Biomedical subjects

Shoichi Chida

Publications and source records attributed to Shoichi Chida.

10 recordsLinked to original sources

PubMed2005

Transient decrease in cerebral white matter diffusivity on MR imaging in human herpes virus-6 encephalopathy.

We report a 16-month-old boy with human herpes virus-6 (HHV-6) encephalopathy showing transient abnormalities of the cerebral white matter on magnetic resonance imaging. Diffusion-weighted imaging (DWI) demonstrated diffuse high signal intensity in the bilateral cerebral white matter areas. The signal changes on DWI subsequently resolved, and cerebral atrophy resulted. The transient decrease in the cerebral white matter diffusivity seen in the present case may reflect axonal involvement secondary to the glial or neuronal damage in HHV-6 encephalopathy.

Atrophy↗

PubMed2005

Vascular lesion in a patient of chronic active Epstein-Barr virus infection with hypersensitivity to mosquito bites: vasculitis induced by mosquito bite with the infiltration of nonneoplastic Epstein-Barr virus-positive cells and subsequent development of natural killer/T-cell lymphoma with angiodestruction.

This report describes a vasculitis and subsequently developing angiodestructive lymphoma in an 11-year-old Japanese-Filipino girl exhibiting mosquito allergy with the background of chronic active Epstein-Barr virus (EBV) infection. She developed necrotic skin ulcer at the site of mosquito bite, and histopathological examination revealed EBV-positive mononuclear cell infiltration throughout the wall of small-sized muscular artery. These EBV-positive lymphoid cells were oligoclonal in Southern blot analysis for EBV terminal repeats. Effectiveness of steroid therapy also supports the nonneoplastic nature. Approximately 1 year later, she developed progressive large skin ulcer without mosquito bites. Microscopically, the angiocentric or angiodestructive pattern of EBV-positive atypical cells supported the diagnosis of extranodal natural killer/T-cell lymphoma. Southern blot analysis revealed the monoclonal neoplastic nature of EBV-positive cells. In contrast to the primary mosquito bite lesion, natural killer/T-cell lymphoma cells exhibited the higher expression of EBV latent membrane protein 1 mRNA and the apparent protein expression detected by immunohistochemistry.

Animals↗

PubMed2005

Consensus JH gene probes with conjugated 3'-minor groove binder for monitoring minimal residual disease in acute lymphoblastic leukemia.

Several approaches for the detection of minimal residual disease (MRD) in childhood acute lymphoblastic leukemia (ALL) have shown the importance of determining the level of MRD precisely. In the present study, we tested a new real-time quantitative polymerase chain reaction (RQ-PCR) strategy with minor groove binder (MGB) technology for immunoglobulin heavy chain gene rearrangements by positioning a MGB probe at the germline JH segments and one of the primers at the downstream introns in combination with an allele-specific oligonucleotide (ASO) primer complementary to the VH-DH or DH-JH junctional region. A MGB probe forms extremely stable duplexes with single-stranded DNA targets, allowing the use of shorter probes for hybridization-based assays. Therefore, it shows positional flexibility. We have designed two novel consensus MGB JH germline probes for analyzing all of the germline rearrangements registered in the V BASE database, and demonstrated that the MRD was detectable with the probes in 17 cases of childhood ALL. The actual copy number for the targets and dynamic changes before and after treatment were almost identical between the JH MGB probe and conventional non-MGB probes in each patient. MGB technology will undoubtedly contribute to MRD-PCR studies of childhood ALL.

Base Sequence↗

PubMed2004

Homologous and heterologous antibody responses to lipopolysaccharide after enterohemorrhagic Escherichia coli infection.

To evaluate antibody responses against lipopolysaccharide (LPS: O157, O26, and O111) in enterohemorrhagic Escherichia coli(EHEC) infection, sera of 24 schoolchildren associated with the Morioka outbreak in 1997 and of 74 sporadic patients suspected of having EHEC infection were examined. Using a positive standard serum, quantitative evaluation of LPS antibodies by an enzyme-linked immunosorbent assay (ELISA) was established. High levels of specific IgM and IgA antibodies against homologous E. coli LPS were present in the acute period and are characteristic of EHEC. This could be used for the serological diagnosis of EHEC infection, except for early infants and the elderly. In addition to the specific homologous response, multiple antibody responses against different serotypes other than those isolated were demonstrated in many cases by qualitative analysis using Western blotting.

Adolescent↗

PubMed2003

Detection of bladder hemangioma in a child by blood-pool scintigraphy.

Bladder hemangioma is a rare cause of gross hematuria. A 5-year-old boy was investigated for recurrent episodes of asymptomatic gross hematuria, but no abnormalities were found. Blood-pool scintigraphy using (99m)technetium-human serum albumin combined with diethylene triamine penta-acetic acid (DTPA) revealed an area of increased activity in the right side of the bladder, which was confirmed by cystoscopy as a bladder hemangioma. Endoscopic laser therapy was used to remove two lesions successfully that were diagnosed histologically as cavernous hemangioma. The patient had no further episodes of hematuria in the 2-year period after this treatment. This case study indicates blood-pool scintigraphy may be a useful technique for detecting bladder hemangiomas.

Child, Preschool↗

PubMed2003

Cardiocirculatory effects of patent ductus arteriosus in extremely low-birth-weight infants with respiratory distress syndrome.

