Distinct Structural Elements Govern the Folding, Stability, and Catalysis in the Outer Membrane Enzyme PagP.

The outer membrane enzyme PagP is indispensable for lipid A palmitoylation in Gram-negative bacteria and has been implicated in resistance to host immune defenses. PagP possesses an unusual structure for an integral membrane protein, with a highly dynamic barrel domain that is tilted with respect to the membrane normal. In addition, it contains an N-terminal amphipathic helix.

Comparison of maternal and fetal outcomes among Asian Indian pregnant women with or without gestational diabetes mellitus: A situational analysis study (WINGS-3).

Aim: To compare the existing maternal and fetal outcomes in Asian Indian women with or without gestational diabetes mellitus (GDM) before the development of the Women in India with GDM Strategy (WINGS) GDM model of care (MOC).

Materials And Methods: Records of pregnant women were extracted retrospectively from three maternity centers in Chennai. GDM was diagnosed using the International Association for Pregnancy Study Groups criteria or the Carpenter and Coustan criteria.

Glucose tolerance status of Asian Indian women with gestational diabetes at 6weeks to 1year postpartum (WINGS-7).

Aim: To determine postpartum glucose tolerance status among women with gestational diabetes mellitus (GDM) recruited under the Women In India with GDM Strategy (WINGS) Model of Care (MOC).

Methods: Through the WINGS MOC programme, 212 women with GDM were followed till delivery between November 2013 and August 2015. All women were advised to return for a postpartum oral glucose tolerance test (OGTT) 6-12weeks after delivery.

Physical activity patterns and gestational diabetes outcomes - The wings project.

Objective: To compare physical activity (PA) patterns in pregnant woman with and without gestational diabetes (GDM) and to assess the effects of an exercise intervention on change in PA patterns, blood glucose levels and pregnancy outcomes in GDM women.

Methods: For the first objective, PA patterns were studied in 795 pregnant women with and without GDM. For the second objective, the Women in India with Gestational Diabetes Strategy-Model of Care (WINGS-MOC) intervention were evaluated in 151 women out of 189 with GDM.

Solvation driven conformational transitions in the second transmembrane domain of mycobacteriophage holin.

Holins are pore-forming membrane proteins synthesized by lytic phages. The second transmembrane domain (TM2) of Mycobacteriophage D29 holin presents an Ala- and Gly-rich sequence, with a currently unknown structure and function. In this study, we present the spectroscopic characterization of synthetic TM2 in various solvents, detergents, and lipids.

Engineering a Transmembrane Nanopore Ion Channel from a Membrane Breaker Peptide.

Re-engineering nature's molecules is an ideal strategy to obtain explicit functionality such as synthetic molecular machines, yet novel strategies for producing engineered molecular channels are few. Here we report a peptide engineering strategy through sequence reversal, which we applied on the first transmembrane peptide of the mycobacteriophage membranoporin protein holin. We have successfully redesigned the membrane rupture property of this peptide to form specific nanopore ion channels.

Current practices in the diagnosis and management of gestational diabetes mellitus in India (WINGS-5).

Aim: To obtain information on existing practices in the diagnosis and management of gestational diabetes mellitus (GDM) among physicians/diabetologists/endocrinologists and obstetricians/gynecologists (OB/GYNs) in India.

Methods: Details regarding diagnostic criteria used, screening methods, management strategies, and the postpartum follow-up of GDM were obtained from physicians/diabetologists/endocrinologists and OB/GYNs across 24 states of India using online/in-person surveys using a structured questionnaire.

Results: A total of 3841 doctors participated in the survey of whom 68.

Prevalence of Gestational Diabetes Mellitus in urban and rural Tamil Nadu using IADPSG and WHO 1999 criteria (WINGS 6).

Background: To determine the prevalence of Gestational Diabetes Mellitus (GDM) in urban and rural Tamil Nadu in southern India, using the International Association of Diabetes and Pregnancy Study Groups (IADPSG) and the World Health Organization (WHO) 1999 criteria for GDM.

Methods: A total of 2121 pregnant women were screened for GDM from antenatal clinics in government primary health centres of Kancheepuram district ( = 520) and private maternity centres in Chennai city in Tamil Nadu ( = 1601) between January 2013 to December 2014. Oral glucose tolerance tests (OGTT) were done after an overnight fast of at least 8 h, using a 75 g glucose load and venous samples were drawn at 0, 1 and 2 h.

