The effect of storage conditions on the permeability of porcine buccal mucosa
The impact of storage conditions on the permeability of porcine buccal mucosa to [3H]water and [14C]mannitol was assessed. The fresh porcine buccal tissue (fresh tissue) was obtained by utilizing pig heads within 24 hours of slaughter. The stored and frozen porcine buccal tissues (stored tissue and frozen tissue) were obtained after the storage of the tissue intact in the pig heads at 4 degrees C or -20 degrees C, respectively, for 24 h. The results demonstrated that the barrier properties of the porcine buccal mucosa were maintained with regard to [3H]water permeability when stored at 4 degrees C for 24 h. However, freezing the tissue resulted in tissue damage illustrated by a significant increase in [3H]water permeability. [14C]Mannitol does not appear to be a suitable model solute to assess the ex vivo permeability of porcine buccal mucosa due to its extremely low permeability.

title: Buccal permeation of [D-Ala(2), D-Leu(5)]enkephalin from liquid crystalline phases of glyceryl monooleate.
abstract: The ex vivo buccal permeability of a [D-Ala(2), D-Leu(5)]enkephalin (DADLE) and glyceryl monooleate (GMO) was examined from the cubic and lamellar liquid crystalline phases of GMO and aqueous phosphate-buffered saline (pH 7.4, PBS) solution across excised porcine buccal mucosa mounted in a Franz cell. GMO was released in vitro from the liquid crystalline phases indicating the erosion of the liquid crystal matrices. GMO released from the liquid crystalline matrices permeated the porcine buccal mucosa with fluxes of 0.10+/-0.03 and 0.07+/-0.00%/cm(2) per h for the cubic and lamellar phases, respectively. The flux of DADLE (1.21+/-0.32 and 1. 15+/-0.11%/cm(2) per h for the cubic and lamellar phases, respectively) from the liquid crystalline phases was significantly enhanced by the GMO compared with PBS solution (0.43+/-0.08%/cm(2) per h) during the initial permeation phase (t<3 h). Our results suggest that the cubic and lamellar liquid crystalline phases can be considered as promising buccal drug carriers for peptide drugs as well as acting as permeation enhancers.

title: FgVelB globally regulates sexual reproduction, mycotoxin production and pathogenicity in the cereal pathogen Fusarium graminearum.
abstract: The velvet genes are conserved in ascomycetous fungi and function as global regulators of differentiation and secondary metabolism. Here, we characterized one of the velvet genes, designated FgVelB, in the plant-pathogenic fungus Fusarium graminearum, which causes fusarium head blight in cereals and produces mycotoxins within plants. FgVelB-deleted (ΔFgVelB) strains produced fewer aerial mycelia with less pigmentation than those of the wild-type (WT) during vegetative growth. Under sexual development conditions, the ΔFgVelB strains produced no fruiting bodies but retained male fertility, and conidiation was threefold higher compared with the WT strain. Production of trichothecene and zearalenone was dramatically reduced compared with the WT strain. In addition, the ΔFgVelB strains were incapable of colonizing host plant tissues. Transcript analyses revealed that FgVelB was highly expressed during the sexual development stage, and may be regulated by a mitogen-activated protein kinase cascade. Microarray analysis showed that FgVelB affects regulatory pathways mediated by the mating-type loci and a G-protein alpha subunit, as well as primary and secondary metabolism. These results suggest that FgVelB has diverse biological functions, probably by acting as a member of a possible velvet protein complex, although identification of the FgVelB-FgVeA complex and the determination of its roles require further investigation.

title: On the contribution of deoxy-hemoglobin to MRI gray–white matter phase contrast at high field
abstract: High field (> or =7 T) MRI studies based on signal phase have been used to improve visualization of the fine structure of the brain, most notably the major white matter fiber bundles, the gray-white matter subdivision, and the laminar cortical architecture. The observed contrast has been attributed in part to local variations in magnetic susceptibility arising from iron in storage proteins and tissue lipid. Another contribution could come from the paramagnetic blood constituent deoxy-hemoglobin, the tissue concentration of which may vary through local variations in vascular density. To investigate this possibility, we examined phase contrast between gray and white matter in rats after intravenous administration of a superparamagnetic contrast agent at various dosages. At the maximum dosage (3 mg Fe/kg), which resulted in an estimated paramagnetic susceptibility shift 4-8 times larger than deoxy-hemoglobin, we observed a negligible increase in phase contrast between gray and white matter. This result suggests that endogenous deoxy-hemoglobin has no significant contribution to phase contrast between gray and white matter.

title: Guns and states: pediatric firearm injury.
abstract: A recent report indicates that firearm-related injuries are responsible for 30% of pediatric trauma fatality. The literature is however limited in examining pediatric firearm injuries and variations in state gun control laws. Therefore, we sought to examine the association between pediatric firearm injuries and the Stand-Your-Ground (SYG) and Child Access Protection (CAP) laws.



