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1.
Vet Res ; 55(1): 76, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867337

RESUMO

Bovine mastitis remains a major disease in cattle world-wide. In the mammary gland, mammary epithelial cells (MEC) are sentinels equipped with receptors allowing them to detect and respond to the invasion by bacterial pathogens, in particular Escherichia coli. Lipopolysaccharide (LPS) is the major E. coli motif recognized by MEC through its interaction with the TLR4 receptor and the CD14 co-receptor. Previous studies have highlighted the role of soluble CD14 (sCD14) in the efficient recognition of LPS molecules possessing a full-length O-antigen (LPSS). We demonstrate here that MEC are able to secrete CD14 and are likely to contribute to the presence of sCD14 in milk. We then investigated how sCD14 modulates and is required for the response of MEC to LPSS. This study highlights the key role of sCD14 for the full activation of the Myd88-independent pathway by LPSS. We also identified several lncRNA that are activated in MEC in response to LPS, including one lncRNA showing homologies with the mir-99a-let-7c gene (MIR99AHG). Altogether, our results show that a full response to LPS by mammary epithelial cells requires sCD14 and provide detailed information on how milk sCD14 can contribute to an efficient recognition of LPS from coliform pathogens.


Assuntos
Células Epiteliais , Receptores de Lipopolissacarídeos , Lipopolissacarídeos , Glândulas Mamárias Animais , Animais , Receptores de Lipopolissacarídeos/metabolismo , Receptores de Lipopolissacarídeos/genética , Bovinos , Células Epiteliais/metabolismo , Lipopolissacarídeos/farmacologia , Feminino , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/metabolismo , Leite
2.
bioRxiv ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38559143

RESUMO

Sleep is essential for optimal functioning and health. Interconnected to multiple biological, psychological and socio-environmental factors (i.e., biopsychosocial factors), the multidimensional nature of sleep is rarely capitalized on in research. Here, we deployed a data-driven approach to identify sleep-biopsychosocial profiles that linked self-reported sleep patterns to inter-individual variability in health, cognition, and lifestyle factors in 770 healthy young adults. We uncovered five profiles, including two profiles reflecting general psychopathology associated with either reports of general poor sleep or an absence of sleep complaints (i.e., sleep resilience) respectively. The three other profiles were driven by sedative-hypnotics-use and social satisfaction, sleep duration and cognitive performance, and sleep disturbance linked to cognition and mental health. Furthermore, identified sleep-biopsychosocial profiles displayed unique patterns of brain network organization. In particular, somatomotor network connectivity alterations were involved in the relationships between sleep and biopsychosocial factors. These profiles can potentially untangle the interplay between individuals' variability in sleep, health, cognition and lifestyle - equipping research and clinical settings to better support individual's well-being.

3.
Res Sq ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38659875

RESUMO

Sleep is essential for optimal functioning and health. Interconnected to multiple biological, psychological and socio-environmental factors (i.e., biopsychosocial factors), the multidimensional nature of sleep is rarely capitalized on in research. Here, we deployed a data-driven approach to identify sleep-biopsychosocial profiles that linked self-reported sleep patterns to inter-individual variability in health, cognition, and lifestyle factors in 770 healthy young adults. We uncovered five profiles, including two profiles reflecting general psychopathology associated with either reports of general poor sleep or an absence of sleep complaints (i.e., sleep resilience) respectively. The three other profiles were driven by sedative-hypnotics-use and social satisfaction, sleep duration and cognitive performance, and sleep disturbance linked to cognition and mental health. Furthermore, identified sleep-biopsychosocial profiles displayed unique patterns of brain network organization. In particular, somatomotor network connectivity alterations were involved in the relationships between sleep and biopsychosocial factors. These profiles can potentially untangle the interplay between individuals' variability in sleep, health, cognition and lifestyle - equipping research and clinical settings to better support individual's well-being.

