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1.
bioRxiv ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38559204

RESUMEN

Competition over access to resources, such as food and mates, is believed to be one of the major costs associated with group living. Two socioecological factors suggested to predict the intensity of competition are group size and the relative abundance of sexually active individuals. However, empirical evidence linking these factors to injuries and survival costs is scarce. Here, we leveraged 10 years of data from free-ranging rhesus macaques where injuries inflicted by conspecifics are associated with a high mortality risk. We tested if group size and adult sex ratio predicted the occurrence of injuries and used data on physical aggression to contextualise these results. We found that males were less likely to be injured when living in larger groups, potentially due to advantages in intergroup encounters. Females, instead, had higher injury risk when living in larger groups but this was not explained by within-group aggression among females. Further, male-biased sex ratios predicted a weak increase in injury risk in females and were positively related to male-female aggression, indicating that male coercion during mating competition may be a cause of injuries in females. Overall, our results provide insights into sex differences in the fitness-related costs of competition and empirical evidence for long-standing predictions on the evolution of group living.

2.
bioRxiv ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38559098

RESUMEN

The benefits of social living are well established, but sociality also comes with costs, including infectious disease risk. This cost-benefit ratio of sociality is expected to change across individuals' lifespans, which may drive changes in social behaviour with age. To explore this idea, we combine data from a group-living primate for which social ageing has been described with epidemiological models to show that having lower social connectedness when older can protect against the costs of a hypothetical, directly transmitted endemic pathogen. Assuming no age differences in epidemiological characteristics (susceptibility to, severity, and duration of infection), older individuals suffered lower infection costs, which was explained largely because they were less connected in their social networks than younger individuals. This benefit of 'social ageing' depended on epidemiological characteristics and was greatest when infection severity increased with age. When infection duration increased with age, social ageing was beneficial only when pathogen transmissibility was low. Older individuals benefited most from having a lower frequency of interactions (strength) and network embeddedness (closeness) and benefited less from having fewer social partners (degree). Our study provides a first examination of the epidemiology of social ageing, demonstrating the potential for pathogens to influence evolutionary dynamics of social ageing in natural populations.

3.
Geroscience ; 46(2): 2107-2122, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37853187

RESUMEN

Increasing age is associated with dysregulated immune function and increased inflammation-patterns that are also observed in individuals exposed to chronic social adversity. Yet we still know little about how social adversity impacts the immune system and how it might promote age-related diseases. Here, we investigated how immune cell diversity varied with age, sex and social adversity (operationalized as low social status) in free-ranging rhesus macaques. We found age-related signatures of immunosenescence, including lower proportions of CD20 + B cells, CD20 + /CD3 + ratio, and CD4 + /CD8 + T cell ratio - all signs of diminished antibody production. Age was associated with higher proportions of CD3 + /CD8 + Cytotoxic T cells, CD16 + /CD3- Natural Killer cells, CD3 + /CD4 + /CD25 + and CD3 + /CD8 + /CD25 + T cells, and CD14 + /CD16 + /HLA-DR + intermediate monocytes, and lower levels of CD14 + /CD16-/HLA-DR + classical monocytes, indicating greater amounts of inflammation and immune dysregulation. We also found a sex-dependent effect of exposure to social adversity (i.e., low social status). High-status males, relative to females, had higher CD20 + /CD3 + ratios and CD16 + /CD3 Natural Killer cell proportions, and lower proportions of CD8 + Cytotoxic T cells. Further, low-status females had higher proportions of cytotoxic T cells than high-status females, while the opposite was observed in males. High-status males had higher CD20 + /CD3 + ratios than low-status males. Together, our study identifies the strong age and sex-dependent effects of social adversity on immune cell proportions in a human-relevant primate model. Thus, these results provide novel insights into the combined effects of demography and social adversity on immunity and their potential contribution to age-related diseases in humans and other animals.


