Understanding the influence of antipsychotic drugs on global methylation events and its relevance in treatment response

Aim: The present study intends to evaluate whether antipsychotic drugs can modulate the host epigenome and if so whether drug-induced epigenetic modulation can explain the heterogeneity in drug response. Methods: Present study was conducted in in vitro cells and significance of these in vitro observations was further evaluated in a clinical setting, between drug responsive and nonresponsive schizophrenia patients. A number of DNA modifications were assessed at global level using 5-methylcytosine, 5-hydroxymethylcytosine and 5-formylcytosine followed by evaluating the expression of epigenetic modifier genes and their crosstalk with miRNAs. Results: In vitro data demonstrated that antipsychotic drugs induce epigenetic response by downregulating miRNA that target DNA methyltransferases, resulting in global hypermethylation. Similar trend was observed in clinical setting too and alterations were markedly associated with drug response rather than disease pathogenesis. Conclusion: Study demonstrates that antipsychotic drugs can influence host methylome and thereby indicating its role in mediating a strong pharmacoepigenomic response.

Haloperidol induces pharmacoepigenetic response by modulating miRNA expression, global DNA methylation and expression profiles of methylation maintenance genes and genes involved in neurotransmission in neuronal cells

Introduction

Haloperidol has been extensively used in various psychiatric conditions. It has also been reported to induce severe side effects. We aimed to evaluate whether haloperidol can influence host methylome, and if so what are the possible mechanisms for it in neuronal cells. Impact on host methylome and miRNAs can have wide spread alterations in gene expression, which might possibly help in understanding how haloperidol may impact treatment response or induce side effects.

Methods

SK-N-SH, a neuroblasoma cell line was treated with haloperidol at 10μm concentration for 24 hours and global DNA methylation was evaluated. Methylation at global level is maintained by methylation maintenance machinery and certain miRNAs. Therefore, the expression of methylation maintenance genes and their putative miRNA expression profiles were assessed. These global methylation alterations could result in gene expression changes. Therefore genes expressions for neurotransmitter receptors, regulators, ion channels and transporters were determined. Subsequently, we were also keen to identify a strong candidate miRNA based on biological and in-silico approach which can reflect on the pharmacoepigenetic trait of haloperidol and can also target the altered neuroscience panel of genes used in the study.

Results

Haloperidol induced increase in global DNA methylation which was found to be associated with corresponding increase in expression of various epigenetic modifiers that include DNMT1, DNMT3A, DNMT3B and MBD2. The expression of miR-29b that is known to putatively regulate the global methylation by modulating the expression of epigenetic modifiers was observed to be down regulated by haloperidol. In addition to miR-29b, miR-22 was also found to be downregulated by haloperidol treatment. Both these miRNA are known to putatively target several genes associated with various epigenetic modifiers, pharmacogenes and neurotransmission. Interestingly some of these putative target genes involved in neurotransmission were observed to be upregulated while CHRM2 gene expression was down regulated.

Conclusions

Haloperidol can influence methylation traits thereby inducing a pharmacoepigenomic response, which seems to be regulated by DNMTs and their putative miRNA expression. Increased methylation seems to influence CHRM2 gene expression while microRNA could influence neurotransmission, pharmacogene expression and methylation events. Altered expression of various therapeutically relevant genes and miRNA expression, could account for their role in therapeutic response or side effects.

Pharmacoepigenomic responses of antipsychotic drugs on pharmacogenes are likely to be modulated by miRNAs

Aim: It is imperative to differentiate the role of host epigenetics from pharmacoepigenetics in resolving therapeutic response. Therefore, the objective was to identify how antipsychotic drugs influence epigenetic response on pharmacogenes. Materials & methods: The study design was based on in vitro evaluation of pharmacoepigenetic response of haloperidol, clozapine and olanzapine. Post antipsychotic treatment, the alterations in expression of ABCB1, CYP1A2 and CYP3A4 were monitored, and followed up by promoter methylation and their target miRNA expression studies. Critical observations were followed up in a restrictive clinical setting. Results: Under in vitro conditions increased expression of ABCB1, CYP1A2 and CYP3A4 was observed which seems to be regulated by miR-27a and miR-128a and not by methylation. A similar pattern was observed in clinical setting with ABCB1, which was reflective of good therapeutic response. Conclusion: The study demonstrates that antipsychotic drugs can influence miRNA-mediated epigenetic response in pharmacogenes resulting in modulating therapeutic response.

Understanding epigenetics of schizophrenia in the backdrop of its antipsychotic drug therapy

The diatheses of gene and environment interaction in schizophrenia (SCZ) are becoming increasingly evident. Genetic and epigenetic backgrounds are being considered in stratifying and addressing phenotypic variation and drug response in SCZ. But how much of these epigenetic alterations are the primary contributing factor, toward disease pathogenesis and drug response, needs further clarity. Evidence indicates that antipsychotic drugs can also alter the epigenetic homeostasis thereby inducing pharmacoepigenomic effects. We re-examine the context of epigenetics in disease pathogenesis and antipsychotic drug therapy in SCZ to understand how much of these observations act as real indicators of the disease or therapeutic response. We propose that epigenetic viewpoint in SCZ needs to be critically examined under the genetic, epigenetic and pharmacoepigenetic background.

