Search

Abstract: Pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine derivatives such as SCH 442416 display high affinity and selectivity as antagonists for the human A2A adenosine receptor (AR). We extended ether-linked chain substituents at the p-position of the phenyl group using optimized O-alkylation. The conjugates included an ester, carboxylic acid and amines (for amide condensation), an alkyne (for click chemistry), a fluoropropyl group (for 18F incorporation), and fluorophore reporter groups (e.g., BODIPY conjugate 14, K i 15nM). The potent and A2AAR-selective N-aminoethylacetamide 7 and N-[2-(2-aminoethyl)-aminoethyl]acetamide 8 congeners were coupled to polyamidoamine (PAMAM) G3.5 dendrimers, and the multivalent conjugates displayed high A2AAR affinity. Theoretical docking of an AlexaFluor conjugate to the receptor X-ray structure highlighted the key interactions between the heterocyclic core and the binding pocket of the A2AAR as well as the distal anchoring of the fluorophore. In conclusion, we have synthesized a family of high affinity functionalized congeners as pharmacological probes for studying the A2AAR. [Copyright &y& Elsevier]

Abstract: Movement disorders such as Parkinson’s disease and Huntington’s disease are serious life-limiting and debilitating movement disorders. Their onset typically occurs from mid-life to late in life, and effective diagnostic techniques for detecting and following the disease course are lacking. Our goal is to develop receptor imaging agents for positron emission tomography (PET) that selectively target the most relevant subtype of adenosine receptors (AR) that are highly expressed in the striatum, that is, the A2A AR. To further this goal, we have synthesized and characterized pharmacologically a family of high affinity A2A AR ligands, based on the known antagonist, SCH 442416 (R=–Me), which have structural variability on the terminus (R=–Et, –i-Pr, –allyl, and others). A O-fluoroethyl analogue suitable for use as a PET tracer had a K i value of 12.4nM and was highly selective for the A2A AR in comparison to the A1 and A3 ARs. [Copyright &y& Elsevier]

Abstract: Fluorescence polarization (FP) assay has many advantages over the traditional radioreceptor binding studies. We developed an A2A adenosine receptor (AR) FP assay using a newly synthesized fluorescent antagonist of the A2AAR (MRS5346), a pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine derivative conjugated to the fluorescent dye Alexa Fluor-488. MRS5346 displayed a K i value of 111±16nM in radioligand binding using [3H]CGS21680 and membranes prepared from HEK293 cells stably expressing the human A2AAR. In a cyclic AMP functional assay, MRS5346 was shown to be an A2AAR antagonist. MRS5346 did not show any effect on A1 and A3 ARs in binding or the A2BAR in a cyclic AMP assay at 10μM. Its suitability as a fluorescent tracer was indicated in an initial observation of an FP signal following A2AAR binding. The FP signal was optimal with 20nM MRS5346 and 150μg protein/mL HEK293 membranes. The association and dissociation kinetic parameters were readily determined using this FP assay. The K d value of MRS5346 calculated from kinetic parameters was 16.5±4.7nM. In FP competition binding experiments using MRS5346 as a tracer, K i values of known AR agonists and antagonists consistently agreed with K i values from radioligand binding. Thus, this FP assay, which eliminates using radioisotopes, appears to be appropriate for both routine receptor binding and high-throughput screening with respect to speed of analysis, displaceable signal and precision. The approach used in the present study could be generally applicable to other GPCRs. [Copyright &y& Elsevier]

Chemically modified oligonucleotides are increasingly applied in nucleic acid based therapeutics and diagnostics. LNA (locked nucleic acid) and its diastereomer ρ-L-LNA are two promising examples thereof that exhibit increased thermal and enzymatic stability. Herein, the synthesis, biophysical characterization, and molecular modeling of N2'-functionalized 2'-amino-ρ-L-LNA is described. Chemoselective N2'-functionalization of protected amino alcohol 1 followed by phosphitylation afforded a structurally varied set of target phosphoramidites, which were incorporated into oligodeoxyribonucleotides. Incorporation of pyrene-functionalized building blocks such as 2'-N-(pyren-1 -yl)carbonyl-2'-amino-ρ-L-LNA (monomer X) led to extraordinary increases in thermal affinity of up to +19.5 °C per modification against DNA targets in particular. In contrast, incorporation of building blocks with small nonaromatic N2'-functionalities such as 2'-N-acetyl-2'-amino-ρ-L-LNA (monomer V) had detrimental effects on thermal affinity toward DNA/RNA complements with decreases of as much as -16.5 °C per modification. Extensive thermal DNA selectivity, favorable entropic contributions upon duplex formation, hybridization-induced bathochromic shifts of pyrene absorption maxima and increases in circular dichroism signal intensity, and molecular modeling studies suggest that pyrene-functionalized 2'-amino-ρ-L-LNA monomers W-Y having short linkers between the bicyclic skeleton and the pyrene moiety allow high-affinity hybridization with DNA complements and precise positioning of intercalators in nucleic acid duplexes. This rigorous positional control has been utilized for the development of probes for emerging therapeutic and diagnostic applications focusing on DNA targeting. [ABSTRACT FROM AUTHOR]

