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1.
Inorg Chem ; 63(6): 3091-3098, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38295272

RESUMEN

Rechargeable magnesium-ion batteries (MIBs) hold significant promise as an alternative to conventional lithium-ion technology driven by their natural abundance and low-cost, high-energy density, and safety features. Spinel oxides, including MgCrVO4, have emerged as a prospective cathode material for MIBs due to their promising combination of capacity, operating potential, and cation mobility. However, the structural evolution, phase stability, and processes of Mg mobility in MgCrVO4 during electrochemical cycling are poorly understood. In this study, we synthesized a single-phase, solid solution of spinel oxide MgCrVO4 and employed operando X-ray diffraction to couple physical properties with structural changes during cycling. Our results revealed a two-phase reaction mechanism coupled with a solid-solution-like reaction, highlighting the complicated transformation between two distinct phases in the MgCrVO4 lattice during Mg (de)intercalation. Rietveld refinement of the operando data provided valuable insights into the mechanism of the Cr/V-based spinel oxide, shedding light on the transition between the two phases and their roles in Mg-ion (de)intercalation. This study contributes to a deeper understanding of the structural dynamics in multivalent cathode materials and sets the stage for the development of advanced Mg-ion cathodes with enhanced performance and stability.

2.
Phys Chem Chem Phys ; 26(3): 2153-2167, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38131627

RESUMEN

Electroanalytical measurements are routinely used to estimate material properties exhibiting current and voltage signatures. Analysis of such measurements relies on analytical expressions of material properties to describe the experiments. The need for analytical expressions limits the experiments that can be used to measure properties as well as the properties that can be estimated from a given experiment. Such analytical relations are essentially solutions of the physics-based differential equations (with properties as coefficients) describing the material behavior under certain specific conditions. In recent years, a new machine learning-based approach has been gaining popularity wherein the differential equations are numerically solved to interpret the electroanalytical experiments in terms of corresponding material properties. Since the physics-based differential equations are solved, one can additionally estimate underlying fields, e.g., concentration profile, using such an approach. To exemplify the characteristics of such a machine learning assisted interpretation of electroanalytical measurements, we use data from the Hebb-Wagner test on a magnesium spinel intercalation host. As compared to the traditional analytical expression-based interpretation, the emerging approach decreases experimental efforts to characterize relevant material properties as well as provides field information that was previously inaccessible.

3.
J Soc Work End Life Palliat Care ; 19(3): 209-228, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37331000

RESUMEN

The shifting age demographics of those experiencing homelessness in the United States expose shortcomings and barriers within homelessness response services and safety-net healthcare to address serious illness. The purpose of this study is to describe the common trajectories of patients concurrently experiencing homelessness and serious illness. As a part of the Research, Action, and Supportive Care at Later-life for Unhoused People (RASCAL-UP) study, the study uses patient charts (n = 75) from the only specialty palliative care program in the U.S. specifically for people experiencing homelessness. Through a thematic mixed-method analysis, a four-point typology of care pathways taken by people experiencing homelessness while seriously ill is introduced: (1) aging and dying-in-place within the housing care system; (2) frequent transitions during serious illness; (3) healthcare institutions as housing; and (4) housing as palliation. Implications of this exploratory typology include targeted, site-specific interventions for supporting goal-concordant patient care and assisting researchers and policy makers in appreciating heterogeneity in experience and need among older and chronically ill people experiencing homelessness and housing precarity.


Asunto(s)
Enfermería de Cuidados Paliativos al Final de la Vida , Personas con Mala Vivienda , Humanos , Estados Unidos , Vivienda , Cuidados Paliativos
4.
J Gerontol Soc Work ; 66(1): 3-28, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35695062

RESUMEN

Place and health are intricately bound. COVID has amplified system burdens and health risks within the housing care continuum, in which older adults with chronic illnesses are disproportionately represented. The paper identifies the health experiences of older adults with severe conditions living in and moving through temporary avoidance hotels during the COVID-19 pandemic. An interpretive descriptive approach was taken with qualitative chart data and provider observation to represent the experiences of 14 older avoidance hotel residents living with serious illnesses. Through provider documentation, we illustrate trends pre-pandemic, in the first nine months of the pandemic, and the second nine months. Such trends include strengths and opportunities such as the health-affirming nature of avoidance hotels, their potential in generating continuity of care and permanent housing, and synergy between harm reduction approaches and palliative care. Challenges were also identified in catering to the diverse medical, behavioral, and psychosocial-spiritual needs of older and seriously ill residents and the consequences of geographic dispersion on health care, health behaviors, and informal care networks. Through these strengths and challenges, avoidance hotels present essential lessons in considering future housing and healthcare intervention and implementation that addresses the needs of older seriously ill people facing homelessness and housing precarity.