4.
Sleep Med ; 115: 21-29, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325157

RESUMO

STUDY OBJECTIVE: To provide a comprehensive assessment of sleep state misperception in insomnia disorder (INS) and good sleepers (GS) by comparing recordings performed for one night in-lab (PSG and night review) and during several nights at-home (actigraphy and sleep diaries). METHODS: Fifty-seven INS and 29 GS wore an actigraphy device and filled a sleep diary for two weeks at-home. They subsequently completed a PSG recording and filled a night review in-lab. Sleep perception index (subjective/objective × 100) of sleep onset latency (SOL), sleep duration (TST) and wake duration (TST) were computed and compared between methods and groups. RESULTS: GS displayed a tendency to overestimate TST and WASO but correctly perceived SOL. The degree of misperception was similar across methods within the GS group. In contrast, INS underestimated their TST and overestimated their SOL both in-lab and at-home, yet the severity of misperception of SOL was larger at-home than in-lab. Finally, INS overestimated WASO only in-lab while correctly perceiving it at-home. While only the degree of TST misperception was stable across methods in INS, misperception of SOL and WASO were dependent on the method used. CONCLUSIONS: We found that GS and INS exhibit opposite patterns and severity of sleep misperception. While the degree of misperception in GS was similar across methods, only sleep duration misperception was reliably detected by both in-lab and at-home methods in INS. Our results highlight that, when assessing sleep misperception in insomnia disorder, the environment and method of data collection should be carefully considered.


Assuntos
Actigrafia , Distúrbios do Início e da Manutenção do Sono , Humanos , Polissonografia/métodos , Actigrafia/métodos , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Sono , Latência do Sono
5.
J Anim Sci Biotechnol ; 14(1): 100, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420291

RESUMO

BACKGROUND: Mammary gland (MG) infections (mastitis) are frequent diseases of dairy cows that affect milk quality, animal welfare and farming profitability. These infections are commonly associated with the bacteria Escherichia coli and Staphylococcus aureus. Different in vitro models have been used to investigate the early response of the MG to bacteria, but the role of the teat in mastitis pathogenesis has received less attention. In this study, we used punch-excised teat tissue as an ex vivo model to study the immune mechanisms that arise early during infection when bacteria have entered the MG. RESULTS: Cytotoxicity and microscopic analyses showed that bovine teat sinus explants have their morphology and viability preserved after 24 h of culture and respond to ex vivo stimulation with TLR-agonists and bacteria. LPS and E. coli trigger stronger inflammatory response in teat when compared to LTA and S. aureus, leading to a higher production of IL-6 and IL-8, as well as to an up-regulation of proinflammatory genes. We also demonstrated that our ex vivo model can be applied to frozen-stored explants. CONCLUSIONS: In compliance with the 3Rs principle (replacement, reduction and refinement) in animal experimentation, ex vivo explant analyses proved to be a simple and affordable approach to study MG immune response to infection. This model, which better reproduces organ complexity than epithelial cell cultures or tissue slices, lends itself particularly well to studying the early phases of the MG immune response to infection.

6.
J Dairy Sci ; 106(6): 4245-4256, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37080786

RESUMO

Bovine mastitis is mainly caused by bacterial infection and is responsible for important economic losses as well as alterations of the health and welfare of animals. The increase in somatic cell count (SCC) in milk during mastitis is mainly due to the influx of neutrophils, which have a crucial role in the elimination of pathogens. For a long time, these first-line defenders have been viewed as microbe killers, with a limited role in the orchestration of the immune response. However, their role is more complex: we recently characterized a bovine neutrophil subset expressing major histocompatibility complex class II (MHC-II) molecules (MHC-IIpos), usually distributed on antigen-presenting cells, as having regulatory capacities in cattle. In this study, our objective was to evaluate the implication of different neutrophils subsets in the mammary gland immunity during clinical and subclinical mastitis. Using flow cytometry, we analyzed the presence of MHC-IIpos neutrophils in blood and in milk during clinical mastitis at different time points of inflammation (n = 10 infected quarters) and during subclinical mastitis, defined as the presence of bacteria and an SCC >150,000 cells/mL (n = 27 infected quarters). Our results show, for the first time, that in blood and milk, neutrophils are a heterogeneous population and encompass at least 2 subsets distinguishable by their expression of MHC-II. In milk without mastitis, we observed higher production of reactive oxygen species and higher phagocytosis capacity of MHC-IIpos neutrophils compared with their MHC-IIneg counterparts, indicating the high bactericidal capacities of MHC-IIpos neutrophils. MHC-IIpos neutrophils are enriched in milk compared with blood during subclinical mastitis but not during clinical mastitis. Moreover, we observed a positive and highly significant correlation between MHC-IIpos neutrophils and T lymphocytes present in milk during subclinical mastitis. Our experiments involved a total of 47 cows (40 Holstein and 7 Normande cows). To conclude, our study opens the way to the discovery of new biomarkers of mastitis inflammation.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Animais , Bovinos , Feminino , Neutrófilos , Leite/microbiologia , Mastite Bovina/microbiologia , Inflamação/veterinária , Complexo Principal de Histocompatibilidade , Contagem de Células/veterinária , Glândulas Mamárias Animais/microbiologia
7.
J Reprod Immunol ; 156: 103826, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36746006

