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1.
JAMA ; 331(17): 1512, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38602706

RESUMO

This JAMA Patient Page describes the types of flat head syndrome and its prevention and treatment.


Assuntos
Craniossinostoses , Humanos , Lactente , Recém-Nascido , Craniossinostoses/diagnóstico , Craniossinostoses/prevenção & controle , Craniossinostoses/terapia , Cabeça/anormalidades , Dispositivos de Proteção da Cabeça , Síndrome
2.
Cell Mol Life Sci ; 81(1): 181, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615095

RESUMO

In vertebrates, oligodendrocytes (OLs) are glial cells of the central nervous system (CNS) responsible for the formation of the myelin sheath that surrounds the axons of neurons. The myelin sheath plays a crucial role in the transmission of neuronal information by promoting the rapid saltatory conduction of action potentials and providing neurons with structural and metabolic support. Saltatory conduction, first described in the peripheral nervous system (PNS), is now generally recognized as a universal evolutionary innovation to respond quickly to the environment: myelin helps us think and act fast. Nevertheless, the role of myelin in the central nervous system, especially in the brain, may not be primarily focused on accelerating conduction speed but rather on ensuring precision. Its principal function could be to coordinate various neuronal networks, promoting their synchronization through oscillations (or rhythms) relevant for specific information processing tasks. Interestingly, myelin has been directly involved in different types of cognitive processes relying on brain oscillations, and myelin plasticity is currently considered to be part of the fundamental mechanisms for memory formation and maintenance. However, despite ample evidence showing the involvement of myelin in cognition and neurodevelopmental disorders characterized by cognitive impairments, the link between myelin, brain oscillations, cognition and disease is not yet fully understood. In this review, we aim to highlight what is known and what remains to be explored to understand the role of myelin in high order brain processes.


Assuntos
Bainha de Mielina , Transtornos do Neurodesenvolvimento , Animais , Cognição , Sistema Nervoso Central , Encéfalo
4.
Protoplasma ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421489

RESUMO

Chrysolaena flexuosa (Sims.) H. Rob. is a South American species in the tribe Vernonieae, with potential ornamental value: it has attractive inflorescences, is suitable for pot cultivation, and its cypselae are useful for dried flower arrangements. Apart from studies on the growth dynamics of this species under cultivation, chromosome number, DNA content, ploidy level, size, pollen viability, and the characterization of phenotypic and genetic variability, it is noteworthy that other aspects regarding the floral architecture, reproductive mode, and gametophyte formation of C. flexuosa have not yet been studied. For this reason, our study encompasses a floral morphoanatomical survey and a comprehensive assessment of gametophyte development in the species. As a result of this study, we report new floral morphotypes, confirming that the morphological variability of the species might be greater than speculated. The morphoanatomy of the androecium and gynoecium and the male and female gametophyte developmental characteristics are uniform in all the populations studied despite the different ploidy levels. Chrysolaena flexuosa has five tetrasporangiate stamens of the dicotyledonous type of development; all the populations studied displayed a unilocular inferior ovary with a single anatropous, unitegumented, and tenuinucellar ovule. Given that all the embryo sacs observed were of the Polygonum-type development regardless of the ploidy level, we infer that the populations analyzed are fertile and undergo sexual reproduction. Our results not only contribute further research in the field of breeding systems and propagation of this species, but also promote the successful introduction of C. flexuosa to the plant ornamental market.

