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71.
72.
Antibody penetration of viable cells and interaction with intracellular antigens may have major consequences for immunopathological processes in connective tissue diseases. We have reported previously that antibody can penetrate viable human lymphocytes. To assess further the role of antinuclear antibodies in this process, peripheral blood lymphocytes (PBMC) were incubated with FITC-conjugated IgG fractions from sera containing anti-RNP (anti-RNP IgG), Ro(SS-A), La(SS-B) and dsDNA antibodies and control sera for 24 h. Using crystal violet to quench cell surface staining, intracellular fluorescence of viable lymphocytes was quantified on the flow cytometer. It was noted that anti-RNP IgG entered 46.4 +/- 7.2% of lymphocytes which was significantly higher than anti-Ro(SS-A) (29.9 +/- 4.1%, P less than 0.05), La(SS-B) (22.0 +/- 7.5%, P less than 0.01) IgG and control IgG (28.8 +/- 2.1%, P less than 0.05) and not statistically different from anti-dsDNA IgG (32.6 +/- 14.3%). Inhibition experiments showed that the increased number of cells penetrated by anti-RNP IgG was a specific process. Time-course studies showed that anti-RNP IgG entry into cells was different from pooled control IgG. With anti-RNP IgG, positive-staining lymphocytes gradually increased in number from 12 to 24 h incubation, whilst with pooled control IgG, the peak was reached within 5 min. Dual staining experiments suggested that whereas both anti-RNP IgG and pooled control IgG entered B and NK cells, anti-RNP IgG also entered T cells. Using IgG F(ab')2 and Fc fragments from either anti-RNP IgG or pooled control IgG to compete with their FITC-conjugated counterparts indicated that the entry of anti-RNP IgG into-viable cells appeared to involve both F(ab')2 and Fc fragments, and pooled control IgG depended exclusively on the Fc portion of IgG. Further investigation by incubating anti-RNP IgG with 35S-methionine-labelled monocyte-depleted PBMC (MD-PBMC) suggested that anti-RNP IgG might react with the corresponding antigens either on the cell surface or within the cytoplasm.  相似文献   
73.
BACKGROUND: Inhaled corticosteroids (ICS) are recommended therapy for persistent asthma, although side effects can limit appropriate use. Ciclesonide, a novel ICS, is activated in the lung, thereby reducing systemic activity and side effects. This 12-week, double-blind, randomized, parallel-group, placebo-controlled study evaluated the efficacy and safety of ciclesonide in adults with persistent asthma. METHODS: After a 2-week baseline period in which current ICS treatment was continued, 329 patients were randomized to receive ciclesonide 160 microg (n = 107) or 640 microg (n = 112) (ex-actuator doses, equivalent to 200 and 800 microg ex-valve, respectively), or placebo (n = 110) once daily in the morning. Efficacy was monitored by asthma symptom scores, rescue medication use, morning and evening peak expiratory flow (PEF) measurements, spirometry, and probability of study completion without experiencing lack of efficacy. RESULTS: Morning PEF remained stable with either ciclesonide dose but decreased with placebo; the differences were significant (P < 0.0001) for both ciclesonide doses vs placebo. The forced expiratory volume in 1 s and forced vital capacity decreased significantly with placebo (P < 0.005), but were unchanged with ciclesonide. Lack of efficacy was significantly greater for patients switched to placebo (63%) than it was for those treated with ciclesonide 160 microg (30%) (P < 0.0001 vs placebo) or ciclesonide 640 microg (31%) (P < 0.0001 vs placebo). There were no significant differences between the two tested doses of ciclesonide with respect to efficacy and safety. Serum and 24-h urine cortisol were unaffected by ciclesonide treatment. Both doses of ciclesonide were well tolerated with no cases of oral candidiasis. CONCLUSION: Ciclesonide (160 or 640 microg) once daily in the morning effectively maintains asthma control, does not affect cortisol levels, and has an adverse event profile comparable with placebo in adults with primarily mild to moderate asthma.  相似文献   
74.
Linkage analysis was carried out on 20 unselected UK families segregating for adenomatous polyposis coli (APC) using four closely linked DNA probes. Significant lod scores were obtained between APC and three markers: pi 227 (D5S37) theta = 0.16; C11p11 (D5S71) theta = 0.10; and YN5.48 (D5S81) theta = 0.00. The fourth, ECB27 (D5S98), gave low lod scores. The APC gene showed linkage with at least one of the probes used in all families, which is in agreement with previous publications. Combined lod scores are now sufficiently high to allow the use of these probes in presymptomatic diagnosis. Despite the fact that 61% of persons at risk were informative for at least one DNA marker, only 15% were informative with flanking probes. One prenatal diagnosis was performed where the initial request had been for sterilisation.  相似文献   
75.
A current generated by the Na-activated K channel has been identified in whole cell currents recorded from isolated guinea-pig ventricular myocytes. A partial activation of this current can be achieved near to the physiological range of intracellular sodium concentration [( Na+]i) when it contributes significantly to the global outward current. The decline of the Na-activated K current, the lengthening of the action potential duration and the recovery of [Na+]i occur with a similar time course during recovery from Na loading.  相似文献   
76.