RESUMO

T-lymphocytes are key mediators of adaptive cellular immunity and knowledge about distinct subsets of these cells in healthy and infected mammary gland secretions remains limited. In this study, we used a multiplex cytometry panel to show that staphylococcal mastitis causes the activation of CD4+, CD8+ and γδ T-cells found in bovine milk. We also highlight remarkable differences in the proportions of naïve and memory T-cells subsets found in blood and milk. These observations will contribute to a better understanding of cell-mediated immune mechanisms in the udder and to the development of new therapeutic and preventive strategies targeting mastitis.


Assuntos
Mastite Bovina , Leite , Humanos , Feminino , Animais , Bovinos , Staphylococcus aureus , Subpopulações de Linfócitos T , Diferenciação Celular , Glândulas Mamárias Animais
8.
Front Immunol ; 13: 1031785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341445

RESUMO

The epithelium of the mammary gland (MG) fulfills three major functions: nutrition of progeny, transfer of immunity from mother to newborn, and its own defense against infection. The defense function of the epithelium requires the cooperation of mammary epithelial cells (MECs) with intraepithelial leucocytes, macrophages, DCs, and resident lymphocytes. The MG is characterized by the secretion of a large amount of a nutrient liquid in which certain bacteria can proliferate and reach a considerable bacterial load, which has conditioned how the udder reacts against bacterial invasions. This review presents how the mammary epithelium perceives bacteria, and how it responds to the main bacterial genera associated with mastitis. MECs are able to detect the presence of actively multiplying bacteria in the lumen of the gland: they express pattern recognition receptors (PRRs) that recognize microbe-associated molecular patterns (MAMPs) released by the growing bacteria. Interactions with intraepithelial leucocytes fine-tune MECs responses. Following the onset of inflammation, new interactions are established with lymphocytes and neutrophils recruited from the blood. The mammary epithelium also identifies and responds to antigens, which supposes an antigen-presenting capacity. Its responses can be manipulated with drugs, plant extracts, probiotics, and immune modifiers, in order to increase its defense capacities or reduce the damage related to inflammation. Numerous studies have established that the mammary epithelium is a genuine effector of both innate and adaptive immunity. However, knowledge gaps remain and newly available tools offer the prospect of exciting research to unravel and exploit the multiple capacities of this particular epithelium.


Assuntos
Glândulas Mamárias Animais , Mastite Bovina , Humanos , Feminino , Animais , Recém-Nascido , Bovinos , Epitélio , Ruminantes , Inflamação
9.
Sleep Med ; 97: 13-26, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35691208

RESUMO

STUDY OBJECTIVES: To assess the effects of Cognitive Behavioral Therapy for insomnia (CBTi) on subjective and objective measures of sleep, sleep-state misperception and cognitive performance. METHODS: We performed a randomized-controlled trial with a treatment group and a wait-list control group to assess changes in insomnia symptoms after CBTi (8 weekly group sessions/3 months) in 62 participants with chronic insomnia. To this end, we conducted a multimodal investigation of sleep and cognition including subjective measures of sleep difficulties (Insomnia Severity Index [ISI]; sleep diaries) and cognitive functioning (Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire), objective assessments of sleep (polysomnography recording), cognition (attention and working memory tasks), and sleep-state misperception measures, collected at baseline and at 3-months post-randomization. We also assessed ISI one year after CBTi. Our main analysis investigated changes in sleep and cognition after 3 months (treatment versus wait-list). RESULTS: While insomnia severity decreased and self-reported sleep satisfaction improved after CBTi, we did not find any significant change in objective and subjective sleep measures (e.g., latency, duration). Degree of discrepancy between subjective and objective sleep (i.e., sleep misperception) in sleep latency and sleep duration decreased after CBTi suggesting a better perception of sleep after CBTi. In contrast, both objective and subjective cognitive functioning did not improve after CBTi. CONCLUSIONS: We showed that group-CBTi has a beneficial effect on variables pertaining to the subjective perception of sleep, which is a central feature of insomnia. However, we observed no effect of CBTi on measures of cognitive functioning.


