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81.
Ferrand PE Fujimoto T Chennathukuzhi V Parry S Macones GA Sammel M Kuivaniemi H Romero R Strauss JF 《Molecular human reproduction》2002,8(11):1031-1034
Infection is believed to be a leading cause of preterm premature rupture of membranes (PPROM). The bacterial cell wall component, lipopolysaccharide (LPS), is thought to initiate tissue responses leading to PPROM in the setting of Gram negative infection. LPS is recognized by the innate immune system, including the proteins encoded by the CARD15 and TLR4 genes. A recently described mutation (2936insC) in CARD15 and a polymorphism in TLR4 896 A>G impair responses to LPS. The objective of this study was to determine if African Americans, who have a higher incidence of PPROM than Caucasians, have different frequencies of the mutant CARD15 allele and the TLR4 hyporesponsive variant, and if risk of PPROM is influenced by fetal carriage of these alleles. The allele frequencies for the CARD15 mutation and the TLR4 896G variant in African Americans were similar to those reported for Caucasians. There was no association between the TLR4 alleles examined and PPROM. However, the CARD15 mutation was only detected in controls and not in PPROM cases. We conclude that the CARD15 mutation and hyporesponsive TLR4 allele do not contribute to ethnic variation in the incidence of PPROM. 相似文献
82.
Tohru Yashiro Motohiko Aiba Takao Obara Yoshihide Fujimoto Akira Hirayama 《Pathology international》1988,38(3):371-381
A case of primary plasmacytoma of the thyroid gland which occurred in a 63-year-old woman is reported. Histologic and ultramicroscopic examination revealed that the excised thyroid tumor was plasmacytoma superimposed on lymphocytic thyroiditis. Immunohistological study showed that the tumor cells produced intracytoplasmic immunoglobulin (IgG-kappa). Electropho-retic and immunoelectrophoretic studies disclosed the presence of monoclonal immunoglobulin (IgG-kappa) in samples of the patient's serum which had been obtained preoperatively. After completion of irradiation therapy to the neck following tumor removal, the serum monoclonal immunoglobulin disappeared. The patient is currently alive and well without any evidence of the tumor three years after surgery. 相似文献
83.
B Lymphocyte signaling established by the CD19/CD22 loop regulates autoimmunity in the tight-skin mouse 下载免费PDF全文
Asano N Fujimoto M Yazawa N Shirasawa S Hasegawa M Okochi H Tamaki K Tedder TF Sato S 《The American journal of pathology》2004,165(2):641-650
Systemic sclerosis (SSc) is characterized by fibrosis and autoimmmunity. Peripheral blood B cells from SSc patients specifically overexpress CD19, a critical cell-surface signal transduction molecule in B cells. CD19 deficiency in B cells also attenuates skin fibrosis in the tight-skin (TSK/+) mouse, a genetic model for SSc. Herein we analyzed two transgenic mouse lines that overexpress CD19. Remarkably, 20% increase of CD19 expression in mice spontaneously induced SSc-specific anti-DNA topoisomerase I (topo I) antibody (Ab) production, which was further augmented by 200% overexpression. In TSK/+ mice overexpressing CD19, skin thickness did not increase, although anti-topo I Ab levels were significantly augmented, indicating that abnormal CD19 signaling influences autoimmunity in TSK/+ mice and also that anti-topo I Ab does not have a pathogenic role. The molecular mechanisms for abnormal CD19 signaling were further assessed. B-cell antigen receptor crosslinking induced exaggerated calcium responses and augmented activation of extracellular signal-regulated kinase in TSK/+ B cells. CD22 function was specifically impaired in TSK/+ B cells. Consistently, CD19, a major target of CD22-negative regulation, was hyperphosphorylated in TSK/+ B cells. These findings indicate that reduced inhibitory signal provided by CD22 results in abnormal activation of signaling pathways including CD19 in TSK/+ mice and also suggest that this disrupted B cell signaling contribute to specific autoantibody production. 相似文献
84.
