Iodine in early pregnancy--is there enough?

Aims: To evaluate the iodine status of patients in early pregnancy and its dependence on level of thyroid-stimulating hormone (TSH). Methods: Between June 2005 and December 2006, 168 patients with a confirmed vital pregnancy (up to 10(th) week of pregnancy) were included in the study. The entry criteria were no prior thyroid disease, did not take any other medication, had not undergone radio-iodine therapy and did not take multivitamins containing iodine. The iodine status was measured as the amount of iodine in urine over 24 hours. The TSH level was determined from the blood using chemiluminescence. Results: The average ioduria value in patients was found to be 3.04 micromol/24 hr, with the norm 0.6-2.4 micromol/ 24 hr, median 2.9, SD 1.5. None of the patients had a value lower than 0.9 micromol/24 hr. The average TSH value was 1.98 mIU/l, median was 1.31, SD 0.98. The laboratory limits were set to 0.25-3 mIU/l for pregnant women in the first trimester. Three pregnancies ended in miscarriage by week 12, 1 miscarriage occurred in week 22 and the other pregnancies concluded in delivery between weeks 38-41. Fourteen patients had TSH levels above 3 mIU/l with normal levels od free thyroxine (T4) : 10.3-25 pmol/l. Conclusions: The results of this study did not reveal any iodine deficit in any of the patients. However 14 patients had elevated TSH levels signalling subclinical or incipiently clinical hypothyroidism. These pacients underwent levothyroxine therapy after endocrinologist's consultations.     

Mixed and non-cognate SNARE complexes. Characterization of assembly and biophysical properties.

Assembly of soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) proteins between two opposing membranes is thought to be the key event that initiates membrane fusion. Many new SNARE proteins have recently been localized to distinct intracellular compartments, supporting the view that sets of specific SNAREs are specialized for distinct trafficking steps. We have now investigated whether other SNAREs can form complexes with components of the synaptic SNARE complex including synaptobrevin/VAMP 2, SNAP-25, and syntaxin 1. When the Q-SNAREs syntaxin 2, 3, and 4, and the R-SNARE endobrevin/VAMP 8 were used in various combinations, heat-resistant complexes were formed. Limited proteolysis revealed that these complexes contained a protease-resistant core similar to that of the synaptic complex. All complexes were disassembled by the ATPase N-ethylmaleimide-sensitive fusion protein and its cofactor alpha-SNAP. Circular dichroism spectroscopy showed that major conformational changes occur during assembly, which are associated with induction of structure from unstructured monomers. Furthermore, no preference for synaptobrevin was observed during the assembly of the synaptic complex when endobrevin/VAMP 8 was present in equal concentrations. We conclude that cognate and non-cognate SNARE complexes are very similar with respect to biophysical properties, assembly, and disassembly, suggesting that specificity of membrane fusion in intracellular membrane traffic is not due to intrinsic specificity of SNARE pairing.     

Genome-wide mapping of Quantitative Trait Loci for fatness,fat cell characteristics and fat metabolism in three porcine F2 crosses

Background

QTL affecting fat deposition related performance traits have been considered in several studies and mapped on numerous porcine chromosomes. However, activity of specific enzymes, protein content and cell structure in fat tissue probably depend on a smaller number of genes than traits related to fat content in carcass. Thus, in this work traits related to metabolic and cytological features of back fat tissue and fat related performance traits were investigated in a genome-wide QTL analysis. QTL similarities and differences were examined between three F₂ crosses, and between male and female animals.

Methods

A total of 966 F₂ animals originating from crosses between Meishan (M), Pietrain (P) and European wild boar (W) were analysed for traits related to fat performance (11), enzymatic activity (9) and number and volume of fat cells (20). Per cross, 216 (M × P), 169 (W × P) and 195 (W × M) genome-wide distributed marker loci were genotyped. QTL mapping was performed separately for each cross in steps of 1 cM and steps were reduced when the distance between loci was shorter. The additive and dominant components of QTL positions were detected stepwise by using a multiple position model.

Results

A total of 147 genome-wide significant QTL (76 at P < 0.05 and 71 at P < 0.01) were detected for the three crosses. Most of the QTL were identified on SSC1 (between 76-78 and 87-90 cM), SSC7 (predominantly in the MHC region) and SSCX (in the vicinity of the gene CAPN6). Additional genome-wide significant QTL were found on SSC8, 12, 13, 14, 16, and 18. In many cases, the QTL are mainly additive and differ between F₂ crosses. Many of the QTL profiles possess multiple peaks especially in regions with a high marker density. Sex specific analyses, performed for example on SSC6, SSC7 and SSCX, show that for some traits the positions differ between male and female animals. For the selected traits, the additive and dominant components that were analysed for QTL positions on different chromosomes, explain in combination up to 23% of the total trait variance.

Conclusions

Our results reveal specific and partly new QTL positions across genetically diverse pig crosses. For some of the traits associated with specific enzymes, protein content and cell structure in fat tissue, it is the first time that they are included in a QTL analysis. They provide large-scale information to analyse causative genes and useful data for the pig industry.     

Interactions of trimeric purine nucleoside phosphorylases with ground state analogues--calorimetric and fluorimetric studies

Binding enthalpies, dissociation constants and stoichiometry of binding for interaction of trimeric calf spleen and Cellulomonas sp. purine nucleoside phosphorylases with their ground state analogues (substrates and inhibitors) were studied by calorimetric and spectrofluorimetric methods. Data for all ligands, with possible exception of hypoxanthine, are consistent with three identical non-interacting binding sites.     

Role of histamine receptors in the effects of histamine on the production of reactive oxygen species by whole blood phagocytes

Aims

The diverse physiological functions of histamine are mediated through distinct histamine receptors. In this study we investigated the role of H₂R and H₄R in the effects of histamine on the production of reactive oxygen species by phagocytes in whole blood.

Main methods

Changes in reactive oxygen species (ROS) production by whole blood phagocytes after treatment with histamine, H₄R agonists (4-methylhistamine, VUF8430), H₂R agonist (dimaprit) and their combinations with H₄R antagonist (JNJ10191584) and H₂R antagonist (ranitidine) were determined using the chemiluminescence (CL) assay. To exclude the direct scavenging effects of the studied compounds on the CL response, the antioxidant properties of all compounds were measured using several methods (TRAP, ORAC, and luminol–HRP–H₂O₂ based CL).

Key findings

Histamine, 4-methylhistamine, VUF8430 and dimaprit inhibited the spontaneous and OZP-activated whole blood CL in a dose-dependent manner. On the other hand, only VUF8430 was able to inhibit PMA-activated whole blood CL. Ranitidine, but not JNJ10191584, completely reduced the effects of histamine, 4-methylhistamine and dimaprit. The direct scavenging ability of tested compounds was negligible.

Significance

Our results demonstrate that the inhibitory effects of histamine on ROS production in whole blood phagocytes were caused by H₂R. Our results also suggest that H₄R agonists in concentrations higher than 10^− 6 M may also influence ROS production via binding to H₂R.     

Measurement of whole blood phagocyte chemiluminescence in the Wistar rat

The factors influencing the rat whole blood chemiluminescence (CL): concentrations of blood, luminol, zymosan or opsonized zymosan, volume of the reaction mixture, storage time of blood samples and the presence of anticoagulants were evaluated. The CL micromethod described provides a fast and sensitive tool for the determination of metabolic activity of phagocytes in the microlitre range of rat whole blood. © 1997 John Wiley & Sons, Ltd.