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1.
J Chem Phys ; 161(13)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39356064

RESUMO

The valence and core photoelectron spectra of three substituted disulfide systems, α-lipoic acid, trans-4,5-dihydroxy-1,2-dithiane, and di-Boc-cystamine, are presented alongside detailed theoretical analysis based on equation-of-motion coupled-cluster singles doubles for ionization potentials and the nuclear ensemble approach. A comparison of the linear and five- and six-membered ring cyclic structures reveals that the energetic separation of the non-bonding sulfur orbitals can be used to calculate a reliable estimate of the C-S-S-C dihedral angle, even for substituted disulfides, and that the sulfur 2p, oxygen 1s, and valence band photoelectron spectra are a useful site-specific probe of hydrogen bonding.

2.
Front Neurosci ; 18: 1483708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39381683

RESUMO

The brain's high demand for energy necessitates tightly regulated metabolic pathways to sustain physiological activity. Glucose, the primary energy substrate, undergoes complex metabolic transformations, with mitochondria playing a central role in ATP production via oxidative phosphorylation. Dysregulation of this metabolic interplay is implicated in Alzheimer's disease (AD), where compromised glucose metabolism, oxidative stress, and mitochondrial dysfunction contribute to disease progression. This review explores the intricate bioenergetic crosstalk between astrocytes and neurons, highlighting the function of mitochondrial uncoupling proteins (UCPs), particularly UCP4, as important regulators of brain metabolism and neuronal function. Predominantly expressed in the brain, UCP4 reduces the membrane potential in the inner mitochondrial membrane, thereby potentially decreasing the generation of reactive oxygen species. Furthermore, UCP4 mitigates mitochondrial calcium overload and sustains cellular ATP levels through a metabolic shift from mitochondrial respiration to glycolysis. Interestingly, the levels of the neuronal UCPs, UCP2, 4 and 5 are significantly reduced in AD brain tissue and a specific UCP4 variant has been associated to an increased risk of developing AD. Few studies modulating the expression of UCP4 in astrocytes or neurons have highlighted protective effects against neurodegeneration and aging, suggesting that pharmacological strategies aimed at activating UCPs, such as protonophoric uncouplers, hold promise for therapeutic interventions in AD and other neurodegenerative diseases. Despite significant advances, our understanding of UCPs in brain metabolism remains in its early stages, emphasizing the need for further research to unravel their biological functions in the brain and their therapeutic potential.

3.
Midwifery ; 140: 104201, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39395313

RESUMO

BACKGROUND: Induction of labour (IOL) and birth intervention is increasingly conducted in Australia, and rates of maternal dissatisfaction and birth trauma are also on the rise. METHODS: The Birth Experience Study (BESt) national survey was conducted to explore women's experiences of birthing in Australia. This content analysis categorises components pertaining to IOL, and women's responses to the open-ended question: "Would you do anything different if you were to have another baby?" FINDINGS: In total, 591 responses on IOL resulted in 819 coded comments being coded into multiple categories/subcategories. In the first main category 'increasing the chance of a spontaneous labour next time by resisting IOL' (93.3 %), three subcategories were identified: 'I would resist the pressure or refuse, especially if not a good indication' (54.8 %, 419); 'I will await spontaneous onset or delay the IOL until later' (25.0 %, 191); and 'I will be better informed next time' (20.2 %, 154). In the second main category 'accepting IOL was necessary or desirable' (6.7 %), two subcategories were identified: 'my IOL was justified or desired' (38.2 %, 21) and 'my IOL was justified or desired, but if there is a next time, I'd want more say in what happens' (61.8 %, 34). CONCLUSION: Overwhelmingly women expressed a desire to avoid IOL, along with the intention to: resist pressure, allow more time for spontaneous labour onset, and arm themselves with more knowledge to advocate against non-medically indicated justifications. Amongst the minority accepting of their previous IOLs, the majority stated wanting more say regarding when and how IOL was conducted.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39271639

