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1.
Mol Oncol ; 18(2): 245-279, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38135904

RESUMEN

Analyses of inequalities related to prevention and cancer therapeutics/care show disparities between countries with different economic standing, and within countries with high Gross Domestic Product. The development of basic technological and biological research provides clinical and prevention opportunities that make their implementation into healthcare systems more complex, mainly due to the growth of Personalized/Precision Cancer Medicine (PCM). Initiatives like the USA-Cancer Moonshot and the EU-Mission on Cancer and Europe's Beating Cancer Plan are initiated to boost cancer prevention and therapeutics/care innovation and to mitigate present inequalities. The conference organized by the Pontifical Academy of Sciences in collaboration with the European Academy of Cancer Sciences discussed the inequality problem, dependent on the economic status of a country, the increasing demands for infrastructure supportive of innovative research and its implementation in healthcare and prevention programs. Establishing translational research defined as a coherent cancer research continuum is still a challenge. Research has to cover the entire continuum from basic to outcomes research for clinical and prevention modalities. Comprehensive Cancer Centres (CCCs) are of critical importance for integrating research innovations to preclinical and clinical research, as for ensuring state-of-the-art patient care within healthcare systems. International collaborative networks between CCCs are necessary to reach the critical mass of infrastructures and patients for PCM research, and for introducing prevention modalities and new treatments effectively. Outcomes and health economics research are required to assess the cost-effectiveness of new interventions, currently a missing element in the research portfolio. Data sharing and critical mass are essential for innovative research to develop PCM. Despite advances in cancer research, cancer incidence and prevalence is growing. Making cancer research infrastructures accessible for all patients, considering the increasing inequalities, requires science policy actions incentivizing research aimed at prevention and cancer therapeutics/care with an increased focus on patients' needs and cost-effective healthcare.


Asunto(s)
Neoplasias , Humanos , Ciudad del Vaticano , Neoplasias/prevención & control , Investigación Biomédica Traslacional , Atención a la Salud , Medicina de Precisión
2.
J Biol Chem ; 299(12): 105369, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37865311

RESUMEN

Cardiac MyBP-C (cMyBP-C) interacts with actin and myosin to fine-tune cardiac muscle contractility. Phosphorylation of cMyBP-C, which reduces the binding of cMyBP-C to actin and myosin, is often decreased in patients with heart failure (HF) and is cardioprotective in model systems of HF. Therefore, cMyBP-C is a potential target for HF drugs that mimic its phosphorylation and/or perturb its interactions with actin or myosin. We labeled actin with fluorescein-5-maleimide (FMAL) and the C0-C2 fragment of cMyBP-C (cC0-C2) with tetramethylrhodamine (TMR). We performed two complementary high-throughput screens (HTS) on an FDA-approved drug library, to discover small molecules that specifically bind to cMyBP-C and affect its interactions with actin or myosin, using fluorescence lifetime (FLT) detection. We first excited FMAL and detected its FLT, to measure changes in fluorescence resonance energy transfer (FRET) from FMAL (donor) to TMR (acceptor), indicating binding. Using the same samples, we then excited TMR directly, using a longer wavelength laser, to detect the effects of compounds on the environmentally sensitive FLT of TMR, to identify compounds that bind directly to cC0-C2. Secondary assays, performed on selected modulators with the most promising effects in the primary HTS assays, characterized the specificity of these compounds for phosphorylated versus unphosphorylated cC0-C2 and for cC0-C2 versus C1-C2 of fast skeletal muscle (fC1-C2). A subset of identified compounds modulated ATPase activity in cardiac and/or skeletal myofibrils. These assays establish the feasibility of the discovery of small-molecule modulators of the cMyBP-C-actin/myosin interaction, with the ultimate goal of developing therapies for HF.


Asunto(s)
Proteínas Portadoras , Descubrimiento de Drogas , Insuficiencia Cardíaca , Miofibrillas , Bibliotecas de Moléculas Pequeñas , Humanos , Actinas/metabolismo , Descubrimiento de Drogas/métodos , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/metabolismo , Miocardio/metabolismo , Miosinas/metabolismo , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Evaluación Preclínica de Medicamentos , Miofibrillas/efectos de los fármacos , Proteínas Portadoras/metabolismo , Técnicas Biosensibles , Adenosina Trifosfatasas/metabolismo , Músculo Esquelético/metabolismo , Proteínas Recombinantes/metabolismo , Activación Enzimática/efectos de los fármacos , Transferencia Resonante de Energía de Fluorescencia
3.
Nat Prod Commun ; 18(1)2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37063699