Asunto(s)
Antígenos HLA-DR , Alienación Social , Masculino , Femenino , Animales , Humanos , Macaca mulatta , Linfocitos T CD8-positivos , Inflamación
4.
Neurosci Biobehav Rev ; 154: 105424, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37827475

RESUMEN

Social adversity can increase the age-associated risk of disease and death, yet the biological mechanisms that link social adversities to aging remain poorly understood. Long-term naturalistic studies of nonhuman animals are crucial for integrating observations of social behavior throughout an individual's life with detailed anatomical, physiological, and molecular measurements. Here, we synthesize the body of research from one such naturalistic study system, Cayo Santiago, which is home to the world's longest continuously monitored free-ranging population of rhesus macaques (Macaca mulatta). We review recent studies of age-related variation in morphology, gene regulation, microbiome composition, and immune function. We also discuss ecological and social modifiers of age-markers in this population. In particular, we summarize how a major natural disaster, Hurricane Maria, affected rhesus macaque physiology and social structure and highlight the context-dependent and domain-specific nature of aging modifiers. Finally, we conclude by providing directions for future study, on Cayo Santiago and elsewhere, that will further our understanding of aging across different domains and how social adversity modifies aging processes.


Asunto(s)
Envejecimiento , Conducta Social , Animales , Macaca mulatta/fisiología , Biología
5.
bioRxiv ; 2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36747827

RESUMEN

Social adversity can increase the age-associated risk of disease and death, yet the biological mechanisms that link social adversities to aging remain poorly understood. Long-term naturalistic studies of nonhuman animals are crucial for integrating observations of social behavior throughout an individual's life with detailed anatomical, physiological, and molecular measurements. Here, we synthesize the body of research from one such naturalistic study system, Cayo Santiago Island, which is home to the world's longest continuously monitored free-ranging population of rhesus macaques. We review recent studies of age-related variation in morphology, gene regulation, microbiome composition, and immune function. We also discuss ecological and social modifiers of age-markers in this population. In particular, we summarize how a major natural disaster, Hurricane Maria, affected rhesus macaque physiology and social structure and highlight the context-dependent and domain-specific nature of aging modifiers. Finally, we conclude by providing directions for future study, on Cayo Santiago and elsewhere, that will further our understanding of aging across different domains and how social adversity modifies aging processes.

6.
Health Mark Q ; 40(4): 352-374, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36576207

RESUMEN

COVID-19 is a severe and ongoing threat globally, with the spread disrupting lives and society. Despite the developments of vaccines, the key measure to reduce the transmission of variants has stemmed from mass changes to personal behaviours. COVID-19 pandemic offers a unique context, where the protection behaviours enacted by an individual are necessary to keep the community safe. A social psychological perspective can be used to understand the reasons for adherence to policies and determine what other factors can shape preventive behaviours. To resolve this, in partnership with health consumers we use an online survey, with the findings substantiating preventive behaviours are positively related to COVID-19 information access and descriptive norms. Additionally, findings demonstrate the mediating role of injunctive norms on preventive behaviour suggesting that policy makers can influence decision-making by promoting health information that provides guidance on acceptable behaviours, but also demonstrates subsequent success. The integrity of the model is substantiated by partial least squares (PLS) testing.

7.
iScience ; 25(11): 105454, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36405777

RESUMEN

Sociality has been linked to a longer lifespan in many mammals, including humans. Yet, how sociality results in survival benefits remains unclear. Using 10 years of data and over 1,000 recorded injuries in rhesus macaques (Macaca mulatta), we tested two injury-related mechanisms by which social status and affiliative partners might influence survival. Injuries increased individual risk of death by 3-fold in this dataset. We found that sociality can affect individuals' survival by reducing their risk of injury but had no effect on the probability of injured individuals dying. Both males and females of high social status (measured as female matrilineal rank and male group tenure) and females with more affiliative partners (estimated using the number of female relatives) experienced fewer injuries and thus were less likely to die. Collectively, our results offer rare insights into one mechanism that can mediate the well-known benefits of sociality on an individual's fitness.

