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Pure frontal plane rotatory dislocation of the ankle joint without an associated fracture is an extremely rare injury. We report one such case of an eversion rotatory dislocation and one case of an inversion rotatory dislocation. To our knowledge, this is the first report of an eversion injury resulting in dislocation of the ankle without fracture. Both patients had low energy trauma, predisposing ligamentous injuries, and recurrent sprains. In the patient with lateral rotatory dislocation, medial malleolar hypoplasia was also a contributing factor. Both patients healed the presenting index injury with nonoperative treatment, whereas the lateral rotatory dislocation had a lateral ankle stabilization to prevent subsequent injury. [ABSTRACT FROM AUTHOR]

In this work, we present the potential of Fourier transform infrared (FTIR) microspectroscopy to compare on whole cells, in an unbiased and untargeted way, the capacity of bacterial lipopolysaccharide (LPS) and two rationally designed molecules (FP20 and FP20Rha) to activate molecular circuits of innate immunity. These compounds are important drug hits in the development of vaccine adjuvants and tumor immunotherapeutics. The biological assays indicated that FP20Rha was more potent than FP20 in inducing cytokine production in cells and in stimulating IgG antibody production post-vaccination in mice. Accordingly, the overall significant IR spectral changes induced by the treatment with LPS and FP20Rha were similar, lipids and glycans signals being the most diagnostic, while the effect of the less potent molecule FP20 on cells resulted to be closer to control untreated cells. We propose here the use of FTIR spectroscopy supported by artificial intelligence (AI) to achieve a more holistic understanding of the cell response to new drug candidates while screening them in cells., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Antonino Natalello reports financial support was provided by University of Milano-Bicocca, Department of Biotechnology and Biosciences. Francesco Peri reports financial support was provided by University of Milano-Bicocca, Department of Biotechnology and Biosciences. Francesco Peri has patent #New synthetic agonists of TLR4 receptor licensed to Licensee. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Vaccines are one of the greatest achievements of modern medicine. Due to their safer profile, the latest investigations usually focus on subunit vaccines. However, the active component often needs to be coupled with an adjuvant to be effective and properly trigger an immune response. We are developing a new synthetic monosaccharide-based TLR4 agonist, such as glucosamine-derived compounds FP18 and FP20 , as a potential vaccine adjuvant. In this study, we present a new FP20 derivative, FP20Hmp , with a hydroxylated ester linked to the glucosamine core. We show that the modification introduced improves the activity of the adjuvant and its solubility. This study presents the synthesis of FP20Hmp , its in vitro characterization, and in vivo activity while coupled with the ovalbumin antigen or in formulation with an enterococcal antigen. We show that FP20Hmp enables increased production of antigen-specific antibodies that bind to the whole bacterium.

Lipopolysaccharide (LPS) mimicry leading to toll-like receptor 4 (TLR4) active compounds has been so far based mainly on reproducing the lipid A portion of LPS. Our work led to a series of structurally simplified synthetic TLR4 agonists in preclinical development as vaccine adjuvants called FPs. FPs bind MD2/TLR4 similarly to lipid A, inserting the lipid chains in the MD2 lipophilic cavity. A strategy to improve FPs' target affinity is introducing a monosaccharide unit in C6, mimicking the first sugar of the LPS core. We therefore designed a panel of FP derivatives bearing different monosaccharides in C6. We report here the synthesis and optimization of FPs' C6 glycosylation, which presented unique challenges and limitations. The biological activity of glycosylated FP compounds was preliminarily assessed in vitro in HEK-Blue cells. The new molecules showed a higher potency in stimulating TLR4 activation when compared to the parent molecule while maintaining TLR4 selectivity., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Emerging pharmacological strategies that target major virulence factors of antibiotic-resistant Mycobacterium tuberculosis (Mtb) are presented and discussed. This review is divided into three parts corresponding to structures and functions important for Mtb pathogenicity: the cell wall, the lipoarabinomannan, and the secretory proteins. Within the cell wall, we further focus on three biopolymeric sub-components: mycolic acids, arabinogalactan, and peptidoglycan. We present a comprehensive overview of drugs and drug candidates that target cell walls, envelopes, and secretory systems. An understanding at a molecular level of Mtb pathogenesis is provided, and potential future directions in therapeutic strategies are suggested to access new drugs to combat the growing global threat of antibiotic-resistant Mtb infection.