RESUMEN

Death receptor 5 (DR5) is an apoptosis-inducing membrane receptor that mediates cell death in several life-threatening conditions. There is a crucial need for the discovery of DR5 antagonists for the therapeutic intervention of conditions in which the overactivation of DR5 underlies the pathophysiology. DR5 activation mediates cell death in non-alcoholic fatty liver disease (NAFLD) and neurodegenerative processes including amyloid-beta (Aß) accumulation, spinal cord injury (SCI), and brain ischemia. In the current work, we used fluorescence resonance energy transfer (FRET) to monitor the conformational dynamics of DR5 that mediate death signaling. We used a time-resolved FRET screening platform to screen the Selleck library of 2863 U.S. Food and Drug Administration (FDA)-approved compounds. The high-throughput screen (HTS) identified 13 compounds that modulated the FRET between DR5 monomers beyond 5 median absolute deviations (MADs) from the DMSO controls. Of these 13 compounds, indirubin was identified to specifically inhibit tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced caspase-8 activity without modulating DR5 surface expression or TRAIL binding. Indirubin inhibited Fas-associated death domain (FADD) oligomerization and increased cellular FLICE-inhibitory protein (c-FLIP) expression; both are molecular mechanisms involved in inhibiting the DR5 signaling cascade. This study has elucidated previously unknown properties of indirubin that make it a promising candidate for therapeutic investigation of diseases in which overactivation of DR5 underlies pathology.

4.
BMJ Glob Health ; 7(6)2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35680132

RESUMEN

Australian government planning promotes evidence-based action as the overarching goal to achieving health equality for Aboriginal and Torres Strait Islander populations. However, an inequitable distribution of power and resources in the conduct of evidence-based practice produces a policy environment counterintuitive to this goal. This context of contemporary evidence-based practice gives legitimacy to 'expert practitioners' located in Australian governments and universities to use Western guidelines and tools, embedded in Western methodology, to make 'evidence' informed policy and programming decisions about Aboriginal and Torres Strait Islander populations. This method for decision making assumes a positional superiority that can marginalise the important perspectives, experiences and knowledge of Aboriginal Community Controlled Organisations and their processes for decision making. Here we consider the four steps of an evidence review: (1) developing a review question; (2) acquiring studies; (3) appraising the evidence and (4) assessing the evidence, as components of wider evidence-based practice. We discuss some of the limitations across each step that arise from the broader context within which the evidence review is produced. We propose that an ethical and just approach to evidence-based review can be achieved through a well-resourced Aboriginal community controlled sector, where Aboriginal organisations generate their own evidence and evidence is reviewed using methods and tools that privilege Aboriginal and Torres Strait Islander ways of knowing, doing and being.


Asunto(s)
Práctica Clínica Basada en la Evidencia , Nativos de Hawái y Otras Islas del Pacífico , Australia , Humanos , Proyectos de Investigación
5.
Microbiol Spectr ; 10(2): e0010022, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35412372

RESUMEN

Fungal infections are a global threat, but treatments are limited due to a paucity in antifungal drug targets and the emergence of drug-resistant fungi such as Candida auris. Metabolic adaptations enable microbial growth in nutrient-scarce host niches, and they further control immune responses to pathogens, thereby offering opportunities for therapeutic targeting. Because it is a relatively new pathogen, little is known about the metabolic requirements for C. auris growth and its adaptations to counter host defenses. Here, we establish that triggering metabolic dysfunction is a promising strategy against C. auris. Treatment with pyrvinium pamoate (PP) induced metabolic reprogramming and mitochondrial dysfunction evident in disrupted mitochondrial morphology and reduced tricarboxylic acid (TCA) cycle enzyme activity. PP also induced changes consistent with disrupted iron homeostasis. Nutrient supplementation experiments support the proposition that PP-induced metabolic dysfunction is driven by disrupted iron homeostasis, which compromises carbon and lipid metabolism and mitochondria. PP inhibited C. auris replication in macrophages, which is a relevant host niche for this yeast pathogen. We propose that PP causes a multipronged metabolic hit to C. auris: it restricts the micronutrient iron to potentiate nutritional immunity imposed by immune cells, and it further causes metabolic dysfunction that compromises the utilization of macronutrients, thereby curbing the metabolic plasticity needed for growth in host environments. Our study offers a new avenue for therapeutic development against drug-resistant C. auris, shows how complex metabolic dysfunction can be caused by a single compound triggering antifungal inhibition, and provides insights into the metabolic needs of C. auris in immune cell environments. IMPORTANCE Over the last decade, Candida auris has emerged as a human pathogen around the world causing life-threatening infections with wide-spread antifungal drug resistance, including pandrug resistance in some cases. In this study, we addressed the mechanism of action of the antiparasitic drug pyrvinium pamoate against C. auris and show how metabolism could be inhibited to curb C. auris proliferation. We show that pyrvinium pamoate triggers sweeping metabolic and mitochondrial changes and disrupts iron homeostasis. PP-induced metabolic dysfunction compromises the utilization of both micro- and macronutrients by C. auris and reduces its growth in vitro and in immune phagocytes. Our findings provide insights into the metabolic requirements for C. auris growth and define the mechanisms of action of pyrvinium pamoate against C. auris, demonstrating how this compound works by inhibiting the metabolic flexibility of the pathogen. As such, our study characterizes credible avenues for new antifungal approaches against C. auris.