Role of pRIFLE Criteria in Early Diagnosis of Severity Staging of Neonatal AKI and its Impact on Management

Mortality is high among sick neonates who have concomitant acute kidney injury (AKI). This observational study was done at Special Care Baby Unit (SCABU) of Dhaka Medical College Hospital (DMCH), Bangladesh from October 2013 to March 2014 to find out the role of pRIFLE criteria in prediction of severity stages of AKI in neonate and early intervention to see the immediate outcome. A total of 44 neonates with AKI were included, all were treated conservatively and with intermittent peritoneal dialysis (IPD) as needed. The neonate of ≤7 days old comprised the main bulk (n=28) and M: F = 21: 23. The diagnosis was based on eCCL criteria of pRIFLE showed that 40.9% neonates were at risk of AKI, 20.5% have had already injured. Higher proportions of neonates were classified as failure (38.6%). The distribution of biochemical parameters among three stages of AKI showed serum potassium was significantly higher in failure group (p<0.001). The serum creatinine both at baseline and at next evaluations were significantly raised in the failure group (p<0.001). However, failure group had a significantly longer hospital stay compared to risk and injury group (p<0.001). Multiorgan failure was found to be lower in the risk group compared to other two groups (p=0.026). Majority of the failure group needed dialysis as compared to the risk and injury group (p<0.001). The mortality was progressively higher from risk to failure groups (p=0.106). Overall 27% of the neonates diagnosed AKI by pRIFLE were died of the disease. The study concluded that pRIFLE staging in AKI is useful and sensitive in the diagnosis and management of AKI in neonates.

Prey-predator model with a nonlocal consumption of prey

The prey-predator model with nonlocal consumption of prey introduced in this work extends previous studies of local reaction-diffusion models. Linear stability analysis of the homogeneous in space stationary solution and numerical simulations of nonhomogeneous solutions allow us to analyze bifurcations and dynamics of stationary solutions and of travelling waves. These solutions present some new properties in comparison with the local models. They correspond to different feeding strategies of predators observed in ecology.

Inter- and intraobserver reliability of the Rockwood classification in acute acromioclavicular joint dislocations

PURPOSE

The reliability of the Rockwood classification, the gold standard for acute acromioclavicular (AC) joint separations, has not yet been tested. The purpose of this study was to investigate the reliability of visual and measured AC joint lesion grades according to the Rockwood classification.

METHODS

Four investigators (two shoulder specialists and two second-year residents) examined radiographs (bilateral panoramic stress and axial views) in 58 patients and graded the injury according to the Rockwood classification using the following sequence: (1) visual classification of the AC joint lesion, (2) digital measurement of the coracoclavicular distance (CCD) and the horizontal dislocation (HD) with Osirix Dicom Viewer (Pixmeo, Switzerland), (3) classification of the AC joint lesion according to the measurements and (4) repetition of (1) and (2) after repeated anonymization by an independent physician. Visual and measured Rockwood grades as well as the CCD and HD of every patient were documented, and a CC index was calculated (CCD injured/CCD healthy). All records were then used to evaluate intra- and interobserver reliability.

RESULTS

The disagreement between visual and measured diagnosis ranged from 6.9 to 27.6 %. Interobserver reliability for visual diagnosis was good (0.72-0.74) and excellent (0.85-0.93) for measured Rockwood grades. Intraobserver reliability was good to excellent (0.67-0.93) for visual diagnosis and excellent for measured diagnosis (0.90-0.97). The correlations between measurements of the axial view varied from 0.68 to 0.98 (good to excellent) for interobserver reliability and from 0.90 to 0.97 (excellent) for intraobserver reliability.

CONCLUSION

Bilateral panoramic stress and axial radiographs are reliable examinations for grading AC joint injuries according to Rockwood's classification. Clinicians of all experience levels can precisely classify AC joint lesions according to the Rockwood classification. We recommend to grade acute ACG lesions by performing a digital measurement instead of a sole visual diagnosis because of the higher intra- and interobserver reliability.

LEVEL OF EVIDENCE

Case series, Level IV.

Evaluation of salivary DNA obtained from dental prosthesis and its applicability in forensic investigations

AIM

This study evaluated the salivary DNA obtained from dental prosthesis after a period of storage and its applicability in human identification.

MATERIAL AND METHODS

In first phase, DNA was extracted after a span of 1 week and 1 month from the dental prosthesis dipped in whole saliva for 15 min. It was followed by PCR and electrophoresis. In second phase, from extracted DNA samples 15 STRs (short tandem repeats) of human genomic DNA were amplified via polymerase chain reaction.

RESULTS & CONCLUSION

DNA isolated from saliva stained dental prosthesis after a period of storage and the techniques employed are adequate for further forensic analysis.

Dopamine D3 receptor Ser9Gly variant is associated with impulse control disorders in Parkinson's disease patients

INTRODUCTION

Impulse control disorders (ICD) are reported to occur at variable frequencies in different ethnic groups. Genetic vulnerability is suspected to underlie the individual risk for ICD. We investigated whether the allelic variants of dopamine (DRD3), glutamate (GRIN2B) and serotonin (HTR2A) receptors are linked to ICD in Indian Parkinson's disease (PD) patients.

METHODS

We conducted a prospective, case-control study which included PD patients (70 with ICD, 100 without ICD categorized after direct psychiatric interview of patient and caregiver) and 285 healthy controls. Single nucleotide polymorphism (SNP) variants of DRD3 p.S9G (rs6280), GRIN2B c.2664C>T (rs1806201) and HTR2A c.102T>C (rs6313) were genotyped.

RESULTS

Multivariate regression analysis revealed that DRD3 p.Ser9Gly (rs6280) heterozygous variant CT (OR = 2.22, 95% CI: 1.03-4.86, p = 0.041), higher daily Levodopa equivalent doses (LED) of drugs (for 100 mg LED, OR = 1.14, 95% CI: 1.01-1.29, p = 0.041), current dopamine agonist but not Levodopa use (OR = 2.16, 95% CI: 1.03-4.55, p = 0.042) and age of onset of motor symptoms under 50 years (OR 2.09, 95% CI: 1.05-4.18, p = 0.035) were independently associated with ICD.

