181.
Ureteral injury from blunt abdominal trauma: case report
Whitesides, E; Kozlowski, D L
The journal of trauma
36, Številka:
5
Journal Article
Injuries to the ureter from blunt trauma occur most often at the ureteropelvic junction. A delayed diagnosis is typical because of the presence of other injuries. Injuries occurring to other parts of ...
the ureter are usually over the transverse processes. The case of a 15-year-old boy with a mid-ureteral contusion from blunt trauma is presented, in whom compression or impaction of the ureter across the L5 vertebra caused edema late and therefore a partial obstruction. Such injuries should be considered when there is delayed abdominal or flank pain, especially in children.
več
Naroči gradivo
182.
Naroči gradivo
183.
Naroči gradivo
184.
An unexplained sequestration of latrunculin A is required in neutrophils for inhibition of actin polymerization
Pring, Martin; Cassimeris, Lynne; Zigmond, Sally H.
Cell motility and the cytoskeleton,
June 2002, Letnik:
52, Številka:
2
Journal Article
Latrunculin A (LatA) is a toxic natural product that causes disruption of the actin cytoskeleton in many eukaryotic cells at submicromolar concentrations. LatA has been found to bind G‐actin with a ...
dissociation constant of 0.2 μM, and more recently to bind profilin‐G‐actin and, weakly, thymosin β4‐G‐actin. A number of investigators have used LatA as a G‐actin sequestering agent. Thus, we studied neutrophil chemotaxis and its requisite conversion of G‐actin to F‐actin, supported by an extensive pool of G‐actin, mainly bound to thymosin β4. Calculations suggest that the affinity of LatA is insufficient to cause significant sequestration of this pool, and the pool's buffering action should protect neutrophils from depletion of productive G‐actin species by submicromolar LatA. Nonetheless, we found that both chemoattractant stimulated migration and F‐actin polymerization in neutrophils were inhibited by LatA at these concentrations. The latter effect was accompanied by sequestration of LatA and showed a cell density dependence that was consistent with G‐actin sequestration. The apparent contradiction between the calculations and the experimental observations could be reconciled by assuming the presence of an accessory species, of unknown normal function, which forms a high affinity ternary complex with LatA and G‐actin, thus causing the cells to concentrate LatA. Other models that could not be ruled out also invoke new actions of LatA, suggesting caution in the interpretation of its effects on cells. Cell Motil. Cytoskeleton 52:122–130, 2002. © 2002 Wiley‐Liss, Inc.
več
185.
Naroči gradivo
186.
Naroči gradivo
187.
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