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1.
J Cell Sci ; 135(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35129196

RESUMO

Recent advances have revealed common pathological changes in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis with related frontotemporal dementia (ALS/FTD). Many of these changes can be linked to alterations in endoplasmic reticulum (ER)-mitochondria signaling, including dysregulation of Ca2+ signaling, autophagy, lipid metabolism, ATP production, axonal transport, ER stress responses and synaptic dysfunction. ER-mitochondria signaling involves specialized regions of ER, called mitochondria-associated membranes (MAMs). Owing to their role in neurodegenerative processes, MAMs have gained attention as they appear to be associated with all the major neurodegenerative diseases. Furthermore, their specific role within neuronal maintenance is being revealed as mutant genes linked to major neurodegenerative diseases have been associated with damage to these specialized contacts. Several studies have now demonstrated that these specialized contacts regulate neuronal health and synaptic transmission, and that MAMs are damaged in patients with neurodegenerative diseases. This Review will focus on the role of MAMs and ER-mitochondria signaling within neurons and how damage of the ER-mitochondria axis leads to a disruption of vital processes causing eventual neurodegeneration.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/metabolismo , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Demência Frontotemporal/metabolismo , Humanos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo
2.
Telemed J E Health ; 30(4): 1006-1012, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37935031

RESUMO

Introduction: Almost half of veterans (44.6%) seen in the U.S. Department of Veterans Affairs outpatient setting are diagnosed with hypertension (HTN). Because of the widespread nature of HTN, use of virtual visits has the potential to improve blood pressure (BP) management. This evaluation assessed the effectiveness of video blood pressure visits (VBPVs) in the management of HTN in veterans enrolled in Veterans Health Administration primary care. Methods: The program was implemented within the existing veteran-centered medical home. VBPVs are scheduled where the nurse observes veterans taking their BP and provides teaching or counseling. A national training curriculum was delivered to local nurse champions through Microsoft Teams. We analyzed improvement in BP over a 2-year period. We also captured actions taken by nurses during the VBPV by searching the electronic notes. Ratings of training and comments were summarized using feedback forms completed after training. Results: In total, 81,476 veterans participated in VBPVs over 2 years. Of those, 44,682 veterans had an existing ICD-10 code related to HTN. Of the 18,078 veterans who had a pre- and post-VBPV BP, the average change to systolic measurement was -10.6 mm Hg (range -82 to 78). Average change to diastolic measurement was -4.61 mm Hg (range -59 to 55). Most interventions addressed medication management (77%). Nurses' evaluations of the program were positive. Conclusions: Video visits provide reliable and convenient veteran-centered care. Such visits enable care when unanticipated interruptions occur such as the coronavirus disease 2019 pandemic. In addition to medication management, nurse-led interventions such as counseling on lifestyle changes can be effective in HTN management.


Assuntos
COVID-19 , Hipertensão , Veteranos , Humanos , Pressão Sanguínea , Saúde dos Veteranos , Hipertensão/tratamento farmacológico , Assistência Centrada no Paciente , COVID-19/epidemiologia
3.
J Sci Food Agric ; 104(5): 3013-3026, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38053417

