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Biomedical subjects

T Ikegami

Publications and source records attributed to T Ikegami.

At least 127 records · Page 7Linked to original sources
PubMed1996

A novel homozygous mutation of the myelin Po gene producing Dejerine-Sottas disease (hereditary motor and sensory neuropathy type III).

We have previously reported that heterozygosity for myelin Po gene mutations were associated with Charcot-Marie-Tooth disease type 1B (CMT1B) or Dejerine-Sottas disease. We investigated the Po gene in a family with clinical Dejerine-Sottas disease and found two children were homozygous for a deletion of Phe 64. The parents were heterozygous first cousins with subclinical CMT1B and slow nerve conduction velocities. These results suggest that the effect of homozygous Phe 64 deletion on impairment of myelination is dosage-dependent. Clinical phenotype and/or myelin impairment may be determined both by the type of mutation and by the dosage of mutated gene.

Base Sequence↗
PubMed1996

[A family of hereditary motor and sensory neuropathy type I with a mutation (Arg98-->His) in myelin Po--report on a second Japanese family].

A 46-year-old housewife had complaints of insidiously progressive muscle weakness and paresthesia in the distal lower limbs. On neurological examination, a slight to moderate degree of muscle weakness with slight atrophy was observed in the bilateral intrinsic hand muscles. A severe degree of muscle weakness with moderate atrophy was observed in tibialis anterior, gastrocnemius and soleus muscles. Muscle stretch reflexes were decreased in the upper limbs and absent in the lower limbs, without pathologic reflexes. She had a steppage gait. Vibratory sensation was slightly decreased in the hands and moderately decreased in the feet. Touch, pain and temperature sensations were also moderately decreased only in the feet. On laboratory examination, glycosuria (5.6g/dl) was noted. Fasting blood sugar was 226mg/dl with an elevated hemoglobin A1C level (12.7%). The right median motor and sensory nerve conduction velocities were 14.8 and 20.3 m/sec, respectively, with a markedly prolonged distal latency. No muscle action potential was obtained from stimulation of the right tibial nerve. Also, no nerve action potential was elicited from stimulation of the right sural nerve. A fascicular biopsy of the right sural nerve revealed the presence of both demyelinated and remyelinated axons, and an onion-bulb formation with a marked decrease in the density of the myelinated fibers. Based on the neurological examination and nerve conduction studies of the family members, a younger sister, younger brother and an elder daughter of the proband were found to be affected by demyelinating polyneuropathy. Diabetes mellitus was not found among the family members with laboratory evidences of demyelinating polyneuropathy. Based on the family history, an uncle on the mother's side of the proband, the proband's grandmother and a younger daughter of a proband's brother were considered to be affected. The uncle and grandmother had diabetes mellitus. Therefore, we concluded that this family had HMSN type I with autosomal dominant inheritance. In the studies on fluorescence in situ hybridization, and restriction fragment length polymorphism of the genomic DNA of the proband, a DNA duplication in the 17p11.2-12 region was not observed. However, the direct sequencing analysis of DNA fragments from genomic DNA encoding the Po gene of the proband revealed a substitution of histidine for arginine at the codon 98 in the extramembranous domain of Po. She was heterozygous for the mutant allele and normal allele. Alterations in the tertiary structure of the extramembranous domain of Po may result in an impairment of the peripheral myelin compaction. This is the second Japanese family with the same mutation (Arg98-->His) of myelin Po as reported previously by us, and this type of case is rare in the literature. Therefore, the mutation at the codon 98 may play a critical role in the development of the myelin abnormality in HMSN type IB.

Arginine↗
PubMed1996

Severe acute hepatitis A associated with acute pure red cell aplasia.

A rare case of severe acute hepatitis A complicated by pure red cell aplasia (PRCA) is reported. A 60-year-old man with jaundice and hepatomegaly was diagnosed as having acute hepatitis A by positive IgM anti-hepatitis A antibody (anti-HAV). Severe anemia rapidly developed 3 weeks after admission, and the patient was diagnosed with PRCA by both bone marrow smears and erythrocyte survival study. The anemia was transient and bone marrow recovered within 1 week. However, concomitant with bone marrow recovery, the hepatitis worsened. He became drowsy and disoriented and severe jaundice, ascites, prolonged prothrombin time, increased transaminase levels, and abnormal electroencephalogram (EEG) were exhibited. Plasma exchange transfusion and glucagon-insulin (GI) therapy improved the consciousness level, but bilirubin, transaminase levels, and IgM anti-HAV titer remained high. Intravenous administration of lipophilized prostaglandin E1 (lipo-PGE1) was added to the GI therapy. Bilirubin and transaminase levels were normalized in the 8th week after the initiation of this combination therapy (17 weeks after admission). The combined use of lipo-PGE1 with plasma exchange and GI therapy appeared to be useful for the prolonged severe hepatitis in this patient.

