Horse owners' attitudes towards and motivators for using complementary and alternative veterinary medicine.

BACKGROUND: Complementary and alternative veterinary medicine (CAVM) is becoming increasingly popular in horses. METHODS: Online, cross-sectional survey in 1532 horse owners. Attitude towards CAVM, subjective norms, perceived behavioural control and intention for future CAVM use were measured based on the theory of planned behaviour. Structural equation modelling was performed to characterize factors influencing intention to use CAVM. RESULTS: Past use of CAVM, predominantly manual therapies and herbal supplements, was reported by 72.5% of all participants. Frequently reported indications were improving horse's well-being, illness which did not resolve after conventional treatment and chronic illness. The attitude towards CAVM was positive with a median (interquartile range) score of 6 of 7 (4.75-7.00). Predictors for past CAVM use were higher owner age, alternative medicine self-use and higher education (non-university). The strongest predictor of future CAVM usage was perceived behavioural control and perceived CAVM efficacy, as well as positive attitude towards and perceived knowledge about CAVM. The veterinarian was reported as a source of information about CAVM by 86.4% of all participants. CONCLUSIONS: Horse owners showed a high intention to use CAVM with the owners' perceived behavioural control and perceived CAVM efficacy as the strongest predictor. Veterinarian-client communication is important to inform horse owners correctly.

[First line endonasal dacryocystorhinostomy Technique and results. Comparison between diode laser and electrocautery instrument. Study based on 422 procedures]. / Dacryocystorhinostomie endonasale de première intention. Technique et résultats. Comparaison entre le laster diode et le bistouri électrique. Etude sur 422 interventions.

PURPOSE OF THE STUDY: To assess the results of the first procedures of endoscopic endonasal dacryocystorhinostomy (ENL DCR). To study the efficiency of diode laser in this operation versus electrocautery instruments (ECI). DESIGN: Prospective study; comparative study. METHODS: Intraoperative comparison between ECI and diode laser is based on 422 ENL DCR achieved between June 1997 until June 2000. Three hundreds and sixty three procedures were diode laser assisted and 59 procedures were done with the use of an ECI. The diode laser was only used to vaporize nasal mucosa laying on the osteotomy site, to realize partial turbinectomy and to vaporize polyps and synechiae. Intraoperative comparison was based on the followings: frequency and extent of bleeding, quality of visibility, perception of pain during the use of the instrument and duration of the operation. Postoperative comparison is based on 318 procedures. Comparison was based on: frequency of granuloma formation in the nasal mucosa at the site of the osteotomy, frequency of acquired nasal synechiae, frequency of important crusting reaction of the nasal mucosa; success rates after a minimum follow up of 6 months. RESULTS: Intraoperative haemorrhages were fewer and smaller in the diode laser assisted procedures than in ECI assisted procedures; visibility was better with the diode laser; the use of the diode laser was painless versus 24% of patients complaining of pain during the use of electro-cautery. The duration of the procedure was shorter with the diode laser (29'30 vs 37'). In the postoperative follow-up frequency of granuloma formation was equal with the two instruments, synechiae were fewer with the diode laser (11% vs 22%) just like crusting reaction of the nasal mucosa (7% vs 36%). Success rates were similar (diode laser: 91.94% vs EC: 86.66%). CONCLUSION: Because of the effeciency of the vaporization and coagulation, the diode laser, in comparison with the ECI, allows to shorten mean operative time, to improve the visibility and to decrase bleeding. Contrary to EC it's use is painless. Fewer important crusting reactions and fewer synechiae after diode laser assisted procedures tend to prove than postoperative inflammation and surgical trauma are smaller than with ECI. There is no statiscally signifant difference between the success rates of ENL laser diode assisted procedures and ENL ECI assisted procedures.

Cellular and biochemical mechanisms by which environmental oestrogens influence reproductive function.

The biology and physiology of the male as well as female reproductive system is hormonally regulated. Abnormalities in the dynamics of hormone production, metabolism and elimination, as well as their binding to certain target tissues, has been associated with pathophysiological conditions of the reproductive system. Although oestrogens are known to be one of the major hormone groups in regulating the reproductive function and the fertilization process, the cellular and biochemical mechanism or mechanism(s) via which oestrogens induce their effects are still not fully defined. Moreover, in a modern environment we are also exposed to a wide battery of environmental agents which are structurally similar to oestrogens, and termed 'environmental oestrogens'. Because environmental oestrogens have been shown to mimic some of the effects of oestradiol, it has been postulated that these exogenous chemicals may influence or interfere with the oestrogen-dependent reproductive processes, and may be associated with beneficial as well as deleterious effects on the reproductive system. In this regard, two classes of environmental oestrogens have been widely studied, i.e. phyto-oestrogens (plant-derived dietary oestrogens) and xeno-oestrogens (industrial chemicals, including polychlorinated biphenyls, DDT, TCDD, dioxins, etc.). The main focus of this review is to provide an overview on the cellular and biochemical mechanism(s) by which xeno-oestrogens and phyto-oestrogens influence the oestrogen-dependent reproductive functions and induce their deleterious or protective effects on the reproductive system.

