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ABSTRACT Objective: The objective of this study was to establish the genotype-phenotype correlation between karyotype results and the neurological and psychiatric alterations presented in patients with Turner syndrome (TS). Methods: A retrospective study was conducted on the medical records of 10/140 patients with TS and neurophysiological abnormalities seen at a university hospital in southern Brazil. In addition, a literature review spanning the period from January 1, 2012 to January 1, 2023 was carried out using the PubMed and Virtual Health Library databases. Results: Our study showed a potential correlation between neurological and psychiatric alterations in patients with TS. These findings are in accordance with those described in literature such as a high prevalence of learning or intellectual disabilities. However, our sample found more seizure episodes than those reported in other studies. Conclusions: The correlation established could be due to X chromosome dose-effect, as the review suggests that sex chromosome number and hormonal development can be associated with verbal, social, and cognitive skills or impairments.

RESUMO Objetivo: O objetivo deste estudo foi realizar a correlação genótipo-fenótipo entre os resultados de cariótipos e as alterações neurológicas e psiquiátricas apresentadas em pacientes com síndrome de Turner (ST). Métodos: Um estudo retrospectivo foi conduzido nos registros médicos de 10/140 pacientes com ST e deficiências neuropsicológicas atendidos pelo Serviço de Genética Clínica de um hospital do sul do Brasil. Ademais, uma revisão foi realizada pelas plataformas científicas PubMed e Biblioteca Virtual em Saúde (BVS) de artigos publicados entre 1o de janeiro de 2012 e 1o de janeiro de 2023. Foram selecionados 14 artigos em uma análise em duas etapas. Resultados: Nossa pesquisa mostrou potencial correlação entre alterações neurológicas e psiquiátricas em pacientes com ST. Esses achados corroboram os descritos por outros autores — como a elevada prevalência de dificuldades de aprendizagem ou intelectuais. Entretanto, nossa amostra encontrou mais episódios convulsivos do que os descritos em outros estudos. Conclusões: A correlação estabelecida pode ser devida ao efeito dose-dependente do cromossomo X, visto que nossa revisão sugere que o número de cromossomos sexuais ou o desenvolvimento hormonal está associado a habilidades ou deficiências verbais, sociais e cognitivas.

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ABSTRACT Purpose: This study aimed to evaluate the morphometric and volumetric dimensions of the lacrimal gland in patients with inactive thyroid eye disease and compare them with the values reported in the literature. Methods: This case series evaluated consecutive patients with inactive thyroid eye disease treated at a tertiary eye hospital from 2015 to 2020. The patients' baseline demographics and clinical characteristics were obtained. The axial and coronal length, width, and volume of the lacrimal gland were measured on computed tomography scan images, and the results were statistically analyzed. Results: A total of 21 patients (42 orbits) with inactive thyroid eye disease were evaluated. Their mean age was 49.0 ± 14.6 years, and 12 (57.1%) of them were men. The main complaint was dryness, and the majority of the patients had good vision and mild proptosis. The mean axial length and width of the lacrimal gland were 19.3 ± 3.9 mm and 7.5 ± 2.1 mm, respectively; coronal length and width, 20.4 ± 4.5 mm and 7.5 ± 2.1 mm, respectively; and lacrimal gland volume, 0.825 ± 0.326 mm3. Age, sex, or laterality were not found to be determinants of lacrimal gland enlargement. Conclusion: Patients with thyroid eye disease have enlarged lacrimal gland even in the nonactive phase of the disease multifactorial aspects influence the lacrimal gland in thyroid eye disease, making it difficult to establish a clear correlation with predisposing factors. Further studies are warranted to better understand the association between thyroid eye disease and the lacrimal gland.

