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Biomedical subjects

M Miyahara

Publications and source records attributed to M Miyahara.

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

A patient with a hemoglobin variant (Hb JLome) unexpectedly detected by HPLC for glycated hemoglobin (Hb A1c).

A rare hemoglobin variant, Hb JLome, was identified by chance in a male patient with diabetes mellitus (DM). The patient had no evidence of anemia or hemolysis. However, when his glycated hemoglobin (Hb A1c) was examined by high-performance liquid chromatography (HPLC) to assess the state of his DM, an abnormal Hb was unexpectedly detected on the chromatogram. The morphology of the red blood cells was normal. A fast-moving band as well as a normally moving Hb band, of roughly equal intensities, were observed by cellulose acetate membrane electrophoresis. The oxygen equilibrium curve was essentially normal (P50 = 3.59 kPa). In other words, the ability of the patient's Hb to carry oxygen was nearly the same as that of typical Hb A. The stability of his Hb in isopropanol was normal, and all the functions of his Hb that were tested were essentially normal. The identity of the abnormal Hb was finally determined, by sequencing the globin gene, to be Hb JLome, which is produced by a point mutation changing AAG to AAC at the 59th codon in exon 2 of the Hb beta chain. As previously reported, replacing the beta 59 lysine with asparagine does not affect the function of Hb or the red blood cells. There have been only five documented cases of Hb JLome in Japan. Interestingly, all these cases are from Kyushu Island. When an abnormal chromatogram for Hb A1c is unexpectedly obtained, it is worthwhile searching for an abnormal Hb, even if there are no signs that suggest its existence, such as anemia, hemolysis, erythrocytosis, or cyanosis.

Aged↗
PubMed1998

The relationship of strength and muscle balance to shoulder pain and impingement syndrome in elite quadriplegic wheelchair rugby players.

Wheelchair athletes are susceptible to injuries related to overuse of the shoulder, in particular shoulder impingement syndrome. The present study examined the relationship of shoulder pain to demographic details, isokinetic strength and muscle balance in 8 elite quadriplegic rugby players. Demographic data were collected using personal interviews and each subject was clinically examined for signs of impingement syndrome by a physician. In addition each subject underwent bilateral isokinetic strength testing of the shoulder at 60 and 180 deg/s for abduction/adduction and internal/external rotation. A series of step-wise multiple discriminant analysis successfully predicted clinical symptoms from demographic, muscular strength and balance data. In particular, there was a significant deficit in adductor strength and this was related to shoulder pain and wasting of the scapular muscles. This strength deficit may be due to the high level of spinal lesions in the quadriplegic population. The level of spinal lesion may contribute to the aetiology of shoulder pathology in quadriplegia, and differentiate it from that observed in able-bodied athletes who exhibit weak abductors.

Adult↗
PubMed1998

HLA class I and II alleles and susceptibility to generalized pustular psoriasis: significant associations with HLA-Cw1 and HLA-DQB1*0303.

HLA alleles in generalized pustular psoriasis (GPP) were investigated to clarify the etiology and/or pathogenesis of this disease. Not only serological typing of HLA class I and II antigens but also genotyping of HLA class II alleles were carried out in twenty-six unrelated Japanese patients with GPP. These patients were classified according to their history of psoriasis vulgaris (PV). Serological typing revealed a significantly high incidence of HLA-Cw1 (Pc = 0.04) in the patients as compared with Japanese healthy controls. The frequency of HLA-B46 was particularly high in the patients with GPP and a previous history of PV. Genotyping of HLA class II alleles showed a highly significant increase in HLA-DQB1*0303 (Pc = 0.01) in the patients vs. the healthy controls. In particular, HLA-DQB1*0303 was significantly more frequent in the patients with no prior history of PV than in those with a history of PV. Analysis on linkage disequilibrium showed remarkably different patterns for HLA class II haplotypes between the patients and the healthy controls. Based on the comparative analysis among the amino acid sequences of the beta 1-domain of the HLA-DQB1*03 alleles, proline at residue 55 was suggested to be important as a common amino acid for determination of the susceptibility to GPP. These results revealed not only an association between the etiology and/or pathogenesis of GPP and HLA, but also different mechanisms of the immune response between the patients with GPP and PV.

Amino Acid Sequence↗
PubMed1998

[Experience of coronary and great vessel angiography by transradial puncture].

