Pseudomelanosis of the bladder: a case report

BACKGROUND: Pseudomelanosis is due to deposition of pseudomelanin and is best known as the entity pseudomelanosis coli. However, pseudomelanosis in the urinary tract has never been described. Pigmentation of the urothelium, known as melanosis vesica, is characterized by deposition of melanin pigment granules without signs of atypia. Simple (true) melanosis of the bladder is uncommon. CASE: A 52-year-old man presented with macroscopic hematuria. Cystoscopy and microscopic evaluation revealed pigmentation of the bladder urothelium diagnosed as pseudomelanosis vesica due to deposits of melaninlike pigment in the absence of detectable melanocytes and detectable by urine cytology. CONCLUSION: Pseudomelanosis vesica is a benign lesion that has never before been observed in the urinary tract.     

Bacillus agar-exedens,a new species,decomposing agar

Conclusions In stable manure, leafmold and soils (especially those with a high content of organic material) agar decomposing bacilli are relatively common. Different types of these organisms were isolated, the type described asBacillus agar-exedens being the one most frequently met. The occurrence of these bacteria in materials with a high content of organic matter suggests the presence in these materials of higher organic compounds, especially apt for their nutrition.     

The huminfaction of high-moor peat

Summary Changes in ion-exchange capacity and N-content of the organic matter occur when high-moor peat is composted at room temperature. The ion-exchange capacity increases, though slowly.Nitrogen is incorporated into the organic matter when the peat is composted with mineral fertilizers and N is applied as urea. The fixed nitrogen is not exchangeable with BaCl₂ or Al₂(SO₄)₃. It is assumed that micro-organisms play a part in this fixation.Nitrogen losses occur when, because of the nitrification process, the pH values drop below 5.5.     

Brain-type creatine kinase has a crucial role in osteoclast-mediated bone resorption

Osteoclasts differentiate from precursor cells of the monocyte-macrophage lineage and subsequently become activated to be competent for bone resorption through programs primarily governed by receptor activator of nuclear factor-kappaB ligand in cooperation with macrophage colony-stimulating factor. Proteins prominently expressed at late phases of osteoclastogenesis and with a supportive role in osteoclast function are potential therapeutic targets for bone-remodeling disorders. In this study, we used a proteomics approach to show that abundance of the brain-type cytoplasmic creatine kinase (Ckb) is greatly increased during osteoclastogenesis. Decreasing Ckb abundance by RNA interference or blocking its enzymatic activity with a pharmacological inhibitor, cyclocreatine, suppressed the bone-resorbing activity of osteoclasts grown in vitro via combined effects on actin ring formation, RhoA GTPase activity and vacuolar ATPase function. Activities of osteoclasts derived from Ckb-/- mice were similarly affected. In vivo studies showed that Ckb-/- mice were better protected against bone loss induced by ovariectomy, lipopolysaccharide challenge or interleukin-1 treatment than wild-type controls. Furthermore, administration of cyclocreatine or adenoviruses harboring Ckb small hairpin RNA attenuated bone loss in rat and mouse models. Our findings establish an important role for Ckb in the bone-resorbing function of osteoclasts and underscore its potential as a new molecular target for antiresorptive drug development.     

A Tail-Anchored Myotonic Dystrophy Protein Kinase Isoform Induces Perinuclear Clustering of Mitochondria,Autophagy, and Apoptosis

Background

Studies on the myotonic dystrophy protein kinase (DMPK) gene and gene products have thus far mainly concentrated on the fate of length mutation in the (CTG)n repeat at the DNA level and consequences of repeat expansion at the RNA level in DM1 patients and disease models. Surprisingly little is known about the function of DMPK protein products.

Methodology/Principal Findings

We demonstrate here that transient expression of one major protein product of the human gene, the hDMPK A isoform with a long tail anchor, results in mitochondrial fragmentation and clustering in the perinuclear region. Clustering occurred in a variety of cell types and was enhanced by an intact tubulin cytoskeleton. In addition to morphomechanical changes, hDMPK A expression induces physiological changes like loss of mitochondrial membrane potential, increased autophagy activity, and leakage of cytochrome c from the mitochondrial intermembrane space accompanied by apoptosis. Truncation analysis using YFP-hDMPK A fusion constructs revealed that the protein''s tail domain was necessary and sufficient to evoke mitochondrial clustering behavior.

Conclusion/Significance

Our data suggest that the expression level of the DMPK A isoform needs to be tightly controlled in cells where the hDMPK gene is expressed. We speculate that aberrant splice isoform expression might be a codetermining factor in manifestation of specific DM1 features in patients.