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Biomedical subjects

I Nakano

Publications and source records attributed to I Nakano.

At least 91 records · Page 5Linked to original sources
PubMed1999

Sporadic amyotrophic lateral sclerosis of long duration mimicking spinal progressive muscular atrophy: a clinicopathological study.

We report an autopsy case of amyotrophic lateral sclerosis (ALS) clinically diagnosed as spinal progressive muscular atrophy (SPMA). The patient was a Japanese woman without hereditary burden. She developed muscle weakness of the distal part of the left lower extremity at age 42, followed by muscle weakness and atrophy of the right lower extremity and upper extremities. At age 57, she needed transient ventilatory support. Slight weakness in the facial muscles and fasciculation of the tongue appeared at age 60. At age 61, she died of sudden respiratory arrest. During the clinical course, neurological examination revealed neither Babinski signs nor hyperreflexia. The neuropathological examination revealed not only neuronal loss with gliosis in the facial nucleus, hypoglossal nucleus, and anterior horns of the spinal cord, but also loss of Betz cells and degeneration of the pyramidal tracts. Based on these clinicopathological findings and review of literature, we conclude that sporadic ALS mimicking SPMA is present.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Astrocytic hyaline inclusions contain advanced glycation endproducts in familial amyotrophic lateral sclerosis with superoxide dismutase 1 gene mutation: immunohistochemical and immunoelectron microscopical analyses.

To clarify the neuropathological significance of the deposition of N(epsilon)-carboxymethyl lysine (CML), an advanced glycation endproduct, in astrocytic hyaline inclusions in familial amyotrophic lateral sclerosis (FALS), autopsy specimens from five members of two different families who had the superoxide dismutase 1 (SOD1) gene mutations were analysed. Immunohistochemically, most of the neuronal and astrocytic hyaline inclusions were intensely stained by the antibody against CML. The distributions and intensities of the immunoreactivities for CML and SOD1 were similar in the inclusions in both cell types. Immunoelectron microscopy showed that both inclusions consisted of CML-positive granule-coated fibrils and granular materials. No significant CML or SOD1 immunoreactivity was observed in the neurons and astrocytes of the normal control subjects. Our results suggest that astrocytic hyaline inclusions contain CML and SOD1 in FALS patients with SOD1 gene mutations, and that the formation of CML-modified protein (probably CML-modified SOD1) is related to the cell degeneration.

Adult↗
PubMed1999

Breached cerebral glia limitans-basal lamina complex in Fukuyama-type congenital muscular dystrophy.

We have reported breaches of glia limitans (GL)-basal lamina (BL) complex with protruding neuroglial tissue in Fukuyama-type congenital muscular dystrophy (FCMD) fetus brain and suggested that some basic deficits in the GL-BL complex may have a pivotal role in formation of micropolygyria in FCMD. We therefore investigated the cerebral GL-BL complex in seven FCMD cases (12-27 years of age), in three cases of Duchenne muscular dystrophy (17-25 years of age) and in two non-neurological controls (28 and 33 years of age). The frontal lobe cortex was examined immunocytochemically using antibodies against collagen type IV and laminin in each case, and ultrastructurally in an adult case of FCMD. In FCMD, the BL of the cortical surface was frequently breached with protruding neural tissue that ultrastructurally showed frequent synapses, neurites that had parallel arranged microtubules, and astrocytic processes. The outermost surface of this tissue was only partly lined by a BL. In the region of the gyral adhesion of micropolygyria, the perivascular space of the apparently entrapped meningeal blood vessels was occupied by neuroglial tissue, which is assumed to have invaded through the occasionally seen breaches of the perivascular GL-BL complex. Electron microscopy of the intruding tissue showed frequent synapses, microtubule-containing neurites and astrocytic processes. No breached GL-BL complex was found in any of the non-FCMD cases. These findings indicate that in FCMD, the cerebral GL-BL complex continues to have a crucial deficit with resulting breaches through which neuroglial tissue protrudes, promoting adhesion of the adjacent cerebral gyri during brain development before and after birth.

Adolescent↗
PubMed1999

Why is the interferon sensitivity-determining region (ISDR) system useful in Japan?

BACKGROUND/AIMS: The amino acid sequence of NS5A2209-2248, named the "interferon sensitivity-determining region" (ISDR), has been reported to correlate with responsiveness of interferon (IFN) therapy to patients with the hepatitis C virus (HCV) genotype-1b, by several Japanese authors. However, European authors have failed to find this phenomenon, suggesting a difference in HCV-1b isolates between Japan and Europe. METHODS: We compared the HCV-1b nucleotide sequences of our Japanese patients and those of other countries quoted from GenBank, using the envelope 1 sequence. RESULTS: A phylogenetic tree analysis revealed two characteristic groups from a geographical viewpoint: one group (NJ group) consists of almost entirely non-Japanese isolates, and the other (J group) of almost entirely Japanese isolates. The isolates other than the NJ and J groups are characterized by their specific nucleotide residue, constructing an individual group (W group). Japanese HCV-1b isolates consist of the J group and W group (approximately 40% and 60%, respectively). Comparative study between the two groups in Japanese patients treated with IFN revealed a strong correlation between ISDR type and IFN responsiveness only in the J group, but not in the W group. CONCLUSIONS: These observations convinced us that the existence of the Japan-specific J group is one reason why the ISDR system is useful only in Japan.

