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1.
Development ; 151(6)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38493802

RESUMEN

Many genes that regulate development share a 180 bp DNA sequence, called the homeobox, encoding a 60 amino acid DNA-binding domain ( McGinnis et al., 1984c; Scott and Weiner, 1984). Because the homeobox is long enough to hybridize to related, but different, genes, it has been a powerful tool for discovering developmental regulators. This year is the 40th anniversary of the first homeobox report. Here, I describe work carried out at Indiana University that led to the discovery of the homeobox. The accompanying Perspective from McGinnis and Levine describes the independent discovery made at the Biozentrum in Basel ( McGinnis and Levine, 2024). At the time, the competition was lively but, as we all met each other - and realized that no one cares more about your work than competitors - we fortunately became friends and have enjoyed many years of following and respecting each other's work.


Asunto(s)
Proteínas de Unión al ADN , Genes Homeobox , Humanos , Secuencia de Aminoácidos , Proteínas de Unión al ADN/genética , Secuencia de Bases , Proteínas de Homeodominio/genética
2.
Intern Med J ; 54(6): 909-915, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38145421

RESUMEN

BACKGROUND: JAK2-mutated polycythaemia vera (PV) is associated with reduced survival because of thrombotic events and haematological disease transformation. Therapeutic venesection has traditionally been used to lower haematocrit, but the technique of erythrocytapheresis has emerged over the last decade. AIM: To compare erythrocytapheresis with venesection as treatment for PV by assessing medical efficacy and financial viability. METHODS: One hundred sixteen patients with PV who received red cell depletion therapy at Barwon Health between 2014 and 2021 were identified. The haematocrit drop after each session, interval between treatment times and number of sessions required to achieve a haematocrit <0.45 were compared with an independent t test. Thrombosis rates were compared with Pearson's chi-squared test. Cost-funding analysis was done by assessing the Weighted Inlier Equivalent Separation and National Weighted Activity Unit funding models. RESULTS: Patients treated with erythrocytapheresis achieved a greater haematocrit drop each treatment session (0.075 vs 0.03, P < 0.01), required fewer sessions to achieve a haematocrit <0.45 (1 vs 4, P < 0.01) and experienced fewer thrombotic complications (8.7% vs 32.1%, P = 0.02) than those treated with venesection. Cost-funding analysis demonstrated that erythrocytapheresis was more financially viable with a surplus of AU$297 per session compared to a deficit of AU$176 with venesection. Even if funding for venesection is increased, the cost of erythrocytapheresis may be mitigated by a lower number of procedures required per year (3.8 vs 5.3, P < 0.01). CONCLUSIONS: Erythrocytapheresis is more efficacious than venesection for the treatment of PV and is accompanied by rapid reductions in haematocrit and reduced thrombotic complications.


Asunto(s)
Janus Quinasa 2 , Policitemia Vera , Humanos , Masculino , Femenino , Persona de Mediana Edad , Policitemia Vera/terapia , Janus Quinasa 2/genética , Anciano , Hematócrito , Flebotomía/métodos , Adulto , Mutación , Estudios Retrospectivos , Citaféresis/métodos , Resultado del Tratamiento , Trombosis , Policitemia/terapia
3.
BMC Health Serv Res ; 24(1): 492, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643146

RESUMEN

BACKGROUND: Homelessness is associated with significant health disparities. Conventional health services often fail to address the unique needs and lived experience of homeless individuals and fail to include participatory design when planning health services. This scoping review aimed to examine areas of patient experience that are most frequently reported by people experiencing homelessness when seeking and receiving healthcare, and to identify existing surveys used to measure patient experience for this cohort. METHODS: A scoping review was undertaken reported according to the PRISMA-ScR 2020 Statement. Databases were searched on 1 December 2022: MEDLINE, EMBASE, APA PsychINFO and CINAHL. Included studies focused on people experiencing homelessness, healthcare services and patient experience, primary research, published in English from 2010. Qualitative papers and findings were extracted and synthesized against a modified framework based on the National Institute for Health and Care Excellence guidelines for care for people experiencing homelessness, the Institute of Medicine Framework and Lachman's multidimensional quality model. People with lived experience of homelessness were employed as part of the research team. RESULTS: Thirty-two studies were included. Of these, 22 were qualitative, seven quantitative and three mixed methods, from the United States of America (n = 17), United Kingdom (n = 5), Australia (n = 5) and Canada (n = 4). Health services ranged from primary healthcare to outpatient management, acute care, emergency care and hospital based healthcare. In qualitative papers, the domains of 'accessible and timely', 'person-centred', and values of 'dignity and respect' and 'kindness with compassion' were most prevalent. Among the three patient experience surveys identified, 'accessible and timely' and 'person-centred' were the most frequent domains. The least frequently highlighted domains and values were 'equitable' and 'holistic'. No questions addressed the 'safety' domain. CONCLUSIONS: The Primary Care Quality-Homeless questionnaire best reflected the priorities for healthcare provision that were highlighted in the qualitative studies of people experiencing homelessness. The most frequently cited domains and values that people experiencing homelessness expressed as important when seeking healthcare were reflected in each of the three survey tools to varying degrees. Findings suggest that the principles of 'Kindness and compassion' require further emphasis when seeking feedback on healthcare experiences and the domains of 'safety', 'equitable', and 'efficiency' are not adequately represented in existing patient experience surveys.


