101
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Sohda T, Iwata K, Tsutsu N, Kamimura S, Shijo H, Sakisaka S. Increased expression of transforming growth factor-alpha in a patient with recurrent hepatocellular carcinoma following partial hepatectomy. Pathology 2001; 33:511-4. [PMID: 11827422 DOI: 10.1080/00313020152635810] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A 45-year-old woman with chronic hepatitis B underwent partial hepatectomy for hepatocellular carcinoma (HCC). However, the HCC recurred 2 months after surgery and rapid progression of the disease resulted in her death. Immunohistochemistry showed that transforming growth factor-alpha (TGFalpha) was barely expressed in the liver specimens obtained at hepatic resection, whereas autopsy specimens were strongly stained with anti-TGFalpha antibody in the cytoplasm of both non-tumourous and tumourous liver cells. A higher level of Ki67 expression, a proliferating marker, was observed in the recurrent HCC, similar to that of TGFalpha. Thus, we speculate that the partial hepatectomy increased the level of TGFalpha leading to recurrence and progression of HCC through an autocrine/paracrine mechanism.
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102
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Imbe H, Iwata K, Zhou QQ, Zou S, Dubner R, Ren K. Orofacial deep and cutaneous tissue inflammation and trigeminal neuronal activation. Implications for persistent temporomandibular pain. Cells Tissues Organs 2001; 169:238-47. [PMID: 11455119 DOI: 10.1159/000047887] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A rat model has been developed to characterize the responses of brainstem trigeminal neurons to orofacial deep and cutaneous tissue inflammation and hyperalgesia. Complete Freund's adjuvant (CFA) was injected unilaterally into the rat temporomandibular joint (TMJ) or perioral (PO) skin to produce inflammation in deep or cutaneous tissues, respectively. The TMJ and PO inflammation resulted in orofacial behavioral hyperalgesia and allodynia that peaked within 4-24 h and persisted for at least 2 weeks. Compared to cutaneous CFA injection, the injection of CFA into the TMJ produced a significantly stronger inflammation associated with a selective upregulation of preprodynorphin mRNA in the trigeminal spinal complex, an enhanced medullary dorsal horn hyperexcitability, and a greater trigeminal Fos protein expression, a marker of neuronal activation. The Fos-LI induced by TMJ inflammation persisted longer, was more intense, particularly in the superficial laminae, and more widespread rostrocaudally. Thus, the inflammatory irritant produces a stronger effect in deep than in cutaneous orofacial tissue. As there is heavy innervation of the TMJ by unmyelinated nerve endings, a strong nociceptive primary afferent barrage is expected following inflammation. An increase in TMJ C-fiber input after inflammation and strong central neuronal activation may initiate central hyperexcitability and contribute to persistent pain associated with temporomandibular disorders. Since deep inputs may be more effective in inducing central neuronal excitation than cutaneous inputs, greater sensory disturbances may occur in pain conditions involving deep tissues than in those involving cutaneous tissues.
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103
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Ogata S, Inoue K, Iwata K, Okumura K, Taguchi H. Apoptosis induced by picolinic acid-related compounds in HL-60 cells. Biosci Biotechnol Biochem 2001; 65:2337-9. [PMID: 11758936 DOI: 10.1271/bbb.65.2337] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have found that niacin-related compounds, particularly picolinic acid, induced apoptosis in human leukemia cells. In this paper, we investigated whether various picolinic acid-related compounds had apoptosis-inducing activities or not. Particularly, fusaric acid, picolinaldehyde, nicotinaldehyde, 2-aminopyridine, and 3-aminopyridine also induced apoptosis in HL-60 cells. These results suggest that pyridine substituted with various groups and the consequent change of resonance structure may have an important role in the induction of apoptosis.
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104
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Väänänen A, Srinivas R, Parikka M, Palosaari H, Bartlett JD, Iwata K, Grenman R, Stenman UH, Sorsa T, Salo T. Expression and regulation of MMP-20 in human tongue carcinoma cells. J Dent Res 2001; 80:1884-9. [PMID: 11706946 DOI: 10.1177/00220345010800100501] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Human matrix metalloproteinase-20 (MMP-20, enamelysin) fragments the enamel-specific protein amelogenin and has been shown to be synthesized exclusively by odontoblasts and ameloblasts and in certain odontogenic tumors. Here we demonstrate, for the first time, the expression of MMP-20 mRNA and protein in two carcinoma cell lines originating from the tongue. Treatment of the SCC-25 and HSC-3 cells with phorbol 12-myristate 13-acetate (10 nmol/L) up-regulated MMP-20 mRNA and protein expression by up to 1.6-fold, but transforming growth factor beta (10 ng/mL) had no effect. The latent proform of recombinant (r) human MMP-20 was converted by tumor-related trypsin-2. Activated rMMP-20 did not degrade type I or type II collagen, but efficiently hydrolyzed fibronectin, type IV collagen, laminin-1 and -5, tenascin-C, and beta-casein. This implies that MMP-20 not only participates in dental matrix remodeling but is also present in tongue carcinoma cells.
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105
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Iwata K, O'Keefe GB, Karanas A. Neurologic problems associated with chronic nitrous oxide abuse in a non-healthcare worker. Am J Med Sci 2001; 322:173-4. [PMID: 11570786 DOI: 10.1097/00000441-200109000-00014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Chronic exposure to nitrous oxide (N2O) is known to be associated with hematologic and neurologic abnormalities. When this syndrome occurs, it is generally seen in health care workers, especially dentists and anesthesiologists, who have access to nitrous oxide. Here, however, we report a case of a 55-year-old non-healthcare worker who presented with multiple neurological abnormalities. His serum vitamin B12 level was low but his Shilling test was normal. His neurologic symptoms improved after cessation of inhaling nitrous oxide and starting vitamin B12 therapy. Physicians should consider nitrous oxide abuse in non-healthcare workers presenting with neurologic symptom of unclear cause.
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106
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Ishizuka O, Iwata K, Igawa Y, Nishizawa O. [Significance of PSA-density: analysis in PSA gray zone cases]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 2001; 47:611-3. [PMID: 11692595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
We studied the sensitivity and specificity of digital examination and prostate specific antigen (PSA) density to detect prostatic cancer in those patients whose PSA values are in a range of 4 to 10 ng/ml or in a gray zone. Sextant prostate biopsy revealed 14 cases (17.2%) of prostatic cancer out of 81 PSA gray zone cases. The sensitivity of digital examination was 38.5%, and the specificity was 73.0%. If we use 0.29 as a PSA density cut-off value, the sensitivity was 70.0%, and the specificity was 70.0%. At a PSA density cut off value of 0.22, we could obtain 90% sensitivity, which was considered applicable for detection of cancer in PSA gray zone cases.
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107
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Suzuki K, Iwata K, Yoshida K. Genome analysis of Agrobacterium tumefaciens: construction of physical maps for linear and circular chromosomal DNAs, determination of copy number ratio and mapping of chromosomal virulence genes. DNA Res 2001; 8:141-52. [PMID: 11572480 DOI: 10.1093/dnares/8.4.141] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The phytopathogenic bacterium Agrobacterium tumefaciens is unique in that it possesses both linear and circular DNA chromosomes in addition to a plant-tumor-inducing (Ti) plasmid. We analyzed the two chromosomal DNA molecules in strain MAFF301001, whose Ti plasmid has already been sequenced completely. Physical maps of the chromosomal DNAs were constructed by Southern hybridization experiments using Pme I and Swa I fragments and short fragments bridging the Swa I fragments with special care to avoid any missing fragment. Hybridization with 16S rDNA probe showed one rDNA locus on the linear chromosome and two loci on the circular chromosome. For this bacterium to be pathogenic, not only Ti plasmid but also chromosomal genes are required. The chromosomal virulence (chv) genes (chvA, chvB, chvD, chvE, chvG, chvH, and chvI) and the chromosomal genes affecting the virulence [acvB, pgm(exoC), glgP, miaA, and ros] were successfully mapped onto 5 different regions in the chromosomal physical maps. These chv genes and the chromosomal genes affecting the virulence other than pgm and glgP were found on the circular chromosome, whereas the pgm and glgP genes were located on the linear chromosome. In contrast to the large terminal inverted repeats of Streptomyces linear chromosomal DNA, no hybridization signal was detected between left and right terminal fragments of the linear A. tumefaciens chromosome. Quantitative analysis of DNA fragments indicated that the copy numbers of the two chromosomal DNAs and the Ti plasmid are identical.
