Brief constant light accelerates serotonergic re-entrainment to large shifts of the daily light/dark cycle

Brief ( approximately 2 day) constant light exposure (LL(b)) in hamsters dramatically enhances circadian phase-resetting induced by the 5-HT receptor agonist, (+/-)-2-dipropyl-amino-8-hydroxyl-1,2,3,4-tetrahydronapthalene (8-OH-DPAT) and other nonphotic stimuli. The present study was undertaken to determine if LL(b) can also amplify phase-resetting responses to endogenous 5-HT and accelerate re-entrainment to large-magnitude advance and delay shifts of the light/dark (LD) cycle. First, central serotonergic activity was increased by i.p. injection of L-tryptophan+/-the 5-HT reuptake inhibitor fluoxetine. Hamsters under LD or exposed to LL(b) received vehicle or drugs during the early morning, and phase-shifts of the locomotor activity rhythm were measured after release to constant darkness. Neither drug phase-shifted animals not exposed to LL(b) (P>0.5 vs. vehicle); however in animals receiving LL(b,)L-tryptophan with and without fluoxetine produced large phase-advance shifts (means=2.5+/-0.4 h and 2.6+/-0.2 h, respectively; both P<0.035 vs. vehicle). Next, the effects of LL(b) combined with 8-OH-DPAT or L-tryptophan+fluoxetine on serotonergic re-entrainment to 10 h phase-advance and phase-delay shifts of the LD cycle were assessed. In groups not exposed to LL(b), vehicle controls re-entrained slowly to the advance and delay shifts (means=16+/-1 and 24+/-4 days, respectively), but those treated with 8-OH-DPAT re-entrained faster (means=11+/-2 and 9+/-2 days, respectively; both P<0.05 vs. vehicle). In groups exposed to LL(b), vehicle controls re-entrained slowly to the advance and delay shifts (means=15+/-2 and 25+/-3 days, respectively); however those receiving 8-OH-DPAT rapidly re-entrained to the delay and advance shifts, with the majority (75%) requiring only 1-2 days (means=2+/-1 and 4+/-2 days, respectively; both P<0.05 vs. vehicle). Animals exposed to LL(b) and treated with L-tryptophan+fluoxetine also exhibited accelerated re-entrainment to a 10 h advance shift (mean=5+/-2 days; P<0.05 vs. vehicle). Thus through enhancing serotonergic phase-resetting, LL(b) facilitates rapid re-entrainment to large shifts of the LD cycle which offers a potential approach for treating circadian-related desynchronies.

Plasmin enhances cell surface tissue factor activity in mesothelial and endothelial cells

BACKGROUND

Mesothelial cells that line the thoracic cavity play an important role in maintaining the local balance between procoagulant and fibrinolytic activity, a role akin to the endothelial cells in blood vessels. The mechanism(s) responsible for increased tissue factor (TF) expression in mesothelial cells in response to injury are at present unclear.

OBJECTIVE

To investigate whether plasmin or thrombin, two major proteases that may be generated on the pleural surface upon injury, induce TF expression in human pleural mesothelial cells (HMC) and elucidate the underlying mechanism(s).

METHODS

Confluent monolayers of HMC and human umbilical vein endothelial cells (HUVEC) were exposed to plasmin or thrombin for varying time periods and TF expression was analyzed by measuring its activity in a factor Xa generation assay, TF antigen levels by immunoblot analysis and TF mRNA by Northern blot analysis.

RESULTS

Both plasmin and thrombin treatments increased cell surface TF activity in HMC by 3- to 4-fold. In contrast to thrombin, plasmin-induced TF activity is not dependent on the de novo synthesis of TF. In HUVEC, plasmin had a minimal effect on unperturbed HUVEC whereas it markedly increased TF activity of activated HUVEC. Plasmin treatment neither affected anionic phospholipid levels at the cell surface nor released protein disulfide isomerase, an oxidoreductase protein that was newly described to play a role in TF activation. Plasmin cleaved cell-associated TFPI.

CONCLUSION

Thrombin up-regulates TF activity in HMC through the transcriptional activation of TF whereas plasmin increases TF activity by inactivating the cell-associated TFPI by a limited proteolysis.

