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A Kuroda

Publications and source records attributed to A Kuroda.

At least 19 recordsLinked to original sources
PubMed1992

Characterization of the Bacillus subtilis CwbA protein which stimulates cell wall lytic amidases.

The Bacillus subtilis cell wall binding protein, CwbA, stimulated the cell wall lytic activities of the B. subtilis and B. licheniformis autolysins (CwlA and CwlM, respectively) in addition to that of the major B. subtilis autolysin (CwlB). Even though the substrate for the enzyme reaction was changed from B. subtilis cell wall containing a teichoic acid to Micrococcus luteus cell wall containing a teichuronic acid, the stimulatory effect of CwbA on CwlA activity was observed.

Bacillus subtilis↗
PubMed1992

Genetic structure, isolation and characterization of a Bacillus licheniformis cell wall hydrolase.

A DNA fragment containing the gene for a cell wall hydrolase of Bacillus licheniformis was cloned into Escherichia coli. Sequencing of the fragment showed the presence of an open reading frame which encodes a polypeptide of 253 amino acids with a molecular mass of 27,513. The gene was designated as cwlM, for cell wall lysis. The deduced amino acid sequence indicated that there is a repeated sequence consisting of 33 amino acid residues in the C-terminal region. Deletion of the C-terminal region did not lead to any loss of cell wall lytic activity. The gene product purified from E. coli cells harboring a cwlM-bearing plasmid exhibited a M(r) value of 29 kDa on SDS-polyacrylamide gels, and characterization of the specific substrate bond cleaved by CWLM indicated that the enzyme is an N-acetylmuramoyl-L-alanine amidase (EC 3.5.1.28). The enzyme hydrolyzed the cell wall of Micrococcus luteus more efficiently than those of B. licheniformis and B. subtilis, but the truncated CWLM (lacking the C-terminal region) had lost this preference. CWLM prepared from B. subtilis cells harboring a plasmid containing cwlM had a similar M(r) value to that from E. coli. Amino acid sequence homologies between CWLM and other amidases, and their protein structures are discussed.

Amino Acid Sequence↗
PubMed1992

Molecular cloning and sequencing of the upstream region of the major Bacillus subtilis autolysin gene: a modifier protein exhibiting sequence homology to the major autolysin and the spoIID product.

The upstream region of the N-acetylmuramoyl-L-alanine amidase gene (cwlB; a major Bacillus subtilis autolysin) was cloned into Escherichia coli by chromosome walking. Sequencing of the region showed the presence of two open reading frames, one (designated as cwbA) which starts at a UUG codon and encodes a polypeptide of 705 amino acids with an M(r) of 76,725, and the other (designated as lppX), upstream of cwbA, comprising 102 amino acids and having a signal sequence characteristic of a lipoprotein. Purification of the CwbA protein and determination of its N-terminal amino acid sequence revealed that it contains a presumed signal peptide which is processed after Ala at position 25 from the N-terminal, and that the M(r) of the mature form is 75,000. The amino acid sequences of the N-terminal and C-terminal regions of CwbA were found to be highly homologous with those of the cell wall binding domain of CwlB and the spoIID gene product, respectively. CwbA stimulated the major autolysin activity approximately threefold in vitro. These data indicate that CwbA is the modifier protein of the major autolysin reported by Herbold, D. R. & Glaser, L. (1975; Journal of Biological Chemistry 250, 1676-1682). In-frame fusion between the lppX and lacZ genes demonstrated that lppX is translated in vivo and expressed during the exponential growth phase.

Amino Acid Sequence↗
PubMed1992

No significant correlation between histologic changes of the papilla of Vater and juxtapapillary diverticulum. Special reference to the pathogenesis of gallstones.

The aim of this study was to investigate the significance of histologic changes of the papilla of Vater in cases with a juxtapapillary diverticulum, with special reference to the pathogenesis of gallstones. Three hundred and sixty-two autopsy cases, mainly of aged people, were analyzed. The incidence of both diverticulum and gallstone increased with age. The presence of diverticulum was associated with a significant increase of gallstones (49% versus 20%; P < 0.01). Analysis by the type of gallstones showed a significantly higher incidence of bilirubinate in cases with juxtapapillary diverticula. Stones both in the gallbladder and in the extrahepatic bile ducts were more prevalent in cases with diverticula as compared with the cases without diverticula. No significant relationship was found between juxtapapillary diverticula and the degree of histologic changes in the papilla of Vater, such as inflammatory cellular infiltration, fibrous proliferation, glandular proliferation, or muscular hypertrophy and proliferation of the sphincter of Oddi. These facts imply that juxtapapillary diverticula are not involved in the formation of gallstones via histologic changes of the papilla of Vater, whereas diverticula may play an important role in the pathogenesis of gallstones, especially of bilirubin stones.

