On spinal osteochondromas.

Osteochondromas (or osteocartilaginous exostoses) make up about 30% to 40% of benign bone tumors. Most are solitary lesions but some are multiple, usually with autosomal dominant inheritance. From 1% to 4% of osteochondromas occur in the spine, where they can cause a variety of signs and symptoms, including those of spinal cord or spinal root compression. The authors present five patients with osteochondromas of the spine and review the findings together with those of over 130 cases reported since 1907. The cases were divided into: 1) spinal osteochondromas in patients with multiple osteochondromas, and 2) solitary osteochondromas occurring in the spine. The age (mean +/- standard error of the mean) of patients in the first group was 21.6 +/- 1.8 years compared to 30.0 +/- 2.1 years for those in the second group (p less than 0.02). There was a significant male predominance overall (M:F = 2.5:1; p less than 0.0005). In both groups, one-half of the lesions involved the cervical spine. Symptoms are caused by pressure on adjacent structures. Spinal cord compression was reported more than twice as frequently in the multiple osteochondroma group as in the single osteochondroma group (77% vs 33%; p less than 0.0005). Computerized tomography (CT) is the imaging procedure of choice. In both groups, the majority of surgically treated patients (90% and 88%, respectively) improve, with about three-quarters of the improved patients having no residual disease or only minor deficits.     

Cortical neurons: isolation of contrast gain control.

The selectivity of cortical neurons remains invariant with contrast, even though the contrast-response function saturates. Both the invariance and the saturation might be due to a contrast-gain control mechanism. To test this hypothesis, a drifting grafting was used to measure the contrast-response function, while a counterphase grating was simultaneously presented at the null position of the receptive field (where it evokes no response at any contrast). When the contrast of the counterphase grating increased, the contrast-response function shifted primarily to the right. This result is consistent with the hypothesis that there is a fast-acting gain-control mechanism which effectively scales the input contrast by the average local contrast.     

Number of Edb motor units estimated using an adapted multiple point stimulation method: normal values and longitudinal studies in ALS and peripheral neuropathies.

OBJECTIVE: To validate the adapted multiple point stimulation (AMPS) method to estimate the number of motor units (MUNE) from the extensor digitorum brevis (Edb) muscle. METHODS: Twenty controls (10 young and 10 old) were examined on both sides and 10 patients with amyotrophic lateral sclerosis (ALS) and 5 with acute peripheral neuropathy (PN) were examined longitudinally on one side during a series of repeated electrophysiological sessions. RESULTS: In the controls, the median MUNE and size of the motor unit action potentials (S-MUAPs) were found to be age-related (411 and 70 microVms in the young group; 164 and 142 microVms in the old group; P < 0.01), with a coefficient of variation of MUNE values of 27% and 20%, respectively. In the ALS group, the median MUNE value at diagnosis was 31 (P < 0.05 vs. controls), and during a mean follow-up period of 11.5 months a continuous decrease in the MUNE value was seen, together with an initial increase, followed by a later decrease in 4 cases, in S-MUAP size. In the PN group, the MUNE value was initially similar to that in controls, but then decreased, accompanied by an increase in S-MUAP size, and then showed a progressive increase, together with a decrease in S-MUAP size. CONCLUSIONS: AMPS, a MUNE method developed in the upper extremity, also appears to be a useful procedure for quantifying changes in the MUNE value in the Edb muscle without specific software in order to study age-related changes or changes in patients with ALS or PN.     

Na+/K+-ATPase activity and GABA uptake in astroglial cell-enriched fractions and synaptosomes derived from rats in the early stage of experimental hepatogenic encephalopathy

Na+/K+-ATPase activity and GABA uptake were measured in the bulk isolated astrocytes and synaptosomes from rats in which an early, metabolic phase of hepatogenic encephalopathy (HE) was induced by the treatment with thioacetamide (TAA). Both the enzyme activity and the amino acid neurotransmitter uptake were increased above control in the astroglial fraction but remained unaffected in synaptosomes. The results lend support to the earlier observations that the astrocytes are the primary target cells in HE. Furthermore, they may be interpreted as indicating that the early astroglial reaction to HE comprises stimulation of the astrocytes' function, especially concerning clearance of K+ ions and neurotransmitters from the extracellular space of CNS.     

