Publications by authors named "Shanmuganathan V"

This paper addresses the pressing issue of diabetes, which is a widespread condition affecting a huge population worldwide. As cells become less responsive to insulin or fail to produce it adequately, blood sugar levels rise. This has the potential to cause severe health complications including kidney disease, vision impairment and heart conditions.

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DdmDE is a novel plasmid defense system that was discovered in the seventh pandemic Vibrio cholerae strain of the biotype O1 EI Tor. In this issue of Cell, Yang and coworkers reveal the mechanisms underlying the assembly and activation of the DdmDE defense system.

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Despite being treatable and preventable, tuberculosis (TB) affected one-fourth of the world population in 2019, and it took the lives of 1.4 million people in 2019. It affected 1.

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The recent outbreak of a novel coronavirus, named COVID-19 by the World Health Organization (WHO) has pushed the global economy and humanity into a disaster. In their attempt to control this pandemic, the governments of all the countries have imposed a nationwide lockdown. Although the lockdown may have assisted in limiting the spread of the disease, it has brutally affected the country, unsettling complete value-chains of most important industries.

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A proper method on real-time monitoring of organic biomass degradation and its evaluation for safeguarding the ecosystem is the need of the hour. The work process designed in this study is to demarcate the anaerobic digestion potential using kinetic modelling and web GIS application methods. Wastewater source that causes pollution are identified through satellite maps such as solid earth, drain system, surface of earth structure, land filling and land use.

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The objective of this work was to study the effect of transition metal ion doping (1 wt% of Mn, Fe, Co, Ni, and Cu) in indium oxide (InO) on its photocatalytic activity to degrade organic dyes, which are considered potential environment pollutants. The transition metal ion-doped InO nanocube photocatalyst was prepared the hydrothermal method. After understanding the thermal behavior of the as-prepared sample (In(OH)), it was calcined at 400 °C for 3 h to obtain InO.

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XBP1u, a central component of the unfolded protein response (UPR), is a mammalian protein containing a functionally critical translational arrest peptide (AP). Here, we present a 3 Å cryo-EM structure of the stalled human XBP1u AP. It forms a unique turn in the ribosomal exit tunnel proximal to the peptidyl transferase center where it causes a subtle distortion, thereby explaining the temporary translational arrest induced by XBP1u.

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Co-translational protein targeting to membranes depends on the regulated interaction of two ribonucleoprotein particles (RNPs): the ribosome and the signal recognition particle (SRP). Human SRP is composed of an SRP RNA and six proteins with the SRP GTPase SRP54 forming the targeting complex with the heterodimeric SRP receptor (SRαβ) at the endoplasmic reticulum membrane. While detailed structural and functional data are available especially for the bacterial homologs, the analysis of human SRP was impeded by the unavailability of recombinant SRP.

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Ski2-Ski3-Ski8 (Ski) is a helicase complex functioning with the RNA-degrading exosome to mediate the 3'-5' messenger RNA (mRNA) decay in turnover and quality-control pathways. We report that the Ski complex directly associates with 80S ribosomes presenting a short mRNA 3' overhang. We determined the structure of an endogenous ribosome-Ski complex using cryo-electron microscopy (EM) with a local resolution of the Ski complex ranging from 4 angstroms (Å) in the core to about 10 Å for intrinsically flexible regions.

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During protein synthesis, ribosomes become stalled on polyproline-containing sequences, unless they are rescued in archaea and eukaryotes by the initiation factor 5A (a/eIF-5A) and in bacteria by the homologous protein EF-P. While a structure of EF-P bound to the 70S ribosome exists, structural insight into eIF-5A on the 80S ribosome has been lacking. Here we present a cryo-electron microscopy reconstruction of eIF-5A bound to the yeast 80S ribosome at 3.

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Background: A key goal for HIV-1 envelope immunogen design is the induction of cross-reactive neutralizing antibodies (nAbs). As AIDS vaccine recipients will not be exposed to strains exactly matching any immunogens due to multiple HIV-1 quasispecies circulating in the human population worldwide, heterologous SHIV challenges are essential for realistic vaccine efficacy testing in primates. We assessed whether polyclonal IgG, isolated from rhesus monkeys (RMs) with high-titer nAbs (termed SHIVIG), could protect RMs against the R5-tropic tier-2 SHIV-2873Nip, which was heterologous to the viruses or HIV-1 envelopes that had elicited SHIVIG.

