Carotenoids and Antioxidant Nutrients following Burn Injury a

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72213/1/j.1749-6632.1993.tb26193.x.pd

Tet2 Rescues Age-Related Regenerative Decline and Enhances Cognitive Function in the Adult Mouse Brain.

Restoring adult stem cell function provides an exciting approach for rejuvenating the aging brain. However, molecular mechanisms mediating neurogenic rejuvenation remain elusive. Here we report that the enzyme ten eleven translocation methylcytosine dioxygenase 2 (Tet2), which catalyzes the production of 5-hydroxymethylcytosine (5hmC), rescues age-related decline in adult neurogenesis and enhances cognition in mice. We detected a decrease in Tet2 expression and 5hmC levels in the aged hippocampus associated with adult neurogenesis. Mimicking an aged condition in young adults by abrogating Tet2 expression within the hippocampal neurogenic niche, or adult neural stem cells, decreased neurogenesis and impaired learning and memory. In a heterochronic parabiosis rejuvenation model, hippocampal Tet2 expression was restored. Overexpressing Tet2 in the hippocampal neurogenic niche of mature adults increased 5hmC associated with neurogenic processes, offset the precipitous age-related decline in neurogenesis, and enhanced learning and memory. Our data identify Tet2 as a key molecular mediator of neurogenic rejuvenation

Gingival fluid cytokine expression and subgingival bacterial counts during pregnancy and postpartum: a case series

Objectives: The aim of this study was to assess gingival fluid (GCF) cytokine messenger RNA (mRNA) levels, subgingival bacteria, and clinical periodontal conditions during a normal pregnancy to postpartum. Materials and methods: Subgingival bacterial samples were analyzed with the checkerboard DNA-DNA hybridization method. GCF samples were assessed with real-time PCR including five proinflammatory cytokines and secretory leukocyte protease inhibitor. Results: Nineteen pregnant women with a mean age of 32years (S.D. ± 4years, range 26-42) participated in the study. Full-mouth bleeding scores (BOP) decreased from an average of 41.2% (S.D. ± 18.6%) at the 12th week of pregnancy to 26.6% (S.D. ± 14.4%) at the 4-6weeks postpartum (p < 0.001). Between week 12 and 4-6weeks postpartum, the mean probing pocket depth changed from 2.4mm (S.D. ± 0.4) to 2.3mm (S.D. ± 0.3) (p = 0.34). Higher counts of Eubacterium saburreum, Parvimonas micra, Selenomonas noxia, and Staphylococcus aureus were found at week 12 of pregnancy than at the 4-6weeks postpartum examinations (p < 0.001). During and after pregnancy, statistically significant correlations between BOP scores and bacterial counts were observed. BOP scores and GCF levels of selected cytokines were not related to each other and no differences in GCF levels of the cytokines were observed between samples from the 12th week of pregnancy to 4-6weeks postpartum. Decreasing postpartum counts of Porphyromonas endodontalis and Pseudomonas aeruginosa were associated with decreasing levels of Il-8 and Il-1β. Conclusions: BOP decreased after pregnancy without any active periodontal therapy. Associations between bacterial counts and cytokine levels varied greatly in pregnant women with gingivitis and a normal pregnancy outcome. Postpartum associations between GCF cytokines and bacterial counts were more consistent. Clinical relevance: Combined assessments of gingival fluid cytokines and subgingival bacteria may provide important information on host respons

Positive Cross Correlations in a Normal-Conducting Fermionic Beam Splitter

We investigate a beam splitter experiment implemented in a normal conducting fermionic electron gas in the quantum Hall regime. The cross-correlations between the current fluctuations in the two exit leads of the three terminal device are found to be negative, zero or even positive depending on the scattering mechanism within the device. Reversal of the cross-correlations sign occurs due to interaction between different edge-states and does not reflect the statistics of the fermionic particles which `antibunch'.Comment: 4 pages, 4 figure

Neuronal O-GlcNAcylation Improves Cognitive Function in the Aged Mouse Brain.