RESUMO

BACKGROUND: Consumers are seeking healthier alternatives to traditional confectioneries. They value the use of sugar replacers, more natural ingredients and/or environmentally friendly preservation technologies. UV-C light is considered an emerging alternative to thermal pasteurization that leaves no residue and requires minimal energy. The present study aimed to investigate the effect of novel sweetener combinations and juice UV-C assisted by mild heat treatment (UV-C/H) on the physicochemical, microbiological, morphological, rheological and sensory properties of orange juice pectin-based confectioneries stored at 5 ± 1 °C for 35 days. RESULTS: For orange juice processing, UV-C/H (pilot-scale Dean-flow reactor; 892 mJ cm-2 ; 50 ± 1 °C) and thermal (T-coil, 80 °C; 6 min) treatments were used. Low-calorie confectionery gels were elaborated using the treated juices, low-methoxyl pectin and various sweetener combinations. UV-C/H and T-coil effectively inactivated juice native microbiota. The proposed formulations, derived from a previous Box-Behnken optimization study, included partial (F1: 3%-sucrose-S + 0.019%-rebaudioside-A-RA) or complete sucrose replacement (F2: 5.5%-erythritol-E + 0.019%-RA), and one control (C:10%-S). In general, the microbiota of the gels prepared with the UV-C/H or T-coil treated juices did not recover during storage. The physicochemical and mechanical parameters of the formulations were significantly influenced by the choice of sweetener and the duration of storage. The gel surface got smoother and had fewer holes when the sucrose level dropped, according to a scanning electron microscopy study. The UV-C/H-treated samples did not differ in acceptability, whereas the measured sensory attributes approached ideal levels. F1 and F2 showed distinctive temporal-dominance-of-sensations profiles, mainly dominated by sweetness and orange taste, respectively. However, consumers perceived sourness and astringency in C during consumption. CONCLUSION: The present study provides significant evidence in support of the development of confectionery gels F1 and F2 made from fruit juice treated by UV-C light assisted by mild heat and combinations of sucrose-alternative sweeteners. In terms of the properties investigated, these confectionery gels were comparable to, or even outperformed the full-sucrose option. © 2023 Society of Chemical Industry.


Assuntos
Citrus sinensis , Edulcorantes , Edulcorantes/análise , Sucos de Frutas e Vegetais , Pectinas , Paladar , Sacarose , Géis
4.
Biochem J ; 477(23): 4491-4513, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33146386

RESUMO

Poly(ADP-ribose) polymerase 1 (PARP-1) is a nuclear enzyme that catalyze the transfer of ADP-ribose units from NAD+ to several target proteins involved in cellular stress responses. Using WRL68 (HeLa derivate) cells, we previously showed that PARP-1 activation induced by oxidative stress after H2O2 treatment lead to depletion of cellular NAD+ and ATP, which promoted cell death. In this work, LC-MS/MS-based phosphoproteomics in WRL68 cells showed that the oxidative damage induced by H2O2 increased the phosphorylation of YAP1, a transcriptional co-activator involved in cell survival, and modified the phosphorylation of other proteins involved in transcription. Genetic or pharmacological inhibition of PARP-1 in H2O2-treated cells reduced YAP1 phosphorylation and degradation and increased cell viability. YAP1 silencing abrogated the protective effect of PARP-1 inhibition, indicating that YAP1 is important for the survival of WRL68 cells exposed to oxidative damage. Supplementation of NAD+ also reduced YAP1 phosphorylation, suggesting that the loss of cellular NAD+ caused by PARP-1 activation after oxidative treatment is responsible for the phosphorylation of YAP1. Finally, PARP-1 silencing after oxidative treatment diminished the activation of the metabolic sensor AMPK. Since NAD+ supplementation reduced the phosphorylation of some AMPK substrates, we hypothesized that the loss of cellular NAD+ after PARP-1 activation may induce an energy stress that activates AMPK. In summary, we showed a new crucial role of PARP-1 in the response to oxidative stress in which PARP-1 activation reduced cell viability by promoting the phosphorylation and degradation of YAP1 through a mechanism that involves the depletion of NAD+.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Estresse Oxidativo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , NAD/genética , NAD/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Poli(ADP-Ribose) Polimerase-1/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
5.
J Food Sci Technol ; 58(4): 1574-1584, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33746284

RESUMO

The drying process used to obtain active food additives is critical to ensure its functionality. In this study, freeze- and spray-drying techniques were evaluated for encapsulation of extracts with antioxidant activity from yerba mate (Ilex paraguariensis), using maltodextrin (MD) as wall material. Additionally, the oxidative stability in a real food matrix (mayonnaise) was assessed. Both MD addition and drying methods affected the physical properties [moisture content, water activity (aW)] and oxidative stability. MD addition diminished moisture content and prevented polyphenol compounds from degradation. The spray-dried powders displayed the lowest moisture content (1.6 ± 0.3% bs), the highest polyphenol content (135.4 mg GAE/g pure extract), and oxidative stability than the freeze-dried samples. The antioxidant capacity of the encapsulated powder subjected to spray-drying increased the oxidative stability of the mayonnaise (258 ± 32 min) more than the other assayed system (165 ± 5 min). Therefore, a natural spray-dried antioxidant food additive was obtained with potential use in the food industry.

