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Acta Crystallogr F Struct Biol Commun ; 80(Pt 10): 269-277, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39291304

RESUMO

Plasmodium vivax is a major cause of malaria, which poses an increased health burden on approximately one third of the world's population due to climate change. Primaquine, the preferred treatment for P. vivax malaria, is contraindicated in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, a common genetic cause of hemolytic anemia, that affects ∼2.5% of the world's population and ∼8% of the population in areas of the world where P. vivax malaria is endemic. The Seattle Structural Genomics Center for Infectious Disease (SSGCID) conducted a structure-function analysis of P. vivax N-myristoyltransferase (PvNMT) as part of efforts to develop alternative malaria drugs. PvNMT catalyzes the attachment of myristate to the N-terminal glycine of many proteins, and this critical post-translational modification is required for the survival of P. vivax. The first step is the formation of a PvNMT-myristoyl-CoA binary complex that can bind to peptides. Understanding how inhibitors prevent protein binding will facilitate the development of PvNMT as a viable drug target. NMTs are secreted in all life stages of malarial parasites, making them attractive targets, unlike current antimalarials that are only effective during the plasmodial erythrocytic stages. The 2.3 Šresolution crystal structure of the ternary complex of PvNMT with myristoyl-CoA and a novel inhibitor is reported. One asymmetric unit contains two monomers. The structure reveals notable differences between the PvNMT and human enzymes and similarities to other plasmodial NMTs that can be exploited to develop new antimalarials.


Assuntos
Aciltransferases , Plasmodium vivax , Aciltransferases/química , Aciltransferases/metabolismo , Aciltransferases/genética , Aciltransferases/antagonistas & inibidores , Plasmodium vivax/enzimologia , Plasmodium vivax/genética , Cristalografia por Raios X , Acil Coenzima A/metabolismo , Acil Coenzima A/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Modelos Moleculares , Ligação Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/antagonistas & inibidores , Humanos , Sequência de Aminoácidos
4.
Cureus ; 16(8): e67234, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39165616

RESUMO

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that characteristically presents with progressive ulcerative lesions. The association of PG with hematological malignancies remains unclear due to its varied clinical presentation. Herein, we report the unusual case of PG in a 75-year-old male with stage III follicular diffuse large B-cell lymphoma. Seven days subsequent to his first dose of rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone (R-CHOP) therapy, he presented to the emergency department with generalized malaise, bilateral lower extremity edema, and ecchymoses with ulcerative wounds on the dorsal of his feet. Due to the rapid progression of the patient's dermatological manifestations and declining clinical status, he required serial surgical wound debridement and a biopsy, which revealed an occlusive vasculopathy with dermal and epidermal necrosis. These pathological findings, along with the patient's clinical presentation, led to the diagnosis of PG. The patient was treated with negative pressure wound therapy, steroids, and tacrolimus ointment, which led to a marked improvement in the appearance of the patient's dermatological features and clinical status.

5.
Data Brief ; 55: 110635, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39035842

RESUMO

With less than half of the world's urban population having safely managed sanitation due to the high cost and difficulty of building sewers and treatment plants, many rely on off-grid options like pit latrines and septic tanks, which are hard to empty and often lead to illegal waste dumping; this research focuses on container-based sanitation (CBS) as an emerging off-grid solution. Off-grid sanitation refers to waste management systems that operate independently of centralized infrastructure and CBS is a service providing toilets that collect human waste in sealable containers, which are regularly emptied and safely disposed of. These data relate to a project investigating CBS in Kenya, Peru, and South Africa, focusing on how different user groups access and utilize sanitation - contrasting CBS with other types. Participants, acting as citizen scientists, collected confidential data through a dedicated smartphone app designed by the authors and external contractors. This project aimed to explore the effective scaling, management, and regulation of off-grid sanitation systems, relevant to academics in urban planning, water and sanitation services, institutional capability, policy and governance, and those addressing inequality and poverty reduction. The 12-month data collection period offered participants small incentives for weekly engagement, in a micro payment for micro tasks approach. Participants were randomly selected, attended a training workshop, and (where needed) were given a smartphone which they could keep at the end of the project. We conducted weekly smartphone surveys in over 300 households across informal settlements. These surveys aimed to understand human-environment interactions by capturing daily life, wellbeing, income, infrastructural service use, and socioeconomic variables at a weekly resolution, contributing to more informed analyses and decision-making. The smartphone-based approach offers efficient, cost-effective, and flexible data collection, enabling extensive geographical coverage, broad subject areas, and frequent engagement. The Open Data Kit (ODK) tools were used to support data collection in the resource-constrained environment with limited or intermittent connectivity.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38997095