Asunto(s)
Personas con Mala Vivienda , Personas con Mala Vivienda/psicología , Humanos , Satisfacción del Paciente , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Accesibilidad a los Servicios de Salud
4.
J Sport Exerc Psychol ; 46(4): 191-204, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38714304

RESUMEN

Combined use of action observation and motor imagery (AOMI) is an increasingly popular motor-simulation intervention, which involves observing movements on video while simultaneously imagining the feeling of movement execution. Measuring and reporting participant imagery-ability characteristics are essential in motor-simulation research, but no measure of AOMI ability currently exists. Accordingly, the AOMI Ability Questionnaire (AOMI-AQ) was developed to address this gap in the literature. In Study 1, two hundred eleven participants completed the AOMI-AQ and the kinesthetic imagery subscales of the Movement Imagery Questionnaire-3 and Vividness of Motor Imagery Questionnaire-2. Following exploratory factor analysis, an 8-item AOMI-AQ was found to correlate positively with existing motor-imagery measures. In Study 2, one hundred seventy-four participants completed the AOMI-AQ for a second time after a period of 7-10 days. Results indicate a good test-retest reliability for the AOMI-AQ. The new AOMI-AQ measure provides a valid and reliable tool for researchers and practitioners wishing to assess AOMI ability.


Asunto(s)
Imaginación , Movimiento , Humanos , Masculino , Femenino , Encuestas y Cuestionarios , Adulto , Reproducibilidad de los Resultados , Adulto Joven , Adolescente , Cinestesia , Psicometría , Persona de Mediana Edad
5.
Mol Syst Biol ; 18(5): e10441, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35620827

RESUMEN

In natural environments, bacteria are frequently exposed to sub-lethal levels of DNA damage, which leads to the induction of a stress response (the SOS response in Escherichia coli). Natural environments also vary in nutrient availability, resulting in distinct physiological changes in bacteria, which may have direct implications on their capacity to repair their chromosomes. Here, we evaluated the impact of varying the nutrient availability on the expression of the SOS response induced by chronic sub-lethal DNA damage in E. coli. We found heterogeneous expression of the SOS regulon at the single-cell level in all growth conditions. Surprisingly, we observed a larger fraction of high SOS-induced cells in slow growth as compared with fast growth, despite a higher rate of SOS induction in fast growth. The result can be explained by the dynamic balance between the rate of SOS induction and the division rates of cells exposed to DNA damage. Taken together, our data illustrate how cell division and physiology come together to produce growth-dependent heterogeneity in the DNA damage response.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Proteínas Bacterianas/metabolismo , Daño del ADN , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Respuesta SOS en Genética
6.
Ann Neurol ; 92(3): 358-363, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35670654

RESUMEN

Autosomal-dominant, Dutch-type cerebral amyloid angiopathy (D-CAA) offers a unique opportunity to develop biomarkers for pre-symptomatic cerebral amyloid angiopathy (CAA). We hypothesized that neuroimaging measures of white matter injury would be present and progressive in D-CAA prior to hemorrhagic lesions or symptomatic hemorrhage. In a longitudinal cohort of D-CAA carriers and non-carriers, we observed divergence of white matter injury measures between D-CAA carriers and non-carriers prior to the appearance of cerebral microbleeds and >14 years before the average age of first symptomatic hemorrhage. These results indicate that white matter disruption measures may be valuable cross-sectional and longitudinal biomarkers of D-CAA progression. ANN NEUROL 2022;92:358-363.


