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1.
J Alzheimers Dis ; 97(3): 1101-1104, 2024.
Article En | MEDLINE | ID: mdl-38189754

Alzheimer's disease is a multi-factorial disease that disrupts many aspects of human behavior. In this comment, we highlight the work by Koulousakis et al. published in a recent issue of the Journal of Alzheimer's Disease. In this study, the authors tested the therapeutic potential of the neuropeptide oxytocin in a pre-clinical model of Alzheimer's disease and found positive behavioral outcomes on memory assessments. We discuss these findings in the context of oxytocin research in the field of Alzheimer's disease and the literature regarding oxytocin-based therapeutics, including administration protocols and potential underlying cellular and molecular mechanisms.


Alzheimer Disease , Humans , Alzheimer Disease/drug therapy , Oxytocin/therapeutic use , Amyloid beta-Peptides , Cognition
2.
Neurobiol Dis ; 187: 106308, 2023 Oct 15.
Article En | MEDLINE | ID: mdl-37741513

Tissue-resident memory CD8 T cells are responsible for local immune surveillance in different tissues, including the brain. They constitute the first line of defense against pathogens and cancer cells and play a role in autoimmunity. A recently published study demonstrated that CD8 T cells with markers of residency containing distinct granzymes and interferon-γ infiltrate the parenchyma of the substantia nigra and contact dopaminergic neurons in an early premotor stage of Parkinson's disease. This infiltration precedes α-synuclein aggregation and neuronal loss in the substantia nigra, suggesting a relevant role for CD8 T cells in the onset of the disease. To date, the nature of the antigen that initiates the adaptive immune response remains unknown. This review will discuss the role of tissue-resident memory CD8 T cells in brain immune homeostasis and in the onset of Parkinson's disease and other neurological diseases. We also discuss how aging and genetic factors can affect the CD8 T cell immune response and how animal models can be misleading when studying human-related immune response. Finally, we speculate about a possible infectious or autoimmune origin of Parkinson's disease.

3.
iScience ; 26(4): 106545, 2023 Apr 21.
Article En | MEDLINE | ID: mdl-37128547

Alzheimer's disease (AD) is characterized by neurodegeneration, memory loss, and social withdrawal. Brain inflammation has emerged as a key pathogenic mechanism in AD. We hypothesized that oxytocin, a pro-social hypothalamic neuropeptide with anti-inflammatory properties, could have therapeutic actions in AD. Here, we investigated oxytocin expression in experimental models of AD, and evaluated the therapeutic potential of treatment with oxytocin. Amyloid-ß peptide oligomers (AßOs) reduced oxytocin expression in vitro and in vivo, and treatment with oxytocin prevented microglial activation induced by AßOs in purified microglial cultures. Treatment of aged APP/PS1 mice, a mouse model of AD, with intranasal oxytocin attenuated microglial activation and favored deposition of Aß in dense core plaques, a potentially neuroprotective mechanism. Remarkably, treatment with oxytocin alleviated social and non-social memory impairments in aged APP/PS1 mice. Our findings point to oxytocin as a potential therapeutic target to reduce brain inflammation and correct memory deficits in AD.

4.
Mol Ther ; 31(2): 409-419, 2023 02 01.
Article En | MEDLINE | ID: mdl-36369741

The accumulation of soluble oligomers of the amyloid-ß peptide (AßOs) in the brain has been implicated in synapse failure and memory impairment in Alzheimer's disease. Here, we initially show that treatment with NUsc1, a single-chain variable-fragment antibody (scFv) that selectively targets a subpopulation of AßOs and shows minimal reactivity to Aß monomers and fibrils, prevents the inhibition of long-term potentiation in hippocampal slices and memory impairment induced by AßOs in mice. As a therapeutic approach for intracerebral antibody delivery, we developed an adeno-associated virus vector to drive neuronal expression of NUsc1 (AAV-NUsc1) within the brain. Transduction by AAV-NUsc1 induced NUsc1 expression and secretion in adult human brain slices and inhibited AßO binding to neurons and AßO-induced loss of dendritic spines in primary rat hippocampal cultures. Treatment of mice with AAV-NUsc1 prevented memory impairment induced by AßOs and, remarkably, reversed memory deficits in aged APPswe/PS1ΔE9 Alzheimer's disease model mice. These results support the feasibility of immunotherapy using viral vector-mediated gene delivery of NUsc1 or other AßO-specific single-chain antibodies as a potential therapeutic approach in Alzheimer's disease.


