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This review summarizes recent progress in our current understanding of the mechanisms underlying the cell death pathways in bryophytes, focusing on conserved pathways and particularities in comparison to angiosperms. Regulated cell death (RCD) plays key roles during essential processes along the plant life cycle. It is part of specific developmental programmes and maintains homeostasis of the organism in response to unfavourable environments. Bryophytes could provide valuable models to study developmental RCD processes as well as those triggered by biotic and abiotic stresses. Some pathways analogous to those present in angiosperms occur in the gametophytic haploid generation of bryophytes, allowing direct genetic studies. In this review, we focus on such RCD programmes, identifying core conserved mechanisms and raising new key questions to analyse RCD from an evolutionary perspective.

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In the current context of global warming, high temperature events are becoming more frequent and intense in many places around the world. In this context, understanding how plants sense and respond to heat is essential to develop new tools to prevent plant damage and address global food security, as high temperature events are threatening agricultural sustainability. This review summarizes and integrates our current understanding underlying the cellular, physiological, biochemical and molecular regulatory pathways triggered in plants under moderately high and extremely high temperature conditions. Given that extremely high temperatures can also trigger ferroptosis, the study of this cell death mechanism constitutes a strategic approach to understand how plants might overcome otherwise lethal temperature events.

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Background: We analyzed the seroepidemiology of Toxoplasma gondii infection in women of reproductive age in Chiapas, Mexico. Materials and Methods: One hundred seven women (mean age 25.3 years; range: 13-42 years) were enrolled in a public hospital. The presence of immunoglobulin G (IgG) antibodies to T. gondii in serum samples of participants was determined by an enzyme immunoassay. Bivariate and logistic regression analyses were used to determine the association between characteristics of women and seropositivity to T. gondii. Results: Of the 107 women surveyed, 49 (45.8%) were positive for anti-T. gondii IgG antibodies. T. gondii infection was positively associated with cats at home (odds ratio [OR] = 3.85; 95% confidence interval [CI]: 1.21-12.20; p = 0.02), and negatively associated with eating out of home (OR = 0.29; 95% CI: 0.11-0.80; p = 0.01). Conclusions: This is the highest T. gondii exposure rate in women of reproductive age reported in Mexico.

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This article describes the development, methodology, enrollment, and outcomes of a graduate technical elective course on synthetic cells and organelles offered at the University of New Mexico, a minority-majority institution, in Fall 2022. The course had a significant ethics component and took advantage of readily available, low cost, and no-cost teaching materials that are available online. The course was effective in attracting a diverse enrollment of graduate students and senior undergraduates, some of whom participated in a survey of their backgrounds and motivations after the course was over. The article also provides results from this survey. Courses such as the one described have the potential to increase access and participation in emerging fields of research and technology such as synthetic cells.

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Prognostic scales may help to optimize the use of hospital resources, which may be of prime interest in the context of a fast spreading pandemics. Nonetheless, such tools are underdeveloped in the context of COVID-19. In the present article we asked whether accurate prognostic scales could be developed to optimize the use of hospital resources. We retrospectively studied 467 files of hospitalized patients after COVID-19. The odds ratios for 16 different biomarkers were calculated, those that were significantly associated were screened by a Pearson's correlation, and such index was used to establish the mathematical function for each marker. The scales to predict the need for hospitalization, intensive-care requirement and mortality had enhanced sensitivities (0.91 CI 0.87-0.94; 0.96 CI 0.94-0.98; 0.96 CI 0.94-0.98; all with p < 0.0001) and specificities (0.74 CI 0.62-0.83; 0.92 CI 0.87-0.96 and 0.91 CI 0.86-0.94; all with p < 0.0001). Interestingly, when a different population was assayed, these parameters did not change considerably. These results show a novel approach to establish the mathematical function of a marker in the development of highly sensitive prognostic tools, which in this case, may aid in the optimization of hospital resources. An online version of the three algorithms can be found at: http://benepachuca.no-ip.org/covid/index.php.