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Context: An acidic hydrogen potential (pH) in an inflammatory condition in the periapical tissues may affect the properties of repair bioceramic cement. Aims: The aim of this study was to evaluate the effect of pH on the volumetric change of the ready-to-use bioceramic NeoPUTTY (NP) compared to the powder/liquid MTA Repair HP (MTAHP) after immersion in butyric acid (BA, pH 4.1) or phosphate-buffered saline (PBS, pH 7.35). Subjects and Methods: Dentin tubes filled with NP or MTAHP were scanned in micro-computed tomography (micro-CT) after 24 h. Then, the specimens were immersed in 1.5 mL of BA: NP/BA, MTAHP/BA or PBS: NP/PBS, MTAHP/PBS. After 7 days, new micro-CT scans were performed. The percentage of volumetric change (extremities and internal part) of the materials was assessed. Statistical Analysis Used: ANOVA/Tukey and Kruskal-Wallis tests were performed (α =0.05). Results: All materials showed a volumetric decrease after immersion in BA or PBS at the extremities in contact with the solutions. MTAHP/BA showed the highest volumetric loss. There was no difference in the volumetric change when the internal part of the materials was evaluated. Conclusions: An acid pH negatively affects the volumetric stability of MTAHP. Low values of volumetric change were demonstrated for NP in both immersion environments.

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PURPOSE: This study aimed to investigate the predictive value of intratumoral and peritumoral radiomics model for the cribriform component (CC) of invasive lung adenocarcinoma (LUAD). MATERIALS AND METHODS: The 144 patients with invasive LUAD from our center were randomly divided into training set (n = 100) and internal validation set (n = 44) in a ratio of 7:3, and 75 patients from center 2 were regarded as the external validation set. Clinical risk factors were examined using univariate and multivariate logistic regression to construct the clinical model. We extracted radiomics features from gross tumor volume (GTV), gross and peritumoral volume (GPTV), and peritumoral volume (PTV), respectively. Radiomics models were constructed with selected features. A combined model based on the optimal Radscore and clinically independent predictors was constructed, and its predictive performance was assessed by receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). RESULTS: The area under curves (AUCs) of the GTV model were 0.882 (95% CI 0.817-0.948), 0.794 (95% CI 0.656-0.932), and 0.766 (95% CI 0.657-0.875) in the training, internal validation, and external validation sets, and the PTV model had AUCs of 0.812 (95% CI 0.725-0.899), 0.749 (95% CI 0.597-0.902), and 0.670 (95% CI 0.543-0.798) in the training, internal validation, and external validation sets, respectively. However, the GPTV radiomics model showed better predictive performance compared with the GTV and PTV radiomics models, with the AUCs of 0.950 (95% CI 0.911-0.989), 0.844 (95% CI 0.728-0.959), and 0.815 (95% CI 0.713-0.917) in the training, internal validation and external validation sets, respectively. In the clinical model, tumor shape, lobulation sign and maximal diameter were the independent predictors of CC in invasive LUAD. The combined model including independent clinical predictors and GPTV-Radscore show the considerable instructive to clinical practice, with the AUCs of 0.954(95% CI 0.918-0.990), 0.861(95% CI 0.752-0.970), and 0.794(95% CI 0.690-0.898) in training, internal validation, and external validation sets, respectively. DCA showed that the combined model had good clinical value and correction effect. CONCLUSION: Radiomics model is a very powerful tool for predicting CC growth pattern in invasive LUAD and can help clinicians make the strategies of treatment and surveillance in patients with invasive LUAD.

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This article presents the first results for elemental composition of 193 fragments ceramic from four sites located in Ventarrón-Collud archaeological complex, Peru. The results from EDXRF and multivariate analysis indicated statistical similarity among four groups of ceramic fragments, selected by remarkable stylistic variation, collected from different archaeological space/time contexts. The correspondence in the elemental composition of the ceramic paste of the artifacts corroborates the hypothesis that similar raw materials were used consistently throughout the entire occupation of this archaeological complex.

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Systemic vasculitis is a group of rare diseases that share an essential characteristic: inflammation of blood vessel walls. This injury occurs during the disease course, but specific features vary for each entity. In this paper, we will address relevant aspects of the newest monogenic mutation vasculitis, such as deficiency of adenosine deaminase 2 (ADA2) and VEXAS syndrome (UBA1), and other relevant vasculitis, such as Cogan syndrome and Susac syndrome that may share some similarities with them.