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MESH Headings
- Agrobacterium tumefaciens/genetics
- Agrobacterium tumefaciens/pathogenicity
- Base Sequence
- Chromosomes, Bacterial/genetics
- DNA Restriction Enzymes
- DNA, Bacterial/genetics
- DNA, Bacterial/isolation & purification
- DNA, Circular/genetics
- DNA, Circular/isolation & purification
- DNA, Ribosomal/genetics
- Electrophoresis, Gel, Pulsed-Field
- Gene Duplication
- Genes, Bacterial
- Genome, Bacterial
- Physical Chromosome Mapping
- Plasmids/genetics
- Plasmids/isolation & purification
- Virulence/genetics
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108
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Takahashi K, Iwata K, Watanabe N, Hatahara T, Ohta Y, Baba K, Mishiro S. Full-genome nucleotide sequence of a hepatitis E virus strain that may be indigenous to Japan. Virology 2001; 287:9-12. [PMID: 11504536 DOI: 10.1006/viro.2001.1017] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We identified hepatitis E virus (HEV) RNA in serum from a Japanese patient with acute hepatitis, who had never been abroad. The full-genome nucleotide sequence of the HEV isolate (JRA1) from this patient was composed of 7227 nucleotides excepting the poly(A) tail and had ORF1 coding for 1703 amino acids (aa), ORF2 coding for 660 aa, and ORF3 coding for 122 aa. This Japanese strain showed approximately 87% nucleotide similarity to human and swine strains reported from the United States, while it had only 73-76% similarity to Asian and Mexican strains. Here we report the characteristics of the HEV-JRA1 isolate, which might be the first example of an indigenous strain(s) of HEV in Japan.
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109
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Iwata K, Eyles SJ, Lee JP. Exposing asymmetry between monomers in Alzheimer's amyloid fibrils via reductive alkylation of lysine residues. J Am Chem Soc 2001; 123:6728-9. [PMID: 11439074 DOI: 10.1021/ja015735y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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110
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Abstract
To evaluate the possible role of insulin, proinsulin, and amylin in the renin-angiotensin system, the direct effect of these peptides on renin release was examined using perfused kidney of rats. Renin release was significantly increased from a basal value of 6.1 +/- 1.8 to a peak value of 10.1 +/- 2.3 ng angiotensin I (Ang I)/mL/h by 0.5 nmol insulin, from 6.0 +/- 1.7 to 16.7 +/- 4.5 ng Ang I/mL/h by 1 nmol insulin, and from 6.1 +/- 1.8 to 18.0 +/- 5.5 ng Ang I/mL/h by 8 nmol insulin. Renin release was not significantly changed by perfusion of 0.05 nmol proinsulin or amylin but significantly increased from a basal value of 6.1 +/- 1.7 to a peak value of 8.1 +/- 3.6 ng Ang I/mL/h by 1 nmol proinsulin, from 5.6 +/- 1.7 to 12.1 +/- 3.8 ng Ang I/mL/h by 8 nmol proinsulin, from 5.7 +/- 1.9 to 8.2 +/- 3.5 ng Ang I/mL/h by 1 nmol amylin, and from 5.2 +/- 2.0 to 12.4 +/- 3.3 ng Ang I/mL/h by 8 nmol amylin. The concentration of cyclic adenosine monophosphate in the effluent was significantly increased from a basal value of 5.1 +/- 1.6 to a peak value of 10.6 +/- 2.5 mmol/min by 8 nmol amylin but not altered by perfusion of insulin or proinsulin. The addition of 0.05 nmol proinsulin and 0.05 nmol of amylin on 0.5 nmol insulin significantly enhanced renin release. These results indicate that insulin may play an important physiologic role in the renin-angiotensin system and suggest that proinsulin and amylin may be involved in the genesis and development of hypertension through enhancement of insulin-stimulated renin release.
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111
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Iwata K, Tazawa M, Itoh T. Turgor pressure regulation and the orientation of cortical microtubules in Spirogyra cells. PLANT & CELL PHYSIOLOGY 2001; 42:594-8. [PMID: 11427678 DOI: 10.1093/pcp/pce073] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Microtubules (MTs) of cells of Spirogyra sp. were depolymerized by treatment with amiprophos-methyl (APM) for 1 h and then reorganized in 0.30 M mannitol solution. The reorganized MTs after 1.5 h incubation showed an oblique/longitudinal orientation and then became transversely oriented as the incubation was prolonged. During this incubation, the osmotic pressure of cells was measured by the plasmolysis method. The cell osmotic pressure increased with time. The calculated turgor pressure at 1.5 h was 0.11 M (mannitol equivalent) and, at 13.5 h, 0.25 M. Similar changes in MT orientation and recovery of the turgor pressure were also observed in 0.30 M sorbitol solution. These results suggest that the MT orientation may be correlated with the turgor pressure. Among fresh water algae sensitive to a saline environment, this Spirogyra was the first species shown to have a turgor regulating mechanism, although the recovery of turgor pressure was incomplete. The recovery of turgor pressure in mannitol solutions was also observed without APM treatment.
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112
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Takahashi K, Iwata K, Matsumoto M, Matsumoto H, Nakao K, Hatahara T, Ohta Y, Kanai K, Maruo H, Baba K, Hijikata M, Mishiro S. Hepatitis C virus (HCV) genotype 1b sequences from fifteen patients with hepatocellular carcinoma: the 'progression score' revisited. Hepatol Res 2001; 20:161-171. [PMID: 11348851 DOI: 10.1016/s1386-6346(00)00141-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The genome of hepatitis C virus (HCV) associated with hepatocellular carcinoma (HCC) may have some characteristics which would barely be found in those of HCV from asymptomatic carriers (ASC). We analyzed 15 HCC patients who were infected with HCV genotype 1b (HCV-1b) for complete nucleotide sequences of the viral genomes. Of the 15 isolates, three were sequenced up to the first nucleotide of the 5'UTR, and six were sequenced to encompass the X-tail at the 3' end: sequencing of at least three-quarters of the 5'UTR and entire polyprotein-ORF was accomplished in all 15 isolates. Analyses of these sequences together with those reported previously by Nagayama et al. [Hepatology; 31 (2000) 745] suggested that nine residues (nt 119 of 5'UTR and aa 90, 434, 938, 962, 1176, 1412, 2143, and 2774 of polyprotein) might be useful to discriminate HCC-type sequences from ASC-type ones. The 'progression score' was 1.4+/-0.9 in ASC versus 3.7+/-1.5 in HCC (P=3.87E-07) when calculated with the Nagayama et al.'s seven residues, but was 1.4+/-0.6 versus 4.6+/-1.9 (P=1.33E-09) with our nine residues: a greater difference between HCC and ASC was achieved in the latter system. Further analyses, by increasing the sample size and/or by extending the comparison to include entire 5'UTR and 3'UTR/X-tail, may thus contribute to define the 'progression score' more appropriately.
