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131.
Fukuda J Okamura K Ishihara K Mizumoto H Nakazawa K Ijima H Kajiwara T Funatsu K 《Cell transplantation》2005,14(10):819-827
The aim of this study was to investigate the feasibility of human hepatoblastoma cell line (Hep G2), which differentiates by spheroid formation, and treatment with sodium butyrate (SB) as a cell source for hybrid artificial liver (HAL). Hep G2 spontaneously formed spheroids in polyurethane foam (PUF) within 3 days of culture and restored weak ammonia removal activity. Treatment with SB, which is a histone deacetylase inhibitor, further increased the ammonia removal activity of Hep G2 spheroids in a concentration-dependent manner. The activation of ornithine transcarbamylase--a urea cycle enzyme--was significantly related to the upregulation of ammonia removal by spheroid formation, but scarcely contributed to the further upregulation following SB treatment. In contrast with ammonia removal, treatment with SB reduced the albumin secretion of Hep G2 spheroids in a concentration-dependent manner. In the PUF-HAL module in a circulation culture, the ammonia removal rate and albumin secretion rate (per unit volume of the module) of Hep G2 spheroids treated with 5 mM SB were almost the same as those of primary porcine hepatocyte spheroids. These results suggest that simultaneous use of spheroid formation and SB treatment in Hep G2 is beneficial in enhancing the functions of human hepatocytes with potential applications in regenerative medicine and drug screening. 相似文献
132.
In vivo PET measurements with [11C]PE2I to evaluate fetal mesencephalic transplantations to unilateral 6-OHDA-lesioned rats 总被引:2,自引:0,他引:2
Inaji M Yoshizaki T Okauchi T Maeda J Nagai Y Nariai T Ohno K Ando K Okano H Obayashi S Suhara T 《Cell transplantation》2005,14(9):655-663
Positron emission tomography (PET) is a useful tool to assess and visualize neurotransmissions in vivo. In this study, we performed repeated PET scans with [11C]PE2I, a tracer of the dopamine transporter, to evaluate the alteration of the expression of dopamine (DA) transmission component after a fetal mesencephalic transplantation. The fetal mesencephalic cells were transplanted into the striatum of unilateral 6-OHDA-lesioned rats. PET scans with [11C]PE2I were performed to evaluate the DA transporter before and 2 and 4 weeks after the transplantation. Rotation behavior tests, in vitro autoradiography, measurements of DA contents in the striatum by high-performance liquid chromatography (HPLC), and tyrosine hydroxylase (TH) immunohistological examinations were performed at the same time points and examined for their relationship to changes in the dopamine transporter. The number of ipsilateral rotations induced by methamphetamine injections decreased. DA contents in the striatum measured with HPLC significantly increased. In the PET study, the binding potential of [11C]PE2I increased at 4 weeks. The results of the in vitro autoradiography study corresponded with those of the PET study. The degrees of the change in the binding potentials correlated with those of the numbers of rotations in the behavioral study and the DA contents in the striatum. In the histological examination, TH-positive cells with axons were observed at 2 and 4 weeks after the transplantation. As the dopamine transporter exists only in the axon terminal of DA neurons, these results suggested that PET measurements of [11C]PE2I binding indicated not only survival, but maturity and functioning of the transplanted cells. Repeated PET measurements of DA transporters are a useful tool in assessing the effectiveness of neural transplantations. 相似文献
133.
Kuwahara C Imamura Y Okamura N Sakai R Ikeda T 《American journal of ophthalmology》2003,135(5):722-723
PURPOSE: To report a patient with Takayasu disease with severe proliferative retinopathy progressing to bilateral blindness. A 57-year-old Japanese woman suffering from Takayasu disease for 16 years manifested severe proliferative retinopathy in both eyes, leading to blindness due to optic atrophy. DESIGN: Interventional case report. METHODS: A 57-year-old Japanese woman suffering from Takayasu disease for 16 years underwent a comprehensive opthalmologic examination. Panretinal photocoagulation and vitrectomy were performed on both eyes. SETTINGS: Institutional practice. RESULTS: At initial examination, the patient was found to have severe proliferative retinopathy with tractional retinal detachment in both eyes. The retinal detachments were repaired by the vitrectomy, however, the patient developed bilateral blindness due to optic atrophy. CONCLUSIONS: Patients with a long history of Takayasu disease can demonstrate severe proliferative retinopathy that may be resistant to photocoagulation and/or vitreous surgery. Ocular ischemia can lead to blindness from ischemic optic neuropathy. 相似文献
134.