Base Sequence↗
PubMed1999

Infection with TT virus, a novel transfusion-transmissible DNA virus, in haemophiliacs and in blood products.

We evaluated the characteristics and rate of infection with TT virus (TTV), a novel DNA virus, in Japanese haemophiliacs. TTV DNA was measured in 60 haemophiliacs by semi-nested polymerase chain reaction. Co-infection with hepatitis C virus (HCV), hepatitis G virus (HGV) and human immunodeficiency virus (HIV) was also evaluated. In addition, the rate of detection of TTV DNA in blood products was evaluated. TTV DNA was detected in 35/60 haemophiliacs (58.3%). There were no differences in the backgrounds or characteristics between haemophiliacs with and without TTV infection, except for higher levels of IgG and IgM in patients with TTV infection. In patients infected with TTV of types other than type 1, which are rarely detected in Japan, the rate of co-infection with HCV of imported types was high; TTV of types other than type 1 in Japanese haemophiliacs were probably transmitted by imported blood products. TTV DNA was detected in over half of the blood products tested, but TTV DNA concentrations in these products were lower than in the serum of haemophiliacs.

Adolescent↗
PubMed1999

Reactive lymphoid hyperplasia of liver coexisting with chronic thyroiditis: radiographical characteristics of the disorder.

BACKGROUND: Reactive lymphoid hyperplasia of the liver is an extremely rare entity, with six cases reported so far. METHODS: We encountered a 47-year-old Japanese female with reactive lymphoid hyperplasia of the liver, which coexisted with chronic thyroiditis. The lesion was discovered incidentally as a hypo-echoic mass with a hyper-echoic rim at a routine ultrasonography examination. It increased from 12 to 17 mm diameter in 6 months. Radiological studies, such as contrast-enhanced computerized tomography (CT) and angiography demonstrated a hypervascular lesion. RESULTS: It was consequently diagnosed as a neoplasm with malignant potentiality and she underwent partial hepatectomy. The lesion was composed of small mature lymphocytes which formed prominent lymphoid follicles with germinal centres, scattered plasma cells and stromal fibrosis. Immunohistochemical study revealed polyclonal origins of the involved lymphocytes. DNA analysis for the immunoglobulin heavy gene and the T cell receptor beta gene using Southern blot hybridization showed no monoclonality. The following features have characterized the images in past cases, as well as ours: hypo-echoic mass, occasionally with a rim, in ultrasonography and hypervascularity, shown by angiography and enhanced CT.

Angiography↗
PubMed1999

Effect of pancreastatin on cerulein-stimulated pancreatic blood flow and exocrine secretion in anaesthetized rats.

BACKGROUND: Pancreastatin (PST) is an inhibitor of pancreatic exocrine secretion in vivo but not in vitro, which suggests that the inhibitory effect of PST is indirect, that is, not mediated by a specific receptor on pancreatic acinar cells. In this study, we investigated the effects of PST on pancreatic exocrine secretion and local pancreatic blood flow in anaesthetized rats to elucidate the participation of PST in indirect regulation of pancreatic exocrine function through blood supply. METHODS: Pancreastatin (100, 200 or 500 pmol/kg per h) was administered intravenously under background infusion of cerulein (0.5 microg/kg per h), a cholecystokinin analogue. Pancreatic exocrine secretion was monitored by volume and protein output of the pancreatic juice and local pancreatic blood flow was measured by the hydrogen gas clearance method. RESULTS: Pancreastatin significantly reduced cerulein-induced local pancreatic blood flow in a dose-dependent manner. Pancreatic exocrine secretion was also reduced significantly by PST dose-dependently. Pancreastatin did not change systemic blood pressure. These results suggested that the reduction of pancreatic blood flow is associated with the reduction of pancreatic exocrine secretion. CONCLUSIONS: We conclude that the mechanism of PST-induced inhibition of pancreatic exocrine secretion is, at least, partly mediated by the reduction of local pancreatic blood flow through blockade, caused by the action of cerulein on pancreatic blood flow.

Animals↗
PubMed1999

Conformational epitopes detected by cross-reactive antibodies to envelope 2 glycoprotein of the hepatitis C virus.

