Biomedical subjects

H Schmidek

Publications and source records attributed to H Schmidek.

3 recordsLinked to original sources

PubMed1986

Reactivity of rabbit basilar artery to alterations in extracellular potassium and calcium after subarachnoid hemorrhage.

Hemolysis of periarterial clots after subarachnoid hemorrhage may liberate large quantities of K+ into the vicinity of cerebral blood vessels and possibly change their sensitivity to endogenous vasoactive agents. The current study examined the influence of subarachnoid hemorrhage on the sensitivity of rabbit basilar arterial segments to K+ and Ca++. An analysis of K+ and Ca++ dose-response curves demonstrated that incubated arterial segments isolated from animals with subarachnoid hemorrhage were substantially more sensitive to these cations than were corresponding controls. We speculate that chronically elevated K+ levels in areas of periarterial clot lysis or brain ischemia might initiate vascular smooth muscle depolarization and vasospasm. Our data provide additional rationale for the use of calcium channel blockers in preventing or treating vasospasm in cases of subarachnoid hemorrhage.

Animals↗

PubMed1979

Pineoblastoma: an electron microscopic study.

The ultrastructure of a human pineoblastoma is described. Tumor cells formed nests, palisading row and rosettes. Cells within nests were undifferentiated. Palisade and rosette forming cells had polarized cytoplasms and showed signs of differentiation and surface membrane specialization which included surface end-bulb-like protrusions of the cytoplasm, bulbous cilia with a 9 + 0 microtubular skeleton, and blunted microvilli. In the cytoplasm of tumor cells there were characteristic granular bodies, whorls of smooth endoplasmic reticulum and annulate lamellae. Some of these findings appear to be unique to pineal tumor and are reminiscent of photoreceptor cells in the pineal glands of lower vertebrates and human fetal pineal glands.

Brain Neoplasms↗

PubMed1977

Insulin-dependent diabetes mellitus. Sudden onset following hypophysectomy in an acromegalic patient.

A euglycemic woman with acromegaly contracted conspicuous hyperglycemia two hours following transphenoidal hypophysectomy. Insulin therapy was initiated and has by necessity been continued. The development in the immediate postoperative period of blood glucose levels ranging from 300 to 500 mg/dl was totally unexpected, as the levels on the preoperative oral glucose tolerance test were normal. No explanation for this sudden development of hyperglycemia is apparent. Therefore, frequent monitoring of the blood glucose level is necessary in all acromegalic patients following hypophysectomy, even if they are euglycemic prior to surgery.

Acromegaly↗