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Biomedical subjects

A Miyauchi

Publications and source records attributed to A Miyauchi.

At least 73 records · Page 4Linked to original sources
PubMed1999

Preoperative diagnosis of thyroid papillary and anaplastic carcinomas by real-time quantitative reverse transcription-polymerase chain reaction of oncofetal fibronectin messenger RNA.

The restricted expression of oncofetal fibronectin (onfFN) mRNA in thyroid papillary and anaplastic carcinomas was recently reported. In this study, we measured the copy number of onfFN mRNA in RNAs extracted from fine needle aspiration biopsies by real-time quantitative reverse transcription-PCR using thyroglobulin mRNA as an internal control. By measuring the onfFN:thyroglobulin mRNA ratio, preoperative aspirates from 31 papillary carcinomas and an anaplastic carcinoma can be distinguished from those from 5 adenomatous goiters, 5 follicular adenomas, and 4 follicular carcinomas. Thus, quantification of onfFN by real-time quantitative reverse transcription-PCR may be useful for the preoperative diagnosis of papillary and anaplastic carcinomas.

Base Sequence↗
PubMed1999

Successful autotransplantation of an adrenal gland using a new method of omental wrapping: report of a case.

Bilateral total adrenalectomy results in the need for patients to take lifelong supplements of adrenal steroids, with the risk of possible Addisonian crisis. Few reports of the successful autotransplantation of adrenal tissue in muscular pockets have been documented; however, we describe herein the case of a 22-year-old woman in whom autotransplantation of an adrenal gland was successfully performed employing a new method of omental wrapping. The patient underwent bilateral total adrenalectomy for bilateral pheochromocytoma at which time adrenal tissue was sliced into 1-2-mm thick pieces, half of which were placed in muscular pockets in the abdominal rectus muscles, and the remaining half put onto the omentum and wrapped with it. Laboratory examinations done 6 months after surgery showed recovery of her adrenal function, and 4 months later steroid supplements were able to be discontinued. Scintigraphic studies using [131I]-iodomethyl-norcholesterol ([131]I-Adosterol) demonstrated clear activity in the omentum, weak activity in the rectus muscles, and no activity in the adrenal beds. These findings suggest that the omentum may be more suitable as an implantation site for adrenal tissue than muscular pockets.

Adrenal Gland Neoplasms↗
PubMed1999

Analysis of splice variants of the fibronectin gene in thyroid carcinomas by reverse transcription-polymerase chain reaction: increased expression of oncofetal fibronectin mRNA in papillary carcinomas is not caused by the alternation in splicing.

The expression levels of each splice variant of the fibronectin gene in the normal thyroid and in thyroid tumors were examined by reverse transcription-polymerase chain reaction (RT-PCR). In thyroid papillary carcinomas, insertion of a variant exon in the ED-A and ED-B domains, and three of five types of splice variants in the IIICS domain were observed. In spite of the marked increase in the expression of oncofetal fibronectin mRNA with the IIICS sequence in papillary and anaplastic carcinomas in the previous reports, the relative expression levels of each splice variant with or without the IIICS sequence showed no difference among all the tumor types. Therefore, the much increased expression of oncofetal fibronectin mRNA in these carcinomas is not caused by the alternation in splicing, but may be caused by an increase in promoter activity or stability of mRNA of the fibronectin gene.

Adenocarcinoma, Follicular↗
PubMed1999

Comparison of antiresorptive activities of ipriflavone, an isoflavone derivative, and elcatonin, an eel carbocalcitonin.

Thirty postmenopausal women with reduced bone mineral density were divided randomly into two groups based on the chronological sequence of their first visit to the Osteoporosis Clinic of Katsuragi Hospital. Group I was given 600 mg ipriflavone orally daily and group II was weekly injected intramuscularly with 20 units elcatonin, Asu1-7 eel calcitonin (carbocalcitonin). Lumbar spine BMD was measured by dual-energy X-ray absorptiometry, and trabecular bone mineral density at the distal radius, cortical bone density, and relative cortical volume at the radial diaphysis by peripheral computed tomography before the beginning of the study and at the 4th, 8th, and 12th month. Markers of bone metabolism--serum total alkaline phosphatase, bone-specific alkaline phosphatase, tartrate-resistant acid phosphatase, osteocalcin, intact osteocalcin, PICP and ICTP, and urinary pyridinoline, deoxypyridinoline, and calcium/creatinine (Ca/Cr)--were also measured at the same interval. Plasma parathyroid hormone (PTH) and calcitonin (CT) were measured at the same time. Radial trabecular bone density showed a significantly higher rate of increase in group I (ipriflavone group) than in group II (elcatonin group) at the 4th month, whereas lumbar spine BMD showed more pronounced increase in the elcatonin group than in the ipriflavone group throughout the study period. Bone metabolism markers tended to decline in both groups. Total and intact osteocalcin showed a significant fall from the baseline throughout the study period only in the ipriflavone group. Urine pyridinoline and deoxypyridinoline showed a significant fall from the baseline at the 12th month only in the ipriflavone group. On comparing bone gainers with increase of lumbar spine BMD by 2% or more with bone losers with a decrease by 2% or more, only urine Ca/Cr was significantly different, lower in the former than in the latter, despite the general tendency for bone resorption markers to decrease in bone gainers and to increase in bone losers.