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Existing technologies allow isolating antigen-specific monoclonal antibodies (mAbs) from B cells. We devised a direct approach to isolate mAbs with predetermined conformational epitope specificity, using epitope mimetics (mimotopes) that reflect the three-dimensional structure of given antigen subdomains. We performed differential biopanning using bacteriophages encoding random peptide libraries and polyclonal antibodies (Abs) that had been affinity-purified with either native or denatured antigen.

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Purpose. To report the use of femtosecond laser-assisted in situ keratomileusis (LASIK) in the treatment of hyperopia subsequent to Descemet stripping-automated endothelial keratoplasty (DSAEK). Methods.

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Background: The high prevalence of HIV-1/AIDS in areas endemic for schistosomiasis and other helminthic infections has led to the hypothesis that parasites increase host susceptibility to immunodeficiency virus infection. We previously showed that rhesus macaques (RM) with active schistosomiasis were significantly more likely to become systemically infected after intrarectal (i.r.

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Aims: Cognitive factors (eg, academic achievement) have had a significant role in selecting postgraduate surgical trainees in the past. This project sought to determine the role of a national undergraduate ophthalmology prize examination (Duke-Elder examination) in the selection of postgraduate ophthalmology trainees. This would also serve as a quality assurance exercise for the assessment, in which the ultimate aim is to encourage trainees into ophthalmology.

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Background: The Limbal epithelial crypt (LEC) is a solid cord of cells, approximately 120 microns long. It arises from the undersurface of interpalisade rete ridges of the limbal palisades of Vogt and extends deeper into the limbal stroma parallel or perpendicular to the palisade. There are up to 6 or 7 such LEC, variably distributed along the limbus in each human eye.

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Introduction: Amniotic membrane (AM) has gained increasing popularity as a useful carrier for ex vivo-expanded cells for tissue engineering, particularly in ocular surface reconstruction. However, current methods employed for denuding AM are highly variable, and the consequent effects on the structural and molecular composition of the AM basement membrane (BM) are ambiguous. We compare the effects of the main denuding procedures, and propose a highly effective standardized alternative.

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Aims: To describe the long-term risk of bullous keratopathy following argon laser iridotomy (ALI) in Japan and to compare it with other centres in the world.

Methods: We retrospectively reviewed the case records of all patients with ALI-induced bullous keratopathy that underwent penetrating keratoplasty at Kyoto Prefectural University of Medicine (KPUM) from January 2001 to December 2004. The results were compared with the other representative centres in Singapore and the UK.

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Background: The amniotic membrane is a useful tool in the management of several ocular surface diseases. Despite numerous studies, standardization of the use of the membrane and of outcome measures is lacking. Herein, the authors' results of amniotic membrane transplantation (AMT) in ocular surface reconstruction against defined outcome measures are reported.

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Aim: In 2005 we reported the discovery of a novel anatomical structure at the limbus, which we termed the limbal epithelial crypt (LEC). The purpose of this study was to further evaluate the distribution, immunophenotypical, and ultra structural characteristics of the LEC as a putative niche of stem cells.

Methods: Sequential histological sections of human corneo-scleral limbal rims were examined for the presence and distribution of the LEC.

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Background: Unlike the immune privilege enjoyed by low-risk corneal grafts, high-risk corneal grafts experience rejection rates comparable to liver and kidney transplants. Systemic immunosuppression reduces the risk of rejection in high-risk corneal grafts.

Methods: Systemic tacrolimus, a specific T cell inhibitor, was used at a mean daily dose of 2.

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Amniotic membrane is commonly exploited in several surgical procedures. Despite a freeze preservation period, it is reported to retain wound healing, anti-angiogenic, antiinflammatory and anti-scarring properties; however, little is known about the active protein content. 2-DE analysis of transplant-ready amniotic membrane (TRAM) was performed.

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Aims: To determine the epithelial proliferative capacity of organ cultured limbal tissue and correlate this with various donor and eye banking factors.

Methods: 24 corneoscleral limbal (CSL) rims left over from penetrating keratoplasty were split in half and set up as in vitro explant cultures. Corneal epithelial proliferative potential (CEPP) was assessed by the number of "cycles" of growth achieved before explants underwent exhaustion and failure to generate an epithelium to subconfluence.

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