Early-response biological dosimetry--recommended countermeasure enhancements for mass-casualty radiological incidents and terrorism

The effective medical management of a suspected acute radiation overexposure incident necessitates recording dynamic medical data, measuring appropriate radiation bioassays, and estimating dose from dosimeters and radioactivity assessments in order to provide diagnostic information to the treating physician and a dose assessment for personnel radiation protection records. The accepted generic multiparameter and early-response approach includes measuring radioactivity and monitoring the exposed individual; observing and recording prodromal signs/symptoms and erythema; obtaining complete blood counts with white blood cell differential; sampling blood for the chromosome-aberration cytogenetic bioassay using the "gold standard" dicentric assay (translocation assay for long times after exposure) for dose assessment; bioassay sampling, if appropriate, to determine radioactivity contamination; and using other available dosimetry approaches. In the event of a radiological mass-casualty incident, current national resources need to be enhanced to provide suitable dose assessment and medical triage and diagnoses. This capability should be broadly based and include stockpiling reagents and devices; establishing deployable (i.e., hematology and biodosimetry) laboratories and reference (i.e., cytogenetic biodosimetry, radiation bioassay) laboratories; networking qualified reference radioactivity-counting bioassay laboratories, cytogenetic biodosimetry, and deployable hematology laboratories with the medical responder community and national radiation protection program; and researching efforts to identify novel radiation biomarkers and develop applied biological dosimetry assays monitored with clinical, deployable, and hand-held analytical systems. These research and applied science efforts should ultimately contribute towards approved, regulated biodosimetry devices or diagnostic tests integrated into a national radioprotection program.     

Inhibition of return in saccadic eye movements

Inhibition of return (IOR) is a phenomenon in which responses generated to targets at previously attended locations are delayed. It has been suggested that IOR affords a mechanism for optimizing the inspection of novel locations and that it is generated by oculomotor reflexes mediated by the superior colliculus. In this investigation, we measured the effects of IOR on the metrics of saccadic eye movements made to novel and previously attended locations. Saccades made to cued target locations, as well as to other targets within the same hemifield, had longer latencies than saccades made towards the novel, uncued hemifield. We further found that the amplitudes of saccades towards the cued hemifield were more hypometric, but only when the amplitude could not be pre-programmed. These results provide evidence that IOR influences spatial, as well as temporal, parameters of saccadic eye movements and suggest that the exogenous orienting of attention, in addition to influencing target detection, also influences oculomotor programming.     

Modelling neuroinflammatory phenotypes <Emphasis Type="Italic">in vivo</Emphasis>

Inflammation of the central nervous system is an important but poorly understood part of neurological disease. After acute brain injury or infection there is a complex inflammatory response that involves activation of microglia and astrocytes and increased production of cytokines, chemokines, acute phase proteins, and complement factors. Antibodies and T lymphocytes may be involved in the response as well. In neurodegenerative disease, where injury is more subtle but consistent, the inflammatory response is continuous. The purpose of this prolonged response is unclear, but it is likely that some of its components are beneficial and others are harmful. Animal models of neurological disease can be used to dissect the specific role of individual mediators of the inflammatory response and assess their potential benefit. To illustrate this approach, we discuss how mutant mice expressing different levels of the cytokine transforming growth factor β-1 (TGF-β1), a major modulator of inflammation, produce important neuroinflammatory phenotypes. We then demonstrate how crosses of TGF-β1 mutant mice with mouse models of Alzheimer's disease (AD) produced important new information on the role of inflammation in AD and on the expression of different neuropathological phenotypes that characterize this disease.     

