Biomedical subjects
Publications and source records attributed to Y Kariya.
We present a case of recurrent saddle embolism 6 days and 9 days following corrective osteotomy of the left femur in a 64-year-old man with a history of atrial fibrillation. Although saddle embolism is a relatively rare event, orthopaedic surgeons should be aware of this condition.
During various knee operations, the changes caused by the surgical invasion to the infrapatellar fat pad (IPF) is still unknown. If any changes exist, it will have great influence especially on growing generations. Eighty-four Japanese white rabbits (6-month-old) were divided into three groups: the resection group involving resection of the IPF, the graft group involving resection and reimplantation of the IPF, and the no-surgery group. All these surgical procedures were done in right knees. In all left knees, only arthrotomy was performed, serving as the sham side. After 3, 6, 12, and 24 weeks of the operation, the rabbits were killed. Lengths of the patellar tendon and patellar were measured in lateral X-ray. In order to eliminate individual differences in the patellar height, we defined a new index as percent patellar height (PPH) which indicated the percentage of the patellar height of surgery side compared with that of the sham side. The PPH was 90.6% (3 weeks), 83.0% (6 weeks), 73.6% (12 weeks), and 74.7% (24 weeks) in the resection group, while it was 88.4% (6 weeks), and 88.9% (24 weeks) in the graft group. Postsurgical scar tissue formation occurring where the IPF was removed prevented the normal growth of the patellar tendon. Reimplantation of the IPF lessened the adhesion of the patellar tendon to the surrounding tissue, and better growth of the tendon. These results showed that preservation of the IPF in young individuals could be crucial for the normal growth of the patellar tendon, and critical as well for the prevention of the degeneration of the articular surface.
Treatment once extension contracture of the knee has completed is difficult and costly. The most effective treatment might be the prevention of contracture, especially after joint injury. In order to establish an effective method for contracture prevention we first made an extension contracture in rabbit knees, then studied the effect of a sheet made from hyaluronic acid and carboxymethyl cellulose (HA/CMC) for the prevention of knee contracture. One hundred and twenty two mature male Japanese white rabbits were divided into three groups: (1) group B (n=42), where bony holes were made at the medial and lateral epicondyles, (2) group H (n=40), where HA/CMC sheets were placed on the bony holes, and (3) group S (n=40),where only arthrotomy was performed. All surgical procedures were performed on the right knees. All right knees were fixed at 45 degrees using external fixators; this is the maximum extension angle the rabbit is able to tolerate and still walk. At 1, 3, and 6 weeks after surgery, we measured the moment necessary to flex the knee using a special device. We defined the moment as flexion moment (FM). Forty four left knees were also tested as group N, not operated on and serving as the healthy side. In all groups, FM was increased parallel to the increment of flexion angle from 45 degrees to 115 degrees . At many flexion angles, the FM in group B was higher than those of group S at 3 and 6 weeks. The FM in group H was significantly lower than those of group B at 85 degrees and 95 degrees of flexion at 6 weeks after the operation. By macroscopic observation, the area and degree of adhesion were greater in group B than those of group S. In group H, adhesions around the bony hole were less evident than in group B at 6 weeks after the operation. By histological examination, dense granulation tissue was found adjacent to the bony hole in group B at 3 and 6 weeks after the operation. In contrast, in group H the amount of granulation tissue was smaller at 3 and 6 weeks after the operation than those of group B. The usage of HA/CMC sheet should be effective for prevention of contracture occurring after trauma such as treatment for intra-articular fracture.
