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H Komori

Publications and source records attributed to H Komori.

At least 55 records · Page 3Linked to original sources
PubMed1998

Power Doppler imaging of hepatic tumours: differential diagnosis between hepatocellular carcinoma and metastatic adenocarcinoma.

We evaluated the usefulness of power Doppler imaging in the differential diagnosis between hepatocellular carcinoma and metastatic adenocarcinoma. Forty-seven patients with hepatocellular carcinoma and 18 patients with metastatic adenocarcinoma were evaluated using power Doppler imaging. The colour signals of hepatic tumours were graded as follows: 1, colour signals only in the marginal area; 2, small dot or dotted line colour signals within the tumours; 3, continuous solid line colour signals within the tumours. The grade 3 colour signals were classified in the following three patterns; winding line pattern, stretched line pattern and mixed pattern. The colour signals of hepatocellular carcinoma were grade 1 in seven patients, grade 2 in 11 and grade 3 in 29. The colour signals of metastatic adenocarcinoma were grade 1 in three patients and grade 3 in 15. Of the 29 hepatocellular carcinoma patients with a grade 3 signal, 26 patients had winding line patterns and three had mixed patterns. Of the 15 metastatic adenocarcinoma patients with a grade 3 signal, 12 patients had stretched line patterns and three had mixed patterns. In conclusion, power Doppler imaging is useful in the differential diagnosis between hepatocellular carcinoma and metastatic adenocarcinoma to evaluate the colour signal pattern within the tumour.

Adenocarcinoma↗
PubMed1997

Evaluation of motor function during thoracic and thoracolumbar spinal surgery based on motor-evoked potentials using train spinal stimulation.

STUDY DESIGN: Using compound muscle action potentials after train spinal stimulation, intraoperative motor functional monitoring was performed during thoracic and thoracolumbar spinal surgery. OBJECTIVES: This study was designed to clarify the clinical usefulness of train spinal stimulation and to determine the critical point of compound muscle action potential change at which neurologic injury during surgery occurs. SUMMARY OF BACKGROUND DATA: In 1995 the authors reported that train spinal stimulation allows for the recording of compound muscle action potentials, even in animals and humans under general anesthesia. The facilitative effect of train stimulation overcomes the suppressive effects of anesthetics and allows potentials to pass through synapses, thereby enabling a reliable recording of lower extremity compound muscle action potential. METHODS: Multisegmental recording of compound muscle action potentials after train spinal stimulation was conducted on 34 patients Undergoing surgical treatment for thoracic or thoracolumbar lesions. During surgery, train stimuli (5 pulse, Interstimular Interval: 1 ms) were administered using an epidural electrode introduced transcutaneously. Compound muscle action potentials were recorded from a total of 128 muscles. Anesthesia was maintained using fentanyl and propofol or nitrous oxide with or without isoflurane. Muscle relaxation was attained mainly by controlled infusion of vecuronium bromide. The percent occurrence of recordable compound muscle action potentials was determined, and the potential changes were correlated with changes in muscle strength. RESULTS: Compound muscle action potentials could be recorded from at least one muscle in 94% of the patients, even in most patients with severe motor dysfunction. The compound muscle action potential changes before and after surgical maneuver were divided into four grades. All compound muscle action potential changes in deteriorated muscles belonged to Grade 2 (a 10% latency delay) or Grade 3 (disappearance). CONCLUSIONS: The success rate in obtaining muscle potentials was greatly enhanced when all of the following methods were used: train spinal stimulation, anesthetic with weak suppressive effect, multiple muscle recording, and percutaneous introduction of epidural electrode. The critical point of compound muscle action potential change should be defined as a 10% latency delay or disappearance. Multisegmental muscle potential after train spinal stimulation is the most appropriate method for thoracic and thoracolumbar spinal surgery.

Adult↗
PubMed1997

Chemonucleolysis with human stromelysin-1.

