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21.
The aim of this research was to determine whether all memory T cells have the same propensity to migrate to the joint in patients with juvenile idiopathic arthritis. Paired synovial fluid and peripheral blood mononuclear cell proliferative responses to a panel of antigens were measured and the results correlated with a detailed set of laboratory and clinical data from 39 patients with juvenile idiopathic arthritis. Two distinct patterns of proliferative response were found in the majority of patients: a diverse pattern, in which synovial fluid responses were greater than peripheral blood responses for all antigens tested; and a restricted pattern, in which peripheral blood responses to some antigens were more vigorous than those in the synovial fluid compartment. The diverse pattern was generally found in patients with a high acute phase response, whereas patients without elevated acute phase proteins were more likely to demonstrate a restricted pattern. We propose that an association between the synovial fluid T cell repertoire and the acute phase response suggests that proinflammatory cytokines may influence recruitment of memory T cells to an inflammatory site, independent of their antigen specificity. Additionally, increased responses to enteric bacteria and the presence of αEβ7 T cells in synovial fluid may reflect accumulation of gut associated T cells in the synovial compartment, even in the absence of an elevated acute phase response. This is the first report of an association between the acute phase response and the T cell population recruited to an inflammatory site.  相似文献   
22.
Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8%) were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the high prevalence and diversity of natural infections with trypanosomes in primates from Brazilian Amazon and were the first formal record of simian infections with trypanosomes in the State of Acre. The presence of T. cruzi-like and T. rangeli-like parasites are recorded in four new hosts.  相似文献   
23.
 Nucleotide sequences for the three exons of the β2-microglobulin (β2m) gene (B2m) were determined for 135 animals representing 37 species and all 16 genera of neotropical primates (Platyrrhini). Twenty-eight different nucleotide sequences, encoding for 26 different proteins, were obtained. In comparison with those of other primate species, the β2-microglobulins of the Platyrrhini form a distinct clade. Individual genera of neotropical primates have distinctive B2m sequences, but within a genera species can have either the same or different B2m sequences. B2m polymorphism was found within three of the species sampled: Callicebus personatus, Saguinus midas, and Aotus azarae. Of these only the polymorphism in A. azarae has an effect upon the mature, functional β2m protein: residue 4 being either alanine or threonine. The A. azarae B2m allele encoding alanine at position 4 is shared with another species of Aotus (A. infulatus). In pairwise comparison the mature β2m proteins of neotropical primates differ by 1–9 amino acid substitutions which can occur at 18 positions within the sequence. The substitutions are distributed throughout the primary structure but are more commonly found in loops rather than β strands of the tertiary structure. Of 17 residues of β2m which hydrogen-bond with the class I heavy chain in human MHC class I molecules, 13 are conserved in the neotropical primates. The overall pattern of sequence variation in the B2m genes of the Platyrrhini is consistent with an evolution by successive selectively neutral events. Received: 13 November 1997 / Revised: 12 January 1998  相似文献   
24.
The type and frequency of structural hemoglobin variants and their hematological and molecular characteristics were identified using PCR-RFLP and sequencing techniques in 66 individuals from 33 unrelated families who referred to the two clinics of Kermanshah University of Medical Sciences from 2005 to 2006. We detected 28 subjects carrier for Hb D-Punjab (42.4%), 21 individuals carrier of Hb Q-Iran (31.8%), 12 subjects heterozygous for Hb Setif (18.2%), four cases with sickle cell disease (6.1%), and one case with Hb C (1.5%). All βS genes (4 genes) were linked to the Benin haplotype with negative Taq I site 5′ to γA gene. All βD-Punjab genes (29 genes) were in linkage disequilibrium with haplotype I. The only βC chromosome was linked to haplotype II. Both β0-thalassemia chromosomes with CD15 (G → A) mutation had haplotype background I. Three β+-thalassemia chromosomes with IVSI.110 (G → A) mutation were associated with haplotype I [+ − − − − + +]. In turn, the three β-thalassemia chromosomes with IVS II.1 G → A mutation were associated with atypical haplotype [− + + + + + −]. Hematological indices of carriers of Hb D-Punjab, Hb Q-Iran and Hb Setif were lower than those reported for normal individuals. For the first time, we have reported the haplotype background of βS gene among Kurdish population of Iran. Our results revealed that Hb D-Punjab is the most prevalent β-globin chain structural variant in this area and that is followed in frequency by an α-chain variant, Hb Q-Iran. The result of present study is useful for clinical management and the establishment of screening programmes in Western Iran.  相似文献   