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In biological systems, nanoparticles interact with biomolecules, which may undergo protein corona formation that can result in noncontrolled aggregation. Therefore, comprehending the behavior and evolution of nanoparticles in the presence of biological fluids is paramount in nanomedicine. However, traditional lab-based colloid methods characterize diluted suspensions in low-complexity media, which hinders in-depth studies in complex biological environments. Here, we apply X-ray photon correlation spectroscopy (XPCS) to investigate silica nanoparticles (SiO2) in various environments, ranging from low to high complex biological media. Interestingly, SiO2 revealed Brownian motion behavior, irrespective of the complexity of the chosen media. Moreover, the SiO2 surface and media composition were tailored to underline the differences between a corona-free system from protein corona and aggregates formation. Our results highlighted XPCS potential for real-time nanoparticle analysis in biological media, surpassing the limitations of conventional techniques and offering deeper insights into colloidal behavior in complex environments.

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Purine nucleotides and nucleosides play critical roles in various pathological conditions, including tumor cell growth. Adenosine triphosphate (ATP) activates pro-tumor receptors, while adenosine (ADO) is a potent immunosuppressant and modulator of cell growth. This study aims to analyze the purinergic actions of ATP and its metabolites, associated enzymes, and P1 or P2 class receptors in primary central nervous system tumors. Additionally, we sought to correlate the levels of nucleosides and the density of P1, P2X, and P2Y receptors in cells with tumor progression. The results indicate that purinergic signaling depends on the receptor concentration and signaling molecules specific to each cell type, tissue, and tumor histology. The purinergic system may function as either a tumor-promoting agent or an antitumor factor, depending on the microenvironmental conditions and the concentrations of receptors and their respective activators. Notably, ATP emerges as the most significant extracellular signal, capable of being converted into other cellular stimulators pertinent to neoplasms, such as adenosine diphosphate, adenosine monophosphate, adenosine, and inosine. Consequently, a cascade of responses to these stimuli promotes tumor development, cell division, and metastasis. Purine nucleotides in central nervous system tumors are pivotal in cellular responses in glioblastoma multiforme, vestibular schwannoma, medulloblastoma, adenomas, gliomas, meningiomas, and pineal tumors. These findings hold the potential for developing novel therapeutic strategies and aiding in therapeutic management.

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La radiografía de tórax sigue siendo fundamental para la evaluación de patologías torácicas en lactantes. Antes de iniciar su interpretación, muchos autores sugieren revisar la técnica radiológica, ya que a esta edad se presentan varias particularidades técnicas que deben tenerse en cuenta para evitar errores interpretativos y no confundir hallazgos técnicos con patologías. Entre estas particularidades técnicas se deben evaluar: el centraje transversal o rotación, el centraje longitudinal o posición lordótica, el grado de inspiración, la posición de la vía aérea superior, la penetración o exposición de la radiografía, tipos de proyecciones y el movimiento. El objetivo de esta revisión es comentar y ejemplificar las peculiaridades técnicas que presenta la radiografía de tórax en lactantes y que pueden llevar a interpretaciones erróneas.

The chest X-ray remains essential for evaluating thoracic pathology in infants. Before beginning its interpretation, many authors recommend assessing the radiographic technique, as several technical peculiarities must be considered at this age to avoid interpretive errors and prevent mistaking technical artifacts for pathology. The technical aspects to be evaluated include transverse centering or rotation, longitudinal centering or lordotic position, degree of inspiration, upper airway positioning, radiograph penetration or exposure, projection types, and movement. The objective of this review is to discuss and illustrate the technical peculiarities of infant chest X-rays that can lead to erroneous interpretations.

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BACKGROUND: Metabolic syndrome refers to the coexistence of several known cardiovascular risk factors, including insulin resistance, obesity, atherogenic dyslipidemia, and hypertension. These conditions are interrelated and share underlying mediators, mechanisms, and pathways. Improvement in dietary habits has been shown to improve metabolic parameters in patients undergoing treatment with different diets. METHODS: A systematic search in different databases was realized using the keywords "Metabolic syndrome", "X syndrome", "Dash dietary" and "Dash diet". Finally, six studies were included in this meta-analysis. RESULTS: All articles comparing the DASH diet vs. other diet modalities reported significant differences in favor of the DASH diet on Systolic blood pressure (SBP) (standardized mean difference [SMD] = -8.06, confidence interval [CI] = -9.89 to -7.32, and p < 0.00001), Diastolic blood pressure (SMD = -6.38, CI = -7.62 to -5.14, and p < 0.00001), Cholesterol HDL (SMD = 0.70, CI = 0.53 to 0.88, and p < 0.00001) and Cholesterol LDL (SMD = -1.29, CI = -1.73 to -0.85, and p < 0.00001) scales. CONCLUSIONS: The DASH diet has been shown to be beneficial in altered parameters in patients with MS, and the resulting improvements can significantly affect the daily health of these patients. We therefore recommend that professionals who manage these pathologies promote the use of the DASH diet for the management of specific symptoms.

