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71.
Lopata AL Jeebhay MF Reese G Fernandes J Swoboda I Robins TG Lehrer SB 《International archives of allergy and immunology》2005,138(1):21-28
BACKGROUND: Aerosolization of fish proteins during seafood processing has been identified as a potential route for allergic sensitization and occupational asthma among workers involved in high-risk activities. The aim of this study was to develop immunological assays for the quantification of aerosolized fish antigens in a fish-processing factory. METHODS: Polyclonal antibodies to the main fish species processed in the factory (anchovy and pilchard) were generated in rabbits and compared by ELISA inhibition assay and immunoblotting. These antisera were utilized to develop ELISA assays for the detection of fish antigens. The ELISA inhibition assays were evaluated by analyzing environmental air samples collected from three areas in a fish-processing factory: pilchard canning, fish meal production and lobster processing. RESULTS: By immunoblotting, the rabbit polyclonal antibodies demonstrated IgG antibody binding patterns comparable with IgE antibodies of fish-sensitized patients, particularly in regard to the major fish allergens parvalbumins. The sensitivity of the fish-specific ELISA assays developed was 0.5 microg/ml. The ELISA inhibition assays were able to differentiate between the two different fish species of interest but did not recognize a crustacean species. Notable differences in exposure levels to canned pilchard and anchovy antigens were demonstrated in the three different working areas of the factory, with assays having a detection limit as low as 105 ng/m(3). CONCLUSION: These ELISA-based assays are sensitive and specific to quantify differential exposure levels to fish antigens produced during fish processing, making it possible to investigate exposure-disease response relationships among workers in this industry. 相似文献
72.
Bernard Boutevin Yves Pitrasanta Mohamed Taha Tarek El Sarraf 《Macromolecular chemistry and physics.》1983,184(12):2401-2407
New macromers 4, 8, and 10, containing ester, alcohol, or acid functions, were prepared starting with vinyl chloride (CV) or vinylidene dichloride (CV2). The telomer 1, resulting from CV2 and CCI4 was telomerized with allyl acetate and the product was transformed into the acrylate 4 by hydrolysis of the reaction product and subsequent esterification. Macromers 8 and 10 were prepared from CV by radical telomerization with thioglycolic acid (7) and 2-mercaptoethanol (9), respectively. Reactive double bonds were introduced into these macromers by reaction with acrylic acid, Vinyl chloroformate, methacryloyl chloride, or 2,3 -epoxypropyle methacrylate, leading to new macromers 12, 13, 14, and 15, respectively. 相似文献
73.
Peres EM Savasan S Cushing B Abella S Mohamed AN 《Cancer Genetics and Cytogenetics》2004,148(1):66-70
Cytogenetic analyses of 16 cases of Wilms tumor with abnormal karyotypes were reviewed, 15 cases of unilateral tumor and 1 bilateral. Three tumors exhibited an unfavorable histology (i.e., anaplastic changes); the rest fell into the favorable histology group. Of the 17 tumors with abnormal clonal aberrations, 9 tumors were hyperdiploid (53%), 7 had pseudodiploid karyotypes (41%), and 1 was hypodiploid (6%). The most common numerical aberrations in descending order of frequency were gain of chromosomes 12, 8, and 6 and loss of chromosome 16. Structural rearrangements mostly involved chromosome 1, followed by chromosomes 7, 14, and 17. Clustering of breaks around 1p22 approximately p31-->pter resulting in partial loss of 1p was the most frequent structural aberration. Additionally, i(7q) was observed as a sole abnormality in two tumors and a 7p translocation in two other tumors. Two other recurrent abnormalities were a partial deletion of 14q, seen in three tumors, and complete loss of chromosome 14 in one tumor. All three Wilms tumors with unfavorable histology had abnormalities of 17p, resulting in TP53 gene deletion. These findings provide further support for the importance of gains of chromosomes 12, 8, and 6 and loss of 1p in the development of Wilms tumor. The results also support the association of unfavorable-histology Wilms tumors with TP53 deletion. The nonrandom losses of 16/16q, 7p, and 14q may point to the importance of genomic imbalance in the pathogenetic consequences and progression of Wilms tumor. 相似文献
74.