Background and Objectives: The study was undertaken at Kesariyaji, located in Udaipur district of Rajasthan. There are about 3 million workers who marble mine at Rajasthan. Living conditions of these workers are substandard and most of them are immigrant workers living in tiny shacks. Majority of them belong to lower socioeconomic status with poor educational background. The present study was carried out to estimate dental caries prevalence and treatment needs of laborers working in the green marble mines of Udaipur district. Basic Research Design: The data was collected using the methods and standards recommended by the WHO. Dentition status and treatment needs along with decayed, missing, and filled teeth (DMFT) index, and decayed, missing, and filled surfaces score were recorded. Standard error of mean was calculated for all the mean values of treatment needs. There were three examiners, who were trained before the survey for inter-examiner variability, and the reliability was tested by means of weighted kappa statistics, which was 90%. Participants: The study population comprised 513 men in four age groups of 18-25, 26-34, 35-44, and 45-54 years, respectively. Results: The mean DMFT for all age groups was 3.13 with highest mean of 4.0 for the age group of 45-54 years. Mean decayed teeth were 2.60, 3.33, 1.46, and 1.5 for the age groups 15-24, 25-34, 35-44, and 45-54 years, respectively. Filled component was nil for all age groups. Most of the subjects required one surface filling with a very less proportion needing pulp care. Conclusions: The missing component constituted the major part of DMFT index in the 45-54 years age group and the absence of filled component in the whole study population implies that the treatment needs of the study population are unmet. Thus, intervention in the form of oral health promotion and curative services are the need of the hour. [ABSTRACT FROM AUTHOR]

Abstract Background Traumatic spinal cord injury (SCI) results in upregulation of chondroitin sulfate proteoglycans (CSPGs) by reactive glia that impedes repair and regeneration in the spinal cord. Degradation of CSPGs is known to be beneficial in promoting endogenous repair mechanisms including axonal sprouting/regeneration, oligodendrocyte replacement, and remyelination, and is associated with improvements in functional outcomes after SCI. Recent evidence suggests that CSPGs may regulate secondary injury mechanisms by modulating neuroinflammation after SCI. To date, the role of CSPGs in SCI neuroinflammation remains largely unexplored. The recent discovery of CSPG-specific receptors, leukocyte common antigen-related (LAR) and protein tyrosine phosphatase-sigma (PTPσ), allows unraveling the cellular and molecular mechanisms of CSPGs in SCI. In the present study, we have employed parallel in vivo and in vitro approaches to dissect the role of CSPGs and their receptors LAR and PTPσ in modulating the inflammatory processes in the acute and subacute phases of SCI. Methods In a clinically relevant model of compressive SCI in female Sprague Dawley rats, we targeted LAR and PTPσ by two intracellular functionally blocking peptides, termed ILP and ISP, respectively. We delivered ILP and ISP treatment intrathecally to the injured spinal cord in a sustainable manner by osmotic mini-pumps for various time-points post-SCI. We employed flow cytometry, Western blotting, and immunohistochemistry in rat SCI, as well as complementary in vitro studies in primary microglia cultures to address our questions. Results We provide novel evidence that signifies a key immunomodulatory role for LAR and PTPσ receptors in SCI. We show that blocking LAR and PTPσ reduces the population of classically activated M1 microglia/macrophages, while promoting alternatively activated M2 microglia/macrophages and T regulatory cells. This shift was associated with a remarkable elevation in pro-regenerative immune mediators, interleukin-10 (IL-10), and Arginase-1. Our parallel in vitro studies in microglia identified that while CSPGs do not induce an M1 phenotype per se, they promote a pro-inflammatory phenotype. Interestingly, inhibiting LAR and PTPσ in M1 and M2 microglia positively modulates their inflammatory response in the presence of CSPGs, and harnesses their ability for phagocytosis and mobilization. Interestingly, our findings indicate that CSPGs regulate microglia, at least in part, through the activation of the Rho/ROCK pathway downstream of LAR and PTPσ. Conclusions We have unveiled a novel role for LAR and PTPσ in regulating neuroinflammation in traumatic SCI. Our findings provide new insights into the mechanisms by which manipulation of CSPG signaling can promote recovery from SCI. More importantly, this work introduces the potential of ILP/ISP as a viable strategy for modulating the immune response following SCI and other neuroinflammatory conditions of the central nervous system.

