Physicochemical characterisation of fluids and soft foods frequently mixed with oral drug formulations prior to administration to children

Oral drug administration to children poses specific pharmaceutical challenges that are often not seen to the same extent in adults, and whose occurrence may also be age dependent. When an age-appropriate dosage form is not available, manipulation of adult dosage forms (e.g., splitting and crushing of tablets or opening of capsules) has been reported as a means to facilitate administration to children. To enhance swallowability and/or mask an unpleasant taste of the dosage form to be administered, crushed/split tablets or the contents of capsules are often mixed with food or drinks or suspended in a vehicle prior to administration. However, it seems that the risks and benefits of an approach whereby the dosage form is modified prior to administration in this manner are everything but clear. The aim of the present study was to gain an overview of the physicochemical properties of a number of fluids, soft foods and suspension vehicles that are commonly reported to be mixed with oral medications before administration to children to improve patient acceptability. For this purpose, physicochemical parameters of 15 different fluids, soft foods and suspension vehicles were measured. These included pH, buffer capacity, osmolality, surface tension and viscosity. Results of the study clearly show the differences in physicochemical properties of the test candidates. It is thus obvious that the type of fluid/food mixed with a drug product before administration may have a significant impact on bioavailability of the drug administered. Therefore, a risk-based assessment of such practices considering API properties, formulation features and physicochemical properties of the fluids and foods intended to be co-administered with the dosage form, in conjunction with the anatomical and physiological maturity of the gastro-intestinal tract in the intended paediatric population, should be an essential part of paediatric oral formulation development.

Correction: Peculiarities of the magneto-optical response in dispersions of anisometric pigment nano-particles

Correction for ‘Peculiarities of the magneto-optical response in dispersions of anisometric pigment nano-particles’ by A. Eremin et al., RSC Adv., 2016, 6, 80666–80669.

223 GENERATION OF INTERSPECIES CHIMERAS BETWEEN PRIMATE INDUCED PLURIPOTENT STEM CELLS AND PORCINE PARTHENOGENETIC EMBRYOS

The availability of human induced pluripotent stem cell (hiPSC) paves the way to generate regenerative tissue or organs from patient’s own stem cells. The production of chimeric piglets carrying organs that are entirely derived from human stem cells, or at least have a high contribution of human cells or tissues, could be used as a new tissue or an organ replacement in the future treatment of the patients. Here, we produced porcine-nonhuman primate chimeric embryos to assess the feasibility of the potential use of human iPSC for production of human stem cell-derived organs in pigs. Because in vitro culture conditions for cynomolgus monkey iPSC and porcine blastocysts are different, we first identified an effective in vitro culture system for porcine blastocysts and monkey iPSC. We compared blastocyst rates (Days 7 and 8) and number of cells of porcine parthenogenetic blastocysts (Day 8) cultured in 8 different monkey iPSC media and in porcine zygote medium 3 (PZM-3). The best developmental rates of porcine blastocysts were achieved in Knockout DMEM+20% serum replacement monkey medium (iPS 20% medium; N = 65, n = 3). The number of blastocysts on Day 8 cultured in iPS 20% medium was significantly higher (91%; P < 0.05) than in the commonly used porcine PZM-3 medium (65%). We found significantly fewer (P < 0.05) degenerate porcine embryos on Day 8 after culture in iPS 20% medium (9%) compared to PZM-3 (35%). The number of nuclei per blastocyst in iPS 20% medium (88 nuclei; N = 30, n = 3) was significantly higher (P < 0.0001) than in the PZM-3 medium (57 nuclei; N = 54, n = 3). Therefore, we decided to use iPS 20% medium for culture of porcine blastocysts injected with monkey iPSC. Thereafter, we injected clusters of 10 to 15 monkey iPSC transgenic with AAVS1-CAG-Venus into porcine parthenogenetic embryos from Days 4 and 6. Interspecies chimeras were cultured in iPS 20% medium for 24 (for Day 6 embryos) or 48 h (for Day 4 embryos) and observed by confocal microscopy to determine the proportion of Venus-expressing monkey iPSC in porcine embryos. Approximately 37% of blastocysts contained Venus-positive cells after injection of Day 6 embryos (N = 133, n = 4). In contrast, injection into porcine embryos from Day 4 resulted in 73% of Venus-positive blastocysts (N = 69, n = 3). Finally, we investigated proliferation and survival of monkey iPSC in interspecies chimeras after blastocyst plating onto murine fibroblasts. Chimeric blastocyst outgrowth resulted in Venus-expressing monkey iPSC proliferating over 1 week in culture. Outgrowths of all chimeric blastocysts established distinct but separate monkey and porcine stem cell colonies. Here, we optimized the culture conditions for an in vitro interspecies chimera assay in which monkey iPSC are able to survive in porcine embryos. Integration of monkey iPSC to host inner cell mass is relevant for the further contribution to the embryo development. Therefore, to verify this, analysis of cell-cell connection between monkey iPSC and porcine blastocysts and experiments using vivo-derived embryos are currently underway.

