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Biomedical subjects

T Niimi

Publications and source records attributed to T Niimi.

At least 37 records · Page 2Linked to original sources
PubMed2000

Structure of the VAP-peptide (BmACP-6.7) gene in the silkworm, Bombyx mori and a possible regulation of its expression by BmFTZ-F1.

The VAP-peptide (BmACP-6.7) is a hydrophobic peptide localized in adult cuticle of the silkworm, Bombyx mori. We isolated and characterized the VAP-peptide gene as a useful marker gene to analyze molecular mechanisms of terminal differentiation processes in the adult. The gene is composed of two exons interrupted by one intron. The 5' upstream promoter region is shown to bear a nucleotide sequence similar to the cis-element that is recognized and bound by the Bombyx mori FTZ-F1 protein (BmFTZ-F1). Expression of the BmFTZ-F1 gene preceded expression of the VAP-peptide gene and injection of 20-hydroxyecdysone suppressed the expression of both genes. An in vitro binding assay indicated direct interaction of BmFTZ-F1 with the VAP-peptide gene promoter sequence. Therefore, BmFTZ-F1 is proposed to be a possible factor regulating the stage-specific expression of the VAP-peptide gene towards adult life.

Amino Acid Sequence↗
PubMed2000

Lack of association with interleukin 1 receptor antagonist and interleukin-1beta gene polymorphisms in sarcoidosis patients.

Interleukin-1beta (IL-1beta) and its endogenous antagonist, the interleukin-1 receptor antagonist (IL-1ra), play important roles in immune responses. In sarcoidosis, IL-1beta is reported to be increased whereas IL-1ra is decreased. It has recently been shown that polymorphisms in the IL-1ra and IL-1beta genes may account for variation in the two proteins. These polymorphisms are also reported to be associated with several autoimmune diseases. Since this might be expected to affect sarcoidosis, an investigation of 108 sarcoidosis patients and 113 healthy control subjects was performed. The IL-1ra genotype was determined using the polymerase chain reaction (PCR), and the IL-1beta genotype by PCR restriction fragment length polymorphism. We found no significant differences in IL-ra and IL-1beta genotypes between sarcoidosis patients and healthy controls. Furthermore, there was no association between the IL-1beta genotype and the roentgenographic stage, disappearance of chest X-ray shadows or organ involvement. In conclusion, there is no bias in the IL-1ra and IL-1beta genotype in Japanese sarcoidosis patients.

Female↗
PubMed2000

Human herpesvirus 8 is not associated with sarcoidosis in Japanese patients.

STUDY OBJECTIVES: The etiology of sarcoidosis remains unknown, but recently it was reported that human herpesvirus 8 (HHV-8) may be detected in sarcoid tissue in a high proportion of patients. This study was performed to determine whether HHV-8 is implicated in sarcoidosis in Japan. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMCs) were obtained from 100 patients with sarcoidosis and 100 healthy donors living in central Japan. Additionally, 19 samples of sarcoid tissue, 10 of tuberculous tissue, and 10 of lung cancers were examined. DNA was extracted from PBMC or tissue samples, and a hemi-nested polymerase chain reaction assay was performed for HHV-8 detection. RESULTS: In the PBMC study, the detection rates for HHV-8 in patients with sarcoidosis and in normal donors were 2% and 1%, respectively, the difference not being significant (p>0.99). In the tissue study, HHV-8 was detected in 10.5% of sarcoid and in 15% of nonsarcoid tissues, again not a significant difference (p>0.99). CONCLUSIONS: From these results, we conclude that HHV-8 is not implicated in sarcoidosis in Japanese patients.

Antibodies, Viral↗
PubMed2000

[A case of Wegener's granulomatosis with pachymeningitis].

A 62-year-old woman who had been receiving corticosteroid therapy for pachymeningitis since 1997 was admitted to our hospital when an abnormal shadow was noticed in her chest radiograph. In bronchial and nasal mucosal biopsies, the findings of a necrotic granulomatous lesion and vasculitis were compatible with Wegener's granulomatosis, although this is rarely seen with pachymeningitis. After further corticosteroid therapy together with cyclophosphamide treatment, the size of the thoracic X-ray shadow decreased. Methicillin-resistant Staphylococcus aureus (MRSA) was cultured from the sputum and the nasal fluid, and may have contributed to the advance of the disease in the airway. This case will require continuing careful observation.

