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1.
Masahiro Yamauchi Hiroko Kusano Etsuko Saito Takeshi Iwata Masashi Nakakura Yasuki Kato Takaaki Uochi Shiro Akinaga Noboru Aoki 《Journal of controlled release》2006,114(2):268-275
Previously, we demonstrated that wrapping dextran fluorescein anionic/cationic lipid complexes with neutral lipids produced a stable formulation that markedly increased the duration of the compound in plasma after intravenous administration to rats. The improved drug-delivery properties of the wrapped liposomes (WL) relative to other formulations suggested that this technology could offer important advantages for the administration of other polyanionic drugs, including antisense oligodeoxynucleotides (ODN). In the present study, we investigated the value of WL for formulating fluorescence-labeled phosphorothioated ODN (F-ODN). WL encapsulating F-ODN/cationic lipid complexes were prepared efficiently using similar methodology to that used in our earlier study. Studies confirmed that these WL were stable in vitro. Following intravenous administration to mice, free F-ODN and naked F-ODN/cationic lipid complexes were rapidly eliminated whereas administration of the WL resulted in high blood concentrations of drug that were maintained for several hours. Additional studies were conducted in mice that were inoculated with tumor cells (Caki-1 xenograft model, human kidney); in these experiments, intravenous administration of WL delivered 13 times more F-ODN to the tumor site than achieved after injection of free F-ODN. 相似文献
2.
Toru Yamaguchi Ippei Kanazawa Masahiro Yamamoto Soichi Kurioka Mika Yamauchi Shozo Yano Toshitsugu Sugimoto 《BONE》2009,44(2):174-179
The association of bone with the metabolic syndrome and its features, visceral fat accumulation or insulin resistance, remains unclear. We determined visceral and subcutaneous fat areas (V and S) by computed tomography on 187 men (28–83 years) and 125 postmenopausal women (46–82 years) with type 2 diabetes. Men whose V was 100 cm2 or more had significantly lower urinary N-terminal cross-linked telopeptide of type-I collagen (p = 0.005), higher femoral neck bone mineral density (FN-BMD) (p = 0.004), and lower prevalence of vertebral fractures (VFs) (p = 0.04) than controls. Fat mass, V, S, and lean body mass positively correlated with FN-BMD in men and with lumbar (L) and FN-BMD in women. When adjusted for weight, these correlations became negative. Urinary C-peptide positively correlated with FN-BMD in both genders. Multivariate logistic regression analysis adjusted for age, height, weight, L-BMD, duration of diabetes, and diabetes therapies identified V in men and urinary C-peptide in women as factors inversely associated with the presence of VFs [odds ratio (OR) = 0.61 per SD increase, p = 0.04, and OR = 0.32, p = 0.01, respectively]. These findings suggest that, of the components of the metabolic syndrome, body fat in gravity and hyperinsulinemia could increase FN-BMD in diabetic subjects. Visceral fat in men and hyperinsulinemia in women may protect against VFs independent of weight, L-BMD, diabetes duration, or therapies. 相似文献
3.
4.
In Vivo Molecular Imaging Characterizes Pulmonary Gene Expression During Experimental Lung Transplantation 总被引:2,自引:0,他引:2
Sekhar Dharmarajan Makio Hayama James Kozlowski Takaaki Ishiyama Mikio Okazaki Phillip Factor G. Alexander Patterson Daniel P. Schuster 《American journal of transplantation》2005,5(6):1216-1225
Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation. 相似文献
5.
Naomi Matsumoto Manabu Ikeda Ryuji Fukuhara Takayuki Hyodo Tomohisa Ishikawa Takaaki Mori Yasutaka Toyota Teruhisa Matsumoto Hiroyoshi Adachi Shunichiro Shinagawa Kazuhiko Hokoishi Hirotaka Tanabe Nobutsugu Hirono 《Brain and nerve》2006,58(9):785-790
OBJECTIVE: Neuropsychiatric disturbances are common and burdensome symptoms of dementia. Assessment and measurement of neuropsychiatric disturbances are indispensable to the management of patients with dementia. Neuropsychiatric Inventory (NPI) is a comprehensive assessment tool that evaluates psychiatric symptoms in dementia. We translated the NPI-Caregiver Distress Scale part of NPI (NPI-D) and NPI-Brief Questionnaire Form (NPI-Q) into Japanese and examined their validity and reliability. SUBJECTS AND METHODS: The subjects were 152 demented patients and the caregivers who lived with them. These patients consisted of 76 women and 76 men; their mean age was 73.9 +/- 7.8 (S.D.; range: 49 to 93) years. Their caregivers consisted of 46 men and 106 women; their mean age was 65.0 +/- 11.4 (S.D.; range: 35 to 90) years. The Mini-Mental State Examination (MMSE) was conducted with all patients and NPI-Q, NPI, NPI-D, and the Zarit caregiver burden interview (ZBI) were conducted with all caregivers. We examined validity of NPI-D by comparing its score with the MMSE and ZBI scores, and the validity of NPI-Q by comparing its score with the NPI and NPI-D scores. In order to evaluate test-retest reliability, NPI-D was re-adopted to 30 randomly selected caregivers by a different examiner one month later and NPI-Q was re-executed by 27 randomly selected caregivers one day later. RESULTS: Total NPI-D score was significantly correlated with ZBI (rs = 0.59, p < 0.01). Test-retest reliability of NPI-D was adequate (ri = 0.47, p < 0.01). Total NPI-Q severity score and distress score were strongly correlated with NPI (r = 0.77, p < 0.01) and NPI-D (r = 0.80, p < 0.01) scores, respectively. Test-retest reliability of the scores of NPI-Q was acceptably high (the severity score; ri = 0.81, p < 0.01, the distress score; ri = 0.80, p < 0.01). CONCLUSION: The Japanese version of NPI-D and NPI-Q demonstrated sufficient validity and reliability as well as the original version of them. These are useful tools for evaluating psychiatric symptoms in demented patients and their caregivers' distress attributable to these symptoms. 相似文献
6.