The introduction of 5F and even 4F catheters allows transradial coronary arteriography and aortography. The efficacy and limitation of angiography via the radial artery using 5F catheter was prospectively evaluated in 200 consecutive patients. Cardiac catheterization with diagnostic angiography was successfully performed in 198 of 200 patients, including 11 patients with acetylcholine provocation test, 21 with bypass graft angiography, 38 with aortography and 5 with biopsy of the left ventricular myocardium. The transradial approach was not indicated in one patient without normal Allen's test and in one with weak radial pulse. In four patients, guide wire support was needed during manipulation because of marked tortuosity in the innominate artery. The sheath was removed immediately after the completion of the procedure, followed by 5 hours of tourniquet hemostasis without manual compression. The postoperative resting period was reduced. Peripheral vasospasm occurred in 2.5% of cases, but could be eliminated by administration of isosorbide dinitrate and lidocaine. Subcutaneous hemorrhage in the puncture site was observed in 3.0% of cases, but required no additional compression. Transradial catheterization is a minimally invasive, safe and practical alternative to the brachial or femoral artery approach in patients with normal Allen's test.

Aortography↗
PubMed1997

Interaction of PKN with alpha-actinin.

PKN is a fatty acid- and Rho-activated serine/threonine protein kinase, having a catalytic domain homologous to protein kinase C family. To identify components of the PKN-signaling pathway such as substrates and regulatory proteins of PKN, the yeast two-hybrid strategy was employed. Using the N-terminal region of PKN as a bait, cDNAs encoding actin cross-linking protein alpha-actinin, which lacked the N-terminal actin-binding domain, were isolated from human brain cDNA library. The responsible region for interaction between PKN and alpha-actinin was determined by in vitro binding analysis using the various truncated mutants of these proteins. The N-terminal region of PKN outside the RhoA-binding domain was sufficiently shown to associate with alpha-actinin. PKN bound to the third spectrin-like repeats of both skeletal and non-skeletal muscle type alpha-actinin. PKN also bound to the region containing EF-hand-like motifs of non-skeletal muscle type alpha-actinin in a Ca2+-sensitive manner and bound to that of skeletal muscle type alpha-actinin in a Ca2+-insensitive manner. alpha-Actinin was co-immunoprecipitated with PKN from the lysate of COS7 cells transfected with both expression constructs for PKN and alpha-actinin lacking the actin-binding domain. In vitro translated full-length alpha-actinin containing the actin-binding site hardly bound to PKN, but the addition of phosphatidylinositol 4, 5-bisphosphate, which is implicated in actin reorganization, stimulated the binding activity of the full-length alpha-actinin with PKN. We therefore propose that PKN is linked to the cytoskeletal network via a direct association between PKN and alpha-actinin.

Actinin↗
PubMed1997

Cytomegalovirus-associated myelodysplasia and thrombocytopenia in an immunocompetent adult.

Myelodysplasia and severe thrombocytopenia in association with cytomegalovirus (CMV) infection in immunocompetent adults have rarely been reported. We describe a previously healthy man who developed severe thrombocytopenia with myelodysplastic changes of bone marrow and multiple autoimmune abnormalities following CMV infection. We also discuss possible mechanisms leading to myelodysplasia and thrombocytopenia in CMV infection. We believe that CMV infection should be considered in the differential diagnosis of myelodysplasia and acute thrombocytopenia.

Adult↗
PubMed1997

Ocular manifestations in adult T-cell leukemia/lymphoma.

Ocular manifestations of adult T-cell leukemia/lymphoma (ATL) are rare events. However, several ocular lesions which resulted from human T-cell leukemia virus type I (HTLV-I) infection have been reported, including direct infiltration of ATL cells, cytomegalovirus retinitis, and HTLV-I-associated uveitis (HAU). The aim of this study was to characterize ocular involvement in ATL and to correlate these lesions with HTLV-I proviral DNA integration. Three patients with acute-type ATL and ocular lesions were evaluated hematologically and ophthalmologically. Analysis of HTLV-I proviral DNA was carried out with a standard Southern blot technique using DNA from abnormal lymphocytes in peripheral blood. Two patients developed intraocular lesions located within intermediate and/or posterior segments which were caused by infiltration of ATL cells. Ocular lesions in one patient, which were localized to the anterior-intermediate segment, closely resembled those of HAU. Analysis of HTLV-I proviral DNA revealed multiple integrations in all three patients. The present study indicated heterogeneity in ocular manifestations of ATL. Multiple HTLV-I proviral DNA integrations may be associated with intraocular involvement in this disease.

