Prevalence of HIV ocular manifestations in relation to CD4 count at ART Centre, SMCH, Chennai

INTRODUCTION: HIV;bane of new era has been a serious health issue since its discovery in the early 70’s. Although with the current fall in the incidence globally and India; as per UN 2012 reports ;India is still the third largest nation with HIV population. HIV manifests indirectly and it does so by decreasing the immunity especially CD4 cells,thereby leading to secondary infections. It affects all systems alike ;eye and its adnexa is no exception. HIV ocular complications include minor opportunistic infection,tumor, inflammation, vasculopathy and retinopathy. It is important that these manifestations are detected irrespective of symptoms or history and treated at the earliest possible. This study is done in order to find the prevalence of the various ocular manifestation of HIV, its correlation to CD4 count and the role of HAART. AIM: To evaluate the prevalence of ocular manifestations in HIV seropositive patients, attending the ART centre, Stanley Medical College and Hospital. To evaluate how the manifestations correlate to the CD4 count. To evaluate the impact of HAART on ocular HIV manifestations. METHODS AND MATERIALS: STUDY DESIGN: Cross sectional study was undertaken on 100 HIV seropositive patient attending the ART centre with known CD4 count was included in the study.The study period was from February 2013 till completion of hundred patients. INCLUSION CRITERIA HIV seropositve consented patients attending ART centre irrespective of ocular complaints, irrespective of treatment status. Any age group CD4 count obtained at the time of examination. EXCLUSION CRITERIA Severely ill patients. CD4 count could not be obtained. Pre-existing systemic illnesses. The importance of ocular examination in them was thoroughly explained in patients own language.Consent in patients own language was obtained from all those who were willing to take part in study.Any photographic records of the lesions were taken only if the patient consented for the same.Upon completion of data collection, statistical analysis was applied. STATISTICAL ANALYSIS: Chi square test was done for statistical analysis of the obtained data. ROUTINE OCULAR EXAMINATION WAS DONE AS FOLLOWS: • Ocular history. • Ocular examination included: • Best corrected visual acuity. ( Snellen’s chart ) • Slit lamp evaluation – Adnexa and Anterior segment • Dilated fundus evaluation (0.8 % tropicamide with 5% phenylephirine) – 90 D and 20 D • Neuro ophthalmological examination • Orbit • Tonometry for IOP evaluation • Schirmer’s for dry eye evaluation • Patient with suspected lesions were referred for complete systemic and laboratory work up. • Serological investigations included TORCH titre, PCR assay for HZV, VZ. • Other investigations were done as per clinical indication included CT brain/ MRI brain. OBSERVATION AND DISCUSSION: The mean age of patients in our study was 38.14 +/- 11.84 which fell in line with mean age of the comparative studies.Majority of the patient prevalence in our study fell under the reproductive age group of 20-40 years. This pattern was similarly noticed in Biswas et al , Gururaj et al and Lamichhane G et al study. However our prevalence rate of 58 % was closely comparable to the Gururaj et al study which had 54 %.Also comparable with the Gururaj et al study was the decrease in prevalence with increase in age.Of special mention is the similarity in the prevalence of patients in the age group < 20 years. Our study shows a higher male prevalence in comparison to females. The age gender distribution in our study was not significant, p= 0.3. This was also the finding in Lamichhane G et all study. Sexual route was the most common mode of disease transmission, and this was observed in study by Biswas et al and Gururaj et al. Gururaj et al had 1 homosexual route of exposure.P value of 0.1274 signifies that the route of exposure has no impact the prevalence of the ocular manifestations.Majority of the patients in our study were observed in clinical stage I and II. The findings were similar in the Gururaj et al and Amare et al study. It was observed in our study that all patients those who fell under the Clinical category III /IV had ocular HIV manifestation, and mostly of the opportunistic type. This was equally observed in the studies to which we compared to in the above table.With p value of 0.003 we can conclude that prevalence of ocular manifestation increases with the clinical staging of disease. And this is probably due to the increase in the opportunistic infection in these stages. This was observed both in Gururaj et al and the Amare et al study as well.We observed an increased prevalence of ocular manifestations in the CD4 range of 200 – 500 cells/mm3. This was comparable to the Ethiopian study by Amare et al.P value in our study was 0.0235, which was significant. This significance was observed in all the above mentioned studies.Hence ocular manifestations is seen to increase significantly with decrease in CD4 count, especially in levels < 200 cells/mm3. Blepharitis and conjunctival microvasculopathy was the commonest anterior segment findings observed in this study. The prevalence of both of which were significantly higher in comparison to the studies mentioned above.Kaposi sarcoma and conjunctival squamous cell carcinoma were nil, and were comparable to the two Indian studies mentioned above. These findings were present in the African studies. And this has been implicated due to the homosexual practises.we see differences in most of the anterior segment presentations in comparison to other Indian studies. This can be attributed to the geographical change in location of the study.The prevalence of HIV retinopathy, toxoplasmosis acute retinal necrosis and uveitis in our study was comparable to the prevalence in Biswas et al study.The same finding was not so with CMV retinitis. This limitation was observed probably due to the sample size in our study. Ocular TB and syphilis were not recorded in our study. CONCLUSION: HIV infection is a problematic communicable disease present in our population, affecting commonly the reproductive age group. HIV manifests in the eye either directly in the form of viral load or causes low immunity thereby increasing chances for opportunistic infections.With the introduction of HAART, the life expectancy of the patients have significantly increased. However the ocular manifestations continue to present in innumerable forms.Not all patients with early HIV opportunistic infection present to us with ocular symptoms until unless the manifestation is severely blinding and irreversible.Most of the symptomatic patients are the ones with blepharitis and conjunctivitis, a non-blinding yet troublesome form of disease manifestations.The ART centres in India at present practice just the referral of patients for ophthalmological examination only when the patient develops ocular complaints.With the number of ocular findings observed, our study highlights the need for a routine ophthalmological screening of all HIV seropositive patients. We recommend a routine screening of HIV seropositive patients upon diagnosis, prior to starting ART therapy to obtain a baseline ocular status. Once the patient is started on HAART , he/she must undergo at-least a half yearly ocular examination. This is important for two reasons; one to look out for immune reconstitution syndromes, two to identify the ocular side effects of HAART.CD4 counts have to be strictly considered while monitoring these patients. It serves both as a risk factor as well as an indicator of opportunistic manifestations.A very important observation we made was the patients non-consenting to any detailed examination outside of the ART centre. This was due to the stigma attached to the disease and the fear of being publically recognised as HIV seropositive.All this indicates a need for provision of ophthalmic setup in the ART centre.This can be made possible with adequate resources and trained ophthalmic personnel

