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71.
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
72.
Molecular detection of Histoplasma capsulatum var. capsulatum in human clinical samples 总被引:2,自引:0,他引:2
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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
73.
Prabhakar V Grinstaff MW Alarcon J Knors C Solan AK Niklason LE 《Journal of biomedical materials research. Part A》2003,67(1):303-311
Techniques have been developed to culture bovine or porcine vascular cells on polyglycolic acid (PGA) scaffolds to form engineered vessels. Previously, it was shown that smooth muscle cells (SMCs) that were in close proximity to PGA remnants after 8 weeks of culture had lower expression of SMC markers of differentiation and were more mitotic compared with SMCs that were distant from polymer residuals. Modifications of PGA were explored as a means to minimize residual polymer fragments after culture. To hasten degradation, polymer was treated with heat, NaOH, or gamma-irradiation. Differential scanning calorimetry, mass and tensile strength degradation, and inherent viscosity were used to assess polymer characteristics. When polymer was maintained in aqueous conditions, tensile strength of treated PGA degraded to zero within 3 weeks for each treatment. Engineered vessel constructs cultured on NaOH and gamma-treated polymer displayed smooth muscle alpha-actin throughout the vessel wall. Scaffold treatment impacted graft morphology, cellular differentiation, and mechanical integrity. 相似文献
74.
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
75.
García-Sellés FJ Díaz-Perales A Sánchez-Monge R Alcántara M Lombardero M Barber D Salcedo G Fernández-Rivas M 《International archives of allergy and immunology》2002,128(2):115-122
BACKGROUND: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). METHODS: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. RESULTS: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. CONCLUSIONS: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy. 相似文献
76.
Andersson J Sanchez J Ekdahl KN Elgue G Nilsson B Larsson R 《Journal of biomedical materials research. Part A》2003,67(2):458-466
Contact between blood and a biomaterial surface takes place in many applications and is known to activate the coagulation and complement systems. Heparin surface coatings have been shown to reduce blood activation upon contact with artificial surfaces. To establish the optimal heparin surface concentration, blood was incubated in a tubing loop model at 37 degrees C. The tubing was coated with different surface concentrations of heparin and rotated at three different velocities. We demonstrate that the blood compatibility of a surface with regard to coagulation, complement, and platelet activation can be improved by increasing the heparin surface concentration in the 6-12 pmol antithrombin/cm2 concentration interval. The binding of factor H is not influenced by the increased heparin surface concentration, suggesting that this factor is not the primary regulator of complement on heparin surfaces. In addition, the heparin coating has no effect on the complement activation that occurs on gas surfaces in extracorporeal circuits. 相似文献
77.
Effects of dexamethasone and transient malnutrition on rabbits infected with aerosolized Mycobacterium tuberculosis CDC1551
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Kesavan AK Mendez SE Hatem CL Lopez-Molina J Aird K Pitt ML Dannenberg AM Manabe YC 《Infection and immunity》2005,73(10):7056-7060
Malnutrition is common in the developing world, where tuberculosis is often endemic. Rabbits infected with aerosolized Mycobacterium tuberculosis that subsequently became inadvertently and transiently malnourished had compromised cell-mediated immunity comparable to that of the rabbits immunosuppressed with dexamethasone. They had significant leukopenia and reduced delayed-type hypersensitivity responses. Malnutrition dampened cell-mediated immunity and would interfere with diagnostic tests that rely on intact CD4 T-cell responses. 相似文献
78.
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
79.
Blümel JE Castelo-Branco C Kerrigan N Cancelo MJ Blümel B Haya J Flores M Carvajal MC Sarrá S 《Menopause (New York, N.Y.)》2003,10(3):235-240
OBJECTIVE: To assess the beliefs of climacteric women regarding their health, menopause, and hormone replacement therapy (HRT). DESIGN: Medical students asked to interview 526 healthy women, ranging from 40 to 64 years of age, between January and February of 2002. Of that number, 26 (4.9%) declined to participate in the interview. Thus, 500 women were interviewed about their beliefs and perceptions regarding their quality of life and health risks, as well as their opinions on menopause and HRT. RESULTS: The mean age of the sample was 53.3 +/- 6.2 years; 83.4% were postmenopausal, and 18.8% were HRT users. Of the women interviewed, 38.6% believed that their health was good. Although 78.8% thought that cancer is the main cause of death, 64% of them considered themselves to be at high risk for cardiovascular disease and osteoporosis. Most (64%) believed that menopause deteriorates the quality of life and that it increases cardiovascular risk (52.4%) and osteoporosis (72.0%). The HRT users perceived that they had better health status (48.9% v 36.2%, P < 0.02) and smaller cardiovascular risk (54.3% v 66.3%, P < 0.04) than did the nonusers; however, they ignored the preventive effect of estrogens in osteoporosis. CONCLUSIONS: Women believe that menopause deteriorates their health. The HRT users perceived themselves to be healthier and to have a smaller risk for cardiovascular disease. 相似文献
80.
Specific allergens enhance elastase release in stimulated neutrophils from asthmatic patients 总被引:12,自引:0,他引:12
Monteseirín J Bonilla I Camacho MJ Chacón P Vega A Chaparro A Conde J Sobrino F 《International archives of allergy and immunology》2003,131(3):174-181
BACKGROUND: The presence of the three forms of IgE receptor - the heterotrimeric high-affinity receptor for IgE (Fc(epsilon)RI), the low-affinity receptor for IgE (Fc(epsilon)RII/CD23) and the Mac-2/IgE-binding protein (epsilonBP) - has been demonstrated on human neutrophils. We have previously shown that specific allergens are able to activate functional responses by neutrophils from allergic patients sensitized to those allergens. Neutrophils are present at the sites of allergic inflammation. The primary (azurophilic) granules of neutrophils contain a variety of enzymes, such as elastase, that might potentiate inflammation. It is not known whether specific allergens are able to elicit elastase release by neutrophils from allergic patients. In addition, we attempted to evaluate the relationship between neutrophil degranulation and lung function of the patients, measured as FEV(1). METHODS: Neutrophils were challenged in vitro with the specific allergens that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Neutrophils from normal subjects were challenged with allergens as control. RESULTS: The in vitro challenge of neutrophils with allergens to which the patients were sensitive elicited a release of elastase by these cells. The in vitro activation of neutrophils was highly allergen specific; allergens other than those accounting for clinical symptoms did not evoke elastase release, and allergens were ineffective on neutrophils from healthy donors. A significant inverse correlation was observed between elastase release and patients' lung function, measured as FEV(1). CONCLUSION: An IgE-dependent mechanism might promote elastase release by neutrophils at allergic sites. There is a significant inverse relationship between levels of elastase released by neutrophils from allergic patients and lung function, as assessed by FEV(1). 相似文献