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Makoto Ueno

Publications and source records attributed to Makoto Ueno.

14 recordsLinked to original sources
PubMed2007

RNA-mediated gene silencing in the phytopathogenic fungus Bipolaris oryzae.

The Ascomycetous fungus Bipolaris oryzae is the causal agent of brown leaf spot disease in rice and is a model for studying photomorphogenetic responses by near-UV radiation. Targeted gene disruption (knockout) for functional analysis of photomorphogenesis-related genes in B. oryzae can be achieved by homologous recombination with low efficiency. Here, the applicability of RNA silencing (knockdown) as a tool for targeting endogenous genes in B. oryzae is reported. A polyketide synthase gene (PKS1), involved in fungal DHN melanin biosynthesis pathways, was targeted by gene silencing as a marker. The silencing vector encoding hairpin RNA of the PKS1 fragment was constructed in a two-step PCR-based cloning, and introduced into the B. oryzae genomic DNA. Silencing of the PKS1 gene resulted in albino phenotypes and reduction of PKS1 mRNA expression. These results demonstrate the applicability of targeted gene silencing as a useful reverse-genetics approach in B. oryzae.

Ascomycota↗
PubMed2007

Characterization of the BLR1 gene encoding a putative blue-light regulator in the phytopathogenic fungus Bipolaris oryzae.

Bipolaris oryzae is a filamentous ascomycetous fungus that causes brown leaf spot disease in rice. We isolated and characterized BLR1, a gene that encodes a putative blue-light regulator similar to Neurospora crassa white-collar 1 (WC-1). The deduced amino acid sequence of BLR1 showed high degrees of similarity to other fungal blue-light regulator protein. Disruption of the BLR1 gene demonstrated that this gene is essential for conidial development after conidiophore formation and for near-UV radiation-enhanced photolyase gene expression.

Amino Acid Sequence↗
PubMed2006

[Somatostatinoma].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed2005

Noninvasive assessment of tumor vascularity by contrast-enhanced ultrasonography and the prognosis of patients with nonresectable pancreatic carcinoma.

BACKGROUND: Studies have shown that angiogenesis is one of the factors that influences the prognosis of patients with solid tumors, including pancreatic carcinomas. However, none have assessed noninvasively the relation between angiogenesis and prognosis in patients with pancreatic carcinoma. Contrast-enhanced ultrasonography (US) not only is a convenient, harmless, and noninvasive imaging modality, but it also provides detailed information on tumor vascularity. The objectives of this study were to assess the vascularity of pancreatic carcinoma noninvasively by contrast-enhanced US and to clarify the prognostic value of tumor vascularity in patients with nonresectable pancreatic carcinoma. METHODS: Thirty-five consecutive patients with pathologically confirmed, nonresectable pancreatic carcinoma were examined with contrast-enhanced US before systemic chemotherapy. The correlations among tumor vascularity, clinicopathologic factors, and clinical outcomes then were analyzed statistically to investigate prognostic indicators. RESULTS: The median time to progression (TTP) was longer in patients who had avascular tumors compared with patients who had vascular tumors (110 days vs. 28 days, respectively; P=0.0072; log-rank test). The median survival also was longer in patients who had avascular tumors (267 days vs. 115 days, respectively; P=0.0034; log-rank test). A multivariate analysis using a Cox proportional hazards model revealed that tumor vascularity was a significant, independent factor that influenced TTP (P <0.001) and survival (P=0.022) along with primary tumor size and serum lactate dehydrogenase (LDH) level, which are well known as prognostic factors in patients with pancreatic carcinoma. CONCLUSIONS: The current results indicated that contrast-enhanced US may be useful in assessing the prognosis of patients with nonresectable pancreatic carcinoma who receive systemic chemotherapy.

Adult↗
PubMed2005

[Evaluation of biliary stenting therapy for malignant biliary stricture at our hospital].

The clinical results of biliary stenting therapy for non-resectable malignant biliary stricture were assessed for patency periods and survival periods in consideration of the types of stents and disease. The subjects were 51 patients with non-resectable malignant biliary stricture due to disease of the pancreas and biliary tract treated at our hospital between April 2001 and March 2005. No significant differences were observed in the patency periods and survival periods among the various types of stents. In regard to the type of disease, the survival period for biliary tract cancer was longer (616 +/- 246 days) than those for other diseases. There was no difference in the number of times of stenting among the various stents, and jaundice was effectively reduced. No patients in our series died of failure to reduce jaundice. We therefore considered it necessary to choose a proper stent indwelling route and a stent type according to stricture site, disease type and PS (performance status) at the time of stenting. The usefulness of the biliary stenting therapy for non-resectable malignant biliary stricture was suggested.

