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Sugarcane is used to produce sugar, ethanol, and other by-products, so it is considered one of the most important crops worldwide. Using temporary immersion systems for sugarcane micropropagation represents an alternative to reduce the labor force, increase plant development, and improve plant quality. Temporary immersion systems are semi-automated bioreactors designed for the large-scale propagation of tissues, embryos, and organs. These are temporarily exposed in a liquid culture medium under a specific time and immersion frequency. Using this protocol and a temporary immersion bioreactor, it is possible to achieve multiplication and rooting. The use of temporary immersion bioreactors improves the multiplication rate and the rooting of sugarcane, reducing the culture time, labor force, and reagents needed while maintaining high survival rates during acclimatization.

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The use of curved layers in fused filament fabrication could lead to various advantages in surface finishing and mechanical properties. Here, the influence of three different structural and manufacturing parameters (volume fraction, raster arrangement, and the use of curved or planar layers) on the mechanical properties of lattice structures under three-point bending is studied. Two different raster arrangements were considered, i.e., those with rasters at planes parallel to the principal axes of the samples and those diagonally arranged, all at four different volume fractions. All different samples were additively manufactured using planar and curved layers. Samples were further dimensionally inspected to refine the computational models before their analysis via finite element simulations. The linear elastic region of the load-displacement curves was further analyzed numerically via finite element models. Predictions with finite element models resulted in good agreement with errors below 10%. Samples with diagonal rasters were 70% softer than those parallel to the principal axes.

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The use of agrochemicals has caused environmental problems and toxicity to humans, so natural alternatives for disease control during harvest and postharvest have been evaluated. The aim of this study was to evaluate cinnamon essential oil, neem oil, and black sapote fruit extract for in vitro inhibition of fungi isolated from chayote fruit. The extracts were applied at 300, 350, and 400 ppm in Petri dishes and the mycelial growth of Fusarium oxysporum, Fusarium solani, Goetrichum sp., and Phytophthora capsici was evaluated for 7 days, and the percentage of mycelial growth inhibition per day was calculated. Cinnamon oil showed a fungicidal effect at all concentrations. Neem oil at 400 ppm showed a 42.3% reduction in the growth of F. solani and 27.8% reduction in the growth of F. oxysporum, while at 350 ppm it inhibited the mycelial growth of Phytophthora capsici by 53.3% and of Goetrichum sp. by 20.9%; finally, the black sapote extract at 400 ppm inhibited 21.9-28.6% of the growth of all fungi. The growth of postharvest fungi on chayote fruit could be prevented or reduced by applying the plant extracts evaluated at adequate concentrations.

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The symbiotic associations between arbuscular mycorrhizal fungi (AMF) and plants can induce drought stress tolerance. In this study, we evaluated the effect of Glomus intraradices, a mycorrhizal fungus, on the ex vitro development and survival of sugarcane plantlets subjected to drought stress during the acclimatization stage of micropropagation. In vitro obtained sugarcane plantlets (Saccharum spp. cv Mex 69-290) were inoculated with different doses of G. intraradices (0, 100, and 200 spores per plantlet) during greenhouse acclimatization. Sixty days after inoculation, plantlets were temporarily subjected to drought stress. We evaluated the survival rate, total chlorophyll, total protein, carotenoids, proline, betaine glycine, soluble phenolic content, and antioxidant capacity every 3 days for 12 days. Symbiotic interaction was characterized by microscopy. Our results showed that the survival rate of inoculated plants was higher in 45% than the treatment without mycorrhizae. Total chlorophyll, protein, proline, betaine glycine content, and antioxidant capacity were increased in AMF inoculated plants. The soluble phenolic content was higher in non-inoculated plants than the treatment with mycorrhizae during the drought stress period. Microscopy showed the symbiotic relationship between plant and AMF. The early inoculation of 100 spores of G. intraradices per sugarcane plantlet during the acclimatization stage could represent a preconditioning advantage before transplanting into the field and establishing basic seedbeds.