Acid Phosphatase↗
PubMed1999

Regulation of osteoclast activity.

Osteoclasts are the primary cell type responsible for bone resorption. This paper reviews many of the known regulators of osteoclast activity, including hormones, cytokines, ions, and arachidonic acid metabolites. Most of the hormones and cytokines that inhibit osteoclast activity act directly on the osteoclasts. In contrast, most of the hormones and cytokines that stimulate osteoclast activity act indirectly through osteoblasts. Particularly interesting in this regard are agents that directly inhibit activity of highly purified osteoclasts yet stimulate activity of osteoclasts that are co-cultured with osteoblasts. Recent studies have demonstrated that the primary mechanism by which bone resorptive agents stimulate osteoclast activity indirectly is likely to be up-regulation of production of osteoclast differentiation factor/osteoprotegerin ligand (ODF/OPGL) by the osteoblasts. In addition to discussing regulators of osteoclast activity per se, this paper also reviews the role of osteoclast apoptosis to limit the extent of bone resorption.

Animals↗
PubMed1999

Measurement of the expression of oncofetal fibronectin mRNA in thyroid carcinomas by competitive reverse transcription-polymerase chain reaction.

Abundant expression of oncofetal fibronectin mRNA has been observed in thyroid papillary and anaplastic carcinomas. In this study, we measured relative expression levels of oncofetal fibronectin mRNA in thyroid cancer tissues by competitive reverse transcription polymerase chain reaction (RT-PCR) using thyroglobulin mRNA as an internal control. By this method, all papillary and anaplastic carcinomas and 3 of 6 follicular carcinomas were distinguished from benign tissues, such as normal thyroid tissues, follicular adenomas, and adenomatous goiters. Furthermore, 2 anaplastic carcinomas were clearly distinguished from differentiated carcinomas. These results suggest the possibility of establishing a more accurate preoperative or postoperative diagnosis of papillary and anaplastic carcinomas by measuring the relative expression level of oncofetal fibronectin to thyroglobulin in thyroid tumors.

Adenoma↗
PubMed1999

Two germline missense mutations at codons 804 and 806 of the RET proto-oncogene in the same allele in a patient with multiple endocrine neoplasia type 2B without codon 918 mutation.

Multiple endocrine neoplasia (MEN) type 2B is a clinically distinct entity among the autosomal dominant MEN 2 syndromes. Most patients with MEN 2B carry a germline mutation (M918T) of the RET proto-oncogene, while a few carry A883F. We examined a patient with MEN 2B, but without M918T or A883F, and her relatives. Here, we report the presence in this patient of 2 germline mutations, V804M and Y806C in the same allele. While the novel Y806C was inherited from her father, its carriers (her father and brother) was not affected by MEN 2. In contrast, V804M was a de novo mutation, that has been reported in patients with familial medullary thyroid carcinoma. Combinations of mutations of the RET proto-oncogene may cause oncogenic activities different from those of single mutations.

Base Sequence↗
PubMed1999

Preoperative diagnosis of medullary thyroid carcinoma by RT-PCR using RNA extracted from leftover cells within a needle used for fine needle aspiration biopsy.