Acute Disease↗
PubMed1996

Emergence of net-grammar in communicating agents.

Evolution of symbolic language and grammar is studied in a network model. Language is expressed by words, i.e. strings of symbols, which are generated by agents with their own symbolic grammar system. Agents communicate with each other by deriving and accepting words via rewriting rule set. They are ranked according to their communicative effectiveness: an agent which can derive less frequent and less acceptable words and accept words in less computational time will have higher scores. They can evolve by mutational processes, which change rewriting rules in their symbolic grammars. Complexity and diversity of words increase in the course of time. The emergence of modules and loop structure enhances the evolution. On the other hand, ensemble structure lead to a net-grammar, restricting individual grammars and their evolution.

Algorithms↗
PubMed1996

Extended lateral segmentectomy using intraoperative ultrasound to obtain a partial liver graft.

The important features of extended lateral segmentectomy to obtain a partial liver graft comprising the left lateral segment and the left half of the medial segment are described with special reference to anatomical variation of the hepatic venous system. Ramification patterns of the hepatic vein tributaries around the juncture of the major hepatic veins with the inferior vena cava are delineated before starting liver resection, using intraoperative ultrasound. The left medial vein draining the left part of the medial segment is recognized close to the confluence of the middle and left hepatic veins. This tributary flows into the left hepatic vein in the majority of cases, but sometimes into the middle hepatic vein. The liver transection line is established in order to obtain the graft, including the drainage area of the left medial vein. Intraoperative ultrasound is indispensable for identifying the left medial vein in extended lateral segmentectomy.

Adolescent↗
PubMed1996

Should all hepatic arterial branches be reconstructed in living-related liver transplantation?

BACKGROUND: Because graft arteries are smaller and shorter in living-related liver transplantation (LRLT) than in whole or reduced-size liver transplantation from cadavers, arterial reconstruction is thought to be one of the critical points for success. METHODS: Thirty LRLT patients were classified into two groups: those in whom all graft hepatic arteries were reconstructed (group A), and those whom only had some were reconstructed (group B). In group A 17 patients had a single hepatic artery and three had two hepatic arteries. In group B the thickest one of several arteries was reconstructed, but the others were ligated after pulsatile back-bleeding from their cut stumps had been confirmed. The clinical results were compared between the two groups. RESULTS: Neither arterial thrombosis nor liver dysfunction related to the arterial blood supply was observed during the postoperative course. One case of bile leakage and two cases of bile duct stenosis occurred in group A. No significant difference was noted in the postoperative values of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase between the two groups. Overall patient and graft survival was 90%. CONCLUSIONS: Although several hepatic arteries may supply the potential allograft in LRLT, it is not always necessary to reconstruct all of them.

Adolescent↗
PubMed1996

Isolation and sequence determination of cDNA encoding mouse rab 4 and candidate approach for the beige mutation in mice.

The Chediak-Higashi syndrome is characterized by partial albinism and recurrent infections with giant granules in granulocytes. This syndrome has been proposed to have a defect in vesicular transport. Rab 4 is a member of a family of Ras-related small GTP-binding proteins, which has been mapped in the locus of the Chediak-Higashi syndrome. We isolated a full length cDNA of rab 4 from a cDNA library of mouse liver. The clone is 1428 base pairs (bp) in length and contains a 639 bp open reading frame encoding a polypeptide of 213 residues. The deduced amino acid sequence is highly homologous to rab 4 from rat and human. We analyzed rab 4 as a candidate gene of the beige mouse, but we could not find any change in the sequence of the coding region of rab 4 mRNA.

Amino Acid Sequence↗
PubMed1996

[Resolution of psoriasis vulgaris following allogeneic bone marrow transplantation for aplastic anemia].