5.
Cell Mol Life Sci ; 81(1): 15, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38194116

RESUMO

Although intracellular Ca2+ signals of oligodendroglia, the myelin-forming cells of the central nervous system, regulate vital cellular processes including myelination, few studies on oligodendroglia Ca2+ signal dynamics have been carried out and existing software solutions are not adapted to the analysis of the complex Ca2+ signal characteristics of these cells. Here, we provide a comprehensive solution to analyze oligodendroglia Ca2+ imaging data at the population and single-cell levels. We describe a new analytical pipeline containing two free, open source and cross-platform software programs, Occam and post-prOccam, that enable the fully automated analysis of one- and two-photon Ca2+ imaging datasets from oligodendroglia obtained by either ex vivo or in vivo Ca2+ imaging techniques. Easily configurable, our software solution is optimized to obtain unbiased results from large datasets acquired with different imaging techniques. Compared to other recent software, our solution proved to be fast, low memory demanding and faithful in the analysis of oligodendroglial Ca2+ signals in all tested imaging conditions. Our versatile and accessible Ca2+ imaging data analysis tool will facilitate the elucidation of Ca2+-mediated mechanisms in oligodendroglia. Its configurability should also ensure its suitability with new use cases such as other glial cell types or even cells outside the CNS.


Assuntos
Cálcio , Oligodendroglia , Fluxo de Trabalho , Bainha de Mielina , Neuroglia
6.
Salud Publica Mex ; 65(3, may-jun): 253-264, 2023 Apr 21.
Artigo em Espanhol | MEDLINE | ID: mdl-38060880

RESUMO

OBJETIVO: Estimar la prevalencia e identificar determinantes de la infección por el virus del papiloma humano (VPH) en mujeres jóvenes (18-25 años). Material y métodos. Se analizaron datos de 5 871 mujeres sexualmente activas a quienes se les realizó una entrevista y toma de muestras cervicouterinas para detección de VPH y citología durante la visita de reclutamiento del Ensayo de Vacunación contra VPH16/18 en Costa Rica. Se calculó la prevalencia total para cualquier tipo de VPH y tipos oncogénicos, no oncogénicos y específicos, con intervalos de confianza al 95% (IC95%). Se utilizó regresión logística múltiple paso-a-paso para identificar determinantes asociados con la infección. RESULTADOS: La prevalencia total de VPH fue 50.0% (IC95% 48.8,51.3) y por tipos oncogénicos fue 33.8% (IC95% 32.6,35.0). El VPH-16 fue el tipo más prevalente (8.3%, IC95% 7.6,9.0). Los determinantes asociados con un alto riesgo de infección prevalente por VPH oncogénicos fueron no estar casada/unión libre, >1 compañero sexual, infección concomitante por Chlamydia trachomatis, y entre aquéllas con un único compañero sexual en su vida, un compañero con antecedente de múltiples compañeras sexuales. Conclusión. Se confirma la asociación de las infecciones por VPH oncogénicos con el comportamiento sexual de la mujer y se destacan los comportamientos del compañero sexual.

7.
Popul Health Manag ; 26(5): 275-282, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37677001

RESUMO

The United States is facing a maternal health crisis with increasing rates of severe maternal morbidity and mortality. To improve maternal health and promote health equity, the authors developed a novel 2-generation model of postpartum and pediatric care. This article describes the Two-Generation Clinic (Two-Gen) and model of care. The model combines a dyadic strategy for simultaneous maternal and pediatric care with the collaborative care model in which seamless primary and behavioral health care are delivered to address the physical health, behavioral health, and social service needs of families. The transdisciplinary team includes primary care physicians, nurse practitioners, psychiatrists, obstetrician-gynecologists, social workers, care navigators, and lactation specialists. Dyad clinic visits are coscheduled (at the same time) and colocated (in the same examination room) with the same primary care provider. In the Two-Gen, the majority (89%) of the mothers self-identify as racial and ethnic minorities. More than 40% have a mental health diagnosis. Almost all mothers (97.8%) completed mental health screenings, >50.0% have received counseling from a social worker, 17.2% had a visit with a psychiatrist, and 50.0% received lactation counseling. Over 80% of the children were up to date with their well-child visits and immunizations. The Two-Gen is a promising model of care that has the potential to inform the design of postpartum care models and promote health equity in communities with the highest maternal health disparities.

