Changes in reactivity of the middle cerebral artery caused by cerebral circulation disturbances of ischemic and hemorrhagic types in rats

Reactivity of the middle cerebral artery (MCA) to serotonin was attenuated in vitro in vessels taken from rats following an audiogenic stress. The MCA reactivity to endothelin remained unchanged. Chronic cerebral ischemia diminished the 5-HT-induced contraction and the contractile responses to endothelin were enhanced. Preliminary hypoxic adaptation decreased the artery sensitivity to endothelin in ischemic animals. The findings suggest that a progressing ischemia may involve changes in reactivity of cerebral vessels whereupon hypoxic adaptation may prove to be protecting the brain from ischemia development.     

Elevated alpha-fetoprotein secondary to Hodgkin's lymphoma

We describe the case of a 26-year-old man with an elevated level of alpha-fetoprotein who had no evidence of intragonadal or extragonadal germ cell tumor. The patient was found to have Hodgkin's lymphoma within an anterior mediastinal mass. We review the significance of elevated alpha-fetoprotein levels and discuss the clinical relevance of this unusual presentation of a possible primary Hodgkin's lymphoma.     

Determination of radial growth rate of colonies of Sclerotium rolfsii F-6656 for the evaluation of culture medium, optimum incubation temperature, osmo- and halotolerance

The measurement of the colony radial growth rate (Kr) on solid medium of colonies of Sclerotium rolfsii Proimi F-6656 for the evaluation of scleroglucan production medium and other different media, incubation temperature and tolerance to diverse concentrations of sucrose and NaCl were studied. The optimum growth temperature observed was 30 degrees C. The Kr value reached on the Production Medium used (0.66 mm.h-1) showed no differences compared with those of the other media tested, indicating that all the requirements for growth were provided. Poor growth was only observed on Soil Extract Agar. The fungus tolerated concentrations of sucrose from 0.15 to 1.17 M, on both Czapek and production medium. Growth was limited by the highest concentrations of sucrose tested (0.88 and 1.17 M), as indicated by a slower increase in colony size. Addition of 0.86 M NaCl to the production medium and YM agar did not inhibit growth completely, but decreased the radial growth rate considerably (80 and 70% respectively).