Capping β-hairpin with N-terminal d-amino acid stabilizes peptide scaffold.

Various strategies exist to stabilize de novo designed synthetic peptide β-hairpins or β-sheets structures, especially at the non-hydrogen bonding position. However, strategies to stabilize strand termini, which are affected by fraying, are highly limited. Here, by substituting N-terminal aliphatic amino acid with its mirror image counterpart, we achieve a significant increase in scaffold stabilization, resulting from the formation of a terminal aliphatic-aromatic hydrophobic CH…pi cluster.

Quality of life measures in glioma patients with different grades: A preliminary study.

Background: Plethora of information exists in the literature on pathology of the glioma while prevailing research data on quality-of-life (QOL) of glioma patients marks dearth thus demanding more studies.

Aims: In this study, we examined the QOL of different grades of glioma patients among the Chennai population in India.

Materials And Methods: A total of 162 patients with different grades of glioma enrolled from August 2007 to February 2011, at their first contact to Department of Neurology and Neurosurgery, Government General Hospital, Chennai, India were included and their QOL was assessed by European Organization for Research and Treatment of Cancer Core QOL questionnaire (EORTC QLQc-30), EORTC brain cancer module (QLQ BN-20).

Role of cysteines in mammalian VDAC isoforms' function.

In this mini-review, we analyze the influence of cysteines in the structure and activity of mitochondrial outer membrane mammalian VDAC isoforms. The three VDAC isoforms show conserved sequences, similar structures and the same gene organization. The meaning of three proteins encoded in different chromosomes must thus be searched for subtle differences at the amino acid level.

Stereopositional Outcome in the Packing of Dissimilar Aromatics in Designed β-Hairpins.

A popular strategy in the de novo design of stable β-sheet structures for various biomedical applications is the incorporation of aromatic pairs at the non-hydrogen-bonding (NHB) position. However, it is important to explicitly understand how aryl pair packing at the NHB region is coordinated with backbone structural rearrangements, and to delineate the benefits and drawbacks associated with stereopositional choice of dissimilar aromatic pairs. Here, we probe the consequences of flipped Trp/Tyr pairs by using engineered permutants at the NHB position of dodecapeptide β-hairpins, proximal and distal to the turn.

VDAC3 as a sensor of oxidative state of the intermembrane space of mitochondria: the putative role of cysteine residue modifications.

Voltage-Dependent Anion selective Channels (VDAC) are pore-forming mitochondrial outer membrane proteins. In mammals VDAC3, the least characterized isoform, presents a set of cysteines predicted to be exposed toward the intermembrane space. We find that cysteines in VDAC3 can stay in different oxidation states.

VDAC-2: Mitochondrial outer membrane regulator masquerading as a channel?

The voltage-dependent anion channels (VDACs) are the workforce of mitochondrial transport and as such are required for cellular metabolism. The elaborate interplay between mitochondria and the apoptotic pathway supports a role for VDACs as a major regulator of cell death. Although VDAC-1 has an established role in apoptosis and cell homeostasis, the role of VDAC-2 has been controversial.

Molecular Mechanism of Holin Transmembrane Domain I in Pore Formation and Bacterial Cell Death.

Bacterial cell lysis during bacteriophage infection is timed by perfect orchestration between components of the holin-endolysin cassette. In bacteria, progressively accumulating holin in the inner membrane, retained in its inactive form by antiholin, is triggered into active hole formation, resulting in the canonical host cell lysis. However, the molecular mechanism of regulation and physical basis of pore formation in the mycobacterial cell membrane by D29 mycobacteriophage holin, particularly in the nonexistence of a known antiholin, is poorly understood.

Application of Various Statistical Models to Explore Gene-Gene Interactions in Folate, Xenobiotic, Toll-Like Receptor and STAT4 Pathways that Modulate Susceptibility to Systemic Lupus Erythematosus.

Introduction: In view of our previous studies showing an independent association of genetic polymorphisms in folate, xenobiotic, and toll-like receptor (TLR) pathways with the risk for systemic lupus erythematosus (SLE), we have developed three statistical models to delineate complex gene-gene interactions between folate, xenobiotic, TLR, and signal transducer and activator of transcription 4 (STAT4) signaling pathways in association with the molecular pathophysiology of SLE.

