21 research outputs found
Variations In Volume And Dimensions Of Rays And Their Effect On Wood Properties Of Teak
Six teak (Tectona grandis L.) trees were sampled from two districts in Bangladesh. Ray proportion and dimensions of rays (ray area, ray height, and ray width) on tangential sections were measured, and the influence of ray volume on longitudinal and radial compression strength was investigated. Ray proportion remained more or less constant from pith to bark. Number of rays/mm2 and dimensions of rays became constant at about ring 10 from the pith. Ray proportion and dimensions showed characteristic values from tree to tree and were not affected by growth rate. The trees that had the highest ray volume showed higher specific gravity and higher radial compression strength. It can be considered as the influence of the rays. Hence it may be advisable to breed teak with a high ray proportion
Hypokalemic rhabdomyolysis due to WDHA syndrome caused by VIP-producing composite pheochromocytoma in a case of neurofibromatosis type 1
A 47-year-old woman with neurofibromatosis type 1 suffered from general muscle weakness and watery diarrhea. Laboratory findings showed elevated muscular enzymes, severe hypokalemia and excessive production of catecholamines and vasoactive intestinal polypeptide (VIP). A computed tomography scan showed a 10 cm left adrenal mass, in which [131I]-metaiodobenzylguanidine scintigraphy showed high uptake. After she underwent surgical removal of the tumor, all the symptoms and signs subsided. A histological study revealed that the mass consisted of pheochromocytoma and ganglioneuroma, respectively producing catecholamines and VIP. In immunohistochemical staining of neurofibromin, pheochromocytoma and ganglion cells showed positive staining, whereas the staining was negative for nerve bundles and Schwann cells. We concluded that the patient had hypokalemic rhabdomyolysis due to watery diarrhea, hypokalemia and achlorhydria (WDHA) syndrome, which was induced by a VIP-producing composite pheochromocytoma. Composite pheochromocytoma is a neuroendocrine tumor that is composed of pheochromocytoma and ganglioneuroma, both derived from the neural crest. Deficiency of neurofibromin in Schwann cells might have played an important role in the development and the growth of the composite pheochromocytoma in this patient