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113
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Mizutani A, Kikuta H, Nakajima K, Iwata K. Nonpolarizing guided-mode resonant grating filter for oblique incidence. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2001; 18:1261-1266. [PMID: 11393618 DOI: 10.1364/josaa.18.001261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new type of guided-mode resonant grating filter is described. The filter is independent of polarization state for oblique incidence. The filter has a crossed grating structure, and the plane of incidence on the filter contains the symmetric axis of the grating structure. Theoretical considerations and numerical calculations using two-dimensional rigorous coupled-wave analysis show that a rhombic lattice structure is suitable to such filters. In this configuration an incident light wave is diffracted into the waveguide and is divided into two propagation modes whose directions are symmetric with respect to the plane of incidence. In particular, when the propagation directions of the two modes are perpendicular to each other, the fill factor of grating structure can be approximately 50%. The filter was designed for an incident angle of 45 degrees. Tolerances of setting errors and fabrication errors for this filter were estimated by numerical calculations.
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114
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Iwata K, Nakao M, Yamamoto M, Kimura M. Quantitative characteristics of alpha and theta EEG activities during sensory deprivation. Psychiatry Clin Neurosci 2001; 55:191-2. [PMID: 11422837 DOI: 10.1046/j.1440-1819.2001.00821.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Our previous study showed that theta and alpha electroencephalographic (EEG) activities occurred together during sensory deprivations (SD). The respective activities are expected to manifest different physiological states. In this study, we investigate statistical properties of both types of EEG activities during SD. Wavelet analyses of the original EEG activities during SD and the corresponding surrogation data can distinguish meaningful alpha and theta activities in the original data from accidentally detected ones. As a result, the mean duration of the theta wave is found to be longer than that of the alpha wave. This result could be useful to disclose physiological processes during SD.
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115
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Kanda K, Sato H, Kemuriyama T, Iwata K. Temporal facilitation of the flexor reflex induced by C-fiber activity: comparison between adult and aged rats. Neurosci Lett 2001; 304:49-52. [PMID: 11335052 DOI: 10.1016/s0304-3940(01)01761-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We investigated the wind-up phenomenon of the flexor reflex in adult and aged rats. The sural nerve was stimulated at C-fiber strength and reflex activity was recorded from the semitendinosus muscle. The wind-up rate, the increment rate of the C-fiber response (i.e. activity from 100 to 600 ms after stimulation) by successive stimuli (five train pulses), was decreased exponentially with increasing stimulus intervals from 3 to 20 s. The time constant of the decay for the aged rats was 9.2+/-3.2 s (mean+/-SD), which was significantly longer than for the adult rats (6.4+/-2.9 s). The findings indicate that the effects of C-fiber activation on the spinal nociceptive pathways attenuate more slowly in aged rats as compared with adult rats.
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116
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Iwata K. Are fewer patient isolations justified for active tuberculosis? ARCHIVES OF INTERNAL MEDICINE 2001; 161:1116-7. [PMID: 11322849 DOI: 10.1001/archinte.161.8.1116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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117
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Soeda S, Iwata K, Hosoda Y, Shimeno H. Daunorubicin attenuates tumor necrosis factor-alpha-induced biosynthesis of plasminogen activator inhibitor-1 in human umbilical vein endothelial cells. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1538:234-41. [PMID: 11336794 DOI: 10.1016/s0167-4889(01)00073-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The anthracycline antibiotic daunorubicin is reported to induce apoptosis in cells by triggering ceramide generation through de novo synthesis or sphingomyelin hydrolysis. Treatment of human umbilical vein endothelial cells (HUVEC) with daunorubicin markedly decreased the mRNA expression and protein release of plasminogen activator inhibitor-1 (PAI-1). This cellular event was accompanied by a significant increase in the total ceramide content in HUVEC. On the other hand, tumor necrosis factor (TNF)-alpha treatment of HUVEC led to an increase in both PAI-1 mRNA expression and protein release, and an enhancement of total ceramide content was also observed. The stimulating effect of TNF-alpha on PAI-1 synthesis was attenuated by the pretreatment of HUVEC with daunorubicin. Interestingly, the daunorubicin-induced increase in ceramide content was blocked by addition of the potent ceramide synthase inhibitor fumonisin B(1), while the TNF-alpha-induced ceramide increase was not affected by this drug. Fumonisin B(1) treatment restored the daunorubicin-induced decrease in PAI-1 release to approximately 70% of the control, but did not affect the TNF-alpha-induced increase in PAI-1 release. Thus, these data imply the possibility that the subcellular topology of ceramide production determines its lipid mediator function in the regulation of PAI-1 synthesis in HUVEC, because both TNF-alpha and daunorubicin could increase the ceramide levels.
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118
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119
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Hattori Y, Iwata K, Suzuki K, Uraji M, Ohta N, Katoh A, Yoshida K. Sequence characterization of the vir region of a nopaline type Ti plasmid, pTi-SAKURA. Genes Genet Syst 2001; 76:121-30. [PMID: 11434457 DOI: 10.1266/ggs.76.121] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We isolated a crown gall tumor-inducing nopaline type Ti plasmid from Agrobacterium tumefaciens on a Sakura Japanese cherry tree, and designated it as pTi-SAKURA. By primer walking sequencing with long PCR and a newly developed PCR subcloning technique for long insert DNA, we completed DNA sequencing of the most important functional unit, the virulence (vir) region of pTi-SAKURA, which is indispensable for T-DNA transfer into the plant's chromosomes. By homology searches with the vir genes of other bacterial plasmids, we identified 11 open reading frames (orfs) and 31 genes and 11 vir box, which are 6 bp regulatory sequences. In total, 26 vir genes, including the putative virF and virK and the main vir region, were present as the vir gene cluster. The presence of vir box, GC content, codon usage and expression analysis in these genes led us to propose a new vir region.
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120
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Matsuura A, Yasuura K, Yoshida K, Oshima H, Tomari S, Ishida H, Mori S, Fujii G, Iwata K. Transplantation of the en bloc vascular system for coronary revascularization. J Thorac Cardiovasc Surg 2001; 121:520-5. [PMID: 11241087 DOI: 10.1067/mtc.2001.112624] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Use of the free gastroepiploic artery graft for coronary revascularization has not been very popular because of its inclination toward vasospasm. We hypothesized that the cause of free gastroepiploic artery spasm was the graft damage caused by an interruption of venous drainage from the graft. To solve this problem, we developed a new method of free gastroepiploic artery grafting. METHODS From January 1997 to October 1999, 33 patients underwent coronary artery bypass grafting with the free gastroepiploic artery according to our new method. The gastroepiploic artery graft was harvested en bloc with its satellite veins. The gastroepiploic vein was anastomosed to the right atrial appendage for venous drainage simultaneously with the gastroepiploic artery being grafted in the aortocoronary position. RESULTS A total of 96 distal anastomoses were performed, including 33 free gastroepiploic artery grafts according to our method, 33 in situ left internal thoracic artery grafts, 26 saphenous vein grafts, and 4 radial artery grafts. Neither operative nor hospital death occurred. Early postoperative angiography revealed that all of the 33 free gastroepiploic artery grafts performed with our method were patent without spasm, and flow competition occurred only in 2 of those grafts. On late angiography, all 15 free gastroepiploic artery grafts were patent without spasm. CONCLUSIONS The free gastroepiploic artery grafting with venous drainage technique we developed can prevent graft spasm, leading to improved patency rate.