RESUMO

BACKGROUND AND OBJECTIVES: Voriconazole administered concomitantly with flucloxacillin may result in subtherapeutic plasma concentrations as shown in a patient with Staphylococcus aureus sepsis and a probable pulmonary aspergillosis. After switching our patient to posaconazole, therapeutic concentrations were reached. The aim of this study was to first test our hypothesis that flucloxacillin competes with voriconazole not posaconazole for binding to albumin ex vivo, leading to lower total concentrations in plasma. METHODS: A physiologically based pharmacokinetic (PBPK) model was then applied to predict the mechanism of action of the drug-drug interaction (DDI). The model included non-linear hepatic metabolism and the effect of a severe infectious disease on cytochrome P450 (CYP) enzymes activity. RESULTS: The unbound voriconazole concentration remained unchanged in plasma after adding flucloxacillin, thereby rejecting our hypothesis of albumin-binding site competition. The PBPK model was able to adequately predict the plasma concentration of both voriconazole and posaconazole over time in healthy volunteers. Upregulation of CYP3A4, CYP2C9, and CYP2C19 through the pregnane X receptor (PXR) gene by flucloxacillin resulted in decreased voriconazole plasma concentrations, reflecting the DDI observations in our patient. Posaconazole metabolism was not affected, or was only limitedly affected, by the changes through the PXR gene, which agrees with the observed plasma concentrations within the target range in our patient. CONCLUSIONS: Ex vivo experiments reported that the unbound voriconazole plasma concentration remained unchanged after adding flucloxacillin. The PBPK model describes the potential mechanism driving the drug-drug and drug-disease interaction of voriconazole and flucloxacillin, highlighting the large substantial influence of flucloxacillin on the PXR gene and the influence of infection on voriconazole plasma concentrations, and suggests a more limited effect on other triazoles.

5.
PLoS One ; 19(9): e0309337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39226247

RESUMO

BACKGROUND: Multi-component CS programs incorporating practice of activities of daily living (ADL) into intervention have reported benefits for ADL outcomes in individuals living with mild-to-moderate dementia. A randomised controlled trial (RCT) within community occupational therapy services in Ireland, is planned to evaluate the effects of CS-ADL, an ADL-focused, multi-component CS program, on ADL outcomes for individuals living with mild-to-moderate dementia. METHOD: A single-blind RCT with a calculated sample size of 34 participants has been planned to compare the effects of CS-ADL versus treatment as usual on the outcomes of basic ADLs and instrumental ADLs. Cognition, mood, communication, and quality of life will also be evaluated as secondary outcomes. CS-ADL sessions will run once weekly for a total of seven weeks, lasting approximately two hours each. Outcome data will be collected at baseline, within sessions and post-intervention at week eight. Descriptive statistics will be used to analyse the data. This study has been registered at clinicaltrials.gov (NCT06147479). DISCUSSION: CS programs are commonly conducted by occupational therapists working with individuals living with mild-to-moderate dementia. This study aims to demonstrate the effectiveness of a multi-component CS program delivered through an occupational therapy lens, potentially influencing the approach to CS and ADL interventions undertaken by occupational therapists.


Assuntos
Atividades Cotidianas , Demência , Qualidade de Vida , Idoso , Feminino , Humanos , Masculino , Cognição , Demência/terapia , Demência/psicologia , Terapia Ocupacional/métodos , Método Simples-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Data Brief ; 57: 110867, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39290426

RESUMO

This dataset presents the outputs of a series of experiments conducted varying combinations of two versions of the High Resolution Transmission (HITRAN) database (2016 and 2020) and two versions of the MT_CKD water vapor (WV) continuum model (3.2 and 4.1.1) across five distinct model atmospheres. The primary objective of compiling this dataset was to assess the impacts of updated spectroscopic parameters and water vapor continuum models on atmospheric radiative transfer calculations. The line-by-line calculations were performed by the Reference Foward Model (RFM). Key atmospheric gases, namely H2O, CO2, O3, CH4, CO, N2O, and O2, are prescribed at each atmospheric model. The dataset includes calculations with all gases present as well as experiments removing individual gases (specifically, CO2, O3, and H2O). It gathers upward and downward radiation fluxes, and cooling rates. The dataset is available in a compressed .tar file format, where each file contains 880 individual text files representing specific atmospheric heights. This collection is designed to facilitate further research in atmospheric science, particularly for validating other radiative transfer models and improving the understanding of atmospheric energy dynamics.

