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1.
R Soc Open Sci ; 11(3): 231470, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38511083

RESUMEN

Human activities can induce significant behavioural changes in wildlife. Often explored through extractive interactions (e.g. hunting) that can favour certain behavioural traits, the implications of non-extractive ones, such as wildlife feeding, remain understudied. Research shows that people tend to favour bolder individuals within populations despite their dynamics and consequences being unclear. Using fallow deer in a peri-urban environment, we studied whether mothers that show reduced fear of humans and consistently approach them for food adopt weaker anti-predator strategies by selecting less concealed fawning bedsites closer to human hotspots. This would provide the advantage of additional feeding opportunities in comparison with shyer mothers while keeping their fawns close. Our dataset encompassed 281 capture events of 172 fawns from 110 mothers across 4 years. Surprisingly, mothers that regularly accepted food from humans selected more concealed bedsites farther from human hotspots, giving their offspring better protection while also benefitting from additional food during lactation. Our results show behavioural adaptations by a subset of females and, for the first time, link the tendency to approach humans and strategies to protect offspring. Given previous findings that these begging females also deliver heavier fawns at birth, our research further investigates human-wildlife feeding interactions and their behavioural implications.

2.
BMC Med Educ ; 24(1): 64, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38229086

RESUMEN

BACKGROUND: Anti-fat attitudes and weight-based discrimination are prevalent in healthcare settings and among healthcare practitioners and clinical trainees, and can result in immense harm to patients. There is increasing recognition that anti-fat bias in healthcare is a critical issue that must be addressed, but there is a dearth of evidence demonstrating sustained attitude and behavioural change among clinicians, illustrating a need for more innovative educational approaches and rigorous evaluation. We describe the co-design and delivery of a narrative-based continuing professional development curriculum aimed at raising awareness of weight-based bias and stigma. METHODS: Our research team of lived experience educators, clinicians and researchers collaboratively developed a series of seven podcast episodes comprised of narrative descriptions of lived experiences with and impacts of weight bias, stigma and discrimination in healthcare settings, as well as a post-podcast workshop to facilitate reflection and discussion between participants. The curriculum was piloted among 20 clinicians practicing at a large urban hospital in Mississauga, Canada. We explored feasibility, acceptability and learning impact by analyzing responses to questionnaires completed following each podcast episode and responses shared during the workshops and follow-up feedback sessions. RESULTS: We observed high acceptability and feasibility of the curriculum. Participants experienced the podcast as a practical and convenient learning format and the workshop as a valuable opportunity to collectively debrief and reflect. The learning impact of the curriculum was strong; participants described a range of emotions elicited by the podcasts, engaged in self-reflection, and expressed a desire to modify clinical approaches. Barriers to the application of learnings identified by participants include pervasiveness of the use of body mass index (BMI) as an indicator of risk and a criterion for referral; discomfort with difficult conversations; prevalent biomedical understandings about the association between weight and health; and clinicians' defensiveness. CONCLUSION: This pilot study yielded promising findings and demonstrated potential impact on weight bias and stigma among healthcare providers. Necessary next steps include conducting larger scale, rigorous evaluations of the curriculum among broader populations, both health professions trainees and current healthcare providers.


Asunto(s)
Atención a la Salud , Estigma Social , Humanos , Proyectos Piloto , Actitud , Curriculum
3.
Ann Neurol ; 95(2): 347-361, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37801480

