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51.
BACKGROUND: Atopic dermatitis (AD) can be exacerbated or induced in genetically predisposed individuals by psychological stress, which causes the release of substance P (SP). Therefore, SP may play an etiological role in the mechanisms underlying AD. METHODS: Changes in the number of mast cells and SP-containing mast cells in lesional skin, and the serum concentrations of SP and IgE during the development of AD-like disease up to 8 weeks after the start of picryl chloride (PiCl) induction in NC/Nga mice were examined. RESULTS: Clinical signs and symptoms seen in PiCl-treated NC/Nga mice as a model of AD-like disease began with erythema and haemorrhage, followed by oedema, superficial erosion, deep excoriation, scaling and dryness of the skin, as well as retarded growth, and the changes were exacerbated with an increase in the number of PiCl applications. An increase in the number of mast cells and eosinophil infiltration was observed in the lesional skin. The increase in SP-positive mast cells in the dermis in this model was significant from 1 week after the start of induction treatment, compared with intact mice, and SP-positive nerve fibres were observed in the dermis. CONCLUSION: SP is a crucial mediator of both dermatitis and scratching behaviour in this model.  相似文献   
52.
Phytosterol oxidation products (oxyphytosterols) are formed during the processing and storage of foods. However, it is unknown whether oxyphytosterols affect human health. To address these issues, we prepared beta-sitosterol and campesterol oxides, evaluated their lymphatic absorption in rats, and examined the effect of an oxyphytosterol diet on atherosclerosis in apolipoprotein (apo) E-deficient mice. The lymphatic absorption of cholesterol and 6 oxyphytosterols (7alpha-hydroxy, 7beta-hydroxy, beta-epoxy, alpha-epoxy, dihydroxy, and 7-keto) of beta-sitosterol or campesterol was assessed in thoracic duct-cannulated rats fed an AIN-93G-based diet containing 2.5 g of cholesterol, oxyphytosterols, or intact phytosterols per kg. Lymphatic recoveries (on a mass basis) of oxycampesterols (15.9 +/- 2.8%, n = 10) and oxysitosterols (9.12 +/- 1.77%, n = 10) were higher than for campesterol (5.47 +/- 1.02%, n = 12, P < 0.05) and beta-sitosterol (2.16 +/- 0.37%, n = 12, P < 0.05), but lower than for cholesterol (37.3 +/- 8.3%, n = 6, P < 0.05). Apo E-deficient mice were fed an AIN-93G-based diet containing 0.2 g oxyphytosterols or intact phytosterols per kg for 9 wk. Diet-derived oxyphytosterols accumulated in the serum, liver, and aorta. Furthermore, the oxyphytosterol diet increased oxycholesterol in the serum compared to the phytosterol diet. However, there was no significant difference between the 2 groups in the serum and aortic cholesterol concentration, the lesion area in the aortic root, or 8-iso-prostaglandin F2alpha concentration in the urine. These results indicate that exogenous oxyphytosterols are well-absorbed and accumulate in the body, but do not promote the development of atherosclerosis in apo E-deficient mice.  相似文献   
53.
The effect of a blocking-antibody specific for lymphocyte function-associated antigen-1 (LFA-1) was studied in an atopic-like dermatitis model, which was induced by the repeated application of picrylchloride in NC/Nga mice. Prophylactic treatment with anti-LFA-1 monoclonal antibody (mAb), not therapeutic treatment, significantly inhibited the skin severity score and the acanthosis with ulceration and infiltration of mast cells. Furthermore, the serum immunoglobulin E levels and cytokine production (interleukin-4 and interferon-gamma) by splenocytes stimulated with anti-CD3 antibody were also inhibited by treatment with anti-LFA-1 mAb. Our results suggest that LFA-1 plays an important role in the induction phase of the atopic-like dermatitis model.  相似文献   
54.