STUDY DESIGN: Immunohistologic analysis was performed on surgically removed samples of herniated nucleus pulposus to examine the expression of stromelysin-1. We performed in vitro and in vivo experiments to determine whether recombinant human (rh) stromelysin-1 is capable of degrading nucleus pulposus. OBJECTIVE: To analyze the production of stromelysin-1 in various types of herniated nucleus pulposus, and to examine the effects of this recombinant protein on nucleus pulposus tissues. SUMMARY OF BACKGROUND DATA: The authors previously demonstrated a progressive decrease in herniated nucleus pulposus size in some of the transligamentous and sequestration types of herniated nucleus pulposus using magnetic resonance imaging. An increased production of stromelysin-1, a cartilage proteoglycan degrading enzyme, in herniated nucleus pulposus was reported recently. The authors speculated that if stromelysin-1 is involved in the degradation of herniated nucleus pulposus, stromelysin-1 itself may be used as a chemonucleolytic agent. METHODS: Immunohistologic analysis using streptoavidin-biotin method was performed on 20 herniated nucleus pulposus samples to investigate the expression of stromelysin-1. Five herniated nucleus pulposus samples were incubated in a tissue culture medium in the presence or absence of rh stromelysin-1. After 24 hours of incubation, their weight changes were measured, and the loss of proteoglycan was assessed by Safranin O staining. Rat nucleus pulposus tissues were obtained from coccygeal intervertebral discs, and autologous subcutaneous transplantation was performed. Rh stromelysin-1 was injected into the grafted materials, and the reduction in size was followed by two-dimensional measurements from the skin surface, using engineer's calipers. RESULTS: Immunohistologic analysis demonstrated the production of stromelysin-1 in the granulation tissues of herniated nucleus pulposus. When stromelysin-1 was injected into the murine nucleus pulposus tissues, they reduced in size more rapidly than the control group. In addition, human herniated nucleus pulposus materials obtained at surgery showed significant weight loss when treated with stromelysin-1 in an organ culture system. Safranin O staining revealed extensive depletion of proteoglycan in these herniated nucleus pulposus samples. CONCLUSIONS: Stromelysin-1 is a possible key enzyme in herniated nucleus pulposus resorption, and stromelysin-1 may be a good candidate for use in chemonucleolysis. Administration of human stromelysin-1 may physiologically facilitate the resorption process of herniated nucleus pulposus, increase the healing rate and decrease complications after chemonucleolysis.

Adult↗
PubMed1997

Sequential dynamics of monocyte chemotactic protein-1 expression in herniated nucleus pulposus resorption.

We previously demonstrated that the granulation tissues of herniated nucleus pulposus are composed of a marked infiltration of macrophages that strongly express monocyte chemotactic protein-1. Monocyte chemotactic protein-1 is a chemotactic cytokine that contributes to the activation and recruitment of macrophages. Relatively little is known about its role in the resorption process of herniated nucleus pulposus. To clarify the sequential dynamics of expression of monocyte chemotactic protein-1 in the granulation tissues of herniated nucleus pulposus, we introduced a rat autologous transplantation model of nuclear materials onto its lumbar dura mater and performed immunohistological analysis and competitive polymerase chain reaction assay using the grafted samples. Immunohistological analysis demonstrated that the majority of infiltrating mononuclear cells expressed monocyte chemotactic protein-1. Monocyte chemotactic protein-1 mRNA was expressed in the first 3 weeks after the procedure and was significantly and maximally upregulated at 1 week. To determine whether human recombinant monocyte chemotactic protein-1 facilitates the resorption process of herniated nucleus pulposus, we introduced another model of autologous transplantation, wherein the nuclear materials were grafted to the abdominal subcutaneous tissues and recombinant monocyte chemotactic protein-1 was subsequently applied to these materials. When monocyte chemotactic protein-1 was injected into the murine nucleus pulposus tissues, they reduced in size more rapidly than in the control group. These findings suggest that monocyte chemotactic protein-1 plays an important role in the recruitment of macrophages in the early phase of the resorption process of herniated nucleus pulposus and that its application may physiologically facilitate the resorption process of the nucleus pulposus.

Animals↗
PubMed1997

Changes in plasma glucose, insulin, glucagon, catecholamine, and glycogen contents in tissues during development of alloxan diabetes mellitus in rats.

