Modulation of iodide uptake by dialkyl phthalate plasticisers in FRTL-5 rat thyroid follicular cells

Plasticisers imparting flexibility to plastics are man-made chemicals abundantly present in the environment. Effects of six different dialkyl phthalates were studied in vitro in the rat thyroid cell line FRTL-5 on their ability to modulate basal iodide uptake mediated by the sodium/iodide symporter (NIS). The present study shows that diisodecyl phthalate (DIDP), dioctyl phthalate (DOP), diisononyl phthalate (DINP) and bis (2-ethylhexyl) phthalate (DEHP) significantly enhance iodide uptake when concentrations in the magnitude between 10(-4) M and 10(-3) M were applied. In this range, these phthalates do not assess toxicity on the cells. Specific inhibiton of NIS demonstrated that enhancement of iodide uptake is due to NIS. In contrast, benzyl butyl phthalate (BBP) also augments iodide uptake at 1mM but this concentration has just exceeded the toxicity threshold and dibutyl phthalate (DBP), the most toxic compound did not modulate iodide uptake at any concentration applied. As we can deduce from our results, plasticisers are capable of significantly modulating NIS mediated iodide uptake activity.

[Phytomedicine in dogs and cats: web-based survey among veterinarians in Austria, Germany and Switzerland]

In the last decades phytopharmaceuticals have stabilized their significance in human medicine. The aim of this study was to obtain information about the present situation of phytomedicine in three German-speaking countries. For that purpose questionnaires were sent via internet to 2675 veterinarians in Austria, Germany and Switzerland and the collected 189 answers were statistically evaluated. As shown in this paper, there is an increasing interest in veterinary phytotherapy. Presently three-quarters of the veterinarians are using phytoproducts in clinical practice. Herbal medicinal products are only seldom used in eye and ear infections as well as in endo- and ectoparasitoses but more often in diseases of the liver, joints, kidneys, heart and skin. Generally, phytodrugs are more frequently applied in chronic diseases as well as secondary medication, whereas the time of treatment usually exceeds one month. Basic advantages of medicinal phytoproducts have been shown to be the low side effects and the acceptance of the pet-owners and the only disadventage has been reported to be the lack of information. This study clearly shows the upward trend in using herbal drugs by veterinarians but the results also point to the lack of scientific knowledge about phytotherapeuticals in animal health.

Study of the effect of Bronchipret on the lung function of five Austrian saddle horses suffering recurrent airway obstruction (heaves)

The effects of an oral preparation containing an extract of thyme and primula (Bronchipret; Bionorica) on the lung function of five horses suffering heaves were determined in a longitudinal study. The horses accepted the product well. The plasma concentrations of the marker substance, thymol, indicated that at least one of the substances in the extract had been absorbed from the gastrointestinal tract. The compliance, pulmonary pressure and airway resistance of the horses' lungs were all significantly improved after one month of treatment However, the severity of their clinical signs and their arterial oxygen partial pressure had not improved significantly.

Pulmonary 15NO uptake in man

Nitric oxide (NO) is commonly thought to reveal more precise values of pulmonary gas uptake through alveolar-capillary membranes (DL) than the normally used carbon monoxide (CO). Since such measurements are influenced by a significant endogenous NO delivery within human airways, we propose the use of the naturally occurring (15)N-labelled stable nitric oxide isotope (15)NO. It occurs with a relative abundance of 0.37% of the dominating isotope (14)NO. Therefore, the endogenous (15)NO production can be neglected. In the present pilot study we demonstrate the workability of (15)NO in determining DL in healthy individuals. In seven female and 15 male volunteers, averaged values of DL increase with increasing mean alveolar volume as well as individual body height ( P=0.000001). Due to the very high significance level obtained from the multiple regression analysis, we conclude that the application of (15)NO establishes a novel approach to calculate standard values of DL. Such calculations can be employed to predict a reference for patients who suffer from pulmonary diffusion limitation.

