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21.
BACKGROUND: Cupressaceae is a family of plants resistant to airborne contamination, and its pollen is the main cause of winter allergic respiratory diseases, especially in North America, Japan, and Mediterranean countries. Recently, a major allergen from Cupressus arizonica pollen grains, Cup a 3, was cloned and expressed. OBJECTIVE: To study the effects of air pollution on the expression of Cup a 3, a thaumatinlike protein, in C. arizonica pollen grains using a combination of transmission electron microscopy and immunocytochemical techniques. METHODS: Observations were made in mature and hydrated C. arizonica pollen grains from various regions in Spain with different degrees of air pollution. Specimens were fixed using freezing protocols, and ultrathin sections were incubated with anti-rCup a 3 rabbit polyclonal antibodies. RESULTS: Labeling of Cup a 3 was detected in mature and hydrated C. arizonica pollen grains. It was more intense in pollen from polluted air regions, and abundant gold particles were observed as they were released through the pollen grain walls. Furthermore, gold particles remained abundant in the pollen cytoplasm. The labeling was noticeably lower in pollen grains from unpolluted air regions. CONCLUSIONS: Cup a 3 is present in the cytoplasm and walls of cypress pollen grains during the air dispersion and hydration stages. The abundance of Cup a 3 in pollen grains under polluted air conditions indicates that these cypresses intensify their activity as a defense from environmental pollution, thus strengthening their allergenicity.  相似文献   
22.
Lymphocyte Stimulation   总被引:1,自引:0,他引:1  
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23.
A 52-year-old man presented with heart failure of 1 month duration. He had undergone aortic valve and root replacement 30 months before admission. A continuous murmur was heard in the second intercostal space at the parasternal border. Aortography showed a pseudoaneurysm surrounding the aorta, whereas color Doppler study revealed flow from the central aorta to the pseudoaneurysm and flow from the pseudoaneurysm to the pulmonary artery trunk through a fistulous communication between them. Thus, fistulous communication with pulmonary artery causing heart failure is a complication of pseudoaneurysm after aortic and root replacement, which can be diagnosed clinically and echocardiographically.  相似文献   
24.
Intestinal dendritic cells increase T cell expression of alpha4beta7 integrin   总被引:10,自引:0,他引:10  
The integrin alpha4beta7 binds to MAdCAM-1 and contributes to homing of lymphocytes to gut and other mucosal tissues. In humans, the alpha4beta7(hi) subset of circulating memory cells appears to have been primed in mucosal tissues. The factors that determine whether alpha4beta7(lo) naive cells become alpha4beta(hi) or alpha4beta7(-) cells upon differentiation are poorly understood but could include an influence of the activating antigen-presenting cell. To address this point, the induction of alpha4beta7 following activation of mouse cells with the APC-dependent stimulus soluble anti-CD3 has been examined. Almost all mouse T cells freshly isolated from mesenteric lymph nodes (MLN) and peripheral (PLN; axillary, brachial and inguinal) lymph nodes stained only weakly for alpha4beta7 but a subpopulation became alpha4beta7(hi) upon activation with anti-CD3 in a cell cycle- and accessory cell-dependent manner. A small proportion (approximately 1.5 %) of the starting cells gave rise to alpha4beta7(hi) cells after culture. A higher proportion of alpha4beta7(hi) cells were generated in MLN than PLN cultures. Peyer's patch cultures gave intermediate values. In crossover experiments, MLN dendritic cells (DC) induced higher proportions and numbers of alpha4beta7(hi) cells than PLN DC irrespective of the source of T cells. Therefore, in addition to their other immunoregulatory roles, DC have the potential to shape immune responses by influencing the homing of the lymphocytes they activate.  相似文献   
25.
Nineteen patients that had developed hypertrophic scars subsequent to thermal injury were typed for HLA class II allogenotypes with the restriction fragment length polymorphism technique. A significant association was found with DR beta 16 (pc = 1.45 x 10(-4); relative risk = 12.25). This finding adds evidence to other data suggesting that immunologic phenomena are involved in pathologic scarring. Moreover, the results presented here have allowed an identification of a genetically determined risk factor for hypertrophic scar formation located in the HLA region.  相似文献   
26.