We disclose here a panel of small-molecule TLR4 agonists (the FP20 series) whose structure is derived from previously developed TLR4 ligands ( FP18 series). The new molecules have increased chemical stability and a shorter, more efficient, and scalable synthesis. The FP20 series showed selective activity as TLR4 agonists with a potency similar to FP18 . Interestingly, despite the chemical similarity with the FP18 series, FP20 showed a different mechanism of action and immunofluorescence microscopy showed no NF-κB nor p-IRF-3 nuclear translocation but rather MAPK and NLRP3-dependent inflammasome activation. The computational studies related a 3D shape of FP20 series with agonist binding properties inside the MD-2 pocket. FP20 displayed a CMC value lower than 5 μM in water, and small unilamellar vesicle (SUV) formation was observed in the biological activity concentration range. FP20 showed no toxicity in mouse vaccination experiments with OVA antigen and induced IgG production, thus indicating a promising adjuvant activity.

The prefusion conformation of HIV-1 envelope protein (Env) is recognized by most broadly neutralizing antibodies (bnAbs). Studies showed that alterations of its membrane-related components, including the transmembrane domain (TMD) and cytoplasmic tail (CT), can reshape the antigenic structure of the Env ectodomain. Using nuclear magnetic resonance (NMR) spectroscopy, we determine the structure of an Env segment encompassing the TMD and a large portion of the CT in bicelles. The structure reveals that the CT folds into amphipathic helices that wrap around the C-terminal end of the TMD, thereby forming a support baseplate for the rest of Env. NMR dynamics measurements provide evidences of dynamic coupling across the TMD between the ectodomain and CT. Pseudovirus-based neutralization assays suggest that CT-TMD interaction preferentially affects antigenic structure near the apex of the Env trimer. These results explain why the CT can modulate the Env antigenic properties and may facilitate HIV-1 Env-based vaccine design.

Tissue engineering techniques are continuously evolving towards providing better microenvironment along with therapeutic potential to address the skin tissue defects. Factors such as microbial infections, presence of excessive free radicals and depletion in antioxidant based scavenging systems pose serious challenges by prolonging inflammation and delaying the repair process. Incorporation of bioactive molecules in polymer based biomimetic scaffolds may present new vistas for handling chronic wounds. In this study, chitosan/collagen scaffolds incorporating 0.5, 1 and 2% (w/w) silymarin (CS-CO-SM) were synthesized and studied for their biocompatibility, in vitro release kinetics and anti-oxidant activity. The release kinetics of silymarin from the CS-CO-SM scaffold showed an initial burst followed by sustained release. The scaffolds were biocompatible and supported the recovery of COS-7 cells from UV induced oxidative stress. Further the CS-CO-SM (2) scaffolds were used to fabricate a bi-layer scaffold by layer upon layer arrangement with CS-Ag3 (3% Ag, w/w). The Ag was incorporated to impart antimicrobial property to the scaffold. The in vivo studies on bi-layer scaffolds were carried out in Wistar rat models at 3, 7 and 10 days post injury and the skin excisions were studied for wound contraction, histology (H&E staining), and lipid peroxidation. The bi-layer scaffold accelerated the process of wound healing with no inflammatory cells, proliferation of fibroblast, neovascularization and collagen deposition. By day 10 post transplantation of the scaffold, the skin had a structure similar to normal skin with complete re-epithelization. This bi-layer scaffold with antioxidant and antimicrobial properties promotes wound healing and is proposed as a potential tissue engineering material for managing chronic wounds.

HIV-1 envelope glycoprotein (Env), which consists of trimeric (gp160) 3 cleaved to (gp120 and gp41) 3 , interacts with the primary receptor CD4 and a coreceptor (such as chemokine receptor CCR5) to fuse viral and target-cell membranes. The gp120-coreceptor interaction has previously been proposed as the most crucial trigger for unleashing the fusogenic potential of gp41. Here we report a cryo-electron microscopy structure of a full-length gp120 in complex with soluble CD4 and unmodified human CCR5, at 3.9 Å resolution. The V3 loop of gp120 inserts into the chemokine-binding pocket formed by seven transmembrane helices of CCR5, and the N terminus of CCR5 contacts the CD4-induced bridging sheet of gp120. CCR5 induces no obvious allosteric changes in gp120 that can propagate to gp41; it does bring the Env trimer close to the target membrane. The N terminus of gp120, which is gripped by gp41 in the pre-fusion or CD4-bound Env, flips back in the CCR5-bound conformation and may irreversibly destabilize gp41 to initiate fusion. The coreceptor probably functions by stabilizing and anchoring the CD4-induced conformation of Env near the cell membrane. These results advance our understanding of HIV-1 entry into host cells and may guide the development of vaccines and therapeutic agents.