Adult↗
PubMed2004

Cloning, functional analysis and expression of a scytalone dehydratase gene ( SCD1) involved in melanin biosynthesis of the phytopathogenic fungus Bipolaris oryzae.

Scytalone dehydratase is involved in the production of fungal dihydroxynaphthalene melanin. We isolated and characterized SCD1, a gene encoding scytalone dehydratase, from the phytopathogenic fungus Bipolaris oryzae. Sequence analysis showed that SCD1 encodes a putative protein that has 185 amino acids, a molecular weight of 21 kDa and 51-75% sequence identity to other fungal scytalone dehydratases. Targeted disruption of SCD1 showed that this gene is necessary for melanin biosynthesis in B. oryzae. Northern blot analysis showed that SCD1 transcripts are specifically enhanced by near-ultraviolet (300-400 nm) radiation.

Amino Acid Sequence↗
PubMed2003

Novel oxidative alpha-tosyloxylation of alcohols with iodosylbenzene and p-toluenesulfonic acid and its synthetic use for direct preparation of heteroaromatics.

alpha-Tosyloxyketones and alpha-tosyloxyaldehydes were directly prepared from alcohols by treatment with iodosylbenzene and p-toluenesulfonic acid monohydrate in good yields. This method can be used for the direct preparation of thiazoles, imidazoles, and imidazo[1,2-a]pyridines from alcohols in good to moderate yields by the successive treatment with iodosylbenzene and p-toluenesulfonic acid monohydrate, followed by thioamides, benzamidine, and 2-aminopyridine, respectively.

Journal Article↗
PubMed2003

Cortical correlates of vestibulo-ocular reflex modulation: a PET study.

To elucidate cortical correlates of vestibulo-ocular reflex (VOR) modulation, we observed cortical activation during fixation suppression and habituation of caloric vestibular nystagmus in 12 normal subjects, using PET. Significant positive correlation between regional cerebral blood flow (rCBF) and slow phase eye velocity of caloric nystagmus was observed in the middle and posterior insula, inferior parietal lobule, temporal pole, right fusiform gyrus, lingual gyrus, and cerebellar vermis and hemisphere. The rCBF increase in the insular region and the inferior parietal lobule was lateralized depending on the direction of the nystagmus. Caloric nystagmus was suppressed as a result of visual fixation, during which time the area around the right frontal eye field, temporal pole, inferior temporal gyrus, a broad area in the visual cortex, including fusiform and lingual gyrus, cerebellar uvula/nodulus and flocculus, exhibited positive correlation with fixation suppression of caloric nystagmus, while vestibular cortices exhibited negative correlation. The caloric nystagmus habituated with repetition of stimulation. With habituation, we observed activation in the right anterior cingulate gyrus, left superior parietal lobule and right cuneus, and deactivation in the anterior insula, cingulate gyrus, inferior parietal lobule and occipito-temporal visual cortex. The region that showed significant co-activation with fixation suppression and habituation of caloric nystagmus was the right cuneus, and significant co-deactivation was observed in the anterior insula, cingulate gyrus, inferior parietal lobule and middle temporal visual cortex. The present results support previous observations that the parieto-insular cortex and inferior parietal lobule are involved in processing of vestibular information, and, in addition, suggest that activation may depend on the direction of nystagmus. Deactivation of vestibular cortices during visual fixation supports the concept of inhibitory visual-vestibular interaction in the cortex. Significant activation of the cingulate, superior parietal and visual cortices, and cerebellar vermis accompanying reduction of caloric response with repeated stimuli suggests possible involvement of these regions in vestibular habituation. Common activation of the cuneus in visual cortex and deactivation of vestibular and visuo-spatial association cortices by both visual suppression and habituation of VOR suggests that these two mechanisms are not completely independent but may share some cortical and subcortical regions.

Adult↗
PubMed2003

Inner ear hearing loss modulates ipsilateral temporal lobe activation by monaural speech stimuli.

We examined cortical activation by speech in patients with moderate inner ear hearing loss using PET to investigate the response of the language network to insufficient speech input. We made two word lists, well-perceived words and poorly-perceived words, and measured rCBF during monaural presentation of these words. Well-perceived words activated bilateral temporal lobes, bilateral inferior frontal gyri (IFG) and left angular gyrus (AG) regardless of the ear stimulated, Poorly-perceived words activated contralateral temporal lobe and bilateral IFG, while little or no activation was observed in the ipsilateral temporal lobe and left AG. Insufficient activation of the temporal lobe ipsilateral to the ear stimulated might correlated with less accurate word comprehension in patients with inner ear hearing loss.

Acoustic Stimulation↗
PubMed2003

Increased tryptophan decarboxylase and monoamine oxidase activities induce Sekiguchi lesion formation in rice infected with Magnaporthe grisea.

