Hair analysis and self-report of methamphetamine use by methamphetamine dependent individuals

The questions of whether the dose of drug that is consumed corresponds to drug concentration levels in hair and how results of hair analyses can be interpreted are still debated. The aim of this study was to investigate (1) whether there is a correlation between doses of Methamphetamine (MA) use and MA concentration levels in hair and (2) whether results of hair analyses can be used to estimate dose, frequency, and patterns of MA use. In this study, segmental hair analysis was performed through consecutive 1cm as well as 1-4 cm (=3 cm) segmental hair lengths. MA dependent individuals (n=9) provided information on doses (0.25-4 g/day) of MA use as well as the frequency of MA use. The concentrations of MA and its metabolite amphetamine (AP) in hair were determined using gas chromatography/mass spectrometry (GC/MS). One-way analysis of variance (ANOVA) test was performed to evaluate whether MA and AP concentrations in consecutive 1cm length segmental hair were consistent with the history of MA use. The cumulative doses of MA use calculated from the daily dose and the frequency during 1-4 months were well correlated to the concentrations of MA and AP in 1-4 cm segmental hair length (correlation coefficient, r=0.87 for MA and r=0.77 for AP). The results from this study show the patterns and histories of MA use from MA dependent individuals and could assist in the interpretation of hair results in forensic toxicology as well as in rehabilitation and treatment programs.     

Two major medicinal honeys have different mechanisms of bactericidal activity

Honey is increasingly valued for its antibacterial activity, but knowledge regarding the mechanism of action is still incomplete. We assessed the bactericidal activity and mechanism of action of Revamil® source (RS) honey and manuka honey, the sources of two major medical-grade honeys. RS honey killed Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa within 2 hours, whereas manuka honey had such rapid activity only against B. subtilis. After 24 hours of incubation, both honeys killed all tested bacteria, including methicillin-resistant Staphylococcus aureus, but manuka honey retained activity up to higher dilutions than RS honey. Bee defensin-1 and H₂O₂ were the major factors involved in rapid bactericidal activity of RS honey. These factors were absent in manuka honey, but this honey contained 44-fold higher concentrations of methylglyoxal than RS honey. Methylglyoxal was a major bactericidal factor in manuka honey, but after neutralization of this compound manuka honey retained bactericidal activity due to several unknown factors. RS and manuka honey have highly distinct compositions of bactericidal factors, resulting in large differences in bactericidal activity.     

Exercise during pregnancy mitigates Alzheimer-like pathology in mouse offspring

Physical activity protects brain function in healthy individuals and those with Alzheimer's disease (AD). Evidence for beneficial effects of parental exercise on the health status of their progeny is sparse and limited to nondiseased individuals. Here, we questioned whether maternal running interferes with offspring's AD-like pathology and sought to decipher the underlying mechanisms in TgCRND8 mice. Maternal stimulation was provided by voluntary wheel running vs. standard housing during pregnancy. Following 5 mo of standard housing of transgenic and wild-type offspring, their brains were examined for AD-related pathology and/or plasticity changes. Running during pregnancy reduced β-amyloid (Aβ) plaque burden (-35%, P=0.017) and amyloidogenic APP processing in transgenic offspring and further improved the neurovascular function by orchestrating different Aβ transporters and increasing angiogenesis (+29%, P=0.022). This effect was accompanied by diminished inflammation, as indicated by reduced microgliosis (-20%, P=0.002) and down-regulation of other proinflammatory mediators, and resulted in less oxidative stress, as nitrotyrosine levels declined (-28%, P=0.029). Moreover, plasticity changes (in terms of up-regulation of reelin, synaptophysin, and ARC) were found not only in transgenic but also in wild-type offspring. We conclude that exercise during pregnancy provides long-lasting protection from neurodegeneration and improves brain plasticity in the otherwise unstimulated progeny.     

