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61.
A mAb J43 has been produced against the product of the mousePD-1 gene, a member of the Ig gene superfamily, which was previouslyisolated from an apoptosis-induced T cell hybridoma (2B4.11)by using subtractive hybridization. Analyses by flow cytometryand immunoprecipitation using the J43 mAb revealed that thePD-1 gene product is a 50–55 kDa membrane protein expressedon the cell surface of several PD-1 cDNA transfectants and 2B4.11cells. Since the molecular weight calculated from the aminoacid sequence is 29,310, the PD-1 protein appears to be heavilyglycosylated. Normal murine lymphoid tissues such as thymus,spleen, lymph node and bone marrow contained very small numbersof PD-1+ cells. However, a significant PD-1+ population appearedin the thymocytes as well as T cells in spleen and lymph nodesby the in vivo anti-CD3 mAb treatment. Furthermore, the PD-1antigen expression was strongly induced in distinct subsetsof thymocytes and spleen T cells by in vitro stimulation witheither anti-CD3 mAb or concanavalin A (Con A) which could leadT cells to both activation and cell death. Similarly, PD-1 expressionwas induced on spleen B cells by in vitro stimulation with anti-IgMantibody. By contrast, PD-1 was not significantly expressedon lymphocytes by treatment with growth factor deprivation,dexamethasone or lipopolysaccharide. These results suggest thatthe expression of the PD-1 antigen is tightly regulated andinduced by signal transduction through the antigen receptorand do not exclude the possibility that the PD-1 antigen mayplay a role in clonal selection of lymphocytes although PD-1expression is not required for the common pathway of apoptosis.  相似文献   
62.
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data.  相似文献   
63.
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function.  相似文献   
64.
The mechanical activity of the human quadriceps muscle during maximal incremental cycle ergometry was investigated by mechanomyography (MMG). MMG and surface electromyography (EMG) recordings of vastus lateralis muscle activity were obtained from nine males. Cycle ergometry was performed at 60?rev/min and work load was incremented step wise by 20?W (3.2?Nm) every minute until volitional fatigue. The mean amplitudes of MMG (mMMG) and EMG (mEMG) during the contraction phase were calculated from the last six contractions in each load. The duration, load and work rate of exercise at exhaustion were 13.3 (1.6)?min, 44.1 (5.5)?Nm, 276.7 (34.7)?W, respectively. A linear relationship between mMMG and load was evident in each subject (r?=?0.868–0.995), while mEMG seemed to dissociate as the load became greater. In the grouped mean data, mMMG was linearly related to load whether aligned to the absolute (r?=?0.995) or maximal (r?=?0.995) load. Involvement of the noise component was further investigated by studying passive cycling by four subjects. Pedals were rotated passively for the first half of each stage (PAS) and the subject then pushed the pedals for the second half (ACT). In the lighter load region, the mMMG of ACT was as small as that of PAS. However, the change in the mMMG of PAS was very small compared with that of ACT. In conclusion, this study demonstrates a linear relationship between the mMMG of the quadriceps muscle and work load during maximal incremental cycle ergometry. The effect of movement noise was thought to be small and stable.  相似文献   
65.
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle.  相似文献   
66.
The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor.  相似文献   
67.
In an attempt to clarify the cytological characteristics of the RES cells in the lymph nodes and their embryological correlations, lymph nodes and lymph node anlages of germ-free rats, nude mice, and human fetuses were light and electron microscopically examined. On the basis of differences of intracellular organelles, their behaviors for reticulum fibers and of endogenous peroxidatic activity, histiocytes should be reasonably distinguished from the cells conventionally called reticulum cells. Reticulum cells and histiocytes respectively are destined to differentiate in different directions from the early stage of development of the lymph node anlage. Sinus endothelial cells are ontogenetically originated and differentiated from the endothelial lining cells of lymphatic vessels. Primitive reticular cells are differentiated into mature reticulum cells in the lymph nodes, they transform into the lympho-reticular cells, further into lymphoblasts, and finally develop into medium-sized lymphocytes.  相似文献   
68.
A new type of cryptochrome, CRY-DASH, has been recently identified. The CRY-DASH proteins constitute the fifth subfamily of the photolyase/cryptochrome family. CRY-DASHs have been identified from Synechocystis sp. PCC 6803, Vibrio cholerae, and Arabidopsis thaliana. The Synechocystis CRY-DASH was the first cryptochrome identified from bacteria, and its biochemical features and tertiary structure have been extensively investigated. To determine how broadly the subfamily is distributed within living organisms, we searched for new CRY-DASH candidates within several databases. We found five sequences as new CRY-DASH candidates, which are derived from four marine bacteria and Neurospora crassa. We also found many CRY-DASH candidates from the EST databases, which included sequences from fish and amphibians. We cloned and sequenced the cDNAs of the zebrafish and Xenopus laevis candidates, based on the EST sequences. The proteins encoded by the two genes were purified and characterized. Both proteins contained folate and flavin cofactors, and have a weak DNA photolyase activity. A phylogenetic analysis revealed that the seven candidates actually belong to the new type of cryptochrome subfamily. This is the first report of the CRY-DASH members from vertebrates and fungi.  相似文献   
69.
The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease, very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy. Part of this paper was presented at the 42nd JSAO Conference (Tokyo, October 5–7, 2004)  相似文献   
70.
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo.  相似文献   
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