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Neurodegenerative diseases pose significant challenges due to their impact on brain structure, function, and cognition. As life expectancy rises, the prevalence of these disorders is rapidly increasing, resulting in substantial personal, familial, and societal burdens. Efforts have been made to optimize the diagnostic and therapeutic processes, primarily focusing on clinical, cognitive, and imaging characterization. However, the emergence of non-invasive brain stimulation techniques, specifically transcranial magnetic stimulation (TMS), offers unique functional insights and diagnostic potential. TMS allows direct evaluation of brain function, providing valuable information inaccessible through other methods. This review aims to summarize the current and potential diagnostic utility of TMS in investigating neurodegenerative diseases, highlighting its relevance to the field of cognitive neuroscience. The findings presented herein contribute to the growing body of research focused on improving our understanding and management of these debilitating conditions, particularly in regions with limited resources and a pressing need for innovative approaches.

As doenças neurodegenerativas representam desafio significativo por seu impacto na estrutura cerebral, função e cognição. À medida que a expectativa de vida aumenta, a prevalência dessas doenças cresce rapidamente, resultando em substanciais encargos pessoais, familiares e sociais. Esforços têm sido feitos para otimizar os processos diagnósticos e terapêuticos, com foco principal na caracterização clínica, cognitiva e de imagem. No entanto, o surgimento de técnicas de estimulação cerebral não invasivas, especificamente a estimulação magnética transcraniana (EMT), oferece compreensão funcional e potencial diagnóstico únicos. A TMS permite a avaliação direta da função cerebral, fornecendo informações valiosas inacessíveis por outros métodos. Esta revisão teve como objetivo resumir a utilidade diagnóstica atual e potencial da EMT na investigação de doenças neurodegenerativas, destacando sua relevância para o campo da neurociência cognitiva. As conclusões aqui apresentadas contribuem para o crescente corpo de investigação centrado na melhoria da nossa compreensão e gestão dessas condições debilitantes, particularmente em regiões com recursos limitados e necessidade premente de abordagens inovadoras.

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ABSTRACT. Neurodegenerative diseases pose significant challenges due to their impact on brain structure, function, and cognition. As life expectancy rises, the prevalence of these disorders is rapidly increasing, resulting in substantial personal, familial, and societal burdens. Efforts have been made to optimize the diagnostic and therapeutic processes, primarily focusing on clinical, cognitive, and imaging characterization. However, the emergence of non-invasive brain stimulation techniques, specifically transcranial magnetic stimulation (TMS), offers unique functional insights and diagnostic potential. TMS allows direct evaluation of brain function, providing valuable information inaccessible through other methods. This review aims to summarize the current and potential diagnostic utility of TMS in investigating neurodegenerative diseases, highlighting its relevance to the field of cognitive neuroscience. The findings presented herein contribute to the growing body of research focused on improving our understanding and management of these debilitating conditions, particularly in regions with limited resources and a pressing need for innovative approaches.

RESUMO. As doenças neurodegenerativas representam desafio significativo por seu impacto na estrutura cerebral, função e cognição. À medida que a expectativa de vida aumenta, a prevalência dessas doenças cresce rapidamente, resultando em substanciais encargos pessoais, familiares e sociais. Esforços têm sido feitos para otimizar os processos diagnósticos e terapêuticos, com foco principal na caracterização clínica, cognitiva e de imagem. No entanto, o surgimento de técnicas de estimulação cerebral não invasivas, especificamente a estimulação magnética transcraniana (EMT), oferece compreensão funcional e potencial diagnóstico únicos. A TMS permite a avaliação direta da função cerebral, fornecendo informações valiosas inacessíveis por outros métodos. Esta revisão teve como objetivo resumir a utilidade diagnóstica atual e potencial da EMT na investigação de doenças neurodegenerativas, destacando sua relevância para o campo da neurociência cognitiva. As conclusões aqui apresentadas contribuem para o crescente corpo de investigação centrado na melhoria da nossa compreensão e gestão dessas condições debilitantes, particularmente em regiões com recursos limitados e necessidade premente de abordagens inovadoras.

