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101.
Masato Matsuda Mika Sato Hiroki Sakata Takahisa Ogawa Ken-ichiro Yamamoto Taiji Yakushiji Makoto Fukuda Takehiro Miyasaka Kiyotaka Sakai 《Journal of artificial organs》2008,11(3):148-155
When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration. 相似文献
102.
Hiroshi Shuto Hisashi Noguchi Hikaru Nishikata Kenji Takizawa Chizuru Shuto Makoto Nagata Yoshinori Terashi Michiya Yamaguchi Takao Takizawa Kensuke Watanabe Kaoru Tosaka Masahiko Okano Akira Koizumi 《Arerugī》2007,56(7):714-720
In general, steroid is mainly used as anti-inflammatory action in case of allergic diseases. As one of the side effects of inhalation steroid, a report is given below regarding buccal capsule/esophageal candidiasis. The patient came to the hospital with the chief complaint regarding passage dysphagia in the time of deglutition; pharyngitis and esophageal candidiasis were found by endoscopy of upper gastrointestinal tract.The interview after the endoscopy revealed that the patient, a 69-year-old female was diagnosed as chronic perennial allergic rhinitis a few years ago, and had been inhaling rhinenchysis Beclometasone dipropionate (BDP) before sleep every day for the past two years because using this collunarium seemed to mitigate the nasal obstruction and mucus during sleep. The patient did not report this fact before the endocsopy because she did not associate it with her subjective symptom. In this case, it was assumed that nebulized rhinenchysis BDP was accidentally swallowed to the pharynx and esophagus during sleep. As a treatment, rhinenchysis BDP was canceled and instead Azunol mouth washing (gargling/nasal douche) was used. No antifungal agent was used. In two weeks, the patient reported some improvement, and this was confirmed by reexamination of the upper gastrointestinal tract using endoscope in one month and a half. Pharyngitis was improved, and in the digital endoscopic assessment of esophageal candidiasis complicating inhaled steroid therapy the esophageal candidiasis became Grade I (mild grade). As for the later progress, the patient did not report any subjective symptoms such as nasal obstruction and dysphagia. In addition, the inflammation caused by candidiasis and found in the early examination was improved. The patient in this case was under treatment for thrombosis in the vein of lower extremity, but no complications such as diabetes mellitus or immune deficiency syndrome were observed. DISCUSSION: Esophageal candidiasis by chronic administration of inhalation of steroid before sleep for asthmatic patients has been reported. However, there has not been a report of esophageal candidiasis by chronic administration of rhinenchysis steroid before sleep for patients with allergic rhinitis. Similarly, in the case of the use of steroid in the form of collunarium before sleep, steroid stayed in the esophagus via the transendothelial nasal cavity, and that seemed to cause, in the long run, to develop esophageal candidiasis. CONCLUSIONS: One of the implications of the above case is that collunarium can go down, even when it is nebulized in the nasal cavity, to the esophagus via the nasal cavity to buccal capsule. This suggests the necessity for preventative measures in the case of chronic administration of steroid as follows. A. Blowing of the nose just after the use of collunarium B. Daily rinsing (gargling and nasal douche). 相似文献
103.
Makoto Fujimura Takashi Kamakura Hirokazu Inoue Isamu Yamaguchi 《Current genetics》1994,25(5):418-422
We have previously shown that increased sensitivity to diethofencarb in the carbendazim(MBC)-resistant F914 strain of Neurospora crassa is caused by a single amino-acid change in -tubulin, 198Glu to Gly. Three diethofencarb-resistant mutants that are also resistant to MBC were isolated from strain F914. They contained single base-pair-substitution mutations in the -tubulin gene. The amino acid changes in -tubulin, Phe from 250Leu, Val from 165Ala, and Ala from 237Thr, were responsible for diethofencarb-resistance in the mutant strains FR511, FR513, and FR421, respectively. The amino acid at position 198 of -tubulin in these mutants was Gly, which is the same as in strain F914. -tubulin genes with 198Glu were constructed by site-directed mutagenesis. The altered -tubulin genes derived from FR511 and FR421 transformed the wild-type strain to resistance to MBC, indicating that 250Phe and 237Ala in -tubulin are responsible for resistance not only to diethofencarb but also to MBC. 相似文献
104.