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Research on abstract concepts (AC) suggests that while some AC are enacted indirectly and occasionally, others are largely grounded in our sensory-motor and affective experience, and the opportunities to enact them are countless, which would allow us to acquire them without supervision. From this, the following question arises: do embodiment and repeated exposure suffice to dispense with supervision in abstract concepts acquisition (ACA)? In the present study, this question was addressed in the context of tonal music cognition, which demands a high level of abstraction, and via musical materials that participants had frequently heard and sung. Specifically, highly trained, moderately trained, and untrained participants (24 each) were given 12 well-known melodic fragments ending on tones instantiating 6 different scale degrees (2 times each) and asked to group (round 1) or pair (round 2) those fragments whose last tone conveyed the same (or a similar enough) level of stability or rest. If embodiment and repeated exposure suffice for ACA, then one would expect a scale degree-based grouping strategy regardless of participants' training level. Results showed that only highly trained participants systematically grouped stimuli ending on the same scale degree, particularly in round 2; moderately trained participants' performance was mixed, and tonality's influence on untrained participants was negligible. Further, moderately trained and untrained participants performed inconsistently, discarding in round 2 almost all of the pairs formed in round 1. These findings are integrated with previous findings on the effect of language, affect, and category type on conceptualization to account for why and when ACA requires supervision.

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Regulated cell death (RCD) is an essential process that plays key roles along the plant life cycle. Unlike accidental cell death, which is an uncontrolled biological process, RCD involves integrated signaling cascades and precise molecular-mediated mechanisms that are triggered in response to specific exogenous or endogenous stimuli. Ferroptosis is a cell death pathway characterized by the iron-dependent accumulation of lipid reactive oxygen species. Although first described in animals, ferroptosis in plants shares all the main core mechanisms observed for ferroptosis in other systems. In plants as in animals, oxidant and antioxidant systems outline the process of lipid peroxidation during ferroptosis. In plants, cellular compartments such as mitochondria, chloroplasts and cytosol act cooperatively and coordinately to respond to changing redox environments. This particular context makes plants a unique model to study redox status regulation and cell death. In this review, we focus on our most recent understanding of the regulation of redox state and lipid peroxidation in plants and their role during ferroptosis.

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Introduction: The reasons for tooth loss have been well defined for several centuries. However, systematic analysis of the causes of tooth loss in the first years of the present century would shed light on the current manifestation of this phenomenon. Objective: Determine the main causes of tooth mortality in the last 20 years. Methods: A systematic review was conducted using the Boolean search engines in PubMed, Web of Science, Scopus and SciELO bibliographic search platforms. The search was based on the following MeSH terms: cause, motive, mortality, extraction, dental extraction, loss, and combinations thereof. The articles included were in English or Spanish. Calibration was performed by the authors to evaluate the articles to be selected. Results: A total 593 articles were retrieved: 16 from Web of Science, 39 from Scopus, 531 from Pubmed and 1 from SciELO, of which 26 were included in the study. A predominance was found of articles published in English (80.8 percent). The main causes of tooth mortality dealt with were dental caries (92.30 percent) and periodontal disease (50.0 percent). Conclusions: The evidence obtained in the last 20 years is insufficient to determine the main reasons for dental extraction by continent. There is little availability of articles about areas from the most densely populated and developed countries in each continent. The articles included showed a predominance of dental caries and periodontal disease as the main reasons for dental extraction(AU)

