1
|
Hayashi T, Makino K, Ohnishi M, Kurokawa K, Ishii K, Yokoyama K, Han CG, Ohtsubo E, Nakayama K, Murata T, Tanaka M, Tobe T, Iida T, Takami H, Honda T, Sasakawa C, Ogasawara N, Yasunaga T, Kuhara S, Shiba T, Hattori M, Shinagawa H. Complete genome sequence of enterohemorrhagic Escherichia coli O157:H7 and genomic comparison with a laboratory strain K-12. DNA Res 2001; 8:11-22. [PMID: 11258796 DOI: 10.1093/dnares/8.1.11] [Citation(s) in RCA: 945] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/12/2022] Open
Abstract
Escherichia coli O157:H7 is a major food-borne infectious pathogen that causes diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome. Here we report the complete chromosome sequence of an O157:H7 strain isolated from the Sakai outbreak, and the results of genomic comparison with a benign laboratory strain, K-12 MG1655. The chromosome is 5.5 Mb in size, 859 Kb larger than that of K-12. We identified a 4.1-Mb sequence highly conserved between the two strains, which may represent the fundamental backbone of the E. coli chromosome. The remaining 1.4-Mb sequence comprises of O157:H7-specific sequences, most of which are horizontally transferred foreign DNAs. The predominant roles of bacteriophages in the emergence of O157:H7 is evident by the presence of 24 prophages and prophage-like elements that occupy more than half of the O157:H7-specific sequences. The O157:H7 chromosome encodes 1632 proteins and 20 tRNAs that are not present in K-12. Among these, at least 131 proteins are assumed to have virulence-related functions. Genome-wide codon usage analysis suggested that the O157:H7-specific tRNAs are involved in the efficient expression of the strain-specific genes. A complete set of the genes specific to O157:H7 presented here sheds new insight into the pathogenicity and the physiology of O157:H7, and will open a way to fully understand the molecular mechanisms underlying the O157:H7 infection.
Collapse
|
Comparative Study |
24 |
945 |
2
|
Yannuzzi LA, Negrão S, Iida T, Carvalho C, Rodriguez-Coleman H, Slakter J, Freund KB, Sorenson J, Orlock D, Borodoker N. Retinal angiomatous proliferation in age-related macular degeneration. Retina 2002; 21:416-34. [PMID: 11642370 DOI: 10.1097/00006982-200110000-00003] [Citation(s) in RCA: 513] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND It is known that choroidal neovascularization (CNV) in age-related macular degeneration (ARMD) may erode through the retinal pigment epithelium, infiltrate the neurosensory retina, and communicate with the retinal circulation in what has been referred to as a retinal-choroidal anastomosis (RCA). This is extremely common in the end stage of disciform disease. In recent years, the reverse also seems to be possible, as angiomatous proliferation originates from the retina and extends posteriorly into the subretinal space, eventually communicating in some cases with choroidal new vessels. This form of neovascular ARMD, termed retinal angiomatous proliferation (RAP) in this article, can be confused with CNV. PURPOSE The purpose of this article is 1) to review the clinical and angiographic characteristics of a series of patients with RAP and 2) to propose a theoretical sequence of events that accounts for the neovascularized process. METHODS In this retrospective clinical and angiographic analysis, 143 eyes with RAP (108 patients) were reviewed and classified based on their vasogenic nature and course. Clinical biomicroscopic examination, fluorescein angiography, and indocyanine green angiography were used to evaluate patients. RESULTS The results of this series suggest that angiomatous proliferation within the retina is the first manifestation of the vasogenic process in this form of neovascular ARMD. Dilated retinal vessels and pre-, intra-, and subretinal hemorrhages and exudate evolve, surrounding the angiomatous proliferation as the process extends into the deep retina and subretinal space. One or more dilated compensatory retinal vessels perfuse and drain the neovascularization, sometimes forming a retinal-retinal anastomosis. Fluorescein angiography in these patients usually revealed indistinct staining simulating occult CNV. Indocyanine green angiography was useful to make an accurate diagnosis in most cases. It revealed a focal area of intense hyperfluorescence corresponding to the neovascularization ("hot spot") and other characteristic findings. Based on understanding of the nature and progression of the neovascularized process, patients with RAP were classified into three vasogenic stages. Stage I involved proliferation of intraretinal capillaries originating from the deep retinal complex (intraretinal neovascularization [IRN]). Stage II was determined by growth of the retinal vessels into the subretinal space (subretinal neovascularization [SRN]). Stage III occurred when CNV could clearly be determined clinically or angiographically. A vascularized pigment epithelial detachment and RCA were inconsistent features of this stage. CONCLUSIONS Retinal angiomatous proliferation appears to be a distinct subgroup of neovascular ARMD. It may present in one of three vasogenic stages: IRN, SRN, or CNV. Whereas ICG angiography is helpful in diagnosing RAP and in documenting the stage of the neovascularized process, it is frequently difficult to determine the precise nature and location of the new vessel formation. It is important for clinicians to recognize the vasogenic potential and the associated manifestations of this peculiar form of neovascular ARMD so that a proper diagnosis can be made, and when possible, an appropriate management administered.