AIM: The present study attempted to use HE staining to clarify morphological changes in muscle fibres during recovery from disuse muscle atrophy. METHODS: Disuse muscle atrophy was induced by suspending 7-week-old male Wistar rats by their tails for 5 weeks (hindlimb unloading or HU group). Histological changes in the soleus muscle (SOL) during the recovery process were examined and compared with those in control rats who were raised freely without unloading (C group). RESULTS: Wet muscle mass and muscle cross-sectional area per fibre of SOL in the HU group were 52 +/- 5 and 22 +/- 5% of those in the C group, respectively. Muscle atrophy was largely attributable to decreases in the size of muscle fibres, rather than to muscle fibre damage or loss. Muscle mass in the HU group increased quickly after reloading, but recovery of cross-sectional area per fibre was slow, with mean area in the HU group measuring 69 +/- 10% of that in the C group even after 5 weeks of reloading. After 1, 2 and 5 weeks of reloading, incidences of muscle fibres displaying central nuclei (regenerated muscle fibres) were 7.4 +/- 2.4, 7.2 +/- 6.3 and 19.2 +/- 14.5%, respectively. CONCLUSION: These findings suggest that recovery of muscle fibres atrophied by disuse involves not only growth of atrophied muscle fibres, but also regeneration of muscle fibres. Cross-sectional areas recovery of atrophied muscle fibres thus continues after increases of muscle mass.
PURPOSE: This study aimed to compare the effects of computer-assisted, text-based and computer-and-text learning conditions on the performances of 3 groups of medical students in the pre-clinical years of their programme, taking into account their academic achievement to date. A fourth group of students served as a control (no-study) group. METHOD: Participants were recruited from the pre-clinical years of the training programmes in 2 medical schools in Japan, Jichi Medical School near Tokyo and Kochi Medical School near Osaka. Participants were randomly assigned to 4 learning conditions and tested before and after the study on their knowledge of and skill in performing an abdominal examination, in a multiple-choice test and an objective structured clinical examination (OSCE), respectively. Information about performance in the programme was collected from school records and students were classified as average, good or excellent. Student and faculty evaluations of their experience in the study were explored by means of a short evaluation survey. RESULTS: Compared to the control group, all 3 study groups exhibited significant gains in performance on knowledge and performance measures. For the knowledge measure, the gains of the computer-assisted and computer-assisted plus text-based learning groups were significantly greater than the gains of the text-based learning group. The performances of the 3 groups did not differ on the OSCE measure. Analyses of gains by performance level revealed that high achieving students' learning was independent of study method. Lower achieving students performed better after using computer-based learning methods. CONCLUSION: The results suggest that computer-assisted learning methods will be of greater help to students who do not find the traditional methods effective. Explorations of the factors behind this are a matter for future research.
We studied carpal tunnel pressure and outcome of endoscopic carpal tunnel release in 42 patients (53 hands) with carpal tunnel syndrome (CTS) and receiving long-term hemodialysis. We compared these results with those of 41 patients (49 hands) with idiopathic CTS. Pressure was measured peroperatively: first, before dilation of the carpal tunnel; second, after dilation but before release of the transverse carpal ligament; and third, after completion of the release. In patients receiving long-term hemodialysis, the highest pressures were 76.9, 56.0, and 7.8 mmHg respectively. In patients with idiopathic CTS, pressures were 68.8, 44.1, and 4.0 mmHg respectively. The clinical outcome was inferior in patients receiving long-term hemodialysis.
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Chondroitin sulfate E (CSE) markedly enhanced plasminogen activation by tissue plasminogen activators (t-PAs) and urinary plasminogen activator (u-PA) in vitro; in the presence of 10 microg/ml of CSE, the potentiation factors of single chain of t-PA, two chain of t-PA and u-PA were 400, 140 and 130, respectively. Though the potentiation activity of CSE gradually decreased when it was depolymerized by chondroitinase ABC, the specific disaccharide from CSE still showed significant activity. Glycosaminoglycan (GAG) from sea cucumber, which possesses a very similar core structure to CSE, but has additional sulfated fucose branches exhibit very weak activity. These results suggested that the minimal structural requirement in CSE to enhance plasminogen activation by plasminogen activators is GlcUAbeta1-3GalNAc(4S,6S) and that additional branching sugars abolish the activity.
