Search PubMed⌕ Search

Biomedical subjects

H Ushijima

Publications and source records attributed to H Ushijima.

At least 37 records · Page 2Linked to original sources
PubMed2001

Characterization of cell-surface determinants important for baculovirus infection.

Baculovirus gp64 envelope glycoprotein is a major component of the envelope of the budded virus and is involved in virus entry into the host cells by endocytosis. To investigate the cell-surface molecules important for infection of baculovirus into mammalian cells, we constructed a recombinant baculovirus, Ac64-CAluc, which has gp64 and luciferase genes under the polyhedrin and the CAG promoter, respectively. For controls, we constructed recombinant viruses possessing vesicular stomatitis virus (VSV) G protein, mouse hepatitis virus (MHV) S protein, or green fluorescent protein (GFP) gene under the polyhedrin promoter and the luciferase gene under the CAG promoter (AcVSVG-CAluc, AcMHVS-CAluc, and AcGFP-CAluc). Treatment of HepG2 cells with phospholipase C markedly reduced the reporter gene expression by Ac64-CAluc or AcVSVG-CAluc in a dose-dependent manner, whereas AcMHVS-CAluc was shown to be resistant to the treatment. Inhibition with purified lipids and susceptibility to the mutant CHO hamster cell lines deficient in phospholipids synthesis suggest that the interaction of gp64 and phospholipids on the cell surface might play an important role in baculovirus infection into mammalian cells.

Animals↗
PubMed2001

Genetic analysis of the capsid region of astroviruses.

Eight serotypes of human astroviruses (HAstV-1 to HAstV-8) have been described. To date, the entire genomes of HAstV-1 and HAstV-2 as well as the ORF2 sequences of HAstV-1-6 and 8 have been reported. In this study, the ORF2 sequences of seventeen strains of HAstVs originating from different countries were determined, as well as the sequence ORF2 of one porcine astrovirus (PAstV) strain. Afterwards, comparison of the capsid protein precursors encoded by ORF2 of 46 strains of HAstVs, PAstV, and feline astrovirus (FAstV) was carried out. A phylogenetic tree showed eight genogroups of HAstVs that corresponded exactly to the serotypes. HAstV-3 and 7 were the most closely related, whereas HAstVs, FAstV, and PAstV segregated from each other. Compared to a PAstV, a FAstV is closer to HAstVs. Furthermore, the capsid protein precursors were divided into four regions (after amino acid residues 424, 688, and 776, respectively) based on sequence identity. Region I was the most conserved, and FAstV was very close in identity to HAstVs. Two amino acid motifs in region I were predicted to contain the common antigenic epitopes. Region II was relatively variable. Deletions and insertions were characteristic of region III, and region IV was relatively conserved. To our knowledge, this is the first comparative sequence analysis of the capsid protein precursors of eight serotypes of HAstVs as well as two animal astroviruses (FAstV and PAstV).

Amino Acid Motifs↗
PubMed2001

Child behavior problems: prevalence and correlates in rural minority areas of China.

BACKGROUND: Ethnicity may possibly associate with different maternal child-rearing practices and child developmental problems. The aim of this study was to better understand epidemiological features and correlates of child behavior problems in a large sample of children in economically disadvantaged rural minority areas of China and to provide reference data for subsequent intervention of child developmental problems. METHODS: A total of 1222 rural mother-child pairs belonging to Hani, Yi, Hui, Miao and Han were drawn from four economically disadvantaged minority counties in Yunnan Province of China. Well-trained investigators completed child physical examination and measurements (height and weight) in village clinics and interviews of mothers at respondents' homes using a structured questionnaire. RESULTS: Child behavior problems were prevalent in children aged 2-6 years: 71.4% for temper tantrums; 48.2% for swearing; 36.0% for nocturnal bed-wetting; 29.9% for disobedience; 29.5% for difficulty initiating sleep; and 17.0% for picky eating. Child behavior problems significantly differed across Hani, Yi, Hui, Miao and Han ethnic groups. Logistic regression indicated that ethnicity of Hui compared with Han, younger children, prenatal risk factors, being a twin, ineffective child-rearing behaviors such as pampering, corporal punishment, swaddling, family disagreement among child-rearing contributed independently to the risk for child behavior problems. CONCLUSIONS: The child behavior problems were prevalent in children aged 2-6 years in rural minority children of China. Ineffective family child-rearing practices increase risk for child behavior problems.