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121
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Ishizuka O, Iwata K, Igawa Y, Nishizawa O, Misawa K. [Laparoscopic adrenalectomy at Shinshu University School of Medicine]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 2001; 47:69-72. [PMID: 11280888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
We report our experience with transperitoneal laparoscopic adrenalectomy in 26 cases (mean age 45 years). We experienced primary aldosteronism in 19 cases, Cushing syndrome in 6 cases and non-functioning tumor in one case. There was no significant difference in the operation time between right and left, men and women, primary aldosteronism and Cushing syndrome. The blood loss decreased with training. There were no severe complications during and after the operation. The weight of the resected adrenal glands increased. The blood loss decreased significantly compared with the open surgery. Transperitoneal laparoscopic adrenalectomy is becoming the safe and standard surgery for the adrenal gland tumor, and the number of suitable cases for this procedure is expected to increase in the future.
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122
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Komuro A, Masuda Y, Iwata K, Kobayashi M, Kato T, Hidaka O, Morimoto T. Influence of food thickness and hardness on possible feed-forward control of the masseteric muscle activity in the anesthetized rabbit. Neurosci Res 2001; 39:21-9. [PMID: 11164250 DOI: 10.1016/s0168-0102(00)00192-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The facilitatory masseteric muscle response (FMR) elicited by polyurethane foam strip application between the opposing molars during cortically-induced rhythmic jaw movements (CRJMs) was induced earlier than masticatory force onset. The occurrence of this early response of the FMR (e-FMR) could not be explained by a simple reflex mechanism. One possible mechanism of the e-FMR is the involvement of a feed-forward control mechanism of the masticatory jaw movement. In the present study, experimentally designed polyurethane foam strips with various thickness and hardness were applied during CRJMs and analyzed in terms of how the e-FMR was modulated by the food hardness and thickness. The FMR onset was not related to the strip thickness or the strip hardness. However, the magnitude of the e-FMR increased in a thickness and a hardness-dependent manner. The sensory information of the food properties in the masticatory cycle may make the FMR adequate to chewing of the food in the following cycle, and such modulation may help chewing rhythms remain stable.
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123
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Masuda Y, Kato T, Hidaka O, Matsuo R, Inoue T, Iwata K, Morimoto T. Neuronal activity in the putamen and the globus pallidus of rabbit during mastication. Neurosci Res 2001; 39:11-9. [PMID: 11164249 DOI: 10.1016/s0168-0102(00)00186-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The pattern of jaw movements is changed during a masticatory sequence from ingestion of food to its deglutition. The masticatory sequence is divided into three distinct stages in the rabbit. However, the neural mechanism involved in the alteration of the masticatory stages is still unknown. This study was designed to determine whether neuronal activity in the putamen and globus pallidus is related to the alteration of the masticatory stages. Fifty-three percent of the recorded neurons showed significant alterations of activity during mastication. Of these neurons, 16% changed their firing frequency throughout the masticatory sequence (sequence-related neurons) and 84% changed their firing frequency with the transition of the masticatory stages (stage-related neurons). The stage-related neurons were classified into two groups based on their neuronal activity patterns observed during mastication, i.e. simple type and complex type. The former are the neurons that were either facilitated or inhibited once during mastication, and the latter are those showing the facilitation or inhibition twice or more during mastication. Complex-type neurons were observed more frequently in the globus pallidus than in the putamen. These results suggest that the basal ganglia is involved in mastication and may related to the transition between the masticatory stages.
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Hattori Y, Uraji M, Suzuki K, Ohta N, Iwata K, Kato A, Yoshida K. Gene list on a plant tumor-inducing plasmid, pti-SAKURA in Agrobacterium tumefaciens MAFF301001. DNA Res 2000; 7:371-80. [PMID: 11214973 DOI: 10.1093/dnares/7.6.371] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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125
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Abstract
To examine the transition to ureogenesis, the gobiid fish Mugilogobius abei was immersed in 2 mmol l(−)(1) NH(4)HCO(3) or a (15)N-labelled ammonia solution [1 mmol l(−)(1) ((15)NH(4))(2)SO(4), pH 8.0] for 4–8 days. When exposed to 2 mmol l(−)(1) NH(4)HCO(3) or (15)N-labelled ammonia solution for 4 days, the rate of urea excretion increased to seven times that of the control (in 20 % synthetic sea water) and remained at this level for 4 days. The proportion of nitrogen excreted as urea reached 62 % of total nitrogen excretion (ammonia-N + urea-N). (15)N-enrichment of the amide-N in glutamine in the tissues of fish exposed to (15)N-labelled ammonia was virtually the same as that of ammonia-N: i.e. approximately twice that of urea-N in the excreta and the tissues. Glutamine contents and glutamine synthetase activities in the liver and muscle increased greatly following exposure to ammonia. Urea and citrulline contents in the muscle and whole body of the exposed fish increased significantly, whereas uric acid contents remained unchanged. Carbamoyl phosphate synthetase III (CPSase III) mRNA expression and CPSase III activity were detected in the muscle, skin and gill, but levels were negligible in the liver. Furthermore, all other ornithine-urea cycle (O-UC) enzymes were also detected in muscle, skin and gill. Thus, M. abei clearly shows the transition from ammoniotely to ureotely under ammonia-loading condition and is able to produce urea mainly via the O-UC operating in multiple non-hepatic tissues as a means for ammonia detoxification.
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126
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Wang T, Aoki T, Iwata K, Takata T, Uchida T, Knäuper V, Llano E, Okada Y, Bartlett JD. One-step sandwich enzyme immunoassay using monoclonal antibodies for detection of human enamelysin (MMP-20). Eur J Oral Sci 2000; 108:530-7. [PMID: 11153928 DOI: 10.1034/j.1600-0722.2000.00922.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A one-step sandwich enzyme immunoassay (EIA) system for human matrix metalloproteinase 20 (MMP-20, enamelysin) was established by use of a solid-phase monoclonal antibody and a separate peroxidase-labeled monoclonal antibody. The EIA system was shown to be sensitive and quantitative for the detection of MMP-20. As little as 1.0 ng/ml (50 pg/assay) of MMP-20 protein could be reliably detected. The EIA system was linear over a range of 2.5-160 ng/ml (125-8,000 pg/assay), and the EIA system was versatile in that it was capable of detecting with equal sensitivity proMMP-20, active MMP-20, and MMP-20 with COOH-terminal deletions. The EIA system was validated by the successful detection of MMP-20 in the culture medium of Chinese hamster ovary cells (CHO-K1) that were transfected with an MMP-20 expression vector. No MMP-20 was detected in normal human serum, normal saliva, or in selected tumors. However, when recombinant human MMP-20 was added to human saliva, the EIA system did detect quantifiable amounts of the MMP-20, indicating that the system will work within the framework of complex in biological fluids.
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127
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Elnemr A, Ohta T, Iwata K, Ninomia I, Fushida S, Nishimura G, Kitagawa H, Kayahara M, Yamamoto M, Terada T, Miwa K. PPARgamma ligand (thiazolidinedione) induces growth arrest and differentiation markers of human pancreatic cancer cells. Int J Oncol 2000; 17:1157-64. [PMID: 11078801 DOI: 10.3892/ijo.17.6.1157] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The aim of this study was to examine whether a specific PPARgamma ligand can inhibit the growth of human pancreatic cancer cells through induction of terminal differentiation. PPARgamma was expressed in five human pancreatic cancer cell lines: Capan-1, AsPC-1, BxPC-3, PANC-1, and MIA PaCa-2. Treatment of these cells with a specific PPARgamma ligand, thiazolidinedione (TZD), resulted in inhibition of both cellular and clonogenic growth, and G1 cell cycle arrest. Finally, thiazolidinedione treatment resulted in induction of p21WAF-1 and increased expression of differentiation markers. These results suggest that thiazolidinedione treatment inhibits growth and induces cellular differentiation in pancreatic cancer cells and thereby reduces their development in favor of differentiated and stable cell phenotype.