Alzheimer Disease , Single-Chain Antibodies , Mice , Rats , Humans , Animals , Aged , Alzheimer Disease/genetics , Alzheimer Disease/therapy , Alzheimer Disease/metabolism , Single-Chain Antibodies/genetics , Single-Chain Antibodies/metabolism , Amyloid beta-Peptides/genetics , Amyloid beta-Peptides/metabolism , Synapses/metabolism , Neurons/metabolism , Memory Disorders/genetics , Memory Disorders/therapy
5.
Sci Rep ; 12(1): 9797, 2022 06 13.
Article En | MEDLINE | ID: mdl-35697727

An interesting evolutionary question that still remains open is the connectivity between marine populations. Marine currents can favour the dispersal of larvae or adults, but they can also produce eddies and gyres generating oceanographic fronts, thus limiting gene flow. To address this subject, we selected the Atlantic-Mediterranean transition, where several fronts are located: Gibraltar Strait (GS), Almeria-Oran Front (AOF) and Ibiza Channel (IC). Seven populations of the marine crab Liocarcinus depurator (Cadiz, West and East Alboran, Alacant, Valencia, Ebro Delta and North Catalonia) located along this transition were analysed in six consecutive years (2014-2019) using a fragment of the COI (Cytochrome Oxidase subunit I) gene. All sequences (966) belonged to two well defined haplogroups: ATL (most abundant in Atlantic waters) and MED (predominant in Mediterranean waters). Following a geographic variation, the frequency of ATL decreased significantly from Cadiz to North Catalonia. However, this variation presented steps due to the effect of oceanographic restrictions/fronts. Significant effects were recorded for GS (2015, 2017, 2018 and 2019), AOF (all years except 2018) and IC (2016). The intensity and precise location of these fronts changed over time. Multivariate analyses distinguished three main population groups: Cadiz, Alboran Sea and the remaining Mediterranean populations. These findings could be relevant to properly define Marine Protected Areas and for conservation and fisheries policies.


Brachyura/physiology , Animals , Atlantic Ocean , Biological Evolution , Brachyura/genetics , Conservation of Natural Resources , Electron Transport Complex IV/genetics , Environmental Policy , Fisheries/standards , Gene Flow , Genetic Variation , Humans , Mediterranean Sea , Policy Making , Water Movements
6.
Rev. bras. ter. intensiva ; 33(3): 362-373, jul.-set. 2021. tab, graf
Article En, Es | LILACS | ID: biblio-1347301

RESUMEN Objetivo: Determinar la efectividad de la ventilación no invasiva frente a oxigenoterapia convencional en pacientes con insuficiencia respiratoria aguda tras fracaso de la extubación. Métodos: Ensayo clínico pragmático realizado una unidad de cuidados intensivos de marzo de 2009 a septiembre de 2016. Se incluyeron pacientes sometidos a ventilación mecánica > 24 horas, y que desarrollaron insuficiencia respiratoria aguda tras extubación programada, siendo asignados a ventilación no invasiva u oxigenoterapia convencional. El objetivo primario fue reducir la tasa de reintubación. Los objetivos secundarios fueron: mejora de los parámetros respiratorios, reducción de las complicaciones, de la duración de la ventilación mecánica, de la estancia en unidad de cuidados intensivos y hospitalaria, así como de la mortalidad en unidad de cuidados intensivos, hospitalaria y a los 90 días. También se analizaron los factores relacionados con la reintubación. Resultados: De un total de 2.574 pacientes, se analizaron 77 (38 en el grupo de ventilación no invasiva y 39 en el grupo de oxigenoterapia convencional). La ventilación no invasiva redujo la frecuencia respiratoria y cardíaca más rápidamente que la oxigenoterapia convencional. La reintubación fue menor en el grupo de ventilación no invasiva [12 (32%) versus 22(56%) en grupo oxigenoterapia convencional, RR 0,58 (IC95% 0,34 - 0,97), p = 0,039], el resto de los parámetros no mostró diferencias significativas. En el análisis multivariante, la ventilación no invasiva prevenía la reintubación [OR 0,17 (IC95% 0,05 - 0,56), p = 0,004], mientras que el fracaso hepático previo a la extubación y la incapacidad para mantener vía aérea permeable predisponían a la reintubación. Conclusión: El empleo de la ventilación no invasiva en pacientes que fracasa la extubación podría ser beneficiosa frente a la oxigenoterapia convencional.