Alloxan monohydrate (ALX) was given to rats (20 mg/100 g body weight) and plasma glucose (PG), immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and catecholamine (CA) as well as the glycogen (G) content in the liver, muscle, and kidneys were measured. Although whether hypoglycemia was present immediately after injection was not clear, the PG level increased, with a modest peak after 2 h. The PG levels in rats receiving food 6 h after ALX injection increased substantially after 1 h and continued to increase after 24 h. Although the IRI level increased slightly 10 min after the injection, low amounts were present for up to 24 h due to continued fasting. There was a rise in the IRG level at 10 min after injection, and then it decreased again slowly to a low level during fasting. No change was observed in the CA level. Hepatic G further decreased at 30 min after ALX injection and started to increase from 2 h to a peak level after 18 h. Almost no changes were noted in muscle tissues. The G content in the renal cortex remained almost unchanged, although it tended to decrease slightly after 8 h. When rats were fed 6 h after ALX injection, the IRI level rose slightly. Hepatic G at 6 h after feeding was nearly equal to that during feeding itself, but it then decreased rapidly. Muscular G became equal to that during feeding. Renal G showed a clear tendency to increase 6 h after feeding and became about four times that during periods when rats were fed ad lib. In conclusion, not only PG, IRI, and IRG, but also tissue G levels were shown to change markedly in the early stage of ALX induced diabetes.

Alloxan↗
PubMed1997

CSF beta-endorphin levels in patients with infantile autism.

We measured CSF levels of beta-endorphin, an opioid hormone, in 19 patients with infantile autism and in 3 patients with Rett syndrome, and compared them with control values. In infantile autism, CSF levels of beta-endorphin did not differ significantly from those of age-matched controls. There was no significant correlation between CSF levels and clinical symptoms, including self-injurious behavior, pain insensitivity, and stereotyped movement. However, CSF levels of beta-endorphin were significantly higher in the patients with Rett syndrome than in the control (p < .05). Data suggest that neurons containing beta-endorphin may not be involved in patients with infantile autism. Thus, there is no relationship between dysfunction of brain opioid and autism.

Autistic Disorder↗
PubMed1997

Objective evaluation of pain in various spinal diseases: neuropeptide immunoreactivity in the cerebrospinal fluid.

A quantitative analysis was performed of substance P-like immunoreactivity (SPLI) and of beta-endorphin-like immunoreactivity (beta-ENDLI), in the cerebrospinal fluid (CSF) in various diseases. The results reported to date have not been consistent. The purpose of this study was to investigate whether or not the concentration of SPLI or that of beta-ENDLI in CSF demonstrated any potential for assessing the degree of subjective pain in various spinal diseases. SPLI in CSF was measured by radioimmunoassay in 158 patients with a spinal disease; involving 57 patients with a lumbar disc herniation (LDH), 38 with lumbar canal stenosis (LCS), 46 with cervical myelopathy (CM) and 17 with cervical radiculopathy (CR), and also in 20 healthy controls. beta-ENDLI in CSF was measured in 25 of these same patients; involving 12 with LDH, seven with LCS and six with CM, and also five of the same controls. The concentration of serum SPLI was also measured in 50 of these 158. The severity of pain was self-evaluated by each patient using a linear visual analogue scale (VAS). Their Japanese Orthopaedic Association (JOA) score was also calculated objectively using the clinical findings. Correlations were investigated among the concentrations of SPLI and beta-ENDLI in the CSF and the VAS and JOA clinical assessments of these patients. The concentration of SPLI in CSF was significantly higher in various spinal diseases than in control (P < 0.05), and was correlated with the severity on the VAS and with the JOA score. However, beta-ENDLI was not correlated with either the VAS or the JOA score. We conclude that the measurement of the SPLI concentration in CSF has the potential for assessing objectively the severity of pain associated with various spinal diseases.

Activities of Daily Living↗
PubMed1996

Upregulated expression of chemokines in herniated nucleus pulposus resorption.