RESUMO

PURPOSE: Homologous recombination deficient (HRD) tumors are exquisitely sensitive to platinum-based chemotherapy and when combined with radiation therapy (RT), leads to improved overall survival in multiple cancer types. Whether a subset of tumors with distinct molecular characteristics demonstrate increased benefit from cisplatin and RT (c-RT) is unclear. We hypothesized that HRD tumors, whether associated with BRCA mutations or genomic scars of HRD, exhibit exquisite sensitivity to c-RT, and that HRD may be a significant driver of c-RT benefit. METHODS AND MATERIALS: Sensitivity to c-RT was examined using isogenic and sporadic breast cancer cell lines. HRD was assessed using 4 assays: RT-induced Rad51 foci, a DR-GFP reporter assay, a genomic scar score (large-scale state transitions [LST]), and clonogenic survival assays. Whole-genome sequencing of 4 breast tumors from a phase 2 clinical trial of neoadjuvant c-RT in triple-negative breast cancer was performed and HRD was defined using HRDetect. RESULTS: BRCA1/2 deficient cell lines displayed functional HRD based on the Rad51 functional assay, with c-RT to RT or cisplatin interaction ratios (IR) of 1.11 and 26.84 for the BRCA1 isogenic pair at 2 µM cisplatin and 6 Gy, respectively. The highest LST lines demonstrated HRD and synthetic cytotoxicity to c-RT with IR at 2 Gy and cisplatin 20 µM of 7.50, and the lowest LST line with IR of 0.65. Of 4 evaluable patients in the phase 2 trial, one achieved a pathologic complete response with corresponding HRD based on multiple genomic scar scores including HRDetect and LST scores, compared with patients without a pathologic complete response. CONCLUSIONS: HRD breast cancers, whether identified by BRCA1/2 mutation status, functional tests, or mutational signatures, appear to be significantly more sensitive to c-RT compared with isogenic controls or tumors without HRD mutational signatures. HRD tumors may be exquisitely sensitive to c-RT which warrants further clinical investigation to guide a precision oncology approach.

7.
JAMA Psychiatry ; 81(9): 889-901, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38888899

RESUMO

Importance: Observational studies suggest that major psychiatric disorders and substance use behaviors reduce longevity, making it difficult to disentangle their relationships with aging-related outcomes. Objective: To evaluate the associations between the genetic liabilities for major psychiatric disorders, substance use behaviors (smoking and alcohol consumption), and longevity. Design, Settings, and Participants: This 2-sample mendelian randomization (MR) study assessed associations between psychiatric disorders, substance use behaviors, and longevity using single-variable and multivariable models. Multiomics analyses were performed elucidating transcriptomic underpinnings of the MR associations and identifying potential proteomic therapeutic targets. This study sourced summary-level genome-wide association study (GWAS) data, gene expression, and proteomic data from cohorts of European ancestry. Analyses were performed from May 2022 to November 2023. Exposures: Genetic susceptibility for major depression (n = 500 199), bipolar disorder (n = 413 466), schizophrenia (n = 127 906), problematic alcohol use (n = 435 563), weekly alcohol consumption (n = 666 978), and lifetime smoking index (n = 462 690). Main Outcomes and Measures: The main outcome encompassed aspects of health span, lifespan, and exceptional longevity. Additional outcomes were epigenetic age acceleration (EAA) clocks. Results: Findings from multivariable MR models simultaneously assessing psychiatric disorders and substance use behaviorsm suggest a negative association between smoking and longevity in cohorts of European ancestry (n = 709 709; 431 503 [60.8%] female; ß, -0.33; 95% CI, -0.38 to -0.28; P = 4.59 × 10-34) and with increased EAA (n = 34 449; 18 017 [52.3%] female; eg, PhenoAge: ß, 1.76; 95% CI, 0.72 to 2.79; P = 8.83 × 10-4). Transcriptomic imputation and colocalization identified 249 genes associated with smoking, including 36 novel genes not captured by the original smoking GWAS. Enriched pathways included chromatin remodeling and telomere assembly and maintenance. The transcriptome-wide signature of smoking was inversely associated with longevity, and estimates of individual smoking-associated genes, eg, XRCC3 and PRMT6, aligned with the smoking-longevity MR analyses, suggesting underlying transcriptomic mediators. Cis-instrument MR prioritized brain proteins associated with smoking behavior, including LY6H (ß, 0.02; 95% CI, 0.01 to 0.03; P = 2.37 × 10-6) and RIT2 (ß, 0.02; 95% CI, 0.01 to 0.03; P = 1.05 × 10-5), which had favorable adverse-effect profiles across 367 traits evaluated in phenome-wide MR. Conclusions: The findings suggest that the genetic liability of smoking, but not of psychiatric disorders, is associated with longevity. Transcriptomic associations offer insights into smoking-related pathways, and identified proteomic targets may inform therapeutic development for smoking cessation strategies.


