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1.
Parasitol Int ; 103: 102954, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39181313

RESUMO

The present report describes a case of acanthocephaliasis associated with necrotic enteritis in quetzals (Pharomachrus mocinno). Three juvenile quetzals exhibited depression, anorexia, ruffled feathers, and sudden death. They were submitted to the laboratory for examination. The birds had hatched and lived in captivity in an aviary in Mexico. Gross lesions observed were hemorrhagic, fibrinoid necrotic enteritis, with acanthocephalans adhered to the intestinal mucosa. The specimens were identified by parasitology, electronic microscopy, and molecular biology as Plagiorhynchus (Prosthorhynchus) sp. Lesions compatible with necrotic enteritis were also confirmed by isolation and genotyping of Clostridium perfringens type E. This is the first report of Plagiorhynchus (Prosthorhynchus) sp. in quetzals in captivity in Mexico. The findings in this manuscript suggest that this parasite could be a predisposing factor for necrotic enteritis as well as a risk component in the breeding programs and survival of this avian species in captivity.


Assuntos
Acantocéfalos , Doenças das Aves , Enterite , Helmintíase Animal , Necrose , Animais , Doenças das Aves/parasitologia , Enterite/veterinária , Enterite/parasitologia , Necrose/veterinária , Helmintíase Animal/parasitologia , México , Clostridium perfringens/isolamento & purificação , Masculino
2.
N Biotechnol ; 82: 1-13, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-38615946

RESUMO

This work proposes a new data-driven model to estimate and predict pH dynamics in freshwater raceway photobioreactors. The resulting model is based purely on data measured from the reactor and divides the pH dynamics into two different behaviors. One behavior is described by the variation of pH due to the photosynthesis phenomena made by microalgae; and the other comes from the effect of CO2 injections into the medium for control purposes. Moreover, it was observed that the model parameters vary throughout the day depending on the weather conditions and reactor status. Thus, a decision tree algorithm is also developed to capture the parameter variation based on measured variables of the system, such as solar radiation, medium temperature, and medium level. The proposed model has been validated for a data set of more than 100 days during 10 months in a semi-industrial raceway reactor, covering a wide range of weather and system scenarios. Additionally, the proposed model was used to design an adaptive control algorithm which was also experimentally tested and compared with a classical fixed parameter control approach.


Assuntos
Microalgas , Microalgas/metabolismo , Microalgas/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Fotobiorreatores , Algoritmos , Reatores Biológicos , Modelos Biológicos , Fotossíntese
3.
Methods Mol Biol ; 2795: 169-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38594538

RESUMO

DNA methylation and posttranslational modifications of histones instruct gene expression in eukaryotes. Besides canonical histones, histone variants also play a critical role in transcriptional regulation. One of the best studied histone variants in plants is H2A.Z whose removal from gene bodies correlates with increased transcriptional activity. The eviction of H2A.Z is regulated by environmental cues such as increased ambient temperatures, and current models suggest that H2A.Z functions as a transcriptional buffer preventing environmentally responsive genes from undesired activation. To monitor temperature-dependent H2A.Z dynamics, chromatin immunoprecipitation (ChIP) of H2A.Z-occupied DNA can be performed. The following protocol describes a quick and easy ChIP approach to study in vivo H2A.Z occupancy.


Assuntos
Regulação da Expressão Gênica , Histonas , Histonas/genética , Histonas/metabolismo , Imunoprecipitação da Cromatina , Metilação de DNA , Temperatura , Cromatina/genética , Nucleossomos
4.
Molecules ; 29(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276569

RESUMO

The production of human recombinant proteins to be used for therapeutic or nutritional purposes must focus on obtaining a molecule that is as close as possible to the native human protein. This biotechnological tool has been documented in various studies published in recent decades, with lactoferrin being one of those that has generated the most interest, being a promising option for recombinant technology. However, stability studies including thermodynamic parameters have not been reported for recombinant lactoferrin (Lf). The objective of this work was to obtain the human recombinant protein using the yeast Komagataella phaffii to study structural changes modifying pH and temperature using circular dichroism spectroscopy (CD). Thermodynamic parameters such as ΔH, ΔS and Tm were calculated and compared with commercial human lactoferrin. We propose the potential use of CD and thermodynamic parameters as a criterion in the production of recombinant proteins to be used in the production of specialized recombinant proteins.