Child↗
PubMed2001

Molecular characterization in the VP7, VP4 and NSP4 genes of human rotavirus serotype 4 (G4) isolated in Japan and Kenya.

The VP7, VP4 and NSP4 genes of human rotavirus serotype 4 (G4) were analyzed to investigate intraserotypic variations. The techniques used included reverse transcription polymerase chain reaction with subtype specific primers, restriction fragment length polymorphism analysis and sequence analysis. Twelve isolates (nine from Japan and three from Kenya) and two standard strains (Hochi, Odelia) were G4A P[8] Wa group NSP4. A standard strain (ST3) was G4A P[6] Wa group NSP4 and a strain (VA70) was G4B P[8] Wa group NSP4. These results show G4 rotaviruses can be divided into three combinations at the moment.

Antigens, Viral↗
PubMed2001

Immunomodulatory effect of gold sodium thiomalate on murine acquired immunodeficiency syndrome.

Induction of IL-2 production and increased expression of CD25 were observed in C57BL/10 mice after weekly treatment with gold sodium thiomalate (GST). LP-BM5 murine leukemia virus (MuLV) infected mice treated with GST survived longer, had less cervical lymph node swelling, lower spleen weight, and fewer abnormalities in the expression of the cell surface markers, CD4, CD8a and CD45R/B220 on spleen cells than those that were not treated with GST. Thus, GST treatment may be beneficial through a decrease in disease progression via IL-2 induction in MuLV infected mice. This may have application in human immunodeficiency virus-infected individuals.

Animals↗
PubMed2001

[Evaluation of immunochromatography based rapid detection kit of rotavirus and adenovirus].

We investigated the usefulness of Rapidtesta Rota-Adeno (Daiichi Pure Chemicals Co., Ltd., Japan) for rapid detection of group A rotavirus and adenovirus simultaneously using immunochromatography with clinical samples. In investigation of the reaction of the kit to 5 strains of group A rotavirus, 13 strains of adenovirus and other intestinal viruses, specific lines were formed in red to group A rotavirus and blue to adenovirus. No cross reaction was observed with other intestinal virus. In measurement of detection limit, group A rotavirus (SA11) was detected at 10(4.4)TCID50/ml, serotype 3 adenovirus at 10(4.45)TCID50/ml. The detection limit of the kit was similar to other immunochromatographic assay or enzyme immnoassay kits and approximately 10 times higher than that of kits using latex agglutination test. In comparison with other testing kits in clinical samples, the concordance with other immunochromatographic assay was 99.2% (121/122) in group A rotavirus and 98.6% (138/140) in adenovirus. The rate of concordance with latex agglutination test kit was 94.5% (69/73) in group A rotavirus and 92.3% (84/91) in adenovirus. The kit had high rates of concordance with other immunochromatographic assay kits and higher virus detection rates than those of latex agglutination test kits. Rapidtesta Rota-Adeno is able to detect group A rotavirus and adenovirus simply and rapidly. In addition, the two kinds of virus can be easily differentiated by color difference in reaction lines, suggesting that the kit is useful in clinical diagnosis.

Adenoviridae↗
PubMed2001

Effect of steroid-liposome on immunohistopathology of IgA nephropathy in ddY mice.

Immunopathological studies were performed to determine whether glomerular injuries in ddY mice, a spontaneous animal model for IgA nephropathy, are influenced by treatment with a newly developed liposome loaded with prednisolone phosphate (PSL-liposome). The newly synthesized novel cationic lipid 3,6-dipentadeciroxy-1-amizino-benzene (TRX-20) was employed to obtain selective affinity to the anionic cell surface and extracellular matrices in glomerular mesangial lesions. ddY mice were treated intravenously with 1.0 mg/kg of PSL-liposome once a week for 16 weeks (from 45 weeks to 61 weeks of age). ddY mice were also intravenously treated with 1.0 mg/kg of ordinary PSL once a week for the same duration. On immunofluorescence, depositions of IgA and C3 in the glomerular mesangial areas and capillary walls of PSL-liposome-treated ddY mice were markedly decreased as compared with those of ordinary PSL-treated and untreated control ddY mice. The mean intensity of IgA and C3 in glomeruli of PSL-liposome-treated ddY mice was decreased as compared with that in ordinary PSL-treated and untreated control ddY mice. Glomerular mesangial expansion in PSL-liposome-treated ddY mice was milder than that found in ordinary PSL-treated ddY mice or untreated control ddY mice. It appears that treatment with PSL-liposome is effective in improving glomerular IgA and C3 depositions and glomerular expansion in IgA nephropathy of ddY mice.

