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81.
82.
Katsuaki Ito Erika Shimomura Takahiro Iwanaga Mitsuya Shiraishi Kazutoshi Shindo Junji Nakamura Hiromitsu Nagumo Minoru Seto Yasuharu Sasaki† Yoh Takuwa‡ 《The Journal of physiology》2003,546(3):823-836
Although the prostate gland is a rich source of α1-adreno- (α1-AR) and m1-cholino receptors (m1-AChR), the membrane processes associated with their activation in glandular epithelial cells is poorly understood. We used the whole-cell patch-clamp technique to show that the agonists of the respective receptors, phenylephrine (PHE) and carbachol (CCh), activate cationic membrane currents in lymph node carcinoma of the prostate (LNCaP) human prostate cancer epithelial cells, which are not dependent on the filling status of intracellular IP3 -sensitive Ca2+ stores, but directly gated by diacylglycerol (DAG), as evidenced by the ability of its membrane permeable analogue, OAG, to mimic the effects of the agonists. The underlying cationic channels are characterized by the weak field-strength Eisenman IV permeability sequence for monovalent cations ( P K (25) > P Cs (4.6) > P Li (1.4) > P Na (1.0)), and the following permeability sequence for divalent cations: P Ca (1.0) > P Mg (0.74) > P Ba (0.6) > P Sr (0.36) > P Mn (0.3). They are 4.3 times more permeable to Ca2+ than Na+ and more sensitive to the inhibitor 2-APB than SK&F 96365. RT-PCR analysis shows that DAG-gated members of the transient receptor potential (TRP) channel family, including TRPC1 and TRPC3, are present in LNCaP cells. We conclude that, in prostate cancer epithelial cells, α1-ARs and m1-AChRs are functionally coupled to Ca2+ -permeable DAG-gated cationic channels, for which TRPC1 and TRPC3 are the most likely candidates. 相似文献
83.
Akihiro Nakarna Seiichi Hirota Toshihiko Okazaki Kouichi Nagano Sunao Kawano Masatsugu Hori Yukihiko Kitamura 《Pathology international》1998,48(11):843-849
Interstitial cells of Cajal (ICC) are believed to lnitlate the basic contractile activity of the gastrointestlnal tract. Interstitial cells of Cajal express c-kit receptor tyroslne kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene . As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a mlcrotransducer, which was Inserted through a pln-hole in the anterlor wall of the stomach under anesthesla. The magnitude of bile reflux was estimated by measurlng the content of bile acids In the stomach. The c-kit messenger RNA-expressing cells were detected by in sltu hybrldlzatlon. Frequency and the maxlmum pressure of the contractlon were comparable between Ws/Ws and +/+ rats, but the duration of the contractlon was significantly shorter In Ws/Ws rats than In +/+ rats. The number of c-kit messenger RNA-expresslng ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficlency of c-kit messenger RNA-expressing ICC. 相似文献
84.
Akiko Hori Masahiro Kami Sung-Won Kim Aki Chizuka Rie Kojima Osamu Imataki Michiyo Sakiyama Tamae Hamaki Yasushi Onishi Noriko Usubuchi Yukiko Kishi Naoko Murashige Kinuko Tajima Shigesaburo Miyakoshi Yuji Heike Shigeru Masuo Shuichi Taniguchi Yoichi Takaue 《Biology of blood and marrow transplantation》2004,10(1):65-72
Little information is available on the clinical characteristics of infectious complications that occur in the early period after reduced-intensity stem cell transplantation (RIST). We retrospectively investigated the clinical features of neutropenic fever and infectious episodes within 30 days after RIST in 76 patients who had received fluoroquinolones as part of their antibacterial prophylaxis. Preparative regimens included cladribine 0.66 mg/kg or fludarabine 180 mg/m2 plus busulfan 8 mg/kg. All but 1 patient survived 30 days after transplantation, and 75 patients (99%) became neutropenic within a median duration of 9 days. Neutropenic fever was observed in 29 patients (38%), and bacterial infection was confirmed in 15 (20%) of these, including bacteremia (n = 13), bacteremia plus pneumonia (n = 1), and urinary tract infection (n = 1). The causative organisms were gram-positive (n = 9) and gram-negative organisms (n = 7), with a mortality rate of 6%. Neither viral nor fungal infection was documented. Multivariate analysis showed that the presence of neutropenia at the initiation of preparative regimens was an independent risk factor for subsequent documented bacterial infections (P =.026; 95% confidence interval, 1.25-35.1). We conclude that neutropenic fever and bacteremia remain common complications in RIST. 相似文献
85.
86.
