Eye velocity responsiveness and its proprioceptive component in the floccular Purkinje cells of the alert pigmented rabbit

Summary Eye velocity responsiveness of floccular Purkinje cells was studied in alert, pigmented rabbits. Conjugate horizontal eye nystagmus was elicited by application of electric pulse trains (10–50 A, 30 c/s) to the optic tract through chronically implanted electrodes. Purkinje cells were sampled with an extracellular microelectrode from the flocculus, and their involvement in different oculomotor functions was specified by electrical stimulation at their recording sites. At those sites where abduction of the ipsilateral eye was elicited, the discharge frequency of simple spikes usually increased during slow eye movement to the ipsilateral side and decreased during eye movement to the contralateral side in nystagmus and after-nystagmus. Within a limited range, the discharge frequency increased linearly with eye velocity, at an average rate of 1.6 impulse s^–1/degree s^–1. An opposite directional specificity (decrease in ipsilateral and increase in contralateral eye movement) and directional nonspecificity were common at other floccular sites where local stimulation elicited downward or no eye movement. Retrobulbar anesthesia of proprioceptive afferents from one eye reduced the eye velocity responsiveness of Purkinje cells in the ipsilateral flocculus by 31%, but did not affect their responsiveness in the contralateral flocculus. These observations indicate that eye velocity input to the rabbit flocculus arises partly from peripheral receptors but mainly from the central oculomotor system, and that responsiveness of Purkinje cells to the input is organized specifically according to their functional involvement.This work was supported by a grant from the Japanese Ministry of Education, Science and Culture (57770092)     

Gorlin syndrome with ulcerative colitis in a Japanese girl

We present the case of a 14-year-old Japanese girl who had both Gorlin syndrome and ulcerative colitis. She had complained of blood stools for 6 months and severe scoliosis from her infancy. Physical examination revealed multiple nevi, palmar and plantar pits, jaw cysts, and calcification of the falx cerebri, leading to the diagnosis of Gorlin syndrome. Total colonoscopy revealed an edematous and spotty bleeding mucosa extending from the anus to the transverse colon. Histological examination was also compatible with ulcerative colitis. Thus, we diagnosed her as having Gorlin syndrome with ulcerative colitis. Gene analysis revealed a mutation, 1247InsT, in the human patched gene (PTCH), resulting in the truncation of PTCH protein. Since Gorlin syndrome and ulcerative colitis are rare disorders in childhood, this association is interesting, suggesting a correlation between the hedgehog signaling and intestinal disorders.     

Specific tension of elbow flexor and extensor muscles based on magnetic resonance imaging

Series cross-section images of the upper extremity were obtained for four men by magnetic resonance imaging (MRI) and anatomical cross-sectional areas (ACSA) of elbow flexor muscles [biceps brachii (BIC), brachialis (BRA), brachioradialis (BRD)] and extensor muscles [triceps brachii (TRI)] were measured. Physiological cross-sectional area (PCSA) was calculated from the muscle volume and muscle fibre length, the former from the series ACSA and the latter from the muscle length multiplied by previously reported fibre/muscle length ratios. Elbow flexion/extension torque was measured using an isokinetic dynamometer and the force at the tendons was calculated from the torque and moment arms of muscles measured by MRI. Maximal ACSA of TRI was comparable to that of total flexors, while PCSA of TRI was greater by 1.9 times. Within flexors, BRA had the greatest contribution to torque (47%), followed by BIC (34%) and BRD (19%). Specific tension related to the estimated velocity of muscle fibres were similar for elbow flexors and extensors, suggesting that the capacity of tension development is analogous between two muscle groups.     

Expression and immunogenicity of hemagglutinin A from Porphyromonas gingivalis in an avirulent Salmonella enterica serovar typhimurium vaccine strain

Porphyromonas gingivalis is a major etiologic agent of periodontitis, a chronic inflammatory disease that ultimately results in the loss of the supporting tissues of the teeth. Previous work has demonstrated the usefulness of avirulent Salmonella enterica serovar Typhimurium strains as antigen delivery systems for protective antigens of pathogens that colonize or cross mucosal surfaces. In this study, we constructed and characterized a recombinant S. enterica serovar Typhimurium avirulent vaccine strain which expresses hemagglutinin A and carries no antibiotic resistance markers. HagA, a major virulence-associated surface protein, is a potentially useful immunogen that contains an antigenic epitope which, in humans, elicits an immune response that is protective against subsequent colonization by P. gingivalis. The hagA gene, including its promoter, was cloned into a balanced-lethal Salmonella vector and transferred to the vaccine strain. Heterologous expression of HagA was demonstrated in both Escherichia coli JM109 and S. enterica serovar Typhimurium vaccine strain chi4072. The HagA epitope was present in its native configuration as determined by immunochemistry and immunoelectron microscopy. Purified recombinant HagA was recognized by sera from mice immunized with the S. enterica serovar Typhimurium vaccine strain. The HagA-specific antigen of the vaccine was also found to be recognized by serum from a periodontal patient. This vaccine strain, which expresses the functional hemagglutinin protein, induces a humoral immune response against HagA and may be useful for developing a protective vaccine against periodontal diseases associated with P. gingivalis.     

Generation of fractal patterns for probing the visual memory.

The effective use of computer-generated pictures as a trial-unique probe for studying the visual memory is described. The shape of the pattern is determined by means of a fractal algorithm with pseudorandom parameters. This method enables us to easily obtain thousands of moderately complex and sufficiently diversified pictures in series from a given number which serves as the seed of a pseudorandom number generator. We can thereby create a new and unique set of pictures if a new seed is given, as well as retrieve exactly the same pictures in the same sequence as when the original seed is given. These properties eliminate the demand for the massive memory space in a computer otherwise needed to store the entire set of stimulus pictures.     

Effect of isometric and isokinetic muscle training on static strength and dynamic power

Summary This study investigated whether isokinetic strength training might induce changes in static and dynamic power already achieved as a result of isometric strength training. The subjects were twelve males. The isometric strength and dynamic power of elbow flexors were tested by means of an electric dynamometer and fly-wheel every two weeks. During the first 8 weeks all subjects trained the elbow flexors isometrically at four different positions of elbow joints. This training produced 27–36% gains in isometric strength and 34–46% in power. Thereafter the subjects were divided into two groups: the FG group who trained isokinetically at a fast velocity of 157·s^–1, and the SG group at slow velocity of 73·s^–1. After 6 weeks of training, the FG group produced a significant gain in power with light equivalent masses and the SG group did so with heavy equivalent masses. Neither group showed change in isometric strength.     

Infantile XX male: A case report

A case of infantile XX male syndrome with bilateral scrotal testes and penoscrotal hypospadias is presented. No evidence of XX/XY mosaicism or Y chromatin was obtained in preparations from cultures of the peripheral blood, skin fibroblast, or other tissues. Although true hermaphroditism was suspected, exploration of the bilateral gonadal structures failed to detect the presence of ovarian structures, either grossly or microscopically. Furthermore, exploratory laparotomy revealed no Mullerian structures. The difficulty of early diagnosis of XX males in infancy is emphasized.