Biomedical subjects

K Uematsu

Publications and source records attributed to K Uematsu.

At least 19 recordsLinked to original sources

PubMed2002

Localization of group IB phospholipase A(2) isoform in the gills of the red sea bream, Pagrus (Chrysophrys) major.

We previously reported that PLA(2) activity in the gills is higher than that in other tissues in red sea bream and purified PLA(2) from the gills belongs to the group IB PLA(2) as well as other red sea bream PLA(2)s. In this study, we reconfirmed that the level of PLA(2) activity is extremely high in the gills compared with other tissues, and gill PLA(2) was detected only in the gills by immunoblotting and inhibition test using anti-gill PLA(2) monoclonal antibody. The level of PLA(2) activity and protein expression in the gills are well correlated. Fish can be roughly divided into high and low groups based on the level of PLA(2) activity. Gill PLA(2) was detected in the gills of the high group, but not the low group by immunoblotting. In the gills of the high group, gill PLA(2) was detected in the mucous cells and pavement cells located on the surface of gill epithelia by immunohistochemistry. On the other hand, positive signals were observed only in the mucous cells by in situ hybridization. We also isolated inactive proPLA(2), having AR propeptide, preceding the mature enzyme from the gill extract. These results suggest that gill PLA(2) is synthesized as an inactive proPLA(2) in the mucous cells and is secreted to the surface of gill epithelia.

Animals↗

PubMed2002

Extrusion of intracellular calcium ion after in vitro ischemia in the rat hippocampal CA1 region.

Simultaneous recordings of intracellular Ca(2+) ([Ca(2+)](i)) signal and extracellular DC potential were obtained from the CA1 region in 1-[6-amino-2-(5-carboxy-2-oxazolyl)-5-benzofuranyloxy]-2-(2-amino-5-methylphenoxy)-ethane-N,N,N',N'-tetraacetic acid penta-acetoxymethyl ester (Fura-2/AM)-loaded rat hippocampal slices. Superfusion with oxygen- and glucose-deprived medium (in vitro ischemia) for 5-6 min produced a rapid rise of the [Ca(2+)](i) level in the stratum radiatum (rising phase of the [Ca(2+)](i) signal), which occurred simultaneously with a rapid negative DC potential (rapid negative potential). When oxygen and glucose were reintroduced, the increased [Ca(2+)](i) signal diminished rapidly (falling phase of the [Ca(2+)](i) signal) during the generation of a slow negative DC potential (slow negative potential), which occurred within 1 min from the onset of the reintroduction. Thereafter, the [Ca(2+)](i) signal partially and the slow negative potential completely returned to the preexposure level approximately 6 min after the reintroduction. The changes in [Ca(2+)](i) signal during and after in vitro ischemia were very similar to the changes in the membrane potential of glial cells. The rising and falling phases of [Ca(2+)](i) signal corresponded to the rapid depolarization and a depolarizing hump, respectively, in the repolarizing phase of glial cells. A prolonged application of in vitro ischemia or a reintroduction of either glucose or oxygen suppressed the falling phase after ischemic exposure. The application of ouabain (30 microM) generated both a rapid negative potential and a rapid elevation of [Ca(2+)](i), but no slow negative potential or rapid reduction in [Ca(2+)](i) were observed. When oxygen and glucose were reintroduced to slices in the Na(+)-free or ouabain- or Ni(2+)-containing medium, the falling phase was suppressed. The falling phase was significantly accelerated in Ca(2+)- and Mg(2+)-free with EGTA-containing medium. In contrast, the falling phase was significantly slower in the Ca(2+)-free with high Mg(2+)- and EGTA-containing medium. The falling phase of the [Ca(2+)](i) signal after ischemic exposure is thus considered to be primarily dependent on the reactivation of Na(+), K(+)-ATPases, while the extrusion of cytosolic Ca(2+) via the forward-mode operation of Na(+)/Ca(2+) exchangers in glial cells is thought to be directly involved in the rapid reduction of [Ca(2+)](i) after ischemic exposure.