Occurrence of renal involvement in Rheumatoid arthritis is uncommon; when present it has been attributed to amyloid or secondary effects of drugs. Nevertheless, recent observations seem to indicate the existence of primary renal lesions associated with the disease. The purpose of this paper is to review the data suggesting that the kidney can be directly involved in Rheumatoid arthritis. The main points of interest are the occurrence of glomerulonephritis and/or amyloidosis, the presence of vasculitis and other arterial changes, the existence of chronic interstitial nephritis and papillary necrosis and lesions associated with gold and penicillamine therapy.  相似文献   
27.
Recent results obtained using molecular biology techniques have suggested a possible role for insulin-like growth factor II (IGF-II) in the pathogenesis of hepatocellular carcinoma (HCC). To investigate this phenomenon, a monoclonal anti-body was used against IGF-II to study 54 patients with HCC. The presence of HBsAg was also tested both in serum and liver tissue. A positive immunoreaction was found in 9/15 (60%) of the HCC arising in cirrhotic livers of patients who had serum markers for HBV (HBV+ positive patients). These results provide further evidence that HBV might play a role in the expression of IGF-II. In HCC of patients without any markers of HBV infection (HBV- negative patients), IGF–II was detected in 10/39 (25.6%) of the tumors, and in some benign neoplastic lesions. It was found not only in neoplastic cells but also in some dysplastic nodules. The speculation arises that IGF–II expression may play a role in some steps of hepato-carcinogenesis.  相似文献   
28.
Lymphocyte subpopulations (B cells, CD4, CD8), interleukin-20 receptors (IL-2), monocytes/macrophages (Leu M5), and HLA-DR antigen expression were studied immunohistochemically on frozen sections from 38 bladder cancer specimens. T cells predominated over B cells in all tumours. CD4-positive lymphocytes predominated over CD8 in the stroma (CD4/CD8: 1·35/1), while in epithelial tumour cells CD8 was the prominent subpopulation (CD8/CD4: 1·75/1). Aberrant HLA-DR expression was found in 21·05 per cent of bladder tumours. A strong correlation between CD4 and CD8 population densities and macrophages with the other subpopulations was noticed. In HLA-DR-positive tumours, there was no correlation of the percentage of positive cells with CD4- and CD8-positive lymphocyte populations. Various parameters including IL-2 receptors, B cells, CD8- and CD4-positive cells, and macrophages did not differ significantly between the groups of tumours expressing and not expressing HLA-DR antigen. There were no statistically significant differences in the population densities of B cells, CD8- or CD4-positive cells, IL-2 receptor, monocytes/macrophages, and HLA-DR antigen expression among various clinicopathological parameters, including growth pattern, histological grade and clinical stage or patient's age and sex. These findings suggest that in transitional cell carcinoma of the urinary bladder, HLA-DR antigen expression is independent of lymphocyte subpopulations. It is therefore possible that HLA-DR expression by tumour cells reflect the existence of separate HLA-DR-positive or HLA-DR-negative tumour clones.  相似文献   
29.
30.
Helicobacter pylori (HP) infection is a common and persistent disorder acting as a major cofactor for the development of upper gastrointestinal diseases and several extraintestinal disorders including osteoporosis. However, no prospective study assessed the effects of HP on bone health and fracture risk. We performed a HP screening in a population-based cohort of 1149 adults followed prospectively for up to 11 years. The presence of HP infection was assessed by serologic testing for serum antibodies to HP and the cytotoxin associated gene-A (CagA). The prevalence of HP infection did not differ among individuals with normal bone mineral density (BMD), osteoporosis, and osteopenia. However, HP infection by CagA-positive strains was significantly increased in osteoporotic (30%) and osteopenic (26%) patients respect to subjects with normal BMD (21%). Moreover, anti-CagA antibody levels were significantly and negatively associated with lumbar and femoral BMD. Consistent with these associations, patients affected by CagA-positive strains had a more than fivefold increased risk to sustain a clinical vertebral fracture (HR 5.27; 95% CI, 2.23–12.63; p < .0001) and a double risk to sustain a nonvertebral incident fracture (HR 2.09; 95% CI, 1.27–2.46; p < .005). Reduced estrogen and ghrelin levels, together with an impaired bone turnover balance after the meal were also observed in carriers of CagA-positive HP infection. HP infection by strains expressing CagA may be considered a risk factor for osteoporosis and fractures. Further studies are required to clarify in more detail the underlying pathogenetic mechanisms of this association. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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