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91.
Patricia Rojas Pérez-Ezquerra Maria Vazquez Torre de la Gaspar Manuel Barrio de Fernández Vanesa Tovar Flores Ana Villanueva Alvarez-Santullano Maria Luisa Baeza Ochoa de Ocáriz 《Annals of allergy, asthma & immunology》2007,98(5):480-482
BACKGROUND: Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported. OBJECTIVES: To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens. METHODS: Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens. RESULTS: Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only. CONCLUSIONS: We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens. 相似文献
92.
Bone marrow-derived mesenchymal stem cells in repair of the injured lung 总被引:26,自引:0,他引:26
Rojas M Xu J Woods CR Mora AL Spears W Roman J Brigham KL 《American journal of respiratory cell and molecular biology》2005,33(2):145-152
We sought to determine whether an intact bone marrow is essential to lung repair following bleomycin-induced lung injury in mice, and the mechanisms of any protective effects conferred by bone marrow-derived mesenchymal stem cell (BMDMSC) transfer. We found that myelosupression increased susceptibility to bleomycin injury and that BMDMSC transfer was protective. Protection was associated with the differentiation of engrafted BMDMSC into specific and distinct lung cell phenotypes, with an increase in circulating levels of G-CSF and GM-CSF (known for their ability to promote the mobilization of endogenous stem cells) and with a decrease in inflammatory cytokines. In vitro, cells from injured, but not from normal, mouse lung produced soluble factors that caused BMDMSC to proliferate and migrate toward the injured lung. We conclude that bone marrow stem cells are important in the repair of bleomycin-injured lung and that transfer of mesenchymal stem cells protects against the injury. BMDMSC localize to the injured lung and assume lung cell phenotypes, but protection from injury and fibrosis also involves suppression of inflammation and triggering production of reparative growth factors. 相似文献
93.
Maria Suárez-Cervera Teresa Castells Ana Vega-Maray Esther Civantos Victoria del Pozo Delia Fernández-González Stella Moreno-Grau Angel Moral Carmen López-Iglesias Carlos Lahoz Juan A Seoane-Camba 《Annals of allergy, asthma & immunology》2008,101(1):57-66
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
94.
Interleukin-10 secreted by B-1 cells modulates the phagocytic activity of murine macrophages in vitro 总被引:3,自引:0,他引:3 下载免费PDF全文
As demonstrated previously in our laboratory, B-1 cells migrate from the peritoneal cavity of mice and home to a distant site of inflammation to become macrophage-like cells. However, the influence that these cells might have on the kinetics and fate of the inflammatory process is not known. Considering that macrophages are pivotal in the inflammatory reaction, we decided to investigate the possible influence B-1 cells could have on macrophage activities in vitro. Our results show that peritoneal macrophages from Xid mice, a mouse strain deprived of B-1 cells, have higher phagocytic indexes for zymozan particles when compared with macrophages from wild-type mice. Moreover, macrophages from wild-type mice have a lower ability to release nitric oxide and hydrogen peroxide when compared with macrophages from Xid mice. Experiments using cocultures of B-1 cells and macrophages from Xid mice in transwell plates demonstrated that B-1 cells down-regulate macrophage activities. These observations also indicate that this phenomenon is not due to a physical interaction between these two cell populations. As B-1 cells are one of the main sources of interleukin (IL)-10, we demonstrate in this study that adherent peritoneal cells from Xid mice produce significantly less amounts of this cytokine in culture when compared with IL-10 production by cells from wild-type mice. When B-1 cells from IL-10 knock-out mice and macrophages from wild-type mice were cocultured in transwell plates, the phagocytic index of macrophages was not altered demonstrating that B-1 cells can influence the effector functions of macrophages in vitro via IL-10 secretion. 相似文献
95.
Zamora-Perez A Zúñiga-González GM Gómez-Meda BC Ramos-Ibarra ML Batista-González CM Torres-Bugarín O 《Environmental and molecular mutagenesis》2004,44(5):436-440
The micronucleus (MN) assay can be used to detect the genotoxic effects of chemical agents in virtually any cell that divides frequently. Salamanders (Ambystoma sp.) are amphibians that can be easily maintained and bred in the laboratory and spontaneously shed their skin every 2.5-4 days. In this present study, we have evaluated the usefulness of this shed skin for the MN assay. We exposed salamanders to different concentrations of both the aneugen colchicine (COL) and the clastogen cyclophosphamide (CP) and we determined the frequency of micronucleated cells (MNCs) in their sheds. Fragments of shed skin were placed on clean slides, fixed, stained, observed with a light microscope, and the number of MNCs was counted. The MNC frequency was increased significantly by all doses of COL and CP tested, administered either as single or repeated exposures. The presence of MNCs in the shed skin and the speed of sloughing lead us to propose that the sheds of Ambystoma sp., or other amphibians that slough their skin, are suitable alternative models for detecting genotoxic exposures relevant to aquatic environments. 相似文献
96.