Vascular effects of environmental oestrogens: implications for reproductive and vascular health.

Environmental oestrogens are defined as xenobiotics structurally resembling oestrogen, and are divided into two broad categories, xeno-oestrogens and phyto-oestrogens. Environmental oestrogens may contribute importantly to the increased incidence of reproductive disorders in the modern environment. Although the mechanisms by which environmental oestrogens induce their deleterious effects on the reproductive system remain poorly defined, it is likely that the vascular effects of these compounds play a critical role. In this regard, oestradiol strongly regulates both angiogenesis and vascular remodelling by influencing the growth and function of vascular endothelial cells (EC) and smooth muscle cells (SMC). Since blood vessels, by undergoing angiogenesis, vascular regression and vascular remodelling, actively participate in the normal functioning of reproductive organs, environmental oestrogens-by mimicking or antagonizing the vascular effects of oestradiol-may induce abnormalities in vascular function and structure leading to reproductive disorders such as pre-eclampsia, endometriosis, impaired follicular development, inefficient implantation, impotence and infertility. The purpose of the present review is to summarize the evidence regarding the vascular effects of xeno-oestrogens and phyto-oestrogens and to discuss the implications for these effects on the reproductive system.

Xeno-oestrogens and phyto-oestrogens induce the synthesis of leukaemia inhibitory factor by human and bovine oviduct cells.

In bovine oviduct cells 17beta-oestradiol can induce the synthesis of leukaemia inhibitory factor (LIF), a glycoprotein essential for embryo implantation. Therefore substances which are structurally similar to 17beta-oestradiol and possess oestrogenic activity may also modulate LIF synthesis and influence the reproductive process. We used primary cultures of bovine and human oviduct cells (epithelial cells:fibroblasts 1:1) to compare the effects of 17beta-oestradiol, phyto-oestrogens (genistein, biochanin A, daidzein, formononetin, and equol) and xeno-oestrogens [polychlorinated biphenyls (PCB): trichlorobiphenyl, 4-hydroxy-trichlorobiphenyl and 4-hydroxy-dichlorobiphenyl] on LIF synthesis. Immunoreactive LIF-enzyme-linked immunosorbent assay was used to determine the concentration of LIF in the culture medium. Similar to 17beta-oestradiol, genistein (0.02-2 micromol/l) induced LIF synthesis in bovine oviduct cells in a concentration-dependent manner. Equol, biochanin A and daidzein (2 micromol/l), 4-hydroxy-trichlorobiphenyl and 4-hydroxy-dichlorobiphenyl (0.01-10 micromol/l) but not formononetin (2 micromol/l) also induced LIF synthesis in bovine cells. Phyto-oestrogens and xeno-oestrogens also induced LIF synthesis in human oviduct cells (P < 0.05). The stimulatory effects of PCB, phyto-oestrogens and 17beta-oestradiol were blocked by ICI 182,780 (1 micromol/l). Moreover, 17beta-oestradiol, 4-hydroxy-trichlorobiphenyl, 4-hydroxy-dichlorobiphenyl, genistein, tamoxifen and ICI 182,780 displaced [(3)H]17beta-oestradiol from cytosolic oestrogen receptors in bovine oviduct cells. These results suggest that phyto-oestrogens and PCB mimic the effects of oestradiol in inducing LIF synthesis by bovine and human oviduct cells and that these stimulatory effects are oestrogen receptor-mediated. Environmental oestrogens act as endocrine modulators/disrupters and may induce deleterious effects on the reproductive process by influencing LIF synthesis in a non-cyclic fashion leading to tubal infertility.

Phytoestrogens inhibit growth and MAP kinase activity in human aortic smooth muscle cells.