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Somatic embryogenesis (SE) serves as a key biological model for studying cell totipotency and the ontogenic processes of zygotic embryogenesis in plants. The SE process, under in vitro conditions, can be induced from different sources of explant cultivated in a culture medium with plant growth regulators (PGR) or by subjecting tissues to abiotic stress treatments. Somatic embryogenesis, in plant tissue culture (PTC), is a multifactorial event. The use of PGR, particularly auxins, is an important factor during induction. However, in vitro abiotic stress treatments are physiologically, biochemically, and genetically relevant and should be further studied.

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Soil salinity is a problem that affects soil fertility and threatens agri-food crop production worldwide. Biotechnology, through plant micropropagation and the use of biofertilizers such as arbuscular mycorrhizal fungi (AMF), is an alternative to increase productivity and induce tolerance to salinity stress in different crops. This study aimed to evaluate the effect of different doses of the fungus Glomus intraradices on the ex vitro development of taro (Colocasia esculenta L. Schott cv. Criolla) plantlets under salinity stress during the acclimatization stage. In vitro-obtained C. esculenta plantlets were inoculated at different doses (0, 100, and 200 spores per plantlet) of G. intraradices during acclimatization. At 60 d of acclimatization in the greenhouse, plantlets were exposed to 100 mM NaCl salinity stress for 10 d. After the stress period, plantlet development, colonization percentage, and biomass were evaluated. In addition, the content of chlorophyll, carotenoids, proteins, proline, glycine-betaine, soluble phenols, and antioxidant capacity were quantified. The results showed differences in the developmental, physiological, and biochemical variables evaluated; however, no changes in total protein content were observed. Spore colonization showed that the symbiotic association has positive effects on the development of plantlets with or without salinity stress. This symbiotic interaction contributes to salinity stress tolerance in C. esculenta plantlets. The early application of AMF in in vitro-obtained taro plantlets is an alternative to increase or maintain the productivity of this crop in saline soils.

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Description and morphological analysis of copepods inhabiting a water body with high arsenic concentrations (32.79 to 62.29 mg L-1) were performed to identify some effect on the development of individuals due to the arsenic concentrations. Detailed morphology of prosomal and urosomal appendages along the development of the specimens was considered. The results showed that the freshwater copepod Paracyclops novenarius Reid, 1987 inhabits this water body, and previously, it was recorded as Paracyclops chiltoni (Thomson GM, 1882) on this site. Moreover, this becomes the first record of P. novenarius in Mexico. Morphological analysis showed a normal and stable development along the different instars, different arsenic concentrations in the media, and different sampled dates between the analyzed specimens, suggesting that the high arsenic concentrations do not affect the morphology of P. novenarius, including all its development and adult instars, which differs from other copepods and other groups such as Cladocera and Rotifera, where morphological changes due to metals and metalloids have been observed but in low concentrations of these elements. The results of this study contribute to the existing reports of the genus Paracyclops (Claus 1893) in Mexico and could provide information for environmental impact assessments on aquatic systems.

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Drought-induced water stress affects the productivity of the Vanilla planifolia Jacks. ex Andrews crop. In vitro culture technique is an effective tool for the study of water stress tolerance mechanisms. This study aimed to evaluate the morphological, physiological and biochemical response of V. planifolia under in vitro water stress conditions induced with polyethylene glycol (PEG). In vitro regenerated shoots of 2 cm in length were subjected to different concentrations of PEG 6000 (0, 1, 2 and 3% w/v) using Murashige and Skoog semi-solid culture medium. At 60 days of culture, different growth variables, dry matter (DM) content, chlorophyll (Chl), soluble proteins (SP), proline (Pro), glycine betaine (GB), stomatal index (SI) and open stomata (%) were evaluated. Results showed a reduction in growth, Chl content, SP, SI and open stomata (%) with increasing PEG concentration, whereas DM, Pro and GB contents rose with increasing PEG concentration. In conclusion, PEG-induced osmotic stress allowed describing physiological and biochemical mechanisms of response to water stress. Furthermore, the determination of compatible Pro and GB osmolytes can be used as biochemical markers in future breeding programs for the early selection of water stress tolerant genotypes.