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Aims: Aortic elongation can result from age-related changes, congenital factors, aneurysms, or conditions affecting blood vessel elasticity. It is associated with cardiovascular diseases and severe complications like aortic aneurysms and dissection. We assess qualitatively and quantitatively explainable methods to understand the decisions of a deep learning model for detecting aortic elongation using chest X-ray (CXR) images. Methods and results: In this study, we evaluated the performance of deep learning models (DenseNet and EfficientNet) for detecting aortic elongation using transfer learning and fine-tuning techniques with CXR images as input. EfficientNet achieved higher accuracy (86.7% ± 2.1), precision (82.7% ± 2.7), specificity (89.4% ± 1.7), F1 score (82.5% ± 2.9), and area under the receiver operating characteristic (92.7% ± 0.6) but lower sensitivity (82.3% ± 3.2) compared with DenseNet. To gain insights into the decision-making process of these models, we employed gradient-weighted class activation mapping and local interpretable model-agnostic explanations explainability methods, which enabled us to identify the expected location of aortic elongation in CXR images. Additionally, we used the pixel-flipping method to quantitatively assess the model interpretations, providing valuable insights into model behaviour. Conclusion: Our study presents a comprehensive strategy for analysing CXR images by integrating aortic elongation detection models with explainable artificial intelligence techniques. By enhancing the interpretability and understanding of the models' decisions, this approach holds promise for aiding clinicians in timely and accurate diagnosis, potentially improving patient outcomes in clinical practice.

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Purinergic signaling regulates many metabolic functions and is implicated in liver physiology and pathophysiology. Liver functionality is modulated by ionotropic P2X and metabotropic P2Y receptors, specifically P2Y1, P2Y2, and P2Y6 subtypes, which physiologically exert their influence through calcium signaling, a key second messenger controlling glucose and fat metabolism in hepatocytes. Purinergic receptors, acting through calcium signaling, play an important role in a range of liver diseases. Ionotropic P2X receptors, such as the P2X7 subtype, and certain metabotropic P2Y receptors can induce aberrant intracellular calcium transients that impact normal hepatocyte function and initiate the activation of other liver cell types, including Kupffer and stellate cells. These P2Y- and P2X-dependent intracellular calcium increases are particularly relevant in hepatic disease states, where stellate and Kupffer cells respond with innate immune reactions to challenges, such as excess fat accumulation, chronic alcohol abuse, or infections, and can eventually lead to liver fibrosis. This review explores the consequences of excessive extracellular ATP accumulation, triggering calcium influx through P2X4 and P2X7 receptors, inflammasome activation, and programmed cell death. In addition, P2Y2 receptors contribute to hepatic steatosis and insulin resistance, while inhibiting the expression of P2Y6 receptors can alleviate alcoholic liver steatosis. Adenosine receptors may also contribute to fibrosis through extracellular matrix production by fibroblasts. Thus, pharmacological modulation of P1 and P2 receptors and downstream calcium signaling may open novel therapeutic avenues.

