Direct Compression Behavior of Low- and High-Methoxylated Pectins

The objective of this study was to evaluate possible usefulness of pectins for direct compression of tablets. The deformation behavior of pectin grades of different degree of methoxylation (DM), namely, 5%, 10%, 25%, 35%, 40%, 50%, and 60% were, examined in terms of yield pressures (YP) derived from Heckel profiles for both compression and decompression and measurements of elastic recovery after ejection. All pectin grades showed a high degree of elastic recovery. DM 60% exhibited most plastic deformation (YP 70.4 MPa) whereas DM 5% (104.6 MPa) and DM 10% (114.7 MPa) least. However, DM 60% gave no coherent tablets, whereas tablet tensile strengths for DM 5% and DM 10% were comparable to Starch 1500®. Also, Heckel profiles were similar to Starch 1500®. For sieved fractions (180–250 and 90–125 μm) of DM 25% and DM 40% originating from the very same batch, YPs were alike, indicating minor effects of particle size. These facts indicate that DM is important for the compaction behavior, and batch-to-batch variability should also be considered. Therefore, pectins of low degree of methoxylation may have a potential as direct compression excipients

Dietary iron intake in the first 4 months of infancy and the development of type 1 diabetes: a pilot study

<p>Abstract</p> <p>Aims</p> <p>To investigate the impact of iron intake on the development of type 1 diabetes (T1DM).</p> <p>Methods</p> <p>Case-control study with self-administered questionnaire among families of children with T1DM who were less than 10 years old at the time of the survey and developed diabetes between age 1 and 6 years. Data on the types of infant feeding in the first 4 months of life was collected from parents of children with T1DM (n = 128) and controls (n = 67) <10 years old. Because some cases had sibling controls, we used conditional logistic regression models to analyze the data in two ways. First we performed a case-control analysis of all 128 cases and 67 controls. Next, we performed a case-control analysis restricted to cases (n = 59) that had a sibling without diabetes (n = 59). Total iron intake was modeled as one standard deviation (SD) increase in iron intake. The SD for iron intake was 540 mg in the total sample and 539 mg in the restricted sample as defined above.</p> <p>Results</p> <p>The median (min, max) total iron intake in the first 4 months of life was 1159 (50, 2399) mg in T1DM cases and 466 (50, 1224) mg among controls (<it>P </it>< 0.001). For each one standard deviation increase in iron intake, the odds ratio (95% confidence interval) for type 1 diabetes was 2.01 (1.183, 3.41) among all participants (128 cases and 67 controls) while it was 2.26 (1.27, 4.03) in a restricted sample of T1 D cases with a control sibling (59 cases and 59 controls) in models adjusted for birth weight, age at the time of the survey, and birth order.</p> <p>Conclusion</p> <p>In this pilot study, high iron intake in the first 4 months of infancy is associated with T1DM. Whether iron intake is causal or a marker of another risk factor warrants further investigation.</p

Preparation of proton-conducting membranes by direct sulfonation. 1. Effect of radicals and radical decay on the sulfonation of poly(vinyl fluoride) films

The effect of irradiation treatment on the structure and sulfonation reactivity of polyvinyl fluoride (PVF) films was studied mainly with EPR and IR spectroscopy. The main radical species produced by electron irradiation are aliphatic radicals, whereas proton irradiation creates a significant amount of polyenyl radicals. The half-life time of the aliphatic radicals was about 6 h. FTIR study shows that sulfonation reaction of PVF is a single-stage process and thus the formed sulfonic acid structures do not react further and produce new structures. In addition, it is independent of the irradiation treatment. Despite the careful synthesis and removal of O 2 from the sulfonation solution, the most important side reaction produced by the sulfonation is the formation of C=O functionalities. Irradiation treatment increases the C=O content. Both the sulfonation time and sulfonation reagent concentration demonstrate similar linear correlation with the extent of oxidation. Therefore, the oxidation cannot be decreased by means of optimizing these variables. The only important factor allowing adjustment of the structure of the final membranes is the type of irradiation and radical decay in the case of proton irradiation. Irradiation with either electrons or protons did not increase the ion exchange capacity as measured with a titrimetric method. IR study of the samples showed, however, indication of the formation of derivates of sulfonic acid in the proton-irradiated samples containing radicals

Preparation of proton-conducting membranes by direct sulfonation. 1. Effect of radicals and radical decay on the sulfonation of poly(vinyl fluoride) films

The effect of irradiation treatment on the structure and sulfonation reactivity of polyvinyl fluoride (PVF) films was studied mainly with EPR and IR spectroscopy. The main radical species produced by electron irradiation are aliphatic radicals, whereas proton irradiation creates a significant amount of polyenyl radicals. The half-life time of the aliphatic radicals was about 6 h. FTIR study shows that sulfonation reaction of PVF is a single-stage process and thus the formed sulfonic acid structures do not react further and produce new structures. In addition, it is independent of the irradiation treatment. Despite the careful synthesis and removal of O 2 from the sulfonation solution, the most important side reaction produced by the sulfonation is the formation of C=O functionalities. Irradiation treatment increases the C=O content. Both the sulfonation time and sulfonation reagent concentration demonstrate similar linear correlation with the extent of oxidation. Therefore, the oxidation cannot be decreased by means of optimizing these variables. The only important factor allowing adjustment of the structure of the final membranes is the type of irradiation and radical decay in the case of proton irradiation. Irradiation with either electrons or protons did not increase the ion exchange capacity as measured with a titrimetric method. IR study of the samples showed, however, indication of the formation of derivates of sulfonic acid in the proton-irradiated samples containing radicals

Влияние конструкции порошкового ингалятора на отложение лекарственного вещества в дыхательных путях

Disodium chromoglycate particles were labelled with pure gamma-radiator, 99m Tc, using the co-precipitation technique based on spray drying. Radioactive drug particles were mixed, with lactose carrier and filled into hard gelatin capsules. Seven healthy volunteers inhaled drug doses using Spinhaler, I. S. F., Berotec, and Rotahaler dry powder devices. The fractional deposition of drug particles in the upper airways and lung region were monitored using a gamma camera. The fraction of the dose relained in the powder inhaler was the smallest for I. S. F. and especially for Berotec inhalers. These devices have narrower air channel constructions with a smaller wall surface area than the Spinhaler and Rotahaler devices. Thus the sticking of the drug particles onto the plastic walls was less probable for the first mentioned devices. The drug particles from all the dry powder inhalers seemed to be more able to follow the inspired air stream without depositing in the upper airways than previously documented for pressurized metered dose aerosols. I. S. F. and Berotec inhalers with narrow air channels gave the greatest lung deposition of the inhaled drug, particles. Thus the design of the dry powder inhaler was noticed to have a remark able effect both on the emptying of the capsules as well as on the redispersion of the powder mixture.