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Susumu Ito

Publications and source records attributed to Susumu Ito.

At least 19 recordsLinked to original sources
PubMed2007

Ancestral sequence evolutionary trace and crystal structure analyses of alkaline alpha-amylase from Bacillus sp. KSM-1378 to clarify the alkaline adaptation process of proteins.

The crystal structure of alkaline liquefying alpha-amylase (AmyK) from the alkaliphilic Bacillus sp. KSM-1378 was determined at 2.1 A resolution. The AmyK structure belongs to the GH13 glycoside hydrolase family, which consists of three domains, and bound three calcium and one sodium ions. The alkaline adaptation mechanism of AmyK was investigated by the ancestral sequence evolutionary trace method and by extensive comparisons between alkaline and nonalkaline enzyme structures, including three other protein families: protease, cellulase, and phosphoserine aminotransferase. The consensus change for the alkaline adaptation process was a decrease in the Lys content. The loss of a Lys residue is associated with ion pair remodeling, which mainly consists of the loss of Lys-Asp/Glu ion pairs and the acquisition of Arg ion pairs, preferably Arg-Glu. The predicted replacements of the positively charged amino acids were often, although not always, used for ion pair remodeling.

Amino Acids↗
PubMed2007

Extremely high alkaline protease from a deep-subsurface bacterium, Alkaliphilus transvaalensis.

A new high-alkaline protease (ALTP) was purified to homogeneity from a culture of the strictly anaerobic and extremely alkaliphilic Alkaliphilus transvaalensis. The molecular mass was 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme showed the maximal caseinolytic activity higher than pH 12.6 in KCl-NaOH buffer at 40 degrees C. Hydrolysis of the oxidized insulin B-chain followed by mass spectrometric analysis of the cleaved products revealed that as many as 24 of the total 29 peptide bonds are hydrolyzed in a block-cutting manner, suggesting that ALTP has a widespread proteolytic functions. Calcium ion had no effect on the activity and stability of ALTP, unlike known subtilisins. The deduced amino acid sequence of the enzyme comprised 279 amino acids plus 97 prepropeptide amino acids. The amino acid sequence of mature ALTP was confirmed by capillary liquid chromatography coupled to tandem mass spectrometry, which was the 93% coverage of the deduced amino acid sequence. The mature enzyme showed moderate homology to subtilisin LD1 from the alkaliphilic Bacillus sp. strain KSM-LD1 with 64% identity, and both enzymes formed a new subcluster at an intermediate position among true subtilisins and high-alkaline proteases in a phylogenetic tree of subtilase family A. ALTP is the first high-alkaline protease reported from a strict anaerobe in this family.

Amino Acid Sequence↗
PubMed2006

Population dynamics of Bifidobacterium species in human feces during raffinose administration monitored by fluorescence in situ hybridization-flow cytometry.

The population dynamics of bifidobacteria in human feces during raffinose administration were investigated at the species level by using fluorescence in situ hybridization (FISH) coupled with flow cytometry (FCM) analysis. Although double-staining FISH-FCM using both fluorescein isothiocyanate (FITC) and indodicarbocyanine (Cy5) as labeling dyes for fecal samples has been reported, the analysis was interfered with by strong autofluorescence at the FITC fluorescence region because of the presence of autofluorescence particles/debris in the fecal samples. We circumvented this problem by using only Cy5 fluorescent dye in the FISH-FCM analysis. Thirteen subjects received 2 g of raffinose twice a day for 4 weeks. Fecal samples were collected, and the bifidobacterial populations were monitored using the established FISH-FCM method. The results showed an increase in bifidobacteria from about 12.5% of total bacteria in the prefeeding period to about 28.7 and 37.2% after the 2-week and 4-week feeding periods, respectively. Bifidobacterium adolescentis, the Bifidobacterium catenulatum group, and Bifidobacterium longum were the major species, in that order, at the prefeeding period, and these bacteria were found to increase nearly in parallel during the raffinose administration. During the feeding periods, indigenous bifidobacterial populations became more diverse, such that minor species in human adults, such as Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium dentium, and Bifidobacterium angulatum, proliferated. Four weeks after raffinose administration was stopped, the proportion of each major bifidobacterial species, as well as that of total bifidobacteria, returned to approximately the original values for the prefeeding period, whereas that of each minor species appeared to differ considerably from its original value. To the best of our knowledge, these results provide the first clear demonstration of the population dynamics of indigenous bifidobacteria at the species level in response to raffinose administration.

