Agminated fibroblastic connective tissue nevus in a 1‐year‐old boy

Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy.     

ENDOSCOPIC NASOBILIARY DRAINAGE: CURRENT INDICATIONS AND EVALUATION OF THE PRODUCTS

Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.     

Brain N-acetylaspartate is elevated in Pelizaeus-Merzbacher disease with PLP1 duplication.

OBJECTIVE: To assess alterations in brain metabolites of patients with Pelizaeus-Merzbacher disease (PMD) with the proteolipid protein gene 1 (PLP1) duplications using quantitative proton MRS. METHODS: Five unrelated male Japanese patients with PMD with PLP1 duplications were analyzed using automated proton brain examination with the point resolved spectroscopy technique (repetition and echo time of 5,000 and 30 msec). Localized spectra in the posterior portion of the centrum semiovale were acquired, and absolute metabolite concentrations were calculated using the LCModel. RESULTS: Absolute concentrations of N-acetylaspartate (NAA), creatine (Cr), and myoinositol (MI) were increased by 16% (p < 0.01), 43% (p < 0.001), and 31% (p < 0.01) in patients with PMD as compared with age-matched controls. There was no statistical difference in choline concentration. CONCLUSION: The increased concentration of NAA, which could not be detected by previous relative quantitation methods, suggests two possibilities: axonal involvement secondary to dysmyelination, or increased cell population of oligodendrocyte progenitors. Elevated Cr and MI concentrations may reflect the reactive astrocytic gliosis. Our study thus emphasizes the importance of absolute quantitation of metabolites to investigate the disease mechanism of the dysmyelinating disorders of the CNS.     

Defective calcium transport in platelets from stroke-prone spontaneously hypertensive rats

Aggregation and secretion of washed platelets from stroke-prone spontaneously hypertensive rats(SHRSP) were greatly reduced by the development of hypertension in comparison with age-matched normotensive WKY platelets. In an attempt to clarify the mechanism of the defective functions, Ca2+ transport in platelets from SHRSP and WKY were studied. Changes of cytoplasmic free Ca2+ concentration ([Ca2+]i) were examined by using Quin 2. [Ca2+]i increase in response to thrombin(0.028 - 0.11 U/ml) was significantly delayed in SHRSP platelets compared with that of age-matched WKY platelets. The time(sec) to peak in [Ca2+]i was about two times longer in SHRSP platelets than in WKY platelets. [Ca2+]i levels at resting state were significantly lower in SHRSP platelets while there was no difference in maximal [Ca2+]i level in response to thrombin (0.031 - 0.125 U/ml) between the two strains. In addition thrombin-induced 45Ca2+ uptake was significantly delayed in SHRSP platelets. This delay of [Ca2+]i increase following thrombin stimulation might be associated with the hypofunctions of SHRSP platelets.     

Big mitogen-activated protein kinase 1 (BMK1)/extracellular signal regulated kinase 5 (ERK5) is involved in platelet-derived growth factor (PDGF)-induced vascular smooth muscle cell migration

Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.