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In this work, we cloned and functionally expressed two novel GABAA receptor subunits from Procambarus clarkii crayfish. These two new subunits, PcGABAA-α and PcGABAA-ß2, revealed significant sequence homology with the PcGABAA-ß subunit, previously identified in our laboratory. In addition, PcGABAA-α subunit also shared a significant degree of identity with the Drosophila melanogaster genes DmGRD (GABA and glycine-like receptor subunits of Drosophila) as well as PcGABAA-ß2 subunit with DmLCCH3 (ligand-gated chloride channel homolog 3). Electrophysiological recordings showed that the expression in HEK cells of the novel subunits, either alone or in combination, failed to form functional homo- or heteromeric receptors. However, the co-expression of PcGABAA-α with PcGABAA-ß evoked sodium- or chloride-dependent currents that accurately reproduced the time course of the GABA-evoked currents in the X-organ neurons from crayfish, suggesting that these GABA subunits combine to form two types of GABA receptors, one with cationic selectivity filter and the other preferentially permeates anions. On the other hand, PcGABAA-ß2 and PcGABAA-ß co-expression generated a chloride current that does not show desensitization. Muscimol reproduced the time course of GABA-evoked currents in all functional receptors, and picrotoxin blocked these currents; bicuculline did not block any of the recorded currents. Reverse transcription polymerae chain reaction (RT-PCR) amplifications and FISH revealed that PcGABAA-α and PcGABAA-ß2 are predominantly expressed in the crayfish nervous system. Altogether, these findings provide the first evidence of a neural GABA-gated cationic channel in the crayfish, increasing our understanding of the role of these new GABAA receptor subunits in native heteromeric receptors.

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Background: Adipose tissue excess is associated with adverse health outcomes, including type 2 diabetes. Body mass index (BMI) is used to evaluate obesity but is inaccurate as it does not account for muscle mass, bone density, and fat distribution. Accurate measurement of adipose tissue through dual-energy X-ray absorptiometry (DXA) and computed axial tomography (CT) is crucial for managing and monitoring adiposity-related diseases. Still, these are not easily accessible in most hospitals in Mexico. Bioelectrical impedance analysis (BIA) is non-invasive and low-cost but may not be reliable in conditions affecting the body's hydration status, like diabetes. Objectives: To assess fat mass concordance between BIA and DXA in Hispanic-American adults with type 2 diabetes mellitus (T2DM). Methods: Cross-sectional study of a non-probabilistic sample of subjects over 18 years with type 2 diabetes. We used DXA as the reference method. Results: We evaluated the accuracy of FM estimation through BIA and DXA in 309 subjects with type 2 diabetes. Results showed a trend of overestimating the diagnosis of obesity using BIA, especially in individuals with a higher fat mass index (FMI). At the group level, we found BIA accurate; however, at the individual level, it is not. The bias between the 2 methods showed a statistically significant overestimation of body fat by BIA (P ⩽ .01) in both sexes. BIA demonstrated high precision in estimating fat mass. We were able to provide a correction factor of 0.55 kg in men. Conclusion: BIA is inaccurate compared to DXA for body composition assessment in patients with diabetes. Inaccurate measurements can result in misclassification. However, BIA is precise for body composition assessment in patients with diabetes, so it is reliable for tracking patient progress over time.

Agreement between bioelectrical impedance analysis and dual-energy X-ray absorptiometry to estimate fat mass in adults with type 2 Diabetes Mellitus This study compares 2 methods for measuring body composition in patients with diabetes in Mexico. The first method is Bioelectrical Impedance Analysis (BIA), which is non-invasive, low-cost, and easy to use but may not be reliable in conditions that affect the body's hydration status, like diabetes. The second method is Dual-energy X-ray Absorptiometry (DXA), which is more accurate but less easily accessible. The study was a cross-sectional evaluation of 309 participants over 18 years with type 2 diabetes mellitus (T2DM) by HbA1C levels. The present study found BIA to be precise for body composition assessment but not accurate compared to DXA as the reference method. The study showed a trend of overestimating the diagnosis of obesity using BIA, especially in individuals with a higher fat mass index. This study found BIA is accurate at the group level but not at the individual level. The bias between the 2 methods showed a statistically significant overestimation of body fat by BIA. We provided a correction factor of 0.55 kg in men but not women. BIA is not ideal for diagnosing obesity but is reliable for tracking patient progress over time.

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PURPOSE: To analyze the microstructural and mechanical properties of various commercial trademarks of lithium disilicate ceramics for CAD-CAM systems. MATERIALS AND METHODS: Specimens of different lithium disilicate ceramics were obtained and randomized into 5 groups (n = 14): EM: e.max CAD; RT: Rosetta SM; EV: Evolith; PM: Smile-Lithium CAD; and, HS: HaHaSmile. The microstructural analysis was performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM); for flexural strength, the three-point bending flexure test was used. XRD and SEM data were qualitatively evaluated. Data from flexural strength were assessed with one-way ANOVA test (α = 0.05) and Weibull analysis. RESULTS: High peaks corresponding to the lithium metasilicate and lithium disilicate pattern with similar intensities were observed in all ceramics in the XRD analysis. SEM images showed similar patterns of crystalline structure in the EM and RT ceramics, while the other three groups presented different crystal morphologies than the previous ones and were similar to each other. No differences were found in flexural strength among the groups (p = 0.28). CONCLUSIONS: The CAD-CAM lithium disilicate ceramics showed comparable crystalline intensities. The microstructure of the EM and RT ceramics were different from the other groups. Flexural strength was similar among all ceramics.