STUDY DESIGN: Immunohistologic examination was performed on surgically removed samples of herniated nucleus pulposus. OBJECTIVES: To determine what cell types predominate in the granulation tissues of herniated nucleus pulposus, and to elucidate whether chemokines are involved in the resorption process of herniated nucleus pulposus. SUMMARY OF BACKGROUND DATA. The study population consisted of 30 patients suffering from herniated nucleus pulposus. Five macroscopically normal discs were obtained from spinal cord tumor and spinal cord injury managed with anterior discectomy (age range, 27-63 years) as a healthy control group. METHODS: Immunohistochemical analysis was used to analyze the expression of chemokines. RESULTS: A marked infiltration of macrophage and vascular proliferation was identified with a T lymphocyte infiltration of mild degree in the granulation tissues. This tendency was more prominent in the exposed group compared with the nonexposed group. Infiltrating macrophages, fibroblasts, and endothelial cells in the granulation tissues strongly expressed monocyte chemotactic protein-1 and macrophage inflammatory protein-1 alpha. Statistical analysis demonstrated that the exposed group was more abundant in Factor VIII, monocyte chemotactic protein-1, and macrophage inflammatory protein-1 alpha positive cells than the unexposed group. CONCLUSIONS: Inflammatory cells and their positivity for chemokines, such as monocyte chemotactic protein-1 and macrophage inflammatory protein-1 alpha, are associated with blood vessels. Chemokines, such as monocyte chemotactic protein-1 and macrophage inflammatory protein-1 alpha, were overexpressed in macrophages, fibroblasts, and endothelial cells, suggesting that these chemokines contribute to activation and recruitment of macrophages in a paracrine or autocrine fashion.

Adolescent↗
PubMed1996

Predominant p53 mutations in enzootic bovine leukemic cell lines.

The role of the p53 tumor suppressor gene in bovine lymphosarcomas, a fragment of about 100 bp corresponding to approximately 97% of the open reading frame of the p53 gene was first amplified from single-strand cDNA originated from calf thymus by polymerase chain reaction PCR) and sequenced to obtain the bovine wild-type p53 gene. At the amino acid level, the omologies of the bovine p53 gene with the human, mouse, chicken and cat p53 genes were 0.9%, 72.8%, 52.7% and 82.3%, respectively. Moreover, eight bovine leukemic cells lines were studied for alterations in the p53 gene. These lines showed no significant somatic alterations in southern blot analysis, and expressed 2.5 kb p53-specific transcripts in Northern blot analysis. In mutation analysis using the reverse transcriptase-PCR technique, we detected three missense point mutations in four of these bovine leukemic cell lines. These mutations occurred in the 'hotspots' of the p53 gene. Thus p53 mutations predominantly occur in BLV-transformed cell lines and seem to be necessary for development of enzootic bovine leukosis (EBL).

Amino Acid Sequence↗
PubMed1996

Homeostasis of cell-surface glycosphingolipid content in B16 melanoma cells. Evidence revealed by an endoglycoceramidase.

This paper describes the homeostasis of glycosphingolipid (GSL) on the cell surface as revealed for the first time by an application of endoglycoceramidase (EGCase) capable of hydrolyzing the linkage between the oligosaccharide and the ceramide of various GSLs. When cell-surface GSLs of B16 melanoma cells were hydrolyzed by the action of EGCase, the synthesis of GSLs was found to increase transiently, possibly due to activation of UDP-glucose:ceramide glucosyltransferase. As a result, the cell-surface GSL content was restored quickly to exactly the same level found without the EGCase treatment, if EGCase was removed from the cell culture. Treatment of erythrocytes with EGCase caused the suppression of de novo ceramide production, resulting in maintenance of the ceramide content of B16 cells at the same level even after EGCase treatment. The signal for homeostatic regulation could be the ceramide release found to mimic in part the action of EGCase; it suppressed de novo production of ceramide and was directly converted to GSL, NeuAc alpha 2,3GAl beta 1,4Glc beta 1,1 N-acetylsphingosine (C2-ceramide GM3). Our finding demonstrates a novel form homeostatic regulation coupled to the GSL-synthesizing system in mammalian cells for maintaining the contents of both cell-surface GSLs and free ceramide. Since many opportunistic pathogens were found to produce EGCase extracellularly, this restoration mechanism could also be present as a defense mechanism against microbial EGCase.

Animals↗
PubMed1996

The natural history of herniated nucleus pulposus with radiculopathy.