6.
Exp Eye Res ; 188: 107790, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31494107

RESUMO

Oxidative stress (OxS) is involved in the development of cell injures occurring in retinal diseases while Poly(ADP-ribose) Polymerase-1 (PARP-1) is a key protein involved in the repair of the DNA damage caused by OxS. Inhibition of PARP-1 activity with the pharmacological inhibitor PJ34 in mouse retinal explants subjected to H2O2-induced oxidative damage resulted in an increase of apoptotic cells. Reduction of cell growth was also observed in the mouse cone like cell line 661 W in the presence of PJ34 under OxS conditions. Mass spectrometry-based phosphoproteomics analysis performed in 661 W cells determined that OxS induced significant changes in the phosphorylation in 1807 of the 8131 peptides initially detected. Blockade of PARP-1 activity after the oxidative treatment additionally increased the phosphorylation of multiple proteins, many of them at SQ motifs and related to the DNA-damage response (DDR). These motifs are substrates of the kinases ATM/ATR, which play a central role in DDR. Western blot analysis confirmed that the ATM/ATR activity measured and the phosphorylation at SQ motifs of ATM/ATR substrates was augmented when PARP-1 activity was inhibited under OxS conditions, in 661 W cells. Phosphorylation of ATM/ATR substrates, including the phosphorylation of the histone H2AX were also induced in organotypic cultures of retinal explants subjected to PARP-1 inhibition during exposure to OxS. In conclusion, inhibition of PARP-1 increased the phosphorylation and hence the activation of several proteins involved in the response to DNA damage, like the ATM protein kinase. This finally resulted in an augmented injury in mouse retinal cells suffering from OxS. Therefore, the inhibition of PARP-1 activity may have a negative outcome in the treatment of retinal diseases in which OxS is involved.


Assuntos
Dano ao DNA , Proteínas do Olho/metabolismo , Estresse Oxidativo , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Retina/patologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Western Blotting , Caspase 3/metabolismo , Morte Celular , Linhagem Celular , Proteínas de Ligação a DNA , Eletroforese em Gel de Poliacrilamida , Histonas/metabolismo , Peróxido de Hidrogênio/toxicidade , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C57BL , Oxidantes/toxicidade , Fenantrenos/farmacologia , Fosfoproteínas/metabolismo , Fosforilação , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Retina/metabolismo
7.
Food Microbiol ; 73: 1-10, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29526194

RESUMO

The aim of this study was to analyze the effectiveness of UV-C light (0-10.6 kJ/m2) assisted by mild heat treatment (50 °C) on the inactivation of Saccharomyces cerevisiae KE 162 in peptone water and fresh carrot-orange juice blend (pH: 3.8; 9.8°Brix; 707 NTU; absorption coefficient: 0.17 cm-1). Yeast induced damage by single UV-C and mild heat (H) and the combined treatment UV-C/H, was investigated by flow cytometry (FC) and transmission electron microscopy (TEM). When studying induced damage by FC, cells were labeled with fluorescein diacetate (FDA) and propidium iodide (PI) to monitor membrane integrity and esterase activity. UV-C/H provoked up to 4.7 log-reductions of S. cerevisiae; whereas, only 2.6-3.3 log-reductions were achieved by single UV-C and H treatments. FC revealed a shift with treatment time from cells with esterase activity and intact membrane to cells with permeabilized membrane. This shift was more noticeable in peptone water and UV-C/H treated juice. In the UV-C treated juice, double stained cells were detected, suggesting the possibility of being sub-lethally damaged, with compromised membrane but still metabolically active. TEM images of treated cells revealed severe damage, encompassing coagulated inner content, disorganized lumen and cell debris. FC and TEM provided additional information regarding degree and type of damage, complementing information revealed by the traditional plate count technique.


