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Common Process (common + process)
Selected AbstractsComparative mechanisms of zearalenone and ochratoxin A toxicities on cultured HepG2 cells: Is oxidative stress a common process?ENVIRONMENTAL TOXICOLOGY, Issue 6 2009Emna El Golli Bennour Abstract Zearalenone (ZEN) and Ochratoxin A (OTA) are structurally diverse fungal metabolites that can contaminate feed and foodstuff and can cause serious health problems for animals as well as for humans. In this study, we get further insight of the molecular aspects of ZEN and OTA toxicities in cultured human HepG2 hepatocytes. In this context, we have monitored the effects of ZEN and OTA on (i) cell viability, (ii) heat shock protein (Hsp) 70 and Hsp 27 gene expressions as a parameter of protective and adaptive response, (iii) oxidative damage, and (iv) cell death pathways. Our results clearly showed that both ZEN and OTA inhibit cell proliferation. For ZEN, a significant induction of Hsp 70 and Hsp 27 was observed. In the same conditions, ZEN generated an important amount of reactive oxygen species (ROS). Antioxidant supplements restored the major part of cell mortality induced by ZEN. However, OTA treatment downregulated Hsp 70 and Hsp 27 protein and mRNA levels and did not induce ROS generation. Antioxidant supplements did not have a significant effect on OTA-induced cell mortality. Using another cell system (Vero monkey kidney cells), we demonstrated that OTA downregulates three members of HSP 70 family: Hsp 70, Hsp 75, and Hsp 78. Our findings showed that oxidative damage seemed to be the predominant toxic effect for ZEN, while OTA toxicity seemed to be rather because of the absence of Hsps protective response. Furthermore, the two mycotoxins induced an apoptotic cell death. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009. [source] In-group reassurance in a pain setting produces lower levels of physiological arousal: direct support for a self-categorization analysis of social influence,EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2007Michael J. Platow A large body of research demonstrates a strong social component to people's pain experiences and pain-related behaviours. We investigate this by examining the impact of social-influence processes on laboratory-induced pain responses by manipulating the social-categorical relationship between the person experiencing pain and another who offers reassurance. We show that physiological arousal associated with laboratory-induced pain is significantly lower in normal, healthy participants following reassurance about the pain-inducing activity when that reassurance comes from an in-group member in contrast to reassurance from an out-group member and a no reassurance control. These data are consistent with predictions derived from self-categorization theory, providing convincing empirical support of its analysis of social influence using a non-reactive measure. These data also represent a clear advance within the pain literature by identifying a possible common process to the social-psychological component of pain responses. Copyright © 2006 John Wiley & Sons, Ltd. [source] Immunohistochemical analysis of thyroid-specific transcription factors in thyroid tumorsPATHOLOGY INTERNATIONAL, Issue 5 2006Ping Zhang Thyroid transcription factor 1 (TTF1), thyroid transcription factor 2 (TTF2) and paired box gene 8 (Pax8) are demonstrated to play a crucial role for the differentiation and organogenesis of thyroid follicular cells. Their roles in thyroid carcinogenesis are not very clear. Because dedifferentiation is a common process in thyroid carcinogenesis, thyroid-specific transcription factors seem also to be involving in thyroid carcinogenesis. The purpose of the present paper was to investigate their expression in a broad spectrum of follicular cell tumors in different degrees of differentiation, from well-differentiated benign follicular adenoma to anaplastic carcinoma. Medullary (C cell) carcinoma was also included in the investigation. Results of immunohistochemical staining showed that nuclear localization of these transcription factors was gradually decreased corresponding to the progressive dedifferentiation of thyroid tumors. Also, abnormal cytoplasmic accumulation of TTF2 and Pax8 was detected in many tumors samples, which may indicate a subtle regulation mechanism on the function of these transcription factors. In conclusion, abnormal expression of TTF1, TTF2 and Pax8 was closely related to thyroid tumorigenesis. [source] Arabidopsis Bax inhibitor-1 functions as an attenuator of biotic and abiotic types of cell deathTHE PLANT JOURNAL, Issue 6 2006Naohide Watanabe Summary Programmed cell death (PCD) is a common process in eukaryotes during development and in response to pathogens and stress signals. Bax inihibitor-1 (BI-1) is proposed to be a cell death suppressor that is conserved in both animals and plants, but the physiological importance of BI-1 and the impact of its loss of function in plants are still unclear. In this study, we identified and characterized two independent Arabidopsis mutants with a T-DNA insertion in the AtBI1 gene. The phenotype of atbi1-1 and atbi1-2, with a C-terminal missense mutation and a gene knockout, respectively, was indistinguishable from wild-type plants under normal growth conditions. However, these two mutants exhibit accelerated progression of cell death upon infiltration of leaf tissues with a PCD-inducing fungal toxin fumonisin B1 (FB1) and increased sensitivity to heat shock-induced cell death. Under these conditions, expression of AtBI1 mRNA was up-regulated in wild-type leaves prior to the activation of cell death, suggesting that increase of AtBI1 expression is important for basal suppression of cell death progression. Over-expression of AtBI1 transgene in the two homozygous mutant backgrounds rescued the accelerated cell death phenotypes. Together, our results provide direct genetic evidence for a role of BI-1 as an attenuator for cell death progression triggered by both biotic and abiotic types of cell death signals in Arabidopsis. [source] Anion exchange chromatography