ABSTRACT Objective: To determine the effectiveness of noninvasive ventilation versus conventional oxygen therapy in patients with acute respiratory failure after extubation failure. Methods: A pragmatic clinical trial was conducted in an intensive care unit from March 2009 to September 2016. Patients on mechanical ventilation > 24 hours who developed acute respiratory failure after scheduled extubation were included and were assigned to noninvasive ventilation or conventional oxygen therapy. The primary objective was to reduce the reintubation rate. The secondary objectives were to improve respiratory parameters and reduce complications, the duration of mechanical ventilation, the intensive care unit stay, the hospital stay, and mortality in the intensive care unit, in the hospital, and 90 days after discharge. Factors correlated with reintubation were also analyzed. Results: Of a total of 2,574 patients, 77 were analyzed (38 in the noninvasive ventilation group and 39 in the conventional oxygen therapy group). Noninvasive ventilation reduced the respiratory and cardiac rates more rapidly than conventional oxygen therapy. Reintubation was less common in the noninvasive ventilation group [12 (32%) versus 22 (56%) in the conventional oxygen therapy group, relative risk 0.58 (95%CI 0.34 - 0.97), p = 0.039]. The rest of the parameters did not show significant differences. In the multivariate analysis, noninvasive ventilation protected against reintubation [OR 0.17 (95%CI 0.05 - 0.56), p = 0.004], while liver failure before extubation and the inability to maintain airway patency predisposed patients to reintubation. Conclusion: The use of noninvasive ventilation in patients who failed extubation could be beneficial compared to conventional oxygen therapy.


Humans , Airway Extubation , Noninvasive Ventilation , Oxygen , Respiration, Artificial , Intensive Care Units
7.
Rev Bras Ter Intensiva ; 33(3): 362-373, 2021.
Article Es, En | MEDLINE | ID: mdl-35107547

OBJECTIVE: To determine the effectiveness of noninvasive ventilation versus conventional oxygen therapy in patients with acute respiratory failure after extubation failure. METHODS: A pragmatic clinical trial was conducted in an intensive care unit from March 2009 to September 2016. Patients on mechanical ventilation > 24 hours who developed acute respiratory failure after scheduled extubation were included and were assigned to noninvasive ventilation or conventional oxygen therapy. The primary objective was to reduce the reintubation rate. The secondary objectives were to improve respiratory parameters and reduce complications, the duration of mechanical ventilation, the intensive care unit stay, the hospital stay, and mortality in the intensive care unit, in the hospital, and 90 days after discharge. Factors correlated with reintubation were also analyzed. RESULTS: Of a total of 2,574 patients, 77 were analyzed (38 in the noninvasive ventilation group and 39 in the conventional oxygen therapy group). Noninvasive ventilation reduced the respiratory and cardiac rates more rapidly than conventional oxygen therapy. Reintubation was less common in the noninvasive ventilation group [12 (32%) versus 22 (56%) in the conventional oxygen therapy group, relative risk 0.58 (95%CI 0.34 - 0.97), p = 0.039]. The rest of the parameters did not show significant differences. In the multivariate analysis, noninvasive ventilation protected against reintubation [OR 0.17 (95%CI 0.05 - 0.56), p = 0.004], while liver failure before extubation and the inability to maintain airway patency predisposed patients to reintubation. CONCLUSION: The use of noninvasive ventilation in patients who failed extubation could be beneficial compared to conventional oxygen therapy.