7.
Parasit Vectors ; 17(1): 336, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127700

RESUMO

BACKGROUND: Giardiasis, caused by the protozoan parasite Giardia intestinalis, often presents a treatment challenge, particularly in terms of resistance to metronidazole. Despite extensive research, markers for metronidazole resistance have not yet been identified. METHODS: This study analysed 28 clinical samples of G. intestinalis from sub-assemblage AII, characterised by varying responses to metronidazole treatment. We focussed on copy number variation (CNV) of the multi-copy flavohemoprotein gene, analysed using digital polymerase chain reaction (dPCR) and next generation sequencing (NGS). Additionally, chromosomal ploidy was tested in 18 of these samples. Flavohemoprotein CNV was also assessed in 17 samples from other sub-assemblages. RESULTS: Analyses revealed variable CNVs of the flavohemoprotein gene among the isolates, with no correlation to clinical metronidazole resistance. Discrepancies in CNVs detected from NGS data were attributed to biases linked to the whole genome amplification. However, dPCR helped to clarify these discrepancies by providing more consistent CNV data. Significant differences in flavohemoprotein CNVs were observed across different G. intestinalis sub-assemblages. Notably, Giardia exhibits a propensity for aneuploidy, contributing to genomic variability within and between sub-assemblages. CONCLUSIONS: The complexity of the clinical metronidazole resistance in Giardia is influenced by multiple genetic factors, including CNVs and aneuploidy. No significant differences in the CNV of the flavohemoprotein gene between isolates from metronidazole-resistant and metronidazole-sensitive cases of giardiasis were found, underscoring the need for further research to identify reliable genetic markers for resistance. We demonstrate that dPCR and NGS are robust methods for analysing CNVs and provide cross-validating results, highlighting their utility in the genetic analyses of this parasite.


Assuntos
Antiprotozoários , Variações do Número de Cópias de DNA , Resistência a Medicamentos , Giardia lamblia , Giardíase , Metronidazol , Giardia lamblia/genética , Giardia lamblia/efeitos dos fármacos , Metronidazol/farmacologia , Resistência a Medicamentos/genética , Humanos , Giardíase/parasitologia , Giardíase/tratamento farmacológico , Antiprotozoários/farmacologia , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Protozoários/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-39134371

RESUMO

BACKGROUND AND PURPOSE: The Total Calcification Score (TCS) is a visual rating scale to measure Primary Familial Brain Calcification (PFBC) related calcification severity on Computed Tomography (CT). We investigated the inter-and intrarater agreement of a modified TCS. MATERIALS AND METHODS: Patients aged ≥18 years with PFBC or Fahr's syndrome who visited the outpatient clinic of a Dutch academic hospital were included. The TCS was modified, for example by adding hippocampal calcification, and ranged from 0 to 95 points. Fifteen raters evaluated all CTs, of whom three evaluated the CTs twice. Their Entrustable Professional Activity (EPA) level ranged from II (medical student) to V (neuroradiologist). Agreement was assessed using the intraclass correlation coefficient (ICC) for the total score. Kendall's W and weighted Cohen's Kappa were used to determine the inter- and intrarater agreement for individual locations, respectively. RESULTS: Forty patients were included (mean age 60 years, 53% female). The median modified TCS was 34 (range 4-76). For all EPA levels, the interrater agreement of the modified TCS was excellent (ICC=0.97 (95% CI 0.95-0.98)). Kendall's W's were good to excellent for commonly affected locations, but poor to moderate for less commonly affected locations for raters with lower levels of expertise. The intrarater agreement of the modified TCS was excellent. Kappa's of most locations were substantial to almost perfect. CONCLUSIONS: The modified TCS can be used with excellent reproducibility of the overall amount of brain calcifications and with limited training, although for some individual calcification locations more expertise is needed. ABBREVIATIONS: CI, Confidence Interval; CT, Computed Tomography; EPA, Entrustable Professional Activity; IBGC, Idiopathic Basal Ganglia Calcification; ICC, Intraclass Correlation Coefficient; IQR, Interquartile Range; PFBC, Primary Familial Brain Calcification; SD, Standard Deviation, TCS, Total Calcification Score; UMCU, University Medical Center Utrecht.