Hassan Izaabel Henri-Jean Garchon Geneviève Beaurain Mohamed Biga Omar Akhayat Jean-François Bach Sophie Caillat-Zucman 《Human immunology》1996,49(2):137-143
HLA class II polymorphism in Moroccan IDDM patients has not been investigated so far. In this study, HLA-DRB1, -DQA1, and -DQB1 allele and haplotype frequencies were analyzed in 125 unrelated Moroccan IDDM patients and 93 unrelated healthy controls, all originating from the Souss region and mostly of Berber origin. Some common features with other Caucasian groups were observed, in particular, a predisposing effect of the DRB1*03-DQA1*0501-DQB1*0201 and DRB1*04-DQA1*0301-DQB1*0302 alleles or allelic combinations. The Moroccan IDDM group also presented with more specific characteristics. Among DRB1*04 subtypes, DRB1*0405 was associated with susceptibility to and DRB1*0406 with protection from the disease. The haplotype and the relative predispositional effect (RPE) analyses indicated that the DRB1*08-DQA1*0401DQB1 *0402 haplotype was also associated with susceptibility to IDDM. Interestingly, the DRB1*09DQA1 *0301-DQB1*0201 haplotype, completely absent from the control group and very rare in North African populations, was observed in 7.2% of the Moroccan diabetics. Conversely, the DRB1*07-DQA1*0201DQB1 *0201 and DRB1*15-DQA1*0102-DQB1*0602 haplotypes were associated with protection from IDDM. Finally, we observed an age-dependent genetic heterogeneity of IDDM, the frequencies of predisposing alleles being higher and those of protective alleles lower in childhood- than in adult-onset diabetics. Our data on Moroccan diabetics, together with data on European and Northern Mediterranean patients, suggest a gradient of various HLA class II predisposing and protective markers that link these populations 相似文献
75.
76.
M A Micale A Mohamed W Sakr I J Powell S R Wolman 《Cancer Genetics and Cytogenetics》1992,61(2):165-173
We have examined 62 prostatic adenocarcinomas by conventional cytogenetic analysis. Most were primary cultures harvested in 14 days or less. The most consistent finding was a normal male diploid karyotype, found in 87% of all cells analyzed, and as the exclusive finding in 19 tumors. Nonrandom chromosomal changes included gain of chromosome 7 and loss of the Y chromosome. In addition, clonal gains of chromosomes 8, 12, and 18, and clonal losses of chromosomes 14 and 19 were noted in individual cases. Two structural clonal aberrations, a 9p+ in one case and a t(Y;22) (q11.2;p12) in another, were also seen. Ten of 62 cultures demonstrated chromosome instability, defined herein as nonclonal gain or loss of chromosomes in more than 10% of the metaphases examined from that culture. In those cases with nonclonal numerical aberrations, loss of chromosomes was more common than gain. The distribution of apparently random numeric abnormalities was similar to that of the clonal abnormalities in that the most frequent nonclonal gain was of chromosome 7 and the most frequent nonclonal loss was of the Y chromosome. Apparently random structural aberrations were observed in less than 1% of all analyzed cells. These included a 4p-,del(3)(q13), and t(1;11). The extent of apparently random aneuploidy suggests that chromosome instability characterizes cultured prostatic adenocarcinomas. An increase in the frequency of nonclonal aberrations may be an indicator of tumor origin in a predominantly diploid cell population. The coexistence of clonally aberrant, nonclonally aberrant, and normal diploid cells in culture may reflect heterogeneity of prostate tumors in vivo. 相似文献
77.
