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71.
Shahan TA Ohno N Pasco S Borel JP Monboisse JC Kefalides NA 《Connective tissue research》1999,40(3):221-232
Previous studies from our laboratories demonstrated that a peptide from the noncollagenous domain of the alpha3 chain of basement membrane collagen (COL IV), comprising residues 185-203, inhibits polymorphonuclear leukocyte activation and melanoma cell proliferation; this property requires the presence of the triplet -SNS- in residues 189-191 (Monboisse et al., J. Biol. Chem., 269, 25475, 1994; Han et al., J. Biol. Chem., 272, 20395, 1997). In the present study, we demonstrate that whole native COL IV and -SNS- containing synthetic peptides (10 microg/ml) added to culture medium inhibit the proliferation of not only melanoma cells, but also breast-, pancreas- and stomach-tumor cells up to 67%, and prostate tumor cells by 15%. ALC-COL IV at 5 microg/ml was shown to inhibit melanoma cell proliferation maximally at 69% and the alpha3(IV)185-203 peptide inhibited proliferation (62%) maximally at 10 microg/ml. Treatment of the alpha3(IV)185-203 peptide with either a specific mAb or a polyclonal antibody, prepared against the sequence alpha3(IV)179-208, decreased the ability of the peptide to inhibit cell proliferation by 97%, while treatment of ALC-COL IV with the same antibodies inhibited proliferation by 44%. Exposure of the above tumor cells to COL IV or the peptides resulted in an increase of intracellular cAMP that was inhibited by prior treatment of the protein with the above antibodies. To investigate the role of cAMP in the inhibition of cell proliferation, cAMP analogs and inhibitors were used. cAMP analogs mimicked the inhibitory effect of the peptide. Rp-cAMPS, a cAMP competitive inhibitor, suppressed the inhibitory effect of ALC-COL IV and of the cAMP analogs. The protein kinase-A inhibitor H-89 blocked the ability of ALC-COL IV and of the alpha3(IV)185-203 peptide to inhibit tumor cell proliferation. These data suggest that ALC-COL IV, through its alpha3(IV) chain, inhibits tumor cell proliferation utilizing a signal transduction pathway which includes cAMP and cAMP-dependent protein kinase(s). 相似文献
72.
Nidhi Sharma Atsushi Ohyabu Yoshiki Murakumo Masahide Takahashl Mitsuhiro Saito Hiroyuki Amo Shin-ichiro Murayama Kyoko Ohno Sen-ichi Oda Mutsushi Matsuyama 《Pathology international》1997,47(7):436-441
The thymoma prone BUF/Mna (B) rat is a useful model for Studying the genes responsible for thymus enlargement during the stage of young growth. Among the strains of rats, B rats have the largest thymuses at al stages of life. A locus, Ten-1 , which contributes to thymus enlargement in back-cross (BC) rats between the B and WKY/NCrj (W) strains, was mapped on chromosome 1. To determine the precise location of the bus, (B×(B×MITE)F1) BC rats were generated by crossing the B strain with the Inbred MITE (M) strain, which was established from captured, Japanese wild rats, and were examined by linkage study using polymerase chain reaction with 67 microsatellite markers. Linkages with thymus enlargements were found In genotypes of seven markers, BSIS, LSN, MYL2, IGF2, PBPC2, D1Mgh11 , and D1Mit6 , by X2- test and Student's t -test, which confirmed the presence of the genetic locus associated with thymus enlargement, Ten-1 , in this region. Paradoxically, a suppressive locus, Tsu-1 , to thymus enlargement was also found on chromosome 3, showing linkages of phenotype of the small thymus with genotypes of SCN2A, CAT D3Mit16 , and D3Mit13 . By analyses of mapmaker/exp and mapmaker/qtl, Ten-1 was mapped at 4.6 cM proximal from IGF2 locus on chromosome 1 and Tsu-1 at 4.0 cM proximal from CAT locus on chromosome 3, respectively. 相似文献
73.