8.
Physiol Behav ; 241: 113560, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34454245

RESUMEN

Social integration and social status can substantially affect an individual's health and survival. One route through which this occurs is by altering immune function, which can be highly sensitive to changes in the social environment. However, we currently have limited understanding of how sociality influences markers of immunity in naturalistic populations where social dynamics can be fully realized. To address this gap, we asked if social integration and social status in free-ranging rhesus macaques (Macaca mulatta) predict anatomical and physiological markers of immunity. We used data on agonistic interactions to determine social status, and social network analysis of grooming interactions to generate measures of individual variation in social integration. As measures of immunity, we included the size of two of the major organs involved in the immune response, the spleen and liver, and counts of three types of blood cells (red blood cells, platelets, and white blood cells). Controlling for body mass and age, we found that neither social status nor social integration predicted the size of anatomical markers of immunity. However, individuals that were more socially connected, i.e., with more grooming partners, had lower numbers of white blood cells than their socially isolated counterparts, indicating lower levels of inflammation with increasing levels of integration. These results build upon and extend our knowledge of the relationship between sociality and the immune system in humans and captive animals to free-ranging primates, demonstrating generalizability of the beneficial role of social integration on health.


Asunto(s)
Conducta Social , Medio Social , Animales , Aseo Animal , Macaca mulatta
10.
BMJ Open ; 11(3): e045343, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727273

RESUMEN

OBJECTIVES: To determine the extent and nature of changes in utilisation of healthcare services during COVID-19 pandemic. DESIGN: Systematic review. ELIGIBILITY: Eligible studies compared utilisation of services during COVID-19 pandemic to at least one comparable period in prior years. Services included visits, admissions, diagnostics and therapeutics. Studies were excluded if from single centres or studied only patients with COVID-19. DATA SOURCES: PubMed, Embase, Cochrane COVID-19 Study Register and preprints were searched, without language restrictions, until 10 August, using detailed searches with key concepts including COVID-19, health services and impact. DATA ANALYSIS: Risk of bias was assessed by adapting the Risk of Bias in Non-randomised Studies of Interventions tool, and a Cochrane Effective Practice and Organization of Care tool. Results were analysed using descriptive statistics, graphical figures and narrative synthesis. OUTCOME MEASURES: Primary outcome was change in service utilisation between prepandemic and pandemic periods. Secondary outcome was the change in proportions of users of healthcare services with milder or more severe illness (eg, triage scores). RESULTS: 3097 unique references were identified, and 81 studies across 20 countries included, reporting on >11 million services prepandemic and 6.9 million during pandemic. For the primary outcome, there were 143 estimates of changes, with a median 37% reduction in services overall (IQR -51% to -20%), comprising median reductions for visits of 42% (-53% to -32%), admissions 28% (-40% to -17%), diagnostics 31% (-53% to -24%) and for therapeutics 30% (-57% to -19%). Among 35 studies reporting secondary outcomes, there were 60 estimates, with 27 (45%) reporting larger reductions in utilisation among people with a milder spectrum of illness, and 33 (55%) reporting no difference. CONCLUSIONS: Healthcare utilisation decreased by about a third during the pandemic, with considerable variation, and with greater reductions among people with less severe illness. While addressing unmet need remains a priority, studies of health impacts of reductions may help health systems reduce unnecessary care in the postpandemic recovery. PROSPERO REGISTRATION NUMBER: CRD42020203729.


Asunto(s)
COVID-19 , Servicios de Salud/estadística & datos numéricos , Pandemias , Aceptación de la Atención de Salud/estadística & datos numéricos , Atención a la Salud , Humanos
11.
PLoS One ; 15(9): e0238719, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32881958

