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Biomedical subjects

N Amino

Publications and source records attributed to N Amino.

At least 37 records · Page 2Linked to original sources

Heterologous enzyme immunoassay for serum androstenediol.

A heterologous enzyme immunoassay for serum androstenediol (Adiol: 3beta, 17beta-dihydroxy-androst-5-ene) was established. The combination of anti-Adiol antiserum raised in rabbit against Adiol 7-O-(carboxymethyl)oxime (Adiol 7-CMO) conjugated bovine serum albumin (Adiol 7-CMO-BSA) and Adiol 7-iminomethylcarboxylic acid conjugated alkaline phosphatase was used for the assay. The sensitivity of the heterologous assay system was superior to that of a homologous assay system in which an antibody raised in rabbit against Adiol 7-CMO-BSA and enzyme labeled antigen, Adiol 7-CMO conjugated alkaline phosphatase, were used. The minimal amount of Adiol detected was 0.4 ngml(-1) and the measurable range was from 0. 4 to 150 ngml(-1). Intra-assay coefficients of variation (C.V.) were 8.6% (1.52+/-0.13 ngml(-1), mean+/-S.D., n=10) and 6.7% (13.4+/-0.9 ngml(-1), n=10). Inter-assay C.V. were 12.9% (1.63+/-0.21 ngml(-1), n=8) and 11.5% (12.2+/-1.4 ngml(-1), n=8). A linear relation was observed between the serum sample dilution and the Adiol concentration. For recovery study, authentic Adiol was added to serum sample (original concentration: 1.43 ngml(-1)). The calculated final Adiol concentration was 2.99 ngml(-1). The recovery was 98.6% (n=5). The Adiol concentrations in healthy subjects measured by the proposed assay (male: 1.1+/-0.3 ngml(-1) (mean+/-S.D.), range: 0.7-1. 7 ngml(-1), age: 22-50, n=10; female: 0.6+/-0.4 ngml(-1), range: 0. 2-1.6 ngml(-1), age: 23-48, n=20) were consistent with reported values.

Adult↗

Enzyme-linked immunosorbent assay for anti-tropomyosin antibodies and its clinical application to various heart diseases.

Tropomyosin is one of the key proteins for muscle contraction. We developed an enzyme-linked immunosorbent assay for antibodies to porcine muscle tropomyosin and measured serum anti-tropomyosin antibodies in patients with heart diseases and in normal controls. The mean values of absorbance in the ELISA assay of patients with ischemic heart disease (n=36, P<0.001), dilated cardiomyopathy (n=28, P<0.005), valvular heart disease (n=27, P<0.05), and collagen disease (n=38, P<0.05) were significantly higher than those of normal controls (n=53), but the value in patients with hypertrophic cardiomyopathy (n=19) was not significantly different from that of normal controls. When the cut-off value was fixed at the mean+2 SD of absorbance in normal controls, positive reactions were found in 19.4%, 7.1%, 18.5% and 15.8% of patients with ischemic heart disease, dilated cardiomyopathy, valvular heart disease, and collagen disease, respectively. An inhibition study revealed that anti-tropomyosin antibodies were different from anti-myosin antibodies, but there was a partial cross-reactivity between the two. Thus, there was a weak correlation of the titers of the two types of antibody within the group of heart diseases. These data indicate that measurement of anti-tropomyosin antibodies by ELISA is helpful for detecting autoimmune abnormalities in various heart diseases.

Adult↗

Gene expression profiles in thyroid carcinomas.

The gene expression profiles of human thyroid carcinomas were analysed by serial analysis of gene expression (SAGE) which allows quantitative and simultaneous analysis of a large number of transcripts. More than 29,000 transcripts derived from a normal thyroid tissue and four thyroid tumours were analysed. While extensive similarity was noted between the expression profiles of the normal thyroid tissue and three differentiated thyroid tumours, many transcripts, such as osteonectin, a-tubulin, glyceraldehyde-3-phosphate dehydrogenase, glutathione peroxidase, and thyroglobulin, were expressed at extremely different levels in differentiated and undifferentiated carcinomas. These data provide new information that might be used to identify genes useful for the diagnosis and treatment of thyroid carcinomas.

Adenoma↗

A novel V59E missense mutation in the sodium iodide symporter gene in a family with iodide transport defect.

Iodide transport defect results from the malfunction of iodide transporter (sodium iodide symporter [NIS]), and is characterized by low uptake of iodide into thyroid cells. Genetic analysis revealed that a T354P missense mutation causes iodide transport defect in the homozygous state and is a frequent mutation in the Japanese population. We recently reported three siblings with iodide transport defect harboring the T354P mutation in the heterozygous state. Here we report a novel V59E missense mutation associated with these siblings. The mutant protein showed low iodide transport activity.

