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1.
K. Miura S. Yamaoka K. Arizono S. Ohba T. Koga T. Kawasaki N. Yoshida I. Asahina 《The British journal of oral & maxillofacial surgery》2019,57(6):529-535
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism. 相似文献
2.
Sami S Zoghbi H Umesha Shetty Masanori Ichise Masahiro Fujita Masao Imaizumi Jeih-San Liow Jay Shah John L Musachio Victor W Pike Robert B Innis 《Journal of nuclear medicine》2006,47(3):520-527
18F-2beta-Carbomethoxy-3beta-(4-chlorophenyl)-8-(2-fluoroethyl)nortropane (18F-FECNT), a PET radioligand for the dopamine transporter (DAT), generates a radiometabolite that enters the rat brain. The aims of this study were to characterize this radiometabolite and to determine whether a similar phenomenon occurs in human and nonhuman primate brains by examining the stability of the apparent distribution volume in DAT-rich (striatum) and DAT-poor (cerebellum) regions of the brain. METHODS: Two rats were infused with 18F-FECNT and sacrificed at 60 min. Extracts of brain and plasma were analyzed by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometric (LC-MS) techniques. Two human participants and 3 rhesus monkeys were injected with 18F-FECNT and scanned kinetically, with serial arterial blood analysis. RESULTS: At 60 min after the injection of rats, 18F-FECNT accumulated to levels about 7 times higher in the striatum than in the cortex and cerebellum. The radiometabolite was distributed at equal concentrations in all brain regions. The LC-MS techniques identified N-dealkylated FECNT as a major metabolite in the rat brain, and reverse-phase HPLC detected an equivalent amount of radiometabolite eluting with the void volume. The radiometabolite likely was 18F-fluoroacetaldehyde, the product expected from the N-dealkylation of 18F-FECNT, or its oxidation product, 18F-fluoroacetic acid. The distribution volume in the cerebellum increased up to 1.7-fold in humans between 60 and 300 min after injection and 2.0 +/- 0.1-fold (mean +/- SD; n = 3) in nonhuman primates between 60 and 240 min after injection. CONCLUSION: An 18F-fluoroalkyl metabolite of 18F-FECNT originating in the periphery confounded the measurements of DAT in the rat brain with a reference tissue model. Its uniform distribution across brain regions suggests that it has negligible affinity for DAT (i.e., it is an inactive radiometabolite). Consistent with the rodent data, the apparent distribution volume in the cerebellum of both humans and nonhuman primates showed a continual increase at late times after injection, a result that may be attributed to entry of the radiometabolite into the brain. Thus, reference tissue modeling of 18F-FECNT will be prone to more errors than analysis with a measured arterial input function. 相似文献
3.
Masanori Murakami Haruhiko Okada Masahiko Nishida Kimikazu Hamano 《Annals of thoracic and cardiovascular surgery》2006,12(3):216-218
A 14-year-old boy had a needle accidentally inserted through his chest wall. Chest X-ray showed a needle-shaped metallic density localized in the cardiac silhouette. An echocardiography indicated the needle had passed through the interventricular septum, and its eye and point had reached the right and left ventricle, respectively. Surgical removal of the needle was performed. The needle could not be observed from the heart surface, and was recognized in a dent 5 mm on the right side from the left anterior descending branch (LAD). The needle was easily removed under extracorporeal circulation, and he was discharged ten days after the operation. 相似文献
4.
In rats treat-given hydrocortisone to suppress healing, tensile strength of the skin at the site of an incision wound was significantly higher in rats locally treated with carnosine than in untreated animals. Similar effects on the tensile strength of the skin were observed by the administration of beta-alanine and histidine, but not of beta-alanine alone. Exogenous carnosine was degraded in the body by carnosinase and histidine decarboxylase to yield histamine. Since beta-alanine, the other degradation product of carnosine, was found to stimulate the biosynthesis of nucleic acids and collagen, histamine derived from carnosine is considered to have enhanced the process of wound healing by stimulating effusion at the initial stage of inflammation. Thus, the enhancement by carnosine of wound healing may be ascribed to stimulation of early effusion by histamine and of collagen biosynthesis by beta-alanine. The wound-healing effects of carnosine were further demonstrated by the observation that carnosine significantly increased granulation suppressed by cortisone, mitomycin C, 5-fluorouracil, and bleomycin. 相似文献
5.