CONCLUSION

DRD3 p.Ser9Gly (rs6280) CT genotype is associated with ICD in Indian PD patients and this association is novel. Enhanced D3 receptor affinity due to gain-of-function conferred by the glycine residues could impair reward-risk assessment in the mesolimbic system and contribute to development of impulsive behaviour, in carriers of this genotype.

Pro-inflammatory cytokines and their epistatic interactions in genetic susceptibility to schizophrenia

Background

In schizophrenia, genetic background may provide a substrate for intrinsic maldevelopment of the brain through environmental influences, by recruiting neurotrophic factors and cytokines, to trigger the changes that lead to impaired neuronal functions. Cytokines being the key regulators of immune/inflammatory reactions are also known to influence the dopaminergic, noradrenergic, and serotonergic neurotransmission. Therefore, functional polymorphisms in cytokine genes may result in imbalances in the pro- and anti-inflammatory cytokine production.

Methods

We screened polymorphisms in pro- and anti-inflammatory cytokine genes using a case-control association study in a South Indian population. The role of allele, genotype, haplotype, and diplotypes of these cytokine genes and their epistatic interactions were assessed in contributing to the risk of developing schizophrenia. Meta-analysis for the reported associations was also monitored for global significance.

Results

The pro-inflammatory cytokine gene polymorphisms in IL1Ars1800587, IL6rs1800796, TNFArs361525, and IFNGrs2069718 were associated with schizophrenia. The study also provides significant evidence for strong epistatic interactions among pro-inflammatory cytokine genes IL6 and IFNG in the development of schizophrenia. In silico analysis suggested that associated risk variants were indicative of altered transcriptional activity with higher production of IL1α, IL-6, TNF-α, and IFN-ɤ cytokines. Meta-analysis indicated heterogeneity among study population while IL1Ars1800587 was found to be globally significant.

Conclusions

It is important to identify the nature of inflammatory response that can be amplified by the environment, to influence either Th1 response or Th2 response. The associated functional variants in the study are involved with increased expression resulting in higher production of the pro-inflammatory cytokines IL-1α, IL-6, TNF-α, and IFN-γ. The interaction of immunological stressors with these high producer alleles of pro-inflammatory cytokines may suggest that even a lower threshold may be sufficient to induce a resultant chronic effect on the psycho-social and environmental stressors that may result in the development and pathogenesis of schizophrenia. Understanding environmental factors that influence the expression of these pro-inflammatory cytokine genes or their interaction can possibly help in dissecting the phenotypic variation and therapeutic response to antipsychotics in schizophrenia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-016-0569-8) contains supplementary material, which is available to authorized users.

Long-term transients and complex dynamics of a stage-structured population with time delay and the Allee effect

Traditionally, mathematical modeling in population ecology is mainly focused on asymptotic behavior of the model, i.e. as given by the system attractors. Recently, however, transient regimes and especially long-term transients have been recognized as playing a crucial role in the dynamics of ecosystems. In particular, long-term transients are a potential explanation of ecological regime shifts, when an apparently healthy population suddenly collapses and goes extinct. In this paper, we show that the interplay between delay in maturation and a strong Allee effect can result in long-term transients in a single species system. We first derive a simple 'conceptual' model of the population dynamics that incorporates both a strong Allee effect and maturation delay. Unlike much of the previous work, our approach is not empirical since our model is derived from basic principles. We show that the model exhibits a high complexity in its asymptotic dynamics including multi-periodic and chaotic attractors. We then show the existence of long-term transient dynamics in the system, when the population size oscillates for a long time between locally stable stationary states before it eventually settles either at the persistence equilibrium or goes extinct. The parametric space of the model is found to have a complex structure with the basins of attraction corresponding to the persistence and extinction states being of a complicated shape. This impedes the prediction of the eventual fate of the population, as a small variation in the maturation delay or the initial population size can either bring the population to extinction or ensure its persistence.

Patterns of early resuscitation associated with mortality after penetrating injuries

BACKGROUND

Penetrating injuries are rare in European populations so their management represents a particular challenge. The aim was to assess early therapeutic aspects that are associated with favourable outcomes in patients with penetrating trauma.

METHODS

Patients with penetrating injuries documented from 2009 to 2013 in the TraumaRegister DGU® were analysed. Patients with a primary admission and an Injury Severity Score (ISS) of at least 9 were included. The Revised Injury Severity Classification (RISC) II score was used for mortality prediction, and a standardized mortality ratio (SMR) calculated per hospital. Hospitals with favourable outcome (SMR below 1) were compared with those with poor outcome (SMR 1 or more).

RESULTS

A total of 50 centres had favourable outcome (1242 patients; observed mortality rate 15.7 per cent) and 34 centres had poor outcome (918 patients; observed mortality rate 24.4 per cent). Predicted mortality rates according to RISC-II were 20.4 and 20.5 per cent respectively. Mean(s.d.) ISS values were 22(14) versus 21(14) (P = 0.121). Patients in the favourable outcome group had a significantly shorter time before admission to hospital and a lower intubation rate. They received smaller quantities of intravenous fluids on admission to the emergency room, but larger amounts of fresh frozen plasma, and were more likely to receive haemostatic agents. A higher proportion of patients in the favourable outcome group were treated in a level I trauma centre. Independent risk factors for hospital death following penetrating trauma identified by multivariable analysis included gunshot injury mechanism and treatment in non-level I centres.

CONCLUSION

Among penetrating traumas, gunshot injuries pose an independent risk of death. Treatment of penetrating trauma in a level I trauma centre was significantly and independently associated with lower hospital mortality.