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MESH Headings
- Adenocarcinoma/genetics
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/genetics
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Antineoplastic Agents/pharmacology
- Blotting, Western
- Carcinoma/genetics
- Carcinoma/metabolism
- Carcinoma/pathology
- Cell Cycle/drug effects
- Cell Differentiation/drug effects
- Cell Division/drug effects
- Cyclin-Dependent Kinase Inhibitor p21
- Cyclins/biosynthesis
- Cyclins/genetics
- Gene Expression Regulation, Neoplastic/drug effects
- Growth Inhibitors/pharmacology
- Humans
- Ligands
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/drug effects
- Neoplasm Proteins/genetics
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Receptors, Cytoplasmic and Nuclear/biosynthesis
- Receptors, Cytoplasmic and Nuclear/drug effects
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- Thiazoles/pharmacology
- Thiazolidinediones
- Transcription Factors/biosynthesis
- Transcription Factors/drug effects
- Transcription Factors/genetics
- Transcription Factors/physiology
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/metabolism
- Tumor Cells, Cultured/pathology
- Tumor Stem Cell Assay
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128
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Kamei T, Kumano H, Iwata K, Nariai Y, Matsumoto T. The effect of a traditional Chinese prescription for a case of lung carcinoma. J Altern Complement Med 2000; 6:557-9. [PMID: 11152062 DOI: 10.1089/acm.2000.6.557] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To examine the effectiveness of Ninjin Yoei To (NYT; Ren-Shen-Yang-Rong-Tang in Chinese medicine; Kotaro Pharmaceutical Co., Ltd., Osaka, Japan), one of the traditional herbal medicines, against lung carcinoma. SETTING The Nursing Center Himawari DESIGN, PATIENT, AND PREPARATION: The regular dosage of NYT (15 g/d) was prescribed for 7 weeks to one elderly patient with lung carcinoma. The daily standard dose of NYT is prepared from dried extract obtained from 12 crude natural substances, ginseng, cinnamon bark, Japanese angelica root, astragalus root, peony root, citrus unshiu peel, rehmannia root, polygala root, atractylodes rhizome, schisanda fruit, poria sclerotium, and glycyrrhiza. NYT is certified by the Japanese Ministry of Health and Welfare. RESULTS The tumor marker levels (CEA and CA19-9) decreased and the scores of yin-yang and xu-shi inverted from negative and positive during 7 weeks. The patient's cough disappeared and her appetite recovered. CONCLUSION NYT has a positive effect on life expectancy for patients with malignancy. The diagnostic scoring system in yin-yang and xu-shi and prescription of Chinese herb may be available to gain control over a patient's health.
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129
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Kenshalo DR, Iwata K, Sholas M, Thomas DA. Response properties and organization of nociceptive neurons in area 1 of monkey primary somatosensory cortex. J Neurophysiol 2000; 84:719-29. [PMID: 10938299 DOI: 10.1152/jn.2000.84.2.719] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The organization and response properties of nociceptive neurons in area 1 of the primary somatosensory cortex (SI) of anesthetized monkeys were examined. The receptive fields of nociceptive neurons were classified as either wide-dynamic-range (WDR) neurons that were preferentially responsive to noxious mechanical stimulation, or nociceptive specific (NS) that were responsive to only noxious stimuli. The cortical locations and the responses of the two classes of neurons were compared. An examination of the neuronal stimulus-response functions obtained during noxious thermal stimulation of the glabrous skin of the foot or the hand indicated that WDR neurons exhibited significantly greater sensitivity to noxious thermal stimuli than did NS neurons. The receptive fields of WDR neurons were significantly larger than the receptive fields of NS neurons. Nociceptive SI neurons were somatotopically organized. Nociceptive neurons with receptive fields on the foot were located more medial in area 1 of SI than those with receptive fields on the hand. In the foot representation, the recording sites of nociceptive neurons were near the boundary between areas 3b and 1, whereas in the hand area, there was a tendency for them to be located more caudal in area 1. The majority of nociceptive neurons were located in the middle layers (III and IV) of area 1. The fact that nociceptive neurons were not evenly distributed across the layers of area 1 suggested that columns of nociceptive neurons probably do not exist in the somatosensory cortex. In electrode tracks where nociceptive neurons were found, approximately half of all subsequently isolated neurons were also classified as nociceptive. Low-threshold mechanoreceptive (LTM) neurons were intermingled with nociceptive neurons. Both WDR and NS neurons were found in close proximity to one another. In instances where the receptive field shifted, subsequently isolated cells were also classified as nociceptive. These data suggest that nociceptive neurons in area 1 of SI are organized in vertically orientated aggregations or clusters in layers III and IV.
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130
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Abe Y, Shoji T, Matsubara M, Yoshida M, Sugata S, Iwata K, Suzuki H. Chiral discrimination of N-carbazole-carbonyl derivatives of alpha-amino acids with a short linear alkyl side chain by bovine serum albumin. Chirality 2000; 12:565-7. [PMID: 10861956 DOI: 10.1002/1520-636x(2000)12:7<565::aid-chir3>3.0.co;2-#] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chiral discrimination of racemic carbazole carbonyl (CC)-amino acids with linear alkyl sidechain (C(1)-C(4)) by bovine serum albumin (BSA) was investigated by competitive replacement experiments using dansyl-L-proline and dansyl-D-norvaline as fluorescent probes. It was found that the CC derivatives of the D-forms of alanine (C(1)), amino butyric acid (C(2)), norvaline (C(3)), and norleucine (C(4)) bound to the dansyl-L-proline site much more strongly than their L-forms, whereas the interactions between both enantiomers of these amino acids with dansyl-D-norvaline site were slight.
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131
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Kato H, Igawa Y, Kiyokawa H, Iwata K, Nishizawa O. Continent ileal pouch using the serous-lined principle. Eur Urol 2000; 38:100-3. [PMID: 10859450 DOI: 10.1159/000020260] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The flap valve principle is not easily applicable to an ileal pouch since a submucosal tunnel is difficult to create. We attempted to construct an ileal pouch with an umbilical stoma applying the serous-lined principle for both ureteral implantation and construction of a continent valve. METHODS In 9 patients, a continent pouch with an umbilical stoma was created entirely from an ileal segment. Adopting the serous-lined principle, a continent valve was created by appendix in 2 cases, tapered ileum in 3 cases, and reconfigured ileum in 4 cases. These were implanted into the anterior suture line of the pouch and embedded into the serous-lined tunnel formed by the pouch wall. RESULTS Patients can catheterize the pouch easily with a 14-Fr catheter. Postoperatively, pouch capacity is over 400 ml with complete continence. CONCLUSION This technique can provide a simple and effective continent ileal pouch facilitating umbilical anastomosis. As a continent valve, the reconfigured ileal segment seems most useful for application of the serous-lined principle.
