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Cisplatin (CIS) is a potent chemotherapeutic agent primarily used to treat hematologic malignancies and solid tumors, including lymphomas, sarcomas, and some carcinomas. Patients receiving this treatment for tumors outside the nervous system develop cognitive impairment. Alterations in the kynurenine pathway (KP) following CIS treatment suggest that certain KP metabolites may cross the blood–brain barrier, leading to increased production of the neuromodulator kynurenic acid (KYNA), which is associated with cognitive impairment. This study aimed to evaluate the effects of modulating brain KYNA levels by the administration of N-acetylcysteine (NAC), an inhibitor of kynurenine aminotransferase II (KATII), an enzyme responsible for KYNA biosynthesis on the cognitive and neuromuscular deficits induced by CIS. Female Wistar rats were divided into four groups: control, NAC (300 mg/day/8 days), CIS (3 mg/kg i.p/5 days), and NAC + CIS (both treatments co-administered in parallel). Seven days after the last CIS administration, cognitive performance, muscle strength, brain KYNA levels, KATII activity, and brain tissue redox profile (lipid peroxidation and oxidized/reduced glutathione (GSH/GSSG) ratio) were assessed. CIS did not affect short-term memory but induced long-term memory deficits and reduced muscle strength, effects which were prevented by NAC co-administration. CIS decreased the GSH/GSSG ratio and the number of cells in the brain cortex while it increased lipid peroxidation, KYNA levels, and marginal KATII activity. All these effects were attenuated by the co-administration of NAC. These findings suggest that NAC mitigates the side effects of CIS, such as chemo-brain and muscle weakness, by improving the redox imbalance and modulating KYNA levels by limiting its non-enzymatic production by reactive oxygen species (ROS). [ABSTRACT FROM AUTHOR]

In heart failure (HF) patients undergoing cardiac surgery, an increased activity of mechanisms related to cardiac remodeling may determine a higher risk of postoperative atrial fibrillation (POAF). Given that atrial fibrillation (AF) has a negative impact on the course and management of HF, including the need for anticoagulation therapy, identifying the factors associated with AF occurrence after cardiac surgery is crucial for the prognosis of these patients. POAF is thought to occur when various clinical and biochemical triggers act on susceptible cardiac tissue (first hit), with oxidative stress and inflammation during cardiopulmonary bypass (CPB) surgery being potential contributing factors (second hit). However, the molecular mechanisms involved in these processes remain poorly characterized. Recent research has shown that patients who later develop POAF often have pre-existing abnormalities in calcium handling and activation of NLRP3-inflammasome signaling in their atrial cardiomyocytes. These molecular changes may make cardiomyocytes more susceptible to spontaneous Ca2+-releases and subsequent arrhythmias, particularly when exposed to inflammatory mediators. Additionally, some clinical studies have linked POAF with elevated preoperative inflammatory markers, but there is a need for further research in order to better understand the impact of CPB surgery on local and systemic inflammation. This knowledge would make it possible to determine whether patients susceptible to POAF have pre-existing inflammatory conditions or cellular electrophysiological factors that make them more prone to developing AF and cardiac remodeling. In this context, the NLRP3 inflammasome, expressed in cardiomyocytes and cardiac fibroblasts, has been identified as playing a key role in the development of HF and AF, making patients with pre-existing HF with reduced ejection fraction (HFrEF) the focus of several clinical studies with interventions that act at this level. On the other hand, HFpEF has been linked to metabolic and non-ischemic risk factors, but more research is needed to better characterize the myocardial remodeling events associated with HFpEF. Therefore, since ventricular remodeling may differ between HFrEF and HFpEF, it is necessary to perform studies in both groups of patients due to their pathophysiological variations. Clinical evidence has shown that pharmacological therapies that are effective for HFrEF may not provide the same anti-remodeling benefits in HFpEF patients, particularly compared to traditional adrenergic and renin–angiotensin–aldosterone system inhibitors. On the other hand, there is growing interest in medications with pleiotropic or antioxidant/anti-inflammatory effects, such as sodium–glucose cotransporter 2 inhibitors (SGLT-2is). These drugs may offer anti-remodeling effects in both HFrEF and HFpEF by inhibiting pro-inflammatory, pro-oxidant, and NLRP3 signaling pathways and their mediators. The anti-inflammatory, antioxidant, and anti-remodeling effects of SGLT-2 i have progressively expanded from HFrEF and HFpEF to other forms of cardiac remodeling. However, these advances in research have not yet encompassed POAF despite its associations with inflammation, oxidative stress, and remodeling. Currently, the direct or indirect effects of NLRP3-dependent pathway inhibition on the occurrence of POAF have not been clinically assessed. However, given that NLRP3 pathway inhibition may also indirectly affect other pathways, such as inhibition of NF-kappaB or inhibition of matrix synthesis, which are strongly linked to POAF and cardiac remodeling, it is reasonable to hypothesize that this type of intervention could play a role in preventing these events. [ABSTRACT FROM AUTHOR]