OBJETIVO: Determinar la efectividad de la ventilación no invasiva frente a oxigenoterapia convencional en pacientes con insuficiencia respiratoria aguda tras fracaso de la extubación. MÉTODOS: Ensayo clínico pragmático realizado una unidad de cuidados intensivos de marzo de 2009 a septiembre de 2016. Se incluyeron pacientes sometidos a ventilación mecánica > 24 horas, y que desarrollaron insuficiencia respiratoria aguda tras extubación programada, siendo asignados a ventilación no invasiva u oxigenoterapia convencional. El objetivo primario fue reducir la tasa de reintubación. Los objetivos secundarios fueron: mejora de los parámetros respiratorios, reducción de las complicaciones, de la duración de la ventilación mecánica, de la estancia en unidad de cuidados intensivos y hospitalaria, así como de la mortalidad en unidad de cuidados intensivos, hospitalaria y a los 90 días. También se analizaron los factores relacionados con la reintubación. RESULTADOS: De un total de 2.574 pacientes, se analizaron 77 (38 en el grupo de ventilación no invasiva y 39 en el grupo de oxigenoterapia convencional). La ventilación no invasiva redujo la frecuencia respiratoria y cardíaca más rápidamente que la oxigenoterapia convencional. La reintubación fue menor en el grupo de ventilación no invasiva [12 (32%) versus 22(56%) en grupo oxigenoterapia convencional, RR 0,58 (IC95% 0,34 - 0,97), p = 0,039], el resto de los parámetros no mostró diferencias significativas. En el análisis multivariante, la ventilación no invasiva prevenía la reintubación [OR 0,17 (IC95% 0,05 - 0,56), p = 0,004], mientras que el fracaso hepático previo a la extubación y la incapacidad para mantener vía aérea permeable predisponían a la reintubación. CONCLUSIÓN: El empleo de la ventilación no invasiva en pacientes que fracasa la extubación podría ser beneficiosa frente a la oxigenoterapia convencional.


Airway Extubation , Noninvasive Ventilation , Humans , Intensive Care Units , Oxygen , Respiration, Artificial
8.
J Neurochem ; 153(1): 10-32, 2020 04.
Article En | MEDLINE | ID: mdl-31630412

Perception of our environment entirely depends on the close interaction between the central and peripheral nervous system. In order to communicate each other, both systems must develop in parallel and in coordination. During development, axonal projections from the CNS as well as the PNS must extend over large distances to reach their appropriate target cells. To do so, they read and follow a series of axon guidance molecules. Interestingly, while these molecules play critical roles in guiding developing axons, they have also been shown to be critical in other major neurodevelopmental processes, such as the migration of cortical progenitors. Currently, a major hurdle for brain repair after injury or neurodegeneration is the absence of axonal regeneration in the mammalian CNS. By contrasts, PNS axons can regenerate. Many hypotheses have been put forward to explain this paradox but recent studies suggest that hacking neurodevelopmental mechanisms may be the key to promote CNS regeneration. Here we provide a seminar report written by trainees attending the second Flagship school held in Alpbach, Austria in September 2018 organized by the International Society for Neurochemistry (ISN) together with the Journal of Neurochemistry (JCN). This advanced school has brought together leaders in the fields of neurodevelopment and regeneration in order to discuss major keystones and future challenges in these respective fields.


Axon Guidance/physiology , Axons/physiology , Brain/ultrastructure , Animals , Axons/ultrastructure , Brain/growth & development , Brain/physiology , Humans , Nerve Regeneration , Optic Chiasm/growth & development , Peripheral Nervous System/growth & development , Peripheral Nervous System/physiology , Spinal Cord/growth & development , Spinal Cord/physiology , Spinal Cord/ultrastructure
9.
Mol Neurobiol ; 57(3): 1473-1483, 2020 Mar.
Article En | MEDLINE | ID: mdl-31760608

