Fibroblast-mediated delivery of GDNF induces neuronal-like outgrowth in PC12 cells

HYPOTHESIS: Recombinantly modified cells deliver neurotrophic factors with the capacity to induce differentiation and the outgrowth of neurites of rat pheochromocytoma cells 12 (PC12) serving as a neuronal model. BACKGROUND: The benefit of cochlea implant (CI) is depending, among other factors, on the number of surviving spiral ganglion neurons (SGN). Studies have shown that the external application of neurotrophic factors in combination with electrical stimulation increases the survival rate of SGN after ototrauma. Therefore, functionalization of electrodes with recombinantly modified cells providing neurotrophic factors to the SGN for inducing survival mechanisms may be an approach to realize drug delivery to the cochlea. METHODS: Murine NIH3T3 cells were recombinantly modified with an infectious lentiviral monocistronic and bicistronic system to synthesize glial cell line-derived neurotrophic factor and the green fluorescent protein. Free glial cell line-derived neurotrophic factor from the supernatant of the modified NIH3T3 cells was added to rat PC12, and the neuronal-like outgrowth was determined for 10 days. RESULTS: A significant neuronal-like outgrowth appeared as early as Day 3 after the application of the supernatant. CONCLUSION: The results indicate that the established in vitro model represents a powerful basic model for determining signal pathways between neuronal-like processing PC12 cells and cellular drug delivery systems.     

The influence of 5,10 methylenetetrahydrofolate reductase genotypes on enzyme activity in placental tissue

Objective To study the effects of heterozygosity and homozygosity for the C677T mutation of the 5,10 methylenetetrahydrofolate reductase (MTHFR) gene on the activity of this enzyme in placental tissue from pregnancies not affected by neural tube defect.
Design Placental tissue was genotyped for the C677T variants of MTHFR. Total enzyme activity and residual activity after heating to 46°C for 5 minutes was then measured.
Setting A teaching hospital.
Sample Placental samples (   n = 200  ), one from each of 200 uncomplicated term deliveries.
Main outcome measures Total and residual enzyme activity for MTHFR.
Results Placentae heterozygous for the C677T mutation of the MTHFR gene had significantly lower total enzyme activity than those without the mutation; the lowest activity occurred in homozygotes for the mutation. The same pattern was seen in relation to enzyme activity after heating.
Conclusion This study demonstrates that reduced enzyme activity is associated with the C677T variant of MTHFX in placental tissue. This is an important metabolic step in folic acid metabolism and pro-     

An event related functional magnetic resonance imaging study of facial emotion processing in Asperger syndrome.

BACKGROUND: People with Asperger syndrome (AS) have life-long deficits in social behavior. The biological basis of this is unknown, but most likely includes impaired processing of facial emotion. Human social communication involves processing different facial emotions, and at different intensities. However nobody has examined brain function in people with AS when implicitly (unconsciously) processing four primary emotions at varying emotional intensities. METHODS: We used event-related functional magnetic resonance imaging (MRI) to examine neural responses when people with AS and controls implicitly processed neutral expressions, and mild (25%) and intense (100%) expressions of fear, disgust, happiness, and sadness. We included 18 right-handed adults; 9 with AS and 9 healthy controls who did not differ significantly in IQ. RESULTS: Both groups significantly activated 'face perception' areas when viewing neutral faces, including fusiform and extrastriate cortices. Further, both groups had significantly increased activation of fusiform and other extrastriate regions to increasing intensities of fear and happiness. However, people with AS generally showed fusiform and extrastriate hyporesponsiveness compared to controls across emotion types and intensities. CONCLUSIONS: Fusiform and extrastriate cortices are activated by facial expressions of four primary emotions in people with AS, but generally to a lesser degree than controls. This may partly explain the social impairments of people with AS.     

Artefacts found in computed radiography.

Artefacts on radiographic images are distracting and may compromise accurate diagnosis. Although most artefacts that occur in conventional radiography have become familiar, computed radiography (CR) systems produce artefacts that differ from those found in conventional radiography. We have encountered a variety of artefacts in CR images that were produced from four different models plate reader. These artefacts have been identified and traced to the imaging plate, plate reader, image processing software or laser printer or to operator error. Understanding the potential sources of CR artefacts will aid in identifying and resolving problems quickly and help prevent future occurrences.     

Tumor Control and Toxicity after SBRT for Ultracentral,Central, and Paramediastinal Lung Tumors

Purpose

Increased rates of toxicity have been described after stereotactic body radiation therapy (SBRT) for central lung tumors within 2 cm of the proximal bronchial tree (PBT). Recent studies have defined a new class of ultracentral tumors. We report our experience treating ultracentral, central, and paramediastinal tumors with SBRT and compare toxicity, disease control, and survival rates.

Serological survey following SARS-COV-2 outbreaks at long-term care facilities in metro Vancouver,British Columbia: Implications for outbreak management and infection control policies

A cross-sectional serological survey was carried out in two long-term care facilities that experienced COVID-19 outbreaks in order to evaluate current clinical COVID-19 case definitions. Among individuals with a negative or no previous COVID-19 diagnostic test, myalgias, headache, and loss of appetite were associated with serological reactivity. The US CDC probable case definition was also associated with seropositivity. Public health and infection control practitioners should consider these findings for case exclusion in outbreak settings.