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11.
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of autoantibodies and lupus nephritis. In the present study using New Zealand Black (NZB) x New Zealand White (NZW) F1 (NZBW F1) mice, we planned to investigate the effects of Toxoplasma gondii infection on the progress of lupus nephritis. Female NZBW F1 mice at the age of 2 months were perorally infected with T. gondii. The T. gondii infection reduced the number of mice developing proteinuria and immune complex deposits in their kidneys and prolonged their life span. A marked decrease in the levels of IgM and IgG anti-DNA antibodies, especially IgG2a and IgG3 subclasses, was observed in T. gondii-infected NZBW F1 mice at 9 months of age. The level of anti-HSP70 IgG autoantibody in the sera of NZBW F1 mice was significantly higher than that in control mice at 9 weeks after T. gondii infection. Moreover, NZBW F1 mice treated with anti-self heat shock protein 70 (HSP70) monoclonal antibody were substantially protected against the onset of glomerulonephritis. Further, down-regulation of intracellular expression of IFN-gamma and IL-10 was shown in spleen cells of T. gondii-infected NZBW F1 mice. This was consistent with the previous data indicating the involvement of Th1-type and Th2-type cytokines in the development of lupus-like nephritis. These results suggest that T. gondii infection is capable of preventing the development of autoimmune renal disorder in NZBW F1 mice.  相似文献   
12.
Summary In this investigation, 83 human mammary carcinomas were examined for the expression of oestrogen receptor (ER), epidermal growth factor receptor (EGF-R), epidermal growth factor (EGF), transforming growth factor alpha (TGF-), c-erbB-2, histological grade, mitotic index and nodal status, all of which are reportedly prognostically significant factors (Bloom and Richardson 1957; Baak et al. 1985; Wright et al. 1989). ER expression was biochemically recognized in 43.4% of mammary carcinomas, and EGF-R, EGF, TGF- and c-erbB-2 were histochemically recognized in 25.3, 14.5, 27.7 and 18.0% of mammary carcinomas examined respectively, using conventional sections of buffered formalin-fixed, paraffin-embedded tissue and monoclonal or polyclonal antibodies. There were significant relationships between negative ER and positive EGF-R or TGF-; positive EGF-R and TGF-; positive EGF-R and c-erbB-2; and positive c-erbB-2 and TGF-. The single changes which were the negative ER and the positive c-erbB-2 correlated with histological grade and mitotic index. Co-expression of EGF-R and TGF- correlated with positive nodal status. Therefore, the present investigation indicates that the negative ER, single expression of c-erbB-2 and co-expression of EGF-R and TGF- are important markers which contribute indirectly to prognosis, which reconfirms previous findings on the former two while adding the new finding that immuno-histochemical demonstration of expression of EGF-R and TGF- may provide useful information for selecting the appropriate treatment.  相似文献   
13.
14.
To investigate the role of the Toll-like receptor (TLR) family in host defense against Toxoplasma gondii, we infected TLR2-, TLR4- and MyD88-deficient mice with the avirulent cyst-forming Fukaya strain of T. gondii. All TLR2- and MyD88-deficient mice died within 8 days, whereas all TLR4-deficient and wild-type mice survived after i.p. infection with a high dose of T. gondii. Peritoneal macrophages from T. gondii-infected TLR2- and MyD88-deficient mice did not produce any detectable levels of NO. T. gondii loads in the brain tissues of TLR2- and MyD88-deficient mice were higher than in those of TLR4-deficient and wild-type mice. Furthermore, high levels of IFN-gamma and IL-12 were produced in peritoneal exudate cells (PEC) of TLR4-deficient and wild-type mice after infection, but low levels of cytokines were produced in PEC of TLR2- and MyD88-deficient mice. On the other hand, high levels of IL-4 and IL-10 were produced in PEC of TLR2- and MyD88-deficient mice after infection, but low levels of cytokines were produced in PEC of TLR4-deficient and wild-type mice. The most remarkable histological changes with infiltration of inflammatory cells were observed in lungs of TLR2-deficient mice infected with T. gondii, where severe interstitial pneumonia occurred and abundant T. gondii were found.  相似文献   
15.
The number of inflammatory cells was studied in lung walls and airways after inhalation of endotoxin or -1,3-glucan. In the water unsoluble form, -1,3-glucan caused a delayed response in terms of a decrease in macrophages and lymphocytes in the lung wall, 1 to 7 days after exposure but no invasion of neutrophils into the airways. When solubilized in 0.02 N NaOH, the cell response was the same as that observed after exposure to endotoxin.  相似文献   
16.
The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis.  相似文献   
17.