Mounting evidence in animal models indicates potential for rejuvenation of cellular and cognitive functions in the aging brain. However, the ability to utilize this potential is predicated on identifying molecular targets that reverse the effects of aging in vulnerable regions of the brain, such as the hippocampus. The dynamic post-translational modification O-linked N-Acetylglucosamine (O-GlcNAc) has emerged as an attractive target for regulating aging-specific synaptic alterations as well as neurodegeneration. While speculation exists about the role of O-GlcNAc in neurodegenerative conditions, such as Alzheimer's disease, its role in physiological brain aging remains largely unexplored. Here, we report that countering age-related decreased O-GlcNAc transferase (OGT) expression and O-GlcNAcylation ameliorates cognitive impairments in aged mice. Mimicking an aged condition in young adults by abrogating OGT, using a temporally controlled neuron-specific conditional knockout mouse model, recapitulated cellular and cognitive features of brain aging. Conversely, overexpressing OGT in mature hippocampal neurons using a viral-mediated approach enhanced associative fear memory in young adult mice. Excitingly, in aged mice overexpressing neuronal OGT in the aged hippocampus rescued in part age-related impairments in spatial learning and memory as well as associative fear memory. Our data identify O-GlcNAcylaton as a key molecular mediator promoting cognitive rejuvenation

Preparedness for Life-Threatening Situations in a Pediatric Tertiary-Care University Children's Hospital: A Survey.

Pediatric nurses and physicians are rarely exposed to life-threatening events. Understanding the needs of clinicians is key for designing continuing training programs. A survey exploring preparedness to manage life-threatening events as well as training needs was mailed to all clinically active nurses and physicians at a tertiary-level referral children's hospital. Overall, 469 participants out of 871 answered the questionnaire (54% response rate). Respondents felt well or very well (nurses 93%, physicians 74%) prepared to recognize a deteriorating child and rated their theoretical understanding (70% well or very well prepared) of how to manage life-threatening situations significantly higher (p < 0.0001) than their cardiopulmonary resuscitation (CPR) preparedness (52% well or very well prepared). Both perceived theoretical understanding (p < 0.0001) and CPR preparedness (p < 0.002) were rated higher among nurses than physicians. Arrhythmias, shock, cardiac arrest and airway management constitute main areas of perceived training need. In conclusion, although a majority of pediatric nurses and physicians felt sufficiently trained to recognize a deteriorating child, their perceived ability to actively manage life-threatening events was inferior to their theoretical understanding of how to resuscitate a child. A high degree of institutional confidence and identification of areas of training need provide a good foundation for customizing future continuing education programs

Strong compensation of the quantum fluctuation corrections in clean superconductor

The theory of fluctuation conductivity for an arbitrary impurity concentration including ultra-clean limit is developed. It is demonstrated that the formal divergency of the fluctuation density of states contribution obtained previously for the clean case is removed by the correct treatment of the non-local ballistic electron scattering. We show that in the ultra-clean limit ($T\tau \gg \sqrt{\frac{T_c}{T-T_c}}$) the density-of-states quantum corrections are canceled by the Maki-Thompson term and only quasi-classical paraconductivity remains.Comment: 7 pages 2 figure

The chameleon groups of Richard J. Thompson: automorphisms and dynamics

The automorphism groups of several of Thompson's countable groups of piecewise linear homeomorphisms of the line and circle are computed and it is shown that the outer automorphism groups of these groups are relatively small. These results can be interpreted as stability results for certain structures of PL functions on the circle. Machinery is developed to relate the structures on the circle to corresponding structures on the line

Microsecond folding dynamics of the F13W G29A mutant of the B domain of staphylococcal protein A by laser-induced temperature jump

The small size (58 residues) and simple structure of the B domain of staphylococcal protein A (BdpA) have led to this domain being a paradigm for theoretical studies of folding. Experimental studies of the folding of BdpA have been limited by the rapidity of its folding kinetics. We report the folding kinetics of a fluorescent mutant of BdpA (G29A F13W), named F13W*, using nanosecond laser-induced temperature jump experiments. Automation of the apparatus has permitted large data sets to be acquired that provide excellent signal-to-noise ratio over a wide range of experimental conditions. By measuring the temperature and denaturant dependence of equilibrium and kinetic data for F13W*, we show that thermodynamic modeling of multidimensional equilibrium and kinetic surfaces is a robust method that allows reliable extrapolation of rate constants to regions of the folding landscape not directly accessible experimentally. The results reveal that F13W* is the fastest-folding protein of its size studied to date, with a maximum folding rate constant at 0 M guanidinium chloride and 45°C of 249,000 (s-1). Assuming the single-exponential kinetics represent barrier-limited folding, these data limit the value for the preexponential factor for folding of this protein to at least ≈2 x 10(6) s(-1)