105.
Suga S Kanno T Ogawa Y Takeo T Kamimura N Wakui M 《Pflügers Archiv : European journal of physiology》2000,440(4):566-572
Using the patch-clamp method, we studied the mechanism of depolarization of rat pancreatic beta-cells induced by glucagon-like peptide 1 (7-36) amide (GLP-1). GLP-1 caused depolarization in a concentration-dependent manner (0.2-100 nM). Exendin (9-39) amide, a GLP-1 receptor antagonist, prevented the GLP-1-induced depolarization. GLP-1 reduced tolbutamide-sensitive membrane currents evoked by voltage ramps from -90 to -50 mV, recorded in the perforated whole-cell configuration, suggesting that GLP-1 decreased the activity of the ATP-sensitive K+ channel (KATP). This GLP-1 effect was prevented by exendin (9-39) amide. In cells treated with Rp-cAMPS, an inhibitor of the cAMP-dependent protein kinase (PKA), GLP-1 still caused depolarization and reduced the whole-cell membrane current through KATP. Examined in the cell-attached configuration, 20 nM GLP-1, applied out of the patch, had little effect on KATP activity. In the inside-out configuration, the open time probability and the single-channel conductance of KATP in the absence of ATP inside the membrane were unaffected by the presence of 20 nM GLP-1 in the pipette. In both conditions, application of ATP to the inside of the membrane reduced KATP activity. The half-maximal concentrations (ki) of ATP were 11.6 microM without and 5.6 microM with 20 nM GLP-1 in the pipette (P<0.05). The values of the Hill coefficient (h) were 1.03 without and 1.01 with GLP-1. We conclude that GLP-1 reduces KATP activity by elevating the sensitivity of KATP to ATP, resulting in depolarization of pancreatic beta-cells. This GLP-1 action is independent of the cAMP signalling pathway. 相似文献
106.
Atsushi Ohashi PhD Hirohisa Kotera BS Hideo Hori BS Makoto Hibiya PhD Koji Watanabe MD PhD Kazutaka Murakami MD PhD Midori Hasegawa MD PhD Makoto Tomita MD PhD Yoshinobu Hiki MD PhD Satoshi Sugiyama MD PhD 《Journal of artificial organs》2005,8(4):252-256
Polyvinyl chloride (PVC) tubing is an indispensable medical material for extracorporeal circulation therapy. However, di(2-ethylhexyl)phthalate
(DEHP), a suspected endocrine disruptor, can be eluted from PVC, suggesting that an alternative material that does not contain
DEHP is needed for clinical applications. First, we evaluated the endocrine disrupting risks of the plasticizers contained
in PVC tubes by investigating their binding affinities for the human estrogen receptor alpha (ERα). Our results revealed that,
while DEHP has some binding affinity for ERα, neither epoxidized soybean oil nor tris(2-ethylhexyl)trimellitate (an alternative
to DEHP) has any affinity for ERα. Second, we evaluated the endocrine disrupting risks of a tube made of newly developed plasticizer-free
(PF) materials. We confirmed the presence of DEHP and detected several unidentified substances in plasma stored within the
PVC tube. This plasma's competitive binding affinity for ERα was significantly higher than that of control plasma (P < 0.01). In contrast, the profile of plasma stored in the PF tube was similar to that of the control, both in terms of high-performance
liquid chromatography chromatograms and competitive binding capacity for ERα, suggesting that the PF tube is biocompatible
and is useful for reducing the elution of substances capable of binding to ERα.
Presented in part at the 42nd Congress of the Japanese Society for Artificial Organs, October 5–7, 2004, Tokyo, Japan 相似文献
107.
