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101.
A novel method of cryopreservation of rat and human hepatocytes by using encapsulation technique and possible use for cell transplantation 总被引:1,自引:0,他引:1
Aoki T Koizumi T Kobayashi Y Yasuda D Izumida Y Jin Z Nishino N Shimizu Y Kato H Murai N Niiya T Enami Y Mitamura K Yamamoto T Kusano M 《Cell transplantation》2005,14(9):609-620
Encapsulated hepatocyte transplantation is a promising approach to cell transplantation without immunosuppression as an alternative to whole organ liver transplantation. However, the shortage of donor cells for hepatocyte transplantation has not been resolved, and at this critical point, it seems necessary to establish a method of hepatocyte cryopreservation to allow clinical application of hepatocyte transplantation and the development of a bioartificial liver system in the near future. In this study we demonstrated that cryopreserved microencapsulated rat and human hepatocytes can retain their hepatic function and that cryopreserved microencapsulated human hepatocytes transplanted into rat spleen remain viable without immunosuppression. Rat and human hepatocytes were isolated by a collagenase digestion method, and they were microencapsulated with poly-L-lysine. The microencapsulated rat hepatocytes were transferred to culture medium (DMEM containing 10% FBS and 10% DMSO) and immediately frozen in liquid nitrogen. A warm water bath (37 degrees C) was used to thaw the microencapsulated hepatocytes. Hepatic function, drug metabolism, and cell morphology were assessed after 90 days of cryopreservation. After 1 week of cryopreservation, microencapsulated hepatocytes were cultured for up to 2 weeks to assess their hepatic function and morphology. The morphology of human hepatocytes was assessed after 30 days of cryopreservation. Cryopreserved human hepatocytes were transplanted into rat spleen to assess their morphology. Cryopreserved microencapsulated hepatocytes retained their viability and were strongly positive for expression of albumin, OAT2, CYP3A2, and CYP3A9. Two weeks after cultivation, the cryopreserved microencapsulated rat hepatocytes had retained their hepatic function (urea synthesis). Cryopreserved microencapsulated human hepatocytes also mainly survived and retained their hepatic function for at least 30 days after cryopreservation. Moreover, entrapped cryopreserved human hepatocytes also survived and expressed albumin in rat spleen after transplantation. We demonstrated a novel method of long-term cryopreservation of rat and human hepatocytes by using an encapsulation technique, with retention of biological activity and excellent survival of the cryopreserved microencapsulated human hepatocytes transplanted into rat spleen. We believe that this novel approach to hepatocytes cryopreservation provides a new direction in encapsulated cell therapy with the goal of clinical application in the near future. 相似文献
102.
CONCLUSION: CD14/-159 plays a role in sensitization to Dermatophagoides pteronyssinus in Japanese patients with allergic rhinitis. OBJECTIVE: An association between a polymorphism in the 5'-flanking region of the CD14 gene and atopic phenotypes has been identified in a pediatric American population and an adult Dutch population. The aim of this study was to determine whether the CD14/-159 polymorphism is associated with specific IgE levels in allergic rhinitis patients in a Japanese population. MATERIAL AND METHODS: The CD14/-159 genotypes of 81 unrelated patients with allergic rhinitis and 78 healthy subjects were determined and compared. The total IgE level and the specific IgE levels for three aeroallergens were determined. The IgE levels for each genotype were compared. RESULTS: The frequencies of CD14/-159 genotypes did not differ between the two groups. Among the allergic rhinitis patients, TT homozygotes had significantly fewer positive CAP-radioallergosorbent tests (CAP-RASTs) than CC homozygotes and CT heterozygotes, suggesting that the C allele is dominant. TT homozygotes also had significantly lower CAP-RAST scores for Dermatophagoides pteronyssinus, but not for Cryptomeria japonica or Dactylis glomerata, than CC homozygotes and CT heterozygotes. There was no significant association between total serum IgE levels and CD14/-159 genotypes in the allergic rhinitis patients. 相似文献
103.
104.
Hara M Kume M Oshima H Shibamoto Y Iida A Mori Y Nakamura A Murase T 《Journal of thoracic imaging》2005,20(2):118-119
In the case presented here, FDG-PET was performed to evaluate the possibility of malignancy. High FDG accumulation, with a standardized uptake ratio (SUR) of 3.0, was noted in an upper nodular compartment of the mass that exhibited malignant features histopathologically. It was suggested that FDG-PET is helpful to know which parts of lesions are benign or malignant in patients with LFTP whose prognoses are usually difficult to predict. 相似文献
105.