Collapse
|
|
23 |
513 |
3
|
Urata Y, Honma S, Goto S, Todoroki S, Iida T, Cho S, Honma K, Kondo T. Melatonin induces gamma-glutamylcysteine synthetase mediated by activator protein-1 in human vascular endothelial cells. Free Radic Biol Med 1999; 27:838-47. [PMID: 10515588 DOI: 10.1016/s0891-5849(99)00131-8] [Citation(s) in RCA: 258] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Academic Contribution Register] [Indexed: 12/14/2022]
Abstract
In the present study, we show that melatonin induces the expression of gamma-glutamylcysteine synthetase (gamma-GCS), the rate-limiting enzyme of glutathione (GSH) synthesis, in ECV304 human vascular endothelial cells. One micromolar melatonin induced the expression of gamma-GCS mRNA followed by an increase in the concentration of GSH with a peak at 24 h. An electrophoretic mobility shift assay showed that melatonin stimulates the DNA-binding activity of activator protein-1 (AP-1) as well as retinoid Z receptor/retinoid receptor-related orphan receptor alpha (RZR/RORalpha). ECV304 cells transiently transfected with a plasmid containing the gamma-GCS promoter-luciferase construct showed increased luciferase activity when treated with melatonin. The melatonin-dependent luciferase activity was found in the gamma-GCS promoter containing AP-1 site. The luciferase activity mediated by AP-1 was repressed in the promoter containing RZR/RORalpha site. In addition, cell cycle analysis showed that melatonin increases the number of cells in the G0/G1 phase; however, treatment of the cells with buthionine sulfoximine, a specific inhibitor of gamma-GCS, abolished the effect of melatonin on the cell cycle, suggesting induction of cell arrest by melatonin requires GSH. As conclusion, induction of GSH synthesis by melatonin protects cells against oxidative stress and regulates cell proliferation.
Collapse
MESH Headings
- Buthionine Sulfoximine/pharmacology
- Cell Cycle/drug effects
- Cell Line
- DNA-Binding Proteins/analysis
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation, Enzymologic/drug effects
- Genes, Reporter
- Glutamate-Cysteine Ligase/genetics
- Glutamate-Cysteine Ligase/metabolism
- Glutathione/biosynthesis
- Glutathione/metabolism
- Humans
- Melatonin/pharmacology
- Nuclear Receptor Subfamily 1, Group F, Member 1
- Oxidative Stress/drug effects
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Receptors, Cell Surface
- Receptors, Cytoplasmic and Nuclear
- Receptors, Melatonin
- Receptors, Retinoic Acid
- Trans-Activators
- Transcription Factor AP-1/metabolism
- Transfection
- tert-Butylhydroperoxide/pharmacology
Collapse
|
|
26 |
258 |
4
|
Honda T, Iida T. The pathogenicity of Vibrio parahaemolyticus and the role of the thermostable direct haemolysin and related haemolysins. ACTA ACUST UNITED AC 1993. [DOI: 10.1097/00013542-199304000-00006] [Citation(s) in RCA: 257] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/25/2022]
|
|
32 |
257 |
5
|
Sivaraman A, Leach JK, Townsend S, Iida T, Hogan BJ, Stolz DB, Fry R, Samson LD, Tannenbaum SR, Griffith LG. A microscale in vitro physiological model of the liver: predictive screens for drug metabolism and enzyme induction. Curr Drug Metab 2006; 6:569-91. [PMID: 16379670 DOI: 10.2174/138920005774832632] [Citation(s) in RCA: 231] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/22/2022]
Abstract
In vitro models of the liver using isolated primary hepatocytes have been used as screens for measuring the metabolism, toxicity and efficacy of xenobiotics, for studying hepatocyte proliferation, and as bioartificial liver support systems. Yet, primary isolated hepatocytes rapidly lose liver specific functions when maintained under standard in vitro cell culture conditions. Many modifications to conventional culture methods have been developed to foster retention of hepatocyte function. Still, not all of the important functions -- especially the biotransformation functions of the liver -- can as yet be replicated at desired levels, prompting continued development of new culture systems. In the first part of this article, we review primary hepatocyte in vitro systems used in metabolism and enzyme induction studies. We then describe a scalable microreactor system that fosters development of 3D-perfused micro-tissue units and show that primary rat cells cultured in this system are substantially closer to native liver compared to cells cultured by other in vitro methods, as assessed by a broad spectrum of gene expression, protein expression and biochemical activity metrics. These results provide a foundation for extension of this culture model to other applications in drug discovery -- as a model to study drug-drug interactions, as a model for the assessment of acute and chronic liver toxicity arising from exposure to drugs or environmental agents; and as a disease model for the study of viral hepatitis infection and cancer metastasis.