Pathogenesis of intracranial aneurysm is mediated by proinflammatory cytokine TNFA and IFNG and through stochastic regulation of IL10 and TGFB1 by comorbid factors

BACKGROUND

Intracranial aneurysm (IA) is often asymptomatic until the time of rupture resulting in subarachnoid hemorrhage (SAH).There is no precise biochemical or phenotype marker for diagnosis of aneurysm. Environmental risk factors that associate with IA can result in modifying the effect of inherited genetic factors and thereby increase the susceptibility to SAH. In addition subsequent to aneurismal rupture, the nature and quantum of inflammatory response might be critical for repair. Therefore, genetic liability to inflammatory response caused by polymorphisms in cytokine genes might be the common denominator for gene and environment in the development of aneurysm and complications associated with rupture.

METHODS

Functionally relevant polymorphisms in the pro- and anti-inflammatory cytokine genes IL-1 complex (IL1A, IL1B, and IL1RN), TNFA, IFNG, IL3, IL6, IL12B, IL1RN, TGFB1, IL4, and IL10] were screened in radiologically confirmed 220 IA patients and 250 controls from genetically stratified Malayalam-speaking Dravidian ethnic population of south India. Subgroup analyses with genetic and environmental variables were also carried out.

RESULTS

Pro-inflammatory cytokines TNFA rs361525, IFNG rs2069718, and anti-inflammatory cytokine IL10 rs1800871 and rs1800872 were found to be significantly associated with IA, independent of epidemiological factors. TGFB1 rs1800469 polymorphism was observed to be associated with IA through co-modifying factors such as hypertension and gender. Functional prediction of all the associated SNPs of TNFA, IL10, and TGFB1 indicates their potential role in transcriptional regulation. Meta-analysis further reiterates that IL1 gene cluster and IL6 were not associated with IA.

CONCLUSIONS

The study suggests that chronic exposure to inflammatory response mediated by genetic variants in pro-inflammatory cytokines TNFA and IFNG could be a primary event, while stochastic regulation of IL10 and TGFB1 response mediated by comorbid factors such as hypertension may augment the pathogenesis of IA through vascular matrix degradation. The implication and interaction of these genetic variants under a specific environmental background will help us identify the resultant phenotypic variation in the pathogenesis of intracranial aneurysm. Identifying genetic risk factors for inflammation might also help in understanding and addressing the posttraumatic complications following the aneurismal rupture.

Cissus quadrangularis Linn exerts dose-dependent biphasic effects: osteogenic and anti-proliferative, through modulating ROS, cell cycle and Runx2 gene expression in primary rat osteoblasts

OBJECTIVES

This report highlights phytoconstituents present in Cissus quadrangularis (CQ) extract and examines biphasic (proliferative and anti-proliferative) effects of its extract on bone cell proliferation, differentiation, mineralization, ROS generation, cell cycle progression and Runx2 gene expression in primary rat osteoblasts.

MATERIALS AND METHODS

Phytoconstituents were identified using gas chromatography-mass spectroscopy (GC-MS). Osteoblasts were exposed to different concentrations (10-100 μg/ml) of CQ extract and cell proliferation and cell differentiation were investigated at different periods of time. Subsequently, intracellular ROS intensity, apoptosis and matrix mineralization of osteoblasts were evaluated. We performed flow cytometry for DNA content and real-time PCR for Runx2 gene expression analysis.

RESULTS

CQ extract's approximately 40 bioactive compounds of fatty acids, hydrocarbons, vitamins and steroidal derivatives were identified. Osteoblasts exposed to varying concentrations of extract exhibited biphasic variation in cell proliferation and differentiation as a function of dose and time. Moreover, lower concentrations (10-50 μg/ml) of extract slightly reduced ROS intensity, although they enhanced matrix mineralization, DNA content in S phase of the cell cycle, and levels of Runx2 expression. However, higher concentrations (75-100 μg/ml) considerably induced the ROS intensity and nuclear condensation in osteoblasts, while it reduced mineralization level, proportion of cells in S phase and Runx2 level of the osteogenic gene.

CONCLUSIONS

These findings suggest that CQ extract revealed concentration-dependent biphasic effects, which would contribute notably to future assessment of pre-clinical efficacy and safety studies.

5-Hydroxytryptamine (serotonin) 2A receptor gene polymorphism is associated with schizophrenia

BACKGROUND & OBJECTIVES

Schizophrenia, the debilitating neuropsychiatric disorder, is known to be heritable, involving complex genetic mechanisms. Several chromosomal regions associated with schizophrenia have been identified during the past; putative gene (s) in question, to be called the global signature for the pathophysiology of the disease, however, seems to evade us. The results obtained from the several population-wise association-non association studies have been diverse. w0 e therefore, undertook the present study on Tamil speaking population in south India to examine the association between the single nucleotide polymorphisms (SNPs) at the serotonin receptor gene (5HT2A) and the occurrence of the disease.

METHODS

Blood samples collected from 266 cases and 272 controls were subjected to genotyping (PCR amplification of candidate SNPs, RFLP and sequencing). The data on the SNPs were subjected to statistical analysis for assessing the gene frequencies in both the cases and the controls.

RESULTS

The study revealed significant association between the genotypic frequencies of the serotonin receptor polymorphism and schizophrenia. SNP analysis revealed that the frequencies of GG (30%, rs6311) and CC genotypes (32%, rs6313), were higher in patients (P<0.05) than in controls. The study also showed presence of G and C alleles in patients. s0 ignificant levels of linkage disequilibrium (LD) were found to exist between the genotype frequencies of rs6311 and rs6313.