Asunto(s)
COVID-19 , Vivienda , Humanos , Anciano , Pandemias , COVID-19/epidemiología , Atención a la Salud
5.
J Gerontol Soc Work ; 66(6): 739-762, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36617864

RESUMEN

The COVID-19 pandemic caused near immediate service delivery adaptation among social service and healthcare sectors. Findings from in-depth interviews with 45 senior leaders of social services and healthcare organizations serving older adults in Washington State elucidate the role of trust in service provision at the onset of the pandemic. First, a history of trust facilitated service adaptation. Intentional outreach, programs, and culturally responsive services sustained trust with service recipients. Providing services and information in an older adult's preferred language built trust. Community networks facilitated and reflected trust between organizations and older adults. Finally, mistrust was prevalent for clients who perceived a high risk of experiencing negative consequences from accessing services. Our findings support the need for culturally and linguistically diverse services. To improve trust, the aging network should strengthen and expand partnerships with community-based organizations who have established trust through history, intentionality, and relevance to their service populations..


Asunto(s)
COVID-19 , Pandemias , Humanos , Anciano , Accesibilidad a los Servicios de Salud , Confianza , COVID-19/epidemiología , Redes Comunitarias
6.
J Am Chem Soc ; 144(31): 14121-14131, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35895903

RESUMEN

Ion transport in solid-state cathode materials prescribes a fundamental limit to the rates batteries can operate; therefore, an accurate understanding of ion transport is a critical missing piece to enable new battery technologies, such as magnesium batteries. Based on our conventional understanding of lithium-ion materials, MgCr2O4 is a promising magnesium-ion cathode material given its high capacity, high voltage against an Mg anode, and acceptable computed diffusion barriers. Electrochemical examinations of MgCr2O4, however, reveal significant energetic limitations. Motivated by these disparate observations; herein, we examine long-range ion transport by electrically polarizing dense pellets of MgCr2O4. Our conventional understanding of ion transport in battery cathode materials, e.g., Nernst-Einstein conduction, cannot explain the measured response since it neglects frictional interactions between mobile species and their nonideal free energies. We propose an extended theory that incorporates these interactions and reduces to the Nernst-Einstein conduction under dilute conditions. This theory describes the measured response, and we report the first study of long-range ion transport behavior in MgCr2O4. We conclusively show that the Mg chemical diffusivity is comparable to lithium-ion electrode materials, whereas the total conductivity is rate-limiting. Given these differences, energy storage in MgCr2O4 is limited by particle-scale voltage drops, unlike lithium-ion particles that are limited by concentration gradients. Future materials design efforts should consider the interspecies interactions described in this extended theory, particularly with respect to multivalent-ion systems and their resultant effects on continuum transport properties.

7.
J Neurosci Res ; 100(2): 653-669, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34882833

RESUMEN

The role of increased brain inflammation in the development of neurodegenerative diseases is unclear. Here, we have compared cytokine changes in normal aging, motor neurone disease (MND), and Alzheimer's disease (AD). After an initial analysis, six candidate cytokines, interleukin (IL)- 4, 5, 6, 10, macrophage inhibitory protein (MIP)-1α, and fibroblast growth factor (FGF)-2, showing greatest changes were assayed in postmortem frozen human superior frontal gyri (n = 12) of AD patients, aging and young adult controls along with the precentral gyrus (n = 12) of MND patients. Healthy aging was associated with decreased anti-inflammatory IL-10 and FGF-2 levels. AD prefrontal cortex was associated with increased levels of IL-4, IL-5, and FGF-2, with the largest increase seen for FGF-2. Notwithstanding differences in the specific frontal lobe gyrus sampled, MND patients' primary motor cortex (precentral gyrus) was associated with increased levels of IL-5, IL-6, IL-10, and FGF-2 compared to the aging prefrontal cortex (superior frontal gyrus). Immunocytochemistry showed that FGF-2 is expressed in neurons, astrocytes, and microglia in normal aging prefrontal cortex, AD prefrontal cortex, and MND motor cortex. We report that healthy aging and age-related neurodegenerative diseases have different cortical inflammatory signatures that are characterized by increased levels of anti-inflammatory cytokines and call into question the view that increased inflammation underlies the development of age-related neurodegenerative diseases.