RESUMEN

INTRODUCTION: Aboriginal and Torres Strait Islander Australians living in remote locations suffer disproportionately from chronic hepatitis B (CHB). Defining the temporospatial epidemiology of the disease-and assessing the ability of local clinicians to deliver optimal care-is crucial to improving patient outcomes in these settings. METHODS: The demographic, laboratory and radiology findings in all patients diagnosed with CHB after 1990, and presently residing in remote Far North Queensland (FNQ), tropical Australia, were correlated with their management and clinical course. RESULTS: Of the 602 patients, 514 (85%) identified as Aboriginal and Torres Strait Islander Australians, 417 (69%) of whom had Torres Strait Islander heritage. Among the 514 Aboriginal and Torres Strait Islander Australians, there were only 61 (12%) born after universal postnatal vaccination was introduced in 1985. Community CHB prevalence varied significantly across the region from 7/1707 (0.4%) in western Cape York to 55/806 (6.8%) in the Eastern Torres Strait Islands. Although 240/602 (40%) are engaged in care, with 65 (27%) meeting criteria for antiviral therapy, only 43 (66%) were receiving this treatment. Among 537 with complete data, 32 (6%) were cirrhotic, of whom 15 (47%) were engaged in care and 10 (33%) were receiving antiviral therapy. Only 64/251 (26%) in whom national guidelines would recommend hepatocellular carcinoma (HCC) surveillance are receiving screening, however, only 20 patients have been diagnosed with HCC since 1999. CONCLUSION: Vaccination has had a dramatic effect on CHB prevalence in FNQ in only a generation. However, although engagement in care is the highest in Australia, this is not translating into initiation of antiviral therapy in all those that should be receiving it, increasing their risk of developing cirrhosis and HCC. New strategies are necessary to improve the care of Indigenous Australians living with CHB to reduce the morbidity and mortality of this preventable disease.


Asunto(s)
Hepatitis B Crónica/epidemiología , Clima Tropical , Adulto , Anciano , Femenino , Geografía , Humanos , Masculino , Persona de Mediana Edad , Queensland/epidemiología
12.
Aust J Rural Health ; 25(5): 275-284, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28618108

RESUMEN

OBJECTIVE: To study the demographic, rates and types of chronic respiratory conditions in Indigenous and non-Indigenous patients in regional and remote communities of Northern Territory Top End, who were referred to the specialist respiratory outreach service. DESIGN: A retrospective, observational study over a 2 years period. SETTING: Remote community health clinics within the Northern Territory Top End visited by the specialist respiratory outreach team. PARTICIPANTS: Only patients referred to respiratory specialist outreach team were included. There were 444 participants, with 210 males and 234 females. In total, 79.3% were Indigenous. MAIN OUTCOME MEASURES: The rates of chronic respiratory disease diagnoses and smoking status within the different communities and health district regions. RESULTS: Chronic obstructive pulmonary disease (COPD) was the most common primary respiratory condition in our cohort of patients (50.5%) followed by sleep apnoea in (14.2%), bronchiectasis in (11.6%), asthma (11%), interstitial lung disease (2.5%), nodule/cancer (1.8%) sarcoidosis (0.2%) and others (9.2%). COPD, smoking status and bronchiectasis was more frequently noted among the Indigenous patients compared to non-Indigenous patients (56.3% versus 28.3%, P < 0.001), (52.6% versus 25.0%, P < 0.001), and (12.5% versus 3.3%, P = 0.01) respectively. Obstructive sleep apnoea was more commonly diagnosed in non-Indigenous patients. CONCLUSION: Indigenous patients of the remote and rural communities of the Top End have significantly higher rates of smoking and COPD compared to non-Indigenous patients. Bronchiectasis is also more common among Indigenous patients. Further efforts are warranted to develop strategies to address the disparity and optimise the respiratory outreach service to this population.


Asunto(s)
Enfermedad Crónica/epidemiología , Promoción de la Salud/métodos , Servicios de Salud del Indígena/estadística & datos numéricos , Nativos de Hawái y Otras Islas del Pacífico/estadística & datos numéricos , Enfermedades Respiratorias/epidemiología , Servicios de Salud Rural/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Northern Territory/epidemiología , Estudios Retrospectivos
13.
Sci Data ; 3: 160088, 2016 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-27727235

RESUMEN

Atmospheric CO2 concentrations have been steadily increasing since the Industrial Era and contribute to concurrent increases in global temperatures. Many observational studies suggest climate warming alone contributes to a longer growing season. To determine the relative effect of warming on plant phenology, we investigated the individual and joint effects of warming and CO2 enrichment on a mixed-grass prairie plant community by following the development of six common grassland species and recording four major life history events. Our data support that, in a semi-arid system, while warming advances leaf emergence and flower production, it also expedites seed maturation and senescence at the species level. However, the additive effect can be an overall lengthening of the growing and reproductive seasons since CO2 enrichment, particularly when combined with warming, contributed to a longer growing season by delaying plant maturation and senescence. Fostering synthesis across multiple phenology datasets and identifying key factors affecting plant phenology will be vital for understanding regional plant community responses to climate change.


