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T Kurihara

Publications and source records attributed to T Kurihara.

At least 199 records · Page 11Linked to original sources
PubMed1993

Suppression of a sec63 mutation identifies a novel component of the yeast endoplasmic reticulum translocation apparatus.

Mutations in the SEC63 gene are associated with defects in protein translocation into the endoplasmic reticulum (ER) as well as in nuclear protein localization in Saccharomyces cerevisiae. To identify proteins that might interact and/or function with SEC63p, we cloned a high copy suppressor (HSS1) of the temperature-sensitive lethal phenotype of the sec63-101 mutant. HSS1 is an allele-specific sec63 suppressor that encodes an integral ER membrane glycoprotein of 206 amino acids with the N-terminus in the ER lumen and C-terminal region in the cytoplasm. Haploid strains disrupted for HSS1 are temperature-sensitive for growth and accumulate precursor forms of Kar2p and invertase. The HSS1 null allele is synthetically lethal in combination with mutations affecting ER translocation. We propose that HSS1p is important for ER translocation and interacts with previously identified components of the yeast translocation apparatus. HSS1 is identical to SEC66, which encodes a glycoprotein complexed with SEC62p and SEC63p.

Alleles↗
PubMed1993

Extragenic suppressors of mutations in the cytoplasmic C terminus of SEC63 define five genes in Saccharomyces cerevisiae.

Mutations in the SEC63 gene of Saccharomyces cerevisiae affect both nuclear protein localization and translocation of proteins into the endoplasmic reticulum. We now report the isolation of suppressors of sec63-101 (formerly npl1-1), a temperature-sensitive allele of SEC63. Five complementation groups of extragenic mutations, son1-son5 (suppressor of npl1-1), were identified among the recessive suppressors. The son mutations are specific to SEC63, are not bypass suppressors, and are not new alleles of previously identified secretory (SEC61, SEC62, KAR2) or nuclear protein localization genes (NPL3, NPL4, NPL6). son1 mutations show regional specificity of suppression of sec63 alleles. At low temperatures, son1 mutants grow slowly and show partial mislocalization of nuclear antigens. The SON1 gene maps to chromosome IV and encodes a nuclear protein of 531 amino acids that contains two acidic stretches and a putative nuclear localization sequence. We show that son1 mutations suppress sec63-101 by elimination of Son1p function.

Alleles↗
PubMed1993

Ear-piercing technique by using an eyelet-type Teflon piercer (Eyelet-Piercer).

We devised a new method of piercing earlobes. This method, in which an eyelet-shaped Teflon tube (Eyelet-Piercer) is left in the earlobe continuously, is advantageous in that any type of pierced earrings the subject wishes can be used immediately after treatment and in that subjects with metal allergies can safely use pierced earrings. In addition, the incidence of complication was lower with this technique than with conventional methods that use metal earrings for piercing.

Ear, External↗
PubMed1993

Muscarinic excitatory and inhibitory mechanisms involved in afferent fibre-evoked depolarization of motoneurones in the neonatal rat spinal cord.

