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Several Similarities (several + similarity)
Selected AbstractsFrom protozoa to mammalian cells: a new paradigm in the life cycle of intracellular bacterial pathogensENVIRONMENTAL MICROBIOLOGY, Issue 3 2000Minireview It is becoming apparent that several intracellular bacterial pathogens of humans can also survive within protozoa. This interaction with protozoa may protect these pathogens from harsh conditions in the extracellular environment and enhance their infectivity in mammals. This relationship has been clearly established in the case of the interaction between Legionella pneumophila and its protozoan hosts. In addition, the adaptation of bacterial pathogens to the intracellular life within the primitive eukaryotic protozoa may have provided them with the means to infect the more evolved mammalian cells. This is evident from the existence of several similarities, at both the phenotypic and the molecular levels, between the infection of mammalian and protozoan cells by L. pneumophila. Thus, protozoa appear to play a central role in the transition of bacteria from the environment to mammals. In essence, protozoa may be viewed as a ,biological gym', within which intracellular bacterial pathogens train for their encounters with the more evolved mammalian cells. Thus, intracellular bacterial pathogens have benefited from the structural and biochemical conservation of cellular processes in eukaryotes. The interaction of intracellular bacterial pathogens and protozoa highlights this conservation and may constitute a simplified model for the study of these pathogens and the evolution of cellular processes in eukaryotes. Furthermore, in addition to being environmental reservoirs for known intracellular pathogens of humans and animals, protozoa may be sources of emerging pathogenic bacteria. It is thus critical to re-examine the relationship between bacteria and protozoa to further our understanding of current human bacterial pathogenesis and, possibly, to predict the appearance of emerging pathogens. [source] Analysis of the CD2 and spliceosomal Sm B/B, polyproline-arginine motifs defined by a monoclonal antibody using a phage-displayed random peptide libraryJOURNAL OF MOLECULAR RECOGNITION, Issue 6 2006Dimitri Monos Abstract The cytoplasmic region of the CD2 receptor of lymphocytes contains proline-rich motifs, which are involved in T cell activation and interleukin-2 production. An intracellular CD2 binding protein, CD2BP2, interacts with two tandem PPPPGHR segments of the CD2 tail. CD2BP2 contains a GYF (glycine-tyrosine-phenylalanine) domain that confers binding to these proline-rich sequences. Monoclonal antibody 3E10 that was previously raised against a peptide containing the CD2 PPPPGHR segment reacts with the native CD2 molecule and spliceosomal Sm B/B, proteins. To identify the exact epitope on the CD2 peptide recognized by 3E10, a phage-displayed combinatorial peptide library was used. Analysis of the selected clones revealed that the mAb 3E10 binds preferentially to the motif PxxPPGxR. Experiments using amino acid substitutions with synthetic peptides confirmed the reactivity of mAb 3E10 with this motif. In addition, we show that several similarities exist between this motif and the CD2BP2-GFY recognition motif PPGxR/K. Binding of antibody 3E10 indicates some degree of degeneracy, which is consistent with its ability to recognize structurally related polyproline,arginine motifs found in intracellular proteins including Sm B/B, proteins and other RNA binding proteins. Thus, mAb 3E10 can be used to specifically identify a sub-class of proline-rich motifs, and as such can be used to study the potential role of these proline-rich sequences in mediating protein-protein interactions. Copyright © 2006 John Wiley & Sons, Ltd. [source] Cystatin C colocalizes with amyloid-, and coimmunoprecipitates with amyloid-, precursor protein in sporadic inclusion-body myositis musclesJOURNAL OF NEUROCHEMISTRY, Issue 6 2003Gaetano Vattemi Abstract Cystatin C (CC), an endogenous cysteine protease inhibitor, is accumulated within amyloid-, (A,) amyloid deposits in Alzheimer's disease (AD) brain and was proposed to play a role in the AD pathogenesis. Because the chemo-morphologic muscle phenotype of sporadic inclusion-body myositis (s-IBM) has several similarities with the phenotype of AD brain, including abnormal accumulation of A, deposits, we studied expression and localization of CC in muscle biopsies of 10 s-IBM, and 16 disease- and five normal-control muscle biopsies. Physical interaction of CC with amyloid-, precursor protein (A,PP) was studied by a combined immunoprecipitation/immunoblotting technique in the s-IBM muscle biopsies and in A,PP-overexpressing cultured human muscle fibers. In all s-IBM muscle biopsies, CC-immunoreactivity either colocalized with, or was adjacent to, the A,-immunoreactive inclusions in 80,90% of the vacuolated muscle fibers, mostly in non-vacuolated regions of their cytoplasm. Ultrastructurally, CC immunoreactivity-colocalized with A, on 6,10 nm amyloid-like fibrils and floccular material. By immunoblotting, CC expression was strongly increased in IBM muscle as compared to the controls. By immunoprecipitation/immunoblotting experiments, CC coimmunoprecipitated with A,PP, both in s-IBM muscle and in A,PP-overexpressing cultured normal human muscle fibers. Our studies (i) demonstrate for the first time that CC physically associates with A,PP, and (ii) suggest that CC may play a novel role in the s-IBM pathogenesis, possibly by influencing A,PP processing and A, deposition. [source] The distribution and expression of a biotrophy-related gene, CIH1, within the genus ColletotrichumMOLECULAR PLANT PATHOLOGY, Issue 4 2000Sarah E. Perfect During the biotrophic phase of the infection process of the hemibiotrophic anthracnose fungus Colletotrichum lindemuthianum, an intracellular hypha develops within epidermal cells of its host, Phaseolus vulgaris. This is followed by the formation of secondary hyphae during the necrotrophic phase. Previous work using a monoclonal antibody, UB25, has identified a glycoprotein that is specific to the interfacial matrix that forms between the