8.
Microbiol Spectr ; 11(4): e0506322, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37347184

RESUMO

Several studies have described the contribution of glutamate-transforming microbiota to the development of chronic ailments. For instance, the blood concentration of glutamate is higher in some patients with fibromyalgia, chronic fatigue, and pain. Taking advantage of a naturally occurring strain of Bifidobacterium that is able to transform glutamate in γ-aminobutyric caid (GABA), B. adolescentis IPLA60004, we designed a placebo-controlled intervention to test if the presence of this GABA-producing bifidobacteria in mice was able to impact the concentration of glutamate in the blood in comparison with the administration of other strain of the same species lacking the genes of the glutamate decarboxylase (gad) cluster. Animals were fed every day with 8 log CFU of bacteria in a sterilized milk vehicle for 14 days. Samples from feces and blood were collected during this period, and afterwards animals were sacrificed, tissues were taken from different organs, and the levels of different metabolites were analyzed by ultrahigh-performance liquid chromatography coupled to mass spectrometry. The results showed that both bacterial strains orally administered survived in the fecal content, and animals fed B. adolescentis IPLA60004 showed a significant reduction of their glutamate serum concentration, while a nonsignificant decrease was observed for animals fed a reference strain, B. adolescentis LGM10502. The variations observed in GABA were influenced by the gender of the animals, and no significant changes were observed in different tissues of the brain. These results suggest that orally administered GABA-producing probiotics could reduce the glutamate concentration in blood, opening a case for a clinical trial study in chronic disease patients. IMPORTANCE This work presents the results of a trial using mice as a model that were fed with a bacterial strain of the species B. adolescentis, which possesses different active genes capable of degrading glutamate and converting it into GABA. Indeed, the bacterium is able to survive the passage through the gastric tract and, more importantly, the animals reduce over time the concentration of glutamate in their blood. The importance of this result lies in the fact that several chronic ailments, such as fibromyalgia, are characterized by an increase in glutamate. Our results indicate that an oral diet with this probiotic-type bacteria could reduce the concentration of glutamate and, therefore, reduce the symptoms associated with the excess of this neurotransmitter.


Assuntos
Bifidobacterium adolescentis , Fibromialgia , Probióticos , Camundongos , Animais , Bifidobacterium adolescentis/metabolismo , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Bifidobacterium/genética , Bifidobacterium/metabolismo , Fezes/microbiologia , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/metabolismo
9.
J Nephrol ; 36(5): 1383-1393, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37253904

RESUMO

BACKGROUND: In recent years, chronic kidney disease has increased in the pediatric population and has been related to environmental factors. In the diagnosis of kidney damage, in addition to the traditional parameters, early kidney damage biomarkers, such as kidney injury molecule 1, cystatin C, and osteopontin, among others, have been implemented as predictors of early pathological processes. OBJECTIVE: This study aimed to evaluate the relationship between exposure to environmental pollutants and early kidney damage biomarkers. METHODS: A cross-sectional pilot study was conducted in February 2016 and involved 115 apparently healthy children aged 6-15 residing in Apizaco, Tlaxcala. Participant selection was carried out randomly from among 16,472 children from the municipality of Apizaco. A socio-demographic questionnaire included  age, sex, education, duration of residence in the area, occupation, water consumption and dietary habits, pathological history, and some non-specific symptoms. Physical examination included blood pressure, weight, and height. The urine concentrations of urinary aluminum, total arsenic, boron, calcium, chromium, copper, mercury, potassium, sodium, magnesium, manganese, molybdenum, lead, selenium, silicon, thallium, vanadium, uranium, and zinc, were measured. Four of the 115 participants selected for the study were excluded due to an incomplete questionnaire or lack of a medical examination, leaving a final sample population of 111 participants. RESULTS: The results showed a mean estimated glomerular filtration rate of 89.1 ± 9.98 mL/min/1.73m2 and a mean albumin/creatinine ratio of 12.9 ± 16.7 mg/g urinary creatinine. We observed a positive and significant correlation between estimated glomerular filtration rate with fluoride, total arsenic and lead, and a correlation of albumin/creatinine ratio with fluoride, vanadium, and total arsenic. There was also a significant correlation between the early kidney damage biomarkers and fluoride, vanadium, and total arsenic, except for cystatin C. CONCLUSION: In conclusion, our results show that four urinary biomarkers: α1-microglobulin, cystatin C, kidney injury molecule 1, and neutrophil gelatinase-associated lipocalin are related to environmental exposure to urinary fluoride, vanadium, and total arsenic in our pediatric population.