-Estrogens are known to induce cardioprotective effects by inhibiting smooth muscle cell (SMC) growth and neointima formation. However, the use of estrogens as cardioprotective agents is limited by carcinogenic effects in women and feminizing effects in men. If noncarcinogenic and nonfeminizing estrogenlike compounds, such as natural phytoestrogens, afford cardioprotection, this would provide a safe method for prevention of cardiovascular disease in both men and women. Therefore, we evaluated and compared in human aortic SMCs the effects of phytoestrogens (formononetin, genistein, biochanin A, daidzein, and equol) on 2.5% fetal calf serum-induced proliferation (3H-thymidine incorporation and cell number), collagen synthesis (3H-proline incorporation), and total protein synthesis (3H-leucine incorporation) and on PDGF-BB (25 ng/mL)-induced migration (modified Boydens chambers). Moreover, the effects of phytoestrogens on PDGF-BB (25 ng/mL)-induced mitogen-activated protein kinase (MAP kinase) activity in SMCs was also studied. Phytoestrogens inhibited proliferation, collagen and total protein synthesis, migration, and MAP kinase activity in a concentration-dependent manner and in the following order of potency: biochanin A>genistein>equol>daidzein>formononetin. In conclusion, our studies provide the first evidence that in human aortic SMCs phytoestrogens inhibit mitogen-induced proliferation, migration and extracellular matrix synthesis and inhibit/downregulate MAP kinase activity. Thus, phytoestrogens may confer protective effects on the cardiovascular system by inhibiting vascular remodeling and neointima formation and may be clinically useful as a safer substitute for feminizing estrogens in preventing cardiovascular disease in both women and men.

[Hormone substitution in menopause]. / Hormonsubstitution in der Menopause.

Postmenopausal estrogen deprivation is a major cause for vasomotor and psychic complaints and for urogenital dysfunction, it is also a risk factor for osteoporosis, hip fracture, cardiovascular disease and possibly dementia. Hormone replacement therapy is highly effective in improving hot flushes, insomnia, depression and genital atrophia, but it prevents bone mineral loss and coronary heart disease as well. The potential risk for thromboembolism remains small and there is no final proof for a significant increase of breast cancer. Hysterectomized women may be treated with unopposed estrogens, otherwise progestogens must be added in a cyclic or continuous manner in order to protect the endometrium. Natural estrogens are to be preferred, they may be administered orally, percutaneously or vaginally. Long acting subcutaneous implants are also gaining interest. Prolonged treatment for many years is essential in order to be preventive. Compliance by motivation and comprehensive care is therefore indispensable.

Use of a continuous assay of oxygen consumption to evaluate the pharmacology of 5-lipoxygenase inhibitors.

A variety of assay systems have been utilized to evaluate the inhibition of the key enzyme in leukotriene (LT) biosynthesis, 5-lipoxygenase (5-LO). We have developed an assay utilizing a cytosolic preparation of 5-LO from rat basophilic leukemia (RBL-1) cells. Enzyme activity was monitored by continuous measurement of oxygen consumption. High performance liquid chromatography (HPLC) analysis of products showed exclusive generation of 5-LO products. The assay proved useful for the evaluation of a variety of chemical classes of lipoxygenase inhibitors and clearly differentiated those compounds which extended the lag phase (e.g. A-64077) as opposed to the propagation phase of the enzyme activity (e.g. SK & F 105561). The data generated were in reasonable agreement with results from the assay of isolated human monocyte 5-LO and, with the exception of compounds which appear to have a significant effect on 5-LO translocation (e.g. MK-886 and Wy-49 232), inhibition of LT production by intact monocytes. This assay system proved to be a convenient and informative method to analyze inhibition of 5-LO activity.

Granulocyte colony stimulating factor: animal studies for risk assessment.

In mice, rats, hamsters, dogs, and monkeys, doses of > or = 1.1 microgram/kg/day of r-metHuG-CSF stimulated neutrophil production in bone marrow. There was a resulting rapid release of mature neutrophils from the marrow storage pool into circulation and a distinct neutrophilia maintained for the dosing period in each study. R-metHuG-CSF corrected cyclic hemopoiesis in dogs, established sustained endogenous recovery after lethal bone marrow suppression, and elicited differention and maturation induction and enhanced functional activity of mature neutrophils. Reversible side effects due to an exaggerated pharmacological activity of the growth factor were observed at doses of > or = 115 micrograms/kg/day, with the exception of a rodent-specific osteopathy, which occurred in some animals after 3 months at > or = 5.7 micrograms/kg/day. The only irreversible adverse effect was seen in monkeys at doses of 1150 micrograms/kg/day (equivalent to 200 times the recommended human dose) when leukocyte counts exceeded 100 x 10(9)/liter. It consisted of hyperleukocytosis, leukostasis in terminal capillaries of the brain, followed by tissue hypoxia and intracerebral hemorrhage. Local tolerance of r-metHuG-CSF was good and no hypersensitivity reactions were observed. Antibody formation was minimal in monkeys but occasionally marked in dogs, which is not suprising due to the species difference in the amino acid sequence of the factor. The use of recombinant canine G-CSF, however, did not elicit formation of neutralizing antibodies in dogs. Moreover, relatively few untoward effects were seen in reproductive toxicology except when maternal toxicity or weight loss of dams occurred. In addition, negative results were obtained in all genotoxicity studies performed.

