BACKGROUND The objective of the study was to evaluate and compare how apical enlargement with K3 and K3XF nickel-titanium (NiTi) rotary instruments reduces the root thickness in the danger zone and affects canal transportation and centering ability in mandibular molar mesial canals in a manikin extracted tooth model. MATERIAL AND METHODS Seventy-two mesial root canals of first mandibular mola...

Trigeminal neuralgia caused by a tentorial dural arteriovenous fistula has rarely been reported. The mechanism underlying the development of trigeminal neuralgia has been reported to be the compression of the root entry zone by the arterialized draining vein. However, the cases showing refractory or recurrent neuralgia could imply the presence of another underlying mechanism. We herein describe...

Gravitropism refers to the growth or movement of plants that is influenced by gravity. Roots exhibit positive gravitropism, and the root cap is thought to be the gravity-sensing site. In some plants, the root cap requires light irradiation for positive gravitropic responses. However, the mechanisms regulating this phenomenon are unknown. We herein report that maize roots exposed to white light ...

Thapsigargin, a specific inhibitor of most animal intracellular SERCA-type Ca2+ pumps present in the sarcoplasmic/endoplasmic reticulum, was originally isolated from the roots of the Mediterranean plant Thapsia gargancia L. Here, we demonstrate that this root-derived compound is capable of altering root gravitropism in Arabidopsis thaliana. Thapsigargin concentrations as low as 0.1 microM alter...

It is not known to what degree aquaporin-facilitated water uptake differs between root developmental regions and types of root. The aim of this study was to measure aquaporin-dependent water flow in the main types of root and root developmental regions of 14- to 17-d-old barley plants and to identify candidate aquaporins which mediate this flow. Water flow at root level was related to flow at c...

October 2003 ORAL HEALTH 75 T he ‘Apical Control Zone’ is a matrix-like region created in the apical third of the root canal space. The zone demonstrates an exaggerated taper from the clinician defined apical constriction whether this is spatially a linear or point determination. This enhanced taper in the apical control zone provides resistance form against the condensation pressures of obtura...

Water deficit caused by addition of polyethylene glycol 6000 at -0.5 MPa water potential to well-aerated nutrient solution for 48 h inhibited the elongation of maize (Zea mays) seedling primary roots. Segmental growth rates in the root elongation zone were maintained 0 to 3 mm behind the tip, but in comparison with well-watered control roots, progressive growth inhibition was initiated by water...

†Background Aluminium (Al) toxicity is the most important soil constraint for plant growth and development in acid soils. The mechanism of Al-induced inhibition of root elongation is still not well understood, and it is a matter of debate whether the primary lesions of Al toxicity are apoplastic or symplastic. † Scope The present review focuses on the role of the apoplast in Al toxicity and res...