Determination of Cup to Disc Ratio Using Unsupervised Machine Learning Techniques for Glaucoma Detection

The cup nerve head, optic cup, optic disc ratio and neural rim configuration are observed as important for detecting glaucoma at an early stage in clinical practice. The main clinical indicator of glaucoma optic cup to disc ratio is currently determined manually by limiting the mass screening was potential. This paper proposes the following methods for an automatic cup to disc ratio determination. In the first part of the work, fundus image of the optic disc region is considered. Clustering means K is used automatically to extract the optic disc whereas K-value is automatically selected by algorithm called hill climbing. The segmented contour of optic cup has been smoothened by two methods namely elliptical fitting and morphological fitting. Cup to disc ratio is calculated for 50 normal images and 50 fundus images of glaucoma patients. Throughout this paper, the same set of images has been used and for these images, the cup to disc ratio values are provided by ophthalmologist which is taken as the gold standard value. The error is calculated with reference to this gold standard value throughout the paper for cup to disc ratio comparison. The mean error of the K-means clustering method for elliptical and morphological fitting is 4.5% and 4.1%, respectively. Since the error is high, fuzzy C-mean clustering has been chosen and the mean error of the method for elliptical and morphological fitting is 3.83% and 3.52%. The error can further be minimized by considering the inter pixel relation. To achieve another algorithm is by Spatially Weighted fuzzy C-means Clustering (SWFCM) is used. The optic disc and optic cup have clustered and segmented by SWFCM Clustering. The SWFCM mean error clustering method for elliptical and morphological fitting is 3.06% and 1.67%, respectively. In this work fundus images were collected from Aravind eye Hospital, Pondicherry.     

Comparative transcriptome analysis of wing discs from Bombyx mori and Bombyx mandarina

The insect wing is developed from the wing imaginal disc which is designed from the embryonic ectoderm. To get insight into gene expression profiles in wing discs of Bombyx mori during metamorphosis, we compared the gene expression in the wing between B. mori and B. mandarina moth through RNA-seq. Out of total valid reads identified from the 5th day of 5th instar larvae of silkworm (L5), 7th day of pupae (P7), 1st day of moth (M1) and 1st day of wild silkworm moth (WM1), 20,092,004, 29,251,647, 24,654,695 and 19,753,089 reads were mapped to the mRNA reference sequences of silkworm, respectively. 9229, 7048, 9268 and 6701 differentially expressed genes (DEGs) were respectively recorded in P7 vs L5, M1 vs P7, M1 vs L5 and WM1 vs M1. Further, the peroxisome, ribosome, endocytosis and oxidative phosphorylation pathways were significantly regulated in the metamorphosis of the silkworm. Our study identified 16 orthologous genes with a positive selection from M1, which might be subjected to artificial selection in the domestication of B. mori and would play vital roles in the flight of B. mandarina.     

Therapeutic potential of melatonin in the intervertebral disc degeneration through inhibiting the ferroptosis of nucleus pulpous cells

Ferroptosis, a novel type of cell death mediated by the iron-dependent lipid peroxidation, contributes to the pathogenesis of the intervertebral disc degeneration (IDD). Increasing evidence demonstrated that melatonin (MLT) displayed the therapeutic potential to prevent the development of IDD. Current mechanistic study aims to explore whether the downregulation of ferroptosis contributes to the therapeutic capability of MLT in IDD. Current studies demonstrated that conditioned medium (CM) from the lipopolysaccharide (LPS)-stimulated macrophages caused a series of changes about IDD, including increased intracellular oxidative stress (increased reactive oxygen species and malondialdehyde levels, but decreased glutathione levels), upregulated expression of inflammation-associated factors (IL-1β, COX-2 and iNOS), increased expression of key matrix catabolic molecules (MMP-13, ADAMTS4 and ADAMTS5), reduced the expression of major matrix anabolic molecules (COL2A1 and ACAN), and increased ferroptosis (downregulated GPX4 and SLC7A11 levels, but upregulated ACSL4 and LPCAT3 levels) in nucleus pulposus (NP) cells. MLT could alleviate CM-induced NP cell injury in a dose-dependent manner. Moreover, the data substantiated that intercellular iron overload was involved in CM-induced ferroptosis in NP cells, and MLT treatment alleviated intercellular iron overload and protected NP cells against ferroptosis, and those protective effects of MLT in NP cells further attenuated with erastin and enhanced with ferrostatin-1(Fer-1). This study demonstrated that CM from the LPS-stimulated RAW264.7 macrophages promoted the NP cell injury. MLT alleviated the CM-induced NP cell injury partly through inhibiting ferroptosis. The findings support the role of ferroptosis in the pathogenesis of IDD, and suggest that MLT may serve as a potential therapeutic approach for clinical treatment of IDD.     