Asunto(s)
Antifúngicos , Candida , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida auris , Homeostasis , Humanos , Hierro , Pruebas de Sensibilidad Microbiana , Mitocondrias
6.
J Mol Cell Cardiol ; 168: 13-23, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35405106

RESUMEN

A key therapeutic target for heart failure and arrhythmia is the deleterious leak through sarcoplasmic reticulum (SR) ryanodine receptor 2 (RyR2) calcium release channels. We have previously developed methods to detect the pathologically leaky state of RyR2 in adult cardiomyocytes by monitoring RyR2 binding to either calmodulin (CaM) or a biosensor peptide (DPc10). Here, we test whether these complementary binding measurements are effective as high-throughput screening (HTS) assays to discover small molecules that target leaky RyR2. Using FRET, we developed and validated HTS procedures under conditions that mimic a pathological state, to screen the library of 1280 pharmaceutically active compounds (LOPAC) for modulators of RyR2 in cardiac SR membrane preparations. Complementary FRET assays with acceptor-labeled CaM and DPc10 were used for Hit prioritization based on the opposing binding properties of CaM vs. DPc10. This approach narrowed the Hit list to one compound, Ro 90-7501, which altered FRET to suggest increased RyR2-CaM binding and decreased DPc10 binding. Follow-up studies revealed that Ro 90-7501 does not detrimentally affect myocyte Ca2+ transients. Moreover, Ro 90-7501 partially inhibits overall Ca2+ leak, as assessed by Ca2+ sparks in permeabilized rat cardiomyocytes. Together, these results demonstrate (1) the effectiveness of our HTS approach where two complementary assays synergize for Hit ranking and (2) a drug discovery process that combines high-throughput, high-precision in vitro structural assays with in situ myocyte assays of the pathologic RyR2 leak. These provide a drug discovery platform compatible with large-scale HTS campaigns, to identify agents that inhibit RyR2 for therapeutic development.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Canal Liberador de Calcio Receptor de Rianodina , Animales , Calcio/metabolismo , Calmodulina/metabolismo , Descubrimiento de Drogas , Transferencia Resonante de Energía de Fluorescencia/métodos , Miocitos Cardíacos/metabolismo , Ratas , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , Proteínas de Unión a Tacrolimus/metabolismo
7.
Brain ; 145(1): 263-275, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-34289020

RESUMEN

Wilson's disease is an autosomal-recessive disorder of copper metabolism with neurological and hepatic presentations. Chelation therapy is used to 'de-copper' patients but neurological outcomes remain unpredictable. A range of neuroimaging abnormalities have been described and may provide insights into disease mechanisms, in addition to prognostic and monitoring biomarkers. Previous quantitative MRI analyses have focused on specific sequences or regions of interest, often stratifying chronically treated patients according to persisting symptoms as opposed to initial presentation. In this cross-sectional study, we performed a combination of unbiased, whole-brain analyses on T1-weighted, fluid-attenuated inversion recovery, diffusion-weighted and susceptibility-weighted imaging data from 40 prospectively recruited patients with Wilson's disease (age range 16-68). We compared patients with neurological (n = 23) and hepatic (n = 17) presentations to determine the neuroradiological sequelae of the initial brain injury. We also subcategorized patients according to recent neurological status, classifying those with neurological presentations or deterioration in the preceding 6 months as having 'active' disease. This allowed us to compare patients with active (n = 5) and stable (n = 35) disease and identify imaging correlates for persistent neurological deficits and copper indices in chronically treated, stable patients. Using a combination of voxel-based morphometry and region-of-interest volumetric analyses, we demonstrate that grey matter volumes are lower in the basal ganglia, thalamus, brainstem, cerebellum, anterior insula and orbitofrontal cortex when comparing patients with neurological and hepatic presentations. In chronically treated, stable patients, the severity of neurological deficits correlated with grey matter volumes in similar, predominantly subcortical regions. In contrast, the severity of neurological deficits did not correlate with the volume of white matter hyperintensities, calculated using an automated lesion segmentation algorithm. Using tract-based spatial statistics, increasing neurological severity in chronically treated patients was associated with decreasing axial diffusivity in white matter tracts whereas increasing serum non-caeruloplasmin-bound ('free') copper and active disease were associated with distinct patterns of increasing mean, axial and radial diffusivity. Whole-brain quantitative susceptibility mapping identified increased iron deposition in the putamen, cingulate and medial frontal cortices of patients with neurological presentations relative to those with hepatic presentations and neurological severity was associated with iron deposition in widespread cortical regions in chronically treated patients. Our data indicate that composite measures of subcortical atrophy provide useful prognostic biomarkers, whereas abnormal mean, axial and radial diffusivity are promising monitoring biomarkers. Finally, deposition of brain iron in response to copper accumulation may directly contribute to neurodegeneration in Wilson's disease.


