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Biomedical subjects

Y Handa

Publications and source records attributed to Y Handa.

At least 37 records · Page 2Linked to original sources
PubMed1999

An approach to a muscle model with a stimulus frequency-force relationship for FES applications.

A simplified model of electrically stimulated muscle for use in applications of functional electrical stimulation (FES) is discussed in this paper. The muscle model was required to have both stimulus frequency and stimulus intensity (amplitude/width) inputs. The stimulus frequency versus force relationship of rabbit muscle was modeled first with a small number of model parameters that could be identified by simple experiments in a short time. The model identified was found to be applicable to human muscles. The frequency-force relationships of electrically stimulated fast and slow type muscles were also predicted by the model. The frequency-force model and a simplified model of muscle activation dynamics were used to construct a muscle model that described the summation of muscle contraction. The use of this model decreased the time burden on patients during parameter identification at the clinical site. The clinical applicability of these new model descriptions was suggested through computer simulations.

Animals↗
PubMed1999

Restoration of shoulder movement in quadriplegic and hemiplegic patients by functional electrical stimulation using percutaneous multiple electrodes.

The purpose of this study is to restore the motion of the paralyzed shoulder caused by upper motor neuron disorders using functional electrical stimulation (FES). Percutaneous wire electrodes were implanted into twelve muscles of the shoulder in six patients with stroke or cervical spinal cord injury. The motion of the paralyzed shoulder was controlled by a portable FES computer system, with the three standard stimulation patterns for restoring motion of 90 degrees flexion to 90 degrees horizontal abduction, 90 degrees flexion to 20 degrees horizontal adduction, and 90 degrees abduction to 90 degrees horizontal adduction. Shoulder movements were repeatedly controlled according to the created stimulation patterns in five of the patients. The two dimensional motion analyzer also confirmed shoulder control over a satisfactorily broad range of excursion. One hemiplegic patient, who was a signboard painter, had his paretic left upper extremity improved by FES, and he drew a large picture on a board with his normal right hand and, with his affected left arm against the wall, to support his trunk. This may be a world first case of producing shoulder motion through FES.

Adult↗
PubMed1999

Electromyographic study relating to shoulder motion: control of shoulder joint by functional electrical stimulation.

The purpose of this study is to create the standard stimulation patterns of shoulder motion from electromyographic (EMG) data in 13 healthy human volunteers in order to control the movement of the paralyzed shoulder in quadriplegic and hemiplegic patients by functional electrical stimulation (FES). Simultaneous EMG measurement was made at 24 points of 17 major muscles relating to shoulder motion. Since the number of the output channels in the portable FES apparatus is limited, 12 major muscles were selected from statistically processing these EMG data and stimulation patterns were created based on the EMG data of these muscles. Thus three standard stimulation patterns were created to move the shoulder, i.e., (i) 90 degrees flexion to 90 degrees horizontal abduction, (ii) 90 degrees flexion to 20 degrees horizontal adduction, and (iii) 90 degrees abduction to 90 degrees horizontal adduction. With the created stimulation patterns, the restoration of the shoulder motion in plegic patients was successful and it will be reported in the next paper.

Adolescent↗
PubMed1999

[Helicobacter pylori infection and histological types of gastric cancer].

The relationship between Helicobacter pylori (H. pylori) infection and gastric cancer was evaluated clinicopathologically by histological types of gastric cancer (intestinal or diffuse type). Histological findings of resected stomach tissues and serum anti-H. pylori IgG antibody titers obtained in patients with early gastric cancer revealed H. pylori infection and associated inflammatory changes in all cases, irrespective of histological types of cancer, and suggested that diffuse type cancer occurs in the mucosa with marked inflammation at a relatively early stage of H. pylori infection, while intestinal type cancer occurs at a relatively late stage of infection in parallel with the progression of mucosal atrophy and intestinal metaplasia. Results of immunohistochemical staining showed high incidence of secretory components in and around cancer foci, suggesting that immunological mechanisms for H. pylori infection play a role in the development of gastric cancer regardless of its histological type.

