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601.
Hiyoshi K Ichinose T Sadakane K Takano H Nishikawa M Mori I Yanagisawa R Yoshida S Kumagai Y Tomura S Shibamoto T 《Environmental research》2005,99(3):361-368
Asian sand dust (ASD) containing sulfate (SO4(2-)) reportedly causes adverse respiratory health effects but there is no experimental study showing the effect of ASD toward allergic respiratory diseases. The effects of ASD and ASD plus SO4(2-) toward allergic lung inflammation induced by ovalbumin (OVA) were investigated in this study. ICR mice were administered intratracheally with saline; ASD alone (sample from Shapotou desert); and ASD plus SO4(2-) (ASD-SO4); OVA+ASD; OVA+ASD-SO4. ASD or ASD-SO4 alone caused mild nutrophilic inflammation in the bronchi and alveoli. ASD and ASD-SO4 increased pro-inflammatory mediators, such as Keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-1 alpha, in bronchoalveolar lavage fluids (BALF). ASD and ASD-SO4 enhanced eosinophil recruitment induced by OVA in the alveoli and in the submucosa of the airway, which has a goblet cell proliferation in the bronchial epithelium. However, a further increase of eosinophils by addition of SO4(2-) was not observed. The two sand dusts synergistically increased interleukin-5 (IL-5) and monocyte chemotactic protein-1 (MCP-1), which were associated with OVA, in BALF. However, the increased levels of IL-5 were lower in the OVA+ASD-SO4 group than in the OVA+ASD group. ASD caused the adjuvant effects to specific-IgG1 production by OVA, but not to specific-IgE. These results suggest that the enhancement of eosinophil recruitment in the lung is mediated by synergistically increased IL-5 and MCP-1. IgG1 antibodies may play an important role in the enhancement of allergic reaction caused by OVA and sand dust. However, extra sulfate may not contribute to an increase of eosinophils. 相似文献
602.
F. Shishido K. Uemura A. Inugami N. Tomura S. Higano H. Fujita H. Sasaki I. Kanno M. Murakami Y. Watahiki K. Nagata 《Neuroradiology》1996,38(2):102-107
Cerebral blood flow (CBF), oxygen metabolism (CMRO2), and glucose metabolism (CMRGlc) were measure using positron emission tomography in five patients diagnosed as having mitochondrial encephalomyopathy. The molar ratio between the oxygen and glucose consumptions was reduced diffusely, as CMRO2 was markedly decreased and CMRGlc was slightly reduced. The CBF showed less changes. The CBF increase on hypercapnia was smaller than normal, though this was not significant. CBF with hypocapnia demonstrated a significant reduction compared with the normal. These results suggest that oxidative metabolism is imparied and anaerobic glycolysis relatively stimulated, due to a primary defect of mitochondrial function, and that mild lactic acidosis occurs in brain tissue because of impaired utilisation of pyruvate in the TCA cycle. As these findings appear to indicate directly a characteristic of this disease, such measurements may be a useful tool for assessment of the pathophysiology and for diagnosis of mitochondrial encephalomyopathy. 相似文献
603.
The cervical carotid Doppler velocity is determined by the cardiovascular function, hemodynamic characteristics of proximal vascular beds, the carotid artery, and the distal vascular beds, i.e., cerebral circulation. If the former three factors remain constant, cervical carotid Doppler velocimetry reflects the cerebral circulation. The purpose of this report is to study whether the cervical carotid Doppler velocimetry reflects cerebral circulation or not. Parameters measured by the common carotid Doppler velocimetry were compared with cerebral blood flow (CBF) in the internal carotid arterial distribution measured by positron emission tomography (PET) in 50 patients, aged from 33 to 72 years old (mean: 56.5 +/- 8.6). These subjects were 14 with cerebral infarction, 12 with no abnormality (normal volunteers), 5 with brain tumor, 2 with normal pressure hydrocephalus, 3 with spinocerebellar degeneration, and so on. CBF was measured by the 15O-gas steady state method or H2(15)O autoradiographic method using a HEADTOME III scanner. Subsequently, pulsed Doppler flow velocimetry of the common carotid artery was performed using a RT-3600 scanner which employed a 5-MHz transducer, and systolic velocity (SV), diastolic velocity (DV), mean velocity (MV), and pulsatility index (PI) were measured. Cerebral angiography was performed in every patient except for normal volunteers, and it demonstrated no evidence of stenoocclusive lesions in the cervical carotid artery. X-ray computed tomogram (CT) was also performed in all patients. We compared CBF in the internal carotid arterial distribution with SV, DV, MV, and PI.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
604.
