¡Míranos! a Comprehensive Preschool Obesity Prevention Program in Low-Income Latino Children: One-year Results of a Clustered Randomized Controlled Trial.

OBJECTIVE: Test a culturally tailored obesity prevention intervention in low-income, minority preschool-age children. DESIGN: A three-group clustered randomized controlled trial. SETTING: Twelve Head Start Centers were randomly assigned to a center-based intervention, a combined center- and home-based intervention, or control using a 1:1:1 ratio. The center-based intervention modified center physical activity and nutrition policies, staff practices, and child behaviors, while the home-based intervention supported parents for obesity prevention at home. STUDY OUTCOMES: The primary endpoint was change in children's body mass index (BMI; kg/m2) at posttest immediately following completion of the 8-month intervention. Secondary endpoints included standardized scores for BMI (BMIz) and body weight (WAZ), and BMI percentiles (BMI pctl). PARTICIPANTS: Three-year-old children enrolled in Head Start in San Antonio, Texas, with written parent consent (N=325), 87% Latino; 57% female with mean age (SD) of 3.58 years (0.29). RESULTS: Change in BMI at posttest was 1.28 (0.97), 1.28 (0.87), and 1.41 (0.71) in the center+home-based intervention, center-based intervention, and control, respectively. There was no significant difference in BMI change between center+home-based intervention and control or center-based intervention and control at posttest. BMIz (adjusted difference -0.12 [95% CI, -0.24 to 0.01], p = .06) and WAZ (adjusted difference, -0.09 [-0.17 to -0.002], p = .04) were reduced for children in center+home-based intervention compared to control group. CONCLUSIONS: There was no reduction in BMI at posttest in children who received the intervention. Findings shed light on methodological challenges in childhood obesity research and offer future directions to explore health equity-oriented obesity prevention.

Study protocol for a cluster randomized controlled trial to test "¡Míranos! Look at Us, We Are Healthy!" - an early childhood obesity prevention program.

BACKGROUND: One in three Head Start children is either overweight or obese. We will test the efficacy of an early childhood obesity prevention program, "¡Míranos! Look at Us, We Are Healthy!" (¡Míranos!), which promotes healthy growth and targets multiple energy balance-related behaviors in predominantly Latino children in Head Start. The ¡Míranos! intervention includes center-based (policy changes, staff development, gross motor program, and nutrition education) and home-based (parent engagement/education and home visits) interventions to address key enablers and barriers in obesity prevention in childcare. In partnership with Head Start, we have demonstrated the feasibility and acceptability of the proposed interventions to influence energy balance-related behaviors favorably in Head Start children. METHODS: Using a three-arm cluster randomized controlled design, 12 Head Start centers will be randomly assigned in equal number to one of three conditions: 1) a combined center- and home-based intervention, 2) center-based intervention only, or 3) comparison. The interventions will be delivered by trained Head Start staff during the academic year. A total of 444 3-year-old children (52% females; n = 37 per center at baseline) in two cohorts will be enrolled in the study and followed prospectively 1 year post-intervention. Data collection will be conducted at baseline, immediately post-intervention, and at the one-year follow-up and will include height, weight, physical activity (PA) and sedentary behaviors, sleep duration and screen time, gross motor development, dietary intake and food and activity preferences. Information on family background, parental weight, PA- and nutrition-related practices and behaviors, PA and nutrition policy and environment at center and home, intervention program costs, and treatment fidelity will also be collected. DISCUSSION: With endorsement and collaboration of two local Head Start administrators, ¡Míranos!, as a culturally tailored obesity prevention program, is poised to provide evidence of efficacy and cost-effectiveness of a policy and environmental approach to prevent early onset of obesity in low-income Latino preschool children. ¡Míranos! can be disseminated to various organized childcare settings, as it is built on the Head Start program and its infrastructure, which set a gold standard for early childhood education, as well as current PA and nutrition recommendations for preschool children. TRIAL REGISTRATION: ClinicalTrials.Gov ( NCT03590834 ) July 18, 2018.

Comparison of DC Bead-irinotecan and DC Bead-topotecan drug eluting beads for use in locoregional drug delivery to treat pancreatic cancer.

DC Bead is a drug delivery embolisation system that can be loaded with doxorubicin or irinotecan for the treatment of a variety of liver cancers. In this study we demonstrate that the topoisomerase I inhibitor topotecan hydrochloride can be successfully loaded into the DC Bead sulfonate-modified polyvinyl alcohol hydrogel matrix, resulting in a sustained-release drug eluting bead (DEBTOP) useful for therapeutic purposes. The in vitro drug loading capacity, elution characteristics and the effects on mechanical properties of the beads are described with reference to our previous work with irinotecan hydrochloride (DEBIRI). Results showed that drug loading was faster when the solution was agitated compared to static loading and a maximum loading of ca. 40-45 mg topotecan in 1 ml hydrated beads was achievable. Loading the drug into the beads altered the size, compressibility moduli and colour of the bead. Elution was shown to be reliant on the presence of ions to perform the necessary exchange with the electrostatically bound topotecan molecules. Topotecan was shown by MTS assay to have an IC(50) for human pancreatic adenocarcinoma cells (PSN-1) of 0.22 and 0.27 microM compared to 28.1 and 19.2 microM for irinotecan at 48 and 72 h, respectively. The cytotoxic efficacy of DEBTOP on PSN-1 was compared to DEBIRI. DEPTOP loaded at 6 & 30 mg ml(-1), like its free drug form, was shown to be more potent than DEBIRI of comparable doses at 24, 48 & 72 h using a slightly modified MTS assay. Using a PSN-1 mouse xenograft model, DEBIRI doses of 3.3-6.6 mg were shown to be well-tolerated (even with repeat administration) and effective in reducing the tumour size. DEBTOP however, was lethal after 6 days at doses of 0.83-1.2 mg but demonstrated reasonable efficacy and tolerability (again with repeat injection possible) at 0.2-0.4 mg doses. Care must therefore be taken when selecting the dose of topotecan to be loaded into DC Bead given its greater potency and potential toxicity.