wall of the intracellular hypha and the invaginated host plasma membrane. The gene encoding the protein identified by UB25 was cloned by immunoscreening and designated CIH1. The predicted amino acid sequence revealed a proline-rich glycoprotein, and biochemical evidence suggested that it formed a cross-linked structure at the biotrophic interface. Although CIH1 is a fungal gene, its product has several similarities to plant cell wall proteins. In this paper, we have surveyed the distribution and expression of CIH1 within the genus Colletotrichum, encompassing both necrotrophic and hemibiotrophic species. The results show that homologues of the CIH1 gene are present in all the Colletotrichum species tested. Northern blot studies of the time course of the infection process in planta have shown that CIH1 is expressed by both C. lindemuthianum in bean and C. trifolii in alfalfa during the biotrophic phase of fungal development. Immunofluorescence labelling of infected epidermal strips with UB25 revealed that the intracellular hyphae formed by C. destructivum as it infects alfalfa were specifically labelled in a similar way to those formed by C. lindemuthianum in bean. Northern and Western analysis showed that CIH1 was also expressed by C. lindemuthianum in vitro, though not constitutively. Overall, the evidence supports a role for CIH1 in biotrophy within the genus Colletotrichum. [source] Cognitive insights into the highly skilled or expert salespersonPSYCHOLOGY & MARKETING, Issue 2 2006C. David Shepherd A cognitive psychology based approach is used to investigate the highly skilled or expert salesperson. The study utilized verbal protocol analysis to identify differences in the decision processes of expert and less-skilled salespeople as they progressed through a difficult selling situation. The results of this study indicate that experts in sales share several similarities with experts in such diverse fields as chess, medicine, physics, and teaching. For example, expert salespeople were shown to reach better decisions in a faster and more confident manner than their less-skilled contemporaries. Further, in resolving current problems, experts were shown to be more likely to utilize their memory of previous selling situations, as well as to employ different strategies for customer interactions than less-skilled salespeople. © 2006 Wiley Periodicals, Inc. [source] Annotation: Childhood-onset schizophrenia: clinical and treatment issuesTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2004Joan Rosenbaum Asarnow Background:, In the past 10 years, there has been increased research on childhood-onset schizophrenia and clear advances have been achieved. Method:, This annotation reviews the recent clinical and treatment literature on childhood-onset schizophrenia. Results:, There is now strong evidence that the syndrome of childhood-onset schizophrenia exists and there are several similarities between childhood- and later-onset schizophrenia. Schizophrenia in youth can be reliably diagnosed using the same criteria employed with adults, and childhood-onset schizophrenia is predictive of schizophrenia or schizophrenia spectrum disorders in adulthood. Data is accumulating to guide pharmacological treatment strategies, and practice parameters have been developed to guide clinical care. Conclusions:, Despite significant advances, there remains an urgent need for additional research on treatment and service delivery strategies. Promising work with adults highlights the importance of attending to psychosocial as well as pharmacologic treatment strategies, and the potential value of preventive interventions. [source] Screening of Volatile Composition of Lavandula hybridaReverchon II Honey Using Headspace Solid-Phase Microextraction and Ultrasonic Solvent ExtractionCHEMISTRY & BIODIVERSITY, Issue 3 2009Igor Jerkovi Abstract The volatiles of unifloral Lavandula hybridaReverchon II honey were isolated by means of headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) and analyzed by gas chromatography and mass spectrometry (GC, GC/MS). A total of 23 compounds were identified in the headspace with hexan-1-ol, hexanal, acetic acid, hotrienol, and 2-phenylacetaldehyde as the principal components. Three solvents of different polarity were used for USE, and a total of 53 compounds were identified. The extracts with pentane/Et2O 1,:,2 (v/v) were the most representative for USE method containing the majority of the honey floral origin compounds and potential biomarkers (hexanol, acetic acid, butane-1,3-diol, butane-2,3-diol, benzoic acid, coumarin, and 2-phenylacetic acid). The total number of identified compounds (USE and HS-SPME) was 59. In general, the comparison with volatiles of other lavandin honeys of different geographic origins indicated several similarities, while acetic and formic acids were identified with high percentages in L. hybridaReverchon II honey. [source] A hybrid approach to Web forum interactional coherence analysisJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 8 2008Tianjun Fu Despite the rapid growth of text-based computer-mediated communication (CMC), its limitations have rendered the media highly incoherent. This poses problems for content analysis of online discourse archives. Interactional coherence analysis (ICA) attempts to accurately identify and construct CMC interaction networks. In this study, we propose the Hybrid Interactional Coherence (HIC) algorithm for identification of web forum interaction. HIC utilizes a bevy of system and linguistic features, including message header information, quotations, direct address, and lexical relations. Furthermore, several similarity-based methods including a Lexical Match Algorithm (LMA) and a sliding window method are utilized to account for interactional idiosyncrasies. Experiments results on two web forums revealed that the proposed HIC algorithm significantly outperformed comparison techniques in terms of precision, recall, and F-measure at both the forum and thread levels. Additionally, an example was used to illustrate how the improved ICA results can facilitate enhanced social network and role analysis capabilities. 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