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T Uozumi

Publications and source records attributed to T Uozumi.

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

Detection of potato virus Y P1 protein in infected cells and analysis of its cleavage site.

The P1 protein is liberated from the N-terminal region of the potyviral polyprotein by cleavage depending on its own autoproteolytic activity. Existence of the 32-kDa P1 protein in tobacco plants infected with potato virus Y ordinary strain (PVY-O) was detected by an antiserum against a recombinant PVY-O P1 protein. In vivo analysis using tobacco protoplasts confirmed that the Phe284-Ser285 was the cleavage site separating the P1 protein from the PVY-O polyprotein. Phe284 was indispensable for proteolysis and Ser285 was needed for optimal cleavage susceptibility.

Amino Acid Sequence↗
PubMed1998

Effects of successful adenomectomy on body composition in acromegaly.

The purpose of the present study was to investigate postsurgical change in body composition in patients who have undergone surgery for acromegaly. Eight patients with acromegaly had determination of serum GH, insulin-like growth factor-I (IGF-I), height, body weight, and bioelectric impedance before surgery and at 2 weeks, 1 month, 3 months, and 6 months after surgery. Body composition was analyzed by bioelectric impedance analysis (BIA). We analyzed body fat (BF), body lean mass (BLM), body cell mass (BCM), total body water (TBW), intracellular water (ICW) and extracellular water (ECW). The serum GH concentration and IGF-I had decreased significantly 2 weeks after surgery. Body weight had decreased significantly 1 month after surgery and recovered 3 months after surgery. BIA showed that TBW and BCM had decreased significantly 2 weeks after surgery. BF gradually increased up to 1 month after surgery and was increased significantly at 3 months after surgery. The percent ratio of TBW/body weight decreased and the percent ratio of BF/body weight increased during the 6 months after surgery. The percent ratio of ECW/TBW did not change during the 6 months following surgery. In conclusion, the rapid body weight loss which occurred within 2 weeks after surgery was caused by decreases in TBW and BCM. The recovery of body weight, which was seen later than 1 month after surgery, was caused by an increase in BF. The postoperative change in body composition in acromegaly ceased 3 months after surgery.

Acromegaly↗
PubMed1998

[Multivariate analysis of intentional temporary vessel occlusion in aneurysmal surgery].

Temporary vessel occlusion (TO) for aneurysmal clipping is an effective technique to facilitate dissection between aneurysm and parent vessels, and to place a permanent clip at the aneurysmal neck precisely. However, several unsolved problems remain regarding the overall safety and risk resulting from this technique. The authors examined a series of patients in whom mannitol 500 ml, tocopherol acetate 500 mg, and phenytoin 500 mg were administered intravenously as ischemic protection during TO for the aneurysmal clipping. The study comprises a nonconcurrent retrospective analysis of 144 consecutive aneurysm clippings performed with the aid of intentional TO at the Hiroshima Prefectural Hospital from 1985 to 1995. To identify technical and patient-specific risk factors for perioperative stroke, factors studied included duration, location of the temporary clip application, number of occlusive episodes, patient sex, age, and preoperative neurological status, timing of operation, as well as postoperative, temporary or permanent, neurological deficits (ND) due to TO were used. Overall frequency of postoperative ND due to TO manifested clinically and radiologically were 9.0% and 9.7%, respectively. In both univariate and multivariate analysis there were no significant factors relevant to the ND. However, duration of the temporary occlusion time over 20 minutes was the factor most influential on the ND due to TO. Duration of the temporary occlusion time was shown to have no link with outcome. Based on our findings the authors conclude that temporary vessel occlusion within 20 minutes with anti-ischemic drugs is a relatively safe adjunct to aneurysmal surgery.

Adult↗
PubMed1997

Regulation of cyclodextrin glucanotransferase synthesis in Bacillus ohbensis.

