Search PubMed⌕ Search

Biomedical subjects

T Niimi

Publications and source records attributed to T Niimi.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Surgery of thoracoabdominal aortic aneurysm associated with coronary artery disease].

A 67-year-old man underwent combined surgery for thoracoabdominal aortic aneurysm and coronary artery disease. Preoperative computed tomographic scan and aortography showed a large aneurysm in diameter of 7 cm locating from lower half of the descending thoracic aorta to just above the celiac artery. Coronary arteriography revealed severe stenosis (99%) of the proximal left anterior descending artery (LAD). The patient was operated on in October 1994, via a thoracoabdominal approach by entering the thorax in the 8th intercostal space and the retroperitoneal space through a paramedian incision after division of the costal arch. An additional standard thoracotomy was performed in the 5th intercostal space, through which a left internal thoracic artery (LITA) was mobilized. After the proximal descending thoracic aorta as well as the right femoral artery was cannulated for arterial perfusion, and the main pulmonary artery as well as the right femoral vein for venous return, total cardiopulmonary bypass was established and a LITA graft was anastomosed to the LAD under cardioplegic arrest. Thereafter the aneurysm was replaced with an 18 mm dacron prosthesis while the LITA graft and coronary arteries were reperfused and cardiac beating was resumed. His postoperative course was uncomplicated. Postoperative angiography demonstrated satisfactory repair of the aorta and a fully patent LITA graft.

Aged↗
PubMed1994

Characterization of the secondary structure of an oligonucleotide corresponding to the autocleavage site of a precursor RNA from bacteriophage T4.

We studied the secondary structure of an RNA fragment (GUUUCGUACAAAC) (R1) having the sequence corresponding to the self-cleavage domain in a precursor RNA molecule from bacteriophage T4 infected Escherichia coli cells (p2Sp1 RNA). We synthesized an oligoribonucleotide (CAAACGUACAAAC) (R3) which contained the sequence (CGUACA) proposed for the p2Sp1 RNA self-cleavage site but did not form the hairpin loop structure. The self-cleavage ability of the single stranded RNA (R3) is significantly lower than that of R1. We have also designed a modified RNA fragment (R2), which contained a noncleavable RNA with 2'-O-methylcytidine or 2-O-methyluridine. R3 did not exhibit cleavage. To further investigate the structural requirements in the cleavage reaction, we synthesized mutant RNAs which contained different bases within consensus sequences and the cleavage sites were tested for self-cleavage. Guanosine and adenosine 3'-phosphates seemed not to be susceptible to transesterification at the cleavage site. The data from native gel electrophoresis, the CD spectra and the Tm suggested that the hairpin structure is necessary for the cleavage.

Bacteriophage T4↗
PubMed1994

Molecular recognition of the identity-determinant set of isoleucine transfer RNA from Escherichia coli.

Molecular recognition of Escherichia coli tRNA(Ile) by the cognate isoleucyl-tRNA synthetase (IleRS) was studied by analyses of chemical footprinting with N-nitroso-N-ethylurea and aminoacylation kinetics of variant tRNA(Ile) transcripts prepared with bacteriophage T7 RNA polymerase. IleRS binds to the acceptor, dihydrouridine (D), and anticodon stems as well as to the anticodon loop. The "complete set" of determinants for the tRNA(Ile) identity consists of most of the nucleotides in the anticodon loop (G34, A35, U36, t6A37 and A38), the discriminator nucleotide (A73), and the base-pairs in the middle of the anticodon, D and acceptor stems (C29.G41, U12.A23 and C4.G69, respectively). As for the tertiary base-pairs, two are indispensable for the isoleucylation activity, whereas the others are dispensable. Correspondingly, some of the phosphate groups of these dispensable tertiary base-pair residues were shown to be exposed to N-nitroso-N-ethylurea when tRNA(Ile) was bound with IleRS. Furthermore, deletion of the T psi C-arm only slightly impaired the tRNA(Ile) activity. Thus, it is proposed that the recognition by IleRS of all the widely distributed identity determinants is coupled with a global conformational change that involves the loosening of a particular set of tertiary base-pairs of tRNA(Ile).

