This is the first report to document pit cells in the human liver. These cells were identified by characteristic electron-dense granules and rod-cored vesicles. The granules of human pit cells were smaller in number and size than those of the rat. In the present case of autoimmune hepatitis, pit cells and conventional agranular lymphocytes migrated into hepatic parenchyma and contacted degenerating and immature hepatocytes. Pit cells show natural killer activity (Kaneda et al., 1983), and may participate in development of lesions and cellular damage.

Autoimmune Diseases↗

PubMedDate not supplied

Mitochondrial derangement: possible initiator of microalbuminuria in NIDDM.

Morphometric analysis of 80 renal biopsy specimens from patients with non-insulin-dependent diabetes mellitus, who had been classified into four groups by grade of proteinuria and renal function, revealed mitochondrial enlargement in the proximal tubules, with cellular hypertrophy as an initial morphologic change in the microalbuminuria. This was followed by a thickening of the proximal tubular basement membrane and an increased interstitial volume, causing persistent overt proteinuria. Glomerular nodular and sclerotic lesions and severe tubulointerstitial damage became evident in the advanced stages. As an initial cause of microalbuminuria, the mitochondrial abnormality disturbed adenosine triphosphate (ATP) metabolism in proximal tubules, reducing active transport and causing urinary excretion of low-molecular-weight protein.

Albuminuria↗

PubMedDate not supplied

Accumulation of photosensitizer ATX-S10 (Na) in experimental corneal neovascularization.

PURPOSE: To determine the most appropriate time for laser irradiation to produce selective occlusion of new corneal vessels by photodynamic therapy (PDT) with a new photosensitizer, ATX-S10(Na). METHODS: The time course of the plasma levels of ATX-S10(Na) and the degree of dye accumulation in the corneal neovascularization after intravenous administration was determined in rabbit eyes. Plasma concentration of ATX-S10(Na) was analyzed by a spectrophotometer. The amount of ATX-S10(Na) in the new corneal vessels was measured by nitrogen-pulsed laser spectrofluorometry. Frozen sections of neovascularized cornea and iris were observed by fluorescence microscopy. RESULTS: Plasma ATX-S10(Na) concentration was highest 5 minutes after dye injection and rapidly decreased and reached almost zero at 24 hours, indicating its prompt excretion from the body. The amount of ATX-S10(Na) in the new corneal vessels as measured by nitrogen-pulsed laser spectrofluorometry increased and reached maximal level at 2 to 4 hours. Under fluorescence microscopy, the dye was more abundantly localized in the wall of new corneal vessels than in the normal tissue at 2 to 4 hours. CONCLUSION: These results indicate that laser irradiation between 2 and 4 hours after dye injection is appropriate for selective PDT with ATX-S10(Na) for the occlusion of new corneal vessels.

Animals↗

PubMedDate not supplied

Feasibility of using a magnetic tracking device for measuring carpal kinematics.

While several different methods have been used to measure carpal kinematics, biplanar radiography is generally considered to be the most accurate and popular one. However, biplanar radiography is tedious and so only pseudo-dynamic kinematics can be measured. Recently, magnetic tracking system has been developed for the measurement of joint kinematics which is versatile and easy to use and so the possibility of measuring motions dynamically. In this study, the capability of a magnetic tracking device to accurately measure carpal kinematics was investigated by comparing it with biplanar radiography. The kinematics of the third metacarpal, scaphoid, and lunate in five fresh cadaveric specimens were measured using both methods as the wrists were placed in eight positions. The finite screw rotation of each bone with respect to the distal radius during selecting the seven wrist motions was calculated for both measuring techniques and compared. In general, the kinematics for all three bones measured by using either magnetic tracking device or biplanar radiography was identical and showed no statistical difference. The averaged differences ranged from 0.0 to 2.0 degrees. These differences were due to the potential effect of the weight of the sensors and the interference of the attaching rod to the surrounding tissue. It is concluded that the application of the magnetic tracking device to carpal kinematics is warranted, if proper technical procedures as suggested are followed.

Aged↗

PubMedDate not supplied

Chimeric liver established by recipient type bone marrow cell transplantation to donor before to liver transplantation produces marked suppression of allograft rejection in rats.

Explore the source record for details and available documents.

Animals↗

PubMedDate not supplied

Postoperative subcoracoid impingement syndrome in patients with rotator cuff tear.