Adult↗
PubMed1997

Molecular genetic analysis of HLA class II alleles in Japanese patients with melanoma.

Distribution of HLA-DQA, -DQB and -DPB alleles in ninety-six Japanese patients with melanoma was analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, and the association between clinical parameters and the presence of certain HLA class II alleles investigated. The frequency of HLA-DQB1*0302 was increased, while those of DQA1*0101(04), -DQA1*0401 and DRB1*0802 were decreased in melanoma patients compared with controls. Moreover, the frequency of HLA-DQA1*0103 in patients with acral lentiginous melanoma was increased compared with controls. However, none of these HLA class II alleles showed significant positive or negative associations after correction of the P value. In addition, there was no correlation between these antigens and clinical parameters. These results indicate that HLA class II alleles may not contribute to a strong susceptibility to melanoma in the Japanese.

Adult↗
PubMed1997

New technique for inducing reversible obstructive jaundice in the rat.

We present a new animal model of reversible obstructive jaundice, in which two polyethylene tubes were inserted into the common bile duct, one towards the liver and the other towards the duodenum. The ends of the tubes were tunneled subcutaneously and tied shut to establish obstructive jaundice. Biliary drainage was achieved without a second laparotomy by connecting the tubes with a 1-cm segment of a 24-gauge needle. Serum concentrations of total bilirubin (TB), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), alkaline phosphatase (ALP), and albumin (Alb.) were measured before and after obstruction and decompression. TB, GOT, GPT and ALP increased and Alb. decreased 7 days after the onset of biliary obstruction. All values normalized 14 days after biliary drainage at the latest. Our model is reproducible and allows for evaluation of biliary decompression. Unlike previous models, it can be used for long-term investigation of chronic obstructive jaundice.

Alanine Transaminase↗
PubMed1997

Characterization of two restriction endonucleases, SenPT14bI and SenPT16I, in standard phage-type strains of Salmonella enteritidis.

Two restriction endonucleases (ENases) were found by screening 38 standard phage strains of Salmonella (S.) Enteritidis. An isoschizomer of SacII ENase that recognizes the sequence 5'-CCGC/GG-3' was identified in S. Enteritidis PT14b, and an isoschizomer of XmaIII ENase (5'-C/GGCCG-3') was found in S. Enteritidis PT16. It is of special interest that the recognition specificities of all known ENases in Salmonella, including those of the S. Enteritidis ENases, are very similar to each other.

Chromatography, Ion Exchange↗
PubMed1997

StyD4I restriction-modification system of Salmonella typhi D4: cloning and sequence analysis.

A plasmid (5.4 kbp) from Salmonella Typhi D4 has been identified as encoding a restriction and modification (R-M) system. DNA fragments (2537 bp) that carried the genes for restriction endonuclease and methyltransferase encoded on the plasmid were sequenced. Two divergently arranged open reading frames of 957 bp for the restriction endonuclease consisting of 318 aa (amino acids) and 1140 bp for the DNA methyltransferase consisting of 379 aa were identified. These sequences were similar to the sequences of the SsoII R-M system, including the interspace between the two genes.

Base Sequence↗
PubMed1997

[Embolization for massive retroperitoneal hemorrhage from adrenal pheochromocytoma: a case report].

A 68-year-old woman was found crouching in the kitchen with severe upper abdominal pain. She entered a state of shock at our emergency clinic. Abdominal computed tomography (CT) scan demonstrated a 3 cm cystic mass dorsal to the pancreas tail accompanied with a hematoma. On angiography, a bleeding from the left middle adrenal artery was identified and embolized for hemostasis. An operation was performed 3.5 months after embolization. Preoperative evaluation showed the tumor to be endocrinologically inactive. Metoclopramide stimulation test was negative, too. Left adrenalectomy was performed uneventfully without intraoperative increase in blood pressure. However, histopathological diagnosis was pheochromocytoma. Transarterial embolization is an effective treatment for adrenal bleeding. In our case, however, embolization might have caused the tumor to be falsely "endocrinologically inactive".

Adrenal Gland Neoplasms↗
PubMed1997

[Relationship between iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid washout ratio and oxygen consumption in normal and ischemic myocardium].

