Drugs of abuse and addiction: A slippery slope toward liver injury

Substances of abuse induce alteration in neurobehavioral symptoms, which can lead to simultaneous exacerbation of liver injury. The biochemical changes of liver are significantly observed in the abused group of people using illicit drugs or drugs that are abused. A huge amount of work has been carried out by scientists for validation experiments using animal models to assess hepatotoxicity in cases of drugs of abuse. The risk of hepatotoxicity from these psychostimulants has been determined by different research groups. Hepatotoxicity of these drugs has been recently highlighted and isolated case reports always have been documented in relation to misuse of the drugs. These drugs induce liver toxicity on acute or chronic dose dependent process, which ultimately lead to liver damage, acute fatty infiltration, cholestatic jaundice, liver granulomas, hepatitis, liver cirrhosis etc. Considering the importance of drug-induced hepatotoxicity as a major cause of liver damage, this review emphasizes on various drugs of abuse and addiction which induce hepatotoxicity along with their mechanism of liver damage in clinical aspect as well as in vitro and in vivo approach. However, the mechanisms of drug-induced hepatotoxicity is dependent on reactive metabolite formation via metabolism, modification of covalent bonding between cellular components with drug and its metabolites, reactive oxygen species generation inside and outside of hepatocytes, activation of signal transduction pathways that alter cell death or survival mechanism, and cellular mitochondrial damage, which leads to alteration in ATP generation have been notified here. Moreover, how the cytokines are modulated by these drugs has been mentioned here.

The TNF-family ligand TL1A and its receptor DR3 promote T cell mediated allergic immunopathology by enhancing differentiation and pathogenicity of IL-9 producing T cells (HYP2P.333)

The TNF-family cytokine TL1A (Tnfsf15) costimulates T cells and type 2 innate lymphocytes (ILC2) through its receptor DR3 (Tnfrsf25). DR3-deficient mice have reduced T cell accumulation at the site of inflammation, and reduced ILC2-dependent immune responses in a number of models of autoimmune and allergic diseases. In allergic lung disease models, immunopathology and local Th2 and ILC2 accumulation is reduced in DR3 deficient mice despite normal systemic priming of Th2 responses and generation of T cells secreting IL-13 and IL-4, prompting the question of whether TL1A promotes the development of other T cell subsets that secrete cytokines to drive allergic disease. Here we find that TL1A potently promotes generation of murine T cells producing IL-9 (Th9) by signaling through DR3 in a cell-intrinsic manner. TL1A enhances Th9 differentiation through an IL-2 and STAT5-dependent mechanism, unlike the TNF-family member OX40, which promotes Th9 through IL-4 and STAT6. Th9 differentiated in the presence of TL1A are more pathogenic, and endogenous TL1A signaling through DR3 on T cells is required for maximal pathology and IL-9 production in allergic lung inflammation. Taken together, these data identify TL1A-DR3 interactions as a novel pathway that promotes Th9 differentiation and pathogenicity. TL1A may be a potential therapeutic target in diseases dependent on IL-9.

The TNF-family ligand TL1A and its receptor DR3 promote T cell-mediated allergic immunopathology by enhancing differentiation and pathogenicity of IL-9-producing T cells

The TNF family cytokine TL1A (Tnfsf15) costimulates T cells and type 2 innate lymphocytes (ILC2) through its receptor DR3 (Tnfrsf25). DR3-deficient mice have reduced T cell accumulation at the site of inflammation and reduced ILC2-dependent immune responses in a number of models of autoimmune and allergic diseases. In allergic lung disease models, immunopathology and local Th2 and ILC2 accumulation is reduced in DR3-deficient mice despite normal systemic priming of Th2 responses and generation of T cells secreting IL-13 and IL-4, prompting the question of whether TL1A promotes the development of other T cell subsets that secrete cytokines to drive allergic disease. In this study, we find that TL1A potently promotes generation of murine T cells producing IL-9 (Th9) by signaling through DR3 in a cell-intrinsic manner. TL1A enhances Th9 differentiation through an IL-2 and STAT5-dependent mechanism, unlike the TNF-family member OX40, which promotes Th9 through IL-4 and STAT6. Th9 differentiated in the presence of TL1A are more pathogenic, and endogenous TL1A signaling through DR3 on T cells is required for maximal pathology and IL-9 production in allergic lung inflammation. Taken together, these data identify TL1A-DR3 interactions as a novel pathway that promotes Th9 differentiation and pathogenicity. TL1A may be a potential therapeutic target in diseases dependent on IL-9.

Frontotemporal correlates of impulsivity and machine learning in retired professional athletes with a history of multiple concussions

The frontotemporal cortical network is associated with behaviours such as impulsivity and aggression. The health of the uncinate fasciculus (UF) that connects the orbitofrontal cortex (OFC) with the anterior temporal lobe (ATL) may be a crucial determinant of behavioural regulation. Behavioural changes can emerge after repeated concussion and thus we used MRI to examine the UF and connected gray matter as it relates to impulsivity and aggression in retired professional football players who had sustained multiple concussions. Behaviourally, athletes had faster reaction times and an increased error rate on a go/no-go task, and increased aggression and mania compared to controls. MRI revealed that the athletes had (1) cortical thinning of the ATL, (2) negative correlations of OFC thickness with aggression and task errors, indicative of impulsivity, (3) negative correlations of UF axial diffusivity with error rates and aggression, and (4) elevated resting-state functional connectivity between the ATL and OFC. Using machine learning, we found that UF diffusion imaging differentiates athletes from healthy controls with significant classifiers based on UF mean and radial diffusivity showing 79–84 % sensitivity and specificity, and 0.8 areas under the ROC curves. The spatial pattern of classifier weights revealed hot spots at the orbitofrontal and temporal ends of the UF. These data implicate the UF system in the pathological outcomes of repeated concussion as they relate to impulsive behaviour. Furthermore, a support vector machine has potential utility in the general assessment and diagnosis of brain abnormalities following concussion.