The production of cyclodextrin glucanotransferase (CGTase) by Bacillus ohbensis is dependent on the presence of starch and inhibited by glucose in the medium. Northern blot analysis revealed that the CGTase gene (cgt) was transcribed to almost the same level irrespective of the presence or absence of starch, but glucose completely repressed the transcription. Furthermore, a relatively high amount of CGTase protein was detected on Western blotting only in the medium with starch, showing the lack of posttranslational control of the CGTase activity. These findings suggest some starch induction mechanism for the cgt gene, possibly at the posttranscriptional level, besides negative transcriptional regulation by glucose.

Bacillus↗
PubMed1997

Cloning and sequencing of an alpha-glucosidase gene from Aspergillus niger and its expression in A. nidulans.

We have cloned an extracellular alpha-glucosidase gene from Aspergillus niger with oligonucleotide probes synthesized on the basis of the determined peptide sequences. The nucleotide sequence revealed an open reading frame of 985 amino acids split with three introns, and the deduced amino acid sequence was nearly identical to that of the alpha-glucosidase previously determined. The cloned gene was introduced into Aspergillus nidulans, and its expression in the transformants was shown to be regulated by the carbon sources in the medium, suggesting that a common regulatory expression system is shared by these two species as is the case of other starch-degrading enzymes of Aspergillus species.

Amino Acid Sequence↗
PubMed1997

Usefulness of two-dimensional time-of-flight MR angiography combined with surface anatomy scanning for convexity lesions.

Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions.

Adolescent↗
PubMed1997

Incidence of intracranial aneurysm associated with pituitary adenoma.

The incidence of intracranial aneurysm associated with pituitary adenoma is not definitely established although reported higher than in general population. This study was designed to find the existence of such association in a large series of pituitary adenoma cases. A retrospective study of 467 cases of pituitary adenoma (mean age: 41 +/- 15 years) was done. All patients underwent cerebral angiography at least of anterior circulation, detailed hormonal study, and 155 cases had additional magnetic resonance (MR) angiography. Twenty-five cases (5.4%) of pituitary adenoma (mean age 52 years) had intracranial aneurysm, 97% on anterior circulation, and 12% had multiple aneurysms. Two cases presented with aneurysmal rupture and the rest were incidental. Aneurysm was more frequently seen with increasing age (p < 0.001) and the age distribution resembled that of aneurysm among general population. Although the combination was most frequent among nonfunctioning adenoma (8.8%), and least frequent among prolactinoma (2.4%), this association was again due to age factor. There was no association between hormone secretion, size and invasive nature of the tumor. The results showed no association between intracranial aneurysm and pituitary adenoma. Our speculation is that such occurrence is merely a chance factor and the risk is no greater than that among general population.

Adenoma↗
PubMed1997

MIB1 immunopositivity is associated with rapid regrowth of pituitary adenomas.

Pituitary adenomas are generally regarded as benign tumours, but they may recur. We identified eight patients with pituitary adenomas that showed rapid regrowth within 2 years of initial surgery. We estimated the percentage of cells in each specimen that showed positive immunostaining for MIB1 (a novel anti-Ki-67) and compared the values to those of 40 adenomas that showed no regrowth. The mean MIB1 index for 40 adenomas that showed no evidence of regrowth was 0.19 +/- 0.06%. This was significantly (p < 0.0001) lower than that for adenomas that showed rapid regrowth (1.27 +/- 0.31%), based on the initial resected specimens. Immediately after detection of rapid regrowth and in adenomas that were resistant to bromocriptine or irradiation, the MIB1 index was always greater than 1.0%. Most patients with rapidly regrowing adenomas were well controlled by radiation therapy. Our results suggest that a MIB1 index greater than 1.0% may be a useful predictor of rapid regrowth of pituitary adenomas and may be useful for planning of therapy.

Adenoma↗
PubMed1997

Mutational analysis of the potato virus Y 5' untranslated region for alteration in translational enhancement in tobacco protoplasts.

The 185 nucleotide 5' untranslated region (5'UTR) of potato virus Y ordinary strain (PVY-O) showed translation-enhancing activity on the beta-glucuronidase (GUS) gene in tobacco protoplasts. Mutational analysis of the 5'UTR was done to find sequence motifs necessary for the enhancement. Deletions within the 1-130 nucleotide region of 5'UTR stimulated the GUS expression in some cases, while the GUS activity declined with deletions in the 131-185 nucleotide region. The results indicated that the last 55 nucleotides of PVY-O 5'UTR might play the much important role in the translational enhancement in plant cells.

