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OBJECTIVE: To evaluate the utility of low-cost simulation models to teach surgical techniques for placenta accreta spectrum (PAS), included in a multimodal education workshop for PAS. METHODS: This was an observational, survey-based study. Participants were surveyed before and after the use of low-fidelity mannequins to simulate two surgical techniques for PAS (one-step conservative surgery [OSCS] and modified subtotal hysterectomy [MSTH]), within a multimodal educational workshop. The workshops included pre-course preparation, didactics, simulated practice of the techniques using low-cost models, and viewing live surgery. RESULTS: Six OSCS/MSTH training workshops occurred across six countries and a total of 270 participants were surveyed. The responses of 127 certified obstetricians and gynecologists (OB-GYNs) were analyzed. Participants expressed favorable impressions of all components of the simulated session. Perceived anatomical simulator fidelity, scenario realism, educational component effectiveness, and self-assessed performance improvement received ratings of 4-5 (positive end of the Likert scale) from over 90% of respondents. When asked about simulation's role in technique comprehension, comfort level in technique performance, and likelihood of recommending this workshop to others, more than 75% of participants rated these aspects with a score of 4-5 (positively) on the five-point scale. CONCLUSION: Low-cost simulation, within a multimodal education strategy, is a well-accepted intervention for teaching surgical techniques for PAS.

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BACKGROUND: It has been previously demonstrated that the maintenance of ischemic acidic pH or the delay of intracellular pH recovery at the onset of reperfusion decreases ischemic-induced cardiomyocyte death. OBJECTIVE: To examine the role played by nitric oxide synthase (NOS)/NO-dependent pathways in the effects of acidic reperfusion in a regional ischemia model. METHODS: Isolated rat hearts perfused by Langendorff technique were submitted to 40 min of left coronary artery occlusion followed by 60 min of reperfusion (IC). A group of hearts received an acid solution (pH = 6.4) during the first 2 min of reperfusion (AR) in absence or in presence of l-NAME (NOS inhibitor). Infarct size (IS) and myocardial function were determined. In cardiac homogenates, the expression of P-Akt, P-endothelial and inducible isoforms of NOS (P-eNOS and iNOS) and the level of 3-nitrotyrosine were measured. In isolated cardiomyocytes, the intracellular NO production was assessed by confocal microscopy, under control and acidic conditions. Mitochondrial swelling after Ca2+ addition and mitochondrial membrane potential (Δψ) were also determined under control and acidosis. RESULTS: AR decreased IS, improved postischemic myocardial function recovery, increased P-Akt and P-eNOS, and decreased iNOS and 3-nitrotyrosine. NO production increased while mitochondrial swelling and Δψ decreased in acidic conditions. l-NAME prevented the beneficial effects of AR. CONCLUSIONS: Our data strongly supports that a brief acidic reperfusion protects the myocardium against the ischemia-reperfusion injury through eNOS/NO-dependent pathways.

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The Valle del Cauca region in Colombia is a significant producer of sugar cane, resulting in large quantities of agricultural residues (green harvesting residues (GHRs)). To ensure sustainable management of these residues, it is crucial to implement proper treatment and disposal technologies while also reusing waste to produce biogas, bioelectricity, or biofuels. The biomass hydrothermal carbonization process offers a means to convert these residues into useful products that serve as fuels or valuable energy materials. This thermal treatment involves the use of water as a solvent and reagent within the biomass's internal structure. In this study, sugar cane cutting residues were collected with relatively high moisture content of 8.5% wt. These residues were subjected to carbonization temperatures ranging from 200 to 300 °C, along with water/GHR ratios between 5/1 and 10/1. The properties of the resulting hydrocarbons were analyzed by using proximate and ultimate analysis. The objective was to produce hydrochar samples with the highest higher heating value (HHV) and energy density compared with the GHRs. The HHV value of the hydrochar showed a significant increase of 69.6% compared with that of the GHRs, reaching 43.5 MJ/kg. Besides, process parameters were optimized for mass yields, energy yields, and ash content. This exploration led us to investigate a new temperature range between 280 and 320 °C, allowing us to establish an optimal value for the hydrochar's properties.

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We report the draft genome sequences of four Morganella morganii strains isolated from the stools of four patients diagnosed with colorectal cancer (CRC) in Medellín, Colombia. These genomes represent an important addition to the limited number of genomes of M. morganii strains originating from CRC patients currently available.