1. The involvement of acetylcholine and muscarinic receptors in spinal synaptic responses evoked by electrical and noxious sensory stimuli was investigated in the neonatal rat spinal cord in vitro. 2. Potentials were recorded extracellularly from a ventral root (L3-L5) of the isolated spinal cord, spinal cord-cutaneous nerve, and spinal cord-skin preparations of 1- to 4-day-old rats. Spinal reflexes were elicited by electrical stimulation of the ipsilateral dorsal root or the cutaneous saphenous nerve, or by noxious skin stimulation. 3. Single shock stimulation of supramaximum intensity of a dorsal root induced a mono-synaptic reflex in the corresponding ventral root. Bath-application of the muscarinic agonists, muscarine (0.3-30 microM) and (+)-cis-dioxolane (0.1-100 microM), produced an inhibition of the mono-synaptic reflex and a depolarization of motoneurones. Other muscarinic agonists, arecoline (10 nM-10 microM) and oxotremorine (10 nM-1 microM), inhibited the mono-synaptic reflex with little or no depolarization of motoneurones. Repetitive stimulation of the saphenous nerve at C-fibre strength induced a slow depolarizing response lasting about 30 s of the L3 ventral root. This slow ventral root potential (VRP) was also inhibited by arecoline (10 nM-10 microM) and oxotremorine (10 nM-1 microM). 4. In the spinal cord-saphenous nerve-skin preparation, a slow VRP was evoked by application of capsaicin (0.5 microM), bradykinin (3 microM), or noxious heat (47 degrees C) to skin. This slow VRP was depressed by the muscarinic agonists, arecoline (3 microM) and oxotremorine (1 microM). 5. Of the (+)-cis-dioxolane-induced inhibition of mono-synaptic reflex and motoneurone depolarization, the M2 antagonists, AF-DX 116 (0.1-1 microM) and methoctramine (100-300 nM), preferentially blocked the former response, whereas the M3 antagonists, 4-DAMP (3-10 nM) and p-F-HHSiD (0.3-3 microM), preferentially blocked the latter response. AF-DX 116 (0.1-1 microM) and methoctramine (100-300 nM) also effectively antagonized the arecoline- and oxotremorine-induced inhibition of the slow VRP. The pA2 values of AF-DX 116 and methoctramine against the arecoline-induced inhibition of the mono-synaptic reflex were both 6.79, and that of 4-DAMP against the (+)-cis-dioxolane-induced motoneurone depolarization was 8.16. 6. In the spinal cord-cutaneous nerve preparation, the saphenous nerve-evoked slow VRP was augmented by the anticholinesterase, edrophonium (5 microM). AF-DX 116 (1 microM) and methoctramine (100 nM) also potentiated the slow VRP, whereas 4-DAMP (10 nM) depressed the response. 4-DAMP(5-10 nM) depressed the capsaicin-induced slow VRP in the spinal cord-skin preparation.7. Oxotremorine (0.3 microM) and arecoline (1 AM) markedly depressed the depolarization of motoneurones evoked by application of capsaicin (3 9AM) to the spinal cord, whereas they depressed only slightly the depolarization induced by substance P (10 nM).8. The present study suggests that both excitatory (via M3-type receptors) and inhibitory (via M2-type receptors) muscarinic mechanisms are involved in afferent fibre-evoked nociceptive transmissions in the neonatal rat spinal cord.

Animals↗
PubMed1993

Diagnostic radioimmunoassay and DNA-analysis in Swedish and Japanese patients with familial amyloidotic polyneuropathy. Homozygosity for the TTR met30 gene.

Eighteen Swedish patients with familial amyloidotic polyneuropathy were tested for the met30 mutation of the transthyretin (TTR) (prealbumin) gene by RFLP analysis of genomic DNA using the restriction enzyme NsiI. The results confirmed previous findings that the Swedish variant of familial polyneuropathy has the same valine by methionine substitution at position 30, as seen in patients with FAP from Japan, Portugal or patients of Swedish descent from USA. However, two of the patients were homozygous, totally lacking the wild type allele. Measurable serum values for the variant transthyretin (TTR) was detected with a RIA-method in all the 18 Swedish FAP patients studied with a mean concentration of 12.1 +/- 5.1 (SD) mg/100 ml, (11.0 +/- 4.1 when the two homozygotes were excluded). In 45 Japanese patients the mean was 9.2 +/- 2.7 mg/100 ml. The variant TTR was not detected in the healthy controls. The value for the variant TTR was nearly twice that high in the two homozygous patients, 21.14 and 21.16 mg/100 ml, respectively. There was no correlation between the serum levels of variant TTR and the duration of disease or levels of serum albumin in the FAP-patients.

Adolescent↗
PubMed1993

[In vitro induction of chlorhexidine- and benzalkonium-resistance in clinically isolated Pseudomonas aeruginosa].