The membrane-proximal external region (MPER) of the HIV-1 envelope glycoprotein (Env) bears epitopes of broadly neutralizing antibodies (bnAbs) from infected individuals; it is thus a potential vaccine target. We report an NMR structure of the MPER and its adjacent transmembrane domain in bicelles that mimic a lipid-bilayer membrane. The MPER lies largely outside the lipid bilayer. It folds into a threefold cluster, stabilized mainly by conserved hydrophobic residues and potentially by interaction with phospholipid headgroups. Antigenic analysis and comparison with published images from electron cryotomography of HIV-1 Env on the virion surface suggest that the structure may represent a prefusion conformation of the MPER, distinct from the fusion-intermediate state targeted by several well-studied bnAbs. Very slow bnAb binding indicates that infrequent fluctuations of the MPER structure give these antibodies occasional access to alternative conformations of MPER epitopes. Mutations in the MPER not only impede membrane fusion but also influence presentation of bnAb epitopes in other regions. These results suggest strategies for developing MPER-based vaccine candidates., Competing Interests: The authors declare no conflict of interest.

Norovirus (NV) RNA-dependent RNA polymerase (RdRP) is essential for replicating the genome of the virus, which makes this enzyme a key target for the development of antiviral agents against NV gastroenteritis. In this work, a complex of NV RdRP bound to manganese ions and an RNA primer-template duplex was investigated using X-ray crystallography and hybrid quantum chemical/molecular mechanical simulations. Experimentally, the complex crystallized in a tetragonal crystal form. The nature of the primer/template duplex binding in the resulting structure indicates that the complex is a closed back-tracked state of the enzyme, in which the 3'-end of the primer occupies the position expected for the post-incorporated nucleotide before translocation. Computationally, it is found that the complex can accept a range of divalent metal cations without marked distortions in the active site structure. The highest binding energy is for copper, followed closely by manganese and iron, and then by zinc, nickel, and cobalt. Proteins 2017; 85:1435-1445. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Bacterial peptidoglycan deacetylase enzymes are potentially important targets for the design of new drugs. In pathogenic bacteria, they modify cell-wall peptidoglycan by removing the acetyl group, which makes the bacteria more resistant to the host's immune response and other forms of attack, such as degradation by lysozyme. In this study, we have investigated the mechanism of reaction of acetyl removal from a model substrate, the N-acetylglucosamine/N-acetylmuramic acid dimer, by peptidogylcan deacetylase from Helicobacter pylori. For this, we employed a range of computational approaches, including molecular docking, Poisson-Boltzmann electrostatic pK a calculations, molecular dynamics simulations, and hybrid quantum chemical/molecular mechanical potential calculations, in conjunction with reaction-path-finding algorithms. The active site of this enzyme is in a region of highly negative electrostatic potential and contains a zinc dication with a bound water molecule. In the docked enzyme-substrate complex, our pK a calculations indicate that in the most stable protonation states of the active site the zinc-bound water molecule is in its hydroxide form and that the adjacent histidine residue, His247, is doubly protonated. In addition, there are one or two excess protons, with the neighboring aspartate residues, Asp12 and/or Asp199, being protonated. Overall, we find five classes of feasible reaction mechanisms, with the favored mechanism depending heavily on the protonation state of the active site. In the major one-excess-proton form, the mechanism with the lowest barrier (84 kJ mol -1 ) involves an initial protonation of the substrate nitrogen, followed by nucleophilic attack of the zinc-bound hydroxide and rupture of the substrate's carbon-nitrogen bond. However, in the minor two-excess-proton form, four mechanisms are almost equienergetic (83-86 kJ mol -1 ), comprising both those that start with nitrogen protonation and those in which nucleophilic attack by hydroxide occurs first.

