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1.
Diego T. Tuero Vanina D. Fiorini Bettina Mahler Juan C. Reboreda 《Biological journal of the Linnean Society. Linnean Society of London》2013,110(2):442-448
Two possible patterns of bias in primary sex ratio have been proposed for size‐dimorphic brood parasites that do not evict host chicks: (1) larger males should be laid at greater frequency in hosts larger than the parasite because they compete better (increasing their survival) than females with large host nest‐mates, and (2) more costly males (i.e. the larger sex) should be laid at greater frequency in hosts smaller than the parasite because, in these hosts, parasite nestlings are provisioned at a higher rate and grow faster than in larger hosts. We tested these hypotheses in two hosts of the sexually size‐dimorphic shiny cowbird, Molothrus bonariensis, one smaller (house wren, Troglodytes aedon) and one larger (chalk‐browed mockingbird, Mimus saturninus) than the parasite. We measured: (1) sex ratio at laying; (2) development of sexual differences in body mass during the nestling stage; and (3) chick survival and sex ratio of chicks before fledging. In both hosts, we found sexual differences in body mass of nestlings from 7 days of age onwards, although we did not find a bias in the sex ratio of eggs laid and chicks fledged. The results of the present study do not support the hypothesis that shiny cowbird females benefit from biasing the primary sex ratio depending on the size of the hosts they parasitize. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 442–448. 相似文献
2.
Inhibition of the 3‐hydroxy‐3‐methyl‐glutaryl‐CoA reductase induces orofacial defects in zebrafish
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3.
Antonio Rodríguez-Poncelas Xavier Mundet-Tudurí Sonia Miravet-Jiménez Aina Casellas Joan F. Barrot-De la Puente Josep Franch-Nadal Gabriel Coll-de Tuero 《PloS one》2016,11(2)
Purpose
To explore the relationship between chronic kidney disease (CKD) and diabetic retinopathy (DR) in a representative population of type 2 diabetes mellitus (DM2) patients in Catalonia (Spain).Methods
This was a population-based, cross-sectional study. A total of 28,344 patients diagnosed with DM2 who had recorded ophthalmologic and renal functional examinations were evaluated. Data were obtained from a primary healthcare electronic database of medical records. CKD was defined as an estimated glomerular filtration ratio (eGFR) of <60 ml/min/1.73m2 and/or urine albumin to creatinine ratio (UACR) ≥30 mg/g. DR was categorized as non-vision threatening diabetic retinopathy and vision threatening diabetic retinopathy.Results
CKD was associated with a higher rate of DR [OR], 95% confidence interval [CI], 1.5 (1.4–1.7). When we analyzed the association between different levels of UACR and DR prevalence observed that DR prevalence rose with the increase of UACR levels, and this association was significant from UACR values ≥10 mg/g, and increased considerably with UACR values ≥300mg/g (Odds ratio [OR], 95% confidence interval [CI], 2.0 (1.6–2.5). This association was lower in patients with eGFR levels 44 to 30 mL/min/1.73m2 [OR], 95% confidence interval [CI], 1.3 (1.1–1.6).Conclusions
These results show that CKD, high UACR and/or low eGFR, appear to be associated with DR in this DM2 population. 相似文献4.
Tomasz Krzeszowski Krzysztof Przednowek Krzysztof Wiktorowicz Janusz Iskra 《Computer methods in biomechanics and biomedical engineering》2016,19(12):1319-1329
This paper presents a method of monocular human motion tracking for estimation of hurdle clearance kinematic parameters. The analysis involved 10 image sequences of five hurdlers at various training levels. Recording of the sequences was carried out under simulated starting conditions of a 110 m hurdle race. The parameters were estimated using the particle swarm optimization algorithm and they are based on analysis of the images recorded with a 100 Hz camera. The proposed method does not involve using any special clothes, markers, inertial sensors, etc. As the quality criteria, the mean absolute error and mean relative error were used. The level of computed errors justifies the use of this method to estimate hurdle clearance parameters. 相似文献
5.