Assuntos
Citrus sinensis/microbiologia , Daucus carota/microbiologia , Conservação de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/efeitos da radiação , Citrus sinensis/química , Daucus carota/química , Citometria de Fluxo , Temperatura Alta , Viabilidade Microbiana/efeitos da radiação , Microscopia Eletrônica de Transmissão , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/ultraestrutura , Raios Ultravioleta
8.
Rev Argent Microbiol ; 50(1): 3-11, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28728873

RESUMO

The purpose of this study was to analyze the response of different initial contamination levels of Alicyclobacillus acidoterrestris ATCC 49025 spores in apple juice as affected by pulsed light treatment (PL, batch mode, xenon lamp, 3pulses/s, 0-71.6J/cm2). Biphasic and Weibull frequency distribution models were used to characterize the relationship between inoculum size and treatment time with the reductions achieved after PL exposure. Additionally, a second order polynomial model was computed to relate required PL processing time to inoculum size and requested log reductions. PL treatment caused up to 3.0-3.5 log reductions, depending on the initial inoculum size. Inactivation curves corresponding to PL-treated samples were adequately characterized by both Weibull and biphasic models (Radj2 94-96%), and revealed that lower initial inoculum sizes were associated with higher inactivation rates. According to the polynomial model, the predicted time for PL treatment increased exponentially with inoculum size.


Assuntos
Alicyclobacillus , Bebidas , Malus , Esporos Bacterianos , Contaminação de Alimentos , Microbiologia de Alimentos
9.
Food Microbiol ; 65: 83-94, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28400024

RESUMO

This study analyzed the effect of single ultrasound (US) (600 W, 20 kHz and 95.2 µm wave amplitude, 10 or 30 min at 20 or 44 ± 1 °C), or combined with pulsed light technology (PL) with controlled heat build-up (Xenon lamp, 3 pulses/s, 71.6 J/cm2, temperature ranges: 2-20 ± 1 °C and 44-56 ± 1 °C) on the inactivation of Saccharomyces cerevisiae KE 162 cells in commercial (pH: 3.5 ± 0.1; 12.5 ± 0.1 °Brix) and freshly pressed (pH: 3.4 ± 0.1; 12.6 ± 0.1 °Brix) apple juices. Structural damages were analyzed by transmission electronic microscopy (TEM) and induced damage by flow cytometry (FC). Cells were labeled with fluorescein diacetate (FDA) and propidium iodide (PI) for monitoring membrane integrity and esterase activity. US+PL treatment at the highest heat build-up led up to 6.4 and 5.8 log-cycles of yeast reduction in commercial and freshly apple juices, respectively. TEM images of treated cells revealed severe damage, encompassing loss and coagulated inner content and cell debris. In addition, FC revealed a shift of yeasts cells with esterase activity and intact membrane to cells with permeabilized membrane. This effect was more notorious after single 30-min US and all combined US+PL treatments, as 91.6-99.0% of treated cells showed compromised membrane. Additionally, heat build-up enhanced this shift when applying 10 min US (20 °C) in both juices.


Assuntos
Conservação de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Luz , Malus/microbiologia , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/efeitos da radiação , Ondas Ultrassônicas , Contagem de Colônia Microbiana , Esterases/metabolismo , Citometria de Fluxo , Microbiologia de Alimentos , Temperatura Alta , Viabilidade Microbiana , Microscopia Eletrônica de Transmissão , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/ultraestrutura
10.
Food Microbiol ; 46: 635-642, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25475338

