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T Niimi

Publications and source records attributed to T Niimi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Bronchial responsiveness and angiotensin-converting enzyme gene polymorphism in sarcoidosis patients.

BACKGROUND: Angiotensin-converting enzyme (ACE) inactivates bradykinin and tachykinins, which are potent bronchoconstrictors and mediators of inflammatory reactions. It has recently been shown that an insertion (I)/deletion (D) polymorphism in the ACE gene accounts for variation in serum ACE level. We investigated bronchial responsiveness in patients with sarcoidosis to determine whether it might be associated with ACE gene polymorphism. SUBJECTS: Bronchial responsiveness was assessed in 21 patients with sarcoidosis, 21 patients with asthma, and 18 healthy control subjects. ACE polymorphism was also examined in the 21 patients with sarcoidosis. METHODS: Bronchial responsiveness was measured by recording respiratory resistance with continuous inhalation of methacholine from 49 to 25,000 microg/mL in concentration. The ACE genotype was determined using the polymerase chain reaction. RESULTS: We found a significant increase in bronchial responsiveness in sarcoidosis patients as compared with healthy control subjects (p<0.01). In the sarcoidosis group, patients with the II genotype demonstrated significantly more coughing (p<0.05) and a greater bronchial responsiveness (p<0.05) than did those with DI or DD genotypes. CONCLUSION: Patients with sarcoidosis have increased bronchial responsiveness to some extent, the degree apparently depending on the ACE genotype.

Adult↗
PubMed1997

Distinct roles of mouse laminin beta1 long arm domains for alpha1beta1gamma1 trimer formation.

Mouse embryonal carcinoma F9 cells expressing partial mouse laminin beta1 covering either the C-terminal end (delta beta1S) or the whole (delta beta1L) of the long arm were established to study the assembly and interchain disulfide-bonding of beta1 to endogenous laminin alpha1 and gamma1. Both delta beta1S and delta beta1L were disulfide-bonded to gamma1 but only delta beta1L gamma1 dimer formed a disulfide-bonded alpha1 delta beta1L gamma1 trimer which was actively secreted into the medium. Meanwhile, in the cells producing delta beta1S gamma1 dimer, the level of endogenous alpha1 beta1 gamma1 was reduced but the level of monomeric alpha1 was increased, suggesting that alpha1 was recruited to trimer formation with the delta beta1S gamma1 dimer without disulfide-bonding. This shows that the delta beta1S gamma1 dimer can associate with alpha1 but not support the disulfide-bonding at the N-terminus of the long arm of alpha1. While control cells secrete neither monomeric alpha1 nor the beta1gamma1 dimer into the medium, the delta beta1S gamma1 producing cells probably do as alpha1 delta beta1 gamma1 trimer. We thus propose that the N- and C-termini of the long arm of laminin beta1 have distinct roles for trimer formation.

Animals↗
PubMed1997

Differentiation-dependent expression of laminin-8 (alpha 4 beta 1 gamma 1) mRNAs in mouse 3T3-L1 adipocytes.

We report that laminin-8 (alpha 4 beta 1 gamma 1) is the specific isoform of laminin synthesized in adipocytes. Reverse transcription-polymerase chain reaction (RT-PCR) of mRNA from mouse 3T3-L1 cells with paired primers for alpha 1, alpha 2, alpha 3, alpha 4, alpha 5, beta 1, beta 2, beta 3, gamma 1 and gamma 2 laminins yielded amplified fragments only for alpha 4, beta 1 and gamma 1. A polyclonal antibody against mouse laminin-1 (alpha 1 beta 1 gamma 1) precipitated alpha 4 in addition to beta 1 and gamma 1, while the antibody against a deduced peptide sequence of mouse alpha 4 in addition to beta 1 and gamma 1 in addition to alpha 4. Thus, laminin-8 (alpha 4 beta 1 gamma 1) is the only isoform expressed in 3T3-L1 cells. Northern blots showed that the levels of alpha 4, beta 1 and gamma 1 mRNAs increased 2.5-fold during adipose conversion of 3T3-L1 cells. A 1062 bp cDNA fragment cloned by RT-PCR demonstrated a polymorphism in the mouse alpha 4 gene which would lead to five amino acid changes in the domain G.

3T3 Cells↗
PubMed1997

Expression of the long arm sequence of mouse laminin alpha1, beta1, or gamma1 chain in COS1 cells and assembly of monkey-mouse hybrid laminin.