Asunto(s)
Envejecimiento , Enfermedad de Alzheimer , Citocinas , Enfermedad de la Neurona Motora , Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Astrocitos/metabolismo , Citocinas/metabolismo , Humanos , Inflamación/metabolismo , Microglía/metabolismo , Enfermedad de la Neurona Motora/metabolismo , Adulto Joven
8.
J Aging Soc Policy ; : 1-26, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36368889

RESUMEN

The COVID-19 pandemic threatened the ability of nutrition providers to address food insufficiency among older adults. Findings from Household Pulse Survey data and interviews with 23 service leaders in Washington state during the summer of 2020 point to key organizational practices that should inform future emergency food assistance planning. Organizations deeply connected to and trusted by racially and ethnically diverse, unhoused, and low-income older adults are critical to addressing disparities in food insufficiency. Stable and flexible increases in funding would allow these organizations to maintain the effective and culturally-relevant service adaptations they implemented in the first months of the pandemic.

9.
Br J Nutr ; 124(4): 374-385, 2020 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-32279690

RESUMEN

There is strong evidence that foods containing dietary fibre protect against colorectal cancer, resulting at least in part from its anti-proliferative properties. This study aimed to investigate the effects of supplementation with two non-digestible carbohydrates, resistant starch (RS) and polydextrose (PD), on crypt cell proliferative state (CCPS) in the macroscopically normal rectal mucosa of healthy individuals. We also investigated relationships between expression of regulators of apoptosis and of the cell cycle on markers of CCPS. Seventy-five healthy participants were supplemented with RS and/or PD or placebo for 50 d in a 2 × 2 factorial design in a randomised, double-blind, placebo-controlled trial (the Dietary Intervention, Stem cells and Colorectal Cancer (DISC) Study). CCPS was assessed, and the expression of regulators of the cell cycle and of apoptosis was measured by quantitative PCR in rectal mucosal biopsies. SCFA concentrations were quantified in faecal samples collected pre- and post-intervention. Supplementation with RS increased the total number of mitotic cells within the crypt by 60 % (P = 0·001) compared with placebo. This effect was limited to older participants (aged ≥50 years). No other differences were observed for the treatments with PD or RS as compared with their respective controls. PD did not influence any of the measured variables. RS, however, increased cell proliferation in the crypts of the macroscopically-normal rectum of older adults. Our findings suggest that the effects of RS on CCPS are not only dose, type of RS and health status-specific but are also influenced by age.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Suplementos Dietéticos , Glucanos/farmacología , Mucosa Intestinal/citología , Recto/citología , Almidón/farmacología , Focos de Criptas Aberrantes/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/metabolismo , Método Doble Ciego , Heces/química , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad
10.
Inorg Chem ; 59(14): 9783-9797, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32633981