INTERPRETATION & CONCLUSIONS

This study indicated an association between the SNPs (rs6311 and rs6313) of the serotonin receptor 5HT2A and schizophrenia. HapMap analysis revealed that in its genotype distribution, the Tamil speaking population was different from several other populations across the world, signifying the importance of such ethnicity-based studies to improve our understanding of this complex disease.

Association of Versican (VCAN) gene polymorphisms rs251124 and rs2287926 (G428D), with intracranial aneurysm

Intracranial aneurysm (IA) accounts for 85% of Subarachnoid Hemorrhage (SAH) and is mainly caused due to the weakening of arterial wall. The structural integrity of the intracranial arteries is mainly influenced by the extracellular matrix (ECM) remodeling. The Proteoglycan Versican plays an important role in extracellular matrix assembly and plays a major role in the pathogenesis of IA. The linkage studies also indicated VCAN as a putative candidate gene for IA in the 5q22-31 region. Using a case-control study design, we tested the hypothesis whether the variants in VCAN gene, nonsynonymous variants in the coding region of Glycosaminoglycan α (GAG-α) and GAG-β and two reported SNPs involved in splicing rs251124 and rs173686 can increase the risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. We selected 200 radiologically confirmed aneurysmal cases and 250 ethnically, age and sex matched controls from the Dravidian Malayalam speaking population of South India. The present study reiterated the earlier association of rs251124 with intracranial aneurysm (P = 0.0002) and also found a novel association with rs2287926 (G428D) in exon 7 coding for GAG-α with intracranial aneurysm (P = 0.0015). Interestingly, both these SNPs contributed to higher risk for aneurysm in males. In-silico analysis predicted this SNP to have the highest functional relevance in the gene which might have a potentially altered regulatory role in transcription and splicing. Using meta-analysis with available literature rs251124 was found to be the strongest intracranial aneurysm marker for global ethnicities. This study with a novel functional SNP rs2287926 (G428D) further substantiates the potential role of VCAN in the pathogenesis of IA.

Association of Superoxide dismutases (SOD1 and SOD2) and Glutathione peroxidase 1 (GPx1) gene polymorphisms with type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a metabolic disorder resulting from oxidative stress (OS), the root cause of insulin resistance, β-cell dysfunction, and impaired glucose tolerance. Antioxidant enzymes play key roles in cellular defense and can be used as important biomarkers for T2DM. The present study was undertaken to evaluate three genetic polymorphisms viz. SOD1 + 35A/C, SOD2 + 47C/T, and GPx + 599C/T in 207 T2DM cases and 210 healthy controls from North India. DNA was extracted from blood samples and genotyping was done by PCR-RFLP. Genotypic/allelic frequencies and haplotype/gene-gene interaction analysis were performed using SPSS (version 15.0) and SHEsis (v. online). Except age, all other biochemical parameters showed highly significant association in T2DM cases (P < 0.001). In North Indian population, SOD1 + 35A/C variant was monomorphic. Genotype/allele frequencies of SOD2 + 47C/T polymorphism and carriage rate of 'C' allele showed significant association (p < 0.05, < 0.001; OR 2.434). Genotype/allele frequencies of GPx1 + 599C/T and carriage rate showed no association although the odds ratio of GPx1 'C' allele indicated a 1.362 times higher risk of T2DM. SOD2 'CT' and GPx1 'CC' genotypes showed maximum association with biochemical parameters. Haplotype/gene-gene interaction analysis in controls and cases showed that SOD2 + 47C/T and GPx1 + 599C/T were in linkage disequilibrium (D: 0.168; r(2): 0.10) and individuals with this combination had a 1.273 times higher risk [OR; CI (95%)] of developing T2DM. Thus, we conclude that it is essential to assess the combinatorial association of gene variants with T2DM in order to identify risk haplotypes in a population.

Pharmacogenetic evaluation of ABCB1, Cyp2C9, Cyp2C19 and methylene tetrahydrofolate reductase polymorphisms in teratogenicity of anti-epileptic drugs in women with epilepsy

Aim:

Pregnancy in women with epilepsy (WWE) who are on anti-epileptic drugs (AEDs) has two- to three-fold increased risk of fetal malformations. AEDs are mostly metabolized by Cyp2C9, Cyp2C19 and Cyp3A4 and transported by ABCB1. Patients on AED therapy can have folate deficiency. We hypothesize that the polymorphisms in ABCB1, Cyp2C9, Cyp2C19 and methylene tetrahydrofolate reductase (MTHFR) might result in differential expression resulting in differential drug transport, drug metabolism and folate metabolism, which in turn may contribute to the teratogenic impact of AEDs.

Materials and Methods:

The ABCB1, Cyp2C9, Cyp2C19 and MTHFR polymorphisms were genotyped for their role in teratogenic potential and the nature of teratogenecity in response to AED treatment in WWE. The allelic, genotypic associations were tested in 266 WWE comprising of 143 WWE who had given birth to babies with WWE-malformation (WWE-M) and 123 WWE who had normal offsprings (WWE-N).

Results:

In WWE-M, CC genotype of Ex07 + 139C/T was overrepresented (P = 0.0032) whereas the poor metabolizer allele *2 and *2 *2 genotype of CYP2C219 was significantly higher in comparison to WWE-N group (P = 0.007 and P = 0.005, respectively). All these observations were independent of the nature of malformation (cardiac vs. non cardiac malformations).

Conclusion:

Our study indicates the possibility that ABCB1 and Cyp2C19 may play a pivotal role in the AED induced teratogenesis, which is independent of nature of malformation. This is one of the first reports indicating the pharmacogenetic role of Cyp2C19 and ABCB1 in teratogenesis of AED in pregnant WWE.