Assuntos
Terapia Cognitivo-Comportamental , Distúrbios do Início e da Manutenção do Sono , Cognição , Humanos , Sono , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
10.
Front Vet Sci ; 9: 891893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754538

RESUMO

Dendritic cells are sentinels of the immune system responsible for the initiation of adaptive immune mechanisms. In that respect, the study of these cells is essential for a full understanding of host response to infectious agents and vaccines. In ruminants, the large blood volume facilitates the isolation of abundant monocytes and their derivation to other antigen-presenting cells such as dendritic cells and macrophages. However, the available protocols for the production of bovine monocyte-derived dendritic cells (moDCs) rely mostly on time-consuming and costly techniques such as density gradient centrifugation and magnetic sorting of cells. In this study, we describe a simplified protocol for the production of bovine moDC using conventional and serum-free media. We also employ moDC produced by this approach to carry out a flow cytometry-based antigen presentation assay adapted to blood fresh or frozen cells. The experimental strategies described here might enable the setup of studies involving a large number of individuals, requiring a large number of dendritic cells, or relying on the utilization of cryopreserved blood cells. These simplified protocols might contribute to the elucidation of cell-mediated immune responses in bovine.

11.
Vaccines (Basel) ; 10(2)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35214754

RESUMO

Mastitis is a major problem in dairy farming. Vaccine prevention of mammary bacterial infections is of particular interest in helping to deal with this issue, all the more so as antibacterial drug inputs in dairy farms must be reduced. Unfortunately, the effectiveness of current vaccines is not satisfactory. In this review, we examine the possible reasons for the current shortcomings of mastitis vaccines. Some reasons stem from the peculiarities of the mammary gland immunobiology, others from the pathogens adapted to the mammary gland niche. Infection does not induce sterilizing protection, and recurrence is common. Efficacious vaccines will have to elicit immune mechanisms different from and more effective than those induced by infection. We propose focusing our research on a few points pertaining to either the current immune knowledge or vaccinology approaches to get out of the current deadlock. A possible solution is to focus on the contribution of cell-mediated immunity to udder protection based on the interactions of T cells with the mammary epithelium. On the vaccinology side, studies on the orientation of the immune response by adjuvants, the route of vaccine administration and the delivery systems are among the keys to success.

12.
AIDS Res Hum Retroviruses ; 38(1): 64-72, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030452

RESUMO

Emergence of drug resistance demands new therapeutic strategies against the human immunodeficiency virus (HIV). Currently, there is an increasing research focus on targeting gene expression-the crucial step wherein new viruses and new viral strains are amplified. Moreover, natural products are also being considered as potential candidates for new antivirals. We screened the extract obtained from a Philippine medicinal plant, Mentha cordifolia (Mc). In this study, we demonstrated that Mc ammonium sulfate extract has antiretroviral activity against HIV. HIV-1 latently infected cells (OM10.1) were pretreated with Mc extract and activated with TNFα. In treated cells, viral replication was inhibited in both cell culture supernatant and whole cell lysates. The level of viral production, as measured by the viral p24 protein concentration, was very much inhibited under noncytotoxic concentrations to the similar level without addition of TNFα. Luciferase assays, however, showed that Mc does not inhibit the HIV-1 long terminal repeat-driven gene expression. IκBα degradation and p65 nuclear translocation was also not affected as visualized through Western blot and immunofluorescence. These observations demonstrated that Mc possessed an antiviral component against HIV-1 and warrant further work to explore its target of action at a later step of gene expression. Our study introduces a potential source of a lead compound that targets steps in the HIV life cycle.