Adult↗
PubMed2006

A patient with early syphilis complicated by fatty liver who showed an alleviation of hepatopathy accompanied by jaundice after receiving anti-syphilitic therapy.

A 42-year-old male with visceral obesity and a fatty liver presented with hepatopathy accompanied by jaundice and was diagnosed to have early syphilis based on the results of standard serologic tests and clinical findings. Both the subjective and objective findings including hepatopathy were rapidly alleviated by anti-syphilitic therapy. Severe hepatopathy accompanied by jaundice used to be considered a rare complication. However, due to contemporary unhealthy lifestyle patterns characterized by hypernutrition and a lack of exercise the occurrence of fatty liver is now dramatically increasing. Our findings suggest that the occurrence of fatty liver can exacerbate the damage to the hepatic parenchyma due to a Treponema pallidum infection.

Adult↗
PubMed2006

Effects of estradiol and progesterone on tumor necrosis factor alpha-induced apoptosis in human hepatoma HuH-7 cells.

Oxidative stress, including the generation of reactive oxygen species (ROS), is known to be involved in apoptosis. Preventing apoptosis may thereby induce a malignant transformation of liver tumor cells. Estradiol (E2) is a potent endogenous antioxidant. We examined the proapoptotic role of progesterone as well as the antiapoptotic role of E2 in human hepatoma HuH-7 cells in a state of early apoptosis induced by tumor necrosis factor (TNF) alpha. The TNF alpha-induced ROS generation, lipid peroxidation, antioxidant enzyme consumption, a proapoptotic predominant expression of Bcl-2 family proteins, and a disruption of mitochondrial membrane potential were all inhibited by E2, and then they were further stimulated by progesterone in HuH-7 cells. The inhibitory effects of E2 were blocked by coincubation with progesterone. Treatment with the progesterone receptor antagonist RU486 led to the blockage of the progesterone-mediated responses to E2 pretreatment in TNF alpha-induced apoptosis. These findings demonstrate that E2 inhibits the TNF alpha-induced early apoptosis in hepatoma cells, by suppressing the oxidative stress processes, whereas progesterone acts in a manner opposite from the effects of E2, and the inhibitory effects of E2 were blocked by progesterone, thus leading to the apoptosis of hepatoma cells.

Antibodies, Monoclonal↗
PubMed2006

Intestinal Behcet's disease with esophageal ulcers and colonic longitudinal ulcers.

Intestinal Behcet's disease in a 38-year-old woman was diagnosed because of the history of recurrent oral aphthous ulcers, erythema nodosum-like eruptions, genital ulcer, and endoscopic findings of esophageal and ileocolonic punched-out ulcers with colonic longitudinal ulcers. Esophageal lesions and colonic longitudinal ulcers are rarely seen in intestinal Behcet's disease. The ulcers of esophagus and ileocolon healed with 3 wk of treatment with prednisolone and mesalazine without any adverse effect. Mesalazine may decrease the total dose of prednisolone required to treat the disease.

Adult↗
PubMed2006

Salt-activated endoglucanase of a strain of alkaliphilic Bacillus agaradhaerens.