Vitamin E supplement use and the incidence of cardiovascular disease and all-cause mortality in the Framingham Heart Study: Does the underlying health status play a role?

BACKGROUND

Observational studies generally showed beneficial associations between supplemental vitamin E intake and cardiovascular disease (CVD) risk whereas intervention trials reported adverse effects of vitamin E supplements. We hypothesize that these discordant findings result from differing underlying health status of study participants in observational and intervention studies.

OBJECTIVE

Determine if the relation between supplemental vitamin E intake and CVD and all-cause mortality (ACM) depends on pre-existing CVD.

DESIGN

Proportional hazards regression to relate supplemental vitamin E intake to the 10-year incidence of CVD and ACM in 4270 Framingham Study participants stratified by baseline CVD status.

RESULTS

Eleven percent of participants used vitamin E supplements at baseline. In participants with pre-existing CVD, there were 28 (44%) and 20 (32%) incident cases of CVD and ACM in the vitamin E supplement users versus 249 (47%) and 202 (38%) in the non-users, respectively (CVD HR, 0.90; 95% CL, 0.60-1.32; ACM HR, 0.74; 95% CL, 0.46-1.17). In participants without pre-existing CVD, there were 51 (13%) and 47 (12%) cases of CVD and ACM in the vitamin E supplement group versus 428 (13%) and 342 (10%) in the non-vitamin E supplement group, respectively (CVD HR, 1.00; 95% CL, 0.75-1.34; ACM HR 1.20; 95% CL, 0.89-1.64).

CONCLUSION

CVD status has no apparent influence on the association of supplemental vitamin E intake and risk for CVD and ACM in this large, community-based study. Further research is needed to clarify the basis for the discrepant results between intervention and observational studies of supplemental vitamin E intake.

Identification and characterization of CFTR gene mutations in Indian CF patients

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This study was performed on Indian CF patients (n = 50) to investigate the spectrum of mutations in the CFTR gene and their association with intragenic and extragenic marker haplotypes. We report identification of 14 previously known and eight novel mutations, namely 3986-3987delC, 876-6del4, 1792InsA, L69H, S158N, Q493L, I530L and E1329Q. The frequency of delta F508 was found to be 27%. Absolute linkage between delta F508 and the KM.19-GATT-TUB9-M470V-T854T haplotype (2-2-1-1-1) predicts a relatively recent appearance of delta F508 in Indian CF patients. Low frequency of delta F508 mutation and detection of eight novel and thirteen rare mutations reflect a heterogeneous spectrum of mutations in Indian CF patients. Failure to detect mutations in 34% of alleles indicates the possible presence of gross deletions involving one or more exons or may indicate the location of the molecular defects in either the noncoding parts of the gene or in the promoter region, which warrants analysis of those regions.

Tooth size patterns in patients with hypodontia and supernumerary teeth

AIMS

Anomalies of tooth number may not be isolated conditions but may have wider associations in the development of the dentition including tooth size. This study aimed to examine links between hypodontia, supernumerary teeth and crown size, considering the effect on the development of the whole dentition and so increase understanding of the aetiology of these conditions.

METHODS AND RESULTS

The patients, who were all of European ancestry, were 60 young adults (30 males and 30 females) with hypodontia and 60 age and sex matched controls together with 60 young adults (39 males and 21 females) with supernumerary teeth and 60 age and sex matched controls. Hand measurements of mesiodistal and buccolingual dimensions were made of the teeth on dental study models using Mitutoyo electric callipers. The mean value of two measurements was used and intra-operator and inter-operator reliability determined. Patients with hypodontia had smaller teeth than the control group and this difference was statistically significant (p<0.05) for all teeth except the MD dimensions of 13, 23, 24 and 44. The difference in size was greatest for the BL dimensions in hypodontia patients. Further, the greater the number of missing teeth the smaller the tooth size. The hypodontia patients also showed higher variability in tooth dimensions than the control group. Patients with supernumerary teeth had larger teeth than the controls, with the greatest differences in the MD dimensions. In both hypodontia and supernumerary patients the differences in tooth size were generalised throughout the dentition.