Adult↗

Changes in cytokine production during and after normal pregnancy.

PROBLEM: The systemic T helper 1/T helper 2 (Th1/Th2) cytokine balance during normal human pregnancy is controversial, and observations about the balance in the postpartum period have only been reported for up to 3 months. METHOD: Whole-blood, from 83 healthy pregnant women, 80 healthy postpartum women, and 31 healthy non-pregnant women was stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin, and the levels of cytokines in the supernatant were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The production of all measured cytokines decreased during pregnancy, especially in the second trimester. After delivery, interferon-gamma (IFN-gamma) and interleukin-2 (IL-2) increased from 2 to 11 months postpartum, and IL-4 increased from 6 to 11 months postpartum. CONCLUSIONS: These data indicate that 1) decreases in production of both Th1-and Th2-type cytokines during pregnancy may be related to the pregnancy-induced amelioration of autoimmune diseases: 2) increases in production of both Th1- and Th2-type cytokines in the postpartum period may be related to the postpartum aggravation of autoimmune diseases.

Adult↗

Expression of oncofetal fibronectin messenger ribonucleic acid in fibroblasts in the thyroid: a possible cause of false positive results in molecular-based diagnosis of thyroid carcinomas.

Oncofetal fibronectin (onfFN) messenger ribonucleic acid (mRNA) is abundantly expressed in thyroid papillary and anaplastic carcinomas. These carcinomas can be preoperatively diagnosed by the detection of onfFN mRNA in fine needle aspiration biopsies (FNABs). However, previous reports have noted that the expression of onfFN mRNA was observed in 3.7% of the FNABs that were diagnosed as negative cytology. To clarify this discrepancy, we examined the expression of onfFN mRNA in fibroblasts in the thyroid. By RT-PCR and real-time quantitative RT-PCR analyses, we detected a high copy number of onfFN mRNA in cultured fibroblasts obtained from the normal thyroid tissues dissected surgically. Thus, we conclude that the contaminated fibroblasts in FNABs due to tumor necrosis or acute or chronic inflammation may be a cause of false positive results in molecular-based diagnosis of thyroid carcinomas.

Carcinoma↗

Diagnosis of thyroid malignant lymphoma by reverse transcription-polymerase chain reaction detecting the monoclonality of immunoglobulin heavy chain messenger ribonucleic acid.

Distinguishing between thyroid malignant lymphoma and lymphocytic thyroiditis (Hashimoto's thyroiditis) is quite difficult and problematic. Molecular techniques to detect clonal lymphoid proliferation based on Ig heavy chain (IgH) gene rearrangement may be used to facilitate more accurate diagnosis of malignant lymphoma. We recently established a method for diagnosing thyroid tumors by analyzing ribonucleic acids (RNAs) extracted from the needles used for fine needle aspiration biopsy (aspiration biopsy-RT-PCR). By applying the aspiration biopsy-RT-PCR method to detection of the monoclonality of IgH messenger RNA (mRNA), an accurate molecular-based diagnosis of malignant lymphoma can be established as an adjunct to cytological diagnosis. We first studied RNAs from fresh tissues samples of 8 cases of Hashimoto's thyroiditis and 18 malignant lymphomas to detect the monoclonality of IgH mRNA by seminested RT-PCR. Monoclonality was detected in 8 of 18 (44.4%) malignant lymphomas, but in none of the 8 cases of Hashimoto's thyroiditis. We then studied aspirates from 10 cases of thyroid malignant lymphoma, 4 cases of Hashimoto's thyroiditis, and 1 case each of adenomatous goiter and papillary carcinoma. Monoclonality was detected in the aspirates from 4 of 10 malignant lymphomas (40%), but not from other tissues. Thus, RT-PCR detection of monoclonality of IgH mRNA in addition to cytological examination may be useful in diagnosing thyroid malignant lymphoma.

Adenoma↗

Preoperative diagnosis of thyroid carcinomas by aspiration biopsy-reverse transcription-polymerase chain reaction (ABRP): a report of two cases.