STUDY DESIGN: The present study retrospectively investigated the morphologic changes that occurred during conservative treatment of patients with unilateral leg pain resulting from herniated nucleus pulposus without significant lumbar canal stenosis. OBJECTIVES: The results were correlated with clinical outcomes and extruding forms to determine which type of herniated nucleus pulposus had the greatest capacity for spontaneous regression and how rapidly such regression might occur. SUMMARY OF BACKGROUND DATA: The study population consisted of 77 patients with radiculopathy. METHODS: All patients complained primarily of unilateral leg pain, and 94% had positive tension signs. Additionally, 32% exhibited muscle weakness corresponding to the symptomatic nerve root. All patients were studied more than twice using magnetic resonance imaging during conservative therapy at a mean interval of 150 days. Morphologic changes on magnetic resonance imaging fell into four categories, with herniated nucleus pulposus classified into three types using T1-weighted sagittal views. Each patient was reexamined on the same scanner; 53 patients were examined twice, and 24 patients were examined more than three times. RESULTS: Morphologic changes, with the exception of 13 false-negative cases, basically corresponded to clinical outcome. In half of the cases that showed some improvement at follow-up evaluation, improvement of clinical findings were seen before those observed on magnetic resonance imaging. Migrating herniated nucleus pulposus frequently presented an obvious decrease in size, and even disappearance in seven cases. The further the herniated nucleus pulposus migrated, the more decrease in size could be observed. The cases apparently corresponding to "protrusion" showed little or no change on follow-up magnetic resonance imaging. Regarding the mechanism of herniated nucleus pulposus disappearance, exposure to the vascular supply undoubtedly took a part, although many factors were suspected to have some influence. CONCLUSION: Morphologic changes on magnetic resonance imaging mainly corresponded to clinical outcomes but tended to lag behind improvement of leg pain. Disappearance of herniate nucleus pulposus was seen frequently in the cases of migrating disc herniation, and it was presumed that exposure to the vascular supply had a lot to do with this phenomenon.

Adolescent↗
PubMed1996

Monitoring of anterior cervical spinal cord function.

Anterior surgery is frequently chosen for treatment of cervical myelopathy. However, intraoperative spinal cord recording has rarely been used to monitor the function of the ventral columns. We report a method of monitoring evoked spinal cord potentials useful for detection of minor injury of the anterior spinal cord. Evoked spinal cord potentials elicited in cats by thoracic spinal cord and labyrinth stimulation were studied. Evoked intraspinal field potentials recorded after labyrinth stimulation were confirmed to originate from the vestibulospinal tract in the ventral columns. Low-amplitude potentials were recorded from the posterior epidural space. However, this method has not been used clinically because of difficulty in obtaining selective stimulation in humans. Spinal cord potentials evoked by thoracic stimulation were recorded from the anterior and posterior epidural spaces. The amplitude of the potentials was large enough to permit quantitation of neural function. We confirmed that anterior recording was more sensitive in detecting ventral column injury than posterior recording was. Based on these findings, we used anterior recording from the disc clinically for anterior spinal cord monitoring during anterior cervical surgery.

Acoustic Stimulation↗
PubMed1996

Endoscopic variceal ligation versus endoscopic injection sclerotherapy: comparison of hepatic and renal function.

OBJECTIVES: The aim of the present study was to compare the safety of endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy (EIS) in terms of liver and kidney functions in patients with liver cirrhosis. METHODS: Forty-four patients admitted to Takatsuki General Hospital between February 1991 and March 1993 with esophageal varices due to liver cirrhosis were randomly assigned to receive either EVL or EIS. Serum levels of AST, ALT, total bilirubin (T-bil), direct bilirubin (D-bil), prothrombin time (PT), hepaplastin test (HPT), antithrombin III (ATIII), creatinine (Cr), and blood urea nitrogen (BUN) were measured before and 24 h, 3 days, 7 days, and 14 days after both forms of therapy. RESULTS: Significant elevations of serum T-bil, serum D-bil, and serum ALT and AST levels were observed in the EIS group but not in the EVL group. No significant increases of serum PT, HPT, ATIII, BUN, or Cr levels were observed after treatment in either group. CONCLUSION: EVL should be considered a first choice therapy for eradicating esophageal varices.