Fine needle aspiration Biopsy (FNAB) is commonly used to diagnose thyroid tumors. In some clinical situations, however, accurate diagnosis requires a more objective method than cytological examination alone. Medullary thyroid carcinomas (MTC) derive from C cells in the thyroid and express some specific messenger RNAs (mRNA), such as those transcribed from the RET proto-oncogene, the calcitonin gene, and the gene for carcinoembryonic antigen (CEA), which usually do not exist in normal thyroid follicular cells or thyroid tumors of follicular epithelial descent. Recently, we established a new method for the molecular diagnosis of thyroid tumors without additional invasion to the patient by extracting RNA for RT-PCR from the leftover cells inside the needles used for fine needle aspiration biopsy (Aspiration Biopsy-Reverse Transcription-Polymerase Chain Reaction, ABRP). By applying the ABRP method to the detection of RET, calcitonin, and CEA mRNAs, an accurate molecular-based diagnosis for MTC maybe established as an adjunct to cytological diagnosis. In this study, 35 aspirates were obtained at the time of surgery from thyroid tumors, including 11 MTCs. The expression of these mRNAs in the leftover cells inside the needles used for the aspiration was then examined. Transcripts from all three genes were detected in the samples from all 11 MTCs, but none of these mRNAs were detected in the other tumors or normal thyroid tissues. Furthermore, MTC was preoperatively diagnosed in three patients by ABRP detection of these mRNAs, and these diagnoses were confirmed by subsequent cytological and histopathological analyses. Thus RT-PCR detection of RET, calcitonin, and CEA mRNAs in FNABs may be an efficient molecular adjunct for diagnosing MTC.

Adult↗
PubMed1999

Structural conversion from non-native to native form of recombinant human epidermal growth factor by Brevibacillus choshinensis.

Brevibacillus choshinensis (Bacillus brevis) HPD31 is a very efficient producer of recombinant human epidermal growth factor (EGF). The produced EGF is secreted into the medium with high efficiency. However part of the EGF that accumulates in the medium, exists as multimeric forms which are biologically inactive. We found the bacterium has the activity to structurally convert multimeric forms to the monomeric, native ones. Optimal temperature and pH for the conversion were 40 degrees C and pH 9, respectively. The reaction was promoted in the presence of reduced glutathione or cysteine. But the cells which had been sonicated or exposed to moderate heat treatment completely lost the activity. Thus, it was presumed that the activity might be due to the enzyme(s) that catalyze the protein disulfide exchanging reaction, and that they resides on the surface of viable cells.

Bacillus↗
PubMed1999

Evidence for a potential role for HDL as an important source of cholesterol in human adrenocortical tumors via the CLA-1 pathway.

CLA-1, a human homologue of rodent scavenger receptor class B1 (SR-B1), has been identified as a receptor for high density lipoprotein (HDL) and is highly expressed in the adrenal gland. Several studies have indicated that HDL might be a source of cholesterol for steroidogenesis in the adrenal gland. In this study, we show that ACTH and its second messenger cAMP stimulated CLA-1 protein expression in a human adrenocortical cell line. We also determined whether CLA-1 plays an important role in steroidogenesis by investigating CLA-1 expression levels in various adrenal tumors including the adenomas of Cushing's and Conn's syndrome. Western blot analysis showed that CLA-1 expression was much higher in the tumors of Cushing's syndrome than in non-tumor lesions of Conn's syndrome and pheochromocytoma. We were able to detect a strong CLA-1 signal in tumors of Conn's syndrome, too. On the other hand, much less CLA-1 expression was detected in Cushing's adenoma adjacent adrenal glands. The immunohistochemical analysis showed that CLA-1 was expressed in the outer region of the adrenal cortex mainly in plasma membranes of the cortical cells but not in the medulla. These findings demonstrated for the first time that ACTH increased CLA-1 protein in cultured human adrenocortical cells, and that cortisol- and aldosterone-secreting adenomas had high CLA-1 proteins in their cell surfaces.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1999

A novel germline mutation of multiple endocrine neoplasia type 1 (MEN1) gene in a Japanese MEN1 patient and her daughter.

Familial multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder characterized by tumors of the parathyroid, anterior pituitary and gastro-entero-pancreatic endocrine tissues. The MEN1 gene has recently been cloned and its germline mutations have been considered to play an important role in the tumorigenesis of MEN1. We analyzed a Japanese MEN1 patient and her daughter for germline mutations of the MEN1 gene. The proband (60 y.o.) had primary hyperparathyroidism (PHP) and gastrinoma, and her daughter (30 y.o.) had prolactinoma. Clinical examinations revealed no evidence of PHP in the daughter. We identified a novel heterozygous germline mutation (712 A del) at codon 201 in exon 3 of the MEN1 gene in the proband. Restriction digestion analysis revealed the same mutation pattern in her daughter. These findings suggest that this family has familial MEN1 including a rare case of MEN1 with a single lesion of the pituitary. Genetic examinations are useful as diagnostic tools for any rare or variant case of familial MEN1.

