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51.
Aim: This study aims to establish a pressure ulcers model that visualizes the microcirculation, and to examine the participation of ischemia‐reperfusion injury in the pathophysiology of pressure ulcers.
Methods: An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions: The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
Methods: An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions: The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
52.
Takafumi Nagaoka Yoichi Katayama Toshikazu Kano Kazutaka Kobayashi Hideki Oshima Chikashi Fukaya Takamitsu Yamamoto 《Neuromodulation》2007,10(3):206-215
Objective. Employing [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess the correlation between the effect of deep brain stimulation (DBS) on the subthalamic nucleus (STN) and the regional cerebral metabolic rate of glucose (rCMRGlc) in advanced Parkinson's disease patients (N = 8). Materials and Methods. On the basis of patients’ diary records, we performed FDG‐PET during the off‐period of motor activity with on‐ or off‐stimulation by STN‐DBS on separate days and analyzed the correlation between changes in motor symptoms and alterations in the rCMRGlc. Result. When FDG‐PET was performed, the motor score on the unified Parkinson's disease rating scale (UPDRS) was 64% lower with on‐stimulation than with off‐stimulation (p < 0.001, Wilcoxon single‐rank test). STN‐DBS increased the rCMRGlc in the posterior part of the right middle frontal gyrus, which corresponded to the premotor area, and the right anterior lobe of the cerebellum (p < 0.005, paired t‐test). No region exhibited a decrease in rCMRGlc. Among the items of the UPDRS motor score, the changes in resting tremor and rigidity of the left extremities showed a significant correlation with the changes in rCMRGlc observed in the right premotor area (p < 0.02 and p < 0.05, respectively, Spearman's rank correlation). Conclusions. STN‐DBS either activates the premotor area or normalizes the deactivation of the premotor area. These FDG‐PET findings obtained are consistent with the idea that STN‐DBS modifies the activities of neural circuits involved in motor control. 相似文献
53.
Increased accumulation of iodine-123-IMP in the pulmonary inflammatory lesion surrounding a lung cancer 总被引:1,自引:0,他引:1
Masayuki Nakajo Noriaki Uchiyama Yoshiyuki Hiraki Yoshihiko Miyata Atsuhisa Iriki Yasunobu Hirotsu Joeji Wakimoto Yoshimasa Norimatsu 《Annals of nuclear medicine》1988,2(1):49-53
In a patient with primary lung cancer, increased accumulation of I-123-IMP was observed in a pulmonary inflammatory lesion surrounding a lung cancer which was delineated as a photon deficient area. Ga-67-citrate uptake was observed in both the inflammatory and cancerous areas. These findings suggest that I-123-IMP may have the potential to accumulate differently in a variety of pathological conditions of the lung and thus may be a clinically useful lung imaging agent. 相似文献
54.
S Sumi K Kihara Y Kageyama Y Higashi I Fukui H Oshima 《Hinyokika kiyo. Acta urologica Japonica》1990,36(8):903-6; Discussion 906-7
Normal epithelial and carcinoma cells of human bladder were investigated for the cytokeratin which is one of the intermediate filaments and comprises cytoskeleton using the immunofluorescence method. Carcinoma cell lines used were JTC-30, JTC-32, HUB-41 and T-24. In normal urothelium, keratin fibers were fine and straight with unchanged diameter and distributed regularly in the cytoplasm. By contrast, keratin fibers in bladder carcinoma cells were kinked and changed in diameter and were distributed irregularly in the cytoplasm. The above findings were most obvious in T-24 which formed undifferentiated carcinoma when transplanted to nude mice, and keratin fibers were dominantly located in the perinuclear area. The changes of keratin fibers appeared to be parallel to the grade of histological anaplasia of the tumor formed by implantation of bladder carcinoma cell line cells to nude mice. These observations suggest that the morphology of cytokeratin is a useful indicator for evaluating the grade of malignancy in transitional cell carcinoma. 相似文献
55.
High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel 总被引:2,自引:0,他引:2
Kazuyoshi Takeshita Haruaki Ishibashi Masayuki Suzuki Takumi Yamamoto Toshihiro Akaike Masashi Kodama 《Artificial organs》1995,19(2):191-193
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit. 相似文献
56.