Anticodon↗
PubMed1994

Continuous infusion versus intermittent short infusion of metoclopramide for cisplatin-induced acute emesis.

Metoclopramide is an active antiemetic against cisplatin-induced acute emesis. However, the optimal administration method (continuous infusion versus intermittent short infusion) for metoclopramide has not yet been clearly defined. We have conducted a randomized crossover study to compare the antiemetic efficacy of continuous infusion of metoclopramide with that of intermittent short infusion of metoclopramide in 54 evaluable patients. Patients were stratified according to sex and were randomized to receive either a continuous-infusion regimen (regimen A) or an intermittent-short infusion regimen (regimen B). Patients were switched to the alternate therapy in the second course. In regimen A, metoclopramide at 3 mg/kg i.v. was given before cisplatin, and then metoclopramide at 4 mg/kg was infused intravenously over 7.5 hours. In regimen B, metoclopramide at 3 mg/kg i.v. was followed by 2 mg/kg i.v. for two doses. Dexamethasone and diphenhydramine were given intravenously in both regimens. There was no significant difference between two regimens in their ability to prevent emesis. Complete protection (no episode of emesis) and major protection (< or = 2 episodes of emesis), respectively, were obtained by 67% (95% confidence interval: 53-79%) and 85% (95% confidence interval: 73-93%) of all patients given regimen A and by 59% (95% confidence interval: 45-72%) and 81% (95% confidence interval: 68-91%) of those given regimen B. The two regimens were also equally effective in controlling nausea. However, male patients showed better control of nausea and vomiting than did female patients, regardless of treatment regimen. Toxicity was mild in both regimens and was well tolerated. Our findings indicate that both continuous-infusion metoclopramide and intermittent-short infusion metoclopramide are effective in controlling cisplatin-induced acute nausea and vomiting.

Acute Disease↗
PubMed1994

Regulated expression of an osteonectin variant in bovine aortic endothelial cells.

Using a mouse SPARC (Secreted Protein, Acidic and Rich in Cysteine) cDNA clone as the probe, three clones were isolated from a cDNA library of bovine aortic endothelial cells (BAEC). Inserted sequences in them were identical with that of bovine bone osteonectin except for the deletion of the TGC codon encoding Cys-193. Northern blot analysis and metabolic radio-labeling of BAEC showed that gene expression and synthesis of the osteonectin variant is stimulated by transforming growth factor (TGF) beta, a basic fibroblast growth factor (FGF), or a naturally occurring splicing variant of hepatocyte growth factor (varHGF).

Animals↗
PubMed1994

[Paraplegia in flexion and dementia].

The purpose of this study was to assess possible correlations between paraplegia in flexion and dementia in elderly patients in our special nursing home and geriatric hospital. At the time of our study, 10.5% of all our patients were suffering from paraplegia in flexion, with the ratio increasing with advancing age. Disorders of the nervous system, and in particular disorders caused by cerebrovascular disease were found at a high rate of frequency among the paraplegia in flexion patients, in whom the incidence of dementia was 97.8%. In most cases, the degree of dementia was severe, the types and respective percentages being as follows: vascular type 37.8%, Alzheimer's type 24.4%, mixed type 22.2% and others 15.6%. Many of these patients demonstrated pseudobulbar palsy, frontal sign, Babinski's sign, and typical reflexes of spinal automatism. We think that paraplegia in flexion is probably caused by reflexes of spinal automatism and extensive cerebral lesions.

Aged↗
PubMed1994

[Disseminated intravascular coagulation (DIC) and pre-DIC due to severe infection in the elderly].

Because of pre-thrombotic state frequently present in the elderly, sepsis easily progresses to pre-DIC and DIC, sometimes with a fatal outcome. We assessed 31 elderly patients who developed pre-DIC and DIC due to severe infection. They were divided into two groups, early death group: 14 elderly patients with poor prognosis died within 14 days, and long survival group: 17 patients with good prognosis lived 15 days or more. Controls consisted of 31 elderly thrombotic disease cases and 25 healthy elderly cases. The DIC score was significantly higher in the early death group than in the long survival group, and there was a correlation between DIC score and survival. Moreover, many of the early death group were long-termed bed-ridden patients, serum BUN and Cre levels were significantly increased in the early death group compared to the long survival group. While plasma TAT, PIC and D-dimer levels were increased in thrombotic disease group compared to the healthy control group, TAT and D-dimer were also increased in the pre-DIC and DIC state than in the thrombotic state. In the early death group, D-dimer was higher than in the long survival group. We suggest that early diagnosis by molecular marker is important in the DIC stage, and a high D-dimer level may be a poor prognostic factor.