Introducción: Las razones de la pérdida dentaria han sido bien definidas desde hace varios siglos. Sin embargo, sistematizar sobre las causas en los primeros años del presente siglo aportaría una visión de cómo se manifiestan en la actualidad. Objetivo: Determinar las principales causas de mortalidad dental en los últimos 20 años. Métodos: Se realizó una revisión sistemática utilizando los motores de búsqueda booleanos en la plataforma de búsqueda bibliográfica de PubMed, Web of Science, Scopus y SciELO. Las palabras clave utilizadas para la búsqueda fueron MesH: causa, motivo, mortalidad, extracción, extracción dental, pérdida y una combinación entre ellas. Se incluyeron artículos en español e inglés. Se realizó una calibración entre los autores para la evaluación de los artículos a seleccionar. Resultados: Como resultado de la búsqueda se obtuvieron 593 artículos, de los cuales 16 fueron de Web of Science, 39 de Scopus, 531 de Pubmed y 1 de SciELO. Los artículos incluidos en el estudio fueron 26. Predominaron las investigaciones publicadas en inglés (80,8 por ciento), que destacó entre los motivos de mortalidad dental estudiados, se encontró un predominio de caries dental (92,30 por ciento) y enfermedad periodontal (50,0 por ciento). Conclusiones: La evidencia obtenida en los últimos 20 años para determinar las principales razones de extracción dentaria por continentes es insuficiente y se observa la poca presencia de artículos en poblaciones de países con mayor desarrollado y número de habitantes de cada continente. Los artículos incluidos mostraron un predominio de la caries dental y la enfermedad periodontal como los principales motivos de extracción dentaria(AU)

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This work presents a methodology for optimal compensation of reactive power in Electric Microgrids using a multicriteria decision algorithm based on heuristic methods. It was verified the optimal location and dimensioning of fixed capacitor banks in a microgrid with 14 buses with objective functions based on cost, efficiency and quality criteria in a maximum demand operating condition and also considering the constraints of objective variables in minimum demand scenarios. The proposed capacitance to be installed was considered as a discrete variable. The location of discretized reactive capacitances was simulated at candidate nodes analyzing the power flow in the case study, resulting in a wide solution space that was tackled by means of multicriteria optimization, using dominance elimination techniques and the weighted sum method for decision making. The variables analyzed were: cost, maximum and average deviations of the voltage profile, power factor, total losses in the lines of the system and THD. All these variables were also verified in minimum demand scenarios. The proposed solution provides significant improvements in the variables analyzed and verifies the optimal performance of the technique. The mathematical analysis demonstrates the need of addressing the reactive compensation problem by means of multicriteria decision and the proposal provides a very novel tool for calculating the location and dimensioning of reactive compensation devices in distribution systems and microgrids. The programming was done in the Matlab environment with simulations using Simulink. The case study analyzed is a very novel validated Microgrid system of which it is known the variables that take part of this analysis, as an approximation of the study of a very real Microgrid.

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Regulated cell death plays key roles during essential processes throughout the plant life cycle. It takes part in specific developmental programs and maintains homeostasis of the organism in response to unfavorable environments. Ferroptosis is a recently discovered iron-dependent cell death pathway characterized by the accumulation of lipid reactive oxygen species. In plants, ferroptosis shares all the main hallmarks described in other systems. Those specific features include biochemical and morphological signatures that seem to be conserved among species. However, plant cells have specific metabolic pathways and a high degree of metabolic compartmentalization. Together with their particular morphology, these features add more complexity to the plant ferroptosis pathway. In this review, we summarize the most recent advances in elucidating the roles of ferroptosis in plants, focusing on specific triggers, the main players, and underlying pathways.

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Sensing and response to high temperatures are crucial to prevent heat-related damage and to preserve cellular and metabolic functions. The response to heat stress is a complex and coordinated process that involves several subcellular compartments and multi-level regulatory networks that are synchronized to avoid cell damage while maintaining cellular homeostasis. In this review, we provide an insight into the most recent advances in elucidating the molecular mechanisms involved in heat stress sensing and response in Marchantia polymorpha. Based on the signaling pathways and genes that were identified in Marchantia, our analyses indicate that although with specific particularities, the core components of the heat stress response seem conserved in bryophytes and angiosperms. Liverworts not only constitute a powerful tool to study heat stress response and signaling pathways during plant evolution, but also provide key and simple mechanisms to cope with extreme temperatures. Given the increasing prevalence of high temperatures around the world as a result of global warming, this knowledge provides a new set of molecular tools with potential agronomical applications.

