Circulating tumor-associated antigen detected by the monoclonal antibody HMFG2 in human epithelial ovarian cancer

A radioimmunometric sandwich assay for the tumour-associated antigen defined by the monoclonal antibody (MAb) HMFG2, has been used to measure serum levels of the antigen in 76 healthy controls, 38 ovarian carcinoma patients pre-operatively, 98 patients 2 to 6 weeks after surgery and 36 patients at relapse or in complete remission at 12 months. HMFG2 antigen levels were elevated in 33% of stage-I and 62% of II-IV patients pre-operatively; they reflected bulk of disease post-surgically and were significantly higher in patients in relapse than in those who were in complete remission. HMFG2 antigen levels predicted the clinical course of disease in the majority of patients.     

Tissue aluminum concentrations stability over time, relationship to age, and dietary intake

Aluminum concentration was measured in serum, whole blood, hair, and urine by neutron activation analysis. Seventy-six nondemented subjects were investigated. Not all assays were done on all subjects (e.g., serum aluminum on 76 subjects, whole blood aluminum on 42 subjects), but tissue aluminum concentrations were estimated on more than one occasion on 32 subjects. The mean +/- SD aluminum concentration in serum was 0.219 +/- 0.063 micrograms/ml (N = 76), in whole blood 0.368 +/- 0.091 micrograms/ml (N = 42), in urine 0.092 +/- 0.076 micrograms/ml (N = 42), and in hair 6.42 +/- 2.22 micrograms/g (N = 42). Using product moment correlation coefficient there was no significant correlation between age and tissue aluminum concentrations, nor between dietary intake of aluminum and tissue aluminum. The tissue aluminum concentrations were not stable over time even when dietary intake was constant. Tissue aluminum concentrations were measured in 14 patients after 7 days of dietary control and repeated approximately 6 weeks later, again after 7 days of dietary control. There was no significant correlation between the two estimations in any tissue measured. These results suggest that raised tissue aluminum concentrations reported in Alzheimer's disease are not an exaggeration of a normal ageing process, are not likely to be simply secondary to increased dietary aluminum intake, and that Alzheimer's disease does not represent the chronic toxic effect of moderately raised aluminum levels at the upper end of the normal distribution.     

Unidentified neuroglia potentials during propagated seizures in neocortex

Cortical surface and intracellular recording of silent cells (neuroglia) was carried out in the pericruciate cortex of cats during propagated seizures produced by repetitive stimulation of the surface of the opposite homotopic neocortex. The membrane characteristics of these cells were similar to neuroglial cells studied in leech, amphibian, and rat optic nerves, tissue culture, and mammalian cerebral cortex. By varying the parameters of transcallosal stimulation, it was possible to obtain either minor or major propagated seizures. All cells with resting membrane potentials (RMP) greater than 30 mv recorded during minor propagated seizures exhibited a depolarizing response (5–14 mv) during the seizure episode followed by a postictal hyperpolarizing response (1–9 mv) and a slow return to the original resting level. The peak amplitude of the depolarizing response was proportional to the cell's RMP and the amplitude of the seizure waves in the EEG. During major propagated seizures, an augmentation of the depolarizing response to 16–30 mv and the hyperpolarizing response to 10–15 mv was noted. A membrane conductance change during these events was not observed. During major propagated seizures, an increase in [K⁺]_o over the resting [K⁺]_o was calculated to be 10 meq/liter. However, the level of [K⁺]_o reached in the extracellular clefts was probably much higher than this calculated value for reasons which are discussed. A model for seizure propagation is presented. The postictal hyperpolarization most likely represents the effect of a K⁺-sensitive electrogenic pump in the glial membrane.     

A preliminary description of the regeneration of optic nerve fibers in a reptile, Vipera aspis

Crushing or freezing the optic nerve of the viper leads initially to the anterograde degeneration of the optic nerve fibers and to an extensive retrograde demyelination process associated with the degeneration of some retinal ganglion cells. By the 45th postoperative day, regenerating unmyelinated axons can be identified in the damaged region of the optic nerve. These fibers reach the chiasm and the marginal optic tract by the third postoperative month. The radioautographic tracing method shows that some nuclei of the primary visual system begin to be reinnervated by about the 5th postoperative month; this reinnervation was not, however, completely restored in those specimens with the longest postoperative survival of 220 days.     

Hemispheric asymmetries in feature integration during visual word recognition

Although the definitive source of the left hemisphere's superiority for visual word recognition remains illusive, some argue that the left (LH) and right (RH) hemispheres engage different strategies during early perceptual processes involved in stimulus encoding. In particular, it is proposed that the LH treats a word as a unitary perceptual group whereas the RH processes the letters comprising a word as a series of individual perceptual units. The present study investigated support for this processing distinction by examining hemispheric strategies for temporal integration using Prinzmetal and Millis-Wright's (1984) feature-binding paradigm. A total of 20 participants identified the colour and identity of a target letter, presented within a three-letter word (e.g., ART) or nonword (e.g., HRF), directed to their left or right visual field. Errors were classified on the basis of whether they involved substitution of a colour present within the stimulus but at a different location (ON error), or the substitution of a colour not present within the stimulus (OFF error). As anticipated, for word stimuli there was a higher proportion of OFF errors associated with trials directed to the RH, consistent with the notion that the LH treats words as single perceptual units and is hence biased toward miscombination of perceptual information present within the stimulus. The pattern of ON errors across stimulus type provided clear evidence of RH sequential encoding effects, with the number of errors increasing markedly across the ordinal position of the letters comprising the stimulus string. As such, these data provide new evidence that the LH's advantage for visual word recognition arises, at least in part, from the ability to encode verbal stimuli as single perceptual units.