129 research outputs found

    An association between feather damaging behavior and corticosterone metabolite excretion in captive African grey parrots (Psittacus erithacus)

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    Background African grey parrots (Psittacus erithacus) are kept as pets and are frequently hand-reared. It has been observed that hand-reared African grey parrots may develop behavioral disorders such as feather damaging behavior (FDB). It is well known that chronic stress is involved in behavioral disorders in captive parrots. The main glucocorticoid in birds is corticosterone; its quantification provides information about adrenocortical activity and is considered to be a reliable indicator of stress levels in birds. We analyzed the differences in the excretion of corticosterone metabolites (CM) in the droppings of African grey parrots characterized by: 1. different rearing histories (parent rearing vs. hand rearing); and 2. the presence or absence of FDB in hand-reared parrots. Methods A total of 82 African grey parrots that were kept in captivity were considered. According to breeding methods, three groups of birds were defined: 1. The parent-reared (PR) parrots included birds kept in pairs (n = 30 pairs) with a conspecific partner of the opposite sex. All of these birds were healthy and never showed FDB signs; 2. The healthy hand-reared parrots (H-HR) included pet parrots individually kept, that were hand-reared and did not display any sign of FDB (n = 11, 7 males and 4 females); 3. The FDB hand-reared parrot (FDB-HR) included pet parrots individually kept, that were hand-reared and displayed FDB (n = 11, 7 males and 4 females). Droppings were collected in the morning over three alternating days in autumn 2014 and spring 2015. The CM were determined using a multi-species corticosterone enzyme immunoassay kit. Split-plot repeated-measure ANOVA was used to examine any differences using group, season and group × season as the main factors. Results Different quantities of CM in droppings were found for the three groups. The mean CM value was 587 ng/g in the PR parrots, 494 ng/g in the H-HR parrots and 1,744 ng/g in the FDB-HR parrots, irrespective of the season. The excretion of CM in FDB-HR was significantly higher than in PR or H-HR parrots. CM in droppings were not influenced by the season (autumn vs. spring); furthermore, the interaction between group and sampling season was not significant. Limited to the H-HR and FDB-HR groups, a trend in the significance of the difference in the mean CM excreted by male and female birds was observed, with the levels excreted by males being higher than those excreted by females. When the effect of age was considered (in the two separate groups), there was a statistically significant positive correlation only for H-HR. Conclusions The highest amount of CM excretion was found in FDB-HR parrots, and a positive correlation between age and CM excretion was found in H-HR. Given that the CM excretion of both PR and H-HR parrots was similar in our study, future research is recommended to investigate the specific aspects of hand-rearing to improve parrot welfare

    Identificación de parámetros de vehículos mediante dinámica de sistemas multicuerpo y el filtro de Kalman extendido (EKF)

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    Este artículo presenta el modelo multicuerpo de una furgoneta IVECO Daily 35C15 que ha sido desarrollado en Matlab™ con el objetivo de identificar los parámetros fundamentales necesarios para obtener una simulación dinámica lo más parecida posible a la realidad. Utiliza un método topológico semi-recursivo cuyas funciones críticas están programadas en C/C++ para mejorar su eficiencia. Se presentan los resultados obtenidos en la identificación utilizando como medidas reales, en un primer caso, los resultados de una simulación previa realizada con el mismo modelo matemático que utiliza el filtro y, después, medidas obtenidas de un ensayo realizado en la pista de pruebas del INSIA. El objetivo final del trabajo es validar el modelo de la furgoneta IVECO para poder utilizar dicho modelo en simulaciones más complejas

    Human T-Cell Leukemia Virus Type 1 Oncogenesis between Active Expression and Latency: A Possible Source for the Development of Therapeutic Targets

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    : The human T-cell leukemia virus type 1 (HTLV-1) is the only known human oncogenic retrovirus. HTLV-1 can cause a type of cancer called adult T-cell leukemia/lymphoma (ATL). The virus is transmitted through the body fluids of infected individuals, primarily breast milk, blood, and semen. At least 5-10 million people in the world are infected with HTLV-1. In addition to ATL, HTLV-1 infection can also cause HTLV-I-associated myelopathy (HAM/TSP). ATL is characterized by a low viral expression and poor prognosis. The oncogenic mechanism triggered by HTLV-1 is extremely complex and the molecular pathways are not fully understood. However, viral regulatory proteins Tax and HTLV-1 bZIP factor (HBZ) have been shown to play key roles in the transformation of HTLV-1-infected T cells. Moreover, several studies have shown that the final fate of HTLV-1-infected transformed Tcell clones is the result of a complex interplay of HTLV-1 oncogenic protein expression with cellular transcription factors that subvert the cell cycle and disrupt regulated cell death, thereby exerting their transforming effects. This review provides updated information on the mechanisms underlying the transforming action of HTLV-1 and highlights potential therapeutic targets to combat ATL

    Can a single low-intensity premature stimulus induce ventricular arrhythmias in the normal heart?