RESUMEN

OBJECTIVE: This study was undertaken to examine averted stroke in optimized stroke systems. METHODS: This secondary analysis of a multicenter trial from 2014 to 2020 compared patients treated by mobile stroke unit (MSU) versus standard management. The analytical cohort consisted of participants with suspected stroke treated with intravenous thrombolysis. The main outcome was a tissue-defined averted stroke, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis and no acute infarction/hemorrhage on imaging. An additional outcome was stroke with early symptom resolution, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis. RESULTS: Among 1,009 patients with a median last known well to thrombolysis time of 87 minutes, 159 (16%) had tissue-defined averted stroke and 276 (27%) had stroke with early symptom resolution. Compared with standard management, MSU care was associated with more tissue-defined averted stroke (18% vs 11%, adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.13-2.98) and stroke with early symptom resolution (31% vs 21%, aOR = 1.74, 95% CI = 1.12-2.61). The relationships between thrombolysis treatment time and averted/early recovered stroke appeared nonlinear. Most models indicated increased odds for stroke with early symptom resolution but not tissue-defined averted stroke with earlier treatment. Additionally, younger age, female gender, hyperlipidemia, lower National Institutes of Health Stroke Scale, lower blood pressure, and no large vessel occlusion were associated with both tissue-defined averted stroke and stroke with early symptom resolution. INTERPRETATION: In optimized stroke systems, 1 in 4 patients treated with thrombolysis recovered within 24 hours and 1 in 6 had no demonstrable brain injury on imaging. ANN NEUROL 2024;95:347-361.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Humanos , Femenino , Activador de Tejido Plasminógeno/uso terapéutico , Fibrinolíticos/uso terapéutico , Estudios Prospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/complicaciones , Hemorragia/complicaciones , Terapia Trombolítica/métodos , Resultado del Tratamiento , Isquemia Encefálica/tratamiento farmacológico
4.
Metabolites ; 13(7)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37512508

RESUMEN

Dietary flavanols are known for disease preventative properties but are often poorly absorbed. Gut microbiome flavanol metabolites are more bioavailable and may exert protective activities. Using metabolite mixtures extracted from the urine of rats supplemented with flavanols and treated with or without antibiotics, we investigated their effects on INS-1 832/13 ß-cell glucose stimulated insulin secretion (GSIS) capacity. We measured insulin secretion under non-stimulatory (low) and stimulatory (high) glucose levels, insulin secretion fold induction, and total insulin content. We conducted treatment-level comparisons, individual-level dose responses, and a responder vs. non-responder predictive analysis of metabolite composition. While the first two analyses did not elucidate treatment effects, metabolites from 9 of the 28 animals demonstrated significant dose responses, regardless of treatment. Differentiation of responders vs. non-responder revealed that levels of native flavanols and valerolactones approached significance for predicting enhanced GSIS, regardless of treatment. Although treatment-level patterns were not discernable, we conclude that the high inter-individual variability shows that metabolite bioactivity on GSIS capacity is less related to flavanol supplementation or antibiotic treatment and may be more associated with the unique microbiome or metabolome of each animal. These findings suggest flavanol metabolite activities are individualized and point to the need for personalized nutrition practices.

5.
Int J Stroke ; 18(10): 1209-1218, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37337357

RESUMEN

BACKGROUND: Few data exist on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials. A recent trial of mobile stroke units (MSUs) demonstrated faster treatment and improved outcomes, and included PD patients. AIM: To determine outcomes with tissue plasminogen activator (tPA), and benefit of MSU versus management by emergency medical services (EMS), for PD patients. METHODS: Primary outcomes were utility-weighted modified Rankin Scale (uw-mRS). Linear and logistic regression models compared outcomes in patients with versus without PD, and PD patients treated by MSU versus standard management by EMS. Time metrics, safety, quality of life, and health-care utilization were compared. RESULTS: Of the 1047 tPA-eligible ischemic stroke patients, 254 were with PD (baseline mRS 2-5) and 793 were without PD (baseline mRS 0-1). Although PD patients had worse 90-day uw-mRS, higher mortality, more health-care utilization, and worse quality of life than non-disabled patients, 53% returned to at least their baseline mRS, those treated faster had better outcome, and there was no increased bleeding risk. Comparing PD patients treated by MSU versus EMS, 90-day uw-mRS was 0.42 versus 0.36 (p = 0.07) and 57% versus 46% returned to at least their baseline mRS. There was no interaction between disability status and MSU versus EMS group assignment (p = 0.67) for 90-day uw-mRS. CONCLUSION: PD did not prevent the benefit of faster treatment with tPA in the BEST-MSU study. Our data support inclusion of PD patients in the MSU management paradigm.


