Association between SNPs in defined functional pathways and risk of early or late toxicity as well as individual radiosensitivity

Background and purpose

The aim of this study was to determine the impact of functional single nucleotide polymorphism (SNP) pathways involved in the ROS pathway, DNA repair, or TGFB1 signaling on acute or late normal toxicity as well as individual radiosensitivity.

Materials and methods

Patients receiving breast-conserving surgery and radiotherapy were examined either for erythema (n?=?83), fibrosis (n?=?123), or individual radiosensitivity (n?=?123). The 17 SNPs analyzed are involved in the ROS pathway (GSTP1, SOD2, NQO1, NOS3, XDH), DNA repair (XRCC1, XRCC3, XRCC6, ERCC2, LIG4, ATM) or TGFB signaling (SKIL, EP300, APC, AXIN1, TGFB1). Associations with biological and clinical endpoints were studied for single SNPs but especially for combinations of SNPs assuming that a SNP is either beneficial or deleterious and needs to be weighted.

Results

With one exception, no significant association was seen between a single SNP and the three endpoints studied. No significant associations were also observed when applying a multi-SNP model assuming that each SNP was deleterious. In contrast, significant associations were obtained when SNPs were suggested to be either beneficial or deleterious. These associations increased, when each SNP was weighted individually. Detailed analysis revealed that both erythema and individual radiosensitivity especially depend on SNPs affecting DNA repair and TGFB1 signaling, while SNPs in ROS pathway were of minor importance.

Conclusion

Functional pathways of SNPs may be used to form a risk score allowing to predict acute and late radiation-induced toxicity but also to unravel the underlying biological mechanisms.

     

Endurance running acutely raises plasma osteoprotegerin and lowers plasma receptor activator of nuclear factor kappa B ligand

Abstract The balance of the 2 cytokines, osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa B ligand (soluble (s)RANKL), is known to have considerable influence on bone formation and degradation. Plasma concentrations of OPG and (s)RANKL were determined in a total of 31 long-distance runners before and immediately after running distances of either 15 or 42.195 km, respectively. In both groups of endurance runners, a significant decrease of sRANKL was observed during the run, the extent of which correlated to the running distance. Furthermore, OPG increased only in runners covering the marathon distance of 42.195 km. We hypothesize that the known positive effect of long-distance running on the skeletal mass may be mediated by the OPG/sRANKL system.     

Improving endograft stability by accommodation onto the aortic bifurcation.

PURPOSE: To report the technique for deploying a 3-part endovascular graft onto the native aortic bifurcation for greater stent-graft stability. TECHNIQUE: The Zenith Composite Endovascular Graft is a 3-part system consisting of a proximal tubular body with an uncovered Gianturco Z stent, a distal bifurcated body, and a contralateral leg. Proximally, 8-mm flexible interstent gaps facilitate precise infrarenal aortic placement, even in angulated necks. Technically, the bifurcated part is deployed first and pulled down to the aortic bifurcation, while the tubular main body and contralateral leg deployment follow. Using this technique to accommodate the graft onto the natural aortic bifurcation, distal stability can be enhanced and graft migration minimized. CONCLUSION: The Composite configuration can be an alternative to ensure a higher security index in difficult anatomies. It may be beneficial in patients with short (10-15 mm), angulated (>60 degrees ), or conical necks and deserves investigation in these patient populations.     

Prevalence and determinants of exocrine pancreatic insufficiency among older adults: results of a population-based study

OBJECTIVE: The prevalence and main determinants of exocrine pancreatic insufficiency were investigated in a large population-based sample of older adults by measuring pancreatic elastase-1 in stool. MATERIAL AND METHODS: The study comprised 914 participants aged 50 to 75 years recruited by their general practitioner during a general health examination. All participants and their physicians were asked to fill out a standardized questionnaire which contained information on socio-demographic and lifestyle factors as well as medical history. Native stool was examined for pancreatic elastase-1 with a commercially available ELISA (ScheBo Tech, Giessen, Germany). RESULTS: Overall, 524 women and 390 men aged 50 to 75 years (mean age 61.9 years) were included in the analysis. In total, 105 (11.5%) of the 914 subjects showed signs of exocrine pancreatic insufficiency (EPI) with =200 microg elastase-1/g stool, and 47 (5.1%) subjects showed signs of a severe exocrine pancreatic insufficiency (SEPI, < 100 microg elastase-1/g stool). There was a clear increase in EPI with age. Patients taking angiotensin-converting enzyme (ACE) inhibitors had a lower prevalence than subjects without this medication; these associations persisted after adjustment for covariates. CONCLUSIONS: Prevalence of EPI increases with age and seems to be tentatively higher in men than in women. However, smoking seems to be an independent risk factor for EPI and SEPI whereas ACE-inhibitor intake might be a protective factor. The latter finding may even point to new options in the treatment of chronic pancreatitis.     

Early Childhood Gut Microbiomes Show Strong Geographic Differences Among Subjects at High Risk for Type 1 Diabetes

OBJECTIVE

Gut microbiome dysbiosis is associated with numerous diseases, including type 1 diabetes. This pilot study determines how geographical location affects the microbiome of infants at high risk for type 1 diabetes in a population of homogenous HLA class II genotypes.

RESEARCH DESIGN AND METHODS

High-throughput 16S rRNA sequencing was performed on stool samples collected from 90 high-risk, nonautoimmune infants participating in The Environmental Determinants of Diabetes in the Young (TEDDY) study in the U.S., Germany, Sweden, and Finland.

RESULTS

Study site–specific patterns of gut colonization share characteristics across continents. Finland and Colorado have a significantly lower bacterial diversity, while Sweden and Washington state are dominated by Bifidobacterium in early life. Bacterial community diversity over time is significantly different by geographical location.

CONCLUSIONS

The microbiome of high-risk infants is associated with geographical location. Future studies aiming to identify the microbiome disease phenotype need to carefully consider the geographical origin of subjects.     

Typ-1-Diabetes: Früherkennung und Ansätze zur Prävention

Die Diabetologie - Die Inzidenz des Typ-1-Diabetes nimmt zu, besonders bei Kleinkindern. Die Erkrankung kann effektiv bereits im asymptomatischen Frühstadium der Inselautoimmunität...     

Age-related islet autoantibody incidence in offspring of patients with type 1 diabetes

Aims/hypothesis  

Seroconversion to islet autoantibodies precedes type 1 diabetes. This study aimed to identify periods of high seroconversion incidence, which could be targeted for mechanistic and therapeutic studies.     

Extra-large letter spacing improves reading in dyslexia

Although the causes of dyslexia are still debated, all researchers agree that the main challenge is to find ways that allow a child with dyslexia to read more words in less time, because reading more is undisputedly the most efficient intervention for dyslexia. Sophisticated training programs exist, but they typically target the component skills of reading, such as phonological awareness. After the component skills have improved, the main challenge remains (that is, reading deficits must be treated by reading more--a vicious circle for a dyslexic child). Here, we show that a simple manipulation of letter spacing substantially improved text reading performance on the fly (without any training) in a large, unselected sample of Italian and French dyslexic children. Extra-large letter spacing helps reading, because dyslexics are abnormally affected by crowding, a perceptual phenomenon with detrimental effects on letter recognition that is modulated by the spacing between letters. Extra-large letter spacing may help to break the vicious circle by rendering the reading material more easily accessible.