9.
Curr Dev Nutr ; 8(7): 103792, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39050780

RESUMO

Background: Nonquantitative list-based or open 24-h recalls (24-HRs) have been shown to overestimate the prevalence of Minimum Dietary Diversity for Women (MDD-W), as compared with direct quantitative observations. However, the main sources of error are unknown. Objectives: To assess the measurement agreement of proxy data collection methods for MDD-W, as compared with weighed food records (WFRs). Methods: Applying a noninferiority design, data were collected from 431 nonpregnant females in Ethiopia. MDD-W estimates from both proxy data collection methods were compared with the WFR prevalence by McNemar's chi-square tests, Cohen's Kappa, and receiver operator characteristic analyses. Ten-point food group diversity scores (FGDS) were compared by Bland-Altman plots, Wilcoxon matched-pairs tests, and weighted Kappa. Food group misclassifications were partitioned into errors related to respondent biases or the questionnaire development. Results: List-based and open 24-HRs overreported MDD-W by 8 and 4 percentage points, respectively, as compared with WFR (objective MDD-W prevalence: 8%). Furthermore, list-based 24-HRs overestimated FGDS by 0.4 points (limits of agreement [LOA]: -1.1, 2.0), whereas open 24-HRs led to a 0.3 point (LOA: -1.2, 1.7) overestimate. Food groups most likely to be misreported using proxy data collection methods were "pulses," "nuts and seeds," "dairy products," and "other fruits." Underreporting of consumption occurred among <4% of females for all food groups. Furthermore, respondent biases were the predominant cause of food group overreporting, except for the "pulses" and "other vegetables" food groups, where food items incorrectly included on the food list were the main source of errors. Conclusions: Food group consumption misclassifications by proxy data collection methods were mainly attributable to females overreporting consumption because of respondent biases or the criterion for foods to be counted, rather than the suboptimal development of the food list in Ethiopia. To obtain precise and accurate MDD-W estimates at the (sub)national level, rigorous context-specific food list development, questionnaire pilot testing, and enumerator training are recommended to mitigate identified biases.

10.
Cancers (Basel) ; 16(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39001392

RESUMO

Rapidly proliferative processes in mammalian tissues including tumorigenesis and embryogenesis rely on the glycolytic pathway for energy and biosynthetic precursors. The enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3) plays an important regulatory role in glycolysis by activating the key rate-limiting glycolytic enzyme, 6-phosphofructo-1-kinase (PFK-1). We have previously determined that decreased PFKFB3 expression reduced glycolysis and growth in transformed cells in vitro and suppressed xenograft growth in vivo. In earlier studies, we created a constitutive knockout mouse to interrogate the function of PFKFB3 in vivo but failed to generate homozygous offspring due to the requirement for PFKFB3 for embryogenesis. We have now developed a novel transgenic mouse model that exhibits inducible homozygous pan-tissue Pfkfb3 gene deletion (Pfkfb3fl/fl). We have induced Pfkfb3 genomic deletion in these mice and found that it effectively decreased PFKFB3 expression and activity. To evaluate the functional consequences of Pfkfb3 deletion in vivo, we crossed Cre-bearing Pfkfb3fl/fl mice with oncogene-driven tumor models and found that Pfkfb3 deletion markedly decreased their glucose uptake and growth. In summary, our studies reveal a critical regulatory function for PFKFB3 in glycolysis and tumorigenesis in vivo and characterize an effective and powerful model for further investigation of its role in multiple biological processes.