RESUMEN

While commercial Li-ion batteries offer the highest energy densities of current rechargeable battery technologies, their energy storage limit has almost been achieved. Therefore, there is considerable interest in Mg batteries, which could offer increased energy densities in comparison to Li-ion batteries if a high-voltage electrode material, such as a transition-metal oxide, can be developed. However, there are currently very few oxide materials which have demonstrated reversible and efficient Mg2+ insertion and extraction at high voltages; this is thought to be due to poor Mg2+ diffusion kinetics within the oxide structural framework. Herein, the authors provide conclusive evidence of electrochemical insertion of Mg2+ into the tetragonal tungsten bronze V4Nb18O55, with a maximum reversible electrochemical capacity of 75 mA h g-1, which corresponds to a magnesiated composition of Mg4V4Nb18O55. Experimental electrochemical magnesiation/demagnesiation revealed a large voltage hysteresis with charge/discharge (1.12 V vs Mg/Mg2+); when magnesiation is limited to a composition of Mg2V4Nb18O55, this hysteresis can be reduced to only 0.5 V. Hybrid-exchange density functional theory (DFT) calculations suggest that a limited number of Mg sites are accessible via low-energy diffusion pathways, but that larger kinetic barriers need to be overcome to access the entire structure. The reversible Mg2+ intercalation involved concurrent V and Nb redox activity and changes in crystal structure, as confirmed by an array of complementary methods, including powder X-ray diffraction, X-ray absorption spectroscopy, and energy-dispersive X-ray spectroscopy. Consequently, it can be concluded that the tetragonal tungsten bronzes show promise as intercalation electrode materials for Mg batteries.

11.
Environ Sci Technol ; 54(4): 2323-2333, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31977201

RESUMEN

Microbially induced concrete corrosion is a major deterioration process in sewers, causing a huge economic burden, and improved mitigating technologies are required. This study reports a novel and promising effective solution to attenuate the corrosion in sewers using calcium nitrite-admixed concrete. This strategy aims to suppress the development and activity of corrosion-inducing microorganisms with the antimicrobial free nitrous acid, which is generated in situ from calcium nitrite that is added to the concrete. Concrete coupons with calcium nitrite as an admixture were exposed in a sewer manhole, together with control coupons that had no nitrite admixture, for 18 months. The corrosion process was monitored by measuring the surface pH, corrosion product composition, concrete corrosion loss, and the microbial community on the corrosion layer. During the exposure, the corrosion loss of the admixed concrete coupons was 30% lower than that of the control coupons. The sulfide uptake rate of the admixed concrete was also 30% lower, leading to a higher surface pH (0.5-0.6 unit), in comparison to that of the control coupons. A negative correlation between the calcium nitrite admixture in concrete and the abundance of sulfide-oxidizing microorganisms was determined by DNA sequencing. The results obtained in this field study demonstrated that this novel use of calcium nitrite as an admixture in concrete is a promising strategy to mitigate the microbially induced corrosion in sewers.


Asunto(s)
Nitritos , Aguas del Alcantarillado , Corrosión , Ácido Nitroso , Sulfuros
12.
Int J Mol Sci ; 21(21)2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33147843

RESUMEN

Space exploration poses multiple challenges for mankind, not only on a technical level but also to the entire physiology of the space traveller. The human system must adapt to several environmental stressors, microgravity being one of them. Lysosomes are ubiquitous to every cell and essential for their homeostasis, playing significant roles in the regulation of autophagy, immunity, and adaptation of the organism to changes in their environment, to name a few. Dysfunction of the lysosomal system leads to age-related diseases, for example bone loss, reduced immune response or cancer. As these conditions have been shown to be accelerated following exposure to microgravity, this review elucidates the lysosomal response to real and simulated microgravity. Microgravity activates the endo-lysosomal system, with resulting impacts on bone loss, muscle atrophy and stem cell differentiation. The investigation of lysosomal adaptation to microgravity can be beneficial in the search for new biomarkers or therapeutic approaches to several disease pathologies on earth as well as the potential to mitigate pathophysiology during spaceflight.


Asunto(s)
Endosomas/fisiología , Lisosomas/fisiología , Simulación de Ingravidez , Ingravidez , Animales , Autofagia , Biomarcadores/metabolismo , Diferenciación Celular , Homeostasis , Humanos , Sistema Inmunológico , Oxígeno/metabolismo , Transducción de Señal , Vuelo Espacial
13.
Br J Nutr ; 122(5): 509-517, 2019 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-30255827