Tetsuya Nomura Tatsuya Kawasaki Takuji Tanabe Akihiro Azuma Hiroaki Matsubara 《Annals of thoracic and cardiovascular surgery》2007,13(2):118-121
Mediastinal cystic tumors are well-marginated round lesions that comprise 12% to 18% of all mediastinal masses. These lesions include a variety of diseases with overlapping radiologic appearances and variable prognoses. Pathological examinations are almost always required for differential diagnosis. We encountered a case of anterior mediastinal tumor discovered in the process of investigation of Raynaud's phenomenon. Taking into account the tumor location, a pericardial cyst was initially suspected. However, the tumor was surgically resected and histopathological examinations demonstrated thymus-like tissue in the cyst walls. Raynaud's phenomenon greatly improved after surgery. These findings suggested that cystic thymoma originated from ectopic thymic tissue and is accompanied by paraneoplastic syndrome. 相似文献
6.
Haruhiko Nakamura Norihito Kawasaki Masahiko Taguchi Hajime Kitamura 《Annals of thoracic and cardiovascular surgery》2007,13(4):254-257
A minute small-cell lung cancer measuring 8 x 5 mm was detected and serially imaged by computed tomography for about a year preceding resection. Although this solid nodule showed a short overall doubling time (76 days), the growth curve included an early phase without apparent growth prior to the phase of rapid growth. Accordingly, lung cancer cannot be ruled out when a small nodule (<10 mm) does not enlarge in the first several months of computed tomographic follow-up. 相似文献
7.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD. 相似文献
8.
Dnyanesh N Tipre Sami S Zoghbi Jeih-San Liow Michael V Green Jurgen Seidel Masanori Ichise Robert B Innis Victor W Pike 《Journal of nuclear medicine》2006,47(2):345-353
18F-FCWAY (18F-trans-4-fluoro-N-(2-[4-(2-methoxyphenyl) piperazin-1-yl)ethyl]-N-(2-pyridyl)cyclohexanecarboxamide) is useful in clinical research with PET for measuring serotonin 1A (5-HT1A) receptor densities in brain regions of human subjects but has significant bone uptake of radioactivity due to defluorination. The uptake of radioactivity in skull compromises the accuracy of measurements of 5-HT1A receptor densities in adjacent areas of brain because of spillover of radioactivity through the partial-volume effect. Our aim was to demonstrate with a rat model that defluorination of 18F-FCWAY may be inhibited in vivo to improve its applicability to measuring brain regional 5-HT1A receptor densities. METHODS: PET of rat head after administration of 18F-FCWAY was used to confirm that the distribution of radioactivity measured in brain is dominated by binding to 5-HT1A receptors and to reveal the extent of defluorination of 18F-FCWAY in vivo as represented by radioactivity (18F-fluoride ion) uptake in skull. Cimetidine, diclofenac, and miconazole, known inhibitors of CYP450 2EI, were tested for the ability to inhibit defluorination of 18F-FCWAY in rat liver microsomes in vitro. The effects of miconazole treatment of rats on skull radioactivity uptake and, in turn, its spillover on brain 5-HT1A receptor imaging were assessed by PET with venous blood analysis. RESULTS: PET confirmed the potential of 18F-FCWAY to act as a radioligand for 5-HT1A receptors in rat brain and also revealed extensive defluorination. In rat liver microsomes in vitro, defluorination of 18F-FCWAY was almost completely inhibited by miconazole and, to a less extent, by diclofenac. In PET experiments, treatment of rats with miconazole nitrate (60 mg/kg intravenously) over the 45-min period before administration of 18F-FCWAY almost obliterated defluorination and bone uptake of radioactivity. Also, brain radioactivity almost doubled while the ratio of radioactivity in receptor-rich ventral hippocampus to that in receptor-poor cerebellum almost tripled to 14. The plasma half-life of radioligand was also extended by miconazole treatment. CONCLUSION: Miconazole treatment, by eliminating defluorination of 18F-FCWAY, results in effective imaging of brain 5-HT1A receptors in rat. 18F-FCWAY PET in miconazole-treated rats can serve as an effective platform for investigating 5-HT1A receptors in rodent models of neuropsychiatric conditions or drug action. 相似文献
9.
Hiroto Egawa Shingi Uemoto Yasutugu Takada Kazue Ozawa Satoshi Teramukai Hironori Haga Mureo Kasahara Kouhei Ogawa Hiroshi Sato Masako Ono Kenji Takai Masanori Fukushima Kayo Inaba Koichi Tanaka 《Liver transplantation》2007,13(9):1262-1271
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance. 相似文献
10.
Madoka Minoguchi Nobuyuki Yanagawa Chisato Ishikawa Junpei Sasajima Mitsuru Goto Miho Okamoto Yoshinori Saito Masanori Murakami Yutaka Orii Toru Yaosaka 《Nihon Shokakibyo Gakkai zasshi》2007,104(7):1082-1087
Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed. 相似文献