Peculiarities of the magneto-optical response in dispersions of anisometric pigment nano-particles

We demonstrate an unusually strong magneto-optical response of elongated plate-shaped pigment particles in magnetic fields ranging from 0 to 25 T.

PCA-based groupwise image registration for quantitative MRI

Quantitative magnetic resonance imaging (qMRI) is a technique for estimating quantitative tissue properties, such as the T1 and T2 relaxation times, apparent diffusion coefficient (ADC), and various perfusion measures. This estimation is achieved by acquiring multiple images with different acquisition parameters (or at multiple time points after injection of a contrast agent) and by fitting a qMRI signal model to the image intensities. Image registration is often necessary to compensate for misalignments due to subject motion and/or geometric distortions caused by the acquisition. However, large differences in image appearance make accurate image registration challenging. In this work, we propose a groupwise image registration method for compensating misalignment in qMRI. The groupwise formulation of the method eliminates the requirement of choosing a reference image, thus avoiding a registration bias. The method minimizes a cost function that is based on principal component analysis (PCA), exploiting the fact that intensity changes in qMRI can be described by a low-dimensional signal model, but not requiring knowledge on the specific acquisition model. The method was evaluated on 4D CT data of the lungs, and both real and synthetic images of five different qMRI applications: T1 mapping in a porcine heart, combined T1 and T2 mapping in carotid arteries, ADC mapping in the abdomen, diffusion tensor mapping in the brain, and dynamic contrast-enhanced mapping in the abdomen. Each application is based on a different acquisition model. The method is compared to a mutual information-based pairwise registration method and four other state-of-the-art groupwise registration methods. Registration accuracy is evaluated in terms of the precision of the estimated qMRI parameters, overlap of segmented structures, distance between corresponding landmarks, and smoothness of the deformation. In all qMRI applications the proposed method performed better than or equally well as competing methods, while avoiding the need to choose a reference image. It is also shown that the results of the conventional pairwise approach do depend on the choice of this reference image. We therefore conclude that our groupwise registration method with a similarity measure based on PCA is the preferred technique for compensating misalignments in qMRI.

Circulating Elastin Fragments Are Not Affected by Hepatic, Renal and Hemodynamic Changes, But Reflect Survival in Cirrhosis with TIPS

BACKGROUND AND AIMS

Progressive fibrosis increases hepatic resistance and causes portal hypertension with complications. During progressive fibrosis remodeling and deposition of collagens and elastin occur. Elastin remodeling is crucially involved in fibrosis progression in animal models and human data. This study investigated the association of circulating elastin with the clinical outcome in cirrhotic patients with severe portal hypertension receiving transjugular intrahepatic porto-systemic shunt (TIPS).

METHODS

We analyzed portal and hepatic venous samples of 110 cirrhotic patients obtained at TIPS insertion and 2 weeks later. The circulating levels of elastin fragments (ELM) were determined using specific monoclonal ELISA. The relationship of ELM with clinical short-time follow-up and long-term outcome was investigated.

RESULTS

Circulating levels of ELM showed a gradient across the liver before TIPS with higher levels in the hepatic vein. Interestingly, the circulating ELM levels remained unchanged after TIPS. The circulating levels of ELM in portal and hepatic veins correlated with platelet counts and inversely with serum sodium. Hepatic venous levels of ELM were higher in CHILD C compared to CHILD A and B and were associated with the presence of ascites. Patients with high levels of ELM in the hepatic veins before TIPS showed poorer survival. In multivariate analysis ELM levels in the hepatic veins and MELD were independent predictors of mortality in these patients.

CONCLUSION

This study demonstrated that circulating levels of ELM are not associated with hemodynamic changes, but might reflect fibrosis remodeling and predict survival in patients with severe portal hypertension receiving TIPS independently of MELD.