Asunto(s)
Angiopatía Amiloide Cerebral , Sustancia Blanca , Angiopatía Amiloide Cerebral/diagnóstico por imagen , Angiopatía Amiloide Cerebral/patología , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/patología , Estudios Transversales , Hemorragia/patología , Humanos , Imagen por Resonancia Magnética , Neuroimagen , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología
7.
Artif Life ; 29(2): 198-234, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36995236

RESUMEN

Cooperative survival "games" are situations in which, during a sequence of catastrophic events, no one survives unless everyone survives. Such situations can be further exacerbated by uncertainty over the timing and scale of the recurring catastrophes, while the resource management required for survival may depend on several interdependent subgames of resource extraction, distribution, and investment with conflicting priorities and preferences between survivors. In social systems, self-organization has been a critical feature of sustainability and survival; therefore, in this article we use the lens of artificial societies to investigate the effectiveness of socially constructed self-organization for cooperative survival games. We imagine a cooperative survival scenario with four parameters: scale, that is, n in an n-player game; uncertainty, with regard to the occurrence and magnitude of each catastrophe; complexity, concerning the number of subgames to be simultaneously "solved"; and opportunity, with respect to the number of self-organizing mechanisms available to the players. We design and implement a multiagent system for a situation composed of three entangled subgames-a stag hunt game, a common-pool resource management problem, and a collective risk dilemma-and specify algorithms for three self-organizing mechanisms for governance, trading, and forecasting. A series of experiments shows, as perhaps expected, a threshold for a critical mass of survivors and also that increasing dimensions of uncertainty and complexity require increasing opportunity for self-organization. Perhaps less expected are the ways in which self-organizing mechanisms may interact in pernicious but also self-reinforcing ways, highlighting the need for some reflection as a process in collective self-governance for cooperative survival.


Asunto(s)
Algoritmos , Conducta Cooperativa , Teoría del Juego
8.
Int J Mol Sci ; 25(1)2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38203217

RESUMEN

Intermittent cold exposure (ICE) has garnered increased attention in popular culture, largely for its proposed effects on mood and immune function, but there are also suggestions that the energy-wasting mechanisms associated with thermogenesis may decrease body weight and fat mass. Considering the continued and worsening prevalence of obesity and type II diabetes, any protocol that can reduce body weight and/or improve metabolic health would be a substantial boon. Here, we present a narrative review exploring the research related to ICE and adipose tissue. Any publicly available original research examining the effects of repeated bouts of ICE on adipose-related outcomes was included. While ICE does not consistently lower body weight or fat mass, there does seem to be evidence for ICE as a positive modulator of the metabolic consequences of obesity, such as glucose tolerance and insulin signaling. Further, ICE consistently increases the activity of brown adipose tissue (BAT) and transitions white adipose tissue to a phenotype more in line with BAT. Lastly, the combined effects of ICE and exercise do not seem to provide any additional benefit, at least when exercising during ICE bouts. The majority of the current literature on ICE is based on rodent models where animals are housed in cold rooms, which does not reflect protocols likely to be implemented in humans such as cold water immersion. Future research could specifically characterize ICE via cold water immersion in combination with controlled calorie intake to clearly determine the effects of ICE as it would be implemented in humans looking to lower their body weight via reductions in fat mass.


Asunto(s)
Diabetes Mellitus Tipo 2 , Animales , Humanos , Tejido Adiposo Pardo , Peso Corporal , Obesidad , Agua
9.
Int J Mol Sci ; 24(17)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37686232

RESUMEN

Thiazolidinediones (TZD) significantly improve insulin sensitivity via action on adipocytes. Unfortunately, TZDs also degrade bone by inhibiting osteoblasts. An extract of Artemisia dracunculus L., termed PMI5011, improves blood glucose and insulin sensitivity via skeletal muscle, rather than fat, and may therefore spare bone. Here, we examine the effects of PMI5011 and an identified active compound within PMI5011 (2',4'-dihydroxy-4-methoxydihydrochalcone, DMC-2) on pre-osteoblasts. We hypothesized that PMI5011 and DMC-2 will not inhibit osteogenesis. To test our hypothesis, MC3T3-E1 cells were induced in osteogenic media with and without PMI5011 or DMC-2. Cell lysates were probed for osteogenic gene expression and protein content and were stained for osteogenic endpoints. Neither compound had an effect on early stain outcomes for alkaline phosphatase or collagen. Contrary to our hypothesis, PMI5011 at 30 µg/mL significantly increases osteogenic gene expression as early as day 1. Further, osteogenic proteins and cell culture mineralization trend higher for PMI5011-treated wells. Treatment with DMC-2 at 1 µg/mL similarly increased osteogenic gene expression and significantly increased mineralization, although protein content did not trend higher. Our data suggest that PMI5011 and DMC-2 have the potential to promote bone health via improved osteoblast maturation and activity.