A preoperative molecular-based diagnostic technique for thyroid papillary and anaplastic carcinomas was recently developed to detect oncofetal fibronectin (onfFN) messenger RNA (mRNA) in fine needle aspiration biopsy (FNAB) by means of reverse transcription-polymerase chain reaction (RT-PCR). We report two cases of thyroid tumors, in which cytological diagnosis was not successful but in which RT-PCR analysis provided information that helped to identify the biological features of the tumors. One case could not be diagnosed by aspiration biopsy cytology (ABC) because of poor fixation; however, RT-PCR did detect the expression of onfFN mRNA, which suggested the existence of papillary carcinoma cells. After surgery, this tumor was diagnosed as a papillary carcinoma by histological examination. The other case was diagnosed as a papillary carcinoma by ABC, but onfFN mRNA was not detected in the FNAB by RT-PCR. The neoplasm was diagnosed as a follicular tumor by histological examination. These cases suggest the benefits of combining both genetic and cytological approaches to the examination of FNAB.

Adult↗

Self-examination of thyroid nodules.

The management of occult small thyroid nodules found by ultrasonography is sometimes problematic. Self-palpation may be utilized in the follow-up of these nodules. We developed a method of thyroid self-examination (TSE). We examined the size of the nodules palpable by this method by ultrasonography. In 78 patients examined, all 38 tumors more than 2 cm in size, whereas only one of 14 tumors less than or equal to 1 cm in size, were palpable. These results suggest the clinical usefulness of TSE in the follow-up of thyroid tumors, which are very common and slow-growing.

Adolescent↗

A novel mutation of the KAL1 gene in monozygotic twins with Kallmann syndrome.

OBJECTIVE: Kallmann syndrome is defined by the association of hypogonadotropic hypogonadism and anosmia. The KAL1 gene is responsible for the X-linked form of Kallmann syndrome. In this study we describe monozygotic twins with Kallmann syndrome due to the same mutation in the KAL1 gene. DESIGN: We studied male monozygotic twins with Kallmann syndrome. METHODS: We analyzed the KAL1 gene using the PCR-direct sequencing method. The twins' mother was examined for the identified mutation. RESULTS: We identified a 14 bp deletion from codon 419 in exon 9 (Pro419del14) in both KAL1 genes of the twins. This was a novel mutation in the KAL1 gene and was responsible for Kallmann syndrome. As Pro419del14 was not detected in the mother of the twins, Pro419del14 was a germline mutation originating from them. These monozygotic twins showed different LH and FSH responses to LH-RH stimulation and different phenotypes such as complications, physiques and psychiatric characters. CONCLUSIONS: We report an identical KAL1 gene mutation in the monozygotic twins with Kallmann syndrome. As these monozygotic twins showed different phenotypes in some respects, we suggest that factors other than mutations in the KAL1gene affect the symptomatic features of Kallmann syndrome.

Adult↗

Enzyme immunoassay for autoantibodies to human liver-type arginase and its clinical application.

BACKGROUND: Arginase is an enzyme of the urea cycle, and one of the two isoenzymes is the liver-type enzyme. We examined serum autoantibodies to this liver-type enzyme in patients with hepatitis. METHODS: Antibodies to recombinant human liver-type arginase were measured by ELISA in 95 patients and 55 healthy controls. RESULTS: The mean absorbance values in the ELISA assays of patients with definite autoimmune hepatitis (n = 11; P <0.0001), probable autoimmune hepatitis (n = 31; P <0.0001), and hepatitis C (HCV; n = 20; P <0.01) were significantly different from those of healthy controls, but the values in patients with hepatitis B (HBV; n = 23) and other autoimmune diseases (n = 10) were not significantly different from those of healthy controls. When the cutoff was fixed at the upper 95th percentile of the absorbance value in healthy controls, positive reactions were found in 18.2%, 32.3%, 20.0%, 13. 0%, and 10.0% of patients with definite autoimmune hepatitis, probable autoimmune hepatitis, HCV hepatitis, HBV hepatitis, and other autoimmune diseases, respectively. All of these positive reactions were abolished by inhibition of serum with recombinant antigen. The specificity and sensitivity of this ELISA were 96% and 29%, respectively. The intraassay and interassay coefficients of variation were 2.3-7.5% and 9.8-11%, respectively. There was no relationship between these antibodies and anti-nuclear, anti-smooth muscle, or anti-cytochrome P450IID6 antibodies. CONCLUSIONS: The ELISA for anti-liver-type arginase autoantibody improved the detectability of autoimmune hepatitis when compared with established assays for liver-specific autoantibodies.

Arginase↗

Serum dehydroepiandrosterone, dehydroepiandrosterone sulfate, and pregnenolone sulfate concentrations in patients with hyperthyroidism and hypothyroidism.

