•Pax6SeyNeu/+ mice serve as a platform for elucidating PAX6-dependent neuroanatomy.•MRI & histology show deviations in regional volume & white matter tract thickness.•PAX6-deficient mammals show ...ageing-related structural neural plasticity reduction.•Some neuroanatomical differences are conserved, while some are human-specific.
PAX6 encodes a highly conserved transcription factor necessary for normal development of the eyes and central nervous system. Heterozygous loss-of-function mutations in PAX6 cause the disorder aniridia in humans and the Small eye trait in mice. Aniridia is a congenital and progressive disorder known for ocular phenotypes; however, recently, consequences of PAX6 haploinsufficiency in the brains of aniridia patients have been identified. These findings span structural and functional abnormalities, including deficits in cognitive and sensory processing. Furthermore, some of these abnormalities are accelerated as aniridia patients age. Although some functional abnormalities may be explained by structural changes, variability of results remain, and the effects of PAX6 heterozygous loss-of-function mutations on neuroanatomy, particularly with regard to aging, have yet to be resolved. Our study used high-resolution magnetic resonance imaging (MRI) and histology to investigate structural consequences of such mutations in the adult brain of our aniridia mouse model, Small eye Neuherberg allele (Pax6SeyNeu/+), at two adult age groups. Using both MRI and histology enables a direct comparison with human studies, while providing higher resolution for detection of more subtle changes. We show volumetric changes in major brain regions of the the Pax6SeyNeu/+ mouse compared to wild-type including genotype- and age-related olfactory bulb differences, age-related cerebellum differences, and genotype-related eye differences. We also show alterations in thickness of major interhemispheric commissures, particularly those anteriorly located within the brain including the optic chiasm, corpus callosum, and anterior commissure. Together, these genotype and age related changes to brain volumes and structures suggest a global decrease in adult brain structural plasticity in our Pax6SeyNeu/+ mice.
The differential diagnosis of CNS white matter disease is broad, and can be divided into vascular, metabolic, infective, or inflammatory aetiologies. Isolated inflammatory disorders of the CNS are ...often associated with demyelination, and the two terms (inflammatory and demyelinating) are often used in conjunction. When the disease is monophasic, the term acute disseminated encephalomyelitis (ADEM) is used.1 ADEM typically occurs as a post-infectious phenomenon, and by definition, must be an isolated (monophasic) episode. If a relapse occurs shortly after the ADEM presentation in association with a further infection or steroid withdrawal, the term MDEM (multiphasic disseminated encephalomyelitis) is used. When there are relapses or progressive disease, the term multiple sclerosis (MS) is used (for full recommended diagnostic criteria for multiple sclerosis refer to McDonald and colleagues2).
The authors investigated the relationship between degree of lateralization and noise phobia in 48 domestic dogs (
Canis familiaris
) by scoring paw preference to hold a food object and relating it to ...reactivity to the sounds of thunderstorms and fireworks, measured by playback and a questionnaire. The dogs without a significant paw preference were significantly more reactive to the sounds than the dogs with either a left-paw or right-paw preference. Intense reactivity, therefore, is associated with a weaker strength of cerebral lateralization. The authors note the similarity between their finding and the weaker hand preferences shown in humans suffering extreme levels of anxiety and suggest neural mechanisms that may be involved.
Adults aged 65 and over comprise approximately 15% of the U.S. population, yet research regarding their experiences during later life transitions remains relatively scant. Our aim in conducting this ...qualitative study was to better understand relational, developmental, and family life cycle factors that older adults identify as impacting their perceptions of aging and wellness in the context of transitioning into assisted living facilities. In-depth interviews with six participants revealed that attachment across the life span and historic parent–child relationships substantially impacted participants’ perceptions and experiences during later life transitions. These findings support the importance of systemic counseling interventions targeted toward strengthening parent–child relationships across the life span. We conclude with implications for systemic counselors.
•The relationship between preferential paw use and problem solving was investigated for the first time in domestic dogs.•Non-lateralized (ambilateral) dogs were more successful i.e. faster at ...accessing the apparatus than lateralized dogs.•No difference in problem-solving performance was found between right and left-pawed dogs.