Asunto(s)
Artemisia , Calcinosis , Resistencia a la Insulina , Colorantes , Osteoblastos , Proliferación Celular , Extractos Vegetales/farmacología
10.
Mol Psychiatry ; 26(12): 7813-7822, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34588623

RESUMEN

Noninvasive biomarkers of early neuronal injury may help identify cognitively normal individuals at risk of developing Alzheimer's disease (AD). A recent diffusion-weighted imaging (DWI) method allows assessing cortical microstructure via cortical mean diffusivity (cMD), suggested to be more sensitive than macrostructural neurodegeneration. Here, we aimed to investigate the association of cMD with amyloid-ß and tau pathology in older adults, and whether cMD predicts longitudinal cognitive decline, neurodegeneration and clinical progression. The study sample comprised n = 196 cognitively normal older adults (mean[SD] 72.5 [9.4] years; 114 women [58.2%]) from the Harvard Aging Brain Study. At baseline, all participants underwent structural MRI, DWI, 11C-Pittsburgh compound-B-PET, 18F-flortaucipir-PET imaging, and cognitive assessments. Longitudinal measures of Preclinical Alzheimer Cognitive Composite-5 were available for n = 186 individuals over 3.72 (1.96)-year follow-up. Prospective clinical follow-up was available for n = 163 individuals over 3.2 (1.7) years. Surface-based image analysis assessed vertex-wise relationships between cMD, global amyloid-ß, and entorhinal and inferior-temporal tau. Multivariable regression, mixed effects models and Cox proportional hazards regression assessed longitudinal cognition, brain structural changes and clinical progression. Tau, but not amyloid-ß, was positively associated with cMD in AD-vulnerable regions. Correcting for baseline demographics and cognition, increased cMD predicted steeper cognitive decline, which remained significant after correcting for amyloid-ß, thickness, and entorhinal tau; there was a synergistic interaction between cMD and both amyloid-ß and tau on cognitive slope. Regional cMD predicted hippocampal atrophy rate, independently from amyloid-ß, tau, and thickness. Elevated cMD predicted progression to mild cognitive impairment. Cortical microstructure is a noninvasive biomarker that independently predicts subsequent cognitive decline, neurodegeneration and clinical progression, suggesting utility in clinical trials.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Disfunción Cognitiva/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Estudios Prospectivos , Proteínas tau
11.
BMC Vet Res ; 18(1): 77, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35197051

RESUMEN

BACKGROUND: Transcriptomics has identified at-arrival differentially expressed genes associated with bovine respiratory disease (BRD) development; however, their use as prediction molecules necessitates further evaluation. Therefore, we aimed to selectively analyze and corroborate at-arrival mRNA expression from multiple independent populations of beef cattle. In a nested case-control study, we evaluated the expression of 56 mRNA molecules from at-arrival blood samples of 234 cattle across seven populations via NanoString nCounter gene expression profiling. Analysis of mRNA was performed with nSolver Advanced Analysis software (p < 0.05), comparing cattle groups based on the diagnosis of clinical BRD within 28 days of facility arrival (n = 115 Healthy; n = 119 BRD); BRD was further stratified for severity based on frequency of treatment and/or mortality (Treated_1, n = 89; Treated_2+, n = 30). Gene expression homogeneity of variance, receiver operator characteristic (ROC) curve, and decision tree analyses were performed between severity cohorts. RESULTS: Increased expression of mRNAs involved in specialized pro-resolving mediator synthesis (ALOX15, HPGD), leukocyte differentiation (LOC100297044, GCSAML, KLF17), and antimicrobial peptide production (CATHL3, GZMB, LTF) were identified in Healthy cattle. BRD cattle possessed increased expression of CFB, and mRNA related to granulocytic processes (DSG1, LRG1, MCF2L) and type-I interferon activity (HERC6, IFI6, ISG15, MX1). Healthy and Treated_1 cattle were similar in terms of gene expression, while Treated_2+ cattle were the most distinct. ROC cutoffs were used to generate an at-arrival treatment decision tree, which classified 90% of Treated_2+ individuals. CONCLUSIONS: Increased expression of complement factor B, pro-inflammatory, and type I interferon-associated mRNA hallmark the at-arrival expression patterns of cattle that develop severe clinical BRD. Here, we corroborate at-arrival mRNA markers identified in previous transcriptome studies and generate a prediction model to be evaluated in future studies. Further research is necessary to evaluate these expression patterns in a prospective manner.