Assuntos
Arsênio , Insuficiência Renal Crônica , Humanos , Criança , Arsênio/efeitos adversos , Arsênio/análise , Cistatina C , Fluoretos , Vanádio , México/epidemiologia , Estudos Transversais , Creatinina , Projetos Piloto , Rim , Biomarcadores , Albuminas , Taxa de Filtração Glomerular , Lipocalina-2
10.
Pain Manag Nurs ; 23(6): 871-877, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35491350

RESUMO

BACKGROUND: All nurses should receive training and education regarding pain as part of their pre-graduate stage, as its assessment and appropriate management when treating patients largely depends on them. With the right knowledge it is possible to reduce its high prevalence, as well as the serious consequences it can lead to. AIM: To determine the level of knowledge and attitudes towards pain of final-year nursing students in Spain. METHODS: Descriptive cross-sectional study using a convenience sample of five Spanish universities during the academic year 2020-2021. The Spanish version of the Knowledge and Attitudes Survey Regarding Pain (KASRP) was used. In addition, socio-demographic variables such as age, sex, relationship status, employment status, and the number of dependants were collected. The specific palliative or oncology subjects of each university was also assessed. RESULTS: A total of 224 questionnaires were collected. One of the nursing universities obtained the best score in the KASRP (59.75%) which was significant (p = .001). This university was the only one that offers specific subjects in palliative or oncologic care. A training deficit in aspects related to pain assessment and pharmacologic concepts was detected. We found no relationship between the KASRP and the different sociodemographic variables. CONCLUSIONS: Specific training in palliative care improves the students' knowledge regarding pain, although the results did not reach an acceptable minimum. The universities' training programs for Spanish students need to be adapted in order to achieve better results.


Assuntos
Estudantes de Enfermagem , Humanos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Dor , Inquéritos e Questionários
11.
Acta Parasitol ; 67(2): 678-686, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35013941

RESUMO

AIM: This study was designed to investigate if culturing nematophagous fungi (NF) in the presence of a Haemonchus contortus larva crude extract (HcCE) enhances the nematocidal activity of nematophagous fungi liquid culture filtrates (NFCF). MATERIALS AND METHODS: Four NF Arthrobotrys oligospora, A. musiformis, Duddingtonia flagrans and Clonostachys rosea were cultured in flasks (n = 5) containing Czapek-Dox broth medium (CDB) in the presence or absence of HcCE. NFCF recovered by filtration of each fungus (200 mg/mL) were assessed on H. contortus infective larvae (L3) using 96-well micro-titer plates (n = 4). Additionally, CDB and water were considered negative controls, while Ivermectin acted as a positive control. After 48 h confrontation, ten 10-µL aliquots of each well were deposited on slides and observed under the microscope (40 ×). Dead and alive larvae in the aliquots were quantified, and a mortality rate (MR) was estimated. RESULTS: The MR of the different NFCF was greatly enhanced by the presence of HcCE. The four NF incubated in the absence of HcCE showed low mortality percentages from 8.2 to 25.8%; in contrast, when the assessed NF growth in the presence of HcCE showed a lethal activity ranging from 66.8 to 80.5%. Only C. rosea showed a moderate increase in the presence of the elicitor (42.7%). CONCLUSION: This study shows evidence about the HcCE enhances the production of nematocidal activity in NFCF. Future studies should be performed to elucidate the compounds responsible of the nematocidal activity that could have important implications in the control of sheep haemonchosis.