Assuntos
Infecções por HIV , HIV-1 , Mentha , Antivirais/farmacologia , Linhagem Celular , Humanos , Extratos Vegetais/farmacologia , Replicação Viral
13.
Integr Environ Assess Manag ; 18(4): 1056-1071, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34436827

RESUMO

A high proportion of populations in most developing countries live below the poverty line and those near refuse grounds resort to dumpsite farming to grow food. Consequently, high levels of waste-derived contaminants are found in crops consumed by these people. This study investigates the extent to which crops cultivated on the Mbale dumpsite (Uganda) were contaminated by 11 metals and 2 non-metals: iron (Fe), aluminum (Al), zinc (Zn), manganese (Mn), copper (Cu), mercury (Hg), lead (Pb), nickel (Ni), cobalt (Co), cadmium (Cd), selenium (Se), chromium (Cr), and arsenic (As). We investigated how element bioaccumulation in crops was influenced by the growth period (short- and long-term crop maturity). The short-term crops were Zea mays and Amaranthus cruentus, whereas the long-term crops were Manihot esculenta, Colocasia esculenta, Musa acuminata, Carica papaya, Coffea arabica, and Saccharum officinarum. Results showed that nine metals were present at concentrations above World Health Organization/Food and Agriculture Organization (WHO/FAO) food safety recommendations and hence may pose health risks to consumers. In this study, leaves contained higher metal concentrations than other analyzed consumable parts. Pb and Co were found at higher concentrations in leaves of short-term crops than in long-term crops. Among short-term crops, only Z. mays seeds contained permissible metal concentrations by WHO/FAO standards. The growth period was also found to influence metal bioaccumulation in crop types. Pb, Co, Fe, Al, and Cu concentrations were significantly higher in the short-term crops than in long-term crops, while Mn, Ni, and Cr concentrations were higher in long-term crops than in short-term crops. Overall, public awareness about the health risks associated with consuming short-term leafy crops grown on dumpsites should be improved to reduce toxic metal exposure. While implementing such a campaign, the food supply of individuals whose survival depends on such crops should not be jeopardized. Therefore, farmers need alternative farming areas outside dumpsites. Integr Environ Assess Manag 2022;18:1056-1071. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Metais Pesados , Poluentes do Solo , Bioacumulação , Produtos Agrícolas , Monitoramento Ambiental/métodos , Humanos , Chumbo , Metais Pesados/análise , Poluentes do Solo/análise , Uganda
14.
PLoS Biol ; 19(11): e3001232, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34735431

RESUMO

Sleep deprivation (SD) leads to impairments in cognitive function. Here, we tested the hypothesis that cognitive changes in the sleep-deprived brain can be explained by information processing within and between large-scale cortical networks. We acquired functional magnetic resonance imaging (fMRI) scans of 20 healthy volunteers during attention and executive tasks following a regular night of sleep, a night of SD, and a recovery nap containing nonrapid eye movement (NREM) sleep. Overall, SD was associated with increased cortex-wide functional integration, driven by a rise of integration within cortical networks. The ratio of within versus between network integration in the cortex increased further in the recovery nap, suggesting that prolonged wakefulness drives the cortex towards a state resembling sleep. This balance of integration and segregation in the sleep-deprived state was tightly associated with deficits in cognitive performance. This was a distinct and better marker of cognitive impairment than conventional indicators of homeostatic sleep pressure, as well as the pronounced thalamocortical connectivity changes that occurs towards falling asleep. Importantly, restoration of the balance between segregation and integration of cortical activity was also related to performance recovery after the nap, demonstrating a bidirectional effect. These results demonstrate that intra- and interindividual differences in cortical network integration and segregation during task performance may play a critical role in vulnerability to cognitive impairment in the sleep-deprived state.


Assuntos
Biomarcadores/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Privação do Sono/fisiopatologia , Comportamento , Córtex Cerebral/fisiopatologia , Análise por Conglomerados , Estado de Consciência , Feminino , Humanos , Masculino , Rede Nervosa/fisiopatologia , Vigília/fisiologia , Adulto Jovem
15.
J Dairy Sci ; 104(10): 10427-10448, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34218921