Although regioselective removal of 6-O-sulfate groups of heparin has been undertaken by several researchers, complete 6-O-desulfation with little side reaction has not been attained successfully. In this work, a modified method with a certain silylating reagent, N-methyl-N-(trimethylsilyl)trifluoroacetamide, has been established to produce completely 6-O-desulfated heparin with few other chemical changes. The degrees of 6-O-desulfation were estimated by means of chemical disaccharide analyses and/or (13)C NMR spectra. Although the completely 6-O-desulfated heparin lost about 20% of 2-O-sulfate groups, any other chemical changes and depolymerization were not detected. The completely 6-O-desulfated heparin displayed strong inhibition of COS-1 cell adhesion to basic fibroblast growth factor (bFGF)-coated well in a dose-dependent manner, as was clarified by the competitive cell-adhesion assay. Furthermore, the completely 6-O-desulfated heparin was shown to promote in vitro A31 fibroblast proliferation in a dose-dependent manner in the presence of bFGF. These results suggest that signal transduction through bFGF/bFGF receptor in A31 cells occurs in the absence of 6-O-sulfate groups in heparin. The involvement of 6-O-sulfate group(s) of heparin/heparan sulfate in the promotion of bFGF mitogenic activity was reported by several groups. This discrepancy between our results and those of other groups would be due to the differences in molecular size of heparin/heparan sulfate derivatives and/or cell species used for the assay.
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STUDY DESIGN: A 5-year prospective study. OBJECTIVES: To investigate trunk muscle weakness as a risk factor for low back pain in asymptomatic volunteers. SUMMARY OF BACKGROUND DATA: Muscle strength has not been sufficiently studied as a risk factor for low back pain. METHODS: The study participants included 30 male and 37 female volunteers (mean age, 17 +/- 2 years), who neither reported nor had ever been treated for low back pain. Trunk muscle strength was measured isokinetically (60 degrees/sec), using the trunk extension and flexion and torso rotation units. The peak torques of the volunteers' extension, flexion, rightward rotation, and leftward rotation were measured, and the agonist/antagonist ratios were calculated as extension/flexion and left rotation/right rotation ratio. The volunteers then were followed prospectively for 5 years to determine the incidence of low back pain and were classified into a non-low back pain group (volunteers with no low back pain during the 5-year follow-up period) and a low back pain group (volunteers who experienced low back pain during this period). RESULTS: The low back pain group consisted of 8 male and 10 female volunteers. There were no significant differences between the non-low back pain group and the low back pain group regarding age, height, weight, the peak torque values, or the left rotation/right rotation ratio. However, the extension/flexion ratio of the low back pain group (men, 0.96 +/- 0.27; women, 0.77 +/- 0.19) demonstrated significantly lower values than that of the non-low back pain group (1.23 +/- 0.28 and 1.00 +/- 0.16 for men and women, respectively, P < 0.05). CONCLUSIONS: An imbalance in trunk muscle strength, i.e., lower extensor muscle strength than flexor muscle strength, might be one risk factor for low back pain.
Proteins with affinity to heparin under physiological conditions were isolated from bovine cerebral cortex. First, the extract of cerebral cortex was applied to a chondroitin polysulfate column under physiological conditions. Then, the pass-through fraction was applied to a heparin column. Among the bands on SDS polyacrylamide gel electrophoresis of the fraction bound to the heparin column, the major one was identified as fructose 1,6-bisphosphate aldolase (FPA), a cytosolic enzyme involved in the glycolytic pathway. The results indicated that FPA is a heparin-binding protein which exhibits no affinity to chondroitin polysulfate. The results of affinity chromatographies revealed that FPA binds to intact heparin and modified heparins desulfated at C2 OH of the iduronic acid residue or at C6 OH or C2 NH2 of the glucosamine residue. When 6-O-desulfated heparin was employed as the affinity ligand, a single peak having FPA activity was isolated from the extract of bovine cerebral cortex. By further Mono Q chromatography and Superdex gel-filtration, five isoenzymes were purified with more than 50% recovery. These isoenzymes were identified as FPA A4, A3C1, A2C2, A1C3, and C4 by native electrophoresis with and without 4 M urea and subsequent amino acid sequence analysis. The use of 6-O-desulfated heparin affinity chromatography thus facilitated the purification of FPA.
