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Biomedical subjects

T Mimori

Publications and source records attributed to T Mimori.

At least 145 records · Page 8Linked to original sources
PubMed1987

The relationship between severity of ulcerated lesions and immune responses in the early stage of cutaneous leishmaniasis in Ecuador.

The relationship was examined between the severity of ulcerated lesions and immune responses in 19 Ecuadorian patients in the early stages of New World cutaneous leishmaniasis. As an immunological assay, the humoral immune response was assessed by enzyme-linked immunosorbent assay (ELISA) and the cell-mediated response by delayed type skin test for leishmanial antigen (leishmanin test). There was a statistically significant correlation (r = 0.61, P less than 0.01) between the total area of ulcerated lesions and the reciprocal titre of ELISA in identical subjects. However, no significant difference was observed in the ELISA titre between patients with a single lesion and those with multiple lesions (chi 2 = 7.06, df = 5, P greater than 0.2). A correlation (r = 0.48, P less than 0.05) was observed between the area of lesions and the intensity of leishmanin test; further, the ELISA titre also correlated to the intensity of leishmanin test in the identical subjects (r = 0.71, P less than 0.01). These results suggest that the severity of ulcerated lesions relates to the activation of both the humoral and cell-mediated immune systems in the early stage of New World cutaneous leishmaniasis.

Adolescent↗
PubMed1987

Autoantibodies to the Sm antigen: immunological approach to clinical aspects of systemic lupus erythematosus.

The precise antigenic peptide of Sm antigen (U small nuclear ribonucleoproteins, U snRNP) and the clinical significance of anti-Sm antibodies in systemic lupus erythematosus (SLE) detected by a sensitive radioimmunoassay were studied. By immunoblotting, anti-Sm sera reacted with B'/B peptides of U1 snRNP and D peptide of U1-U2 snRNP, while anti-U1 RNP recognized 68k, A, B'/B and C peptides. Reblotting study using the specific antibodies against each peptide eluted from the blot sheets demonstrated that B'/B and D peptides shared a common Sm antigenic epitope. We purified D peptide from U1 snRNP and established a radioimmunoassay. Anti-Sm antibodies were found in 30% of the patients with SLE using this method, which was more sensitive than the conventional assays. Anti-Sm was associated with late onset renal disease and poor prognosis when analyzed with Cox's regression model.

Autoantibodies↗
PubMed1987

A study on immunodiagnosis of gnathostomiasis by ELISA and double diffusion with special reference to the antigenicity of Gnathostoma doloresi.

In order to diagnose gnathostomiasis immunologically, Gnathostoma doloresi was evaluated for the antigenicity in comparison with G. hispidum which was recently reported in Japan by using micro-ELISA. The study revealed that G. doloresi can be used as the alternate source of antigen in the test. A significant increase of specific IgG antibodies was seen in 22 (73.3%) out of 30 gnathostomiasis cases. Although double diffusion was slightly less sensitive than ELISA, it was considered more specific than the latter method.

Animals↗
PubMed1986

Mechanism of interaction between Ku protein and DNA.

The mechanism of interaction between the Ku autoantigenic protein, a heterodimer of noncovalently linked 70,000- and 80,000-dalton subunits, and DNA was studied using immunoaffinity-purified Ku protein and a 300-base pair EcoRI fragment from HeLa cell DNA. In the nitrocellulose filter-binding assay, the Ku protein bound 32P-labeled double-stranded DNA, and much less efficiently single-stranded DNA. The binding of Ku to DNA was dependent on ionic strength and prevented by IgG from patient sera containing anti-Ku antibodies. In competitive assays, using unlabeled nucleic acid competitors, the DNA binding of Ku was not inhibited in the presence of yeast tRNA, synthetic copolymer of poly(A)-poly(dT), or circular plasmid pBR322 DNA, but was inhibited when the plasmid DNA was cleaved with appropriate restriction endonucleases. The inhibitory activities of cleaved plasmid DNA were independent of the configuration or nucleotide sequences at ends but proportional to the number of recognition sites of restriction enzymes used. Footprint analysis demonstrated that Ku protein protected both 3'- and 5'-terminal regions of double-stranded DNA from DNase I digestion. When Ku protein was fractionated electrophoretically, transferred to nitrocellulose filter, and probed with 32P-labeled DNA, only the 70,000-dalton subunit exhibited DNA binding. Thus, the Ku protein appears to recognize selectively ends of double-stranded DNA molecules. Possible functions of the Ku autoantigen in eukaryotic cells are discussed.

Antigens, Nuclear↗
PubMed1986

Characterization of the DNA-binding protein antigen Ku recognized by autoantibodies from patients with rheumatic disorders.