Bioimaging has drastically transformed the field of medicine, and made the process of diagnosis easy and fast. Visualization of complete organ to complex biological processes has now become possible. Among the various imaging processes, fluorescence imaging using nontoxic fluorescent nanomaterials is advantageous for several beneficial features including high sensitivity, minimal invasiveness, and safe detection limit. In this study, we have synthesized and characterized a new class of nontoxic, self-activated fluorescent hydroxyapatite nanoparticles (fHAps) with different aspect ratios (thin-rods, short-rods, rods) by changing the stabilizing agents (triethyl amine and acetyl acetone) and solvents (water and dimethyl sulfoxide). fHAps showed excellent fluorescence with a broad emission spectrum ranging from 350 to 750 nm and maximum at 502 nm. The presence of fluorescence was attributed to the electronic transition in the asymmetric structure of fHAps as confirmed by ESR spectroscopy and the absence of fluorescence in symmetric HAp NPs. In addition to exceptional fluorescence behavior, these NPs were found to be nontoxic in nature and could be easily internalized in both prokaryotic and eukaryotic systems. We propose that the fHAps provide a safe and a potential alternative to the current fluorescent materials in use for biolabeling and bioimaging applications.

Detection of biomarkers for neurodegenerative disorders (NDDs) within brain tissues of Alzheimer's disease (AD) and Parkinson's disease (PD) patients has always been hampered by our inability to access and biopsy tissue of key brain regions implicated in disease occurrence and progression. Currently, diagnosis of NDDs is principally based on clinical observations of symptoms that present at later stages of disease progression, followed by neuroimaging and, possibly, CSF evaluation. One way to potentially detect and diagnose NDDs at a far earlier stage is to screen for abnormal levels of specific disease markers within the peripheral circulation of patients with NDDs. Increasing evidence suggests that there is dysregulation of microRNAs (miRNAs) in NDDs. Peripheral blood mononuclear cells, as well as biofluids, such as plasma, serum, urine and cerebrospinal fluid, contain miRNAs that can be identified and quantified. Circulating miRNAs within blood and other biofluids may thus be characterized and used as non-invasive, diagnostic biomarkers that facilitate the early detection of disease and potentially the continual monitoring of disease progression for NDDs such as AD and PD. Plainly, such a screen is only possible with a clear understanding of which miRNAs change with disease, and when these changes occur during the progression of AD and PD. Such information is becoming increasingly available and, in the near future, may not only support disease diagnosis, but provide the opportunity to evaluate therapeutic interventions earlier in the disease process.

Pili are fibrous appendages expressed on the surface of a vast number of bacterial species, and their role in surface adhesion is important for processes such as infection, colonization, andbiofilm formation. The human pathogen Streptococcus pneumoniae expresses two different types of pili, PI-1 and PI-2, both of which require the concerted action of structural proteins and sortases for their polymerization. The type PI-1 streptococcal pilus is a complex, well studied structure, but the PI-2 type, present in a number of invasive pneumococcal serotypes, has to date remained less well understood. The PI-2 pilus consists of repeated units of a single protein, PitB, whose covalent association is catalyzed by cognate sortase SrtG-1 and partner protein SipA. Here we report the high resolution crystal structures of PitB and SrtG1 and use molecular modeling to visualize a "trapped" 1:1 complex between the two molecules. X-ray crystallography and electron microscopy reveal that the pneumococcal PI-2 backbone fiber is formed by PitB monomers associated in head-to-tail fashion and that short, flexible fibers can be formed even in the absence of coadjuvant proteins. These observations, obtained with a simple pilus biosynthetic system, are likely to be applicable to other fiber formation processes in a variety of Gram-positive organisms., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background: The Structured Migraine Interview (SMI) is a valid and reliable instrument for migraine diagnosis. However, a Malay version of the SMI is not available to be applied to the local Malaysian population. This study was designed to access the validity and reliability of a new Malay version of the SMI questionnaire., Methods: Patients with headache attending the Neurology Clinic, Hospital Universiti Sains Malaysia, Kelantan, Malaysia, were screened against the inclusion/exclusion criteria before recruitment. A standard translation procedure was used to translate and adapt the questionnaire into the Malay language. The translated version was tested for face, content and construct validities. Subsequently, validity and reliability studies were conducted (1(st) compilation), followed by retesting seven days later (2(nd) compilation)., Results: A total of 157 patients between 15 and 60 years of age were enrolled in this study. The kappa value was 0.70 (p < 0.001) with high sensitivity (0.97) and specificity (0.63). The misclassification rate was 0.15, with a positive predictive value of 0.82 and a negative predictive value of 0.92. The positive likelihood ratio was 2.62, while the negative likelihood ratio was 0.05. The Cronbach's alpha was 0.93 (1(st) compilation) and 0.90 (2(nd) compilation), respectively. The Spearman's correlation coefficient ranged from 0.86 (Question 4) to 0.95 (Question 1). The overall concordance for item 1 was very high (97%), followed by item 4 (83%), item 2 (71%) and finally item 3 (64%)., Conclusion: The Malay version of the SMI questionnaire is comparable to the English version in terms of validity and reliability. It was highly reliable with good internal consistency and can be used for the diagnosis of migraine in clinical settings in Malaysia.