RESUMO

The aim of this study was to evaluate the effect of ultrasound (US) (600 W, 20 kHz and 95.2 µm wave amplitude; 10 or 30 min at 20, 30 or 44 ± 1 °C) and pulsed light (PL) (Xenon lamp; 3 pulses/s; 0.1 m distance; 2.4 J/cm(2)-71.6 J/cm(2); initial temperature 2, 30, 44 ± 1 °C) on the inactivation of Alicyclobacillus acidoterrestris ATCC 49025 spores and Saccharomyces cerevisiae KE162 inoculated in commercial (pH: 3.5; 12.5 °Brix) and natural squeezed (pH: 3.4; 11.8 °Brix) apple juices. Inactivation depended on treatment time, temperature, microorganism and matrix. Combination of these technologies led up to 3.0 log cycles of spore reduction in commercial apple juice and 2.0 log cycles in natural juice; while for S. cerevisiae, 6.4 and 5.8 log cycles of reduction were achieved in commercial and natural apple juices, respectively. In natural apple juice, the combination of US + 60 s PL at the highest temperature build-up (56 ± 1 °C) was the most effective treatment for both strains. In commercial apple juice, US did not contribute to further inactivation of spores, but significantly reduced yeast population. Certain combinations of US + PL kept on good microbial stability under refrigerated conditions for 15 days.


Assuntos
Bebidas/microbiologia , Conservação de Alimentos/métodos , Malus/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/efeitos da radiação , Conservação de Alimentos/instrumentação , Luz , Ultrassom , Leveduras/crescimento & desenvolvimento , Leveduras/efeitos da radiação
12.
Nano Lett ; 13(7): 3420-5, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23786155

RESUMO

Nanoscale Pt-Ni bimetallic octahedra with controlled sizes have been actively explored in recent years owning to their outstanding activity for the oxygen reduction reaction (ORR). Here we report the synthesis of uniform 9 nm Pt-Ni octahedra with the use of oleylamine and oleic acid as surfactants and W(CO)6 as a source of CO that can promote the formation of {111} facets in the presence of Ni. Through the introduction of benzyl ether as a solvent, the coverage of both surfactants on the surface of resultant Pt-Ni octahedra was significantly reduced while the octahedral shape was still attained. By further removing the surfactants through acetic acid treatment, we observed a specific activity 51-fold higher than that of the state-of-the-art Pt/C catalyst for the ORR at 0.93 V, together with a record high mass activity of 3.3 A mgPt(-1) at 0.9 V (the highest mass activity reported in the literature was 1.45 A mgPt(-1)). Our analysis suggests that this great enhancement of ORR activity could be attributed to the presence of a clean, well-preserved (111) surface for the Pt-Ni octahedra.

13.
Nat Commun ; 15(1): 5194, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890271

RESUMO

Resistance to clinical malaria takes years to develop even in hyperendemic regions and sterilizing immunity has rarely been observed. To evaluate the maturation of the host response against controlled repeat exposures to P. falciparum (Pf) NF54 strain-infected mosquitoes, we systematically monitored malaria-naïve participants through an initial exposure to uninfected mosquitoes and 4 subsequent homologous exposures to Pf-infected mosquitoes over 21 months (n = 8 males) (ClinicalTrials.gov# NCT03014258). The primary outcome was to determine whether protective immunity against parasite infection develops following repeat CHMI and the secondary outcomes were to track the clinical signs and symptoms of malaria and anti-Pf antibody development following repeat CHMI. After two exposures, time to blood stage patency increases significantly and the number of reported symptoms decreases indicating the development of clinical tolerance. The time to patency correlates positively with both anti-Pf circumsporozoite protein (CSP) IgG and CD8 + CD69+ effector memory T cell levels consistent with partial pre-erythrocytic immunity. IFNγ levels decrease significantly during the participants' second exposure to high blood stage parasitemia and could contribute to the decrease in symptoms. In contrast, CD4-CD8 + T cells expressing CXCR5 and the inhibitory receptor, PD-1, increase significantly after subsequent Pf exposures, possibly dampening the memory response and interfering with the generation of robust sterilizing immunity.