We have characterized the biochemical nature of the Ku protein, the antigen recognized by autoantibodies from certain patients with scleroderma-polymyositis overlap syndrome. From extracts of HeLa cells labeled with [32P]orthophosphate, anti-Ku antibodies precipitated a high molecular weight nucleic acid identified as DNA because of sensitivity to DNase I and resistance to RNase. From extracts of cells labeled with [35S] methionine, these antibodies precipitated two polypeptides of 70,000 and 80,000 Da. These proteins were purified using immunoaffinity column chromatography. In immunoblots most sera containing anti-Ku antibodies recognized both Ku proteins but one serum bound only to the 70,000-Da subunit. When nucleosomal segments of chromatin were used as antigen, anti-Ku antibodies precipitated dinucleosomes and larger forms of chromatin but not mononucleosomes. Thus, the Ku antigen is a novel DNA-binding protein that is at least partially exposed on nucleosomal segments of chromatin.

Antigens, Nuclear↗
PubMed1986

Dirofilaria infection in the breast of a woman in Japan.

Dirofilaria infection in the breast of a woman was reported from Japan. A nodule in the breast was excised and histologically examined. The sections of a female nematode were found in the center of the nodule. Based on the morphological features of this worm, it is suggested that this may represent the second human case of Dirofilaria immitis occurring in the breast.

Adult↗
PubMed1985

Detection of antibodies to small nuclear ribonucleoproteins and small cytoplasmic ribonucleoproteins using unlabeled cell extracts.

RNA molecules immunoprecipitated with sera from patients who have rheumatic diseases can be readily detected in polyacrylamide gels by using ethidium bromide and silver stains. With these stains, we found that RNA patterns characteristic of a broad range of specific small nuclear ribonucleoproteins and small cytoplasmic ribonucleoproteins were recognizable. The stains correctly identified antibodies to ribonucleoproteins in 33 (92%) of 36 patient sera selected for study because of known antibody specificities. The silver stain method detected antibodies to ribonucleoproteins in 25 (76%) of 33 patients with classic systemic lupus erythematosus, a frequency that approximated the frequency observed in the Lerner-Steitz assay, which is based on autoradiography. This approach considerably simplifies the latter radioimmunoassay with minimal loss of precision and sensitivity.

Autoantibodies↗
PubMed1985

Biting activity of two anthropophilic species of sandflies, Lutzomyia, in an endemic area of leishmaniasis in Ecuador.

The biting patterns of Lutzomyia trapidoi and Lu. hartmanni, vectors of leishmaniasis, were studied using a human bait in an endemic area on the Pacific slope of the Andes in Ecuador. The results suggest that Lu. trapidoi is primarily an early biter at dusk, with the first peak at 20.00-21.00 hours and the second at 03.00-04.00 hours; and that Lu. hartmanni bites more constantly throughout the night, with a pronounced peak between 23.00 and 24.00 hours. The biting activity, however, shows a marked variation at each site and between different collections at the same site. The activity and the biting places on man are discussed in relation to human infection with leishmaniasis in the area and the location of lesions on patients.

Animals↗
PubMed1985

Natural infections with promastigotes in man-biting species of sand flies in leishmaniasis-endemic areas of Ecuador.

In order to determine the vectors of leishmaniasis in Ecuador, 1,054 man biting sand flies from the Department of Cañar were dissected and examined for promastigotes. There were 2 man-biting species, Lu. trapidoi and Lu. hartmanni in this endemic area of the disease. The infection rates were 7.7% in the former and 3.9% in the latter species, demonstrating the different rates in various localities and altitudes of the study areas. There was an association between infection rates and the time of day, suggesting some connection with biting activity of sand fly species. In collections using human bait at 7 study areas in 5 Departments, 6 man-biting species were recognized, indicating different dominant species in each area. It was assumed that the dominant species would play an important role as the principal vector of leishmaniasis in each endemic area. As to species determination of the present Leishmania promastigotes, suffice it to say that the parasites are Leishmania sp., presumably L. braziliensis s.l., until the isolates have been typed.

Animals↗
PubMed1985

Autoantibodies to ribonucleoproteins.

Presently we recognize at least 12 different autoantibodies that involve ribonucleoproteins as antigens in patients with SLE and other rheumatic diseases. Such autoantibodies have a number of clinically useful diagnostic associations. Moreover, they have proved to be powerful tools for understanding the structure and function of a variety of cellular components that involve RNA molecules. In SLE, autoantibodies that recognize the U1 snRNP (i.e. anti-(U1)RNP and anti-Sm antibodies) and the Ro scRNPs (i.e. anti-Ro and anti-La antibodies) are especially prominent in terms of their high frequency and titre. These particles, along with the nucleosome (which is the principal focus of autoantibodies to chromatin) appear to have active roles in eliciting autoimmune responses in such patients. Future studies aimed at understanding how and when these particular structures interact with the immune system could provide important insights into the aetiology and pathogenesis of this disorder.

