IODINE CONCENTRATION IN MILK OF SHEEP AND GOATS FROM FARMS IN SOUTH BOHEMIA

Iodine concentration was determined in milk samples collected from 60 sheep on 10 farms and from 94 goats of 64 farmers. The animals were grazed in the summer and fed hay of local harvests in the winter. Pregnant and lactating sheep received daily 0.2 to 0.4 kg of cereal meal. The iodine concentration in the hay fed to the sheep and goats ranged from 20.5 to 162.4 µg per 1 kg dry matter. The mean iodine concentration in sheep milk was 105.5 µg . l -1 . The corresponding value for the farms (n = 4) where the sheep had access to mineral licks (35 mg iodine per 1 kg) was 243.3 ± ± 87.2 µg . l -1 (ranged from 107.7 to 436.6) and for the rest of the farms (n = 6) 47.9 ± 27.8 µg . l -1 . Mean iodine concentrations in goat milk (31.6 µg . l -1 in 1998 and 63.0 µg . l -1 in 1999) were indicative of iodine deficiency. The corresponding value for the goats (n = 17) receiving iodised salt was 142.1 ± 102.6 µg . l -1 (ranged from 51.8 to 393.6) and for the remaining goats 19.3 ± ± 13.2 µg . l -1 . The mean iodine concentrations in goat milk on three farms on which neonatal goitre in kids was diagnosed ranged from 8.5 to 23.3 µg . l -1

Leaching refuse after sphalerite mineral for extraction zinc and cobalt

The paper deals with a possibility of zinc and cobalt extraction from refuse after sphalerite mineral leaching. It contains theoretic analysis of hydrometallurgical processes. Practical part describes samples and their leaching in 10 % and 20 % sulphuric acid. In the end of the paper it is evaluated under which conditions the highest yield of zinc and cobalt from refuse after sulphide ore leaching is reached

Non-alloyed Ni3Al based alloys – preparation and evaluation of mechanical properties

The paper reports on the fabrication and mechanical properties of Ni3Al based alloy, which represents the most frequently used basic composition of nickel based intermetallic alloys for high temperature applications. The structure of the alloy was controlled through directional solidification. The samples had a multi-phase microstructure. The directionally solidified specimens were subjected to tensile tests with concurrent measurement of acoustic emission (AE). The specimens exhibited considerable room temperature ductility before fracture. During tensile testing an intensive AE was observed

Content of Iodine in Broiler Meat

The present study brings current information on providing broilers with the required iodine level by the determination of its content in breast and leg muscles and on the relationship between those concentrations and iodine intake by the human population. The iodine content was assessed by the Sandell-Kolthoff method in 84 samples of broiler breast and leg muscles from seven farms in four districts of the Czech Republic, collected during the period from August to September 2004. Average iodine content in broiler breast and leg muscles was 18.9 ± 6.71 μg I kg-1 and 38.1 ± 19.79 μg I kg-1, respectively, and coefficient of variation was 35.5% and 52.0%, respectively. Iodine concentration in leg muscles was statistically significantly higher (P -1 and 18.3 to 61.2 μg I kg-1 in breast and leg muscles, respectively. The detected variations might have been caused by different iodine saturation of broilers from different herds, manifestation of physiological ability of respective animals to utilize the iodine source, potential effect of goitrogens and environmental conditions. Statistical significance of correlation (P -1 and 38.1 μg kg-1 in breast and leg muscles, respectively, the annual iodine intake is 452 to 911 μg; that represents 0.8 to 1.7% of the requirement per year, which is 150 μg day-1 for an adult person

