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H Kasprzak

Publications and source records attributed to H Kasprzak.

12 recordsLinked to original sources
PubMed1992

[Qualitative analysis of the elasticity of the bovine cornea by holographic interferometry].

Double-exposure holographic interferometry is used for deformation analysis of the surface of bovine corneas subjected to intraocular pressure increase. Reproducible individual fringe patterns are recorded for an intraocular pressure of 1340 Pa and subsequent pressure changes of 20, 40 and 80 Pa, respectively. These interference fringes characterize loci of equal displacement. In spite of interindividual variations of the central fringe pattern some basic types can be differentiated: round, oval, drop-like, double-centers, symmetrical as well as unsymmetrical and irregular forms. The peripheral fringe patterns of the cornea can be described by 3 basic types, even taking into account individual variations: circular, circular with an irregular component and irregular. The precision of the method allows to visualize minute local elasticity differences. Results of these investigations do not support the assumption, that the center of the cornea has a higher elasticity than peripheral regions in general. These elasticity differences between central and peripheral areas vary between individual corneas for small intraocular pressure changes at a basic pressure of ca. 10 mm Hg (1340 Pa).

Animals↗
PubMed1992

[Results of surgical treatment of intracranial aneurysms].

In the years 1986-1990 in the Department of Neurosurgery Military Hospital in Bydgoszcz 61 patients were treated surgically for intracranial aneurysms. Good results were obtained in 60.7% of cases and bad in 21.3%. Death from extracranial causes occurred in 6 cases. The number of past bleedings from the aneurysms, the clinical state of the patients, the timing of the operation, intraoperative rupture of the aneurysms were factors having a significant unfavourable influence on the early postoperative results.

Adolescent↗
PubMed1992

[Epidural hematoma with unilateral exophthalmos].

A case of epidural haematoma in the fronto-temporo-parietal region with ipsilateral exophthalmus is presented. In the light of 10 cases reported in literature and one own case, and on the basis of neuroanatomical data the possible causes of this rare sign are discussed. The aetiology of this exophthalmus is still unclear and subject to discussion.

Accidental Falls↗
PubMed1992

[Holographic analysis of displacement of the bovine cornea after disruption of intact structures].

Displacement of the surface of the cornea of bovine eyes after disruption of intact structures was investigated by means of holographic interferometry. Double-T-incisions of different depths were made with a diamond knife. Starting at about 80% of the incision depth there is a change in the central holographic interference fringe pattern. These effects can be clearly demonstrated by means of double-exposure holographic interferometry and real-time holographic interferometry. The stability of an existing corneal scar was analyzed by double-exposure holographic interferometry. The region of the scar showed a higher density of holographic interference fringes compared with the non-affected corneal areas, indicating a higher degree of elasticity. All eyes were investigated at an intraocular pressure of 1340 Pa (about 10 mmHg) and an intraocular pressure change of 10 Pa and 20 Pa. Further potential ophthalmic applications of holographic interferometry are discussed.

Animals↗
PubMed1979

Endplates after esterase inactivation in vivo: correlation between esterase concentration, functional response and fine structure.

Mouse sternomastoid muscles were incubated with diisopropylfluorophosphate (DFP) in vivo, and the time course of recovery was studied using histochemistry, EM autoradiography and physiology. We found that: (1) the ability of the muscle to sustain tetanus in response to nerve stimulation is eliminated when the esterases at the neuromuscular junctions are saturated with DFP. This ability is regained partially when less than 10% of the DFP-binding sites have recovered. (2) There is a positive correlation between the frequency of stimulation at which the tetanic response can be maintained and the extent of acetylcholinesterase (AChE) recovery. (3) Tetanic responses at fusion frequency (about 100 Hz) appear indistinguishable from controls with only about 25% of normal AChE. (4) Butyrylcholinesterase (BuChE) possibly of Schwann cell origin recovers more rapidly than does AChE. (5) The muscle shows fine structural changes involving Z band dissolution and the breakdown of sarcoplasmic reticulum within hours after esterase inactivation. (6) This myopathy reaches a peak at three days after esterase inactivation and is almost fully recovered by two weeks. (7) It can be eliminated if, at the time of esterase inactivation, the nerve is cut or the acetylcholine receptors at the endplate are inactivated by alpha-bungarotoxin. We suggest that the myopathy, seen after DFP, is mediated by Ca2+ fluxes due to prolonged action of acetylcholine (ACh) in the absence of esterases.

Acetylcholinesterase↗
PubMed1978

Acetylcholinesterase in the fast extraocular muscle of the mouse by light and electron microscope autoradiography.

The distribution of acetylcholinesterase (ACHe) in the twitch fibers of the extraocular muscles of the mouse was examined by light and electron microscope autoradiography after labeling with radioactive diisopropyl fluorophosphate (DFP) with, and without, 2-pyridine aldoxime methiodide (2-PAM) reactivation. The values obtained were compared with those previously reported for the diaphragm and sternomastoid muscles. The extraocular muscles were studied because they differ from the other two muscles in that they are among the fastest of the mammalian muscles, yet their endplates have sparse junctional folds. They could thus provide information on the extent to which ACHe concentration is an invariant feature of endplate morphology and what, if any aspects may be related to their fast speed of response. We found, using light microscope autoradiography, that in the twitch fibers of the extraocular muscle, there is n average of 6.4 +/- 2.1 X 10(7) DFP-binding sites per endplate, of which 29% (1.8 X 10(7)) are reactivated by 2-PAM and are thus AChe. The morphology of the extraocular endplates allowed us to conclude, on statistical grounds, that the AChe site are probably localized not only along the surface area of the postjunctional membrane (PJM) but also along the surface of the presynaptic axonal membrane. Based on this localization, we calculate 7,800 DFP sites and 2,500 2-PAM-reactivated sites/micron 2 of surface area of pre-and postjunctional membrane. This stacking density of DFP-binding sites per surface area of membrane ( probably in the overlying sheets of basal lamina) is very similar to that in the diaphragm and sternomastoid muscles.

Acetylcholinesterase↗
PubMedDate not supplied

[Unilateral exophthalmos during the course of epidural hematoma].

Based on 10 cases in the literature and one of our own a review is made on the occurrence of an association of an intracranial epidural haematoma with unilateral exophthalmos. The possible pathogenesis of this infrequent phenomenon is discussed.

Adult↗