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81.
Zhang J Lu Y Dai J Yao Z Kitazawa R Kitazawa S Zhao X Hall DE Pienta KJ Keller ET 《The Prostate》2004,59(4):360-369
BACKGROUND: Current animal models of prostate cancer (CaP) bone metastasis do not allow measurement of either tumor growth in bone over time or activation of gene promoters in intraosseous tumors. To develop these methods, we used bioluminescent imaging (BLI) to determine if expression of receptor activator of NF-kappaB ligand (RANKL), a pro-osteoclastogenic factor that promotes CaP bone metastases, is modulated by the bone matrix protein transforming growth factor-beta (TGF-beta) in vivo. METHODS: C4-2B human CaP cells were treated with TGF-beta in vitro and RANKL mRNA and protein production were measured by polymerase chain reaction (PCR) and ELISA, respectively. Then C4-2B cells stably transfected with the RANKL promoter driving luciferase (lux) were injected intra-tibially into severe combined immundeficient (SCID) mice. Tumors were subjected to BLI every 2 weeks for 6 weeks and serum prostate specific antigen (PSA) was measured using ELISA. Vehicle (V), 1,25 dihydroxyvitamin D (VitD), or TGF-beta was administered to mice with established tumors and BLI to measure RANKL promoter activity was performed. Tumors were then subjected to immunohistochemistry for lux and assayed for RANKL mRNA levels. RESULTS: TGF-beta induced RANKL protein and mRNA expression and activated the RANKL promoter activity in a dose-dependent manner in vitro. BLI demonstrated an increase in intraosseous tumor size over time, which correlated with serum PSA levels. Administration of TGF-beta and VitD to mice with established intraosseous tumors increased lux activity compared to V. Intratibial tumor RANKL mRNA expression paralleled the increased promoter activity. Immunohistochemistry confirmed the presence of lux in the intraosseous tumors. CONCLUSIONS: These results demonstrate the ability to measure intraosseous tumor growth over time and gene promoter activation in an established intraosseous tumor in vivo and also demonstrate that TGF-beta induces activates the RANKL promoter. These results provide a novel method to explore the biology of CaP bone metastases. 相似文献
82.
83.
Kitazawa K Matsumoto M Senda M Honda A Morimoto N Kawashiro N Imashuku S 《Pediatric blood & cancer》2004,43(1):85-87
We report a case of a girl with Langerhans cell histiocytosis (LCH) of multifocal bone disease, who developed recurrent bacterial meningitis and unilateral sensorineural hearing loss during the relapsing course of the disease. Mondini dysplasia, a congenital inner ear anomaly, was suspected by high resolution computed tomographic scan and the dysplasia with cerebrospinal fluid leakage was confirmed by surgery in the ipsilateral ear showing hearing loss. Although rare, congenital inner ear anomalies such as Mondini dysplasia should be kept in mind in pediatric patients with hearing impairment and/or recurrent bacterial meningitis during chemotherapy for various types of neoplasms including LCH. 相似文献
84.
85.
Kitazawa S 《Neuroscience research》2002,43(4):289-294
Voluntary goal-directed movements, such as arm reaching, are nearly optimized in terms of smoothness over the entire movement. Such smoothness is lost with cerebellar dysfunction, suggesting the essential role of the cerebellum in optimizing movement. However, it is still not clear how the cerebellum contributes to achieving smoothness over an entire movement. A recent study has shown that such smoothness of movement can be achieved by reducing the variance of errors at the end of the movement. Here, I hypothesize that the terminal errors conveyed by climbing fibers in the cerebellum serve to reduce not only the mean error, but also the variance of the error, through a process analogous to the random walk through movement control candidates. In the random walk, the direction of each step is randomly determined, but the size of each step is determined by the error at the end of each trial. 相似文献
86.
Studies of Magnesium in Congenital Long QT Syndrome 总被引:2,自引:0,他引:2
We studied the role of magnesium (Mg) in congenital long QT syndrome (LQTS). Twenty-two congenital LQTS patients and 30 control subjects were included in this study. We measured serum Mg (SMg) level and Mg retention (MgR) level, and evaluated the role of Mg (a high MgR level reflects Mg deficiency in the body). The influence of intravenous Mg infusion on Mg level was evaluated. Relatively low SMg level and high MgR level (LQTS:control = 53:33%, p < 0.01) were recognized in congenital LQTS patients, but there was an overlap with controls. Mg supplementation did not shorten QT interval and there was no significant correlation between Mg levels and QTc interval. Patients with syncopal history showed a higher MgR level (syncope (+):syncope (-) = 70:46%, p < 0.01) and intravenous Mg infusion improved Mg deficiency. These results suggest that some (not all) congenital LQTS patients are in a Mg-deficient state, which may be associated with syncope, and Mg supplementation may prevent recurrent syncope in these patients. Because there are several subtypes of congenital LQTS, perhaps with genetic testing Mg deficiency may be identified as a significant cofactor in some forms, whereas in other forms it is not relevant. 相似文献
87.
BACKGROUND: En bloc removal of soft tumors within the brain parenchyma has rarely been performed. We describe a safe technique for en bloc removal of the tumors using a spoon retractor, which enables retraction while holding the soft mass upward. METHODS: Dissection of a tumor mass is performed under traction of the surrounding brain tissue by retracting the mass using a spoon retractor. A dissection plane is first established in a relatively safe area, not opposite the critical area, after a corticotomy. The dissection plane is then extended toward the critical side. After circumferential dissection of the tumor mass, the dissection is continued spirally into deeper regions by retracting and holding the mass upward using a spoon retractor. In this way, the tumor is removed en bloc. CONCLUSIONS: The traction-dissection method using spoon retractors is useful in performing en bloc removal of soft tumors within the brain parenchyma less invasively and provides an appropriate operating field even at depth, reducing intraoperative bleeding, and in vascular rich tumors, possibly preventing tumor seeding in cases of malignant tumors. 相似文献
88.