Asunto(s)
Lesiones Encefálicas , Degeneración Hepatolenticular , Adolescente , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Lesiones Encefálicas/patología , Mapeo Encefálico , Estudios Transversales , Degeneración Hepatolenticular/diagnóstico por imagen , Degeneración Hepatolenticular/patología , Humanos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Neuroimagen , Adulto Joven
8.
Lancet Respir Med ; 9(11): 1275-1287, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34627560

RESUMEN

BACKGROUND: The impact of COVID-19 on physical and mental health and employment after hospitalisation with acute disease is not well understood. The aim of this study was to determine the effects of COVID-19-related hospitalisation on health and employment, to identify factors associated with recovery, and to describe recovery phenotypes. METHODS: The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a multicentre, long-term follow-up study of adults (aged ≥18 years) discharged from hospital in the UK with a clinical diagnosis of COVID-19, involving an assessment between 2 and 7 months after discharge, including detailed recording of symptoms, and physiological and biochemical testing. Multivariable logistic regression was done for the primary outcome of patient-perceived recovery, with age, sex, ethnicity, body-mass index, comorbidities, and severity of acute illness as covariates. A post-hoc cluster analysis of outcomes for breathlessness, fatigue, mental health, cognitive impairment, and physical performance was done using the clustering large applications k-medoids approach. The study is registered on the ISRCTN Registry (ISRCTN10980107). FINDINGS: We report findings for 1077 patients discharged from hospital between March 5 and Nov 30, 2020, who underwent assessment at a median of 5·9 months (IQR 4·9-6·5) after discharge. Participants had a mean age of 58 years (SD 13); 384 (36%) were female, 710 (69%) were of white ethnicity, 288 (27%) had received mechanical ventilation, and 540 (50%) had at least two comorbidities. At follow-up, only 239 (29%) of 830 participants felt fully recovered, 158 (20%) of 806 had a new disability (assessed by the Washington Group Short Set on Functioning), and 124 (19%) of 641 experienced a health-related change in occupation. Factors associated with not recovering were female sex, middle age (40-59 years), two or more comorbidities, and more severe acute illness. The magnitude of the persistent health burden was substantial but only weakly associated with the severity of acute illness. Four clusters were identified with different severities of mental and physical health impairment (n=767): very severe (131 patients, 17%), severe (159, 21%), moderate along with cognitive impairment (127, 17%), and mild (350, 46%). Of the outcomes used in the cluster analysis, all were closely related except for cognitive impairment. Three (3%) of 113 patients in the very severe cluster, nine (7%) of 129 in the severe cluster, 36 (36%) of 99 in the moderate cluster, and 114 (43%) of 267 in the mild cluster reported feeling fully recovered. Persistently elevated serum C-reactive protein was positively associated with cluster severity. INTERPRETATION: We identified factors related to not recovering after hospital admission with COVID-19 at 6 months after discharge (eg, female sex, middle age, two or more comorbidities, and more acute severe illness), and four different recovery phenotypes. The severity of physical and mental health impairments were closely related, whereas cognitive health impairments were independent. In clinical care, a proactive approach is needed across the acute severity spectrum, with interdisciplinary working, wide access to COVID-19 holistic clinical services, and the potential to stratify care. FUNDING: UK Research and Innovation and National Institute for Health Research.


Asunto(s)
COVID-19 , Estado de Salud , Salud Mental , Enfermedad Aguda , Adulto , Anciano , COVID-19/complicaciones , Cognición , Comorbilidad , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reino Unido/epidemiología
9.
NPJ Biofilms Microbiomes ; 7(1): 13, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33547326

RESUMEN

Novel therapeutics designed to target the polymeric matrix of biofilms requires innovative techniques to accurately assess their efficacy. Here, multiple particle tracking (MPT) was developed to characterize the physical and mechanical properties of antimicrobial resistant (AMR) bacterial biofilms and to quantify the effects of antibiotic treatment. Studies employed nanoparticles (NPs) of varying charge and size (40-500 nm) in Pseudomonas aeruginosa PAO1 and methicillin-resistant Staphylococcus aureus (MRSA) biofilms and also in polymyxin B (PMB) treated Escherichia coli biofilms of PMB-sensitive (PMBSens) IR57 and PMB-resistant (PMBR) PN47 strains. NP size-dependent and strain-related differences in the diffusion coefficient values of biofilms were evident between PAO1 and MRSA. Dose-dependent treatment effects induced by PMB in PMBSens E. coli biofilms included increases in diffusion and creep compliance (P < 0.05), not evident in PMB treatment of PMBR E. coli biofilms. Our results highlight the ability of MPT to quantify the diffusion and mechanical effects of antibiotic therapies within the AMR biofilm matrix, offering a valuable tool for the pre-clinical screening of anti-biofilm therapies.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Escherichia coli/fisiología , Staphylococcus aureus Resistente a Meticilina/fisiología , Polimixina B/farmacología , Pseudomonas aeruginosa/fisiología , Imagen Individual de Molécula/métodos , Biopelículas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Farmacorresistencia Bacteriana , Escherichia coli/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Microscopía Confocal , Nanopartículas , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos
10.
mSphere ; 6(1)2021 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-33472983