A study was made on the MIC distributions of chlorhexidine and benzalkonium chloride against clinically isolated 178 strains of Pseudomonas aeruginosa to find out the existence of strains resistant to those disinfectants and also on the in vitro induction of resistance to both drugs. The MIC of chlorhexidine gluconate was found to be distributed from 78 to 625 micrograms/ml with a single peak at 312 micrograms/ml. All 178 strains of clinical isolates were sensitive to chlorhexidine and none could be induced to become chlorhexidine resistant in vitro, suggesting that P. aeruginosa can not easily acquire chlorhexidine resistance. On the other hand, the MIC of benzalkonium chloride was distributed in two peaks; one peak was benzalkonium sensitive at 625 micrograms/ml (150 strains/178 strains: 84.3%) and the another peak was benzalkonium resistant at 5,000 micrograms/ml (28 strains/178 strains; 15.7%). Six (4.0%) of the 150 benzalkonium sensitive strains acquired benzalkonium resistance by in vitro induction of resistance; the MIC of 5 strains increased from 625 micrograms/ml to 2,500 micrograms/ml and that of the residual 1 strain increased from 312 micrograms/ml to 1,250 micrograms/ml. However, no change of MIC was observed in 28 benzalkonium-resistant strains of clinically isolated P. aeruginosa by in vitro resistance induction. Strains with MIC more than 5,000 micrograms/ml could not be obtained at all. The results suggest that the benzalkonium resistance can be introduced in P. aeruginosa whereas the resistance-acquiring rate is low. These results suggest that chlorhexidine gluconate is the first choice for prevention of Pseudomonas infection in the hospital and benzalkonium is also useful in 0.5% solution is used.

Aerosols↗
PubMed1993

Early hepatic lesions with marked glandular structures induced in rats by 0.1% ethionine in a choline deficient diet.

Early hepatic lesions in rats fed ethionine plus a choline deficient (ECD) diet were examined histopathologically. The purpose of this experiment was to examine preventive and suppressive effects of drugs on fatty or cirrhotic liver induced by ECD, but contrary to our expectations, all groups except the normal diet group showed neoplastic lesions in the liver. Macroscopically, milky-white nodules were seen in most all the rats except for a few dead ones. Microscopically, the characteristic lesions consisted of neoplastic nodules, glandular structures and oval cell hyperplasia. The glandular structures were already present in a rat that died on day 34 of administration and showed neoplastic developmental structures morphologically similar to cholangiofibroma. The neoplastic nodules appeared later than the glandules and were observed in rats that died after day 42. To the best of our knowledge, this is the first report of hepatic lesions consisting of mainly glandular structures induced by an ECD diet.

Animals↗
PubMed1993

Concept of simulation surgery.

The concept of simulation surgery was first proposed by Fujino in 1989 and reinforced in 1991. It is divided in two sections; empirical simulation surgery, where the surgical procedure is designed first in the surgeon's brain, and computer simulation surgery, where the disease condition and the possible surgical procedures can be viewed in three-dimensions (3D) either on a computer monitor, or by means of a solid 3D model, crafted from computer generated data, before proceeding to the actual surgery itself. Each of these sections is subdivided into three subsections; morphological, functional and psychological simulation surgery, respectively. Along those lines, the concept of simulation surgery is discussed, with special reference to plastic and reconstructive surgery.

Computer Simulation↗
PubMed1993

[Relationship of left ventricular wall motion to myocardial viability in patients with recent myocardial infarction].

The influence of left ventricular myocardial perfusion on left ventricular wall motion in patients with recent myocardial infarction was studied to try to differentiate viable myocardium from necrotic myocardium in 21 patients with initial myocardial infarction who received successful percutaneous transluminal coronary angioplasty (PTCA) 5-8 weeks after the onset. Exercise stress myocardial tomography with 201Tl (Ex-Tl) was performed before (3-5 weeks after acute onset) and after PTCA. Myocardial images were reconstructed into a bull's eye map which was divided into 17 segments. Rest ECG-gated cardiac blood pool tomography with 99mTc was performed before PTCA, and the left ventricular wall was divided into the same 17 segments used in Ex-Tl. The % shortening in each segment was calculated. Myocardial perfusion and % shortening were compared in each myocardial segment. Myocardial perfusion was classified into 4 types by considering whether exercise induced myocardial perfusion abnormality was transient (RD(+)) or persistent (RD(-)) in delayed image; 1) normal perfusion, 2) redistribution (+); RD(+): transient or viability exercise-induced perfusion defect before PTCA, 3) RD(-)/viable: fixed defect before PTCA but normal perfusion after PTCA, and 4) necrosis: fixed defect before and after PTCA. Most normal perfusion segments (88% of 184) showed normal wall motion and mean % shortening was 42 +/- 11%. Only 13 of 73 RD(+) segments showed normal wall motion. Thirty-eight and 19 RD(+) segments showed moderate hypokinesis and severe hypokinesis or akinesis, respectively. Mean % shortening in RD(+) segments was 19 +/- 13%. Thirty-seven of 38 RD(-)/viable segments had wall motion abnormalities, and 20 showed severe hypokinesis or akinesis. Mean % shortening in RD(-) segments was 12 +/- 8%. All 62 necrosis segments showed wall motion abnormalities including 10 with dyskinesis and 42 with akinesis or severe hypokinesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

[Assessment of myocardial viability by exercise stress-redistribution myocardial scintigraphy with thallium-201: the usefulness of C-map].