Animals↗

PubMed2001

Aberrations in the fragile histidine triad (FHIT) gene in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) seems to be closely associated with lung carcinogenesis. To identify the genetic characteristics of precancerous IPF lesions in the peripheral lung, we performed PCR-based microsatellite analysis with DNA extracted from microdissected tissues; fluorescent in situ hybridization (FISH) analysis of the fragile histidine triad (FHIT) gene and immunohistochemical analysis of Fhit protein expression in samples of metaplasias and bronchiolar epithelia obtained from patients with IPF. We used four microsatellite markers of the FHIT gene within or flanking the FHIT gene on chromosome 3p for loss of heterozygosity (LOH) analysis. LOH of the FHIT locus was frequently found among the lesions of metaplasias and bronchiolar epithelia in the patients with IPF [62 (52%) of 119 informative lesions]. Fifty-four (73%) of the 74 lesions of metaplasias and bronchiolar epithelia obtained from the IPF patients with lung carcinoma and 8 (17%) of the 46 samples obtained from the IPF patients without lung carcinoma showed LOH at the FHIT gene (P < 0.0001). We confirmed allelic loss in the metaplasias and bronchiolar epithelia of IPF by FISH analysis of the FHIT gene. Additionally, the level of Fhit protein expression in the metaplastic cells of IPF was frequently reduced. Our findings suggest that allelic loss of the FHIT gene may be involved in carcinogenesis in the peripheral lung of patients with IPF.

Acid Anhydride Hydrolases↗

PubMed2001

p14(ARF) modulates the cytolytic effect of ONYX-015 in mesothelioma cells with wild-type p53.

ONYX-015 has been reported to kill selectively tumor cells lacking functional p53. Genetic alterations of INK4a/ARF locus, which is a predominant event in malignant pleural mesothelioma, may result in loss of p14(ARF) and subsequent disruption of p53 pathway in cancer cells. In the present study, ONYX-015 was able to kill three mesothelioma cell lines (H28, H513, and 211H) with wild-type p53 but lacking p14(ARF). In contrast, MS-1 mesothelioma cells, which expressed both p53 and p14(ARF), were resistant to ONYX-015. Introducing p14(ARF) gene into the H28 cell, a mesothelioma cell without p14(ARF) expression, significantly increased the resistance of this cell line to the cytolytic effect of ONYX-015. Our results suggest that human mesotheliomas with wild-type p53 yet lacking p14(ARF) are potential candidates for ONYX-015 therapy.

Adenovirus E1B Proteins↗

PubMed2001

Genomic structure of the human MAD2 gene and mutation analysis in human lung and breast cancers.

Some of the many human cancers that exhibit chromosomal instability also carry mutations in mitotic checkpoint genes and/or reveal reduced expression of some of those genes, such as hMAD2. To facilitate investigation of alterations of hMAD2, we determined its genomic structure and intronic primers designed to amplify the entire coding region. Since general impairment of the mitotic checkpoint is frequently reported in lung cancers, and reduced expression of hMAD2 has been reported in breast cancers as well, we searched for mutations throughout the coding sequence of this gene in the genomic DNA of 30 primary lung tumors, 30 lung-cancer cell lines and 48 primary breast cancers. Our approach, which involved polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing, revealed nucleotide variants in only two of the 108 specimens. One was a cytosine-to-adenine substitution 3 bp upstream of exon 4 that occurred in one lung cancer cell line and one primary breast tumor, a change that did not alter transcriptional sequence. The other was an adenine-to-guanine substitution within exon 4, of the same lung cell line; this change already had been reported as a polymorphism. The results suggested that the hMAD2 gene is not commonly mutated in either lung nor breast cancers. Further studies should focus on other mechanisms that might account for reduced expression of the hMAD2 gene, and/or pursue analyses of other mitotic checkpoint genes for mutations in human cancer. Nevertheless, the genomic structure, the intronic primer sequences, and polymorphisms of the hMAD2 gene presented here will facilitate future studies to determine the full spectrum and frequency of the genetic events that can affect expression of the hMAD2 gene in human tumors.

Breast Neoplasms↗

PubMed2001

Altered expression of several genes in highly metastatic subpopulations of a human pulmonary adenocarcinoma cell line.