Accurate Single Image Multi-Modal Camera Pose Estimation

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Progressive Structure from Motion

Structure from Motion or the sparse 3D reconstruction out of individual photos is a long studied topic in computer vision. Yet none of the existing reconstruction pipelines fully addresses a progressive scenario where images are only getting available during the reconstruction process and intermediate results are delivered to the user. Incremental pipelines are capable of growing a 3D model but often get stuck in local minima due to wrong (binding) decisions taken based on incomplete information. Global pipelines on the other hand need the access to the complete viewgraph and are not capable of delivering intermediate results. In this paper we propose a new reconstruction pipeline working in a progressive manner rather than in a batch processing scheme. The pipeline is able to recover from failed reconstructions in early stages, avoids to take binding decisions, delivers a progressive output and yet maintains the capabilities of existing pipelines. We demonstrate and evaluate our method on diverse challenging public and dedicated datasets including those with highly symmetric structures and compare to the state of the art.Comment: Accepted to ECCV 201

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Fibulin-3 is necessary to prevent cardiac rupture following myocardial infarction

Published online: 11 September 2023Despite the high prevalence of heart failure in the western world, there are few effective treatments. Fibulin-3 is a protein involved in extracellular matrix (ECM) structural integrity, however its role in the heart is unknown. We have demonstrated, using single cell RNA-seq, that fibulin-3 was highly expressed in quiescent murine cardiac fibroblasts, with expression highest prior to injury and late post-infarct (from ~ day-28 to week-8). In humans, fibulin-3 was upregulated in left ventricular tissue and plasma of heart failure patients. Fibulin-3 knockout (Efemp1-/-) and wildtype mice were subjected to experimental myocardial infarction. Fibulin-3 deletion resulted in significantly higher rate of cardiac rupture days 3-6 post-infarct, indicating a weak and poorly formed scar, with severe ventricular remodelling in surviving mice at day-28 post-infarct. Fibulin-3 knockout mice demonstrated less collagen deposition at day-3 post-infarct, with abnormal collagen fibre-alignment. RNA-seq on day-3 infarct tissue revealed upregulation of ECM degradation and inflammatory genes, but downregulation of ECM assembly/structure/organisation genes in fibulin-3 knockout mice. GSEA pathway analysis showed enrichment of inflammatory pathways and a depletion of ECM organisation pathways. Fibulin-3 originates from cardiac fibroblasts, is upregulated in human heart failure, and is necessary for correct ECM organisation/structural integrity of fibrotic tissue to prevent cardiac rupture post-infarct.Lucy A. Murtha, Sean A. Hardy, Nishani S. Mabotuwana, Mark J. Bigland, Taleah Bailey, Kalyan Raguram, Saifei Liu, Doan T. Ngo, Aaron L. Sverdlov, Tamara Tomin, Ruth Birner, Gruenberger, Robert D. Hume, Siiri E. Iismaa, David T. Humphreys, Ralph Patrick, James J. H. Chong, Randall J. Lee, Richard P. Harvey, Robert M. Graham, Peter P. Rainer and Andrew J. Boyl

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We propose a new approach for combining deep-learned non-metric monocular depth with affine correspondences (ACs) to estimate the relative pose of two calibrated cameras from a single correspondence. Considering the depth information and affine features, two new constraints on the camera pose are derived. The proposed solver is usable within 1-point RANSAC approaches. Thus, the processing time of the robust estimation is linear in the number of correspondences and, therefore, orders of magnitude faster than by using traditional approaches. The proposed 1AC+D solver is tested both on synthetic data and on 110395 publicly available real image pairs where we used an off-the-shelf monocular depth network to provide up-to-scale depth per pixel. The proposed 1AC+D leads to similar accuracy as traditional approaches while being significantly faster. When solving large-scale problems, e.g., pose-graph initialization for Structure-from-Motion (SfM) pipelines, the overhead of obtaining ACs and monocular depth is negligible compared to the speed-up gained in the pairwise geometric verification, i.e., relative pose estimation. This is demonstrated on scenes from the 1DSfM dataset using a state-of-the-art global SfM algorithm. Source code: https://github.com/eivan/one-ac-pos

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