Impingement of the tendinous rotator cuff on the coracoid process (subcoracoid impingement syndrome) has rarely been reported as a cause of pain after surgery for rotator cuff tear. We evaluated clinical features, surgical results, and histopathology findings of resected coracoid processes in patients with subcoracoid impingement syndrome after anterior acromioplasty and management of rotator cuff tear. Pain at the anterior aspect of the shoulder, localized tenderness of the coracoid process, anterior shoulder pain on horizontal adduction testing, and positive subcoracoid block suggest subcoracoid impingement syndrome. Postoperative subcoracoid impingement syndrome was investigated in 11 of 216 cases with rotator cuff surgery. The average patient age at the time of surgery was 61.2 y (range, 28-78 y). Coracoplasty (partial resection of the posterolateral side of the coracoid process) was performed in 9 shoulders that had not responded to a 6-month regimen of conservative treatment. Complete pain relief was achieved in all cases. Histopathologic findings revealed hypertrophic changes of the fibrocartilage layer at the posterior aspect of the resected coracoid process. We concluded that subcoracoid impingement syndrome was an important factor in unsuccessful rotator cuff surgery and recommend that coracoplasty be performed on patients with symptoms of subcoracoid impingement syndrome after management of the rotator cuff tear.

Adult↗

PubMedDate not supplied

Outdoor winter activities of spinal cord-injured patients. With special reference to outdoor mobility.

Two hundred forty-seven patients with spinal cord injuries living in Hokkaido, the northern part of Japan, were mailed a questionnaire relating to winter outdoor activities. One hundred eight patients responded to the questionnaire, 98 males and 10 females, with ages ranging from 30 to 79 (mean, 53.3) yr. Injury levels of patients were: cervical in 23 patients, thoracic and thoracolumbar in 47, and lumbar in 38. All respondents were unable to walk independently because of quadriplegia or paraplegia. Approximately 90 percent of respondents found it necessary to go outside during the winter season. Eighty-five percent were outside during the coldest period. The most common reasons for outdoor activities were shopping and routine doctor's appointments. The main method of ambulating outside was a manual and/or electrically operated wheelchair, sometimes in conjunction with an automobile. However, there were many problems reported in using wheelchairs; for example, wheels and casters were very slippery on the snow and ice, casters were easily buried in the snow, and wheelchair rims were very cold to handle. It was also pointed out that exposure to cold weather induced physical problems such as muscle spasticity, pain, and numbness of lower extremities. This survey revealed that spinal cord-injured patients would benefit from a wheelchair specifically designed for winter conditions.

Accidental Falls↗

PubMedDate not supplied

Postnatal histogenesis of the cartilage plate of the spinal column: electron microscopic observations.

The cartilage plate in the vertebral columns in mice, from birth to 45 weeks of age, were examined by light and electron microscopy. At the day of birth, the intermediate part of the vertebral body consisted of bone, and its cranial and caudal parts were composed of thick cartilage. The cartilage was divided into an outer and an inner zone, according to the shape and arrangement of chondrocytes. In the deep portion of the outer zone, calcification developed from one week, and ossification appeared at eight weeks of age. The matrix in the superficial layer of the outer zone remained metachromatic during the development of the vertebral body. The inner zone of the cartilage showed columnar arrangements of chondrocytes and a metachromatic matrix like cartilaginous growth plates in long bones. Thus, vertebral bodies show development similar to that of long bones. The findings suggest that histogenetically the cartilage plate belongs to the vertebral body but not to the intervertebral disc and that age-related changes in the cartilage plate are concerned with age-related degenerative changes of the nucleus pulposus.

Animals↗

PubMedDate not supplied

Burst fractures with neurologic deficits of the thoracolumbar-lumbar spine. Results of anterior decompression and stabilization with anterior instrumentation.

Twenty-seven burst fractures with neurologic deficits of the thoracolumbar-lumbar spine were treated with an one-stage anterior operation consisting of anterior decompression through vertebrectomy, realignment and stabilization with Zielke instrumentation (12 patients), and our new anterior instrumentation (15 patients). Only two disc spaces directly related to the injury were fused. No patient showed neurologic deterioration after surgery. All 26 patients with incomplete lesions improved postoperatively, with 19 of them entering the next Frankel subgroup. The newly designed anterior instrumentation afforded enough stability to enable early ambulation with alignment and solid fusion.

Adult↗

PubMedDate not supplied

The effect of nonphysiologically high initial tension on the mechanical properties of in situ frozen anterior cruciate ligament in a canine model.

An experimental study was performed in 32 adult beagle dogs to clarify the effect of nonphysiologically high initial tension on the mechanical and histologic properties of in situ frozen anterior cruciate ligaments. Both anterior cruciate ligaments in each dog underwent the in situ freeze-thaw treatment. The tibial insertion of the ligament was then made free from the tibia along with a cylindrical bone block. In the right knee, an initial tension of 20 N was applied on the anterior cruciate ligament by translocating the bone block in the distal direction. In the left knee, this bone block was anatomically reduced. Each bone block was firmly fixed with an interference screw. Ten animals were sacrificed at 6 weeks and 10 at 12 weeks. The tensile strength and the tangent modulus in the highly tensioned knee were significantly less than those in the physiologically tensioned knee at 12 weeks. Histologically, cell nuclei appeared to be spindle-shaped in the physiologically tensioned knee, while oval nuclei and focal degenerative changes with a number of vacuoles were occasionally found in the matrix in the highly tensioned knee. This study demonstrated that a nonphysiologically high tension significantly deteriorates the mechanical properties of the in situ frozen anterior cruciate ligament compared with physiologic tension.