Assuntos
Estudo de Associação Genômica Ampla , Longevidade , Análise da Randomização Mendeliana , Humanos , Longevidade/genética , Feminino , Masculino , Fumar/epidemiologia , Fumar/genética , Transtornos Relacionados ao Uso de Substâncias/genética , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/epidemiologia , Predisposição Genética para Doença/genética , Esquizofrenia/genética , Esquizofrenia/epidemiologia , Transtornos Mentais/genética , Transtornos Mentais/epidemiologia , Transtorno Bipolar/genética , Transtorno Bipolar/epidemiologia , Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/epidemiologia , Idoso , Pessoa de Meia-Idade
8.
Lancet Microbe ; 5(9): 100885, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38906163

RESUMO

BACKGROUND: High proportions of Mycobacterium tuberculosis cells in sputum containing triacylglycerol-rich lipid bodies have been shown to be associated with treatment failure or relapse following antituberculous chemotherapy. Although lipid body determination is a potential biomarker for supporting clinical trial and treatment decisions, factors influencing variability in sputum frequencies of lipid body-positive (%LB+) M tuberculosis in patients are unknown. We aimed to test our hypothesis that exposure to host-generated NO and M tuberculosis strains are factors associated with differences in sputum %LB+. METHODS: In this observational study, we determined %LB+ frequencies before treatment by microscopy in patients with smear-positive tuberculosis from two separate prospective observational study settings (Gondar, Ethiopia, recruited between May 1, 2010, and April 30, 2011, and Fajara, The Gambia, who provided sputum samples before treatment between May 5, 2010, and Dec 22, 2011). In Ethiopia, fractional exhaled nitric oxide (FeNO) was measured as a biomarker of host NO, and M tuberculosis strain differences were determined by spoligotyping. Treatment response was assessed by percentage weight change after 7 months. In The Gambia, treatment responses were assessed as change in BMI and radiographic burden of disease after 6 months. Sputum M tuberculosis isolates were studied in vitro for their %LB+ and triacylglycerol synthase 1 (tgs1) mRNA responses to NO exposure. Propidium iodide staining was used as a measure of NO strain toxicity. Correlation between in vitro %LB+ frequencies following NO exposure and those of the same strain in sputum was examined with linear regression and Dunnett's multiple comparison test. FINDINGS: In Ethiopia, 73 patients who were smear positive for pulmonary tuberculosis were recruited (43 [59%] were male and 30 [41%] were female). Of these, the %LB+ in the sputum of 59 patients showed linear correlation with log10 FeNO (r2=0·28; p<0·0001) and an association with strain spoligotype was suggested. Seven M tuberculosis strains from The Gambia showed different dose-responses to NO in vitro, demonstrated by changing lipid body content, tgs1 transcription, and bacterial toxicity. In sputum %LB+ frequencies correlated with in vitro %LB+ responses to NO of the corresponding isolate. In a subset of 34 patients across both cohorts, higher sputum %LB+ frequencies before treatment were associated with weaker responses to treatment than lower sputum %LB+ frequencies. INTERPRETATION: M tuberculosis strain and exposure to host-generated NO are associated with sputum %LB+. Our results support the use of M tuberculosis strain-dependent sputum %LB+ as a predictive biomarker of treatment response. FUNDING: The Medical Research Council, the University of Leicester, and the University of Gondar.