Cauliflower mosaic virus gene I product detected in a cell-wall-enriched fraction

Gene I product of cauliflower mosaic virus was immunodetected in a cell-wall-enriched fraction from infected turnip leaves in addition to its detection in viroplasms and replication complexes. The immunoreaction was carried out with an antiserum raised against a 15 amino acid long synthetic peptide corresponding to the carboxy-terminus of potential gene I protein (P1). The presence of P1 in different subcellular fractions was investigated as a function of time during viral multiplication. At late infection times, P1 was found only in the cell-wall-enriched fraction.     

Palisaded encapsulated neuroma: an immunohistochemical study

Ten palisaded neuromas of the skin were studied immunohistochemically for the presence of S-100 protein, epithelial membrane antigen, neurofilaments, glial fibrillary acidic protein, and positivity with the Leu-7 monoclonal antibody. In all cases, the fascicles of tumor cells were positive for S-100 protein and negative for epithelial membrane antigen; the tumor capsules were negative for the former in all cases but positive for the latter in seven of ten cases. In three lesions, epithelial membrane antigen-positive cells formed sheaths around fascicles of tumor cells. Axons were demonstrated by anti-neurofilament antibody in seven lesions. None of the lesions stained for glial fibrillary acidic protein. All of them showed positivity with the Leu-7 antibody, which stained both tumor spindle cells as well as membranous profiles consistent with myelin sheaths. These results indicate that the tumor is composed of cells of schwannian differentiation whereas the capsule and sheaths surrounding intratumoral fascicles are of perineurial origin. They also indicate the presence of axons, some of which are myelinated. Our findings support the concept of a close relationship between palisaded and traumatic neuroma.     

The Impact of Diet on Urinary Risk Factors for Cystine Stone Formation

Despite the importance of dietary management of cystinuria, data on the contribution of diet to urinary risk factors for cystine stone formation are limited. Studies on the physiological effects of diet on urinary cystine and cysteine excretion are lacking. Accordingly, 10 healthy men received three standardized diets for a period of five days each and collected daily 24 h urine. The Western-type diet (WD; 95 g/day protein) corresponded to usual dietary habits, whereas the mixed diet (MD; 65 g/day protein) and lacto-ovo-vegetarian diet (VD; 65 g/day protein) were calculated according to dietary reference intakes. With intake of the VD, urinary cystine and cysteine excretion decreased by 22 and 15%, respectively, compared to the WD, although the differences were not statistically significant. Urine pH was significantly highest on the VD. Regression analysis showed that urinary phosphate was significantly associated with cystine excretion, while urinary sulfate was a predictor of cysteine excretion. Neither urinary cystine nor cysteine excretion was affected by dietary sodium intake. A lacto-ovo-vegetarian diet is particularly suitable for the dietary treatment of cystinuria, since the additional alkali load may reduce the amount of required alkalizing agents.     

Concept for a health care economic evaluation of short- and long-term costs and effectiveness parameters of an expanded ambulatory psychosomatic rehabilitation program

There are only few ambulatory rehabilitation concepts for mothers with psychosomatic disorders (prevalence 5%). Also, only little is known about the evaluation of these programmes. This study compares the socioeconomic evaluations of an ambulatory rehabilitation programme with a post-assistance programme and one without a post-assistance programme. The superior programme should be determined by weighing all relevant costs and benefits. The intensive phase of the ambulatory rehabilitation programme consists of an eight-week treatment with group, single, body and art therapy. The post-assistance programme spans a period of nine-months with 36 sessions of psychoanalytic group therapy. The evaluation of both programme alternatives is made by with the evaluation tool of socioeconomic analyses. For consideration and pricing of costs all direct medical costs, direct non-medical costs and indirect costs are being monitored. Outcomes assessment is realised by cost-effectiveness analysis, cost-utility analysis and cost-benefit analysis. Utilisation of the health care system is being assessed with questionnaires. Measurements are being performed at the beginning and the end of the rehabilitation programme and three, six, nine and twelve months later. Mothers with children aged six years and younger and suffering from various psychosomatic disorders were included in this study. The costs identified for the rehabilitation programme are DM 5571.10 (intensive care and post-assistance programme) and DM 1512.40 (intensive care) per patient. Further progress of the study will show if future cost will differ between the two alternatives. For the comparison of both alternatives all costs will be linked with outcomes. It remains to be seen that additional costs of the post-assistance programme will be compensated with positive outcomes. A sensitivity analysis will show if variation of assumptions will influence the cost-benefit-ratio of the different alternatives.