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Alzheimer's disease (AD) is the most common neurodegenerative disorder worldwide. Histopathologically, AD presents two pathognomonic hallmarks: (1) neurofibrillary tangles, characterized by intracellular deposits of hyperphosphorylated tau protein, and (2) extracellular amyloid deposits (amyloid plaques) in the brain vasculature (cerebral amyloid angiopathy; CAA). It has been proposed that vascular amyloid deposits could trigger neurovascular unit (NVU) dysfunction in AD. The NVU is composed primarily of astrocytic feet, endothelial cells, pericytes, and basement membrane. Although physical exercise is hypothesized to have beneficial effects against AD, it is unknown whether its positive effects extend to ameliorating CAA and improving the physiology of the NVU. We used the triple transgenic animal model for AD (3xTg-AD) at 13 months old and analyzed through behavioral and histological assays, the effect of voluntary physical exercise on cognitive functions, amyloid angiopathy, and the NVU. Our results show that 3xTg-AD mice develop vascular amyloid deposits which correlate with cognitive deficits and NVU alteration. Interestingly, the physical exercise regimen decreases amyloid angiopathy and correlates with an improvement in cognitive function as well as in the underlying integrity of the NVU components. Physical exercise could represent a key therapeutic approach in cerebral amyloid angiopathy and NVU stability in AD patients.

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Alzheimer's disease (AD) is the most common neurodegenerative disease in the world. It is classified as familial and sporadic. The dominant familial or autosomal presentation represents 1-5% of the total number of cases. It is categorized as early onset (EOAD; <65 years of age) and presents genetic mutations in presenilin 1 (PSEN1), presenilin 2 (PSEN2), or the Amyloid precursor protein (APP). Sporadic AD represents 95% of the cases and is categorized as late-onset (LOAD), occurring in patients older than 65 years of age. Several risk factors have been identified in sporadic AD; aging is the main one. Nonetheless, multiple genes have been associated with the different neuropathological events involved in LOAD, such as the pathological processing of Amyloid beta (Aß) peptide and Tau protein, as well as synaptic and mitochondrial dysfunctions, neurovascular alterations, oxidative stress, and neuroinflammation, among others. Interestingly, using genome-wide association study (GWAS) technology, many polymorphisms associated with LOAD have been identified. This review aims to analyze the new genetic findings that are closely related to the pathophysiology of AD. Likewise, it analyzes the multiple mutations identified to date through GWAS that are associated with a high or low risk of developing this neurodegeneration. Understanding genetic variability will allow for the identification of early biomarkers and opportune therapeutic targets for AD.

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High-fat diet (HFD) consumption has been related to metabolic alterations, such as obesity and cardiovascular problems, and has pronounced effects on brain plasticity and memory impairment. HFD exposure has a pro-inflammatory effect associated with microglial cell modifications in the hippocampus, a region involved in the working memory process. Immune tolerance can protect from inflammation in periphery induced by HFD consumption, when the immune response is desensitized in development period with lipopolysaccharide (LPS) exposure, maybe this previously state can change the course of the diseases associated to HFDs but is not known if can protect the hippocampus's inflammatory response. In the present study, male mice were injected with LPS (100 µg.kg-1 body weight) on postnatal day 3 and fed with HFD for 16 weeks after weaning. Ours results indicated that postnatal exposure to LPS in the early postnatal developmental stage combined with HFD consumption prevented glycemia, insulin, HOMA-IR, microglial process, and increased pro-inflammatory cytokines mRNA expression, without changes in body weight gain and spatial working memory with respect vehicle + HFD group. These findings suggest that HFD consumption after postnatal LPS exposure induces hippocampal immune tolerance, without prevention in spatial working memory impairment on male mice.