Resistência do couro de tilápia do Nilo submetido a diferentes processos de curtimento

O objetivo foi determinar a resistência de couros de tilápia do Nilo que foram submetidas a dois tipos de curtimento, estático e em movimento, com e sem a extração da hipoderme. As unidades empregadas na experiência foram dois baldes (estático) e um fulão (movimento). Foram avaliados os parâmetros de resistência ao rasgamento progressivo, tração e alongamento, para os tratamentos: Balde com carne região dorsal, Balde com carne região ventral, Balde sem carne região dorsal, Balde sem carne região ventral, Fulão com carne região dorsal, Fulão com carne região ventral, Fulão sem carne região dorsal e Fulão sem carne região ventral. O curtimento em fulão diferiu (p

Similar in vitro drug release as a surrogate of therapeutic equivalence of locally acting gastrointestinal products--what is the right in vitro method?

There is--apart from clinical trials--an ongoing discussion on how to demonstrate therapeutic equivalence for locally applied and locally acting products in the gastrointestinal tract. Possibly, among other alternatives, in vitro drug release models could be considered surrogates of drug release and availability at the site of action. However, to date the conditions in which in vitro models provide valid surrogates of in vivo release and availability at the site of action would have to be defined. To demonstrate the potential applicability of in vitro test methods for screening therapeutic equivalence of locally applied and locally acting gastrointestinal products and also to get an idea of which would be the right dosage form for an individual patient a series of in vitro studies was performed comparing a variety of in vitro release methods ranging from pharmacopoeial methods to "patient-specific" release methods in examining drug release of four mesalazine tablet formulations intended for local drug delivery in the gastrointestinal tract. Results from this study indicated that pharmacopoeial quality control methods are hardly applicable to predict the therapeutic equivalence of such products. Moreover, comparison of the results obtained with the different in vitro methods reveal that a prediction of the therapeutic equivalence for locally acting products in the gastrointestinal tract is unlikely based on release profiles obtained in a single drug release experiment. However, results from the study also indicated that a set of individualized biorelevant in vitro test scenarios might be very useful for both demonstrating therapeutic equivalence and selecting the appropriate drug product for a particular patient.

Near-isothermal furnace for in situ and real time X-ray radiography solidification experiments

In this paper, we present a newly developed near-isothermal X-ray transparent furnace for in situ imaging of solidification processes in thin metallic samples. We show that the furnace is ideally suited to study equiaxed microstructure evolution and grain interaction. To observe the growth dynamics of equiaxed dendritic structures, a minimal temperature gradient across the sample is required. A uniform thermal profile inside a circular sample is achieved by positioning the sample in the center of a cylindrical furnace body surrounded by a circular heater arrangement. Performance tests with the hypo-eutectic Al-15wt.%Cu and the near-eutectic Al-33wt.%Cu alloys validate the near-isothermal character of the sample environment. Controlled cooling rates of less than 0.5 K min(-1) up to 10 K min(-1) can be achieved in a temperature range of 720 K-1220 K. Integrated in our rotatable laboratory X-ray facility, X-RISE, the furnace provides a large field of view of 10.5 mm in diameter and a high spatial resolution of ∼4 μm. With the here presented furnace, equiaxed dendrite growth models can be rigorously tested against experiments on metal alloys by, e.g., enabling dendrite growth velocities to be determined as a function of undercooling or solutal fields in front of the growing dendrite to be measured.

Níveis de proteína bruta em dietas para pacu (Piaractus mesopotamicus) com 150 a 400g cultivados em tanques-rede

Um factor limitante na produção de organismos aquáticos refere à formulação de dietas de baixo custo com fontes de proteínas que satisfaçam as necessidades nutricionais dos animais. Portanto, este estudo teve como objetivo avaliar o desempenho e o crescimento do pacu (Piaractus mesopotamicus) cultivado em tanques-rede no reservatório de Itaipu. O peso médio inicial dos peixes foi de 150,5 ± 2,1g os quais foram distribuídos aleatoriamente em 20 tanques-rede (100 peixes/tanque) alimentados com cinco níveis de proteína bruta (PB) (18,5; 20,7; 23,7; 25,6 e 28,3 %), três vezes ao dia até a saciedade aparente. Avaliou-se o crescimento, composição muscular e perfil hematológico. Observou-se feito quadrático (p0,05). A derivação das equações indicaram que o percentual exigido de PB na dieta para juvenis de pacu foi de 25,8 %. Portanto, recomenda-se que as dietas para esta espécie, nestas condições de cultivo, devem ser formuladas com aproximadamente 26 % de PB para assegurar melhores condições de desempenho e crescimento.