Early clinical results of laser epithelial keratomileusis 总被引:4,自引:0,他引:4
PURPOSE: To evaluate the efficacy of laser epithelial keratomileusis (LASEK). SUBJECTS AND METHOD: LASEK was performed on 82 eyes of 42 patients whose spherical refraction ranged from -0.75 to -12.00 D (mean, -6.09 D) and cylindrical refraction ranged from 0 to -5.00 D (mean, -0.95 D). LASEK is a method of making a epithelial flap using 20% ethanol and repositioning the flap after excimer laser ablation. The clinical results of postoperative refraction and complications were examined. RESULTS: At 1 week and 1 month after the operation, 69 eyes(84.1%) and 79 eyes(96.3%) achieved an uncorrected visual acuity of 20/20 or better. At 1 week and 1, 3 months after the operation, the mean spherical refraction was +0.09 +/- 0.49(mean +/- standard deviation) D, +0.29 +/- 0.47 D, +0.13 +/- 0.46 D. At 1 month 65 eyes (79.3%) were within +/- 0.5 D and 78 eyes(95.1%) were within +/- 1.0 D. 51 eyes (62.2%) had the complication of corneal haze. CONCLUSION: LASEK achieved good uncorrected visual acuity, but there were some complications such as postoperative pain, the delayed recovery of visual acuity, and corneal haze, so that a long and careful follow-up seems necessary. 相似文献
89.
Design and synthesis of the potent,orally available,brain-penetrable arylpyrazole class of neuropeptide Y5 receptor antagonists 总被引:1,自引:0,他引:1
Sato N Takahashi T Shibata T Haga Y Sakuraba A Hirose M Sato M Nonoshita K Koike Y Kitazawa H Fujino N Ishii Y Ishihara A Kanatani A Fukami T 《Journal of medicinal chemistry》2003,46(5):666-669
Novel arylpyrazole derivatives were synthesized and evaluated as neuropeptide Y (NPY) Y5 receptor antagonists. Compound (-)-7, which features a novel chiral 2,3-dihydro-1H-cyclopenta[a]naphthalene moiety, showed good binding affinity and antagonistic activity for the Y5 receptor. After intracerebroventricular administration in SD rats, (-)-7 significantly inhibited food intake that was induced by the centrally administered Y5-preferring agonist, bovine pancreatic polypeptide, but had only a negligible effect on NPY-induced feeding. 相似文献
90.
To determine the pregnancy-associated changes in the porcine uterine contractility, the spontaneous contraction and the mechanical responses to bioactive substances of uteri in nonpregnant proestrus and pregnant pigs (25-60 days of gestation) were compared in vitro. Longitudinal muscle (LM) and circular muscle (CM) of the uterus exhibited spontaneous contraction, but the frequency in pregnant pigs was lower than that in the nonpregnant pigs. The duration and force of spontaneous contraction in the pregnant pigs were long and large compared with both in the nonpregnant pigs. L-Nitroarginine methylester (L-NAME) and 2a-[4-(4-phenyl-1,2,3,6-tetrahydropyridyl)butyl]-2a,3,4,5-tetrahydro-benzo[cd]indol-2(1H)-one (DR4004) did not change the spontaneous contraction in the uteri of nonpregnant pigs but increased its amplitude in the uteri of pregnant pigs. Isoprenaline inhibited the uterine spontaneous contraction of the nonpregnant and pregnant pigs, and the inhibition was stronger in the pregnant than in the nonpregnant pigs. 5-Hydroxytryptamine also caused inhibition of spontaneous contraction in the uteri of nonpregnant pigs (CM>LM). In the pregnant pigs, sensitivity to 5-hydroxytryptamine increased in a muscle layer-dependent manner (LM>CM) and difference in the responsiveness between LM and CM decreased. Acetylcholine contracted the uterine LM and CM strips of the pregnant and nonpregnant pigs. The responsiveness of CM increased slightly during pregnancy, but that of the LM did not change. 5-Bromo-N-(2-imidazolin-2-yl)-6-quinoxalinamine (UK14304) caused contraction of only LM in the uteri of nonpregnant pigs, but contracted both LM and CM strips in the pregnant pigs. Oxytocin and prostaglandin F(2 alpha) also contracted the uteri of nonpregnant pigs (LM>CM). Pregnancy increased the contraction of both agents in the LM and CM, but the increment was marked in the CM. The contractile forces induced by all stimulants were increased (by 1.7- to 2.5-fold) in the LM and CM of pregnant pigs. In conclusion, (1) low frequency, slow kinetics and large force of spontaneous contraction are characteristics of the pregnant porcine uteri, and nitric oxide and 5-hydroxytryptamine are supposed to be partially involved in the regulation of spontaneous contraction, and (2) responses to both contractile and inhibitory agents are increased in the pregnant pigs. Increment of the responsiveness is conspicuous in the muscle layer that is less sensitive to each agonist in the uteri of nonpregnant pigs. According to the pregnancy-associated changes, muscle layer-related differences of responsiveness to bioactive substances in the nonpregnant pigs tend to decrease in the pregnant pigs. 相似文献