The Ty1-copia families SALIRE and Cotzilla populating the Beta vulgaris genome show remarkable differences in abundance, chromosomal distribution, and age

Long terminal repeat (LTR) retrotransposons are major components of plant genomes influencing genome size and evolution. Using two separate approaches, we identified the Ty1-copia retrotransposon families Cotzilla and SALIRE in the Beta vulgaris (sugar beet) genome. While SALIRE elements are similar to typical Ty1-copia retrotransposons, Cotzilla elements belong to a lineage called Sireviruses. Hallmarks of Cotzilla retrotransposons are the existence of an additional putative env-like open reading frame upstream of the 3′LTR, an extended gag region, and a frameshift separating the gag and pol genes. Detected in a c ₀ t-1 DNA library, Cotzilla elements belong to the most abundant retrotransposon families in B. vulgaris and are relatively homogenous and evolutionarily young. In contrast, the SALIRE family has relatively few copies, is diverged, and most likely ancient. As revealed by fluorescent in situ hybridization, SALIRE elements target predominantly gene-rich euchromatic regions, while Cotzilla retrotransposons are abundant in the intercalary and pericentromeric heterochromatin. The analysis of two retrotransposons from the same subclass contrasting in abundance, age, sequence diversity, and localization gives insight in the heterogeneity of LTR retrotransposons populating a plant genome.     

Bone anchored hearing aid in single sided deafness: outcome in right-handed patients

Objective

To assess the benefits in terms of sound localization, to evaluate speech discrimination in noise, to appraise the prosthesis benefit and to identify outcome in right and left handed patients when BAHA are implanted on the right or on the left deaf side.

Methods

Two years prospective study in a tertiary referral center. Tests consist on Hearing in Noise Test (HINT) and sound localization after 6 months of BAHA use. Quality of life was assessed by the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire. The paired T-test and the analysis of variance were used for the statistical measures.

Results

Twenty-one subjects participated in this study. HINT: patients score better when speech and noise are spatially separated and noise is not presented to the healthy ear. In the right-handed group (left dominant brain), unaided left-implanted patients performed better than right-implanted patient when speech is in front and noise to the good ear; when speech is presented to the good ear and noise to the front, aided right-implanted patients performed better than aided left-implanted patients. Sound localization: correct answers attain 35% at best. No statistical difference between the frequencies was found, neither between the left and right implanted patients. APHAB: the score improvement is statistically significant for the global score, the background noise subscale at 5 weeks and for the reverberation subscale at 6 months.

Conclusion

It seems that left dominant hemisphere is able to filter crossed noise better than the right hemisphere. Results of uncrossed speech to the dominant left brain are better than the uncrossed speech to the non-dominant right brain.     

Quality of interaction between at‐risk infants and caregiver at 12–15 months is associated with 3‐year autism outcome

Background: Recent models of the early emergence of autism spectrum disorder (ASD) propose that infant intrinsic risk susceptibilities in behaviour may be amplified by interaction within the early social environment into an increasingly atypical developmental trajectory. This study examines whether 6‐ and 12‐month parent–infant interactions in at‐risk siblings differ from those with low‐risk and whether – in at‐risk siblings – such interactions predict later 3‐year classification of ASD or no ASD. Method: Within the British Autism Study of Infant Siblings (BASIS), 6‐min videotaped episodes of parent–infant free play in infants at 6–10 months (45 at‐risk siblings and 47 low‐risk siblings) and 12–15 months (43 at‐risk siblings and 48 low‐risk siblings) in a laboratory setting were rated on the Manchester Assessment of Caregiver‐Infant Interaction (MACI), blind to participant information. Standard tests were administered for concurrent behavioural signs of ASD features and developmental level. Systematic consensus diagnostic classification of ASD was made at 3 years for the at‐risk siblings. Results: Parent nondirectiveness and sensitive responsiveness differed in relation to ASD/risk status (at‐risk ASD, at‐risk no‐ASD and low‐risk) at both 6 and 12 months. At 6 months, infant liveliness was lower in the at‐risk groups; at 12 months, infant attentiveness to parent and positive affect were lower in the at‐risk group later diagnosed with ASD. Dyadic mutuality and intensity of engagement showed a group effect at 12 months. Dyadic mutuality, infant positive affect and infant attentiveness to parent at 12 months (but not 6 months) predicted 3‐year ASD outcome, whereas infant ASD‐related behavioural atypicality did not. Conclusions: This is the first prospective evidence that early dyadic interaction between at‐risk infants and their parents is associated with later diagnostic outcome in ASD. Possible explanations for these findings and their theoretical implications are considered.