Amino Acid Sequence↗
PubMed1997

Cloning, sequencing, and expression of a thermostable cellulase gene of Humicola grisea.

The egl2 gene coding a thermostable endoglucanase (EGL2) was cloned from Humicola grisea. The DNA sequence of egl2 predicted two putative introns in the coding region. The deduced amino acid sequence of EGL2 was 388 amino acids in length and showed 99.5% identity with the H. insolens CMC 3. In addition to TATA box and CAAT motifs, putative CREA binding sites were observed in the 5' upstream region of the egl2 gene. The egl2 gene was expressed in Aspergillus oryzae, and EGL2 was purified. EGL2 produced by A. oryzae showed a high activity toward carboxymethyl cellulose. The optimal temperature of EGL2 was 75 degrees C, and EGL2 had more than 80% residual activity after heating up to 75 degrees C for 10 min. This is the first report of enzymatic properties of the EGL2-type thermostable cellulase homologs from Humicola.

Amino Acid Sequence↗
PubMed1997

Oxygen sensitivity of NifA protein of Azospirillum lipoferum FS as suggested by gene cloning and expression in Escherichia coli.

We cloned and sequenced a 2.8-kb SalI fragment of Azospirillum lipoferum FS as a homologue of the Klebsiella oxytoca nifA gene. The amino acid sequence deduced from an open reading frame of 1872 bases showed 91% identity to that of the A. brasilense NifA, and the putative central sigma54 interaction domain was conserved as well as the C-terminal DNA-binding domain. The NifA function on the nifH promoter was examined in Escherichia coli using a combination of a nifA driver plasmid and a nifH-lacZ reporter plasmid, in which the transcriptional activation of the nifH promoter by the NifA was evaluated with the beta-galactosidase activity. The A. lipoferum NifA activated the nifH promoter solely under microaerobic conditions, while the K. oxytoca NifA activated it irrespective of the oxygen condition. These observations suggest that oxygen sensitivity is an intrinsic property of the A. lipoferum NifA.

Amino Acid Sequence↗
PubMed1997

[A surgery for an acute case of a ruptured aneurysm associated with idiopathic thrombocytopenic purpura: a case report].

A surgery for an case acute of a ruptured aneurysm with idiopathic thrombocytopenic purpura (ITP) is very rare. We encountered a case of a ruptured basilar artery (BA) superior cerebellar artery (SCA) aneurysm associated with ITP. A successful operation was carried out while the patient was in the acute stage. The patient was a 63-year-old female. She has been suffering from ITP for two years, when she experienced a sudden severe headache and vomitting on May 5, 1995. She was referred to our hospital as a case of subarachnoid hemorrhage estimated to be in group 2 according to the Fisher grade. Her neurological condition caused by the subarachnoid hemorrhage was grade 2 according to Hunt & Kosnik classification, and she was classified according to WFNS as grade 1. The number of platelets was, however, 2.3 x 10(4)/mm3 on admission. Cerebral angiography showed the aneurysm at the bifurcation of BA and SCA. The administration of platelet transfusion, betamethasone and gamma-globulin induced an increase of the number of platelets to 8.7 x 10(4) mm3 just before the operation. Neck clipping for the aneurysm was performed using platelet transfusion via the right pterional approach 25 hours after the onset. No tendency to bleed was recognized during the operation. The number of platelets was kept constantly at the level between 16.9 x 10(4)/mm3 and 22.0 x 10(4)/mm3 during the postoperative course with the administration of betamethasone. The postoperative course was good with no manifestations of delayed ischemic neurological deficits.

Acute Disease↗
PubMed1997

[A case of cortical reflex positive-negative myoclonus--electrophysiological study].