11.
Genome Biol Evol ; 16(8)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39031594

RESUMO

Transposable elements (TEs) are repetitive DNA sequences which create mutations and generate genetic diversity across the tree of life. In amniote vertebrates, TEs have been mainly studied in mammals and birds, whose genomes generally display low TE diversity. Squamates (Order Squamata; including ∼11,000 extant species of lizards and snakes) show as much variation in TE abundance and activity as they do in species and phenotypes. Despite this high TE activity, squamate genomes are remarkably uniform in size. We hypothesize that novel, lineage-specific genome dynamics have evolved over the course of squamate evolution. To understand the interplay between TEs and host genomes, we analyzed the evolutionary history of the chicken repeat 1 (CR1) retrotransposon, a TE family found in most tetrapod genomes which is the dominant TE in most reptiles. We compared 113 squamate genomes to the genomes of turtles, crocodilians, and birds and used ancestral state reconstruction to identify shifts in the rate of CR1 copy number evolution across reptiles. We analyzed the repeat landscapes of CR1 in squamate genomes and determined that shifts in the rate of CR1 copy number evolution are associated with lineage-specific variation in CR1 activity. We then used phylogenetic reconstruction of CR1 subfamilies across amniotes to reveal both recent and ancient CR1 subclades across the squamate tree of life. The patterns of CR1 evolution in squamates contrast other amniotes, suggesting key differences in how TEs interact with different host genomes and at different points across evolutionary history.


Assuntos
Evolução Molecular , Genoma , Répteis , Retroelementos , Animais , Répteis/genética , Répteis/classificação , Filogenia , Lagartos/genética , Galinhas/genética
12.
Br J Anaesth ; 133(3): 519-529, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38971713

RESUMO

BACKGROUND: Guideline adherence in the medical field leaves room for improvement. Digitalised decision support helps improve compliance. However, the complex nature of the guidelines makes implementation in clinical practice difficult. METHODS: This single-centre prospective study included 204 adult ASA physical status 3-4 patients undergoing elective noncardiac surgery at a German university hospital. Agreement of clearance for surgery between a guideline expert and a digital guideline support tool was investigated. The decision made by the on-duty anaesthetists (standard approach) was assessed for agreement with the expert in a cross-over design. The main outcome was the level of agreement between digital guideline support and the expert. RESULTS: The digital guideline support approach cleared 18.1% of the patients for surgery, the standard approach cleared 74.0%, and the expert approach cleared 47.5%. Agreement of the expert decision with digital guideline support (66.7%) and the standard approach (67.6%) was fair (Cohen's kappa 0.37 [interquartile range 0.26-0.48] vs 0.31 [0.21-0.42], P=0.6). Taking the expert decision as a benchmark, correct clearance using digital guideline support was 50.5%, and correct clearance using the standard approach was 44.6%. Digital guideline support incorrectly asked for additional examinations in 31.4% of the patients, whereas the standard approach did not consider conditions that would have justified additional examinations before surgery in 29.4%. CONCLUSIONS: Strict guideline adherence for clearance for surgery through digitalised decision support inadequately considered patients, clinical context. Vague formulations, weak recommendations, and low-quality evidence complicate guideline translation into explicit rules. CLINICAL TRIAL REGISTRATION: NCT04058769.