Aged↗
PubMed1992

[Small cell carcinoma of urinary bladder. A case report].

A 57-year-old male patient was admitted because of a severe lumbar pain and gross hematuria. The rectal examination revealed a fist-sized soft tissue mass in the small pelvic space. A huge non-papillary tumor, which occupied the intravesical space, was found on cystoscopic examination. CEA IAP, TPA, CA19-9 and NSE were abnormally elevated in the serum. The pelvic CT scan shown an enormous polypoid tumor arising from the anterior vesical wall, while no abnormal lesion was found in the head, neck, chest and abdominal CT scans. The bone scintigraphy revealed multiple abnormal accumulations. The transurethral biopsy of the tumor was carried out. The pathological examination revealed homogeneous and small tumor cells arranged in sheet and solid patterns, which were positive for the anti-NSE stain and anti-NF stain, but negative for Grimelius stain. The final diagnosis was small cell undifferentiated carcinoma of the urinary bladder. The patient died of cancer five months after diagnosis.

Carcinoma, Small Cell↗
PubMed1992

[Surgical and non-surgical treatments of gallstones].

Comparisons were made of therapeutic modalities for gallstones. Four-hundred thirty-five patients with gallstones were operated on with the mortality rate of 0.7%. Extracorporeal shock-wave lithotripsy (ESWL) was performed in 84 patients with gallbladder stones. Complete stone disappearance rate at 1 year was 31% in patients with one to three radio-lucent stones not larger than 3cm in diameter and 57% in solitary stones up to 2cm with the US pattern of Ia or Ib. There was no major complication. Endoscopic sphincterotomy (EST) was performed in 131 patients with common bile duct stones. The success rate was for stone extraction, was 97%. Immediate complications occurred in 8% cases, yielding the mortality rate of 0.8%. Common bile duct stones recurred in 2 of 113 patients (3%). Acute cholecystitis was experienced in 2 of 43 patients with the gallbladder left in situ; 2 of 12 with and none of 31 without gallbladder stones. In conclusion, ESWL is a safe and effective treatment in selected patients. EST can be the first-choice modality in the treatment of not only the post-cholecystectomy cases but also the patients with the gallbladder without stones.

Adult↗
PubMed1992

[Microspectrophotometric analysis of DNA content in duct epithelial proliferation and invasive carcinoma of the pancreas].

Nuclear DNA content of 131 pancreatic duct epithelial lesions, including 10 normal ducts, 30 intraductal proliferations with mild atypia (groups I-II), 30 with moderate atypia (group III), 24 with severe atypia (group IV), 14 of carcinoma in situ (group V), and 23 invasive carcinomas, was analyzed using microspectrophotometry. DNA histograms were classified into diploid, polyploid and aneuploid patterns. All of normal duct epithelia showed diploidy. Polyploid patterns were observed in 3 (10%) lesions of groups I-II, 17 (56.7%) of group III, 14 (58.4%) of group IV, 7 (50%) of group V, and 6 (26.1%) of invasive carcinomas, and aneuploid patterns were observed in 0%, 10%, 33.3%, 50% and 73.9%, respectively. This distribution of ploidy patterns revealed a gradual shift to the main ploidy from diploid to polyploid followed by aneuploid in proportion to the increase of the degree of epithelial atypia. The frequencies of polyploid cells in each lesion were determined. Their averages were 0.2% in groups I-II, 1.9% in group III, 3.4% in group IV, 4.4% in group V, and 6.7% in invasive carcinoma. The S+G2M phase fractions were significantly higher in proliferative epithelia than in normal. The results of this study suggest that duct epithelial proliferations of the pancreas have "genetic instability" leading to a serial clonal evolution and play a significant role in the progression of pancreatic duct cell carcinoma.

Carcinoma in Situ↗
PubMed1991

Purification and characterization of a cell wall hydrolase encoded by the cwlA gene of Bacillus subtilis.

A cell wall hydrolase of Bacillus subtilis was prepared from Escherichia coli cells harboring a plasmid containing the B. subtilis cwlA gene and purified by hydroxyapatite column chromatography and HPLC through TSK-gel G3000SWXL. In contrast to the molecular mass of 29,919 Da deduced from its nucleotide sequence, the purified CWLA is a 23 kDa protein. Characterization of the specific substrate bond cleaved by CWLA indicated the enzyme is an N-acetylmuramyl-L-alanine amidase. A 32-kDa precursor protein was detected on zymography of a crude cell homogenate. Some of the enzymatic properties of CWLA are also described.

Bacillus subtilis↗
PubMed1991

Clinical pathology of endocrine tumors of the pancreas. Analysis of autopsy cases.

