953 resultados para family of origin
Resumo:
A 'two coat' model of the life cycle of Trypanosoma brucei has prevailed for more than 15 years. Metacyclic forms transmitted by infected tsetse flies and mammalian bloodstream forms are covered by variant surface glycoproteins. All other life cycle stages were believed to have a procyclin coat, until it was shown recently that epimastigote forms in tsetse salivary glands express procyclin mRNAs without translating them. As epimastigote forms cannot be cultured, a procedure was devised to compare the transcriptomes of parasites in different fly tissues. Transcripts encoding a family of glycosylphosphatidyl inositol-anchored proteins, BARPs (previously called bloodstream alanine-rich proteins), were 20-fold more abundant in salivary gland than midgut (procyclic) trypanosomes. Anti-BARP antisera reacted strongly and exclusively with salivary gland parasites and a BARP 3' flanking region directed epimastigote-specific expression of reporter genes in the fly, but inhibited expression in bloodstream and procyclic forms. In contrast to an earlier report, we could not detect BARPs in bloodstream forms. We propose that BARPs form a stage-specific coat for epimastigote forms and suggest renaming them brucei alanine-rich proteins.
Resumo:
The transcription factor PU.1 is essential for terminal myeloid differentiation, B- and T-cell development, erythropoiesis and hematopoietic stem cell maintenance. PU.1 functions as oncogene in Friend virus-induced erythroleukemia and as tumor suppressor in acute myeloid leukemias. Moreover, Friend virus-induced erythroleukemia requires maintenance of PU.1 expression and the disruption of p53 function greatly accelerates disease progression. It has been hypothesized that p53-mediated expression of the p21(Cip1) cell cycle inhibitor during differentiation of pre-erythroleukemia cells promotes selection against p53 function. In addition to the blockage of erythroblast differentiation provided by increased levels of PU.1, we propose that PU.1 alters p53 function. We demonstrate that PU.1 reduces the transcriptional activity of the p53 tumor suppressor family and thus inhibits activation of genes important for cell cycle regulation and apoptosis. Inhibition is mediated through binding of PU.1 to the DNA-binding and/or oligomerization domains of p53/p73 proteins. Lastly, knocking down endogenous PU.1 in p53 wild-type REH B-cell precursor leukemia cells leads to increased expression of the p53 target p21(Cip1).
Resumo:
BACKGROUND: The aortomitral continuity (AMC) has been described as a site of origin for ventricular tachycardias (VT) in structurally normal hearts. There is a paucity of data on the contribution of this region to VTs in patients with structural heart disease. METHODS AND RESULTS: Data from 550 consecutive patients undergoing catheter ablation for VT associated with structural heart disease were reviewed. Twenty-one (3.8%) had a VT involving the peri-AMC region (age, 62.7+/-11 years; median left ventricular ejection fraction, 43.6+/-17%). Structural heart disease was ischemic in 7 (33%), dilated cardiomyopathy in 10 (47.6%), and valvular cardiomyopathy in 4 (19%) patients, respectively. After 1.9+/-0.8 catheter ablation procedures (including 3 transcoronary ethanol ablations) the peri-AMC VT was not inducible in 19 patients. The remaining 2 patients underwent cryosurgical ablation. Our first catheter ablation procedure was less often successful (66.7%) for peri-AMC VTs compared with that for 246 VTs originating from the LV free wall (81.4%, P=0.03). During a mean follow-up of 1.9+/-2.1 years, 12 (57.1%) patients remained free of VT, peri-AMC VT recurred in 7 patients, and 1 patient had recurrent VT from a remote location. Three patients died. Analysis of 50 normal coronary angiograms demonstrated an early septal branch supplying the peri-AMC area in 58% of cases that is a potential target for ethanol ablation. CONCLUSIONS: VTs involving the peri-AMC region occur in patients with structural heart disease and appear to be more difficult to ablate compared with VTs originating from the free LV wall. This region provides unique challenges for radiofrequency ablation, but cryosurgery and transcoronary alcohol ablation appear feasible in some cases.
Resumo:
The present paper examines the syntactic and semantic properties of a group of constructions which carry an idiomatic interpretation of obtainment. In Polish and German, the constructions under consideration consist of a verb with a directional particle followed by an object NP, as exemplified in (1a)-(1b). (1a) Adam wynurkował starego buta. (Polish) Adam wy- snorkeled old shoe. ‘Adam found an old shoe while snorkeling.’ (1b) Michael erboxte sich den Titel. (German) Michael er- boxed REFL the title. ‘Michael boxed his way to the (championship) title.’ Sentences containing these constructions will be assumed to have the same basic interpretation “Subject obtains/produces Object by V-ing”. A constructional analysis of the constructions will be proposed, as they pose licensing problems and their interpretation cannot be accounted for in terms of the individual conceptual structures of the lexical items composing the sentence. Unlike most accounts of verb particle constructions based on implicit or explicit assumptions of straightforward semantic composition, the present study proposes an analysis under which the semantic structure of verb particle combinations is not a compositional function of the verb and the particle/prefix alone. It is argued that the construction comes with its own subcategorization frame (separate from that carried by the verb) which is motivated by the meaning of the construction and its corresponding constructional subevent. Additionally, a crosslinguistic correlation will be shown to hold between a language’s ability to express event conflation (Talmy 1985, 2000) and the occurrence of some form of the construction in that language. This will be taken as an indication of the resultative nature of those types of directional phrases which involve the semantic interpretation of boundary crossing.