Asunto(s)
Complejo Respiratorio Bovino , Enfermedades de los Bovinos , Animales , Complejo Respiratorio Bovino/diagnóstico , Complejo Respiratorio Bovino/genética , Estudios de Casos y Controles , Bovinos , Enfermedades de los Bovinos/diagnóstico , Estudios Prospectivos , ARN Mensajero/genética , Transcriptoma
12.
Am J Physiol Endocrinol Metab ; 320(6): E1053-E1067, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33843280

RESUMEN

Ketogenic diets (KDs) are reported to improve body weight, fat mass, and exercise performance in humans. Unfortunately, most rodent studies have used a low-protein KD, which does not recapitulate diets used by humans. Since skeletal muscle plays a critical role in responding to macronutrient perturbations induced by diet and exercise, the purpose of this study was to test if a normal-protein KD (NPKD) impacts shifts in skeletal muscle substrate oxidative capacity in response to exercise training (ExTr). A high fat, carbohydrate-deficient NPKD (16.1% protein, 83.9% fat, 0% carbohydrate) was given to C57BL/6J male mice for 6 wk, whereas controls (Con) received a low-fat diet with similar protein (15.9% protein, 11.9% fat, 72.2% carbohydrate). After 3 wk on the diet, mice began treadmill training 5 days/wk, 60 min/day for 3 wks. The NPKD increased body weight and fat mass, whereas ExTr negated a continued rise in adiposity. ExTr increased intramuscular glycogen, whereas the NPKD increased intramuscular triglycerides. Neither the NPKD nor ExTr alone altered mitochondrial content; however, in combination, the NPKD-ExTr group showed increases in PGC-1α and markers of mitochondrial fission/fusion. Pyruvate oxidative capacity was unchanged by either intervention, whereas ExTr increased leucine oxidation in NPKD-fed mice. Lipid metabolism pathways had the most notable changes as the NPKD and ExTr interventions both enhanced mitochondrial and peroxisomal lipid oxidation and many adaptations were additive or synergistic. Overall, these results suggest that a combination of a NPKD and ExTr induces additive and/or synergistic adaptations in skeletal muscle oxidative capacity.NEW & NOTEWORTHY A ketogenic diet with normal protein content (NPKD) increases body weight and fat mass, increases intramuscular triglyceride storage, and upregulates pathways related to protein metabolism. In combination with exercise training, a NPKD induces additive and/or synergistic activation of AMPK, PGC-1α, mitochondrial fission/fusion genes, mitochondrial fatty acid oxidation, and peroxisomal adaptations in skeletal muscle. Collectively, results from this study provide mechanistic insight into adaptations in skeletal muscle relevant to keto-adaptation.


Asunto(s)
Dieta Cetogénica , Mitocondrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Peroxisomas/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Metabolismo de los Lípidos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Dinámicas Mitocondriales/fisiología , Oxidación-Reducción , Estrés Oxidativo/fisiología
13.
J Virol ; 94(2)2020 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-31666385

RESUMEN

Human papillomaviruses (HPVs) infect keratinocytes of stratified epithelia. Long-term persistence of infection is a critical risk factor for the development of HPV-induced malignancies. Through the actions of its oncogenes, HPV evades host immune responses to facilitate its productive life cycle. In this work, we discovered a previously unknown function of the HPV16 E5 oncoprotein in the suppression of interferon (IFN) responses. This suppression is focused on keratinocyte-specific IFN-κ and is mediated through E5-induced changes in growth factor signaling pathways, as identified through phosphoproteomics analysis. The loss of E5 in keratinocytes maintaining the complete HPV16 genome results in the derepression of IFNK transcription and subsequent JAK/STAT-dependent upregulation of several IFN-stimulated genes (ISGs) at both the mRNA and protein levels. We also established a link between the loss of E5 and the subsequent loss of genome maintenance and stability, resulting in increased genome integration.IMPORTANCE Persistent human papillomavirus infections can cause a variety of significant cancers. The ability of HPV to persist depends on evasion of the host immune system. In this study, we show that the HPV16 E5 protein can suppress an important aspect of the host immune response. In addition, we find that the E5 protein is important for helping the virus avoid integration into the host genome, which is a frequent step along the pathway to cancer development.