Assuntos
Haemonchus , Nematoides , Trichostrongyloidea , Animais , Antinematódeos/farmacologia , Misturas Complexas , Fezes , Haemonchus/microbiologia , Larva/microbiologia , Controle Biológico de Vetores , Ovinos
12.
Pest Manag Sci ; 78(1): 116-125, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34453401

RESUMO

BACKGROUND: Economic injury level (EIL) and economic threshold (ET) are customary tools for integrated pest management. Cacopsylla pyri L. is a major pest in pear orchards. The aim of this work was to establish EIL and ET for the optimization of the use of insecticides to control this psyllid, considering biocontrol and two spraying strategies (low-toxicity versus broad spectrum chemicals). This research was conducted over 4 years in five commercial pear, cv. Ercolini, orchards in south-eastern Spain. RESULTS: Psyllids and ant populations were followed using periodic sampling, and the russet on fruits was quantified. The effect of spray intensity and ant exclusion on psyllid abundance and yield were also tested: both had a significant effect on the cumulative number of C. pyri (CNP), yield and fruit weight. Yield was found to be negatively correlated with CNP. The russet index (RI) increased in a sigmoidal fashion as a function of CNP, being significantly higher with than without ant exclusion. The commercial categorization of fruits was explained satisfactorily as a function of CNP and the cumulative number of ants (CNA). The quantitative EIL was established at a CNP of 427.2 for spraying with paraffinic oil and 425.7 for abamectin. As for the cosmetic EIL, when CNA was zero, this EIL was 24.2, at a CNP of 16.6 for spraying with paraffinic oil or abamectin. CONCLUSIONS: The use of products of low toxicity, for the conservation of ants, is expected to increase ET and, thus, reduce the intensity of spraying. © 2021 Society of Chemical Industry.


Assuntos
Formigas , Hemípteros , Inseticidas , Pyrus , Animais , Espanha
13.
Front Cell Neurosci ; 15: 668286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262437

RESUMO

Despite advancements in the radiotherapeutic management of brain malignancies, resultant sequelae include persistent cognitive dysfunction in the majority of survivors. Defining the precise causes of normal tissue toxicity has proven challenging, but the use of preclinical rodent models has suggested that reductions in neurogenesis and microvascular integrity, impaired synaptic plasticity, increased inflammation, and alterations in neuronal structure are contributory if not causal. As such, strategies to reverse these persistent radiotherapy-induced neurological disorders represent an unmet medical need. AM251, a cannabinoid receptor 1 reverse agonist known to facilitate adult neurogenesis and synaptic plasticity, may help to ameliorate radiation-induced CNS impairments. To test this hypothesis, three treatment paradigms were used to evaluate the efficacy of AM251 to ameliorate radiation-induced learning and memory deficits along with disruptions in mood at 4 and 12 weeks postirradiation. Results demonstrated that acute (four weekly injections) and chronic (16 weekly injections) AM251 treatments (1 mg/kg) effectively alleviated cognitive and mood dysfunction in cranially irradiated mice. The beneficial effects of AM251 were exemplified by improved hippocampal- and cortical-dependent memory function on the novel object recognition and object in place tasks, while similar benefits on mood were shown by reductions in depressive- and anxiety-like behaviors on the forced swim test and elevated plus maze. The foregoing neurocognitive benefits were associated with significant increases in newly born (doublecortin+) neurons (1.7-fold), hippocampal neurogenesis (BrdU+/NeuN+mature neurons, 2.5-fold), and reduced expression of the inflammatory mediator HMGB (1.2-fold) in the hippocampus of irradiated mice. Collectively, these findings indicate that AM251 ameliorates the effects of clinically relevant cranial irradiation where overall neurological benefits in memory and mood coincided with increased hippocampal cell proliferation, neurogenesis, and reduced expression of proinflammatory markers.