CONCLUSIONS

In anomalies of tooth number the size of teeth is also involved. In patients with hypodontia and supernumerary teeth the crown size of the whole dentition is affected. These findings are compatible with a multifactorial aetiology of these conditions.

246. Developmental switches in male sex determination and spermiogenesis; importin-chromatin remodeling factor interaction

Spermatogenesis, the complex process of generating haploid sperm capable of fertilising the female gamete, requires precisely scheduled transport into the nucleus of transcription factors and chromatin remodelling factors to implement changes in nuclear gene expression, as well as genome compaction during sperm formation (spermiogenesis). This transport is mediated by members of the importin (IMP) superfamily, which display distinct expression patterns in the rodent testis, consistent with the idea that they may carry specific cargo(es) at discrete stages of testis development. A key cargo during fetal testis development is the sex determining chromatin remodelling factor SRY, whose role in the nucleus in modulating the expression of male-specific genes such as SOX9 is critically dependent on the efficiency of its nuclear import by the specific transporter IMPbeta1; specific mutations in SRY that reduce binding by IMPbeta1 result in XY female Swyer syndrome individuals. A second cargo of significance is Cdyl (Chromodomain Y chromosome-like), involved in the histone H4 hyperacetylation which precedes the replacement of histones with protamines during spermiogenesis. We recently identified IMPalpha2, together with IMPbeta1, as Cdyl’s specific nuclear transporter. Using site-directed mutagenesis to perturb Cdyl recognition by IMPalpha2, IMP/Cdyl cotransfection approaches and quantitative confocal laser miscroscopic analysis, we established that the efficiency of Cdyl nuclear import is critical to its function in facilitating histone H4 acetylation, supporting the idea that one of the specific roles of IMPalpha2 is to localise Cdyl in the nucleus of elongating spermatids. Our findings are consistent with precisely scheduled, efficient IMP-mediated nuclear import of key chromatin remodelling factors being critical to testis development, reflecting an emerging paradigm for developmental processes in general.

Hemolytic activity of aqueous extract of Livistona chinensis fruits

Livistona chinensis is used as an anticancer agent in traditional Chinese medicine. In vitro, the extracts of fruits and seeds of L. chinensis are known to possess antiangiogenic and antiproliferative activities. Here we report the presence of phenolic compounds in L. chinensis fruits which show hemolytic activity. The hemolytic activity of phenolics is limited to an acid-precipitable fraction. Further, presence of proteins and lipids abrogated the hemolytic activity indicating astringent and membrane damaging activities as mechanisms of hemolysis. In conclusion, the hemolytic activity of phenolics in L. chinensis fruits is due to astringent and membrane damaging activities.

Distribution of CCR2 polymorphism in HIV-1-infected and healthy subjects in North India

Substitution of V64I in CCR2 relates to delayed progression to AIDS and protects against HIV-1 infection. We examined the distribution of V64I in HIV-infected and healthy North Indian subjects. No significant difference in the allele or genotype distribution of CCR2 V64I polymorphism was observed, indicating that there is no association between CCR2 V64I polymorphism and susceptibility to HIV infection in North Indian population.