Animals↗
PubMed2001

Rapid detection and typing of oculopathogenic strain of subgenus D adenoviruses by fiber-based PCR and restriction enzyme analysis.

PURPOSE: To develop a new detection and typing method of oculopathogenic strains of subgenus D adenoviruses directly from conjunctival scrapings by a combination of polymerase chain reaction (PCR) and restriction enzyme analysis (REA). METHODS: A new PCR method using primer pairs of AF2/AR2, which are specific for the fiber genes, were developed to amplify 1150-bp products from nine oculopathogenic prototypes of subgenus D adenoviruses. Amplicons were cleaved with three restriction enzymes: DdeI, HinfI, and RsaI. Clinical specimens of 102 conjunctival scrapings were also evaluated by this PCR method. Restriction patterns of prototypes were used for the typing of clinical samples. Detection limit was determined by the PCR amplification of a known amount of purified adenovirus serotype 8 DNA. RESULTS: A novel PCR method based on the fiber genes allowed the amplification of nine oculopathogenic serotypes of subgenus D (Ad8, Ad9, Ad15, Ad17, Ad19, Ad22, Ad28, Ad37, and Ad39). As little as 38.4 fg of adenovirus type 8 could be detected by this method. Positive results were obtained from 48 of 102 samples (47%) by both hexon- and fiber-based PCR, whereas only 29 of 102 (28.4%) yielded positive results by culture isolation/neutralization test (NT). All positive specimens (29 samples) of culture isolation and PCR-RFLP methods showed positive results by our new fiber-based PCR method, and no positive products were detected from other subgenus of adenovirus or nonadenoviral DNA. CONCLUSIONS: A newly developed fiber-based PCR-REA method for the detection and typing of adenoviruses is faster than any former PCR methods. This all-in-1-day detection and typing method will be quite useful to the rapid diagnosis of subgenus D adenovirus infection.

Adenovirus Infections, Human↗
PubMed2001

Characterization of human rotavirus serotype G9 isolated in Japan and Thailand from 1995 to 1997.

Serotyping of human rotavirus was conducted in 396 Japanese and 100 Thai rotavirus-positive fecal specimens collected from 1995 to 1997. Serotype G9 was found to be the third most common serotype with frequency of 16.2% in Thailand from 1996 to 1997. It was also detected in Japan with a low frequency (0.7%) in this year. The genetic analyses of VP4 and NSP4 genes of these G9 strains showed that 1 strain from Japan possessed P[8] genotype and NSP4 Wa-group with long electropherotype (e-type). In contrast, 5 strains from Thailand belonged to P[6] and 1 strain belonged to P[4]. All of the Thai strains were in the NSP4 KUN-group with a short e-type. Sequence analysis of their VP7 gene revealed that there was the highest homology among fecal G9 strains (> 96.3%, amino acid identity) and a relatively high degree of homology to standard viruses, F45 from Japan (95.4-96.3%, amino acid identity) and 116E from India (92-92.3%, amino acid identity). However, immunological analysis using G9 specific monoclonal antibodies (Mabs) against VP7 protein showed that the G9 strains isolated from the two countries had different antigenic specificity. It was confirmed further by intraserotypical phylogenetic analysis of VP7 amino acid. These results indicated that the prevalence of G9 rotavirus in 1996-1997 in Thailand was relative to the continuing recent emergence of it on a worldwide basis, while the Japanese G9 strain isolated in this survey was identified to have progenitors common to the F45 strain that was prevalent in 1985 in Japan. Phylogenetic analysis of VP7 amino acid of G1-14 prototype rotavirus showed that the G9 strains were most closely related to the equine G14 rotavirus FI23 strain but G3 strains, interserotypically. These findings suggest that G9 rotaviruses might be divided into two or more subtypes.

Adolescent↗
PubMed2000

Novel approaches in diagnosis and therapy of Creutzfeldt-Jakob disease.