A clinicopathological analysis of endocrine tumors of the pancreas, using 800 autopsy cases (422 men, 378 women, mean age 78.7) was accomplished. The results were: (1) Endocrine tumors and similar lesions were found in 3% or 24 cases (25 lesions). Twenty lesions (20 cases) were found to be tumors and five lesions (five cases) were determined to be hyperplasia of Langerhans islets. (2) Incidence of tumor was 10% (6/60) in individuals having histological studies of all sections of the pancreas, and 1.6% (12/738) in individuals having histological studies of three random sections of the pancreas. (3) None of the cases with tumors and hyperplastic lesions showed symptoms of hormone production. (4) Immunohistochemical analysis revealed hormone production in all 20 tumor cases and multiple hormone production was found in 14 of these (70%). (5) Ductular or tubular structures were found in or adjacent to the tumors in 12 cases (60%) and hyperplasia in one case (20%). Langerhans islets, 500 microns or larger in size, were found in three lesions of the tumor (15%). Langerhans islets with the mean diameter of normal islets + 2 SD or larger also were found around five tumors (25%) and three hyperplasias (60%). The above findings suggest that endocrine tumors of the pancreas are prevalent and that they do not produce symptoms of excessive hormone production even though they do continue to produce hormones. Some of the endocrine tumors or hyperplasias develop from totipotent stem cells of the duct epithelia, and factors promoting the growth of Langerhans islets might exist.

Aged↗
PubMed1991

Characterisation of beta 1 and beta 2 adrenoceptor subtypes in the atrioventricular node of diabetic rat hearts by quantitative autoradiography.

STUDY OBJECT: The aim was to determine whether the changes in beta adrenoceptors might be involved in the conduction system of diabetic rat hearts. DESIGN: beta Adrenoceptors in the atrioventricular node of diabetic hearts and controls were characterised by quantitative autoradiography. EXPERIMENTAL MATERIAL: The experiments were performed in five male Wistar rats injected with streptozotocin (65 mg.kg-1) to induce diabetes and in five rats injected with vehicle alone. MEASUREMENTS AND MAIN RESULTS: 125I-iodocyanopindolol binding sites decreased by 25% in atrioventricular node of diabetic hearts compared to control hearts without a significant change in the affinity. The selective beta 1 adrenoceptor antagonist CGP20712A (100 nmol.litre-1) displaced about 30% and 50% of the total atrioventricular node binding sites in diabetic and control hearts, respectively. CONCLUSIONS: These data support the concept that a decrease in beta adrenoceptors, mainly of the beta 1 subtype, in the atrioventricular node may play an important role in the cardiac conduction disturbance of diabetic animals.

Animals↗
PubMed1991

Immunohistochemical study of the distribution of pancreastatin in endocrine tumors of the pancreas and in normal pancreatic tissue: analysis of autopsy cases.

Using sixteen cases (sixteen lesions) of endocrine tumor of the pancreas, found in 1,300 consecutive autopsy cases (661 men and 639 women; mean age, 79.0 years), we examined distribution patterns of pancreastatin (PST) in these endocrine tumors and in normal tissues around them, using immunohistochemical staining. In addition, the distribution patterns of PST was compared with those of insulin (INS), glucagon (GLU), somatostatin (SOM), and pancreatic polypeptide (PP), in these tissues. Normal islets of Langerhans were stained completely and evenly for PST. Two endocrine tumors did not stain for PST at all, six were partially stained, and eight were stained as densely as normal islets, or even more densely. Acinar cells were only partially stained for PST in 11 cases and showed scattered staining in three cases. Epithelial cells of ducts or ductuli were partially stained for PST in 10 cases and showed scattered staining in three cases. Distribution patterns of PST coincided with that of INS in 56% (9/16) of cases, GLU in 81% (13/16), SOM in 31% (5/16), and PP in 31% (5/16). In the eight tumors that were stained at least as densely for PST as normal islets, the staining pattern did not coincide with that of INS in any case (0%), coincided with that of GLU in all 8 cases (100%), and coincided with those of SOM and PP in one case each (13%). Therefore, the distribution of GLU-producing cells (A cells) coincided most closely with that of PST. It is concluded that most PST is secreted from A cells in human pancreas.

Adenoma, Islet Cell↗
PubMed1991

Molecular cloning and sequencing of a major Bacillus subtilis autolysin gene.

A major Bacillus subtilis 168S autolysin (N-acetylmuramoyl-L-alanine amidase [EC 3.5.1.28]) was purified and then cleaved with cyanogen bromide. The N-terminal amino acid sequence of one of the resultant peptides was determined in order to make synthetic oligonucleotides. A 2.5-kb EcoRI fragment was cloned into Escherichia coli JM109 and detected by colony hybridization by using the oligonucleotides as probes. Sequencing of the insert showed the presence of an open reading frame (designated cwlB), starting at a UUG codon, which encodes a polypeptide of 496 amino acids with a molecular mass of 52,623 Da. CWLB had a presumed signal peptide which is processed after Ala at position 24. Insertional inactivation of the cwlB gene of the B. subtilis chromosome led to an approximately 90% decrease in the total cell wall hydrolytic activity of stationary-phase cells and extraordinary resistance to cell lysis, even after 6 days of incubation at 37 degrees C. No apparent changes in cell morphology, motility, competence, sporulation, or germination were observed.