RESUMEN

Bowel cancer risk is strongly influenced by lifestyle factors including diet and physical activity. Several studies have investigated the effects of adherence to the World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) cancer prevention recommendations on outcomes such as all-cause and cancer-specific mortality, but the relationships with molecular mechanisms that underlie the effects on bowel cancer risk are unknown. This study aimed to investigate the relationships between adherence to the WCRF/AICR cancer prevention recommendations and wingless/integrated (WNT)-pathway-related markers of bowel cancer risk, including the expression of WNT pathway genes and regulatory microRNA (miRNA), secreted frizzled-related protein 1 (SFRP1) methylation and colonic crypt proliferative state in colorectal mucosal biopsies. Dietary and lifestyle data from seventy-five healthy participants recruited as part of the DISC Study were used. A scoring system was devised including seven of the cancer prevention recommendations and smoking status. The effects of total adherence score and scores for individual recommendations on the measured outcomes were assessed using Spearman's rank correlation analysis and unpaired t tests, respectively. Total adherence score correlated negatively with expression of Myc proto-oncogene (c-MYC) (P=0·039) and WNT11 (P=0·025), and high adherers had significantly reduced expression of cyclin D1 (CCND1) (P=0·042), WNT11 (P=0·012) and c-MYC (P=0·048). Expression of axis inhibition protein 2 (AXIN2), glycogen synthase kinase (GSK3ß), catenin ß1 (CTNNB1) and WNT11 and of the oncogenic miRNA miR-17 and colonic crypt kinetics correlated significantly with scores for individual recommendations, including body fatness, red meat intake, plant food intake and smoking status. The findings from this study provide evidence for positive effects of adherence to the WCRF/AICR cancer prevention recommendations on WNT-pathway-related markers of bowel cancer risk.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias del Colon/prevención & control , Adhesión a Directriz , Vía de Señalización Wnt , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proto-Oncogenes Mas
14.
Int J Mol Sci ; 20(6)2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30884748

RESUMEN

The QT interval occupies a pivotal role in drug development as a surface biomarker of ventricular repolarization. The electrophysiologic substrate for QT prolongation coupled with reports of non-cardiac drugs producing lethal arrhythmias captured worldwide attention from government regulators eventuating in a series of guidance documents that require virtually all new chemical compounds to undergo rigorous preclinical and clinical testing to profile their QT liability. While prolongation or shortening of the QT interval may herald the appearance of serious cardiac arrhythmias, the positive predictive value of an abnormal QT measurement for these arrhythmias is modest, especially in the absence of confounding clinical features or a congenital predisposition that increases the risk of syncope and sudden death. Consequently, there has been a paradigm shift to assess a compound's cardiac risk of arrhythmias centered on a mechanistic approach to arrhythmogenesis rather than focusing solely on the QT interval. This entails both robust preclinical and clinical assays along with the emergence of concentration QT modeling as a primary analysis tool to determine whether delayed ventricular repolarization is present. The purpose of this review is to provide a comprehensive understanding of the QT interval and highlight its central role in early drug development.


Asunto(s)
Arritmias Cardíacas/tratamiento farmacológico , Arritmias Cardíacas/fisiopatología , Desarrollo de Medicamentos/métodos , Electrocardiografía/métodos , Síndrome de QT Prolongado/tratamiento farmacológico , Síndrome de QT Prolongado/fisiopatología , Animales , Arritmias Cardíacas/diagnóstico , Corazón/efectos de los fármacos , Corazón/fisiopatología , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/fisiopatología , Humanos , Síndrome de QT Prolongado/diagnóstico
15.
Int J Mol Sci ; 20(23)2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31795513

RESUMEN

Syntenin-1 is an essential multi-functional adaptor protein, which has multiple roles in membrane trafficking and exosome biogenesis, as well as scaffolding interactions with either the actin cytoskeleton or focal adhesions. However, how this functional multiplicity relates to syntenin-1 distribution in different endosome compartments or other intracellular locations and its underlying involvement in cancer pathogenesis have yet to be fully defined. To help facilitate the investigation of syntenin-1 biology, we developed two specific monoclonal antibodies (Synt-2C6 and Synt-3A11) to spatially distinct linear sequence epitopes on syntenin-1, which were each designed to be unique at the six-amino acid level. These antibodies produced very different intracellular staining patterns, with Synt-2C6 detecting endosomes and Synt-3A11 producing a fibrillar staining pattern suggesting a cytoskeletal localisation. Treatment of cells with Nocodazole altered the intracellular localisation of Synt-3A11, which was consistent with the syntenin-1 protein interacting with microtubules. In prostate tissue biopsies, Synt-3A11 defined atrophy and early-stage prostate cancer, whereas Synt-2C6 only showed minimal interaction with atrophic tissue. This highlights a critical need for site-specific antibodies and a knowledge of their reactivity to define differential protein distributions, interactions and functions, which may differ between normal and malignant cells.