Aged↗
PubMed1994

[Role of institutions for the elderly in senile dementia].

The purpose of this study was to assess the role of institutions for the elderly, and special nursing homes in particular, with regard to senile dementia. The subjects consisted of 81 cases who were institutionalized in our special nursing home from early November, 1992 to late October, 1993. Of these, 37 cases (45.7%) showed clinical dementia at the time of institutionalization. The severity and respective percentages of dementia were as follows: slight degree 32.4%, moderate degree 27.0% and severe degree 40.6%. The severity of dementia demonstrated significant correlation with age. Hasegawa's Dementia Scale, activity of daily living and physical conditions. The admission rate (40.5%) of the demented group for physical diseases was significantly higher than that (22.7%) of the non-demented group. The majority of families of both groups first sought advice at institutions other than our special nursing home and the welfare office in the city, prior to being institutionalized. The referral rate from such institutions was far higher than that for direct entry from their homes. We consider that special nursing homes, in addition to carrying for daily living requirements, should pay great attention to physical diseases in patients suffering from senile dementia, and cooperate with medical institutes, particularly referring hospitals, and other welfare and health facilities, in this regard.

Activities of Daily Living↗
PubMed1994

[Anemia and neutropenia in elderly patients caused by copper deficiency for long-term enteral nutrition].

Anemia and neutropenia caused by copper deficiency is a well-known consequence of long term total parenteral nutrition in the literature. We present 6 bed-ridden elderly patients who developed anemia and neutropenia after receiving enteral nutrition for a long time (mean: 3.3 years) In all 6 patients, serum copper and ceruloplasmin level were very low, and the mean of their hematological data were as follows: WBC 2,200/microliters, neutrophil 554/microliters, hemoglobin 8.1 g/dl, platelet 260 x 10(3)/microliters, respectively. The bone marrow examination showed cytoplasmic vacuolization of both myeloid and erythroid precursors, and maturation arrest of granulopoiesis. Then, copper sulfate was administrated by enteral tube to 6 patients, and the improvement of anemia and neutropenia was observed within a month. A 82-year-old woman who received enteral nutrition for 3.5 years with sever anemia (Hb 3.7 g/dl) and neutropenia (neutrophil 350/microliters), showed a marked improvement in hematological data (Hb 8.0 g/dl, neutrophil 4, 092/microliters, respectively) after two months by administering the copper supplementation. The exact cause of the anemia and neutropenia in copper deficiency is unclear, but it is suggested that the decreased activity of enzyme containing copper may be related. Hematological abnormalities due to copper deficiency should be cared during long term enteral nutrition with long termed bed-ridden elderly patients.

Aged↗
PubMed1993

A modified uridine in the first position of the anticodon of a minor species of arginine tRNA, the argU gene product, from Escherichia coli.

The argU (dnaY) gene product, a minor tRNA(Arg), from Escherichia coli has the anticodon N*CU with an unidentified modified nucleoside N* in position 34 [Kiesewetter, S., Fisher, W. & Sprinzl, M. (1987) Nucleic Acids Res. 15, 3184]. In the present study, argU tRNA was purified from E. coli A19 strain and nucleoside N* was characterized by the TLC and HPLC analyses. Nucleoside N* was found to be different from any naturally occurring modified nucleosides. From unfractionated E. coli tRNA species, nucleoside N* was prepared in an amount sufficient for 1H-NMR experiments. By the analyses of one-dimensional and two-dimensional NMR spectra, nucleoside N* was suggested to be 5-methylaminomethyluridine (mnm5U), which was confirmed by comparison with a chemically synthesized preparation of mnm5U. Thus, the occurrence of mnm5U in mature tRNA was found for the first time. Further, the modification of U(34) to mnm5U in this tRNA was found to contribute to the strict recognition of two degenerate codons terminating in A and G.

