Gait abnormalities in peroneal nerve paralysis and their corrections by orthoses: a biomechanical study.

Stroke, brain injury, incomplete spinal cord injuries, and peripheral neuropathies frequently result in dysfunction of the foot dorsiflexors and evertors. A controlled examination of aspects of these disabilities was conducted with normal volunteers who underwent a temporary peroneal nerve block. The effects of peroneal nerve paralysis were analyzed to quantitatively describe the resulting gait abnormalities and to assess the effectiveness of orthoses in restoring a normal gait pattern.

Cognitive spatial processing and the regulation of posture.

Subjects performed the Brooks (1967) spatial and nonspatial memory tasks either while sitting or while maintaining a difficult standing balance position. The balance task disrupted spatial but not nonspatial memory performance. Balance steadiness during spatial and nonspatial memory conditions did not differ.

Ankle-foot orthoses: effect on gait abnormalities in tibial nerve paralysis.

To study the biomechanical effects of gastrocnemius-soleus dysfunction and its potential remediation, the gait patterns of six able-bodied young adults were analyzed before and after induced temporary tibial nerve paralysis. Ambulation with the tibial nerve block was performed with and without the assistance of an ankle-foot orthosis (AFO) with a rigid anterior stop adjusted to either 5 degrees plantarflexion or 5 degrees dorsiflexion. The gait abnormalities resulting from tibial nerve paralysis include delayed advancement of the center of pressure, delayed ipsilateral heeloff and early contralateral heelstrike, decreased steplength, decreased ankle dorsiflexion moment, and increased knee flexion moment.

Oxygen dependent lactate utilization by Lactobacillus plantarum.

Lactobacillus plantarum P5 grew aerobically in rich media at the expense of lactate; no growth was observed in the absence of aeration. The oxygen-dependent growth was accompanied by the conversion of lactate to acetate which accumulated in the growth medium. Utilization of oxygen with lactate as substrate was observed in buffered suspensions of washed whole cells and in cell-free extracts.

Gait abnormalities in tibial nerve paralysis: a biomechanical study.

Gastrocnemius-soleus dysfunction is a frequent result of cauda equina lesions and peripheral neurophathies and of stroke and brain injury. Temporary tibial nerve paralysis constitutes a comparable laboratory condition which allows the controlled examination of aspects of these disabilities. The biomechanical effects of temporary tibial nerve paralysis in six normal young adult volunteers were examined to quantitatively define the gait abnormalities resulting from gastrocnemius-soleus paralysis and to provide a basis for the assessment of the effectiveness of different orthotic designs in restoring a normal gait pattern.

Can Ib axons be selectively activated by electrical stimuli in human subjects?

A tendon-vibration technique, used to raise the electrical threshold of muscle spindle Ia afferent fibers above that of Golgi tendon organ Ib afferent fibers in animals, was tested on human subjects. After prolonged tendon vibration, electrical stimulation of the posterior tibial nerve was ineffective or markedly less effective in eliciting Hoffmann (H-) reflexes in the soleus muscle at previbration threshold intensities. With stimulus intensity held constant at values between 1.

Correlation of oxygen utilization and hydrogen peroxide accumulation with oxygen induced enzymes in Lactobacillus plantarum cultures.

Two strains of Lactobacillus plantarum accumulated H2O2 when grown aerobically in a complex glucose based medium. The H2O2 accumulation did not occur immediately on exposure of the culture to O2 but was delayed for a time which, in the case of one strain, was dependent on the amount of inoculum used to seed the culture. The accumulation was always preceded by an increase in the rate of O2 utilization by the cultures.

Artemia hemoglobins. Increase in net synthesis of the beta-polypeptide (relative to the alpha-polypeptide) in hypoxia.

Previous studies have shown that in the brine shrimp there are three dimeric hemoglobins with polypeptide composition alpha 2, alpha beta, beta 2. Concentrations of the alpha- and beta-polypeptides increase in hypoxia. We now report a two-dimensional electrophoretic method for assay of radiolabelled polypeptides in each hemoglobin.

Purification and properties of retinol- and retinoic acid-binding proteins from a transplantable mouse colon tumor.

Cellular retinol-binding protein and retinoic acid-binding protein, the possible mediators of the action of retinoids in epithelial differentiation and control of tumorigenesis, have been reproducibly purified from mouse colon tumor 26, and some of their properties were studied. The main steps of purification involved acid-precipitation, DEAE-Sephadex, CM-cellulose and Sephadex G-100 chromatography. About 2 mg of the binding proteins were isolated from 60 g tumor.