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Relapsing polychondritis (RP) is a rare multisystemic autoimmune disorder characterized by the inflammation and destruction of cartilages, with preference for auricular, nasal and laryngotracheal cartilages. RP may also affect proteoglycan-rich structures, such as, blood vessels, eyes, kidneys, and heart. The central nervous system (CNS) is involved in less than 3% of patients. We report a 32-year-old female with RP associated with a progressive subacute encephalopathy characterized by behavioral disturbances, auditory and visual hallucinations. The EEG showed generalized slow activity and a mononuclear pleocytosis with increased protein was found in the cerebrospinal fluid. The brain magnetic resonance imaging showed multiple supra and infratentorial nodular inflammatory lesions. After initiating treatment with corticosteroids and cyclophosphamide, a significant improvement in chondritis and neurological status was observed.

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Carbon nanotubes play an important role in plant biotechnology due to their effects on the growth and differentiation of cells, tissues, organs, and whole plants. This study aimed to evaluate the effect of multi-walled carbon nanotubes (MWCNTs) during in vitro multiplication of sugarcane (Saccharum spp.) using a temporary immersion system. Morphological characterization of MWCNTs was carried out under a transmission electron microscope. Different concentrations (0, 50, 100, 200 mg L-1) of MWCNTs were added to Murashige and Skoog liquid culture medium in the multiplication stage. At 30 d of culture, number of shoots per explant, shoot length, number of leaves per shoot, total chlorophyll, dry matter percentage, carbon percentage, and macro- and micronutrient content were evaluated. Results showed an increase in the development of sugarcane shoots at concentrations of 100 and 200 mg L-1 MWCNT. Total chlorophyll content increased at concentrations of 50 and 100 mg L-1 MWCNT, whereas macro- and micronutrient content was variable at the different MWCNT concentrations. Results suggest a hormetic effect, characterized by stimulation at low concentrations. In conclusion, the use of low concentrations of MWCNTs had positive effects on development, total chlorophyll, carbon percentage, and macro- and micronutrient (N, Ca, S, Fe, Cu, Zn and Na) contents during in vitro multiplication of sugarcane and may have a potential use in other species of agricultural interest.

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Subarachnoid hemorrhage (SAH) is a devastating disease, with a mortality rate of 35%. Among patients who survive the initial bleeding, the leading cause of morbidity and mortality is delayed cerebral ischemia (DCI). Electroencephalography (EEG) can detect cerebral ischemia in the early stages. We report a 66-year-old female patient who consulted for ictal headache and impaired consciousness. On admission, she was confused, dysarthric, and with meningeal signs. Brain angio-CT showed SAH FISHER IV and an aneurysm of the left posterior cerebral artery. After excluding the aneurysm (by coiling), the patient recovered the altered consciousness. Continuous EEG monitoring was initiated. On the sixth day of follow up, she had a transient headache and apathy. The brain MRI showed low cerebral blood flow in the left frontotemporal area, without ischemic lesions. On the seventh day, she presented expression aphasia and right facial-brachial paresis. Angiography confirmed severe vasospasm in M1 and M2 segments bilaterally. Pharmacological angioplasty with nimodipine was performed, with an excellent radiological response, although not clinical. A second MRI was carried out on the eighth day, which showed a left insular infarction and generalized vasospasm. A second therapeutic angiography was performed; the patient persisted with aphasia and left central facial paresis. The quantitative EEG analysis performed retrospectively showed a generalized reduction in the spectral edge frequency 95 (SEF95; meaning slowing in the EEG signal) at the fourth day of follow up, three days earlier than the clinical and imaging diagnosis of DCI was established.

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Relapsing polychondritis (RP) is a rare multisystemic autoimmune disorder characterized by the inflammation and destruction of cartilages, with preference for auricular, nasal and laryngotracheal cartilages. RP may also affect proteoglycan-rich structures, such as, blood vessels, eyes, kidneys, and heart. The central nervous system (CNS) is involved in less than 3% of patients. We report a 32-year-old female with RP associated with a progressive subacute encephalopathy characterized by behavioral disturbances, auditory and visual hallucinations. The EEG showed generalized slow activity and a mononuclear pleocytosis with increased protein was found in the cerebrospinal fluid. The brain magnetic resonance imaging showed multiple supra and infratentorial nodular inflammatory lesions. After initiating treatment with corticosteroids and cyclophosphamide, a significant improvement in chondritis and neurological status was observed.