BACKGROUND: Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) have been suggested to have protective effects against cardiovascular disease, cancer, immune-modulated diseases, and aging. We examined serum concentrations of DHEA, DHEA-S, and pregnenolone sulfate (PREG-S) in patients with thyroid dysfunction. METHODS: Steroids extracted with methanol from serum sample were separated into an unconjugated fraction (DHEA) and a monosulfate fraction (DHEA-S and PREG-S), using a solid-phase extraction and an ion-exchange column. After separation of unconjugated steroids by HPLC, the DHEA concentration was measured by enzyme immunoassay. The monosulfate fraction was treated with arylsulfatase, and the freed steroids were separated by HPLC. The DHEA and PREG fractions were determined by gas chromatography-mass spectrometry, and the concentrations were converted into those of DHEA-S and PREG-S. RESULTS: Serum concentrations of DHEA, DHEA-S, and PREG-S were all significantly lower in patients with hypothyroidism (n = 24) than in age- and sex-matched healthy controls (n = 43). By contrast, in patients with hyperthyroidism (n = 22), serum DHEA-S and PREG-S concentrations were significantly higher, but the serum DHEA concentration was within the reference interval. Serum concentrations of these three steroids correlated with serum concentrations of thyroid hormones in these patients. Serum albumin and sex hormone-binding globulin concentrations were not related to these changes in the concentration of steroids. CONCLUSIONS: Serum concentrations of DHEA, DHEA-S, and PREG-S were decreased in hypothyroidism, whereas serum DHEA-S and PREG-S concentrations were increased but DHEA was normal in hyperthyroidism. Thyroid hormone may stimulate the synthesis of these steroids, and DHEA sulfotransferase might be increased in hyperthyroidism.

Adult↗

[Molecular-based diagnosis of thyroid carcinomas by detecting cancer-specific mRNAs].

Molecular-based diagnosis of thyroid carcinomas can be more easily established by utilizing specific mRNAs that are restrictedly expressed in cancer tissues. In light of this aspect, we searched for cancer-specific mRNAs using sequence specific-differential display(SS-DD) and serial analysis of gene expression(SAGE). By these techniques, we found several mRNAs that efficiently distinguished benign and malignant tissues. Among these, oncofetal fibronectin(onfFN) mRNA was expressed only in thyroid papillary and anaplastic carcinomas and it was considered the most preferable target for molecular-based diagnosis of these carcinomas. In a previous study, we introduced a new method of preoperative diagnosing thyroid carcinomas. This technique, aspiration biopsy-RT-PCR(ABRP), allows us to simultaneously perform cytological and molecular-based diagnoses by extracting RNA from leftover cells within the needle used for fine needle aspiration biopsies(FNABs). ABRP provides both RNA information and cytological diagnosis without further invasion to the patient. We demonstrated that by ABRP detection of onfFN mRNA in FNABs, papillary and anaplastic carcinomas may be accurately diagnosed preoperatively. Further, by real-time monitoring RT-PCR measurement of onfFN mRNA, a fully automated system was established.

Humans↗

[Endocrine diseases and aging].

Age dependent perturbations to endocrine systems are overviewed and the interpretation of the results of endocrinological tests for clinical decision are discussed referring to thyroid diseases as an example. The endocrine functions that are essential to life, such as adrenal and thyroid functions, show minimal change by aging. Their basal levels alter little, although production and degradation of hormones decrease. Some part of elderly persons show lower levels of triiodothyronine, which may, however, reflect deterioration of their physical condition and should not be overlooked as an age dependent change. Some endocrine function, such as gonadal function and calcium metabolism obviously reveal age dependent physiological change and their reference ranges for elderly persons are set separately. Thus, reference levels and clinical decision for endocrinological tests should be dependent on the properties of individual endocrine system.

Adult↗

[Defense mechanism and immunity].

Monocyte/macrophage (m phi) or mononuclear phagocytic system(MPS) play one of the key roles in defense mechanisms in human as well as animals. Informations as to their biological functions and significance in defense mechanisms or immune systems have increased. However, some of the details are still unknown and/or controversial. Prof. Takahashi lectured on some new findings: development of m phi precedes that of monocyte, factors regulating differentiation of m phi, differences between tissue m phi and monocyte/m phi and so on. He also stressed the complexity of the development and differentiation of monocyte/m phi. Prof Yamamoto lectured on a new factor, S19 ribosomal protein, which enhances migration of monocytes and connects natural immunity and acquired immunity. Following these lectures, all participants realized the complexity and also the mystery of defense mechanisms of our bodies.

Animals↗