An endoglucanase was purified to homogeneity from an alkaline culture broth of a strain isolated from seawater and identified here as Bacillus agaradhaerens JAM-KU023. The molecular mass was around 38-kDa and the N-terminal 19 amino acids of the purified enzyme exhibited 100% sequence identity to Cel5A of B. agaradhaerens DSM8721(T). The enzyme activity increased around 4-fold by the addition of 0.2-2.0 M NaCl in 0.1 M glycine-NaOH buffer (pH 9.0). KCl, Na2SO4, NaBr, NaNO3, CH3COONa, LiCl, NH4NO3, and NH4Cl also activated the enzyme up to 2- to 4-fold. The optimal pH and temperature values were pH 7-9.4 and 60 degrees C with 0.2 M NaCl, but pH 6.5-7 and 50 degrees C without NaCl; enzyme activity increased approximately 6-fold at 60 degrees C with 0.2 M NaCl compared to that at 50 degrees C without NaCl in 0.1 M glycine-NaOH buffer (pH 9.0). The thermostability and pH stability of the enzyme were not affected by NaCl. The enzyme was very stable to several chemical compounds, surfactants and metal ions (except for Fe2+ and Hg2+ ions), regardless whether NaCl was present or not.

Amino Acid Sequence↗
PubMed2006

Oral delivery of diclofenac sodium using a novel solid-in-oil suspension.

The present work reports on a new pharmaceutical formulation for oral delivery of diclofenac sodium (DFNa), a non-steroidal anti-inflammatory drug (NSAID). Although DFNa itself is water-soluble at neutral pH, it was readily suspended in soybean oil via complex formation with an edible lipophilic surfactant and a matrix protein. The resulting solid-in-oil (S/O) suspension containing stably encapsulated DFNa in an oil phase markedly reduced the risks for gastrointestinal ulcers upon oral administration even at the LD(50) level in rats (ca. 50 mg/kg DFNa). In addition, plasma concentration of DFNa upon administration of an S/O suspension was comparable with that of the aqueous counterpart at the same DFNa dose. These results indicate the potential use of S/O suspensions as novel oil-based pharmaceutical formulations for oral delivery of water-soluble drugs without causing severe mucitis.

Administration, Oral↗
PubMed2006

Colonic pseudolipomatosis, microscopically classified into two groups.

BACKGROUND: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. METHODS: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. RESULTS: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal-looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal-looking surface or non-elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable-sized vacuoles, and were related to lymph follicles. CONCLUSION: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.

Adult↗
PubMed2006

Duodenal lymphangitis carcinomatosa: endoscopic characteristics and clinical significance.

BACKGROUND AND AIM: Duodenal lymphangitis carcinomatosa has been sporadically described, but so far little attention has been paid to duodenal lymphangitis carcinomatosa. METHODS: Four cases with duodenal lymphangitis carcinomatosa were endoscopically and histologically examined. RESULTS: The four cases exhibited multiple polypoid lesions along the Kerckring's folds and/or were covered by characteristically granular, non-ulcerated mucosa upon thickening. The granularity seems to been caused by dilated lymph vessels containing the carcinoma cells. The lesions were microscopically characterized by: (i) involvement of lymph vessels located in the upper portion of the lamina propria; (ii) no inflammatory changes; and (iii) no desmoplastic changes. Primary sites were thought to be the stomach in case 1, the pancreas in cases 2 and 4, and unknown in case 3. All patients died within 6 months after admission or endoscopic examination. CONCLUSIONS: As duodenal lymphangitis carcinomatosis shows characteristic endoscopic appearance, endoscopic diagnosis is not difficult. We should realize that the lesion represents extremely poor prognosis, and it should be distinguished from ordinary metastatic duodenal carcinoma.

Aged↗
PubMed2006

High-resolution quantitative imaging of mammalian and bacterial cells using stable isotope mass spectrometry.