Sekiguchi lesion (sl)-mutant rice infected with Magnaporthe grisea showed increased light-dependent tryptophan decarboxylase (TDC) and monoamine oxidase (MAO) activities. TDC and MAO activities were observed before the penetration of M. grisea to rice cells and maintained high levels even after Sekiguchi lesion formation. Light-dependent expression of TDC gene was observed in leaves inoculated with M. grisea before Sekiguchi lesion formation. Spore germination fluid (SGF) of M. grisea also induced Sekiguchi lesion formation accompanied by increased enzymes activities and tryptamine accumulation. Sekiguchi lesion was also induced by treatments with tryptamine and beta-phenylethylamine, which are substrates for MAO, but was not induced by non-substrates such as indole-3-propionic acid, (+/-)-phenylethylamine and tryptophan under light. Light-dependent induction of Sekiguchi lesion by tryptamine was significantly inhibited in the presence of MAO inhibitors, metalaxyl and semicarbazide, and H2O2-scavengers, ascorbic acid and catalase. H2O2 in M. grisea-infected leaves with and without Sekiguchi lesions was demonstrated directly in situ by strong 3,3'-diaminobenzidine (DAB) staining. On the other hand, H2O2 induced Sekiguchi lesions on leaves of cv. Sekiguchi-asahi under light, but not in darkness. This difference was associated with the decrease of catalase activity in infected leaves under light and the absence of decrease in darkness. We hypothesize that the H2O2-induced breakdown of cellular organelles such as chloroplasts and mitochondria in mesophyll cells may cause high TDC and MAO activities and the development of Sekiguchi lesion, and that the sl gene products in wild-type rice may function as a suppressor of organelle breakdown caused by chemical or environmental stress.

Aromatic-L-Amino-Acid Decarboxylases↗
PubMed2002

A simplified double-injection method to quantify cerebral blood flow and vascular reserve using iodine-123 IMP-SPECT.

UNLABELLED: We developed and evaluated a simplified double-injection method for iodine-123 N-isopropyl-p-iodoamphetamine (IMP) to quantify regional cerebral blood flow (rCBF) twice in a single SPECT session. The method enabled rapid calculations of rCBF with five 10-minute SPECT scans, a fixed distribution volume (Vd), and one-point arterial blood sampling to calibrate a standard input function (SIF). METHODS: Sixty neurological patients were examined to measure rCBF twice in a single session of IMP-SPECT. Patients underwent frequent arterial blood sampling with two injections of IMP and acetazolamide challenge. We generated the SIF and determined the optimal Vd and calibration time (t(cal)) for the SIF in 30 patients. Validities of the fixed t(cal) and Vd were assessed in the remaining 30 patients. Simulation studies were also performed to evaluate the error sensitivity of the method. RESULTS: The optimal t(cal) and Vd were 34 min and 30 ml/ml, respectively. The method was robust in rCBF calculation with noisy SPECT data and yielded rCBF with negligible bias and acceptable errors compared with those obtained by the double-injection method previously reported. CONCLUSION: The method can be applied to measure rCBF twice in a single SPECT session more easily and less invasively.

Aged↗
PubMed2002

Unilateral occlusion of the middle cerebral artery after varicella-zoster virus infection.

We report a 4-year-old child who developed hemiplegia 6 months after varicella-zoster virus (VZV) infection. Cerebral angiography showed complete occlusion of the right middle cerebral artery with basal moyamoya vessels. Elevation of anti-VZV antibody in the cerebrospinal fluid indicated central nervous system involvement. The association between VZV cerebral angitis and unilateral occlusion of right middle cerebral artery is discussed.

Child, Preschool↗
PubMedDate not supplied

A case of sectorial benign flecked retina.

PURPOSE: A case of sectorial benign flecked retina not associated with an RDH5 gene mutation is reported. METHODS: A 51-year-old woman showed multiple yellow-white flecks in both eyes similar to those of benign flecked retina but in only the upper half of the retina. We carried out clinical, electrophysiological, and molecular genetic examinations of the patient. RESULTS: Visual acuity was 20/20 OD and 20/20 OS. Fluorescein angiography showed diffuse irregular hypofluorescence that did not correspond to the flecked lesions. A Goldmann-Weeker adaptometer test revealed that the visual threshold of the upper retina was approximately 0.6 to 0.8 log units higher than that of the lower retina. No mutations of the RDH5 gene were detected in exons 2-5 or in the flanking intron sequences. CONCLUSIONS: To our knowledge, this is the first report of sectorial benign flecked retina, and the flecks may not be caused by an RDH5 gene mutation.

Alcohol Oxidoreductases↗