Antoniak HL Snityns'kyĭ VV Babych NO Iskra RIa Buchko OM 《Ukrainski? biokhimicheski? zhurnal》1999,71(3):44-50
The age changes of enzymes of activity catalyzing several links of energy metabolism (hexokinase, phosphofructokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, NADP-isocitrate dehydrogenase, cytochrome c-oxidase) and antioxidant system (superoxide dismutase and glutathione reductase) in bone marrow myeloid cells and blood leukocytes of pig in the 10-day period after birth were investigated. The bone marrow cells and leukocytes of the new born piglets were characterized by low intensity of oxidative steps of energy metabolism as well as by low activity of antioxidant enzymes. In the period of neonatal adaptation reorganization of energy metabolism, particularly, intensification of oxidative processes in the investigated cells occurred. It included the pentose phosphate way and cytochrome c-oxidase activation. During the neonatal period of development the functional activity of antioxidant enzymes in the investigated cells of piglets increased. 相似文献
6.
Iskra Tuero Sandra Palma Franco Cabeza Sarah Saleemi Silvia Rodriguez Isidro Gonzales Holger Mayta Siddhartha Mahanty Hector H. Garcia Robert H. Gilman Cysticercosis Working Group in Perú 《PLoS neglected tropical diseases》2015,9(10)
Background
The ability of Taenia solium to modulate the immune system likely contributes to their longevity in the human host. We tested the hypothesis that the nature of the immune response is related to the location of parasite and clinical manifestations of infection.Methodology
Peripheral blood mononuclear cells (PBMC) were obtained from untreated patients with neurocysticercosis (NCC), categorized as having parenchymal or subarachnoid infection by the presence of cysts exclusively within the parenchyma or in subarachnoid spaces of the brain, and from uninfected (control) individuals matched by age and gender to each patient. Using multiplex detection technology, sera from NCC patients and controls and cytokine production by PBMC after T. solium antigen (TsAg) stimulation were assayed for levels of inflammatory and regulatory cytokines. PBMC were phenotyped by flow cytometry ex vivo and following in vitro stimulation with TsAg.Principal Findings
Sera from patients with parenchymal NCC demonstrated significantly higher Th1 (IFN-γ/IL-12) and Th2 (IL-4/IL-13) cytokine responses and trends towards higher levels of IL-1β/IL-8/IL-5 than those obtained from patients with subarachnoid NCC. Also higher in vitro antigen-driven TNF-β secretion was detected in PBMC supernatants from parenchymal than in subarachnoid NCC. In contrast, there was a significantly higher IL-10 response to TsAg stimulation in patients with subarachnoid NCC compared to parenchymal NCC. Although no differences in regulatory T cells (Tregs) frequencies were found ex vivo, there was a trend towards greater expansion of Tregs upon TsAg stimulation in subarachnoid than in parenchymal NCC when data were normalized for the corresponding controls.Conclusions/Significance
T. solium infection of the subarachnoid space is associated with an enhanced regulatory immune response compared to infection in the parenchyma. The resulting anti-inflammatory milieu may represent a parasite strategy to maintain a permissive environment in the host or diminish inflammatory damage from the host immune response in the central nervous system. 相似文献7.
