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Biomedical subjects

Tsuneo Morishima

Publications and source records attributed to Tsuneo Morishima.

At least 19 recordsLinked to original sources

Rapid detection of Epstein-Barr virus DNA by loop-mediated isothermal amplification method.

BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection.

Child, Preschool↗

Evaluation of apoptosis in Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis.

Epstein-Barr virus (EBV) is known to be a causative agent of hemophagocytic lymphohistiocytosis (HLH). To investigate association of apoptosis in the pathogenesis of EBV-associated HLH, the serum EBV loads, and serum concentrations of soluble tumor necrosis factor receptor 1 (sTNF-R1), soluble Fas ligand, and cytochrome c were examined in 15 patients with EBV-associated HLH and 24 patients with infectious mononucleosis (IM). Levels of sTNF-R1 are known to reflect the biological activity of TNF-alpha and cytochrome c is a specific marker of apoptosis. EBV loads, and concentrations of sTNF-R1 and cytochrome c were significantly higher in patients with EBV-associated HLH than in patients with IM. On the other hand, there were no statistically significant differences in the concentrations of soluble Fas ligand. In patients with EBV-associated HLH, EBV loads, concentrations of sTNF-R1, and cytochrome c were correlated with each other. These results suggest that apoptosis, which is dependent on the EBV load and could be mediated by TNF-alpha, plays a major role in the pathophysiology of EBV-associated HLH.

Apoptosis↗

Clonality analysis by sequence variation of the latent membrane protein 1 gene in patients with chronic active Epstein-Barr virus infection.

Chronic active Epstein-Barr virus (EBV) infection is a severe systemic disease associated with high rates of mortality and morbidity. Recent studies suggest that the clonal expansion of EBV-infected T or natural killer cells plays a crucial role in the pathogenesis of chronic active EBV infection. However, it is not clear whether chronic active EBV infection is truly a monoclonal disorder that originates from one cell. The clonality of EBV was investigated by sequence variation of the latent membrane protein 1 (LMP1) gene, which has a high degree of sequence heterogeneity. Peripheral blood mononuclear cells were obtained from nine Japanese patients with chronic active EBV infection and four with infectious mononucleosis. A carboxyl-terminal region of the LMP1 gene was analyzed by polymerase chain reaction (PCR). The amplified PCR products were subcloned, and 18 clones from each sample were sequenced. Patients with chronic active EBV infection each had two to five different LMP1 nucleotide sequences, whereas patients with infectious mononucleosis each had one to seven different sequences. Patients with chronic active EBV infection and infectious mononucleosis both had one dominant sequence. Longitudinal analysis was performed in four patients with chronic active EBV infection, in whom the dominant strains were found to have remained unchanged for several years. The results suggest that EBV in patients with chronic active EBV infection was polyclonal, although clonal expansion may occur. Collectively, these findings are critical to clarify further the pathogenesis of chronic active EBV infection and aid in the development of effective treatment strategies.

Adolescent↗

Analysis of gene-expression profiles by oligonucleotide microarray in children with influenza.

In order to clarify the mechanism of the host response to influenza virus, gene-expression profiles of peripheral blood obtained from paediatric patients with influenza were investigated by oligonucleotide microarray. In the acute phase of influenza, 200 genes were upregulated and 20 genes were downregulated compared with their expression in the convalescent phase. Interferon-regulated genes, such as interferon-induced protein with tetratricopeptide repeats 2 (IFIT2) and vipirin, were strongly upregulated in the acute phase. Gene ontology analysis showed that immune response genes were highly overrepresented among the upregulated genes. Gene-expression profiles of influenza patients with and without febrile convulsion were also studied. In patients with febrile convulsion, 22 genes were upregulated and five were downregulated compared with their expression in patients without febrile convulsion. These results should help to clarify the pathogenesis of influenza and its neurological complications.

Acute Disease↗

Antipyretics and delirious behavior during febrile illness.

BACKGROUND: The purpose of the present paper was to study the use of antipyretics in children with delirium associated with fever in order to clarify their possible adverse effects. METHODS: The use of antipyretics was investigated in 26 children with delirious behavior associated with fever. Temporal relation between delirious behavior and the use of antipyretics was recognized in six children. RESULTS: In four children, delirious behavior was observed soon after administration of antipyretics. The antipyretics used were acetaminophen in two children, mephenamate in one, and diclofenac in one. In the other two children, delirious behavior was observed when body temperature began to fall 1-2 h after administration of antipyretics. The antipyretics used were acetaminophen in one child and mephenamate in one. CONCLUSION: A temporal relationship between antipyretics and delirious behavior was observed in some patients with febrile delirium. This suggests that antipyretics can be a trigger of delirium.

Acetaminophen↗

Assessment of molecular cytogenetic methods for the detection of chromosomal abnormalities.