Non-small cell lung cancer is associated with approximately 85% mortality due to its high metastatic potential. Therapeutic efforts have failed to produce a significant improvement in prognosis. In this situation, a better understanding of the key factors of metastasis may be useful for designing new molecular targets of therapy. In order to identify these factors, we compared the expression profiles of two subpopulations of an adenocarcinoma cell line with a high metastatic potential, PC9/f9 and PC9/f14, with the parent cell line, PC9, using a cDNA array. The expression of 15 genes was found to be significantly enhanced or reduced in the highly metastatic subpopulations. The expression of matrix metalloproteinase-2 (MMP-2), plasminogen activator inhibitor-1 (PAI-1) and interleukin-1 (IL-1 alpha) were upregulated in the highly metastatic subpopulations, while the expression of carcinoembryonic antigen (CEA), caspase-5, Fas ligand, Prk/FNK, cyclin E, cyclin B1, Ki-67, proliferating cell nuclear antigen (PCNA), Smad4, macrophage proinflammatory human chemokine-3 alpha (MIP-3 alpha)/LARC, Met and CD44 were downregulated. Data from the literature suggest that the altered expression of MMP-2, PAI-1, IL-1 alpha, CEA, caspase-5, Fas ligand, Prk/FNK and Smad4 promotes the highly metastatic phenotype. The differential expression of these genes was confirmed by Northern blot analysis, standard reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR. This analysis in subpopulations of a lung cancer cell line indicated that the highly metastatic potential of lung cancer may be induced not by an alteration in the expression of a single gene, but by the accumulation of alterations in the expression of several genes involved in extracellular matrix (ECM) adhesion disruption, ECM degradation, escape from apoptosis, and resistance to transforming growth factor-beta(1) (TGF-beta(1)). Strategies for inhibiting metastasis of pulmonary adenocarcinoma should be designed accordingly.

Adenocarcinoma↗

PubMed2001

Unchanged frequency of loss of heterozygosity and size of the deleted region at 8p21-23 during metastasis of lung cancer.

The genetic mechanisms involved in lung cancer development and progression are beginning to be understood. Many studies have documented frequent loss of heterozygosity (LOH) at specific chromosomal regions in cancer cells; this implies that tumor suppressor genes (TSG) are usually present in those regions. Recently, it has been reported that LOH or chromosomal deletions at chromosome 8p21-23 represent early events frequently occurring in lung cancer. In addition, the size of these chromosome 8 deletions, as well as their frequency, was also reported to increase during lung cancer progression. To determine the spectrum and frequency of alterations of chromosome 8p21-23 in human lung cancer and whether these increase with progression of the tumors, we performed LOH analysis of chromosome 8p and 3p in the genomic DNA from cells from primary and metastatic sites of lung cancer, as well as from normal lung. We studied 35 subjects with primary lung cancer including 30 tumors with distant metastasis. Detection of allelic deletion utilized a PCR-based approach of microsatellite polymorphism analysis, which was performed using the microsatellite markers D8S1130, D8S1106, D8S511, D8S1827, D8S549, D8S261, LPL, D8S258, D8S136, NEFL, D3S1295, D3S1313, D3S1234, D3S1300, D3S1351, D3S1339, and D3S1340. The overall allelic deletion rates were 10 of 28 (35.7%) at 8p and 13 of 33 (39.4%) at 3p. The allelic deletions in the primary cancer and its metastatic sites were in each case identical in both frequency and size of the deleted regions. In our analysis, 8p21-23 deletions were not always associated with 3p deletions in primary lung cancer. These results therefore suggest that allelic deletion at chromosome 8p21-23 is an early and frequent event in the carcinogenesis and development of lung cancer, independent of chromosome 3p deletion. However, a continuing increase in the frequency of LOH at 8p21-23 and in the size of the deleted region rarely occurs during the process of metastasis.

Adenocarcinoma↗

PubMed2000

Self-augmentation effect of male-specific products on sexually differentiated progesterone metabolism in adult male rat liver microsomes.

