Post-translational modifications of apolipoprotein A-I and Po proteins in the avian peripheral nerve.

Apolipoprotein A-I (apo A-I), a soluble lipid transporter, and Po, the major glycoprotein of myelin, are actively synthesized during myelination. To explore the status of post-translational modifications of these proteins in the avian PNS during rapid myelination, endoneurial slices from one day old chick sciatic nerves were incubated with various radioactive precursors that could serve as indicators of such processes. The proteins were isolated from the incubation medium (secreted fraction), the 1% Triton-X-100-soluble intracellular-endoneurial (intracellular) fraction, and myelin-related and purified compact myelin fractions by immunoprecipitation with monospecific anti-apo A-I and or anti-Po antisera. Our results demonstrated that secreted apo A-I is fatty acylated, but not phosphorylated or sulfated. Avian Po protein was phosphorylated by a phorbol ester sensitive protein kinase. Sulfation, as well as fatty acylation, of avian Po protein was observed in organ culture using highly sensitive methods of detection. These results indicate that fatty acylation of secreted apo A-I and phosphorylation, sulfation and fatty acylation of Po have been conserved during evolution, and that these post-translational modifications may play a common function in various species.

Reduced variance of latencies in pudendal evoked potentials after normalization for body height.

The value of the Somatosensory Evoked Potentials (SEP) in the assessment and detection of neurological disorders could be considerably enhanced if the normative standards of (SEP) characteristic parameters were normalized taking into account all other systematic sources of variance. The present study examines the influence of body height on the peak and interpeak latencies of the pudendal somatosensory evoked potentials. We examined the peak latency (L1) of the evoked potential recorded at the L1 vertebra and the onset latency (ONc) of the cortical evoked potentials, after stimulation of the pudendal nerve, as a function of body height in 40 normal male subjects (age 20-40 years). Significant positive correlation was found between both (ONc) latency and ONc-L1 interpeak latency and body height (H). Assuming that the latter is proportional to the length of the neural pathways, the experimental data were fitted using a theoretical model representing the conduction in the sensory neuraxis as a function of body height. Using the estimated fitting functions, we normalized our data with regard to a typical value of body height. The normalized values of the aforementioned latencies reveal a significantly reduced variance, as compared to the original ones, and consequently their diagnostic importance is significantly increased. Similar procedures applied to the L1 (spinal) latencies and the latencies of the bulbocavernosus reflex (BCR) reveal no correlation with body height and this is discussed on the basis of neuroanatomical considerations.

Myelolipoma of the adrenal gland.

We report 2 cases of large adrenal myelolipoma. Although their fatty nature was found by a CT scan and there was no endocrine activity, surgery was done because of their size and the caused discomfort.

Aspects concerning posterior urethral valves.

Twenty-six boys were evaluated and treated for posterior urethral valves. At the time the valves were diagnosed unilateral or bilateral vesicoureteral reflux was present in 58% of the ureters and 69% of the children, while dilatation of the upper urinary tract was present in 88% and 92%, respectively. There was a variety of symptoms and signs, but the most prominent in neonates and infants were vesical urine retention, palpable kidneys and failure to thrive, whereas in the older children voiding dysfunction, incontinence and urinary infection were the most common. Twenty-four out of 26 boys were managed by primary valve ablation and in 62.5% of them this type of treatment was adequate in resolving or sufficiently improving clinical manifestations and roentgenologic findings, requiring no further management. Urinary diversion in the form of vesicostomy and cutaneous ureterostomy was preserved for those patients who did not improve with valve ablation alone. The current aspects concerning posterior urethral valves are also discussed.