Morphogenetic variability of faradiol monoesters in marigold Calendula officinalis L

The main compounds of lipophilic extracts of flower heads of marigold (Calendula officinalis L.) are triterpendiol esters, mainly faradiol laurate, faradiol myristate and faradiol palmitate. These faradiol-3-O-monoesters have been quantified for the first time by means of reversed phase HPLC with internal standardisation in different parts of C. officinalis plants, namely ray florets, disk florests, involucral bracts, receptacles, levaes and seeds. The amounts of the esters were highest in ray florets, approximately 10 times lower in disk florets than in the ray florets, and approximately 10 times lower in involucral bracts than in the disk florets. In the leaves only traces of the esters could be detected, and in the receptacles no esters could be detected at all. Quantification in the seed was not possible using this method because of interfering fatty compounds. Concerning the faradiol esters, the dried ray and disk florets only should be preferred as primary products for remedies as demanded in the recently published supplement of the Pharmacopoiea Europaea (1999). Breeding work should focus on varieties with a greater number of ray florets in order to improve the quality of herbal medicinal products derived from marigoid.

Determination of the presence of antioxidants deriving from sage and oregano extracts added to animal fat by means of assessment of the radical scavenging capacity by photochemiluminescence analysis

Herbs and their extracts with antioxidant capacity could be used directly as stabilisers of fat and indirectly as feed additives, in order to improve quality and shelf-life of meat and fat-containing food. In this work a sensitive analytical method is proposed for determination of the antioxidant activity measured by photochemiluminescence (PCL) in lard stabilised with extracts of sage (Salvia officinalis L.) or oreganum (Origanum vulgare L.). A prior step of purification of fat samples is required, in order to separate and concentrate the phenolics from lipidic substances. The method was validated by determination of recovery rate and repeatability. In addition fat samples originating from pigs fed with feed additives of Salviae folium or Origani herba were analysed to investigate the supposed antioxidative effects, that could increase the shelf-life of meat products. In contrast with lard mixed with extracts of sage or oregano, back fat samples originating from pigs fed with feed additives of the same herbs didn't show a higher antioxidant activity than the control group. On the one hand it seems possible to keep perishable fat-containing food longer by an addition of an extract of sage or oregano due to their antioxidative properties, on the other hand administration of feed additives of dried herbs to pigs had no effect on quality and shelf-life of fat obtained from these animals.

Medullary carcinoma of the thyroid gland

Medullary thyroid carcinoma (MTC) is an uncommon thyroid tumor that has attracted a great deal of interest because of its frequent presentation as a familial tumor and its primary involvement in the type II multiple endocrine neoplasia (MEN) syndromes MEN-IIA and MEN-IIB and familial medullary thyroid carcinoma (FMTC). The MTC tumor cells secrete the polypeptide hormone calcitonin, which serves as an excellent tumor marker, useful for defining the presence of disease, preoperatively or following thyroidectomy. The discovery that mutations in the RET proto-oncogene are associated with MEN-II syndromes was highly significant in that it demonstrated a clear correlation between genotype and phenotype; and most importantly it provided a mechanism whereby family members at risk could be identified by direct DNA analysis. Virtually all patients with MEN-IIA, MEN-IIB, and FMTC develop MTC; therefore there is a clear rationale for performing thyroidectomy as soon as a RET mutation has been identified. Because MTC appears to be much more aggressive in patients with MEN-IIB, thyroidectomy is performed during the first year of life in this setting, whereas in patients with MEN-IIA, where the tumor appears to be more indolent, the procedure can be safety delayed until age 5 years. Reoperative neck exploration in patients with evidence of persistent or recurrent MTC has been effective in a significant number of patients, although the success of the operation requires careful patient selection and preoperative assessment. MTC, as expressed in the MEN-II syndromes, is an excellent model to evaluate the usefulness of interventional therapy in patients demonstrated to have a genetic predisposition for cancer.

DNA and protein interactions of the small subunit of herpes simplex virus type 1 DNA polymerase

Herpes simplex virus DNA polymerase (HSV pol) holoenzyme consists of a large catalytic (UL30 gene product) and a small auxiliary subunit (UL42 gene product). The DNA binding of HSV pol, its cofactor, and the assembled holoenzyme complex was studied by bandshift analysis using purified proteins expressed via recombinant baculovirus. The functional activity of the recombinant UL42, purified by phenyl-Sepharose chromatography, was confirmed by its ability (1) to convert the salt sensitivity of both, 3'-5' exonuclease and polymerase, activities of HSV pol and (2) to enhance the processivity of polymerization. Bandshift analyses revealed that the HSV pol holoenzyme-DNA complex was stably formed up to a salt concentration of 50 mM ammonium sulfate, indicating that the restricted DNA and protein interactions of both HSV pol and UL42 are responsible for the observed salt preference of the HSV pol holoenzyme under standard assay conditions in vitro. Studies of the assembly of the holoenzyme complex demonstrated that initial DNA binding of HSV pol was advantageous for the formation of the HSV pol holoenzyme-DNA complex.