14.
An Acad Bras Cienc ; 93(2): e20190796, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190841

RESUMO

Climate change has already altered global biodiversity, causing the migration of species and changes in habitat distribution. To implement a sustainable conservation strategy, it is necessary to understand the impacts of climate change on species. Lessingianthus is a South American genus that includes numerous endangered species, some of which grow in the Brazilian Cerrado, a Neotropical savanna considered a world's biodiversity hotspot. However, the impact of global climate change on these species has still not been estimated. We evaluate the effect of climate change on the habitat of 10 threatened Lessingianthus species and on their potential distribution, and assess the effectiveness of current protected areas (PAs) using ecological niche models. Based on the maximum entropy algorithm (Maxent), we first modeled the potential distribution of these species under current climatic conditions and then projected the distribution for two future scenarios of climate change (RCP 4.5 and RCP 8.5) and two time periods (2050 and 2070). We predicted current habitat suitability and identified suitable bioclimatic variables for these species. Our findings suggest that the area comprising the south and southeast of Cerrado is irreplaceable and the most biotically stable region for these endangered species; therefore, it should be considered a conservation priority area.


Assuntos
Asteraceae , Mudança Climática , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção
15.
Front Cell Neurosci ; 15: 645240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33708075

RESUMO

Enhanced neuronal activity in the healthy brain can induce de novo myelination and behavioral changes. As neuronal activity can be achieved using non-invasive measures, it may be of interest to utilize the innate ability of neuronal activity to instruct myelination as a novel strategy for myelin repair in demyelinating disorders such as multiple sclerosis (MS). Preclinical studies indicate that stimulation of neuronal activity in demyelinated lesions indeed has the potential to improve remyelination and that the stimulation paradigm is an important determinant of success. However, future studies will need to reveal the most efficient stimulation protocols as well as the biological mechanisms implicated. Nonetheless, clinical studies have already explored non-invasive brain stimulation as an attractive therapeutic approach that ameliorates MS symptomatology. However, whether symptom improvement is due to improved myelin repair remains unclear. In this mini-review, we discuss the neurobiological basis and potential of enhancing neuronal activity as a novel therapeutic approach in MS.

16.
Neurobiol Dis ; 151: 105252, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33418069

RESUMO

Galactic cosmic radiation (GCR), composed of highly energetic and fully ionized atomic nuclei, produces diverse deleterious effects on the body. In researching the neurological risks of GCR exposures, including during human spaceflight, various ground-based single-ion GCR irradiation paradigms induce differential disruptions of cellular activity and overall behavior. However, it remains less clear how irradiation comprising a mix of multiple ions, more accurately recapitulating the space GCR environment, impacts the central nervous system. We therefore examined how mixed-ion GCR irradiation (two similar 5-6 beam combinations of protons, helium, oxygen, silicon and iron ions) influenced neuronal connectivity, functional generation of activity within neural circuits and cognitive behavior in mice. In electrophysiological recordings we find that space-relevant doses of mixed-ion GCR preferentially alter hippocampal inhibitory neurotransmission and produce related disruptions in the local field potentials of hippocampal oscillations. Such underlying perturbation in hippocampal network activity correspond with perturbed learning, memory and anxiety behavior.


Assuntos
Radiação Cósmica/efeitos adversos , Hipocampo/efeitos da radiação , Transmissão Sináptica/efeitos da radiação , Animais , Comportamento Animal/efeitos da radiação , Disfunção Cognitiva/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
17.
Pharmacol Ther ; 218: 107683, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32961265

RESUMO

Since the first descriptions of hepatocyte-released exosome-like vesicles in 2008, the number of publications describing Extracellular Vesicles (EVs) released by liver cells in the context of hepatic physiology and pathology has grown exponentially. This growing interest highlights both the importance that cell-to-cell communication has in the organization of multicellular organisms from a physiological point of view, as well as the opportunity that these circulating organelles offer in diagnostics and therapeutics. In the present review, we summarize systematically and comprehensively the myriad of works that appeared in the last decade and lighted the discussion about the best opportunities for using EVs in liver disease therapeutics.