Asunto(s)
Servicios Médicos de Urgencia , Accidente Cerebrovascular , Humanos , Fibrinolíticos/uso terapéutico , Calidad de Vida , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento , Ensayos Clínicos como Asunto
6.
R Soc Open Sci ; 10(3): 221386, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36968235

RESUMEN

Variation and disparity in resource access between individuals in an animal population within human-dominated landscapes require attention as artificial selection processes may be at work. Independent, recreational human-wildlife feeding interactions constitute an increasingly prevalent, yet understudied, food resource for birds and mammals living in our cities. However, only a limited number of risk-taking individuals may access it. Using urban fallow deer as our model species, we hypothesized that if these interactions result in positive effects for the engaging individual, e.g. increased milk quality and yield, then this would result in the increased growth rates of their offspring. Alternatively, if these individuals were prioritizing investing time in engagement with humans, resulting in decreased maternal care, then this would result in slower growth rates in their offspring. We found that the offspring of those females that regularly interacted with humans displayed significantly faster growth rates than their risk-adverse counterparts. This advantage for fearless mothers in terms of boosted neonatal growth rates could be mirrored in birds accessing garden feeders, seagulls or pigeons utilizing urban resources, or seals approaching city harbours. Here, we add a new piece to the complex puzzle of how humans are impacting wildlife living within human-dominated landscapes.

7.
Curr Dev Nutr ; 6(10): nzac105, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36204330

RESUMEN

Background: Purified diets (PDs) contain refined ingredients with one main nutrient, allowing for greater control relative to grain-based diets (GBDs), which contain unrefined grains and animal byproducts. Traditional PDs like the American Institute of Nutrition (AIN)-76A (76A) and AIN-93G (93G) can negatively impact metabolic and gut health when fed long term, in part due to lower total fiber, no soluble fiber, and higher sucrose content. Objective: Two studies were conducted to determine how PDs with reduced sucrose and increased fiber (soluble and insoluble) influence metabolic and gut health in mice compared with traditional AIN PDs or GBDs. Methods: In study 1, C57Bl/6N mice (n = 75) consumed a GBD [LabDiet 5002 (5002)], 76A, 93G, or 2 PDs with reduced sucrose and higher fiber for 88 d. Body composition and metabolic parameters were assessed. In study 2, C57Bl/6N mice (n = 54) consumed either 2 GBDs (LabDiet 5001 or 5002) or PDs with different types/levels of fiber for 14 d. Microbiome alterations and predicted functional metagenomic changes were measured. Results: The PD with 75 g cellulose and 25 g inulin per 4084 kcals marginally influenced body weight and adiposity, but improved glucose tolerance relative to 93G (P = 0.0131) and 76A (P = 0.0014). Cecal and colonic weights were lower in mice fed cellulose-based PDs compared with those fed GBDs and soluble-fiber PDs. Soluble-fiber PDs reduced alpha diversity and showed similar beta diversity, which differed from cellulose-based PDs and GBDs. Certain genera associated with improved gut health such as Bifidobacteria and Akkermansia were significantly elevated by soluble-fiber PDs (P ≤ 0.01). Metabolic pathways related to carbohydrate and fatty acid metabolism were affected by PDs. Conclusions: PDs formulated with lower sucrose and increased fiber content, particularly soluble fiber, blunted elevations in metabolic parameters and favorably impacted the microbiota and metagenome in C57BL/6N mice.

8.
Am J Mens Health ; 16(5): 15579883221123853, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36121234

RESUMEN

It is important to understand the role of social determinants, such as gender, in suicidal ideation. This study examined whether conformity to specific masculine norms, particularly high self-reliance and emotional self-control, moderated the relationship between psychological distress and suicidal ideation for men. The other norms explored were those pertaining to behavioral-emotional or social hierarchy status aspects of masculinity, and whether they moderated the psychological distress-suicidal ideation relationship for men and women. The Conformity to Masculine Norms Inventory, the Kessler Psychological Distress Scale, and the Suicidal Ideation Attributes Scale were administered to an Australian community sample in an online survey (n = 486). As predicted, higher psychological distress was associated with higher suicidal ideation. Self-reliance enhanced the relationship and was the only moderator among men. High self-reliance levels might be an important indicator of risk, which can be used when assessing and working with men who are hesitant to openly discuss suicidal ideation with clinicians. For female participants, higher endorsement of behavioral-emotional norms and lower conformity to social hierarchy status norms appear to increase suicide risk in the presence of psychological distress. Our findings suggest that high self-reliance is of particular concern for men experiencing psychological distress. It is also important to consider the roles of masculine norm endorsement in the psychological distress-suicidal ideation relationship among women.