Anticodon↗
PubMed1993

A cold-inducible Bombyx gene encoding a protein similar to mammalian sorbitol dehydrogenase. Yolk nuclei-dependent gene expression in diapause eggs.

To facilitate the study of the induction of sorbitol dehydrogenase by acclimation to 5 degrees C in diapause eggs of the silkworm, Bombyx mori, two cDNA libraries from eggs and larval fat bodies were screened with anti-(sorbitol dehydrogenase) serum, and a positive cDNA was cloned from the fat-body cDNA library. 1039 nucleotides determined from the cDNA corresponded to a protein-coding region consisting of 346 amino acids. The missing regions (containing two amino acids at the 5' end and a stop codon at the 3' end) were supplemented with the genome sequence. The deduced amino-acid sequence had 45-47% identity with mammalian sorbitol dehydrogenases. The results led us to conclude that the cDNA for a Bombyx homolog of mammalian sorbitol dehydrogenase was isolated, which was designated as BmSDH. Analyses of Northern hybridization and reverse transcription/polymerase chain reaction showed that the transcript of BmSDH occurred after chilling for 40-50 days when the diapause eggs were exposed to 5 degrees C from two days after oviposition to break the diapause. The changing pattern in the amount of BmSDH transcript was well correlated with those in the activity of sorbitol dehydrogenase and the amount of the enzyme protein in diapause eggs. Further, the transcript of BmSDH was localized in yolk cells. The results indicate that the yolk nuclei-dependent gene expression of BmSDH is induced by acclimation to 5 degrees C in diapause eggs.

Amino Acid Sequence↗
PubMed1993

Prognostic significance of p53 mutations and 3p deletions in primary resected non-small cell lung cancer.

We evaluated the prognostic significance of p53 mutations and an allelic loss of chromosome 3p in 71 patients with non-small cell lung cancer who underwent potentially curative resection. p53 mutations were detected in 35 cases (49%), while 3p deletions were observed in 34 of 70 informative cases (49%). The presence of the p53 mutation was associated with a shortened survival in all patients (P = 0.014 by log rank test), including those in early stages of the disease (stage I or II, n = 48) (P = 0.016 by log rank test). Multivariate analysis by the Cox proportional hazards model also revealed that p53 mutation was an independent yet unfavorable prognostic factor (P = 0.013). Patients with 3p deletion tended to have a poorer prognosis, but not to a statistically significant extent.

Aged↗
PubMed1993

A 15N-1H nuclear magnetic resonance study on the interaction between isoleucine tRNA and isoleucyl-tRNA synthetase from Escherichia coli.

Imino 15N and 1H resonances of Escherichia coli tRNA(lIle) were observed in the absence and presence of E coli isoleucyl-tRNA synthetase. Upon complex formation of tRNA(lIle) with isoleucyl-tRNA synthetase, some imino 15N-1H resonances disappeared, and some others were significantly broadened and/or shifted in the 1H chemical shift, while the others were observed at the same 15N-1H chemical shifts. It was indicated that the binding of tRNA(lIle) with IleRS affect the following four regions: the anticodon stem, the junction of the acceptor and T stems, the middle of the D stem, and the region where the tertiary base pair connects the T, D, and extra loops. This result is consistent with those of chemical footprinting and site-directed mutagenesis studies. Taken together, these three independent results reveal the recognition mechanism of tRNA(lIle) by IleRS: IleRS recognizes all the identity determinants distributed throughout the tRNA(lIle) molecule, which induces changes in the secondary and tertiary structures of tRNA(lIle).

Base Sequence↗
PubMed1993

Developmental profile of the gene expression of a Bombyx homolog of mammalian sorbitol dehydrogenase during embryogenesis in non-diapause eggs.

1. By using semi-quantitative PCR analysis, changes in the amount of the transcript for a Bombyx homolog of mammalian sorbitol dehydrogenase (BmSDH) were examined during embryogenesis in non-diapause eggs. 2. Occurrence of the transcript for BmSDH correlated with the two developmental phases, the growth of embryo and the formation of larval tissues. 3. In the first phase, an increase in the amount of the transcript for BmSDH resulted from embryonic cells rather than yolk cells. 4. In the second phase, the transcript was suggested to be abundant in fat-body cells of pharate larva, because it was abundant in fat-bodies of 5th instar larvae. 5. The difference in the expression of BmSDH gene between diapause and non-diapause eggs is discussed.