The integrity of the sensory nervous system in the anal canals of chronically constipated children was investigated using
evoked potential techniques examining cerebral and spinal evoked potentials from the lower extremities and anal canal. Stimulation
of the posterior tibial nerve produced no significant difference in the parameters of spinal and cerebral evoked potentials
between 18 controls and 12 chronically constipated chidren. However, stimulation of the anal canal resulted in evoked potentials
related to the age and/or consciousness level of the control children. Reproducible cerebral responses were obtained only
from nine of these control children, all aged over 4 years, who were examined while awake without sedatives. A typical response
was characterized by a polyphasic wave occurring with an onset latency of 79.4± 27.7ms (mean ±SD). In the 12 chronically constipated
children, the 5 sedated patients examined while asleep did not show any reproducible potential, as in the controls. However,
in the remaining 7 children examined while awake, the occurrence of the anal canal evoked potential was significantly reduced,
and only two exhibited a cerebral response. These findings suggest that rectal mucosal perception of the intraluminal stimuli
might be disturbed in some children with chronic constipation. 相似文献
57.
Yasuna Kobayashi Ryoko Sakai Naomi Ohshiro Masayuki Ohbayashi Noriko Kohyama Toshinori Yamamoto 《Drug metabolism and disposition》2005,33(5):619-622
Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver. 相似文献
58.
Minoru Hasegawa Maki Goto Itsuki Oshima Shizufumi Ebihara 《Neuroscience and biobehavioral reviews》1995,18(4):537-540
Circadian rhythms of pineal melatonin release were measured in free-moving pigeons, Japanese quails, and chickens under light-dark cycles followed by constant dim light. Although melatonin levels differed among individual birds, circadian rhythms of melatonin were observed in all of them. Using this technique, we could examine phase shifts of melatonin rhythms and suppression of melatonin release by photic stimulation in pigeons. We could also examine effects of norepinephrine infusion on melatonin release. These results indicate that microdialysis is useful for the study of pineal melatonin rhythms in birds. 相似文献
59.
Dendritic Cells Coinjected with Tumor Cells Treated with an Anticancer Drug to Induce Tumor Rejection 总被引:1,自引:0,他引:1
Naoya Inoue Seiji Yamasaki Kan Kondo Takatsugu Kan Katsuyoshi Furumoto Masayuki Imamura 《Surgery today》2003,33(4):269-276
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug
was added.
Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally
(i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of
CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally.
Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC
alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26
cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher
level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was
followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed.
Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through
the acquisition of tumor-associated antigens from apoptotic tumor cells.
Received: January 7, 2002 / Accepted: September 3, 2002
Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry
of Education, Culture, Sports, Science and Technology (No. 11671160).
Reprint requests to: S. Yamasaki 相似文献
60.
Songji Zhao Yuji Kuge Takafumi Mochizuki Toshiyuki Takahashi Kunihiro Nakada Masayuki Sato Toshiki Takei Nagara Tamaki 《Journal of nuclear medicine》2005,46(4):675-682
The biologic mechanisms involved in the intratumoral heterogeneous distribution of 18F-FDG have not been fully investigated. To clarify factors inducing heterogeneous 18F-FDG distribution, we determined the intratumoral distribution of 18F-FDG by autoradiography (ARG) and compared it with the regional expression levels of glucose transporters Glut-1 and Glut-3 and hexokinase-II (HK-II) in a rat model of malignant tumor. METHODS: Rats were inoculated with allogenic hepatoma cells (KDH-8) into the left calf muscle (n = 7). Tumor tissues were excised 1 h after the intravenous injection of 18F-FDG and sectioned to obtain 2 adjacent slices for ARG and histochemical studies. The regions of interest (ROIs) were placed on ARG images to cover mainly the central (CT) and peripheral (PT) regions of viable tumor tissues and necrotic/apoptotic (NA) regions. The radioactivity in each ROI was analyzed quantitatively using a computerized imaging analysis system. The expression levels of Glut-1, Glut-3, and HK-II were determined by immunostaining and semiquantitative evaluation. The hypoxia-inducible factor 1 (HIF-1) was also immunostained. RESULTS: ARG images showed that intratumoral 18F-FDG distribution was heterogeneous. The accumulation of 18F-FDG in the CT region was the highest, which was 1.6 and 2.3 times higher than those in the PT and NA regions, respectively (P < 0.001). The expression levels of Glut-1, Glut-3, and HK-II were markedly higher in the CT region (P < 0.001) compared with those in the PT region. The intratumoral distribution of 18F-FDG significantly correlated with the expression levels of Glut-1, Glut-3, and HK-II (r = 0.923, P < 0.001 for Glut-1; r = 0.829, P < 0.001 for Glut-3; and r = 0.764, P < 0.01 for HK-II). The positive staining of HIF-1 was observed in the CT region. CONCLUSION: These results demonstrate that intratumoral 18F-FDG distribution corresponds well to the expression levels of Glut-1, Glut-3, and HK-II. The elevated expression levels of Glut-1, Glut-3, and HK-II, induced by hypoxia (HIF-1), may be contributing factors to the higher 18F-FDG accumulation in the CT region. 相似文献