Antibodies, Antinuclear↗
PubMed1984

The structure of mammalian small nuclear ribonucleoproteins. Identification of multiple protein components reactive with anti-(U1)ribonucleoprotein and anti-Sm autoantibodies.

The Sm small nuclear ribonucleoproteins (snRNPs) from mammalian cells have been characterized as containing U1, U2, U4, U5, and U6 RNA associated with some subset of at least 10 distinct polypeptides (called 68K, A, A', B, B', C, D, E, F, and G) that range in molecular weight from 68,000 to 11,000. Whereas this entire collection of snRNP particles is precipitated by patient anti-Sm autoantibodies, anti-(U1)RNP autoantibodies specifically recognize U1 snRNPs. Here, we have performed immunoblots using the sera from 29 patients and a mouse anti-Sm monoclonal antibody to identify which HeLa cell snRNP proteins carry anti-Sm or anti-(U1)RNP antigenic determinants. Strikingly, every serum surveyed, as well as the monoclonal antibody, recognizes determinants on two or more snRNP protein components. The three proteins, 68K, A, and C, that uniquely fractionate with U1 snRNPs are specifically reactive with anti-(U1)RNP sera in blots. Anti-Sm patient sera and the mouse monoclonal antibody react with proteins B, B', D, and sometimes E, one or more of which must be present on all Sm snRNPs. The blot results combined with data obtained from a refined 32P-labeled RNA immunoprecipitation assay reveal that, in our collection of the sera from 29 patients, anti-Sm rarely exists in the absence of equal or higher titers of anti-(U1)RNP; moreover, (U1)RNP sera often contain detectable levels of anti-Sm. Our findings further define the protein composition of the Sm snRNPs and raise intriguing questions concerning the relatedness of snRNP polypeptides and the mechanism of autoantibody induction.

Animals↗
PubMed1984

Autoantibodies to the U2 small nuclear ribonucleoprotein in a patient with scleroderma-polymyositis overlap syndrome.

Autoantibodies directed against the U2 small nuclear ribonucleoprotein (snRNP) have been found in the serum of a patient with scleroderma-polymyositis overlap syndrome. This specificity, called anti-(U2)-RNP, is distinct from all previously described autoantibodies, including those that precipitate related snRNPs: anti-Sm antibodies, which react with the entire set of U1, U2, U4, U5, and U6 snRNPs, and anti-(U1)RNP antibodies, which recognize only U1 snRNPs. From HeLa cell extracts, anti-(U2)RNP immunoprecipitates predominantly one 32P-labeled RNA species, identified as U2 small nuclear RNA, and six [35S]methionine-labeled protein bands, A' (Mr = 32,000), B (Mr = 28,000), D (Mr = 16,000), E (Mr = 13,000), F (Mr = 12,000), and G (Mr = 11,000). Protein blot analysis reveals that the A' protein carries (U2)RNP antigenic determinant(s) and therefore represents a polypeptide unique to the U2 snRNP; the B protein associated with U2 snRNPs may also be unique. Like U1 and the other Sm snRNPs, U2 snRNPs occupy a nuclear, non-nucleolar location and are antigenically conserved from insects to man. An antibody specific for the U2 snRNP will be useful in deciphering the function of this particle.

Autoantibodies↗
PubMed1983

The precipitating antibody to an acidic nuclear protein antigen, the Jo-1, in connective tissue diseases. A marker for a subset of polymyositis with interstitial pulmonary fibrosis.

The clinical significance of antibodies to the Jo-1 antigen in connective tissue diseases was studied. Clinical diagnoses of 11 patients who had anti-Jo-1 antibody were: polymyositis 8, dermatomyositis 1, and overlap syndrome 2 (polymyositis--systemic lupus erythematosus 1, polymyositis--scleroderma 1). All the patients who had anti-Jo-1 antibody showed interstitial pulmonary fibrosis, and in 2 patients anti-Jo-1 antibodies were detected before the appearance of lung disease.

Adult↗
PubMed1983

Strongyloides ratti: the role of enteral antigenic stimuli by adult worms in the generation of protective immunity in rats.

Immunogenicity of adult Strongyloides ratti was studied in rats. Immunization of rats by intraduodenal implantation of adult worms could completely inhibit the egg production and hasten the expulsion of challenged worms which were developed from subcutaneously inoculated L3 or were implanted intraduodenally as adults. Enteral immunization by intraduodenal implantation of adult worms was, however, not able to affect the esophageal larval output of the challenge infection with L3. In contrast to enteral immunization with adult worms, immunization by full sequence of a primary infection or by a combination of drug-abbreviated infection and adult worm implantation could suppress the esophageal larval output of the challenge infection. The relationship between the host defense mechanism and the life cycle of S. ratti is discussed.

Animals↗