Gonzalo Herradon Laura Ezquerra Trang Nguyen Chi Wang Ana Siso Barbara Franklin Laura Dilorenzo Julie Rossenfeld Inmaculada Silos-Santiago Luis F. Alguacil 《Neuroscience letters》2008
The Fischer 344 (F344) rat strain differs from the Lewis strain in the response to neuropathic pain. Recently, we found that F344 rats totally recover from mechanical allodynia induced by chronic constriction injury (CCI) of the sciatic nerve 28 days after surgery whereas Lewis rats are initiating their recovery at this time point. Thus, the use of this neuropathic pain model in these different rat strains constitutes a good strategy to identify possible target genes involved in the development of neuropathic pain. Since differences between Lewis and F344 rats in their response to pain stimuli in acute pain models have been related to differences in the endogenous opioid and noradrenergic systems, we aimed to determine the levels of expression of key genes of both systems in the spinal cord and dorsal root ganglia (DRG) of both strains 28 days after CCI surgery. Real time RT-PCR revealed minimal changes in gene expression in the spinal cord after CCI despite the strain considered, but marked changes in DRG were observed. A significant upregulation of prodynorphin gene expression occurred only in injured DRG of F344 rats, the most resistant strain to neuropathic pain. In addition, we found a significant downregulation of tyrosine hydroxylase and proenkephalin gene expression levels in both strains whereas δ-opioid receptor was found to be significantly downregulated only in injured DRG of Lewis rats although the same trend was observed in F344 rats. The data strongly suggest that dynorphins could be involved in strain differences concerning CCI resistance. 相似文献
97.
The sequence is presented of RNA-5 of Echinochloa hoja blanca tenuivirus, a second tenuivirus associated with rice cultivation in Latin America (after rice hoja blanca virus). The RNA is 1334 nucleotides long and contains in the complementary sense RNA a single long open reading frame. The deduced amino acid sequence of this open reading frame shows that it encodes a highly basic and hydrophilic 44 kD protein (pc5) with about 50% similarity to the pc5 protein of maize stripe virus (MStV). This and other features of the RNA are discussed.The GenBank accession number of the sequence reported in this paper is L47430. 相似文献
98.
Susana Camacho Maria Del Valle Ostos José Ignacio Llorente Ana Sanz Manuel García Alberto Domezain Ramón Carmona 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(9):1178-1189
Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
99.
Presence of the cfxA gene in Bacteroides distasonis 总被引:1,自引:0,他引:1
Avelar KE Otsuki K Vicente AC Vieira JM de Paula GR Domingues RM Ferreira MC 《Research in microbiology》2003,154(5):369-374
In this study we investigated the presence of the cfxA gene (encoding a class A beta-lactamase) in 73 strains of the Bacteroides fragilis group belonging to the species B. distasonis (34), B. vulgatus (14), B. thetaiotaomicron (8), B. merdae (6), B. caccae (9) and B. ovatus (2) isolated from human intestinal microflora of healthy children and adults. Employing specific primers to the cfxA gene, a 312-bp amplified fragment was obtained in 2 strains of B. vulgatus and 9 strains, the majority from children, of B. distasonis. The expression of this enzyme was analysed by determining the MICs to cefoxitin and cefotaxime and values varied from 2 to >256 microg/ml of both cefoxitin and cefotaxime. Sequence analysis of the amplicons corresponding to the cfxA gene from B. distasonis and B. vulgatus revealed identical sequences between these isolates and high similarity with other beta-lactamase genes of anaerobes such as cfxA of B. vulgatus (99%) and cfxA2 of Prevotella intermedia (99%), both sequences of which deposited in Genbank under accession numbers U38243 and AF118110, respectively. However, a fragment obtained from a B. distasonis strain (EC17-4) showed a unique RFLP profile and 87% nucleotide similarity with cfxA and cfxA2 genes. These results seem to suggest a dissemination of these resistance determinants among Bacteroides species. 相似文献
100.
Arancha C Ruíz-Llorente S Cascón A Osorio A Martínez-Delgado B Benítez J Robledo M 《Journal of human genetics》2002,47(4):190-195
Until now, the study of the multiple endocrine neoplasia type 1 (MEN1) gene in patients suspected of having the disease was expensive and laborious due to the large size of the gene. We have
optimized the conformation-sensitive gel electrophoresis (CSGE) technique to analyze by four rather simple multiplex PCR reactions,
and a single electrophoresis run, the entire coding region of the MEN1 gene, plus the exon–intron boundaries. This improvement of the CSGE technique was confirmed as an effective procedure for
screening for the MEN1 gene by detecting ten previously known MEN1 gene mutations and four polymorphisms. The MEN1 gene of 12 patients with unknown mutations was then screened, and an abnormal CSGE profile was identified in 10/12 cases.
Subsequent DNA sequencing demonstrated 3 of them to be novel mutations (E45K, 4479delACAG, 6073insC) and 7 to have been previously
reported; in the remaining 2 patients, we confirmed the absence of any alteration of the coding sequence of MEN1. Mutation screening of the MEN1 gene using CSGE was demonstrated to be a fast, simple, and inexpensive method to study patients suspected of having MEN1
disease.
Received: November 29, 2001 / Accepted: January 28, 2002 相似文献