Kojima M Nakamura S Shimizu K Hosomura Y Ohno Y Itoh H Yamane N Yoshida K Masawa N 《International journal of surgical pathology》2001,9(3):207-214
We report 11 Japanese cases of inflammatory pseudotumor (IPT) of the lymph node. There were 7 males and 4 females with ages ranging from 5 to 68 years (median; 48). Only 2 patients had systemic lymphadenopathy, and all others had involvement of only 1 lymph node group. Constitutional symptoms such as fever were present in 8 patients and laboratory abnormalities were detected in 5. All patients recovered and were alive and well after 2 to 180 months (median; 32 months). Histologically, the process mainly involved the connective tissue framework of the lymph node, secondarily spreading into the lymph node parenchyma and the perinodal tissue. It was characterized by a storiform growth pattern of myofibroblasts, marked vascularity with associated vascular lesions, and a polymorphous reactive cellular infiltrate in a collagen-rich stroma. An immunohistochemical study revealed numerous myofibroblasts, histiocytes, and vascular endothelial cells expressing vascular endothelial growth factor (VEGF) in 6 cases. It was suggested that VEGF may be involved, in part, in the induction of the angiogenesis of IPT. Moreover, the present study indicates that follicular dendritic cell sarcoma, nasal T/natural killer cell lymphoma, and anaplastic large cell lymphoma should be added to the differential diagnosis from IPT of the lymph node. Int J Surg Pathol 9(3):207-214, 2001 相似文献
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76.
BACKGROUND: Vernal keratoconjunctivitis (VKC) is characterized by severe ocular allergic inflammation that may have a poor visual prognosis. Due to the high frequency of the presence of atopic dermatitis (AD) in VKC, most systemic parameters are dependent on the clinical severity of AD. METHODS: Serum levels of sICAM-1, sVCAM-1, and sIL-2R were measured by enzyme-linked immunoassay using samples from 30 VKC patients, 30 allergic conjunctivitis (AC) patients, and 20 normal subjects, to determine whether the concentrations of these molecules are elevated. RESULTS: Circulating sICAM-1 and sIL-2R levels were increased in patients with VKC with AD compared with those in VKC without AD, AC, and normal controls. Serum levels of sVCAM-1 in VKC patients with and without AD were significantly higher than those in controls. No significant difference was found in the levels of sVCAM-1 between patients with VKC with and without AD. In VKC patients with AD, the sIL-2R level correlated significantly with severity of AD, whereas no such correlation was found for sICAM-1 and sVCAM-1. CONCLUSIONS: These results suggest that serum sVCAM-1 can be used as a marker to differentiate VKC from nonproliferative ocular allergic diseases, and specific immunologic features of VKC may underlie the upregulation of serum sVCAM-1. 相似文献
77.
Iijima M Brantley WA Kawashima I Ohno H Guo W Yonekura Y Mizoguchi I 《Biomaterials》2004,25(1):171-176
A micro-X-ray diffraction (micro-XRD) technique has been employed to determine the phases in two superelastic nickel-titanium orthodontic wires that exhibit shape memory in the oral environment and one superelastic nickel-titanium wire that does not exhibit shape memory in vivo. The micro-XRD analyses were performed over the clinically relevant temperature range of 0-55 degrees C, which corresponds to the ingestion of cold and hot liquids, and both straight and bent (135 degrees ) test samples were analyzed. The results showed that for straight (as-received) test samples, the rhombohedral phase (R-phase) was definitely present in one shape memory wire product and perhaps in the other shape memory wire product, but was apparently absent in the superelastic wire product that did not display shape memory. Martensite was observed in all three wire products after bending. Phase transformations occurred with temperature changes simulating the oral environment for straight test samples of the two shape memory wires, but the micro-XRD pattern changed minimally with temperature for straight test samples of the superelastic wire and for bent test samples of all three wire products. The phase transformations revealed by micro-XRD were consistent with results recently found by temperature-modulated differential scanning calorimetry. 相似文献
78.
