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991.
992.
We report a 27-year-old case of juvenile idiopathic arthritis (JIA) having been stopped infliximab during pregnancy. She was safely treated by infliximab therapy with premedications for preventing infusin reactions after her delivery, and then improved in the same manner as when she had been treated with infliximab therapy before pregnancy. As a result, it remains unclear whether or not we can use infliximab to control disease activities during pregnancy. In addition, it is also important to clarify whether or not premedications should be used when resuming infliximab treatment in such patients after pregnancy. These problems still remain controversial. More definitive data are needed in order to allow rheumatologists to better select the optimal TNF-alpha inhibitor therapy when treating pregnant JIA patients.  相似文献   
993.
To investigate the relationship between plasma levels and coronary vasodilation after administration of isosorbide dinitrate (ISDN), the plasma concentration and diarneters of six segments of the left coronary artery were measured before and after sublingual (SL) ISDN (5 mg) and left intracoronary (IC) administration of ISDN (3 mg) in 12 patients. After SL-ISDN, the systolic aortic pressure decreased with no significant concomitant changes in heart rate or diastolic aortic pressure. After IC-ISDN, all hemodynamic parameters showed significant changes, and these were greater after IC-ISDN than those after SL-ISDN. The individual mean vasodilation of six segments induced by SL- and IC-ISDN, were 23± 9 and 35± 11% (p<0.01), respectively. Before SL-ISDN, ISDN was not detected in plasma. After SL- and IC-ISDN, however, the plasma values of the ISDN were 36.1± 53.3 and 101.5± 90.0 ng/ml (p<0.01), respectively. Thus, both coronary vasodilative responses and plasma ISDN levels after IC-ISDN were significantly greater than those after SL-ISDN. However, neither the individual mean coronary vasodilation nor the hemodynamic changes correlated significantly with plasma ISDN levels. Consequently, with administration of the same dose, the coronary vasodilative response to ISDN did not correlate with plasma levels. Furthermore, IC-ISDN dilates coronary arteries more effectively than SL-ISDN.  相似文献   
994.
A 54-year-old Japanese woman was diagnosed with rheumatoid arthritis (RA) in 1995 on the basis of symmetric effusive polyarthritis, morning stiffness, and strongly positive rheumatoid factor. She had received low-dose prednisolone, indomethacin, methotrexate (MTX), and cyclophosphamide (CPA), at least, over 4 years before the current admission and showed partial improvement of polyarthralgia. In November 2002, she suddenly developed thrombocytopenia (platelet count was 0.3×104 mm–3) with purpura and was diagnosed with immune thrombocytopenic purpura (ITP). As she had refractory ITP, the administration of pulsed high-dose dexamethasone (DEX) therapy was started, resulting in the complete remission of ITP. The present paper reports that pulsed high-dose DEX therapy was useful for the treatment of refractory ITP associated with RA.  相似文献   
995.
OBJECTIVES: We assessed the effect of administration time for fasudil treatment of the stunned myocardium in 40 anesthetized open chest swine. MATERIALS AND METHODS: All swine were subjected to 12 min ischemia followed by reperfusion to generate stunned myocardium. Group A (n = 11) received saline in place of fasudil both before ischemia and after reperfusion. Group B (n = 10) received 30 min intravenous fasudil at a rate of 13 mug/kg/min starting 45 min before ischemia and received saline after reperfusion. Groups C (n = 10) and D (n = 9) received saline before ischemia, and received fasudil at a rate of 13 mug kg(-1) min(-1) starting just before reperfusion in group C and 30 min after reperfusion in group D. In both groups, treatment lasted 30 min. Myocardial contractility was assessed by percent segment shortening (%SS). RESULTS AND DISCUSSION: Three swine in group A, 2 swine in each of groups B and C, and one swine in group D had ventricular fibrillation or tachycardia after reperfusion and were excluded from further analysis. The changes of %SS from baseline at 90 min after reperfusion in groups B and C were 68 +/- 8% and 75 +/- 8%, respectively, which were significantly higher than in group A or D (47 +/- 10% or 43 +/- 8%). CONCLUSION: We conclude that fasudil administered before ischemia or just after reperfusion, but not 30 min after reperfusion, protects the stunned myocardium.  相似文献   
996.

Background

Several methods have been developed to detect allergen-specific IgE in sera. The passive IgE sensitization assay using human IgE receptor-expressing rat cell line RBL-2H3 is a powerful tool to detect biologically active allergen-specific IgE in serum samples. However, one disadvantage is that RBL-2H3 cells are vulnerable to high concentrations of human sera. Only a few human cultured cell lines are easily applicable to the passive IgE sensitization assay. However, the use of human induced pluripotent stem cells (iPSCs) to generate human mast cells (MCs) has not yet been reported.

Methods

The nuclear factor-kappa B (NF-κB)-responsive luciferase reporter gene was stably introduced into a human iPSC line 201B7, and the transfectants were induced to differentiate into MCs (iPSC-MCs). The iPSC-MCs were sensitized overnight with sera from subjects who were allergic to cedar pollen, ragweed pollen, mites, or house dust, and then stimulated with an extract of corresponding allergens. Activation of iPSC-MCs was evaluated by β-hexosaminidase release, histamine release, or luciferase intensity.