Asunto(s)
Distrés Psicológico , Ideación Suicida , Australia , Femenino , Humanos , Masculino , Masculinidad , Violencia
9.
R Soc Open Sci ; 9(9): 220578, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36147938

RESUMEN

Recent debate has focused on whether variation in personality primarily reflects variation in resource allocation or resource acquisition of individuals. These two mechanisms predict different relationships between personality and survival. If personality mainly reflects variation in resource allocation, then bold (i.e. risk-taking) individuals are expected to live shorter lives, whereas the opposite pattern is expected with resource acquisition. Here we studied the relationship between neonate personality and early-life survival in 269 juveniles of a population of fallow deer (Dama dama). We found that bolder individuals paid no apparent survival cost. Interestingly, among-individual differences in the physiological response at capture (heart rates, which covary with the behavioural response, i.e. latency to leave) were linked to survival, where individuals with lower heart rates when handled by humans had a higher probability of early-life survival. This suggests that bolder individuals may be of higher state than their shyer counterparts. As the first study linking neonate personality to survival in a free-ranging mammal, we provide novel insights into drivers behind early-life individual variation.

10.
J Anim Ecol ; 91(9): 1892-1905, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35927829

RESUMEN

The artificial selection of traits in wildlife populations through hunting and fishing has been well documented. However, despite their rising popularity, the role that artificial selection may play in non-extractive wildlife activities, for example, recreational feeding activities, remains unknown. If only a subset of a population takes advantage of human-wildlife feeding interactions, and if this results in different fitness advantages for these individuals, then artificial selection may be at work. We have tested this hypothesis using a wild fallow deer population living at the edge of a capital city as our model population. In contrast to previous assumptions on the randomness of human-wildlife feeding interactions, we found that a limited non-random portion of an entire population is continuously engaging with people. We found that the willingness to beg for food from humans exists on a continuum of inter-individual repeatable behaviour; which ranges from risk-taking individuals repeatedly seeking and obtaining food, to shyer individuals avoiding human contact and not receiving food at all, despite all individuals having received equal exposure to human presence from birth and coexisting in the same herds together. Bolder individuals obtain significantly more food directly from humans, resulting in early interception of food offerings and preventing other individuals from obtaining supplemental feeding. Those females that beg consistently also produce significantly heavier fawns (300-500 g heavier), which may provide their offspring with a survival advantage. This indicates that these interactions result in disparity in diet and nutrition across the population, impacting associated physiology and reproduction, and may result in artificial selection of the begging behavioural trait. This is the first time that this consistent variation in behaviour and its potential link to artificial selection has been identified in a wildlife population and reveals new potential effects of human-wildlife feeding interactions in other species across both terrestrial and aquatic habitats.


Asunto(s)
Animales Salvajes , Ciervos , Animales , Dieta/veterinaria , Femenino , Humanos , Fenotipo , Reproducción
11.
Vet Sci ; 9(2)2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35202326

RESUMEN

Rumen studies have focused almost exclusively on livestock species under strictly regimented diets. This means that the ruminal condition of free-living and free-feeding wildlife remains practically unstudied. Urea nitrogen salvaging, a process by which urea is passed into the rumen, to both provide a valuable source of nitrogen for bacterial growth and to buffer the potentially harmful acidic effects of bacterial short chain fatty acids, has remained unexplored in wild ruminants, such as deer. UT-B2 transporters are the key proteins reported to facilitate the transepithelial ruminal urea transport. In this study, we investigate the expression, abundance and localisation of urea transporters in the rumen of a semi-wild fallow deer (Dama dama) population. Physical measurements confirmed that males had larger rumen than females, while adults had longer papillae than juveniles. Initial RT-PCR experiments confirmed the expression of UT-B2, while immunolocalisation studies revealed that strong UT-B staining was present in the stratum basale of deer rumen. Western blotting analysis demonstrated that a 50 kDa UT-B2 protein was significantly more abundant in adult females compared to adult males. This study confirms the presence of UT-B2 urea transporters in deer rumen and suggests that sex-related differences occur, bringing new insight into our understanding of rumen physiology.