Adenocarcinoma↗
PubMed1999

Production of secretory component and pathogenesis of gastric cancer in Helicobacter pylori-infected stomach.

The purpose of this study was to examine the production of secretory component (SC) and immunoglobulin A (IgA) in the gastric mucosa with Helicobacter pylori infection and to investigate the influence of immunological reactions on various phases of infection (gastritis, intestinal metaplasia, gastric cancer). Production of SC and IgA was assessed by immunohistochemical staining in (1) endoscopic biopsy samples of H. pylori-eradicated cases (n = 25), and (2) surgically resected stomach tissues of H. pylori-positive gastric cancer cases, intestinal type (IGC, n = 25) and diffuse type (DGC, n = 25). Before eradication therapy, all samples showed positive staining of SC and IgA in epithelial cells, and IgA was also positive in plasma cells in the mucosal layer. H. pylori bacteria were positively stained for SC and IgA. After treatment, the degree of SC and IgA staining in epithelial cells was reduced with successful eradication; but with intestinal metaplasia, SC staining was positive regardless of the results of treatment. In nonmetaplastic mucosa, SC-positive cells were increased in the glandular neck zone to the surface mucosal layer; and the intensity of SC staining was increased in proportion to the degree of mucosal inflammation and IgA-positive cell aggregation. In intestinal metaplasia, SC was positive irrespective of the degree of inflammation. Most cancer foci also showed positive staining of SC, irrespective of histological type. Production of SC and IgA was thought to be a specific reaction against H. pylori infection, occurring from the early to the late stages and not limited to intestinal metaplasia. It was suggested that immunological reactions against H. pylori infection might generally be involved with the pathogenesis of intestinal metaplasia and both histological types of gastric cancer (IGC and DGC).

Gastric Mucosa↗
PubMed1998

Prenatal identification of mos 45,X/46,X,+mar in a normal male baby by cytogenetic and molecular analysis.

We report a case of mos 45,X/46,X,+mar, diagnosed prenatally by amniocentesis, whose physical examination, including external and internal organs, along with serum testosterone values were normal five years after delivery. The mosaic karyotype was seen in 146 of 240 cells examined (amniotic fluid cells, 110/65; placental chorionic villi: 5/4; cord blood, 21/81; cultured skin fibroblasts, 10/90) from 386 metaphases, and the marker chromosome appeared as a small non-fluorescent acrocentric chromosome. All autosomes appeared normal, and no normal Y chromosome could be demonstrated. Analysis of 26 Y-chromosome loci by molecular techniques such as PCR, Southern analysis using multiple Y-specific DNA probes, and Hae III restriction endonuclease assessment of male-specific repeated DNA in the heterochromatic region of the Y chromosome, and fluorescence in situ hybridization (FISH), revealed the marker was derived from a Y chromosome including p terminal to q11.23, and paracentric inversion in the remaining Y long arm. The formation of testes can be considered as existence of SRY (sex-determining region of Y) as a testis-determining factor. The present report illustrates the importance of FISH and molecular techniques as a complement to cytogenetic methods for accurate identification and characterization of chromosome rearrangements in prenatal diagnosis.

Adult↗
PubMed1998

Rotational action of the supraspinatus muscle on the shoulder joint.