Nakayama A Yanagi H Minato K Tomura S 《[Nihon kōshū eisei zasshi] Japanese journal of public health》2003,50(2):118-129
PURPOSE: The purpose of this study was to forecast the demand for public health nursing visit and visiting nursing agencies' service, and to obtain basic information on public policy after the Long-term Care Insurance Project Plan starts. METHOD: 8,940 randomly sampled subjects aged 65 and over, and 7,984 aged 64 and below, were selected for the surveys and mailed the questionnaire. A total of 5,775 aged 65 and over and 4,774 aged 64 and below responded to the questionnaire. RESULTS: 2,474 (42.8%) aged 65 and over and 1,643 (34.4%) aged 64 and below knew the name 'public health nursing visit', and the service provided, 1,635 (28.3%) aged 65 and over and 1,073 (22.5%) aged 64 and below, were aware of the visiting nursing agencies' service. The percentage of those who desired to use the service was significantly higher among the respondent aged 65 and over than among those aged 64 and below. It was also significantly higher among those who had already experienced the service previously. CONCLUSION: Awareness of the service and the number of those who use the visit will increase, as those aged 64 and below become more the elderly. We therefore can expect that service demand will increase in the future. 相似文献
605.
BACKGROUND: Autocrine and paracrine growth mediated by the platelet-derived growth factor (PDGF)/PDGF receptor (PDGFR)-signaling pathway plays an important role in the progression of solid tumors. The authors assessed the effect of STI571 on the tumor growth of gastric carcinoma in combination with 5-fluorouracil (5-FU) or paclitaxel targeting the PDGF/PDGFR-signaling pathway. METHODS: In MKN-45 gastric carcinoma cells, the cytotoxic effect was evaluated by 3-(4,5 dimethiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, and the in vivo antitumor effect was evaluated in a nude mouse xenograft. Both STI571 and an antitumor drug were administered intraperitoneally. Gene expression was assessed by Western blot analysis and immunohistochemical staining. Apoptotic cell death was evaluated by the terminal deoxyuridine triphosphate-biotin nick-end labeling assay, and tumor angiogenesis was evaluated by microvessel density analysis. RESULTS: Treatment with STI571 alone was not effective in vitro, as assessed by a 50% inhibitory concentration value of 24.3 microM. Combination treatment with STI571 and 5-FU or paclitaxel enhanced the cytotoxic effect somewhat when the concentration of STI571 was increased to 10 microM. Combination treatment with STI571 and 5-FU or paclitaxel enhanced the antitumor effect of the antitumor drug significantly in vivo. The enhanced antitumor effect was associated with increased apoptotic cell death and inhibition of tumor angiogenesis. Treatment with STI571 down-regulated the expression of PDGF-BB and PDGFR-beta in tumor cells and decreased the production of phosphorylated PDGFR-beta and phosphorylated Akt. Furthermore, treatment with STI571 inhibited the expression of PDGFR-beta in stromal cells. CONCLUSIONS: STI571 was an effective chemosensitizer of antitumor drugs, such as 5-FU and paclitaxel for gastric carcinoma, targeting the PDGF/PDGFR-signaling pathway of tumor cells and stromal cells in disease progression and angiogenesis. 相似文献
606.