Assuntos
Malária Falciparum , Plasmodium falciparum , Proteínas de Protozoários , Humanos , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Malária Falciparum/sangue , Plasmodium falciparum/imunologia , Masculino , Proteínas de Protozoários/imunologia , Animais , Adulto , Anticorpos Antiprotozoários/imunologia , Anticorpos Antiprotozoários/sangue , Interferon gama/metabolismo , Interferon gama/imunologia , Feminino , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Adulto Jovem , Linfócitos T CD8-Positivos/imunologia , Mosquitos Vetores/parasitologia , Mosquitos Vetores/imunologia , Anopheles/parasitologia
14.
Antioxidants (Basel) ; 13(1)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275652

RESUMO

Antioxidant defenses in biological systems ensure redox homeostasis, regulating baseline levels of reactive oxygen and nitrogen species (ROS and RNS). Oxidative stress (OS), characterized by a lack of antioxidant defenses or an elevation in ROS and RNS, may cause a modification of biomolecules, ROS being primarily absorbed by proteins. As a result of both genome and environment interactions, proteomics provides complete information about a cell's proteome, which changes continuously. Besides measuring protein expression levels, proteomics can also be used to identify protein modifications, localizations, the effects of added agents, and the interactions between proteins. Several oxidative processes are frequently used to modify proteins post-translationally, including carbonylation, oxidation of amino acid side chains, glycation, or lipid peroxidation, which produces highly reactive alkenals. Reactive alkenals, such as 4-hydroxy-2-nonenal, are added to cysteine (Cys), lysine (Lys), or histidine (His) residues by a Michael addition, and tyrosine (Tyr) residues are nitrated and Cys residues are nitrosylated by a Michael addition. Oxidative and nitrosative stress have been implicated in many neurodegenerative diseases as a result of oxidative damage to the brain, which may be especially vulnerable due to the large consumption of dioxygen. Therefore, the current methods applied for the detection, identification, and quantification in redox proteomics are of great interest. This review describes the main protein modifications classified as chemical reactions. Finally, we discuss the importance of redox proteomics to health and describe the analytical methods used in redox proteomics.

15.
bioRxiv ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38895311

RESUMO

Alterations induced by maternal immune activation (MIA) during gestation impact the subsequent neurodevelopment of progeny, a process that in humans, has been linked to the development of several neuropsychiatric conditions. To undertake a comprehensive examination of the molecular mechanisms governing MIA, we have devised an in vitro model based on neural stem cells (NSCs) sourced from fetuses carried by animals subjected to Poly I:C treatment. These neural progenitors demonstrate proliferative capacity and can be effectively differentiated into both neurons and glial cells. Transcriptomic, proteomic, and phosphoproteomic analyses conducted on these cellular models, in conjunction with counterparts from control treatments, revealed discernible shifts in the expression levels of a specific subset of proteins implicated in neuronal function. Noteworthy, we found an absence of congruence between these alterations at the transcriptomic level, suggesting that differences in protein translation contribute to the observed dysregulation. Furthermore, the phosphoproteomic data highlighted a discernible discrepancy in the basal phosphorylation of proteins between differentiated cells from both experimental groups, particularly within proteins associated with cytoskeletal architecture and synaptic functionality, notably those belonging to the MAP family. Observed alterations in MAP phosphorylation were found to potentially have functional consequences as they correlate with changes in neuronal plasticity and the establishment of neuronal synapses. Our data agrees with previous published observations and further underscore the importance of MAP2 phosphorylation state on its function and the impact that this protein has in neuronal structure and function.