Epidemiological studies and meta-analyses have shown a strong association between high seroprevalence of Toxoplasma gondii (T. gondii) and schizophrenia. Schizophrenic patients showed higher levels of anti-Toxoplasma immunoglobulins M and G (IgM and IgG) when compared to healthy controls. Previously, in a rat model, we demonstrated that the progeny of mothers immunized with T. gondii lysates before gestation had behavioral and social impairments during adulthood. Therefore, we suggested that T. gondii infection can trigger autoreactivity by molecularly mimicking host brain proteins. Here, we aimed to identify the occurrence of antigenic mimicry between T. gondii epitopes and host brain proteins. Using a bioinformatic approach, we predicted T. gondii RH-88 B cell epitopes and compared them to human cell-surface proteins involved in brain development and differentiation (BrainS). Five different algorithms for B-cell-epitope prediction were used and compared, resulting in 8584 T. gondii epitopes. We then compared T. gondii predicted epitopes to BrainS proteins by local sequence alignments using BLASTP. T. gondii immunogenic epitopes significantly overlapped with 42 BrainS proteins. Among these overlapping proteins essential for brain development and differentiation, we identified HSP90 and NOTCH receptors as the proteins most likely to be targeted by the maternally generated pathogenic antibodies due to their topological overlap at the extracellular region of their sequence. This analysis highlights the relevance of pregestational clinical surveillance and screening for potential pathogenic anti-T. gondii antibodies. It also identifies potential targets for the design of vaccines that could prevent behavioral and cognitive impairments associated with pre-gestational T. gondii exposure. [ABSTRACT FROM AUTHOR]

La presente investigación tiene por objetivo realizar un análisis de nivel histórico-contable de las empresas mineras pertenecientes a la provincia de El Oro, para contribuir a la toma de decisiones a nivel Gerencial, la importancia de realizar este estudio es determinar las medidas, políticas normas contables adecuadas, para realizar prácticas productivas de manera sostenible con el medio ambiente, es así que, se seleccionó un método de investigación descriptivo con enfoque cualitativo, el caso se guio con un modelo transversal, es decir, la investigación se direcciono a un periodo de tiempo específico entre el 2017-2018. De esta forma se escogió como instrumento de extracción de datos una ficha de encuesta, para ello, en base a la muestra poblacional de 237 empresas mineras, se realizó en calculo Muestral, que dio como resultado 145 encuestas a aplicar, entre los principales resultados se describe que las empresas usan políticas contables basadas en las NIIF para llevar un control de registros contables.

The ancestral method of preparing chuño (freeze‐dried potato) involves three steps: freezing, soaking, and drying. The objective of this study is to identify the changes in microstructure, in physicochemical properties, and rheology of gels and suspensions of Andean potato starches caused by the procedure used to obtain chuño. A laboratory simulation of the procedure is performed using the potato variety "Rosadita" (Solanum tuberosum ssp. Andigenum). From the tests carried out on the starches extracted from the chuño obtained in the field and in the laboratory, differences phosphate content and gelatinization temperature are found. Marked differences are observed with respect to the control starch in the soluble amylose content, RVA profiles, textural attributes, and dynamic and viscous rheological properties. The chuño starches present greater resistance to granular breakdown. These observations suggest a different hydration, swelling, and gelation mechanism for the Rosadita and chuño starch samples compared to conventional potato starch and at the same time a modification due to the effect of freezing, which is more noticeable in the chuño obtained at −5 °C. [ABSTRACT FROM AUTHOR]

This study reflects on the idea of community of practice in a corpus of contemporary Latin American texts that address literary workshops as a learning space. Thus, it is intended to demonstrate how the idea of community of practice, such as that of pedagogical identity or repertoire, appears in contemporary texts as an established, recognisable practice and, in general, linked to the idea of an ignorant schoolmaster (Rancière). For this reason, the study reviews the classes of Hebe Uhart compiled by Liliana Villanueva; the chronicles of Villanueva on the workshops of renowned Latin American authors such as Abelardo Castillo and Liliana Heker; and essays by Tamara Kamenzsain, Fabián Casas, and Luis López-Aliaga. Lastly, the study highlights texts by prominent Latin American writers in which they reflect on the practice of writing as a community exercise of the creation of knowledge developed and reproduced by practitioners. [ABSTRACT FROM AUTHOR]