First trimester termination of pregnancy was successfully inducedin ten patients with RU 38486 followed 2 days later by a prostaglandin(Gemeprost) pessary. Human chorionic gonadotrophin (HCG) valuesremained unaltered until after the abortion. The levels of placentalprotein 12 (PP12) showed an immediate and significant fall followingRU 38486, then rose to values substantially higher than thoseat the initial visit after 2 days. These findings show thatRU 38486 has a direct inhibitory effect on tissues producingPP12 and confirm the progesterone dependency of this protein  相似文献   
77.
PROBLEM: Neonatal estradiol injections in mice lead to follicular cystic ovaries that are similar to ovaries in patients with polycystic ovarian syndrome (PCOS). The present study examined ovarian cytokine production following neonatal estradiol injection. METHOD OF STUDY: Female (C3H,HeJ x 129/HeJ)F1 mice were injected daily with 20 microg 17beta-estradiol from 0-3 days postpartum. At intervals, animals were sacrificed to determine ovarian architecture, circulating levels of estradiol, ovarian and peritoneal macrophage cytokine production, and ovarian P450 aromatase enzyme mRNA levels. RESULTS: Similar to PCOS, our results show that neonatally estradiol-injected mice have lower levels of circulating estrogen that are correlated with decreased mRNA levels of P450 aromatase enzyme. Our data also show that follicular cystic ovaries have increased tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 production. This increase in TNF-alpha and IL-6 production is also observed in peritoneal macrophages of estradiol-injected mice. CONCLUSION: The present study showed that neonatal estrogen injection in mice has an overall systemic effect on cytokine production. We speculate that increased cytokine production may alter certain important steps in follicular maturation, ultimately contributing to ovarian dysfunction.  相似文献   
78.
BACKGROUND: Peanut allergy is an important health problem in the United States, affecting approximately 0.6% of children. Inadvertent exposure to peanut is a risk factor for life-threatening food-induced anaphylaxis. OBJECTIVE: The purpose of this investigation was to develop an immunoassay for a major peanut allergen, Ara h 1, to detect peanut allergen in foods so that the risk of inadvertent exposure can be reduced. METHODS: A specific 2-site monoclonal antibody-based ELISA was developed to measure Ara h 1 in foods. The sensitivity of the assay was 30 ng/mL. Ara h 1 was measured in foods (n = 83) with or without peanut and in experiments to optimize allergen yield and to determine peanut contamination in spiked foods. RESULTS: Ara h 1 levels in food products ranged from less than 0.1 microg/g to 500 microg/g. Ara h 1 measured in ng/mL was transformed to microg/g for food products. Peanut butter contained the highest amounts of Ara h 1. Peanut extracts contained from 0.5 to 15 mg Ara h 1/g of peanut depending on the extraction conditions. Optimal extraction of Ara h 1 was obtained by using phosphate buffer with 1 mol/L NaCl and Tween at 60 degrees C. Ara h 1 was not always detected in presence of chocolate under the extraction conditions tested. Spiking experiments showed that the assay could detect approximately 0.1% Ara h 1 contamination of food with ground peanut. There was an excellent correlation between Ara h 1 levels and peanut content measured by using a commercial polyclonal antibody-based ELISA (r = 93, n = 31, P <.001). CONCLUSION: A new sensitive and specific monoclonal antibody-based ELISA was used to monitor Ara h 1 content in food products. This assay should be useful for monitoring peanut contamination in the food manufacturing and processing industry and in developing thresholds for sensitization or allergic reaction in persons with peanut allergy.  相似文献   
79.
BACKGROUND: H(1)-antihistamines are widely used for symptom relief in allergic disorders in infants and children; however, there are few prospective, randomized, double-blind, controlled studies of these medications in young children, and to date, no such studies have been conducted in infants. OBJECTIVE: This prospective, randomized, parallel-group, double-blind, placebo-controlled study was designed to evaluate the safety of the H(1)-antihistamine cetirizine, particularly with regard to central nervous system and cardiac effects, in infants age 6 to 11 months, inclusive. METHODS: Infants who met the entry criteria for age and had a history of treatment with an H(1)-antihistamine for an allergic or other disorder were randomized to receive 0.25 mg/kg cetirizine orally or matching placebo twice daily orally for 1 week. RESULTS: The mean daily dose in cetirizine-treated infants was 4.5 +/- 0.7 mg (SD). No differences in all-cause or treatment-related adverse events were observed between the cetirizine- and placebo-treated groups. A trend was observed toward fewer adverse events and sleep-related disturbances in the cetirizine group compared with the placebo group. No prolongation in the linear corrected QT interval was observed in cetirizine-treated infants compared with either baseline values or with values in placebo-treated infants. CONCLUSIONS: We have documented the safety of cetirizine in this short-term investigation, the first randomized, double-blind, placebo-controlled study of any H(1)-antihistamine in infants. Additional prospective, randomized, double-blind, placebo-controlled, long-term studies of cetirizine and other H(1)-antihistamines are needed in this population.  相似文献   
80.
Background:  Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods:  Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results:  Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions:  HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects.  相似文献   
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