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31.
BACKGROUND: We previously reported that adenovirus mediated CD40Ig gene therapy (AdCD40Ig) induced long-term acceptance of fully allogeneic rat cardiac allografts, however, the underlying mechanism has not been fully clarified. To address this we have compared the ability of dimeric and monomeric soluble CD40 to prolong allograft survival in vivo and generate regulatory T cells in vitro. METHODS: The ability of CD40Ig (soluble dimmer, containing an Fc region) or CD40/Myc/His (soluble monomer, lacking an Fc region) therapy to generate CD4CD25 regulatory T cells in vitro and to prevent rejection of rat cardiac allografts (ACI to LEWIS) was compared. Immunoregulatory capacity of regulatory T cells generated was determined by suppression of alloantigen specific proliferation and cytotoxicity. RESULTS: Dimeric soluble CD40Ig did not inhibit CD4 T cell proliferation but rather promoted IL-2 production and the generation of CD4CD25 T cells, which regulated alloantigen-specific cytotoxic T lymphocyte activity. Treatment with either AdCD40Ig or purified soluble CD40Ig prolonged the survival of rat cardiac allografts. In contrast, although monomeric soluble CD40/Myc/His suppressed IL-12 production in a similar manner to that achieved by CD40Ig, it did not augment IL-2 production. Moreover, while CD40/Myc/His also generated CD4CD25 T cells, they did not exhibit regulatory activity and administration of soluble CD40/Myc/His failed to prolong cardiac allograft survival. CONCLUSIONS: These results suggest signaling through CD154 in addition to blocking of CD154-CD40 interaction is important for the immunomodulatory effects of soluble CD40Ig. Taken together, our results provide new insight into the mechanism of immunomodulation by soluble CD40 constructs.  相似文献   
32.
We report on 10 patients who underwent two-stage repair of transposition of the great arteries (TGA) with interruption (IAA) or coarctation (CoA) of the aorta. First, an operation for aortic arch reconstruction was performed: Blalock-Park with pulmonary artery banding (PAB) for IAA (5 patients), subclavian flap with PAB for CoA (4 patients) and end-to-end anastomosis without PAB (1 patient). All survived the first operation and had no significant pressure gradient with good growth of the ascending aorta, except for the 1 case without PAB. Half of the 8 patients who underwent PAB developed migration of the PAB. The arterial switch operation (ASO) was performed 0.7-12.6 (5.6+/-4.7) months after the first surgery. One patient with an abnormal coronary artery tract was lost after ASO. Five developed pulmonary artery stenosis and 1 developed supra-aortic stenosis late after ASO. Two patients need reoperation, 1 for supra-aortic stenosis, and the other for reCoA. Two-stage repair for TGA with IAA/CoA is still a useful method with a good operative result. However, strict follow-up is necessary because of the high frequency of late morbidity.  相似文献   
33.
Trans-tympanic silicone plug insertion for chronic patulous Eustachian tube   总被引:3,自引:0,他引:3  
CONCLUSION: Trans-tympanic insertion of a new silicone plug seems to be useful for controlling the distressing symptoms of patients with a chronic patulous Eustachian tube (PET). OBJECTIVE: To evaluate the effectiveness of a new silicone plug for blocking the isthmus of a PET in patients whose symptoms were resistant to other therapies for > 6 months. MATERIAL AND METHODS: The silicone plug (total length 23-25 mm; tip diameter 1.0-2.0 mm) was inserted in 44 ears of 37 patients with chronic PET. It was inserted through the tympanic orifice of the ET to obstruct the isthmus of the tube via an incision in the anterosuperior portion of the tympanic membrane. RESULTS: Insertion of the plug was possible in all except two ears, in which it failed because of a narrow tympanic orifice of the ET. In 11 ears of 10 patients, the plug was replaced by a larger one using the same approach to improve efficacy. Of the 42 ears in which the silicone plug was successfully inserted, 30 (71.4%) achieved relief from symptoms of PET without additional treatment. In > 60% of these cases, the symptoms of PET were well controlled with an aerated middle ear. The follow-up period ranged from 6 to 68 months (mean 38.9 months).  相似文献   
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A 28-day in vivo treatment trial to evaluate the efficacy of pyrimethamine/sulfadoxine (Fansidar, PS) was conducted in 21 Lao patients with uncomplicated Plasmodium falciparum malaria. Sixteen patients (76%) were completely cured with PS without any reappearance of asexual stage parasitemia during the follow-up examination. On the other hand, 5 patients (24%) failed to respond to this trial medication, resulting in recrudescence of asexual stage P. falciparum malaria. PS resistance resulted in higher prevalence of post-treatment gametocytemia, 25% gametocyte carriers among PS sensitive cases versus 75% of the resistant cases. These findings suggest that although the level of PS resistance is still valid for treatment of malaria in the study area of Lao PDR, post-treatment induction of gametocytemia among resistant cases may result an increase in transmission rate of PS resistant falciparum malaria.  相似文献   
36.