Resumo:
This article examines the conditions under which a system of extended collective licensing (ECL) for the use of works contained in the collections of cultural heritage institutions (CHIs) participating in Europeana could function within a cross-border basis. ECL is understood as a form of collective rights management whereby the application of freely negotiated copyright licensing agreements between a user and a collective management organisation (“CMO”), is extended by law to non-members of the organisation. ECL regimes have already been put in place in a few Member States and so far, all have the ability to apply only on a national basis. This article proposes a mechanism that would allow works licensed under an ECL system in one territory of the European Union to be made available in all the territories of the Union. The proposal rests on the statutory recognition of the “country of origin” principle, as necessary and sufficient territory for the negotiation and application of an ECL solution for the rights clearance of works contained in the collection of a cultural heritage institution, including orphan works.
Resumo:
OBJECTIVES Smoking is related to income and education and contributes to social inequality in morbidity and mortality. Socialisation theories focus on one's family of origin as regards acquisition of norms, attitudes and behaviours. Aim of this study is to assess associations of daily smoking with health orientation and academic track in young Swiss men. Further, to assess associations of health orientation and academic track with family healthy lifestyle, parents' cultural capital, and parents' economic capital. METHODS Cross-sectional data were collected during recruitment for compulsory military service in Switzerland during 2010 and 2011. A structural equation model was fitted to a sample of 18- to 25-year-old Swiss men (N = 10,546). RESULTS Smoking in young adults was negatively associated with academic track and health orientation. Smoking was negatively associated with parents' cultural capital through academic track. Smoking was negatively associated with health orientation which in turn was positively associated with a healthy lifestyle in the family of origin. CONCLUSIONS Results suggest two different mechanisms of intergenerational transmissions: first, the family transmission path of health-related dispositions, and secondly, the structural transmission path of educational inequality.
Resumo:
This brief review of the human Na/H exchanger gene family introduces a new classification with three subgroups to the SLC9 gene family. Progress in the structure and function of this gene family is reviewed with structure based on homology to the bacterial Na/H exchanger NhaA. Human diseases which result from genetic abnormalities of the SLC9 family are discussed although the exact role of these transporters in causing any disease is not established, other than poorly functioning NHE3 in congenital Na diarrhea.
Resumo:
The SLC13 family comprises five genes (SLC13A1, SLC13A2, SLC13A3, SLC13A4, and SLC13A5) encoding structurally related multi-spanning transporters (8-13 transmembrane domains) with orthologues found in prokaryotes and eukaryotes. Mammalian SLC13 members mediate the electrogenic Na(+)-coupled anion cotransport at the plasma membrane of epithelial cells (mainly kidney, small intestine, placenta and liver) or cells of the central nervous system. While the two SLC13 cotransporters NaS1 (SLC13A1) and NaS2 (SLC13A4) transport anions such sulfate, selenate and thiosulfate, the three other SLC13 members, NaDC1 (SLC13A2), NaCT (SLC13A5) and NaDC3 (SLC13A3), transport di- and tri-carboxylate Krebs cycle intermediates such as succinate, citrate and α-ketoglutarate. All these transporters play a variety of physiological and pathophysiological roles in the different organs. Thus, the purpose of this review is to summarize the roles of SLC13 members in human physiology and pathophysiology and what the therapeutic perspectives are. We have also described the most recent advances on the structure, expression, function and regulation of SLC13 transporters.
Resumo:
Recent publications demonstrated that a fragment of a Neospora caninum ROP2 family member antigen represents a promising vaccine candidate. We here report on the cloning of the cDNA encoding this protein, N. caninum ROP2 family member 1 (NcROP2Fam-1), its molecular characterization and localization. The protein possesses the hallmarks of ROP2 family members and is apparently devoid of catalytic activity. NcROP2Fam-1 is synthesized as a pre-pro-protein that is matured to 2 proteins of 49 and 55 kDa that localize to rhoptry bulbs. Upon invasion the protein is associated with the nascent parasitophorous vacuole membrane (PVM), evacuoles surrounding the host cell nucleus and, in some instances, the surface of intracellular parasites. Staining was also observed within the cyst wall of 'cysts' produced in vitro. Interestingly, NcROP2Fam-1 was also detected on the surface of extracellular parasites entering the host cells and antibodies directed against NcROP2Fam-1-specific peptides partially neutralized invasion in vitro. We conclude that, in spite of the general belief that ROP2 family proteins are intracellular antigens, NcROP2Fam-1 can also be considered as an extracellular antigen, a property that should be taken into account in further experiments employing ROP2 family proteins as vaccines.