Asunto(s)
Cambio Climático , Pradera , Dióxido de Carbono
14.
BMC Ecol ; 16: 1, 2016 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-26738753

RESUMEN

BACKGROUND: Currently, many species are facing serious conservation problems due to habitat loss. The impact of the potential loss of biodiversity associated with habitat loss is difficult to measure. This is particularly the case with inconspicuous species such as the threatened pudú (Pudu puda), an endemic Cervidae of temperate forests of Chile and Argentina. To evaluate the effectiveness of the Chilean protected-area system in protecting the habitat of the pudú, we measured the congruence between this specie's potential distribution and the geographical area occupied by the protected areas in central and southern Chile. The measurements of congruency were made using the Maxent modeling method. RESULTS: The potential habitat of the pudú was found to be poorly represented in the system (3-8%) and even the most suitable areas for the species are not currenly protected. According to these results, the protected area network cannot be considered as a key component of the conservation strategy for this species. CONCLUSIONS: The results presented here also serve as a guide for the reevaluation of current pudú conservation strategies, for the design of new field studies to detect the presence of this species in human-disturbed areas or remaining patches of native forest, and for the implementation of corridors to maximize the success of conservation efforts.


Asunto(s)
Conservación de los Recursos Naturales , Ciervos , Especies en Peligro de Extinción , Animales , Chile , Ecosistema
15.
Nature ; 510(7504): 259-62, 2014 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-24759322

RESUMEN

Observations of a longer growing season through earlier plant growth in temperate to polar regions have been thought to be a response to climate warming. However, data from experimental warming studies indicate that many species that initiate leaf growth and flowering earlier also reach seed maturation and senesce earlier, shortening their active and reproductive periods. A conceptual model to explain this apparent contradiction, and an analysis of the effect of elevated CO2--which can delay annual life cycle events--on changing season length, have not been tested. Here we show that experimental warming in a temperate grassland led to a longer growing season through earlier leaf emergence by the first species to leaf, often a grass, and constant or delayed senescence by other species that were the last to senesce, supporting the conceptual model. Elevated CO2 further extended growing, but not reproductive, season length in the warmed grassland by conserving water, which enabled most species to remain active longer. Our results suggest that a longer growing season, especially in years or biomes where water is a limiting factor, is not due to warming alone, but also to higher atmospheric CO2 concentrations that extend the active period of plant annual life cycles.


Asunto(s)
Dióxido de Carbono/metabolismo , Ecosistema , Calentamiento Global , Estaciones del Año , Dióxido de Carbono/farmacología , Clima , Poaceae/efectos de los fármacos , Reproducción , Suelo/química , Factores de Tiempo , Agua/análisis , Agua/metabolismo , Agua/farmacología , Wyoming
16.
Genes Cancer ; 4(1-2): 3-14, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23946867