Results

iPSCs-MCs stably expressed high-affinity IgE receptor and functionally responded to various allergens when sensitized with human sera from relevant allergic subjects. This passive IgE sensitization system, which we termed the induced mast cell activation test (iMAT), worked well even with undiluted human sera.

Conclusions

iMAT may serve as a novel determining system for IgE/allergens in the clinical and research settings.  相似文献   
997.

Background

Most of the patients develop food allergy early in life. The factors related to parental immune condition might be one of the conceivable causes.

Methods

We reported murine models of food allergy and oral OVA tolerance. To investigate the influence of parental immune condition on infant food allergy, female and male mice with food allergy or oral tolerance were mated with each other.

Results

Food allergy was suppressed by decreased IgE production in the offspring of mice with food allergy. On the contrary, anaphylaxis for OVA was induced in the offspring of mice with oral tolerance. The suppression of food allergy being dependent on a maternal factor was revealed in the offspring after cross-mating mice with food allergy and oral tolerance. Because OVA-specific IgG, presumed to be from the allergic mother, was detected in the serum of naïve infants from mothers allergic to food, we assumed that the suppression was dependent on a specific IgG. The serum IgG purified by a G-protein column was administered before OVA sensitization in the food allergy model, and OVA-specific IgE production was found to be diminished in the administered mice. However, OVA-specific monoclonal IgG1 and IgG2a administration could not suppress food allergy. Because we detected OVA-IgG immune complex in the serum of mothers allergic to food, it might be a cause of maternal immune suppression.

Conclusions

We demonstrated that maternal specific IgG conjugated food antigen is an important factor related to the development of food allergy and acquiring tolerance.  相似文献   
998.
Exocrine pancreatic function in the early period after pancreatoduodenectomy was investigated. The effects of preoperative pancreatic duct obstruction on exocrine pancreatic function were also investigated. The volume of pancreatic juice and its amylase activity were investigated in 39 patients who underwent pancreatoduodenectomy (including pylorus-preserving pancreatoduodenectomy). TheN-benzoyl-l-tyrosyl-p-aminobenzoic acid (BT-PABA) test was performed on 23 of 39 patients about 40 days after pancreatoduodenectomy. The exocrine pancreatic function was inhibited three to eight days after pancreatoduodenectomy (amylase activity: 23,700±4300 IU/day), and recovered on days 9–15 (48,000±8400 IU/day) in patients with a normal main pancreatic duct. In patients with pancreatic duct obstruction, the exocrine pancreatic function was almost eliminated (amylase activity: 440±260 IU/day) and BT-PABA test results were low (45±17%). In patients with narrowed pancreatic duct, amylase secretion was significantly inhibited even in patients with a normal number of acinar cells. There was a good positive correlation (Spearman's rank correlation coefficient,rs=0.715,P<0.01) between amylase secretion and BT-PABA test. Amylase secretion more than 10,000 IU/day is essential for a normal BT-PABA test and normal digestive function. The inhibited digestive function in patients with pancreatic duct obstruction may be due to the decreased number of acinar cells and the inhibition of exocrine pancreatic function.  相似文献   
999.
Inactivation of the tumor suppressor p53 by missense mutations is the most frequent genetic alteration in human cancers. The common missense mutations in the TP53 gene disrupt the ability of p53 to bind to DNA and consequently to transactivate downstream genes. However, it is still not fully understood how a large number of the remaining mutations affect p53 structure and function. Here, we used a comprehensive site-directed mutagenesis technique and a yeast-based functional assay to construct, express, and evaluate 2,314 p53 mutants representing all possible amino acid substitutions caused by a point mutation throughout the protein (5.9 substitutions per residue), and correlated p53 function with structure- and tumor-derived mutations. This high-resolution mutation analysis allows evaluation of previous predictions and hypotheses through interrelation of function, structure and mutation.  相似文献   
1000.
Early-onset sarcoidosis (EOS) and inheritable Blau syndrome (BS) share characteristic clinical features of juvenile-onset systemic granulomatosis syndrome that mainly affects skin, joints, and eyes. However, no direct evidence has been shown for the possible common origin of these 2 diseases. Recent discovery of CARD15 mutations in BS families encouraged us to investigate similar CARD15 mutations in EOS patients. Among 10 EOS cases retrospectively collected in Japan, heterozygous missense mutations were found in 9 cases; 4 showed a 1000C>T (R334W in amino acid change) that has been reported in BS, 4 showed novel 1487A>T (H496L), 1538T>C (M513T), 1813A>C (T605P), and 2010C>A (N670K), and 1 case showed double 1146C>G (D382E)/1834G>A (A612T) mutations on different alleles. All 6 of these variants of CARD15 showed increased basal nuclear factor (NF)-kappaB activity. These findings indicate that the majority of EOS and BS cases share the common genetic etiology of CARD15 mutations that cause constitutive NF-kappaB activation.  相似文献   
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