DNA methyl transferase (DNMT) gene polymorphisms could be a primary event in epigenetic susceptibility to schizophrenia

DNA methylation has been implicated in the etiopathology of various complex disorders. DNA methyltransferases are involved in maintaining and establishing new methylation patterns. The aim of the present study was to investigate the inherent genetic variations within DNA methyltransferase genes in predisposing to susceptibility to schizophrenia. We screened for polymorphisms in DNA methyltransferases, DNMT1, DNMT3A, DNMT3B and DNMT3L in 330 schizophrenia patients and 302 healthy controls for association with Schizophrenia in south Indian population. These polymorphisms were also tested for subgroup analysis with patient's gender, age of onset and family history. DNMT1 rs2114724 (genotype P = .004, allele P = 0.022) and rs2228611 (genotype P = 0.004, allele P = 0.022) were found to be significantly associated at genotypic and allelic level with Schizophrenia in South Indian population. DNMT3B rs2424932 genotype (P = 0.023) and allele (P = 0.0063) increased the risk of developing schizophrenia in males but not in females. DNMT3B rs1569686 (genotype P = 0.027, allele P = 0.033) was found to be associated with early onset of schizophrenia and also with family history and early onset (genotype P = 0.009). DNMT3L rs2070565 (genotype P = 0.007, allele P = 0.0026) confers an increased risk of developing schizophrenia at an early age in individuals with family history. In-silico prediction indicated functional relevance of these SNPs in regulating the gene. These observations might be crucial in addressing and understanding the genetic control of methylation level differences from ethnic viewpoint. Functional significance of genotype variations within the DNMTs indeed suggest that the genetic nature of methyltransferases should be considered while addressing epigenetic events mediated by methylation in Schizophrenia.

Genetic association analysis of ATP binding cassette protein family reveals a novel association of ABCB1 genetic variants with epilepsy risk, but not with drug-resistance

Epilepsy constitutes a heterogeneous group of disorders that is characterized by recurrent unprovoked seizures due to widely different etiologies. Multidrug resistance remains a major issue in clinical epileptology, where one third of patients with epilepsy continue to have seizures. Role of efflux transporters in multidrug resistant epilepsy has been attributed to drug-resistant epilepsy although, with discrepant observation in genetic studies. These discrepancies could be attributed to variety of factors such as variable definition of the anti-epileptic drug (AED)-resistance, variable epilepsy phenotypes and ethnicities among the studies. In the present study we inquired the role of multidrug transporters ABCB1 and ABCG2 variants in determining AED-resistance and susceptibility to epilepsy in three well-characterized cohorts comprising of mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) (prototype for AED-resistant epilepsy); juvenile myoclonic epilepsy (JME) (prototype for AED-responsive epilepsy); and healthy non-epileptic controls, in 738 subjects of Malayalam speaking south Indian ancestry. ABCB1 and ABCG2 variants were not found to be associated with drug resistance when AED-resistant and AED-responsive cohorts were compared. However, a significant association was observed between ABCB1 (C3435T) rs1045642 and risk of having epilepsy (MTLE-HS and JME pooled cohort; genotypic p-value = 0.0002; allelic p-value = 0.004). This association was seen persistent with MTLE-HS (genotypic p-value = 0.0008; allelic p-value = 0.004) and also with JME (genotypic p-value = 0.01; allelic p-value = 0.05) cohort individually. In-silico functional prediction indicated that ABCB1 rs1045642 has a deleterious impact on protein coding function and in splicing regulation. We conclude that the ABCB1 and ABCG2 variants do not confer to AED-resistance in the study population. However, ABCB1 rs1045642 increases vulnerability to epilepsy with greater tendency for MTLE-HS in south Indian ancestry from Kerala.

Circadian rhythm of homocysteine is hCLOCK genotype dependent

Homocysteine (Hcy) is known to be a prognostic marker for neurological, cardiovascular and cerebrovascular diseases and several other pathophysiological conditions. A sudden surge in Hcy can increase cardiovascular events. Hemodynamic modulations are known to be associated with individual's chronotype. Therefore, precise monitoring of Hcy is crucial for evaluating its impact on risk. The aim of the present study was to investigate the rhythmicity of Hcy under controlled dietary conditions and whether this rhythmicity is under the genetic control of circadian rhythm. Five subjects were selected from 200 Malayalam speaking healthy ethnic individuals who were screened for functionally critical variants of MTHFR and hCLOCK genes. MTHFR is the rate-limiting enzyme in the methionine cycle and critical for regulating Hcy levels while hCLOCK is a critical gene responsible in regulating the day and night cycles. Rhythmicity in Hcy levels were observed in all the subjects with a consensus on a morning nadir and an evening peak. Gender specific stratification of Hcy levels were observed among similar genotypes of MTHFR and hCLOCK genes. Variations from the conventional rhythmicity of Hcy were observed among similar genotypes of MTHFR and dissimilar hCLOCK genotypes. A reduced plasma Hcy in hCLOCK rs1801260 CC genotype individuals were observed in contrast to CT genotype individuals. The study tends to suggest that Hcy and body time are genetically interdependent and throws light on some of the previously unexplained reasons for variability in Hcy levels. A population specific variation of MTHFR and hCLOCK genes also highlights ethnicity specific risk management.

Association of interleukin-4 and interleukin-17F polymorphisms in periodontitis in Dravidian ethnicity

BACKGROUND:

Complex network of pro and anti-inflammatory cytokines are known to act in inflamed periodontal tissue. This study explores the distribution of interleukin (IL)-4 (+33 C/T) and IL-17F (7383A/G, 7488A/G) gene polymorphism in chronic and aggressive periodontitis subjects of Dravidian ethnicity.