Animals↗

PubMedDate not supplied

An experimental evaluation of isometric placement for extraarticular reconstructions of the anterior cruciate ligament.

We measured the changes in distance between the tibial and femoral attachment points of the extraarticular ACL substitute during knee motion. To measure the changes in distance continuously and directly, a computer-assisted experimental system was developed using an electrolyte-in-rubber transducer. We used 6 cadaveric knees to measure changes in distance of 15 combinations during a simple flexion and extension knee motion. The distance became longer with flexion in each pair of attachment locations. Although the smallest change in distance was obtained between the posterolateral site of the femoral distal metaphysis and a point posterior to the Gerdy tubercle (percent average of the maximum strain was about 12%), it was concluded that the extraarticular ACL reconstruction is not recommended from a standpoint of isometry of the substitute.

Aged↗

PubMedDate not supplied

Biomechanical analysis of rehabilitation in the standing position.

Biomechanical analysis of the two-dimensional models composed from roentgenographic pictures and electromyographic analysis of the shear force exerted on the tibia during standing on both legs were conducted in 21 young adult males. The simultaneous contraction of the quadriceps and hamstrings was observed in all electromyograms. Amplitude observed on electromyograms of the hamstrings increased as the trunk flexion angle increased. The calculated average values of shear force were negative at every knee flexion angle (negative value means posteriorly directed force). As the trunk flexion angle increased, posterior drawer force increased at knee flexion angles of 30 degrees and 60 degrees. The simultaneous contraction of the quadriceps and the hamstrings was considered to be the main factor that influenced these results. Standing on both legs with knee and trunk flexion was considered to be applicable in the early stages after anterior cruciate ligament reconstruction.

Adult↗

PubMedDate not supplied

Quantitative evaluation of knee instability and muscle strength after anterior cruciate ligament reconstruction using patellar and quadriceps tendon.

Anterior cruciate ligament reconstruction using an autologous graft harvested from the central one-third of the patellar and quadriceps tendon was performed in 65 knees of 65 patients who were followed from 3 to 7 years. Mean anterior laxity of both knees was measured before and after surgery in each patient using the Styker Knee Laxity Tester. At 30 degrees of knee flexion, 58 patients (89%) had differences of less than 2.5 mm between the operated and unoperated knees. Quadriceps strength was measured with the Cybex II and was less than 50% of the uninjured knee at 3 months after surgery. In men, quadriceps strength returned to 78% of normal at 1 year and 85% at final followup. These values were equal to the preoperative level. In women, the quadriceps strength at final followup was 70%, significantly lower than preoperative strength. Hamstring strength recovered to equal the normal strength. Although anterior cruciate ligament reconstruction using one-third of the patellar and quadriceps tendon achieves stability, postoperative quadriceps weakness is a disadvantage. This weakness may be caused by impairment of the knee extensor mechanism resulting from harvesting the graft. We do not currently recommend this technique for anterior cruciate ligament reconstruction.

Adolescent↗

PubMedDate not supplied

Deterioration of mechanical properties of the autograft in controlled stress-shielded augmentation procedures. An experimental study with rabbit patellar tendon.

Effects of partial and complete stress shielding on mechanical properties and histology of in situ frozen patellar tendons were studied in 120 mature female Japanese White rabbits that were divided into three groups: completely stress-shielded, partially stress-shielded, and sham-operated groups. In the former two groups, tendon tension was reduced to 0% and about 30% of normal force, respectively, with a polyester artificial ligament. Tensile tests were conducted on patella-patellar tendon-tibia complexes harvested 1, 2, 3, 6, or 12 weeks after surgery. Tensile strength significantly decreased compared with the sham group to 17% and 28% at 3 and 6 weeks, respectively, in the completely stress-shielded group, and to 54% and 63% at 3 and 12 weeks, respectively, in the partially stress-shielded group. Patellar tendon cross-sectional area significantly increased to 156% and 157% at 2 and 3 weeks, respectively, in the completely stress-shielded group and to 133% at 2 weeks in the partially stress-shielded group, compared with the sham group. Stress shielding significantly changed tensile strength, tangent modulus, and cross-sectional area of in situ frozen patellar tendon; these changes depended on degree of stress shielding. Histologic observations indicated that remodeling occurred in the patellar tendon while there were no cells in the fascicle.

Animals↗