Assuntos
Fidelidade a Diretrizes , Cuidados Pré-Operatórios , Humanos , Estudos Prospectivos , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Cuidados Pré-Operatórios/métodos , Cuidados Pré-Operatórios/normas , Adulto , Software , Procedimentos Cirúrgicos Eletivos/normas , Sistemas de Apoio a Decisões Clínicas , Estudos Cross-Over , Guias de Prática Clínica como Assunto , Técnicas de Apoio para a Decisão , Alemanha
13.
Cell ; 187(17): 4554-4570.e18, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-38981480

RESUMO

Diet impacts human health, influencing body adiposity and the risk of developing cardiometabolic diseases. The gut microbiome is a key player in the diet-health axis, but while its bacterial fraction is widely studied, the role of micro-eukaryotes, including Blastocystis, is underexplored. We performed a global-scale analysis on 56,989 metagenomes and showed that human Blastocystis exhibits distinct prevalence patterns linked to geography, lifestyle, and dietary habits. Blastocystis presence defined a specific bacterial signature and was positively associated with more favorable cardiometabolic profiles and negatively with obesity (p < 1e-16) and disorders linked to altered gut ecology (p < 1e-8). In a diet intervention study involving 1,124 individuals, improvements in dietary quality were linked to weight loss and increases in Blastocystis prevalence (p = 0.003) and abundance (p < 1e-7). Our findings suggest a potentially beneficial role for Blastocystis, which may help explain personalized host responses to diet and downstream disease etiopathogenesis.


Assuntos
Blastocystis , Dieta , Microbioma Gastrointestinal , Obesidade , Humanos , Blastocystis/metabolismo , Masculino , Feminino , Infecções por Blastocystis , Adulto , Pessoa de Meia-Idade , Intestinos/parasitologia , Intestinos/microbiologia , Doenças Cardiovasculares/prevenção & controle , Metagenoma
14.
Genome Res ; 34(6): 877-887, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38977307

RESUMO

The zoonotic parasite Cryptosporidium parvum is a global cause of gastrointestinal disease in humans and ruminants. Sequence analysis of the highly polymorphic gp60 gene enabled the classification of C. parvum isolates into multiple groups (e.g., IIa, IIc, Id) and a large number of subtypes. In Europe, subtype IIaA15G2R1 is largely predominant and has been associated with many water- and food-borne outbreaks. In this study, we generated new whole-genome sequence (WGS) data from 123 human- and ruminant-derived isolates collected in 13 European countries and included other available WGS data from Europe, Egypt, China, and the United States (n = 72) in the largest comparative genomics study to date. We applied rigorous filters to exclude mixed infections and analyzed a data set from 141 isolates from the zoonotic groups IIa (n = 119) and IId (n = 22). Based on 28,047 high-quality, biallelic genomic SNPs, we identified three distinct and strongly supported populations: Isolates from China (IId) and Egypt (IIa and IId) formed population 1; a minority of European isolates (IIa and IId) formed population 2; and the majority of European (IIa, including all IIaA15G2R1 isolates) and all isolates from the United States (IIa) clustered in population 3. Based on analyses of the population structure, population genetics, and recombination, we show that population 3 has recently emerged and expanded throughout Europe to then, possibly from the United Kingdom, reach the United States, where it also expanded. The reason(s) for the successful spread of population 3 remain elusive, although genes under selective pressure uniquely in this population were identified.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Surtos de Doenças , Cryptosporidium parvum/genética , Estados Unidos/epidemiologia , Europa (Continente)/epidemiologia , Humanos , Criptosporidiose/parasitologia , Criptosporidiose/epidemiologia , Animais , Genômica/métodos , Polimorfismo de Nucleotídeo Único , Filogenia , Sequenciamento Completo do Genoma/métodos , Genoma de Protozoário , China/epidemiologia , Egito/epidemiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-39080242

RESUMO

Prior physical activity reduces the risk of future stress-related mental health disorders including depression, anxiety, and post-traumatic stress disorder. Rodents allowed to engage in voluntary wheel running are similarly protected from behavioral consequences of stress. The present review summarizes current knowledge on mechanisms underlying exercise-induced stress resistance. A conceptual framework involving the development (during exercise) and expression (during stress) of stress resistance from exercise is proposed. During the development of stress resistance, adaptations involving multiple exercise signals and molecular mediators occur within neural circuits orchestrating various components of the stress response, which then respond differently to stress during the expression of stress resistance. Recent data indicate that the development and expression of stress resistance from exercise involve multiple independent mechanisms that depend on sex, stressor severity, and behavioral outcome. Recent insight into the role of the prefrontal cortex in exercise-induced stress resistance illustrates these multiple mechanisms. This knowledge has important implications for the design of future experiments aimed at identifying the mechanisms underlying exercise-induced stress resistance.