Assuntos
Gotículas Lipídicas , Mycobacterium tuberculosis , Escarro , Tuberculose Pulmonar , Humanos , Escarro/microbiologia , Masculino , Gâmbia , Feminino , Adulto , Estudos Prospectivos , Etiópia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/metabolismo , Gotículas Lipídicas/metabolismo , Pessoa de Meia-Idade , Antituberculosos/uso terapêutico , Antituberculosos/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico/análise , Adulto Jovem , Tuberculose/microbiologia , Tuberculose/tratamento farmacológico , Tuberculose/metabolismo , Interações Hospedeiro-Patógeno
9.
Accid Anal Prev ; 204: 107646, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38830295

RESUMO

Paramedics face various unconventional and secondary task demands while driving ambulances, leading to significant cognitive load, especially during lights-and-sirens responses. Previous research suggests that high cognitive load negatively affects driving performance, increasing the risk of accidents, particularly for inexperienced drivers. The current study investigated the impact of anticipatory treatment planning on cognitive load during emergency driving, as assessed through the use of a driving simulator. We recruited 28 non-paramedic participants to complete a simulated baseline drive with no task and a cognitive load manipulation using the 1-back task. We also recruited 18 paramedicine students who completed a drive while considering two cases they were travelling to: cardiac arrest and infant seizure, representing varying difficulty in required treatment. The results indicated that both cases imposed considerable cognitive load, as indicated by NASA Task Load Index responses, comparable to the 1-back task and significantly higher than driving with no load. These findings suggest that contemplating cases and treatment plans may impact the safety of novice paramedics driving ambulances for emergency response. Further research should explore the influence of experience and the presence of a second individual in the vehicle to generalise to broader emergency response driving contexts.


Assuntos
Condução de Veículo , Cognição , Humanos , Masculino , Feminino , Condução de Veículo/psicologia , Adulto , Adulto Jovem , Convulsões/psicologia , Simulação por Computador , Pessoal Técnico de Saúde/educação , Pessoal Técnico de Saúde/psicologia , Ambulâncias , Lactente , Tratamento de Emergência , Análise e Desempenho de Tarefas , Paramedicina
10.
J Assoc Res Otolaryngol ; 25(4): 313-328, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38710871

RESUMO

When David Kemp discovered "spontaneous ear noise" in 1978, it opened up a whole new perspective on how the cochlea works. The continuous tonal sound emerging from most healthy human ears, now called spontaneous otoacoustic emissions or SOAEs, was an unmistakable sign that our hearing organ must be considered an active detector, not just a passive microphone, just as Thomas Gold had speculated some 30 years earlier. Clearly, something is oscillating as a byproduct of that sensitive inbuilt detector, but what exactly is it? Here, we give a chronological account of efforts to model SOAEs as some form of oscillator, and at intervals, we illustrate key concepts with numerical simulations. We find that after many decades there is still no consensus, and the debate extends to whether the oscillator is local, confined to discrete local sources on the basilar membrane, or global, in which an assembly of micro-mechanical elements and basilar membrane sections, coupled by inner ear fluid, interact over a wide region. It is also undecided whether the cochlear oscillator is best described in terms of the well-known Van der Pol oscillator or the less familiar Duffing or Hopf oscillators. We find that irregularities play a key role in generating the emissions. This paper is not a systematic review of SOAEs and their properties but more a historical survey of the way in which various oscillator configurations have been applied to modelling human ears. The conclusion is that the difference between the local and global approaches is not clear-cut, and they are probably not mutually exclusive concepts. Nevertheless, when one sees how closely human SOAEs can be matched to certain arrangements of oscillators, Gold would no doubt say we are on the right track.


