Dynamic changes in dna methylation status in peripheral blood Mononuclear cells following an acute bout of exercise: Potential impact of exercise-induced elevations in interleukin-6 concentration.

The aim of the present study was to examine the relationship between interleukin (IL)-6 concentrations and DNA methylation in the peripheral blood mononuclear cells (PBMCs) of trained runners after a bout of prolonged, strenuous exercise. Eight healthy trained males completed a treadmill run at 60% vVO(2max) for 120 min followed by a 5-km time trial in a fasted condition. Whole blood samples were taken prior to, immediately before and 24 h following exercise. From these samples, PBMCs were isolated for analysis and plasma IL-6 concentrations were measured. The methylation status of DNA extracted from PBMCs was analysed using the Illumina 27k methylation beadchip platform. Global DNA methylation status was unaltered immediately and up to 24 hours following a bout of prolonged exercise in comparison to pre-exercise. Despite no change in global DNA methylation, plasma IL-6 concentrations were significantly related to the DNA methylation status of 11 genes. Our study demonstrates that the methylome is stable, while discovering a novel link between exercise-induced increases in circulating IL-6 and the DNA methylation status of 11 individual genes. Based on our preliminary findings, the mechanisms by which changes in plasma IL-6 concentrations and DNA methylation in response to exercise interact require further study.

Polymorphisms of endotoxin pathway and endotoxin exposure: in vitro IgE synthesis and replication in a birth cohort.

BACKGROUND: Genetic variants in endotoxin signaling pathway are important in modulating the effect of environmental endotoxin on asthma and atopic phenotypes. Our objective was to determine the single nucleotide polymorphisms (SNPs) in the endotoxin signaling pathway that may influence in vitro IgE synthesis and to investigate the relationship between these variants and endotoxin exposure in relation to the development of asthma and atopy in a birth cohort. METHODS: Peripheral blood mononuclear cells from 45 children with asthma were stimulated with 2 and 200 ng/ml lipopolysaccharide in vitro and IgE was measured in the culture supernatants. Children were genotyped for 121 SNPs from 30 genes in the endotoxin signaling pathway. Variants with a dose-response IgE production in relation to lipopolysaccharide (LPS) were selected for replication in a population-based birth cohort, in which we investigated the interaction between these SNPs and endotoxin exposure in relation to airway hyper-responsiveness, wheeze, and atopic sensitization. RESULTS: Twenty-one SNPs in nine genes (CD14, TLR4, IRF3, TRAF-6, TIRAP, TRIF, IKK-1, ST-2, SOCS1) were found to modulate the effect of endotoxin on in vitro IgE synthesis, with six displaying high linkage disequilibrium. Of the remaining 15 SNPs, for seven we found significant relationships between genotype and endotoxin exposure in the genetic association study in relation to symptomatic airway hyper-responsiveness (CD14-rs2915863 and rs2569191, TRIF-rs4807000), current wheeze (ST-2-rs17639215, IKK-1-rs2230804, and TRIF-rs4807000), and atopy (CD14-rs2915863 and rs2569192, TRAF-6-rs5030411, and IKK-1-rs2230804). CONCLUSIONS: Variants in the endotoxin signaling pathway are important determinants of asthma and atopy. The genotype effect is a function of the environmental endotoxin exposure.

Multiple atopy phenotypes and their associations with asthma: similar findings from two birth cohorts.

BACKGROUND: Although atopic sensitization is one of the strongest risk factors for asthma, its relationship with asthma is poorly understood. We hypothesize that 'atopy' encompasses multiple sub-phenotypes that relate to asthma in different ways. METHODS: In two population-based birth cohorts (Manchester and Isle of Wight - IoW), we used a machine learning approach to independently cluster children into different classes of atopic sensitization in an unsupervised manner, based on skin prick and sIgE tests taken throughout childhood and adolescence. We examined the qualitative cluster properties and their relationship to asthma and lung function. RESULTS: A five-class solution best described the data in both cohorts, with striking similarity between the classes across the two populations. Compared with nonsensitized class, children in the class with sensitivity to a wide variety of allergens (~1/3 of children atopic by conventional definition) were much more likely to have asthma (aOR [95% CI0; 20.1 [10.9-40.2] in Manchester and 11.9 [7.3-19.4] in IoW). The relationship between asthma and conventional atopy was much weaker (5.5 [3.4-8.8] in Manchester and 5.8 [4.1-8.3] in IoW). In both cohorts, children in this class had significantly poorer lung function (FEV1 /FVC lower by 4.4% in Manchester and 2.6% in IoW; P < 0.001), most reactive airways, highest eNO and most hospital admissions for asthma (P < 0.001). CONCLUSIONS: By adopting a machine learning approach to longitudinal data on allergic sensitization from two independent unselected birth cohorts, we identified latent classes with strikingly similar patterns of atopic response and association with clinical outcomes, suggesting the existence of multiple atopy phenotypes.