Background: Disability caused by migraine may be one of the main causes of burden contributing to poor quality of life (QOL) among migraine patients. Thus, this study aimed to measure QOL among migraine sufferers in comparison with healthy controls., Methods: Female diagnosed migraine patients (n= 100) and healthy controls (n=100) completed the Malay version of the World Health Organization QOL Brief (WHOQOL-BREF) questionnaire. Only migraine patients completed the Malay version of the Migraine Disability Assessment questionnaire., Results: Females with migraines had significantly lower total WHOQOL-BREF scores (84.3) than did healthy controls (91.9, P<0.001). Similarly, physical health (23.4 versus 27.7, P<0.001) and psychological health scores (21.7 versus 23.2, P< 0.001) were significantly lower than those for healthy controls. Seventy-three percent of patients experienced severe disability, with significantly higher number of days with headaches (13.8 days/3 months, P< 0.001) and pain scores (7.4, P< 0.013). Furthermore, migraine patients with lower total QOL scores had 1.2 times higher odds of having disability than patients with higher total QOL scores., Conclusions: The present study showed that migraine sufferers experienced significantly lower QOL than the control group from a similar population. Disability was severe and frequent and was associated with lower QOL among the migraine patients.

Migraine is the most common form of headache disorder globally. The etiology of migraine is multifactorial, with genetic components and environmental interactions considered to be the main causal factors. Some researchers postulate that deficits in mitochondrial energy reserves can cause migraine or an increase in homocysteine levels can lead to migraine attacks; therefore, vitamins could play a vital role in migraine prevention. For instance, riboflavin influences mitochondrial dysfunction and prevents migraine. Genes such as flavoenzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), especially the C677T variant, have been associated with elevated plasma levels of homocysteine and migraine with aura. Homocysteine catalyzation requires the presence of vitamins B6, B12, and folic acid, which can decrease the severity of migraine with aura, making these vitamins potentially useful prophylactic agents for treating migraine with aura. Menstrual migraine, on the other hand, is associated with increased prostaglandin (PG) levels in the endometrium, indicating a role for vitamin E, which is an anti-PG. Vitamin C can also be used as a scavenger of reactive oxygen species for treating neurogenic inflammation in migraine patients. This paper reviews possible therapies based on vitamin supplementation for migraine prophylaxis, focusing on migraine with aura and menstrual migraine.

Peptidoglycan deacetlyase (HP0310, HpPgdA) from the gram-negative pathogen Helicobacter pylori, is the enzyme responsible for a peptidoglycan modification that counteracts the host immune response. In a recent study, we determined the crystallographic structure of the enzyme, which is a homo-tetramer (Shaik et al., PloS One 2011;6:e19207). The metal-binding site, which is essential for the enzyme's catalytic activity, is visible within the structure, but we were unable to identify the nature of the metal itself. In this study, we have obtained a higher-resolution crystal structure of the enzyme, which shows that the ion bound is, in fact, zinc. Analysis of the structure of the four sites, one per monomer, and quantum chemical calculations of models of the site in the presence of different divalent metal ions show an intrinsic preference for zinc, but also significant flexibility of the site so that binding of other ions can eventually occur., (© 2013 Wiley Periodicals, Inc.)

Pili are surface-attached, fibrous virulence factors that play key roles in the pathogenesis process of a number of bacterial agents. Streptococcus pneumoniae is a causative agent of pneumonia and meningitis, and the appearance of drug-resistance organisms has made its treatment challenging, especially in developing countries. Pneumococcus-expressed pili are composed of three structural proteins: RrgB, which forms the polymerized backbone, RrgA, the tip-associated adhesin, and RrgC, which presumably associates the pilus with the bacterial cell wall. Despite the fact that the structures of both RrgA and RrgB were known previously, structural information for RrgC was still lacking, impeding the analysis of a complete model of pilus architecture. Here, we report the structure of RrgC to 1.85 Å and reveal that it is a three-domain molecule stabilized by two intradomain isopeptide bonds. RrgC does not depend on pilus-specific sortases to become attached to the cell wall; instead, it binds the preformed pilus to the peptidoglycan by employing the catalytic activity of SrtA. A comprehensive model of the type 1 pilus from S. pneumoniae is also presented., (© 2014 by The American Society for Biochemistry and Molecular Biology, Inc.)

