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41.
A 62-year-old Japanese woman with RA received an eradication therapy against Helicobacter pylori in November 1999. Eight weeks later, successful eradication was confirmed by negative results for rapid urease test, pathologic findings, and a fall in anti-H. pylori IgG antibody titer. During the course, parameters for RA activity were exacerbated: C-reactive protein 1.1-4.2 mg/dL, rheumatoid arthritis precipitation antigen 2560-5120 dils., erythrocyte sedimentation rate 52-123 mm/h, and complements CH50 50 to over 60 U/mL. Lansbury index increased from 70% to 105%. Two more weeks later, the patient noticed right shoulder pain. She also complained of bilateral gonalgia two months later, and physical examination revealed increased fluid in the knee joints. Prednisolone was required to control the disease activity. The results of this case suggested that RA patients might experience a deleterious effect on the disease activity following H. pylori eradication possibly through disruption of the established oral tolerance against stress protein such as mycobacterial heat shock protein 65.  相似文献   
42.
BACKGROUND: Once food elimination is introduced, it is important to know for doctors when patients generally develop oral tolerance against eliminated food. To clarify the point, following study was conducted. METHODS: We analyzed 304 patient profiles with food allergy in our division between 1994 and 2001. The diagnosis of oral tolerance was determined by the results of food challenges or the accidental episodes of ingestion. RESULTS: By the age of 3 years old, 78% of food allergy patients with soybean, 63% of those with wheat, 60% of those with cow's milk, 51% of those with egg yolk, and 31% of those with egg white developed oral tolerance, respectively. IgE CAP RAST scores against cow's milk, egg yolk, and egg white in the patients without tolerance were significantly higher than those in the patients with tolerance. CONCLUSION: Patients developed oral tolerance firstly against soybean followed by wheat, cow's milk, egg yolk and egg white during the first 3 years of life. The specific IgE antibody levels against egg and cow's milk are important for the diagnosis of tolerance.  相似文献   
43.

Background  

The purpose of this study is to explore laypersons' attitudes toward the use of archived (existing) materials such as medical records and biological samples and to compare them with the attitudes of physicians who are involved in medical research.  相似文献   
44.
OBJECTIVE: We investigated the usefulness of skin prick test (SPT) for the diagnosis of egg white (EW) allergy in infants with atopic dermatitis who showed negative to EW CAPRAST, and followed up the EW-CAPRAST in this study. SUBJECTS AND METHODS: Data of negative SPT using Bifurcated needle (BN) were analyzed from the data of 202 atopic dermatitis infants, who had received SPT from January in 2001 to April in 2005. From the negative SPT value (average and standard deviation) positive SPT value was obtained. Among 202 cases, 89 suspected-egg allergy infants with negative IgE CAPRAST against EW at the time of first visit were recruited to examine the usefulness of SPT. Positive conversion of EW-CAPRAST was checked in 78 cases (65: egg allergy+, 13: egg allergy(-)) who had been followed up in our outpatient clinic. RESULTS: Range of negative SPT control value (mean+2SD) using BF among infants could be set as less than 2 mm for wheal and/or 5 mm for erythema. Among 89 suspected-egg allergy infants with negative EW-CAPRAST, 72 infants (80.9%) were diagnosed as egg allergy by the combination of elimination and provocation test, interestingly 39 infants (54.2%) showed positive SPT results. In the follow up study of 78 negative EW-CAPRAST cases, 47 EW-CAPRAST out of 65 egg-allergy cases turned positive later infantile period (mean EW-CAPRAST: 9.6+/-16.7 Ua/ml at 9.9+/-5.6 months old). EW-CAPRAST of 7 cases in 13 non-egg allergies also turned positive in the follow up, however EW-CAPRAST titer was relatively lower compared to that of egg allergies (1.1+/-1.5 Ua/ml at 13.3+/-2.6 months old). CONCLUSIONS: We experienced fairly number of atopic infants with negative EW-CAPRAST at the first outpatient visit, who were later diagnosed as egg allergy. In about half of these cases, SPT egg-allergy infants, three quarter of EW-CAPRAST turned positive around 10 months old. EW-CAPRAST of atopic infants without egg allergy also turned transiently and slightly positive. In the conclusions, SPT seemed to be more useful than EW-CAPRAST for the diagnosis of egg allergy in early infantile period, however provocation test should be required for the definitive diagnosis in suspected-egg allergy infants without any proof of egg-sensitization.  相似文献   
45.