Assuntos
Vesículas Extracelulares , Gastroenterologia , Comunicação Celular , Sistemas de Liberação de Medicamentos , Exossomos , Vesículas Extracelulares/patologia , Vesículas Extracelulares/fisiologia , Humanos , Hepatopatias/tratamento farmacológico
18.
Methods Mol Biol ; 2191: 135-149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32865743

RESUMO

In just over 10 years, the use of optogenetic technologies in neuroscience has become widespread, having today a tremendous impact on our understanding of brain function. An extensive number of studies have implemented a variety of tools allowing for the manipulation of neurons with light, including light-activated ion channels or G protein-coupled receptors, among other innovations. In this context, the proper calibration of photostimulation in vivo remains crucial to dissect brain circuitry or investigate the effect of neuronal activity on specific subpopulations of neurons and glia. Depending on the scientific question, the design of specific stimulation protocols must consider from the choice of the animal model to the light stimulation pattern to be delivered. In this chapter, we describe a detailed framework to investigate neuron-glia interactions in both mouse pups and adults using an optogenetic approach.


Assuntos
Channelrhodopsins/genética , Neuroglia/metabolismo , Neurônios/metabolismo , Optogenética/métodos , Animais , Encéfalo/metabolismo , Encéfalo/fisiologia , Humanos , Camundongos , Neuroglia/patologia , Neurônios/patologia , Técnicas de Patch-Clamp/métodos , Ratos
19.
Sci Adv ; 6(49)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33277253

RESUMO

Remyelination failure in multiple sclerosis (MS) is associated with a migration/differentiation block of oligodendroglia. The reason for this block is highly debated. It could result from disease-related extrinsic or intrinsic regulators in oligodendroglial biology. To avoid confounding immune-mediated extrinsic effect, we used an immune-deficient mouse model to compare induced pluripotent stem cell-derived oligodendroglia from MS and healthy donors following engraftment in the developing CNS. We show that the MS-progeny behaves and differentiates into oligodendrocytes to the same extent as controls. They generate equal amounts of myelin, with bona fide nodes of Ranvier, and promote equal restoration of their host slow conduction. MS-progeny expressed oligodendrocyte- and astrocyte-specific connexins and established functional connections with donor and host glia. Thus, MS oligodendroglia, regardless of major immune manipulators, are intrinsically capable of myelination and making functional axo-glia/glia-glia connections, reinforcing the view that the MS oligodendrocyte differentiation block is not from major intrinsic oligodendroglial deficits.

20.
Front Behav Neurosci ; 14: 535885, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192361

RESUMO

The radiation fields in space define tangible risks to the health of astronauts, and significant work in rodent models has clearly shown a variety of exposure paradigms to compromise central nervous system (CNS) functionality. Despite our current knowledge, sex differences regarding the risks of space radiation exposure on cognitive function remain poorly understood, which is potentially problematic given that 30% of astronauts are women. While work from us and others have demonstrated pronounced cognitive decrements in male mice exposed to charged particle irradiation, here we show that female mice exhibit significant resistance to adverse neurocognitive effects of space radiation. The present findings indicate that male mice exposed to low doses (≤30 cGy) of energetic (400 MeV/n) helium ions (4He) show significantly higher levels of neuroinflammation and more extensive cognitive deficits than females. Twelve weeks following 4He ion exposure, irradiated male mice demonstrated significant deficits in object and place recognition memory accompanied by activation of microglia, marked upregulation of hippocampal Toll-like receptor 4 (TLR4), and increased expression of the pro-inflammatory marker high mobility group box 1 protein (HMGB1). Additionally, we determined that exposure to 4He ions caused a significant decline in the number of dendritic branch points and total dendritic length along with the hippocampus neurons in female mice. Interestingly, only male mice showed a significant decline of dendritic spine density following irradiation. These data indicate that fundamental differences in inflammatory cascades between male and female mice may drive divergent CNS radiation responses that differentially impact the structural plasticity of neurons and neurocognitive outcomes following cosmic radiation exposure.

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