A sensitive assay for the enzymatic activity of GTP cyclohydrolase I.
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Animals↗
Biomedical subjects
K Hatakeyama
Publications and source records attributed to K Hatakeyama.
Novel S100 proteins in human esophageal epithelial cells: CAAF1 expression is associated with cell growth arrest.
CAAF1 and CAAF2, newly identified calcium-binding proteins from bovine amniotic fluid, have been revealed to be members of the S100 protein family preferentially produced by fetal squamous epithelial cells, including epidermal keratinocytes. Having previously cloned the cDNA of human CAAF1 protein from the esophageal epithelium, we report here on the characteristic expression pattern of CAAF1 and related S100 proteins in human esophageal epithelial cells. Normal cells of the human esophageal epithelium expressed CAAF1, and also expressed the homologous novel S100 proteins including CAAF2, MRP8, and MRP14, but not S100alpha. An immunohistochemical study with specific monoclonal antibodies against CAAF1 proteins demonstrated that CAAF1 proteins were produced by the esophageal epithelial cells in the process of cell differentiation. The immature proliferating cells in the epithelium did not produce CAAF1 proteins, but the differentiated cells expressed CAAF1, which overlay the immature cells and were stratifying in the epithelium. These CAA 1-producing cells did not show any proliferating activities. Esophageal carcinoma cells did not express CAAF1, except for the keratinized cells with no proliferating activity. In addition, the forced expression of CAAF1 proteins in the carcinoma cells resulted in a marked decrease in DNA synthesis. These findings indicate that human esophageal epithelial cells express the multiple genes of S100 proteins including CAAF proteins, and that CAAF1 is closely associated with the terminal differentiation of these cells. CAAF1 expression also might play some role in cell growth.
Amino Acid Sequence↗
The role of tissue factor in the pathogenesis of thrombosis and atherosclerosis.
TF is a major regulator of coagulation and hemostasis. High levels of TF antigen and activity are detected in atherosclerotic lesions, particularly in the advanced lesions. When the plaques are ruptured or eroded, exposure of cellular and extracellular TF to circulating blood play a pivotal role in mediating fibrin-rich thrombus formation leading to acute coronary syndromes. On the other hand, activation of blood coagulation and deficiency of coagulation inhibitors, without endothelial cell denudation, are considered to be an important factor of thrombogenesis in the microcirculation. The imbalance between TF and TFPI seems to be important in promoting fibrin thrombus formation in the lung of endotoxin induced DIC condition.
Animals↗
[Electrophysiologic evaluation of passive and active attentions--I. Topographic analysis of somatosensory event-related potentials].
We studied the topography of somatosensory event-related potentials (SERP) in two different attentive conditions: passive and active. Seventeen healthy right-handed young men, aged 19 to 28 years old (average age; 22.9 years), were requested to perform the following four paradigms in turn. In the passive attentive paradigm, participants were given no specific task when 0.3 Hz electrical stimuli were at random delivered to the right median nerve. In the active attentive paradigm, subjects were required to direct their attention to the regular 0.3 Hz stimuli with all their might. In the control paradigm. 2.0 Hz stimuli were delivered as they listened to their favorite music. Finally, in the oddball paradigm, subjects were instructed to push a button whenever they detected rare stimuli. SERP was recorded at 13 electrodes Grand average topographic amplitude maps from the individual data of the seventeen subjects were made at the latencies of N 60, P 90, N 130 and P 250 for each of the four paradigms. The topographic maps of P 250, the largest positive peak between 200 and 300 msec after the stimuli, showed a significant difference in the distribution of amplitude in the passive and active attentive paradigms compared to the control paradigm. A statistically significant enhancement was noted at the central region in the passive attention, and at the central and frontal regions in the active attention. These results suggest that P 250 consists of two attentive components distinct from selective or discriminative attention. The enhanced positivity at the frontal region during active attention may be associated with expecting the next stimulus and maintaining awareness.
Adult↗
[Electrophysiologic evaluation of passive and active attentions--II. Developmental changes of somatosensory event-related potentials in different attentive paradigms].