The relationship between oxygen consumption and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) washout at rest and after exercise was investigated in normal and ischemic myocardium. Sixteen healthy volunteers and 14 patients with ischemic heart disease were examined. After injection of 111MBq of 123I-BMIPP, serial single photon emission computed tomography imaging was performed to evaluate washout ratio after 30 min and 1 hour of rest and after exercise. In the volunteers, the mean washout ratio was 3.3 +/- 3.5% after 1 hour of rest and increased during exercise. The exercise washout ratio showed a better correlation with net pressure rate product (net PRP: cumulative values of PRP during exercise) than with the peak PRP. The exercise washout ratio showed a strong correlation with the net PRP in the range from 180 to 300 x 10(3) mmHg. beat/min and a plateau of 10-15%. In the nine ischemic patients with net PRP > or = 300 x 10(3) mmHg.beat/min, the exercise washout ratio values were significantly elevated in normal segments relative to ischemic segments (10.1 +/- 1.9% vs 4.7 +/- 2.9%, p < 0.001). In the five ischemic patients with net PRP < 300 x 10(3) mmHg.beat/min, washout ratio at rest and after exercise did not differ significantly between normal and ischemic segments. 123I-BMIPP washout ratio increased with increased oxygen consumption during exercise in normal myocardium but not in ischemic myocardium. The patient must exercise before fatty acid metabolism can be compared between normal and ischemic myocardium.

Adult↗
PubMed1996

Translocation of PKN from the cytosol to the nucleus induced by stresses.

Effects of environmental stresses on the subcellular localization of PKN were investigated in NIH 3T3, BALB/c 3T3, and Rat-1 cells. The immunofluorescence of PKN resided prominently in the cytoplasmic region in nonstressed cells. When these cells were treated at 42 degrees C, there was a time-dependent decrease of the immunofluorescence of PKN in the cytoplasmic region that correlated with an increase within the nucleus as observed by confocal microscope. After incubation at 37 degrees C following beat shock, the immunofluorescence of PKN returned to the perinuclear and cytoplasmic regions from the nucleus. The nuclear translocation of PKN by heat shock was supported by the biochemical subcellular fractionation and immunoblotting. The nuclear localization of PKN was also observed when the cells were exposed to other stresses such as sodium arsenite and serum starvation. These results raise the possibility that there is a pathway mediating stress signals from the cytosol to the nucleus through PKN.

3T3 Cells↗
PubMed1996

PKN associates and phosphorylates the head-rod domain of neurofilament protein.

PKN is a fatty acid-activated serine/threonine kinase that has a catalytic domain highly homologous to that of protein kinase C in the carboxyl terminus and a unique regulatory region in the amino terminus. Recently, we reported that the small GTP-binding protein Rho binds to the amino-terminal region of PKN and activates PKN in a GTP-dependent manner, and we suggested that PKN is located on the downstream of Rho in the signal transduction pathway (Amano, M., Mukai, H., Ono, Y., Chihara, K., Matsui, T., Hamajima, Y., Okawa, K., Iwamatsu, A., and Kaibuchi, K. (1996) Science 271, 648-650; Watanabe, G., Saito, Y., Madaule, P., Ishizaki, T., Fujisawa, K., Morii, N., Mukai, H., Ono, Y. Kakizuka, A., and Narumiya, S. (1996) Science 271, 645-648). To identify other components of the PKN pathway such as substrates and regulatory proteins of PKN, the yeast two-hybrid strategy was employed. By this screening, a clone encoding the neurofilament L protein, a subunit of neuron-specific intermediate filament, was isolated. The amino-terminal regulatory region of PKN was shown to associate with the head-rod domains of other subunits of neurofilament (neurofilament proteins M and H) as well as neurofilament L protein in yeast cells. The direct binding between PKN and each subunit of neurofilament was confirmed by using the in vitro translated amino-terminal region of PKN and glutathione S-transferase fusion protein containing the head-rod domain of each subunit of neurofilament. PKN purified from rat testis phosphorylated each subunit of the native neurofilament purified from bovine spinal cord and the bacterially synthesized head-rod domain of each subunit of neurofilament. Polymerization of neurofilament L protein in vitro was inhibited by phosphorylation of neurofilament L protein by PKN. The identification and characterization of the novel interaction with PKN may contribute toward the elucidation of mechanisms regulating the function of neurofilament.

Binding Sites↗