Asunto(s)
Genoma Viral , Papillomavirus Humano 16/metabolismo , Interferón Tipo I/metabolismo , Queratinocitos , Proteínas Oncogénicas Virales/metabolismo , Infecciones por Papillomavirus , Plásmidos/metabolismo , Transducción de Señal , Línea Celular , Inestabilidad Genómica , Papillomavirus Humano 16/genética , Humanos , Interferón Tipo I/genética , Queratinocitos/metabolismo , Queratinocitos/patología , Queratinocitos/virología , Proteínas Oncogénicas Virales/genética , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/metabolismo , Infecciones por Papillomavirus/patología , Plásmidos/genética
14.
Ann Neurol ; 87(2): 267-280, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31750553

RESUMEN

OBJECTIVE: Unawareness, or anosognosia, of memory deficits is a challenging manifestation of Alzheimer's disease (AD) that adversely affects a patient's safety and decision-making. However, there is a lack of consensus regarding the presence, as well as the evolution, of altered awareness of memory function across the preclinical and prodromal stages of AD. Here, we aimed to characterize change in awareness of memory abilities and its relationship to beta-amyloid (Aß) burden in a large cohort (N = 1,070) of individuals across the disease spectrum. METHODS: Memory awareness was longitudinally assessed (average number of visits = 4.3) and operationalized using the discrepancy between mean participant and partner report on the Everyday Cognition scale (memory domain). Aß deposition was measured at baseline using [18F]florbetapir positron emission tomographic imaging. RESULTS: Aß predicted longitudinal changes in memory awareness, such that awareness decreased faster in participants with increased Aß burden. Aß and clinical group interacted to predict change in memory awareness, demonstrating the strongest effect in dementia participants, but could also be found in the cognitively normal (CN) participants. In a subset of CN participants who progressed to mild cognitive impairment (MCI), heightened memory awareness was observed up to 1.6 years before MCI diagnosis, with memory awareness declining until the time of progression to MCI (-0.08 discrepant-points/yr). In a subset of MCI participants who progressed to dementia, awareness was low initially and continued to decline (-0.23 discrepant-points/yr), reaching anosognosia 3.2 years before dementia onset. INTERPRETATION: Aß burden is associated with a progressive decrease in self-awareness of memory deficits, reaching anosognosia approximately 3 years before dementia diagnosis. ANN NEUROL 2020;87:267-280.


Asunto(s)
Agnosia/metabolismo , Agnosia/psicología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Trastornos de la Memoria/complicaciones , Anciano , Agnosia/complicaciones , Enfermedad de Alzheimer/complicaciones , Progresión de la Enfermedad , Femenino , Neuroimagen Funcional , Humanos , Masculino , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Síntomas Prodrómicos , Estudios Prospectivos
15.
Ann Neurol ; 88(5): 921-932, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32799367

RESUMEN

OBJECTIVE: The goal of this study was to examine sex differences in tau distribution across the brain of older adults, using positron emission tomography (PET), and investigate how these differences might associate with cognitive trajectories. METHODS: Participants were 343 clinically normal individuals (women, 58%; 73.8 [8.5] years) and 55 individuals with mild cognitive impairment (MCI; women, 38%; 76.9 [7.3] years) from the Harvard Aging Brain Study and the Alzheimer's Disease Neuroimaging Initiative. We examined 18 F-Flortaucipir (FTP)-positron emission tomography (PET) signal across 41 cortical and subcortical regions of interest (ROIs). Linear regression models estimated the effect of sex on FTP-signal for each ROI after adjusting for age and cohort. We also examined interactions between sex*Aß-PET positive / negative (+ / -) and sex*apolipoprotein ε4 (APOEε4) status. Linear mixed models estimated the moderating effect of sex on the relationship between a composite of sex-differentiated tau ROIs and cognitive decline. RESULTS: Women showed significantly higher FTP-signals than men across multiple regions of the cortical mantle (p < 0.007). ß-amyloid (Aß)-moderated sex differences in tau signal were localized to medial and inferio-lateral temporal regions (p < 0.007); Aß + women exhibited greater FTP-signal than other groups. APOEε4-moderated sex differences in FTP-signal were only found in the lateral occipital lobe. Women with higher FTP-signals in composite ROI exhibited faster cognitive decline than men (p = 0.04). INTERPRETATION: Tau vulnerability in women is not just limited to the medial temporal lobe and significantly contributed to greater risk of faster cognitive decline. Interactive effects of sex and Aß were predominantly localized in the temporal lobe, however, sex differences in extra-temporal tau highlights the possibility of accelerated tau proliferation in women with the onset of clinical symptomatology. ANN NEUROL 2020;88:921-932.