By somatosensory event-related potentials (SERP) we have previously demonstrated in adults that an enhanced positivity of P 250 is statistically significant at the frontal region during the active attentive state. We have also evaluated developmental changes of P 250 during different attentive states: passive and active. In this study, 30 healthy children (5-16 years of age) and six healthy adults (23-41 years) were required to perform the following four paradigms: passive attentive, active attentive, control, and oddball. SERP were recorded at Fz, Cz and Pz. In the passive attentive paradigm, P250 amplitude at Fz, Cz and Pz remained constant irrespective of age. With regard to the topography of the amplitude, however, P 250 was distributed dominantly at Pz in Group 1 (5-6 years of age) and Group 2 (7-11 years), contrary to the dominance at Cz in both Group 3 (12-16 years) and adults. In the active attentive paradigm, on the other hand, the P 250 amplitude at Fz reached its minimum at about 10 years and then increased until the adulthood. With respect to the topography of the amplitude, P 250 was distributed dominantly at Pz in Groups 1 and 2, at Cz in Group 3, and at Fz and Cz in adults. These results suggest that the topographic changes in the active attentive paradigm are dependent upon the developing abilities to expect the next stimulus and to maintain awareness.
Adolescent↗
Early intraperitoneal dissemination after radical resection of unsuspected gallbladder carcinoma following laparoscopic cholecystectomy.
We describe a case of early intraperitoneal dissemination after a radical second operation following laparoscopic cholecystectomy for unsuspected locally advanced carcinoma of the gallbladder. A radical procedure including wedge resection of the gallbladder bed, resection of the extrahepatic bile ducts, and dissection of the regional nodes and interaortocaval nodes was performed 17 days after laparoscopic cholecystectomy in a 60-year-old woman. The final histologic examination revealed a moderately differentiated adenocarcinoma invading perimuscular connective tissue with one positive pericholedochal node (pT2, pN1, pM0). Despite the absence of intraperitoneal dissemination at reexploration, the patient had intraperitoneal dissemination 5 months after the second operation. Insidious intraperitoneal dissemination may decrease the survival rate of locally advanced carcinoma of the gallbladder after laparoscopic cholecystectomy compared with open cholecystectomy. Surgeons should search for unsuspected carcinoma of the gallbladder intraoperatively to avoid implantation metastasis.
Adenocarcinoma↗
Mutations of p53 in gallbladder carcinomas in high-incidence areas of Japan and Chile.
Gallbladder adenocarcinomas from patients in two high-prevalence areas, Niigata (Japan) and Santiago (Chile), were analyzed for acquired mutations in exons 5-8 of the p53 tumor suppressor gene, and the characteristics of p53 alterations in the two groups were compared. Of 42 tumors, 22 (52.4%) harbored 25 alterations identified by PCR amplification and direct sequencing (13 of 22 tumors from Niigata and 12 of 20 tumors from Santiago). All alterations were single base pair substitutions, 20 (80%) leading to an amino acid substitution or a chain-termination signal, and 5 (20%) were silent. Immunohistochemically, 55 of 84 cases (65.5%) showed overexpression of p53 protein, with no significant difference in frequency between the two areas. Missense mutations correlated highly with overexpression of the p53 protein (93.4%). Mutations of p53 occurred in all four exons examined, most commonly in exon 5, but in no particular "hot spot." In base-change spectra, all 12 mutations from Santiago showed transitions, with 4 arising at the CpG dinucleotide (33.3%). In contrast, no such transition was found at CpG sites in Niigata, and 4 of 13 mutations (30.8%) were transversions. The data indicated that p53 mutations are highly important in carcinogenesis in the gallbladder. In addition, the difference in p53 mutational spectra in Niigata and Santiago indicate a likely regional difference in mutagenesis.
Adult↗
[Methods of measuring telomere length and telomerase activity--practice and problems].
The development of a highly sensitive method for detection of telomerase activity, telomeric repeat amplification protocol (TRAP), has provided knowledge on telomerase activity in normal and cancer tissues. Subsequent several modifications have been achieved, including an introduction of the internal standard and hybridization protection technique that leads to simplicity and improvement of reproducibility and linearity of this method, and application of TRAP to in situ analysis to identify the cells responsible for telomerase activity. As for measurement of telomere length, fluorescence in situ hybridization technique appeared to give an information of telomere length on an individual chromosome in contrast to analysis of terminal restriction fragment, a conventional method which can express mean telomere length of all chromosomes. Further methodological improvement in this field is ongoing and showing a new sight on cell mortality and immortality.
Humans↗
Tumor recurrence in patients with early gastric cancer: a clinicopathologic evaluation.