Measles virus was isolated from the middle ear fluid (MEF) of two infant cases of acute otitis media (AOM) associated with measles. This is the first report on the isolation of measles virus from the MEF in patients with AOM, and possibility of the measles virus as a causative agent of AOM was suggested.  相似文献   
37.
We describe a gastric carcinoma cell line that has been maintained in vitro for more than 10 years and retains the capacity to produce a large amount of alpha-fetoprotein. This cell line was isolated from a metastatic lymph node of a 63-year-old male patient with advanced gastric carcinoma (T2N3P0H0M0) who showed high serum levels of alpha-fetoprotein. The primary tumor was moderately differentiated tubular adenocarcinoma and the lymph node was poorly differentiated adenocarcinoma without any particular pattern. The cultured cells grew as densely packed islet-like colonies with small polygonal cells. Electron microscopy revealed cells abundant in cytoplasmic organelles, with some cellular attachments being tight with junctional complexes and some being loose across intercellular spaces. The free cell surface had microvilli. The population doubling-time was 152 h at passage 58. Chromosomal analysis revealed the modal number to be 77, with numerous karyotype abnormalities. The tumorigenicity of the cultured cells in athymic nude mice was positive only when they were subcutaneously transplanted beneath a plastic plate, but when the cells were transplanted subcutaneously or administered by intrasplenic injection in intact or weakly irradiated nude mice, no tumorigenicty was shown. The cell line produced tumor-associated antigens, such as alpha-fetoprotein, carcinoembryonic antigen, and tissue polypeptide antigen. This cell line may be useful for comparative studies of different types of gastric carcinoma and alpha-fetoproteins of different origins.  相似文献   
38.
Perlman syndrome is a rare, autosomal recessive overgrowth disorder. Recently, the deletion of exon 9 and other mutations of the DIS3L2 gene have been reported in patients; however, the mechanism behind this deletion is still unknown. We report the homozygous deletion of exon 9 of DIS3L2 in a Japanese patient with Perlman syndrome. We identified the deletion junction, and implicate a non-allelic homologous recombination (NAHR) between two LINE-1 (L1) elements as the causative mechanism. Furthermore, the deletion junctions were different between the paternal and maternal mutant alleles, suggesting the occurrence of two independent NAHR events in the ancestors of each parent. The data suggest that the region around exon 9 might be a hot spot of L1-mediated NAHR.  相似文献   
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OBJECTIVE: To investigate the involvement of osteopontin (OPN) in bone destruction in a murine experimental arthritis model of collagen-induced arthritis (CIA). METHODS: The expression of OPN was examined at both the messenger RNA (mRNA) and protein levels in various arthritic lesions in mice with CIA by in situ hybridization and immunohistochemistry, respectively. In addition, the expression of alpha(v)beta3 integrin, a receptor for OPN, the ligation of which is thought to be essential for bone resorption by osteoclasts, was examined by immunohistochemistry. Plasma concentrations of OPN were measured at different time points in the course of CIA by enzyme-linked immunosorbent assay. RESULTS: OPN mRNA was detected mainly at sites of bone erosion in arthritic lesions, where activated osteoclasts were present; OPN protein was also detected at sites of bone erosion. In the arthritic synovium, OPN was predominantly expressed in the synovial lining layer, but not in lymphoid aggregates. In addition, alpha(v)beta3 integrin was detected coincident with OPN at sites of bone erosion (bone-pannus junction). Plasma OPN levels were markedly elevated at the time points that corresponded to arthritis flares, and higher levels were maintained during the progression of arthritis. CONCLUSION: OPN may mediate bone resorption by osteoclasts in arthritis through ligation with its receptor, alpha(v)beta3 integrin. OPN may be a useful therapeutic target molecule in the prevention of bone destruction in arthritis.  相似文献   
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