Assuntos
Lactoferrina , Humanos , Lactoferrina/química , Dicroísmo Circular , Proteínas Recombinantes/metabolismo , Temperatura , Concentração de Íons de Hidrogênio
5.
Interface Focus ; 13(6): 20230030, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38106920

RESUMO

Metabolic syndrome (MetS) has been linked to a higher prevalence of cardiac arrhythmias, the most frequent being atrial fibrillation, but the mechanisms are not well understood. One possible underlying mechanism may be an abnormal modulation of autonomic nervous system activity, which can be quantified by analysing heart rate variability (HRV). Our aim was to investigate the modifications of long-term HRV in an experimental model of diet-induced MetS to identify the early changes in HRV and the link between autonomic dysregulation and MetS components. NZW rabbits were randomly assigned to control (n = 10) or MetS (n = 10) groups, fed 28 weeks with high-fat, high-sucrose diet. 24-hour recordings were used to analyse HRV at week 28 using time-domain, frequency-domain and nonlinear analyses. Time-domain analysis showed a decrease in RR interval and triangular index (Ti). In the frequency domain, we found a decrease in the low frequency band. Nonlinear analyses showed a decrease in DFA-α1 and DFA-α2 (detrended fluctuations analysis) and maximum multiscale entropy. The strongest association between HRV parameters and markers of MetS was found between Ti and mean arterial pressure, and Ti and left atrial diameter, which could point towards the initial changes induced by the autonomic imbalance in MetS.

6.
Heliyon ; 9(11): e22305, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034769

RESUMO

In the present work, the impact that the longitudinal shape of channels has on the current produced in the flow of a magneto-hydrodynamic microgenerator (MHDMG) is studied. The goal is to find the micro-channel geometry via modeling to maximize the current output for low Reynolds and Mach regimes. To carry out this study, a 3D dynamic numerical tool relying on the finite volume method was handled with the open-source software OpenFOAM. It is the base model to study the impact of intricate geometries on the ability to produce energy. An additional steady-state 2D analytical model was also developed to check some basic modeling assumptions. Both models have been experimentally validated on the simplest flow system having a constant square cross-section throughout. The results produced by both models cross-check very well and compare favorably with respect to experimental data. Hence, using the validated numerical tool, three shapes have been further investigated, namely, progressive (linear decrease of the cross-section), arc (parabolic decrease of the cross-section), and wavy (sinusoidal shape). It was found that the arc channel provides the greatest current output for the same volumetric flow. It is therefore the preferred choice for developing high current gain and more efficient MHDMG used in micro-scaled actuators and sensors.