Kaneko M Arihiro K Takeshima Y Fujii S Inai K 《Journal of experimental therapeutics & oncology》2002,2(1):9-18
We evaluated loss of heterozygosity (LOH) and microsatellite instability (MSI) in epithelial hyperplasia of the breast by the PCR method using microsatellite markers. Seven loci of 16q, 17p, 17q, and 18q were examined in 35 lesions of epithelial hyperplasia observed in non-neoplastic breast tissue of eight breast carcinoma cases, and 29 lesions were observed within 19 fibroadenomas. These hyperplastic lesions were classified by standard criteria into three groups, namely, mild, moderate and atypical ductal hyperplasia (ADH). In the breast carcinoma cases, the frequency of loss of heterozygosity was 40% in mild, 50% in moderate, and 100% in ADH; while in the fibroadenoma cases, the frequency was 10% in mild, 27% in moderate, and 25% in ADH; total frequency of LOH was statistically higher in carcinoma cases than in fibroadenoma cases. On the other hand, the frequency of microsatellite instability was higher in fibroadenoma cases (28%) than in breast carcinoma cases (11%). Furthermore, we analyzed two cases of noninvasive ductal carcinoma arising in fibroadenoma, which had various types of hyperplasia along with carcinoma in situ, and many hyperplasias showed LOH at several of the same markers as carcinoma in situ. From those results, we speculated that LOH at these markers is an early event in mammary tumorigenesis, and some of the hyperplastic lesions with LOH have precancerous natures. 相似文献
607.
Nakajima C Uekusa Y Iwasaki M Yamaguchi N Mukai T Gao P Tomura M Ono S Tsujimura T Fujiwara H Hamaoka T 《Cancer research》2001,61(8):3399-3405
IFN-gamma-deficient (IFN-gamma-/-) mice induce potent in vitro immune responses such as anti-allo mixed lymphocyte reaction and CTL responses, whereas they often fail to exhibit in vivo immunity. Here, we investigated whether there exists a defect in tumor rejection responses and if so, which process of responses is impaired. IFN-gamma-/- and wild-type (WT) BALB/c mice were immunized with attenuated syngeneic CSA1M tumor cells. The capacity of T cells to mediate tumor protection was examined in Winn assays to assess the growth of tumor cells admixed with tumor-sensitized T cells. Splenic T cells from both groups of mice exhibited comparable levels of tumor-neutralizing activity. When portions of immunized mice were directly challenged with viable tumor cells, tumor rejection was induced only in WT mice. CD4(+) and CD8(+) T-cell infiltration were observed at the site of tumor challenge in WT mice, whereas such a T-cell infiltration did not occur in IFN-gamma-/- mice. Similarly, splenic T cells from interleukin 12-treated CSA1M-bearing IFN-gamma-/- and WT mice neutralized tumor cells at comparable efficacies in Winn assays. However, the migration of these T cells to tumor masses and the resultant interleukin 12-induced tumor regression took place in WT mice, but neither intratumoral T-cell infiltration nor tumor regression occurred in IFN-gamma-/- mice. These results indicate a critical requirement for IFN-gamma in the process of inducing T-cell migration to tumor sites rather than of generating antitumor protective T cells. 相似文献
608.
609.
1. The effect of atrial natriuretic peptide (ANP) on alpha-adrenoceptor agonist-induced renin release was examined in the de-ennervated kidney of the anaesthetized dog pretreated with propranolol (1 mg/kg, intravenous). 2. Phenylephrine (50 ng/kg per min) infused into the renal artery increased the renal secretion rate of renin (RSR) without affecting systemic blood pressure or renal blood flow. 3. Although basal RSR was unaffected, the phenylephrine-induced increase in RSR was abolished during intrarenal arterial infusion of ANP (10 ng/kg per min). 4. The results suggests that exogenously administered ANP could suppress alpha-adrenoceptor-mediated renin release in the dog. 相似文献
610.
S. Sawada M.D. H. Hashimoto S. Iijma Y. Tokano Y. Matsukawa M. Takei H. Ishikawa H. Kang K. Tomura K. Mitamura S. Hashimoto T. Obara 《Clinical rheumatology》1993,12(2):204-209
Summary We estimated the concentration of soluble IL-2R (sIL-2R) in the serum of patients with systemic lupus erythematosus (SLE) and examined the relationship between the serum levels of sIL-2R and clinical features or laboratory data. We found that elevated levels of sIL-2R were present in the serum of SLE patients with discoid rash, and sIL-2R concentrations were correlated with the soluble CD4 and soluble CD8 concentrations but not with classical serological marker, anti-DNA antibody or complement titer. 相似文献