RESUMEN

Adenosine monophosphate-activated protein kinase (AMPK) is a metabolic regulator that promotes energy conservation and restoration when cells are exposed to nutrient stress. Given the high metabolic requirement of cancer cells, AMPK activation has been suggested as a potential preventative and therapeutic target. However, previous findings have shown that AMPK activity is diminished in some cancers. Expression of the 2 catalytic isoforms, AMPKα1 and AMPKα2, was evaluated in primary breast cancer and matched nontumor-adjacent tissue samples using immunohistochemistry. AMPK-dependent growth signaling events were examined in primary human mammary epithelial cells (HMECs) using RNAi to understand the importance of AMPKα2 in normal growth regulation. To test whether AMPKα2 would reinstate growth control and apoptotic mechanisms in breast cancer cells, metabolic stress assays and tumor xenografts were performed in MCF-7 cells, expressing low levels of AMPKα2, with stable transfection of either green fluorescent protein (GFP) or AMPKα2 expression constructs. AMPKα2 was found to be significantly suppressed in breast cancer tissue samples, whereas AMPKα1 was not. In normal HMECs, low glucose stress resulted in AMPK-driven growth inhibition. Interestingly, this response was ablated when AMPKα2 was silenced. Metabolic stress assays in MCF-7 cells indicated that AMPKα2 expression reduced both mTOR signaling and cyclin D1 expression, contributing to G1-phase cell cycle arrest. Cells expressing AMPKα2 underwent apoptosis more readily than GFP control cells. Xenograft studies demonstrated that MCF-7 tumors expressing AMPKα2 display reduced proliferation and increased apoptotic events. Furthermore, AMPKα2 xenografts exhibited diminished cyclin D1 levels along with an increased amount of nuclear p53, thereby implicating the AMPKα2-p53 signaling axis as a mediator of cell apoptosis. Together, these results highlight the significance of reduced AMPK activity contributing to human carcinogenesis and, specifically, the role of AMPKα2 with respect to its control of normal mammary epithelial cell growth and its reduced expression in breast cancer.

17.
Genes Cancer ; 3(1): 51-62, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22893790

RESUMEN

AMP-activated kinase (AMPK) is a key metabolic sensor and stress signaling kinase. AMPK activity is known to suppress anabolic processes such as protein and lipid biosynthesis and promote energy-producing pathways including fatty acid oxidation, resulting in increased cellular energy. In addition, AMPK localizes to centrosomes during cell division, plays a role in cellular polarization, and directly targets p53, affecting apoptosis. Two distinct catalytic AMPKα isoforms exist: α1 and α2. Multiple reports indicate that both common and distinct functions exist for each of the 2 α isoforms. AMPK activation has been shown to repress tumor growth, and it has been suggested that AMPK may function as a metabolic tumor suppressor. To evaluate the potential role of each of the AMPKα isoforms in modulating cellular transformation, susceptibility to Ras-induced transformation was evaluated in normal murine embryonic fibroblasts (MEFs) obtained from genetically deleted AMPKα1- or AMPKα2-null mice. This study demonstrated that while AMPKα1 is the dominant AMPK isoform expressed in MEFs, only the AMPKα2-null MEFs displayed increased susceptibility to H-RasV12 transformation in vitro and tumorigenesis in vivo. Conversely, AMPKα1-null MEFs, which demonstrated compensation with increased expression of AMPKα2, displayed minimal transformation susceptibility, decreased cell survival, decreased cell proliferation, and increased apoptosis. Finally, this study demonstrates that AMPKα2 was selectively responsible for targeting p53, thus contributing to the suppression of transformation and tumorigenic mechanisms.

18.
Breast Cancer Res Treat ; 123(2): 333-44, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20204498

RESUMEN

Dietary energy restriction has been shown to repress both mammary tumorigenesis and aggressive mammary tumor growth in animal studies. Metformin, a caloric restriction mimetic, has a long history of safe use as an insulin sensitizer in diabetics and has been shown to reduce cancer incidence and cancer-related mortality in humans. To determine the potential impact of dietary energy availability and metformin therapy on aggressive breast tumor growth and metastasis, an orthotopic syngeneic model using triple negative 66cl4 tumor cells in Balb/c mice was employed. The effect of dietary restriction, a standard maintenance diet or a diet with high levels of free sugar, were tested for their effects on tumor growth and secondary metastases to the lung. Metformin therapy with the various diets indicated that metformin can be highly effective at suppressing systemic metabolic biomarkers such as IGF-1, insulin and glucose, especially in the high energy diet treated animals. Long-term metformin treatment demonstrated moderate yet significant effects on primary tumor growth, most significantly in conjunction with the high energy diet. When compared to the control diet, the high energy diet promoted tumor growth, expression of the inflammatory adipokines leptin and resistin, induced lung priming by bone marrow-derived myeloid cells and promoted metastatic potential. Metformin had no effect on adipokine expression or the development of lung metastases with the standard or the high energy diet. These data indicate that metformin may have tumor suppressing activity where a metabolic phenotype of high fuel intake, metabolic syndrome, and diabetes exist, but may have little or no effect on events controlling the metastatic niche driven by proinflammatory events.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/terapia , Restricción Calórica , Dieta/efectos adversos , Ingestión de Energía , Metabolismo Energético/efectos de los fármacos , Neoplasias Pulmonares/terapia , Metformina/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Adipoquinas/sangre , Animales , Autofagia/efectos de los fármacos , Biomarcadores/sangre , Glucemia/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Antígeno CD11b/metabolismo , Línea Celular Tumoral , Femenino , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Ratones , Ratones Endogámicos BALB C , Células Mieloides/efectos de los fármacos , Células Mieloides/inmunología , Factores de Tiempo , Carga Tumoral/efectos de los fármacos
19.
Fam Syst Health ; 27(4): 325-45, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20047356