An examination of the effects of artificial stress induced by adrenocorticotropin (ACTH) on total and differential leukocyte counts, plasma cortisol levels, metabolic profiles and peripheral blood polymorphonuclear leukocyte (PMN) function was performed on Japanese Black steers kept in a cold environment, with the following regimes; 1) -5 degrees C x ACTH (100 IU/day for 3 days), 2) 0 degrees C x ACTH, 3) 15 degrees C x ACTH and 4) 15 degrees C x PBS. Blood samples were collected before and at 1, 2, 24, 48, 72 and 96 hr prior to the application of the stressor. The plasma cortisol level was found to greatly increase at one hr after the first treatment of ACTH, particularly so in animals exposed to -5 degrees C. Total leukocytes (-5 degrees C and 0 degrees C experiments, respectively), the monocytes (-5 degrees C), neutrophils and eosinophils (-5 degrees C, 0 degrees C and 15 degrees C, respectively) obviously increased just after the first administration, although lymphocyte counts at -5 degrees C were inversely related to those described above. All of these tendencies were augmented by the cold environment except for eosinophils. The chemiluminescent (CL) response of PMN decreased in the ACTH-administered steers at an early stage of post-administration, however, it tended to recover from the lower-than-base value in the cold-affected steers. ACTH administration resulted in higher plasma glucose (Glu) compared to a control, although only steers housed at -5 degrees C evidently showed lower plasma inorganic phosphorus (IP). No abnormal serum acute phase protein, or immunosuppressor, was noted. ACTH thus appears not only to promote physiological reactions but also to temporarily suppress PMN cellular immune function in Japanese Black steers. Although, a cold environment rapidly restored the CL activity to over the pre-administrational value, suggesting that a vital response was activated by crymo-stimuli.
A 26-year-old man presented with a 38 degrees C fever of undetermined origin in November 1977. His fever subsided in 1 month, but recurred concomitantly with dysphagia on December 10. For this reason, the patient visited our out patient clinic on December 15, and was hospitalized because a mass was found radiographically in the left lower lung field. A contrast-enhanced computed tomographic scan of the chest revealed an irregularly-shaped mass encircling the esophagus. Based on open-lung biopsy findings, the mass was diagnosed as non-Hodgkin's lymphoma, diffuse pleomorphic type. Neither swelling of the superficial lymph nodes nor hepatosplenomegaly was detected, and a bone-marrow aspiration specimen disclosed no atypical cells. Ga scintigraphy found accumulation only in this region, suggesting the posterior mediastinum as the origin of the lymphoma. Reports of non-Hodgkin's primary lymphoma in the posterior mediastinum are rare. Further, to our knowledge, there have been no reports at all on the diffuse pleomorphic type to date. This case was accordingly considered to be of highly informative value.
Compositional analyses of heparin (Hep) and heparan sulfate (HS) have been undertaken with disaccharide units obtained by either enzymatic digestion with heparitinases or hydrazinolysis/deamination reaction of polysaccharides. Unsaturated disaccharide units generated by the enzymatic method are detectable on HPLC with a uv detector recording absorbance at 230 nm. On the other hand, disaccharide units generated by the chemical method possess a component of 2,5-anhydromannose (AnMan) bearing aldehyde groups in addition to intact iduronic acid (IdoA) or glucuronic acid (GlcA). The aldehyde groups of the disaccharide units are usually reduced with sodium borotritide, and detected by radiochromatography. Both of them, however, involve inevitable experimental problems, such as the use of costly enzymes and radioisotopes. In the present study, we have established a novel composition analysis system for Hep and HS essentially based on the chemical method. After hydrazinolysis/deamination treatment of Hep and HS, the aldehyde groups of AnMan in the disaccharide units generated were coupled with paranitrophenyl (PNP-) hydrazine instead of reduction with sodium borotritide, AnMan-CH=N-NH-PNP (AnMan-PNP) being formed. Then, the PNP-labeled disaccharides were pre-treated on a SepPak C-18 cartridge column, and subsequently separated and detected on ion-pairing reversed-phase HPLC with a detector recording absorbance at 390 nm. With the present system, the order of elution was GlcA-AnMan-PNP (GM), IdoA-AnMan-PNP (IM), IdoA(2S)-AnMan-PNP (ISM), IdoA-AnMan(6S)-PNP (IMS), and IdoA(2S)-AnMan(6S)-PNP (ISMS). As an application, the disaccharide compositions of heparin from bovine intestine and heparan sulfate from bovine kidney were analyzed by the present method, and the results were comparable to those obtained by a well-established enzymatic method. The present compositional analysis was demonstrated to be reliable and economical.