In a number of species, individuals showing lateralized hand/paw usage (i.e. the preferential use of either the right or left paw) compared to ambilateral individuals have been shown to be more proactive in novel situations. In the current study we used an established test to assess preferential paw usage in dogs (the Kong test) and then compared the performance of ambilateral and lateralized dogs as well as left- vs. right-pawed dogs in a novel manipulative problem solving task. Results showed an equal proportion of ambilateral and lateralized dogs but contrary to predictions non-lateralized dogs were faster at accessing the apparatus in test trials. No differences emerged between right- and left-pawed dogs. Results are discussed in relation to previous studies on lateralization.
The senior author altered his surgical technique during total hip arthroplasty from capsulectomy and capsulotomy with closure of the external rotator muscles to capsulotomy and capsulorrhaphy. One ...thousand patients (500 treated with each procedure) were studied retrospectively in order to determine the prevalences of dislocation after surgery with the two different techniques. The prevalence of dislocation was 2.8% after the capsulectomy and capsulotomy, whereas it was 0.6% after the new technique; this was a significant decrease in the rate of dislocation (p < 0.005, symbol: see text = 0.10).
Minimal-incision total hip arthroplasty Goldstein, Wayne M; Branson, Jill J; Berland, Kimberly A ...
Journal of bone and joint surgery. American volume,
01/2003, Letnik:
85-A Suppl 4
Journal Article
The ion photon emission microscope (IPEM) is a technique developed at Sandia National Laboratories (SNL) to study radiation effects in integrated circuits with high energy, heavy ions, such as those ...produced by the 88” cyclotron at Lawrence Berkeley National Laboratory (LBNL). In this method, an ion-luminescent film is used to produce photons from the point of ion impact. The photons emitted due to an ion impact are imaged on a position-sensitive detector to determine the location of a single event effect (SEE). Due to stringent resolution, intensity, wavelength, decay time, and radiation tolerance demands, an engineered material with very specific properties is required to act as the luminescent film. The requirements for this material are extensive. It must produce a high enough induced luminescent intensity so at least one photon is detected per ion hit. The emission wavelength must match the sensitivity of the detector used, and the luminescent decay time must be short enough to limit accidental coincidences. In addition, the material must be easy to handle and its luminescent properties must be tolerant to radiation damage. Materials studied for this application include plastic scintillators, GaN and GaN/InGaN quantum well structures, and lanthanide-activated ceramic phosphors. Results from characterization studies on these materials will be presented; including photoluminescence, cathodoluminescence, ion beam induced luminescence, luminescent decay times, and radiation damage. Results indicate that the ceramic phosphors are currently proving to be the ideal material for IPEM investigations.
As surgeons learn to perform minimally invasive hip arthroplasty procedures, the various techniques will evolve and one or two approaches may eventually become the standard. Currently, most of these ...procedures are reserved for the nonmorbidly obese patients; however, as techniques are perfected and surgeons gain experience, this patient population may eventually be served. Surgeons must present information to patients in a responsible manner and clarify the actual versus perceived advantages of the MITH. It is unfortunate that some patients may abandon an experienced surgeon (who will likely give an excellent long-term clinical outcome) for an inexperienced surgeon who can provide a smaller incision (with long-term benefits thus far unknown). Surgeons must also address the same comorbidities and complications for MITH arthroplasty as with the conventional approaches such as DVT, fat embolism, pain control, and wound healing. Routines for postoperative care and screening for complications must remain within the plan of care for the standard incision and MITH patient.information to patients in a responsible manner and clarify the actual versus perceived advantages of the MITH. It is unfortunate that some patients may abandon an experienced surgeon (who will likely give an excellent long-term clinical outcome) for an inexperienced surgeon who can provide a smaller incision (with long-term benefits thus far unknown). Surgeons must also address the same comorbidities and complications for MITH arthroplasty as with the conventional approaches such as DVT, fat embolism, pain control, and wound healing. Routines for postoperative care and screening for complications must remain within the plan of care for the standard incision and MITH patient.
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