Mouse laminin alpha1, beta1, or gamma1 sequence covering truncated regions of the long arm was transiently expressed in monkey COS1 cells. Unlike natural laminins, in which only alpha beta gamma trimers are selectively assembled and disulfide-bonded at the long arm, a large fraction of mouse chains formed disulfide-bonded homopolymers. However, a small fraction of mouse beta1 (or gamma1) formed hybrid beta1gamma1 dimers with endogenous monkey gamma1 (or beta1). These hybrid beta1gamma1 dimers formed alpha1 beta1 gamma1 trimer with monkey alpha1. Mouse alpha1 also formed disulfide bonds with monkey beta1gamma1 dimer. Thus, a common mechanism is shared by laminin chains of different animal origins. Sequences in the E8 region at the C-terminal end of the long arm were crucial for this chain-selective assembly. When the C-terminal sequence of mouse beta1 long arm was extended beyond the alpha-loop, the hybrid trimer formation was diminished. This supported the model of altered chain arrangement around the alpha-loop.

Animals↗
PubMed1997

Cloning of cDNAs encoding Bombyx homologues of Cdc2 and Cdc2-related kinase from eggs.

In diapausing eggs of the silkworm Bombyx mori, embryonic cells are arrested at G2 phase. The ability to undertake cell division is resumed in the course of diapause termination caused by such a treatment as acclimation to 5 degrees C. As an initial trial to investigate the relationship between diapause and embryonic cell cycling, we have cloned and sequenced two Bombyx cDNAs encoding two distinct cdc2-related Ser/Thr protein kinases. One (Bm cdc2) encoded a 37.0 kDa protein which had all of the domains characteristic of other Cdc2 kinase. The other (Bcdrk) encoded a 45.1 kDa protein that was most similar to Drosophila and human cdc2-related protein kinases (Dcdrk protein and PISSRLE kinase). Northern blot analysis was carried out to examine levels of Bm cdc2 and Bcdrk mRNA during embryogenesis of non-diapause eggs. The result demonstrated that the mRNA level of Bm cdc2 appeared to correspond to the activity of nuclear/cellular division in non-diapause eggs, and that the developmental profile in the level of Bcdrk mRNA was somewhat different from that of Bm cdc2 mRNA.

Amino Acid Sequence↗
PubMed1996

NMR studies of the effects of the 5'-phosphate group on conformational properties of 5-methylaminomethyluridine found in the first position of the anticodon of Escherichia coli tRNA(Arg)4.

5-Methylaminomethyluridine (mnm5U) exists in the first position of the anticodon (position 34) of Escherichia coli tRNA4Arg for codons AGA/AGG. In the present study, the temperature dependence of the ribose-puckering equilibrium of pmnm5U was analyzed by proton NMR spectroscopy. Thus, the enthalpy difference (delta H) between the C2'-endo and C3'-endo forms was obtained at 0.65 kcal.mol-1. By comparison of the delta H values of pU and pmnm5U, the 5-substitution was found to increase the relative stability of the C3'-endo form over the C2'-endo form significantly (by 0.56 kcal.mol-1). Furthermore, this conformational "rigidity" was concluded to depend on the 5'-phosphate group, because nucleoside U exhibits only a negligible change in the ribose-puckering equilibrium upon the 5-methylaminomethyl substitution. Further NMR analyses and molecular dynamics calculations revealed that interactions between the 5-methylaminomethyl and 5'-phosphate groups of pmnm5U restrict the conformation about the glycosidic bond to a low anti form, enhancing steric repulsion between the 2-carbonyl and 2'-hydroxyl groups in the C2'-endo form. This intrinsic conformational rigidity of the mnm5U residue in position 34 may contribute to the correct codon recognition.

Anticodon↗
PubMed1996

Major identity determinants in the "augmented D helix" of tRNA(Glu) from Escherichia coli.

By a kinetic analysis of 59 variant transcripts of Escherichia coli tRNA(Glu) with glutamyl-tRNA synthetase (GluRS), the U11.A24 base-pair, the U13.G22..A46 base-triple, and the lack of residue 47 (delta47) were found to serve as major determinants for tRNA(Glu) identity. This is the first system for which major identity determinants are reported to be clustered in the "augmented D helix", consisting of the D stem with some neighboring residues and the variable loop. Other identity determinants are U34, U35, C36 and A37 in the anticodon loop, and G1.C72 and U2.A71 in the acceptor stem. Phosphate-group protection by GluRS from ethylnitrosourea was observed most strongly for the minor groove side of D-stem helix, indicating that GluRs tightly binds to the D stem for recognition, on the minor groove side, of the potent identity-determinant groups of the U11.A24 and U13.G22 base-pairs. A46 is not involved in direct recognition by GluRS; the U13.G22..A46 base-triple is required probably for formation of the structural features that are recognized by GluRS. In this context, the essential role of characteristic delta47 in tRNA(Glu) identity may be to maintain the U13.G22..A46 base-triple.

Anticodon↗
PubMed1996

Structure of the Bombyx sorbitol dehydrogenase gene: a possible alternative use of the promoter.

