A comparative study on potential cytogenetic fingerprints for radiation LET in human lymphocytes

PURPOSE: To carry out a comparative study on potential cytogenetic fingerprints for radiation LET in human metaphase lymphocytes. MATERIALS AND METHOD: Human lymphocytes were irradiated in vitro with 3.0 Gy 60Co gamma-rays, 0.9 Gy 3H beta-rays or 0.2 Gy 2.7 Mev neutrons. Detailed chromosome aberrations were analysed by combined FISH with pan-telomere staining and specific whole-chromosome painting (1, 2 and 4). Total chromosome translocations and insertions were also analysed by multicolour whole-chromosome painting (chromosomes 1, 2 and 4 orange, chromosomes 3, 5 and 6 green). RESULTS: Among the six proposed radiation cytogenetic fingerprints, the ratio of total simple translocations to insertions (I-ratio), showed the largest difference between low-LET 60Co gamma-ray and high-LET neutron radiation. The ratios of complete exchanges to incomplete rejoinings [S(I)-ratio] and dicentrics to interstitial deletions (H-ratio), showed a similar significant difference between low- and high-LET radiation. The ratios of centric rings to interstitial deletion (G-ratio) showed a trend of LET-related difference, but the difference was not significant in this data set. The ratios of dicentrics to centric rings (F-ratio) and apparent complete exchanges to hidden complete exchanges [S(II)-ratio], showed no difference between low- and high-LET radiation. In the 1426 radiation-induced chromosome aberrations observed after 52 h culture, evidence for sister-chromatid fusion but not telomere addition was found. CONCLUSION: Pan-telomere staining plus specific whole chromosome painting allows simultaneous and objective detection of complete or incomplete chromosome exchanges and interstitial or terminal deletions in human peripheral lymphocytes. Of the six proposed cytogenetic ratios, the I-ratio is the most effective cytogenetic fingerprint for distinguishing low-LET from high-LET radiation in human metaphase human lymphocytes.     

A new look at reaction time in schizophrenia

Schizophrenia patients demonstrate impaired manual reaction time (RT), but not saccadic RT, when given traditional tasks. To determine whether the manual RT time impairment could be eliminated by providing imperative stimuli to the finger (thus providing stimulus-response compatibility), we tested 28 chronic schizophrenic patients on finger-lift RT to visual (VIS), tactile plus visual (TAC+VIS), and auditory plus tactile plus visual (AUD+TAC+VIS) stimuli. The patients (a) were significantly slower than controls (n=28) in all three tasks, (b) showed bimodality, with 43% of patients having means and variances nearly identical to control values, and (c) had RTs significantly closer to control values in the TAC+VIS and AUD+TAC+VIS tasks than in the VIS task. The inability to normalize finger-lift RT in schizophrenia represents a genuine slowing of this response system regardless of stimulus-response compatibility. We consider other possible explanations for the differences between manual and saccadic RT, including the notion that excess processing capacity for saccadic RT may be masking possible deficits in that system.     

Longitudinal 1H MRS of rat forebrain from infancy to adulthood reveals adolescence as a distinctive phase of neurometabolite development

This study represents the first longitudinal, within‐subject ¹H MRS investigation of the developing rat brain spanning infancy, adolescence and early adulthood. We obtained neurometabolite profiles from a voxel located in a central location of the forebrain, centered on the striatum, with smaller contributions for the cortex, thalamus and hypothalamus, on postnatal days 7, 35 and 60. Water‐scaled metabolite signals were corrected for T₁ effects and quantified using the automated processing software LCModel, yielding molal concentrations. Our findings indicate age‐related concentration changes in N‐acetylaspartate + N‐acetylaspartylglutamate, myo‐inositol, glutamate + glutamine, taurine, creatine + phosphocreatine and glycerophosphocholine + phosphocholine. Using a repeated measures design and analysis, we identified significant neurodevelopment changes across all three developmental ages and identified adolescence as a distinctive phase in normative neurometabolic brain development. Between postnatal days 35 and 60, changes were observed in the concentrations of N‐acetylaspartate + N‐acetylaspartylglutamate, glutamate + glutamine and glycerophosphocholine + phosphocholine. Our data replicate past studies of early neurometabolite development and, for the first time, link maturational profiles in the same subjects across infancy, adolescence and adulthood. Copyright © 2013 John Wiley & Sons, Ltd.     

How benign is hematuria? Using genetics to predict prognosis

Hematuria is a common presenting feature of glomerular disease and is sometimes associated with kidney failure later in life. Where isolated microscopic hematuria occurs in children and young adults, an underlying monogenic disorder, such as Alport syndrome or thin basement membrane nephropathy, is frequently responsible. In this review, these and other diseases, which often present with isolated microscopic hematuria, including hereditary angiopathy, nephropathy, aneurysms, and muscle cramps (HANAC) syndrome, IgA nephropathy, and CFHR5 nephropathy, are discussed together with the associated molecular pathology, clinical features, and prognosis. Genetic testing for these conditions used in clinical practice can provide important diagnostic and prognostic information that is relevant to the patient and their family, particularly when kidney transplantation is considered.     

Visceral Pain And Life Quality In Persons With Spinal Cordinjury: A Brief Report

Abstract

Background/Objective: Few studies have examined the prevalence of visceral pain in persons with spinalcord injury (SCI), and virtually no studies have looked at the relationship between visceral pain and selfreportedquality of life. We examined the frequency of reported visceral pain at 5, 10, and 15 years afterinjury to determine whether the presence of visceral pain is related to quality of life, and to determine towhat extent visceral pain should be of concern to clinicians treating patients with SCI.

Methods: Visceral pain and quality of life in persons with SCI were compared from a combined CraigHospital and National Model SCI Systems database at 5 (N=33), 10 (N=132), and 15 (N=96) years afterinjury.

Results: The rates of visceral pain increased at each measurement (10% at year 5, 22% at year 10, and 32%at year 15); although these numbers reflect cross-sectional data, they do show a clear statistical change.Only a limited true longitudinal sample was available, but at 10 years after injury, individuals who hadreported visceral pain at any time reported a significantly lower quality of life than those never experiencingvisceral pain, F1,188 = 3.95, P <0.05.

Conclusions: Although visceral pain may not be as prevalent as the more researched neuropathic andmusculoskeletal subtypes of pain, it may account for a higher percentage of people with SCI who report painthan previously recognized. More quantitative and longitudinal research is needed to examine therelationship of visceral pain with overall quality of life and to pursue interventions.