Asunto(s)
Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/psicología , Tauopatías/diagnóstico por imagen , Tauopatías/psicología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/genética , Apolipoproteína E4/genética , Carbolinas , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Lóbulo Occipital/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos , Caracteres Sexuales , Lóbulo Temporal/diagnóstico por imagen
16.
Sleep Breath ; 25(1): 537-544, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32948936

RESUMEN

PURPOSE: Sleep is essential for overall health and can impact academic performance. Prior research reports reduced sleep time in college students. Poor sleep may impact physical activity (PA) and sedentary behavior, or vice versa, but has not been examined extensively in this population. Therefore, the purpose of this study was to examine markers of sleep quality, PA, and sedentary behavior in college students using objective means. METHODS: A convenience sample of college students underwent body composition analysis and 7-day objective PA and sleep assessment via accelerometry. RESULTS: Among 81 college students (53 women), there was no association between total sleep time (TST) and weekly average PA. TST was negatively associated with sedentary minutes per day, sedentary bouts per day, and total time in sedentary bouts per day. Greater sedentary bouts per day and average sedentary minutes per day were seen in those with a TST < 6 h, with no difference in body composition. Further, TST was negatively associated with sedentary minutes accumulated on the subsequent day, for all 7 days. CONCLUSION: In a primarily residential college student cohort, poor sleep is associated with sedentary behavior more than PA. These students, who require a high amount of transport PA to and from campus during the week, are compensating by sleeping more and moving less on the weekend.


Asunto(s)
Acelerometría , Conducta Sedentaria , Privación de Sueño/psicología , Ejercicio Físico , Femenino , Humanos , Masculino , Sueño , Privación de Sueño/complicaciones , Estudiantes/estadística & datos numéricos , Adulto Joven
17.
Neuroimage ; 220: 116991, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32512123

RESUMEN

Neurofibrillary tau tangles are a hallmark pathology of Alzheimer's disease (AD) and are more closely associated with AD-related cortical atrophy and symptom severity than amyloid-beta (Aß). However, studies regarding the effect of tau on longitudinal cortical thinning, particularly in healthy aging and preclinical AD, have been limited in number due to the relatively recent introduction of in vivo PET tracers for imaging tau pathology. Here, we investigate [18F]-flortaucipir (FTP, a marker of paired helical filament tau) PET as a predictor of atrophy in healthy aging and preclinical AD. We examine longitudinal structural MRI brain imaging data, retrospectively and prospectively relative to FTP imaging, using piecewise linear mixed-effect models with time centered at each participant's FTP-PET session. Participants include 111 individuals from the Harvard Aging Brain Study who underwent at least three MRI sessions over an average of 4.46 years and one FTP-PET at the approximate midpoint of the observation period. Our primary analyses focus on inferior temporal (IT) FTP standardized uptake value ratios and longitudinal FreeSurfer defined cortical regions of interest. Relationships were also explored using other regional FTP measures (entorhinal, composite, and local), within high and low Pittsburgh compound-B (PiB) PET groups, and with longitudinal subcortical volume. Strong associations between IT FTP and cortical thinning were found, most notably in temporal, midline, and prefrontal regions, with stronger effects generally observed in the prospective as compared to retrospective time frame. Significant differences between prospective and retrospective rates of thinning were found in the inferior and middle temporal gyri, cingulate areas, as well as pars orbitalis such that higher IT FTP was associated with greater prospective rates of thinning. Within the high PiB group, significant differences between prospective and retrospective rates of thinning were similarly observed. However, no consistent pattern of tau-related change in cortical thickness within the low PiB group was discerned. These results provide support for the hypothesis that tau pathology is a driver of future atrophy as well as provide additional evidence for tau-PET as an effective AD biomarker for interventional clinical trials.


Asunto(s)
Envejecimiento/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Adelgazamiento de la Corteza Cerebral/diagnóstico por imagen , Proteínas tau/metabolismo , Anciano , Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Adelgazamiento de la Corteza Cerebral/metabolismo , Adelgazamiento de la Corteza Cerebral/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Neurológicos , Ovillos Neurofibrilares/metabolismo , Ovillos Neurofibrilares/patología , Tomografía de Emisión de Positrones , Estudios Retrospectivos
18.
J Virol ; 93(19)2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31292244