Development of a modular virus clearance package for anion exchange chromatography operated in weak partitioning mode
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Timothy Iskra Ashley Sacramo Chris Gallo Ranga Godavarti Shuang Chen Scott Lute Kurt Brorson 《Biotechnology progress》2015,31(3):750-757
Anion exchange chromatography (AEX) operated under weak partitioning mode has been proven to be a powerful polishing step as well as a robust viral clearance step in Pfizer's monoclonal antibody (mAb) platform purification process. A multivariate design of experiment (DoE) study was conducted to understand the impact of operating parameters and feedstream impurity levels on viral clearance by weak partitioning mode AEX. Bacteriophage was used initially as a surrogate for neutral and acidic isoelectric point mammalian viruses (e.g., retrovirus and parvovirus). Five different mAbs were used in the evaluation of process parameters such as load challenge (both product and impurities), load pH, load conductivity, and contact time (bed height and flow‐rate). The operating ranges obtained from phage clearance studies and Pfizer's historical data were used to define an appropriate operating range for a subsequent clearance study with model retrovirus and parvovirus. Both phage and virus clearance evaluations included feedstreams containing different levels of impurities such as high molecular mass species (HMMS), host cell proteins (HCPs), and host cell DNA. For all the conditions tested, over 5 log10 of clearance for both retrovirus and parvovirus was achieved. The results demonstrated that weak partitioning mode AEX chromatography is a robust step for viral clearance and has the potential to be included as part of the modular viral clearance approach. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:750–757, 2015 相似文献
8.
R.J. Croft S. Leung R.J. McKenzie S.P. Loughran S. Iskra D.L. Hamblin N.R. Cooper 《Bioelectromagnetics》2010,31(6):434-444
The present study was conducted to determine whether adolescents and/or the elderly are more sensitive to mobile phone (MP)‐related bioeffects than young adults, and to determine this for both 2nd generation (2G) GSM, and 3rd generation (3G) W‐CDMA exposures. To test this, resting alpha activity (8–12 Hz band of the electroencephalogram) was assessed because numerous studies have now reported it to be enhanced by MP exposure. Forty‐one 13–15 year olds, forty‐two 19–40 year olds, and twenty 55–70 year olds were tested using a double‐blind crossover design, where each participant received Sham, 2G and 3G exposures, separated by at least 4 days. Alpha activity, during exposure relative to baseline, was recorded and compared between conditions. Consistent with previous research, the young adults' alpha was greater in the 2G compared to Sham condition, however, no effect was seen in the adolescent or the elderly groups, and no effect of 3G exposures was found in any group. The results provide further support for an effect of 2G exposures on resting alpha activity in young adults, but fail to support a similar enhancement in adolescents or the elderly, or in any age group as a function of 3G exposure. Bioelectromagnetics 31:434–444, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
9.
Stefanie Iskra Markus Kalla Henri-Jacques Delecluse Wolfgang Hammerschmidt Andreas Moosmann 《Journal of virology》2010,84(7):3612-3623
Epstein-Barr virus (EBV) efficiently drives proliferation of human primary B cells in vitro, a process relevant for human diseases such as infectious mononucleosis and posttransplant lymphoproliferative disease. Human B-cell proliferation is also driven by ligands of Toll-like receptors (TLRs), notably viral or bacterial DNA containing unmethylated CpG dinucleotides, which triggers TLR9. Here we quantitatively investigated how TLR stimuli influence EBV-driven B-cell proliferation and expression of effector molecules. CpG DNA synergistically increased EBV-driven proliferation and transformation, T-cell costimulatory molecules, and early production of interleukin-6. CpG DNA alone activated only memory B cells, but CpG DNA enhanced EBV-mediated transformation of both memory and naive B cells. Ligands for TLR2 or TLR7/8 or whole bacteria had a weaker but still superadditive effect on B-cell transformation. Additionally, CpG DNA facilitated the release of transforming virus by established EBV-infected lymphoblastoid cell lines. These results suggest that the proliferation of EBV-infected B cells and their capability to interact with immune effector cells may be directly influenced by components of bacteria or other microbes present at the site of infection.Epstein-Barr virus (EBV), a herpesvirus, is a very successful infectious agent: it establishes and maintains latent infection in >95% of human beings worldwide. This