MATERIALS AND METHODS:

This case control study consisted of 124 periodontitis individuals comprising of 63 chronic and 61 aggressive periodontitis subjects as cases, and control group consisted of 101 healthy subjects. All subjects were genotyped for IL-4 + 33C/T, IL-17F 7383A/G, 7488A/G by polymerase chain reaction amplification followed by TaqMan assay for IL-4 + 33C/T, restriction enzyme digestion and gel electrophoresis for IL-17F 7383A/G and sequencing for IL-17F 7488A/G.

RESULTS:

IL-4 + 33C/T was significantly associated with periodontitis (P < 0.05) at both allelic and genotypic level. In subgroup analysis also significant difference (P < 0.05) in allelic distribution between aggressive periodontitis and control group for loci IL-4 + 33C/T was noted. However, there was a lack of association between IL-17F 7383A/G and IL-17F 7488A/G with periodontitis and its sub-groups at both allelic and genotypic levels.

CONCLUSIONS:

In Malayalam speaking Dravidian population IL-4 + 33C/T loci appears to be an important risk factor for periodontal disease with a leaning towards aggressive periodontitis. The association between IL-17F at 7383A/G and 7488A/G loci with either chronic or an aggressive periodontitis could not be ascertained.

Relationships of Urinary Beta2- microglobulin in Neonates with Impaired Renal Function in Different Stages of Hypoxic Ischaemic Encephalopathy

Hypoxic Ischaemic Encephalopathy (HIE) is a sequelae of neonates suffering from severe perinatal asphyxia. It may also cause impaired renal function due to acute tubular necrosis followed by elevation of urinary concentration of certain low molecular weight proteins like ?2- microglobulin. This study was designed to evaluate the urinary ?2- microglobulin level in neonates with HIE patients those who have impaired renal function. This prospective case control study was carried out in the Neonatal unit of the department of Pediatrics and in the Labor ward of the department of Obstetrics and Gynecology Bangabandhu Sheik Mujib Medical University, Dhaka during the period of 1st July 2005 to 30th June 2006. This study was designed to estimate urinary ?2- micro globulin level in the asphyxiated newborn as well normal newborns to see any significant changes and to find out its relation with over all outcomes of newborns with perinatal asphyxia. In this study, 42 term newborn babies before 24 hours of age, those who failed to take spontaneous breathing within 5 minutes of the complete delivery were taken as cases and 40 healthy term newborns were taken as control. Asphyxiated newborns were divided into three groups depending on the sarnat and sarnat clinical staging of HIE. Mean±SD value of urinary ?-2- micro globulin in case group 4.1 ± 2.79 mg/l and in the control was 1.35 ± 1.08 mg/l. It shows significant (p<0.01) rise of urinary ?-2 micro globulin levels in case group. The degree of rise of urinary ?-2- micro globulin was related with the severity of HIE but blood urea and serum creatinine levels were not increased significantly in stage I and stage II except in stage III HIE patients. It was concluded from this study that raised urinary â2- microglobulin level may be related with HIE patients irrespective of clinical staging but serum creatinine and blood urea were found to be elevated only in stage III HIE patients. But to draw a conclusive evidence regarding relationship of urinary ?2 microglobulin with advance stages of HIE in neonates with impaired renal function require further large scale study. DOI: http://dx.doi.org/10.3329/bjch.v37i1.15348 BANGLADESH J CHILD HEALTH 2013; VOL 37 (1) : 22-26

Association of cytokine gene polymorphisms with oral lichen planus in Malayalam-speaking ethnicity from South India (Kerala)

Oral lichen planus (OLP) is a chronic mucocutaneous condition that affects the oral mucous membrane as well as skin. It is a chronic cell-mediated autoimmune condition where the T-cell-mediated immune response plays an important part in the pathogenesis by causing damage to basal keratinocytes in oral mucosa. Cytokine gene polymorphisms have an unquestionable role in the orchestration of the immune response, leading to different functional scenarios, which in turn influence the outcome of the disease establishment and evolution. The purpose of this study was to understand the role of these cytokine gene polymorphisms in the tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 genes with OLP in 101 individuals of Malayalam-speaking ethnicity from South India (Kerala). We further investigated the role of these polymorphisms in patients suffering from OLP with other comorbid factors. Genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism. The results demonstrate that the A allele in the TNF-α -308 polymorphism could play an important role in the susceptibility to OLP. IL-1β +3954 in OLP was associated with other comorbid factors in both allelic and genotypic combinations. However, when patients suffering from OLP were stratified to understand the involvement of other comorbid factors, we observed that the T and C alleles were independent risk factors for chronic periodontitits and diabetes mellitus. On the other hand, IL-6 -597 did not show any disease association with OLP in the study population. This study indicates that proinflammatory cytokines are an important factor in understanding the disease burden of OLP and their comorbid factors.

Predictors of recovery of ovarian function during aromatase inhibitor therapy

BACKGROUND

Aromatase inhibitors (AIs) may cause a rise in estrogen levels due to ovarian function recovery in women with clinical chemotherapy-induced ovarian failure (CIOF). We carried out a prospective registry trial to identify predictors of ovarian function recovery during AI therapy.

PATIENTS AND METHODS

Women with hormone receptor (HR)-positive breast cancer who remained amenorrheic and had hormonal levels consistent with ovarian failure after adjuvant chemotherapy were enrolled in a multi-institutional clinical trial of anastrozole. Subjects underwent frequent assessment using an ultrasensitive estradiol assay. Multivariable analysis was used to evaluate clinical and biochemical predictors of ovarian function recovery within 48 weeks.