Alzheimer's disease (AD) is the main cause of dementia in the elderly. Although activation of brain insulin signaling has been shown to be neuroprotective, to preserve memory in AD models, and appears beneficial in patients, the role of insulin-like growth factor 1 (IGF1) remains incompletely understood. We found reduced active/inactive IGF1 ratio and increased IGF1R expression in postmortem hippocampal tissue from AD patients, suggesting impaired brain IGF1 signaling in AD. Active/inactive IGF-1 ratio was also reduced in the brains of mouse models of AD. We next investigated the possible protective role of IGF1 in AD models. We used a recombinant adenoviral vector, RAd-IGF1, to drive the expression of IGF1 in primary hippocampal neuronal cultures prior to exposure to AßOs, toxins that accumulate in AD brains and have been implicated in early synapse dysfunction and memory impairment. Cultures transduced with RAd-IGF1 showed decreased binding of AßOs to neurons and were protected against AßO-induced neuronal oxidative stress and loss of dendritic spines. Significantly, in vivo transduction with RAd-IGF1 blocked memory impairment caused by intracerebroventricular (i.c.v.) infusion of AßOs in mice. Our results demonstrate altered active IGF1 and IGF1R levels in AD hippocampi, and suggest that boosting brain expression of IGF1 may comprise an approach to prevent neuronal damage and memory loss in AD.


Adenoviridae/pathogenicity , Alzheimer Disease/metabolism , Hippocampus/metabolism , Insulin-Like Growth Factor I/metabolism , Memory Disorders/prevention & control , Adenoviridae/metabolism , Aged , Aged, 80 and over , Alzheimer Disease/virology , Amyloid beta-Peptides/metabolism , Animals , Disease Models, Animal , Female , Humans , Male , Memory/physiology , Memory Disorders/metabolism , Mice , Neurons/metabolism , Synapses/metabolism
11.
J Neurosci Methods ; 307: 203-209, 2018 09 01.
Article En | MEDLINE | ID: mdl-29859877

BACKGROUND: Slice cultures have been prepared from several organs. With respect to the brain, advantages of slice cultures over dissociated cell cultures include maintenance of the cytoarchitecture and neuronal connectivity. Slice cultures from adult human brain have been reported and constitute a promising method to study neurological diseases. Despite this potential, few studies have characterized in detail cell survival and function along time in short-term, free-floating cultures. NEW METHOD: We used tissue from adult human brain cortex from patients undergoing temporal lobectomy to prepare 200 µm-thick slices. Along the period in culture, we evaluated neuronal survival, histological modifications, and neurotransmitter release. The toxicity of Alzheimer's-associated Aß oligomers (AßOs) to cultured slices was also analyzed. RESULTS: Neurons in human brain slices remain viable and neurochemically active for at least four days in vitro, which allowed detection of binding of AßOs. We further found that slices exposed to AßOs presented elevated levels of hyperphosphorylated Tau, a hallmark of Alzheimer's disease. COMPARISON WITH EXISTING METHOD(S): Although slice cultures from adult human brain have been previously prepared, this is the first report to analyze cell viability and neuronal activity in short-term free-floating cultures as a function of days in vitro. CONCLUSIONS: Once surgical tissue is available, the current protocol is easy to perform and produces functional slices from adult human brain. These slice cultures may represent a preferred model for translational studies of neurodegenerative disorders when long term culturing in not required, as in investigations on AßO neurotoxicity.


Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/pharmacology , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Neurons/metabolism , Neurotransmitter Agents/metabolism , Adult , Analysis of Variance , Epilepsy, Temporal Lobe/pathology , Female , Humans , In Vitro Techniques , Male , Middle Aged , Organ Culture Techniques , Phosphopyruvate Hydratase/metabolism , Potassium Chloride/pharmacology , tau Proteins/metabolism
13.
Mycol Res ; 113(5): 602-10, 2009 May.
Article En | MEDLINE | ID: mdl-19640401

A multiplex PCR method has been developed to detect, differentiate, and confirm the morphological identification of three root infecting Olpidium spp.: O. bornovanus, O. brassicae, and O. virulentus. Of the 132 root samples examined, 101 samples were infected by Olpidium spp.. Based on the morphology of resting spores, the presence of O. bornovanus was confirmed in 20.5% of the samples, whereas species identity could not be determined for the remaining samples because they failed to reproduce sexually. With multiplex PCR, it was possible to determine the Olpidium identity of all the infected samples, even when resting spores were not formed. This method was also effective for detecting Olpidium spp. in water samples. In addition, the specificity and sensitivity of multiplex PCR were evaluated. The multiplex PCR method was validated with samples of 9 different crops from 11 countries of America, Europe, and Africa.