Chronic infection can cause slow progressive dementia, cortical atrophy and amyloid deposition in the atrophic form of general paresis. Due to the fact that specific bacterial ligands can increase the expression of proinflammatory molecules that can activate innate and adaptive immune systems, inflammation may play a significant role in the pathogenesis of Alzheimer's disease (AD). Furthermore, there is a significant association between AD and various types of spirochete. Periodontitis is a prevalent and persistent peripheral infection that is associated with gram-negative anaerobic bacteria and is capable of showing localized and systemic infections in the host. Periodontal disease related pathogens and their inflammatory products contribute to systemic inflammation and the pathogenesis of AD. In this minireview, we propose a hypothetical link between periodontitis, type 2 diabetes and AD. We also present the possible mechanistic links between periodontitis-related inflammation, type 2 diabetes and AD. Since this condition is treatable, periodontitis may be a readily-modifiable risk factor for AD.

Alzheimer's disease (AD) is a neurodegenerative disorder that leads to memory problems. It has been associated with type 2 diabetes mellitus at both the molecular and biochemical level. Pancreatic cells have molecular similarities to the brain at the transcriptomic and proteomic levels. Several genes have been reported to be responsible for both AD and diabetes. Currently, no proper treatment is available but various therapeutic approaches are utilized worldwide for the management of these disorders and may be nanoparticles and herbal treatment of Bacopa monnieri will make promise for the treatment of AD in future. The formation of amyloids in neurons and the formation of amylin in pancreatic cells are potential links between these two disorders, which can be silent killers.

Background: Endodontic leakage research focus mainly on the quality of the apical seal of the root canal system and the newly introduced resilon/epiphany system claim to be superior to Gutta-percha in respect to obturation procedure. The aim of this study is to evaluate the root canal obturation completed by resilon/epiphany system., Materials and Methods: A total of 42 teeth were selected and were divided into four groups. Two experimental groups consisted of 15 teeth each and positive control group consisted of eight teeth and negative control group consisted of four teeth. In the experimental groups, Group 1 was obturated with resilon/epiphany system and Group 2 was obturated with Gutta-percha and endofil sealer by lateral condensation technique. The teeth were then immersed in Methelene blue solution and were split longitudinally to access the amount of dye penetrated in the canal. The specimens were viewed under scanning electron microscope to evaluate the adhesion of the obturating material to the root canal walls. Data was subjected to statistical analysis by Analysis of Variance and Bonferroni multiple comparison test at 1% level of significance., Results: The resilon/epiphany system showed better adaptation to the root canal walls, but the difference in dye penetration was not statistically significant when compared to specimens obturated with Gutta-percha and endofil sealer., Conclusion: Although, there was no statistically significant difference between the groups, but resilon/epiphany system showed better adaptation to the root canal walls.

Cognitive decline is a debilitating feature of Alzheimer's disease (AD). The causes leading to such impairment are still poorly understood and effective treatments for AD are still unavailable. Type 2 diabetes mellitus (T2DM) has been identified as a risk factor for AD due to desensitisation of insulin receptors in the brain. Recent studies have suggested that epigenetic mechanisms may also play a pivotal role in the pathogenesis of both AD and T2DM. This article describes the correlation between AD and T2DM and provides the insights to the epigenetics of AD. Currently, more research is needed to clarify the exact role of epigenetic regulation in the course and development of AD and also in relation to insulin. Research conducted especially in the earlier stages of the disease could provide more insight into its underlying pathophysiology to help in early diagnosis and the development of more effective treatment strategies.

