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M Serizawa

Publications and source records attributed to M Serizawa.

At least 19 recordsLinked to original sources
PubMed2001

Regulation of the glv operon in Bacillus subtilis: YfiA (GlvR) is a positive regulator of the operon that is repressed through CcpA and cre.

Maltose metabolism and the regulation of the glv operon of Bacillus subtilis, comprising three genes, glvA (6-phospho-alpha-glucosidase), yfiA (now designated glvR), and glvC (EIICB transport protein), were investigated. Maltose dissimilation was dependent primarily upon the glv operon, and insertional inactivation of either glvA, glvR, or glvC markedly inhibited growth on the disaccharide. A second system (MalL) contributed to a minor extent to maltose metabolism. Northern blotting revealed two transcripts corresponding to a monocistronic mRNA of glvA and a polycistronic mRNA of glvA-glvR-glvC. Primer extension analysis showed that both transcripts started at the same base (G) located 26 bp upstream of the 5' end of glvA. When glvR was placed under control of the spac promoter, expression of the glv operon was dependent upon the presence of isopropyl-beta-D-thiogalactopyranoside (IPTG). In regulatory studies, the promoter sequence of the glv operon was fused to lacZ and inserted into the amyE locus, and the resultant strain (AMGLV) was then transformed with a citrate-controlled glvR plasmid, pHYCM2VR. When cultured in Difco sporulation medium containing citrate, this transformant [AMGLV(pHYCM2VR)] expressed LacZ activity, but synthesis of LacZ was repressed by glucose. In an isogenic strain, [AMGLVCR(pHYCM2VR)], except for a mutation in the sequence of a catabolite-responsive element (cre), LacZ activity was expressed in the presence of citrate and glucose. Insertion of a citrate-controlled glvR plasmid at the amyE locus of ccpA(+) and ccpA mutant organisms yielded strains AMCMVR and AMCMVRCC, respectively. In the presence of both glucose and citrate, AMCMVR failed to express the glv operon, whereas under the same conditions high-level expression of both mRNA transcripts was found in strain AMCMVRCC. Collectively, our findings suggest that GlvR (the product of the glvR gene) is a positive regulator of the glv operon and that glucose exerts its effect via catabolite repression requiring both CcpA and cre.

Bacillus subtilis↗
PubMed2001

[Effect of weekly docetaxel in patients with recurrent breast cancer].

A pilot trial was conducted to assess the tolerability and efficacy of a regimen with weekly docetaxel (TXT) in patients with metastatic breast cancer. The chemotherapy regimen consisted of a 30-minute weekly intravenous infusion of docetaxel (22-33 mg/m2/wk). Each 8-week cycle included 6 weekly treatments, followed by two weeks of rest. Thirteen patients were treated. All patients were evaluable for response: 0 CR (0%), 7 PR (53.8%), 3 NC (23.1%), 3 PD (23.1%). These results are almost the same as those with the administration of TXT (60 mg/m2) q3 wks. Toxicities observed were mild (< or = grade 2) and reversible, and included fatigue, nausea, neutropenia, and alopecia. This preliminary experience suggests a high level of clinical activity and excellent tolerability of the chemotherapy regimen at the given dose and schedule in patients with metastatic breast cancer.

Adult↗
PubMed1999

A novel mutation (Cys6Gly) in the Cu/Zn superoxide dismutase gene associated with rapidly progressive familial amyotrophic lateral sclerosis.

Autosomal-dominant familial amyotrophic lateral sclerosis (FALS) is associated with mutation in the gene that encodes Cu/Zn superoxide dismutase (SOD1). We identified a novel missense mutation of SOD-1 (Cys6Gly) in exon 1 in a Japanese woman and her family. The illness showed rapid progression similarly to the FALS with a mutation of Cys6Phe that was reported by Morita et al. (1996) (Morita, M., Aoki, M., Abe, K., Hasegawa, T., Sakuma, R., Onodera, Y., Ichikawa, N., Nishizawa, M. and Itoyama, Y., A novel two-base mutation in the Cu/Zn superoxide dismutase gene associated with familial amyotrophic lateral sclerosis in Japan. Neurosci. Lett., 205 (1996) 79-82). Mutation of the cystein at amino acid 6 might be associated with the rapid progression of ALS.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Clinicopathological study of an autopsy case with sensory-dominant polyradiculoneuropathy with antiganglioside antibodies.

A previously reported patient presenting sensory-dominant neuropathy with antiganglioside antibodies, bound preferentially to polysialogangliosides including GD1b, was autopsied. While axonal degeneration was predominant in the sural nerve, many demyelinated fibers were present in the spinal roots. Dorsal roots had undergone significant damage. These pathological findings were well correlated with the electrophysiological results showing decreased F-wave conduction velocities and conduction blocks in motor nerves and decreased or absent sensory action potentials in sensory nerves, with distribution of GD1b in nerve tissues such as dorsal root ganglia and paranodal myelin in the ventral and dorsal roots.