S. Oh-ishi Takako Kizaki Tomomi Ookawara Koji Toshinai Shukoh Haga Fujio Karasawa Tetsuo Satoh Naokazu Nagata L. L. Ji Hideki Ohno 《Pflügers Archiv : European journal of physiology》1998,435(6):767-774
The aim of the current study was to elucidate the synergism of dietary calcium restriction and exhaustive exercise in the
antioxidant enzyme system of rat soleus muscle, and to investigate the involvement of neutrophils in exercise-induced muscle
damage. Forty-eight male Wistar rats were assigned to the following groups: control (C) or calcium-restricted [1 month (1 M)
or 3 months (3 M)]. Each group was subdivided into acutely exercised or non-exercised groups. Soleus muscle from each rat
was analysed to determine the levels of antioxidant enzymes [Mn-superoxide dismutase (SOD), Cu,Zn-SOD, glutathione peroxidase
(GPX), and catalase (CAT)]. Dietary calcium restriction resulted in calcium deficiency and upregulated the antioxidant enzymes
examined except GPX. Conversely, exhaustive exercise significantly decreased GPX and CAT, but not SODs activities in the calcium-restricted
(1 M and/or 3 M) rats. Contents of immunoreactive Mn-SOD and Cu,Zn-SOD were only increased in the 3 M rats. During calcium
restriction, the mRNA expression of both forms of SOD showed initial upregulation, followed by downregulation. Exhaustive
exercise significantly increased the mRNA expressions only in the 3 M rats. Moreover, exhaustive exercise markedly increased
myeloperoxidase activity in soleus muscles from the 1 M and 3 M rats compared with the C rats, and significantly enhanced
the ability of neutrophils to generate superoxide in the 3 M rats. The results demonstrate that dietary calcium restriction
upregulates certain antioxidant enzyme activities in rat soleus muscle, indicating an enhanced resistance to potential increases
in intracellular reactive oxygen species. The results also suggest that exhaustive exercise may cause oxidative damage in
soleus muscle of calcium-deficient rats through the activation of neutrophils.
Received: 4 August 1997 / Received after revision: 29 September 1997 / Accepted: 26 November 1997 相似文献
79.
Enhancement of the B-cell response to Staphylococcus aureus Cowan strain 1 by natural human gamma interferon. 下载免费PDF全文
The requirements for a primary, antigen-specific in vitro immunization of human peripheral lymphocytes using haemocyanin, a T-cell dependent antigen, have been studied. In order to obtain a specific response in vitro the peripheral lymphocytes had to be separated into B, T, accessory (A) and dendritic (D) cells. These cells were activated and reconstituted to give a population with a B:T ratio of 1:2. If the induction was supported by MHC-restricted, radioresistant T cells, this cell population could then be antigen-specifically activated using haemocyanin. The immunization had also to be supported by cytokines, such as B-cell growth and differentiation factors, interleukin-2 and gamma-interferon. A 5-day in vitro immunization using 2 micrograms haemocyanin/ml resulted in 200-300 cells secreting anti-haemocyanin-specific antibodies per 10(6) B cells. 相似文献
80.
Mizuki N Ota M Katsuyama Y Yabuki K Ando H Yoshida M Onari K Nikbin B Davatchi F Chams H Ghaderi AA Ohno S Inoko H 《Tissue antigens》2001,57(5):457-462
It is well known that Beh?et's disease (BD) is strongly associated with human leukocyte antigen (HLA) B51 in many ethnic groups. However, there has been no published report as yet with respect to this association among the Iranian people. Furthermore, since it is now known that the B51 antigen can be encoded by 21 alleles, B*5101-B*5121, we performed HLA-B*51 allele typing as well as HLA class I genotyping of 48 Iranian patients with this disease. As a result, the frequency of the B*51 allele was significantly higher (62.1%) in the patient group as compared with the ethnically matched control group (31.8%) (Pc=0.067, R.R.=3.51). In the genotyping of B*51 alleles, 33 out of the 36 B*51-positive patients possessed B*5101 and the remaining 3 carried B*5108. This study revealed that Iranian patients with BD also had a strong association with HLA-B51. In addition, this significantly high incidence of HLA-B*51 was found to be caused by an increase in both the HLA-B*5101 and HLA-B*5108 alleles. However, there was no significant difference in the HLA-B*51 allelic distribution between the patient and control groups. 相似文献