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F Taguchi

Publications and source records attributed to F Taguchi.

At least 109 records · Page 6Linked to original sources

Expression of the spike protein of murine coronavirus JHM using a baculovirus vector.

The spike (S) protein of murine coronavirus JHM strain (JHMV) has been expressed in insect cells using a recombinant baculovirus vector. The expressed S protein was shown to be glycosylated and expressed on the cell surface, and to be similar in size and antigenic properties to the S protein produced in mouse cells infected by JHMV. However, no proteolytic cleavage was detected in insect cells. The sera from rats immunised with S protein derived from insect cells reacted in immunoprecipitation and immunofluorescence with the S protein produced in JHMV-infected mouse cells. However, the antisera failed to neutralize the infectivity of JHMV. The studies on two proteins expressed by recombinant baculoviruses, corresponding to the cleavage products S1 and S2, and a panel of monoclonal antibodies suggest that the majority of epitopes which elicit the neutralizing antibodies are present in the N terminal half of the S protein.

Animals↗

Regulatory DNA sequence conserved in the course of BK virus evolution.

Within the genome of human polyomavirus BK (BKV), there exists a noncoding regulatory region toward the late region side of the origin of DNA replication. In most BKV strains isolated by viral culture, this regulatory region contains tandem repeats varying in size. Recently, however, several laboratories isolated new BKV strains (designated as archetypal strains) lacking such repeat sequences. To examine the genetic relationship between archetypal strains, a phylogenetic tree was constructed for seven BKV strains, including three archetypal strains, from DNA sequence data on the late genes, those for leader protein (agnoprotein), and those for structural proteins (VP1, VP2, and VP3). For three strains data previously reported were used, whereas for the others sequences were determined in this study. From total numbers of nucleotide substitutions in each pair of strains, a phylogenetic tree was constructed by the unweighted pair-group method. The phylogenetic tree obtained reveals that BKV strains containing the archetypal regulatory region do not constitute a cluster of closely related strains and that these strains, together with those carrying the major part of the archetypal regulatory region, are widespread in the BKV population. This finding suggests that the basic structure of the archetypal regulatory region has been conserved in the course of BKV evolution.

BK Virus↗

Isolation of a possible archetypal JC virus DNA sequence from nonimmunocompromised individuals.

We molecularly cloned JC polyomavirus DNAs from urine samples of eight nonimmunosuppressed patients and two healthy individuals. The cloned viral DNAs all contained an archetypal regulatory sequence from which various regulatory sequences of JC polyomavirus isolates derived from patients with progressive multifocal leukoencephalopathy could have evolved by deletion and amplification.

Base Sequence↗

[Acute promyelocytic leukemia developed in the course of systemic lupus erythematosus: a case report].

A-36-year old Japanese female who had been suffered from systemic lupus erythematosus (SLE) and treated with prednisolone for 3.5 years developed de novo acute promyelocytic leukemia (APL) without preleukemic state. She had a short period of complete remission in leukemia but she died with recurrence of leukemia. While malignant tumors including lymphoid malignancy have been shown to develop occasionally in the course of SLE, acute myelogenous leukemia (AML) following SLE is a very rare condition. Although combination of SLE and AML may be incidental, review of the literatures revealed some interesting insight into the pathogenesis of SLE and AML.

Adult↗

Rapid identification and typing of herpes simplex virus by a new enzyme immunoassay with peroxidase-labeled complement C1q.

A new enzyme-linked immunoassay system (TC-ELISA) was developed for the rapid, specific detection and typing of herpes simplex virus (HSV) using anti-HSV immune sera and enzyme-labeled complement component C1q (P*-C1q). The method is based on viral antigen produced in HSV-infected cells being detected by simultaneous addition of immune serum and P*-C1q (ELISA-CF). With this assay, it was found that HSV was detected with anti-HSV immune serum and P*-C1q and that HSV type 1 and HSV type 2 could be differentiated with anti-HSV-1 and anti-HSV-2 immune sera and P*-C1q. The TC-ELISA test was HSV specific and not reactive with measles virus, cytomegalovirus, mumps virus or varicella-zoster virus. The whole assay procedure can be completed within 3 hours, as long as HSV-inoculated cell cultures with more than 10% cytopathic effect are used. These results suggest that TC-ELISA is useful in the diagnosis of viral infections.

Antibodies, Viral↗

Comparison of six different murine coronavirus JHM variants by monoclonal antibodies against the E2 glycoprotein.

We have examined six different JHMV variants, sp-4 (recloned wt JHMV), cl-2, CNSV, DL, DS, and JHM-X, in terms of the sizes of the mRNA3 and E2 glycoprotein as well as their reactivity to a panel of monoclonal antibodies to the E2 glycoprotein. Two of these variants, sp-4 and JHM-X, were found to have smaller mRNA3 and E2 glycoprotein species compared with those of the other four variants. In addition, sp-4 and JHM-X were distinguished from the other four variants by their inability to bind to monoclonal antibodies recognizing two antigenic domains of the E2 molecule. Thus, six JHMV variants could clearly be divided into two groups with respect to the size and antigenicity of their E2 glycoproteins.