Assuntos
Emissões Otoacústicas Espontâneas , Humanos , Emissões Otoacústicas Espontâneas/fisiologia , Modelos Biológicos
12.
Soc Sci Med ; 350: 116898, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705077

RESUMO

Intersectional Multilevel Analysis of Individual Heterogeneity and Discriminatory Accuracy (MAIHDA) has been welcomed as a new gold standard for quantitative evaluation of intersectional inequalities, and it is being rapidly adopted across the health and social sciences. In their commentary "What does the MAIHDA method explain?", Wilkes and Karimi (2024) raise methodological concerns with this approach, leading them to advocate for the continued use of conventional single-level linear regression models with fixed-effects interaction parameters for quantitative intersectional analysis. In this response, we systematically address these concerns, and ultimately find them to be unfounded, arising from a series of subtle but important misunderstandings of the MAIHDA approach and literature. Since readers new to MAIHDA may share confusion on these points, we take this opportunity to provide clarifications. Our response is organized around four important clarifications: (1) At what level are the additive main effect variables defined in intersectional MAIHDA models? (2) Do MAIHDA models have problems with collinearity? (3) Why does the Variance Partitioning Coefficient (VPC) tend to be small, and the Proportional Change in Variance (PCV) tend to be large in MAIHDA? and (4) What are the goals of MAIHDA analysis?


Assuntos
Análise Multinível , Humanos , Fatores Socioeconômicos , Disparidades nos Níveis de Saúde
13.
Soc Sci Med ; 351: 116955, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38762996

RESUMO

The intersectional Multilevel Analysis of Individual Heterogeneity and Discriminatory Accuracy (MAIHDA) approach is gaining prominence in health sciences and beyond, as a robust quantitative method for identifying intersectional inequalities in a range of individual outcomes. However, it has so far not been applied to longitudinal data, despite the availability of such data, and growing recognition that intersectional social processes and determinants are not static, unchanging phenomena. Drawing on intersectionality and life course theories, we develop a longitudinal version of the intersectional MAIHDA approach, allowing the analysis not just of intersectional inequalities in static individual differences, but also of life course trajectories. We discuss the conceptualization of intersectional groups in this context: how they are changeable over the life course, appropriate treatment of generational differences, and relevance of the age-period-cohort identification problem. We illustrate the approach with a study of mental health using United Kingdom Household Longitudinal Study data (2009-2021). The results reveal important differences in trajectories between generations and intersectional strata, and show that trajectories are partly multiplicative but mostly additive in their intersectional inequalities. This article provides an important and much needed methodological contribution, enabling rigorous quantitative, longitudinal, intersectional analyses in social epidemiology and beyond.


Assuntos
Saúde Mental , Análise Multinível , Humanos , Estudos Longitudinais , Reino Unido , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Fatores Socioeconômicos , Disparidades nos Níveis de Saúde , Adolescente
14.
SSM Popul Health ; 26: 101664, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38690117

RESUMO

Intersectional multilevel analysis of individual heterogeneity and discriminatory accuracy (I-MAIHDA) is an innovative approach for investigating inequalities, including intersectional inequalities in health, disease, psychosocial, socioeconomic, and other outcomes. I-MAIHDA and related MAIHDA approaches have conceptual and methodological advantages over conventional single-level regression analysis. By enabling the study of inequalities produced by numerous interlocking systems of marginalization and oppression, and by addressing many of the limitations of studying interactions in conventional analyses, intersectional MAIHDA provides a valuable analytical tool in social epidemiology, health psychology, precision medicine and public health, environmental justice, and beyond. The approach allows for estimation of average differences between intersectional strata (stratum inequalities), in-depth exploration of interaction effects, as well as decomposition of the total individual variation (heterogeneity) in individual outcomes within and between strata. Specific advice for conducting and interpreting MAIHDA models has been scattered across a burgeoning literature. We consolidate this knowledge into an accessible conceptual and applied tutorial for studying both continuous and binary individual outcomes. We emphasize I-MAIHDA in our illustration, however this tutorial is also informative for understanding related approaches, such as multicategorical MAIHDA, which has been proposed for use in clinical research and beyond. The tutorial will support readers who wish to perform their own analyses and those interested in expanding their understanding of the approach. To demonstrate the methodology, we provide step-by-step analytical advice and present an illustrative health application using simulated data. We provide the data and syntax to replicate all our analyses.