16.
Acta Neuropathol Commun ; 12(1): 32, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395965

RESUMO

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are clinically linked major neurodegenerative diseases. Notably, TAR DNA-binding protein-43 (TDP43) accumulations are hallmark pathologies of FTD/ALS and mutations in the gene encoding TDP43 cause familial FTD/ALS. There are no cures for FTD/ALS. FTD/ALS display damage to a broad range of physiological functions, many of which are regulated by signaling between the endoplasmic reticulum (ER) and mitochondria. This signaling is mediated by the VAPB-PTPIP51 tethering proteins that serve to recruit regions of ER to the mitochondrial surface so as to facilitate inter-organelle communications. Several studies have now shown that disrupted ER-mitochondria signaling including breaking of the VAPB-PTPIP51 tethers are features of FTD/ALS and that for TDP43 and other familial genetic FTD/ALS insults, this involves activation of glycogen kinase-3ß (GSK3ß). Such findings have prompted suggestions that correcting damage to ER-mitochondria signaling and the VAPB-PTPIP51 interaction may be broadly therapeutic. Here we provide evidence to support this notion. We show that overexpression of VAPB or PTPIP51 to enhance ER-mitochondria signaling corrects mutant TDP43 induced damage to inositol 1,4,5-trisphosphate (IP3) receptor delivery of Ca2+ to mitochondria which is a primary function of the VAPB-PTPIP51 tethers, and to synaptic function. Moreover, we show that ursodeoxycholic acid (UDCA), an FDA approved drug linked to FTD/ALS and other neurodegenerative diseases therapy and whose precise therapeutic target is unclear, corrects TDP43 linked damage to the VAPB-PTPIP51 interaction. We also show that this effect involves inhibition of TDP43 mediated activation of GSK3ß. Thus, correcting damage to the VAPB-PTPIP51 tethers may have therapeutic value for FTD/ALS and other age-related neurodegenerative diseases.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Doenças Neurodegenerativas , Proteínas de Transporte Vesicular , Humanos , Esclerose Lateral Amiotrófica/patologia , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Sinapses/patologia , Proteinopatias TDP-43/metabolismo , Proteínas de Transporte Vesicular/genética
17.
Phys Chem Chem Phys ; 15(36): 15078-90, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23925477

RESUMO

A comprehensive experimental study was conducted on the dealloying of PdNi6 nanoparticles under various conditions. A two-stage dealloying protocol was developed to leach >95% of Ni while minimizing the dissolution of Pd. The final structure of the dealloyed particle was strongly dependent on the acid used and temperature. When H2SO4 and HNO3 solutions were used in the first stage of dealloying, solid and porous particles were generated, respectively. The porous particles have a 3-fold higher electrochemical surface area per Pd mass than the solid ones. The dealloyed PdNi6 nanoparticles were then used as a core material for the synthesis of core-shell catalysts. These catalysts were synthesized in gram-size batches and involved Pt displacement of an underpotentially deposited (UPD) Cu monolayer. The resulting materials were characterized by scanning transmission electron microscopy (STEM) and in situ X-ray diffraction (XRD). The oxygen reduction reaction (ORR) activity of the core-shell catalysts is 7-fold higher than the state-of-the-art Pt/C. The high activity was confirmed by a more than 40 mV improvement in fuel cell performance with a Pt loading of 0.1 mg cm(-2) by using the core-shell catalysts.