Female↗
PubMed2000

Vitamin D receptor gene polymorphism and calcium metabolism in sarcoidosis patients.

BACKGROUND: Hypercalcemia has been recognized as an important complication of sarcoidosis, caused by overproduction of the active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) at sites of granulomatous reactions. Polymorphism of the vitamin D receptor (VDR) gene has recently been shown to be related to bone mineral density, and also associated with hyperparathyroidism and risk of granulomatous disease. In light of the possible impact on hypercalcemia of sarcoidosis, an investigation of calcium metabolism and polymorphism of the VDR gene in sarcoidosis patients was carried out. METHODS: Genotypes were determined using the polymerase chain reaction and restriction fragment length polymorphism. Maximum calcium, 1,25(OH)2D3, and intact PTH levels were also determined. RESULTS: Depressed PTH levels were found in sarcoidosis patients, especially in those with the bb genotype, but there was no difference in 1,25(OH)2D3 levels among the VDR genotypes, and this polymorphism also had no association with onset of hypercalcemia. CONCLUSION: From these results, we speculate that although the VDR gene polymorphism may affect the serum PTH level, it is not a risk factor for hypercalcemia in sarcoidosis.

Adult↗
PubMed1999

Serum lysozyme levels and clinical features of sarcoidosis.

Serum lysozyme is used as a marker of sarcoidosis disease activity. In this study we examined the association between lysozyme levels and the clinical features of sarcoidosis and thus the clinical usability of this parameter in a large population. One hundred ten sarcoidosis patients from central Japan were examined for clinical features and serum lysozyme level at the first visit to our hospital and on a regular basis thereafter. The sensitivity of lysozyme for predicting sarcoidosis was 79.1%, whereas that of serum angiotensin-converting enzyme (ACE) was 59.0%. Even in the cases without an elevated serum ACE level, a value of 72.1% was obtained. The serum lysozyme level demonstrated a significant tendency to increase with the number of organs involved (p < 0.01). There were significant differences among the four radiographic stages (p < 0. 05). The maximum serum lysozyme levels of patients without a disappearance of abnormal shadows on chest radiography within 5 years were significantly greater than those of individuals with a disappearance (p < 0.05). A positive correlation between serum lysozyme and serum ACE levels was observed. Because serum lysozyme is much less specific for sarcoidosis than serum ACE, its diagnostic value may be limited. However, the sensitivity was high even when serum ACE levels were within normal limits and correlated well with clinical features in sarcoidosis. Therefore, this parameter seems suitable for disease monitoring in proven cases.

Clinical Enzyme Tests↗
PubMed1999

A Drosophila gene encoding multiple splice variants of Kazal-type serine protease inhibitor-like proteins with potential destinations of mitochondria, cytosol and the secretory pathway.

A Drosophila gene (KAZ1), mapped to cytological position 61A1-2 on chromosome 3, has been cloned and found to encode multiple splice variants of Kazal-type serine protease inhibitor-like proteins. KAZ1 consists of five exons and four alternatively retained introns to produce six transcripts of type AB, C1, C2, C3, D and E. The AB transcript contains two ORFs, of which the upstream one produces a polypeptide alpha, which has a mitochondrial sorting signal. Localization to mitochondria was confirmed by expression in COS1 cells. The downstream ORF is shared partially with type C1, C2, C3, D and E transcripts and produces polypeptides beta, gamma, delta and epsilon when expressed in Drosophila cells. Type C1, C2 and C3 transcripts differ only in the 5'-noncoding sequence and thus all produce type gamma. Polypeptides gamma and epsilon have a signal sequence at their N-termini and are secreted into the medium while beta and delta lack this sequence and remain in the cytoplasm. Isoforms beta and epsilon share a common C-terminal sequence distinct from that shared by polypeptides gamma and delta. The N-terminal sequences of isoforms beta to epsilon contain a PEST region which could induce rapid intracellular degradation of isoforms beta and delta. Sequence analysis of the Kazal-type domain suggests a similar folding pattern as observed for rhodniin and SPARC/BM-40. Northern analysis and in situ hybridization showed that the type C3 transcript is predominant and the expression is highest in midgut at larval stage.