The Larval Eye of Nannochoristid Scorpionflies (Insecta,Mecoptera)

Abstract The stemmata of last–instar Nannochoristalarvae are compound eyes composed of 10 or more ommatidia. Each ommatidium has four Semper cells, four distal and four proximal retinula cells which form a cruciform and layered rhabdom. The ommatidia are separated by epidermal cells (possibly rudimentary pigment cells). Corneal lenses are lacking. At the posterior edge, aberrant stemma units may be present which lack a dioptric apparatus and have a star–shaped rhabdom composed of at least six retinula cells. The stemmata of Nannochoristaappear to be derived from stemmata of the Panorpa-type (Mecoptera-Panorpidae). Differences between the stemmata of Nannochoristaand Panorpacan be explained as adaptations to aquatic life (flat cornea) or as regression. A compound larval eye is ascribed to the ground plan of the Mecoptera sensu latoand is considered a genuine plesiomorphy. The identical basic number (seven) of stemmata in the Neuropteroid/Coleoptera assemblage, Amphiesmenoptera and some Mecoptera (Bittacidae, Boreidae) is attributed to parallel evolution.     

Inhibitory effects of digoxin and ouabain on aldosterone synthesis in human adrenocortical NCI-H295 cells

The present study was to investigate the effects and action mechanisms of digoxin and ouabain on steroidogenesis in human adrenocortical NCI-H295 cells. Administration of digoxin or ouabain for 24 h decreased the basal and angiotensin II (Ang II)-stimulated release of aldosterone by NCI-H295 cells. The conversions of corticosterone (substrate of cytochrome P450 aldosterone synthase, P450c11AS) to aldosterone or deoxycortisol (substrate of cytochrome P450 11beta-hydroxylase, P450c11beta) to cortisol were reduced by digoxin or ouabain. The basal and 22-hydroxy-cholesterol (a membrane-permeable cholesterol, substrate of cytochrome P450 side-chain cleavage enzyme, P450scc)-stimulated pregnenolone release in mitochondria was inhibited by digoxin or ouabain. Digoxin or ouabain suppressed the basal and Ang II-stimulated protein expression of steroidogenic acute regulatory (StAR) protein and P450scc. Incubation of digoxin or ouabain for 24 h reduced P450c11AS mRNA expression in NCI-H295 cells. Digoxin or ouabain (10(-6) M, 24 h)-treated cells showed a lower resting intracellular Ca2+ concentration ([Ca2+]i) and an attenuated response of [Ca2+]i to Ang II. Since no significant cytotoxicity was observed at 10(-6) M digoxin or ouabain, the digoxin- or ouabain-induced decrease of aldosterone or cortisol release was not associated with cytotoxicity. These results demonstrate that digoxin or ouabain inhibits the aldosterone or cortisol release via reduction of P450c11AS or P450c11beta and P450scc activities, inhibition of StAR and P450scc protein expression, suppression of P450c11AS mRNA expression, and attenuation of Ca2+ mobilization in NCI-H295 cells.     

Functional measurement of local proteolytic activity in living cells of invasive and non-invasive tumors

Proteolytic cleavage of extracellular matrix (ECM) and disruption of tissue architecture are fundamental features of tumor cell invasion. The proteolytic activity is focused in close proximity to the tumor cells. Here, we describe the possibility to quantify local proteolytic activity in the microenvironment of larger cell populations by the electrical resistance breakdown assay. The assay utilizes the transepithelial electrical resistance (TEER) of an epithelial monolayer as a sensitive indicator of monolayer integrity and permeability. Local destruction of ECM by single tumor cells was demonstrated by a second assay, based on a fluorescent matrix coating on cover slides. Local digestion of the matrix results in a reduction of fluorescence. Primary cells derived from high and low grade brain tumors as well as established cell lines of malignant gliomas and non-neural tumors of different origin (melanoma, cervical carcinoma, and breast carcinoma) were compared. Differences in proteolytic activity between tumor entities were demonstrated in both assays. Primary cells of high grade gliomas and cell lines showed TEER breakdown and local matrix destruction, while low grade brain tumors lacked matrix disintegration and disruption of cell monolayers. Taken together, both assays are capable of demonstrating local proteolytic activity and thus are versatile tools for distinguishing high and low invasive tumor cells with a potential application as diagnostic and prognostic markers in clinical investigations. The advantage of the matrix digestion assay is the requirement of only very low tumor cell numbers, whereas measurement of TEER enables precise quantification of local proteolytic processes in large and even heterogeneous tumor cultures.     