Standard exercise (Ex)-redistribution (RD) myocardial imaging with thallium-201 (201Tl) may not differentiate viable myocardium from necrosis. This study was intended to clarify whether 201Tl washout rate (WOR) abnormality after Ex can detect myocardial viability in the myocardium with perfusion defect using routine RD image. We performed Ex-RD (three hours after) myocardial tomography with 201Tl in 29 patients with coronary artery disease. From myocardial tomography, 201Tl distribution Bull's-eye maps (Ex and RD) and WOR Bull's-eye map were made. At RD image before PTCA, by referring to the original image, the activity of the myocardial region below 40% to 55% of the maximal 201Tl activity was considered as perfusion defect (RD-Map). Then we constructed a new image (C-Map) by adding the location of WOR abnormality (< or = 30%) to the RD-Map and each map was divided into 17 segments. If the defect-segment in the RD-Map corresponded to WOR abnormality, the segment in the C-Map was judged as viable (no defect). The C-Map and myocardial imaging after PTCA (Post-Map) were compared. In the RD-Map before PTCA, defect was found in 152 segments but in the C-Map they decreased to 59 segments, while defect was found in 62 segments in the Post-Map. In 23 patients the number of defect-segments in the C-Map decreased as compared with those in the RD-Map. And in 22 of them, the Post-Map showed the reduction of defect-segments in comparison with the RD-Map, but in one of them defect did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

[A case of myasthenia gravis associated with multiple sclerosis and positive anticardiolipin antibodies].

A 42-year-old housewife with myasthenia gravis (MG) for 22 years, who was initially treated by radiation to the hyperplastic thymus and anti-cholinesterase therapy, developed bilateral ptosis, paresthesia of her right face and decreased taste sensation after house work at the age of 42 years. Neurological examinations revealed lateral and vertical gaze palsy, upward nystagmus, decreased taste sensation, peripheral facial palsy on the left side. She also had hypalgesia on the right face, arm and chest up to Th7 level, and urinary retention. She had hyperreflexia on the right side but no extensor toe signs. CSF study revealed 5 cells/microliters and protein of 23 mg/dl. Serum IgG anticardiolipin antibody was positive. Magnetic resonance imaging studies revealed high intensity areas in the brainstem tegmentum and periventricular white matter. Diagnosis of multiple sclerosis (MS) was made. This is the first case in which MG, MS and serum anticardiolipin antibody were present simultaneously, which may be all due to some immunological abnormality. Steroid therapy made anti-cardiolipin antibody negative, but new MS plaque developed in 7 months, which favors diagnosis of MS rather than infarction, since the activities of ACLA were not correlating to clinical symptoms. MRI was helpful in detecting MS plaques in MG patients.

Adult↗
PubMed1993

[Nuclear DNA content in breast carcinoma by fine needle aspiration biopsy].

The usefulness of the measurement of nuclear DNA content by fine needle aspiration biopsy was evaluated through a comparative study of fine needle aspirated and tissue samples. Nuclear DNA content was measured in patients with 28 primary and 2 metastatic lesions of breast carcinoma using fluorescent cytophotometry with Feulgen stain. The rate of correspondence on DNA ploidy pattern of aspirates and tissue samples was 86.7%. There was a significant correlation with DNA index (DI) (R = 0.85, p < 0.001) and S-phase fraction (%S) (R = 0.79, p < 0.001). The rate of correspondence of DI subgroups (3 aneuploid subgroups and diploid) was 80.8%. No tumor size affected values of DI and %S of aspirates. However, %S of papillotubular carcinoma showed small difference compared with values of tissue samples. Nuclear DNA content of fine needle aspirated samples had a significant correlation with that of tissue samples, providing the estimation of the original ploidy pattern and DI. Fine needle aspiration biopsy is an easy technique and able to be carried out repeatedly. Thus, the measurement of nuclear DNA content using aspirates is useful for broad practical purposes.

Adenocarcinoma↗
PubMed1993

[Cytotoxic effects of diclofenac sodium].