Amino Acid Sequence↗
PubMed1999

Brachyury (T) expression in embryonal carcinoma P19 cells resembles its expression in primitive streak and tail-bud but not that in notochord.

Brachyury (T) is involved in mesoderm induction during early mouse development. T expression in embryonal carcinoma P19 cells, which differentiate into mesoderm derivatives in vitro, was studied. Endogenous T expression in P19 cells was transiently induced when the cells were allowed to form aggregates. This expression was enhanced by dimethyl sulfoxide. In situ hybridization showed that T expressing cells formed clusters on the aggregates. Transfection of plasmids encoding reporter genes under the control of the upstream region of T showed that the sequence up to -351 bp can resemble the differentiation-dependent expression of T in P19 cells. To define the promoter region regulating T expression, transgenic mice carrying LacZ under the control of the upstream region were prepared. The region up to -351 bp is sufficient to direct the expression in the primitive streak and tail-bud. The upstream region up to -2400 bp does not support expression in the notochord. The sequence between -987 and -585 bp enhances expression in the primitive streak and tail-bud. In the tail-bud where new cells for elongation of the anteroposterior axis were continuously supplied, the sequence up to -987 bp drove lacZ expression in gut endoderm and prospective neuroectoderm as well as in mesoderm derivatives.

Animals↗
PubMed1999

Vitamin D receptor gene polymorphism in patients with sarcoidosis.

The active form of vitamin D, 1,25-dihydroxyvitamin D(3), is known to be produced at sites of granulomatous reactions in sarcoidosis. 1, 25-dihydroxyvitamin D(3) has multiple immunomodulatory effects, and acts as a promoter of multinucleated giant cell formation. Polymorphism of the vitamin D receptor (VDR) gene has recently been shown to be related to bone mineral density, and also associated with hyperparathyroidism and risk of prostatic carcinoma. Considering that this might affect sarcoidosis, we investigated polymorphism of the VDR gene in 101 patients with sarcoidosis and 105 healthy control subjects. Their genotypes were determined using polymerase chain reaction (PCR) and restriction fragment length polymorphism. In the patients with sarcoidosis, the BB, Bb, and bb genotypes accounted for 1.0%, 37.6%, and 61.4%, whereas in healthy control subjects the figures were 1.0%, 20.0%, and 79.0%, respectively. The difference in the genotype distribution between healthy control subjects and sarcoidosis patients was significant (p < 0.05) with the frequency of the B allele being elevated (p < 0.05). From the result, we suggest that in VDR gene polymorphism the B allele might be a genetic risk factor for sarcoidosis.

Alleles↗
PubMed1999

Direct regulatory interaction of the eyeless protein with an eye-specific enhancer in the sine oculis gene during eye induction in Drosophila.

The Pax-6 gene encodes a transcription factor with two DNA-binding domains, a paired and a homeodomain, and is expressed during eye morphogenesis and development of the nervous system. Pax-6 homologs have been isolated from a wide variety of organisms ranging from flatworms to humans. Since loss-of-function mutants in insects and mammals lead to an eyeless phenotype and Pax-6 orthologs from distantly related species are capable of inducing ectopic eyes in Drosophila, we have proposed that Pax-6 is a universal master control gene for eye morphogenesis. To determine the extent of evolutionary conservation of the eye morphogenetic pathway, we have begun to identify subordinate target genes of Pax-6. Previously we have shown that expression of two genes, sine oculis (so) and eyes absent (eya), is induced by eyeless (ey), the Pax-6 homolog of Drosophila. Here we present evidence from ectopic expression studies in transgenic flies, from transcription activation studies in yeast, and from gel shift assays in vitro that the EY protein activates transcription of sine oculis by direct interaction with an eye-specific enhancer in the long intron of the so gene.