RESUMEN

Human papillomaviruses (HPVs) infect squamous epithelia and cause several important cancers. Immune evasion is critical for viral persistence. Fibroblasts in the stromal microenvironment provide growth signals and cytokines that are required for proper epithelial differentiation, maintenance, and immune responses and are critical in the development of many cancers. In this study, we examined the role of epithelial-stromal interactions in the HPV16 life cycle using organotypic (raft) cultures as a model. Rafts were created using uninfected human foreskin keratinocytes (HFKs) and HFKs containing either wild-type HPV16 or HPV16 with a stop mutation to prevent the expression of the viral oncogene E5. Microarray analysis revealed significant changes in gene expression patterns in the stroma in response to HPV16, some of which were E5 dependent. Interferon (IFN)-stimulated genes (ISGs) and extracellular matrix remodeling genes were suppressed, the most prominent pathways affected. STAT1, IFNAR1, IRF3, and IRF7 were knocked down in stromal fibroblasts using lentiviral short hairpin RNA (shRNA) transduction. HPV late gene expression and viral copy number in the epithelium were increased when the stromal IFN pathway was disrupted, indicating that the stroma helps control the late phase of the HPV life cycle in the epithelium. Increased late gene expression correlated with increased late keratinocyte differentiation but not decreased IFN signaling in the epithelium. These studies show HPV16 has a paracrine effect on stromal innate immunity, reveal a new role for E5 as a stromal innate immune suppressor, and suggest that stromal IFN signaling may influence keratinocyte differentiation.IMPORTANCE The persistence of high-risk human papillomavirus (HPV) infections is the key risk factor for developing HPV-associated cancers. The ability of HPV to evade host immunity is a critical component of its ability to persist. The environment surrounding a tumor is increasingly understood to be critical in cancer development, including immune evasion. Our studies show that HPV can suppress the expression of immune-related genes in neighboring fibroblasts in a three-dimensional (3D) model of human epithelium. This finding is significant, because it indicates that HPV can control innate immunity not only in the infected cell but also in the microenvironment. In addition, the ability of HPV to regulate stromal gene expression depends in part on the viral oncogene E5, revealing a new function for this protein as an immune evasion factor.


Asunto(s)
Interacciones Huésped-Patógeno , Papillomavirus Humano 16/crecimiento & desarrollo , Papillomavirus Humano 16/inmunología , Evasión Inmune , Inmunidad Innata , Factores Inmunológicos/antagonistas & inhibidores , Interferones/antagonistas & inhibidores , Células Cultivadas , Fibroblastos/inmunología , Fibroblastos/virología , Perfilación de la Expresión Génica , Humanos , Queratinocitos/inmunología , Queratinocitos/virología , Modelos Biológicos , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Transducción de Señal
20.
BMC Microbiol ; 20(1): 15, 2020 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-31948391

RESUMEN

BACKGROUND: Understanding the patterns of species richness across elevational gradients is a key concept for contemporary research in ecology and evolution, and critical to understanding large-scale trends in biodiversity, global change and conservation. However, patterns of elevational species richness between taxonomic groups, regions and latitudes are inconsistent, so that various, sometimes conflicting hypotheses exist. Several scholars have pointed out that research on elevational distribution patterns is often biased by the sampling design employed. To test this hypothesis, we analyzed species richness of Nematode-Trapping Fungi (NTF) across an elevation gradient at two mountainous sites in western Yunnan Province, P.R. China. We tested for potential differences in the results when using different sampling designs. RESULTS: A total of 3 genera, 17 species, 222 strains of NTF were isolated and identified from Gaoligongshan and Cangshan. Species accumulation curves for both sites and sampling modes had acceptable leveling, demonstrating sufficient sampling effort. At Gaoligongshan, the elevation distribution patterns of NTF were different under two sampling patterns. When reducing the analyzed altitude range in Gaoligongshan, the elevation distribution pattern of the NTF changed. A similar elevation distribution pattern was observed in Cangshan when testing the same altitude range. In general, when treating the same dataset using different sampling designs, the resulting distribution patterns of species richness and occurrence frequencies were clearly different. Moreover, after removal of the samples located within lower-altitude zones affected by anthropogenic interferences, the distribution pattern of NTF in the two sites tended to become uniform. CONCLUSION: The sampling design, and in particular the elevation interval between plots, has a significant effect on the assessment of species distribution in mountainous regions. Other factors such as human activities and the multi-dimensionality of biodiversity also contribute to result biases. It is recommended that sampling design is given careful consideration in future studies on the elevational gradients of species richness, using stratified approaches according to the most relevant factors.


Asunto(s)
Hongos/clasificación , Nematodos/microbiología , Altitud , Animales , Biodiversidad , China , Demografía , Hongos/aislamiento & purificación , Actividades Humanas , Humanos , Especificidad de la Especie
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