12.
Nutr Cancer ; 74(1): 194-210, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33522303

RESUMEN

Flavanols are metabolized by the gut microbiota to bioavailable metabolites, and the absorbed fraction is excreted primarily via urine. Uroepithelial cells are thus a potential site of activity due to exposure to high concentrations of these compounds. Chemoprevention by flavanols may be partly due to these metabolites. In Vitro work in this area relies on a limited pool of commercially available microbial metabolites, and little has been done in bladder cancer. The impact of physiologically relevant mixtures of flavanols and their metabolites remains unknown. Rats were fed various flavanols and urine samples, approximating the bioavailable metabolome, were collected. Urines were profiled by UPLC-MS/MS, and their anti-proliferative activities were assayed In Vitro in four bladder cancer models. Significant interindividual variability was observed for composition and proliferation. Microbial metabolite concentrations (valerolactones, phenylalkyl acids and hippuric acids) were positively associated with reduced bladder cancer proliferation In Vitro, while native flavanols were poorly correlated with activity. These results suggest that microbial metabolites may be responsible for chemoprevention in uroepithelial cells following flavanol consumption. This highlights the potential to use individual genetics and microbial metabotyping to design personalized dietary interventions for cancer prevention and/or adjuvant therapy to reduce bladder cancer incidence and improve outcomes.


Asunto(s)
Microbioma Gastrointestinal , Neoplasias de la Vejiga Urinaria , Animales , Cromatografía Liquida , Polifenoles/análisis , Ratas , Espectrometría de Masas en Tándem , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
13.
N Engl J Med ; 385(11): 971-981, 2021 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-34496173

RESUMEN

BACKGROUND: Mobile stroke units (MSUs) are ambulances with staff and a computed tomographic scanner that may enable faster treatment with tissue plasminogen activator (t-PA) than standard management by emergency medical services (EMS). Whether and how much MSUs alter outcomes has not been extensively studied. METHODS: In an observational, prospective, multicenter, alternating-week trial, we assessed outcomes from MSU or EMS management within 4.5 hours after onset of acute stroke symptoms. The primary outcome was the score on the utility-weighted modified Rankin scale (range, 0 to 1, with higher scores indicating better outcomes according to a patient value system, derived from scores on the modified Rankin scale of 0 to 6, with higher scores indicating more disability). The main analysis involved dichotomized scores on the utility-weighted modified Rankin scale (≥0.91 or <0.91, approximating scores on the modified Rankin scale of ≤1 or >1) at 90 days in patients eligible for t-PA. Analyses were also performed in all enrolled patients. RESULTS: We enrolled 1515 patients, of whom 1047 were eligible to receive t-PA; 617 received care by MSU and 430 by EMS. The median time from onset of stroke to administration of t-PA was 72 minutes in the MSU group and 108 minutes in the EMS group. Of patients eligible for t-PA, 97.1% in the MSU group received t-PA, as compared with 79.5% in the EMS group. The mean score on the utility-weighted modified Rankin scale at 90 days in patients eligible for t-PA was 0.72 in the MSU group and 0.66 in the EMS group (adjusted odds ratio for a score of ≥0.91, 2.43; 95% confidence interval [CI], 1.75 to 3.36; P<0.001). Among the patients eligible for t-PA, 55.0% in the MSU group and 44.4% in the EMS group had a score of 0 or 1 on the modified Rankin scale at 90 days. Among all enrolled patients, the mean score on the utility-weighted modified Rankin scale at discharge was 0.57 in the MSU group and 0.51 in the EMS group (adjusted odds ratio for a score of ≥0.91, 1.82; 95% CI, 1.39 to 2.37; P<0.001). Secondary clinical outcomes generally favored MSUs. Mortality at 90 days was 8.9% in the MSU group and 11.9% in the EMS group. CONCLUSIONS: In patients with acute stroke who were eligible for t-PA, utility-weighted disability outcomes at 90 days were better with MSUs than with EMS. (Funded by the Patient-Centered Outcomes Research Institute; BEST-MSU ClinicalTrials.gov number, NCT02190500.).