The shoulder joint allows three-dimensional movement. In order to analyze the function of the muscles which act on the shoulder joint, three-dimensional movements, including rotation, must be considered. Among muscles participating in the shoulder joint movement, the supraspinatus muscle is known to have abduction and stabilization effects on the shoulder joint. However, the rotational function of the supraspinatus muscle has not been identified, because few studies have been reported on it. This study investigates the rotating function of the supraspinatus muscle using electrical stimulation, magnetic resonance imaging (MRI) and anatomical examination. Electrical stimulation was applied selectively to the supraspinatus muscle of healthy subjects using percutaneous wire electrodes. The electrical stimulation was given at different positions of the shoulder joint. It was found that the electrically induced rotational movements changed their direction depending on the position of the shoulder joint. When the humerus was relatively in internal rotation, internal rotation resulted. When it was in external rotation, external rotation occurred. Regarding the abduction angle of the shoulder joint, external rotation was induced with an increase in the abduction angle, whereas internal rotation occurred when the abduction angle was decreased. By the dissection of cadavers and MRI examination, it was indicated that the relation between the running direction of the supraspinatus muscle and the center of rotation of the humeral head was dependent on the position of the shoulder joint. Those findings supported the results of electrical stimulation of the supraspinatus muscle at various shoulder positions. These results indicate that the bi-directional rotating function of the supraspinatus muscle is characterized by an anatomical relationship between the running direction of the supraspinatus muscle and the center of rotation of the humeral head.

Adult↗
PubMed1998

Analysis of voluntary finger movements during hand tasks by a motion analyzer.

Finger movements have primarily been classified by the final position of the hand and finger during deliberate hand activities, rather than as a description of the movement process. In addition, as of yet there have been no reports based upon objective data from the analysis of the motion of three finger joints during movement, and no reports exist that describe the relationship of the three joints' motion during these movements. This paper describes the relationship of the three finger joints during simple finger movements and hand tasks using measurements and analysis from a two-dimensional motion analyzer. Two prehensile movements were examined in 15 healthy volunteers: pure finger extension from finger flex position in different wrist positions (dorsi-flexion position, neutral position and palmar-flexion position of the wrist joint) and the grasping of discs of different diameter (10, 11, 12 and 13 cm). In the sequence of pure finger extension, where the grasping task was not requested, results showed that the movement was started from the proximal joint and extended to the distal joint of the finger, and full finger extension accomplished from distal to proximal, one after another, in any wrist position in most subjects. With the grasping of a disc, however, joint movement was initiated from distal to proximal and the final motion for grasping was carried to completion from the proximal to distal joints of the finger in most subjects. In addition, it was recognized that the proportion of the angular change in each of the three joints was different, as were the time duration of the joint motion and the pattern of the angular change. From these results, it is suggested that deliberate activities of the finger and sophisticated joint movements provided delicate adjustments to fit the fingers to the size of the object, as compared to the simple finger extension movement.

Adult↗
PubMed1998

Seminoma in a postmenopausal woman with a Y;15 translocation in peripheral blood lymphocytes and a t(Y;15)/45,X Turner mosaic pattern in skin fibroblasts.

We report an unusual case of a 55 year old Japanese woman with a seminoma but relatively normal menses. The patient was a phenotypic female with late onset menarche (18 years of age), who was amenorrhoeic for the first year, followed by menses of one to three days' slight flow with dysmenorrhoea, but an otherwise normal menstrual history. A typical seminoma was removed from the left adnexal region and an immature testis was identified separately as an associated right adnexal mass. Repeated karyotypic studies on peripheral blood lymphocyte cultures showed only 46,X,-Y,t(Y;15)(q12;p13). Cytogenetic examination of the patient's younger brother, who had fathered three healthy children, showed an identical karyotype. Mosaicism of 46,X,-Y,t(Y;15)(q12;p13)/45,X cell lines was found in skin samples from the patient's elbow and genital regions, although there were no clinical stigmata of Turner syndrome. An androgen receptor binding assay of cultured genital skin fibroblasts was negative. Molecular analysis using Southern blot hybridisation, PCR, and direct DNA sequencing showed that neither the patient nor her brother had a detectable deletion or other abnormalities of Y chromosome sequences, including the SRY (sex determining region of the Y chromosome) gene sequence. These findings suggest that Turner mosaicism of the 45,X cell line may have contributed to this atypical presentation in an XY female, although we cannot exclude abnormalities of other genes related to sex differentiation.