Collapse
|
Research Support, U.S. Gov't, Non-P.H.S. |
19 |
231 |
6
|
Kim T, Shijo H, Kokawa H, Tokumitsu H, Kubara K, Ota K, Akiyoshi N, Iida T, Yokoyama M, Okumura M. Risk factors for hemorrhage from gastric fundal varices. Hepatology 1997. [PMID: 9021939 DOI: 10.1002/hep.510250209] [Citation(s) in RCA: 210] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Academic Contribution Register] [Indexed: 12/12/2022]
Abstract
The incidence and the risk factors of hemorrhage from gastric fundal varices (FV) have not been fully evaluated. We therefore conducted a retrospective and prospective study to define the incidence and risk factors for such episodes. We investigated 132 patients with cirrhosis and gastric FV. Of these 132 patients, 15 patients had hemorrhagic FV at the time of enrollment. The clinical characteristics were compared between these patients and those without a first hemorrhage from FV. In the patients who had never previously bled, the incidence and risk factors were prospectively investigated. The size of FV was greater and red-spot on the FV were more prevalent in patients with hemorrhagic FV. Child's status was also more severe in these patients. In the 117 patients who had never bled, 34 hemorrhages from FV occurred during the follow-up period. The cumulative risk for such hemorrhage at 1, 3, and 5 years was 16%, 36%, and 44%, respectively. A multiple regression analysis (Cox's model) revealed the size of varices, red-spot on the FV, and Child's status to be statistically significant, as well as independent predictors for hemorrhage from FV. The endoscopic criteria (size of the largest varix and presence of red-spot), as well as the hepatic functional reserve, provide the most essential information for predicting a hemorrhage from FV. An estimation of the probability for hemorrhage from FV based on Cox's model may therefore be beneficial in the clinical management of patients with high-risk FV.
Collapse
|
|
28 |
210 |
7
|
Iida T, Kishi S, Hagimura N, Shimizu K. Persistent and bilateral choroidal vascular abnormalities in central serous chorioretinopathy. Retina 1999; 19:508-12. [PMID: 10606450 DOI: 10.1097/00006982-199911000-00005] [Citation(s) in RCA: 175] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND To clarify the role of choroidal vascular abnormalities in central serous chorioretinopathy (CSC) in active stage, remission, and recurrence. METHODS Indocyanine green angiography and fluorescein angiography were performed in 105 eyes (104 patients) with active CSC. Forty-six patients were followed up for 6 to 48 months (mean +/- standard deviation, 22.5 +/- 8.9 months) with repeated angiography (mean +/- standard deviation, 3.5 +/- 1.5 times). Indocyanine green angiography and fluorescein angiography also were performed during remission in all 46 eyes with CSC and during recurrent CSC in 6 eyes. Unaffected fellow eyes underwent angiographic examinations in all patients. RESULTS In active CSC, indocyanine green angiography showed a choroidal filling delay (71%), venous dilation (61%), and focal choroidal hyperfluorescence (96%) surrounding leakage from the retinal pigment epithelium. Focal choroidal hyperfluorescence was present in unaffected areas of affected eyes (55%). The choroidal venous dilation (36%) and choroidal hyperfluorescence (62%) were noted even in unaffected fellow eyes. These choroidal abnormalities persisted during remission after leakage ceased throughout the follow-up period. In the six patients with recurrent CSC, new leakage developed in the areas of persistent choroidal hyperfluorescence. Central serous chorioretinopathy developed in the unaffected fellow eye in one of these six patients. CONCLUSION Choroidal vascular abnormalities persist in both eyes even after leakage from the retinal pigment epithelium ceases. Central serous chorioretinopathy may recur in areas of choroidal vascular abnormalities.
Collapse
|
Comparative Study |
26 |
175 |
8
|
Nasu H, Iida T, Sugahara T, Yamaichi Y, Park KS, Yokoyama K, Makino K, Shinagawa H, Honda T. A filamentous phage associated with recent pandemic Vibrio parahaemolyticus O3:K6 strains. J Clin Microbiol 2000; 38:2156-61. [PMID: 10834969 PMCID: PMC86752 DOI: 10.1128/jcm.38.6.2156-2161.2000] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/20/2022] Open
Abstract
A specific serotype, O3:K6, of Vibrio parahaemolyticus has recently been causing epidemics of gastroenteritis in Southeast Asia, Japan, and North America. To examine whether the new O3:K6 strains possess characteristics that may exacerbate outbreaks, we compared V. parahaemolyticus O3:K6 strains with non-O3:K6 strains using strains isolated from individuals with traveler's diarrhea at Kansai Airport Quarantine Station, Osaka, Japan. All 24 O3:K6 strains possessed a common plasmid, pO3K6 (DNA size, 8,782 bp, with 10 open reading frames [ORFs]). The gene organization of pO3K6 was similar to that of Vf33, a filamentous phage previously described in V. parahaemolyticus. We isolated a phage (phage f237) from the culture supernatant of V. parahaemolyticus O3:K6 strain KXV237, which formed a turbid plaque on an indicator strain. The genome of f237 was single-stranded DNA, and the double-stranded DNA obtained by treatment of the genome with DNA polymerase was identical to that of pO3K6 when analyzed by agarose gel electrophoresis after HindIII digestion. Furthermore, the N-terminal amino acid sequence of the f237 major coat protein was found in ORF4 of pO3K6. Our results showed that pO3K6 is a replicative form of f237. Among the ORFs found in the f237 genome, the sequence of ORF8 had no significant homology to those of any proteins in databases. ORF8 was located on a region corresponding to the distinctive region of Vf33, and its G+C content was apparently lower than that of the remaining DNA sequence of f237. By colony hybridization, ORF8 was detected only in O3:K6 strains isolated since 1996 and was not found in O3:K6 strains isolated before 1996 and clinical V. parahaemolyticus strains other than those of serotype O3:K6. Thus, this study shows that f237 is exclusively associated with recent V. parahaemolyticus O3:K6 strains. The ORF8 gene can be a useful genetic marker for the identification of the recently widespread O3:K6 strains of V. parahaemolyticus.