16.
J Extracell Vesicles ; 13(7): e12477, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988257

RESUMO

Extracellular vesicles (EVs) are shed from the plasma membrane, but the regulation and function of these EVs remain unclear. We found that oxidative stress induced by H2O2 in Hela cells stimulated filopodia formation and the secretion of EVs. EVs were small (150 nm) and labeled for CD44, indicating that they were derived from filopodia. Filopodia-derived small EVs (sEVs) were enriched with the sphingolipid ceramide, consistent with increased ceramide in the plasma membrane of filopodia. Ceramide was colocalized with neutral sphingomyelinase 2 (nSMase2) and acid sphingomyelinase (ASM), two sphingomyelinases generating ceramide at the plasma membrane. Inhibition of nSMase2 and ASM prevented oxidative stress-induced sEV shedding but only nSMase2 inhibition prevented filopodia formation. nSMase2 was S-palmitoylated and interacted with ASM in filopodia to generate ceramide for sEV shedding. sEVs contained nSMase2 and ASM and decreased the level of these two enzymes in oxidatively stressed Hela cells. A novel metabolic labeling technique for EVs showed that oxidative stress induced secretion of fluorescent sEVs labeled with NBD-ceramide. NBD-ceramide-labeled sEVs transported ceramide to mitochondria, ultimately inducing cell death in a proportion of neuronal (N2a) cells. In conclusion, using Hela cells we provide evidence that oxidative stress induces interaction of nSMase2 and ASM at filopodia, which leads to shedding of ceramide-rich sEVs that target mitochondria and propagate cell death.


Assuntos
Ceramidas , Vesículas Extracelulares , Estresse Oxidativo , Pseudópodes , Esfingomielina Fosfodiesterase , Humanos , Vesículas Extracelulares/metabolismo , Ceramidas/metabolismo , Pseudópodes/metabolismo , Pseudópodes/efeitos dos fármacos , Células HeLa , Esfingomielina Fosfodiesterase/metabolismo , Peróxido de Hidrogênio/metabolismo , Membrana Celular/metabolismo
17.
J Neurochem ; 168(9): 3063-3075, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39001667

RESUMO

APOE4 encoding apolipoprotein (Apo)E4 is the strongest genetic risk factor for Alzheimer's disease (AD). ApoE is key in intercellular lipid trafficking. Fatty acids are essential for brain integrity and cognitive performance and are implicated in neurodegeneration. We determined the sex- and age-dependent effect of AD and APOE4 on brain free fatty acid (FFA) profiles. FFA profiles were determined by LC-MS/MS in hippocampus, cortex, and cerebellum of female and male, young (≤3 months) and older (>5 months), transgenic APOE3 and APOE4 mice with and without five familial AD (FAD) mutations (16 groups; n = 7-10 each). In the different brain regions, females had higher levels than males of either saturated or polyunsaturated FFAs or both. In the hippocampus of young males, but not of older males, APOE4 and FAD each induced 1.3-fold higher levels of almost all FFAs. In young and older females, FAD and to a less extent APOE4-induced shifts among saturated, monounsaturated, and polyunsaturated FFAs without affecting total FFA levels. In cortex and cerebellum, APOE4 and FAD had only minor effects on individual FFAs. The effects of APOE4 and FAD on FFA levels and FFA profiles in the three brain regions were strongly dependent of sex and age, particularly in the hippocampus. Here, most FFAs that are affected by FAD are similarly affected by APOE4. Since APOE4 and FAD affected hippocampal FFA profiles already at young age, these APOE4-induced alterations may modulate the pathogenesis of AD.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Encéfalo , Ácidos Graxos não Esterificados , Mutação , Animais , Feminino , Humanos , Masculino , Camundongos , Fatores Etários , Envelhecimento/genética , Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Encéfalo/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Caracteres Sexuais
18.
Eur J Psychotraumatol ; 15(1): 2365030, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38904156