RESUMEN

Chronic Pseudomonas aeruginosa lung infections in cystic fibrosis (CF) evolve to generate environmentally adapted biofilm communities, leading to increased patient morbidity and mortality. OligoG CF-5/20, a low-molecular-weight inhaled alginate oligomer therapy, is currently in phase IIb/III clinical trials in CF patients. Experimental evolution of P. aeruginosa in response to OligoG CF-5/20 was assessed using a bead biofilm model allowing continuous passage (45 days; ∼245 generations). Mutants isolated after OligoG CF-5/20 treatment typically had a reduced biofilm-forming ability and altered motility profile. Genotypically, OligoG CF-5/20 provided no selective pressure on genomic mutations within morphotypes. Chronic exposure to azithromycin, a commonly prescribed antibiotic in CF patients, with or without OligoG CF-5/20 in the biofilm evolution model also had no effect on rates of resistance acquisition. Interestingly, however, cross-resistance to other antibiotics (e.g., aztreonam) was reduced in the presence of OligoG CF-5/20. Collectively, these findings show no apparent adverse effects from long-term exposure to OligoG CF-5/20, instead resulting in both fewer colonies with multidrug resistance (MDR)-associated phenotypes and improved antibiotic susceptibility of P. aeruginosaIMPORTANCE The emergence of multidrug-resistant (MDR) pathogens within biofilms in the cystic fibrosis lung results in increased morbidity. An inhalation therapy derived from alginate, OligoG CF-5/20, is currently in clinical trials for cystic fibrosis patients. OligoG CF-5/20 has been shown to alter sputum viscoelasticity, disrupt mucin polymer networks, and disrupt MDR pseudomonal biofilms. Long-term exposure to inhaled therapeutics may induce selective evolutionary pressures on bacteria within the lung biofilm. Here, a bead biofilm model with repeated exposure of P. aeruginosa to OligoG CF-5/20 (alone and in combination with azithromycin) was conducted to study these long-term effects and characterize the phenotypic and genotypic adaptations which result. These findings, over 6 weeks, show that long-term use of OligoG CF-5/20 does not lead to extensive mutational changes and may potentially decrease the pathogenicity of the bacterial biofilm and improve the susceptibility of P. aeruginosa to other classes of antibiotics.


Asunto(s)
Adaptación Fisiológica/genética , Alginatos/química , Biopelículas/efectos de los fármacos , Genotipo , Fenotipo , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/genética , Esputo/microbiología , Factores de Tiempo
11.
Biomolecules ; 11(1)2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466399

RESUMEN

Clays attributed to have medicinal properties have been used since prehistoric times and are still used today as complementary medicines, which has given rise to unregulated "bioceutical" clays to treat skin conditions. Recently, clays with antibacterial characteristics have been proposed as alternatives to antibiotics, potentially overcoming modern day antibiotic resistance. Clays with suggested antibacterial properties were examined to establish their effects on common wound-infecting bacteria. Geochemical, microscopical, and toxicological characterization of clay particulates, their suspensions and filtered leachates was performed on THP-1 and HaCaT cell lines. Cytoskeletal toxicity, cell proliferation/viability (MTT assays), and migration (scratch wounds) were further evaluated. Clays were assayed for antibacterial efficacy using minimum inhibitory concentration assays. All clays possessed a mineral content with antibacterial potential; however, clay leachates contained insufficient ions to have any antibacterial effects. All clay leachates displayed toxicity towards THP-1 monocytes, while clay suspensions showed less toxicity, suggesting immunogenicity. Reduced clay cytotoxicity on HaCaTs was shown, as many leachates stimulated wound-healing responses. The "Green" clay exhibited antibacterial effects and only in suspension, which was lost upon neutralization. pH and its interaction with clay particle surface charge is more significant than previously understood to emphasize dangers of unregulated marketing and unsubstantiated bioceutical claims.


Asunto(s)
Arcilla , Salud , Actinas/metabolismo , Antibacterianos/farmacología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HaCaT , Humanos , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Pruebas de Sensibilidad Microbiana , Células THP-1 , Imagen de Lapso de Tiempo , Heridas y Lesiones/microbiología , Heridas y Lesiones/patología
12.
Health Promot J Austr ; 32 Suppl 2: 185-196, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33034057

RESUMEN

ISSUE ADDRESSED: To examine the factors associated with preventing regular smoking among Aboriginal adolescents. METHODS: Cross-sectional analysis of data from 106 Aboriginal adolescents aged 12-17 years, and their caregivers, from four Aboriginal Community Controlled Health Services in urban New South Wales, 2008-2012. The relation of individual, social, environmental and cultural factors to having 'never' smoked tobacco regularly was examined using Poisson regression. RESULTS: Overall, 83% of adolescents had never smoked regularly; 13 reported current and five past smoking. Most lived in smoke-free homes (60%) despite 75% reporting at least one current smoker caregiver. Participants were significantly more likely to have never smoked regularly if they had good mental health (PR = 1.4, 95% CI: 1.1-1.9), their mother as their primary caregiver (1.3, 1.0-1.6), good family relationships (1.2, 1.0-1.5), stable housing (1.3, 1.1-1.7), had never used alcohol (1.8, 1.3-2.4), were not sexually active (3.1, 1.3- 7.2) and had no criminal justice interactions (1.8, 1.2-2.8). CONCLUSIONS: Most participants lived in smoke-free homes and the vast majority had never smoked regularly. Promoting good mental health and strengthening social connections may be protective against smoking as those experiencing less social disruption were more likely to have never smoked regularly. Smoking may be an indicator of psychosocial conditions and a prompt for screening and simultaneous treatment. SO WHAT?: Organisations should be resourced to deliver holistic adolescent health promotion programs. Programs and policies should support positive family relationships and stable housing as this may protect against the uptake of regular smoking.


