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61.

Background

Little is known about zinc intakes and status during complementary feeding. This is particularly true for baby-led approaches, which encourage infants to feed themselves from the start of complementary feeding, although self-feeding may restrict the intake of zinc-rich foods.

Objective

To determine the zinc intakes, sources, and biochemical zinc status of infants following Baby-Led Introduction to SolidS (BLISS), a modified version of Baby-Led Weaning (BLW), compared with traditional spoon-feeding.

Design

Secondary analysis of the BLISS randomized controlled trial.

Participants/setting

Between 2012 and 2014, 206 community-based participants from Dunedin, New Zealand were randomized to a Control or BLISS group.

Intervention

BLISS participants received eight study visits (antenatal to 9 months) providing education and support regarding BLISS (ie, infant self-feeding from 6 months with modifications to address concerns about iron, choking, and growth).

Main outcome measures

Dietary zinc intakes at 7 and 12 months (weighed 3-day diet records) and zinc status at 12 months (plasma zinc concentration).

Statistical analyses performed

Regression analyses were used to investigate differences in dietary intakes and zinc status by group, adjusted for maternal education and parity and infant age and sex.

Results

There were no significant differences in zinc intakes between BLISS and Control infants at 7 (median: 3.5 vs 3.5 mg/day; P=0.42) or 12 (4.4 vs 4.4 mg/day; P=0.86) months. Complementary food groups contributing the most zinc at 7 months were “vegetables” for Control infants, and “breads and cereals” for BLISS infants, then “dairy” for both groups at 12 months. There was no significant difference in mean±standard deviation plasma zinc concentration between the Control (62.8±9.8 μg/dL [9.6±1.5 μmol/L]) and BLISS (62.8±10.5 μg/dL [9.6±1.6 μmol/L]) groups (P=0.75).

Conclusions

BLISS infants achieved similar zinc intake and status to Control infants. However, the BLISS intervention was modified to increase iron intake, which may have improved zinc intake, so these results should not be generalized to infants following unmodified BLW.  相似文献   
62.
Prevalence of obesity, an established risk factor for many cancers, has increased dramatically over the past 50 years in the United States and across the globe. Relative to normoweight cancer patients, obese cancer patients often have poorer prognoses, resistance to chemotherapies, and are more likely to develop distant metastases. Recent progress on elucidating the mechanisms underlying the obesity?cancer connection suggests that obesity exerts pleomorphic effects on pathways related to tumor development and progression and, thus, there are multiple opportunities for primary prevention and treatment of obesity-related cancers. Obesity-associated alterations, including systemic metabolism, adipose inflammation, growth factor signaling, and angiogenesis, are emerging as primary drivers of obesity-associated cancer development and progression. These obesity-associated host factors interact with the intrinsic molecular characteristics of cancer cells, facilitating several of the hallmarks of cancer. Each is considered in the context of potential preventive and therapeutic strategies to reduce the burden of obesity-related cancers. In addition, this review focuses on emerging mechanisms behind the obesity?cancer link, as well as relevant dietary interventions, including calorie restriction, intermittent fasting, low-fat diet, and ketogenic diet, that are being implemented in preclinical and clinical trials, with the ultimate goal of reducing incidence and progression of obesity-related cancers.  相似文献   
63.
64.

Background

Malnutrition is a significant problem for hospitalized patients. However, the true prevalence of reported malnutrition diagnosis in real-world clinical practice is largely unknown. Using a large collaborative multi-institutional database, the rate of malnutrition diagnosis was assessed and used to assess institutional variables associated with higher rates of malnutrition diagnosis.

Objective

The aim of this study was to define the prevalence of malnutrition diagnosis reported among inpatient hospitalizations.

Design

The University Health System Consortium (Vizient) database was retrospectively reviewed for reported rates of malnutrition diagnosis.

Participants/setting

All adult inpatient hospitalization at 105 member institutions during fiscal years 2014 and 2015 were evaluated.

Main outcome measures

Malnutrition diagnosis based on the presence of an International Classification of Diseases-Ninth Revision diagnosis code.

Statistical analysis

Hospital volume and publicly available hospital rankings and patient satisfaction scores were obtained. Multiple regression analysis was performed to assess the association between these variables and reported rates of malnutrition.

Results

A total of 5,896,792 hospitalizations were identified from 105 institutions during the 2-year period. It was found that 292,754 patients (5.0%) had a malnutrition diagnosis during their hospital stay. By institution, median rate of malnutrition diagnosis during hospitalization was 4.0%, whereas the rate of severe malnutrition diagnosis was 0.9%. There was a statistically significant increase in malnutrition diagnosis from 4.0% to 4.9% between 2014 and 2015 (P<0.01). Institutional factors associated with increased diagnosis of malnutrition were higher hospital volume, hospital ranking, and patient satisfaction scores (P<0.01).