provides a robust, predictable process to ensure viral safety of biotechnology productsBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Daniel M. Strauss Abstract The mammalian cell-lines used to produce biopharmaceutical products are known to produce endogenous retrovirus-like particles and have the potential to foster adventitious viruses as well. To ensure product safety and regulatory compliance, recovery processes must be capable of removing or inactivating any viral impurities or contaminants which may be present. Anion exchange chromatography (AEX) is a common process in the recovery of monoclonal antibody products and has been shown to be effective for viral removal. To further characterize the robustness of viral clearance by AEX with respect to process variations, we have investigated the ability of an AEX process to remove three model viruses using various combinations of mAb products, feedstock conductivities and compositions, equilibration buffers, and pooling criteria. Our data indicate that AEX provides complete or near-complete removal of all three model viruses over a wide range of process conditions, including those typically used in manufacturing processes. Furthermore, this process provides effective viral clearance for different mAb products, using a variety of feedstocks, equilibration buffers, and different pooling criteria. Viral clearance is observed to decrease when feedstocks with sufficiently high conductivities are used, and the limit at which the decrease occurs is dependent on the salt composition of the feedstock. These data illustrate the robust nature of the AEX recovery process for removal of viruses, and they indicate that proper design of AEX processes can ensure viral safety of mAb products. Biotechnol. Bioeng. 2009;102: 168,175. © 2008 Wiley Periodicals, Inc. [source] Is AZOOR an autoimmune disease?ACTA OPHTHALMOLOGICA, Issue 2007SF SEIDOVA Purpose: Acute zonal occult outer retinopathy (AZOOR) is one of the "white dot syndromes" a clinically heterogeneous group of inflammatory chorioretinopathies. The etiology is not yet clear. Methods: We present a 50 years female patient with a prior history of migraine. She experienced progressive visual loss and visual field defects in the last 3 years. Preceding each episode she experienced blue flickering photopsias. Results: Visual acuity was 0,3 in the right eye and 0,6 in the left eye. Biomicroscopy showed a normal anterior segment, fundus exam revealed pigment epithelial atrophy more pronounced in the worse eye. Electrophysiology showed a marked reduction in the photopic ERG in the more affected eye. MRI demonstrated multiple white matter lesions including a corpus callosum location. Lumbar puncture showed oligoclonal bands. Further tests demonstrated hearing impairment. Therapy was instituted during the three years course of the disease with steroids, immune suppressants and plasmapheresis with visual loss being progressive. New photopsia is currently present. Conclusions: The etiology of AZOOR remains unclear. With our patient being one of the few described in the literature with concomitant multiple sclerosis, the question remains on whether there is an underlying common process of inflammatory autoimmune reactions. Whether treatment is possible, remains to be evaluated. [source] Phylogenetic analysis of bovine pestiviruses: testing the evolution of clinical symptomsCLADISTICS, Issue 5 2004L. R. Jones This study presents a phylogenetic analysis of 115 bovine pestiviruses. A sequence data set from the 5, untranslated genomic region was analyzed with maximum parsimony, bootstrapping and parsimony jackknifing. We tested for the proposed classifications of the group and analyzed the evolution of the symptoms associated with Pestivirus infections in bovines. Based on the historical framework provided by our phylogenetic trees, we also characterized the extent and importance of contamination caused in biologicals by the virus. Our phylogenetic analyses showed that the previously defined genotypes are monophyletic, except for genotype 1a. Based on our cladograms, we propose the existence of more than 12 monophyletic groups within the species BVDV 1. The mapping of clinical symptoms suggests that the emergence of some genotypes could have been driven by a change in the pathogenic process. Enteric Problems appear to be ancestral, while Reproductive and Respiratory Problems arise with the emergence of genotypes 1b, 1d and the herein-proposed genotype Arg 1. The distribution of contaminant strains on the cladograms shows that pestiviral contamination is a common process, and also suggests that a contaminated product might be a vehicle for virus dispersion. Implications for virus evolution, virus taxonomy, veterinary medicine and biotechnology are discussed. [source] Sequential radiation of unrelated organisms: the gall fly Eurosta solidaginis and the tumbling flower beetle Mordellistena convictaJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2003W. G. Abrahamson Abstract Host shifts and the formation of insect-host races are likely common processes in the speciation of herbivorous insects. The interactions of goldenrods Solidago (Compositae), the gall fly Eurosta solidaginis (Diptera: Tephritidae) and the beetle Mordellistena convicta (Coleoptera: Mordellidae) provide behavioural, ecological and genetic evidence of host races that may represent incipient species forming via sympatric speciation. We summarize evidence for Eurosta host races and show that M. convicta has radiated from goldenrod stems to Eurosta galls to form host-part races and, having exploited the galler's host shift, has begun to differentiate into host races within galls. Thus, host-race formation has occurred in two interacting, but unrelated organisms representing two trophic levels, resulting in ,sequential radiation' (escalation of biodiversity up the trophic system). Distributions of host races and their behavioural isolating mechanisms suggest sympatric differentiation. Such differentiation suggests host-race formation and subsequent speciation may be an important source of biodiversity. [source] | |||||||||||||