Asunto(s)
Salud Infantil , Fumar , Adolescente , Niño , Estudios Transversales , Vivienda , Humanos , Nativos de Hawái y Otras Islas del Pacífico
13.
Curr Dev Nutr ; 4(11): nzaa162, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33274306

RESUMEN

BACKGROUND: Data are limited on how feeding knowledge and practices relate to child undernutrition in the highlands of Madagascar. OBJECTIVES: This study assessed maternal knowledge and practices of complementary feeding and their associations with anthropometrics of children aged 6-23 mo in the Vakinankaratra region of Madagascar. METHODS: Knowledge was assessed using WHO recommendations on child feeding, and WHO infant and young child feeding (IYCF) indicators were used to evaluate feeding practices. Child growth was measured as length-for-age, weight-for-age, and weight-for-length z-scores using the 2006 WHO growth standards. A z-score less than -2 was classified as child undernutrition. Logistic regression models were used to determine associations between independent variables and outcomes. Focus group discussions among mothers and in-depth interviews with key informants were conducted; barriers and facilitators of optimal feeding practices were identified using a thematic analysis approach. RESULTS: Maternal knowledge scores regarding child feeding averaged 6.4 of 11. Better knowledge scores were associated with higher odds of appropriate complementary feeding practices before and after covariate adjustments. The proportions of children achieving the minimum dietary diversity (35.8%), minimum acceptable diet (30.2%), and consuming meat, fish, and poultry (14.1%) were low. Only consumption of iron-rich foods was associated with lower odds of underweight (adjusted OR = 0.3; 95% CI: 0.1, 0.7; P < 0.05). None of the IYCF indicators were associated significantly with stunting or wasting. Maternal attitudes about complementary foods, as well as mothers' workload and very low income, were identified as barriers to optimal feeding practices. Maternal perceived benefits of giving appropriate complementary foods as well as their positive relationship with the community health workers were the main facilitators of optimal child feeding. CONCLUSIONS: Integrated nutrition-sensitive interventions addressing these barriers while enhancing the facilitators are critical in promoting better feeding practices in the Vakinankaratra region.

14.
J Biol Chem ; 295(41): 14100-14110, 2020 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-32788211

RESUMEN

Actin's interactions with myosin and other actin-binding proteins are essential for cellular viability in numerous cell types, including muscle. In a previous high-throughput time-resolved FRET (TR-FRET) screen, we identified a class of compounds that bind to actin and affect actomyosin structure and function. For clinical utility, it is highly desirable to identify compounds that affect skeletal and cardiac muscle differently. Because actin is more highly conserved than myosin and most other muscle proteins, most such efforts have not targeted actin. Nevertheless, in the current study, we tested the specificity of the previously discovered actin-binding compounds for effects on skeletal and cardiac α-actins as well as on skeletal and cardiac myofibrils. We found that a majority of these compounds affected the transition of monomeric G-actin to filamentous F-actin, and that several of these effects were different for skeletal and cardiac actin isoforms. We also found that several of these compounds affected ATPase activity differently in skeletal and cardiac myofibrils. We conclude that these structural and biochemical assays can be used to identify actin-binding compounds that differentially affect skeletal and cardiac muscles. The results of this study set the stage for screening of large chemical libraries for discovery of novel compounds that act therapeutically and specifically on cardiac or skeletal muscle.


Asunto(s)
Actinas , Músculo Esquelético/metabolismo , Miocardio/metabolismo , Miofibrillas/metabolismo , Miosinas , Bibliotecas de Moléculas Pequeñas , Actinas/antagonistas & inhibidores , Actinas/química , Actinas/metabolismo , Animales , Bovinos , Evaluación Preclínica de Medicamentos , Transferencia Resonante de Energía de Fluorescencia , Miosinas/química , Miosinas/metabolismo , Conejos
15.
Ecotoxicol Environ Saf ; 201: 110777, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32485493

RESUMEN

Selenium (Se) is a beneficial element to higher plants. Application of Se at low concentrations enhances the antioxidant metabolism reducing the reactive oxygen species (ROS) generated by plant membrane cells. This study aimed to evaluate how the application of Se in the forms sodium selenate and sodium selenite regulates ROS scavenging in field-grown cowpea plants. Seven Se application rates (0; 2.5; 5; 10; 20; 40 and 60 g ha-1) of each of the two Se forms were applied to plants via the soil. Photosynthetic pigments concentration, gas exchange parameters, lipid peroxidation by malondialdehyde (MDA) concentration, hydrogen peroxide concentration, activity of catalase (CAT, EC:1.11.1.6), glutathione reductase (GR, EC:1.6.4.2), ascorbate peroxidase (APX, EC:1.11.1.11) and Se concentration in leaves and grains were evaluated. In general, Se application led to a decrease in chlorophyll a concentration whilst leading to an increase in chlorophyll b, indicating conservation of total chlorophyll concentration. Application of 2.5 g ha-1 of Se as selenate provided a notable increase in total chlorophyll and total carotenoids compared to the other application rates. Selenate and selenite application decreased lipid peroxidation. However, each Se source acted in a different pathway to combat ROS. While selenate showed more potential to increase activity of APX and GR, selenite showed a higher potential to increase CAT activity. The negative correlation between CAT and GR is indicative that both pathways might be activated under distinct circumstances. The more prominent activity of CAT under high rates of selenite resulted in a negative correlation of this enzyme with chlorophyll a and carotenoids. Both selenate and selenite application increased sucrose and total sugars concentration in leaves of cowpea plants. Overall, these results indicate that application of Se in cowpea under field conditions stimulates distinct pathways to scavenge ROS. This could prove beneficial to mitigate oxidative stress during plant development.