BACKGROUND AND OBJECTIVE: In a prior study, we showed no significant relationship between intake and balance of magnesium (Mg). Subsequent further investigation disclosed that intakes of both Ca and P were positively correlated with their respective balances, whereas intake of Mg did not show any significant correlation with Mg balance. In this paper, we show positive correlations between intake of Mg and balances of both Ca and P. METHODS AND RESULTS: Using these correlations, the mean value and upper limit of the 95% confidence interval (from the regression equation between Mg intake and either the balances of Ca or that of P, when each balance is equal to zero) were 4.584 and 4.802 (against Ca balance), 4.554 and 4.785 (against P balance) mg/kg BW/d, respectively. Balances of Mg and Ca correlated with each other.  相似文献   
55.
BACKGROUND: ACD-A solution containing sodium citrate and citric acid is used as an anticoagulant agent during peripheral blood progenitor cell (PBPC) harvesting, and in rare cases can cause fatal citrate intoxication. The aim of this study was to establish effective methods for stabilizing ionized calcium (ICa) levels during PBPC harvesting. STUDY DESIGN AND METHODS: ICa was measured during 46 apheresis procedures conducted in 26 patients. Four patients in four procedures were infused with calcium gluconate solution before PBPC harvesting; three patients in six procedures were infused with calcium gluconate when symptoms of citrate intoxication appeared; and four patients in five procedures received a continuous infusion. Five patients in five procedures took an isotonic sports drink containing calcium when hypocalcemic symptoms appeared. The ICa level, blood pressure, and pulse rate were measured. RESULTS: ICa declined rapidly from the preapheresis level of 1.081(+/-0.092) mM to 0.937(+/-0.081) mM (13.3%, p < 0.0001) 10 minutes after the start of apheresis and continued to decline until the completion of the procedure. When patients received a continuous infusion of calcium during apheresis, ICa was relatively stabilized. ICa significantly rose (6.1 +/- 3.6%, p < 0.02) within 2 to 5 minutes after oral intake of an isotonic sports drink containing calcium and was maintained within normal range for 31 to 55 minutes. CONCLUSION: An isotonic sports drink containing calcium has a quick stabilizing and a longer maintenance effect on ICa. Thus, we recommend the intake of an isotonic sports drink containing calcium as the easiest and best method for preventing hypocalcemia during apheresis.  相似文献   
56.
The aim of this study was to investigate the clinical utility of sequential imaging of hepatocellular carcinoma (HCC) by contrast-enhanced power Doppler ultrasonograpy (CE-PDUS) to differentiate hepatocellular carcinoma from adenomatous hyperplasia (AH) and regenerated nodule (RN) and to predict the degree of differentiation of HCC. Fifty-one patients with 62 hepatic lesions including 33 moderately and poorly differentiated HCCs, 19 well-differentiated HCCs, seven AHs and three large RNs were examined by CE-PDUS. The imaging patterns during early arterial phase (tumor vessel image), late vascular phase (tumor perfusion image) and post-vascular phase (liver perfusion image) were classified as diffuse, basket, peripheral, central and no enhancement; as whole tumor, partial tumor and no enhancement; as whole tumor, partial tumor and no defect, respectively. The diffuse pattern in the tumor vessel image, the whole enhancement pattern in the tumor perfusion image and the whole defect pattern in the liver perfusion image were observed in moderately and poorly differentiated HCCs only. The basket pattern in the tumor vessel image and the partial defect pattern in the tumor perfusion image were observed in HCCs only. All AH/RNs showed no defect pattern in the liver perfusion image. The sequential imaging of HCC during early arterial, late vascular and post-vascular phases by CE-PDUS is clinically useful to differentiate HCC from AH/RN and to predict the degree of differentiation of HCC.  相似文献   
57.