Collapse
|
research-article |
25 |
163 |
9
|
Goto S, Iida T, Cho S, Oka M, Kohno S, Kondo T. Overexpression of glutathione S-transferase pi enhances the adduct formation of cisplatin with glutathione in human cancer cells. Free Radic Res 1999; 31:549-58. [PMID: 10630679 DOI: 10.1080/10715769900301121] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 10/24/2022]
Abstract
In this paper, we provide direct evidence that glutathione S-transferase pi (GSTpi) detoxifies cisplatin (CDDP). We used human colonic cancer HCT8 cells sensitive and resistant to CDDP, the level of cisplatin-glutathione adduct (DDP-GSH) being higher in the resistant cells. There was an overexpression of GSTpi mRNA in these CDDP-resistant cells. Incubation of the cells with CDDP resulted in the formation of DDP-GSH dependent on the CDDP concentration and the incubation time. The formation of DDP-GSH was abolished when the cells were pre-treated with ethacrynic acid or ketoprofen, inhibitors of GSTpi. Purified GSTpi also catalyzed the formation of DDP-GSH in vitro, with an apparent Km of 0.23 mM for CDDP and an apparent Vmax of 4.9 nmol/min/mg protein. The increase in DDP-GSH produced by GSTpi was linear with incubation time up to 3 h and optimal of pH 7.4. A GSTpi transfectant cell line was constructed in HCT8 cells using a pcDNA3.1 (-)/Myc-His B with an expression vector containing cDNA for GSTpi. Transfection of GSTpi cDNA into HCT8 cells resulted in an increase in the expression of GSTpi by 1.4-fold in parallel with an augmentation of the formation of DDP-GSH. These results suggest that GSTpi plays a role in the formation of DDP-GSH and the acquisition of resistance to CDDP in cancer cells.
Collapse
|
|
26 |
147 |
10
|
Makino K, Ishii K, Yasunaga T, Hattori M, Yokoyama K, Yutsudo CH, Kubota Y, Yamaichi Y, Iida T, Yamamoto K, Honda T, Han CG, Ohtsubo E, Kasamatsu M, Hayashi T, Kuhara S, Shinagawa H. Complete nucleotide sequences of 93-kb and 3.3-kb plasmids of an enterohemorrhagic Escherichia coli O157:H7 derived from Sakai outbreak. DNA Res 1998; 5:1-9. [PMID: 9628576 DOI: 10.1093/dnares/5.1.1] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/12/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) O157:H7, derived from an outbreak in Sakai city, Japan in 1996, possesses two kinds of plasmids: a 93-kb plasmid termed pO157, found in clinical EHEC isolates world-wide and a 3.3-kb plasmid termed pOSAK1, prevalent in EHEC strains isolated in Japan. Complete nucleotide sequences of both plasmids have been determined, and the putative functions of the encoded proteins and the cis-acting DNA sequences have been analyzed. pO157 shares strikingly similar genes and DNA sequences with F-factor and the transmissible drug-resistant plasmid R100 for DNA replication, copy number control, plasmid segregation, conjugative functions and stable maintenance in the host, although it is defective in DNA transfer by conjugation due to the truncation and deletion of the required genes and DNA sequences. In addition, it encodes several proteins implicated in EHEC pathogenicity such as an EHEC hemolysin (HlyA), a catalase-peroxidase (KatP), a serine protease (EspP) and type II secretion system. pOSAK1 possesses a ColE1-like replication system, and the DNA sequence is extremely similar to that of a drug-resistant plasmid, NTP16, derived from Salmonella typhimurium except that it lacks drug resistance transposons.