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The transient histaminergic system is among the first neurotransmitter systems to appear during brain development in the rat mesencephalon/rhombencephalon. Histamine increases FOXP2-positive deep-layer neuron differentiation of cortical neural stem cells through H1 receptor activation in vitro. The in utero or systemic administration of chlorpheniramine (H1 receptor antagonist/inverse agonist) during deep-layer cortical neurogenesis decreases FOXP2 neurons in the developing cortex, and H1R- or histidine decarboxylase-knockout mice show impairment in learning and memory, wakefulness and nociception, functions modulated by the cerebral cortex. Due to the role of H1R in cortical neural stem cell neurogenesis, the purpose of this study was to evaluate the postnatal impact of the systemic administration of chlorpheniramine during deep-layer cortical neuron differentiation (E12-14) in the primary motor cortex (M1) of neonates (P0) and 21-day-old pups (P21). Chlorpheniramine or vehicle were systemically administered (5 mg/kg, i.p.) to pregnant Wistar rats at gestational days 12-14, and the expression and distribution of deep- (FOXP2 and TBR1) and superficial-layer (SATB2) neuronal cortical markers were analyzed in neonates from both groups. The qRT-PCR analysis revealed a reduction in the expression of Satb2 and FoxP2. However, Western blot and immunofluorescence showed increased protein levels in the chlorpheniramine-treated group. In P21 pups, the three markers showed impaired distribution and increased immunofluorescence in the experimental group. The Sholl analysis evidenced altered dendritic arborization of deep-layer neurons, with lower excitability in response to histamine, as evaluated by whole-cell patch-clamp recording, as well as diminished depolarization-evoked [3H]-glutamate release from striatal slices. Overall, these results suggest long-lasting effects of blocking H1Rs during early neurogenesis that may impact the pathways involved in voluntary motor activity and cognition.

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In flowering plants, pollen tubes undergo a journey that starts in the stigma and ends in the ovule with the delivery of the sperm cells to achieve double fertilization. The pollen cell wall plays an essential role to accomplish all the steps required for the successful delivery of the male gametes. This extended path involves female tissue recognition, rapid hydration and germination, polar growth, and a tight regulation of cell wall synthesis and modification, as its properties change not only along the pollen tube but also in response to guidance cues inside the pistil. In this review, we focus on the most recent advances in elucidating the molecular mechanisms involved in the regulation of cell wall synthesis and modification during pollen germination, pollen tube growth, and rupture.

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Maternal diabetes has been related to low verbal task scores, impaired fine and gross motor skills, and poor performance in graphic and visuospatial tasks during childhood. The primary motor cortex is important for controlling motor functions, and embryos exposed to high glucose show changes in cell proliferation, migration, and differentiation during corticogenesis. However, the existing studies do not discriminate between embryos with or without neural tube defects, making it difficult to conclude whether the reported changes are related to neural tube defects or other anomalies. Furthermore, postnatal effects on central nervous system cytoarchitecture and function have been scarcely addressed. Through molecular, biochemical, morphological, and electrophysiological approaches, we provide evidence of impaired primary motor cerebral cortex lamination and neuronal function in pups from diabetic rats, showing an altered distribution of SATB2, FOXP2, and TBR1, impaired cell migration and polarity, and decreased excitability of deep-layer cortical neurons, suggesting abnormalities in cortico-cortical and extra-cortical innervation. Furthermore, phase-plot analysis of action potentials suggests changes in the activity of potassium channels. These results indicate that high-glucose insult during development promotes complex changes in migration, neurogenesis, cell polarity establishment, and dendritic arborization, which in turn lead to reduced excitability of deep-layer cortical neurons.

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In this paper, a Microgrid (MG) test model based on the 14-busbar IEEE distribution system is proposed. This model can constitute an important research tool for the analysis of electrical grids in its transition to Smart Grids (SG). The benchmark is used as a base case for power flow analysis and quality variables related with SG and holds distributed resources. The proposed MG consists of DC and AC buses with different types of loads and distributed generation at two voltage levels. A complete model of this MG has been simulated using the MATLAB/Simulink environmental simulation platform. The proposed electrical system will provide a base case for other studies such as: reactive power compensation, stability and inertia analysis, reliability, demand response studies, hierarchical control, fault tolerant control, optimization and energy storage strategies.