success is related to EBV''s varied strategies to maintain itself in its preferred host cell type, the B cell, by establishing different modes of latent infection (46). Some of these modes (latency modes 0, I, and II) are characterized by a resting B-cell phenotype and expression of a very limited set of EBV proteins (from none to four). In contrast, latency III involves the expression of at least 12 EBV latent-cycle gene products (10 proteins and 2 RNAs) (30, 31), which in their combined action profoundly alter the B cell''s appearance and behavior by inducing B-cell activation associated with proliferation, altered receptor expression, and cytokine secretion, as well as causing enhanced antigen presentation (31).In these various features, EBV infection of the latency III type resembles physiological activation of B cells in germinal centers even in its molecular details, because EBV closely mimics or constitutively activates some of the B cell''s main signaling pathways. Exogenous physiological signals leading to B-cell activation have been classified as “signal 1,” the stimulation of the B-cell receptor (BCR) by antigen binding; “signal 2,” the stimulation of CD40 by the CD40 ligand molecule, expressed on activated helper T cells; and “signal 3,” the stimulation of Toll-like receptors (TLRs) by microbial components, such as unmethylated CpG DNA, or their mimics. All three signals together are required for maximal proliferation of naive B cells (47). However, stimulation with TLR ligands alone, for example, CpG DNA, is sufficient to cause transient B-cell activation, including proliferation and induction of immune effector molecules such as CD86, a T-cell-costimulatory molecule (24). Additional immune effectors, the cytokines interleukin-6 (IL-6), IL-10, and IL-12, are induced when CpG stimulation is combined with strong CD40 stimulation (55).For primary infection of B cells, it is well established that EBV''s latent membrane proteins LMP2A (10, 39) and LMP1 (22) mimic signaling by the BCR and CD40, respectively. It is less clear whether and how EBV generates a potential signal 3 in the course of primary B-cell infection. A role of the TLR7 pathway has been proposed, based on the observation that EBV infection of naive B cells elevates the expression of TLR7 and its downstream signaling mediators (40). Additional mechanisms have recently been proposed to explain how EBV might trigger TLRs or other pattern recognition receptors in other cellular systems. For example, the Epstein-Barr virus-encoded small RNAs (EBERs) were described to trigger the retinoic acid-inducible gene I (RIG-I)-encoded protein, a receptor for various viral RNAs, in Burkitt''s lymphoma cells (48, 49). TLR2 signaling in monocytes is activated by binding of EBV particles to the cells (21) or by extracellular provision of EBV dUTPase (2).However, a physiologically relevant signal 3 need not originate in EBV itself. Other microbial agents present at the site of EBV infection might influence EBV infection, B-cell transformation, and virus release. For example, infectious mononucleosis (IM), a frequent consequence of primary EBV infection in adolescents and adults, is usually accompanied by tonsillitis with characteristic massive bacterial colonization (50), a likely source of TLR agonists acting on local EBV-infected B cells. Here we investigate the effects of CpG DNA and other exogenous TLR ligands on EBV-driven B-cell proliferation, clonal outgrowth, and induction of activation-associated cellular receptors and cytokines. 相似文献
10.
The unique ability of intrinsically disordered proteins (IDPs) to fold upon binding to partner molecules makes them functionally well-suited for cellular communication networks. For example, the folding-binding of different IDP sequences onto the same surface of an ordered protein provides a mechanism for signaling in a many-to-one manner. Here, we study the molecular details of this signaling mechanism by applying both Molecular Dynamics and Monte Carlo methods to S100B, a calcium-modulated homodimeric protein, and two of its IDP targets, p53 and TRTK-12. Despite adopting somewhat different conformations in complex with S100B and showing no apparent sequence similarity, the two IDP targets associate in virtually the same manner. As free chains, both target sequences remain flexible and sample their respective bound, natively -helical states to a small extent. Association occurs through an intermediate state in the periphery of the S100B binding pocket, stabilized by nonnative interactions which are either hydrophobic or electrostatic in nature. Our results highlight the importance of overall physical properties of IDP segments, such as net charge or presence of strongly hydrophobic amino acids, for molecular recognition via coupled folding-binding. 相似文献