Blotting, Southern↗
PubMed1998

Application of functional electrical stimulation to the paralyzed extremities.

This paper describes restoration of motor function in patients with paralyzed extremities due to upper motor neuron disorders by functional electrical stimulation (FES). Percutaneously indwelling intramuscular electrodes were implanted into the muscles of the paralyzed upper and lower extremities to be controlled by FES. Stimulation patterns for extremity FES were created from electromyography (EMG) during motion in healthy subjects. By using a percutaneous FES system, all of the joint movement in the extremities could be controlled as long as severe lower motor neuron damage did not exist. In the paralyzed upper extremity, motor function of not only the hand but also the wrist, elbow, and shoulder could be restored with well-coordinated manner by EMG-based stimulation data and utilized for vocational tasks in the hemiplegic and quadriplegic patients. Continuous bias stimulation to the paralyzed muscle in combination with volitional contraction of its antagonistic muscles provided the patient with more volitional and natural control of the upper extremity. Restoration of locomotive movement in the paraplegics at around T-8 level was also achieved by FES under the usage of a walker.

Electric Stimulation Therapy↗
PubMed1998

Changes in messenger ribonucleic acid species in gerbil brain perturbation.

The differential display technique was applied to observe the molecular dynamism of messenger ribonucleic acid (mRNA) in this study. Using this technique, the changes in mRNAs in brain perturbation such as ischemia was observed to understand the molecular base of the reaction. The transient cerebral ischemia was induced by clipping both common carotid arteries for 5 minutes in Mongolian gerbils. The total RNA was extracted from the hippocampal tissue samples before ischemia, 6 hours and 2 days after ischemia. The mRNAs were reverse transcribed and subsequently amplified by polymerase chain reaction (PCR). PCR products were displayed by autoradiography as ladders on a denaturing polyacrylamide gel. According to the autoradiography, mRNAs were divided into three patterns: 1) mRNAs obtained from the control decreased at 6 hours after 5-minute ischemia and disappeared at 2 days completely; 2) decreased mRNAs at 6 hours after ischemia recovered at 2 days; and 3) new mRNAs appeared after cerebral ischemia. Located bands of interest on a gel were cut out and reamplification of complementary deoxyribonucleic acid was performed. The pGEM-T Vector System was used for subcloning of the amplified PCR products. The differential display technique is the powerful method for detecting genes that are unique to ischemic processes and reactions.

Animals↗
PubMed1998

[Anterior ischemic optic neuropathy in a case of polyarteritis nodosa].

A 68-year-old male admitted to our hospital because of fever, body weight loss and multiple mononeuropathy. He developed visual loss in his right eye due to anterior ischemic optic neuropathy (AION). Surgical treatment of jejunal perforation was performed and histological examination of jejunal ulcer confirmed the diagnosis of polyarteritis nodosa (PN). Combination therapy of steroid (prednisolone 50 mg/day) and cyclophosphamide (50 mg/day) was started, which saved him from any other ischemic change including that of his left eye. As long as we know, AION occurring in PN is very rare, that is, only 4 cases have been reported in Japan.

Aged↗
PubMed1998

[Intraoperative CT imaging system using a mobile CT scanner gantry mounted on floor-embedded rails for neurosurgery].

Many neurosurgeons prefer to use intraoperative computed tomographic (CT) scanning, when possible, to check whether there is residual lesion or unexpected bleeding. We report a practical intraoperative CT imaging system using a high-speed CT scanner installed in the operating room along with a digitally controlled neurosurgical operating table. We designed a rail-track system to mobilize the CT gantry. The gantry is fixed onto a motorized carrier that can be moved smoothly on a rail-track embedded in the floor and with a maximum reach of 2.85 m from the room's wall to the operating table. The longitudinal motion of the operating table is easily adjusted by a foot switch from manual control to automatic control directly from the CT scanner's computer like an ordinary CT scanner bed in increments of 2, 5 or 10 mm during CT scanning. Either a carbon-made radiolucent head frame or carbon-made head plate is used as a headrest. Using this CT scanner system, pre- and intraoperative CT scannings were performed on 46 patients with brain tumors, cervical lesions or other intracranial lesions. We could operate on the patient with enough working space between the mobile CT gantry and the operating table for microneurosurgery. We could obtain intraoperative CT imaging of a patient on the operating table while the surgical wound remained open, the surgical drapes kept in place, and the surgical position unchanged, saving time in intraoperative CT scanning and preparation for further surgery when needed. This intraoperative CT imaging system installed in the operating room should be useful for neurosurgery.