RESULTS

Recovery of ovarian function during AI therapy was observed in 13 of 45 (28.9%) assessable subjects after a median 2.1 months (range 0.6-11.9). Median age at chemotherapy initiation was statistically significantly different between those who regained ovarian function (43 years, range 40-51) and those who remained postmenopausal (49 years, range 44-52; P < 0.0001).

CONCLUSIONS

A significant proportion of women with CIOF recover ovarian function during AI therapy, including a woman over age 50 at initiation of chemotherapy. Tamoxifen remains the standard of care for women with CIOF. If an AI is used, patients should be monitored frequently with high-quality estradiol assays. CLINICALTRIALS.GOV: NCT00555477.

Hepatitis C virus and other risk factors in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) increased in Egypt in the past years, becoming the most common cancer among men. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the known primary risk factors for HCC. This study describes the viral profile of HCC in a predominantly rural area in Egypt. We included 148 HCC cases and 148 controls from the Tanta Cancer Center and the Gharbiah Cancer Society in the Nile delta region. Serological (ELISA) and molecular (PCR) analysis for HBV and HCV infection were performed on plasma samples from each subject. Epidemiologic, environmental, and medical histories were collected by interviewing of subjects. Around 90.5% of cases and controls were from rural areas. HCV infection was high in both cases and controls (89.2% and 49.3%, for cases and controls respectively by serology). HCV was the most important HCC risk factor [OR 9.7 (95% CI: 3.3-28.0, P <0.01)], and HBV infection showed marginal tendency of increased risk [OR 5.4 (95% CI: 0.9-31.8, P <0.06)]. Ever worked in farming [OR 2.8 (95% CI: 1.1-7.2, P <0.03)] and history of cirrhosis [OR 3.6 (95% CI: 1.6-8.1, P <0.01)] or blood transfusion [OR 4.2 (95% CI: 0.99-17.8, P <0.05)] were also associated with increased HCC risk. This study in a predominantly rural area in Egypt supports previous reports from other parts of Egypt that HCV infection is the primary HCC risk factor in Egypt. Further understanding of the relationship between infection and other risk factors in the development of HCC could lead to targeted interventions for at-risk individuals.

KEYWORDS

hepatocellular carcinoma; hepatitis; rural; risk factors; Egypt.

Disease severity and radioactive iodine use for thyroid cancer

CONTEXT

Although variation in radioactive iodine (RAI) use for thyroid cancer has been demonstrated, the role of region and nonclinical correlates of use within risk groups has not been investigated.

OBJECTIVE

The objective of the study was to determine the correlates of RAI use within risk groups.

DESIGN/SETTING/PATIENTS

Use of RAI was evaluated across 9 US regions in 85 948 patients with well-differentiated thyroid cancer diagnosed between 2004 and 2008 at 986 hospitals associated with the US National Cancer Database. Cancers were then categorized as low risk (tumor size ≤ 1 cm and American Joint Committee on Cancer stage I disease), medium risk (neither low nor high-risk), and high risk (American Joint Committee on Cancer stage III or IV). Within each risk stratum, the role of region and nonclinical correlates of RAI use were evaluated using hierarchical logistic regression.

MAIN OUTCOME MEASURE

Use of RAI was measured.

RESULTS

Rates of RAI use varied across geographic regions from 49% to 66%. Regional differences persisted after controlling for patient and hospital characteristics and evaluating less vs more intensive regions within low-risk [odds ratio (OR) 0.36 (95% confidence interval [CI] 0.25-0.53)], medium-risk [OR 0.23 (95% CI 0.16-0.34)], and high-risk cancers [OR 0.30 (95% CI 0.19-0.49)]. Patterns of RAI use were similar in medium- and high-risk patients. The most nonclinical correlates of use were in low-risk patients.

CONCLUSION

Similar treatment patterns for the heterogeneous medium-risk thyroid cancer patients compared with the high-risk patients suggest more intensive management in patients with medium-risk disease. The large number of nonclinical correlates of RAI use, including region, imply controversy over indications for RAI.

Enteric fever in an HIV/AIDS patient: Atypical manifestations

Bloodstream infections with Salmonella typhi, is uncommon in human immunodeficiency virus (HIV)-infected persons. The symptoms in such patients are often non-specific and have a rather insidious onset and progression. We report a patient with sepsis and lower limb gangrene due to Salmonella typhi infection in an HIV-infected patient.

Antipsychotic drug dosage and therapeutic response in schizophrenia is influenced by ABCB1 genotypes: a study from a south Indian perspective

Aim: The conventional practice of using trial and error mode to select antipsychotic drugs in treatment of schizophrenia can result in symptom exacerbations, relapse and severe side effects, resulting in higher costs of treatment. P-glycoprotein (ABCB1) is known to regulate the concentration of antipsychotic drugs in the brain. Variable expressivity based on polymorphism in the gene ABCB1 may reflect on the drug response and its relationship to dosage. Materials & methods: All antipsychotic dosages administered to patients were converted to common chlorpromazine equivalents. Response to antipsychotics was based on 50% cutoff in Brief Psychiatric Rating Scale ratings after 1-year of follow-up. Using a case–control study design, ABCB1 polymorphisms were screened in 192 individuals grouped into responders and nonresponders. Results: A strong allelic, genotypic and haplotypic association, was observed, which was predictive of good response to antipsychotics. Individuals carrying the favorable homozygous genotypes of rs1045642 and rs2032582 displayed better response with increased dosage while those carrying risk genotype manifested refractoriness on increased dosage. Conclusion: The study suggests that a priori knowledge of ABCB1 genotypes can provide a significant input into evaluating the patient’s response to medication, and minimizing redundant dosing and refractoriness.

Original submitted 14 February 2012; Revision submitted 14 May 2012