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51.
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation.  相似文献   
52.
TCR repertoire in early fetal mouse thymus   总被引:1,自引:0,他引:1  
We investigated the rearrangement and expression of TCR genesin mouse fetal thymus organ culture, a system that avoids subsequententry of hematopoietic precursor cells. The first observablerearranged TCR gene was homogeneous V2-J2, detectable as earlyas fetal day 11 (d11) in the thymic primordla. The productiveTCR was homogeneous V5-J1, first detectable in d13 thymocytes,followed by adult-type TCR (V4 and V7). Sequence analysis ofTCR revealed five types of V-J junctional sequences. In thevery early stage, a homogeneous V-J junction is generated viaa short homology sequence in the coding region (Type I), whilea short homology sequence in the P-nucleotlde rather than thecoding region is used in the following stage (Type II). In thelater embryonic stages, diverse V-J junctions are generatedby well-known mechanisms, such as P-nucleotide (Type III), N-regioninsertion (Type IV) or trimming of the coding ends (Type V).These findings suggest that the generation of homogeneous TCR (V2 and V5) in the early fetal stages is due to the intrinsicrearrangement mechanisms and is in stage specific manner.  相似文献   
53.
A modified SiO2 was prepared by reacting SiO2 with Cl2Si(CH3)2 in toluene, on which methylaluminoxane (MAO) was supported to obtain a catalyst precursor. The mixture of the precursor and Cp2ZrCl2 (Cp: cyclopentadienyl) gave polyethylene in a high yield even by using common trialkylaluminiums as cocatalyst. Surprisingly, the MAO-free catalyst system composed of the modified SiO2 and Cp2ZrCl2 was also found to be activated by common trialkylaluminiums.  相似文献   
54.
The inhibitory effect of an antiserum to surface protein P50 of Babesia gibsoni on the growth of the parasite was determined with severe combined immunodeficiency mice given canine red blood cells. The antiserum to the recombinant P50 protein significantly inhibited the parasite growth, indicating that P50 might be a useful vaccine candidate.  相似文献   
55.
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002  相似文献   
56.
The early experience is reported here of the use of Intra-operative frozen-section service by telepathology using the Integrated Service Digital Network (ISDN), a commercially available system that is being connected between the Department of Pathology of Tottori University and Matsue City Hospital, a distance of 30 km. The transfer rate is currently 64kbit/s. The frozen-section service was conducted for a total of 117 tissue specimens (organs) from 100 patients between August 1993 and May 1995. The average time taken for examination of each specimen of frozen section was 13min, ranging between 2 and 42min. The average number of transmitted Images was 6.2. Six cases necessitated more than 11 transmitted Images to make a diagnosis, while 13 cases could be diagnosed from two images only. Correct and permissible diagnoses were obtained in 109 (93.2%) out of 117 specimens when comparing the telepathology diagnosis with that of direct microscopy. Improper or misdiag-nosis was made for eight cases (specimens), which were misinterpreted as papillary carcinoma in Basedow's disease, adenoma and hyperplasia in two pheochromocytomas, solid-tubular carcinoma in phyilodes tumor, mastopathy in invasive carcinoma, metastatic carcinoma in astrocytoma, follicular lymphoma in reactive hyperplasia, and lymphadenitis in follicular lymphoma. in retrospect, diagnosis of these cases should have been deferred. From the results, it was concluded that the Intraoperatlve frozen-section service by telepathology may be a worthwhile substitute for hospitals with limited accessibility to local pathology service, in spite of pitfalls in some cases. Well prepared, high-quality frozen sections, sufficient verbal communication with surgeons, and a rather conservative attitude on the part of a well-trained pathologist seem to be the essential Ingredients for reaching an accurate decision when using telepathology.  相似文献   
57.
Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) solely induce arthritis in mice. High titers of anti-GPI Abs are found in some patients with rheumatoid arthritis (RA), but their pathogenic role remains elusive. The aim of this study was to evaluate the pathogenic role of anti-GPI Abs in cynomolgus monkeys. IgG fractions were separated from sera of anti-GPI Abs-positive RA patients and healthy subjects and directly injected into the metacarpophalangeal joints of 4 cynomolgus monkeys. At day 16, the joints were harvested and examined histologically and immunohistochemically. The expression of C5a receptor (C5aR) molecule in the synovium was quantified by real-time PCR using cDNA from monkey joints. In monkey joints, IgG including anti-GPI Abs resulted in recruitment of granulocytes and mononuclear cells, strong deposition of human IgG on the articular surface, and overexpression of C5aR, but no joint swelling. No infiltrated cells or IgG deposition were observed in monkeys injected with IgGs from healthy subjects. Our results suggest that IgG fraction from RA patients including anti-GPI Abs may play a crucial role in the generation of synovitis in monkeys, although the pathogenesis of anti-GPI Abs in RA patients is still uncertain.  相似文献   
58.
59.
The immunoreactivity of albumin (ALB) was observed in the hepatocytes of fetal rats on day 18 of gestation, and was especially observable in immature rough endoplasmic reticulum (rER) and Golgi apparatus (GA); by then, a small amount of silver grains of ALB mRNA could already be detected. Just after birth, immunoreactivity of ALB could be observed in fine granules or diffusely in all hepatocytes, and was present in rER and GA. One week after birth immunoreactivity of ALB was observed in all hepatocytes and was visible in developed rER and GA; the grains of ALB mRNA were present in all hepatocytes.  相似文献   
60.
Our recent studies on an autoantibody-transgenic mouse linedemonstrated that peritoneal B-1 cells are responsible for autoimmunesymptoms. However, whether B-1 cells in the peritoneum are generallyinvolved in the pathogenesis of autoimmune disease remains controversial.To test the possible involvement of peritoneal B-1 cells inautoimmune symptoms of autoimmune-prone NZB mice, we eliminatedthe peritoneal cells by hypotonic shock with repeated I.p. injectionof distilled water every 7 days into neonatal or 8-week-oldNZB mice. By this treatment, B-1 cells, which self- renew withinthe peritoneal cavity, are expected to be preferentially eliminated,while other peritoneal cells can be easily supplied from bonemarrows after this treatment indeed, in distilled water-treatedold NZB mice, the number of B-1 cells decreased in spleen aswell as in lamina propria of the gut but the numbers of conventionalB cells and T cells did not change. Moreover, the productionof autoantibodies against erythrocytes significantly decreasedand the occurrence of autoimmune hemolytic anemia was reducedin 12-month-old treated NZB mice. Similarly, the eliminationof peritoneal cells of NZB/NZW (NZB/W) F1; mice by water injectiondecreased anti-DNA IgG antibodies in the sera and reduced thepathological changes of the kidney. These results suggest thatperitoneal B-1 cells may be a source of autoantibody-producingcells in autoimmune diseases of NZB and NZB/W F1; mice.  相似文献   
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