Asunto(s)
Ambulancias , Servicios Médicos de Urgencia , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Unidades Móviles de Salud , Tiempo de Tratamiento , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , Evaluación de la Discapacidad , Femenino , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X
14.
Physiol Rep ; 9(16): e14970, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34405585

RESUMEN

Gut bacteria release trimethylamine (TMA) from dietary substrates. TMA is absorbed and is subsequently oxidized in the liver to produce trimethylamine N-oxide (TMAO). Plasma TMAO levels are positively correlated with risk for type 2 diabetes (T2D) and cardiovascular disease (CVD). High-fat diet (HFD) consumption has been reported to increase fasting and postprandial TMAO in sedentary individuals. However, whether the increase in TMAO with consumption of an HFD is observed in endurance-trained males is unknown. Healthy, sedentary (n = 17), and endurance-trained (n = 7) males consumed a 10-day eucaloric diet comprised of 55% carbohydrate, 30% total fat, and <10% saturated fat prior to baseline testing. Blood samples were obtained in a fasted state and for a 4-hour high-fat challenge (HFC) meal at baseline and then again following 5-day HFD (30% carbohydrate, 55% total fat, and 25% saturated fat). Plasma TMAO and TMA-moiety (choline, betaine, L-carnitine) concentrations were measured using isocratic ultraperformance liquid chromatography-tandem mass spectrometry. Age (23 ±3 vs. 22 ± 2 years) and body mass index (23.0 ± 3.0 vs. 23.5 ± 2.1 kg/m2 ) were similar (both p > 0.05) in the sedentary and endurance-trained group, respectively. VO2max was significantly higher in the endurance-trained compared with sedentary males (56.7 ± 8.2 vs. 39.9 ± 6.0 ml/kg/min). Neither the HFC nor the HFD evoked a detectable change in plasma TMAO (p > 0.05) in either group. Future studies are needed to identify the effects of endurance training on TMAO production.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Grasas de la Dieta/metabolismo , Entrenamiento Aeróbico , Ayuno/metabolismo , Metilaminas/sangre , Adolescente , Adulto , Factores de Riesgo Cardiometabólico , Humanos , Masculino , Periodo Posprandial , Conducta Sedentaria
15.
J Nutr Biochem ; 87: 108521, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33039581

RESUMEN

Significant evidence suggests protective effects of flavonoids against obesity in animal models, but these often do not translate to humans. One explanation for this disconnect is use of a few mouse strains (notably C57BL/6 J) in obesity studies. Obesity is a multifactorial disease. The underlying causes are not fully replicated by the high-fat C57BL/6 J model, despite phenotypic similarities. Furthermore, the impact of genetic factors on the activities of flavonoids is unknown. This study was designed to explore how diverse mouse strains respond to diet-induced obesity when fed a representative flavonoid. A subset of Collaborative Cross founder strains (males and females) were placed on dietary treatments (low-fat, high-fat, high-fat with quercetin, high-fat with quercetin and antibiotics) longitudinally. Diverse responses were observed across strains and sexes. Quercetin appeared to moderately blunt weight gain in male C57 and both sexes of 129S1/SvImJ mice, and slightly increased weight gain in female C57 mice. Surprisingly, quercetin dramatically blunted weight gain in male, but not female, PWK/PhJ mice. For female mice, quercetin blunted weight gain (relative to the high-fat phase) in CAST/PhJ, PWK/EiJ and WSB/EiJ mice compared to C57. Antibiotics did not generally result in loss of protective effects of quercetin. This highlights complex interactions between genetic factors, sex, obesity stimuli, and flavonoid intake, and the need to move away from single inbred mouse models to enhance translatability to diverse humans. These data justify use of genetically diverse Collaborative Cross and Diversity Outbred models which are emerging as invaluable tools in the field of personalized nutrition.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Ratones de Colaboración Cruzada/genética , Obesidad/tratamiento farmacológico , Obesidad/genética , Quercetina/uso terapéutico , Animales , Ratones de Colaboración Cruzada/fisiología , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Femenino , Variación Genética , Masculino , Obesidad/etiología , Factores Sexuales
16.
Neurology ; 96(6): e853-e865, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33219142

