Prediction of breast tumor size by mammography and sonography--A breast screen experience.

Concise preoperative assessment of breast Tumor size is important when considering surgical approach and the staging of breast cancer. A retrospective study of 400 uni-focal, invasive ductal carcinomas compared the accuracy of sonographic and mammographic measuring modalities with histological size. Sub-groups for tumor size, type and grade, with other variables, were also considered in intra-modal correlations of lesion dimension. Mammography (R2=0.74), although slightly over estimating tumor size, appeared to be more useful than sonography (R2=0.60) following logistical analysis of the data. Correlational significance for both imaging modalities decreased for tumors larger than 20mm. Sonography under estimated lesions in over 50% of cases; the average underestimate being 9.9 mm, and ranging from 1mm to 30 mm. Consideration of both imaging measurements in cohort should improve the accuracy of radiological reporting of pre-surgical tumor size.

Chronic hypoxia potentiates capacitative Ca2+ entry in type-I cortical astrocytes.

Prolonged hypoxia exerts profound effects on cell function, and has been associated with increased production of amyloid beta peptides (A beta Ps) of Alzheimer's disease. Here, we have investigated the effects of chronic hypoxia (2.5% O2, 24 h) on capacitative Ca2+ entry (CCE) in primary cultures of rat type-I cortical astrocytes, and compared results with those obtained in astrocytes exposed to A beta Ps. Chronic hypoxia caused a marked enhancement of CCE that was observed after intracellular Ca2+ stores were depleted by bradykinin application or by exposure to thapsigargin (1 microM). Exposure of cells for 24 h to 1 microM A beta P(1-40) did not alter CCE. Enhancement of CCE was not attributable to cell hyperpolarization, as chronically hypoxic cells were significantly depolarized as compared with controls. Mitochondrial inhibition [by FCCP (10 microM) and oligomycin (2.5 microg/mL)] suppressed CCE in all three cell groups, but more importantly there were no significant differences in the magnitude of CCE in the three astrocyte groups under these conditions. Similarly, the antioxidants melatonin and Trolox abolished the enhancement of CCE in hypoxic cells. Our results indicate that chronic hypoxia augments CCE in cortical type-I astrocytes, a finding which is not mimicked by A beta P(1-40) and appears to be dependent on altered mitochondrial function.

Differential effects of unaggregated and aggregated amyloid beta protein (1-40) on K(+) channel currents in primary cultures of rat cerebellar granule and cortical neurones.

The effects of amyloid beta protein on voltage-gated K(+) channel currents were studied using the whole-cell patch-clamp technique. The 1-40 amino acid form of amyloid beta protein was applied to primary cultures of rat cerebellar granule and cortical neurones for 24 h. Both the unaggregated and aggregated forms of the peptide, which have differing biological activities, were used. In cerebellar granule neurones, 24-h pre-incubation with 1 microM unaggregated amyloid beta protein resulted in a 60% increase in the 'A'-type component of K(+) current. Increased delayed rectifier activity was Cd(2+)-sensitive and was presumed to be secondary to an increase in voltage-gated Ca(2+) channel current activity. Unaggregated amyloid beta protein had no effect on any component of the K(+) channel current in cortical neurones. One micromolar of aggregated amyloid beta protein had no effect on K(+) channel current in either cell type but reduced cell survival within 24 h as measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) assays. The unaggregated form of amyloid beta protein had no neurotoxic effects when applied to either neurone type for up to 72 h. These data indicate that the unaggregated, non-pathological form of amyloid beta protein causes changes in the ion channel function of neurones, possibly reflecting a physiological role for the peptide.

Association of Lactobacillus spp. with Peyer's patches in mice.

Sixteen strains of Lactobacillus isolated from humans, mice, and food products were screened for their capacity to associate with Peyer's patches in mice. In preliminary experiments, in vitro binding to tissue pieces was assessed by scanning electron microscopy, and it was demonstrated qualitatively that 5 of the 16 strains showed some affinity for the Peyer's patches, irrespective of their association with the nonlymphoid intestinal tissue. Lactobacillus fermentum KLD was selected for further study, since, in addition to its intrinsically high adhesion rate, this organism was found to exhibit a preferential binding to the follicle-associated epithelium of the Peyer's patches compared with its level of binding to the mucus-secreting regions of the small intestine. Quantitative assessment of scanning electron micrographs of tissue sections which had been incubated with L. fermentum KLD or a nonbinding control strain, Lactobacillus delbruckii subsp. bulgaricus, supported these observations, since a marked difference in adhesion was noted (P < 0.05). This preferential association of strain KLD with the Peyer's patches was also confirmed with radiolabeled lactobacilli incubated with intestinal tissue in the in vitro adhesion assay. Direct recovery of L. fermentum KLD from washed tissue following oral dosing of mice revealed a distinct association (P < 0.05) between this organism and the Peyer's patch tissue. In contrast, L. delbruckii subsp. bulgaricus showed negligible binding to both tissue types in both in vitro and in vivo adhesion assays. It was concluded that L. fermentum KLD bound preferentially to Peyer's patches of BALB/c mice.

Fluoxetine, electroconvulsive therapy, and prolonged seizures. Nursing assessment leads to patient safety.

The study sought to find whether the discontinuation of fluoxetine (Prozac) 14 days prior to electroconvulsive therapy (ECT) results in positive patient outcome through improved safety and if the administration of Prozac in close proximity to ECT results in prolonged seizures. Patients who had ECT with 14 days' clearance of Prozac had no prolonged seizure activity. The awareness of possible complications resulting from Prozac and ECT soon became evident among the staff, and every effort was made to communicate this. Prozac has been promoted as being safer than tricyclic antidepressants because of its low cardiac toxicity and relative safety in overdoses.