Synthesis and characterisation of cationically modified phospholipid polymers.

Phospholipid-like copolymers based on 2-(methacryloyloxyethyl) phosphorylcholine were synthesised using monomer-starved free radical polymerisation methods and incorporating cationic charge in the form of the choline methacrylate monomer in amounts varying from 0 to 30 wt%, together with a 5 wt% silyl cross-linking agent in order to render them water-insoluble once thermally cured. Characterisation using a variety of techniques including nuclear magnetic resonance spectroscopy, high-pressure liquid chromatography and gel permeation chromatography showed the cationic monomer did not interfere with the polymerisation and that the desired amount of charge had been incorporated. Gravimetric and differential scanning calorimetry methods were used to evaluate the water contents of polymer membranes cured at 70 degrees C, which was seen to increase with increasing cation content, producing materials with water contents ranging from 50% to 98%. Surface plasmon resonance indicated that the coatings swelled rapidly in water, the rate and extent of swelling increasing with increasing cation level. Dynamic contact angle showed that coatings of all the polymers possessed a hydrophobic surface when dry in air, characteristic of the alkyl chains expressed at the surface (>100 degrees advancing angle). Rearrangement of the hydrophilic groups to the surface occurred once wet, to produce highly wettable surfaces with a decrease in advancing angle with increasing cation content. Atomic force microscopy showed all polymer films to be smooth with no features in topographical or phase imaging. Mechanical properties of the dry films were also unaffected by the increase in cation content.

Drug loading and elution from a phosphorylcholine polymer-coated coronary stent does not affect long-term stability of the coating in vivo.

A drug eluting coronary stent was developed for use in preclinical and clinical trial evaluation. The stent was coated with a phosphorylcholine (PC)-based polymer coating containing the cell migration inhibitor batimastat. A pharmacokinetic study was conducted in a rabbit iliac model using (14)C-radiolabeled version of the drug; this showed the drug release to be first order with 94% of it being released within 28 days. Unloaded and drug-loaded stents were implanted in a porcine coronary artery model; a number were explanted at 5 days and scanning electron microscopy was used to show that the presence of the drug did not affect the rate of stent endothelialization. The remainder of the stents were removed after 6 months and the stents carefully removed from the arterial tissue. Fourier-transform infrared (FT-IR) spectroscopy (both attenuated total reflectance and microscopic imaging) was used to show the presence of the PC coating on control unloaded, drug-loaded and explanted stents, providing evidence that the coating was still present. This was further confirmed by use of atomic force microscopy (AFM) amplitude-phase, distance (a-p,d) curves which generated the characteristic traces of the PC coating. Further AFM depth-profiling techniques found that the thicknesses of the PC coatings on an control unloaded stent was 252+/-19 nm, on an control batimastat-loaded stent 906+/-224 nm and on an explanted stent 405+/-224 nm. The increase in thickness after the drug-loading process was a consequence of drug incorporation in the film, and the return to the unloaded dimensions for the explanted sample indicative of elution of the drug from the coating. The drug delivery PC coating was therefore found to be stable following elution of the drug and after 6 months implantation in vivo.

Comparative in vitro evaluation of microspherical embolisation agents.

This study describes the comparative performance of four commercially available microspherical embolisation products: Embosphere, Embogold, Contour SE and Bead Block. A series of in vitro evaluations were designed to assess the mechanical and biological characteristics of these biomaterials. Size distribution analysis revealed sieving techniques used to fractionate the embolics produced similar size distributions. The forces required to compress Embosphere, Embogold and Bead Block were in the range 21-27.5 kPa. Contour SE was significantly more compressible at approximately 5 kPa. However, recoverability of Contour SE required several minutes in contrast to the other products, a phenomenon attributed to its macroporous structure. When time taken to reach and remain in suspension was studied, results showed that the products quickly reached equilibrium with contrast agent. Bead Block was maintained in suspension for twice as long as the other products. Catheter deliverability was assessed and found to be dependent upon both microsphere and catheter, the best combination being Bead Block delivered via the Progreat catheter. Both the blood contacting SEM and plasma coagulation time showed none of the products were pro-thrombic or pro-coagulatory, each producing comparable results. Small differences in physical properties such as compressibility, could play an important role in delivery and effectiveness of vessel blockage. Currently all products are used routinely in clinical practice.