OBJECTIVE: To investigate whether the expression of B7-1 is involved in NK cell activation. METHODS: B7-1 gene was transfected into K562 cell line (a sensitive target cell of NK cell, without MHC class I expression) by electropolation. Specific cytotoxicity of NK cells to B7+K562 cell was assayed by 4-h Cr release assay. The proliferation of NK cells induced by B7+K562 cell was analysed by Flow Cytometry. Expansion of NK cells and cloning of NK cells were performed by mixed lymphocyte-tumor cultures and limiting dilution analysis. Production of TNF-A, GM-CSF and IFN-A was detected by ELISA tests. RESULTS: The cytotoxicity of NK cells to B7+K562 cell could be induced and that the number of NK cells could be increased by stimulation with B7+K562 cells, in particular, further enhanced with biotherapeutic agent such as OK432 and IL-2. Also, NK cell clones were established. Cytokines such as TNF- A, INF- A and GM-CSF were detected in the supernatant produced by NK cell clones. In addition, culture of lymphocytes in the presence of supernatant produced by NK cell clones and tumor antigens resulted in an increased autologous tumor killing(ATK). CONCLUSION: These findings suggest that K562 cells transfected by B7-1 gene may elicit a series of antitumor immunity and these cells may be used for further development of therapeutic tumor vaccine.
Fucose-branched chondroitin sulfate E was prepared from the body wall of sea cucumber Stichopus japonicus. The purified glycosaminoglycan (GAG) was chemically desulfated, followed by carboxyl reduction. Intact, desulfated, and desulfated/carboxyl-reduced GAG fractions were subjected to per-O-methylation. GC-MS analyses of the resultant partially methylated alditol acetates demonstrated that the fucose branch is formed by two fucopyranosyl residues linked glycosidically through position (1-->3), and that the fucose branch and glucuronic acid are almost equimolar. In addition, it was elucidated that about 20% of the branches stretch from O-3 position of a glucuronic acid moiety of the core chondroitin sulfate polymer, while remaining fucose branches are postulated to protrude from O-4 and/or O-6 position(s) of a N-acetylgalactosamine moiety. This fucose branch was also confirmed to be highly sulfated according to six kinds of substitution pattern in methylation analysis.
Complete drying of heparin with various concentrations of NaOH by lyophilization caused specific 2-O-desulfation to various degrees without detectable depolymerization or other chemical changes. In order to assess the importance of 2-O-sulfate groups in uronate residues to promote FGF-1 and FGF-2 activities, various 2-O-desulfated (2-O-DS-) heparins were quantitatively examined for their effects on FGF-1 and FGF-2-induced proliferation of BALB/c3T3 clone A31 (A31) cells and the chlorate-treated cells. Twenty-seven percent or less loss to the 2-O-sulfate groups had no effect on the ability to activate both FGF-1 and FGF-2, while 44% loss resulted in a significant loss of the ability. Complete loss of the ability was observed in 2-O-DS-heparins with 75% or more 2-O-desulfation. These results suggest that a high content of 2-O-sulfate groups in uronate residues of heparin is required for activation of both FGF-1 and FGF-2.