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The Colombian sugarcane industry yields significant residues, categorized as agricultural and industrial. While bagasse, a widely studied industrial residue, is employed for energy recovery through combustion, agricultural residues are often left in fields. This study assesses the combustion behavior of these residues in typical collection scenarios. Additionally, it encompasses the characterization of residues from genetically modified sugarcane varieties in Colombia, potentially exhibiting distinct properties not previously documented. Non-isothermal thermogravimetrical analysis was employed to study the thermal behavior of sugarcane industrial residues (bagasse and pith) alongside agricultural residues from two different sugarcane varieties. This facilitated the determination of combustion reactivity through characteristic combustion process temperatures and technical parameters like ignition and combustion indexes. Proximate, elemental, and biochemical analyses revealed slight compositional differences. Agricultural residues demonstrated higher ash content (up to 34%) due to foreign matter adhering during harvesting, as well as soil and mud attachment during collection. Lignin content also varied, being lower for bagasse and pith, attributed to the juice extraction and milling processes that remove soluble lignin. Thermogravimetric analysis unveiled a two-stage burning process in all samples: devolatilization and char formation (~170°C), followed by char combustion (~310°C). Characteristic temperatures displayed subtle differences, with agricultural residues exhibiting lower temperatures and decomposition rates, resulting in reduced ignition and combustion indexes. This indicates heightened combustion reactivity in industrial residues, attributed to their elevated oxygen percentage, leading to more reactive functional groups and greater combustion stability compared to agricultural residues. This information is pertinent for optimizing sugarcane residues utilization in energy applications.

Weather in collection time affects composition of sugarcane agricultural residues.Combustion of sugarcane residues occurs over similar temperature ranges.Industrial residues are more reactive to combustion than agricultural residues.Overall thermal behavior of sugarcane residues depends on their composition.

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The hormone ghrelin displays several well-characterized functions, including some with pharmaceutical interest. The receptor for ghrelin, the growth hormone secretagogue receptor (GHSR), is expressed in the hypothalamic paraventricular nucleus (PVH), a critical hub for the integration of metabolic, neuroendocrine, autonomic, and behavioral functions. Here, we performed a neuroanatomical and functional characterization of the neuronal types mediating ghrelin actions in the PVH of male mice. We found that fluorescent ghrelin mainly labels PVH neurons immunoreactive for nitric oxide synthase 1 (NOS1), which catalyze the production of nitric oxide [NO]). Centrally injected ghrelin increases c-Fos in NOS1 PVH neurons and NOS1 phosphorylation in the PVH. We also found that a high dose of systemically injected ghrelin increases the ghrelin level in the cerebrospinal fluid and in the periventricular PVH, and induces c-Fos in NOS1 PVH neurons. Such a high dose of systemically injected ghrelin activates a subset of NOS1 PVH neurons, which do not express oxytocin, via an arcuate nucleus-independent mechanism. Finally, we found that pharmacological inhibition of NO production fully abrogates ghrelin-induced increase of calcium concentration in corticotropin-releasing hormone neurons of the PVH whereas it partially impairs ghrelin-induced increase of plasma glucocorticoid levels. Thus, plasma ghrelin can directly target a subset of NO-producing neurons of the PVH that is involved in ghrelin-induced activation of the hypothalamic-pituitary-adrenal neuroendocrine axis.

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We characterize Trypanosoma cruzi infections from blood and cerebrospinal fluid samples in a case series of people with human immunodeficiency virus and Chagas disease. We identify different infecting T. cruzi populations, highlighting the usefulness of real-time polymerase chain reaction for Chagas disease reactivation diagnosis and evaluation of treatment response.