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BACKGROUND: Amoebiasis is a parasitic disease caused by Entamoeba histolytica, which affects people living in low- and middle-income countries and has intestinal and extraintestinal manifestations. To date, knowledge on coronavirus disease 2019 (COVID-19) coinfection with enteric parasites is limited, and E. histolytica coinfection has not been previously described. Here we present the case of a patient with COVID-19 who, during hospitalisation, presented a clinical picture consistent with an amoebic liver abscess (ALA). CASE PRESENTATION: A 54-year-old man, admitted as a suspected case of COVID-19, presented to our hospital with dyspnoea, malaise, fever and hypoxaemia. A nasopharyngeal swab was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse-transcription polymerase chain reaction. After 7 days, he developed diarrhoea, choluria and dysentery. An abdominal ultrasound showed a lesion compatible with a liver abscess; stool examination revealed E. histolytica trophozoites, and additional serology for E. histolytica was positive. After 12 days of treatment with metronidazole, ceftazidime and nitazoxanide, the patient reported acute abdominal pain, and an ultrasound examination revealed free liquid in the abdominal cavity. An emergency exploratory laparotomy was performed, finding 3000 mL of a thick fluid described as "anchovy paste". Computed tomography scan revealed a second abscess. He ended up receiving 21 days of antibiotic treatment and was discharged with satisfactory improvement. CONCLUSION: Here we present, to the best of our knowledge, the first report of ALA and COVID-19 co-presenting. Based on their pathophysiological similarities, coinfection with SARS-CoV-2 and E. histolytica could change the patient's clinical course; however, larger studies are needed to fully understand the interaction between these pathogens.

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PURPOSE: Research suggests that ethnicity is a predictor of pain-related outcomes; however, studies comparing the differences in experimental pain sensitivity between Hispanics and non-Hispanic Whites (NHW) are scarce. This study investigated these differences between Hispanics and NHW from the U.S.- Mexico border. METHODS: Fifty-eight healthy participants completed the survey packet, which included a demographic and a psychosocial factors questionnaire. Participants underwent quantitative sensory testing, which included heat pain threshold, heat pain tolerance, Suprathreshold Heat Pain Response (SHPR), and Conditioned Pain Modulation (CPM). SHPR was induced by repeated thermal stimuli in both thenar eminences. CPM was assessed using SHPR as the experimental stimulus and cold pressor task as the conditioning stimulus. RESULTS: Analyses showed significant differences in experimental pain measures believed to be representative of facilitatory pain processing including SHPR and heat pain threshold, where Hispanics reported significantly higher pain ratings than NHW. Hispanics also reported higher levels of ethnic identity and acculturation. However, these factors were not significantly associated with experimental pain sensitivity. CONCLUSION: The experimental pain sensitivity and psychosocial factors included in this study differed by ethnic group, where Hispanics reported significantly higher pain ratings, when compared with NHW. However, ethnic identity and acculturation were not associated with these pain-related outcomes. Overall, enhanced understanding by clinicians of pain sensitivity and disparities in the pain experience between ethnic groups allows for increased cultural sensitivity and can be used to optimize pain treatment on an individual-by-individual basis.

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The regeneration niche concept states that plant species only occur in habitats where the environmental conditions allow their recruitment. This study focuses on this concept and proposes a novel approach for modelling and experimentally validating the distribution of suitable habitats for the recruitment of invasive plants under the current and future climate. The biological invasion of the Peruvian peppertree (Schinus molle) in Mexico is used as practical example. The values of eight bioclimatic variables associated to sites in which young, naturally established seedlings and saplings were detected were used to model the current distribution of recruitment habitats. A machine-learning algorithm of maximum entropy (MaxEnt) was used to calibrate the model and its output indicated the distribution of occurrence probabilities of young peppertrees in Mexico under the current climate. This model was projected on climate change scenarios predicted for the middle of this century, which indicated that the cover of suitable recruitment habitats for this invasive species will shrink. To validate these predictions, field experiments were performed at three sites where the model predicted reduced occurrence probabilities of young peppertrees. In these experiments, emergence and survival rates of peppertree seedlings were assessed under the current climate and under simulated climate change conditions. As seedling emergence and survival rates were lower under simulated climate change conditions, the experiments validated the model predictions. These results supported our proposal, which combines modelling and experimental approaches to make accurate and valid predictions about the distribution of suitable recruitment habitats for invasive plants in a warmer and drier world.