Leaf Disc Inoculation, a Fast and Precise Test for the Screening of Metalaxyl Tolerance in Sunflower Downy Mildew

A new method, based on leaf disc inoculation, was developed for the screening of metalaxyl tolerance in field isolates of Plasmopara halstedii . High-pressure liquid chromatography (HPLC) was used to determine the fungicide concentration in the inoculation medium and in the incubated leaf tissue over the test period. These measurements revealed that the fungicide concentration inside the leaf tissue within 24 h had adjusted to the concentration in the outer medium and remained constant for the time of cultivation over a period of more than 11 days. In contrast to whole seedling tests with application of the fungicide via seed dressing, the leaf disc method allows precise quantification of the effective fungicide concentration at the site of infection and is less space and time consuming. Metalaxyl tolerance of P. halstedii isolates was gradually determined according to the sporulation of the pathogen on sunflower leaf discs in the presence of increasing fungicide concentrations. Isolates collected in South Germany showed no tolerance and sporulation was prohibited when tests were carried out at 0.02  μ g (a.i.)/ml of metalaxyl or more. In contrast, a tolerant French isolate developed sporangia on leaf discs incubated in a metalaxyl solution of 100  μ g (a.i.)/ml.     

Electrophoretic separation of protein pattern in different tissues of four marine penaeid prawns in relation to sex

The protein patterns of gill, midgut gland and abdominal muscle tissues of four different marine penaeid prawn species: Metapenaeus affinis, Metapenaeus monoceros, Parapenaeopsis hardwickii and Parapenaeopsis stylifera were investigated qualitatively by polyacrylamid gel disc electrophoresis in relation to sex. All tissues showed their own peculiar pattern of protein fractions. The possible significance of these differences is discussed.This investigation was supported by I.C.A.R., New Delhi, through a project on Reprod. Endocr. Edible prawns     

Upregulation of P53 promotes nucleus pulposus cell apoptosis in intervertebral disc degeneration through upregulating NDRG2

P53 is an apoptosis marker which is involved in determining nucleus pulposus (NP) cell fate. Little is known about P53 interaction with N-Myc downstream-regulated gene 2 (NDRG2) in intervertebral disc degeneration (IVDD). Here, we studied the role of the P53-NDRG2 axis in IVDD. We found that NDRG2 was expressed in NP tissue obtained from patients with IVDD. The level of NDRG2 was positively related to the severity of IVDD, as determined by Pfirrmann grading. Subsequently, we overexpressed NDRG2 in human NP cells by adenoviral transfection and studied the effects of increased levels of NDRG2 on the viability and apoptosis of these cells. NDRG2 overexpression induced NP cell apoptosis and reduced viability in NP cells obtained from patient with IVDD. We also found that the level of P53 was elevated in NP cells from patients with IVDD and treatment with exogenous P53 upregulated NDRG2 in NP cells. Last, IVDD model was established in P53 knockout mice and the pathological changes in the intervertebral discs and NDRG2 expression were examined. P53 knockout can reduce the damage of NP tissues after IVDD surgery to some extent. Restoration of NDRG2 antagonized the effect of P53 knockout on IVDD. Collectively, this study suggests that elevated P53 in NP cells stimulates apoptosis of the cells by upregulating NDRG2 expression, thereby exacerbating IVDD.     

Tumor necrosis factor alpha promotes the proliferation of human nucleus pulposus cells via nuclear factor-κB,c-Jun N-terminal kinase,and p38 mitogen-activated protein kinase

Although tumor necrosis factor alpha (TNF-α) is known to play a critical role in intervertebral disc (IVD) degeneration, the effect of TNF-α on nucleus pulposus (NP) cells has not yet been elucidated. The aim of this study was to explore the effect of TNF-α on proliferation of human NP cells. NP cells were treated with different concentrations of TNF-α. Cell proliferation was determined by cell counting kit-8 (CCK-8) analysis and Ki67 immunofluorescence staining, and expression of cyclin B1 was studied by quantitative real-time RT-PCR. Cell cycle was measured by flow cytometry and cell apoptosis was analyzed using an Annexin V–fluorescein isothiocyanate (FITC) & propidium iodide (PI) apoptosis detection kit. To identify the mechanism by which TNF-α induced proliferation of NP cells, selective inhibitors of major signaling pathways were used and Western blotting was carried out. Treatment with TNF-α increased cell viability (as determined by CCK-8 analysis) and expression of cyclin B1 and the number of Ki67-positive and S-phase NP cells, indicating enhancement of proliferation. Consistent with this, NP cell apoptosis was suppressed by TNF-α treatment. Moreover, inhibition of NF-κB, c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) blocked TNF-α-stimulated proliferation of NP cells. In conclusion, the current findings suggest that the effect of TNF-α on IVD degeneration involves promotion of the proliferation of human NP cells via the NF-κB, JNK, and p38 MAPK pathways.     

Role and molecular mechanism of ghrelin in degenerative musculoskeletal disorders

Ghrelin is a brain-gut peptide, and the first 28-peptide that was found in the gastric mucosa. It has a growth hormone (GH)-releasing hormone-like effect and can potently promote the release of GH from pituitary GH cells; however, it is unable to stimulate GH synthesis. Therefore, ghrelin is believed to play a role in promoting bone growth and development. The correlation between ghrelin and some degenerative diseases of the musculoskeletal system has been reported recently, and ghrelin may be one of the factors influencing degenerative pathologies, such as osteoporosis, osteoarthritis, sarcopenia and intervertebral disc degeneration. With population ageing, the risk of health problems caused by degenerative diseases of the musculoskeletal system gradually increases. In this article, the roles of ghrelin in musculoskeletal disorders are summarized to reveal the potential effects of ghrelin as a key target in the treatment of related bone and muscle diseases and the need for further research.