Preclinical modeling of a phase 0 clinical trial protocol

14058

Background: The Exploratory IND program initiated at NCI (“Phase 0”) is designed to evaluate the pharmacodynamic effects (PD) of candidate drugs at the molecular level in the clinic. Trials employ patient biopsies and surrogate tissues (e.g. PBMCs) to determine the quantitative effect of the agent on its putative target, after a minimum number of doses. The approach requires repeated biopsy of the tumor, an understanding of the time-effect window, and some knowledge of the dose level likely to cause a measurable drug effect. Methods: Prior to initiating a Phase 0 study of the PARP (PolyAdenosyl-Ribose Polymerase) inhibitor, ABT-888, we developed a pre-clinical model to mirror the clinical protocol. Colo 829 and A375 xenografts in athymic nude [nu/nu (NCr)] mice were examined for time and dose effect on PARP using a validated, quantitative PAR assay. Extracts of entire xenografts, quartered xenografts and 18 gauge needle biopsies were examined for variability of baseline and post-treatment PAR levels. Results were cross-checked with Western analysis for polyADP-Ribose (PAR)-labeled proteins in treated mice. Pharmacokinetics (PK) were modeled using plasma drug levels. Additional studies examined the influence of previous biopsy, contralateral biopsy, vehicle treatment, and general anesthesia on PAR in xenografts. Results: A single dose of ABT-888 produced a significant decrease in intracellular PAR levels that could be measured 2 to 6 hours post-dose. PAR levels and drug effect on PAR levels were not influenced by repeated needle biopsies. Variation across xenografts was random for single and bilateral xenograft animal models in the ABT-888 treated, vehicle- and topotecan-treated control groups. Animal handling and socialization appeared to elevate baseline PAR levels, which could confound analysis of study results. Conclusions: Pre-clinical modeling of a specific Phase 0 clinical protocol for drug effects and biological variability provided valuable insights into the development, refinement, and analysis of the currently-active NCI Phase 0 clinical trial of ABT-888. Animal studies were conducted in an AAALAC approved facility under an approved IACUC protocol. Funded by NCI Contract N01-CO-12400.

No significant financial relationships to disclose.

Effect of wine phenolics on cytokine-induced C-reactive protein expression

BACKGROUND

Elevation of C-reactive protein (CRP) levels in blood was recognized as one of the cardiac disease risk factors. Consumption of wine is shown to reduce the risk from heart disease and improve longevity.

OBJECTIVES

In the present study, we evaluated the effect of various wine polyphenolic compounds and several active synthetic derivatives of resveratrol on the inflammatory cytokines (IL-1beta + IL-6)-induced CRP expression in Hep3B cells.

RESULTS

Among the wine phenolics tested, quercetin and resveratrol, in a dose-dependent manner, suppressed cytokine-induced CRP expression. Two of the synthetic derivatives of resveratrol, R3 and 7b, elicited a fiftyfold higher suppressive effect compared with resveratrol. The inhibitory effects of resveratrol and its derivatives on CRP expression were at the level of mRNA production. Investigation of signaling pathways showed that the cytokines induced the phosphorylation of p38 and p44/42 MAP kinases. Inhibitors of p38 and p44/42 mitogen-activated protein kinase (MAPK) activation inhibited CRP expression, implicating the involvement of both pathways in cytokine-induced CRP expression. These data revealed a previously unrecognized role of the p44/42 MAPK signaling pathway in CRP expression. Wine polyphenolics or the synthetic compounds of resveratrol did not affect cytokine-activated phosphorylation of these MAPKs.

CONCLUSIONS

Wine phenolics inhibit CRP expression; however, to do so, they do not utilize the MAPK pathways.

14th International HLA and Immunogenetics Workshop: Report on joint study on MHC and infection

The 'MHC and Infection' study of the 14th International HLA and Immunogenetics Workshop was undertaken to evaluate the contribution of specific variants of major histocompatibility complex (MHC) and non-MHC genes that are specifically associated with higher probabilities of infection, disease severity, and progression in different populations.

14th IHIWS MHC and Infection Study: summary and conclusions

International collaborative efforts through histocompatibility workshops have helped greatly in collating useful data on interpopulation differences in genetic susceptibility to mycobacterial and viral infections. These are imperative in exploring the genetic basis of disease pathogenesis and host resistance. Because infectious diseases involve multigenic complex traits, several genetic variants contribute modifying effects on the disease but disease outcome depends on the net relative hazards of individual genetic loci taken together. Further because occurrence of genetic variants varies in a population-specific manner, it becomes even more complicated to show genetic influences across populations. For this, large study cohorts representing different ethnicities are needed. Information thus gained could lead to the development of more effective vaccine design to combat or diminish the emergence of pathogenic multidrug resistant forms.