We used a questionnaire to investigate Hymenoptera hypersensitivity in 323 forest administration workers and measured total serum IgE and venom specific IgE antibodies against yellow jackets and paper wasps. The results were as follows. 1) Most of the workers, including 69 (21.8%) hypersensitive workers, had been exposed to stings by yellow jackets or wasps. 2) The titer of RAST (p less than 0.05) and RAST positive rate (p less than 0.01) were higher in the hypersensitive workers than in the non-hypersensitive ones. 3) There was a correlation between venom specific IgE titers to yellow jackets and paper wasps (rs = 0.818). 4) The titer of venom specific IgE increases with the frequency of sting exposure, and decreased gradually with the passage of time. 5) The higher the venom specific IgE titer, the higher the total serum IgE titer. 6) The titer of venom specific IgE, total serum IgE and atopy had no relation to the severity of clinical symptoms. 相似文献
87.
Toshiaki Sato Kazutoshi Terada Junnosuke Yamauchi Takuji Okaya 《Macromolecular chemistry and physics.》1993,194(1):175-185
Poly(vinyl alcohol) (PVA) and poly(vinyl acetate) having a thiol group at one end were synthesized by free-radical polymerization of vinyl acetate in presence of thioacetic acid as a chain transfer agent followed by treating with sodium hydroxide/methanol and ammonia, respectively. It was found that block copolymers containing the PVA sequence as one constituent were obtained by the redox-initiated polymerization of some vinyl monomers, for example, acrylic acid (AA) and acrylamide (AAm), using PVA having a thiol end group as reductant and an oxidant such as potassium bromate and potassium persulfate. 相似文献
88.
89.
Yoshida E Hashimoto M Hori M Kaga M Sano H Oguchi H 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,68(1):29-35
This study investigated the effects of NaOCl on resin-tooth bonds to simulate the situations of long-term durability and caries invasion. Resin-tooth bonded specimens were produced with the use of two resin adhesives (Excite and One-Bond). Resin-tooth bonded beams (adhesive area; 0.9 mm2) were serially sectioned and the specimens were immersed in 10% NaOCl medium for 0 (control), 2, 4, and 6 h after being stored in water for 24 h. After immersion, microtensile bond tests were performed. SEM fractography was conducted to calculate each failure mode by image analysis. In addition, the adhesive interface was examined with the use of TEM. In the control specimens, enamel bond strengths had no difference between Excite (45.6 +/- 15.0) and One-Bond (56.9 +/- 12.9). On the other hand, dentin bond strengths had significant difference between Excite (80.6 +/- 21.2) and One-Bond (50.7 +/- 11.2). The bond strengths decreased with increased storage time for both systems with enamel and dentin bonds. The deteriorated mineralized dentin of beams resulted in bond-strength reduction for resin-enamel bonds. For dentin bonding, the adhesive interface was gradually dissolved from the outer to the center portion of the beam. The depletion of collagen fibrils within the demineralized dentin or hybrid layer deformation was found under SEM and TEM examinations. These morphological changes are responsible for bond strength reduction of resin-dentin bonds. 相似文献
90.
Sadao Sasaki Ikuko Nakagaki Seiki Hori Hisao Kondo 《Pflügers Archiv : European journal of physiology》1996,432(3):538-545
Changes in electrolytes of pig pancreatic acinar cells following application of gastrin-cholecystokinin (CCK) were investigated
using the technique of X-ray microanalysis of hydrated and dehydrated sections of freshly frozen pancreas. After stimulation
by CCK (10–9 M), Na and Cl increased significantly in the cytoplasm [Na, from 10 mmol/kg wet wt. (48 mmol/kg dry wt.) to 19 mmol/kg (95
mmol/kg); Cl, from 22 mmol/kg (105 mmol/kg) to 49 mmol/kg (245 mmol/kg)] as well as in the luminal interspace [Na, from 53
mmol/kg (189 mmol/kg) to 65 mmol/kg (283 mmol/kg); Cl, from 65 mmol/kg (232 mmol/kg) to 102 mmol/kg (443 mmol/kg)]. In the
secretory granules Cl increased significantly from 30 mmol/kg (86 mmol/kg) to 67 mmol/kg (203 mmol/kg). K decreased significantly
from 120 mmol/kg (571 mmol/kg) to 81 mmol/kg (405 mmol/kg) in the cytoplasm, while both increased from 38 mmol/kg (109 mmol/kg)
to 58 mmol/kg (176 mmol/kg) in the granules and from 46 mmol/kg (164 mmol/kg) to 48 mmol/kg (209 mmol/kg) in the luminal interspace.
Ca increased significantly in the cytoplasm as well as in the luminal interspace, and decreased significantly in the secretory
granules. CCK evoked Ca release from secretory granules in the secretory pole of acinar cells. The values were measured from
dehydrated sections, and agreed well with those from hydrated sections. The effect of furosemide, an inhibitor of the Na+-K+-2Cl–co-transporter, on the ion transport of acinar cell was studied. When furosemide (10–5 M) was added to the external solution, the cytoplasmic Cl and Ca concentrations decreased significantly, while there was
a little decrease in Na and K concentrations under the secretory condition. These results indicate that Na+-K+-2Cl–co-transport, and Na+, Cl–and K+ exits into the lumen are involved in the mechanism of ion secretion in pig pancreatic acinar cells.
Received: 17 January 1996 / Accepted: 12 March 1996 相似文献