An 11-year-old girl who had the positive-negative myoclonus and the history of the generalized tonic clonic seizure was electrophysiologically studied. She had no siblings with either myoclonus or epilepsy, and her intellectual level was normal. She had no other neurological deficits including ataxia, pyramidal and extrapyramidal signs. Surface EMG showed a brief increase in the EMG activity followed by the silent period associated with positive and negative myoclonus during sustained wrist extension. Giant SEP and C reflex (38.6 ms) following electric stimulation of the median nerve at the wrist were obtained in the resting condition and the silent period (about 180 ms) following C reflex was obtained during voluntary contraction. Jerk-locked back averaging of the EEG time-locked to the onset of the myoclonic discharge recorded from the right biceps muscle showed a cortical spike at the left central region preceding the myoclonus onset by 12.6 ms. The latency of C reflex in this case was very short compared with that of previously reported cortical reflex myoclonus. The estimated cortical delay between the arrival of the somatosensory volley and the motor cortex discharge responsible for the C reflex was -1.0 ms and this value was shorter than that in patients with typical cortical reflex myoclonus (mean 3.7 +/- 1.1 ms). Conditioning stimuli (C) of the right median nerve at the wrist started to facilitate the amplitude of the motor evoked potential recorded from the right abductor pollicis brevis muscle after magnetic test stimuli (T) of the left motor cortex at 20 ms of the C-T interval. This C-T interval was shorter than that (24.6 +/- 1.6 ms) in patients with the typical cortical myoclonus. These electrophysiological findings suggested the shorter reflex pathway of the cortical reflex myoclonus in this case than in typical cortical reflex myoclonus. We speculated that the myoclonus was based upon the direct sensory projection from the thalamus to the motor cortex in this case.

Child↗
PubMed1997

[Electrophysiological study of a case of clinically diagnosed corticobasal degeneration with rhythmic myoclonus].

A 66-year-old man with clinically diagnosed corticobasal degeneration was studied electrophysiologically. The patient had bilateral forced grasping, rigidity, bradykinesia and hyperreflexia which were predominant on the right side, motor aphasia, constructional apraxia, forced laughing, dysequilibrium and myoclonus of the right upper extremity. Several anti-parkinsonism drugs were ineffective. Brain MRI revealed cortical atrophy of the fronto-temporo-parietal lobes with left predominance. On single photon emission computed tomography, cerebral blood perfusion was decreased, especially on the left side in the fronto-temporal lobes, basal ganglia and thalamus. Myoclonus was distal dominant, worse on action or posture, and was rhythmic, mimicking a tremor. On surface EMG recording of the myoclonus, agonist and antagonist muscle pairs were activated simultaneously and rhythmic activities with frequencies ranging from 7 to 8 Hz were seen. The patient had an enhanced C reflex with a relatively short latency (41.0 ms) after median nerve stimulation only at the right wrist. Additionally, during voluntary contraction, the time-constant EMG silence lasting for about 80-90 ms followed the C reflexes. On somatosensory evoked potentials (SEPs) to the median nerve stimulation, N20 latencies were normal and P25 and N33 amplitudes were not giant. There was no premovement corticat spike when a jerk-locked averaging method was used. Regarding motor evoked potentials (MEPs) elicited by magnetic brain stimulation, central motor conduction times were normal. The estimated cortical delay between the arrival of a somatosensory volley and the motor cortical discharge responsible for C reflex was 1.0 ms, which was shorter than those (3.1 +/- 0.9 ms) estimated in five patients with typical cortical reflex myoclonus. A conditioning stimulation (C) of the right median nerve produced marked facilitation of MEPs following magnetic stimulation of the left motor cortex, at conditioning-test intervals (C-T intervals) of 20-22 ms, whereas a conditioning stimulation of the left median nerve did not produce the same effect. These C-T intervals were thought to be very short, considering that N20 latency was 19.6 ms in this patient. The duration of the EMG silence following the C reflex corresponded to that of the EMG silence between muscle activities during his rhythmic myoclonus, and also the myoclonus was reset by occurrence of the C reflex. These electrophysiological findings indicate that his myoclonus was based upon the enhancement of direct sensory input from the thalamus to the motor cortex. Moreover, it is suggested that the existence of the time-constant EMG silence following the C reflex was related to the myoclonal rhythm.

Aged↗