Collapse
|
|
27 |
138 |
11
|
Iida T, Moriyama T, Kobata K, Morita A, Murayama N, Hashizume S, Fushiki T, Yazawa S, Watanabe T, Tominaga M. TRPV1 activation and induction of nociceptive response by a non-pungent capsaicin-like compound, capsiate. Neuropharmacology 2003; 44:958-67. [PMID: 12726827 DOI: 10.1016/s0028-3908(03)00100-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 10/27/2022]
Abstract
Capsiate is a capsaicin-like ingredient of a non-pungent cultivar of red pepper, CH-19 sweet. To elucidate the mechanisms underlying the non-pungency of capsiate, we investigated whether capsiate activates the cloned capsaicin receptor, TRPV1 (VR1). In patch-clamp experiments, capsiate was found to activate TRPV1 expressed transiently in HEK293 cells with a similar potency as capsaicin. Capsiate induced nociceptive responses in mice when injected subcutaneously into their hindpaws with a similar dose dependency as capsaicin. These data indicate that the non-pungent capsiate is an agonist for TRPV1 and could excite peripheral nociceptors. In contrast to this, capsiate did not induce any significant responses when applied to the skin surface, eye or oral cavity of mice, suggesting that capsiate requires direct access to nerve endings to exhibit its effects. Capsiate was proved to have high lipophilicity and to be easily broken down in normal aqueous conditions, leading to less accessibility to nociceptors. Another highly lipophilic capsaicin analogue, olvanil, was similar to capsiate in that it did not produce irritant responses when applied to the skin surface, although it could activate TRPV1. Taken together, high lipophilicity and instability might be critical determinants for pungency and so help in understanding the effects of capsaicin-related compounds.
Collapse
|
|
22 |
133 |
12
|
Stojilković SS, Merelli F, Iida T, Krsmanović LZ, Catt KJ. Endothelin stimulation of cytosolic calcium and gonadotropin secretion in anterior pituitary cells. Science 1990; 248:1663-6. [PMID: 2163546 DOI: 10.1126/science.2163546] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 12/30/2022]
Abstract
The presence of endothelin, a vasoconstrictor peptide, in the hypothalamus and posterior pituitary suggests that it also regulates neural and other nonvascular target cells. In pituitary gonadotrophs, low doses of endothelin evoked oscillations in the intracellular calcium concentration, and high doses induced a biphasic calcium response. Mobilization of intracellular calcium predominated during the spike phase of the calcium response to endothelin, whereas calcium entry through dihydropyridine-sensitive channels contributed to both the spike and plateau phases of the calcium response. Endothelin was a potent as hypothalamic gonadotropin-releasing hormone (GnRH) in stimulation of gonadotropin release in perifused pituitary cells. Endothelin bound specifically to pituitary cells with a dissociation constant of 70 picomolar, and induced rapid formation of inositol trisphosphate and diacyglycerol. Although intracellular calcium concentration and gonadotropin secretory responses to endothelin were independent to the GnRH receptor, endothelin and GnRH appeared to have a common signal transduction mechanism. These observations suggest that endothelin can act as a neuropeptide to regulate anterior pituitary function.
Collapse
|
|
35 |
129 |
13
|
Kuboniwa M, Amano A, Kimura KR, Sekine S, Kato S, Yamamoto Y, Okahashi N, Iida T, Shizukuishi S. Quantitative detection of periodontal pathogens using real-time polymerase chain reaction with TaqMan probes. ACTA ACUST UNITED AC 2004; 19:168-76. [PMID: 15107068 DOI: 10.1111/j.0902-0055.2004.00135.x] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 10/26/2022]
Abstract
Quantitative analysis, with identification of periodontopathic bacteria, is important for the diagnosis, therapeutic evaluation and risk assessment of periodontal disease. We developed a highly sensitive and specific method using real-time polymerase chain reaction (PCR) to detect and quantify six periodontal bacteria: Porphyromonas gingivalis, Tannerella forsythia, Actinobacillus actinomycetemcomitans, Treponema denticola, Prevotella intermedia, and Prevotella nigrescens. Species-specific TaqMan probe/primer sets were designed according to 16S ribosomal RNA gene sequences. Plaque and tongue debris specimens were collected from 10 patients with advanced periodontitis and 10 periodontal healthy individuals and analyzed. All species, except for P. nigrescens, were detected in samples from diseased sites in significantly greater numbers than in those from healthy sites, whereas greater numbers of P. nigrescens were found in the controls. These results suggest that the present real-time PCR method with the designed probe/primer sets enabled sensitive detection of the six periodontal bacteria, and may also assist future microbial studies of periodontal diseases.