We conducted a retrospective study on 711 patients with early gastric cancer. Twenty-two patients (4.0%) developed recurrent disease and 21 died of recurrence during this study. One hundred and sixty-three patients died of unrelated or unknown causes. The recurrence patterns of 22 patients were as follows: hematogeneous metastasis to the liver in 11 patients, peritoneal dissemination in 3, recurrence in the remnant stomach in 3, and in the distant lymphonodes in 1. The mean survival period of patients with recurrent disease was 50.4 months, and 7 of these patients (31.8%) died more than 5 years after surgery. A retrospective clinicopathologic evaluation of the 22 patients and 526 patients without recurrence revealed significant differences between the two groups with respect to mean age at the time of surgery (62.5 years in the recurrent group vs 57.3 years in the nonrecurrent group), tumor size (41.2 vs 30.6 mm), depth of invasion (submucosal cancer: 19 vs 256), lymphnode metastasis (11 vs 48), lymphatic (11 vs 89) and venous (7 vs 18) invasion, and operative curability (curability B: 8 vs 48). Three patients with intramucosal cancer who died of hematogenous and/or peritoneal recurrence within 7 years after surgery had neither lymphnode metastasis nor lymphatic or venous invasion, suggesting that new techniques are needed for prediction of recurrent disease in patient with early gastric cancer.
Adult↗
Fibrin-rich and platelet-rich thrombus formation on neointima: recombinant tissue factor pathway inhibitor prevents fibrin formation and neointimal development following repeated balloon injury of rabbit aorta.
Thrombus formation and neointimal growth are the critical events in restenosis after balloon angioplasty. However, the responses of diseased vessels to injuries caused by balloon angioplasty have not been well examined. We investigated the thrombus formation and neointimal development following the balloon injury to the previously induced neointima in the rabbit aorta and the effects of recombinant tissue factor pathway inhibitor (rTFPI) on these responses. Rabbit thoracic aortas were subjected to injury with a Fogarty 4F balloon catheter at 1.75 atm (first injury), and 4 weeks later the same vessels were subjected to the second injury with a Swan-Ganz 5F balloon catheter at 1.4 atm (mild-injury group) or 1.8 atm (severe-injury group), and immediately after that a retrograde bolus injection of rTFPI (100 microg/kg body weight) or saline was performed into the injured segments via the central tube of the Swan-Ganz catheter. Twenty minutes after the second injury, the injured surfaces were covered with platelet-rich thrombi in the mild-injury group and with fibrin-rich thrombi in the severe-injury group. Damaged intimal smooth muscle cells, which were immunohistochemically positive for tissue factor (TF), were observed beneath the fibrin-rich thrombi. The neointima 4 weeks after the second injury was significantly thicker in the severe-injury group than in the mild-injury group. The bolus infusion of rTFPI markedly inhibited fibrin formation on the injured surfaces, and significantly reduced the neointimal development in the severe-injury group at 4 weeks after the second injury. These results indicate that TF-dependent coagulation pathway is primarily responsible for fibrin-rich thrombus formation and may play an important role in neointimal development following the balloon injury to the rabbit aortic neointima. Additionally the bolus administration of rTFPI to the injured vessels could prevent mural thrombus formation and neointimal growth after balloon angioplasty.
Animals↗
[Genetic alterations in gallbladder carcinoma: a review].
Earlier evidence suggests that gallbladder carcinoma (GBC) has three carcinogenic pathways; de novo development; adenoma-carcinoma sequence; and hyperplasia-carcinoma sequence associated with an anomalous arrangement of the pancreaticobiliary duct (AAPBD). We review gene abnormalities in GBC reported to date. p53 mutation and its protein overexpression are frequently observed in de novo carcinoma and GBC with AAPBD, but never found in carcinoma with adenoma. The incidence of K-ras codon 12 mutation in GBCs with AAPBD is significantly higher than that in the other types. Mutation of K-ras is never detected in carcinoma with adenoma. These findings suggest that diverse genetic pathways may exist in gallbladder carcinogenesis and reflect morphologic variations.
Adenoma↗
Molecular cloning of a new aquaporin from rat pancreas and liver.
A new water channel (aquaporin-8, gene symbol AQP8) was isolated from rat pancreas and liver by homology cloning. Ribonuclease protection assay showed intense expression of the gene in pancreas and liver, less intense in colon and salivary gland, and negligible in other organs. The full-length cDNA was obtained by ligation of approximately 1.4-kilobase (kb) cDNA isolated from the rat liver cDNA library to approximately 0.5 kb of the 5'-end fragment obtained by the rapid amplification of cDNA ends method. A major transcript of approximately 1.45 kb was demonstrated in liver and colon by Northern blot analysis. Expression of the cRNA in Xenopus oocytes markedly enhanced osmotic water permeability in a mercury-sensitive manner, indicating a water channel function of this molecule. The open reading frame encoded a 263-amino acid protein with a predicted molecular size of 28 kDa. Hydropathy analysis represented six membrane-spanning domains and five connecting loops containing two sites of NPA motif as preserved in other aquaporins. Unlike other mammalian aquaporins, AQP8 has an unusual structure with a long N terminus and a short C terminus, which are found in plant aquaporin, gamma-tonoplast intrinsic protein. By in situ hybridization, AQP8 mRNA expression was assumed in hepatocytes, acinal cells of pancreas and salivary gland, and absorptive colonic epithelial cells. The physiological role(s) of AQP8 remain to be elucidated.