It is well known that several 3-keto-4-ene steroids such as progesterone and testosterone are metabolized in a gender-specific or -predominant manner by adult rat liver microsomes. In the male, these steroids are primarily metabolized into two oxidized (16alpha-hydroxyl and 6beta-hydroxyl) products mainly by the respective, male-specific cytochrome P450 subforms, CYP2C11 and CYP3A2, while they are primarily metabolized into the 5alpha-reduced products by female-predominant 5alpha-reductase in the female. These sexually differentiated enzyme activities are largely regulated at the transcription level under endocrine control. In the present study, we show that unlabeled 16alpha-hydroxyprogesterone and 6beta-hydroxyprogesterone inhibited the 5alpha-reductive [(3)H]progesterone metabolism by adult male rat liver microsomes without significantly inhibiting the CYP2C11 and CYP3A2 activities producing themselves, whereas 3alpha-hydroxy-5alpha-pregnan-20-one and 5alpha-pregnane-3,20-dione not only stimulated the 5alpha-reductive metabolism producing themselves but also inhibited the male-specific oxidative metabolism. This finding compels us to propose a novel hypothesis that adult male rat liver microsomes may possess a self-augmentation system regulated by the male-specific products on sexually differentiated steroid metabolism, besides regulation by gene expressions of the related enzymes.

5-alpha-Dihydroprogesterone↗

PubMed2000

The role of oval cells in rat hepatocyte transplantation.

BACKGROUND: Oval cells are liver cells capable of differentiating into either hepatocytes or biliary epithelial cells. We compared growth of hepatocytes and biliary epithelial cells between spleens transplanted with oval cell-free and oval cell-enriched rat liver cells. METHODS: Oval cell-enriched liver cells were obtained from livers of adult rats that had undergone treatment with acetylaminofluorene and partial hepatectomy, although oval cell-free liver cells were obtained from livers of untreated rats. Hepatocyte and biliary epithelial cell growth in the spleen was evaluated by counting periodic acid-Schiff-positive cells and cytokeratin 19-positive cells respectively in sections from transplanted spleens. RESULTS: Spleens transplanted with oval cell-free liver cells and spleens transplanted with oval cell-enriched liver cells contained similar numbers of hepatocytes after 2 weeks. Numbers of hepatocytes in spleens transplanted with oval cell-free liver cells decreased markedly at 4 and 8 weeks, then increasing slightly until 32 weeks. In spleens transplanted with oval cell-enriched liver cells, numbers of hepatocytes decreased only slightly at 4 weeks and then increased markedly. At 4, 8, 12, 16, 24, and 32 weeks, numbers of hepatocytes in spleens transplanted with oval cell-enriched liver cells respectively were 2.3, 3.5, 4.5, 6.7, 6.3, and 15.1 times hepatocyte numbers in spleens transplanted with oval cell-free liver cells. Numbers of biliary epithelial cells in spleens receiving oval cell-enriched liver cells showed changes similar to those in spleens transplanted with oval cell-free liver cells, increasing markedly at 4 weeks and then markedly and rapidly decreasing. CONCLUSIONS: Intrasplenic transplantation of oval cell-enriched liver cells enhanced growth of hepatocytes compared with transplantation of oval cell-free liver cells; this was not true for biliary epithelial cells.

Animals↗

PubMed2000

Somatic mutation of the hBUB1 mitotic checkpoint gene in primary lung cancer.