Some marker chromosomes and chromosome rearrangements are difficult to identify using G-bands by Giemsa staining after trypsin treatment (G-banding) alone. Molecular cytogenetic techniques, such as spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH), can help to detect chromosomal aberrations precisely. We analyzed the karyotypes in 6 cases of multiple congenital abnormalities and 1 case of spontaneous abortion (case 2). Three cases (cases 1, 6, and 7) had marker chromosomes, and 4 cases (cases 2-5) had chromosomal rearrangements. The karyotypes in cases 1, 2, and 3 were determined using FISH with probes based on the clinical findings and family histories. Spectral karyotyping (SKY) analysis in cases 4-7 showed that this method is useful and saves time. The combination of SKY and FISH analyses defined the range of the ring chromosome in case 7. We demonstrated that a combination of G-banding, FISH, and SKY can be applied effectively to the investigation of chromosomal rearrangement and to the detection of marker chromosome origins. We suggest the use of these methods for prenatal diagnosis, in which the inherent time limitations are particularly important.

Adult↗

Tumor necrosis factor receptor-associated periodic syndrome mimicking systemic juvenile idiopathic arthritis.

BACKGROUND: We report two cases of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) in patients in whom systemic juvenile idiopathic arthritis (JIA) had initially been diagnosed or suspected. One patient, given a diagnosis of systemic JIA, was a 10-year-old boy who had presented with recurrent episodes of spike-fever, skin rash, arthritis, and myalgia. The other patient was his 7-year-old sister, who presented with similar symptoms and was suspected of having systemic JIA. METHODS: Serum levels of soluble tumor necrosis factor receptor super family 1A (TNFRSF1A), TNF-alpha, Interleukin (IL) -6, and C-reactive protein (CRP) were measured in two siblings and JIA patients. In addition, DNA sequencing of the TNFRSF1A gene in two siblings was also performed. RESULTS: A detailed family history showed that their mother had an episode of recurrent fever, arthritis, and myalgia with an increased serum CRP after the delivery of a daughter. Both siblings had serum levels of soluble TNFRSF1A that were below the normal reference range, and that did not reach a level corresponding to that of systemic JIA. On TNFRSF1A gene analysis, a single missense mutation resulting in C30Y was found in both siblings. CONCLUSIONS: Based on the clinical features and the TNFRSF1A mutation, both siblings were given a diagnosis of TRAPS. The serum levels of soluble TNFRSF1A, measured along with the CRP level, may be a useful screening marker for differentiating TRAPS from systemic JIA.

Arthritis, Juvenile↗

Clinical significance of decreased serum concentration of cartilage oligomeric matrix protein in systemic juvenile idiopathic arthritis.

OBJECTIVE: Serum cartilage oligomeric matrix protein (COMP) concentration is elevated in patients with early osteoarthritis and early rheumatoid arthritis, and may be a biomarker of cartilage turnover. We investigated whether serum COMP concentration could be a clinically significant marker of arthritis and/or growth impairment in juvenile idiopathic arthritis (JIA). METHODS: Specimens were collected from 82 healthy blood donors under 22 years of age with no growth impairment who served as healthy controls, and from 24 patients with JIA (6 with oligoarthritis, 10 with polyarthritis, 8 with systemic JIA) presenting with active arthritis. Serum COMP concentration was determined using a human COMP assay kit. RESULTS: Serum COMP concentrations were significantly higher in all controls less than 16 years of age than in all controls aged 16 years or older. There was a significant negative correlation between serum COMP concentration and serum C-reactive protein in patients with JIA. Serum COMP concentrations in patients with systemic JIA were significantly lower than those in controls. CONCLUSION: Serum COMP concentrations in healthy children reflected increased cartilage turnover in the growth phase. Because the serum COMP concentration was decreased in cases of systemic JIA in which growth impairment was pronounced, the systemic inflammation occurring in systemic JIA may have an effect on cartilage turnover, which plays an important role in growth. Serum COMP concentration may prove to be a marker that indicates growth impairment in systemic JIA.

Adolescent↗

Association of virus infected-T cell in severe hepatitis caused by primary Epstein-Barr virus infection.

BACKGROUND: Infectious mononucleosis owing to primary Epstein-Barr virus (EBV) infection sometimes causes hepatitis, which is usually self-limiting with mildly elevated transaminases, but can rarely develop into severe hepatitis with jaundice. OBJECTIVE: To clarify the pathogenesis of severe hepatitis by primary EBV infection. METHODS: We experienced four cases of severe hepatitis with jaundice caused by primary EBV infection. These cases were analyzed virologically and histologically, and compared with infectious mononucleosis patients without jaundice. RESULTS AND DISCUSSION: Using real-time PCR, more EBV-DNA was detected in peripheral blood from patients with severe hepatitis, as compared to those without jaundice. Furthermore, CD3+, CD4+ or CD8+ cells contained more EBV DNA than did other cell populations, indicating that in severe hepatitis, T cells harbor most of the EBV. By contrast, mainly B cells were infected in infectious mononucleosis patients without jaundice. The liver was biopsied in three of the four cases. An in situ hybridization study showed that EBV infected lymphocytes, not hepatocytes. In addition, in one patient, it was confirmed that the infected lymphocytes were CD8+ T cells. These results suggest that a large EBV burden and T cell infection may play major roles in the mechanism of severe hepatitis caused by primary EB virus infection.