In an initial effort to understand the molecular mechanism of how low temperature induces sorbitol dehydrogenase gene expression in diapause eggs of the silkworm, the sorbitol dehydrogenase gene was isolated from a Bombyx genomic library using a cDNA encoding the Bombyx homologue of mammalian sorbitol dehydrogenase as a probe. The gene extended for about 10 kb, consisting of eight exons and seven introns. Four TATA motifs were found in the 5' upstream region of the gene, without CCAAT. AATTAA, instead of AATAAA, was localized in the upstream region of the polyadenylation site. Although a single copy of this gene was present per haploid genome, 1.2 kb and 1.1 kb transcripts were found from yolk cells in diapause eggs and from larval fat-body cells, respectively. The two major transcription initiation sites corresponding to both transcripts were localized at 355 and 226 base pairs upstream from the transition start site, indicating an alternative use of promoter. The 5'-upstream region of the gene contained a consensus sequence, TGA(A/T)AA(A/G/T), that has been found in insect genes expressed mainly in larval and pupal fat bodies. It also contained three kinds of sequences similar to cis-elements recognized by members of the steroid receptor superfamily, such as chicken ovalbumin upstream promoter transcription factor (COUP-TF)/Drosophila Seven up (SVP), Drosophila hormone receptor 39 (DHR39) and Bombyx fushi tarazu transcriptional factor 1 (BmFTZ-F1).

Alternative Splicing↗
PubMed1996

[Sociomedical study of centenarians in Nagoya City].

The purpose of this study was to assess the background to the longevity of 36 centenarians in Nagoya city and to compare 14 institutionalized centenarians out of those 36 with 202 individuals in the 70-99 age group in our special nursing home, particularly with regard to blood chemistry and immunity tests. The reasons for their social longevity in terms of profile appeared to be attention to eating habits, abstention from smoking and drinking, occupations with adequate exercise. The incidence of dementia was 65.6% among them. We evaluated centenarians from the viewpoint of Hasegawa's Dementia Scale (HDS) and comprehensive functional assessment of the elderly consisted of the revised version of Hasegawa's Dementia Scale (HDSR), and examination of activity of daily living (ADL), physical perception, and social life. All were positively associated. Thus centenarians independent of physical assistance demonstrated significantly higher systolic blood pressure, and respective scores for HDS, HDSR, ADL, physical perception and social life than their dependent counterparts, were less likely to be institutionalized and suffered from fewer disorders. In particular none were diagnosed as positive for cerebral hemorrhage, infarction and dementia. Age demonstrated significant positive or negative correlation with the following values in blood chemistry and immunity tests: blood cell counts, hemoglobin concentration, hematocrit value, albumin, total protein, total cholesterol, low density lipoprotein cholesterol, creatinine, blood cell nitrogen, uric acid, helper T cell, and IgA immunoglobulin.

Activities of Daily Living↗
PubMed1996

[Acute myocardial infarction with idiopathic thrombocytopenic purpura in an elderly patient].

A 71-year-old woman complained of gingival bleeding and epistaxis, and was given a diagnosis of idiopathic thrombocytopenic purpura. She was successfully treated with orally administered prednisolone and azathioprine. She experienced a relapse when she was 77 years old, and immunosuppressive therapy was not effective. Platelet transfusion was performed. She died because of massive gastrointestinal bleeding. An infarct was found in the left anterior part of the myocardium at autopsy. Disseminated intravascular coagulation was not detected on pathological investigation. Abnormal platelet aggregation may be important in the pathogenesis of thrombotic disease in thrombocytopenia.

Aged↗
PubMed1995

Biosensing of benzene derivatives in the environment by luminescent Escherichia coli.

Sensitive and convenient biosensing of environmental pollutants has been developed by fusing a gene of firefly luciferase to the TOL plasmid. TOL plasmid of Pseudomonas putida encodes a series of enzymes for degradation of benzene and its derivatives. The expression of these enzymes is controlled with the regulating proteins xylR and xylS, whose promoters are activated in the presence of aromatic compounds. The structural gene of firefly luciferase, as a reporter enzyme, was inserted under the control of the promoter of xylS protein, and gene fusion plasmid pTSN316 was constructed. The recombinant Escherichia coli transformed with this plasmid was applied to the environmental biosensing of benzene derivatives. The expression of luciferase was induced in the presence of aromatic compounds and the lower detection limit for m-xylene was 5 microM.

Benzene↗
PubMed1995

[A 115-year-old woman: the oldest individual in Japan].