In Gram-negative bacteria, nickel uptake is guaranteed by multiple and complex systems that operate at the membrane and periplasmic level. Helicobacter pylori employs other yet uncharacterized systems to import the nickel required for the maturation of key enzymes, such as urease and hydrogenase. H. pylori CeuE protein (HP1561), previously annotated as the periplasmic component of an ATP-binding cassette (ABC)-type transporter apparatus responsible of haem/siderophores or other Fe(III)-complexes uptake, has been recently proposed to be on the contrary involved in nickel/cobalt acquisition. In this work, the crystal structure of H. pylori CeuE has been determined at 1.65 Å resolution using the single anomalous dispersion (SAD) method. It comprises two structurally similar globular domains, each consisting of a central five-stranded β-sheet surrounded by α-helices, an arrangement commonly classified as a Rossmann-like fold. Structurally, H. pylori CeuE belongs to the class III periplasmic substrate-binding protein. Both crystallographic data and fluorescence binding assays allow to exclude a role of the protein in the transport of Vitamin B12, enterobactin, haem and isolated Ni(2+) ions. On the contrary, the crystal structure and plasmon resonance studies about CeuE/Ni-(l-His)2 complex indicate that in H. pylori nickel transport is supported by CeuE protein and requires the presence of a natural nickelophore, analogously to what has been recently demonstrated for NikA from Escherichia coli., (© 2013 John Wiley & Sons Ltd.)

Class B G-protein coupled receptors are involved in a wide variety of diseases and are a major focus in drug design. Migraines are a common problem, and one of their major causative agents is the class B G-protein coupled receptor, Calcitonin gene-related peptide (CGRP) receptor, a target for competitive drug discovery. The calcitonin receptor-like receptor generates complexes with a receptor activity-modifying protein, which determines the type of receptor protein formed. The CGRP receptor comprises a complex formed from the calcitonin receptor-like receptor and receptor activity-modifying protein 1. In this study, an in silico docking approach was used to target the calcitonin receptor-like receptor in the bound form with receptor activity-modifying protein 1 (CGRP receptor), as well as in the unbound form. In both cases, the resulting inhibitors bound to the same cavity of the calcitonin receptor-like receptor. The twelve evaluated compounds were competitive inhibitors and showed efficient inhibitory activity against the CGRP receptor and Calcitonin receptor-like receptor. The two studied quinoline derivatives demonstrated potentially ideal inhibitory activity in terms of binding interactions and low range nano-molar inhibition constants. These compounds could prove helpful in designing drugs for the effective treatment of migraines. We propose that quinoline derivatives possess inhibitory activity by disturbing CGRP binding in the trigeminovascular system and may be considered for further preclinical appraisal for the treatment of migraines., Competing Interests: The authors have no conflict of interests.

Migraine is a neurovascular disease that has classically been attributed to multifactorial aetiologies, with genetic components and environmental interactions considered the main influence. Genes such as flavoenzyme 5, 10- methylenetetrahydrofolate reductase (MTHFR), especially the C677T variant, have been associated with elevated plasma homocysteine levels. This elevation in homocysteine results in an array of metabolic disorders and increased risk of complex diseases, including migraine. Catalysation of homocysteine requires the presence of vitamins B6, B12 and folate. Deficiencies in these cofactor vitamins result in hypomethylation, which triggers migraine. Because migraine predominantly affects females, it is hypothesised that fluctuating oestrogen levels, which are governed by oestrogen receptor 1 polymorphisms, are important. Another important factor is homocysteine, the production of which is dependent upon MTHFR and B vitamins. Gene expression is modulated through epigenetic mechanisms, which involve methionine. Additionally, folate plays a major role in DNA synthesis. We propose that vitamin B intake, coupled with MTHFR and oestrogen receptor 1 polymorphisms, causes differential DNA methylation and gene expression that may contribute to the occurrence of migraine.

Background: The study was designed to determine the validity and reliability of the Bahasa Melayu version (MIDAS-M) of the Migraine Disability Assessment (MIDAS) questionnaire., Methods: Patients having migraine for more than six months attending the Neurology Clinic, Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia, were recruited. Standard forward and back translation procedures were used to translate and adapt the MIDAS questionnaire to produce the Bahasa Melayu version. The translated Malay version was tested for face and content validity. Validity and reliability testing were further conducted with 100 migraine patients (1st administration) followed by a retesting session 21 days later (2nd administration)., Results: A total of 100 patients between 15 and 60 years of age were recruited. The majority of the patients were single (66%) and students (46%). Cronbach's alpha values were 0.84 (1st administration) and 0.80 (2nd administration). The test-retest reliability for the total MIDAS score was 0.73, indicating that the MIDAS-M questionnaire is stable; for the five disability questions, the test-retest values ranged from 0.77 to 0.87., Conclusion: The MIDAS-M questionnaire is comparable with the original English version in terms of validity and reliability and may be used for the assessment of migraine in clinical settings.

