making a healthier and cleaner environment. Using such catalytic membrane technology to get clean, usable water by removal of dye impurities as well as pathogenic microbes is the main goal behind the research work. Here, we present the synthesis and efficacy study of polymethyl methacrylate (PMMA)-based Ag/ZnO/TiO2 trimetallic bifunctional nanofibers with antibacterial and photocatalytic activity. The nanofibers have been proven to be effective for the degradation of methylene blue (MB 93.4%), rhodamine B (Rh 34.6%), auramine-O (Au 65.0%) and fuchsin basic (FB 69.8%) dyes individually within 90 min in daylight. The study is further extended in abating a mixture of these dyes from contaminated water using composite nanofibers. Also, in the case of a mixture of these dyes (3 ppm each), nanofibers show dye degradation efficiency (DDE) of 90.9% (MB), 62.4% (Au) and 90.3% (FB and Rh) in 60 min. The role of Ag nanoparticles with a synergic photocatalytic effect on ZnO and TiO2 is also demonstrated. Also, PMMA/ZnO/TiO2 composite fiber membrane in synergy with silver particles shows better antibacterial activity against Gram-negative bacteria E. coli, making PMMA/Ag/ZnO/TiO2 fibers a promising candidate in water purification.

Biocontrol potential of soybean bacterial endophytes against charcoal rot fungus, Rhizoctonia bataticola.

A total of 137 bacterial isolates from surface sterilized root, stem, and nodule tissues of soybean were screened for their antifungal activity against major phytopathogens like Rhizoctonia bataticola, Macrophomina phaseolina, Fusarium udam, and Sclerotium rolfsii. Nine bacterial endophytes suppressed the pathogens under in vitro plate assay. These were characterized biochemically and identified at the genus level based on their partial sequence analysis of 16S rDNA. Eight of the isolates belonged to Bacillus and one to Paenibacillus. The phylogenetic relationship among the selected isolates was studied and phylogenetic trees were generated. The selected isolates were screened for biocontrol traits like production of hydrogen cyanide (HCN), siderophore, hydrolytic enzymes, antibiotics, and plant growth promoting traits like indole 3-acetic acid production, phosphate solubilization, and nitrogen fixation. A modified assessment scheme was used to select the most efficient biocontrol isolates Paenibacillus sp. HKA-15 (HKA-15) and Bacillus sp. HKA-121 (HKA-121) as potential candidates for charcoal rot biocontrol as well as soybean plant growth promotion.

Automated diagnosis of retinopathy by content-based image retrieval.

PURPOSE: To describe a novel computer-based image analysis method that is being developed to assist and automate the diagnosis of retinal disease. METHODS: Content-based image retrieval is the process of retrieving related images from large database collections using their pictorial content. The content feature list becomes the index for storage, search, and retrieval of related images from a library based upon specific visual characteristics. Low-level analyses use feature description models and higher-level analyses use perceptual organization and spatial relationships, including clinical metadata, to extract semantic information. RESULTS: We defined, extracted, and tested a large number of region- and lesion-based features from a dataset of 395 retinal images. Using a statistical hold-one-out method, independent queries for each image were submitted to the system and a diagnostic prediction was formulated. The diagnostic sensitivity for all stratified levels of age-related macular degeneration ranged from 75% to 100%. Similarly, the sensitivity of detection and accuracy for proliferative diabetic retinopathy ranged from 75% to 91.7% and for nonproliferative diabetic retinopathy, ranged from 75% to 94.7%. The overall purity of the diagnosis (specificity) for all disease states in the dataset was 91.3%. CONCLUSIONS: The probabilistic nature of content-based image retrieval permits us to make statistically relevant predictions regarding the presence, severity, and manifestations of common retinal diseases from digital images in an automated and deterministic manner.

An audit of ingested and aspirated foreign bodies in children at a university hospital in South Africa: The Pietermaritzburg experience.