Aged↗
PubMed1999

Echogenicity of fetal lung and liver quantified by the grey-level histogram width.

Grey-level histogram width (GLHW) values of fetal lung and liver were studied in 52 healthy fetuses in 24 to 38 weeks of pregnancy, comparing them to the mean grey level (MGL), grey-level standard deviation (GLSD) and the coefficient of variation (GLCV). Fetal lung GLHW was larger in 30-38 weeks than at 24-29 weeks, but there was no change in liver GLHW. GLHW was smaller in fetal lung than in the liver in 24-29 weeks, with no difference in 30-38 weeks. The lung/liver GLHW ratios were less than 1 in 24-29 weeks, but they were 1 or more in 30-35 weeks. Both MGL of fetal lung and liver showed linear increases during pregnancy, but no difference was found between the two. Fetal lung GLSD tended to decrease during pregnancy. The GLCV values of fetal lung and liver decreased during pregnancy, and differed between 24-29 weeks and 30-38 weeks, whereas there was no difference between fetal lung and liver. The correlation coefficients of GLHW and MGL of fetal lung and liver to the weeks of pregnancy were moderate, and the coefficients of GLSD and GLCV to the weeks of pregnancy were small. In conclusion, quantitatively measured echogenicity of fetal lung increased in 30 or more weeks of pregnancy, and suggested antepartum changes of fetal lung tissue. The GLHW is reliable, because it was reproducible in various gain settings of various ultrasonic imaging devices. The MGL, GLSD and GLCV are less reliable, because the grey level varied by the gain changes among various machines.

Embryonic and Fetal Development↗
PubMed1998

Neural Network Computer Analysis of Fetal Heart Rate.

> Objective: A nonsubjective evaluation of intrapartum fetal heart rate (FHR) with a neural network (NNW) computer system and its clinical application. Methods: Eight simple FHR data were input into the NNW computer after 16-step normalizations. The computer was composed of 40 units in the input layer, 30 in intermediate layer, and 3 in the output layer, and the probabilities to be normal, suspicious, and pathological were obtained at the output. Before use, the computer was trained 10,000 times by 50-min teacher FHR data of 20 cases with known outcomes. The trained NNW computer was tested by FHRs of another 29 cases. The outcome probabilities in 15 min were calculated every 5 min in another 10 cases, and the bar graphs of the probabilities were displayed in sequence in the trendgrams. Results: The trained NNW computer was 100% accurate in the internal check; in the external check 86% of the results were evaluated correctly with the cardiotocogram, Apgar score, and umbilical arterial pH of the 29 test cases. The FHR scores of our conventional computer FHR analysis were higher in the suspicious and pathological groups than the normal group, and the fetal distress index was high in the pathological group. The trendgrams were simply accurate in typically normal or abnormal cases, transitory abnormal probabilities were shown in intermediate cases, and mixed suspicious and pathological probabilities suggested pathological outcome. Conclusions: The outcome probabilities and their trendgrams in the NNW FHR analysis are promising in objective decision making in the intrapartum stage.

Journal Article↗
PubMed1996

Increased plasma lipid peroxidation in patients with aceruloplasminemia.

Aceruloplasminemia is a newly recognized autosomal recessive disorder of iron metabolism due to mutations in the ceruloplasmin gene. Although the presence of these mutations reveals an essential role for ceruloplasmin in human biology, the mechanisms of tissue injury in this disease are unknown. We report here on the identification of increased plasma lipid peroxidation in multiple affected family members with aceruloplasminemia. Consistent with the absence of serum ceruloplasmin, plasma ferroxidase activity was markedly reduced and serum ferritin was significantly increased. Plasma lipid peroxidation was determined as thiobarbituric acid-reactive products (TBA products) in plasma samples from control, heterozygote, and affected patients. Basal levels of lipid peroxides were three times control values in patients with aceruloplasminemia and were significantly increased in these patients in the presence of copper ions and hydrogen peroxide. In each case these increases were suppressed by the addition of exogenous ceruloplasmin. These data suggest that increased susceptibility to lipid peroxidation may contribute to the unique neuropathology observed in patients with aceruloplasminemia and imply a role for free radical-mediated tissue injury in degenerative disorders of the basal ganglia.

Adult↗
PubMed1995

Aceruloplasminemia: molecular characterization of this disorder of iron metabolism.