Collapse
|
Journal Article |
21 |
129 |
14
|
Shinkai H, Ito T, Iida T, Kitao Y, Yamada H, Uchida I. 4-Aminoquinolines: novel nociceptin antagonists with analgesic activity. J Med Chem 2000; 43:4667-77. [PMID: 11101358 DOI: 10.1021/jm0002073] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/29/2022]
Abstract
Small-molecule nociceptin antagonists were synthesized to examine their therapeutic potential. After a 4-aminoquinoline derivative was found to bind with the human ORL(1) receptor, a series of 4-aminoquinolines and related compounds were synthesized and their binding was evaluated. Elucidation of structure-activity relationships eventually led to the optimum compounds. One of these compounds, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide hydrochloride (11) not only antagonized nociceptin-induced allodynia in mice but also showed analgesic effect in a hot plate test using mice and in a formalin test using rats. Its analgesic effect was not antagonized by the opioid antagonist naloxone. These results indicate that this nociceptin antagonist has the potential to become a novel type of analgesic that differs from mu-opioid agonists.
Collapse
|
|
25 |
128 |
15
|
Iida T, Hagimura N, Sato T, Kishi S. Evaluation of central serous chorioretinopathy with optical coherence tomography. Am J Ophthalmol 2000; 129:16-20. [PMID: 10653407 DOI: 10.1016/s0002-9394(99)00272-x] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To evaluate central serous chorioretinopathy with optical coherence tomography during the acute phase and after resolution of the acute phase. METHODS In a prospective study, 23 consecutive eyes of 23 patients (19 men, four women; mean age +/- SD, 46.0+/-8.1 years; range, 29 to 60 years) with central serous chorioretinopathy were examined with optical coherence tomography during the acute phase and after resolution of the retinal detachment. After the initial examination, the patients were reexamined for 3 to 6 months (mean, 4.7+/-1.1 months). Cross-sectional retinal images through the center of the fovea were obtained from all eyes by optical coherence tomography. The retinal thickness at the center of the fovea was measured. The difference between the retinal thickness during the acute phase and after resolution of the retinal detachment was statistically analyzed using the Wilcoxon test. We also examined a grayish-white lesion that corresponded to the leakage point in fluorescein angiography in four eyes. RESULTS In the acute phase, neurosensory retina was thickened within the area of serous retinal detachment in all 23 eyes. The detached retina was thicker than the reattached retina after resolution of the retinal detachment in all eyes. The retinal thickness at the center of the fovea during the acute phase (range, 157 to 236 microm; mean +/- SD, 196.9+/-22.6 microm) was significantly thickened compared with that after resolution (range, 105 to 152 microm; mean +/- SD, 124.8+/-10.7 microm; P<.0001, Wilcoxon test). In the acute phase, areas of low reflectivity localized within the detached retina were observed in 18 of the 23 eyes. In the area of the grayish-white lesion, optical coherence tomography showed a moderately reflective mass bridging the detached neurosensory retina and retinal pigment epithelium in the four eyes; the outer layer of the detached retina was more highly reflective in these eyes. The retinal pigment epithelium was focally detached beneath the subretinal reflective mass in three of the four eyes. CONCLUSIONS In all eyes studied, neurosensory retina was thickened within the area of serous retinal detachment in the acute phase of central serous chorioretinopathy. The grayish-white lesion seems to be a fibrinous exudate that accumulates in the subretinal space and infiltrates into the outer retina.
Collapse
|
|
25 |
120 |
16
|
Iida T, Ohno H, Nakaseko C, Sakuma M, Takeda-Ezaki M, Arase H, Kominami E, Fujisawa T, Saito T. Regulation of cell surface expression of CTLA-4 by secretion of CTLA-4-containing lysosomes upon activation of CD4+ T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:5062-8. [PMID: 11046036 DOI: 10.4049/jimmunol.165.9.5062] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Academic Contribution Register] [Indexed: 11/19/2022]
Abstract
CTLA-4 is expressed on the surface of activated T cells and negatively regulates T cell activation. Because a low-level expression of CTLA-4 on the cell surface is sufficient to induce negative signals in T cells, the surface expression of CTLA-4 is strictly regulated. We previously demonstrated that the association of CTLA-4 with the clathrin-associated adaptor complex AP-2 induces internalization of CTLA-4 and keeps the surface expression low. However, the mechanism to induce high expression on the cell surface upon stimulation has not yet been clarified. To address this, we investigated the intracellular dynamics of CTLA-4 by analyzing its localization and trafficking in wild-type and mutant CTLA-4-transfected Th1 clones. CTLA-4 is accumulated in intracellular granules, which we identified as lysosomes. CTLA-4 is degraded in lysosomes in a short period, and the degradation process may serve as one of the mechanisms to regulate CTLA-4 expression. Upon TCR stimulation, CTLA-4-containing lysosomes are secreted as proven by the secretion of cathepsin D and beta-hexosaminidase in parallel with the increase of surface expression of CTLA-4 and lysosomal glycoprotein 85, a lysosomal marker. These results suggest that the cell surface expression of CTLA-4 is up-regulated upon stimulation by utilizing a mechanism of secretory lysosomes in CD4(+)T cells.
