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71.
Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3 (HN: 2 × 70 mL BJ/day) (2) medium-NO3 (MN: 70 mL BJ/day), (3) low-NO3 (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3 intake, and by measuring NO3 and NO2 concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3 dose and the increase in plasma and urinary NO3 concentration (R2 = 0.71, p < 0.001 and R2 = 0.46 p < 0.001, respectively), but relationships between NO3 dose and changes in salivary NO3 and NO2 were non-linear (R2 = 0.35, p = 0.002 and R2 = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.  相似文献   
72.
Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours.  相似文献   
73.
BackgroundPerson‐centred care implies a change in interaction between care professionals and patients where patients are not passive recipients but co‐producers of care. The interactional practices of person‐centred care remain largely unexplored.ObjectiveThis study focuses on the analysis of disagreements, which are described as an important part in the co‐production of knowledge in interaction.DesignA qualitative exploratory study using conversation analysis.Setting and participantsData were collected from a nurse‐led person‐centred intervention in a hospital outpatient setting. Interactions between adult patients with irritable bowel syndrome (n = 17) and a registered nurse were audio‐recorded. COREQ guidelines were applied.ResultsDisagreements were found after demonstration of the nurse''s or patients’ respective professional or personal knowledge. Disagreements were also evident when deciding on strategies for self‐management. Although negotiations between opposing views of the nurse and patient were seen as important, the patient generally claimed final authority both in knowing how IBS is perceived and in the right to choose self‐management strategies. The nurse generally oriented towards patient authority, but instances of demonstration of nurse authority despite patient resistance were also found.Discussion and conclusionsThis study provides information on how co‐production of knowledge and decisions occur in the context of a person‐centred care intervention. Negotiations between nurse and patient views require a flexible approach to communication, adapting interaction to each context while bearing in mind the patients having the final authority. To facilitate co‐production, the patient''s role and responsibilities in interaction should be explicitly stated.  相似文献   
74.
The remodeling of the extracellular matrix is a central function in endochondral ossification and bone homeostasis. During secondary fracture healing, vascular invasion and bone growth requires the removal of the cartilage intermediate and the coordinate action of the collagenase matrix metalloproteinase (MMP)-13, produced by hypertrophic chondrocytes, and the gelatinase MMP-9, produced by cells of hematopoietic lineage. Interfering with these MMP activities results in impaired fracture healing characterized by cartilage accumulation and delayed vascularization. MMP-10, Stromelysin 2, a matrix metalloproteinase with high homology to MMP-3 (Stromelysin 1), presents a wide range of putative substrates identified in vitro, but its targets and functions in vivo and especially during fracture healing and bone homeostasis are not well defined. Here, we investigated the role of MMP-10 through bone regeneration in C57BL/6 mice. During secondary fracture healing, MMP-10 is expressed by hematopoietic cells and its maximum expression peak is associated with cartilage resorption at 14 days post fracture (dpf). In accordance with this expression pattern, when Mmp10 is globally silenced, we observed an impaired fracture-healing phenotype at 14 dpf, characterized by delayed cartilage resorption and TRAP-positive cell accumulation. This phenotype can be rescued by a non-competitive transplant of wild-type bone marrow, indicating that MMP-10 functions are required only in cells of hematopoietic linage. In addition, we found that this phenotype is a consequence of reduced gelatinase activity and the lack of proMMP-9 processing in macrophages. Our data provide evidence of the in vivo function of MMP-10 during endochondral ossification and defines the macrophages as the lead cell population in cartilage removal and vascular invasion. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Maternal obesity may lead to epigenetic alterations in the offspring and might thereby contribute to disease later in life. We investigated whether a lifestyle intervention in pregnant women with obesity is associated with epigenetic variation in cord blood and body composition in the offspring. Genome-wide DNA methylation was analyzed in cord blood from 208 offspring from the Treatment of Obese Pregnant women (TOP)-study, which includes pregnant women with obesity randomized to lifestyle interventions comprised of physical activity with or without dietary advice versus control subjects (standard of care). DNA methylation was altered at 379 sites, annotated to 370 genes, in cord blood from offspring of mothers following a lifestyle intervention versus control subjects (false discovery rate [FDR] <5%) when using the Houseman reference-free method to correct for cell composition, and three of these sites were significant based on Bonferroni correction. These 370 genes are overrepresented in gene ontology terms, including response to fatty acids and adipose tissue development. Offspring of mothers included in a lifestyle intervention were born with more lean mass compared with control subjects. Methylation at 17 sites, annotated to, for example, DISC1, GBX2, HERC2, and HUWE1, partially mediates the effect of the lifestyle intervention on lean mass in the offspring (FDR <5%). Moreover, 22 methylation sites were associated with offspring BMI z scores during the first 3 years of life (P < 0.05). Overall, lifestyle interventions in pregnant women with obesity are associated with epigenetic changes in offspring, potentially influencing the offspring’s lean mass and early growth.  相似文献   
78.
Atypical femur fractures (AFF) are a rare but serious complication of long-term bisphosphonate use. Although clearly defined by ASBMR criteria, a proportion of patients with AFFs may go unrecognized and the use of qualitative fracture criteria may lead to uncertainty in AFF diagnosis, with significant therapeutic implications. A score that rapidly and accurately identifies AFFs among subtrochanteric femur fractures using quantitative, measurable parameters is needed. In a retrospective cohort of 110 female patients presenting with AFFs or typical femur fractures (TFFs), multiple logistic regression and decision tree analysis were used to develop the Sydney AFF score. This score, based on demographic and femoral geometry variables, uses three dichotomized independent predictors and adds one point for each: (age ≤80 years) + (femoral neck width <37 mm) + (lateral cortical width at lesser trochanter ≥5 mm), (score, 0 to 3). In an independent validation set of 53 female patients at a different centre in Sydney, a score ≥2 demonstrated 73.3% sensitivity and 69.6% specificity for AFF (area under the receiver-operating characteristic curve [AUC] 0.775, SE 0.063) and remained independently associated with AFF after adjustment for bisphosphonate use. The Sydney AFF score provides a quantitative means of flagging female patients with atraumatic femur fractures who have sustained an AFF as opposed to a TFF. This distinction has clear management implications and may augment current ASBMR diagnostic criteria. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Domino liver transplantation (DLT) has been used widely in patients with hereditary amyloid transthyretin (ATTR) amyloidosis. New-onset polyneuropathy in recipients of DLT has been reported, but there are few cases of cardiac involvement reported. We aimed to perform a cross-sectional study for ATTR amyloidosis with cardiomyopathy (ATTR-CM) in DLT recipients. We evaluated 23 living DLT recipients a median of 9 years since DLT at 2 referral centers with a systematic cardiac evaluation, including bone scintigraphy. Median age was 72 years, 91% had hypertension, 35% had diabetes mellitus, 67% had chronic renal failure, and 8 patients (35%) developed new-onset polyneuropathy. Only 13% had a normal electrocardiogram and a normal echocardiography, and most of them showed some conduction disturbance or increase in left ventricular wall thickness, but only 1 patient with a Glu89Lys mutation developed ATTR-CM diagnosed by bone scintigraphy and endomyocardial biopsy. None of the recipients of a DLT with Val30Met mutation showed cardiac involvement by bone scintigraphy. In conclusion, DLT from Val30Met donors seems to be safe regarding the development of ATTR-CM. Evaluation of cardiomyopathy in DLT recipients is challenging due to concomitant comorbidities and in this context, bone scintigraphy can be helpful to evaluate ATTR-CM.  相似文献   
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