Mutations in mitotic checkpoint genes have been detected in several human cancers, and these cancers exhibit chromosomal instability. Aneuploid stem cells seem to result from chromosomal instability and have been reported in many lung cancers. To determine whether alteration of mitotic checkpoint regulators is involved in carcinogenesis and tumor progression in primary lung cancer, we screened the genomic DNA sequence of 30 human lung cancer cell lines and 30 primary lung cancer tumors for a mutation in the hBUB1 mitotic checkpoint gene. First, we designed 26 sets of intron-based primers to amplify each of the 25 exons of the hBUB1 gene to examine the entire coding region of the hBUB1 gene. Using these primers, we performed polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis as well as direct sequencing in the mutation analysis of the hBUB1 gene. Three different nucleotide substitutions were detected in the coding region of the hBUB1 gene in some of the cancer cell lines and primary tumors as follows. The hBUB1 gene of one adenocarcinoma tumor contained a somatic missense mutation, a cytosine-to-guanine substitution in codon 51 of exon 5 that resulted in a histidine-to-aspartic acid amino acid substitution. The hBUB1 gene of three lung cancer cell lines contained a thymine-to-cytosine substitution in codon 430 of exon 12, which did not result in an amino-acid substitution. We were unable to determine whether the nucleotide substitution in exon 12 was a polymorphism or a silent mutation because matched normal tissue was not available. A polymorphism in codon 93 of exon 4, a guanine-to-thymine substitution, in hBUB1 was found in one lung cancer cell line and one primary lung tumor. This is the first report of a somatic missense mutation of a gene involved in a mitotic checkpoint in primary lung cancer. The presence of a point mutation in the hBUB1 gene is consistent with the hypothesis that alteration of mitotic checkpoint genes is involved in the development of primary lung cancers. Because the frequency of hBUB1 gene mutations was low, future studies should focus on other mechanisms of inactivation of the hBUB1 gene as well as mutation analysis of other mitotic checkpoint genes in lung cancers.

Adenocarcinoma↗

PubMed2000

Mutation analysis of the gene encoding the human mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) in human cell lines resistant to growth inhibition by transforming growth factor beta(1) (TGF-beta(1)).

The mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) is involved in activating the transforming growth factor beta(1) (TGF-beta(1)), an inhibitor of the cell proliferation, and limiting the insulin-like growth factor 2 mediated-growth stimulation. The M6P/IGF2R gene has been reported to be mutated and deleted in various cancers, and is a candidate tumor suppressor gene. We studied the genomic structure of the M6P/IGF2R gene and designed the intron primers to detect mutations in the M6P/IGF2R gene of genomic DNA samples. The M6P/IGF2R gene consists of 48 exons. The previously reported 23 mutations of the M6P/IGF2R gene in human cancers, liver, breast, and gastrointestinal tumors, are located in five exons, exon 27, 28, 31, 40, 48. Using the intron primers designed in this study, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis, and direct sequencing, we performed an initial analysis of the complete coding sequences of the M6P/IGF2R gene in 21 human cell lines resistant to growth inhibition by TGF-beta(1). An adenine-to-guanine transition, resulting in an asparagine-to-serine amino acid substitution, was found in one lung adenocarcinoma cell line at exon 40 where the mutation has been previously reported in human cancers. This is the first report of a mutation of the M6P/IGF2R gene in lung tumor. These results indicated that the mutation in M6P/IGF2R may be involved in human lung cancinogenesis.

Cell Line↗

PubMed2000

Clinicopathologic analysis of stage II-III hepatocellular carcinoma showing early massive recurrence after liver resection.

BACKGROUND AND AIMS: Prognosis after hepatectomy for hepatocellular carcinoma (HCC) has been improved by progress in the evaluation of hepatic functional reserve, surgical techniques and perioperative management. However, even when curative resection is performed at a relatively early stage, a considerable number of patients develop early intrahepatic and/or extrahepatic recurrence postoperatively. This study analyzed the clinicopathologic features of HCC with early recurrence. METHODS: We reviewed records of 513 consecutive patients who had undergone liver resection for HCC. There were 48 deaths within a year after surgery from recurrence, including 21 patients with stage II or III HCC (group I). Clinicopathologic parameters of group I patients were compared with those of 188 patients (group II) who developed recurrence following resection of stage II or III HCC and died more than 1 year after surgery. RESULTS: On univariate analysis, age, tumor diameter (phi), alpha-fetoprotein (AFP):phi and protein induced by vitamin K absence or antagonist II (PIVKA-II):phi were significantly greater in group I than in group II. Macroscopic portal vein invasion, microscopic vascular invasion, intrahepatic metastasis, poor differentiation, pleomorphism, sarcomatous change, vascular lake, and angiographic condensed pooling were more frequently observed in group I than group II. Five independent determinants were selected by multivariate analysis: AFP:phi, histologic pleomorphism, sarcomatous change, vascular lake and angiographic condensed pooling. CONCLUSIONS: Highly malignant HCC with extremely poor prognosis exhibits peculiar clinicopathologic characteristics, particularly histologic immaturity, and can be predicted by preoperative indicators such as markedly elevated tumor marker concentrations and condensed pooling on angiography.