RESUMO

Infections of the mammary gland remain a frequent disease of dairy ruminants that negatively affect animal welfare, milk quality, farmer serenity, and farming profitability and cause an increase in use of antimicrobials. There is a need for efficacious vaccines to alleviate the burden of mastitis in dairy farming, but this need has not been satisfactorily fulfilled despite decades of research. A careful appraisal of past and current research on mastitis vaccines reveals the peculiarities but also the commonalities among mammary gland infections associated with the major mastitis pathogens Escherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, or Streptococcus dysgalactiae. A major pitfall is that the immune mechanisms of effective protection have not been fully identified. Until now, vaccine development has been directed toward the generation of antibodies. In this review, we drew up an inventory of the main approaches used to design vaccines that aim at the major pathogens for the mammary gland, and we critically appraised the current and tentative vaccines. In particular, we sought to relate efficacy to vaccine-induced defense mechanisms to shed light on some possible reasons for current vaccine shortcomings. Based on the lessons learned from past attempts and the recent results of current research, the design of effective vaccines may take a new turn in the years to come.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Mastite , Infecções Estreptocócicas , Vacinas , Animais , Bovinos , Feminino , Glândulas Mamárias Animais , Mastite/veterinária , Mastite Bovina/prevenção & controle , Infecções Estreptocócicas/prevenção & controle , Infecções Estreptocócicas/veterinária , Streptococcus
16.
J Vis Exp ; (171)2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34096913

RESUMO

Protein purification is imperative to the study of protein structure and function and is usually used in combination with biophysical techniques. It is also a key component in the development of new therapeutics. The evolving era of functional proteomics is fueling the demand for high-throughput protein purification and improved techniques to facilitate this. It was hypothesized that a multi column plate adaptor (MCPA) can interface multiple chromatography columns of different resins with multi-well plates for parallel purification. This method offers an economical and versatile method of protein purification that can be used under gravity or vacuum, rivaling the speed of an automated system. The MCPA can be used to recover milligram yields of protein by an affordable and time efficient method for subsequent characterization and analysis. The MCPA has been used for high-throughput affinity purification of SH3 domains. Ion exchange has also been demonstrated via the MCPA to purify protein post Ni-NTA affinity chromatography, indicating how this system can be adapted to other purification types. Due to its setup with multiple columns, individual customization of parameters can be made in the same purification, unachievable by the current plate-based methods.


Assuntos
Proteínas , Proteômica , Cromatografia de Afinidade/métodos , Proteínas/isolamento & purificação , Proteômica/métodos , Vácuo
17.
Hum Brain Mapp ; 42(12): 3993-4021, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34101939

RESUMO

Simultaneous recording of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) is a very promising non-invasive neuroimaging technique. However, EEG data obtained from the simultaneous EEG-fMRI are strongly influenced by MRI-related artefacts, namely gradient artefacts (GA) and ballistocardiogram (BCG) artefacts. When compared to the GA correction, the BCG correction is more challenging to remove due to its inherent variabilities and dynamic changes over time. The standard BCG correction (i.e., average artefact subtraction [AAS]), require detecting cardiac pulses from simultaneous electrocardiography (ECG) recording. However, ECG signals are also distorted and will become problematic for detecting reliable cardiac peaks. In this study, we focused on a beamforming spatial filtering technique to attenuate all unwanted source activities outside of the brain. Specifically, we applied the beamforming technique to attenuate the BCG artefact in EEG-fMRI, and also to recover meaningful task-based neural signals during an attentional network task (ANT) which required participants to identify visual cues and respond accurately. We analysed EEG-fMRI data in 20 healthy participants during the ANT, and compared four different BCG corrections (non-BCG corrected, AAS BCG corrected, beamforming + AAS BCG corrected, beamforming BCG corrected). We demonstrated that the beamforming approach did not only significantly reduce the BCG artefacts, but also significantly recovered the expected task-based brain activity when compared to the standard AAS correction. This data-driven beamforming technique appears promising especially for longer data acquisition of sleep and resting EEG-fMRI. Our findings extend previous work regarding the recovery of meaningful EEG signals by an optimized suppression of MRI-related artefacts.


Assuntos
Balistocardiografia/normas , Eletroencefalografia/normas , Neuroimagem Funcional/normas , Imageamento por Ressonância Magnética/normas , Adulto , Artefatos , Balistocardiografia/métodos , Eletroencefalografia/métodos , Feminino , Neuroimagem Funcional/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
18.
Kobe J Med Sci ; 67(3): E98-E111, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35367996