Abstract Background Spinal cord injury (SCI) triggers a robust neuroinflammatory response that governs secondary injury mechanisms with both degenerative and pro-regenerative effects. Identifying new immunomodulatory therapies to promote the supportive aspect of immune response is critically needed for the treatment of SCI. We previously demonstrated that SCI results in acute and permanent depletion of the neuronally derived Neuregulin-1 (Nrg-1) in the spinal cord. Increasing the dysregulated level of Nrg-1 through acute intrathecal Nrg-1 treatment enhanced endogenous cell replacement and promoted white matter preservation and functional recovery in rat SCI. Moreover, we identified a neuroprotective role for Nrg-1 in moderating the activity of resident astrocytes and microglia following injury. To date, the impact of Nrg-1 on immune response in SCI has not yet been investigated. In this study, we elucidated the effect of systemic Nrg-1 therapy on the recruitment and function of macrophages, T cells, and B cells, three major leukocyte populations involved in neuroinflammatory processes following SCI. Methods We utilized a clinically relevant model of moderately severe compressive SCI in female Sprague-Dawley rats. Nrg-1 (2 μg/day) or saline was delivered subcutaneously through osmotic mini-pumps starting 30 min after SCI. We conducted flow cytometry, quantitative real-time PCR, and immunohistochemistry at acute, subacute, and chronic stages of SCI to investigate the effects of Nrg-1 treatment on systemic and spinal cord immune response as well as cytokine, chemokine, and antibody production. Results We provide novel evidence that Nrg-1 promotes a pro-regenerative immune response after SCI. Bioavailability of Nrg-1 stimulated a regulatory phenotype in T and B cells and augmented the population of M2 macrophages in the spinal cord and blood during the acute and chronic stages of SCI. Importantly, Nrg-1 fostered a more balanced microenvironment in the injured spinal cord by attenuating antibody deposition and expression of pro-inflammatory cytokines and chemokines while upregulating pro-regenerative mediators. Conclusion We provide the first evidence of a significant regulatory role for Nrg-1 in neuroinflammation after SCI. Importantly, the present study establishes the promise of systemic Nrg-1 treatment as a candidate immunotherapy for traumatic SCI and other CNS neuroinflammatory conditions.

Introduction: The nucleic acid amplification tests (NAATs): Line probe assay and GeneXpert (Xpert) have evolved as the primary tool for identification of rifampicin (RIF)-resistant (RR) tuberculosis (TB) worldwide, primarily because of the ease and speed. We rechecked RR isolates identified by NAATs from presumptive RR TB cases belonging to South India by the Revised National TB Control Program, India using multiple RIF concentrations on Bactec MGIT system and compared the mutation patterns with the resistance levels. Methodology: Standard protocol for Bactec MGIT system as given by the manufacturer modified for the multiple RIF concentrations was used. All the retests were done in a certified BSL3 laboratory. Results: We found that there is a mismatch of up to 20% (RIF breakpoint 0.5 mg/L); the NAATs probably overidentifying RR TB. Half of the cases with mismatch showed a sub-breakpoint rise in resistance level (0.125 mg/L to 0.5 mg/L RIF). Discussion and Conclusion: The probable reasons for the mismatch are “sub-breakpoint low-level resistance mutants,” hetero-resistant bacterial populations, and other inherent test limitations along with the low RR TB prevalence in South India (

