Reflectance confocal microscopy evaluation of pigmented lesions on tattooed skin

Lasers in Medical Science - The evaluation of pigmented lesions on tattooed skin poses a diagnostic challenge for dermatologists, as a nevus may be partially or completely obscured by tattoo...     

Cellular resolution anatomical and molecular atlases for prenatal human brains

Increasing interest in studies of prenatal human brain development, particularly using new single-cell genomics and anatomical technologies to create cell atlases, creates a strong need for accurate and detailed anatomical reference atlases. In this study, we present two cellular-resolution digital anatomical atlases for prenatal human brain at postconceptional weeks (PCW) 15 and 21. Both atlases were annotated on sequential Nissl-stained sections covering brain-wide structures on the basis of combined analysis of cytoarchitecture, acetylcholinesterase staining, and an extensive marker gene expression dataset. This high information content dataset allowed reliable and accurate demarcation of developing cortical and subcortical structures and their subdivisions. Furthermore, using the anatomical atlases as a guide, spatial expression of 37 and 5 genes from the brains, respectively, at PCW 15 and 21 was annotated, illustrating reliable marker genes for many developing brain structures. Finally, the present study uncovered several novel developmental features, such as the lack of an outer subventricular zone in the hippocampal formation and entorhinal cortex, and the apparent extension of both cortical (excitatory) and subcortical (inhibitory) progenitors into the prenatal olfactory bulb. These comprehensive atlases provide useful tools for visualization, segmentation, targeting, imaging, and interpretation of brain structures of prenatal human brain, and for guiding and interpreting the next generation of cell census and connectome studies.     

Targeting human 8-oxoguanine glycosylase to mitochondria of oligodendrocytes protects against menadione-induced oxidative stress

Within the central nervous system (CNS), there is a differential susceptibility among cell types to certain pathological conditions believed to involve oxidative stress. Oligodendrocytes are extremely sensitive to oxidative stress, which correlates with a decreased ability to repair damage in mitochondrial DNA (mtDNA), as we have shown previously. To determine whether there is a causal relationship, studies were carried out to correct the deficit in repair of the oxidative damage in mtDNA in cultured oligodendrocytes. A vector containing a mitochondrial transport sequence (MTS) upstream of the sequence for human 8-oxoguanine-DNA glycosylase (OGG) was transfected into the cells. The efficiency of transfection and the localization of recombinant protein were determined by fluorescence microscopy and by Western blot analysis. Subsequent mtDNA repair studies, employing 100 micro M menadione to produce reactive oxygen species, showed a significant enhancement in repair of oxidative lesions in mtDNA of MTS-OGG transfected oligodendrocytes compared with cells transfected with vector only. Experiments were also conducted to determine the effect of changing mtDNA repair capacity on menadione-induced apoptosis in oligodendrocytes. These experiments show that targeting the OGG repair enzyme to mitochondria reduces the release of cytochrome c from the intermitochondrial space and the activation of caspase 9 in oligodendrocytes after exposure to menadione. Therefore, targeting of DNA repair enzymes to mitochondria appears to be a viable approach for the protection of cells against some of the deleterious effects of oxidative stress.     

Toxicity and carcinogenicity of furan in human diet

Furan is formed during commercial or domestic thermal treatment of food. The initial surveys of furan concentrations in heat-treated foods, published by European and US authorities, revealed the presence of relatively high furan levels in coffee, sauces, and soups. Importantly, furan is consistently found in commercial ready-to-eat baby foods. Furan induces hepatocellular tumors in rats and mice and bile duct tumors in rats with a high incidence. Epidemiological studies are not available. It is assumed that cis-2-butene-1,4-dial, the reactive metabolite of furan, is the causative agent leading to toxicity and carcinogenicity. Based on this data, furan is classified as a possible human carcinogen. The initial exposure estimates revealed a relatively small margin (~2,000) between human exposure and those furan doses, which induce liver tumors in experimental animals. As this may give rise for concern, in this review, the currently available toxicological and mechanistic data of furan are summarized and discussed with regard to its applicability in assessing the risk of furan in human diet.     

Gesundheitliche Risiken von Synephrin in Nahrungsergänzungsmitteln

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Synephrin ist ein sympathomimetisches Phenylethylaminderivat aus Zitrusfrüchten. Der Pflanzeninhaltsstoff wird in Form von...     

Androgen deprivation therapy for the treatment of prostate cancer: a focus on pharmacokinetics

Introduction: Medical therapy has undergone many changes as our understanding of prostate cancer cell biology has improved. Androgen deprivation therapy (ADT) remains the mainstay of therapy for metastatic disease. Metastatic castrate-resistant prostate cancer (CRPC) is an important concern since we are unable to stop progression with currently available agents.

Areas covered: Pharmacologic ADT is the most commonly used treatment for metastatic prostate cancer. Multiple agents are available for both first-line and second-line use: antiandrogens, estrogens, luteinizing hormone-releasing hormone agonists/antagonists, and CYP17 inhibitors. With adoption of these drugs, it is important to consider their pharmacokinetic and pharmacodynamic properties. Many undergo metabolism through cytochrome P450. Levels may be altered with co-administration of drugs acting as enzyme inhibitors or inducers. Understanding mechanism of action, metabolism, and excretion of these drugs allows clinicians to provide the best therapeutic care while minimizing adverse events.

Expert opinion: Many men with metastatic prostate cancer will progress to castration resistance. An understanding of resistance mechanisms at the cellular level has revealed new drug targets with hopes of halting or reversing progression of metastatic disease. Second-line agents, traditionally reserved for CRPC, are being studied in metastatic castrate-sensitive prostate cancer, and may offer practice-changing evidence supporting their use.