Adult↗
PubMed1998

Accurate and objective preoperative diagnosis of thyroid papillary carcinomas by reverse transcription-PCR detection of oncofetal fibronectin messenger RNA in fine-needle aspiration biopsies.

Recently, the restricted expression of oncofetal fibronectin mRNA was reported in thyroid papillary and anaplastic carcinomas. In this study, by extracting RNA from the leftover cells inside the needles used for fine-needle aspiration biopsy, we establish a new method for gene diagnosis of these carcinomas without further invasiveness to the patient (aspiration biopsy-reverse transcription-PCR, ABRP). RNA was extracted from 177 fine-needle aspiration biopsies of thyroid nodules that were suspicious for malignancy, and then the gene diagnoses made by reverse transciption-PCR detection of oncofetal fibronectin mRNA were compared with cytological diagnoses. Thirty-five (94.6%) of 37 samples that were diagnosed as papillary or anaplastic carcinomas by cytological examination showed a positive result by gene diagnosis, whereas only 4 (3.7%) of 109 samples that were cytologically diagnosed negative for both carcinomas showed a positive result. Among all of the cases, 50 patients underwent surgery, and a histological diagnosis was consequently made. The sensitivity and specificity of this method were 96.9 and 100%, respectively. A combined examination using both genetic and cytological approaches may contribute to a more precise preoperative diagnosis of papillary and anaplastic carcinomas.

Adolescent↗
PubMed1998

Gene rearrangement of immunoglobulin as a marker of thyroid lymphoma.

Thyroid lymphoma occurs most commonly in the thyroid gland in association with Hashimoto's thyroiditis. Histologic findings occasionally cannot distinguish lymphoma from Hashimoto's thyroiditis, which creates a serious problem of whether treatment should be initiated. For this study, we examined 33 lymphoma tissues and 10 thyroid tissues from patients with Hashimoto's thyroiditis for the presence of gene rearrangement of immunoglobulin, which represents clonality of B-cell-derived tumors. Genomic DNA from thyroid tissues was digested with Bam H1 and Hind III restriction enzymes followed by electrophoresis. A Southern blot was performed with an IgH-JH probe or IgL-J kappa probe to detect gene rearrangement. Of the 33 lymphoma tissues, 27 (85%) showed gene rearrangement of immunoglobulin, whereas none of Hashimoto's thyroiditis tissue showed gene rearrangement. Five patients with a positive histologic diagnosis of lymphoma showed a negative gene rearrangement and were treated as having lymphoma. We encountered one case of lymphoma (plasmacytoma) in which gene rearrangement (not histologic findings) was diagnostic. Gene rearrangement of immunoglobulin can be used to detect thyroid lymphoma, particularly when the histologic diagnosis is inconclusive. The sensitivity of detecting thyroid lymphoma by the Southern blot method was about 85% in the present series.

Aged↗
PubMed1998

Mutational analysis of the RET proto-oncogene in 71 Japanese patients with medullary thyroid carcinoma.

Multiple endocrine neoplasia types 2A and 2B (MEN2A and MEN2B) and familial medullary thyroid carcinomas (FMTC) are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we screened the RET gene in 71 patients with thyroid carcinomas. The panel included representatives of 44 families carrying FMTC or MEN2, 22 sporadic medullary thyroid carcinomas (MTCs), and five MTCs without familial information. Mutations in nucleotide sequences encoding one of three specific cysteine residues in the extracellular domain of the RET protein were found in 33 of the 34 MEN2A patients and in five of the six FMTC patients examined. A mutation at codon 918, causing the substitution of threonine for methionine in the tyrosine kinase domain of the protein, was found in germline DNAs of all four patients with MEN2B and in two of the 22 patients with sporadic MTCs; codon 918 was mutated somatically in tumor DNAs from three other sporadic cases. Germline mutations of codon 768, GAG to GAC (Glu to Asp), were detected in one FMTC, in one patient with sporadic MTC, and in one of the patients without familial information. Two somatic mutations, an Asp to Gly substitution at codon 631 and a Cys to Arg substitution at codon 634, had not been reported previously. Of five germline mutations found among the 22 sporadic cases, four were confirmed as de novo mutations since in each case neither parent carried the mutation. As nearly one-fourth of the patients with sporadic MTCs carried germline mutations and 50% of their children are expected to develop MTC and other endocrine tumors, these results indicated the importance of careful clinical surveillance of family members of any patient with MTC.