BACKGROUND: Tissue factor (TF) expression is induced on macrophages and endothelial cells during the immune response. We designed an antisense (AS) phosphorothioate oligodeoxynucleotide (ODN) to specifically inhibit the expression of rat TF to study the effects of the AS ODN on renal ischemia-reperfusion injury in the rat. METHOD: AS-1 ODN for TF was delivered intravenously to inhibit the expression of TF in endothelial cells. After 8 hr, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 min of ischemia, and rats were killed at 0, 1.5, 5, 12, and 24 hr after reperfusion. TF expression was analyzed by immunohistochemical staining using monoclonal antibody. RESULTS: In the untreated ischemic group, 0 of 20 rats survived beyond day 3. However, treatment with AS-1/TF led to 12 of 20 rats surviving beyond day 4. TF was detected on distal tubular epithelial cells, endothelial cells, and blood vessels but not on necrotic and proximal tubular epithelial cells. The necrotic area extended and encompassed nearly all of the ischemic kidney within 12 hr after reperfusion. The necrotic area and the grade of TF staining were more significantly reduced in the AS-1/TF-treated group than in the control group. Furthermore, fluorescein isothiocyanate-labeled AS-1/TF was significantly intense in tubular epithelial cells 8 hr after intravenous administration. CONCLUSIONS: The results indicate that AS-1/TF inhibited the ischemia-reperfusion injury of the kidney. Microcirculatory incompetence resulting from microthrombus may cause the formation and development of necrosis.  相似文献   
58.
We present a case of idiopathic right vocal fold paralysis which resolved completely 18 months after onset. Instead of using surgery to improve the hoarseness of our patient, our experience suggested that speech therapy might be effective. Although the voice can be improved by overadduction of the healthy vocal fold, as surgery is irreversible it is better to wait for 18 months after onset in case spontaneous recovery occurs. During this period, one should of course continue to investigate the origin of the paralysis.  相似文献   
59.
The Long-Evans Cinnamon (LEC) rat is a mutant strain of rats that accumulate copper (Cu) in the liver in much the same way as individuals who suffer from Wilson's disease (WD) and has been suggested as a model for this disease. Lipid peroxidation (LPO) is considered to be involved in the toxic action of Cu in the livers of LEC rats. We investigated the mechanism of LPO in the livers of LEC rats showing apparent signs of hepatitis. Several-fold higher LPO levels were observed in post-mitochondrial supernatant (S-9) fraction of livers from hepatitic LEC rats than in those from Wistar rats. To mimic living cells, we introduced NADPH-generating system (NADPH-gs) into the S-9 incubation system. Thus was ensured a constant supply of NADPH to vital enzymes that may be directly or indirectly involved in the generation and/or elimination of reactive oxygen species (ROSs), such as glutathione reductase (GSSG-R), which require NADPH for their reactions. The levels of LPO in liver S-9 from hepatitic LEC rats were further increased by incubating liver S-9 at 37 °C in the presence of NADPH-gs. This increase was inhibited by EDTA, butylated hydroxytoluene (BHT), and catalase (CAT), suggesting that some metal, most likely the accumulated Cu, and ROSs derived from hydrogen peroxide (H2O2) are involved in the increased levels of LPO in the livers of hepatitic LEC rats. The requirement of NADPH-gs for enhanced LPO in the livers of hepatitic LEC rats indicates the consumption of NADPH during reactions leading to LPO. It is known that H2O2, and consequently hydroxyl radical are generated during Cu–catalyzed glutathione (GSH) oxidation. The cyclic regeneration of GSH from GSSG by NADPH-dependent GSSG-R in the presence of NADPH-gs may cause sustained generation of hydroxyl radical in the presence of excess free Cu. The generation of H2O2 in S-9 fraction of livers from hepatitic LEC rats was observed to be significantly higher than that in S-9 fraction of livers from non-hepatitic LEC rats and Wistar rats. Moreover, in addition to the reported decrease in glutathione peroxidase (GPX) activity, we found that CAT activity was markedly decreased in LEC rats with hepatitis. The increased generation of H2O2 with reduced activities of GPX and CAT may result in cellular accumulation of H2O2 in the liver of hepatitic LEC rats. Taken altogether, it is suggested that the accumulated H2O2 undergoes the Fenton-type reaction with also accumulated free Cu, thus generating hydroxyl radical in the livers of hepatitic LEC rats and increasing LPO levels in these animals. Received: 20 April 1999 / Accepted: 2 September 1999  相似文献   
60.

Purpose  

We attempted clinical application of a plastic blade, which is a novel cryopreservation device, for vitrification of human embryos and blastocysts.  相似文献   
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