The logarithmic contributions to the [Formula: see text] asymptotic massive Wilson coefficients and operator matrix elements in deeply inelastic scattering

We calculate the logarithmic contributions to the massive Wilson coefficients for deep-inelastic scattering in the asymptotic region [Formula: see text] to 3-loop order in the fixed flavor number scheme and present the corresponding expressions for the massive operator matrix elements needed in the variable flavor number scheme. Explicit expressions are given in Mellin [Formula: see text]-space.

Metabolically healthy and unhealthy obese--the 2013 Stock Conference report

Obesity is closely associated with cardiovascular diseases and type 2 diabetes, but some obese individuals, despite having excessive body fat, exhibit metabolic health that is comparable with that of lean individuals. The 'healthy obese' phenotype was described in the 1980s, but major advancements in its characterization were only made in the past five years. During this time, several new mechanisms that may be involved in health preservation in obesity were proposed through the use of transgenic animal models, use of sophisticated imaging techniques and in vivo measurements of insulin sensitivity. However, the main obstacle in advancing our understanding of the metabolically healthy obese phenotype and its related long-term health risks is the lack of a standardized definition. Here, we summarize the proceedings of the 13th Stock Conference of the International Association of the Study of Obesity. We describe the current research and highlight the unanswered questions and gaps in the field. Better understanding of metabolic health in obesity will assist in therapeutic decision-making and help identify therapeutic targets to improve metabolic health in obesity.

In vivo MRI mapping of iron oxide-labeled stem cells transplanted in the heart

In various stem cell therapy approaches poor cell survival has been recognized as an important factor limiting therapeutic efficacy. Therefore noninvasive monitoring of cell fate is warranted for developing clinically effective stem cell therapy. In this study we investigated the use of voxel-based R₂ mapping as a tool to monitor the fate of iron oxide-labeled cells in the myocardium. Mesenchymal stem cells were transduced with the luciferase gene, labeled with ferumoxide particles and injected in the myocardium of healthy rats. Cell fate was monitored over a period of 8 weeks by bioluminescence and quantitative magnetic resonance imaging. Bioluminescence signal increased during the first week followed by a steep decrease to undetectable levels during the second week. MR imaging showed a sharp increase in R₂ values shortly after injection at the injection site, followed by a very gradual decrease of R₂ over a period of 8 weeks. No difference in the appearances on R₂-weighted images was observed between living and dead cells over the entire time period studied. No significant correlation between the bioluminescence optical data and R₂ values was observed and quantitative R₂ mapping appeared not suitable for the in vivo assessment of stem cell. These results do not follow previous in vitro reports where it was proposed that living cells may be distinguished from dead cells on the basis of the R₂ relaxivities (intracellular and extracellular iron oxides). Cell proliferation, cell migration, cell death, extracellular superparamagnetic iron oxide dispersion and aggregation exhibit different relaxivities. In vivo these processes happen simultaneously, making quantification very complex, if not impossible.

Fósforo na alimentação de pacus criados em tanques-rede

Avaliaram-se o desempenho zootécnico, as características da carcaça, as características hematológicas e bioquímicas, a composição química e também a qualidade da água na criação de pacus Piaractus mesopotamicus em tanques-rede em reservatório e alimentados com dietas que continham diferentes quantidades de fósforo total. Foram utilizados 3.000 peixes, distribuídos em um delineamento inteiramente ao acaso, com cinco tratamentos e quatro repetições em 20 tanques-rede, sendo a unidade experimental composta por um tanque com 150 peixes. Os tratamentos foram constituídos por cinco dietas, elaboradas de modo a conterem quantidades de fósforo total de 6,0; 7,5; 9,0; 10,5 e 12,0g/kg por meio da suplementação de fosfato bicálcico. A quantidade de 6,0 a 12,0g/kg de fósforo total na ração pode ser utilizada na alimentação de pacus criados em tanques-rede, sem que haja comprometimento do desempenho dos animais, e pode-se recomendar, comercialmente, 6,0g/kg de fósforo total em dietas para pacus.