2-O-methylisohemigossylic acid lactone, a sesquiterpene, was purified from roots of mokumen (Gossampinus malabarica) and identified by Mass, and (1)H- and (13)-NMR. This sesquiterpene displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells. Apoptotic morphological change of the nucleus, including chromatin condensation was induced in the HL-60 cells treated with the sesquiterpene. The fragmentation of DNA by the sesquiterpene to oligonucleosomal-sized fragments, a characteristic of apoptosis, was observed to be dose- and time-dependent in the HL-60 cells. Inhibitors of caspases suppressed the DNA fragmentation induced by the sesquiterpene. These findings suggest that growth inhibition by the sesquiterpene of HL-60 cells results from the induction of apoptosis by the sesqui-terpene, and that caspase cascade is involved in the induction of apoptosis by the compound in the HL-60 cells.  相似文献   
18.
Chiral poly(crown ether)s were synthesized by cationic cyclopolymerization of (S)-2,2′-bis(2-vinyloxyethoxy)-3,3′-dimethyl-1,1′-binaphthyl [(S)- 1b ] and (R)-2,2′-bis[2-(2-vinyloxyethoxy)-ethoxy]-3,3′-dimethyl (or 3,3′-diphenyl)-1,1′-binaphthyl [(R)- 3b or (R)- 3c ]. The substituents in the 3,3′-positions of binaphthyl moiety disturb the intramolecular cyclization in the polymerization of monomer (S)- 1b , but have no influence on the cyclopolymerization tendency of monomers (R)- 3b and (R)- 3c . The polymers from (R)- 3b and (R)- 3c [(R)- 4b and (R)- 4c ] have a higher ability of chiral recognition towards a-amino acids, such as phenylglycine, phenylalanine, valine, and methionine, than the polymer from (R)- 3a [(R)- 4a ], which has no substituent in 3,3′-positions. The methyl and the phenyl substituents in the 3,3′-positions undoubtedly act as additional barrier causing an increase in the ability of chiral recognition, though the effect is less than expected from the result of model crown ethers.  相似文献   
19.
Summary The relationship between the accumulation of isoprenaline and the incidence and duration of ventricular fibrillation was investigated in the perfused rat heart. Isolated rat hearts were perfused with 3H-isoprenaline (1 mol/l) for 30 min at a constant flow rate of 6.5 ml/min at a temperature between 40 and 41° C. Electrocardiograms were recorded during the perfusion period and the isoprenaline content of the tissue was measured after the perfusion. The accumulation of isoprenaline was significantly increased and the duration of ventricular fibrillation was significantly prolonged by the presence of tropolone (100 mol/l). When extraneuronal uptake inhibitors such as normetanephrine (100 mol/l), 3-O-methylisoprenaline (100 mol/l) or phenoxybenzamine (1 mol/l) were added to the perfusion fluid containing 3H-isoprenaline (1 mol/l) and tropolone (100 mol/l), the accumulation of isoprenaline was sifnificantly decreased, the incidence of ventricular fibrillation was significantly reduced and the duration of ventricular fibrillation was significantly shortened. There was a significant correlation for dependence of duration of ventricular fibrillation on the isoprenaline content of rat hearts perfused with various extraneuronal uptake inhibitors in the presence of tropolone (correlation coefficient [r]=0.62, P<0.001).These results indicate that the accumulation of isoprenaline in perfused rat hearts relates to the occurrence and duration of ventricular fibrillation.This study was supported in part by a Grant-in-Aid for Scientific Research (59570980) from the Ministry of Education, Science and Culture, Japan  相似文献   
20.
Malnutrition is a core symptom of the frailty cycle in older adults. The purpose of this study was to investigate whether dysphagia influences nutrition or frailty status in community-dwelling older adults. The study participants were 320 Japanese community-dwelling older adults aged ≥65 years. All participants completed a questionnaire survey that included items on age, sex, family structure, self-rated health, nutritional and frailty status, and swallowing function. Nutritional status was categorized as malnourished, at risk of malnutrition, and well-nourished based on the Mini Nutrition Assessment-Short Form. The participants were then classified into a malnutrition (malnourished/at risk) or a well-nourished group (well-nourished). Frailty was assessed using the Cardiovascular Health Study criteria. The participants were then divided into a frailty (frail/pre-frail) or a non-frailty group (robust). Dysphagia was screened using the 10-item Eating Assessment Tool. Multiple logistic regression analysis was conducted to determine whether dysphagia was associated with nutritional or frailty status. The results revealed that dysphagia influenced both nutrition (odds ratio [OR]: 4.0; 95% confidence interval [CI]: 1.9–8.2) and frailty status (OR: 2.3; 95% CI: 1.0–5.2); therefore, the swallowing function would be an important factor for community-dwelling older adults on frailty prevention programs.  相似文献   
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