25.
What selection pressures drive the evolution of offspring size? Answering this fundamental question for any species requires an understanding of the relationship between offspring size and offspring fitness. A major goal of evolutionary ecologists has been to estimate this critical relationship, but for organisms with complex lifecycles, logistical constraints restrict most studies to early life‐history stages only. Here, we examine the relationship between offspring size and offspring performance in the field across multiple life‐history stages and across generations in a marine invertebrate .We then use these data to parameterise a simple optimality model to generate predictions of optimal offspring size and determined whether these predictions depended on which estimate of offspring performance was used. We found that offspring size had consistently positive effects on performance (estimated as post‐metamorphic growth, fecundity and reproductive output). We also found that manipulating the experience of offspring during the larval phase changed the way in which offspring size affects performance: offspring size affected post‐metamorphic growth when larvae were allowed to settle immediately but offspring size affected survival when larvae were forced to swim prior to settlement. Despite finding consistently positive effects of offspring size, early measures of the effect of offspring size resulted in the systematic underestimation of optimal offspring size. Surprisingly, the amount of variation in offspring performance that offspring size explained decreased with increasing time in the field but the steepness of the relationship between offspring size and performance actually increased. Our results suggest caution should be exercised when empirically examining offspring size effects – it may not be appropriate to assume that early measures are a good reflection of the actual relationship between offspring size and fitness.  相似文献   
26.
Erwinia Virulence Factor (Evf) has been identified in Erwinia carotovora carotovora 15 (Ecc15) as a virulence factor that promotes colonization of the Drosophila larval gut and provokes the triggering of a systemic immune response. Here we have analysed how Evf promotes persistence and colonization of bacteria inside the larval gut. Erwinia evf mutants do not persist in immune-deficient Drosophila, indicating that Evf does not act by counteracting immunity. The results indicated that Evf is not a toxin because various gram-negative bacteria expressing evf can persist without affecting viability of Drosophila larvae. Evf did not appear to be a factor antagonizing a host-specific reaction because in vitro assays failed to reveal detoxifying enzymatic activities against various compounds thought to contribute to the hostile environment of the gut. These findings were corroborated by the observation that Evf is not required for survival in midgut organ cultures. By contrast, bacteria expressing evf allow persistence in trans of bacteria lacking evf indicating that Evf promotes the accumulation of gram-negative bacteria in the anterior midgut by affecting gut physiology.  相似文献   
27.

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.  相似文献   
28.
In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.  相似文献   
29.
Originality measures how different a given species is from all other co‐occurring species regarding either their phylogenetic history or functional traits. Since it is important to preserve the various aspects of diversity and original species carry more phylogenetic or functional information, originality may be used to assign conservation priorities. Our goal was to evaluate the relationships between phylogenetic and functional originalities, and their simulated losses under extinction scenarios based on abundance, fire tolerance and habitat preference. We placed 100 plots in a cerrado reserve located in central Brazil, sampled all woody plants species within the plots, measured 14 functional traits and measured fire history. We assembled a phylogenetic tree and a functional dendrogram, with which we calculated the originalities. Phylogenetic‐ and functional‐based originalities were correlated. However, the loss of functional originality was different from random extinctions on the abundance and fire tolerance scenarios, whereas the loss of phylogenetic originality was not. When compared with phylogenetic originality, functional originality brought more information to be used in conservation strategies because it was sensitive to differences in species abundance and fire tolerance. Thus, the extinction of rare or fire‐sensitive species would result in important functional changes due to loss of distinctive traits.  相似文献   
30.

Background

A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.

Methods

FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.

Results

LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.

Conclusion

Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.
  相似文献   
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