BACKGROUND: The ingestion or aspiration of foreign bodies (FBs) by children is a common problem around the world. Our centre in Pietermaritzburg, South Africa, has a dedicated paediatric surgical service, and all patients with an ingested or aspirated FB are managed under the direct care of a paediatric surgeon. OBJECTIVES: To review our centre's experience with this problem by means of a retrospective audit and use the data to develop and refine appropriate local management guidelines. METHODS: Grey's Hospital has a hybrid electronic medical registry (HEMR) that captures patient data on admission, after a procedure and on discharge. The HEMR was reviewed and all patients with an appropriate International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10) code indicating an ingested or aspirated FB were identified and retrieved for review. RESULTS: A total of 105 cases of FB ingestion or aspiration in children <12 years of age from January 2012 to December 2014 were identified from the HEMR. The patients' ages ranged from 4 months to 10 years (mean 3 years and 6 months), and 59.0% (n=62) were male and 41.0% (n=43) female. A total of 107 FBs were removed (two patients each had two coins removed). The commonest FBs were coins (n=77, 71.9%), followed by batteries (n=6, 5.6%), plastic toys (n=5, 4.7%), buttons (n=5, 4.7%), screws/washers (n=3, 2.8%), seeds (n=2, 1.9%), needles (n=2, 1.9%), bones (n=2, 1.9%), a marble (n=1, 0.9%), a rubber eraser (n=1, 0.9%), a curtain hook (n=1, 0.9%), a nail (n=1, 0.9%) and a wood speck (n=1, 0.9%). Of the FBs, 67 (62.6%) were in the oesophagus, 17 (15.9%) in the respiratory system, 14 (13%) in the intestine and 9 (8.4%) in the oral cavity. The average time from ingestion/aspiration to presentation was <48 hours. Of the FBs, 67 (62.6%) were removed via rigid oesophagoscopy and 13 (12.1%) via rigid bronchoscopy, 13 (12.1%) were passed rectally, and 9 (8.4%) were removed via grasping forceps in the oral cavity, 4 (3.7%) via thoracotomy and 1 (0.9%) via emergency laparotomy. A total of 15 complications included mucosal ulceration/slough (n=6, 40.0%), oesophageal perforation (n=3, 20.0%), aspiration pneumonia (n=3, 20.0%), and tracheal perforation, lung collapse and contact bleed (n=1 each, 6.7%). No patient presented in respiratory distress or needed emergency airway management, and there were no deaths. CONCLUSIONS: The development of a dedicated paediatric surgery service and the implementation of management protocols have resulted in excellent outcomes for this problem.

Homology model of a novel thermostable xylanase from Bacillus subtilis-AK1.

Xylanases are glycosyl hydrolases that catalyze the hydrolysis of internal beta-1,4 glycosidic bonds of xylan, the major hemi-cellulose component of the plant cell wall. Enzymes such as xylanases are used considerably in industries. Their industrial usage is especially attractive since they can replace some of the environmental pollutants. We have earlier isolated a family 11-xylanase gene from Bacillus subtilis-AK1, which is active at high temperature as well as at alkaline pH. In order to understand the factors liable for the adaptation of this enzyme, three dimensional model of B. subtilis-AK1 xylanase has now been obtained by homology modeling. Modeling was carried out using Molecular Operating Environment (MOE) software developed by Chemical Computing Group Inc., running on Pentium IV workstation. The model showed that B. subtilis-AK1 xylanase having molecular weight around 20 kDa contains in its fold an alpha-helix and two beta-sheets packed against each other forming a beta-sandwich. The conserved active site amino acids E78R, Y80L were mutated in this novel B. subtilis-AK1 strain, but the protein folding and the function was maintained with high thermal stability. Several minor modifications appeared to be responsible for the increased thermo stability of AK1. Docking studies of the substrate xylan with -AK1 shows the possibility of the Arg 78 acting as the nucleophile instead of Glu 78.

Detection of anatomic structures in human retinal imagery.