18.
Int J Food Microbiol ; 386: 110024, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36446270

RESUMO

Pasteurized sports drinks and other fruit-based beverages are susceptible to deterioration due to thermal processing ineffectiveness to inactivate certain spoilage microorganisms, like Alicyclobacillus acidoterrestris. This represents a major challenge for the beverage industry. The goals of this study were to: i) investigate the UV-C inactivation (annular thin film unit, actinometrical delivered fluence: 795-1270 mJ/cm2, 10-15 min, 20 °C, 1.8 L/h, Reh = 391-1067, recirculation mode operation) and the evolution during refrigerated storage of A. acidoterrestris ATCC 49025 spores and single or composite Escherichia coli ATCC 25922 in isotonic sports drinks (ISDs) made from orange (orange-ISD, UVT% = 81) or orange-banana-mango-kiwi-strawberry-lemon juices (multi-fruit-ISD, UVT% = 91), compared to a turbid orange-tangerine juice (OT juice, UVT% = 40); ii) assess the effect of pH, °Brix, A254nm, turbidity, colour and particle size of the ISDs and juice on microbial inactivation, iii) evaluate the evolution of native microbiota during cold storage, iv) investigate the Coroller, biphasic, Weibull, and Weibull-plus-tail models' ability to describe microbial inactivation and v) measure 5-hydroxymethylfurfural (HMF) formation. The modified biodosimetry method was used to calculate the germicidal UV-C fluences. Heat pasteurization (T-coil, 80 °C/6 min) was evaluated as the control treatment. UV-C was highly effective at inactivating E. coli as 4.1-5.1 and 4.5-5.6 log reductions were determined in the multi-fruit-ISD and orange-ISD, respectively, barely impacted by the background microbiota. No significant differences were recorded for the inactivation of E. coli in the UV-C and T-coil systems. Whereas, a significantly higher inactivation of A. acidoterrestris spores was achieved by UV-C (3.7-4.0 log reductions), compared to the negligible one achieved by the thermal treatment. Even though E. coli inactivation curves were similar in shape, UV-C was less effective when a cocktail of other E. coli strains was present. In comparison to the OT juice, the ISDs' inactivation kinetics were markedly different in shape, with a rapid decrease in population during the first minutes of treatment. The germicidal fluence (Hd biod) corresponding to A. acidoterrestris (19.1 mJ/cm2) was selected as it was higher than the one obtained for E. coli (11.0 mJ/cm2). UV-C induced 2.8- or 1.3 and 2.3- or 0.8 log-reductions of total aerobes or moulds and yeasts in the multi-fruit-ISD and orange-ISD, respectively. Compared to the other models, the Coroller and biphasic models showed a better fit and more accurate parameter estimates. UV-C-induced HMF production was not significant in the ISDs. The current study found that the UV-C treatment was more effective than typical heat pasteurization for inactivating A. acidoterrestris spores in isotonic drinks, following a similar trend for E. coli and native microbiota.


Assuntos
Alicyclobacillus , Citrus sinensis , Escherichia coli , Frutas , Esporos Bacterianos , Bebidas
19.
Epidemics ; 45: 100721, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890441

RESUMO

Assessing the factors responsible for differences in outbreak severity for the same pathogen is a challenging task, since outbreak data are often incomplete and may vary in type across outbreaks (e.g., daily case counts, serology, cases per household). We propose that outbreaks described with varied data types can be directly compared by using those data to estimate a common set of epidemiological parameters. To demonstrate this for chikungunya virus (CHIKV), we developed a realistic model of CHIKV transmission, along with a Bayesian inference method that accommodates any type of outbreak data that can be simulated. The inference method makes use of the fact that all data types arise from the same transmission process, which is simulated by the model. We applied these tools to data from three real-world outbreaks of CHIKV in Italy, Cambodia, and Bangladesh to estimate nine model parameters. We found that these populations differed in several parameters, including pre-existing immunity and house-to-house differences in mosquito activity. These differences resulted in posterior predictions of local CHIKV transmission risk that varied nearly fourfold: 16% in Italy, 28% in Cambodia, and 62% in Bangladesh. Our inference method and model can be applied to improve understanding of the epidemiology of CHIKV and other pathogens for which outbreaks are described with varied data types.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Febre de Chikungunya/epidemiologia , Teorema de Bayes , Surtos de Doenças
20.
Front Cell Dev Biol ; 10: 915931, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693938

RESUMO

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are two major neurodegenerative diseases. FTD is the second most common cause of dementia and ALS is the most common form of motor neuron disease. These diseases are now known to be linked. There are no cures or effective treatments for FTD or ALS and so new targets for therapeutic intervention are required but this is hampered by the large number of physiological processes that are damaged in FTD/ALS. Many of these damaged functions are now known to be regulated by signaling between the endoplasmic reticulum (ER) and mitochondria. This signaling is mediated by "tethering" proteins that serve to recruit ER to mitochondria. One tether strongly associated with FTD/ALS involves an interaction between the ER protein VAPB and the mitochondrial protein PTPIP51. Recent studies have shown that ER-mitochondria signaling is damaged in FTD/ALS and that this involves breaking of the VAPB-PTPIP51 tethers. Correcting disrupted tethering may therefore correct many other downstream damaged features of FTD/ALS. Here, we review progress on this topic with particular emphasis on targeting of the VAPB-PTPIP51 tethers as a new drug target.

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