Skin exposure promotes a Th2-dependent sensitization to peanut allergens

Sensitization to foods often occurs in infancy, without a known prior oral exposure, suggesting that alternative exposure routes contribute to food allergy. Here, we tested the hypothesis that peanut proteins activate innate immune pathways in the skin that promote sensitization. We exposed mice to peanut protein extract on undamaged areas of skin and observed that repeated topical exposure to peanut allergens led to sensitization and anaphylaxis upon rechallenge. In mice, this epicutaneous peanut exposure induced sensitization to the peanut components Ara h 1 and Ara h 2, which is also observed in human peanut allergy. Both crude peanut extract and Ara h 2 alone served as adjuvants, as both induced a bystander sensitization that was similar to that induced by the atopic dermatitis-associated staphylococcal enterotoxin B. In cultured human keratinocytes and in murine skin, peanut extract directly induced cytokine expression. Moreover, topical peanut extract application induced an alteration dependent on the IL-33 receptor ST2 in skin-draining DCs, resulting in Th2 cytokine production from T cells. Together, our data support the hypothesis that peanuts are allergenic due to inherent adjuvant activity and suggest that skin exposure to food allergens contributes to sensitization to foods in early life.

Performance evaluation of a dynamic telepathology system (Panoptiq™) in the morphologic assessment of peripheral blood film abnormalities

INTRODUCTION

The study evaluated the performance of a dynamic imaging telepathology system (Panoptiq(™) ) as a diagnostic aid to the identification of peripheral blood film (PBF) abnormalities.

METHODS

The study assumed a laboratory personnel working in a clinical laboratory were operating the telepathology system to seek diagnostic opinion from an external consulting hematopathologist. The study examined 100 blood films, encompassing 23 different hematological diseases, reactive or normal cases.

RESULTS

The study revealed that with real-time image transmission in live scanning mode of operation, the telepathology system was able to aid reviewers in achieving excellent accuracy, that is correct interpretation of morphologic abnormalities obtained in 83/84 of the hematologic diseases and 12/12 of the reactive/normal conditions (Sensitivity: 0.99; Specificity: 1.00). In contrast, when only saved static images in digital capture mode of operation were reviewed remotely, interpretative omissions occurred in 8/84 of the hematologic diseases and 0/12 of the reactive/normal conditions (Sensitivity: 0.91; Specificity: 1.00). It is hypothesized that real-time operator-reviewer communication during live scanning played an important role in the identification of key morphologic abnormalities for review.

CONCLUSION

Our study showed the Panoptiq system can be adopted reliably as a dynamic telepathology tool in aiding community laboratories in the triage of PBF cases for external diagnostic consultation.

The TNF family member TL1A promotes Th9 differentiation and Th9-mediated immunopathology (LYM3P.733)

The TNF family cytokine TL1A (Tnfsf15) costimulates T cells through its receptor DR3 (Tnfrsf25). Currently known effects of TL1A on T cell differentiation or systemic immune responses cannot account for the resistance of Tnfrsf25-/- mice to diverse animal models of autoimmune and allergic inflammation. IL-9 is a cytokine that promotes inflammatory and allergic immune responses and is expressed by a distinct subset of T cells early after T cell activation or restimulation. We have found that TL1A potently promotes generation of T cells producing IL-9 (Th9) by signaling through DR3 in a cell-intrinsic manner. Unlike the TNF family member OX40 ligand, TL1A increases Th9 differentiation independently of STAT6 and the TNF-signaling adaptor TRAF6. Instead, TL1A affects Th9 differentiation through enhancing IL-2-dependent STAT5 activation and allowing increased binding to the IL-9 promoter. In two models of allergic asthma, we demonstrate that Tnfrsf25-/- mice have reduced disease severity accompanied by fewer IL-9 producing T cells in the lung. In addition to promoting Th9 differentiation, we find that TL1A enhances pathogenicity in Th9 transfer models of both uveitis and allergic asthma, where endogenous TL1A signaling is required for maximal pathology and IL-9 production at the site of inflammation. Taken together, these data identify TL1A as a novel cytokine that promotes Th9 differentiation and pathogenicity and as a possible therapeutic target in diseases dependent on IL-9.

Potential contribution of monoamine oxidase a gene variants in ADHD and behavioral co-morbidities: scenario in eastern Indian probands

Attention deficit hyperactivity disorder (ADHD) is the most frequently diagnosed behavioral disorder in children with a high frequency of co-morbid conditions like conduct disorder (CD) and oppositional defiant disorder (ODD). These traits are controlled by neurotransmitters like dopamine, serotonin and norepinephrine. Monoamine oxidase A (MAOA), a mitochondrial enzyme involved in the degradation of amines, has been reported to be associated with aggression, impulsivity, depression, and mood changes. We hypothesized that MAOA can have a potential role in ADHD associated CD/ODD and analyzed 24 markers in a group of Indo-Caucasoid subjects. ADHD probands and controls (N = 150 each) matched for ethnicity and gender were recruited following the Diagnostic and Statistical Manual for Mental Disorders-IV. Appropriate scales were used for measuring CD and ODD traits. Markers were genotyped by PCR-based methods and data obtained analyzed using the Cocaphase program under UNPHASED. Only eight markers were found to be polymorphic. rs6323 "G" allele showed higher frequencies in ADHD (P = 0.0023), ADHD + CD (P = 0.03) and ADHD + ODD (P = 0.01) as compared to controls. Haplotype analysis revealed statistically significant difference for three haplotypes in ADHD cases (P < 0.02). Statistically significant differences were also noticed for haplotypes in ADHD + CD and ADHD + ODD cases (P < 0.01). LD analysis showed significant variation in different groups. Multidimensionality reduction analysis showed independent as well as interactive effects of markers. Genotypes showed correlation with behavioral problems in ADHD and ADHD + CD. We interpret that MAOA gene variants may contribute to the etiology of ADHD as well as associated co-morbid CD and ODD in this ethnic group.