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The suitability of dispersive liquid-liquid microextraction (DLLME) and gas chromatography accurate mass spectrometry (GC-MS), based on a time-of-flight (TOF) MS analyzer and using electron ionization (EI), for the characterization of volatile and semi-volatile profiles of grape marc distillates (grappa) are evaluated. DLLME conditions are optimized with a selection of compounds, from different chemical families, present in the distillate spirit. Under final working conditions, 2.5 mL of sample and 0.5 mL of organic solvents are consumed in the sample preparation process. The absolute extraction efficiencies ranged from 30 to 100%, depending on the compound. For the same sample volume, DLLME provided higher responses than solid-phase microextraction (SPME) for most of the model compounds. The GC-EI-TOF-MS records of grappa samples were processed using a data mining non-targeted search algorithm. In this way, chromatographic peaks and accurate EI-MS spectra of sample components were linked. The identities of more than 140 of these components are proposed from comparison of their accurate spectra with those in a low resolution EI-MS database, accurate masses of most intense fragment ions of known structure, and available chromatographic retention index. The use of chromatographic and spectral data, associated to the set of components mined from different grappa samples, for multivariate analysis purposes is also illustrated in the study.

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Diabetic macular edema can occur at any stage of diabetic retinopathy. It represents the main cause of vision loss in diabetes type I and II with a prevalence of 3-10% in diabetic patients of the Instituto Mexicano del Seguro Social (IMSS). Our aim is to elaborate treatment guidelines and provide recommendations for the use of intravitreal ranibizumab for diabetic medical edema at IMSS. Nine retina specialists and 10 ophthalmologists from IMSS high specialty medical units gathered to discuss the bibliographic evidence for the safety and efficacy of ranibizumab for this disease, in order to create consensus on its use in the institution. Intravitreal ranibizumab injection should be used on patients presenting diffuse or cystic diabetic macular edema who have strict metabolic control and visual acuity between 20/30 and 20/200 ETDRS, as well as structural features, such as inferior foveal limit of 280 µm and ischemic areas no larger than 50% of the central foveal area. Treatment regime should consist of a loading charge of three monthly injections of ranibizumab 0.5 mg, followed by monthly follow-ups and treatment as needed according to anatomic and functional criteria. This consensus decision-making process on the criteria to treat and re-treat patients with this drug will result in better health outcomes than those currently observed among patients with diabetic macular edema at IMSS.

El edema macular diabético se presenta en cualquier etapa de la retinopatía diabética y representa la principal causa de pérdida de visión en las diabetes tipo I y II, con una prevalencia que va del 3 al 10% en pacientes diabéticos del Instituto Mexicano del Seguro Social (IMSS). El objetivo de este trabajo es elaborar una guía de tratamiento y recomendaciones para el uso de ranibizumab intravítreo en pacientes con edema macular diabético en el IMSS. Se llevó a cabo una reunión de expertos (9 retinólogos y 10 oftalmólogos) de las unidades médicas de alta especialidad del IMSS para realizar una revisión crítica de la eficacia y seguridad del ranibizumab para esta enfermedad y llegar a un consenso sobre el uso de este antiangiogénico en la institución. Las inyecciones de ranibizumab intravítreo se aplicarían a pacientes con edema macular diabético del tipo difuso o quístico, con un control metabólico estricto, agudeza visual en un rango de 20/30 a 20/200 ETDRS y criterios estructurales, como el límite foveal inferior a 280 µm y zonas isquémicas de no más del 50% de la zona central foveal. El esquema de tratamiento consistiría en una dosis de carga de tres inyecciones mensuales de ranibizumab de 0.5 mg y posteriormente seguimiento mensual y tratamiento por razón necesaria según criterios anatómicos y funcionales. El consenso sobre los criterios de tratamiento y retratamiento con este medicamento garantizará mejores resultados clínicos en pacientes con edema macular diabético en el IMSS.

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Como universidad pública, la Universidad AutónomaGabriel René Moreno ingresa al debate sobre la cuestión nacional, con una propuesta sobre la necesidad de construir en Bolivia un Estado autonómico e intercultural. Esto es, un debate que permita refundar el Estado conciliando los intereses de lasociedad civil con la sociedad política, mediante la Asamblea Constituyente encargada de redactar la nueva Constitución Política del Estado.

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Como universidad pública, la Universidad AutónomaGabriel René Moreno ingresa al debate sobre la cuestión nacional, con una propuesta sobre la necesidad de construir en Bolivia un Estado autonómico e intercultural. Esto es, un debate que permita refundar el Estado conciliando los intereses de lasociedad civil con la sociedad política, mediante la Asamblea Constituyente encargada de redactar la nueva Constitución Política del Estado.

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