Aim: Hyperhomocysteinemia and vitamins B(6), B(9), and B(12) deficiencies usually result in various neurological, vascular, ocular, renal, and pulmonary abnormalities. However, to date, there are no simultaneous detection methods available for determining homocysteine, vitamins B(6), B(9), and B(12) levels in various biological fluids. In this study, we aim to develop a new validated simultaneous detection method for all four compounds to save both cost and time of analysis., Materials and Methods: The mobile phase consisted of a mixture of methanol and 1-heptanesulfonic acid sodium salt (33:67) with 0.05% triethylamine. The pH of the entire mixture was adjusted to 2.3 and the flow rate was 0.5 mL/min. Separation was achieved using a C-18 column (5 μm; 150 mm × 4.6 mm) maintained at 28°C in a column oven and the detection was conducted at 210 nm., Results: The method was linear between 50 and 1600 ng/mL for all of the drugs. The limits of detection for homocysteine, vitamins B(6), B(9), and B(12) were 5, 5, 10, and 10 ng/mL, respectively, while the limits of quantification were 10, 10, 25, and 25 ng/L, respectively. The developed method achieved good precision and accuracy and complies with the Food and Drug Administration (FDA) requirements., Conclusion: The developed and validated method is suitable to be used for the routine analysis of homocysteine, vitamins B(6), B(9), and B(12) simultaneously in human serum.

Based on disability-adjusted life years, stroke is one of the major causes of death and is among the top five diseases in Nepal. Despite this fact, information on the prevalence, morbidity, and mortality of stroke in Nepal is limited to urban areas, with no official reports published on the epidemiology of stroke throughout the country. The mean age of stroke patients in Nepal is between 59 and 62 years, with males affected more frequently. Hypertension, cigarette smoking, alcohol consumption, and diabetes are the main predisposing factors for stroke, and ischemic stroke is more common (63%) than hemorrhagic stroke (37%). Because of a lack of facilities and specialists, most stroke patients, especially in the rural areas, seek traditional healers to treat their conditions. More governmental and non-governmental organizations should be involved in improving facilities and implementing prevention strategies., (© 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.)

Helicobacter pylori, the human pathogen that affects about half of the world population and that is responsible for gastritis, gastric ulcer and adenocarcinoma and MALT lymphoma, owes much of the integrity of its outer membrane on lipopolysaccharides (LPSs). Together with their essential structural role, LPSs contribute to the bacterial adherence properties, as well as they are well characterized for the capability to modulate the immuno-response. In H. pylori the core oligosaccharide, one of the three main domains of LPSs, shows a peculiar structure in the branching organization of the repeating units, which displayed further variability when different strains have been compared. We present here the crystal structure of ADP-L-glycero-D-manno-heptose-6-epimerase (HP0859, rfaD), the last enzyme in the pathway that produces L-glycero-D-manno-heptose starting from sedoheptulose-7-phosphate, a crucial compound in the synthesis of the core oligosaccharide. In a recent study, a HP0859 knockout mutant has been characterized, demonstrating a severe loss of lipopolysaccharide structure and a significant reduction of adhesion levels in an infection model to AGS cells, if compared with the wild type strain, in good agreement with its enzymatic role. The crystal structure reveals that the enzyme is a homo-pentamer, and NAD is bound as a cofactor in a highly conserved pocket. The substrate-binding site of the enzyme is very similar to that of its orthologue in Escherichia coli, suggesting also a similar catalytic mechanism., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Peptidoglycan deacetlyase (HP0310, HpPgdA) from the gram-negative pathogen Helicobacter pylori, has been indicated as the enzyme responsible for a peptidoglycan modification that counteracts the host immune response. HpPgdA has been cloned, purified and expressed in good yield in E. coli. It has been crystallized, its structure determined and activity tests in vitro performed. The enzyme, which belongs to the polysaccharide deacetylases protein family, is a homo-tetramer. The four polypeptide chains, each folded into a single domain characterized by a non-canonical TIM-barrel fold, are arranged around a four-fold symmetry axis. The active site, one per monomer, contains a heavy ion coordinated in a way similar to other deacetylases. However, the enzyme showed no in vitro activity on the typical polysaccharide substrates of peptidoglycan deacetylases. In striking contrast with the known peptidoglycan deacetylases, HpPgdA does not exhibit a solvent-accessible polysaccharide binding groove, suggesting that the enzyme binds a small molecule at the active site.