RESUMEN

OBJECTIVE: To explore the clinical efficacy and safety of subcutaneous (SC) rozanolixizumab, an anti-neonatal Fc receptor humanized monoclonal antibody, in patients with generalized myasthenia gravis (gMG). METHODS: In this phase 2a, randomized, double-blind, placebo-controlled, 2-period, multicenter trial (NCT03052751), patients were randomized (1:1) in period 1 (days 1-29) to 3 once-weekly (Q1W) SC infusions of rozanolixizumab 7 mg/kg or placebo. In period 2 (days 29-43), patients were re-randomized to either rozanolixizumab 7 mg/kg or 4 mg/kg (3 Q1W SC infusions), followed by an observation period (days 44-99). Primary endpoint was change from baseline to day 29 in Quantitative Myasthenia Gravis (QMG) score. Secondary endpoints were change from baseline to day 29 in MG-Activities of Daily Living (MG-ADL) and MG-Composite (MGC) scores and safety. RESULTS: Forty-three patients were randomized (rozanolixizumab 21, placebo 22 [period 1]). Least squares (LS) mean change from baseline to day 29 for rozanolixizumab vs placebo was as follows: QMG (LS mean -1.8 vs -1.2, difference -0.7, 95% upper confidence limit [UCL] 0.8; p = 0.221; not statistically significant), MG-ADL (LS mean -1.8 vs -0.4, difference -1.4, 95% UCL -0.4), and MGC (LS mean -3.1 vs -1.2, difference -1.8, 95% UCL 0.4) scores. Efficacy measures continued to improve with rozanolixizumab 7 mg/kg in period 2. The most common adverse event in period 1 was headache (rozanolixizumab 57%, placebo 14%). CONCLUSION: Whereas change from baseline in QMG was not statistically significant, the data overall suggest rozanolixizumab may provide clinical benefit in patients with gMG and was generally well tolerated. Phase 3 evaluation is ongoing (NCT03971422). CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for patients with gMG, rozanolixizumab is well-tolerated, but did not significantly improve QMG score.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Inmunosupresores/farmacología , Miastenia Gravis/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Método Doble Ciego , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad
17.
J Agric Food Chem ; 68(46): 13257-13266, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-32689794

RESUMEN

This study assessed the impact of caffeic and ferulic acid complexation with maize amylopectin or potato starch on glycemic parameters. In comparison to starch-phenolic mixtures, starch-phenolic complexes resulted in significant modification of phenolic bioaccessibility and cellular uptake (p < 0.05). In addition, glucose release from in vitro digestion of starch was modestly reduced in the complexes compared to native starch alone (21.2-26.8 versus 29.8-30.5 mM). Furthermore, intestinal glucose transport, assessed in Caco-2 cell monolayers, was not affected by the presence of complexes (82.4-124 versus 100% at 90 min). However, a reduced glycemic response was evident in a Wistar rat model, with significant reduction in 240 min of blood glucose area under the curve following oral administration of the potato starch-ferulic acid complex compared to native potato starch (26 170 ± 556 versus 28 951 ± 486 mg min dL-1; p < 0.001). These alterations were attributed to complexation-induced resistant starch formation and phenolic entrapment, providing an alternative mechanistic approach to modulate glycemic properties of starch-based foods.


Asunto(s)
Hidroxibenzoatos/metabolismo , Fenoles/metabolismo , Solanum tuberosum/metabolismo , Almidón/metabolismo , Zea mays/metabolismo , Animales , Glucemia/metabolismo , Células CACO-2 , Índice Glucémico , Humanos , Intestinos , Masculino , Ratas , Ratas Wistar , Almidón/análisis
18.
Appetite ; 144: 104442, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31494153

RESUMEN

Bitterness and astringency (dryness) are characteristic sensory attributes of flavanol-rich foods. The degree of polymerization (DP) of flavanols influences their bitter and astringent sensations. Smaller DP compounds can enter the papillae on the tongue, eliciting a bitter response. Larger DP compounds are sterically inhibited from entering papillae and instead interact with oral proteins, cause precipitation, and elicit astringent sensations. Previous research has indicated that bitterness preference is related to health status, density of fungiform papillae on the tongue, and sensitivity to bitter compounds such as 6-n-propyl-thiouracil (PROP). The purpose of this study was to examine trends in liking, bitterness intensity, and astringency intensity of wine-like products with flavanols of different DP using a consumer sensory panel. Participants (n = 102) were segmented by phenotypes: body fat percentage (BF%), body mass index (BMI), PROP sensitivity, and stated bitter food preference. Differences in wine liking, perceived bitterness intensity, and astringency intensity were observed between three model wine samples of varying flavanol mean degrees of polymerization (mDP, i.e. the average size (polymer length) of flavanol compounds in a mixture). Specifically, with increased mDP, overall liking and bitterness liking decreased, with concurrent increased perception of bitterness and astringency intensity. Greater differences between phenotypes were observed when participants were segmented by BF% and BMI classification, than when segmented by PROP sensitivity classification. Reduced ability to detect differences in bitterness and astringency were noted in participants of higher weight status. Overall, these data suggest that weight status in adults is a greater predictor of liking of flavanol-rich foods than bitterness sensitivity (as determined by PROP classification), and that reduced perception of bitterness and astringency associated with weight gain may impact selection and preference for these foods.