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Subarachnoid hemorrhage (SAH) is a devastating disease, with a mortality rate of 35%. Among patients who survive the initial bleeding, the leading cause of morbidity and mortality is delayed cerebral ischemia (DCI). Electroencephalography (EEG) can detect cerebral ischemia in the early stages. We report a 66-year-old female patient who consulted for ictal headache and impaired consciousness. On admission, she was confused, dysarthric, and with meningeal signs. Brain angio-CT showed SAH FISHER IV and an aneurysm of the left posterior cerebral artery. After excluding the aneurysm (by coiling), the patient recovered the altered consciousness. Continuous EEG monitoring was initiated. On the sixth day of follow up, she had a transient headache and apathy. The brain MRI showed low cerebral blood flow in the left frontotemporal area, without ischemic lesions. On the seventh day, she presented expression aphasia and right facial-brachial paresis. Angiography confirmed severe vasospasm in M1 and M2 segments bilaterally. Pharmacological angioplasty with nimodipine was performed, with an excellent radiological response, although not clinical. A second MRI was carried out on the eighth day, which showed a left insular infarction and generalized vasospasm. A second therapeutic angiography was performed; the patient persisted with aphasia and left central facial paresis. The quantitative EEG analysis performed retrospectively showed a generalized reduction in the spectral edge frequency 95 (SEF95; meaning slowing in the EEG signal) at the fourth day of follow up, three days earlier than the clinical and imaging diagnosis of DCI was established.

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Worldwide demands of Vanilla planifolia lead to finding new options to produce large-scale and contaminant-free crops. Particularly, the Mexican Government has classified Vanilla planifolia at risk and it subject to protection programs since wild species are in danger of extinction and no more than 30 clones have been found. Nanotechnology could help to solve both demands and genetic variability, but toxicological concerns must be solved. In this work, we present the first study of the cytotoxic and genotoxic effects promoted by AgNPs in Vanilla planifolia plantlets after a very long exposure time of six weeks. Our results show that Vanilla planifolia plantlets growth with doses of 25 and 50 mg/L is favored with a small decrease in the mitotic index. A dose-dependency in the frequency of cells with chromosomal aberrations and micronuclei was found. However, genotoxic effects could be considered as minimum due to with the highest concentration employed (200 mg/L), the total percentage of chromatic aberrations is lower than 5% with only three micronuclei in 3000 cells, despite the long-time exposure to AgNP. Therefore, 25 and 50 mg/L (1.5 and 3 mg/L of metallic silver) were identified as safe concentrations for Vanilla planifolia growth on in vitro conditions. Exposure of plantlets to AgNPs increase the polymorphism registered by inter-simple sequence repeat method (ISSR), which could be useful to promote the genetic variability of this species.

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Introducción: La disfagia y sus complicaciones son una consulta frecuente en nuestra práctica clínica. En nuestro medio y en la literatura, el trago de bario ha sido tradicionalmente considerado el patrón de oro en la evaluación de los trastornos de la deglución; sin embargo, hemos observado que existen casos donde la sintomatología del paciente no concuerda con los resultados reportados en el examen. Revisando la literatura no encontramos un estudio comparativo entre la evaluación endoscópica y radiológica de la disfagia que soporte la necesidad de realizar ambas pruebas de forma no exclusiva. Objetivo: Determinar el nivel de acuerdo entre los hallazgos en la Evaluación Euncional Endoscópica de la Deglución (EFED) y la Cinedeglución con Esofagograma (CE) en pacientes con disfagia. Diseño: Estudio de evaluación de la concordancia. Materiales y Métodos: Estudio de evaluación de la concordancia con 47 pacientes, donde por medio de la revisión de historias clínicas se analizó la presencia o no de vertimiento, residuo faríngeo, penetración o aspiración en los reportes de CE y EFED, así como las características de la población estudiada. Resultados: El nivel de acuerdo (coeficiente de kappa) para residuo faríngeo fue de 0,123 (IC 95% -0.075; 0.321), para el hallazgo de penetración fue de 0,382 (IC 95% 0.158; 0.605) y para aspiración fue de 0,356 (IC 95% 0.086; 0.626). Para vertimiento no pudo ser calculado. Conclusiones: Reconociendo las limitaciones del estudio y conociendo las ventajas y desventajas de estos exámenes, consideramos que el no acuerdo justifica la realización de ambos exámenes porque según lo observado no hay un nivel de concordancia suficiente para realizar uno solo como método diagnóstico en algunos pacientes.