Th9 cell development requires a BATF-regulated transcriptional network

T helper 9 (Th9) cells are specialized for the production of IL-9, promote allergic inflammation in mice, and are associated with allergic disease in humans. It has not been determined whether Th9 cells express a characteristic transcriptional signature. In this study, we performed microarray analysis to identify genes enriched in Th9 cells compared with other Th subsets. This analysis defined a transcriptional regulatory network required for the expression of a subset of Th9-enriched genes. The activator protein 1 (AP1) family transcription factor BATF (B cell, activating transcription factor–like) was among the genes enriched in Th9 cells and was required for the expression of IL-9 and other Th9-associated genes in both human and mouse T cells. The expression of BATF was increased in Th9 cultures derived from atopic infants compared with Th9 cultures from control infants. T cells deficient in BATF expression had a diminished capacity to promote allergic inflammation compared with wild-type controls. Moreover, mouse Th9 cells ectopically expressing BATF were more efficient at promoting allergic inflammation than control transduced cells. These data indicate that BATF is a central regulator of the Th9 phenotype and contributes to the development of allergic inflammation.

Exchange bias of the interface spin system at the Fe/MgO interface

The ferromagnet/oxide interface is key to developing emerging multiferroic and spintronic technologies with new functionality. Here we probe the Fe/MgO interface magnetization, and identify a new exchange bias phenomenon manifested only in the interface spin system, and not in the bulk. The interface magnetization exhibits a pronounced exchange bias, and the hysteresis loop is shifted entirely to one side of the zero field axis. However, the bulk magnetization does not, in marked contrast to typical systems where exchange bias is manifested in the net magnetization. This reveals the existence of an antiferromagnetic exchange pinning layer at the interface, identified here as FeO patches that exist even for a nominally 'clean' interface. These results demonstrate that atomic moments at the interface are non-collinear with the bulk magnetization, and therefore may affect the net anisotropy or serve as spin scattering sites. We control the exchange bias magnitude by varying the interface oxygen concentration and Fe-O bonding.

A transcription factor network in Th9 cells (P1229)

Th9 cells are the most recent addition to the spectrum of T helper cell subsets that differentiate in the presence of TGF-β and IL-4. Th9 cells promote allergic inflammation, anti-tumor immunity, and may contribute to the regulation of auto inflammatory disease. Whether Th9 cells express a characteristic transcriptional signature has not been determined. To define the identity of Th9 cells, we performed a microarray analysis and identified 629 genes enriched in Th9 cells compared to Th2 and Treg cells. Of these genes, we chose a panel of 14 genes based on potential relatedness to Th9 function, and confirmed Th9-enriched expression in a larger panel of T helper subsets using quantitative PCR. The Th9 enriched genes encoded transcription factors including Erg, Maf, Ahr and Crem, and surface receptors including Il17rb, Ccr4 and Ccr8. Using mice deficient for the transcription factors that promote Th9 development including STAT6, IRF4 and PU.1, we distinguished the impact of each factor on this subset of genes. Thus our data indicates that Th9 cells have an identifiable transcriptional signature, and we have defined a transcription factor network that regulates Th9 gene expression.

Risk and outcome of multidrug-resistant tuberculosis: vitamin D receptor polymorphisms and serum 25(OH)D

SETTING

All India Institute of Medical Sciences and Rajan Babu Institute of Pulmonary Medicine and Tuberculosis, New Delhi, India.

OBJECTIVE

To investigate the association of vitamin D receptor (VDR) polymorphisms and serum 25(OH)D with susceptibility to, and response to treatment of, multidrug-resistant tuberculosis (MDR-TB) in comparison with drug-susceptible pulmonary TB (DS-PTB) and healthy controls.

DESIGN

Cross-sectional study.

METHODS

A total of 897 participants from northern India were consecutively enrolled into three groups (MDR-TB 354, DS-PTB 338, controls 205). Genotypic and allelic frequencies of FokI, BsmI and TaqI VDR polymorphisms, and serum 25(OH)D, calcium and intact parathyroid hormone were measured in all participants. In those with active TB, disease severity, time to sputum smear and culture conversion were correlated with VDR genotype and biochemical parameters.

RESULTS

FokI Ff genotype and TaqI t allele correlated positively with MDR-TB; Ff genotype and f allele of FokI frequency were higher in both TB groups. BsmI Bb genotype correlated inversely with MDR-TB. Serum 25(OH)D concentrations were significantly lowest in MDR-TB, correlating inversely with time to sputum smear conversion.

CONCLUSIONS

VDR gene polymorphisms and hypovitaminosis D may predispose to MDR-TB. Lower serum 25(OH)D may increase time to MDR-TB sputum smear negativity.

Gcn5 is required for PU.1-dependent IL-9 induction in Th9 cells

Naive CD4+ T cells differentiate into various effector Th subsets depending on the Ags and cytokine microenvironment they encounter. IL-9-secreting Th9 cells are the most recent Th subset to be described. PU.1, one of the transcription factors required for the development of Th9 cells, binds to the Il9 gene. In this study, we show that PU.1 increases histone acetylation at the Il9 locus through direct interactions with histone acetyltransferases. In the absence of PU.1, there is decreased association of Gcn5 and p300/CBP associated factor and increased association of histone deacetylases at the Il9 locus in Th9 cells. Inhibition of histone deacetylase activity augments PU.1-dependent IL-9 production. PU.1 forms a complex with Gcn5, and inhibition of the expression of Gcn5 results in reduced IL-9 production. Moreover, the effects of Gcn5 on IL-9 production are specific as the production of IL-10 and IL-21, two additional cytokines produced by Th9 cells, is not altered after decreased Gcn5 expression. Together, these data define a PU.1-dependent mechanism for altered histone acetylation and expression of the Il9 locus in Th9 cells.