Asunto(s)
Especies Reactivas de Oxígeno/metabolismo , Ácido Selénico/toxicidad , Ácido Selenioso/toxicidad , Vigna/efectos de los fármacos , Antioxidantes/metabolismo , Ascorbato Peroxidasas/metabolismo , Catalasa/metabolismo , Clorofila , Clorofila A , Glutatión Reductasa/metabolismo , Fotosíntesis , Hojas de la Planta/metabolismo , Ácido Selénico/metabolismo , Ácido Selenioso/metabolismo , Selenio/metabolismo , Selenito de Sodio , Vigna/metabolismo , Vigna/fisiología
16.
J Viral Hepat ; 27(10): 1022-1031, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32388879

RESUMEN

Liver fibrosis may be assessed noninvasively with transient electrography (TE). Data on the performance of TE for detecting liver fibrosis in sub-Saharan Africa are limited. We evaluated the diagnostic accuracy of TE by performing liver biopsies on persons with liver fibrosis indicated by TE. We enrolled HIV-infected and HIV-uninfected participants with TE scores consistent with at least minimal disease (liver stiffness measurement [LSM]≥7.1 kPa). Biopsies were performed and staged using the Ishak scoring system. A concordant result was defined using accepted thresholds for significant fibrosis by TE (LSM ≥ 9.3 kPa) and liver biopsy (Ishak score ≥ 2). We used modified Poisson regression methods to quantify the univariate and adjusted prevalence risk ratios (PRR) of the association between covariates and the concordance status of TE and liver biopsy in defining the presence of liver fibrosis. Of 131 participants with valid liver biopsy and TE data, only 5 participants (3.8%) had Ishak score ≥ 2 of whom 4 had LSM ≥ 9.3 kPa (sensitivity = 80%); of the 126 (96.2%) with Ishak score < 2, 76 had LSM < 9.3 kPa (specificity = 61%). In multivariable analysis, discordance was associated with female gender (adjPRR = 1.80, 95%CI 1.1-2.9; P = .019), herbal medicine use (adjPRR 1.64, 95% CI = 1.0-2.5; P = .022), exposure to lake or river water (adjPRR 2.05, 95% CI = 1.1-3.7; P = .016), and current smoking (adjPRR 1.72, 95%CI 1.0-2.9; P = .045). These data suggest that TE among rural Ugandans has low specificity for detection of histologically confirmed liver fibrosis. Caution should be exercised when using this tool to confirm significant liver fibrosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Biopsia , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/epidemiología , Cirrosis Hepática/patología , Uganda
17.
J Hepatol ; 72(1): 67-74, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31604081

RESUMEN

BACKGROUND & AIMS: There have been calls to integrate HCV testing into existing services, including harm reduction and HIV prevention and treatment, but there are few empirical trials to date. We evaluated the impact of integrating HCV testing/education into integrated care centers (ICCs) delivering HIV services to people who inject drugs (PWID) across India, using a cluster-randomized trial. METHODS: We compared ICCs with usual care in the PWID stratum (12 sites) of a 22-site cluster-randomized trial. In 6 sites, ICCs delivering HIV testing, harm reduction, other preventive services and linkage to HIV treatment were scaled from opioid agonist therapy centers and operated for 2 years. On-site rapid HCV antibody testing was integrated after 1 year. To assess impact, we conducted baseline and evaluation surveys using respondent-driven sampling (RDS) across the 12 sites (n = 11,993 recruited at baseline; n = 11,721 recruited at evaluation). The primary outcome was population-level self-reported HCV testing history. RESULTS: At evaluation, HCV antibody prevalence ranged from 7.2-76.6%. Across 6 ICCs, 5,263 ICC clients underwent HCV testing, of whom 2,278 were newly diagnosed. At evaluation, PWID in ICC clusters were 4-fold more likely to report being tested for HCV than in usual care clusters, adjusting for baseline testing (adjusted prevalence ratio [aPR] 3.69; 95% CI 1.34-10.2). PWID in ICC clusters were also 7-fold more likely to be aware of their HCV status (aPR 7.11; 95% CI 1.14-44.3) and significantly more likely to initiate treatment (aPR 9.86; 95% CI 1.52-63.8). CONCLUSIONS: We provide among the first empirical data supporting the integration of HCV testing into HIV/harm reduction services. To achieve elimination targets, programs will need to scale-up such venues to deliver comprehensive HCV services. CLINICALTRIALS. GOV IDENTIFIER: NCT01686750. LAY SUMMARY: Delivering hepatitis C virus (HCV) testing to people who inject drugs (PWID) in places where they also have access to HIV prevention and treatment services is an effective way to improve uptake of HCV testing among communities of PWID. To achieve the World Health Organization's ambitious elimination targets, integrated programs will need to be scaled up to deliver comprehensive HCV services.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Prestación Integrada de Atención de Salud/métodos , VIH , Hepacivirus/inmunología , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Infecciones Oportunistas Relacionadas con el SIDA/virología , Adulto , Análisis por Conglomerados , Comorbilidad , Estudios Transversales , Femenino , Reducción del Daño , Hepatitis C/sangre , Hepatitis C/virología , Anticuerpos contra la Hepatitis C/sangre , Humanos , India/epidemiología , Masculino , Prevalencia , Minorías Sexuales y de Género , Adulto Joven
18.
PLoS One ; 14(10): e0223348, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31589645