Rapid shrinkage of remnant central neurocytoma after gamma knife radiosurgery: a case report 总被引:3,自引:0,他引:3
Hara M Aoyagi M Yamamoto M Maehara T Takada Y Nojiri T Ohno K 《Journal of neuro-oncology》2003,62(3):269-273
Central neurocytomas are typically benign tumors that have high local control rates after gross total resection. Radiotherapy for residual or recurrent central neurocytomas is controversial.We report a 30-year-old male with a central neurocytoma in the lateral ventricle. The tumor was subtotally resected through a transcallosal approach, and subsequently treated with gamma knife radiosurgery. The tumor had shrunken markedly by 2 months after radiosurgery and remained unchanged during the one year follow-up period.Gamma knife radiosurgery may be an option for effective treatment of patients with residual or recurrent central neurocytomas. 相似文献
135.
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137.
Hosono M Machida K Honda N Takahashi T Kashimada A Murata O Osada H Ohtawa N Itoyama S 《Clinical nuclear medicine》2003,28(1):25-28
The authors examined three patients with pure primary mediastinal seminomas, all of whom had marked Ga-67 uptake on scintigraphy. The unusual presentation of sclerotic bone metastases with remarkable extraosseous soft tissue involvement was observed in one patient. Another had a seminoma associated with a multiloculated thymic cyst, which is a rare lesion. 相似文献
138.
Restoration of anterior cruciate ligament-hamstring reflex arc after anterior cruciate ligament reconstruction 总被引:4,自引:1,他引:3
Eiichi?TsudaEmail author Yasuyuki?Ishibashi Yoshihisa?Okamura Satoshi?Toh 《Knee surgery, sports traumatology, arthroscopy》2003,11(2):63-67
It has recently been emphasized that restoration of neuromuscular function contributes to dynamic stability of the anterior cruciate ligament (ACL) reconstructed knee. The existence of an ACL-hamstring reflex arc, one of the protective ligament-muscular pathways, has been revealed in normal human knees. Although reinnervation to the reconstructed ACL has been observed histologically, it remains unclear whether the ACL-hamstring reflex arc is reestablished. This study examined the existence of the ACL-hamstring reflex arc in ACL-reconstructed knees by analyzing the changes in the hamstring EMG elicited by electrical stimulation to the reconstructed ACL. The patellar tendon grafts transplanted as an ACL substitute in three patients were electrically stimulated via a bipolar wire electrode inserted arthroscopically. The surface EMG was monitored from the ipsilateral biceps femoris and semitendinosus. In two of the three patients the significantly increased EMG value of the biceps femoris was detected between 120 and 140 ms after the onset of electrical ACL stimulation. The increased EMG activity detected in the biceps femoris after the stimulation to the patellar tendon graft indicated reestablishment of the ACL-hamstring reflex arc in the ACL-reconstructed knee. 相似文献
139.
Iitaka K Nakamura S Moriya S Motoyama O Sakai T 《Pediatric nephrology (Berlin, Germany)》2003,18(10):1000-1004
Eight patients with focal segmental membranoproliferative glomerulonephritis (FSMPGN) were followed for 5–16 years. Their urinary abnormalities were detected by school urinary screening in seven, and one patient presented with nephrotic syndrome. All but one patient were treated with alternate-day (ALD) prednisolone. With time, urinalysis became normal in six and two continued to have proteinuria with or without hematuria. Serum albumin, cholesterol, and creatinine levels were normal at the last follow-up. Serum C3 returned to normal levels in six, but remained persistently decreased in two. Mesangial proliferation and matrix changes in glomeruli without MPGN lesions were mild. Subendothelial and mesangial electron-dense deposits and deposits containing C3 along capillary walls and mesangium were observed. MPGN lesions and mesangial proliferation improved. No severe growth retardation was observed, but the duration and dosage of ALD prednisolone could be reduced further, since the patients with FSMPGN seemed to have an excellent prognosis. 相似文献
140.
Clinical features of 33 patients with squamous cell carcinoma of the posterior oropharyngeal wall treated at the Department of Otolaryngology, Head and Neck Surgery, Kurume University Hospital from 1973 to 2003 were analysed. Of these, 23 (21 men and 2 women, mean age: 66 years) underwent radical treatment, and 10 (8 men and 2 women, mean age: 78 years) did not. In those treated radically, 2 were stage I, 5 stage II, 6 stage III, and 10 stage IV. The primary disease was surgically treated in 16, and reconstruction added in 5, using the free jejunum in 4 and a forearm flap. Radical radiotherapy was done in 7. Five-year local control in the 23 was 35.3%. Disease-specific 5-year survival was 32.0%. Seven died of primary oropharyngeal cancer. After treatment, 78.3% were able to eat orally. In conclusion, squamous cell carcinoma of the posterior oropharyngeal wall is relatively rare and has a poorer prognosis than other types of oropharyngeal cancer. 相似文献