The purpose of this study was to assess the background to the longevity of a 115-year-old woman who was the oldest individual in Japan as of September, 1994. The secrets of her social and medical profile appeared to be hereditary factors, well-balanced meals, no smoking or drinking, sufficient sleep and adequate exercise. From the viewpoints of psychological aspects and comprehensive functional assessment of the elderly, she clearly has a tenacious personality. Furthermore, she has maintained independence in her activities of daily living, and did not suffer from senile dementia until 107 years of age. From the medical standpoint, she has suffered from transient hypertension, but her left ventricle function has remained within the normal echocardiography range and no greatly abnormal values have been observed in blood chemistry tests. She has suffered from pneumonia and urinary tract infection many times since the age of 109, and on these occasions she was promptly admitted to our hospital and received appropriate medical treatment. We consider that this also played an important role in her longevity.

Activities of Daily Living↗
PubMed1995

[Differential cooling and perfusion: a reasonably safe method of systemic organ protection during surgery for acute type A aortic dissection].

During surgery for acute type A aortic dissection we have developed a new technique of cerebral and systemic organ protection according to susceptibility to ischemic damage. After cardiopulmonary bypass is established, patient is cooled to the rectal temperature of 30 degrees C. Then cardiopulmonary bypass is temporarily discontinued, the ascending aorta is opened, and myocardial protection is achieved by retrograde coronary sinus cold blood cardioplegia. To perform distal open repair, all 3 brachiocephalic arteries are cannulated with 13 F balloon catheters through the aortic lumen, and perfused with cold blood (12 degrees C) (10 ml/kg/min), while an additional larger balloon catheter (24 F) is inserted in the true lumen of the descending aorta, and systemic perfusion with warmer blood (28 degrees C) (1-2 l/min) is started. When the distal repair is completed, cardiopulmonary bypass is resumed and the systemic rewarming is started, meanwhile proximal repair is accomplished. Between December 1993 and August 1994, 10 patients were operated on with this method. Mean duration of cardiopulmonary bypass was 182 minutes (113 to 290), and mean duration of DCP was 63 minutes (18 to 130). Operative mortality was 10% (1/10). The technique of "differential cooling and perfusion" has been demonstrated to provide excellent cerebral and visceral protection and to minimize drawbacks associated with deep hypothermic methods necessitating prolonged cardiopulmonary bypass.

Acute Disease↗
PubMed1995

[A case of acute eosinophilic pneumonia with acute onset of dyspnea].

A 16-year-Old boy was admitted with acute onset of fever, cough, and dyspnea. Chest radiography showed diffuse infiltrated shadow and right pleural effusion. BALF revealed a high level of eosinophils (56.8%), and TBLB specimen showed infiltration of inflammatory cells, chiefly eosinophils. Symptoms and radiographic findings resolved spontaneously within a few days after admission. Acute eosinophilic pneumonia was diagnosed as in the case reported by Allen et al. However, the present patient had a high IgE level and history of atopic allergic rhinitis. In more than one third of previously reported cases in Japan, there was a history of atopy, unlike in Allen's report.

Acute Disease↗
PubMed1995

[Severe cases of pulmonary tuberculosis required mechanical ventilation].

We report severe cases of pulmonary tuberculosis with respiratory failure who required mechanical ventilation. Of 99 patients with pulmonary tuberculosis admitted to Daido Hospital from November 1991 to November 1993, 6 patients had been mechanically ventilated. Four of these 6 patients were vagrants and had long delay from onset of the symptom to the admission. Chest X-rays of ventilated patients showed bilateral, extensive shadows consistent with those of typical pulmonary tuberculosis, and a large number of acid-fast bacilli were detected in their sputa. Though all ventilated patients except one HCV carrier had no underlying disease, they showed remarkable emaciation and malnutrition. They also showed weak PPD-skin reactions and reduced number of lymphocytes that suggested immunological disorders. Four cases have recovered, so we conclude that mechanical ventilation is necessary and useful for the treatment of severe cases of pulmonary tuberculosis.

Adult↗
PubMed1995

[A case of posttraumatic tricuspid regurgitation-surgery combined with tricuspid valve repair and coronary artery bypass grafting].

A case of tricuspid regurgitation due to nonpenetrating chest trauma was presented. A 64-year-old female patient, who had a history of blunt chest trauma in a car accident 15 years ago, was admitted because of dyspnea on exertion and sensation of epigastric distress of 8 years duration. The patient's echocardiogram and right ventriculogram "demonstrateol massive tricuspid regurgitation and enlargement of both the right atrium" and the right ventricle. Additionally the coronary arteriogram showed severe stenotic lesion of the proximal left anterior descending coronary artery. The patient underwent reconstructive surgery for the tricuspid valve combined with coronary artery bypass grafting using a left internal mammary artery graft successfully. The torn chordae tendinae of the anterior and posterior leaflet were reattached to the leaflet edges with polytetrafluoroethylene (PTFE) sutures and the size of a dilated annulus was reduced using 30 mm Carpentier ring.

Chronic Disease↗