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A simple method, based on Machine Learning Radial Basis Functions, RBF, is developed for estimating voltage stability margins in power systems. A reduced set of magnitude and angles of bus voltage phasors is used as input. Observability optimization technique for locating Phasor Measurement Units, PMUs, is applied. A RBF is designed and used for fast calculation of voltage stability margins for online applications with PMUs. The method allows estimating active local and global power margins in normal operation and under contingencies. Optimized placement of PMUs leads to a minimum number of these devices to estimate the margins, but is shown that it is not a matter of PMUs quantity but of PMUs location for decreasing training time or having success in estimation convergence. Compared with previous work, the most significant enhancement is that our RBF learns from PMU data. To test the proposed method, validations in the IEEE 14-bus system and in a real electrical network are done.

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Entre los escasos radioprotectores en uso, la amifostina resulta eficaz para reducir la toxicidad aguda inducida por la radiación ionizante. Sin embargo, presenta efectos tóxicos importantes que impiden su uso repetido o en dosis altas. Es necesario entonces desarrollar radioprotectores menos tóxicos, por sí mismos o como coadyuvantes de la amifostina en dosis bajas. Se expusieron ratas Sprague-Dawley a una dosis de rayos X de 6 Gy (cuerpo entero). Se ensayó el butirato de sodio como mitigante luego de una dosis baja de amifostina previa a la irradiación. A distintos tiempos después de la irradiación se realizó el recuento de eritrocitos, leucocitos y la fórmula leucocitaria. Los efectos genotóxicos se evaluaron en leucocitos de sangre mediante el ensayo Cometa. Se realizaron también estudios de supervivencia a 60 días y la evaluación histológica del duodeno e intestino grueso. El efecto del tratamiento resultó moderadamente protector respecto de la recuperación de los valores normales de eritrocitos, leucocitos y la fórmula leucocitaria en los animales sobrevivientes en ambos sexos, así como de los epitelios intestinales y el ADN de los leucocitos. También aumentó significativamente la sobrevida a 60 días. La radioprotección con amifostina en una dosis baja seguida de una mitigación con butirato fue claramente significativa.

Among the few radioprotectors in use, amifostine is effective in reducing the acute toxicity induced by ionizing radiation. However, it has important toxic effects that prevent its repeated use or in high doses. It is necessary then to develop less toxic radioprotectors, by themselves or as adjuvants of amifostine in low doses. Sprague-Dawley rats were exposed to an X-ray dose of 6 Gy (whole body). Sodium butyrate was tested as a mitigant after a low dose of amifostine prior to irradiation. At different times after the irradiation, the erythrocytes, leukocytes and the leukocyte formula were counted. Genotoxic effects were evaluated in blood leukocytes by the Comet assay. Sixty-day survival studies and histological evaluation of the duodenum and large intestine were also performed. The effect of the treatment was moderately protective with respect to the recovery of the normal values of erythrocytes, leukocytes and the leukocyte formula in the surviving animals in both sexes as well as for the intestinal epithelia and leukocytes DNA. It also significantly increased the 60-day survival. The radioprotection with amifostine in a low dose followed by mitigation with butyrate was clearly significant.

Entre os poucos radioprotetores em uso, a amifostina é eficaz na redução da toxicidade aguda induzida pela radiação ionizante. No entanto, tem importantes efeitos tóxicos que impedem seu uso repetido ou em altas doses. É necessário, então, desenvolver radioprotetores menos tóxicos, isoladamente ou como coadjuvantes da amifostina em baixas doses. Ratos Sprague-Dawley foram expostos a uma dose de raios X de 6 Gy (corpo inteiro). O butirato de sódio foi testado como mitigante após uma dose baixa de amifostina antes da irradiação. Em diferentes momentos após a irradiação, os eritrócitos, leucócitos e a fórmula de leucócitos foram contados. Os efeitos genotóxicos foram avaliados em leucócitos de sangue pelo ensaio Cometa. Estudos de sobrevida de 60 dias e avaliação histológica do duodeno e do intestino grosso também foram realizados. O efeito do tratamento resultou moderadamente protetor em relação à recuperação de valores normais de eritrócitos, leucócitos e fórmula leucocitária nos animais sobreviventes em ambos os sexos, bem como protegeu epitélios intestinais e o DNA dos leucócitos. Também aumentou significativamente a sobrevida para 60 dias. A radioproteção com amifostina em baixa dose seguida de uma mitigação com butirato foi claramente significativa.