The prevalence of anti-E2 antibody in persons chronically infected with hepatitis C virus (HCV) is high irrespective of viral genotype, and this cross-reactive antibody is thought to react with a conformational epitope. To investigate the characteristics of this anti-E2 antibody, the immunoreactivity of sera from HCV-1b-infected patients was measured against various modified forms of E2 glycoprotein derived from HCV-H (genotype 1a) by an immunofluorescence technique. Twelve of 18 patients were positive for anti-E2 antibody, and 10 of the 12 required a minimal amino acid (aa) region including aa 406-644 for strong reactivity, suggesting that the major E2 antibody has a conformational epitope in this region. Subsequent analysis using mutant E2 glycoproteins designed to lose N-glycosylation potential at varying sites revealed seven important N-glycosylation sites in this region. Four of these (aa 423, 430, 448, and 576) are indispensable for an antibody response.

Amino Acid Sequence↗
PubMed1999

Single sperm analysis of the CAG repeats in the gene for dentatorubral-pallidoluysian atrophy (DRPLA): the instability of the CAG repeats in the DRPLA gene is prominent among the CAG repeat diseases.

Dentatorubral-pallidoluysian atrophy (DRPLA) is known to show the most prominent genetic anticipation among CAG repeat diseases. To investigate the mechanism underlying the meiotic instability of expanded CAG repeats in the gene for DRPLA, we determined the CAG repeat sizes of 427 single sperm from two individuals with DRPLA. The mean variance of the change in the CAG repeat size in sperm from the DRPLA patients (288.0) was larger than any variances of the CAG repeat size in sperm from patients with Machado-Joseph disease (38. 5), Huntington's disease (69.0) and spinal and bulbar muscular atrophy (16.3), which is consistent with the clinical observation that the genetic anticipation on the paternal transmission of DRPLA is the most prominent among CAG repeat diseases. The variance of the change in CAG repeat size was significantly different between the two DRPLA patients (F-test, P < 0.0001). However, the segregation ratio of single sperm with an expanded allele to ones with a normal allele is not statistically different ( P = 0.161) from the expected 1:1 segregation ratio, and thus segregation distortion of expanded alleles in meiosis in male patients with DRPLA was not demonstrated.

Alleles↗
PubMed1999

Interferon treatment of two patients with quadruple infection with hepatitis C virus (HCV), human immunodeficiency virus (HIV), hepatitis G virus (HGV), and TT virus (TTV).

We administered interferon (IFN) to two patients who had quadruple infection with hepatitis C virus (HCV), human immunodeficiency virus (HIV), hepatitis G virus (HGV), and TT virus (TTV), a recently isolated novel DNA virus. Nine mega-units of natural alpha-IFN were administered daily during the first two weeks and thrice weekly during the following 22 weeks (total dose, 720 mega-units). In both cases, serum alanine aminotransferase (ALT) levels decreased during IFN administration but increased thereafter. The concentrations of HCV, HIV, HGV, and TTV declined with the administration of IFN. However, the concentrations of these 4 viruses increased after the cessation of IFN with the except of TTV in patient 2 which disappeared during treatment and did not subsequently reappear. IFN reduced the concentrations of 4 viruses, in an apparently independent manner.

Adult↗
PubMed1999

A novel synthetic anti-acute pancreatitis agent, IS-741.

A novel synthetic drug, IS-741, inhibited cell adhesion in vitro and neutrophil in vivo. Thus, IS-741 inhibited the magnification of pancreatic lesion as well as progression to multiple organ failure in acute pancreatitis models. Furthermore, IS-741 at identical plasma concentrations equally improved the survival rates in animals of various species with severe acute pancreatitis. Based on these observations, it was considered that IS-741 inhibited tissue destruction by neutrophil after inhibiting neutrophil infiltration into the pancreas or other important organs in acute pancreatitis. It was also considered that IS-741 demonstrated various anti-acute pancreatitis effects by interrupting a vicious cycle of inflammation. Therefore, IS-741 is expected to become a useful drug for treating acute pancreatitis and multiple organ failure in clinical settings.

Acute Disease↗
PubMed1999

Fatal liver failure in haemophiliacs with HIV-induced immunodeficiency: observation of six patients.

We observed six cases of haemophiliacs with HIV-induced immunodeficiency who died from fatal liver failure despite the absence of evident cirrhosis. They all had the infection with hepatitis viruses (two patients with hepatitis B and D viruses and four patients with hepatitis C virus) and their CD4 counts were severely decreased. They were much younger than cirrhotic haemophiliacs without HIV. Their serum levels of hyaluronic acid and type IV collagen were lower than those in haemophiliacs with cirrhosis, and were normal. No patients had experienced symptoms or concomitant diseases characteristic of cirrhosis, such as ascites, jaundice, oesophageal/gastric varices or hepatocellular carcinoma, except for one case who had a history of mild ascites. The characteristics of this liver failure were different from liver failure resulting from cirrhosis caused by chronic hepatitis, which suggests liver failure that is specific to patients with immunodeficiency. This kind of liver failure can be a factor threatening survival in patients with HIV infection and with hepatitis virus co-infection in an immunodeficient state.

Acquired Immunodeficiency Syndrome↗