Amino Acid Sequence↗
PubMed1991

[A case of malignant pheochromocytoma of the urinary bladder].

A 31-year-old man was admitted to our hospital because of miction pain and gross hematuria in August, 1988. Cystoscopic examination revealed a solid mass in the bladder. The histological diagnosis was pheochromocytoma of urinary bladder by biopsy. He had a history of syncope on urination several times. Abnormal elevation of serum noradrenaline was observed in hormonal studies and abnormal accumulation was seen in the bladder by 131I-MIBG scintigraphy. Total cystectomy, lymphadenectomy and urinary diversion were performed in November, 1988. Pathological diagnosis was pheochromocytoma of the urinary bladder with metastasis to both iliac lymph nodes.

3-Iodobenzylguanidine↗
PubMed1990

Massive pancreatic pleural effusion: pathogenesis of pancreatic duct disruption.

Massive pancreatic pleural effusion is believed to be caused by pancreatic duct disruption. To elucidate the cause of the duct disruption, pancreas specimens resected from three cases of massive pancreatic pleural effusion were investigated histopathologically. There was no evidence of either chronic or acute pancreatitis except focal fibrosis along a single dilated duct in the resected pancreas. From our study, the pathogenesis of pancreatic duct disruption is suggested as follows: (a) alcohol ingestion can induce focal acute inflammation on a single branch of the duct system and elicit protein plug formation; and (b) focal stenotic change occurs on this branch at a point near the main pancreatic duct, and transient obstruction can occur by means of the protein plugs. The "upstream" extent of this branch will then dilate until it ruptures. However, on the frequency of this atypical pancreatitis, we have no clues to mention.

Acute Disease↗
PubMed1990

Cloning, sequencing and genetic mapping of a Bacillus subtilis cell wall hydrolase gene.

We have cloned DNA fragments from Bacillus subtilis 168S into Escherichia coli, which produced a lytic zone on an agar medium containing B. subtilis cell wall. Sequencing of the fragments showed the presence of an open reading frame (ORF) which encodes a polypeptide of 272 amino acids with a molecular mass of 29919 Da. The deduced amino acid sequence showed considerable homology with that of the cell wall hydrolase gene of Bacillus sp. (Potvin, C., Leclerc, D., Tremblay, G., Asselin, A. & Bellemare, G. (1988). Molecular and General Genetics 214, 241-248). Accordingly, the gene was designated cwlA, for cell wall lysis. The N-terminal amino acid sequence of cwlA gene product prepared from a E. coli clone was AIKVVKNLVSKSKYGLKCPN, which is consistent with that of the deduced sequence starting from Ala at second position from the initiation codon of the cwlA gene. A presumed sigma A promoter and a rho-independent terminator were found upstream and downstream of the ORF, respectively. A chloramphenicol-resistance determinant integrated into the ORF was mapped by PBS1 transduction, which indicated the gene sequence dnaE-aroD-cwlA.

Amino Acid Sequence↗
PubMed1990

Nucleotide sequences of the Bacillus subtilis flaD locus and a B. licheniformis homologue affecting the autolysin level and flagellation.

A DNA fragment containing the flaD locus of Bacillus subtilis, which had been cloned into plasmid pAC3, was subcloned into an M13 phage and sequenced. The sequence contained five open reading frames (ORFs), of which ORF2 was the flaD gene. Unexpectedly, the sequence of the flaD locus was identical to that of sin [sporulation inhibition gene; Gaur, N. K., Dubnau, E. & Smith, I. (1986). Journal of Bacteriology 168, 860-869]. A B. licheniformis homologue (flaL) of the B. subtilis flaD locus was cloned into pUC19 and identified by colony hybridization. The B. licheniformis DNA was subcloned and sequenced. Two ORFs (ORF1, or L-ORF1; and ORF2, or flaL) were detected, encoding 58 and 111 amino acid residues, respectively. These are almost identical in length to ORF1 (D-ORF1; 57 amino acids) and flaD (111 amino acids) on the fragment of B. subtilis DNA. The overall interspecies differences between the nucleotide sequences of D-ORF1 and L-ORF1, and those of flaD and flaL, were 42% and 11%, respectively, and the differences in the predicted amino acid sequences were 50% and 7%, respectively. The regions 3' of the ORFs (flaL and flaD) in both species resemble rho-independent terminators of transcription. The characteristics of the amino acid sequences are also discussed.

Amino Acid Sequence↗