Conclusions

Missing a malnutrition diagnosis appears to be a universal issue because the rate of malnutrition diagnosis was consistently low across academic medical centers. Institutional variables were associated with the prevalence of malnutrition diagnosis, which suggests that institutional culture influences malnutrition diagnosis. Quality improvement efforts aimed at improved structure and process appear to be needed to improve the identification of malnutrition.  相似文献   
65.
66.

Background

Dietary supplement (DS) use is prevalent among the US Armed Forces personnel, but representative cross-service comparisons and characteristics of personnel using DSs are limited.

Objective

Examine DS use and characteristics associated with use in a representative sample of US Armed Forces personnel (Army, Navy, Air Force, Marine Corps, and Coast Guard) using data from the 2011 Department of Defense Survey of Health-Related Behaviors.

Design and participants

A stratified random sample of service members (SMs) was contacted and asked to complete a questionnaire assessing personal characteristics and DS use.

Results

Overall, 69% of the 39,877 SMs reported using DSs ≥1 time per week. The most commonly used DSs were multivitamin or multiminerals (50%), antioxidants (34%), individual vitamins or minerals (33%), bodybuilding supplements (27%), fish oils (26%), herbals (16%), and weight-loss supplements (16%). Multiple logistic regression indicated overall DS use was higher among women, those with higher educational levels, Marine Corps SMs, officers, those with higher body mass index, those engaged in greater physical activity and weight training, and people in weight control programs. DS use was lower when peer groups or leadership discouraged substance abuse.

Conclusions

DS use was considerably higher in the US Armed Forces compared with civilian populations, although many demographic and lifestyle factors associated with use were similar. Some categories of DSs extensively used by SMs such as bodybuilding supplements have been associated with adverse events. Discouraging substance abuse through peer groups and leadership actions may reduce use of unnecessary or dangerous DSs.  相似文献   
67.
The transdermal delivery of 2 fluorescent probes with similar molecular weight but different lipophilicity, into and through the skin from 2 commercially available transdermal bases, pluronic lecithin organogel, and Lipoderm® has been evaluated. First, in vitro penetration of fluorescein sodium and fluorescein (free acid) through porcine skin was evaluated. Retention and depth distribution profiles in skin were obtained by tape stripping and then followed by optical sectioning using multiphoton microscopy. The results showed that Lipoderm® led to an enhanced penetration of the hydrophilic compound, fluorescein sodium. For the lipophilic compound fluorescein (free acid), Lipoderm® performed similar to pluronic lecithin organogel base, where minimal drug was detected in either receptor phase. The skin retention and depth distribution results also showed that the hydrophilic fluorescein sodium had high skin retention with Lipoderm®, whereas fluorescein (free acid) had very low penetration and retention with increasing skin depth. Moreover, optical sectioning by multiphoton microscopy revealed an uneven distribution of probes across the skin in the x-y plane for both transdermal bases. This work showed that a hydrophilic compound has significantly increased skin penetration and retention when formulated with Lipoderm®, and the skin retention of the probe was the main determinant of its skin flux.  相似文献   
68.
69.
Nodular basal cell carcinoma is a deep skin lesion and one of the most common cancers. Conventional photodynamic therapy is limited to treatment of superficial skin lesions. The parenteral administration of near-IR preformed photosensitizers suffers from poor selectivity and may result in prolonged skin photosensitivity. Microneedles (MNs) can provide localized drug delivery to skin lesions. Intradermal delivery of the preformed near-IR photosensitizer; 5,10,15,20-tetrakis(2,6-difluoro-3-N-methylsulfamoylphenyl bacteriochlorin (Redaporfin?) using dissolving MN was successful in vitro and in vivo. MN demonstrated complete dissolution 30 min after skin application and showed sufficient mechanical strength to penetrate the skin to a depth of 450 μm. In vitro deposition studies illustrated that the drug was delivered and detected down to 5 mm in skin. In vivo biodistribution studies in athymic nude mice Crl:NU(NCr)-Foxn1nu showed both fast initial release and localized drug delivery. The MN-treated mice showed a progressive decrease in the fluorescence intensity at the application site over the 7-day experiment period, with the highest and lowest fluorescence intensities measured being 9.2 × 1010 ± 2.5 × 1010 and 3.8 × 109 ± 1.6 × 109 p/s, respectively. By day 7, there was some migration of fluorescence away from the site of initial MN application. However, the majority of the body surfaces showed fluorescence levels that were comparable to those seen in the negative control group. This work suggests utility for polymeric MN arrays in minimally invasive intradermal delivery to enhance photodynamic therapy of deep skin lesions.  相似文献   
70.
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.  相似文献   
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