BACKGROUND: Secondary-ion mass spectrometry (SIMS) is an important tool for investigating isotopic composition in the chemical and materials sciences, but its use in biology has been limited by technical considerations. Multi-isotope imaging mass spectrometry (MIMS), which combines a new generation of SIMS instrument with sophisticated ion optics, labeling with stable isotopes, and quantitative image-analysis software, was developed to study biological materials. RESULTS: The new instrument allows the production of mass images of high lateral resolution (down to 33 nm), as well as the counting or imaging of several isotopes simultaneously. As MIMS can distinguish between ions of very similar mass, such as 12C15N- and 13C14N-, it enables the precise and reproducible measurement of isotope ratios, and thus of the levels of enrichment in specific isotopic labels, within volumes of less than a cubic micrometer. The sensitivity of MIMS is at least 1,000 times that of 14C autoradiography. The depth resolution can be smaller than 1 nm because only a few atomic layers are needed to create an atomic mass image. We illustrate the use of MIMS to image unlabeled mammalian cultured cells and tissue sections; to analyze fatty-acid transport in adipocyte lipid droplets using 13C-oleic acid; to examine nitrogen fixation in bacteria using 15N gaseous nitrogen; to measure levels of protein renewal in the cochlea and in post-ischemic kidney cells using 15N-leucine; to study DNA and RNA co-distribution and uridine incorporation in the nucleolus using 15N-uridine and 81Br of bromodeoxyuridine or 14C-thymidine; to reveal domains in cultured endothelial cells using the native isotopes 12C, 16O, 14N and 31P; and to track a few 15N-labeled donor spleen cells in the lymph nodes of the host mouse. CONCLUSION: MIMS makes it possible for the first time to both image and quantify molecules labeled with stable or radioactive isotopes within subcellular compartments.

Adipocytes↗
PubMed2006

Principle and clinical usefulness of the infrared fluorescence endoscopy.

Since there is no infrared fluorescence materials in the living body, infrared fluorescence labeling materials are very useful for making a diagnosis of a micro cancer. We have developed an infrared fluorescence endoscope (IRFE) and indocyanin green (ICG)-derivative as infrared fluorescence labeling materials to evaluate gastrointestinal neoplastic lesions. The study aims were to apply an IRFE and to demonstrate its usefulness in detecting cancerous tissue using an antibody coupled with ICG-derivative. IRFE consisted of an infrared endoscope equipped with excitation (710-790 nm) and barrier (810-920 nm) filters and an intensified CCD camera. We have developed ICG N-hydroxy sulfo succinimide ester (ICG-sulfo-OSu) and 3-ICG-acyl-1, 3-thiazolidine-2-thione (ICG-ATT) as an infrared fluorescent-labeling reagent. ICG-derivative-labeled mouse anti-human carcinoembryonic antigen (CEA) antibody and MUC1 antibody were employed in this study. Moreover, we examined the ability of a reinforcement agent, octylglucoside, to intensity fluorescence from the labeled antibody. Biopsy specimens of gastric cancer were stained with anti-CEA antibody by the avidin-biotinylated peroxidase complex method. Among the positive specimens, freshly resected stomach from three cases were used for the infrared (IR) imaging analysis. The incubation of freshly resected stomach specimens with ICG-anti-CEA antibody-complex resulted in positive staining of the tumor sites by IRFE, and the IR fluorescent images correlated well with the tumor sites. The immunohistochemical studies suggested that the intensity of IR fluorescence of ICG-ATT-MUC1 was stronger than that of ICG-sulfo-OSu. In tumor sections, the reinforcement agent intensified fluorescence, ever at low antibody concentrations. Therefore, we conclude that an anti-CEA (and/or MUC1) antibody with affinity for cancerous lesions and labeled with ICG-derivative can be imaged with this IRFE. Specific antibodies tagged with ICG-derivative with the reinforcement agent can label cancer cells and generate a strong enough fluorescent signal to detect small cancers when examined with an IR fluorescence endoscope.

Animals↗
PubMed2006

Expression analysis of a mouse orthologue of HSFY, a candidate for the azoospermic factor on the human Y chromosome.

Heat shock transcription factor on Y (HSFY) is located in one of three candidate regions for azoospermic factor (AZF), AZFb on the Y chromosome. We and others have already revealed that some azoospermic males are missing the regions of the Y chromosome including HSFY. Previously, we showed that murine HSFY-like sequence [mHSFYL (Riken cDNA 4933413G11Rik)], which is the mouse orthologue of HSFY, is exclusively expressed in testis. The sequences encoding the presumed DNA-binding domain in HSFY and mHSFYL were found in other mammals such as dogs, cows and chickens. To elucidate mHSFYL expression in the testes in detail, we carried out in situ hybridization. mHSFYL was predominantly expressed in round spermatids. Furthermore, we clarified the intracellular distribution of mHSFYL in COS1 cells with HA- or GFP-tagged proteins. Both HA-mHSFYL and GFP-mHSFYL were located in the nucleus. Our results suggest that HSFY/mHSFYL may have evolutionarily conserved functions for spermatogenesis.