A 36 year-old man had suffered from psoriasis vulgaris for about 25 years. He had received corticosteroids ointment and PUVA therapy with partial response. In 1987, he was diagnosed as having aplastic anemia (AA) and treated with various medications, but failed to respond. He received an allogeneic bone marrow transplantation (BMT) from his histocompatible sister in 1993. Conditioning regimen of BMT consisted of total lymphoid irradiation (7.5 Gy) and cyclophosphamide (200 mg/kg). Cyclosporin A and methotrexate were given for prophylaxis of graft-versus-host disease. On day 24, bone marrow examination disclosed normocellular marrow and karyotypic analysis completely confirmed the donor's origin. Before BMT, he had systemic psoriatic plaques with scales, together with nail involvement. After BMT, psoriatic plaques disappeared and nail deformity improved. He has remained in remission of his AA and completely free of psoriasis in the absence of immunosuppressive or other treatments. The cause of psoriasis is thought to be an immune-mediated disorder. Our case supports the observation that changing the host's immune system through allogeneic BMT can achieve remission of psoriasis. It is suggested that allogeneic BMT may be one strategy for the treatment of intractable immune-mediated disorders.

Adult↗
PubMed1996

[The combination therapy with vinca-alkaloid slow infusion and cholchicine was effective to refractory idiopathic thrombocytopenic purpura. The patient could receive femoral head replacement in safety].

A 46-year-old man with idiopathic thrombocytopenic purpura (ITP) refractory to corticosteroid, splenectomy and other drugs was admitted to our hospital in August, 1994, because of aseptic necrosis of the right femoral head. Although high-dose intravenous gamma-globulin was ineffective, the platelet count was increased within two weeks by the combination therapy that consisted of 0.02 mg/kg vincristine alternating with 0.1 mg/kg vinblastine by slow infusion at a 1-week interval, and oral 1.5 mg/day colchicine. He subsequently underwent the femoral head replacement. This combination therapy seems to be useful for refractory ITP in preparation for surgery.

Colchicine↗
PubMed1996

Improvement of Tsukiji free fish market in Tokyo ("Kaizen" of work environment).

"TSUKIJI" is one of the biggest and most famous Free Fish Markets in the world, but there are many problems on the working condition because it was built about 60 years ago. Our investigation was held 1991 to 1993 to give some improvements regarding layout of buildings, working time, heat condition at refrigerator, working posture, and so on. We used a questionnaire on daily life and health care of workers, time study with measurement of heartbeats, and checklist (using Checklist for Improvement of Safety-Health and Working Conditions,' made by ILO). The main occupations in TSUKIJI were seller, buyer, delivery worker, and refrigerator maintenance worker. Their starting time was early in the morning, usually between 2:00 a.m. and 5:00 a.m., but the hardest one was delivery workers starting at 9:00 p.m. They used auto cargo car for carrying to shops from refrigerator or from auction places many times. Sellers had two different types of work. First, the seller set up the auction, numbering the fish (or cases of seafood), arranging them in order, and so on. The rest of the work was transaction of invoices, sometimes using VDU with almost sitting. These works did not look well balanced. Buyer of tuna cut if like lumber by electric saws did not have guard for protection and there were more than 200 machines. Overlooking the market by checklist, some problems were clarified, and suggestions for improvement include restructuring the whole layout of the market or reforming buildings, standardization of the cases, adjustment of health facilities, safety protection on tools and machines, management of working system, working posture, health care, and so on.

Adult↗
PubMed1995

Prevention of hepatic artery thrombosis in pediatric liver transplantation.

Hepatic artery thrombosis after orthotopic liver transplantation is a serious complication, especially in children. We report our experience with intensive anticoagulant therapy during and after living-related liver transplantation in pediatric recipients. Twenty-four patients between 5 months and 15 years of age were studied. The mean diameter of the anastomosed hepatic arteries was 2.7 mm. The anticoagulant therapy consisted of low-molecular-weight heparin, antithrombin III concentrates, prostaglandin E1, fresh frozen plasma, and a protease inhibitor. The profiles of the coagulation and fibrinolytic systems were monitored by measuring several parameters, including plasma levels of thrombin-antithrombin III complex, antithrombin III, plasmin-alpha 2 plasmin inhibitor complex, fibrin degradation product D-dimer, tissue type-plasminogen activator, and plasminogen activator inhibitor-1. Acceleration of the coagulation system and delayed recovery of the fibrinolytic system were observed during the early postoperative days. The plasma level of antithrombin III activity was maintained within the normal range by the administration of antithrombin III concentrates. None of the recipients developed hepatic artery thrombosis. Children have been reported to be at a greater risk of developing hepatic artery thrombosis than adults due to the small diameters of their hepatic arteries and the postoperative hypercoagulable state. We believe that the intensive anticoagulation therapy described in this study, the main concept of which is the early correction of imbalance between the coagulant and anticoagulant systems, could become a model for the prevention of hepatic artery thrombosis in pediatric liver transplantation patients.