Background: Fluoroquinolones (FQs) are among the most important second-line anti-tuberculosis (TB) drugs, of which 8-methyl FQs; moxifloxacin (MFX) and gatifloxacin are considered to have the most mycobactericidal and “sterilizing action.” Because of the wide and often illogical usage, FQ resistance has evolved and challenged the multidrug-resistant (MDR)/extensively drug-resistant TB (XDRTB) control activities worldwide. We have compared the baseline ofloxacin (OFX) resistance among MDR/rifampicin-resistant (RR) TB cases identified from South Tamil Nadu and Kerala states in India and then assessed the cross-resistance with different concentrations of MFX using MGIT 960. Methods: Bactec MGIT 960 method and the standard protocol as per the manufacturer modified for the multiple concentrations of the drugs were used for the susceptibility testing. Results: We found that samples from newly identified MDR/RR cases of both states have baseline OFX resistance at 16–17%. MFX cross-resistance was 33%–35% (2 mg/L), 59%–70% (1 mg/L), and 87%–93% (0.5 mg/L). Conclusions: As the cross-resistances to MFX 1 mg/L (minimum inhibitory concentration between 1 and 2 mg/L) and 2 mg/L are very high, 59%–70% and 33%–35%, respectively, among newly identified OFX-resistant MDRTB cases, we assume the sterilizing activity of MFX-containing regimens may be seriously compromised leading to higher relapse rates despite having decent cure rates. This may pose considerable technical as well as cost-wise challenges for TB control program in the future.

Abstract: The molecular interaction between adenosine A2A and dopamine D2 receptors (A2ARs and D2Rs, respectively) within an oligomeric complex has been postulated to play a pivotal role in the adenosine–dopamine interplay in the central nervous system, in both normal and pathological conditions (e.g. Parkinson’s disease). While the effects of A2AR challenge on D2R functioning have been largely studied, the reverse condition is still unexplored, a fact that might have impact in therapeutics. Here, we aimed to examine in a real-time mode the D2R-mediated allosteric modulation of A2AR binding when an A2AR/D2R oligomer is established. Thus, we synthesized fluorescent A2AR agonists and evaluated, by means of a flow cytometry homogeneous no-wash assay and a real-time fluorescence resonance energy transfer (FRET)-based approach, the effects on A2AR binding of distinct antiparkinsonian drugs in current clinical use (i.e. pramipexole, rotigotine and apomorphine). Our results provided evidence for the existence of a differential D2R-mediated negative allosteric modulation on A2AR agonist binding that was oligomer-formation dependent, and with apomorphine being the best antiparkinsonian drug attenuating A2AR agonist binding. Overall, the here-developed methods were found valid to explore the ability of drugs acting on D2Rs to modulate A2AR binding, thus serving to facilitate the preliminary selection of D2R-like candidate drugs in the management of Parkinson’s disease. [Copyright &y& Elsevier]

As the incidence of cardiovascular diseases (CVDs) continues to rise among women of childbearing age, the pregnant population with pre-existing heart conditions presents a complex and heterogeneous profile. These women face varying degrees of risk concerning maternal cardiovascular, obstetric, and fetal complications. Effectively managing adverse cardiovascular events during pregnancy presents substantial clinical challenges. The uncertainties surrounding diagnostic and therapeutic approaches create a dynamic landscape with potential implications for maternal and fetal health. Cardio-obstetrics has become increasingly recognized as a vital multidisciplinary field necessitating a collaborative approach to managing cardiovascular conditions during pregnancy. In this review, we aim to provide a thorough and up-to-date examination of the existing evidence, offering a comprehensive overview of strategies and considerations in the management of cardiovascular complications during pregnancy. Special emphasis is placed on the safety assessment of diagnostic procedures and the exploration of treatment options designed to prioritize the well-being of the mother and fetus. We also explore the significance of a multidisciplinary cardio-obstetrics team in providing comprehensive care for women of childbearing age with or at risk for CVD., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

This single case study describes the audiological and vestibular findings of a female patient, aged 62, with diabetes mellitus and rheumatoid arthritis. Based on this case study, we hypothesize that individuals with diabetes mellitus and rheumatoid arthritis are more vulnerable to vestibular impairment. The current findings indicate that central vestibular lesions and bilateral sensorineural hearing loss are related to rheumatoid arthritis and diabetes. Therefore concluding early detection and follow-up is required to understand pathophysiology in detail., (© Association of Otolaryngologists of India 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