Chytridiomycota/classification , Chytridiomycota/genetics , Polymerase Chain Reaction/methods , DNA, Fungal/analysis , Mycological Typing Techniques , Sensitivity and Specificity
14.
Plant Dis ; 91(10): 1250-1254, 2007 Oct.
Article En | MEDLINE | ID: mdl-30780522

Rates of seed transmission for Pepino mosaic virus (PepMV) were estimated in seedlings grown from seeds obtained from symptomatic tomato (Lycopersicon esculentum) fruits of plants naturally infected with the virus. The proportion of seeds infected with PepMV was at least 25% as estimated from enzyme-linked immunosorbent assay (ELISA) analysis of grouped seeds. The seeds from symptomatic fruits were planted, and seedlings at the cotyledon and transplant stage were assayed for PepMV by ELISA. Three of 168 seedlings grown from infected seeds were PepMV-positive, corresponding to a seed-to-seedling transmission rate of 1.84%. Various tomato seed treatments were evaluated for their ability to prevent seed transmission of PepMV. This virus was largely eradicated by immersing the seeds in 10% trisodium phosphate for 3 h. Although heat treatments of 24 h at 80°C and 48 h at 74°C eliminated PepMV in seedlings, these treatments did not eradicate the virus in whole seeds. The three treatments did not adversely affect seed germination. The results suggest that trisodium phosphate can be used to eradicate PepMV in tomato seed without hindering germination.

15.
Phytopathology ; 96(3): 274-9, 2006 Mar.
Article En | MEDLINE | ID: mdl-18944442

ABSTRACT The population structure of Pepino mosaic virus (PepMV), which has caused severe epidemics in tomato in Spain since 2000, was analyzed. Isolates were characterized by the nucleotide sequence of the triple gene block and coat protein gene and, for a subset of isolates, a part of the RNA-dependent RNA polymerase gene. The full-length sequence of the genomic RNA of a Solanum muricatum isolate from Peru also was determined. In spite of high symptom diversity, the Spanish population of PepMV mostly comprised highly similar isolates belonging to the strain reported in Europe (European tomato strain), which has been the most prevalent genotype in Spain. The Spanish PepMV population was not structured spatially or temporally. Also, isolates highly similar to those from nontomato hosts from Peru (Peruvian strain) or to isolate US2 from the United States (US2 strain) were detected at lower frequency relative to the European strain. These two strains were detected in peninsular Spain only in 2004, but the Peruvian strain has been detected in the Canary Islands since 2000. These results suggest that PepMV was introduced into Spain more than once. Isolates from the Peruvian and US2 strains always were found in mixed infections with the European tomato strain, and interstrain recombinants were detected. The presence of different strains of the virus, and of recombinant isolates, should be considered for the development of control strategies based on genetic resistance.

16.
Hybrid Hybridomics ; 21(6): 487-90, 2002 Dec.
Article En | MEDLINE | ID: mdl-12573113

A monoclonal antibody (MAb) directed against human immunoaffinity purified trypsinogen has been produced by hybridization of myeloma cells with spleen cells of BALB/c immunized mice. Antibodies were screened by ultramicro-enzyme-linked immunosorbent assay (UMELISA). The MAb was purified by affinity chromatography on protein A-sepharose, and MAb had a high affinity for trypsinogen with the affinity constant equal 2.06 x 10(9) L/mol. Specificity was studied by UMELISA using cross-reactant proteins; MAb gave a positive reaction with native trypsinogen-1 but did not react with the same protein after reduction. The antibody seem to be directed against conformational epitope. The MAb obtained was characterized immunologically and used to develop UMELISA for detection Trypsin. This monoclonal assay enabled the detection of 2.8 ng/mL.


Antibodies, Monoclonal/immunology , Trypsin/immunology , Animals , Cystic Fibrosis/diagnosis , Enzyme-Linked Immunosorbent Assay , Humans , Infant, Newborn , Mice , Mice, Inbred BALB C , Neonatal Screening , Trypsin/analysis , Trypsin/blood , Trypsinogen/analysis , Trypsinogen/blood , Trypsinogen/immunology
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