Asian People↗
PubMed1998

Restricted expression of oncofetal fibronectin mRNA in thyroid papillary and anaplastic carcinoma: an in situ hybridization study.

Restricted expression of oncofetal fibronectin mRNA in the tissues of thyroid papillary and anaplastic carcinoma has recently been shown by both Northern blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR). Oncofetal fibronectin mRNA can be a target of gene diagnosis and targeted gene therapy, provided it is expressed in all cancer cells in the tissues. To investigate this criterion in thyroid cancer tissues, we measured their expression of oncofetal fibronectin mRNA using in situ hybridization. An abundant expression of oncofetal fibronectin mRNA was found in all the observed cancer cells of six papillary carcinomas and an anaplastic carcinoma, but not in the tissues of normal thyroid, Graves' disease, adenomatous goitre, follicular adenoma, follicular carcinoma or medullary carcinoma. This result encourages us to establish gene diagnosis of thyroid papillary and anaplastic carcinomas by detecting oncofetal fibronectin mRNA in biopsies.

Antigens, Neoplasm↗
PubMed1998

Intrathyroidal epithelial thymoma (ITET)/carcinoma showing thymus-like differentiation (CASTLE) exhibits CD5 immunoreactivity: new evidence for thymic differentiation.

AIMS: Cases of intrathyroidal epithelial thymoma (ITET)/carcinoma showing thymus-like differentiation (CASTLE) were examined for CD5 immunoreactivity, a feature of true thymic carcinoma, but not other thymic epithelial neoplasms or carcinomas of other sites. ITET/CASTLE, a rare, low-grade malignant neoplasm arising within the thyroid gland which resembles lymphoepithelioma-like and squamous cell carcinoma of the thymus, is postulated to arise from remnants of branchial pouch capable of thymic differentiation, but thymic differentiation in this neoplasm remains unproven. METHODS AND RESULTS: The largest published series of cases of ITET/CASTLE was examined for CD5 immunoreactivity using an anti-CD5 antibody reactive in fixed, paraffin-embedded tissue with microwave antigen retrieval. Neoplastic cells in all five cases of ITET/CASTLE studied were immunoreactive for CD5, including foci of tumour metastatic to lymph node and lung. In contrast, none of five cases of thyroid carcinoma with squamous differentiation was immunoreactive for CD5. A minority of cases of typical thyroid carcinomas showed some weak immunoreactivity for CD5. Other carcinomas of the head and neck were nonimmunoreactive for CD5. CONCLUSIONS: CD5 immunoreactivity in ITET/CASTLE is new evidence in support of thymic differentiation in this neoplasm.

Adult↗
PubMed1998

The role of ansa-to-recurrent-laryngeal nerve anastomosis in operations for thyroid cancer.

OBJECTIVE: To study the recovery in phonation after reconstruction of the recurrent laryngeal nerve (RLN) in patients whose thyroid cancer was invading the nerve, and to evaluate the role of ansa cervicalis to RLN anastomosis (ARA) in operations for thyroid cancer. DESIGN: Retrospective study. SETTING: University hospital and private thyroid clinic hospital, Japan. SUBJECTS: 34 patients with thyroid cancer who underwent reconstruction of unilateral RLN and 331 consecutive patients operated on for thyroid cancer. INTERVENTIONS: Reconstruction was direct anastomosis (DA), free nerve grafting (FNG), vagus-RLN anastomosis (VRA) or ARA, including anastomosis behind the thyroid cartilage. MAIN OUTCOME MEASURES: Maximum phonation time (34 normal subjects and 26 patients with vocal cord paralysis served as controls), laryngoscopic examination, and the ratio of reconstruction in patients who needed resection of the RLN. RESULTS: The maximum phonation time started to increase rapidly 2-5 months postoperatively in most cases as the patients' voices recovered, and 12 months after reconstruction was significantly longer than in those patients with vocal cord paralysis (P < 0.0001). It was comparable to that of the normal subjects, although the reinnervated cords were fixed in the median. The number of reconstructions in the series of 331 patients increased from 18% to 82% after we started doing ARA with the meticulous technique of anastomosis inside the thyroid cartilage. CONCLUSIONS: ARA is as effective as DA or FNG in improving phonation in patients who need resection of a unilateral RLN. As ARA has several advantages over FNG it has a definite place in operations for thyroid cancer.

Adult↗