Retinoic acid-binding protein in experimental and human colon tumors.

Retinoic acid-binding protein is present in metastatic murine colon tumors as well as in Lewis lung tumors and in lungs and brains of mice bearing these tumors; however, this protein is below the limits of detection in weakly-metastatic carcinomas and in normal lung, colon, or brains. These observations are interesting since they concern the possibility of measuring the binding protein levels of colon tumors in clinical specimens as biochemical markers in human malignancy. A total of thirty-three human colon tumors and related materials were analyzed for the presence of the binding protein.

Enteritis cystica profunda.

In addition to hamartomatous polyps of the small intestine, a patient with Peutz-Jeghers disease had gross and microscopic lesions of the ileum that were analogous to colitis cystica profunda in the large intestine and rectum. To the authors' knowledge, this is the first such case in an adult to be reported. They suggest the designation, "enteritis cystica profunda.

Role of caloric intake in the weight loss after jejunoileal bypass for obesity.

Sixty-five patients were studied prospectively after jejunoileal bypass for obesity. Dietary intake pre- and postoperatively was measured either directly by weighing food or by a research dietary history. Of 65 measurements, 59 were made at least 6 months after operation, when over 75% of weight loss had been achieved.

Prostaglandins E and F in endocrine diarrheagenic syndromes.

The role of prostaglandins in endocrine diarrheagenic syndromes was evaluated by measuring peripheral concentration of immunoreactive PGE and PGF in patients with non-endocrine diarrhea as well as those with the Zollinger-Ellison (Z-E) syndrome, MCT, carcinoid tumors and the WDHA syndrome. In 21 normals, PGE and PGF levels averaged 272 +/- 18 and 119 +/- 14 pg/ml, respectively. Twenty eight patients with diarrhea of non-endocrine origin (mainly inflammatory bowel disease) had levels indistinguishable from normal, i.

Failure of complex supplementation of minimal cultures to elicit a shift-up response in Pseudomonas putida.

The addition of complex supplements (particularly amino acids) to cultures of Pseudomonas putida growing on a good carbon source did not result in a substantial increase in the growth rate. Amino acids entered the cells within 30 s of addition and reached significant internal pool concentrations. Endogenous amino acid biosynthesis was quickly inhibited (about 75%), with a substantial sparing of the original carbon source.

Regulation of arginine and pyrimidine biosynthesis in Pseudomonas putida.

Repression of biosynthetic enzyme synthesis in Pseudomonas putida is incomplete even when the bacteria are growing in a nutritionally complex environment. The synthesis of four of the enzymes of the arginine biosynthetic pathway (N-acetyl-alpha-glutamokinase/N-acetylglutamate-gamma-semialdehyde dehydrogenase, ornithine carbamoyltransferase and acetylornithine-delta-transaminase) could be repressed and derepressed, but the maximum difference observed between repressed and derepressed levels for any enzyme of the pathway was only 5-fold (for ornithine carbamoyltransferase). No repression of five enzymes of the pyrimidine biosynthetic pathway (aspartate carbamoyltransferase, dihydro-orotase, dihydro-orotate dehydrogenase, orotidine-5'-phosphate pyrophosphorylase and orotidine-5'-phosphate decarboxylase) could be detected on addition of pyrimidines to minimal asparagine cultures of P.

Regulation of catalase synthesis in Salmonella typhimurium.

The specific activity of catalase in Salmonella typhimurium and other enteric bacteria decreased during the logarithmic phase of growth and increased at the onset and during the stationary phase. The increase in catalase synthesis at the end of the exponential phase in S. typhimurium cells coincided with the lowest pH value reached by the culture.

Polarographic assay of hydrogen peroxide accumulation in microbial cultures.

A method is described for determining low concentrations of hydrogen peroxide by using a polarographic oxygen electrode to measure the oxygen released into solution on addition of catalase. A sample can be assayed directly without prior manipulation in 3 min. The method is capable of assaying hydrogen peroxide concentrations as low as 7 muM.

Cold-sensitive mutation of Pseudomonas putida affecting enzyme synthesis at low temperature.

A cold-sensitive mutant of Pseudomonas putida has been isolated which grows normally at 30 C but is unable to grow on mandelate as a source of carbon at 15 C. The mutation results in the inability of the strain to carry out the reaction catalyzed by cis,cis-muconate lactonizing enzyme at low temperature and must lie in the structural gene for that enzyme, because the mutant enzyme produced at 30 C shows altered thermal stability. The mutant enzyme is not intrinsically cold-labile, nor is it cold-labile at the moment of synthesis.