Animals↗

Expression of the peplomer glycoprotein of murine coronavirus JHM using a baculovirus vector.

The gene encoding the E2 peplomer glycoprotein of coronavirus mouse hepatitis virus JHM strain (JHMV) has been inserted into the genome of Autographa californica nuclear polyhedrosis baculovirus (AcNPV) in lieu of the coding region of the AcNPV polyhedrin gene. This recombinant virus produced E2 protein in insect cells under the control of the baculovirus polyhedrin promotor. The expressed E2 protein was shown in size and antigenic properties to be similar to the E2 protein produced in mouse cells infected by JHMV. The expressed E2 protein was glycosylated and transported to the cell surface; however, no proteolytic cleavage was detected in insect cells. The sera from rats immunized with partially purified E2 protein derived from insect cells reacted in immunoprecipitation and immunofluorescence experiments with the E2 protein produced in JHMV-infected mouse cells. The antiserum failed to neutralize the infectivity of JHMV. These results suggest that the E2 protein expressed by the recombinant baculovirus in insect cells is similar but not identical to the E2 protein produced in JHMV-infected mouse cells. The inability of the E2 protein expressed in insect cells to produce neutralizing antibody is discussed.

Animals↗

Patterns of cardiovascular responses to stress as a function of race and parental hypertension in men.

This study investigated cardiovascular responses to two stressors known to elicit either beta-adrenergic (mental arithmetic) or alpha-adrenergic (forehead cold pressor) reactivity in Black and White men. Participants in each group were selected for presence or absence of parental hypertension. Based on previous research, Blacks were expected to show smaller cardiovascular responses to the beta-adrenergic mental arithmetic task and greater responses to the alpha-adrenergic cold pressor relative to the Whites. Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate, forearm blood flow, and forearm vascular resistance were assessed during a resting baseline, a prestress period, and during and after each experimental procedure. Unlike previous findings, no significant racial differences in cardiovascular responses were found during either task. However, Black participants had significantly higher SBP and DBP levels throughout the cold pressor periods. Parental history did not significantly influence cardiovascular responses in either group. The results are discussed in relation to previous research on racial differences in stress reactivity and their implications for future research.

Adrenergic Fibers↗

Subcellular distribution of the transmissible agent in Creutzfeldt-Jakob disease mouse brain.

To determine the intracellular localization of the Creutzfeldt-Jakob disease (CJD) agent in mouse brain, cerebrum tissue of the mouse brain affected with the Fukuoka-1 strain was separated into six subcellular fractions (microsome, nerve ending, myelin, mitochondria, nucleus, and soluble fractions) by differential sucrose density gradient, and then the CJD infectivity of these fractions was examined. Serially diluted samples of each subfraction were inoculated intracerebrally into groups of BALB/c mice, and the infectivity was determined as to end point titration value, incubation period, and number of affected mice. On the basis of the protein content, the highest CJD infectivity was observed in the microsomal fraction. The nerve ending (synaptic plasma membrane) and myelin fractions were also infective. The mitochondria and nucleus fractions showed the lower infectivity. The infectivity of the soluble fraction was the lowest among the six subcellular fractions. From the findings obtained in this study two possibilities as to the intracellular localization of CJD agent were suggested: 1) the transmissible agent of CJD is closely associated with surface membranes of neuronal and/or glial cells, including their processes; 2) the CJD agent is diffusely present intracellularly, including in the surface membranes, but for manifestation of infectivity the agent needs membrane components as prerequisite factors.

Animals↗

Race, parental history of hypertension, and patterns of cardiovascular reactivity in women.

This study examined the interaction of race and parental history of hypertension on patterns of cardiovascular responses among women. Two stressors were used that produce different patterns of cardiovascular reactivity: mental arithmetic, primarily a beta-adrenergic stimulus, and the cold face stimulus, which evokes alpha-adrenergic (i.e. vascular) activity. Systolic and diastolic blood pressure, heart rate, forearm blood flow, and forearm vascular resistance were assessed before, during, and after arithmetic and cold face stimulus. Both tasks produced the expected patterns of cardiovascular adjustment, although no Black-White differences occurred during arithmetic. However, Black subjects did show a slower recovery of diastolic blood pressure following arithmetic. The cold face stimulus produced significantly greater changes in systolic blood pressure in the Black than in the White women. Parental history of hypertension did not relate significantly to reactivity. The results provide limited support for the idea that Black females exhibit a greater pressor response than White females to a stimulus that produces primarily vascular rather than cardiac changes. These findings are discussed in relation to previous findings with males and with respect to their implications for the role of reactivity in Black-White differences in hypertension prevalence.

Adolescent↗

Growth efficiency of naturally occurring BK virus variants in vivo and in vitro.