Association of variants in theIL12Bgene with leprosy and tuberculosis

There is a great range in outcomes after mycobacterial infections, and this is probably due to individual variation in immune responses. One of the key cytokine regulators of the immune response is interleukin (IL-) 12. The IL12B gene encodes the p40 chain of both IL-12 and IL-23 and it has two major variant sites at which different alleles are associated with increased levels of gene expression and with susceptibility to a range of immune-related diseases. We hypothesized that IL12B variants associated with increased expression would be as associated with susceptibility to persistent mycobacterial infection. We tested this hypothesis by genotyping Indian subjects, having either leprosy or tuberculosis (TB), as well as ethnically matched controls. Subjects with leprosy were less likely to have the 3'UTR genotype associated with lower IL12B expression (P= 0.001). Subjects with TB were not only more likely to have the high-expressing IL12B promoter genotype (P= 0.01) but also more likely to have this in the same haplotype with the high expressing 3'UTR allele (P= 0.0009). These results suggest these infectious diseases may be improved by modulating IL-l2p40 production.

Frequency distribution of cytokine gene polymorphisms in the healthy North Indian population

The allelic and genotype frequencies corresponding to 22 single nucleotide polymorphisms (SNPs) in 13 cytokine genes interleukin (IL) 1-alpha (T/C -889), IL1-beta (C/T -511, T/C +3962), IL12 (C/A -1188), interferon-gamma (A/T UTR 5644), transforming growth factor-beta (C/T codon 10, G/C codon 25), tumour necrosis factor-alpha (G/A -308, G/A -238), IL2 (T/G -330, G/T +160), IL4 (T/G -1098, T/C -590, T/C -33), IL6 (G/C -174, G/A nt 565), IL10 (G/A -1082, C/T -819, C/A -592), IL1R (C/T pst11970), IL1RA (T/C mspa111100) and IL4RA (G/A +1902) were determined in 130 healthy North Indian subjects. All genomic typings were performed with polymerase chain reaction with sequence-specific assays. An analysis of the allelic and haplotype frequencies in the North Indian population showed a good fit with the Hardy-Weinberg equilibrium for most of the SNPs. The data can be used for anthropological comparisons, as well as for association studies with different diseases and for use in transplant situations involving acute and chronic rejection.

RBx 7796: A novel inhibitor of 5-lipoxygenase

OBJECTIVE

To evaluate the pharmacological profile of RBx 7,796, a novel 5-lipoxygenase inhibitor.

MATERIALS AND METHODS

RBx 7,796 was evaluated for 5- lipoxygenase inhibitory potential using human recombinant enzyme and profiled for selectivity against 12 and 15 lipoxygenase. RBx 7,796 was evaluated in cell based assay for inhibition of A23,187 induced LTB(4) release from isolated neutrophils. Ex vivo activity was evaluated for inhibition of A23,187 induced LTB(4) release in blood from treated rats. In vivo efficacy of RBx 7,796 was profiled in LPS induced neutrophilia model in rats and also in ovalbumin induced bronchoconstriction and airway inflammation models in guinea pigs.

RESULTS

RBx 7,796, a novel chemotype, showed competitive inhibition of 5-lipoxygenase enzyme with an IC(50) of 3.5 +/- 1.1 microM. RBx 7,796 offered >100 fold selectivity against other related enzymes - 12 and 15 lipoxygenase. RBx 7,796 inhibited release of LTB(4) from human and rat neutrophils in vitro. Upon administration to rats, RBx 7,796 inhibited A23,187 induced LTB(4) release from rat neutrophils. Upon repeated administration, dosed once daily, RBx 7,796 inhibited LPS induced neutrophil influx in rat airway. RBx 7,796 also inhibited allergen induced bronchoconstriction and eosinophil influx in guinea pig airway in a dose dependent manner.

CONCLUSION

The results suggest that RBx 7,796, a novel chemotype, is an orally efficacious inhibitor of 5-lipoxygenase enzyme that is effective against both neutrophilic and eosinophilic airway inflammation and shows potent inhibition with once daily administration.