Background: Dysphagia and its complications are a frequent chief complaint in our clinical practice. Barium Swallow Pharyngoesophagography (BSP) has been traditionally considered the gold standard for the diagnosis of swallowing disorders. However, we have observed that in some cases the symptoms referred by the patient do not match the results reported by this test. As far as we know, there is no study that compares the endoscopic and radiological evaluation of swallowing disorders, in order to explain the importance of performing both tests in a non-exclusive way. Objectives: To determine the level of agreement between the findings in Fiberoptic endoscopic evaluation of swallowing (FEES) and BSP when evaluating patients with dysphagia. Methods: Agreement evaluation study, of medical records form 47 patients. An analysis of the reports for BSP and FEES was made, evaluating the presence or not of premature spillage, pharyngeal residue, penetration and aspiration. The characteristics of the population studied were also analyzed. Results: The level of agreement (kappa's coefficient) for pharyngeal residue was 0.123 (CI 95% -0.075; 0.321), for penetration was 0.382 (CI 95% 0.158; 0.605) and for aspiration was 0.356 (CI 95% 0.086; 0.626). The value for premature spillage could not be calculated. Conclusion: Recognizing the limitations of the study and acknowledging the advantages and disadvantages of both exams, we believe the non-agreement supports the fact of performing both exams, because according to the results, there is not enough concordance between the findings on FEES and the BSP in order to perform only one of them in some patients.

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RESUMEN La hidrólisis química o enzimática del bagazo de caña de azúcar permite la obtención de azúcares fermentables, utilizados en la producción biotecnológica de etanol, mediante el empleo de levaduras comerciales o autóctonas obtenidas de diferentes materiales lignocelulósicos. El objetivo de este trabajo fue valorar la capacidad de producción de e tanol de cepas de levaduras nativas, aisladas en medio YPD e hidrolizado de bagazo de caña de azúcar, concentrado hasta un 75 %. Utilizando como variables de estudio el tipo de cepa y el tiempo de proceso, se realizó un análisis multifactorial (ANOVA) para su evaluación. Los resultados obtenidos con la cepa seleccionada UAT-3, fueron para Yp/s de 0.441 7 g/g y QP de 0.076 7 g/L-h a las 120 h. Las condiciones de proceso utilizadas en el presente estudio permitieron aislar y seleccionar cepas nativas de Sacharomyces cereviseae, con características adecuadas para ser utilizadas en procesos biotecnológicos industriales de producción de etanol, utilizando como sustrato residuos o subproductos derivados de la in dustria azucarera como el bagazo de caña de azúcar.

ABSTRACT The chemical or enzymatic hydrolysis of sugar cane bagasse, allows the obtaining of fermentable sugars used in the biotechnological production of ethanol by using commercial or native yeasts obtained from different lignocellulosic materials. The purpose of this study was to assess the production capacity of ethanol from a native yeast strain isolated in YPD and hydrolyzed sugar cane bagasse concentrated up to 75 %. Using as study variables the type of strain and processing time, a multivariate analysis (ANOVA) was performed for its evaluation. The results achieved with the selected strain UAT-3, were 0.441 7 g/g for Yp/s and 0.076 7 g/L-h to 120 h for QP. The process conditions used in the present study allowed to isolate and select native strains of Sacharomyces cereviseae, with characteristics suitable to be used in industrial biotechnological proceses of ethanol production, using as substrate residues or by-products derived from the sugar industry such as bagasse of sugar.