Animals↗
PubMed1999

[Nontuberculous mycobacterial disease in a general hospital].

Annual incidence of nontuberculous mycobacterial (NTM) disease has been gradually increasing in the last 10 years in Japan. It is likely to encounter this disease not only in hospitals specialized in mycobacterial diseases but also in general hospitals. NTM were isolated from 97 cases between January 1990 and June 1996 at our hospital. Out of them, 41 patients were diagnosed as NTM disease. Mycobacterium avium complex (MAC) was the most frequent pathogens (68.3%) and M. kansasii (22%) was the next. Other pathogens were M. chelonae (4.9%), M. fortuitum (2.4%) and M. szulgai (2.4%). Results obtained in our hospital were very similar to the rates which have been reported previously. Patients with MAC infection showed relatively poor prognosis (eight patients were died out of 28 patients with MAC) in this study compared with the cases reported in previous papers, and this result could be explained by the severity of illness when they were admitted to our hospital, the insufficiency of the initial treatment which should be started with the combined use of three to four antibacterial drugs including clarithromycin, and to a low dosage of clarithromycin compared with conventionally adopted dosage. Unlike tuberculosis, human to human transmission is considered to be negligible in the case of NTM disease, and general hospitals are able to provide medical care to the patients with NTM disease. Rather, if general hospitals which are located in the region near to the patients residence can play more active role in the treatment of NTM disease, it would be more beneficial to patients requiring long-term follow-up observation. Based on the result that similar therapeutic results were obtained for infections with other NTM as reported in previous papers, it is indicated that general hospitals are able to provide medical care to patients with NTM disease if therapeutic regimens recommended by specialist are sufficiently understood and applied.

Female↗
PubMed1998

Structural basis for binding of the plasmid ColIb-P9 antisense Inc RNA to its target RNA with the 5'-rUUGGCG-3' motif in the loop sequence.

The sequence 5'-rUUGGCG-3' is conserved within the loop regions of antisense RNAs or their targets involved in replication of various prokaryotic plasmids. In IncIalpha plasmid ColIb-P9, the partially base paired 21-nucleotide loop of a stem-loop called structure I within RepZ mRNA contains this hexanucleotide sequence, and comprises the target site for the antisense Inc RNA. In this report, we find that the base pairing interaction at the 5'-rGGC-3' sequence in the hexanucleotide motif is important for interaction between Inc RNA and structure I. In addition, the 21-base loop domain of structure I is folded tighter than predicted, with the hexanucleotide sequence at the top. The second U residue in the sequence is favored for Inc RNA binding in a base-specific manner. On the other hand, the upper domain of the Inc RNA stem-loop is loosely structured, and maintaining the loop sequence single-stranded is important for the intermolecular interaction. Based on these results, we propose that a structural feature in the loop I domain, conferred probably by the conserved 5'-rUUGGCG-3' sequence, favors binding to a complementary, single-stranded RNA. This model also explains how the RepZ mRNA pseudoknot, described in the accompanying paper (Asano, K., and Mizobuchi, K. (1998) J. Biol. Chem. 273, 11815-11825) is formed specifically with structure I. A possible conformation adopted by the 5'-rUUGGCG-3' loop sequence is discussed.

Bacterial Proteins↗
PubMed1998

Combined surgery for mitral regurgitation associated with extensive annular calcification and left main coronary artery disease.

Although extensive calcification of the mitral annulus is encountered infrequently, it presents a formidable problem in mitral valve surgery. We describe a case of severely calcified mitral annulus associated with grade IV mitral regurgitation in addition to left main coronary artery disease. The patient was a 66-year-old woman who successfully underwent thorough excision of the calcified bar, annular reconstruction with a autologous pericardial strip, mitral valve replacement with a mechanical prosthesis, and double coronary artery bypass grafting using arterial grafts.

Aged↗
PubMed1998

Genetic polymorphism of the angiotensin-converting enzyme (ACE) in asthmatic patients.