Recently, the detection of side population (SP) cells, which have the ability to strongly efflux Hoechst 33342 fluorescence dye, has attracted attention as a method of stem cell isolation. We identified SP cells from mouse skin using the same method as from bone marrow. This population almost completely disappeared after treatment with the calcium channel blocker verapamil. SP cells were mainly localized in the epidermis, with a few in the dermis. The ratio of SP cells decreased as the mouse became older. Surface marker analysis revealed that the sorted SP cells expressed alpha6-integrin, beta1-integrin, Sca-1, keratin 14, and keratin 19, which are proliferating and progenitor cell markers, at levels higher than in non-SP cells, while they expressed E-cadherin, CD34, and CD71 at lower levels. The expression of breast cancer resistance protein 1 (BCRP1), which participates in dye efflux, was expressed at high levels at both the protein and mRNA level in sorted SP cells. Immunohistochemical analysis showed that BCRP1 was expressed in the basal layers and hair bulge regions of mouse skin. BCRP1 mRNA was found in basal layers and hair follicles of newborn skin by in situ hybridization. These results indicate that the localization of BCRP1-positive cells is compatible with that of keratinocyte stem cells. Based on the close relationship between BCRP1 and the SP cell phenotype, we conclude that keratinocyte stem cells are closely related to the SP- or BCRP1-positive cells. 相似文献
85.
Experimental induction of uterine cancer in rats by N-ethyl-N'-nitro-N-nitrosoguanidine dissolved in polyethylene glycol 总被引:2,自引:0,他引:2
H Ogino M Fujimoto H Oshiro K Matsumoto M Funahashi C Kaneko I Hirono 《Pathology, research and practice》1989,185(2):214-217
In the present experiment we attempted to experimentally induce uterine cancer in rats by injecting into the uterine cavity N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) dissolved in polyethylene glycol (PEG). Fifty-nine female F-344 rats, 7-8 weeks old, were divided into three groups and each received in the left uterine cavity with laparotomy a single dose of ENNG dissolved in PEG according to the following schedule: Group 1 received 75 mg ENNG/kg body wt.; Group 2 had 20 mg ENNG/kg body wt.: and Group 3 was given only PEG. In Group 1 it was observed that adenocarcinoma and sarcoma were present in the uterine corpus while squamous cell carcinoma occurred in the uterine cervix. In Group 2, although tumors such as adenocarcinoma, adenoma and sarcoma were observed in the uterine corpus, no tumor was present in the uterine cervix. No tumor growth whatsoever was observed in Group 3. From the above results it is apparent that the present method is an efficient means for experimentally inducing uterine cancer and that the site of tumor generation varies according to the concentration of ENNG administered. 相似文献
86.
Toshihiko Fujimoto Masatoshi Itoh Manabu Tashiro Keiichiro Yamaguchi Kazuo Kubota Hiroaki Ohmori 《European journal of applied physiology》2000,83(4-5):297-302
The purpose of this study was to examine, by positron emission tomography (PET), the distribution of [18F]fluoro-deoxy-glucose ([18F]FDG) uptake by human muscles during 35?min of running. Thirteen healthy male subjects were studied, seven of whom participated in the exercise study. Running intensity was kept constant such that the subjects' heart rates were maintained at between 140 and 150?beats per minute. [18F]FDG [62.9 (14.8)?MBq, mean (SD)] was injected after 15?min of running. PET imaging was started immediately after the running ended. The ratio of [18F]FDG uptake by muscles in runners to that in control subjects (r-c ratio) varied from three to six for the muscles of the foot and leg below the knee joint. The r-c ratio of the medial head of the gastrocnemius (MG) was higher than that of its lateral head (LG). The r-c ratio of the rectus femoris (RF) was lower than that of the other three muscles of the quadriceps femoris (QF). The r-c ratio of inactive muscles located above the waist was approximately 0.7. These results suggest that, during the moderate running of this study: (1) glucose uptake by muscles of the foot and leg below the knee joint clearly increases, (2) the r-c ratio differs significantly among the skeletal muscles, which act synergistically, and (3) glucose uptake by inactive skeletal muscles decreases. 相似文献
87.