Binding of Ca2+ and Zn2+ to human nuclear S100A2 and mutant proteins

The Ca2+-binding protein S100A2 is an unusual member of the S100 family, characterized by its nuclear localization and down-regulated expression in tumorigenic cells. In this study, we investigated the properties of human recombinant S100A2 (wtS100A2) and of two mutants in which the amino-terminal Ca2+-binding site I (N mutant) and in addition the carboxyl-terminal site II (NC mutant) were replaced by the canonical loop (EF-site) of alpha-parvalbumin. Size exclusion chromatography and circular dichroism showed that, irrespective of the state of cation binding, wtS100A2 and mutants are dimers and rich in alpha-helical structure. Flow dialysis revealed that wtS100A2 binds four Ca2+ atoms per dimer with pronounced positive cooperativity. Both mutants also bind four Ca2+ atoms but with a higher affinity than wtS100A2 and with negative cooperativity. The binding of the first two Ca2+ ions to the N mutant occurred with 100-fold higher affinity than in wtS100A2 and a 2-fold increase for the last two Ca2+ ions. A further 2-3-fold increase of affinity was observed for respective binding steps of the NC mutant. The Hummel-Dryer method demonstrated that the wild type and mutants bind four Zn2+ atoms per dimer with similar affinity. Fluorescence and difference spectrophotometry showed that the binding of Ca2+ and Zn2+ induces considerable conformational changes, mostly attributable to changes in the microenvironment of Tyr76 located in site II. Fluorescence enhancement of 4,4'-dianilino-1, 1'-binaphthyl-5,5'-disulfonic acid clearly indicated that Ca2+ and Zn2+ binding induce a hydrophobic patch at the surface of wtS100A2, which, as in calmodulin, may be instrumental for the regulatory role of S100A2 in the nucleus.

Dehydroepiandrosterone sulfate does not prevent spontaneous and iodine-induced lymphocytic thyroiditis and diabetes mellitus in the BB/Wor rat

Chronic feeding of dehydroepiandrosterone (DHEA) and its sulfated metabolite, dehydroepiandrosterone sulfate (DHEAS), has previously been reported to decrease hyperglycemia, obesity, cancer, and autoantibody generation in a number of animal models and to increase muscle mass and physiological and psychological well-being in elderly humans, although these latter studies remain controversial. The present study was carried out to determine whether large amounts of DHEAS given orally would prevent the occurrence of spontaneous and iodine-induced autoimmune lymphocytic thyroiditis (LT) and/or spontaneous insulin-dependent diabetes mellitus (DM) in male and female BB/Wor rats. DHEAS was administered by gavage (44 mg/rat/day) or in the chow (133 mg/rat/day) to LT- and DM-prone rats from 30 to 120 days of life; some of these rats also received iodine in the drinking water to enhance the incidence and intensity of LT. Onset of DM requiring protamine zinc insulin and its maintenance dose were assessed. Rats were killed at 90 or 120 days of age and blood, thyroid, adrenals, pancreases, testes, and ovaries were removed. Serum glucose, DHEA, DHEAS, thyroxine (T4), tri-iodothyronine (T3) and thyrotropin (TSH) concentrations were measured in all rats in both experiments. Serum DHEAS concentrations were 10-fold higher in the rats given the steroid by gavage or in the diet compared with levels in control rats. DHEAS administered over a prolonged period of time had no significant effect on body weight, incidence and severity of DM, incidence and intensity of spontaneous and iodine-induced LT, and thyroid, pancreas and testes weights but did significantly decrease adrenal and ovarian weights. Serum T4, T3, and TSH concentrations were similar in control and DHEAS-treated rats. In conclusion, DHEAS did not prevent the occurrence of iodine-induced or spontaneous autoimmune LT or spontaneous DM in the BB/Wor rat, at variance with its reported immunosuppressive effects in other animal models.