Amino Acid Sequence↗
PubMed2006

Relationship between adhesion molecules with hs-CRP and changes therein after ARB (Valsartan) administration in patients with obstructive sleep apnea syndrome.

It has been reported that a relationship exists between obstructive sleep apnea syndrome (OSAS) and cardiovascular and cerebrovascular diseases. To address this issue, we evaluated whether OSAS is associated with adhesion molecules and inflammatory signs, important indicators of atherosclerosis. Levels of high-sensitivity CRP (hs-CRP) and intercellular adhesion molecule-1 (ICAM-1) were measured in 30 patients with ischemic heart disease, confirmed by coronary arteriography (IHD group). Twenty healthy volunteers without sleep apnea were used as controls (Group N). Sleeping respiratory information was collected using a portable sleep polygraph, together on information about oronasal flow, tracheal sound, chest respiration, and percutaneous oxygen saturation (SpO2) to obtain the apnea-hypopnea index (AHI). In the IHD group, 9 (30%) of the 30 patients showed evidence of OSAS [IHD(AHI> or = 40) group] and 21 did not [IHD(AHI<40) group]. The levels of hs-CRP and ICAM-1 were significantly higher in the IHD group than in the N group (p<0.01). Moreover, the levels of hs-CRP and ICAM-1 were significantly higher in the IHD(AHI > or = 40) group than in the IHD(AHI<40) group (p<0.01). However, after the administration of valsartan, angiotensin II receptor antagonists (ARB) to both IHD groups, the levels of hs-CRP and ICAM-1 decreased significantly in both groups. Moreover, a multivariate analysis revealed that the levels of hs-CRP and ICAM-1 were associated with the severity of sleep apnea. These findings suggest that, in OSAS the levels of hs-CRP and ICAM-1 are decreased and that the administration of ARB decreases the risk of atherosclerosis.

Aged↗
PubMed2006

Relationships between thermic effect of food, insulin resistance and autonomic nervous activity.

BACKGROUND: The thermic effect of food (TEF) is higher in lean than in obese human subjects. OBJECTIVE: Relationships between TEF and insulin resistance during meals, from the point of view of autonomic nervous activity, were evaluated. METHODS: Autonomic nervous activity was evaluated in 20 young adults using the spectral analysis of heart rate variability from one hour before to two hours after a meal. Heart rate data were analyzed based on low frequency components (LF power, 0.04-0.15 Hz), high frequency components (HF power, 0.15-0.40 Hz), and LF/HF ratios. Energy expenditure and the TEF were measured 30 min after a meal. Homeostasis model of insulin resistance index (HOMA-IR) was also measured. RESULTS: The LF/HF ratio was significantly increased 30 min after a meal (p<0.05). No correlation between LF power and HF power with TEF was found, but the LF/HF ratio was significantly and positively correlated with TEF (r=+0.56, p<0.05). Moreover, a significant negative correlation was found between the HOMA-IR and TEF (r=-0.601, p<0.05). CONCLUSIONS: The findings suggest that a reduction in insulin sensitivity induces a poor response of sympathetic nervous activity in the postprandial phase and a reduction in postprandial energy expenditure.

Adult↗
PubMed2006

Evaluation of episodes of sleep apnea in patients with liver cirrhosis.