Endoscopy↗
PubMed1995

Spinal cord monitoring of the ventral funiculus function. Analysis of spinal field potentials after galvanic vestibular stimulation.

STUDY DESIGN: This study was designed to examine the possibility of a new spinal cord monitoring method using galvanic vestibular stimulation to monitor the function of the ventral funiculus of the spinal cord. OBJECTIVES: To settle the problems of previous monitoring methods by using galvanic vestibular nerve stimulation, which is highly selective for monitoring the function of the ventral funiculus of the spinal cord. SUMMARY OF BACKGROUND DATA: Although various spinal cord monitoring methods have been used, there are still problems because potentials recorded by these methods do not reflect selectively the function of the ventral funiculus of the spinal cord, which is vulnerable during anterior spinal surgeries. METHODS: In anesthetized cats, field potentials evoked by galvanic stimulation of the labyrinth were recorded from the epidural space of the spinal cord. The origin of these potentials was determined by mapping field potentials from within the upper cervical spinal cord using a micropipette and by examining the effect of sectioning the brainstem on the evoked potentials. RESULTS: The spinal cord potentials evoked by galvanic stimulation between the bilateral labyrinths could be recorded from the epidural space, and these potentials mainly originated from the ventral and ventromedial funiculus of the spinal cord. The latency and intraspinal distribution of the evoked potentials and the effect of sectioning the medial longitudinal fascicle on the evoked potentials indicated that the earliest component of the evoked potentials reflects mainly the activity of the vestibulospinal tract. CONCLUSIONS: Recording spinal cord potentials evoked by galvanic vestibular stimulation from the epidural space appears to be a potential technique to monitor the functional state of the ventral funiculus during anterior spinal surgeries.

Animals↗
PubMed1995

Conversion of short-chain ceramides to short-chain ceramide GM3 in B16 melanoma cells.

We report that short-chain ceramide (Cer), C2- and C6-Cer, were immediately glycosylated and finally converted to short-chain Cer GM3 in B16 melanoma cells. By addition of either C2- or C6-Cer to a cell culture of B16 melanoma in the presence of [14C]Gal, the radiolabeled precursor, was incorporated into each of two novel glycosphingolipids (GSLs) within 30 min along with synthesis of normal GSLs. These novel GSLs were identified as C2-, C6-Cer cerebrosides and C2-, C6-Cer GM3, respectively. In comparison with C2-Cer, C6-Cer was found to be much more efficiently converted to the GSLs, whereas no glycosylated sphingosine was detectable when it was added in place of short-chain Cer.

Ceramides↗
PubMed1995

A new method of multisegment motor pathway monitoring using muscle potentials after train spinal stimulation.

STUDY DESIGN: Evoked muscle and nerve action potentials after spinal stimulation for intraoperative monitoring were investigated using a modified stimulation technique. Animal experiments and clinical application were performed. OBJECTIVES: To contrive a useful method of intraoperative motor pathway monitoring under inhalation anesthesia. SUMMARY OF BACKGROUND DATA: Many different kinds of procedures have been reported. No reliable method that reflects pure motor tract function has been established. METHODS: Characteristic of our stimulating technique was the use of numbered consecutive pulses ("train stimulation"). In 16 cats, optimum condition of train stimulation, effects of anesthetic agents, and conductive pathway were examined. In 35 patients, muscle potentials evoked by train stimulation were recorded, and clinical usefulness was evaluated. RESULTS: In the experimental study, the optimum stimulus condition was determined 1 ms interstimulous interval train of five pulses. Conductive pathway of this method was identified as a lateral column by selective spinal cord transection. In the clinical application, by using train stimulation, multisegmental muscle potentials were obtainable even using inhalation anesthetics. CONCLUSIONS: The facilitative effects of train stimulation, attributed to temporal summation, are considered to overcome the suppression of inhalation anesthesia. The evoked muscle potentials by train spinal stimulation reflect the functions of pure motor tract and is the only, extremely efficient method for intraoperative motor pathway monitoring.

Action Potentials↗