False-positive and true-negative hilar and mediastinal lymph nodes on FDG-PET —Radiological-pathological correlation— 总被引:3,自引:0,他引:3
Shiraki N Hara M Ogino H Shibamoto Y Iida A Tamaki T Murase T Eimoto T 《Annals of nuclear medicine》2004,18(1):23-28
OBJECTIVE: To compare histological findings of FDG-PET false-positive and true-negative hilar and mediastinal lymph nodes. METHODS: Sixty-seven lymphnode areas in 11 patients who were diagnosed to have N3 lymph nodes by FDG-PET and underwent surgery were histologically examined, and the histopathological findings in false-positive and true-negative lymph nodes were compared. Lymph nodes with higher accumulation of FDG than the surrounding mediastinum level were judged as positive. On histological sections, proportions of macrophages and lymphocytes, amount of coal dust deposit, presence of silicotic nodules, long- and short-axes of the largest node, and volume of macrophages and lymphocytes were evaluated. Correlations between the above-mentioned factors and FDG accumulation were evaluated. RESULTS: FDG uptake was not correlated with the proportion of macrophages and lymphocytes, coal dust amounts, or the presence of silicotic nodules. The long- and short-axes of the largest node in the false-positive areas were significantly longer than those in the true-negative areas (p = 0.01, and 0.001, respectively). Volumes of lymph nodes (mean +/- SD: 150 +/- 190 mm3) and macrophages (78 +/- 71 mm3) in false-positive areas were markedly larger than those in true-negative areas (68 +/- 87 mm3, p = 0.0009 and 34 +/- 54 mm3, p = 0.0001, respectively). The volume of lymphocytes was also larger in false-positive areas but less markedly. CONCLUSION: Our study suggested that false-positive results of FDG-PET in hilar and mediastinal lymph nodes were closely related to the size of lymph node and the volume of macrophages. 相似文献
106.
Yamazawa R Mizuno M Nemoto T Miura Y Murakami M Kashima H 《Psychiatry and clinical neurosciences》2004,58(1):76-81
The aim of the present study was to examine the duration of untreated psychosis (DUP) in first-episode schizophrenia patients in Japan and to investigate the available pathways to psychiatric services. Eighty-three patients who visited Keio University Hospital (n = 54) or Oizumi Mental Hospital (n = 29) were evaluated retrospectively with regard to their DUP, living situation, social participation level, referral pathway, reason for seeking treatment, and their global assessment of functioning (GAF) score. The mean DUP was 13.7 months (median, 5.0 months) overall. No significant difference in DUP was found between subjects living alone and those living with others; however, employed patients had a significantly shorter DUP (8.1 months) than unemployed patients (18.7 months). Pathways to psychiatric services were totally different between the two institutions. Fifty-two subjects (62.7%) came to the services directly: 40 patients (74.1%) came to the university hospital and 12 patients (41.4%) came to the mental hospital. At the mental hospital, nine patients (31.0%) had been admitted because of a legal obligation, and six (20.7%) had been referred through public health centers. None of the patients had been referred to either of the services by general practitioners. The main reason for seeking treatment was psychiatric symptom aggravation (59.3%) at the university hospital and acting out (64.3%) at the mental hospital. Some universal psychosocial factors appear to influence the DUP but the characteristics of specific psychiatric services may also affect treatment delays. 相似文献
107.
Sadakane K Ichinose T Takano H Yanagisawa R Sagai M Yoshikawa T Shibamoto T 《International archives of allergy and immunology》2002,128(3):220-228
BACKGROUND: Differences in allergic airway inflammation induced by ovalbumin (OVA) + diesel exhaust particles (DEP) in various murine strains have already been reported. However, there is no report that different murine strains respond differently towards house dust mites or DEP, which are known to aggravate allergic asthma. METHODS: The Dermatophagoides farinae allergens Der f (1 microg) or Der f (1 microg) + DEP (50 microg) were administered intratracheally to two different mouse strains (CBA/JN and C57BL/6N). Histological changes in the lung tissues, asthma-relevant cytokines in the lungs, and allergen-specific immunoglobulins in plasma were investigated. RESULTS: Der f treatment led to the proliferation of goblet cells, production of mucus plugs, and the recruitment of eosinophils and lymphocytes to the airways of the mice. The manifestation of the airway inflammation in the C57BL/6N mouse was much greater than in the CBA/JN mouse. The protein levels of interleukin (IL)-4 and IL-5, regulated on activation, normal T cell expressed, and presumably secreted (RANTES), and eotaxin in the lung tissue of C57BL/6N mice were higher than those in CBA/JN mice by a factor of 1.26 (IL-4), 5.26 (IL-5), 2.07 (RANTES) and 3.27 (eotaxin). DEP aggravated the manifestations of the eosinophilic inflammation in CBA/JN mice through goblet cell proliferation. However, the exact effect of DEP could not be evaluated in C57BL/6N because of its severe enhancement of the inflammation. DEP enhanced the local expression of IL-5, RANTES, and eotaxin in the CBA/JN mouse, and consequently triggered an increased IgG1 production in both strains. Allergen-specific IgE antibodies were lower than 1 titer in both mice. CONCLUSION: The murine strain differences in the pathogenesis of allergic airway disease caused by mite allergen might be related to the local expression of the cytokines we screened. The aggravating effect of DEP may be mediated by an increase in the local expression of IL-5, RANTES, eotaxin, and the production of an antigen specific to IgG1. 相似文献
108.