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    Previously, we observed that a single low-intensity premature ventricular stimulation could occasionally induce spontaneous ectopic beats in normal rat hearts. Possible hypothesis for the arrhythmia is that a premature beat can encounter a zone of conduction block to initiate reentry. However, enhanced dispersion of repolarization, a necessary condition for initiation of reentry, is unlikely to be present in normal myocardium. Thus, the main objective of the present study was to perform detailed pace mapping measurements in normal ventricular myocardium with a view to identify pacing sites and critical coupling intervals which could induce spontaneous ectopic beats and to characterize the reentrant circuits

    Feather picking in pet parrots: sensitive species, risk factor and ethological evidence

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    The goals of this study were to estimate the prevalence of feather picking (FP) in Italian pet parrots and evaluate the risk factors and possible ethological correlation. A web survey was created and addressed to owners of all species of companion parrots, distributed through on line parrots association websites, social networks and by mail. The survey was available for compilation from June to October 2014. In 292 compiled surveys, 20 different parrots genera were indicated; Psittacus spp. (24.3%), Agapornis spp. (19.5%), Nymphicus hollandicus (18.0%) and Amazona spp. (9.0%) were the most represented species. Our study showed a FP prevalence of 17.5%, with the highest prevalence in Agapornis spp. (26.3%) and Psittacus spp. (22.5%). Living with other parrots was positively associated to FP (p < 0.05), such as being fed in neonatal age and weaned by the breeder and not by the final owner (p < 0.001). Moreover, 2.9% of non-FP parrots and 10.0% of FP parrots lived always caged (p = 0.06). A significant difference in the feather picking site was detected (p < 0.001). The most affected body region was the chest (58.8%), followed by the rump (41.2%) and under wing regions (25.4%). At the same time, we conducted another study to better understand some information from the hand-raised parrots through a comparison with the parent-raised parrots. We recorded 1488 parent-raised parrots, and only 1.3% were affected by feather loss. This finding confirm that FP is be considered a multi-factorial behavioral pathology in which factors of different origin may cause behavioral disorders associated to self-injuries

    Arrhythmia susceptibility in senescent rat hearts

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    Cardiovascular disease increases with age as well as alterations of cardiac electrophysiological properties, but a detailed knowledge about changes in cardiac electrophysiology relevant to arrhythmogenesis in the elderly is relatively lacking. The aim of this study was to determine specific age-related changes in electrophysiological properties of the ventricles which can be related to a structural-functional arrhythmogenic substrate. Multiple epicardial electrograms were recorded on the ventricular surface of in vivo control and aged rats, while arrhythmia vulnerability was investigated by premature stimulation protocols. Single or multiple ectopic beats and sustained ventricular arrhythmias were frequently induced in aged but not in control hearts. Abnormal ventricular activation patterns during sinus rhythm and unchanged conduction velocity during point stimulation in aged hearts suggest the occurrence of impaired impulse conduction through the distal Purkinje system that might create a potential reentry substrate

    Thyroid hormone signaling is associated with physical performance, muscle mass, and strength in a cohort of oldest-old: results from the Mugello study.

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    Thyroid hormones (THs) play a crucial role in the homeostasis of muscle function, such as myogenesis and energy metabolism, suggesting that the thyroid may be also involved in the entropic processes of muscle aging. The aim of the present study is to evaluate the effect of TH signaling on physical performance, muscle mass, and strength in a cohort of community-dwelling oldest-old subjects (> 90 years). The study population was selected in a rural area of central Italy (Mugello, Tuscany), and the design was cross-sectional. Four hundred seventy-five subjects (130 males and 345 females) were enrolled, representing about 65% of all the nonagenarians living in the Mugello area. After adjusting for multiple confounding factors (sex, age, diabetes, and levothyroxine administration), the lowest quartile of FT3/FT4 ratio distribution showed lower physical performance compared to the other quartiles (β ± SE: - 0.49 ± 0.12; p < 0.001), whereas the highest quartile of FT3/FT4 ratio was associated with higher skeletal muscle index (β ± SE: 1.11 ± 0.42; p = 0.009). In addition, the lowest quartile of FT4 showed a statistically significant higher handgrip strength (β ± SE: 1.78 ± 0.68; p = 0.009) compared to all other quartiles. This study demonstrates that nonagenarians with higher FT3/FT4 ratios had better preserved muscle function, therefore successfully overcoming the imbalance of homeostatic and entropic processes involved in muscle aging. However, we could not establish a cause-effect relationship due to the cross-sectional design of the study

    Anti-vascular endothelial growth factor monotherapy or combined with verteporfin photodynamic therapy for retinal angiomatous proliferation: a systematic review with meta-analysis