Adolescent↗

Analysis of serum soluble CD40 ligand in patients with influenza virus-associated encephalopathy.

CD40 ligand (CD40L) is mainly expressed on activated platelets and CD4+T cells, and it can be cleaved from the cell surface, releasing a soluble CD40L (sCD40L). Most sCD40L is derived from activated platelets. A previous paper revealed that the platelet number of patients with influenza virus-associated encephalopathy (IE) was correlated with the outcome. We determined the utility of sCD40L as a predictor for the prognosis of IE. We measured the serum concentration of sCD40L and the platelet number on the day of hospitalization in 34 patients with IE, 16 with influenza virus-associated febrile seizures (IFS), 19 with influenza virus infection without complications (Flu), and 7 with Epstein-Barr virus (EBV) infection. The serum sCD40L concentrations in IE and IFS were significantly lower than those in controls, Flu, and EBV infections. Serum sCD40L concentrations in the IE group were 0.70+/-0.43 ng/ml for deceased patients, 1.73+/-1.36 ng/ml for those with sequelae, and 3.85+/-2.91 ng/ml for those without sequelae. There was no significant difference in platelet number between IE patients with and without sequelae, while the platelet number of deceased patients with IE was significantly lower than in controls, Flu, and IFS. Serum sCD40L concentration on the day of hospitalization was more correlated with the outcome of IE than platelet number. Our findings suggest that the serum sCD40L concentration during acute IE is important for predicting the prognosis at an early stage.

Blood Platelets↗

Rapid detection of herpes simplex virus DNA in cerebrospinal fluid: comparison between loop-mediated isothermal amplification and real-time PCR.

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method that amplifies DNA with high specificity, efficiency, and speed under isothermal conditions. To evaluate the usefulness of LAMP for diagnosing central nervous system infection with herpes simplex virus (HSV), we compared the LAMP method with real-time PCR, using samples that were previously tested by nested PCR. We examined 69 cerebrospinal fluid (CSF) samples from patients suspected of having HSV infection of the central nervous system. The results of the real-time PCR analysis and nested PCR assay were in complete accord. When nested PCR was regarded as standard, the sensitivity of LAMP was 81%, the specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 90%. Although further improvement is necessary for the wide spread use, the LAMP method might be applicable to diagnosis of HSV infection of the central nervous system.

Adolescent↗

Altered brain penetration of diclofenac and mefenamic acid, but not acetaminophen, in Shiga-like toxin II-treated mice.

It is well accepted that bacterial and virus infections elevate the levels of cytokines in serum and cerebrospinal fluids. Such high levels of cytokines might alter the integrity of the blood-brain barrier (BBB) and/or blood-cerebrospinal fluid barrier (BCSFB), subsequently affecting brain penetration of drugs. However, few reports have addressed this issue. Thus, we investigated brain penetration of cyclooxygenase (COX) inhibitors, commonly used as antipyretics, in mice treated with Shiga-like toxin II (SLT-II) derived from E. coli O157:H7, which significantly elevates cytokine levels. As antipyretics, we used diclofenac, mefenamic acid, and acetaminophen. We found that SLT-II significantly increased the brain-to-plasma concentration ratio (Kp) of diclofenac and mefenamic acid, but not of acetaminophen. Moreover, the Kp of diclofenac and mefenamic acid was increased by probenecid, an anionic compound. These results suggest that efflux anion transporters might be involved in the transport of diclofenac and mefenamic acid. Western blot analysis revealed that SLT-II decreased the expression of organic anion transporter-3, an efflux transporter located on the BBB and/or BCSFB. Taken together, these results suggest that SLT-II and/or SLT-II-stimulated cytokines might change brain penetration of drugs and could possibly increase the risk of their side-effects by altering the expression of transporters.

Acetaminophen↗

Differences between T cell-type and natural killer cell-type chronic active Epstein-Barr virus infection.

Infections of T cells and natural killer (NK) cells play a central role in the pathogenesis of chronic active Epstein-Barr virus (CAEBV) infection. To characterize the virologic and cytokine profiles of T cell-type and NK cell-type infection, 39 patients with CAEBV infection were analyzed. Patients with T cell-type infection had higher titers of immunoglobulin G against early and late EBV antigens, suggesting lytic cycle infection. However, the pattern of EBV gene expression was latency type II; BZLF1, which is a hallmark of lytic cycle infection, could not be detected in any patients, regardless of infection type. Patients with CAEBV infection had high concentrations of proinflammatory, T helper cell type 1, and anti-inflammatory cytokines. The cytokine profile in patients with NK cell-type infection was similar to that in patients with T cell-type infection, but the concentration of IL-13 was high in patients with NK cell-type infection. These findings should help to clarify the pathogenesis of CAEBV infection and facilitate the development of more-effective treatments.

Adolescent↗