Angiotensin-converting enzyme (ACE) inactivates bradykinin, substance P and neurokinin A, which are believed to play important roles in the pathogenesis of asthma, especially in neurogenic inflammation. It has recently been shown that an insertion (I)/deletion (D) polymorphism in the ACE gene accounts for variation in serum ACE levels. There are thus three genotypes (insertion homozygote, II; deletion homozygote, DD; heterozygotes, DI). The serum ACE level with the DD type is reported to be about double that of the II type and intermediate in the DI case. In the present study, we examined whether asthma is linked with this ACE gene polymorphism. Seventy-one patients with asthma (27 males and 44 females) and 142 sex- and age-matched healthy controls were determined for their genotype by the polymerase chain reaction (PCR) method. Twenty-five asthmatics demonstrated the II type (35.2%), 37 the DI type (52.1%), and nine the DD type (12.7%). There were no significant differences in the distributions of genotypes and serum ACE levels between healthy controls and patients. No significant differences were evident in serum IgE levels, age at onset, proportion of atopic type patients and severity of asthma among the three genotypes. We did not find any association between asthma and the ACE gene polymorphism in this study.

Asthma↗
PubMed1998

A hydrophobic peptide (VAP-peptide) of the silkworm, Bombyx mori: a unique role for adult activity proposed from gene expression and production at the terminal phase of metamorphosis.

A unique hydrophobic peptide (VAP-peptide) isolated from male adult heads of the silkworm, Bombyx mori, has been shown to act as a synergist to the diapause hormone when administered exogenously. Here, we investigated the true role of the endogenous VAP-peptide on differentiation and development of adult organs in the silkworm. By northern blot analyses, the VAP-peptide gene was shown to be exclusively expressed at the terminal phase of adult development in epithelial tissues, especially in the wing and the thoracic integument. In situ hybridization analysis revealed that the gene was highly expressed in the epidermal cells of the wing vein and the thoracic integument. The stage- and tissue-dependent gene expression were clearly correlated to the accumulation profile of VAP-peptide. In the adult thoracic integument, VAP-peptide was predominantly deposited in the cuticle layer. Affinity chromatography indicated the ability of VAP-peptide to bind to chitin. Based on its expression patterns, localization, and chemical properties, VAP-peptide is conceived to be a structural protein that participates in mechanical strengthening of specific cuticle structures, supporting their physical requirements in the adult life of the silkworm.

Animals↗
PubMed1998

p53 mutations in non-small-cell lung cancers occurring in individuals without a past history of active smoking.

Accumulating evidence suggests that the p53 gene is a good target for molecular epidemiological studies. We previously reported an association between the presence of p53 mutations and lifetime cigarette consumption. Although over 675 p53 mutations have been reported in lung cancers in the literature thus far, very little is known about the nature of such changes in lung cancers in the absence of a smoking background. In the present study, we therefore analysed 69 non-small-cell lung cancer specimens from individuals without any history of active smoking and identified p53 mutations in 26% of the cases. Statistical analysis of the present cohort of non-smokers also showed absence of significant relationship between p53 mutations and age, sex, histological type or disease stage. Comparison of mutational spectra between the present results in non-smokers and previously reported mutations in smokers clearly demonstrated G:C to T:A transversions to be significantly less frequent in non-smokers than in smokers (OR 5.35, 95% CI 1.77-16.12). Interestingly, G:C to C:G and G:C to A:T mutations were also observed in tumours of non-smokers at similar frequencies to G:C to T:A mutations, suggesting that these mutations can occur relatively frequently in the absence of active smoking. This study is, to our knowledge, the largest so far analysing a well-defined cohort of non-smokers in a single laboratory.

Adult↗
PubMed1998

The "T-shaped" thoracotomy for pericardiectomy after midline crossed IMA grafting.

In the presence of an internal mammary artery graft crossing the mid-sternal line, a median sternotomy may jeopardize the graft and consequently bring a hemodynamic compromise. We describe a case of successful radical pericardiectomy for postoperative constrictive pericarditis using a "T-shaped" thoracotomy in a 68-year-old male patient who had a right IMA graft to the left anterior descending coronary artery.

Aged↗