Brain↗
PubMed1998

[A case of malignant rheumatoid arthritis complicated by secondary amyloidosis and membranous nephropathy].

A 30-year-old man had been treated for malignant rheumatoid arthritis from 1989 with a non-steroidal anti-inflammatory drug, then bucillamine for six months and prednisolone. Mild proteinuria appeared in May 1994, 4 years after bucillamine therapy was conducted. The patient was admitted to our hospital for a renal biopsy in July 1994. The specimen revealed secondary amyloidosis and membranous nephropathy (MGN). These findings suggest that MGN unrelated to bucillamine therapy might have occurred with secondary amyloidosis in rheumatoid arthritis.

Adult↗
PubMed1997

The short-term effect of autogenous auricular cartilage graft following discectomy on the osteoarthrotic temporomandibular joint in sheep.

The aim of this experimental study was to determine the effect of auricular cartilage graft replacement on the progression of experimentally induced osteoarthrosis in sheep. Bilateral osteoarthrosis was induced in the sheep temporomandibular joint (TMJ). Three months later, discectomy and autogenous auricular cartilage grafting were performed unilaterally. At sacrifice, three months postrepair and six months postinduction of osteoarthrosis, it was found that the untreated side had extensive condylar osteoarthrosis and the grafted side showed evidence of fibrous repair. The graft prevented intra-articular adhesions and reduced degenerative changes, but there was a tendency towards graft perforation. Auricular cartilage grafting was effective in minimizing osteoarthrotic effects on the TMJ in the early stages after grafting.

Animals↗
PubMed1997

Current topics in clinical FES in Japan.

This paper reviews recent topics of clinical application of functional electrical stimulation (FES) for the paralyzed extremities in Japan. Transcutaneous and percutaneous FES systems have been clinically used in Japan. Candidates of extremity FES arer mostly stroke and spinal cord injury patients. By using percutaneous FES system, all of the joints of the upper extremity including the shoulder have been controlled for activities of daily living in the hemiplegic patient. Simultaneous FES control of the hand and wrist and the bilateral hands have also been achieved in C5 and C6 quadriplegics, respectively. Hybrid FES systems using percutaneous and surface electrodes, where FES is used in combination with orthoses, have been applied to the paraplegics because they are highly practical for assisting their locomotive activities. Percutaneous FES have been also provided the amyotropic lateral sclerosis patients with standing up motion. A total implant FES system with 16 output channels is currently developing as a next generation FES system.

Journal Article↗
PubMed1997

Short-term effect of fresh disk allograft on the osteoarthrotic sheep temporomandibular joint.

UNLABELLED: The aim of this experimental study is to evaluate the effect of fresh disk allograft on the osteoarthrotic temporomandibular joints in four sheep. STUDY DESIGN: Bilateral osteoarthrosis was induced in the sheep's temporomandibular joint. Three months later, unilateral diskectomy and fresh disk allograft repair were performed, with the contralateral joint being left as a control. At 6 months after the initial procedure, 3 months after the repair, the four sheep were sacrificed. RESULTS: It was found that the operated joint was fibrously repaired without ankylosis, whereas the control joint showed progressive disease. One grafted disk survived, but the other three were perforated and displaced. CONCLUSION: Fresh disk allograft does temper progression of the disease in the early stages.

Animals↗