Methods: We developed additive, multifactor dimensionality reduction (MDR), and artificial neural network (ANN) models.

Results: The additive model, although the simplest, suggested a moderate predictability of 30 polymorphisms of these four pathways (area under the curve [AUC] 0.

Stevens-Johnson syndrome induced by a combination of lamotrigine and valproic acid.

Lamotrigine and valproic acid are well-tolerated anticonvulsants, but frequently associated with severe cutaneous reactions, such as the Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis, when used in combination. We report a case of SJS likely induced by the use of a lamotrigine and valproic acid regimen and as a dental surgeon it is important to identify such lesion and report to pharmacovigilance.

N-helix and Cysteines Inter-regulate Human Mitochondrial VDAC-2 Function and Biochemistry.

Human voltage-dependent anion channel-2 (hVDAC-2) functions primarily as the crucial anti-apoptotic protein in the outer mitochondrial membrane, and additionally as a gated bidirectional metabolite transporter. The N-terminal helix (NTH), involved in voltage sensing, bears an additional 11-residue extension (NTE) only in hVDAC-2. In this study, we assign a unique role for the NTE as influencing the chaperone-independent refolding kinetics and overall thermodynamic stability of hVDAC-2.

Implications of aromatic-aromatic interactions: From protein structures to peptide models.

With increasing structural information on proteins, the opportunity to understand physical forces governing protein folding is also expanding. One of the significant non-covalent forces between the protein side chains is aromatic-aromatic interactions. Aromatic interactions have been widely exploited and thoroughly investigated in the context of folding, stability, molecular recognition, and self-assembly processes.

The Effect of Synthesis Conditions on Mesoporous Structure and the Photocatalytic Activity of TiO2 Nanoparticles.

Mesoporous TiO2 nanoparticles have been synthesized by sol-gel method in different preparation conditions to investigate the effect of triblock copolymer, acetic acid and water on mesoporous structure and the photocatalytic activity. The synthesized photocatalysts were characterized by means of X-ray powder diffraction, Nitrogen adsorption/desorption studies, High resolution transmission electron microscopy, Scanning electron microscopy, Diffuse reflectance UV-Vis spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and thermogravimetric analysis. Among the various synthesized materials, mesoporous TiO2 synthesized using triblock copolymer as a structure directing template in acetic acid medium with high water ratio calcined at 400 degrees C was found to have the highest photocatalytic activity due to the enhanced band gap energy, high specific surface area and high average pore size.

Residue-Dependent Thermodynamic Cost and Barrel Plasticity Balances Activity in the PhoPQ-Activated Enzyme PagP of Salmonella typhimurium.

PagP is an eight-stranded transmembrane β-barrel enzyme indispensable for lipid A palmitoylation in Gram-negative bacteria. The severity of infection by pathogens, including Salmonella, Legionella, and Bordetella, and resistance to antimicrobial peptides, relies on lipid A remodeling by PagP, rendering PagP a sought-after drug target. Despite a conserved sequence, more robust palmitoylation of lipid A is observed in Salmonella typhimurium compared to Escherichia coli, a possible consequence of the differential regulation of PagP expression and/or specific activity.

Clinical and antimicrobial efficacy of a controlled-release device containing chlorhexidine in the treatment of chronic periodontitis.

A controlled-release device (CRD) containing chlorhexidine gluconate, such as PerioCol(™)CG (Eucare Pharmaceuticals Pvt. Ltd,, Chennai, India), for subgingival application has little reported data with clinical as well as antimicrobial efficacy. This study evaluated clinical and subgingival microbial changes on using indigenously developed PerioCol™CG as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis.

Dimensional change in soft tissues with complete dental prosthesis and its effect on airway space and natural head position.

Background: Insertion of the intraoral prosthesis causes deflection of the tongue, soft palate affecting the patency of the airway.

Aims: To evaluate the cephalometric soft tissue variation in tongue, soft palate, and its effect on posterior airway space in edentulous patients with the insertion of the denture.

Settings And Design: Randomized controlled trial.

Smile: A review.

"Beauty is in the mind of the beholder, each mind perceives a different beauty" famously said by writer Margeret Wolfe Hungerford. A beautiful smile is a gateway to the world. The aim of this article was to identify the criteria for designing the perfect smile.