15.
Proc Natl Acad Sci U S A ; 121(23): e2314213121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805282

RESUMO

The anterolateral system (ALS) is a major ascending pathway from the spinal cord that projects to multiple brain areas and underlies the perception of pain, itch, and skin temperature. Despite its importance, our understanding of this system has been hampered by the considerable functional and molecular diversity of its constituent cells. Here, we use fluorescence-activated cell sorting to isolate ALS neurons belonging to the Phox2a-lineage for single-nucleus RNA sequencing. We reveal five distinct clusters of ALS neurons (ALS1-5) and document their laminar distribution in the spinal cord using in situ hybridization. We identify three clusters of neurons located predominantly in laminae I-III of the dorsal horn (ALS1-3) and two clusters with cell bodies located in deeper laminae (ALS4 and ALS5). Our findings reveal the transcriptional logic that underlies ALS neuronal diversity in the adult mouse and uncover the molecular identity of two previously identified classes of projection neurons. We also show that these molecular signatures can be used to target groups of ALS neurons using retrograde viral tracing. Overall, our findings provide a valuable resource for studying somatosensory biology and targeting subclasses of ALS neurons.


Assuntos
Proteínas de Homeodomínio , Animais , Camundongos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Medula Espinal/citologia , Medula Espinal/metabolismo , Neurônios/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Núcleo Celular/metabolismo , Núcleo Celular/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Brain Behav Immun ; 119: 494-506, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38657842

RESUMO

Alcohol Use Disorder (AUD) is a persistent condition linked to neuroinflammation, neuronal oxidative stress, and neurodegenerative processes. While the inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) has demonstrated effectiveness in reducing liver inflammation associated with alcohol, its impact on the brain remains largely unexplored. This study aimed to assess the effects of alirocumab, a monoclonal antibody targeting PCSK9 to lower systemic low-density lipoprotein cholesterol (LDL-C), on central nervous system (CNS) pathology in a rat model of chronic alcohol exposure. Alirocumab (50 mg/kg) or vehicle was administered weekly for six weeks in 32 male rats subjected to a 35 % ethanol liquid diet or a control liquid diet (n = 8 per group). The study evaluated PCSK9 expression, LDL receptor (LDLR) expression, oxidative stress, and neuroinflammatory markers in brain tissues. Chronic ethanol exposure increased PCSK9 expression in the brain, while alirocumab treatment significantly upregulated neuronal LDLR and reduced oxidative stress in neurons and brain vasculature (3-NT, p22phox). Alirocumab also mitigated ethanol-induced microglia recruitment in the cortex and hippocampus (Iba1). Additionally, alirocumab decreased the expression of pro-inflammatory cytokines and chemokines (TNF, CCL2, CXCL3) in whole brain tissue and attenuated the upregulation of adhesion molecules in brain vasculature (ICAM1, VCAM1, eSelectin). This study presents novel evidence that alirocumab diminishes oxidative stress and modifies neuroimmune interactions in the brain elicited by chronic ethanol exposure. Further investigation is needed to elucidate the mechanisms by which PCSK9 signaling influences the brain in the context of chronic ethanol exposure.


Assuntos
Anticorpos Monoclonais Humanizados , Encéfalo , Etanol , Neurônios , Estresse Oxidativo , Inibidores de PCSK9 , Pró-Proteína Convertase 9 , Animais , Estresse Oxidativo/efeitos dos fármacos , Masculino , Ratos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Inibidores de PCSK9/farmacologia , Pró-Proteína Convertase 9/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Anticorpos Monoclonais Humanizados/farmacologia , Alcoolismo/metabolismo , Alcoolismo/tratamento farmacológico , Microglia/metabolismo , Microglia/efeitos dos fármacos , Receptores de LDL/metabolismo , Ratos Sprague-Dawley , Modelos Animais de Doenças
17.
Microbiology (Reading) ; 170(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38488830

RESUMO

Sialic acid (Sia) transporters are critical to the capacity of host-associated bacteria to utilise Sia for growth and/or cell surface modification. While N-acetyl-neuraminic acid (Neu5Ac)-specific transporters have been studied extensively, little is known on transporters dedicated to anhydro-Sia forms such as 2,7-anhydro-Neu5Ac (2,7-AN) or 2,3-dehydro-2-deoxy-Neu5Ac (Neu5Ac2en). Here, we used a Sia-transport-null strain of Escherichia coli to investigate the function of members of anhydro-Sia transporter families previously identified by computational studies. First, we showed that the transporter NanG, from the Glycoside-Pentoside-Hexuronide:cation symporter family, is a specific 2,7-AN transporter, and identified by mutagenesis a crucial functional residue within the putative substrate-binding site. We then demonstrated that NanX transporters, of the Major Facilitator Superfamily, also only transport 2,7-AN and not Neu5Ac2en nor Neu5Ac. Finally, we provided evidence that SiaX transporters, of the Sodium-Solute Symporter superfamily, are promiscuous Neu5Ac/Neu5Ac2en transporters able to acquire either substrate equally well. The characterisation of anhydro-Sia transporters expands our current understanding of prokaryotic Sia metabolism within host-associated microbial communities.