BACKGROUND: Cardiocirculatory effects of hemodynamically significant patent ductus arteriosus (hsPDA) have not been systematically studied in extremely low-birth-weight (ELBW) infants with respiratory distress syndrome (RDS). The objective of the present study was to evaluate the effects of hsPDA on the left ventricular output (LVO) and organ blood flows in ELBW infants with RDS. METHODS: Extremely low-birth-weight infants (birth-weight <1000 g) treated with surfactant for RDS were studied by serial Doppler flow examinations. Doppler flow variables in 19 infants in whom hsPDA developed (hsPDA group) were compared with those in 19 infants without hsPDA matched for gestational age, birth-weight, and postnatal age (non-hsPDA group). All infants in the hsPDA group had pharmacologic closure of ductus arteriosus when hsPDA developed. RESULTS: Before pharmacological closure of PDA, the hsPDA group had significantly higher LVO, lower blood flow volume of the abdominal aorta, and lower mean blood flow velocities in the celiac artery, superior mesenteric artery, and renal artery than the non-hsPDA group. These alterations in the hsPDA group reverted to the levels in the non-hsPDA group after the closure of PDA and had no deleterious effects on the cardiorespiratory status. No significant differences between the groups were found in mean blood flow velocities of the anterior cerebral artery throughout the study period. CONCLUSION: These results indicate that although LVO is increased, the splanchnic and renal blood flows are decreased when hsPDA develops in ELBW infants with RDS. The effects of these alterations of LVO and organ blood flows on the cardiorespiratory course seem to be minor when early pharmacologic closure of PDA is done.

Aorta, Abdominal↗

PubMed2003

A missense mutation (GGC[435Gly]-->AGC[Ser]) in exon 8 of the CYP11B2 gene inherited in Japanese patients with congenital hypoaldosteronism.

OBJECTIVES: To clarify the underlying molecular mechanism of corticosterone methyl oxidase type II (CMO II) deficiency, Japanese patients newly diagnosed with CMO II deficiency were investigated. METHODS: We analyzed the patients' genomic DNA sequence on all 9 exons of the CYP11B2 gene. In addition, restriction fragment length polymorphism (RFLP) analysis and expression studies were performed. RESULTS: The analysis showed that the patients homozygously retained a missense mutation, Gumacr;GC[435Gly]-->Aumacr;GC[Ser], in the CYP11B2 gene. Expression studies indicated that the steroid 18-hydroxylase/oxidase activities of the mutant enzyme were substantially reduced. CONCLUSION: These results support the hypothesis that this mutation causes CMO II deficiency in the patients, and are in accordance with our theory that the partial loss of P-450(C18) activities causes CMO II deficiency.

Amino Acid Substitution↗

PubMed2003

[Efficacy and pharmacokinetics of imatinib mesylate in a child with chronic myeloid leukemia].

A 6-year-old girl with chronic myeloid leukemia (CML) was treated with imatinib 230 mg/m2/day and its pharmacokinetics were investigated. The patient had a complete hematologic response on day 21, but had a minor cytogenetic response and the CML progressed to a blast crisis on day 133. At present, she has maintained complete cytogenetic remission with allogenetic peripheral blood stem cell transplantation. The pharmacokinetics revealed that the maximum concentration (1.4 micrograms/ml); time to maximum concentration (5.1 h); half-life (11.0 h); trough concentration (0.4 microgram/ml); and, area under the concentration-time curve (28.1 micrograms.h/ml) were inferior to those for adult patients in the 400 mg/day group. This observation suggests that a suboptimal plasma concentration might be related to resistance to imatinib and/or blast crisis.

Antineoplastic Agents↗

PubMed2002

Peroxisomal acyl CoA oxidase deficiency.

Three Japanese patients with peroxisomal acyl coenzyme A oxidase deficiency who manifested psychomotor retardation and regression during the late infantile period showed characteristic patterns of demyelination in the ponto- medullary corticospinal tracts and in the cerebellar and cerebral white matter. Molecular investigations revealed 2 novel missense mutations, M278V and G178C.

Acyl Coenzyme A↗

PubMed2002

[Abnormal magnetic resonance imaging in a child with Alice in Wonderland syndrome following Epstein-Barr virus infection].

Characteristic pathologic changes of cranial computed tomography (CT) and magnetic resonance imaging (MRI) have never been reported in "Alice in Wonderland" syndrome (AIWS) caused by Epstein-Barr (EB) virus infection. We present here a 10-year-old girl with AIWS with an abnormal MR finding. During the course of serologically confirmed EB virus encephalopathy, she had distortion of the body image, visual hallucinations and depersonalization characteristic of AIWS. MRI demonstrated transient T2 prolongation and swelling of the cerebral cortex, especially at the bilateral temporal lobes, bilateral cingulate gyrus, right upper frontal gyrus, bilateral caudate nucleus, and bilateral putamen, whereas CT showed no abnormalities. Transient MRI lesions were occasionally reported in patients with EB virus encephalopathy/encephalitis who presented visual illusions and psychotic reactions, although the diagnosis of AIWS was not described. We consider that any patient with symptoms of AIWS should have MRI because the abnormal MRI findings may disappear in a short period.

Brain↗