RESUMEN

For women with an autoimmune illness, fatigue can be a debilitating symptom that impacts many aspects of their life. There is scant research on maternal fatigue and its impact on the caregiving environment for either well women or women with chronic illnesses. The objective of this study was to examine the role maternal fatigue played in the caregiving environment, specifically in the mother's experience of the daily hassles of parenting, the discipline style she employed, and how she monitored her child's whereabouts. Two-hundred sixty-two mothers participated in this study: 103 mothers with multiple sclerosis (MS), 68 mothers with rheumatoid arthritis (RA), and a comparison group of 91 well mothers. Mothers completed questionnaires assessing their self-reported levels of fatigue, depression, quality and quantity of sleep, parenting daily hassles, discipline styles, and monitoring. After sleep, depression, and number of children were controlled for, fatigue explained additional variance in predicting monitoring for all three groups of mothers. Fatigue was also a significant predictor of parenting daily hassles for both well mothers and mothers with RA, but not for mothers with MS. For mothers with MS, it was the covariates (i.e., the number of children in the family and sleep quality and quantity) that were predictive of parenting daily hassles. Several explanations for mothers with MS not being as influenced by fatigue are discussed.


Asunto(s)
Crianza del Niño , Fatiga/complicaciones , Conducta Materna , Responsabilidad Parental , Adulto , Artritis Reumatoide/complicaciones , Estudios de Casos y Controles , Preescolar , Recolección de Datos , Femenino , Humanos , Lactante , Relaciones Madre-Hijo , Esclerosis Múltiple/complicaciones
20.
Langmuir ; 24(17): 9727-38, 2008 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-18661961

RESUMEN

Laponite films provide versatile inorganic scaffolds with materials architectures that direct the self-assembly of CdSe quantum dots (QDs or EviTags) and catalytic surfaces that promote the in situ polymerization of polyaniline (PANI) to yield novel nanocomposites for light emitting diodes (LEDs) and solar cell applications. Water-soluble CdSe EviTags with varying, overlapping emission wavelengths in the visible spectrum were incorporated using soft chemistry routes within Na-Laponite host film platforms to achieve broadband emission in the visible spectrum. QD concentrations, composition and synthesis approach were varied to optimize photophysical properties of the films and to mediate self-assembly, optical cascading and energy transfer. In addition, aniline tetramers coupled to CdSe (QD-AT) surfaces using a dithioate linker were embedded within Cu-Laponite nanoscaffolds and electronically coupled to PANI via vapor phase exposure. Nanotethering and specific host-guest and guest-guest interactions that mediate nanocomposite photophysical behavior were probed using electronic absorption and fluorescence spectroscopies, optical microscopy, AFM, SEM, powder XRD, NMR and ATR-FTIR. Morphology studies indicated that Lap/QD-AT films synthesized using mixed solvent, layer by layer (LbL) methods exhibited anisotropic supramolecular structures with unique mesoscopic ordering that affords bifunctional networks to optimize charge transport.


Asunto(s)
Compuestos de Anilina/química , Compuestos de Cadmio/química , Nanocompuestos/química , Nanotecnología/métodos , Compuestos de Selenio/química , Silicatos/química , Luz , Espectroscopía de Resonancia Magnética , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Nanopartículas/química , Fotoquímica/métodos , Puntos Cuánticos , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Difracción de Rayos X
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