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    : Purpose: To assess functional and anatomical outcomes of intravitreal anti-Vascular Endothelial Growth Factor (anti-VEGF) monotherapy versus combined with verteporfin Photodynamic Therapy (PDT) for Retinal Angiomatous Proliferation (RAP). Methods: Studies reporting outcomes of intravitreal anti-VEGF monotherapy and/or in combination with verteporfin PDT in RAP eyes with a follow-up ≥ 12&nbsp;months were searched. The primary outcome was the mean change in best corrected visual acuity (BCVA) at 12&nbsp;months. Mean change in central macular thickness (CMT) and mean number of injections were considered as secondary outcomes. The mean difference (MD) between pre- and post-treatment values was calculated along with 95% Confidence Interval (95% CI). Meta-regressions were performed to assess the influence of anti-VEGF number of injections on BCVA and CMT outcomes. Results: Thirty-four studies were included. A mean gain of 5.16 letters (95% CI = 3.30-7.01) and 10.38 letters (95% CI = 8.02-12.75) was shown in the anti-VEGF group and combined group, respectively (anti-VEGF group vs. combined group, p &lt; 0.01). A mean CMT reduction of 132.45&nbsp;µm (95% CI = from -154.99 to -109.90) and 213.93&nbsp;µm (95% CI = from -280.04 to -147.83) was shown in the anti-VEGF group and combined group, respectively (anti-VEGF group vs. combined group, p &lt; 0.02). A mean of 4.9 injections (95% CI = 4.2-5.6) and 2.8 injections (95% CI = 1.3-4.4) were administered over a 12-month period in the anti-VEGF group and combined group, respectively. Meta-regression analyses showed no influence of injection number on visual and CMT outcomes. High heterogeneity was found across studies for both functional and anatomical outcomes. Conclusion: A combined approach with anti-VEGF and PDT could provide better functional and anatomical outcomes in RAP eyes compared with anti-VEGF monotherapy

    Extracellular Vesicles Secreted by Mesenchymal Stromal Cells Exert Opposite Effects to Their Cells of Origin in Murine Sodium Dextran Sulfate-Induced Colitis

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    Several reports have described a beneficial effect of Mesenchymal Stromal Cells (MSCs) and of their secreted extracellular vesicles (EVs) in mice with experimental colitis. However, the effects of the two treatments have not been thoroughly compared in this model. Here, we compared the effects of MSCs and of MSC-EV administration in mice with colitis induced by dextran sulfate sodium (DSS). Since cytokine conditioning was reported to enhance the immune modulatory activity of MSCs, the cells were kept either under standard culture conditions (naïve, nMSCs) or primed with a cocktail of pro-inflammatory cytokines, including IL1β, IL6 and TNFα (induced, iMSCs). In our experimental conditions, nMSCs and iMSCs administration resulted in both clinical and histological worsening and was associated with pro-inflammatory polarization of intestinal macrophages. However, mice treated with iEVs showed clinico-pathological improvement, decreased intestinal fibrosis and angiogenesis and a striking increase in intestinal expression of Mucin 5ac, suggesting improved epithelial function. Moreover, treatment with iEVs resulted in the polarization of intestinal macrophages towards and anti-inflammatory phenotype and in an increased Treg/Teff ratio at the level of the intestinal lymph node. Collectively, these data confirm that MSCs can behave either as anti- or as pro-inflammatory agents depending on the host environment. In contrast, EVs showed a beneficial effect, suggesting a more predictable behavior, a safer therapeutic profile and a higher therapeutic efficacy with respect to their cells of origin.Fil: Tolomeo, Anna Maria. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; Italia. Università di Padova; Italia. Consorzio per la Ricerca Sanitaria; ItaliaFil: Castagliuolo, Ignazio. Università di Padova; ItaliaFil: Piccoli, Martina. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; ItaliaFil: Grassi, Michele. Università di Padova; ItaliaFil: Magarotto, Fabio. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; Italia. Università di Padova; ItaliaFil: De Lazzari, Giada. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; Italia. Consorzio per la Ricerca Sanitaria; Italia. Università di Padova; ItaliaFil: Malvicini, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentina. Consorzio per la Ricerca Sanitaria; Italia. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; ItaliaFil: Caicci, Federico. Università di Padova; ItaliaFil: Franzin, Chiara. Fondazione Istituto di Ricerca Pediatrica Città della Speranza; ItaliaFil: Scarpa, Melania. Veneto Institute of Oncology; ItaliaFil: Macchi, Veronica. Università di Padova; ItaliaFil: De Caro, Raffaele. Università di Padova; Italia. Consorzio Per la Ricerca Sanitaria; ItaliaFil: Angriman, Imerio. Università di Padova; ItaliaFil: Viola, Antonella. Università di Padova; ItaliaFil: Porzionato, Andrea. Consorzio Per la Ricerca Sanitaria; Italia. Università di Padova; ItaliaFil: Pozzobon, Michela. Fondazione Istituto Di Ricerca Pediatrica Città Della Speranza; Italia. Università di Padova; ItaliaFil: Muraca, Maurizio. Università di Padova; Italia. Consorzio Per la Ricerca Sanitaria; Italia. Fondazione Istituto Di Ricerca Pediatrica Città Della Speranza; Itali
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