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81.
C. Blanco T. Carrillo J. Quiralte C. Pascual M. Martin Esteban R. Castillo 《Allergy》1995,50(3):277-280
We report a case of occupational bronchial asthma and rhinoconjunctivitis caused by Phoenix canariensis (PC) pollen. The canary palm is a type of palm tree, belonging to the Arecaceae family, which is widely distributed in frost-free regions as an ornamental tree. Our patient was referred because he suffered symptoms of bronchial asthma, rhinoconjunctivitis, and contact urticaria when pruning dried leaves from PC during the pollination months. The skin prick test (SPT) with a PC pollen extract was positive, as was the specific IgE to PC pollen determined by Phadezym RAST, indicating an IgE-mediated sensitization. The nonspecific bronchial provocation test (BPT) performed with methacholine disclosed a mild bronchial hyperreactivity, and specific BPT with PC pollen elicited an immediate fall of 25% in FEV1 with respect to baseline. On RAST inhibition studies, a significant cross-reactivity was found between PC pollen and date palm ( P. dactylifera ) pollen. These results suggest that PC pollen could be a potential allergen in PC-growing areas. 相似文献
82.
Breakpoints for predicting Pseudomonas aeruginosa susceptibility to inhaled tobramycin in cystic fibrosis patients: use of high-range Etest strips 下载免费PDF全文
Morosini MI García-Castillo M Loza E Pérez-Vázquez M Baquero F Cantón R 《Journal of clinical microbiology》2005,43(9):4480-4485
Inhaled administration of tobramycin assures high concentrations in cystic fibrotic lungs, improving the therapeutic ratio over that of parenteral tobramycin levels, particularly against Pseudomonas aeruginosa. Conventional Clinical and Laboratory Standards Institute (CLSI; formerly National Committee for Clinical Laboratory Standards) breakpoints only consider parenteral levels and do not take into account these high antimicrobial concentrations. The Spanish Antibiogram Committee (The MENSURA Group) has tentatively defined specific breakpoint values for inhaled tobramycin when testing P. aeruginosa isolates from cystic fibrosis (CF) patients (susceptible, < or =64 microg/ml; resistant, > or =128 microg/ml). The antimicrobial susceptibilities of 206 prospectively collected CF P. aeruginosa isolates were determined by the reference agar dilution method. For tobramycin, the performance of high range tobramycin Etest strips (AB Biodisk, Solna, Sweden) and conventional tobramycin disks were assessed with the same collection. Applying MENSURA proposed breakpoints, 95.1% of the strains were categorized as susceptible to tobramycin, either using agar dilution or Etest high-range strips (99% categorical agreement between both methods). With CLSI breakpoints, susceptibility rates decreased to 79.1 and 81.1% for agar dilution and Etest strips, respectively (83.5% categorical agreement). Minor, major, and very major errors for Etest strips (CLSI criteria) were 13.6, 1.2, and 14.8%, respectively. Upon applying the new proposed criteria for inhaled tobramycin, only one major and one very major error were observed with Etest strips. Whenever inhaled tobramycin is considered for therapy, we suggest that P. aeruginosa strains from CF patients categorized as intermediate or resistant to tobramycin according to the CLSI criteria should be retested with high-range Etest strips and recategorized using MENSURA interpretive criteria. CLSI breakpoints should still be followed when intravenous tobramycin is used in CF patients, particularly during the course of exacerbations. 相似文献
83.
A STAT4-dependent Th1 response is required for resistance to the helminth parasite Taenia crassiceps 总被引:2,自引:0,他引:2 下载免费PDF全文
Rodríguez-Sosa M Saavedra R Tenorio EP Rosas LE Satoskar AR Terrazas LI 《Infection and immunity》2004,72(8):4552-4560
To determine the role of STAT4-dependent Th1 responses in the regulation of immunity to the helminth parasite Taenia crassiceps, we monitored infections with this parasite in resistant mice lacking the STAT4 gene. While T. crassiceps-infected STAT4(+/+) mice rapidly resolved the infection, STAT4(-/-) mice were highly susceptible to infection and displayed large parasite loads. Moreover, the inability of STAT4(-/-) mice to control the infection was associated with the induction of an antigen-specific Th2-type response characterized by significantly higher levels of Th2-associated immunoglobulin G1 (IgG1) and total IgE as well as interleukin-4 (IL-4), IL-10, and IL-13 than those in STAT4(+/+) mice, who produced significantly more gamma interferon. Furthermore, early after infection, macrophages from STAT4(-/-) mice produced lower levels of the pro-inflammatory cytokines IL-12, tumor necrosis factor alpha, IL-1 beta, and nitric oxide (NO) than those from STAT4(+/+) mice, suggesting a pivotal role for macrophages in mediating protection against cysticercosis. These findings demonstrate a critical role for the STAT4 signaling pathway in the development of a Th1-type immune response that is essential for mediating protection against the larval stage of T. crassiceps infection. 相似文献
84.