A 3 adenosine receptor (A 3 AR) positive allosteric modulators (PAMs) (2,4-disubstituted-1 H -imidazo[4,5- c ]quinolin-4-amines) allosterically increase the E max of A 3 AR agonists, but not potency, due to concurrent orthosteric antagonism. Following mutagenesis/homology modeling of the proposed lipid-exposed allosteric binding site on the cytosolic side, we functionalized the scaffold, including heteroatom substitutions and exocyclic phenylamine extensions, to increase allosteric binding. Strategically appended linear alkyl-alkynyl chains with terminal amino/guanidino groups improved allosteric effects at both human and mouse A 3 ARs. The chain length, functionality, and attachment position were varied to modulate A 3 AR PAM activity. For example, 26 (MRS8247, p -alkyne-linked 8 methylenes) and homologues increased agonist Cl-IB-MECA's E max and potency ([ 35 S]GTPγS binding). The putative mechanism involves a flexible, terminally cationic chain penetrating the lipid environment for stable electrostatic anchoring to cytosolic phospholipid head groups, suggesting "lipid trolling", supported by molecular dynamic simulation of the active-state model. Thus, we have improved A 3 AR PAM activity through rational design based on an extrahelical, lipidic binding site.

Obesity in recent years has become an epidemic. A high body mass index (BMI) is one of today's most crucial population health indicators. BMI does not directly quantify body fat but correlates well with easier body fat measurements. Like smoking, obesity impacts multiple organ systems and is a major modifiable risk factor for countless diseases. Despite this, reports have emerged that obesity positively impacts the prognosis of patients with chronic illnesses such as chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD), a phenomenon known as the Obesity Paradox. This article attempts to explain and summarize this phenomenon. As it stands, two theories explain this paradox. The muscle mass hypothesis states that obese patients are better adapted to tide through acute exacerbations due to increased reserve because of greater muscle mass. The other theory focuses on brown adipose tissue and its anti-inflammatory effects on the body. We performed a literature review on research articles published in English from 1983 to the present in the following databases - PubMed, Elsevier, and Google Scholar. The following search strings and Medical Subject Headings (MeSH) terms were used: "Obesity," "Heart Failure," "COPD," and "Cardio-Respiratory Fitness." In this review, we looked at the obesity paradox in Heart Failure and COPD. We summarized the current literature on the Obesity Paradox and reviewed its relationship with Cardio-Respiratory Fitness., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Giri Ravindran et al.)

The coronavirus disease 2019 (COVID-19) pandemic spread by the single-stranded RNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belongs to the seventh generation of the coronavirus family. Following an unusual replication mechanism, its extreme ease of transmissivity has put many countries under lockdown. With the uncertainty of developing a cure/vaccine for the infection in the near future, the onus currently lies on healthcare infrastructure, policies, government activities, and behaviour of the people to contain the virus. This research uses exponential growth modelling studies to understand the spreading patterns of SARS-CoV-2 and identifies countries that showed early signs of containment until March 26, 2020. Predictive supervised machine learning models are built using infrastructure, environment, policies, and infection-related independent variables to predict early containment. COVID-19 infection data across 42 countries are used. Logistic regression results show a positive significant relationship between healthcare infrastructure and lockdown policies, and signs of early containment. Machine learning models based on logistic regression, decision tree, random forest, and support vector machines are developed and show accuracies between 76.2% and 92.9% to predict early signs of infection containment. Other policies and the decisions taken by countries to contain the infection are also discussed., (© 2020 Wiley-VCH GmbH.)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the seventh-generation coronavirus family causing viral pandemic coronavirus disease (COVID-19) across globe affecting millions of people. The objectives of this study are to (1) identify the major research themes in COVID-19 literature, (2) determine the origin, symptoms and modes of transmission of COVID, (3) recommend the intervention and mitigation strategies adopted by the Governments globally against the spread of COVID-19 and the traumatization among the public? and (4) study the possible drugs/treatment plans against COVID-19. A systematic literature review and comprehensive analysis of 38 research articles on COVID-19 are conducted. An integrated Research focus parallel-ship network and keyword co-occurrence analysis are carried out to visualize the three research concepts in COVID-19 literature. Some of our observations include: (1) as SARS-CoV-2's RNA matches ~ 96% to SARS-CoV, it is assumed to be transmitted from the bats. (2) The common symptoms are high fever, dry cough, fatigue, sputum production, shortness of breath, diarrhoea etc. (3) A lockdown across 180 affected counties for more than a month with social-distancing and the precautions taken in SARS and MERS are recommended by the Governments. (4) Researchers' claim that nutrition and immunity enhancers and treatment plans such as arbidol, lopinavir/ritonavir, convalescent plasma and mesenchymal stem cells and drugs including remdesivir, hydroxychloroquine, azithromycin and favipiravir are effective against COVID-19. This complied report serves as guide to help the administrators, researchers and the medical officers to adopt recommended intervention strategies and the optimal treatment/drug against COVID-19., (© Indian Virological Society 2020.)