RESUMO

In this study, we investigated the antiviral activity of lyophilized crude leaf extracts of the Philippine marshmint (Mentha arvensis L., commonly called yerba buena) against DENV-2 in vitro. The plant specimen was authenticated by DNA barcoding analysis using standard primers for amplification of rbcL, matK, ITS1, ITS2 and trnH-psbA. Aqueous, methanol and ethanol leaf extracts were prepared, and lyophilized prior to testing for its cytotoxicity and antiviral activities. All extracts presented cytotoxic activities against Vero cells in a dose-dependent manner. Half maximal cytotoxicity concentration (CC50) was calculated at 2,889.60 µg/mL for the aqueous extract, 1,928.62 µg/mL for the methanol extract, and 3,380.30 µg/mL for the ethanol extract. Antiviral activities assessed by plaque reduction assay revealed reduced DENV-2 viral infectivity, with the ethanol extract observed to have the strongest activity decreasing plaque numbers by 62% relative to the control. The methanol extract was observed to be most effective when added before infection causing 72% reduction in plaque numbers, whereas none of the extracts inhibited plaque formation by more than 40% when added after infection. DENV-2 NS1 antigen production was significantly reduced by the methanol extract, while viral RNA levels were also decreased as determined by real time RT-PCR. Phytochemical analysis revealed the presence of flavonoids, phenolics, tannins, proteins, reducing sugars and saponins. Our preliminary results are promising, however, it should be interpreted with caution as further studies are needed to establish its potential therapeutic application against dengue infection.


Assuntos
Vírus da Dengue , Mentha , Animais , Antivirais/farmacologia , Chlorocebus aethiops , Filipinas , Extratos Vegetais/farmacologia , Sorogrupo , Células Vero
19.
Neuroimage ; 226: 117547, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33186718

RESUMO

Sleep deprivation leads to significant impairments in cognitive performance and changes to the interactions between large scale cortical networks, yet the hierarchical organization of cortical activity across states is still being explored. We used functional magnetic resonance imaging to assess activations and connectivity during cognitive tasks in 20 healthy young adults, during three states: (i) following a normal night of sleep, (ii) following 24hr of total sleep deprivation, and (iii) after a morning recovery nap. Situating cortical activity during cognitive tasks along hierarchical organizing gradients based upon similarity of functional connectivity patterns, we found that regional variations in task-activations were captured by an axis differentiating areas involved in executive control from default mode regions and paralimbic cortex. After global signal regression, the range of functional differentiation along this axis at baseline was significantly related to decline in working memory performance (2-back task) following sleep deprivation, as well as the extent of recovery in performance following a nap. The relative positions of cortical regions within gradients did not significantly change across states, except for a lesser differentiation of the visual system and increased coupling of the posterior cingulate cortex with executive control areas after sleep deprivation. This was despite a widespread increase in the magnitude of functional connectivity across the cortex following sleep deprivation. Cortical gradients of functional differentiation thus appear relatively insensitive to state-dependent changes following sleep deprivation and recovery, suggesting that there are no large-scale changes in cortical functional organization across vigilance states. Certain features of particular gradient axes may be informative for the extent of decline in performance on more complex tasks following sleep deprivation, and could be beneficial over traditional voxel- or parcel-based approaches in identifying realtionships between state-dependent brain activity and behavior.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Privação do Sono/diagnóstico por imagem , Vigília/fisiologia , Adolescente , Adulto , Encéfalo/fisiopatologia , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Privação do Sono/fisiopatologia , Privação do Sono/psicologia , Adulto Jovem
20.
Vet Res ; 51(1): 129, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059767

RESUMO

Type 3 immunity encompasses innate and adaptive immune responses mediated by cells that produce the signature cytokines IL-17A and IL-17F. This class of effector immunity is particularly adept at controlling infections by pyogenic extracellular bacteria at epithelial barriers. Since mastitis results from infections by bacteria such as streptococci, staphylococci and coliform bacteria that cause neutrophilic inflammation, type 3 immunity can be expected to be mobilized at the mammary gland. In effect, the main defenses of this organ are provided by epithelial cells and neutrophils, which are the main terminal effectors of type 3 immunity. In addition to theoretical grounds, there is observational and experimental evidence that supports a role for type 3 immunity in the mammary gland, such as the production of IL-17A, IL-17F, and IL-22 in milk and mammary tissue during infection, although their respective sources remain to be fully identified. Moreover, mouse mastitis models have shown a positive effect of IL-17A on the course of mastitis. A lot remains to be uncovered before we can safely harness type 3 immunity to reinforce mammary gland defenses through innate immune training or vaccination. However, this is a promising way to find new means of improving mammary gland defenses against infection.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Interleucina-17/imunologia , Mamíferos/imunologia , Glândulas Mamárias Animais/imunologia , Animais , Feminino
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