Physicians' attitudes towards self-treatment of latent tuberculosis

We conducted a cross-sectional study to assess physicians' attitudes towards self-treatment of latent tuberculosis infection (LTBI) based on real-time responses related to actual purified protein derivative (PPD) results, in addition to using hypothetical situations for those who were PPD-negative. We also obtained information on physicians' recommendations for their patients to treat this condition. Although the physicians claimed to recommend optimal treatment to their patients, the majority of them had different attitudes when considering treatment for themselves. There appears to be a discrepancy between physicians' attitudes to self-treatment and their management of patients with LTBI.

STAT6-dependent regulation of Th9 development

Th cell effector subsets develop in response to specific cytokine environments. The development of a particular cytokine-secreting pattern requires an integration of signals that may promote the development of opposing pathways. A recent example of this paradigm is the IL-9-secreting Th9 cell that develops in response to TGF-β and IL-4, cytokines that, in isolation, promote the development of inducible regulatory T cells and Th2 cells, respectively. To determine how the balance of these factors results in priming for IL-9 secretion, we examined the effects of each pathway on transcription factors that regulate Th cell differentiation. We demonstrated that TGF-β induces the PU.1-encoding Sfpi1 locus and that this is independent of IL-4-induced STAT6 activation. IL-4-activated STAT6 is required for repressing the expression of T-bet and Foxp3 in Th9 cells, transcription factors that inhibit IL-9 production, and STAT6 is required for the induction of IRF4, which promotes Th9 development. These data established a transcription factor network that regulates IL-9 and demonstrated how combinations of cytokine signals generate cytokine-secreting potential by altering the expression of a panel of transcription factors.

A brief history of IL-9

IL-9 was first described in the late 1980s as a member of a growing number of cytokines that had pleiotropic functions in the immune system. Although many biological functions have been attributed to IL-9, it remains an understudied cytokine. A resurgence of interest in IL-9 has been spurred by recent work demonstrating a role for IL-9 in regulating inflammatory immunity and defining the transcription factors that activate the Il9 gene in cells that most efficiently produce IL-9. In this review, we summarize the characterization of IL-9 biological activities, highlight roles for the cytokine that are clearly defined, and outline questions regarding IL-9 functions that still require further exploration.

PU.1 regulates chromatin modifications of the Il9 gene in Th9 cells (57.5)

IL-9-secreting Th9 cells are generated when naïve CD4+ T cells are cultured with IL-4 and TGF-β. The transcription factor, PU.1 is required for the development of Th9 cells. The expression of PU.1, which is abundantly expressed in Th9 cells, is dependent on TGF-β dose. Dose dependent increase in TGF-β leads to a concomitant increase in PU.1 expression and IL-9 production. Ectopic expression of PU.1 can convert Th2 cells to Th9 phenotype and enhance IL-9 production from Th9 cells. The DNA binding domain and the transactivation domains of PU.1 are required for PU.1 to activate Il9, suggesting that as it binds Il9, it recruits other factors to mediate gene activation. We hypothesized that PU.1 recruits specific chromatin modifying enzymes to the Il9 locus. H3 acetylation is decreased in PU.1-deficient Th9 cells on both the Il9 promoter and a second conserved non-coding sequence immediately after 3’ of the Il9 gene. H3K9/18 acetylation is also diminished in PU.1-deficient Th9 cells while H4 acetylation is not altered by PU.1-deficiency demonstrating specific PU.1-mediated histone modifications correlating with Il9 transcription. Overall these results indicate that PU.1 promotes expression of IL-9 by modifying specific histones at the Il9 locus.

The transcription factor STAT3 is required for T helper 2 cell development

Signal transducer and activator of transcription (STAT) family members direct the differentiation of T helper cells, with specific STAT proteins promoting distinct effector subsets. STAT6 is required for the development of T helper 2 (Th2) cells, whereas STAT3 promotes differentiation of Th17 and follicular helper T cell subsets. We demonstrated that STAT3 was also activated during Th2 cell development and was required for the expression of Th2 cell-associated cytokines and transcription factors. STAT3 bound directly to Th2 cell-associated gene loci and was required for the ability of STAT6 to bind target genes. In vivo, STAT3 deficiency in T cells eliminated the allergic inflammation in mice sensitized and challenged with ovalbumin or transgenic for constitutively active STAT6. Thus, STAT3 cooperates with STAT6 in promoting Th2 cell development. These results demonstrate that differentiating T helper cells integrate multiple STAT protein signals during Th2 cell development.

Myogenic activity in autoregulation during low frequency oscillations

Lower body negative pressure (LBNP) was applied in eight human subjects to trigger low frequency oscillations in order to study the nature of functional coupling between the hemodynamic and autonomic nervous systems, with particular focus on how the myogenic response fits within this coupling. To this end muscle sympathetic nerve activity (MSNA), mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) were measured at baseline and during LBNP and were then examined in both the time and frequency domains. At the height of low frequency oscillations (~0.1Hz) there was a strong coupling between all the five indices, marked by perfect alignment of their oscillatory frequencies. Results in the time domain show that a fall in MAP is followed by a fall in TPR at 1.58s SD 0.69), a rise in heart rate at 2.64s (SD 0.98), a rise in cardiac output at 3.72s (SD 0.60), a peak in MSNA at 5.71s (SD 1.27) and, finally, a rise in TPR at 7.13s (SD 1.02). A possible interpretation of the latter is that a drop in MAP first triggers a drop in TPR via a myogenic response before the expected rise in TPR via a rise in MSNA. In other words, following a drop in arterial pressure, myogenic response controls vessel diameter before this control is taken over by MSNA. These findings provide a possible resolution of a longstanding conceptual argument against attributing a significant role for the myogenic response in blood flow autoregulation.