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In this work, bismuth ferrites (BFO) nanoparticles were produced in the form of using sol-gel technique, followed by annealing in a tube furnace in temperatures from 400 °C to 650 ºC. X-ray diffraction (XRD) results showed the formation of small sizes nanoparticles (NPs) with high purity. Structural analysis displayed that annealing at 600 ºC could make BFO NPs be fitted to rhombohedral space group (R3c), with small quantity of spurious phases. The sizes of the BFO nanoparticles determined by transmission electron microscopy (HRTEM) are between 50 to 100 nm. To evaluate the efficiency of BFO in antimicrobial susceptibility tests, the nanoparticles were dispersed through nanoemulsion and tested agar diffusion method and dilution in a 96 well plate using a Gram positive strains (Staphylococcus aureus) and Gram negative strain (Escherichia coli). The antibacterial activity of the BFO NPs was partially tested at concentrations of 2 mg/mL with MIC greater than 60 µg/mL for both bacteria.

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BACKGROUND: Familial Partial Lipodystrophy (FPLD) is a disease with wide clinical and genetic variation, with seven different subtypes described. Until genetic testing becomes feasible in clinical practice, non-invasive tools are used to evaluate body composition in lipodystrophic patients. This study aimed to analyze the different anthropometric parameters used for screening and diagnosis of FPLD, such as thigh skinfold thickness (TS), Köb index (Köbi), leg fat percentage (LFP), fat mass ratio (FMR) and leg-to-total fat mass ratio in grams (LTR), by dual-energy X-ray absorptiometry, focusing on determining cutoff points for TS and LFP within a Brazilian population. METHODS: Thirty-seven patients with FPLD and seventy-four healthy controls matched for body mass index, sex and age were studied. Data were collected through medical record review after signing informed consent. All participants had body fat distribution evaluated by skinfolds and DXA measures. Fasting blood samples were collected to evaluate glycemic and lipid profiles. Genetic studies were carried out on all patients. Two groups were categorized based on genetic testing and/or anthropometric characteristics: FPLD+ (positive genetic test) and FPLD1 (negative genetic testing, but positive clinical/anthropometric criteria for FPLD). RESULTS: Eighteen (48.6%) patients were classified as FPLD+, and 19 (51.4%) as FPLD1. Unlike what is described in the literature, the LMNA variant in codon 582 was the most common. Among the main diagnostic parameters of FPLD, a statistical difference was observed between the groups for, Köbi, TS, LFP, FMR, and LTR. A cutoff point of 20 mm for TS in FPLD women was found, which is lower than the value classically described in the literature for the diagnosis of FPLD. Additionally, an LFP < 29.6% appears to be a useful tool to aid in the diagnosis of these women. CONCLUSION: Combining anthropometric measurements to assess body fat distribution can lead to a more accurate diagnosis of FPLD. This study suggests new cutoff points for thigh skinfold and leg fat percentage in women with suspected FPLD in Brazil. Further studies are needed to confirm these findings.