Adolescent↗
PubMed1995

Clinical significance of the trimethadione tolerance test in chronic hepatitis: a useful indicator of hepatic drug metabolizing capacity.

Trimethadione (TMO) was chosen as an indicator of quantitative hepatic microsomal function, and its pharmacokinetics were studied in 52 patients with chronic hepatitis. Findings in these patients were compared with those for 26 healthy subjects and 13 patients with renal failure. Patients with chronic hepatitis, but not those with renal failure, showed significant reduction in clearance (CL) and prolongation of half-life (t1/2), and the extent of abnormalities was found to reflect the severity of histologic changes in liver tissue. The serum dimethadione (DMO)/TMO ratio 4 h after the administration of TMO altered in parallel with the CL and t1/2 of TMO, and abnormalities in this simple ratio were also related to the histologic severity of changes in the liver tissue. A low DMO/TMO ratio (< 0.4) was associated with advanced histologic changes (chronic active hepatitis with bridging or chronic active hepatitis with cirrhosis), whereas a high DMO/TMO ratio (> 0.4) was associated with mild histologic changes (chronic persistent hepatitis or chronic active hepatitis) (sensitivity, 0.81; specificity, 0.86). These results indicate that the DMO/TMO ratio, which can be obtained from a single blood sampling, reflects the histologic severity of changes in tissue liver, and that the TMO tolerance test is a useful indicator of quantitative liver function.

Chronic Disease↗
PubMed1995

Venous tumor thrombosis and cavernous transformation of the portal vein in a patient with gastric carcinoma.

A case of extensive extra- and intrahepatic portal tumor thrombosis, with no metastatic foci in liver parenchyma, secondary to advanced gastric carcinoma in a 69-year-old man is reported. The portal tumor thrombosis was characterized by enlargement of the thrombosed segment of the vein, decreased density mass without intraluminal enhancement of the involved vein, nonvisualization of the portal venous branch in the involved lobe, and the so-called cavernous transformation of the portal vein. The surgically resected gastric specimen showed Borrmann type 3 advanced papillary adenocarcinoma. The portal tumor thrombus is presumed to have arisen from vascular invasion in the primary foci of gastric carcinoma, and then to have permeated the portal vein without invasion of liver parenchyma.

Adenocarcinoma, Papillary↗
PubMed1995

Randomized control trial of lipo-prostaglandin E1 in patients with acute liver injury induced by lipiodol-targeted chemotherapy.

OBJECTIVE: The aim of this study was to prove whether lipo-prostaglandin E1 (PGE1)/glucagon insulin therapy combination could prevent the acute liver dysfunction induced by Lipiodol (iodized oil)-targeted chemotherapy for hepatocellular carcinoma. METHODS: This study was a randomized control trial. Patients in two groups (groups A and B: n = 29) were each given an intravenous injection of 10 units of insulin and 1 mg glucagon every 12 hours for 1 week after Lipiodol-targeted chemotherapy. Patients in group B (n = 11) were each given an intravenous injection of 20 micrograms lipo-PGE1 every 12 hours over 1 week. Several items, including conventional liver function tests, were evaluated at the start of the study and on the days 1, 2, 4, 7, and 14 after Lipiodol-targeted chemotherapy. RESULTS: Combined lipo-PGE1/glucagon-insulin therapy can prevent the elevation of serum ALT level and total bilirubin level after Lipiodol-targeted chemotherapy. In the group A (glucagon-insulin therapy only), the maximum level in the follow-up interval was statistically higher than that in the pretreatment level (p < 0.05), whereas there was no significant difference in group B (treated with combined glucagon-insulin therapy and lipo-PGE1). Changes of ALT level in group B tend to be lower than in group A; however, there was no significant statistical difference. There were few episodes of side effects in both groups. CONCLUSION: Combined lipo-PGE1/glucagon-insulin therapy may be a safe and effective treatment for the prevention of acute hepatic failure.

Aged↗