Asunto(s)
Anticuerpos Monoclonales/análisis , Neoplasias de la Próstata/patología , Sinteninas/análisis , Animales , Línea Celular , Línea Celular Tumoral , Mapeo Epitopo/métodos , Epítopos , Humanos , Inmunoquímica/métodos , Masculino , Modelos Moleculares , Neoplasias de la Próstata/diagnóstico
16.
Phys Chem Chem Phys ; 20(22): 15002-15006, 2018 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-29799043

RESUMEN

A systematic study of the location and energetics of cation dopants in α-V2O5 has been conducted using pair-potential methods, supplemented by first-principles calculations. The consequences of doping on intrinsic defect equilibria have been discussed and the effects of selected dopants on Li+ and Mg2+ diffusion energy barriers have been investigated.

17.
BMC Med Educ ; 18(1): 41, 2018 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-29554966

RESUMEN

BACKGROUND: Like other procedural skills, the ability to relocate a joint is an important aspect of junior doctor education. Changes in the approach to teaching and learning from the traditional apprenticeship-style model have made the teaching of practical skills more difficult logistically. Workshops utilising cadaveric specimens offer a solution to this problem. METHODS: One hundred forty-six fourth year medical students were randomly divided into 5 groups. Each group received a different teaching intervention based on ankle, patella and hip relocation. The interventions consisted of online learning modules, instructional cards and workshops using skeleton models and cadaveric dislocation models. Following the intervention students were given a test containing multiple choice and true/false style questions. A 13-item 5-point Likert scale questionnaire was also delivered before and after the intervention. The data was analysed using one-way analysis of variance (ANOVA) and the Bonferroni post-hoc test. RESULTS: Compared to the instructional cards group, the other 4 groups showed a 10.8-19.2% improvement in total test score (p < 0.01) and an 18.4-25.3% improvement in self-reported understanding and confidence in performing joint relocations (P < 0.01). There was no significant difference in total test scores between groups exposed to cadaveric instruction on the relocation of one-, two- or all three- joints, nor any significant difference between all the cadaveric dislocation groups and the group receiving instruction on the skeleton model. CONCLUSION: The results of the present study suggest that workshops utilising cadaveric dislocation models are effective in teaching joint relocation. In addition, the finding that lower fidelity models may be of equal utility may provide institutions with flexibility of delivery needed to meet financial and resource constraints.


Asunto(s)
Luxaciones Articulares/terapia , Ortopedia/educación , Análisis de Varianza , Traumatismos del Tobillo/terapia , Cadáver , Evaluación Educacional/métodos , Escolaridad , Luxación de la Cadera/terapia , Humanos , Luxación de la Rótula/terapia , Encuestas y Cuestionarios , Enseñanza
18.
Mol Carcinog ; 56(9): 2104-2111, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28418082

RESUMEN

Colorectal cancer (CRC) risk is modulated by diet and there is convincing evidence of reduced risk with higher non-digestible carbohydrates (NDCs) consumption. Resistant starch (RS), a NDC, positively modulates the expression of oncogenic microRNAs, suggesting that this could be a mechanism through which NDCs protect against CRC. The present study aimed to investigate the effects of supplementation with two NDCs, RS, and polydextrose (PD), on microRNA expression in the macroscopically-normal human rectal epithelium using samples from the DISC Study, a randomized, double-blind, placebo-controlled dietary intervention. We screened 1008 miRNAs in pooled post-intervention rectal mucosal samples from participants allocated to the double placebo group and those supplemented with both RS and PD. A total of 111 miRNAs were up- or down-regulated by at least twofold in the RS + PD group compared with the control group. From these, eight were selected for quantification in individual participant samples by qPCR, and fold-change direction was consistent with the array for seven miRNAs. The inconsistency for miR-133b and the lower fold-change values observed for the seven miRNAs is probably because qPCR of individual participant samples is a more robust and sensitive method of quantification than the array. miR-32 expression was increased by approximately threefold (P = 0.033) in the rectal mucosa of participants supplemented with RS + PD compared with placebo. miR-32 is involved in the regulation of processes such as cell proliferation that are dysregulated in CRC. Furthermore, miR-32 may affect non-canonical NF-κB signaling via regulation of TRAF3 expression and consequently NIK stabilization.