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Introduction: Severe COVID-19 can result in long-term sequelae known as "chronic COVID," characterized by a wide range of persistent physical and mental symptoms. Chest imaging and pulmonary function test alterations have been observed in recovered patients. Most studies focus on up to a 3-month follow-up after symptom onset or hospital discharge, with few reports on long-term follow-up and limited evidence regarding disease progression in Latin America. Methods: This study aims to describe the clinical characteristics and changes in pulmonary function, imaging, and quality of life in severe and critical COVID-19 patients requiring ICU admission in a high-complexity hospital in Latin America. A prospective cohort of survivors underwent clinical, radiological, pulmonary function, and quality of life assessments 6 and 12 months post-discharge. Results: One hundred twelve patients were included, all of whom attended the 6-month follow-up, and 99 returned for the 12-month follow-up. Most subjects had no previous respiratory symptoms or significant medical history. At the end of the follow-up period, 74% of the patients showed interstitial infiltrates in chest tomography and a higher frequency of fibroatelectatic tracts and parenchymal bands. Pulmonary function tests returned to normal ranges, except for carbon monoxide diffusion, but no altered scores were reported in the questionnaires. Conclusion: Despite residual radiological findings, most parameters studied in severe and critical COVID-19 survivors improved over the 12-month follow-up period. Regardless of the imaging abnormalities, the improvement in variables such as symptomatic relief and normal pulmonary function suggests that these alterations are transient. Carbon monoxide diffusion did not normalize by the end of the follow-up, which is consistent with the abnormalities reported in multiple studies, indicating a potential disease-related pattern.

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Plasma focus devices represent a class of hot and dense plasma sources that serve a dual role in fundamental plasma research and practical applications. These devices allow the observation of various phenomena, including the z-pinch effect, nuclear fusion reactions, plasma filaments, bursts, shocks, jets, X-rays, neutron pulses, ions, and electron beams. In recent years, considerable efforts have been directed toward miniaturizing plasma focus devices, driven by the pursuit of both basic studies and technological advancements. In this paper, we present the design and construction of a compact, portable pulsed plasma source based on plasma focus technology, operating at the ~2-4 Joule energy range for versatile applications (PF-2J: 120 nF capacitance, 6-9 kV charging voltage, 40 nH inductance, 2.16-4.86 J stored energy, and 10-15 kA maximum current at short circuit). The components of the device, including capacitors, spark gaps, discharge chambers, and power supplies, are transportable within hand luggage. The electrical characteristics of the discharge were thoroughly characterized using voltage and current derivative monitoring techniques. A peak current of 15 kiloamperes was achieved within 110 nanoseconds in a short-circuit configuration at a 9 kV charging voltage. Plasma dynamics were captured through optical refractive diagnostics employing a pulsed Nd-YAG laser with a 170-picosecond pulse duration. Clear evidence of the z-pinch effect was observed during discharges in a deuterium atmosphere at 4 millibars and 6 kilovolts. The measured pinch length and radius were approximately 0.8 mm and less than 100 µm, respectively. Additionally, we explore the potential applications of this compact pulsed plasma source. These include its use as a plasma shock irradiation device for analyzing materials intended for the first wall of nuclear fusion reactors, its capability in material film deposition, and its utility as an educational tool in experimental plasma physics. We also show its potential as a pulsed plasma thruster for nanosatellites, showcasing the advantages of miniaturized plasma focus technology.

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Exposure to the non-protein amino acid cyanotoxin ß-N-methylamino-L-alanine (BMAA), released by cyanobacteria found in many water reservoirs has been associated with neurodegenerative diseases. We previously demonstrated that BMAA induced cell death in both retina photoreceptors (PHRs) and amacrine neurons by triggering different molecular pathways, as activation of NMDA receptors and formation of carbamate-adducts was only observed in amacrine cell death. We established that activation of Retinoid X Receptors (RXR) protects retinal cells, including retina pigment epithelial (RPE) cells from oxidative stress-induced apoptosis. We now investigated the mechanisms underlying BMAA toxicity in these cells and those involved in RXR protection. BMAA addition to rat retinal neurons during early development in vitro increased reactive oxygen species (ROS) generation and polyADP ribose polymers (PAR) formation, while pre-treatment with serine (Ser) before BMAA addition decreased PHR death. Notably, RXR activation with the HX630 agonist prevented BMAA-induced death in both neuronal types, reducing ROS generation, preserving mitochondrial potential, and decreasing TUNEL-positive cells and PAR formation. This suggests that BMAA promoted PHR death by substituting Ser in polypeptide chains and by inducing polyADP ribose polymerase activation. BMAA induced cell death in ARPE-19 cells, a human epithelial cell line; RXR activation prevented this death, decreasing ROS generation and caspase 3/7 activity. These findings suggest that RXR activation prevents BMAA harmful effects on retinal neurons and RPE cells, supporting this activation as a broad-spectrum strategy for treating retina degenerations.

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