The scrapie prion protein, PrP(Sc), as well as its peptide fragment, PrP106-126, are toxic on neuronal cells, resulting in cell death by an apoptotic, rather than necrotic mechanism. The apoptotic process of neuronal cells induced by prion protein supports diagnosis and offers potential targets for therapeutic intervention of the prion diseases. Among the cerebrospinal fluid (CSF) proteins, which may serve as markers of neuronal cell death associated with prion diseases, the 14-3-3 protein(s) turned out to be the most promising one. A new sensitive assay allows the detection of even small changes in the normally low levels of these proteins. In vitro, the toxic effects displayed by PrP(Sc) and its peptide fragment can be blocked by antagonists of N-methyl-D-aspartate (NMDA) receptor channels, like Memantine. Also Flupirtine, a non-opiod analgesic drug, which is already in clinical use, was found to display in vitro a strong cytoprotective effect on neurons treated with PrP(Sc) or PrP106-126. This drug acts like a NMDA receptor antagonists, but does not bind to the receptor. Clinical trials on prion diseases with Flupirtine are in progress. Flupirtine was found to enhance the intracellular levels of the antiapoptotic protein Bcl-2 and the antioxidative agent glutathione (GSH). Due to its favourable pharmacokinetic profile, Flupirtine is considered to be a promising drug to prevent neuronal death in Creutzfeldt-Jakob disease (CJD) and other neurodegenerative disorders occurring with age, e.g. Alzheimer's disease.

Animals↗
PubMed2000

Selective binding of hepatitis C virus core protein to synthetic oligonucleotides corresponding to the 5' untranslated region of the viral genome.

Although it is assumed that hepatitis C virus (HCV) core protein binds with viral RNA to form a nucleocapsid, little is known about the resulting molecular interactions. We utilized surface plasmon resonance technology to study the structural basis of the affinity and the preference of the interaction between HCV core protein and oligonucleotides derived from the viral genome. Among the 10 oligonucleotides corresponding to the 5' untranslated region (5'UTR) of the tested HCV genome, the real-time analysis of sensorgrams indicated that the core protein binds most efficiently and stably to the 31-nucleotide-long sequence of the loop IIId domain, whose secondary structure is highly conserved not only among different HCV genotypes but also among pestiviruses. There also could be some interactions of the core protein with the loop I domain and the region of nt 23-41. The kinetic profiles, together with those obtained in experiments using single- and double-stranded polymeric oligonucleotides, suggest a multimerization of the core protein in solution. These newly characterized properties could provide a basis for understanding the pathway of the viral nucleocapsid assembly.

5' Untranslated Regions↗
PubMed2000

Infantile convulsions with mild gastroenteritis.

The development of sensitive new molecular genetic techniques has led to the detection of rotavirus in cerebrospinal fluid, stools and throat swabs from patients with gastroenteritis with accompanying clinical symptoms similar to infantile benign convulsions. Small round structured virus (SRSV) has also been found in stools of patients with similar clinical symptoms by a new procedure. However, the mechanism by which these viral infections induce benign convulsions remains to be elucidated. The present paper reviews recent virological and clinical studies of seizures probably caused by gastroenteritis viruses including rotavirus, SRSV and other viruses.

Caliciviridae Infections↗
PubMed2000

Rotavirus infection in children in Japan.

Currently, a high morbidity of rotavirus diarrhea has been seen in children in developed and developing countries. Improvement of the vaccines is necessary in order to reduce the burden of diarrhea caused by rotavirus. A survey of rotavirus infection from diarrheal stool specimens in children of seven regions in Japan was conducted from 1984 to 1999. The present study discusses the survey results and reviews the national and international data of more than 23 papers and congress proceedings about rotavirus infection in Japan. We analyze the prevalence of rotavirus infection in acute diarrheal in- and outpatients, the distribution of rotavirus G-serotypes and surveillance data for seasonality and age groups in Japan. The data indicated that rotavirus is the most important cause of diarrhea in Japan among young children, with the prevalence ranging from approximately 9.7 to 88%. The most common rotavirus strains belonged to serotype G1, specifically since 1993. Serotypes G2, G3 and G4 had also been documented to be predominantly based in the area and year before 1992. However, untypeable rotavirus strains had been found each year, with a prevalence up to 56.7% which suggests that rare serotypes (except G1-4) or new serotypes might exist. Unexpectedly, in Tokyo and Sapporo from 1998 to 1999, G9 was found to be the first most prevailing serotype with a high prevalence of 52.9 and 71.4%, respectively. Despite these data from different geographic areas, the year under investigation was relatively clear in respect to seasonality, with a peak of rotavirus activity in late winter (February) through early spring (March). Age distribution had also characterized that the infection was predominant among children aged 1-2 years of age, although it was also common in children of 2-3 years. In addition, mixed infection with bacteria was documented.

Adolescent↗
PubMed2000

Development of antirotavirus agents in Asia.