Asunto(s)
Colon/efectos de los fármacos , Suplementos Dietéticos , Glucanos/farmacología , Mucosa Intestinal/efectos de los fármacos , MicroARNs/biosíntesis , Recto/efectos de los fármacos , Almidón/farmacología , Adulto , Anciano , Colon/metabolismo , Digestión , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Recto/metabolismo
19.
Br Med Bull ; 121(1): 73-81, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27989995

RESUMEN

Introduction: Meat has been classified by International Agency for Research on Cancer (IARC) as carcinogenic to humans. The evidence and the implications for health are reviewed. Sources of data: Evidence was obtained from published reports and systematic reviews published before and since the IARC decision. Areas of agreement: Epidemiology indicates that processed meat products are associated with increased risk of colorectal cancer. Evidence for red meat and for other cancers remains tentative. Areas of controversy: Several mechanisms for mutagenic effects of meat consumption have been identified but it is not clear which cause cancer in humans. The extent to which complete abstention from meat protects against cancer is also uncertain. Growing points: Prospective studies on meat consumption in western populations will continue to illuminate the details of carcinogenesis, and effective strategies for reducing risk. Areas timely for developing research: Further studies on the precise mechanisms of carcinogenesis in human populations would assist both food manufacturers and the general public to minimize risk.


Asunto(s)
Carcinógenos/análisis , Neoplasias Colorrectales/epidemiología , Dieta/efectos adversos , Productos de la Carne/efectos adversos , Neoplasias Colorrectales/etiología , Dieta Vegetariana , Medicina Basada en la Evidencia , Inocuidad de los Alimentos , Humanos , Vigilancia de la Población , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo
20.
FASEB J ; 30(8): 2812-25, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27103578

RESUMEN

Epidemiologic studies highlight the potential role of dietary selenium (Se) in colorectal cancer prevention. Our goal was to elucidate whether expression of factors crucial for colorectal homoeostasis is affected by physiologic differences in Se status. Using transcriptomics and proteomics followed by pathway analysis, we identified pathways affected by Se status in rectal biopsies from 22 healthy adults, including 11 controls with optimal status (mean plasma Se = 1.43 µM) and 11 subjects with suboptimal status (mean plasma Se = 0.86 µM). We observed that 254 genes and 26 proteins implicated in cancer (80%), immune function and inflammatory response (40%), cell growth and proliferation (70%), cellular movement, and cell death (50%) were differentially expressed between the 2 groups. Expression of 69 genes, including selenoproteins W1 and K, which are genes involved in cytoskeleton remodelling and transcription factor NFκB signaling, correlated significantly with Se status. Integrating proteomics and transcriptomics datasets revealed reduced inflammatory and immune responses and cytoskeleton remodelling in the suboptimal Se status group. This is the first study combining omics technologies to describe the impact of differences in Se status on colorectal expression patterns, revealing that suboptimal Se status could alter inflammatory signaling and cytoskeleton in human rectal mucosa and so influence cancer risk.-Méplan, C., Johnson, I. T., Polley, A. C. J., Cockell, S., Bradburn, D. M., Commane, D. M., Arasaradnam, R. P., Mulholland, F., Zupanic, A., Mathers, J. C., Hesketh, J. Transcriptomics and proteomics show that selenium affects inflammation, cytoskeleton, and cancer pathways in human rectal biopsies.


Asunto(s)
Citoesqueleto/efectos de los fármacos , Inflamación/metabolismo , Neoplasias del Recto/metabolismo , Recto/citología , Selenio/farmacología , Transcriptoma , Adulto , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Proteómica
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