RESUMO

Background: Police officers encounter various potentially traumatic events (PTEs) and may be compelled to engage in actions that contradict their moral codes. Consequently, they are at risk to develop symptoms of Posttraumatic Stress Disorder (PTSD), but also moral stress or moral injury (MI). To date, MI in police officers has received limited attention.Objective: The present study sought to identify classes of MI appraisals and PTSD symptoms among police officers exposed to PTEs, while also investigating potential clinical differences between these classes.Method: For this study, 421 trauma-exposed police officers were assessed on demographics and several clinical measurements including MI appraisals (self-directed and other-directed), PTSD severity, and general psychopathology. Latent class and regression analyses were conducted to examine the presence of different classes among trauma-exposed police officers and class differentiation in terms of demographics, general psychopathology, PTSD severity, mistrust, guilt, self-punishment, and feelings of worthlessness.Results: The following five classes were identified: (1) a 'Low MI, high PTSD class' (28%), (2) a 'High MI, low PTSD class' (11%), (3) a 'High MI, high PTSD class' (17%), (4) a 'Low MI, low PTSD class' (16%), and (5) a 'High MI-other, high PTSD class' (27%). There were significant differences between the classes in terms of age, general psychopathology, PTSD severity, mistrust, guilt, and self-punishment but no differences for gender and feelings of worthlessness.Conclusion: In conclusion, we identified five classes, each exhibiting unique patterns of cognitive MI appraisals and PTSD symptoms. This underscores the criticality of measuring and identifying MI in this particular group, as it allows for tailored treatment interventions.


This study identified classes differing in terms of endorsement of MI appraisals and posttraumatic stress disorder (PTSD) symptoms among police officers exposed to potentially traumatic events.Five classes were identified, each exhibiting unique patterns of MI appraisals and PTSD symptoms.It is important to measure the presence of MI appraisals in addition to PTSD symptoms in traumatized police officers as it can inform treatment interventions.


Assuntos
Análise de Classes Latentes , Princípios Morais , Polícia , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Polícia/psicologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
19.
Discov Immunol ; 3(1): kyae008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903247

RESUMO

Direct interaction between T-cells exerts a major influence on tissue immunity and inflammation across multiple body sites including the human gut, which is highly enriched in 'unconventional' lymphocytes such as γδ T-cells. We previously reported that microbial activation of human Vγ9/Vδ2+ γδ T-cells in the presence of the mucosal damage-associated cytokine IL-15 confers the ability to promote epithelial barrier defence, specifically via induction of IL-22 expression in conventional CD4+ T-cells. In the current report, we assessed whether other cytokines enriched in the gut milieu also functionally influence microbe-responsive Vγ9/Vδ2 T-cells. When cultured in the presence of IL-21, Vγ9/Vδ2 T-cells acquired the ability to induce expression of the immunoregulatory cytokine IL-10 in both naïve and memory CD4+ T-cells, at levels surpassing those induced by monocytes or monocyte-derived DCs. These findings identify an unexpected influence of IL-21 on Vγ9/Vδ2 T-cell modulation of CD4+ T-cell responses. Further analyses suggested a possible role for CD30L and/or CD40L reverse signalling in mediating IL-10 induction by IL-21 conditioned Vγ9/Vδ2 T-cells. Our findings indicate that the local microenvironment exerts a profound influence on Vγ9/Vδ2 T-cell responses to microbial challenge, leading to induction of distinct functional profiles among CD4+ T-cells that may influence inflammatory events at mucosal surfaces. Targeting these novel pathways may offer therapeutic benefit in disorders such as inflammatory bowel disease.

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