Ontogenetic shifts in intraguild predation on thrips by phytoseiid mites: the relevance of body size and diet specialization

In greenhouse agroecosystems, a guild of spider mite predators may consist of the oligophagous predatory mite Phytoseiulus persimilis Athias-Henriot, the polyphagous predatory mite Neoseiulus californicus McGregor (both Acari: Phytoseiidae) and the primarily herbivorous but facultatively predatory western flower thrips Frankliniella occidentalis Pergande (Thysanoptera: Thripidae). Diet-specialization and the predator body size relative to prey are crucial factors in predation on F. occidentalis by P. persimilis and N. californicus. Here, it was tested whether the relevance of these factors changes during predator ontogeny. First, the predator (protonymphs and adult females of P. persimilis and N. californicus): prey (F. occidentalis first instars) body size ratios were measured. Second, the aggressiveness of P. persimilis and N. californicus towards F. occidentalis was assessed. Third, survival, development and oviposition of P. persimilis and N. californicus with F. occidentalis prey was determined. The body size ranking was P. persimilis females > N. californicus females > P. persimilis protonymphs > N. californicus protonymphs. Neoseiulus californicus females were the most aggressive predators, followed by highly aggressive N. californicus protonymphs and moderately aggressive P. persimilis protonymphs. Phytoseiulus persimilis females did not attack thrips. Frankliniella occidentalis larvae are an alternative prey for juvenile N. californicus and P. persimilis, enabling them to reach adulthood. Females of N. californicus but not P. persimilis sustained egg production with thrips prey. Within the guild studied here, N. californicus females are the most harmful predators for F. occidentalis larvae, followed by N. californicus and P. persimilis juveniles. Phytoseiulus persimilis females are harmless to F. occidentalis.     

The modulatory role of transforming growth factor beta1 and androstenedione on follicle-stimulating hormone-induced gelatinase secretion and steroidogenesis in rat granulosa cells

To investigate the potential roles of matrix metalloproteinases (MMPs) in ovarian granulosa cell differentiation, we studied the interactive effects of FSH and local ovarian factors, transforming growth factor beta1 (TGFbeta1) and androstenedione, on gelatinase secretion and progesterone production in rat ovarian granulosa cells. Granulosa cells of eCG-primed immature rats were treated once with various doses of FSH and TGFbeta1 and androstenedione alone or in combinations for 2 days. Conditioned media were analyzed for gelatinase activity using gelatin-zymography/densitometry and progesterone levels using enzyme immunoassay. Cell lysates were analyzed for steroidogenic acute regulatory (StAR) and cholesterol side-chain-cleavage (P450scc) enzyme protein levels. This study demonstrates for the first time that FSH dose-dependently increased the secretion of a major 63-kDa gelatinase and minor 92- and 67-kDa gelatinases. TGFbeta1 also dose-dependently increased the secretion of 63-kDa gelatinase, while androstenedione alone had no effect. The 92-kDa gelatinase was identified as the pro-MMP9 that could be cleaved by aminophenylmercuric acetate into the 83-kDa active form. Importantly, we show that TGFbeta1 and androgen act in an additive manner to enhance FSH stimulatory effects both on the secretion of gelatinases and the production of progesterone. We further show by immunoblotting that the enhancing effect of TGFbeta1 and androstenedione on FSH-stimulated steroidogenesis is partly mediated through the increased level of StAR protein and/or P450scc enzyme. In conclusion, this study indicates that, during antral follicle development, TGFbeta1 and androgen act to enhance FSH promotion of granulosa cell differentiation and that the process may involve the interplay of modulating cell- to-matrix/cell-to-cell interaction and steroidogenic activity.