CD80 and CD86 were detected in high amounts on circulating T cells in the peripheral blood of some patients with systemic lupus erythematosus (SLE), using flow cytometry and monoclonal antibodies. Patients with other connective tissue diseases did not have a high percentage of T cells expressing CD80 or CD86 in their peripheral blood. CD80 was expressed mainly on CD4 T cells, whereas CD86 was expressed on CD8 T cells, and these two populations were associated with paticular clinical features. These two molecules were expressed on different T-cell populations and might have different roles in the generation and regulation of immune responses. Since high expression of CD86 on T cells was detected much earlier than the appearance of clinical features and a high titer of anti-DNA antibody, it may be a useful parameter for predicting the flare of SLE.  相似文献   
46.
Thymic epithelial reticular cells (TER) are heterogeneous cell populations. Of 14 rat monoclonal antibodies (moAbs) raised against established cell lines of mouse thymic stromal cells (TSC), two were found to recognize TER subpopulations that exhibited distinct intrathymic distributions. MoAb B6TS-1 (IgG2a) recognized the cell-surface determinant mB6TS-1 on TSC in the subcapsular zone, cortico-medullary junction, and medulla. Double staining with antikeratin antiserum showed that, except in the cortex, the distribution of mB6TS-1 bearing cells highly corresponded with that of keratin-positive TER indicating that mB6TS-1 within the thymus was selectively expressed in a particular subpopulation of epithelial cells. Immunoelectronmicroscopy revealed clear polarity in the expression of mB6TS-1 on TER. In the subcapsular zone. TER adherent to fibrous capsule expressed mB6TS-1 on the cell surface that faced the lymphocytes. In the cortico-medullary junction, mB6TS-1 also was found on the side of the TER closely associated with the small blood vessels. The mB6TS-1-bearing cells in the medulla characteristically had cytoplasmic infoldings containing collagen fibrils and amorphous material but did not exhibit the polarity of mB6TS-1-bearing cells. The mB6TS-1-bearing TER were interconnected by desmosomes and tonofilaments, therefore, were easily distinguished from macrophages, dendritic cells, and other components of thymic stroma. In contrast, another moAb AKTS-1 (IgM) stained the keratin-positive TER localized in the subcapsular zone and cortex forming a fine meshwork but did not stain those in the medulla. MoAb B6TS-1 stained thymic nurse cells but not the central cells of thymic rosettes, whereas moAB AKTS-1 did neither. Formation of lymphoid-stromal cell complexes in vitro was not affected by either antibody.  相似文献   
47.
BACKGROUND: Manual puncture of the trophectoderm of human blastocysts with a needle before vitrification increases their survival rate, but the embryos take a long time to re-expand. This study examined whether causing human blastocysts to collapse by manual pipetting before vitrification would allow more rapid re-expansion and improve pregnancy rates. METHODS: After embryo transfer in IVF cycles, surplus embryos that developed to the expanded blastocyst stage were placed in cryoprotectant and then artificially shrunk by mechanical pipetting with a fine hand-drawn glass pipette slightly smaller in diameter than the blastocyst. The shrunken embryos were placed in a small volume of vitrification solution and plunged into liquid nitrogen on a cryotop. The blastocysts were thawed by warming and then dilution in 1 mol/l sucrose. RESULTS: Of 49 expanded vitrified blastocysts, 48 (98%) re-expanded within 3 h after warming. Following transfer (48 blastocysts in 28 cycles), 14 women (50%) became clinically pregnant, and the implantation rate was 33% (16/48). Eight healthy babies have been born in six deliveries, and the other eight pregnancies are ongoing. To date, there have been no spontaneous abortions. CONCLUSIONS: The results suggest that artificial shrinkage with pipetting is a simple and effective technique to assist successful cryopreservation of expanded blastocysts by vitrification.  相似文献   
48.
Human bone marrow-derived mesenchymal cells contain mesenchymal stem cells (MSCs), which are well known for their osteo/chondrogenic potential and can be used for bone reconstruction. This article reports the viability of cryopreserved human mesenchymal cells and a comparison of the osteogenic potential between noncryopreserved and cryopreserved human mesenchymal cells with MSC-like characteristics, derived from the bone marrow of 28 subjects. The viability of cryopreserved mesenchymal cells was approximately 90% regardless of the storage term (0.3 to 37 months). It is clear by fluorescence-activated cell sorter analysis that the cell surface antigens of both noncryopreserved and cryopreserved mesenchymal cells were negative for hematopoietic cell markers such as CD14, CD34, CD45, and HLA-DR but positive for mesenchymal characteristics such as CD29 and CD105. To monitor the osteogenic potential of the cells, such as alkaline phosphatase (ALP) activity and in vitro mineralization, a subculture was conducted in the presence of dexamethasone, ascorbic acid, and glycerophosphate. No difference in osteogenic potential was found between cells with or without cryopreservation treatment. In addition, cells undergoing long-term cryopreservation (about 3 years) maintained high osteogenic potential. In conclusion, cryopreserved as well as noncryopreserved human mesenchymal cells could be applied for bone regeneration in orthopedics.  相似文献   
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