The widespread availability of electronic imaging devices throughout the medical community is leading to a growing body of research on image processing and analysis to diagnose retinal disease such as diabetic retinopathy (DR). Productive computer-based screening of large, at-risk populations at low cost requires robust, automated image analysis. In this paper we present results for the automatic detection of the optic nerve and localization of the macula using digital red-free fundus photography. Our method relies on the accurate segmentation of the vasculature of the retina followed by the determination of spatial features describing the density, average thickness, and average orientation of the vasculature in relation to the position of the optic nerve. Localization of the macula follows using knowledge of the optic nerve location to detect the horizontal raphe of the retina using a geometric model of the vasculature. We report 90.4% detection performance for the optic nerve and 92.5% localization performance for the macula for red-free fundus images representing a population of 345 images corresponding to 269 patients with 18 different pathologies associated with DR and other common retinal diseases such as age-related macular degeneration.

Harmony search method: theory and applications.

The Harmony Search (HS) method is an emerging metaheuristic optimization algorithm, which has been employed to cope with numerous challenging tasks during the past decade. In this paper, the essential theory and applications of the HS algorithm are first described and reviewed. Several typical variants of the original HS are next briefly explained. As an example of case study, a modified HS method inspired by the idea of Pareto-dominance-based ranking is also presented. It is further applied to handle a practical wind generator optimal design problem.

Differentiation of dental pulp stem cells into islet-like aggregates.

The post-natal dental pulp tissue contains a population of multipotent mesenchymal progenitor cells known as dental pulp stromal/stem cells (DPSCs), with high proliferative potential for self-renewal. In this investigation, we explored the potential of DPSCs to differentiate into pancreatic cell lineage resembling islet-like cell aggregates (ICAs). We isolated, propagated, and characterized DPSCs and demonstrated that these could be differentiated into adipogenic, chondrogenic, and osteogenic lineage upon exposure to an appropriate cocktail of differentiating agents. Using a three-step protocol reported previously by our group, we succeeded in obtaining ICAs from DPSCs. The identity of ICAs was confirmed as islets by dithiozone-positive staining, as well as by expression of C-peptide, Pdx-1, Pax4, Pax6, Ngn3, and Isl-1. There were several-fold up-regulations of these transcription factors proportional to days of differentiation as compared with undifferentiated DPSCs. Day 10 ICAs released insulin and C-peptide in a glucose-dependent manner, exhibiting in vitro functionality. Our results demonstrated for the first time that DPSCs could be differentiated into pancreatic cell lineage and offer an unconventional and non-controversial source of human tissue that could be used for autologous stem cell therapy in diabetes.

Retina lesion and microaneurysm segmentation using morphological reconstruction methods with ground-truth data.

In this work we report on a method for lesion segmentation based on the morphological reconstruction methods of Sbeh et. al. We adapt the method to include segmentation of dark lesions with a given vasculature segmentation. The segmentation is performed at a variety of scales determined using ground-truth data. Since the method tends to over-segment imagery, ground-truth data was used to create post-processing filters to separate nuisance blobs from true lesions. A sensitivity and specificity of 90% of classification of blobs into nuisance and actual lesion was achieved on two data sets of 86 images and 1296 images.

Using a patient image archive to diagnose retinopathy.

Diabetes has become an epidemic that is expected to impact 365 million people worldwide by 2025. Consequently, diabetic retinopathy is the leading cause of blindness in the industrialized world today. If detected early, treatments can preserve vision and significantly reduce debilitating blindness. Through this research we are developing and testing a method for automating the diagnosis of retinopathy in a screening environment using a patient archive and digital fundus imagery. We present an overview of our content-based image retrieval (CBIR) approach and provide performance results for a dataset of 98 images from a study in Canada when compared to an archive of 1,355 patients from a study in the Netherlands. An aggregate performance of 89% correct diagnosis is achieved, demonstrating the potential of automated, web-based diagnosis for a broad range of imagery collected under different conditions and with different cameras.