Animals↗
PubMed1993

[Non-Hodgkin's lymphoma with pulmonary involvement and various immunological abnormalities in an elderly patient].

A 85-year-old female was admitted with general fatigue and chest discomfort in July 1991. Her chest X-ray film showed several pulmonary nodules in the bilateral lung fields without hilar lymphadenopathy. Metastatic lung cancer was suspected, but primary cancer was not detected in spite of cancer screening. Hemoglobin was 8.7 g/dl. The patient also had various immunological abnormalities including increased serum cold agglutinin titer, decreased serum complement, positive anti-nuclear antigen and IgM-kappa monoclonal gammopathy detected by immunoelectrophoresis. She was diagnosed as having autoimmune hemolytic anemia with cold agglutinin disease and M-protein. With the administration of corticosteroids, hemolytic anemia improved temporarily, but the patient died of hemorrhagic gastritis. At autopsy, a lung tumor was detected in the left upper lobe, mainly without hilar lymphadenopathy. The autopsy specimens showed Non-Hodgkin's lymphoma (diffuse medium-sized cell type), differentiated from macroglobulinemia by immunohistochemical studies. In elderly patients, with various immunological abnormalities, B-cell lymphoproliferative disorders such as malignant lymphoma should be suspected.

Aged↗
PubMed1993

[Comprehensive functional assessment of the elderly in institutions, particularly in terms of social life].

The purpose of this study was to clarify aspects of social life in a comprehensive functional assessment of 160 elderly subjects, over 60 years of age, in institutions for the elderly. Five items were assessed: economic conditions, marital status, family conditions, family relationships and group behavior. The institutions were of 4 types: a geriatric hospital, a special nursing home for the aged, a home for the elderly and a home with moderate fees. The assessment of social life demonstrated significant correlation between the revised version of Hasegawa's Dementia Scale, activity of daily living and physical conditions. Inter-institution comparisons revealed significant differences in terms of economic conditions for the home for the elderly, family conditions for the home with moderate fees, and family relationships and group behavior for the geriatric hospital. Total grades across the 5 items were significantly lower for the geriatric hospital cases. This assessment proved useful to illuminate aspects of social life of the elderly in institutions.

Activities of Daily Living↗
PubMed1993

[Successful treatment with cisplatin-based chemotherapy and post-chemotherapy operation for mediastinal nonseminomatous germ cell tumor with pulmonary metastasis].

In October 1988, a 19-year-old man was admitted with complaint of chest pain. Chest X-ray film and CT scan of the chest revealed a large mediastinal mass and several bilateral pulmonary nodules. Serum hCG and alpha-fetoprotein levels were 5096.0 mIU/ml (normal < 2.0) and 2176.9 ng/ml (normal < 10), respectively. Percutaneous needle biopsy of the mediastinal tumor disclosed an immature teratoma. The patient had normal testes on physical examination. CT scans of the brain and abdomen, and radioisotope scanning of the bones showed no abnormality. He was diagnosed as having a primary mediastinal nonseminomatous germ cell tumor (mixed cellular type) with pulmonary metastasis. On October 31, induction chemotherapy was started with PVB regimen: cisplatin 20 mg/m2 administered intravenously (i.v.) on days 1 through 5 every three week (three courses), vinblastine 0.15 mg/kg i.v. on days 1 and 2 every three weeks (three courses), and bleomycin 30 mg administered by i.v. push (starting on day 7) weekly x 9. Following the chemotherapy, serum alpha-fetoprotein fell to the normal range. Serum hCG decreased rapidly but did not reach the normal range. On January 7, 1989, en bloc resection of the residual primary tumor was performed which involved partial pericardiectomy and wedge resection of the left upper lobe. Four residual pulmonary nodules were also removed. Histologically, the surgical specimen was composed of fibrous, necrotic tissue mainly and immature teratoma partially.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