Methylation of IL-2 promoter at birth alters the risk of asthma exacerbations during childhood.

BACKGROUND: Epigenetic modifications may have a role in asthma susceptibility. OBJECTIVE: To investigate whether epigenetic modification at birth of a CpG site necessary for the regulation of IL-2 transcription (IL-2 Site1) is associated with the development of asthma during childhood. METHODS: Methylation of IL-2 Site1 was assessed in cord blood from 303 children (225 with atopic mothers); as controls, we measured methylation of a site not important in the transcription of IL-2 (IL-2 Site7) and methylation of the LINE-1 repetitive element. Children were followed to the age of 8 years. Information on severe asthma exacerbations and hospital admissions was collected from child's primary care medical record. To account for potential confounding by bronchiolitis, we used exacerbations/hospitalizations after age 1 year as primary outcomes. RESULTS: There were 49 severe exacerbations amongst 33 children, and 22 hospital admissions amongst 11 children. The risk of asthma exacerbation increased 1.07-fold (95% CI 1.01-1.14, P = 0.03) and the risk of hospital admission increased 1.12-fold (95% CI 1.04-1.20, P = 0.002) for each one per cent increase in IL-2 Site1 methylation. Children who were admitted to hospital at any time-point had significantly higher IL-2 Site1 methylation than children not admitted to hospital (P = 0.007). There was a significant interaction between age at exacerbation (P = 0.03) or hospital admission (P = 0.02) and methylation, with the effect of methylation increasing with increasing age. Methylation of the control IL-2 Site7 or LINE-1 was not a significant predictor of asthma exacerbations/hospital admission, and we found no association between IL-2 Site1 methylation and hospital admissions for other reasons (0.99 [0.92-1.06]). Cord blood mononuclear cell phytohemagglutinin-stimulated lymphoproliferative responses decreased significantly with increasing IL-2 Site1 methylation (P < 0.001). CONCLUSIONS: Increasing methylation in cord blood of a functional CpG site in the IL-2 promoter is associated with increased likelihood of severe asthma exacerbations and hospital admissions for asthma/wheeze between ages of 2 and 8 years.

Feasibility of short message service to document bleeding episodes in children with haemophilia.

The increasing emphasis on home-based treatment for the management of children with haemophilia has meant that many of these children no longer regularly report to a medical facility. Consequently, it is difficult to monitor incidence of bleeding episodes. The aim of this study was to assess the feasibility of using a short message service (SMS) to monitor incidence of bleeding episodes in children with haemophilia. One hundred and four children with moderate and severe haemophilia A or B took part in a 1-year prospective study between 2008 and 2010. Children or their parents were asked to maintain a bleeds diary. They received a weekly SMS asking whether there had been a bleeding episode in the preceding week. Response rates were calculated. Children were followed for a total of 4839 person-weeks. SMS replies were received for 4201 weeks. Thus, the rate of follow-up was 86.8%. Median responses rates were 94.2% (IQR: 86.1-100%). Weekly SMS is a feasible reporting tool for documenting bleeding episodes in children with haemophilia. It is associated with high response rates and minimal expense and intrusion. The use of SMS could be extended to encourage compliance to prophylactic treatment, particularly in adolescents with haemophilia.

Fitness and quality of life in children with haemophilia.

Prior to the introduction of prophylactic clotting factor, children with haemophilia were discouraged from physical activity due to the risk of bleeds. Reports of children with haemophilia having lower levels of fitness and strength than their healthy peers were therefore well accepted. This study aimed to establish whether these deficits continued, and specifically, whether Australian boys with haemophilia and von Willebrand disorder had lower strength and aerobic capacity than their peers, despite widespread use of prophylaxis. Forty-four boys aged 6.1-17.0 years (mean 10.9, SD 3.2) with haemophilia A and B and von Willebrand disorder participated in the study. Fitness, strength and body mass index (BMI) measures were compared with age- and gender-matched data from a representative cohort of school children. Quality of Life was measured using the Haemo-QoL to obtain baseline measures in an Australian population. There were no statistically significant or clinically important differences in aerobic fitness or BMI between the boys with haemophilia and controls in any age category. Boys with haemophilia in Years 4, 6 and 10 had greater strength than their peers. Australian boys with bleeding disorders do not have impaired aerobic capacity or strength compared with their peers. Quality of life in Australian boys with haemophilia is comparable to their European counterparts.