We molecularly cloned a number of BK virus (BKV) DNAs from urine samples collected from a patient with systemic lupus erythematosus undergoing immunosuppressive therapy. On the basis of the structure of the noncoding regulatory region, cloned viral DNAs were classified into a major group and several minor groups. The major group contained a single 68-base-pair (bp) promoter-enhancer element and a 63-bp sequence identified in the genomes of many BKV strains. Most of the minor groups retained a variety of duplications within the transcriptional control region and the origin of DNA replication. We assayed various cloned viral DNAs for the capacity to induce viral growth in transfected human embryonic kidney cells. While major viral DNAs induced slow viral replication, a minor viral DNA retaining partial duplication of the 68-bp element induced rapid viral growth. We concluded that reiteration of the promoter-enhancer element, which is required for efficient growth of BKV in cell culture, is not advantageous for replication of BKV in natural hosts.

BK Virus↗

Beta and alpha adrenergic reactivity elicitable stress study with special reference of electrocardiographic T-wave amplitude.

Twenty-six healthy young Caucasian males were defined into high hostile (Hi-Ho) group and low hostile (Lo-Ho) group assessed by Cook-Madley's Hostility (Ho) scale. Mental arithmetic task (MA) and forehead cold stimulus task (FCS) were loaded to both Hi-Ho and Lo-Ho groups. Electrocardiographic T-wave amplitude (TWA), heart rate (HR) and coefficient of variance of 100 R-R intervals (CVR-R) were measured continuously during MA and FCS task periods. Greater TWA attenuation was found in Hi-Ho group (p less than 0.05). Although no significant intergroup difference was represented in HR and CVR-R, HR increased significantly (p less than 0.01) in whole subjects and CVR-R was tend to be suppressed during MA period. In addition, comparison of these physiological responses were performed between Type-A and Type-B groups classified by Jenkins' Activity Survey Form-T (JAS-T). There was no significant difference in reactivity of TWA, HR and CVR-R to both two tasks between high and low Type-A scored groups. Previous data suggested that the TWA reactivity in Hi-Ho subjects to cognitive stress showed similar pattern in Type-A individuals. However, autonomic nervous interaction could not be clarified in Hi-Ho subjects. The differentiation of method for assessment of behavioral pattern was also discussed.

Adolescent↗

[Rapid bone marrow dissemination of gastrointestinal lymphomas after surgical resection].

We describe two cases of gastrointestinal lymphoma associated with rapid bone marrow dissemination after surgical resection. Case 1: A 73-year-old male was diagnosed as having malignant lymphoma originating from ileocaecal region (diffuse medium-sized, B cell type). Tumor (8 x 8 cm) was resected but infiltrated to the peritoneum and curative operation could not be done. Two weeks after operation, elevation of LDH, pancytopenia and bone marrow infiltration of lymphoma cells developed and he died of respiratory failure. Case 2: A 69-year-old female was diagnosed as having remnant gastric lymphoma (diffuse large, B cell type). Tumor size was 5 x 4 cm and swelling of the third lymph nodes was found, so curative operation could not be done. Two months after operation bone marrow infiltration of lymphoma cells was observed and she is now undergoing chemotherapy. Surgical resection is performed in the majority of patients with localized gastrointestinal lymphoma. But the operation of the advanced case must be carefully done, because the operative procedure may sometimes facilitate growth and metastasis of tumor.

Aged↗

New complement fixation test with peroxidase-labeled complement Clq for direct and quantitative determination of antibodies to herpes simplex virus.

An enzyme-labeled complement fixation (ELISA-CF) test for the direct and quantitative determination of complement fixing (CF) antibodies has been developed. This paper described the introduction of the ELISA-CF test that used peroxidase-labeled Clq component of complement to detect CF antibodies which had reacted with herpes simplex virus (HSV), as a virus model. Equal volumes of heat-inactivated serum and the peroxidase-labeled Clq (P*-Clq) were simultaneously added to wells of microplates which had been coated with HSV CF antigen or with cell control antigen. The enzymatic activities of P*-Clq bound to the immune complex were determined photometrically. The ELISA-CF test allows processing of serum specimens in a 3-hr operation, with procedural simplicity and increased specificity and sensitivity compared with the conventional CF test.

Antibodies, Viral↗

Variation of R1 repeated sequence present in open reading frame 11 of varicella-zoster virus strains.

We molecularly cloned the tandem direct reiteration (R1) present in open reading frame (ORF) 11 from three independent strains of varicella-zoster virus. Comparison of the R1 sequences among varicella-zoster virus strains revealed that, although the portion of R1 near the 5' terminus of ORF 11 was conserved among strains, the 3'-terminal portion varied remarkably. This variation was due to the different arrangement of two elements (A and B) and a segment produced by fusion of A and B and to a single-base change in the A element. Since the difference in the size of R1 among strains was a multiple of 3 base pairs, the variation in R1 caused no frame shift in ORF 11.

DNA, Recombinant↗