Systemic lupus erythematosus murine monoclonal DNA-binding antibodies recognize cytoplasmic and nuclear phosphorylated antigens that display cell cycle redistribution in HEp-2 cells

The immunological basis for the production of autoantibodies characteristic of systemic lupus erythematosus (SLE) against a wide range of antigens remains obscure. The specificity of (NZB x NZW)F1 (BWF1) or MRL/Mp-lpr/lpr (MRL/lpr) mouse monoclonal antibodies (mAb) was examined by immunofluorescence, immunoblotting and immunoprecipitation techniques. Using non-synchronized HEp-2 cells as substrate, the murine mAb were classified by indirect immunofluorescence into five groups on the basis of their staining patterns of subcellular components in interphase and mitotic stages of the cell cycle. The nature of the antigens recognized by the murine lupus was assessed by immunoblotting experiments in total, cytoplasmic and nuclear cell extracts from HEp-2 cells. The six antibodies used recognized in total cell extracts a range of polypeptides with apparent molecular weights from 25,000 to 210,000. Three polypeptides of 130,000, 110,000 and 45,000 MW were recognized by all six antibodies in both nuclear and cytoplasmic extracts. Immunoprecipitation of total cellular extracts labelled with [35S]methionine showed almost the same pattern as obtained in the immunoblotting assay. The labelling in vivo of HEp-2 cells with [32P], followed by the immunoprecipitation of the [32P]cell lysate showed that these mAb recognized phosphorylated proteins. The progressive decrease in reactivity of these mAb following treatment with higher concentrations of alkaline phosphatase in both [32P]cell lysate or nitrocellulose membranes indicates that these mAb recognize phosphorylated epitopes.

Brain-stem auditory evoked potentials and brain death

BAEP records were obtained from 30 brain-dead patients. Three BAEP patterns were observed: (1) no identifiable waves (73.34%), (2) an isolated bilateral wave I (16.66%), and (3) an isolated unilateral wave I (10%). When wave I was present, it was always significantly delayed. Significant augmentation of wave I amplitude was present bilaterally in one case and unilaterally in another. On the other hand, in serial records from 3 cases wave I latency tended to increase progressively until this component disappeared. During the same period, wave I amplitude fluctuations were observed. A significant negative correlation was found for wave I latency with heart rate and body temperature in 1 case. Two facts might explain the progressive delay and disappearance of wave I in brain-dead patients: a progressive hypoxic-ischaemic dysfunction of the cochlea and the eighth nerve plus hypothermia, often present in brain-dead patients. Then the incidence of wave I preservation reported by different authors in single BAEP records from brain-dead patients might depend on the moment at which the evoked potential study was done in relation to the onset of the clinical state. It is suggested that, although BAEPs provide an objective electrophysiological assessment of brain-stem function, essential for BD diagnosis, this technique could be of no value for this purpose when used in isolation.

[Simvastatin (MK-733), a new HMG-CoA reductase inhibitor, in the treatment of hypercholesterolemia in elderly patients with atherosclerosis]

PURPOSE

To evaluate the efficacy and tolerability of simvastatin, a new and potent HMG-CoA reductase inhibitor, in the treatment of hypercholesterolemia in elderly patients.

PATIENTS AND METHODS

Twenty patients, 14 female and 6 male, aged 65 to 72 years (x = 69 +/- 3), with total cholesterol (TC) above 260 mg/dl and triglycerides below 350 mg/dl were studied. All patients presented clinical evidences of atherosclerotic disease and were followed up for 6 months. Monthly visits were required for clinical and laboratory evaluation. The initial dosage of simvastatin was 10 mg/day; dosage was titrated up to 10 mg/day or to a minimum of 5 mg/day in intervals of at least 4 weeks, in order to maintain LDL-cholesterol below 140 mg/dl. To evaluate the changes on plasma lipid levels, the mean value of determinations during the placebo baseline period was compared to the mean value of determinations during the active treatment period.

RESULTS

There were significant reductions of total cholesterol (-26.4%), triglycerides (-16.0%), LDL-cholesterol (-35.2%), VLDL-cholesterol (-15.4%), TC/HDL-C (-30.7%), and LDL/HDL-C (-39.5%). There was significant elevation of HDL-cholesterol (+5.2%), although this response was not uniform. The drug was well tolerated: only five patients reported transient clinical adverse experiences that subsided spontaneously. Two patients had elevation of CPK and one of TGP. The drug did not have to be discontinued in any case. Ophthalmological examinations performed before treatment compared to examinations at the end of the study showed no signficant alterations.

CONCLUSION

Simvastatin in elderly patients appeared to be a potent TC and LDL-C lowering drug and presented mild but significant effect on the elevation of HDL-C. There was good tolerability, with low incidence of adverse experiences. This fact is important when one considers drug therapy for hypercholesterolemia in this age group.

Brain electrical field measurements unaffected by linked earlobes reference

Recent theoretical analysis supports the possibility that using a linked earlobe reference in EEG studies might appreciatively distort the measured electrical field due to current flow over a low resistance path across the wire joining both ears. Such an effect would invalidate published quantitative EEG norms. Evidence for the balancing effect of this distortion was sought for in the EEG of 4 patients with well localized unilateral lesions, a situation in which this distortion would be most apparent. Statistical tests failed to reveal significant differences between EEGs recorded when ears were linked or unlinked. An analysis of the equivalent circuit reveals that a high skin/electrode impedance effectively makes the linked ear reference behave as an ordinary reference.