Assuntos
Ácido N-Acetilneuramínico , Ácido N-Acetilneuramínico/análogos & derivados , Transportadores de Ânions Orgânicos , Simportadores , Ácido N-Acetilneuramínico/química , Simportadores/genética , Simportadores/metabolismo , Bactérias/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
19.
Cell Mol Gastroenterol Hepatol ; 17(1): 29-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37703945

RESUMO

BACKGROUND & AIMS: Observational studies have linked lipid-lowering drug targets pro-protein convertase subtilisin/kexin 9 (PCSK9) and HMG-CoA reductase (HMGCR) with adverse liver outcomes; however, liver disease incidence varies across diverse populations, and the long-term hepatic impact of these lipid-lowering drugs among non-white Europeans remains largely unknown. METHODS: We use single nucleotide polymorphisms (SNPs) in PCSK9 and HMGCR loci from genome-wide association study data of low-density lipoprotein cholesterol in 4 populations (East Asian [EAS], South Asian [SAS], African [AFR], and European [EUR]) to perform drug-target Mendelian randomization investigating relationships between PCSK9 and HMGCR inhibition and alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and bilirubin. RESULTS: Analyses of PCSK9 instruments, including functional variants R46L and E670G, failed to find evidence for relationships of low-density lipoprotein cholesterol lowering via PCSK9 variants and adverse effects on ALT, AST, GGT, or ALP among the cohorts. PCSK9 inhibition was associated with increased direct bilirubin levels in EUR (ß = 0.089; P value = 5.69 × 10-6) and, nominally, in AFR (ß = 0.181; P value = .044). HMGCR inhibition was associated with reduced AST in SAS (ß = -0.705; P value = .005) and, nominally, reduced AST in EAS (ß = -0.096; P value = .03), reduced ALP in EUR (ß = -2.078; P value = .014), and increased direct bilirubin in EUR (ß = 0.071; P value = .032). Sensitivity analyses using genetic instruments derived from circulating PCSK9 protein levels, tissue-specific PCSK9 expression, and HMGCR expression were in alignment, strengthening causal inference. CONCLUSIONS: We did not find ALT, AST, GGT, or ALP associated with genetically proxied PCSK9 and HMGCR inhibition across ancestries. We identified possible relationships in several ancestries between PCSK9 and increased direct and total bilirubin and between HMGCR and reduced AST. These findings support long-term safety profiles and low hepatotoxic risk of PCSK9 and HMGCR inhibition in diverse populations.


Assuntos
Pró-Proteína Convertase 9 , Subtilisina , Humanos , Pró-Proteína Convertase 9/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Fígado , Bilirrubina , Lipoproteínas LDL , Colesterol , Lipídeos , Hidroximetilglutaril-CoA Redutases/genética
20.
Nat Commun ; 14(1): 6614, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857603

RESUMO

Shallow magmatic reservoirs that produce measurable volcanic surface deformation are often considered as discrete independent systems. However, petrological analyses of erupted products suggest that these may be the shallowest expression of extensive, heterogeneous magmatic systems that we show may be interconnected. We analyse time series of satellite-radar-measured displacements at Western Galápagos volcanoes from 2017 to 2022 and revisit historical displacements. We demonstrate that these volcanoes consistently experience correlated displacements during periods of heightened magma supply to the shallow crust. We rule out changes in static stress, shallow hydraulic connections, and data processing and analysis artefacts. We propose that episodic surges of magma into interconnected magmatic systems affect neighbouring volcanoes, simultaneously causing correlations in volcanic uplift and subsidence. While expected to occur globally, such processes are uniquely observable at the dense cluster of Western Galápagos volcanoes, thanks to the high rate of surface displacements and the wealth of geodetic measurements.

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