BACKGROUND Hydrocephalus is the abnormal accumulation of cerebrospinal fluid within the ventricles and subarachnoid spaces, resulting in increased intracranial pressure. The treatment of choice is placement of ventriculoperitoneal shunt. Ventriculoperitoneal shunt blockage is not an uncommon complication. Objective of the study was to find out the frequency, causes and site of ventriculoperiton...

Although root pressure and guttation presumably result from a high concentration of salt in the root xylem, the guttation fluid is very dilute. Measurements of the osmotic potential of the guttation liquid and of exudates at various levels in guttating plants indicate that salt is removed from the xylem in the upper part of plants, particularly in the leaves. The concentration of salt solutions...

Ralstonia causes wilt diseases by colonizing xylem vessels and disrupting water transport. The dogma is that bacterial biomass clogs reduces the flow of sap due to abundance. However, physiological mechanism disruption during untested. Using a tomato pseudosolanacearum GMI1000 model, we visualized quantified spatiotemporal dynamics wilt. First, measured stomatal conductance leaflets on mock-ino...

Specific biological characteristics of Xylella fastidiosa (Xf) Temecula were investigated in microfluidic flow chambers in vitro by examining the effect of xylem sap from Pierce’s disease (PD) susceptible V. vinifera and resistant V. smalliana grapevines on Xf cell growth, aggregation, biofilm formation, and motility. Growth of Xf was observed in both V. smalliana and V. vinifera xylem saps in ...

The ability to accurately evaluate hydrokinetic turbine concepts at small-scale in experimental facilities is important for the development of new devices. Problems introduced by working at lab-scale include operation in a transitional Reynolds number regime and cross-sectional blockage. These factors are shown to influence performance characteristics of a helical cross-flow turbine tested over...

Caffeic acid 3-O-methyltransferase (CAOMT) and caffeoyl-coenzyme A 3-O-methyltransferase (CCoAOMT) are involved in different methylation pathways in lignin biosynthesis. We previously showed that only the CCoAOMT was markedly induced during lignification in in vitro differentiating tracheary elements (TEs) of Zinnia elegans. To further examine the expression patterns of CAOMT in lignification, ...

Fluxes of mineral nutrients in the xylem are strongly influenced by interactions with the surrounding stem tissues and are probably regulated by them. Toward a mechanistic understanding of these interactions, we applied stable isotope tracers of magnesium, potassium, and calcium continuously to the transpiration stream of cut bean (Phaseolus vulgaris) shoots to study their radial exchange at th...

Xylem vessels in grapevines Vitis labrusca L. and Vitis riparia Michx. growing in New England contained air over winter and yet filled with xylem sap and recovered their maximum hydraulic conductance during the month before leaf expansion in late May. During this period root pressures between 10 and 100 kilopascals were measured. Although some air in vessels apparently dissolved in ascending xy...

The amygdalin content of four species of stone fruit trees (apricot, peach, plum, and bitter apricot trees) during different stages was investigated by thin-layer chromatography. The results showed that the amygdalin content in the kernel was much higher than in pulps, roots, shoots, or leaves, and the highest amygdalin occurred in bitter apricot kernels. The patterns of amygdalin content in le...

In tropical moist forests, seasonal drought limits plant survival, productivity and diversity. Drought-tolerance mechanisms of tropical species should reflect the maximum seasonal water deficits experienced in a particular habitat. We investigated stem xylem vulnerability to cavitation in nine tropical species with different life histories and habitat associations. Stem xylem vulnerability was ...