Resolution of homonymous visual field loss documented with functional magnetic resonance and diffusion tensor imaging. 总被引:5,自引:0,他引:5
Masaki Yoshida Masahiro Ida Thien Huong Nguyen Marie-Therese Iba-Zizen Luc Bellinger Jean Louis Stievenart Takehiko Nagao Shinsuke Kikuchi Takaaki Hara Takuya Shiba Kenji Kitahara Emmanuel Alain Cabanis 《Journal of neuro-ophthalmology》2006,26(1):11-17
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders. 相似文献
7.
Toru Ishizaka Richard G Ohye Caren S Goldberg Stephen R Ramsburg Takaaki Suzuki Eric J Devaney Edward L Bove 《European journal of cardio-thoracic surgery》2003,23(5):715-718
OBJECTIVE: Given the limited availability of small-sized cryopreserved pulmonary homografts, we implanted a series of Shelhigh No-React porcine pulmonic valve conduits (SPVC). The aim of this study was to evaluate the short-term performance following implantation. METHODS: From February 2000 to September 2000, the SPVC was implanted 25 times in 24 patients in the right ventricular outflow tract (RVOT) to correct congenital anomalies. The anatomical malformations were TOF/PA in eight patients, TGA/VSD/PS in four, truncus arteriosus in four, IAA/VSD/AS or AA in four, l-TGA/VSD in two and other in two. Age at operation was 2.8+/-3.9 years (mean+/-SD), including 12 patients under 1 year. The median conduit size was 14mm (range, 10-18). RESULTS: At a mean follow-up of 23+/-5 months, two late deaths (8%) have occurred. Although they were not primarily conduit related, both showed severe conduit stenosis. Twenty-one conduits (84%) showed mild to severe conduit stenosis, regurgitation or both. Two patients underwent balloon dilatation for distal conduit stenosis. Twelve conduits (48%) in 11 patients were removed at a median of 12 months (range, 2-18 months) due to RVOT obstruction in 11 and free conduit insufficiency with pseudoaneurysm in one. The typical findings of the explanted conduits were prominent intimal peel formation at the distal anastomosis without calcification. The actuarial freedom from reintervention at 18 months was 48+/-10%. CONCLUSIONS: Our experience of the SPVC with the diameter of 14mm or less has revealed a high incidence of distal conduit stenosis due to intimal peel formation resulting in early conduit failure. These findings have led us to abandon its use when other options are available. 相似文献
8.
T Kanno H Oka K Kim A Tamori K Ohtake H Sakaguchi N Kurioka T Kuroki Y Mizoguchi K Kobayashi 《Nihon Shokakibyo Gakkai zasshi》1992,89(1):55-60
To evaluate prognostic significance of echogenic lesion within small hepatocellular carcinoma (SHCC, less than or equal to 2 cm in diameter), clinical and pathological findings of 32 cases with SHCC containing echogenic lesion (echogenic SHCC) were compared with those of 55 cases with non-echogenic SHCC. Compared with the non-echogenic SHCC group, the frequency of clinical stage I was significantly higher, and there were significantly more cases with solitary tumor relative to cases with multiple tumors in the echogenic SHCC group. Histologically, the incidence of the HCC composed of well-differentiated tumor cells corresponding to Edmondson's grade I was significantly higher in the echogenic SHCC group than in the non-echogenic SHCC group. Although HCCs tended to become progressively less differentiated with increasing tumor sizes in the both groups, the process of cellular change appeared to proceed more slowly in the echogenic SHCC group. Survival rate after tumor detection was 73% at three years, 56% at five years and 48% at seven years and nine years in the echogenic SHCC group, while it was 46% at three years, 42% at five years and 0% at seven years in the non-echogenic SHCC group. The present results showed that the presence of echogenic lesion within SHCC could be useful prognostic indicator. 相似文献
9.
Takaaki Ohmori Ryo Tabei Norimasa Arita Mari Kondo Tetsuo Kozawa Yoshinori Chikamori Norifumi Ueda 《Pathology international》1983,33(5):999-1007
This report concerns a case of solitary extramedullary plasmacytoma of the left submandibular lymph node in a 56-year-old man. The tumor showed monoclonal proliferation of abnormal plasma cells which revealed highly positive stainings of both methylgreen pyronin and kappa light chain using the immunoperoxidase technique in the cytoplasms, and further revealed massive'.amyloid'deposits in the stroma, which suggested the possibility of sequential amyloid formation upon the secretion of paraprotein by tumor cells. 相似文献
10.