Novel pyrene-perylene α-L-LNA FRET pairs described herein effectively detect assembly of 2- and 3-way branched DNA nanostructures prepared by postsynthetic microwave-assisted CuAAC click chemistry. The fluorescent signalling of assembly by internally positioned FRET pairs is achieved with low to no fluorescence background signal, remarkably low limit of target detection values and stabilization of the resulting nanostructures.

The P2Y(1) receptor (P2Y(1)R) is a G protein-coupled receptor naturally activated by extracellular ADP. Its stimulation is an essential requirement of ADP-induced platelet aggregation, thus making antagonists highly sought compounds for the development of antithrombotic agents. Here, through a virtual screening campaign based on a pharmacophoric representation of the common characteristics of known P2Y(1)R ligands and the putative shape and size of the receptor binding pocket, we have identified novel antagonist hits of μM affinity derived from a N,N'-bis-arylurea chemotype. Unlike the vast majority of known P2Y(1)R antagonists, these drug-like compounds do not have a nucleotidic scaffold or highly negatively charged phosphate groups. Hence, our compounds may provide a direction for the development of receptor probes with altered physicochemical properties., (Published by Elsevier Ltd.)

We explored the influence of modifications of uridine 5'-methylenephosphonate on biological activity at the human P2Y(2) receptor. Key steps in the synthesis of a series of 5-substituted uridine 5'-methylenephosphonates were the reaction of a suitably protected uridine 5'-aldehyde with [(diethoxyphosphinyl)methylidene]triphenylphosphorane, C-5 bromination and a Suzuki-Miyaura coupling. These analogues behaved as selective agonists at the P2Y(2) receptor, with three analogues exhibiting potencies in the submicromolar range. Although maximal activities observed with the phosphonate analogues were much less than observed with UTP, high concentrations of the phosphonates had no effect on the stimulatory effect of UTP. These results suggest that these phosphonates bind to an allosteric site of the P2Y(2) receptor., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Molecular modeling of agonist binding to the human A(2A) adenosine receptor (AR) was assessed and extended in light of crystallographic structures. Heterocyclic adenine nitrogens of cocrystallized agonist overlaid corresponding positions of the heterocyclic base of a bound triazolotriazine antagonist, and ribose moiety was coordinated in a hydrophilic region, as previously predicted based on modeling using the inactive receptor. Automatic agonist docking of 20 known potent nucleoside agonists to agonist-bound A(2A)AR crystallographic structures predicted new stabilizing protein interactions to provide a structural basis for previous empirical structure activity relationships consistent with previous mutagenesis results. We predicted binding of novel C2 terminal amino acid conjugates of A(2A)AR agonist CGS21680 and used these models to interpret effects on binding affinity of newly synthesized agonists. d-Amino acid conjugates were generally more potent than l-stereoisomers and free terminal carboxylates more potent than corresponding methyl esters. Amino acid moieties were coordinated close to extracellular loops 2 and 3. Thus, molecular modeling is useful in probing ligand recognition and rational design of GPCR-targeting compounds with specific pharmacological profiles.

P2X receptor activation protects in heart failure models. MRS2339 3, a 2-chloro-AMP derivative containing a (N)-methanocarba (bicyclo[3.1.0]hexane) system, activates this cardioprotective channel. Michaelis-Arbuzov and Wittig reactions provided phosphonate analogues of 3, expected to be stable in vivo due to the C-P bond. After chronic administration via a mini-osmotic pump (Alzet), some analogues significantly increased intact heart contractile function in calsequestrin-overexpressing mice (genetic model of heart failure) compared to vehicle-infused mice (all inactive at the vasodilatory P2Y(1) receptor). Two phosphonates, (1'S,2'R,3'S,4'R,5'S)-4'-(6-amino-2-chloropurin-9-yl)-2',3'-(dihydroxy)-1'-(phosphonomethylene)-bicyclo[3.1.0]hexane, 4 (MRS2775), and its homologue 9 (MRS2935), both 5'-saturated, containing a 2-Cl substitution, improved echocardiography-derived fractional shortening (20.25% and 19.26%, respectively, versus 13.78% in controls), while unsaturated 5'-extended phosphonates, all 2-H analogues, and a CH(3)-phosphonate were inactive. Thus, chronic administration of nucleotidase-resistant phosphonates conferred a beneficial effect, likely via cardiac P2X receptor activation. Thus, we have greatly expanded the range of carbocyclic nucleotide analogues that represent potential candidates for the treatment of heart failure.