Complementary DNAs encoding precursor molecules of the beta subunits of three pituitary glycoprotein hormones (LH, FSH, and TSH) of the Japanese toad (Bufo japonicus) were isolated and sequenced. Unexpectedly large numbers of single nucleotide substitutions were found in all three beta subunit cDNAs. The eight isolated LH beta precursor cDNA clones were classified into six forms of nucleotide sequence, with four nucleotide substitutions each in the apoprotein coding region and in the 3' untranslated region (UTR). In the deduced amino acid sequence, the LH beta subunit showed two forms with a single amino acid substitution. The seven isolated FSH beta subunit cDNAs were classified into two forms, which differed from each other at 11 positions in the 3' UTR. The six isolated TSH beta subunit clones were classified into four forms with 2 and 5 nucleotide substitutions in the signal peptide and apoprotein coding regions, respectively. However, all the substitutions in the apoprotein coding region were silent. The substitution in the signal peptide coding region could produce three forms of signal peptide. Amino acid sequence comparison revealed that the toad LH beta subunit is more similar to the fish GTH II beta subunit than to mammalian and avian LH beta subunits. We found that the toad LH beta subunit molecule is a partial chimera of LH and FSH; amino acid residues located in 36th to 42nd and 96th to 99th are identical or similar to those of not LH- but FSH-beta subunit in mammalian, whereas it is more similar to LH- than FSH-beta subunit in total. We also found that the toad FSH beta subunit is more similar to the fish GTH II beta subunit than to the fish GTH I beta subunit and that the toad TSH beta subunit is more similar to tetrapod TSH beta subunits than to fish TSH beta subunits. 相似文献
109.
Embolization of Collateral Vessels Using Mechanically Detachable Coils in Young Children with Congenital Heart Disease 总被引:9,自引:0,他引:9
Sato Y Ogino H Hara M Satake M Oshima H Banno T Mizuno K Mishima A Shibamoto Y 《Cardiovascular and interventional radiology》2003,26(6):528-533
Our objective was to evaluate the usefulness of embolizing collateral vessels using mechanically detachable coils (MDCs) in children aged 3 years or younger with congenital heart disease. The subjects were 8 children with congenital heart disease featuring collateral vessels (age 18 days–3 years): 3 with a single ventricle, 2 with the tetralogy of Fallot, 2 with pulmonary atresia, and 1 with a ventricular septal defect. The embolized vessels were the major aortopulmonary collateral artery (MAPCA) in 5 patients, the persistent left superior vena cava in 2, and the coronary arteriovenous fistula in 1. A 4 or a 5 F catheter was used as the guiding device, and embolization was performed using MDCs and other conventional coils introduced through the microcatheter. One patient had growth of new MAPCAs after embolization, and these MAPCAs were also embolized with MDCs. Thus, a total of 9 embolization procedures were performed in 8 patients. Complete occlusion of the collateral vessels was achieved in 8 of 9 procedures (89%). Seven of 8 patients (88%) had uneventful courses after embolization, and MDC procedures appeared to play important roles in avoiding coil migration and achievement of safe coil embolization. One patient who underwent MAPCA embolization showed no improvement in heart function and died 2 months and 19 days later. Embolization of collateral vessels using MDCs in young children with congenital heart disease can be an effective procedure and a valuable adjunct to surgical management. 相似文献
110.
Is whole-brain irradiation necessary for primary central nervous system lymphoma? Patterns of recurrence after partial-brain irradiation 总被引:9,自引:0,他引:9
Shibamoto Y Hayabuchi N Hiratsuka J Tokumaru S Shirato H Sougawa M Oya N Uematsu Y Hiraoka M 《Cancer》2003,97(1):128-133
BACKGROUND: Neurotoxicity after whole-brain irradiation remains a major problem in the treatment of primary central nervous system lymphoma (PCNSL). To clarify whether whole-brain radiation is necessary for PCNSL, the authors retrospectively analyzed the outcome of patients treated with partial-brain irradiation. METHODS: A nationwide survey was performed regarding the treatment of PCNSL. Among 62 institutions surveyed, 7 were identified in which whole-brain irradiation was not necessarily employed. Questionnaires were sent to these institutions and 43 patients who had been treated using partial-brain fields since 1985 were collected. Thirty-two patients had solitary lesions and 11 had multiple lesions. Patterns of recurrence could be identified in 38 patients. RESULTS: The cumulative in-field and out-field recurrence rates at 5 years were 57% and 49%, respectively. Of 14 out-field recurrences, 2 occurred at the safety margin of the previous radiation field. The out-field recurrence rate was 45% in patients with a single lesion and 67% in those with multiple tumors (P = 0.79). The out-field recurrence rate was 22% for patients treated with safety margins of > or = 4 cm and 83% for those treated with safety margins of < 4 cm (P = 0.0079). The median survival time and the 5-year survival rate were 28.5 months and 20%, respectively, in the former group of patients and 15 months and 11%, respectively, in the latter group (P = 0.057). CONCLUSIONS: Focal radiotherapy with safety margins of < 4 cm appears to be associated with a very high rate of out-field recurrence, but the use of a radiation field with generous safety margins (> or = 4 cm) appears to be worth further investigation. 相似文献