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132
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Iwata K, Fons P, Niki S, Yamada A, Matsubara K, Nakahara K, Takasu H. Improvement of Electrical Properties in ZnO Thin Films Grown by Radical Source(RS)-MBE. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/1521-396x(200007)180:1<287::aid-pssa287>3.0.co;2-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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133
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Soeda S, Kozako T, Iwata K, Shimeno H. Oversulfated fucoidan inhibits the basic fibroblast growth factor-induced tube formation by human umbilical vein endothelial cells: its possible mechanism of action. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1497:127-34. [PMID: 10838166 DOI: 10.1016/s0167-4889(00)00052-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have previously demonstrated that chemically oversulfated fucoidan (OSF) but not native fucoidan (NF) effectively suppresses the tube structure formation by human umbilical vein endothelial cells (HUVEC) on the basement membrane preparation, Matrigel. In this study, using more defined systems where basic fibroblast growth factor (bFGF) induces the tube formation by HUVEC on collagen gel, we investigated the mechanism responsible for the inhibition of angiogenesis by OSF in vitro. Unlike NF and desulfated fucoidan (desF), OSF potently inhibited the bFGF-induced HUVEC migration and tube formation. ELISA for tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) in the culture media indicated that OSF increased the bFGF-induced release of PAI-1 antigen, but not of t-PA antigen. Analyses of the binding of bFGF to HUVEC surfaces and the following protein tyrosine phosphorylation revealed that OSF could promote the cell binding and autophosphorylation of 140 and 160 kDa receptors. In heparitinase-treated HUVEC, contrarily, the bFGF binding and PAI-1 release were decreased by OSF. These results suggest that OSF is a highly sulfated unique polysaccharide that can promote the binding of bFGF to the heparan sulfate molecules required for binding to the high affinity receptors with tyrosine kinase activity. The resultant increase in PAI-1 release may play a key role for the prevention of cell migration accompanied by matrix proteolysis.
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134
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Tanaka M, Iwata K, Kuzuu N. High-precision computer simulations of entangled polymer chains: 1. Determination of entanglement parameters of bond-fluctuation model. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s1089-3156(99)00045-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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135
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Iwata K, Nakao M, Yamamoto M, Kimura M. Differentiation of physiological states under sensory deprivation. Methods Inf Med 2000; 39:168-70. [PMID: 10892256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We attempt to differentiate the physiological state during sensory deprivation (SD) from normal sleep and wakefulness in terms of electroencephalogram (EEG) and heart rate variability (HRV) dynamics. Kullback-Leibler (K-L) divergence is employed to quantify differences between their state-dependent dynamics. As a result, the dynamics of EEG and HRV during SD are found to be far distant from any representative dynamics of natural states of sleep and wakefulness. However, relatively speaking, the findings in SD can be categorized into two patterns. (a) The dynamics of HRV during SD is similar to that of rapid eye movement (REM) sleep, and the dynamics of EEG during SD is similar to that of wakefulness. (b) The dynamics of both HRV and EEG during SD are similar to that of REM. Such dissociation between states classified by EEG and HRV dynamics frequently takes place during SD. These findings suggest the peculiarity of the physiological state during the SD distinct from sleep and wakefulness.
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136
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Tanaka M, Kuzuu N, Imai S, Iwata K. Correspondence relation with respect to entanglement among different simulation models: comparison between bead-spring and bond fluctuation model. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s1089-3156(99)00046-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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137
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Zhang S, Iwata K, Lachenmann MJ, Peng JW, Li S, Stimson ER, Lu Y, Felix AM, Maggio JE, Lee JP. The Alzheimer's peptide a beta adopts a collapsed coil structure in water. J Struct Biol 2000; 130:130-41. [PMID: 10940221 DOI: 10.1006/jsbi.2000.4288] [Citation(s) in RCA: 276] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The self-assembly of the soluble peptide Abeta into Alzheimer's disease amyloid is believed to involve a conformational change. Hence the solution conformation of Abeta is of significant interest. In contrast to studies in other solvents, in water Abeta is collapsed into a compact series of loops, strands, and turns and has no alpha-helical or beta-sheet structure. Conformational stabilization is primarily attributed to van der Waals and electrostatic forces. A large conspicuous uninterrupted hydrophobic patch covers approximately 25% of the surface. The compact coil structure appears meta-stable, and because fibrillization leads to formation of intermolecular beta-sheet secondary structure, a global conformational rearrangement is highly likely. A molecular hypothesis for amyloidosis includes at least two primary driving forces, changes in solvation thermodynamics during formation of amyloid deposits and relief of internal conformational stress within the soluble precursor during formation of lower-energy amyloid fibrils.
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138
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Sugiyama T, Shimizu M, Ohnishi H, Noguchi N, Iwata K, Kojima Y, Watanabe Y, Kawase K, Fukutomi Y, Yamauchi O, Yasuda S, Yamada M, Kobayashi S, Kojima M. [Clinical evaluation in oral lichen planus with chronic hepatitis C: the role of interferon treatment]. NIHON SHOKAKIBYO GAKKAI ZASSHI = THE JAPANESE JOURNAL OF GASTRO-ENTEROLOGY 2000; 97:568-74. [PMID: 10846411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Hepatitis C virus (HCV) infection induces a variety of extrahepatic manifestations such as oral lichen planus (OLP). To clarify the role of HCV in the development of OLP, we investigated the occurrence of OLP in patients with chronic hepatitis C treated with interferon (IFN). Of 275 patients with chronic hepatitis C, 6 developed OLP during the IFN treatment. However, OLP developed in none of 230 patients with chronic hepatitis C who did not undergo the IFN therapy. The IFN treatment in chronic hepatitis C patients developed OLP significantly, as compared with the non-treated group (p < 0.05). 4 of 6 patients who developed OLP during the IFN treatment had a complete response with normalization of ALT levels and undetectable HCV RNA after the treatment. There were no significant correlations between the effect of the IFN treatment and outcome of OLP. Furthermore, 3 of the 6 patients developed OLP, when serum HCV RNA became negative. These results suggest that direct viral factors may not be important in the pathogenesis of OLP in patients with chronic hepatitis C. Immunological changes caused by IFN may play a role in the development of OLP associated with HCV infection.
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139
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Tharavichitkul P, Kaneko A, Hashimoto M, Toyooka K, Hasegawa M, Iwata K, Kuratsuji T, Yazaki Y, Sirisanthana T, Kirikae T. Comparison of genomic DNA fingerprinting using pulsed-field gel electrophoresis and antibiotic susceptibility of clinical isolates of methicillin-resistant Staphylococcus aureus between Chiang Mai and Tokyo. Jpn J Infect Dis 2000; 53:86-7. [PMID: 10871927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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140
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Ikeda T, Iwata K, Murakami H. Inhibitory effect of metformin on intestinal glucose absorption in the perfused rat intestine. Biochem Pharmacol 2000; 59:887-90. [PMID: 10718348 DOI: 10.1016/s0006-2952(99)00396-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
To investigate the effect of metformin on intestinal glucose absorption, a perfusion study of the intestine was performed in the rat. Male Wistar albino rats (8 weeks old) were used in the present study. The glucose absorption by the perfused intestine (788.1+/-81.9 micromol/30 min) was not changed significantly by the direct addition of metformin (90 microg/mL) to the perfusing medium (737.0+/-118.2 micromol/30 min) or by intraduodenal metformin (250 mg/kg in saline solution) infusion (772.8+/-106.3 micromol/30 min). In rats orally administered metformin (250 mg/kg) for 5 days, glucose absorption by the perfused intestine (375.0+/-164.3 micromol/30 min) was significantly (P<0.001) lower than that in control rats (811.0+/-83.1 micromol/30 min). These results indicate that metformin had a significant effect on the digestive tract, and that metformin treatment exerted an inhibitory effect on intestinal glucose absorption in the rat.