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PURPOSE: Complementary and integrative medicine (CIM) use during cancer care has increased in Western medical settings. Little is known about interest in and use of CIM approaches by oncology patients in Chile and South America. PATIENTS AND METHODS: Patients presenting for conventional outpatient or inpatient medical oncology care at the Clinica Alemana in Santiago, Chile, from March to June 2017 were asked to complete a survey about their interest in and use of CIM approaches. Goals included determining the prevalence of CIM use and exploring associations between CIM use and patient characteristics. Statistical analyses included a two-tailed t test for continuous variables, Fischer's exact test for categorical variables, and logistic regression for association between CIM use and other variables. RESULTS: Of 432 patients surveyed, 66.9% were diagnosed with breast cancer, 84.8% were women, the majority of patients (58.1%) were between age 40 and 60 years, and 51.5% (n = 221) reported CIM use. No association was found between CIM use and the sociodemographic variables of sex, age, education, or income. In all, 44.6% of patients with breast cancer reported CIM use compared with 64.8% of patients with other cancer types (P > .001). Most commonly reported types of CIM used included herbals (49.1%), vitamins and minerals (40.8%), and prayer or meditation (40.4%). Most frequent reasons for CIM use were to "do everything possible" (72%) and to "improve my immune function" (67.8%). Most patients (43.4%) reported starting CIM use at the time of cancer diagnosis, with only 55.4% sharing information regarding CIM use with their medical team. CONCLUSION: The majority of patients surveyed reported engaging in CIM use, with just over half the users communicating with their oncology team about their CIM use. Increased awareness of regional differences in CIM use may help increase communication regarding this subject and contribute to improved outcomes.

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Aging is associated with morphological, physiological and metabolic changes, leading to multiorgan degenerative pathologies, such as cognitive function decline. It has been suggested that memory loss also involves a decrease in neurotrophic factors, including brain-derived neurotrophic factor (BDNF). In recent years, microbiota has been proposed as an essential player in brain development, as it is believed to activate BDNF secretion through butyrate production. Thus, microbiota modulation by supplementation with probiotics and prebiotics may impact cognitive decline. This study aimed to evaluate the effects of probiotics and prebiotics supplementation on the memory of middle-aged rats. Sprague-Dawley male rats were randomized in four groups (n = 13 per group): control (water), probiotic (E. faecium), prebiotic (agave inulin), symbiotic (E. faecium + inulin), which were administered for 5 weeks by oral gavage. Spatial and associative memory was analyzed using the Morris Water Maze (MWM) and Pavlovian autoshaping tests, respectively. Hippocampus was obtained to analyze cytokines [interleukin (IL-1ß) and tumor necrosis factor (TNF-α)], BDNF and γ-aminobutyric acid (GABA) by enzyme-linked immunosorbent assay (ELISA). Butyrate concentrations were also evaluated in feces. The symbiotic group showed a significantly better performance in MWM (p < 0.01), but not in Pavlovian autoshaping test. It also showed significantly lower concentrations of pro-inflammatory cytokines (p < 0.01) and the reduction in IL-1ß correlated with a better performance of the symbiotic group in MWM (p < 0.05). Symbiotic group also showed the highest BDNF and butyrate levels (p < 0.0001). Finally, we compared the electrophysiological responses of control (n = 8) and symbiotic (n = 8) groups. Passive properties of CA1 pyramidal cells (PCs) exhibited changes in response to the symbiotic treatment. Likewise, this group showed an increase in the N-methyl-D-aspartate receptor (NMDA)/AMPA ratio and exhibited robust long-term potentiation (LTP; p < 0.01). Integrated results suggest that symbiotics could improve age-related impaired memory.