Amino Acid Sequence↗
Combined pancreaticoduodenectomy and hepatectomy for patients with locally advanced gallbladder carcinoma: long term results.
BACKGROUND: The objective of this study was to evaluate the efficacy of combined pancreaticoduodenectomy and hepatectomy for the treatment of patients with locally advanced gallbladder carcinoma. METHODS: Long term results over 5 years of follow-up were analyzed retrospectively in 17 consecutive patients with gallbladder carcinoma who underwent combined pancreaticoduodenectomy and hepatectomy with radical lymphadenectomy. The indications for pancreaticoduodenectomy were direct invasion of the adjacent organs (stomach, duodenum, or pancreas) and/or the presence of peripancreatic (head only) lymph node metastases. The hepatectomy performed was a nonanatomic resection of the gallbladder bed in 15 patients and an extended right hepatectomy in 2 patients. There was 1 in-hospital death (6%). RESULTS: Overall, 5 patients (29%) survived 5 years after surgery. Of these patients, four had Stage IVB disease with positive peripancreatic lymph nodes. Eight of the 10 patients who underwent a potentially curative resection survived longer than 3 years, whereas none of the 7 patients with residual tumor survived beyond 15 months. The 5-year survival of 50% (median survival: 58.5 months) in those undergoing a potentially curative resection was significantly better than the 5-year survival of 0% (median survival: 8 months) observed in those patients with residual tumor (P = 0.00086). CONCLUSIONS: Combined pancreaticoduodenectomy and hepatectomy is an efficacious treatment for patients with locally advanced gallbladder carcinoma, but only if a potentially curative resection is feasible. The presence of peripancreatic (head only) lymph node disease is not a contraindication for this procedure.
Adenocarcinoma↗
Gene cloning and characterization of maleate cis-trans isomerase from Alcaligenes faecalis.
Maleate cis-trans isomerase, which catalyses the conversion of maleate to fumarate, was purified and characterized from Alcaligenes faecalis IFO13111. The molecular weight of maleate isomerase was estimated as 60 kDa, consisting of a 28 kDa dimer as shown by gel-filtration chromatography and SDS-PAGE analysis. Kinetic studies showed that the Michaelis constant for maleate was 4.0 x 10(-5) M. The reverse reaction (fumarate to maleate) activity of the enzyme was detected even though it was quite weak. The maleate isomerase gene (maiA) was cloned by hybridization using the oligonucleotide DNA probes designed on the basis of the determined N-terminal amino acid sequences of the purified enzyme. The determined DNA sequence of the maiA gene contains an open reading frame which encodes a 254-amino-acid sequence. The amino acid sequence of the maiA gene product shows no significant homology to any amino acid sequences in the protein data base.
Alcaligenes↗
Analysis of tissue factor and tissue factor pathway inhibitor expression in human colorectal carcinoma cell lines and metastatic sublines to the liver.
To investigate the expression of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in human colorectal carcinomas, Northern blot analysis was performed in a series of human colorectal carcinoma cell lines and in normal or tumoral colorectal tissues. Of 16 human colorectal carcinoma cell lines examined, most expressed TF mRNA, though the levels of expression varied significantly. Considerably higher expression was observed in the cell line CaR-1, while lines established from metastatic lesions tended to express abundant TF mRNA. By contrast, TFPI mRNA levels were low in these high TF-expressing cell lines. TFPI was expressed abundantly in WiDr and in a few other cell lines which expressed a very low level of TF mRNA. Immunocytochemically, both proteins were stained predominantly on the cell surface; however, diffuse cytoplasmic staining for TF also was observed in CaR-1 cells. In addition, the cell surface TF activity was significantly higher in CaR-1 cells than in WiDr cells, confirming the results of mRNA analysis. The level of TF mRNA in colorectal carcinoma tissue in vivo and its ratio to the normal counterpart also varied significantly among the cases. To search for a possible role of TF/TFPI in metastasis of colorectal carcinoma cells, the expression of these genes was compared between a rectal adenocarcinoma cell line, RCM-1, and its highly metastatic subline, RCM-1 L-10. Compared with the parent line, RCM-1 L-10 expressed 7.5-fold higher levels of TF mRNA, whereas TFPI expression was not altered significantly or even decreased slightly. The higher cellular TF activity was confirmed in the metastatic subline in comparison with the parent line.