Ceruloplasmin is an abundant alpha 2-serum glycoprotein that contains 95% of the copper found in the plasma of vertebrate species. We report here on the identification of a genetic defect in the ceruloplasmin gene in a patient previously noted to have a total absence of circulating serum ceruloplasmin in association with late-onset retinal and basal ganglia degeneration. In this patient T2 (transverse relaxation time)-weighted magnetic resonance imaging of the brain revealed basal ganglia densities consistent with iron deposition, and liver biopsy confirmed the presence of excess iron. Although Southern blot analysis of the patient's DNA was normal, PCR amplification of 18 of the 19 exons composing the human ceruloplasmin gene revealed a distinct size difference in exon 7. DNA sequence analysis of this exon revealed a 5-bp insertion at amino acid 410, resulting in a frame-shift mutation and a truncated open reading frame. The validity of this mutation was confirmed by analysis of DNA from the patient's daughter, which revealed heterozygosity for this same 5-bp insertion. The presence of this mutation in conjunction with the clinical and pathologic findings demonstrates an essential role for ceruloplasmin in human biology and identifies aceruloplasminemia as an autosomal recessive disorder of iron metabolism. These findings support previous studies that identified ceruloplasmin as a ferroxidase and are remarkably consistent with recent studies on the essential role of a homologous copper oxidase in iron metabolism in yeast. The clinical and laboratory findings suggest that additional patients with movement disorders and nonclassical Wilson disease should be examined for ceruloplasmin gene mutations.

Amino Acid Sequence↗
PubMed1994

Corticostriatal and corticotectal projections from visual cortical areas 17, 18 and 18a in the pigmented rat.

Regions of the visual cortex and the deep layers of the superior colliculus (SC) have been suggested to be functionally linked via an 'indirect' pathway through the basal ganglia. The present report demonstrates projections from the striate (area 17) and extrastriate (areas 18 and 18a) visual cortex in Long-Evans hooded rats to the striatum (ST) and SC with anterograde (biocytin) and retrograde (WGA-HRP and fluorescent dyes) tracers. Biocytin injections into each cortical area produced markedly different patterns of labeling in ST and SC. Injections into area 17 resulted in a dense labeling in the superficial layers of SC, with little labeling present in the deep layers of SC or ST. In contrast, injections into area 18a, which produced marked labeling in the deep layers of SC with moderate in the superficial layers, resulted in dense labeling in the caudal two-thirds of the dorsal region of ST; injections into area 18 produced numerous terminals mainly in the deep layers of SC and in the rostral two-thirds of the dorsal aspect of ST. WGA-HRP injections into ST resulted in numerous retrogradely labeled pyramidal neurons in areas 18 and 18a, but only a few labeled neurons were observed in area 17. Corticostriatal neurons in extrastriate visual cortex were distributed predominantly in layer V, with smaller numbers in layers II and III, whereas corticotectal neurons were located only in layer V of both the striate and extrastriate visual cortex. Although corticostriatal and corticotectal neurons were intermingled in layer V, no double-labeled neurons were observed following injections of different fluorescent dyes into ST and SC. It appears, therefore, that: 1) the major source of visual input to both ST and the deep layers of SC in the rat arises not from the primary visual cortex but from extrastriate visual areas; and that 2) the projections from the extrastriate visual area to ST and SC originate from different populations of corticofugal neurons.

Animals↗
PubMed1994

[Histological and radiobiological study on adult cases with ataxia telangiectasia].

Ataxia telangiectasia (AT) is a hereditary disease that involves both the immune and nervous system; its pathogenesis is believed to be due to disturbances in DNA repair system. Because children are usually affected, reports concerning adult patients are rare. In the present study, we performed comprehensive clinical, histological, and radiobiological examinations on two adult female siblings, currently 23 and 19 years old. The initial symptom was an ataxic gait, which began in the elder sister at the age of 20 and the younger sister at the age of 18. Both had mild telangiectasia in the bulbar conjunctiva and auricula. The neurological manifestations of both were gaze nystagmus, cerebellar ataxia, hyporeflexia, and vibratory sensation disturbance. Only the elder sister showed stocking type sensory disturbance. The MRI of both patients revealed cerebellar atrophy, especially in vermis. After either X-ray irradiation or bleomycin treatment, fibroblast survival curve showed a marked, dose-dependent declined in both patients compared with normal controls. Similar patterns were observed in both patients. After bleomycin treatment, no differences in the survival ratio of cultured fibroblasts could be found between these adult patients and those observed in younger children with classic AT. Biopsied sural nerves showed a decrease in the number of large myelinated fibers, with a few myelinated axons having relatively thin myelin. There were severe atrophic changes, with regenerative myelinated fibers in the elder sister. In conclusion, both adult patients with delayed onset AT displayed similar bleomycin hypersensitivity in fibroblasts as would be expected in children with AT. Radiobiological examinations and sural nerve biopsy suggest that both disturbed cellular regeneration and atrophic process may play a role in the neural involvement in this disease.

Adult↗