Requirement of Runx1/AML1/PEBP2alphaB for the generation of haematopoietic cells from endothelial cells 总被引:3,自引:0,他引:3
88.
M Fujimoto I Sugawara M Kimoto S Ishizaka T Tsujii 《International journal of immunopharmacology》1986,8(3):323-328
In vitro effects of CCA, an anti-arthritis agent, were studied upon autologous mixed lymphocyte reaction (AMLR), lymphocyte mitogenesis, IL 1 and IL 2 production, immunoglobulin production and gamma-interferon (IFN) production. CCA at 50 micrograms/ml, which was not toxic to cells, blocked AMLR, IL 1 production and immunoglobulin production (IgM and IgG) significantly, while CCA at the same dose did not affect IL 2 production and lymphocyte mitogenic responses to Staphylococcus aureus Cowan I(SAC) and pokeweed mitogen(PWM). CCA at both 20 ng/ml and 20 micrograms/ml induced human gamma/IFN. Addition of IL 1 and/or IL 2 reversed inhibitory effect of CCA on AMLR. These data suggest that CCA exerts its actions by mainly affecting T cells and monocytes and can be used as an immunomodulator. 相似文献
89.
A sensitive double antibody enzyme immunoassay for the quantitation of cyclic AMP and cyclic GMP is presented. Specific antisera to each nucleotide were raised in rabbits by immunization with succinyl cyclic nucleotide-human serum albumin conjugates. For competitive reaction, antibodies were incubated with a mixture of succinyl cyclic nucleotide labelled with beta-D-galactosidase and unlabelled succinylated standard or sample cyclic nucleotides. The antibody-bound enzyme-hapten was separated from free hapten by anti-rabbit IgG immobilized to a polystyrene ball. Activity of the enzyme on the solid phase was fluorometrically determined. The assay system made it possible to ascertain values as low as 5 fmole of cyclic AMP or cyclic GMP. Cyclic nucleotides in plasma could be accurately determined by this method without requiring a deproteinizing reagent as the first step of assay. 相似文献
90.
M Imamura H Fujimoto S Hashino T Fukuhara M Kobayashi M Kasai K Sakurada T Miyazaki 《Immunobiology》1990,180(4-5):441-457
When we analyzed the in vivo efficacy of cytokine administration in murine allogeneic bone marrow chimeras, mitogen-induced responses to ConA, PHA, LPS, or PWM were increased by the in vivo administration of human recombinant granulocyte colony-stimulating factor (rG-CSF), human recombinant interleukin 2 (rIL-2), or WEHI-3B conditioned medium (CM). Furthermore, we found increased alloreactive mixed lymphocyte reactions (MLRs) against donor and/or host type alloantigens in spleen cells from (BALB/c----C3H/He) chimeras, although cytotoxic activity against BALB/c or C3H/He target cells was not detected in spleen cells from these chimeras. Since no significant increase of T cells or Ia positive cells was observed, some functional activation, rather than changes in the cell count, appeared to relate to increase immunoreactivity. An increased IL-2 production in spleen cells from chimeras injected with cytokine was observed shortly after the cessation of cytokine administration. Thereafter, an IL-2 production in these chimeras decreased around 45 days after bone marrow transplantation and then recovered nearly to the control level. An increased IL-2 responsiveness was also observed in spleen cells from these chimeras. These findings suggest that the in vivo administration of rG-CSF as well as rIL-2 or WEHI-3B CM (IL-3) can modulate the immunoreactivity in chimeras via the network of immune systems. 相似文献