Adenocarcinoma↗
Lymph node spread from carcinoma of the gallbladder.
BACKGROUND: Lymph node spread is the most common pattern of progression in gallbladder carcinoma (GBC) and is a prognostic factor. The purpose of this study was to determine the prevalence of lymph node metastases in patients with resected advanced GBC, and to evaluate the curative effects of radical surgery for patients with lymph node metastasis. METHODS: One hundred and eleven consecutive patients who had undergone radical surgery for GBC were included in this study. The pattern of lymph node metastases was examined histopathologically, using the TNM staging of the American Joint Committee on Cancer. RESULTS: There was no neurovascular invasion or lymph node involvement in 15 patients with pT1 tumors. Sixty of 96 patients with pT2-4 tumors had lymph node metastases. The pericholedochal lymph node was the most common metastatic lymph node, followed by the cystic lymph node. The frequency of metastases in retroportal, posterosuperior pancreaticoduodenal, and interaorticocaval lymph nodes was >15% in all cases. pT3-4 tumors had significantly more lymph node involvement (79%) and significantly higher N2:N1 ratios (2.5) than pT2 tumors (46% and 0.6, respectively). There was no difference in 5-year survival between N0 and N1 groups in pT2-4 tumors (66% in N0 and 53% in N1). Patients with N2 disease had a significantly worse prognosis, but 4 patients survived >5 years. CONCLUSIONS: The cystic and pericholedochal lymph nodes are the initial site of spread from GBC. The frequency of lymph node involvement is strongly influenced by the depth of invasion of the primary tumor. GBC limited to such lymph node metastases can be cured by surgery in >50% of such cases.
Adenocarcinoma↗
Cloning, sequencing, and characterization of the ftsZ gene from coryneform bacteria.
Taking advantage of highly conserved domains present in the ftsZ genes from Escherichia coli, Rhizobium meliloti, and Bacillus subtilis, we designed degenerate oligonucleotides (oligos) corresponding to these regions. These oligos were used as primers in PCR in order to amplify DNA sequences from Brevibacterium flavum MJ233 chromosomal DNA. The PCR product was used as a probe to recover genomic fragments from a lambda library of Br. flavum MJ233. The complete nucleotide sequence (nt) of the cloned 4.2-kb EcoRI fragment containing the ftsZ homolog from Br. flavum MJ233 indicated that the deduced gene product of the Br. flavum ftsZ homolog is composed of 438 amino acids (aa) with a deduced molecular weight of 46.9 kDa. This size of molecular weight was also confirmed by the in vitro protein synthesis assay. Comparison of this aa sequence to the corresponding sequences from E. coli, Rh. meliloti, B. subtilis, and Streptomyces coelicolor revealed a high degree of conservation and suggested that the Br. flavum ftsZ homolog has a putative GTP binding motif and a GTP hydrolizing region. Expression of Br. flavum ftsZ gene in E. coli, JM109 inhibited its cell division, leading to filamentation. This suggested that the Br. flavum ftsZ product competed with the E. coli ftsZ product.
Amino Acid Sequence↗
Novel genes encoding 2-aminophenol 1,6-dioxygenase from Pseudomonas species AP-3 growing on 2-aminophenol and catalytic properties of the purified enzyme.
2-Aminophenol 1,6-dioxygenase was purified from the cell extracts of Pseudomonas sp. AP-3 grown on 2-aminophenol. The product from 2-aminophenol by catalysis of the purified enzyme was identified as 2-aminomuconic 6-semialdehyde by gas chromatographic and mass spectrometric analyses. The molecular mass of the native enzyme was 140 kDa based on gel filtration. It was dissociated into molecular mass subunits of 32 (alpha-subunit) and 40 kDa (beta-subunit) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that the dioxygenase was a heterotetramer of alpha2beta2. The genes coding for the alpha- and beta-subunits of the enzyme were cloned and sequenced. Open reading frames of the genes (amnA and amnB) were 816 and 918 base pairs in length, respectively. The amino acid sequences predicted from the open reading frames of amnA and amnB corresponded to the NH2-terminal amino acid sequences of the alpha-subunit (AmnA) and beta-subunit (AmnB), respectively. The deduced amino acid sequences of AmnB showed identities to some extent with HpaD (25.4%) and HpcB (24.4%) that are homoprotocatechuate 2,3-dioxygenases from Escherichia coli W and C, respectively, belonging to class III in the extradiol dioxygenases. On the other hand, AmnA had identity (23.3%) with only AmnB among the enzymes examined.
Amino Acid Sequence↗