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NEW FINDINGS: What is the central question of this study? Do alterations in thyroid status affect haemodynamic parameters and echocardiographic measurements in the rat postnatal heart, and calcium handling, contractility, relaxation and cardiolipin content in isolated rat cardiomyocytes? What is the main finding and its importance? An imbalance in phospholipids of the mitochondrial membrane such as cardiolipin is related to defects in mitochondrial function. T3 -dependent cardiolipin signals contribute to the maintenance of mitochondrial homeostasis and involve Ca2+ handling, this pathway being more important in hypothyroidism. ABSTRACT: The objective of this study was to evaluate whether alterations in thyroid status affect (1) haemodynamic parameters and echocardiographic measurements in the rat postnatal heart, and (2) calcium handling, contractility, relaxation and cardiolipin content in isolated rat cardiomyocytes. Sprague-Dawley rats aged 2 months treated with T3 (hyperthyroid, 20 µg/100 g body weight) or 0.02% methimazole (hypothyroid, w/v) for 28 days. Heart function was evaluated by echocardiography. Measurements of mean arterial pressure (MAP), heart rate, Ca2+ transients, cardiomyocyte shortening, number of spontaneous contractions per minute and cardiolipin (CL) content were performed. Thyroid disorders were associated with changes in pacemaker activity without modifications of MAP. Thyroid disorder induced changes in left ventricular diameter which were correlated with modifications of cardiac contractility (altered cell shortening and sarcoplasmic reticulum Ca2+ content). Endocrine disorders altered cardiomyocyte relaxation (reduction in the time to 50% re-lengthening and the time to 50% Ca2+ decay). Thyroid disorder increased the number of spontaneous contractions per minute (an index of pro-arrhythmogenic behaviour). CL content was increased only in hypothyroid rats. Changes in CL content, CL composition and CL-protein interaction in mitochondria from hypothyroid animals are responsible for alterations of contractile and relaxation cardiac function. This mechanism may be not be involved in T3 -treated rats. Maintenance of euthyroidism is of crucial importance to preserve cardiac performance. An imbalance in relation to phospholipids of the mitochondrial membrane such as CL is related to defects in mitochondrial function. T3 -dependent CL signals contribute to the maintenance of mitochondrial homeostasis and involve Ca2+ handling, this pathway being more important in hypothyroidism.

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At the beginning of 2020, the pandemic caused by the SARS-CoV-2 virus led to the fast sequencing of its genome to facilitate molecular engineering strategies to control the pathogen's spread. The spike (S) glycoprotein has been identified as the leading therapeutic agent due to its role in localizing the ACE2 receptor in the host's pulmonary cell membrane, binding, and eventually infecting the cells. Due to the difficulty of delivering bioactive molecules to the intracellular space, we hypothesized that the S protein could serve as a source of membrane translocating peptides. AHB-1, AHB-2, and AHB-3 peptides were identified and analyzed on a membrane model of DPPC (dipalmitoylphosphatidylcholine) using molecular dynamics (MD) simulations. An umbrella sampling approach was used to quantify the energy barrier necessary to cross the boundary (13.2 to 34.9 kcal/mol), and a flat-bottom pulling helped to gain a deeper understanding of the membrane's permeation dynamics. Our studies revealed that the novel peptide AHB-1 exhibited comparable penetration potential of already known potent cell-penetrating peptides (CPPs) such as TP2, Buforin II, and Frenatin 2.3s. Results were confirmed by in vitro analysis of the peptides conjugated to chitosan nanoparticles, demonstrating its ability to reach the cytosol and escape endosomes, while maintaining high biocompatibility levels according to standardized assays.

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This study presents the application of a novel approach, using thermal and optical techniques, to identify the causes of poor burnout performance of Colombian stoker furnaces in the Cauca Valley State. The four coals used in these furnaces were characterized to obtain particle size distribution, particle and tapped density, elemental and proximate composition, mineral composition, and maceral content. Up to 80% incomplete combustion was noted in macro-TGA tests compared to complete combustion in a micro-TGA. Reflectance and intrinsic reactivity measurements were for chars prepared in three different particle sizes (<6, 6-19, and 19 mm), three temperatures (700, 900, and 1050 °C), and three residence times (10, 30, and 120 min). Two of the coals produced char samples with reflectance values above 6%, which matched those seen in the stoker, indicating that the furnace temperature was not the cause of poor combustion and that only two of the four coals were likely to be present in the furnace bottom ash. These tests were also able to prove that oxygen diffusion limitation was the root cause of the poor burnout where the carbon inside the furnace bottom ash was shielded from oxygen ingress through the formation of a nonpermeable slag layer. Thus, this study demonstrates the potential of both thermal profiling and optical reflectance as a tool for forensically evaluating the thermal history and operational performance of furnaces.