RESUMEN

Iodine deficiency is one of the major causes of brain damage in childhood. However, iodine supplementation during early pregnancy and lactation can prevent the ill effects of iodine deficiency. This study evaluated maternal and infant thyroid function and infant visual information processing (VIP) in the context of maternal iodine supplementation. A community-based, randomized, supplementation trial was conducted. Mother infant dyads (n = 106) were enrolled within the first 10 days after delivery to participate in this study. Mothers were randomly assigned either to receive a potassium iodide capsule (225 µg iodine) daily for 26 weeks or iodized salt weekly for 26 weeks. Maternal thyroxine (T4), triiodothyronine (T3), thyroid stimulating hormone (TSH), thyroglobulin (Tg), urinary iodine concentration (UIC), breast milk iodine concentration (BMIC) and infant T4, TSH, UIC and VIP were measured as outcome variables. At baseline, neither mothers nor infants in the two groups were significantly different in any of the biomarkers or anthropometric measurements. Maternal TSH and goiter prevalence significantly decreased following iodine supplementation. The percentage of infants who preferentially remembered the familiar face was 26% in the capsule and 51% in the I-salt groups. Infant sex, length for age Z score, BMIC, maternal education and household food security were strong predictors of novelty quotient. In conclusion supplementation daily for six months with an iodine capsule or the use of appropriately iodized salt for an equivalent time was sufficient to reduce goiter and TSH in lactating women. Higher BMIC and LAZ as well as better household food security, maternal education, and male sex predicted higher novelty quotient scores in the VIP paradigm.


Asunto(s)
Desarrollo Infantil/efectos de los fármacos , Lactancia , Yoduro de Potasio/farmacología , Hormonas Tiroideas/sangre , Adulto , Animales , Suplementos Dietéticos , Femenino , Humanos , Recién Nacido , Masculino , Leche/metabolismo , Yoduro de Potasio/administración & dosificación , Hormonas Tiroideas/metabolismo , Percepción Visual
19.
Biophys J ; 117(2): 319-330, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31301803

RESUMEN

We have used high-resolution orientation and distance measurements derived from electron paramagnetic resonance of a bifunctional spin label (BSL) to build and refine atomistic models of protein structure. We demonstrate this approach by investigating the effects of nucleotide binding on the structure of myosin's catalytic domain while myosin is in complex with actin. Constraints for orientation of individual helices were obtained in a previous study from continuous-wave electron paramagnetic resonance of myosin labeled at specific sites with BSLs in oriented muscle fibers. In this study, new distance constraints were derived from double electron-electron resonance on myosin constructs labeled with a BSL specifically at two sites. Using these complementary constraints together, we thoroughly characterize the BSL's rigid, highly stereoselective attachment to protein α-helices, which permits accurate measurements of orientation and distance. We also leverage these measurements to derive a novel, to our knowledge, structural model for myosin-II in complex with actin and MgADP and compare our model to other recent actomyosin structures. The described approach is applicable to any orientable complex (e.g., membranes or filaments) in which site-specific di-Cys mutation is feasible.


Asunto(s)
Simulación de Dinámica Molecular , Marcadores de Spin , Actinas/química , Actomiosina/química , Adenosina Difosfato/química , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Miosina Tipo II/química , Estructura Secundaria de Proteína
20.
Neuroimage ; 199: 418-426, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31185275

RESUMEN

Connectivity-based parcellation of subcortical structures using diffusion tractography is now a common paradigm in neuroscience. These analyses often imply voxel-level specificity of connectivity, and the formation of compact, spatially coherent clusters is often taken as strong imaging-based evidence for anatomically distinct subnuclei in an individual. In this study, we demonstrate that internal structure in diffusion anisotropy is not necessary for a plausible parcellation to be obtained, by spatially permuting diffusion parameters within the thalami and repeating the parcellation. Moreover, we show that, in a winner-takes-all paradigm, most voxels receive the same label before and after this shuffling process-a finding that is stable across image acquisitions and tractography algorithms. We therefore suggest that such parcellations should be interpreted with caution.


Asunto(s)
Imagen de Difusión Tensora/normas , Tálamo/anatomía & histología , Adulto , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Masculino , Tálamo/diagnóstico por imagen
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