PU.1 expression in T cells is required for the development of IL-9 producing T cells in allergic inflammation (141.14)

The well documented Ets family transcription factor, PU.1 is an important regulator of mast cell, granulocyte and B cell development. Previous studies from our laboratory have identified a novel role for PU.1 in regulating Th2 cell cytokine expression. To further define a role for PU.1 in the development of allergic inflammation in vivo, we studied the development of allergic airway inflammation in mice with a conditional deletion of PU.1 in T cells. Despite the development of normal Th2-responses in the periphery, PU.1 deficient T cells have attenuated allergic inflammation in the lung as compared to wild type mice. To elucidate the mechanism for decreased inflammation in the lung, analysis of cytokines and chemokines from mice that had T cells lacking PU.1, demonstrated significantly decreased levels of IL-9 in the bronchoalveolar lavage fluid concomitant with a significant reduction in the pro-allergic chemokines, CCL17 & CCL22 in lung tissue. We identified PU.1 as a factor that promotes the Th9 phenotype by both repressing Th2 cytokine production and increasing IL-9 production. PU.1 was required for normal generation of IL-9 secreting T cells in vitro and ectopic expression of PU.1 increased IL-9 and chemokine production from Th9 cultures. Together, these data suggest a critical role for PU.1 in generating the Th9 phenotype and in the development of allergic inflammation.

Impaired development of human Th1 cells in patients with deficient expression of STAT4 (46.14)

IL-12 activates STAT4, which is a critical regulator of inflammation and Th1 lineage development in murine systems. The requirement for STAT4 in the generation of human Th1 cells has not been examined thoroughly. Expression of the Th1 signature markers IFNγ, IL-12Rβ2, TNFα, and CXCR3 is greatly reduced in Th1 cultures of CD4 T cells isolated from Non-Hodgkin's Lymphoma patients following autologous stem cell transplant, which have acquired STAT4 deficiency, compared to control Th1 cultures. T-bet expression is not affected whereas IL-4 and IL-5 production is increased in patient Th1 cultures. STAT4 deficiency does not result in defects in the development of Th2 cells. Reconstitution of STAT4 in patient T cells allowed recovery of Th1 signature markers IFNγ, IL-12Rβ2, and CXCR3. In contrast, ectopic expression of IL-12Rβ2 in patient Th1 cells, which was also decreased with acquired STAT4-deficiency, did not rescue STAT4 expression, though it did increase IFNγ production to levels intermediate between control and patient samples. These results demonstrate that as in murine systems, STAT4 is required for optimal human Th1 lineage development.

Presence of 25(OH) D deficiency in a rural North Indian village despite abundant sunshine

BACKGROUND AND OBJECTIVE

Several studies have shown wide prevalence of vitamin D deficiency with serum 25(OH)D <49.9 nmol/L in urban Indians related to their poor sunshine exposure and skin pigmentation. However, there is limited information in rural Indians. We hypothesized presence of higher 25(OH)D in rural subjects as compared to urban because of farming related abundant sunshine exposure.

DESIGN AND METHODS

We assessed serum 25(OH)D levels in residents of a North Indian village with 200 families, located 90 km East of Delhi during February (winter). Fifty seven subjects (32 males and 25 females) from 50 families consented for the study.

RESULTS

The mean 25(OH)D values of all subjects in the rural area was 36.4 +/- 22.5 nmol/l/L. Males had significantly higher 25(OH)D values than females. When compared to urban subjects, the mean 25(OH)D value of rural males and females was six and three folds higher, respectively. However even with five hours of daily sunshine exposure only 31.5% had serum 25(OH)D levels > or = 50 nmol/L.

CONCLUSIONS

Thus, with longer sunshine exposure subjects residing in rural area had better mean 25(OH)D values than that of urbans. However, 70% of them were still vitamin D deficient. These facts indicate the need for the countrywide vitamin D food fortification program irrespective of rural or urban setting.

Prevalence & potential significance of vitamin D deficiency in Asian Indians

Studies from our center and other parts of India have drawn attention towards wide prevalence of vitamin D deficiency (VDD) in our country. VDD has been reported in all age groups including toddlers, school children, pregnant women and their neonates and adult males and females residing in rural and urban India. We reviewed implications of VDD in our population based on the preliminary data available from Indian studies on skeletal health. Besides, a brief review is made on the importance of VDD in various other disorders prevalent in equivalent proportions among Indians such as type 2 diabetes mellitus (DM), cardiovascular diseases (CVD), immune competence including relation to tuberculosis, malignancy and osteoarthritis. Data from the West have also associated VDD with increased prevalence of type 2DM, CVD, autoimmune disorders, tuberculosis, prostate, breast and colon malignancy and osteoarthritis. Such association has not been studied to date in our country. Overall results of various studies conducted to date in urban and rural Indians indicate that widely prevalent VDD is functionally relevant to skeletal health including osteomalacia and rickets. However, there is a need to explore its association with osteoporosis related fractures and various other non skeletal disorders linked with VDD.

The presence of anticardiolipin antibodies in adults may be influenced by infections in infancy

OBJECTIVES

There has been limited success defining environmental factors important in the development of antiphospholipid (Hughes) syndrome (APS). Recent work suggests that the perinatal environment may be important in the development of other autoimmune diseases. We measured anticardiolipin antibodies (aCL) in a general population with well-defined early lives to see whether fetal and infant growth and infections were associated with aCL positivity in adult life.

METHODS

aCLs were measured using an ELISA in 1384 individuals from the Hertfordshire cohort study. We investigated associations between the presence of aCL and early growth and infectious exposure in infancy in men and women.

RESULTS

ELISA positive aCL (IgM and IgG) was present in 22 (3%) men and 15 (2%) women. Using the highest octile of aCL results, in men higher birth weight (per lb of birth weight: OR 1.18, 95% CI 1.02-1.36, P = 0.02) and diarrhoeal infection in the first year of life (OR 2.55, 95% CI 1.10, 5.92, P = 0.03) were associated with an increased likelihood of being aCL positive. In women, diarrhoeal infection in the first year of life was also associated with an increased likelihood of aCL positivity (OR 2.23, 95% CI 1.01, 4.91, P = 0.05). For IgG titre in men, significant relationships were found with sharing a bedroom (regression coefficient 1.13; 95% CI 1.05, 1.22; P = 0.02) and diarrhoea in the first year (coefficient 1.25; 95% CI 1.00, 1.56; P = 0.05).