OBJECTIVE: Obstructive sleep apnea syndrome (OSAS) has been reported to be a new complication of liver cirrhosis with ascites. This fact prompted a study of episodes of sleep apnea as a function of the severity of cirrhosis. METHODS: Forty eight patients with type C liver cirrhosis were divided according to the Child-Pugh score into 3 groups: Group A (16 patients with grade A cirrhosis), Group B (16 patients with grade B cirrhosis), and Group C (16 patients with grade C cirrhosis). Portable sleep polygraphs (Fuji RC, Inc. Tokyo, Japan) were attached to the subjects, and oronasal respiration, tracheal sounds, respiratory movements of the chest, and percutaneous arterial oxygen saturation continuously were recorded. A decrease in the mean airflow to 50% or less was defined as hypopnea, and the number per hour of episodes of apnea and hypopnea per hour lasting 10 seconds or longer (AHI) was counted. A Holter ECG was also recorded, and spectral heart rate variability during sleep was analyzed by measuring low frequency power (0.04-0.15 Hz, LF power), high frequency power (0.15-0.40 Hz, HF power), the ratio of LF power to HF power (LF/HF ratio), and very low frequency power (0.008-0.04 Hz, VLF power). The difference in QT interval between the lead CM5 and the lead CM1 (QTc dispersion) was also examined. RESULTS: AHI was significantly higher in Group C than in Groups A and B (p<0.05). In Group C, 6 patients with 20 times or more AHI per hour, obstructive sleep apnea, in which respiratory chest movements occur but oronasal respiration decreases or disappears, was observed. Spectral analyses of heart rate variability showed a decrease in HF power without sleep apnea, but increases in HF power and VLF power were observed during sleep apnea. The QTc dispersion increased during episodes of sleep apnea. CONCLUSIONS: As the stage of liver cirrhosis advanced, sleep apnea appeared, and changes in autonomic nervous activities were observed. Furthermore, QTc dispersion was increased during episodes of sleep apnea, presumably increasing the risk of ventricular arrhythmia.

Aged↗
PubMed2006

Effects of thrombus suction therapy on myocardial blood flow disorders in males with acute inferior myocardial infarction.

Several studies have reported that the use of a distal protection device decreases the incidence of slow-flow and/or no-reflow in patients with myocardial infarctions. In the present study, we investigated the influence of a RESCUE/Thrombuster system and a PercuSurge GuardWire catheter on coronary microcirculation disorders in patients with acute myocardial infarction using the natriuretic polypeptide (ANP), the brain natriuretic peptide (BNP), and (99m)Tc-tetrofosmin myocardial scintigraphy (TF). The group consisted of a 77 patients with initial inferior myocardial infarction who had undergone emergency coronary angioplasty. The patients were randomly divided into: Group D (n=28), in which a direct stent alone was inserted, Group R/T (n=25), in which a stent was inserted after RESCUE system or a Thrombuster system was performed, and Group P (n=24), in which a stent was inserted after thrombus suction using a PercuSurge GuardWire catheter. Patients with coronary slow-flow/no-reflow were 3, 2 and 0 cases in Group D, Group R / T and Group P, respectively. In the present study, patients with good-reflow were enrolled in order to investigate the coronary microcirculation disorder in patients with visually similar coronary blood flow obtained in coronary angiography after percutaneous coronary reperfusion therapy. TF myocardial scintigraphy was performed 10+/-3 days after admission. Bull's eye images were divided into 8 sections, and each section was evaluated in 4 grades. The grade of each segment was regarded as the defect score. The results were compared with the database prepared based on bull's eye maps from 50 healthy adults in our hospital, and count areas of -2 x SD (standard deviation) or less were calculated as the extent score (%), reflecting the area in which myocardial blood flow was decreased. The extent and severity scores in Groups P and R/T were significantly lower than those in Group D. Coronary angiography at the chronic stage (6 months after surgery) showed the patency of the responsible vascular lesion in all patients. However, the ANP, BNP, cardiac index, and pulmonary capillary wedge pressure (PCWP) were significantly improved in Groups R/T and P, compared to Group D (p<0.01). These results suggest that the use of a RESCUE/Thrombuster system and a PercuSurge GuardWire catheter system in patients with acute inferior wall infarction improves coronary microcirculation disorders and acute- to chronic-phase cardiac function.

Aged↗