Aged↗

PubMed2000

Inhibition by an angiogenesis inhibitor, TNP-470, of the growth of a human hepatoblastoma heterotransplanted into nude mice.

BACKGROUND/PURPOSE: The effect of TNP-470, an angiogenesis inhibitor, on the growth of a hepatoblastoma transplanted into nude mice was examined. METHODS: A hepatoblastoma obtained from a 3-year-old girl was serially transplanted into nude mice subcutaneously, and the transplant tumors of the seventh and eighth generations were used for experiments. Expression of various markers in the tumors was examined immunohistochemically. TNP-470 was injected subcutaneously every other day into tumor-bearing mice from 3 weeks after tumor transplantation. The proliferation of tumor cells and endothelial cells was estimated by means of the bromodeoxyuridine labeling index. RESULTS: The original hepatoblastoma showed the histology of the epithelial type, consisting of both the fetal and embryonal subtypes and was positively stained with anti-alpha-fetoprotein (AFP), anti-cytokeratin-19 and polyclonal anticarcinoembryonic antigen antibodies, and an antihuman hepatocyte antibody (hepatocyte paraffin 1). The transplant tumors consisted of solid nests of tumor cells with numerous vascular lakes of various sizes, and showed positive staining with all antibodies that reacted positively with the original hepatoblastoma. Injections of TNP-470 at the doses of 15 mg and 30 mg/kg body weight suppressed the tumor growth and the increase in the serum level of AFP dose dependently. Injections of TNP-470 also suppressed the proliferation of tumor cells and endothelial cells in the tumors. CONCLUSIONS: Hepatoblastomas maintained in nude mice retained the immunohistochemical characteristics of the original hepatoblastoma, and TNP-470 suppressed the growth of hepatoblastomas transplanted into nude mice. TNP-470 may be worth investigating further as to its usefulness as a therapy for hepatoblastomas.

Angiogenesis Inhibitors↗

PubMed2000

What patients can survive disease free after complete resection for hepatocellular carcinoma?: A multivariate analysis.

BACKGROUND: Although there have been extensive studies to determine risk factors affecting survival after resection for hepatocellular carcinoma (HCC), we still do not know which patients can survive disease free after curative resection. This study was undertaken to determine independent risk factors affecting the length of disease-free survival. METHODS: 171 patients, who survived disease free more than 1 year after curative resection, were divided into four groups according to the disease-free period: Group I (n = 96) for the patients with intrahepatic recurrence between 1 and 3 postoperative years, Group II(n = 27) for those between 3 and 5 years, Group III (n = 40) for those between 5 and 10 years and Group IV (n = 8) for those without recurrence within 10 years. The 37 variables (host factors, tumor factors, non-tumor liver factors, surgical factors) were compared among the four groups. Activity of hepatitis and hepatic fibrosis was scored by the Histological Activity Index (HAI). In a multivariate study, possible prognostic variables with a statistical difference in the disease-free survival rate among each category were preliminarily selected from the 37 variables and the independent variables were finally selected using a proportional hazard analysis. RESULTS: The patients' age, indocyanine green retention rate, microscopic tumor capsular invasion and portal invasion, cell differentiation, extent of hepatectomy, aggressiveness of chronic hepatitis and inflammatory activity assessed by HAI score were significantly different among the four groups. In the multivariate analysis, the following variables were selected as the independent determinants favorable for achieving a longer disease-free period: younger age, lower indocyanine green retention rate, solitary HCC with expansive growth, no microscopic portal invasion and lower activity of co-existing hepatitis. CONCLUSIONS: The importance of inflammatory activity in addition to aging, hepatic reserve and tumor characteristics was confirmed as a risk factor for recurrence by multivariate analysis. To achieve better disease-free survival, not only early detection but also suppression of co-existing hepatitis is necessary.

Aged↗

PubMed2000

Novel toluene elimination system in a toluene-tolerant microorganism.