Toru Furukawa Rumi Fujisaki Yoshitaro Yoshida Naomi Kanai Makoto Sunamura Tadayoshi Abe Kazunori Takeda Seiki Matsuno Akira Horii 《Modern pathology》2005,18(8):1034-1042
DUSP6/MKP-3 is identified as a candidate tumor suppressor gene for pancreatic cancer. The aim of this study was to elucidate the roles of DUSP6 in the pancreatic carcinogenesis through the pancreatic intraepithelial neoplasia and/or intraductal papillary-mucinous neoplasms, both of which are considered to be precursor lesions of invasive carcinoma of the pancreas, by comparing with involvements of other major tumor suppressive pathways. Expressions of DUSP6, CDKN2A, TP53, and SMAD4 were investigated by immunohistochemistry in a total of 206 lesions of dysplastic ductal precursors and carcinomas retrieved from 52 pancreata with invasive ductal carcinomas and 51 of those with intraductal papillary-mucinous neoplasms. The intensity of staining was evaluated in lesions at different atypical grades and statistically compared among them. Mutations of KRAS2 were analyzed by methods of the allele-specific oligonucleotide hybridization and nucleotide sequencing. In pancreata with invasive ductal carcinomas, expressions of DUSP6 were abrogated exclusively in the invasive carcinoma cells in contrast to its fairly preserved expressions in pancreatic intraepithelial neoplasia. In pancreata with intraductal papillary-mucinous neoplasms, abrogated expressions of DUSP6 were observed in a relatively small fraction of intraductal adenoma/borderlines and intraductal carcinomas. Most of the intraductal adenoma/borderline lesions with abrogation of DUSP6 harbored mutations of KRAS2. None of the molecules was associated with each other in any grade of lesions. Morphological variations of papillae of the intraductal papillary-mucinous neoplasms were evaluated and analyzed for their associations with abrogations of the molecules, which resulted in finding of no significant associations. Our results suggest that the abrogation of DUSP6 is associated exclusively with progression from pancreatic intraepithelial neoplasia to the invasive ductal carcinoma while it is potentially associated with initiation of intraductal papillary-mucinous neoplasms with mutated KRAS2, which is independent of other major tumor suppressive pathways in both types of neoplasms. 相似文献
108.
109.
A protein, Vp130, that interacts with the host cell wall was isolated from Chlorovirus CVK2. From its peptide sequence, the gene for Vp130 was identified on the PBCV-1 genomic sequence as an ORF combining A140R and A145R. In Vp130, the N-terminus was somehow modified and the C-terminus was occupied by 23-26 tandem repeats of a PAPK motif. In the internal region, Vp130 contained seven repeats of 70-73 amino acids, each copy of which was separated by PAPK sequences. This protein was well conserved among NC64A viruses. A recombinant rVp130N protein formed in Escherichia coli was shown not only to bind directly to the host cell wall in vitro but also to specifically bind to the host cells, as demonstrated by fluorescence microscopy. Because externally added rVp130N competed with CVK2 to bind to host cells, Vp130 is most likely to be a host-recognizing protein on the virion. 相似文献
110.
Watanabe Y Hashimoto S Kakita A Takahashi H Ko J Mizuno M Someya T Patterson PH Nawa H 《Neuroscience research》2004,48(3):345-353
Cytokines have been implicated in the etiology or pathology of various psychiatric diseases of developmental origin such as autism and schizophrenia. Leukemia inhibitory factor (LIF) is induced by a variety of brain insults and known to have many influences on mature and immature nervous system. Here, we assessed the neurobehavioral and pathological consequences of peripheral administration of LIF in newborn rats. Subcutaneous LIF injection induced STAT3 phosphorylation in many brain regions and increased glial fibrillary acidic protein (GFAP) immunoreactivity in the neocortex, suggesting that LIF had direct effects in the central nervous system. The LIF-treated rats displayed decreased motor activity during juvenile stages, and developed abnormal prepulse inhibition in the acoustic startle test during and after adolescence. They displayed normal learning ability in active avoidance test, however. Brain neuronal structures and startle responses were grossly normal, except for the cortical astrogliosis during neonatal LIF administration. These results indicate that LIF induction in the periphery of the infant has a significant, but discrete impact on neurobehavioral development. 相似文献