CONCLUSION

A developing immune system when exposed to the infectious environment may influence the likelihood of producing aCL in adult life.

Role of virulence plasmid of Aeromonas hydrophila in the pathogenesis of ulcerative disease syndrome in Clarias batrachus

Pathogenic Aeromonas hydrophila (strain VB21), a multiple-drug resistance strain contains a plasmid of about 21 kb. After curing of plasmid, the isolates became sensitive to antimicrobials, to which they were earlier resistant. The cured bacteria exhibited significant alterations in their surface structure, growth profile and virulence properties, and failed to cause ulcerative disease syndrome (UDS) when injected into the Indian catfish Clarias batrachus. Routine biochemical studies revealed that the plasmid curing did not alter the biochemical properties of the bacteria. After transformation of the plasmid into cured A. hydrophila the bacterium regained its virulence properties and induced all the characteristic symptoms of UDS when injected into fish. Thus, the plasmid plays a pivotal role in the phenotype, growth and virulence of A. hydrophila and pathogenesis of aeromonad UDS.

Association and interaction of the TNF-alpha gene with other pro- and anti-inflammatory cytokine genes and HLA genes in patients with type 1 diabetes from North India

Type 1 diabetes (T1D) is a multifactorial autoimmune disorder where major histocompatibility complex (MHC) genes and the insulin-linked polymorphic region have been shown to play major roles. We report here an integrated effect of tumor necrosis factor (TNF) alpha with other cytokine genes. The TNF-alpha-308 GA and AA (high secretor) polymorphisms were significantly increased in the patients with T1D (n = 235) [P < 7 x 10(-6), odds ratio (OR) = 3.04, 95% confidence interval (CI) = 1.8-5.3] compared with the controls (n= 128). The variants of interferon-gamma (IFN-gamma) (A(+874)T), interleukin (IL)-6 (G(-174)C), IL-10 (A(-1082)G, T(-819)C, C(-592)A) and transforming growth factor (TGF) beta1 (T(cdn10)C, G(cdn25)C) did not show a significant difference between patients and controls. However, simultaneous presence of TNF-alpha-308 GA+AA along with both high and low secretor genotypes of IFN-gamma (P < 0.003) was significantly increased in patients. Simultaneous presence of TNF-alpha-308 GA + AA along with high secretor genotypes of IL-6 (P < 0.0001, OR = 2.61, 95% CI = 1.5-4.56), IL-10 (P < 0.0001, OR = 4.26, 95% CI = 1.9-10.1) and TGF-beta1 (P < 0.00004, OR = 2.8, 95% CI = 1.6-4.86) was also significantly increased in patients with T1D. Low secretor genotype of TNF-alpha-308 GG along with low secretor genotypes of IFN-gamma (P < 0.001, OR = 0.465, 95% CI = 0.28-0.77), high secretor genotypes of IL-6 (P < 0.000004, OR = 0.76, 95% CI = 0.227-0.621) and TGF-beta1 (P < 0.000006, OR = 0.336, 95% CI = 0.198-0.568) was protective. The TNF-alpha-308 G allele was in linkage disequilibrium (LD) with the human leukocyte antigen (HLA)-B*0801-DRB1*0301 haplotype, while TNF-alpha-308 A allele was in LD with the HLA-B*5001-DRB1*0301 and B*5801-DRB1*0301 haplotypes, suggesting that the effect of TNF-alpha -308 A allele is not because of its being in LD with any HLA alleles, but because of its functional role and its integrated effect with other cytokines.

Sex differences in the effect of prepubertal GALP infusion on growth, metabolism and LH secretion

The hypothalamic neuropeptide, galanin-like peptide (GALP), is known to have an effect on energy expenditure and reproduction in adult male rats, but little work has been done on prepubertal rats. We hypothesized that hypothalamic GALP is involved in physiological changes associated with the onset of puberty. To test this hypothesis, we first determined the postnatal ontogeny of GALP gene expression via in situ hybridization of developing male and female rat pups through adulthood. GALP gene expression was not observed in either male or female rat pups until after postnatal day (PND) 10 and did not reach adult-like levels until after weaning (PND25). To determine if exogenous GALP could induce the onset of puberty, PND25 male and female rats were implanted with lateral ventricular cannulas connected to an osmotic minipump that delivered either GALP or vehicle. GALP infusion significantly (p<0.05) increased body weight, food intake, and metabolic rate in male but not female rats compared to control infusion. After 2 weeks, GALP infusion had no significant effect on the onset of puberty, percent body fat, nor plasma levels of insulin, FSH or gonadal steroids in either sex; however, GALP did significantly (p<0.05) increase plasma levels of LH and leptin in male but not female rats and increased plasma growth hormone (GH) in both sexes. Our observations further demonstrate a sex difference in GALP responsiveness in prepubertal rats. These data suggest that GALP may be involved with the prepubertal increase in circulating leptin, LH, and GH resulting in an increase in metabolic rate and lean growth associated with puberty.

The autoantibody rheumatoid factor may be an independent risk factor for ischaemic heart disease in men

BACKGROUND

Subjects with rheumatoid arthritis have an increased prevalence of ischaemic heart disease (IHD). This is most likely in those people with the autoantibody rheumatoid factor (RF). RF is strongly associated with rheumatoid arthritis (RA) but is also present in up to 15% of all adults.

OBJECTIVE

To determine whether RF might identify people in a general population who also share an increased likelihood of developing IHD.

METHODS

Subjects from the Hertfordshire Cohort Study were investigated for the presence of RF. Subjects completed a questionnaire and attended a clinic where a history of IHD was recorded (ECG, coronary artery bypass grafting, Rose chest pain). Associations between the presence of RF, antinuclear antibodies (ANA), anticardiolipin antibodies (ACA) and IHD in 567 men and 589 women were investigated and compared with traditional risk factors for IHD.