Asunto(s)
Composición Corporal/fisiología , Preferencias Alimentarias/efectos de los fármacos , Polifenoles/administración & dosificación , Gusto/efectos de los fármacos , Vino/análisis , Tejido Adiposo , Adulto , Índice de Masa Corporal , Peso Corporal/fisiología , Femenino , Preferencias Alimentarias/fisiología , Humanos , Masculino , Persona de Mediana Edad , Polimerizacion , Propiltiouracilo/administración & dosificación , Gusto/fisiología , Papilas Gustativas/efectos de los fármacos , Umbral Gustativo/efectos de los fármacos , Adulto Joven
19.
Antioxidants (Basel) ; 8(12)2019 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-31835748

RESUMEN

Raw cocoa beans were processed to produce cocoa powders with different combinations of fermentation (unfermented, cool, or hot) and roasting (not roasted, cool, or hot). Cocoa powder extracts were characterized and assessed for α-glucosidase inhibitory activity in vitro. Cocoa processing (fermentation/roasting) contributed to significant losses of native flavanols. All of the treatments dose-dependently inhibited α-glucosidase activity, with cool fermented/cool roasted powder exhibiting the greatest potency (IC50: 68.09 µg/mL), when compared to acarbose (IC50: 133.22 µg/mL). A strong negative correlation was observed between flavanol mDP and IC50, suggesting flavanol polymerization as a marker of enhanced α-glucosidase inhibition in cocoa. Our data demonstrate that cocoa powders are potent inhibitors of α-glucosidase. Significant reductions in the total polyphenol and flavanol concentrations induced by processing do not necessarily dictate a reduced capacity for α-glucosidase inhibition, but rather these steps can enhance cocoa bioactivity. Non-traditional compositional markers may be better predictors of enzyme inhibitory activity than cocoa native flavanols.

20.
J Food Sci ; 84(8): 2147-2158, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31313833

RESUMEN

Multiple analytical methods are used for quantification of total polyphenols and total flavanols in fruit juices and beverages. Four methods were evaluated in this study: Folin-Ciocalteu (F-C), Lowenthal permanganate (L-P), 4-dimethylaminocinnamaldehyde (DMAC), and the bovine serum albumin (BSA) precipitation method. Method validation parameters, including working range, limit of detection, limit of quantitation, precision (repeatability), accuracy, and specificity, were assessed and compared. The F-C method was not specific to polyphenols, and the L-P method had the widest working range but lacked accuracy. The DMAC method was the most specific to flavanols, and the BSA method was not suitable for quantification of smaller flavanols, such as catechin and epicatechin. Quantitative performance was evaluated using commercial fruit juice samples (n = 14), apple juice samples of different cultivars (n = 22), and commercial ciders (n = 17). In general, the L-P titration method and DMAC method resulted in higher quantitative values than the F-C method and BSA precipitation method, respectively. However, ratios of results obtained by the L-P and F-C method ranged from 1 to 28, and ratios of results obtained by the DMAC and BSA precipitation method ranged from <1 to 280. This tremendous variation is likely due to variation in polyphenol composition and sample matrix. This information provides perspective for comparison of results obtained through these different methods, and a basis for choosing the most appropriate analytical method for quantification of polyphenols to address a specific research question when working with commercial fruit juice, apple juice from different apple cultivars, and commercial ciders. PRACTICAL APPLICATION: This study compared results obtained when four common polyphenol quantification methods were applied to a diverse selection of fruit juices and beverages with distinct polyphenol composition and sample matrix. The matrix and polyphenol composition of the samples significantly influenced the results. Our findings can help manufacturers of fruit-based products choose the most appropriate analytical method for polyphenol quantification as part of a quality assurance program or to convey information on dietary polyphenol content to consumers. An assessment of analytical method validation parameters is provided for each of the four methods, which will help users of these methods to understand their limitations.


Asunto(s)
Flavanonas/análisis , Análisis de los Alimentos/métodos , Jugos de Frutas y Vegetales/análisis , Polifenoles/análisis , Frutas/química , Malus/química
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