We undertook a community-based case-control study on persons with active epilepsy residing in Kerala, southern India. Using a standardized questionnaire, we collected information from 362 cases and 362 controls. In the final multivariate model, family history of epilepsy (odds ratio=7.8, 95% confidence interval=3.2-18.8, P=0.000), antecedent history of febrile seizures (7.7, 4.3-14.0, 0.000), birth by complicated delivery (6.8, 2.1-21.8, 0.001), and neonatal seizures (7.8, 1.7-35.4, 008) emerged as strong independent predictors of epilepsy, followed in decreasing order by mental retardation, prematurity, maternal age 30, perinatal distress, and incomplete immunization. There were more similarities than differences in the distribution of risk factors between generalized and localization-related epilepsy syndromes. Our findings suggest interplay between genetic and acquired factors in the pathogenesis of epilepsies, and underscore the need for improvement in obstetric and neonatal care to minimize the epilepsy burden in low-income countries.

Aims: To assess the oral health status of the Bhil tribal population of Southern Rajasthan and to investigate the association of age, oral hygiene and dental visiting practices with oral health status., Design: A cross sectional study of Bhil tribal adults chosen by a multi stage stratified random sampling procedure., Participants: The total sample size was 1590 male tribal dentate subjects aged 15-54 years., Methods: Clinical recordings of oral hygiene status (OHI-S), caries status (DMFT and DMFS) and treatment needs, and periodontal status (CPI). The Chi square test was applied to discrete data and one way ANOVA for continuous data. Multivariate analyses were carried out to test the association of age, frequency of cleaning teeth, material used for cleaning teeth and dental visiting habits with caries and periodontal status., Results: Debris, calculus and oral hygiene index scores increased with age. The overall mean DMFT and DMFS scores were 5.34 +/- 6.48 and 18.94 +/- 35.87 respectively. Extraction was the most required treatment (1.74 +/- 3.66 teeth) followed by one surface fillings (1.34 +/- 1.65 teeth). Shallow periodontal pockets were prevalent (40%) among the 35-44 years age group whereas deep pockets were most common (11.6%) in the oldest age group. More than half the sextants (3.15) were excluded amongst the oldest study group. All the independent variables namely age, frequency of cleaning teeth, substance used for cleaning teeth and visiting habits were statistically significantly related to caries and periodontal status., Conclusions: The study population was characterised by a lack of previous dental care, high treatment needs, high prevalence of periodontal disease and poor oral hygiene. Under these circumstances, the implementation of a basic oral health care programme for the Bhil population is a high priority.

A synthetic route towards a selected set of N-acylated and N-alkylated derivatives of 2'-amino-alpha-L-LNA phosphoramidite building blocks has been developed. Biophysical studies suggest that the 2-oxo-5-azabicyclo[2.2.1]heptane skeleton of 2'-amino-alpha-L-LNA allows precise positioning of intercalators in the core of nucleic acid duplexes.

Oligodeoxyribonucleotides (ONs) containing two incorporations of 2'-N-(pyren-1-yl)acetyl-2'-amino-alpha-L-LNA monomer Y are sensitive probes for detection of single nucleotide polymorphisms (SNP) in DNA. In addition, the ability of ONs containing pyrene-functionalized 2'-amino-alpha-L-LNA monomers (W-Z) to stabilize duplexes with an abasic site is demonstrated.

Incorporation of a single pyrene-functionalized 2'-amino-alpha-l-LNA monomer X into short DNA strands induces extraordinarily high binding affinity towards complementary DNA (up to 16 degrees C increase per modification), whereas labile duplexes, suitable as probes for targeting of double stranded DNA, are formed upon positioning of two monomers X in an interstrand +1 zipper motif.

A convergent route to 2'-amino-alpha-L-LNA-T phosphoramidite building block 16 has been developed. Key steps include 1) introduction of a C2-azido group prior to nucleobase-coupling, 2) tandem Staudinger and intramolecular nucleophilic substitution reaction, and 3) separation of alpha-L- and beta-L-configured intermediates.