RESULTS

RF was associated with an increased likelihood of IHD in men (odds ratio (OR) = 3.1, 95% CI 1.7 to 5.4, p<0.001). This increased risk could not be explained by traditional risk factors for IHD (mutually adjusted OR for RF 2.9 (95% CI 1.6 to 5.3), p<0.001). There was no significant association between RF in women or between ANA or ACA with IHD in men or women.

CONCLUSION

This work suggests that RF is an independent risk factor for IHD in the general population. It lends support to the importance of inflammation in atherosclerosis and suggests that autoimmune processes may be involved. In addition, it raises the intriguing possibility that RF may have a direct role in the pathogenesis of IHD in some subjects.

Role of vascular bed compliance in vasomotor control in human skeletal muscle

The current view of neurogenic vasomotor control in skeletal muscle is based largely on changes in vascular bed resistance. The purpose of this study was to determine to what extent vascular bed compliance may also play a role in this regulation. For this purpose, pressure waveforms (Millar and Finometer) and flow waveforms (Doppler ultrasound) were measured simultaneously in the brachial artery of seven healthy individuals during physiological manoeuvres which were expected to produce non-neurogenic changes in resistance (wrist-cuff occlusion; n = 5) or compliance (arm elevation; n = 6) of the forearm vascular bed. Vascular resistance (R) was calculated from the average flow and pressure values. A lumped Windkessel model was used to obtain vascular bed compliance (C) from these concurrently measured waveforms. Compared with baseline (3.81 +/- 1.59 ml min(-1) mmHg(-1)), wrist occlusion increased R (65 +/- 75%; P < 0.05) with minimal change in C (-15 +/- 16%; n.s.). Compared with the arm in neutral position (0.0075 +/- 0.003 ml mmHg(-1)), elevation of the arm above heart level produced a 86 +/- 41% increase in C (P < 0.05) with little change in R (-5 +/- 11%). In addition, neurogenic changes were assessed during lower body negative pressure (LBNP) and a cold pressor test (CPT; n = 7). Lower body negative pressure induced a 29 +/- 24% increase in R and a 26 +/- 12% decrease in C (both P < 0.05). The CPT induced no consistent change in R but a 22 +/- 7% reduction in C (P < 0.05). It was concluded that vascular bed compliance is an independent variable which should be considered along with vascular bed resistance in the mechanics of vasomotor regulation in skeletal muscle.

Oxidized phosphatidylcholine is a marker for neuroinflammation in multiple sclerosis brain

Multiple sclerosis (MS) is a common autoimmune neurodegenerative disease of unknown cause, which results in inflammation and plaques of demyelination in brain and eventual axonal degeneration. We report the novel presence of oxidized phosphatidylcholine [1-palmitoyl-2-(5'-oxo)valeryl-sn-glycero-3-phosphorylcholine (POVPC)], a lipid associated with inflammatory diseases such as atherosclerosis and lung disease, in the brain of MS patients. The OxPC epitope was detected by Western blotting with the E06 monoclonal antibody. E06-positive lipid was present in the highest amounts in MS plaques, which also showed evidence of low-molecular-weight (15-kDa) OxPC-modified protein. E06 reactivity did not change with post-mortem interval, and E06-positive lipids were largely absent from control tissue. We then used a second monoclonal antibody (AB1-2, which recognizes the E06/T15 idiotype and therefore detects the presence of antibody to OxPC) to show that MS brain samples were strongly positive for the 50-kDa antibody heavy chain. We also showed that isoelectric focussing of the oligoclonal IgG characteristic of MS revealed some immunoglobulin bands that Western blotted with the AB1-2 antibody. Spinal cords from mice induced to undergo experimental allergic encephalomyelitis (EAE) also showed strong AB1-2 reactivity by both immunocytochemistry and Western blot analysis. We therefore conclude that we can detect both OxPC and 15-kDa protein modified by OxPC and the antibody to the antibody to OxPC (antiidiotype) in pathological tissue and suggest that this could play a role in the progression of MS.

Extensive DNA methylation in normal colorectal mucosa in hyperplastic polyposis

BACKGROUND

Hyperplastic polyposis of the colorectum is a precancerous condition that has been linked with DNA methylation. The polyps in this condition have been distinguished from typical small hyperplastic polyps and renamed sessile serrated adenomas. Sessile serrated adenomas also occur sporadically and appear to be indistinguishable from their counterparts in hyperplastic polyposis.

AIMS AND METHODS

The existence of distinguishing molecular features was explored in a series of serrated polyps and matched normal mucosa from patients with and without hyperplastic polyposis by assessing mutation of BRAF, DNA methylation in 14 markers (MINTs 1, 2 and 31, p16, MGMT, MLH1, RASSF1, RASSF2, NORE1 (RASSF5), RKIP, MST1, DAPK, FAS, and CHFR), and immunoexpression of MLH1.

RESULTS

There was more extensive methylation in sessile serrated adenomas from subjects with hyperplastic polyposis (p<0.0001). A more clearcut difference in patients with hyperplastic polyposis was the finding of extensive DNA methylation in normal mucosa from the proximal colon.

CONCLUSIONS

A genetic predisposition may underlie at least some forms of hyperplastic polyposis in which the earliest manifestation may be hypermethylation of multiple gene promoters in normal colorectal mucosa. Additionally, some of the heterogeneity within hyperplastic polyposis may be explained by different propensities for MLH1 inactivation within polyps.

Familial pachydermoperiostosis in association with protein-losing enteropathy

In this report we describe a rare association of pachydermoperiostosis with protein-losing enteropathy (PLE) in a family of three brothers. The first brother had the complete form of pachydermoperiostosis along with PLE. The second brother had the 'forme fruste' of pachydermoperiostosis, with minimal skin changes, bony abnormalities and PLE, which was due to intestinal lymphangiectasia. The third brother had an incomplete form of pachydermoperiostosis without evidence of PLE. To our knowledge, the association of pachydermoperiostosis with PLE due to intestinal lymphangiectasia has not been reported previously.

Protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene R620W variant and sporadic idiopathic hypoparathyroidism in Asian Indians

Recently, a gain of function variant C1858T of the lymphoid-specific protein tyrosine phosphatase non-receptor (LYP, PTPN22) gene has been reported to be associated with several autoimmune disorders including Graves' disease, type 1 diabetes, rheumatoid arthritis and vitiligo. The present study was carried out in 80 patients with sporadic idiopathic hypoparathyroidism (SIH) [43 males and 37 females, mean +/- SD age and duration of symptoms 32.5 +/- 14.1 years and 6.7 +/- 7.2 years (range 1 day to 35 years), respectively] and 193 healthy controls (male : female ratio 91:102, mean +/- SD age, 43.1 +/- 11.6 years) to assess association of 1858T allele with the disease. Polymerase chain reaction-restriction fragment length polymorphism analysis was performed to genotype C1858T variant. The frequency of occurrence of 1858T allele was 4/160 (2.5%) in SIH and 5/386 (1.3%) in the control alleles (odds ratio 1.95, 95% CI 0.51-7.37). Thus, the present study reveals that 1858T allele is rare (1.3%) in Asian Indians. The trend of higher prevalence of 1858T allele in patients with SIH needs to be studied further in other population with higher rate of the allele to support the autoimmune basis of the disease.

Promoter region -318 C/ T and -1661 A/G CTLA-4 single nucleotide polymorphisms and type 1 diabetes in North Indians

Single nucleotide polymorphisms (SNPs) of the CTLA-4 gene have been associated with manifestation of type 1 diabetes in several populations. We assessed the association of five SNPs present in the CTLA-4 gene [-318C/T, -1661A/G and -1722C/T in the promoter region, +49A/G in exon 1 and CT60 in the 3' untranslated region (UTR) region] with type 1 diabetes in North Indian subjects. Genotyping was performed in the patients (n = 130) and the healthy control (n = 180) subjects by polymerase chain reaction-fragment length polymorphism analysis using MseI, BbvI, BstEII and NcoI restriction endonucleases for the -318, -1661, -1722, +49 and CT60 SNPs, respectively. The frequency of G alleles at -1661 locus was significantly higher in the patient group compared with the control subjects. Although the frequency of T alleles at -318 SNP was significantly higher in patients with type 1 diabetes compared with the controls, it did not remain significant after Bonferroni correction for the number of alleles tested. The frequencies of C/T alleles and genotypes at -1722C/T and G allele at +49A/G and CT60 SNPs were not significantly different between the patient and the control groups. Of the various possible haplotypes constructed using the five genetic loci tested (-318, -1661, -1722, +49, CT60), the frequency of 'TGTAG' haplotype was significantly higher in the patients when compared with the controls. The results of the present study indicate that the presence of G allele at -1661 locus at the CTLA-4 gene (IDDM12 locus) is associated with increased susceptibility to type 1 diabetes in North Indians, whereas A allele is protective.

Polymorphisms at +49A/G and CT60 sites in the 3' UTR of the CTLA-4 gene and APECED-related AIRE gene mutations analysis in sporadic idiopathic hypoparathyroidism

Autoimmune diseases such as Graves' disease and type 1 diabetes have been linked with +49A/G and CT60 single nucleotide polymorphisms (SNPs) in the 3' UTR of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene. Both these SNPs are functionally relevant and linked with T-lymphocyte activation. Hypoparathyroidism is seen in 70% of patients with autoimmune polyendocrinopathy candidiasis ectodermal dystrophy syndrome (APECED). Although calcium sensing receptor autoantibodies (CaSRAb) and generalized activation of T lymphocytes are reported among patients with sporadic idiopathic hypoparathyroidism (SIH), CTLA-4 gene SNPs and APECED-related autoimmune regulator (AIRE) gene mutations have not been assessed in them. We studied lead CTLA-4 gene SNPs and APECED-related AIRE gene mutations in 73 patients with SIH and 114 healthy subjects. The CTLA-4 gene SNPs +49A/G in exon 1, CT60A/G in 3' UTR and -318C/T in the promoter region were genotyped by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) using BstEII, NcoI and MseI endonucleases, respectively. The APECED-related AIRE gene mutations, which is R257X (Finn-major) in exon 6, 4-bp insertion and 13-bp deletion in exon 8, and Iranian Jews population 'Y85C' mutation in exon 2, were studied by PCR-RFLP (Taq-I), PCR and nucleotide sequencing, respectively. CaSRAb were studied by immunoblotting. The frequencies of CTLA-4 A/A(49), A/G(49) and G/G(49) genotypes in the patients (47.9%, 38.4% and 13.7%) and controls (45.6%, 39.5% and 14.9%, respectively) and the frequencies of CT60 A/A, A/G, and G/G genotypes in the patient (42.4%, 37.0% and 20.6%) and the control (38.6%, 40.4% and 21.0%, respectively) groups were not significantly different. The frequencies of various haplotypes including genetic loci +49A/G and CT60 and frequencies of G alleles at these positions were comparable between patient and the control groups and its presence did not correlate with clinical and biochemical indices of the disease. None of the patients had APECED-related AIRE gene mutations. Lack of significant difference in the pattern of CTLA-4 A/G(49) and/or CT60A/G genotypes and absence of common APECED syndrome-related AIRE gene mutations among patients and controls suggest that these sites do not play a role in the development of the SIH.

Can propofol precipitate pancreatitis in patients with Cushing's syndrome?

We encountered two cases of acute pancreatitis in patients with Cushing's disease following transnasal transsphenoidal hypophysectomy. In both cases propofol was used in bolus doses, and is thought to be the probable factor for its development. Since elevated cortisol levels in Cushing's disease poses a threat for pancreatitis, there is a possibility that patients with Cushing's disease might be more prone to acute pancreatitis following propofol administration. Anaesthesiologists and physicians dealing with the management of Cushing's disease need to be aware of this possibility.