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141
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Iwata K, Kawasaki K, Shigesada N. A dynamical model for the growth and size distribution of multiple metastatic tumors. J Theor Biol 2000; 203:177-86. [PMID: 10704301 DOI: 10.1006/jtbi.2000.1075] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Metastasis is the spread of tumors culminating in the establishment of one or more secondary tumors at remote sites. In deciding the best treatment for cancer therapy, estimations of the colony size of metastatic tumors and predictions of the future spread of colonies are needed. A dynamical model for the colony size distribution of multiple metastatic tumors is presented here. The dynamics is described by equations that incorporate both the colonization by metastasis and the growth of each colony. When the colony growth is subject to the Gompertz function, the explicit solution obtained tends to an asymptotic stable distribution that shows a monotonically decreasing or U-shaped pattern according to the values of clinically significant parameters, such as the colonization coefficient and the fractal dimension of blood vessels. This predicted colony size distribution agrees well with successive data of a clinically observed size distribution of multiple metastatic tumors of liver cancer. The combined analysis of the theoretical colony size distribution and clinical data will give useful information on the diagnosis and the therapy for cancer patients.
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142
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Miki K, Iwata K, Tsuboi Y, Morimoto T, Kondo E, Dai Y, Ren K, Noguchi K. Dorsal column-thalamic pathway is involved in thalamic hyperexcitability following peripheral nerve injury: a lesion study in rats with experimental mononeuropathy. Pain 2000; 85:263-71. [PMID: 10692627 DOI: 10.1016/s0304-3959(99)00279-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A total of 68 neurons were recorded from the ventro-postero-lateral nucleus of thalamus (VPL) in rats with a unilateral chronic constriction injury (CCI) of the sciatic nerve (n=20), sham operation (n=24) and naive rats (n=24), and effects of the lesion of dorsal column (DC) pathway [DC lesion or DC+gracile nucleus lesions] on VPL nucleus neuronal activities were studied. In the VPL nucleus contralateral to the CCI (receiving input from the injured nerve), response latencies of low threshold mechanoreceptive (LTM) and wide dynamic range (WDR) neurons to electrical stimulation of the sciatic nerve were significantly longer than that in the contralateral VPL nucleus receiving input from the sham-operated side (P<0.05). In contrast, response latencies of LTM and WDR neurons to DC stimulation were not different between the sham operated and CCI sides (0.05). Background activity of WDR neurons was significantly higher in the VPL nucleus contralateral to the CCI side when compared to neurons in the VPL nucleus contralateral to the sham operated side and in naive animals. Responses of LTM and WDR neurons to innocuous mechanical stimulation of the receptive fields were significantly decreased after DC and DC+gracile nucleus lesions in all animals. However, the responses of WDR neurons to noxious stimuli were selectively reduced only in rats with CCI by DC and DC+gracile nucleus lesions (P<0.05). The decrease in noxious stimulus-evoked responses of WDR neurons in the VPL nucleus contralateral to the CCI side after DC and DC+gracile nucleus lesions was greater than that in the VPL nucleus contralateral to the sham operated side and naive animals. These results indicated that DC and DC+gracile nucleus lesions produced selective and stronger effect on noxious responses of VPL nucleus WDR neurons receiving input from the site of nerve injury. The findings suggest that the gracile nucleus-thalamic pathway conveys, or modulates, nociceptive information to the VPL nucleus following peripheral nerve injury, resulting in an increase in VPL nucleus response to noxious stimuli that contributes to the development of mechanical hyperalgesia.
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143
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Hijikata M, Iwata K, Ohta Y, Nakao K, Matsumoto M, Matsumoto H, Kanai K, Baba K, Samokhvalov EI, Mishiro S. Genotypes of TT virus (TTV) compared between liver disease patients and healthy individuals using a new PCR system capable of differentiating 1a and 1b types from others*. Arch Virol 2000; 144:2345-54. [PMID: 10664388 DOI: 10.1007/s007050050648] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
TT virus (TTV) lacks obvious pathogenicity; almost all of the infected hosts are symptom-free. A possibility remains, however, that certain strains can cause liver disease while most others are non-pathogenic. Genotypes 1 a and 1 b have been proposed to contain such pathogenic strains. To test this possibility, we constructed a PCR system capable of detecting TTV of the 1 a and 1 b genotypes differentially from the other genotypes, and compared the frequencies of these genotypes between patients with liver disease of unknown etiology (n=42) and healthy individuals (n=50). The assay comprised 3 steps: i) PCR to amplify a 3.2-kb fragment using universal primers; ii) 2nd-round PCR, starting from the 3.2-kb amplicon, for a approximately 280-nt fragment by use of genotype 1-specific primers; and iii) digestion of the approximately 280-nt amplicon with MboI and BanI to discriminate between 1 a and 1 b. Eventually, 40 (95%) of the patients and 47 (94%) of the controls were positive for the 3.2-kb amplicon, and the 1 a, 1 b, 1 a+1 b, and non-1 genotypes of TTV were found in 2 (5%) vs 4 (9 percent), 5 (13%) vs 4 (9%), 1 (3%) vs 1 (2%) and 32 (80%) vs 38 (81%) of the 40 patients and 47 controls, respectively: the distribution was almost identical between the two groups. The hypothesis that the genotype 1 of TTV may be more closely associated with liver disease than other genotypes was not supported by this study.
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144
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Hiraga S, Kaji T, Ueda Y, Zisaki F, Iwata K, Koizumi F, Okada Y, Katsuda S, Nakanishi I. Modulation of collagen synthesis by tumor necrosis factor alpha in cultured vascular smooth muscle cells. Life Sci 2000; 66:235-44. [PMID: 10665999 DOI: 10.1016/s0024-3205(99)00586-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Collagen synthesis in vascular smooth muscle cells (SMCs) after exposure to tumor necrosis factor alpha (TNF-alpha) was investigated using a culture system. The synthesis of collagenase-digestible proteins (CDP) and noncollagenous proteins (NCP) was evaluated by the [3H]proline incorporation. It was shown that TNF-alpha markedly suppresses the incorporation of [3H]proline into both CDP and NCP in confluent cultures of SMCs but not in sparse cultures of the cells. Such a marked suppression by TNF-alpha was not observed in confluent bovine aortic endothelial cells and human fibroblastic IMR-90 cells. In confluent SMCs, the synthesis of CDP was more strongly inhibited by TNF-alpha than that of NCP. When the CDP synthesis was stimulated by transforming growth factor beta, TNF-alpha suppressed the stimulation in both confluent and sparse SMCs. Human SMCs synthesized types I, III, IV and V collagens; TNF-alpha markedly decreased the relative proportion of types IV and V. It was therefore suggested that TNF-alpha modulates the collagen synthesis by SMCs depending on their cell density and modifies the formation of atherosclerotic lesions.
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145
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Suzuki K, Hattori Y, Uraji M, Ohta N, Iwata K, Murata K, Kato A, Yoshida K. Complete nucleotide sequence of a plant tumor-inducing Ti plasmid. Gene 2000; 242:331-6. [PMID: 10721727 DOI: 10.1016/s0378-1119(99)00502-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Crown gall tumor disease in dicot plants is caused by Agrobacterium tumefaciens harboring a giant tumor-inducing (Ti) plasmid. Here, for the first time among agrobacterial plasmids, the nucleotide sequence of a typical nopaline-type Ti plasmid (pTi-SAKURA) was determined completely. In total, 195 open reading frames (ORFs) were estimated in the 206479 bp long sequence. 20 genes for conjugation, three for replication, 22 for pathogenesis and 37 for genetic colonization of host plants were found within two-thirds of the plasmid. These genes formed seven functional gene clusters with narrow inter-cluster spaces. In the remaining one-third of the plasmid, novel genes including homologs of mutT, Rhizobium nodQ and Sphingomonas ligE genes were found, which are likely to be responsible for the broad host range. Restriction fragment length variation indicates extreme plasticity of the part required for conjugational gene transfer and the above-mentioned one-third of the plasmid, even among closely related Ti plasmids.