7.
J Card Fail ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37907150

RESUMO

BACKGROUND: Primary graft dysfunction (PGD) is the leading cause of morbidity and mortality early after heart transplantation (HT). The International Consortium on PGD is a multicenter collaboration dedicated to identifying the clinical risk factors for PGD in the contemporary era of HT. The objectives of the current report were (1) to assess the incidence of severe PGD in an international cohort; (2) to evaluate the performance of the most strongly validated PGD risk tool, the RADIAL score, in a contemporary cohort; and (3) to redefine clinical risk factors for severe PGD in the current era of HT. METHODS: This is a retrospective, observational study of consecutive adult HT recipients between 2010 and 2020 in 10 centers in the United States, Canada and Europe. Patients with severe PGD were compared to those without severe PGD (comprising those with no, mild and moderate PGD). The RADIAL score was calculated for each transplant recipient. The discriminatory power of the RADIAL score was evaluated using receiver operating characteristic (ROC) analysis, and its calibration was assessed by plotting the percentage of PGD predicted vs that which was observed. To identify clinical risk factors associated with severe PGD, we performed multivariable mixed-effects logistic regression modeling to account for among-center variability. RESULTS: A total of 2746 patients have been enrolled in the registry to date, including 2015 (73.4%) from North America, and 731 (26.6%) from Europe; 215 participants (7.8%) met the criteria for severe PGD. There was an increase in the incidence of severe PGD over the study period (P value for trend by difference sign test = 0.004). The Kaplan-Meier estimate for 1-year survival was 75.7% (95% CI 69.4-80.9%) in patients with severe PGD as compared to 94.4% (95% CI 93.5-95.2%) in those without severe PGD (log-rank P value < 0.001). The RADIAL score performed poorly in our contemporary cohort and was not associated with severe PGD; it had an AUC of 0.53 (95% CI 0.48-0.58). In the multivariable regression model, acute preoperative dialysis (OR 2.41, 95% CI 1.31-4.43), durable left ventricular assist device support (OR 1.77, 95% CI 1.13-2.77), and total ischemic time (OR 1.20 for each additional hour, 95% CI 1.02-1.41) were associated with an increased risk of severe PGD. CONCLUSIONS: Our consortium has identified an increasing incidence of PGD in the modern transplant era. We identified contemporary risk factors for this early post-transplant complication, which confers a high mortality risk. These results may enable the identification of patients at high risk for developing severe PGD in order to inform peri-transplant donor and recipient management practices.

9.
N Biotechnol ; 77: 58-67, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37467926

RESUMO

In this work, a model for the characterization of microalgae cultures based on artificial neural networks has been developed. The characterization of microalgae cultures is essential to guarantee the quality of the biomass, and the objective of this work is to achieve a simple and fast method to address this issue. Data acquisition was performed using FlowCam, a device capable of capturing images of the cells detected in a culture sample, which are used as inputs by the model. The model can distinguish between 6 different genera of microalgae, having been trained with several species of each genus. It was further complemented with a classification threshold to discard unwanted objects while improving the overall accuracy of the model. The model achieved an accuracy of up to 97.27% when classifying a culture. The results demonstrate the effectiveness of the Deep Learning models for the characterization of microalgae cultures, it being a useful tool for the monitoring of microalgae cultures in large-scale production facilities while providing accurate characterization over a wide range of genera.


Assuntos
Inteligência Artificial , Microalgas , Redes Neurais de Computação , Biomassa
10.
O.F.I.L ; 33(2)Abril-Junio 2023.
Artigo em Espanhol | IBECS | ID: ibc-223834

RESUMO

En este artículo se presentan los resultados y la evaluación del focus group con farmacéuticos realizado en el colegio Oficial de Farmacéuticos de Madrid, como parte del proyecto “Igualdad y no discriminación en la atención farmacéutica a personas transexuales en España. Elaboración de un libro blanco”. El focus group ha permitido detectar actitudes, comportamientos y opiniones de los farmacéuticos comunitarios, evidenciándose el desconocimiento de numerosos aspectos relacionados con la realidad transexual, lo que lleva a pensar que se requiere de una formación adecuada del farmacéutico, tanto en los aspectos farmacológicos, como humanos y de comunicación. Sin embargo, no hay ninguna duda de que el farmacéutico comunitario, por su accesibilidad y cercanía, es un elemento de vital importancia para el asesoramiento, acompañamiento y ayuda de las personas transexuales y, en su caso, de sus familiares. (AU)


This article presents the results and the evaluation of the focus group with pharmacists carried out at the Official College of Pharmacists of Madrid, as part of the project “Equality and non-discrimination in pharmaceutical care for transgender people in Spain. Preparation of a white book”. The focus group has made it possible to detect attitudes, behaviors and opinions of community pharmacists, evidencing the ignorance of numerous aspects related to the transsexual reality, which leads to think that adequate training of the pharmacist is required, in both pharmacological aspects, as well as human and communication. However, there is no doubt that the community pharmacist, due to its accessibility and proximity, is an element of vital importance for the advice, accompaniment and help of transsexual people and, where appropriate, their families. (AU)


Assuntos
Humanos , Farmacêuticos , Farmácias , Pessoas Transgênero , Espanha , Grupos Focais
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