Collapse
|
|
25 |
120 |
17
|
Kobayashi E, Ando K, Nakano H, Iida T, Ohno H, Morimoto M, Tamaoki T. Calphostins (UCN-1028), novel and specific inhibitors of protein kinase C. I. Fermentation, isolation, physico-chemical properties and biological activities. J Antibiot (Tokyo) 1989; 42:1470-4. [PMID: 2478514 DOI: 10.7164/antibiotics.42.1470] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/01/2023]
Abstract
A novel complex of calphostin (UCN-1028), which specifically inhibits protein kinase C (PKC) has been isolated from the culture broth of a fungi Cladosporium cladosporioides. Purification of individual components was carried out by silica gel, non-porus resin Diaion HP-20SS and Sephadex LH-20 chromatography, leading to isolation of five closely related components. A, B, C, D and I. Calphostins showed cytotoxic activities against various tumor cells, and these cytotoxicities were proportional to their inhibitory activities against PKC.
Collapse
|
|
36 |
114 |
18
|
Fukuta S, Iida T, Mizukami Y, Ishida A, Ueda J, Kanbe M, Ishimoto Y. Detection of Japanese yam mosaic virus by RT-LAMP. Arch Virol 2003; 148:1713-20. [PMID: 14505084 DOI: 10.1007/s00705-003-0134-5] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 10/26/2022]
Abstract
Arapid and simple procedure is described to detect the genomic RNA molecule of Japanese yam mosaic potyvirus (JYMV). This method, named RT-LAMP, allows direct detection of RNA from infected plants without careful RNA extraction, rapid thermal cycling and gel electrophoresis. RT-LAMP was successfully applied to leaves, propagules and roots of Japanese yam infected with JYMV. One of the characteristics of the RT-LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of by-product, pyrophospate ion, is produced yielding a white precipitate of magnesium pyrophosphate in the reaction mixture. The presence or absence of this white precipitate allows easy detection of the amplification of JYMV genomic RNA without gel electrophoresis.
Collapse
|
|
22 |
105 |
19
|
Kiyohara H, Torigoe S, Kaida N, Asaki T, Iida T, Hayashi H, Takizawa N. Cloning and characterization of a chromosomal gene cluster, pah, that encodes the upper pathway for phenanthrene and naphthalene utilization by Pseudomonas putida OUS82. J Bacteriol 1994; 176:2439-43. [PMID: 8157614 PMCID: PMC205370 DOI: 10.1128/jb.176.8.2439-2443.1994] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/29/2023] Open
Abstract
A 25-kb DNA SalI fragment cloned from the chromosomal DNA of Pseudomonas putida OUS82, which utilizes phenanthrene (Phn+) and naphthalene (Nah+), carried all of the genes necessary for upper naphthalene catabolism. Cosmid recombinant pIP7 complemented both the Nah- and Phn- defects of OUS8211 (Trp-Nah-Phn-Sal+[salicylate utilizing]Hna+[1-hydroxy-2-naphthoate utilizing]) and only the Phn- defect of OUS8212 (Trp-Nah-Phn-Sal-Hna+). The results indicate that strain OUS82 uses different pathways after o-hydroxycarboxylic aromatics in the catabolism of naphthalene and phenanthrene.
Collapse
|
research-article |
31 |
101 |
20
|
Abstract
In this paper, the classification of halitosis and the examination procedures used in diagnosing halitosis are outlined. Halitosis is classified into categories of genuine halitosis, pseudo-halitosis and halitophobia. Genuine halitosis is subclassified into physiologic halitosis and pathologic halitosis. Pathologic halitosis itself is subdivided into oral and extraoral halitosis. Patients diagnosed with pseudo-halitosis and halitophobia usually complain about having oral malodour that does not really exist. Pseudohalitosis can be treated by dental practitioners, but halitophobic patients must be referred to psychological specialists. Oral malodour can be measured using an organoleptic measurement or a gas chromatography analysis. The organoleptic measurement is the most practical procedure with which one can evaluate oral malodour. Gas chromatography (GC) analysis using a flame photometric detector has been shown to be the gold standard for measuring oral malodour, owing its reputation to its objectivity and reproducibility. Moreover, GC is specific for volatile sulphur compounds (VSC), which are the main causes of oral malodour. It has been demonstrated that there is a high correlation between the intensity of oral malodour and the VSC concentration as measured by GC.
Collapse
|
|
23 |
99 |
21
|
Yasuzawa T, Iida T, Yoshida M, Hirayama N, Takahashi M, Shirahata K, Sano H. The structures of the novel protein kinase C inhibitors K-252a, b, c and d. J Antibiot (Tokyo) 1986; 39:1072-8. [PMID: 3759659 DOI: 10.7164/antibiotics.39.1072] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/07/2023]
Abstract
The structures of four new protein kinase C inhibitors of microbial origin, K-252a, b, c and d were determined by spectral studies and chemical conversion.