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146
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Iwata K. Modulation of dorsal horn nociceptive neurons following cutaneous inflammation in the aged rats. Neurosci Res 2000. [DOI: 10.1016/s0168-0102(00)81587-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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147
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Shiina T, Tamiya G, Oka A, Takishima N, Yamagata T, Kikkawa E, Iwata K, Tomizawa M, Okuaki N, Kuwano Y, Watanabe K, Fukuzumi Y, Itakura S, Sugawara C, Ono A, Yamazaki M, Tashiro H, Ando A, Ikemura T, Soeda E, Kimura M, Bahram S, Inoko H. Molecular dynamics of MHC genesis unraveled by sequence analysis of the 1,796,938-bp HLA class I region. Proc Natl Acad Sci U S A 1999; 96:13282-7. [PMID: 10557312 PMCID: PMC23939 DOI: 10.1073/pnas.96.23.13282] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The intensely studied MHC has become the paradigm for understanding the architectural evolution of vertebrate multigene families. The 4-Mb human MHC (also known as the HLA complex) encodes genes critically involved in the immune response, graft rejection, and disease susceptibility. Here we report the continuous 1,796,938-bp genomic sequence of the HLA class I region, linking genes between MICB and HLA-F. A total of 127 genes or potentially coding sequences were recognized within the analyzed sequence, establishing a high gene density of one per every 14.1 kb. The identification of 758 microsatellite provides tools for high-resolution mapping of HLA class I-associated disease genes. Most importantly, we establish that the repeated duplication and subsequent diversification of a minimal building block, MIC-HCGIX-3.8-1-P5-HCGIV-HLA class I-HCGII, engendered the present-day MHC. That the currently nonessential HLA-F and MICE genes have acted as progenitors to today's immune-competent HLA-ABC and MICA/B genes provides experimental evidence for evolution by "birth and death," which has general relevance to our understanding of the evolutionary forces driving vertebrate multigene families.
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148
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Iwata K, Hozumi K, Iihara A, Nomizu M, Sakairi N, Nishi N. Mechanism of salmon sperm decondensation by nucleoplasmin. Int J Biol Macromol 1999; 26:95-101. [PMID: 10517515 DOI: 10.1016/s0141-8130(99)00071-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Removal of protamine from DNA-protamine (salmine, protamine from salmon sperm) complexes by nucleoplasmin was examined and compared with that of poly-L-glutamic acid (PLGA) using turbidity and ethidium bromide (EB) treatment methods. When nucleoplasmin or PLGA was added to a DNA-protamine complex solution, turbidity was decreased and the amount of EB intercalated into DNA was increased. These results suggest that nucleoplasmin and PLGA can remove protamine from DNA-protamine complexes. The effect of nucleoplasmin was more potent than that of PLGA. Direct interaction of nucleoplasmin with protamine was confirmed by mixing experiments using circular dichroism (CD) and fluorescence spectroscopies. Results suggest that nucleoplasmin is bound to protamine in a 1:1 ratio and that Trp126 is located near a hydrophilic region containing a polyglutamic acid tract of nucleoplasmin which was obviously influenced by its binding with protamine. It would appear that the polyglutamic acid tract in nucleoplasmin plays a critical role for binding with protamine.
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149
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Iwata K, Tashiro A, Tsuboi Y, Imai T, Sumino R, Morimoto T, Dubner R, Ren K. Medullary dorsal horn neuronal activity in rats with persistent temporomandibular joint and perioral inflammation. J Neurophysiol 1999; 82:1244-53. [PMID: 10482744 DOI: 10.1152/jn.1999.82.3.1244] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Studies at spinal levels indicate that peripheral tissue or nerve injury induces a state of hyperexcitability of spinal dorsal horn neurons that participates in the development of persistent pain and hyperalgesia. It has not been demonstrated that persistent injury in the orofacial region leads to a similar state of central hyperexcitability in the trigeminal system. The purpose of the present study was to conduct a parametric analysis of the response properties of nociceptive and nonnociceptive neurons in trigeminal nucleus caudalis (medullary dorsal horn, MDH) in a rat model of persistent orofacial inflammation. Neurons were recorded extracellularly and classified as low-threshold mechanoreceptive (LTM, n = 49), wide dynamic range (WDR, n = 82), and nociceptive-specific (NS, n = 11) neurons according to their response properties to mechanical stimuli applied to their cutaneous receptive fields (RFs). The inflammation was induced 24 h before the recordings by injecting complete Freund's adjuvant (CFA) into the temporomandibular joint (TMJ) capsule or the perioral (PO) skin. The mean areas of the high-threshold RFs of WDR neurons in TMJ (8.66 +/- 0.61 cm(2), n = 25) and PO (5.61 +/- 2.07 cm(2), n = 25) inflamed rats were significantly larger than those in naive rats (1.10 +/- 0. 16 cm(2), n = 32). The mean RF size in TMJ-inflamed rats also was significantly larger than that in PO-inflamed rats (P < 0.01). Furthermore the mean area of the RFs of NS neurons (3.74 +/- 1.44 cm(2), n = 5) was significantly larger in TMJ inflamed rats as compared with naive rats (0.4 +/- 0.09 cm(2), n = 3) (P < 0.05). The background activity in the TMJ- and PO-inflamed rats was generally greater in WDR and NS neurons, but less in LTM neurons, when compared with naive rats. The responses of WDR neurons to noxious mechanical stimuli were increased significantly in TMJ-inflamed rats (P < 0.05) as compared with naive rats. WDR neuronal responses to mechanical stimulation also were increased in PO-inflamed rats but to a lesser extent than in TMJ-inflamed rats. The injection of CFA into the TMJ or PO skin resulted in reduced responses of LTM neurons to mechanical stimuli. The responses of MDH nociceptive neurons to 48-55 degrees C heating were greater in inflamed rats as compared with naive rats. A subpopulation of WDR neurons recorded from TMJ (n = 4 of 10)- or PO (n = 3 of 13)-injected rats responded to cooling in addition to heating of the RFs but did not grade their responses with changes in stimulus intensity. These results indicate that persistent orofacial inflammation produced hyperexcitability of MDH nociceptive neurons. TMJ inflammation resulted in more robust changes in MDH nociceptive neurons as compared with PO inflammation, consistent with previous studies of increased inflammation, increased MDH Fos-protein expression, and increased MDH preprodynorphin mRNA expression in this deep tissue orofacial model of pain and hyperalgesia. The inflammation-induced MDH hyperexcitability may contribute to mechanisms of persistent pain associated with orofacial deep tissue painful conditions.
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Abe Y, Fukui S, Koshiji Y, Kobayashi M, Shoji T, Sugata S, Nishizawa H, Suzuki H, Iwata K. Enantioselective binding sites on bovine serum albumin to dansyl amino acids. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1433:188-97. [PMID: 10446371 DOI: 10.1016/s0167-4838(99)00135-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The enantioselective binding sites on bovine serum albumin were examined by HPLC using 19 racemic 5-N, N-dimethylamino-1-naphthalenesulfonyl derivatives of alpha-amino acids (dansyl amino acids) as chiral probes. On a bovine serum albumin bonded chiral stationary phase, seven L-forms eluted faster than their D-forms, while ten D-forms eluted before their L-forms. It was speculated that either two classes or two different binding sites exist on bovine serum albumin which can be distinguished by N-dansyl-L-proline and N-dansyl-D-norvaline. This was confirmed by fluorometric experiments where non-fluorescent 1-naphthalenesulfonyl derivatives were synthesized and competitive adsorption experiments were performed.
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