Photodynamic therapy (PDT) is a clinical approach that utilizes light-activated drugs for the treatment of a variety of pathologic conditions. Human poorly (CNE2) and moderately differentiated (TW0-1) human nasopharyngeal carcinoma (NPC) cells undergo rapid apoptosis when treated with PDT sensitized with Hypocrellin A (HA) and Hypocrellin B (HB). It has been shown that these compounds have a strong photodynamic effect on tumors and viruses. The initiating events of PDT sensitized HA and HB-induced apoptosis are poorly defined. In the current study, we sought to determine whether Fas/FasL upregulation and involvement of mitochondrial events are an early event in HA and HB-treated PDT induced apoptosis. Loss of mitochondrial transmembrane potential, release of cytochrome c, involvement of caspases-8 and -3 and the status caspase-3 specific substrate PARP, were evaluated in PDT treated tumor cells. Photoactivation of HA and HB enhanced both CD95/CD95L expression and induced CD95-signaling dependent cell death in all tumor cell lines studied. CD95/ CD95L expression appeared within 2 h following light activation and appeared to be a primary event in PDT induced apoptosis. Furthermore, these results indicate that release of mitochondrial cytochrome c into the cytoplasm is a secondary event following the activation of initiator caspase-8 preceding caspase-3 activation, cleavage of PARP and DNA fragmentation. Cytochrome c appeared in the cytosol within 2-3 h post PDT. Cleavage of PARP was observed at 3-4 h following PDT and caspase-3 specific inhibitor DEVD-CHO and broad-spectrum caspases inhibitor z-VAD-fmk blocked caspase-3 activation and PARP cleavage suggesting that caspase-3 plays an important role in HA and HB-induced apoptosis. 相似文献
78.
Stéphanie Caharel Nicole Fiori Christian Bernard Robert Lalonde Mohamed Reba? 《International journal of psychophysiology》2006,62(1):141-151
OBJECTIVES: The objective of this study is to examine whether configural alterations of faces affect early or late processing stages as a function of their familiarity and their level of representation in memory. We then sought to verify whether the structural encoding stage is susceptible to top-down influences. METHODS: Electrophysiologic and behavioral studies were undertaken, during which unknown and familiar faces were presented upright or upside-down with or without feature alterations. The subjects were asked to determine whether the faces were familiar or not. RESULTS: N170 and N360 amplitudes were larger for familiar faces as well as altered ones. A higher degree of familiarity decreased reaction times (RTs) and N360 latencies, but increased N170 latencies, whereas face alterations increased RTs and latencies of both components examined. However, familiarity interacted with altered face configurations only for RTs and the N170. SIGNIFICANCE: In the perceptual stage, familiar faces seem to develop a more elaborate type of processing because of top-down influences linked to the robust nature of their representations in memory. The more elaborate type of processing for familiar faces has advantageous consequences for the following steps of information processing, by facilitating access to structural representations in memory (N360) as well as the final step reflected by RTs. The fact that configural alterations cause different effects for familiar as opposed to unfamiliar faces indicate that these stimuli are processed in a qualitatively different manner and solicit different representations in memory. 相似文献
79.
Thierry Fargre Mohamed Abdennadher Michel Delmas Bernard Boutevin 《Macromolecular chemistry and physics.》1994,195(5):1673-1685
Polymers can be treated with an ozone/oxygen mixture to create peroxide and hydroperoxide groups on the polymer chain. These heat-sensitive functional groups can serve to initiate radical polymerization of vinyl monomers to form graft copolymers. The efficiency and the decomposition rate constant of an ozonized ethylene-vinyl acetate copolymer (EVA) are determined using the polymerization rate of styrene. The thermal polymerization of styrene is studied in the presence of non-ozonized EVA. The thermal polymerization has no effect on the polymerization of styrene at the beginning of the reaction. Transfer reactions between the growing polystyrene radical and the EVA chain are negligible. The activation energy of the decomposition rate of ozonized EVA is calculated and reaches 46 kJ/mol. The entropy variation of the decomposition reaction is also calculated. The result obtained shows an important decrease (?45 cal · mol?1 · K?1) of the entropy which is opposite to the common behaviour (?6 to +13 cal · mol?1 · K?1) expected. The efficiency observed for the ozonized polymers is low and reaches only 20% at 100°C, this can be explained by the lack of mobility of the created radicals. 相似文献
80.
Alhasani Rehab Auger Claudine Paiva Azevedo Matheus Ahmed Sara 《Quality of life research》2022,31(9):2567-2599
Quality of Life Research - While several mobility measures exist, there is large variability across measures in how mobility is conceptualized, the source of information and the measurement... 相似文献