Inhibition of oxidative stress and cytokine activity by curcumin in amelioration of endotoxin-induced experimental hepatoxicity in rodents

The present study is aimed at investigating the effect of curcumin (CMN) in salvaging endotoxin-induced hepatic dysfunction and oxidative stress in the liver of rodents. Hepatotoxicity was induced by administering lipopolysaccharide (LPS) in a single dose of 1 mg/kg intraperitoneally to the animals, which were being treated with CMN daily for 7 days. Liver enzymes serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST) and alkaline phosphatase (ALP), total bilirubin and total protein were estimated in serum. Oxidative stress in liver tissue homogenates was estimated by measuring thiobarbituric acid reactive substances (TBARS), glutathione (GSH) content and superoxide dismutase (SOD) activity. Serum and tissue nitrite was estimated using Greiss reagent and served as an indicator of NO production. A separate set of experiments was performed to estimate the effect of CMN on cytokine levels in mouse serum after LPS challenge. LPS induced a marked hepatic dysfunction evident by rise in serum levels of ALT, AST, ALP and total bilirubin (P < 0.05). TBARS levels were significantly increased, whereas GSH and SOD levels decreased in the liver homogenates of LPS-challenged rats. CMN administration attenuated these effects of LPS successfully. Further CMN treatment also regressed various structural changes induced by LPS in the livers of rats and decreased the levels of tumour necrosis factor-alpha and interleukin-6 in mouse plasma. In conclusion, these findings suggest that CMN attenuates LPS-induced hepatotoxicity possibly by preventing cytotoxic effects of NO, oxygen free radicals and cytokines.

Polymorphism in L-Selectin, E-Selectin and ICAM-1 Genes in Asian Indian Pediatric Patients With Celiac Disease

Celiac disease (CD) follows an autoimmune course in which both genetic and environmental factors contribute to its development. A strong association with HLA class II molecules, predominantly HLA-DQ2, has been reported in most ethnic groups with CD. The aim of this study was to determine if genetic polymorphisms in L-selectin, E-selectin, and intercellular adhesion molecule-1 (ICAM-1) have any correlation with CD. We investigated 5 mutations, namely F206L in L-selectin, S128R and L554F in E-selectin, and G241R and K469E in ICAM-1, in 37 North Indian pediatric patients with CD. A significant increase in allele frequencies of 128R of E-selectin and the associated genotype SR was observed in patients. No significant differences were observed in the F206L polymorphism of L-selectin, or the G241R and E469K polymorphisms in the ICAM-1 gene in CD. This study illustrates that selectin gene polymorphism might contribute to the genetic background of CD and invites further investigation relevant to understanding the mechanisms underlying the immunopathogenesis of this autoimmune disease.

A new method of assessing anal sphincter integrity using inverted vectormanometry

PURPOSE

Vectorgraphy as an integrated mapping of radial pressure profiles of the anal canal has been used to attempt identification of pressure-related defects with doubtful reliability since vectorgraphs bear no resemblance to endoanal ultrasound scans at similar levels in the anal canal. This study aimed to devise a technique to enable vectorgraphy to be more representative of sphincter function and integrity.

METHODS

Vectormanometry was performed in 50 patients with anorectal disorders using an Arndorfer pneumohydraulic system. "Normal" three-dimensional manometric images of each 0.5 cm of the anal sphincter were computer-generated by plotting anal pressures at rest and during squeeze radially around a central zero axis. The graphs were replotted with zero at the periphery and maximal anal pressure at the center. Both this ("inverted") and "normal" vectorgraphs were compared with endoanal ultrasound images at similar levels, assessing both internal and external anal sphincters.

RESULTS

Standard vectormanometry produced excellent pictures of pressures throughout the anal canal; the anatomy however bore no resemblance to the pictures produced by endoanal ultrasound. The inverted vectographs showed a much better correlation with endoanal ultrasound at each 0.5-mm level of the anal canal, for both squeeze pressure graphs and external sphincter correlations and for resting pressure graphs and internal sphincter correlations.

CONCLUSIONS

Accurate assessment of sphincter integrity is not possible when interpreting the vectormanometry graphs in the current format; however, inverted vectorgraphy gives good correlations with endoanal ultrasound and provides combined functional (pressure measurement) and anatomic (three-dimensional profile) information regarding the anal canal.