Javier Domínguez María del Mar Lorenzo Rafael Blasco 《Journal of immunological methods》1998,220(1-2):115-121
We have tested Green Fluorescent Protein (GFP) expressed by a vaccinia virus recombinant as a marker for viral infection. Virus recombinants expressing either wild-type GFP, or a Ser65 to Thr mutated version (GFP-S65T) were used to infect cultured cells, and the appearance of fluorescence was followed during infection by flow cytometry. Although both versions were detectable in infected cells, GFP-S65T gave up to 26-fold brighter fluorescence than wild-type GFP when excited by an argon laser beam (488 nm). In addition, GFP-S65T fluorescence appeared earlier, and infected cells could be detected above background as soon as 1 h after infection. We have used this construct to infect porcine peripheral blood lymphocytes, and show its usefulness to study virus tropism when used in combination with cell-type specific markers. Thus, GFP provides a direct, fast and convenient way to monitor infection by flow cytometry. 相似文献
85.
86.
Molecular detection of Histoplasma capsulatum var. capsulatum in human clinical samples 总被引:2,自引:0,他引:2 下载免费PDF全文
Bracca A Tosello ME Girardini JE Amigot SL Gomez C Serra E 《Journal of clinical microbiology》2003,41(4):1753-1755
We developed a seminested PCR for the diagnosis of histoplasmosis that amplifies a portion of the Histoplasma capsulatum H antigen gene. This assay is highly sensitive and specific, being able to detect genomic material corresponding to less than 10 yeast cells without cross-reaction against other bacterial or fungal pathogens. 相似文献
87.
García-Samaniego J Soriano V Miró JM Romero JD Bruguera M Castilla J Esteban JI Gonźlez J Lissen E Moreno A Moreno S Moreno-Otero R Ortega E Quereda C Rodríguez M Sánchez-Tapias JM;Spanish Hepatitis-HIV Consensus Panel 《HIV clinical trials》2002,3(2):99-114
Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed. 相似文献
88.
Pardo J Peled Y Bar J Hod M Sela BA Rafael ZB Orvieto R 《Human reproduction (Oxford, England)》2000,15(1):224-226
Low serum vitamin B(12) concentrations in pregnancy may not indicate true megaloblastic anaemia. In the present study we compared biochemical indices of vitamin B(12) deficiency (serum homocysteine and urine methylmalonic acid) in non-anaemic pregnant women with and without low serum vitamin B(12) concentrations. The groups were matched for age, parity and gestational age. No differences were found, and all values were within normal range. These results suggest that the measurement of low serum B(12) concentrations in pregnant women should be followed by analysis at the biochemical level before vitamin B(12) injections are started. 相似文献
89.
Özcan Özdamar Rafael E. Delgado Syed Rahman Carlos Lopez 《Annals of biomedical engineering》1998,26(5):883-891
An innovative acoustic noise canceling method using adaptive Wiener filtering (AWF) was developed for improved acquisition of distortion product otoacoustic emissions (DPOAEs). The system used one microphone placed in the test ear for the primary signal. Noise reference signals were obtained from three different sources: (a) pre-stimulus response from the test ear microphone, (b) post-stimulus response from a microphone placed near the head of the subject and (c) post-stimulus response obtained from a microphone placed in the subjects nontest ear. In order to improve spectral estimation, block averaging of a different number of single sweep responses was used. DPOAE data were obtained from 11 ears of healthy newborns in a well-baby nursery of a hospital under typical noise conditions. Simultaneously obtained recordings from all three microphones were digitized, stored and processed off-line to evaluate the effects of AWF with respect to DPOAE detection and signal-to-noise ratio (SNR) improvement. Results show that compared to standard DPOAE processing, AWF improved signal detection and improved SNR. © 1998 Biomedical Engineering Society.
PAC98: 4364Jb, 4360-c, 8790+y 相似文献
90.
Montero R Serrano L Dávila V Segura Y Arrieta A Fuentes R Abad I Valencia L Sierra P Camacho R 《Environmental and molecular mutagenesis》2003,42(3):216-222
Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed. 相似文献