All pediatric (age, 0-20 years) hospitalizations with firearm injuries were identified from the Kids' Inpatient Database from 2006 and 2009. States were compared for SYG and CAP laws.



A total of 19,233 firearm injury hospitalizations were identified, with 64.7% assault, 27.2% accidental, and 3.1% suicide injury. Demographics for assault injury were as follows: mean age of 17.6 years, 88.4% male, 44.4% black, 18.2% Hispanic, 70.5% from metropolitan areas, and 50.1% from the poorest median income neighborhoods. Suicide injury cases were more likely to be white (57.8% vs. 16.6%, p < 0.001) and female (15.1% vs. 9.8%, p < 0.001). States with the SYG law were associated with increased accidental injury (odds ratio [OR], 1.282; p < 0.001). There was no statistical association between CAP law and the incidence of accidental injury or suicide. Multivariate logistic regression analysis found other predictive demographic factors for firearm injury: black (OR, 6.164), urban areas (OR, 1.557), poorest median income neighborhoods (OR, 2.785), male (OR, 28.602), and 16 years or older (OR, 37.308). Total economic burden was estimated at more than $1 billion dollars, with a median length of stay of 3 days, 8.4% discharge to rehabilitation, and 6.2% in-hospital mortality.



Pediatric firearm injuries continue to be a significant source of morbidity, mortality, and economic burden. A significant increase in accidental firearm injuries in states with the SYG law may highlight inadvertent effects of the law. Race, sex, and median income are additional contributing factors. Advocacy and focused educational efforts for specific socioeconomic and racial groups may potentially reduce firearm injuries.



Prognostic study, level II.

title: A rapid screening method for the detection of viable spores in powder using bioluminescence.
abstract: A rapid diagnosis of a biological threat in a powder sample is important for fi rst responders who have to make decisions on-site. The present culture-based method does not provide timely results, which is a critical barrier for a quick response when a suspicious powder sample is found. The ATP bioluminescence method, combined with a heat shock, was investigated to determine the presence of spores in powder. The results show that only spore-containing powder samples provided a dramatic increase in the bioluminescence signal after the heat shock, which induces germination of the spores. Various conditions were tested to fi nd the most effective and rapid germination procedure. Elevated temperatures (37 degrees C and 50 degrees C) were more effective in germination than room temperature. At 50 degrees C, a double-strength germinant was more effective in germination than the regular strength. The 37 degrees C/15 min procedure induced the germination of spores most effectively, while a 50 degrees C/2 min procedure provided reasonably high signals, so it could make the entire procedure even faster (< 5 min). The detection limit of the bioluminescence method is < 100 spores.

title: Sensitivity of MRI resonance frequency to the orientation of brain tissue microstructure
abstract: Recent advances in high-field (≥7 T) MRI have made it possible to study the fine structure of the human brain at the level of fiber bundles and cortical layers. In particular, techniques aimed at detecting MRI resonance frequency shifts originating from local variation in magnetic susceptibility and other sources have greatly improved the visualization of these structures. A recent theoretical study [He X, Yablonskiy DA (2009) Proc Natl Acad Sci USA 106:13558–13563] suggests that MRI resonance frequency may report not only on tissue composition, but also on microscopic compartmentalization of susceptibility inclusions and their orientation relative to the magnetic field. The proposed sensitivity to tissue structure may greatly expand the information available with conventional MRI techniques. To investigate this possibility, we studied postmortem tissue samples from human corpus callosum with an experimental design that allowed separation of microstructural effects from confounding macrostructural effects. The results show that MRI resonance frequency does depend on microstructural orientation. Furthermore, the spatial distribution of the resonance frequency shift suggests an origin related to anisotropic susceptibility effects rather than microscopic compartmentalization. This anisotropy, which has been shown to depend on molecular ordering, may provide valuable information about tissue molecular structure.