Lack of somatic alterations of MC1R in primary melanoma.

Germline variation of the melanocortin 1 receptor gene (MC1R) is a risk factor for cutaneous melanoma. Recent studies have indicated that the risk is significantly higher for melanomas with somatic BRAF mutations, suggesting that MC1R variants may have a more specific role than their demonstrated effects on skin and hair pigmentation. To address the possibility that MC1R may act like a tumor suppressor gene by creating a permissive condition for melanocytes with specific somatic mutations to proliferate or survive, we analyzed 103 primary melanomas for somatic MC1R mutations and copy number alterations. This cohort included melanomas from skin with and without chronic sun-induced damage, mucosal membranes, and acral skin (palms, soles, and subungual). We did not find somatic mutations or frequent DNA copy number alterations at the MC1R locus, nor any skewed pattern of copy number alterations that would favor one allele type over the other. In conclusion, our findings indicate that MC1R is not a frequent target of somatic alterations in melanoma.

Bidirectional promoter interference between two widely used internal heterologous promoters in a late-generation lentiviral construct.

Gene transfer vectors encoding two or more genes are potentially powerful research tools and are poised to play an increasingly important role in gene therapy applications. Common strategies employed to express more than one transgene per vector include the use of multiple promoters, internal ribosome entry site (IRES) elements, splicing signals and fusion proteins. Of these, the IRES elements and multiple promoters have been most widely used. The use of multiple promoters, however, may be compromised by interference between promoters, promoter silencing and vector rearrangements or deletions. In this study, we demonstrate promoter interference between two internal heterologous promoters in the context of a late-generation lentiviral vector. The interference, involving the human cytomegalovirus-immediate-early promoter and human elongation-factor-1alpha promoter, occurred bidirectionally with both promoters markedly impairing expression of the adjacent transcription unit. The data presented not only highlight the potential for interference between these widely-used promoters, but also the value of a sequential approach to vector construction that allows such effects to be recognized.

Serious infections from Bacillus sp.

Serious infections caused by organisms of the genus Bacillus developed in seven patients. Five drug abusers had either endocarditis or osteomyelitis, one leukemic patient had necrotizing fasciitis, and one patient had a ventriculoatrial shunt infection with recurrent bacteremia. All patients recovered. Experience with these cases reemphasizes the importance of not dismissing Bacillus organisms as culture contaminants, especially when isolated from blood, body fluids, or closed-space infections.

Tuberculoma of the brain.

Four patients with cerebral tuberculomas had presenting manifestations that included seizure disorder, exophthalmos, or extremity weakness. Although rare in this country, this diagnosis should not be overlooked in such patients, since combined surgical and medical therapy may be curative.

Staphylococcus aureus bacteremia: relationship between formation of antibodies to teichoic acid and development of metastatic abscesses.

Of 50 patients with bacteremia due to Staphylococcus aureus but without clinical evidence of endocarditis, 24 developed antibodies to the cell wall teichoic acid of S. aureus that were demonstrable by counterimmunoelectrophoresis. However, only 16 of the 24 patients developed titers of antibodies high enough for detection by passive gel diffusion. Eleven of the 16 patients developed evidence of complications due to metastatic infection. In contrast, of the 34 patients who were antibody-negative by gel diffusion, only one patient developed evidence of metastatic seeding. Thus, the development of antibodies to teichoic acid at a level detectable by the gel diffusion technique is regularly associated with complicated infections due to S. aureus that require more prolonged therapy, whereas bacteremic patients not developing such an antibody response rarely develop complications and may be treated with a two-week course of therapy.

Prophylactic antibiotics and wound infections following laminectomy for lumber disc herniation.

The authors review 531 consecutive operations for lumbar disc herniation performed on 496 patients by one neurosurgeon to determine the effect of prophylactic antibiotics upon postoperative wound infections. In this retrospective analysis 16 instances of sepsis were found, 11 considered to be major and five minor. In the 128 cases in which no antibacterial agents were given, 11 major and 1 minor infection occurred. Four minor infections developed in the 402 occasions when antibiotics were given in the perioperative period. Men had a significantly greater risk of developing infection than women. These data suggest that pre- and postoperative antibiotic therapy directed at a narrow spectrum of microorganisms reduced the incidence of significant wound infections in patients undergoing laminectomy for lumbar disc herniation.