Collapse
|
|
39 |
90 |
22
|
Makino K, Yokoyama K, Kubota Y, Yutsudo CH, Kimura S, Kurokawa K, Ishii K, Hattori M, Tatsuno I, Abe H, Iida T, Yamamoto K, Onishi M, Hayashi T, Yasunaga T, Honda T, Sasakawa C, Shinagawa H. Complete nucleotide sequence of the prophage VT2-Sakai carrying the verotoxin 2 genes of the enterohemorrhagic Escherichia coli O157:H7 derived from the Sakai outbreak. Genes Genet Syst 1999; 74:227-39. [PMID: 10734605 DOI: 10.1266/ggs.74.227] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/23/2022] Open
Abstract
The enterohemorrhagic Escherichia coli (EHEC) O157:H7 strain RIMD 0509952, derived from an outbreak in Sakai city, Japan, in 1996, produces two kinds of verotoxins, VT1 and VT2, encoded by the stx1 and stx2 genes. In the EHEC strains, as well as in other VT-producing E. coli strains, the toxins are encoded by lysogenic bacteriophages. The EHEC O157:H7 strain RIMD 0509952 did not produce plaque-forming phage particles upon inducing treatments. We have determined the complete nucleotide sequence of a prophage, VT2-Sakai, carrying the stx2A and stx2B genes on the chromosome, and presumed the putative functions of the encoded proteins and the cis-acting DNA elements based on sequence homology data. To our surprise, the sequences in the regions of VT2-Sakai corresponding to the early gene regulators and replication proteins, and the DNA sequences recognized by the regulators share very limited homology to those of the VT2-encoding 933W phage carried by the EHEC O157:H7 strain EDL933 reported by Plunkett et al. (J. Bacteriol., p1767-1778, 181, 1999), although the sequences corresponding to the structural components are almost identical. These data suggest that these two phages were derived from a common ancestral phage and that either or both of them underwent multiple genetic rearrangements. An IS629 insertion was found downstream of the stx2B gene and upstream of the lysis gene S, and this might be responsible for the absence of plaque-forming activity in the lysate obtained after inducing treatments.
Collapse
|
|
26 |
85 |
23
|
Yamaichi Y, Iida T, Park KS, Yamamoto K, Honda T. Physical and genetic map of the genome of Vibrio parahaemolyticus: presence of two chromosomes in Vibrio species. Mol Microbiol 1999; 31:1513-21. [PMID: 10200969 DOI: 10.1046/j.1365-2958.1999.01296.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/20/2022]
Abstract
We constructed a physical map of the genomic DNA (5.1 Mb) for Vibrio parahaemolyticus strain AQ4673 by combining 17 adjacent NotI fragments. This map shows two circular replicons of 3.2 and 1.9 Mb. Pulsed-field gel electrophoresis (PFGE) of undigested genomic DNA revealed two bands of corresponding sizes. Analysis both by NotI digestion and by Southern blot of the two isolated bands confirmed the existence of two replicons. The presence of genes for 16S rRNA on both the replicons indicates that the replicons are chromosomes rather than megaplasmids. The two bands were also seen after PFGE of undigested genomic DNA of V. parahaemolyticus strains other than AQ4673, and of strains belonging to other Vibrio species, such as V. vulnificus, V. fluvialis and various serovars and biovars of V. cholerae. It is noteworthy that V. cholerae O1 strain 569B, a classical biovar, was also shown to have two replicons of 2.9 and 1.2 Mb, which does not agree with a physical map proposed in a previous study. Our results suggest that a two-replicon structure is common throughout Vibrio species.
Collapse
|
|
26 |
83 |
24
|
Kasa N, Iida T, Iwamoto H. Maximum power point tracking with capacitor identifier for photovoltaic power system. ACTA ACUST UNITED AC 2000. [DOI: 10.1049/ip-epa:20000641] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/20/2022]
|
|
25 |
83 |
25
|
Suthienkul O, Ishibashi M, Iida T, Nettip N, Supavej S, Eampokalap B, Makino M, Honda T. Urease production correlates with possession of the trh gene in Vibrio parahaemolyticus strains isolated in Thailand. J Infect Dis 1995; 172:1405-8. [PMID: 7594689 DOI: 10.1093/infdis/172.5.1405] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/26/2023] Open
Abstract
A total of 489 Vibrio parahaemolyticus isolates from patients in Thailand with diarrhea was examined for the presence of thermostable direct hemolysin (TDH) and TDH-related hemolysin genes (tdh and trh, respectively), their serovars, TDH production, and urease activity. Of the strains, 81% were positive only for the tdh gene, 6% for both trh and tdh genes, and 2% for the trh gene only. Thirty-seven (8%) of the 489 isolates were positive for urease production. Of special interest, all urease-positive strains possessed the trh gene, and conversely, urease-negative strains lacked the gene, indicating that urease production by V. parahaemolyticus strains strongly correlates with the possession of the trh gene. Thus, the urease-positive phenotype of V. parahaemolyticus can be considered an indication of virulent (trh-possessing) V. parahaemolyticus strains in clinical diagnosis.
Collapse
|
Comparative Study |
30 |
82 |