Endocrine Disrupting Contaminants—Beyond the Dogma

Descriptions of endocrine disruption have largely been associated with wildlife and driven by observations documenting estrogenic, androgenic, antiandrogenic, and antithyroid actions. These actions, in response to exposure to ecologically relevant concentrations of various environmental contaminants, have now been established in numerous vertebrate species. However, many potential mechanisms and endocrine actions have not been studied. For example, the DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] metabolite, p,p′-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] is known to disrupt prostaglandin synthesis in the uterus of birds, providing part of the explanation for DDT-induced egg shell thinning. Few studies have examined prostaglandin synthesis as a target for endocrine disruption, yet these hormones are active in reproduction, immune responses, and cardiovascular physiology. Future studies must broaden the basic science approach to endocrine disruption, thereby expanding the mechanisms and endocrine end points examined. This goal should be accomplished even if the primary influence and funding continue to emphasize a narrower approach based on regulatory needs. Without this broader approach, research into endocrine disruption will become dominated by a narrow dogma, focusing on a few end points and mechanisms

Epidermal Growth Factor–PEG Functionalized PAMAM-Pentaethylenehexamine Dendron for Targeted Gene Delivery Produced by Click Chemistry

Aim of this study was the site-specific conjugation of an epidermal growth factor (EGF)-polyethylene glycol (PEG) chain by click chemistry onto a poly(amido amine) (PAMAM) dendron, as a key step toward defined multifunctional carriers for targeted gene delivery. For this purpose, at first propargyl amine cored PAMAM dendrons with ester ends were synthesized. The chain terminal ester groups were then modified by oligoamines with different secondary amino densities. The oligoamine-modified PAMAM dendrons were well biocompatible, as demonstrated in cytotoxicity assays. Among the different oligoamine-modified dendrons, PAMAM-pentaethylenehexamine (PEHA) dendron polyplexes displayed the best gene transfer ability. Conjugation of PAMAM-PEHA dendron with PEG spacer was conducted via click reaction, which was performed before amidation with PEHA. The resultant PEG-PAMAM-PEHA copolymer was then coupled with EGF ligand. pDNA transfections in HuH-7 hepatocellular carcinoma cells showed a 10-fold higher efficiency with the polyplexes containing conjugated EGF as compared to the ligand-free ones, demonstrating the concept of ligand targeting. Overall gene transfer efficiencies, however, were moderate, suggesting that additional measures for overcoming subsequent intracellular bottlenecks in delivery have to be taken

Solid-phase-assisted synthesis of targeting peptide-PEG-oligo(ethane amino)amides for receptor-mediated gene delivery.

In the forthcoming era of cancer gene therapy, efforts will be devoted to the development of new efficient and non-toxic gene delivery vectors. In this regard, the use of Fmoc/Boc-protected oligo(ethane amino)acids as building blocks for solid-phase-supported assembly represents a novel promising approach towards fully controlled syntheses of effective gene vectors. Here we report on the synthesis of defined polymers containing the following: (i) a plasmid DNA (pDNA) binding domain of eight succinoyl-tetraethylenpentamine (Stp) units and two terminal cysteine residues; (ii) a central polyethylene glycol (PEG) chain (with twenty-four oxyethylene units) for shielding; and (iii) specific peptides for targeting towards cancer cells. Peptides B6 and c(RGDfK), which bind transferrin receptor and αvβ3 integrin, respectively, were chosen because of the high expression of these receptors in many tumoral cells. This study shows the feasibility of designing these kinds of fully controlled vectors and their success for targeted pDNA-based gene transfer

Tree method for quantum vortex dynamics

We present a numerical method to compute the evolution of vortex filaments in superfluid helium. The method is based on a tree algorithm which considerably speeds up the calculation of Biot-Savart integrals. We show that the computational cost scales as Nlog{(N) rather than N squared, where $N$ is the number of discretization points. We test the method and its properties for a variety of vortex configurations, ranging from simple vortex rings to a counterflow vortex tangle, and compare results against the Local Induction Approximation and the exact Biot-Savart law.Comment: 12 pages, 10 figure

The sensitivity of the vortex filament method to different reconnection models

We present a detailed analysis on the effect of using different algorithms to model the reconnection of vortices in quantum turbulence, using the thin-filament approach. We examine differences between four main algorithms for the case of turbulence driven by a counterflow. In calculating the velocity field we use both the local induction approximation (LIA) and the full Biot-Savart integral. We show that results of Biot-Savart simulations are not sensitive to the particular reconnection method used, but LIA results are.Comment: 9 pages, 9 figure