Human rotaviruses are the major etiologic agents of diarrhea in infants and young children under 2 years of age worldwide. Rotavirus diarrhea is a life-threatening disease for children; many efforts are made to reduce the morbidity and mortality in Asia. To date many natural compounds and some Western medicines have exhibited their antirotavirus effects in clinical studies, in animal experiments and in vitro. Compared with antirotavirus agents in the USA and Europe, natural compounds have been identified as ideal candidates for antirotaviral drugs in Asia because they are cheaper and effective, have no side-effect and no toxicity. We have attempted to reveal the antirotavirus mechanism of some natural compounds. We found that cacao pigment, tea extract and pine seed shell extract inhibit rotavirus adsorption to cells while cacao pigment may also inhibit rotavirus reproduction in vitro. The usage of antirotavirus agents in Asia demonstrated that additional effective approaches to control rotavirus infection, such as antirotavirus agents, are necessary, in particular for the children with rotavirus diarrhea who have severe complications.

Antiviral Agents↗
PubMed2000

Epidemiology of rotavirus infection in Thailand.

Rotavirus is a major cause of acute severe diarrhea in children worldwide and an important cause of death among young children in developing countries. Group A rotaviruses are antigenically complex and multiple serotypes infect humans. Reassortant rotavirus vaccines are now available which offer protection against severe illness caused by rotavirus serotypes G1-4. Before vaccines are introduced into target populations, it is necessary to establish the baseline data of the epidemiology of rotavirus infection in those countries. The purpose of the present study is to provide information related to the epidemiology of rotavirus infection in Thailand. All rotavirus studies performed in Thailand were found through Medline and Thai Index Medicus searches. A total of 26 of the most relevant studies published in international and national journals are reviewed. Most studies reported that the prevalence of rotavirus infection in Thailand was 27-34%, although a few studies have reported a prevalence above this range. The peak seasonal distribution of rotavirus infection among children hospitalized with diarrhea in Thailand was seen in the dry cool seasons: October to February. The prevalence of rotavirus infection was most frequently found in children aged 6-11 months up to 2 years. G1 was the most prevalent serotype in Thailand, followed by G2, G4 and G3, respectively. At least three G serotypes, mostly G1, G2 and G4, are seen to coexist in Thailand each epidemic year and in some studies all four G-serotypes were reported in the same epidemics. In a 1996-1997 study, G9 was the third prevailing serotype after G1 and G2, respectively. These results indicate that rotavirus epidemics occur in Thailand every year and children are the most affected population. In Thailand, although G1-G4 have been reported, G1 is the most prevalent serotype in each epidemic and G9 is becoming increasingly common.

Age Factors↗
PubMed2000

Development of a simple and rapid latex test for rotavirus in stool samples.

In the fields of infectious diseases, a variety of immunoassay methods has been reported. More simple, rapid and cost-effective manual tests for infectious diseases are needed. For the purpose of simple diagnosis of rotavirus infection, a rapid test against human rotavirus was developed. As for the preparation of the reagent, clinically isolated human rotavirus was cultured using MA-104 cells. Then, the cultured virus was purified by an ultracentrifugation method. The purified virus was inactivated with formaldehyde for use as antigen for immunization of rabbits. The antibody was purified and applied to sensitize the surface of latex particles to react with rotavirus in diarrheal stools. The latex agglutination test showed that the sensitivity was 98.2% and the specificity was 94.8%, in comparison with electron microscopy as the gold standard. Furthermore, to measure the virus concentration in stool samples, an automated latex photometric immunoassay system (LPIA) was used, which has been developed for quantitative measurement of agglutination. The range of the reactive viruses detected by the LPIA system was 3 x 10(7)-10(9) virions/mL. The rotavirus-positive and rotavirus-negative subjects were clearly discriminated. The results were in good accordance with electron microscope results. Those results showed that the latex agglutination test is a good tool for the simple and rapid detection of rotavirus in stool samples.

Animals↗
PubMed2000

Rotavirus infection among infants with diarrhea in Vietnam.

Rotavirus was examined from diarrheal stool samples of 158 infants in rural area near Ho Chi Minh City, Vietnam, from 1994 to 1996. Group A rotavirus was detected in 50%. G1 and G4 were the predominant serotypes. G3 was not detected. The most predominant type changed from year to year. Rotavirus was found in all seasons, especially in winter and autumn. Infants younger than 2 years of age were those mostly infected and the virus was suspected to invade high concentration in this area.

Diarrhea↗