In studies of Pseudomonas putida IH-2000, a toluene-tolerant microorganism, membrane vesicles (MVs) were found to be released from the outer membrane when toluene was added to the culture. These MVs were found to be composed of phospholipids, lipopolysaccharides (LPS), and very low amounts of outer membrane proteins. The MVs also contained a higher concentration of toluene molecules (0.172 +/- 0. 012 mol/mol of lipid) than that found in the cell membrane. In contrast to the wild-type strain, the toluene-sensitive mutant strain 32, which differs from the parent strain in LPS and outer membrane proteins, did not release MVs from the outer membrane. The toluene molecules adhering to the outer membrane are eliminated by the shedding of MVs, and this system appears to serve as an important part of the toluene tolerance system of IH-2000.

Bacterial Outer Membrane Proteins↗

PubMed2000

[Microscopic polyangiitis accompanying interstitial pneumonia with aluminum lung].

A 67-year-old man who had worked as an aluminum grinder had been given a diagnosis of pneumoconiosis. Ten years later, he was admitted with fever, dyspnea on exertion, and numbness. Chest roentgenograms showed linear-reticular shadows in both lower lung fields. ELISA-based tests were positive for perinuclear anti-neutrophil cytoplasmic antibody (P-ANCA). Renal biopsy specimens disclosed crescentic glomerulonephritis and angiitis of small arteries. Our diagnosis was microscopic polyangiitis accompanying interstitial pneumonia with aluminum lung. The results of high-energy dispersion X-ray microanalysis indicated that the patient's lungs contained aluminum. His general condition improved with the administration of corticosteroid and immunosuppressive agents, and his chief symptoms disappeared.

Aged↗

PubMed2000

[Mechanism of resistance to growth inhibition by transforming growth factor-beta 1 (TGF-beta 1) in primary lung cancer and new molecular targets in therapy].

Transforming Growth Factor-beta 1 (TGF-beta 1) regulates the proliferation of normal epithelial cells, and resistance to TGF-beta 1 growth inhibition is a common feature of human cancers including lung cancer. In order to understand the mechanism of resistance to growth inhibition by TGF-beta 1 and to reverse the regulation of proliferation in lung cancer, we determined the genomic structure of the genes involved in the signal transduction pathway of TGF-beta 1 and performed an initial mutation survey of the complete coding region of the genes in lung cancer and cell lines with the resistance to growth inhibition by TGF-beta 1. First, a mutation analysis of the TGF-beta type II receptor (TGF-beta RII) was performed. Point mutations of the gene were detected in several colon cancers and an adenocarcinoma of the lung in the poly-A sequence. No mutations of Smad 2, 3, 4, 5 and TGF-beta type I receptor (TGF-beta IR) genes were detected in a series of the tumors we tested, although several mutations of Smad 2 and 4 were previously reported. Frequent alterations of the p15 gene and reduced expression of p21 we already reported from our previous studies. We also determined the genomic structure of the mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R), which is involved in activating TGF-beta 1, and performed an initial mutation survey of the complete coding sequences of the gene. A point mutation at exon 40 was found in one lung adenocarcinoma cell line. In summary, alterations in the many genes involved in the signal transduction of TGF-beta 1 were found and may mediate the loss of TGF-beta 1 responsiveness in lung cancer. The molecular targets for the regulation of the proliferation of lung cancer are thought to be p15, p21 and the transcriptional regulators.

Cell Division↗

PubMed1999

Naturally occurring somatic motoneuron death in a teleost angelfish, Pterophyllum scalare.

Naturally occurring somatic motoneuron death in a teleost angelfish, Pterophyllum scalare, was investigated histochemically and electron microscopically. The number of motor axons in the ventral root, which corresponds to the motoneuron number in spinal hemisegment, was rapidly increased beyond the adult value within 3 days after hatching, and then decreased to reach the adult value within a few weeks. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) histochemistry, which detects fragmented nuclear DNA characteristic to apoptotic cells, showed that the apoptotic cells are located in the motor column of the cord in the larvae at specific developmental stages. Electron microscopic observations of the spinal cells further confirmed the motoneuron apoptosis. The present data suggest that the massive death of somatic motoneurons at certain ontogenic stages which has been known to occur in higher vertebrates also takes place in fish.

Animals↗