The authors studied the cytotoxic effect of diclofenac sodium, a prostaglandin synthetic inhibitor, on Chang's cultured human conjunctival cells. Diclofenac sodium inhibited cell growth dose-dependently. Although cell growth was interrupted 12 hrs later by one minute of exposure to a 0.1% solution of diclofenac sodium, the cells began to grow again 24 hrs later. Twenty-four hours later, a one-minute exposure to a 0.1% solution of diclofenac sodium revealed no cytotoxic effects electron microscopically. The effect on the cell cycle of exposure to 0.1% diclofenac sodium was studied using a flow cytometer. Twelve hours after exposure to diclofenac sodium, DNA histograms showed a broader G1 peak, and increase in mitotic phase cells and dead cells with a low DNA content on the left of the G1 peak. 24 hrs later, the number of dead cells and DNA synthetic phase cells increased and mitotic cells gradually decreased, almost disappearing within 48 hrs.

Cells, Cultured↗
PubMed1993

[Usefulness of contact thermography for the evaluation of chemotherapeutic effectiveness in breast cancer].

We examined temperature differences between a cancerous breast and its counterpart normal one by contact thermography before and after preoperative chemotherapy, and evaluated the relationship between the changes in the thermograms and response to chemotherapy in six patients with breast cancer. We used the following definitions: 1) delta Tmean: temperature differences between a mean temperature of a cancerous breast and that of the contralateral healthy breast; 2) delta Tmax: temperature differences between a cancer-related hyperthermic area in a breast and the mirror area of contralateral breast; 3) and the thermal patterns in thermogram were estimated by the criteria of Tada et al. In responders the thermograms after chemotherapy indicated an improvement in the hyperthermic vascular pattern (HVP) or hyperthermic area and a decrease of delta Tmean and delta Tmax. In contrast, little or no changes were observed in the thermograms of non-responders. Degrees of changes in thermograms reflected the effectiveness of chemotherapy. Our study showed that chemotherapeutic effectiveness may be better evaluated by combining contact thermography with the present method measuring tumor sizes than by only the present one.

Adult↗
PubMed1992

Peroxisomal acetoacetyl-CoA thiolase of an n-alkane-utilizing yeast, Candida tropicalis.

Two genes encoding acetoacetyl-CoA thiolase (thiolase I; EC 2.3.1.9), whose localization in peroxisomes was first found with an n-alkane-utilizing yeast, Candida tropicalis, were isolated from the lambda EMBL3 genomic DNA library prepared from the yeast genomic DNA. Nucleotide sequence analysis revealed that both genes contained open reading frames of 1209 bp corresponding to 403 amino acid residues with methionine at the N-terminus, which were named as thiolase IA and thiolase IB. The calculated molecular masses were 41,898 Da for thiolase IA and 41,930 Da for thiolase IB. These values were in good agreement with the subunit mass of the enzyme purified from yeast peroxisomes (41 kDa). There was an extremely high similarity between these two genes (96% of nucleotides in the coding regions and 98% of amino acids deduced). From the amino acid sequence analysis of the purified peroxisomal enzyme, it was shown that thiolase IA and thiolase IB were expressed in peroxisomes at an almost equal level. Both showed similarity to other thiolases, especially to Saccharomyces uvarum cytosolic acetoacetyl-CoA thiolase (65% amino acids of thiolase IA and 64% of thiolase IB were identical with this thiolase). Considering the evolution of thiolases, the C. tropicalis thiolases and S. uvarum cytosolic acetoacetyl-CoA thiolase are supposed to have a common origin. It was noticeable that the carboxyl-terminal regions of thiolases IA and IB contained a putative peroxisomal targeting signal, -Ala-Lys-Leu-COOH, unlike those of other thiolases reported hitherto.

Acetyl-CoA C-Acetyltransferase↗
PubMed1992

Origin of brain 2',3'-cyclic-nucleotide 3'-phosphodiesterase doublet.

The present study established that 2',3'-cyclic-nucleotide 3'-phosphodiesterase doublet common to mammalian brain originates from an alternative splicing. Peptides specific to the predicted larger translation product were synthesized and antisera against these peptides were prepared. Immunostaining of SDS/PAGE blots showed that the antisera react with the larger protein, but not with the smaller protein, of 2',3'-cyclic-nucleotide 3'-phosphodiesterase doublet in all mammals studied.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