MR assessment of myelination in infants and children: usefulness of marker sites.

A retrospective study was made of 60 patients, 1 month to 3 years old, to determine the normal progression of white matter myelination on MR imaging. All examinations were performed with a 1.5-T unit, and axial T1- and T2-weighted images were evaluated in each patient. Multiple sites in the cerebral hemisphere and cerebellum were examined in each case for the presence and degree of myelination. The results show that MR imaging is sensitive to the early changes of white matter myelination, and imaging patterns correlate with known patterns from pathologic studies. At the time of birth in a full-term infant the posterior limb of the internal capsule, central corona radiata, and cerebellar peduncles show visible myelination. Myelination in the centrum semiovale then proceeds anteriorly and posteriorly. Both T1- and T2-weighted images show these changes, which are best explained by a decrease in the water content of white matter as myelination progresses. Knowledge of these normal myelination patterns is essential in evaluating MR imaging studies in infants and children and in diagnosing delayed myelination.

Pregnancy-specific and pregnancy-associated proteins in threatened abortion.

Pregnancy sera (390) were taken between the 5th and 16th weeks of gestation, from subjects whose pregnancies were uneventful throughout the entire gestation period. In-house curves of first-trimester normal values (10th, 50th, 90th percentile) were established for human chorionic gonadotropin (hCG), human placental lactogen (hPL), pregnancy-specific beta 1-glycoprotein (SP-1), pregnancy-associated plasma protein A (PAPP-A), and pregnancy-associated alpha 2-glycoprotein (alpha 2-PAG) after the measurement of these proteins in the sera by immunoassay. Eighty sera from patients with threatened abortion were also obtained and the placental proteins mentioned above were determined. Values falling below the 10th percentile of the normal population were classified as positive (i.e., pathological) results; the others were considered negative. Based on the outcome of the pregnancy, the results were grouped into true positives (low value and lost pregnancy), false positives (low value and ongoing pregnancy), true negatives, and false negatives. The sensitivity, specificity, and the positive predictive value of each protein as an indicator for abortion were calculated. In terms of specificity hCG and SP-1 were good, whilst PAPP-A and hCG showed the highest sensitivity. The best predictive values were obtained from SP-1 and hCG. The results show that PAPP-A and SP-1 perform satisfactorily but that none of these proteins significantly improves on hCG.

Biosynthesis of riboflavin. Incorporation of 13C-labeled precursors into the xylene ring.

Growing cultures of Ashbya gossypii were supplemented with various 13C-labeled precursors including [1-13C]acetate, [2-13C]acetate, [1-13C]ribose, [1-13C]glucose, [6-13C]glucose, and [2-13C]glycerol. Riboflavin was isolated from the culture medium, chemically converted to riboflavin tetraacetate, and analyzed by 13C NMR spectroscopy. The xylene ring of riboflavin is formed by dismutation of 6,7-dimethyl-8-ribityllumazine, thus the 8 carbon atoms of the riboflavin xylene ring are composed of 4 biochemically different carbon atoms which are duplicated in the dismutation. The formation of the lumazine from a pyrimidine precursor requires the addition of these 4 carbon atoms which constitute C-6 alpha, C-6, C-7, and C-7 alpha of the lumazine. Results from the present work indicate that these 4 carbon atoms do not arise from acetate, diacetyl, acetoin, or a tetrose, nor from loss of 1 or 2 carbon atoms from either end of a pentose or hexose. Additionally, the data do not support the recent contention that these 4 atoms arise via a dismutation of the pyrimidine precursor of the lumazine. The findings show that there exists a close correspondence between the lumazine carbons 6 alpha, 6, and 7 with C-1, C-2, and C-3, respectively, of a pentose, while C-7 alpha corresponds to C-5 rather than C-4 of a pentose. This in conjunction with results reported earlier indicates an intramolecular rearrangement involving carbons 3, 4, and 5 of a pentose or its biochemical equivalent.

d,1-alpha-Tocopheryl acetate (vitamin E): a long term toxicity and carcinogenicity study in rats.

Rats were fed vitamin E at various dietary concentrations providing dosages of up to 2000 mg/kg bodyweight/day for 104 weeks. Vitamin K supplementation suppressed the induced hypoprothrombinaemia. Growth rate and survival were unaltered by treatment, and, apart from a trend towards fewer mammary tumours in females, the tumour profile was unaffected. Changes in serum liver enzyme activity and in the appearance of the hepatic macrophages suggested a limited hepatic response to vitamin E overload.

Stimulation of tubero-infundibular dopamine neurones and gonadotrophin secretion.

1. In ovariectomized rats pre-treated with oestrogen and progesterone, the intensity of the catecholamine fluorescence was determined by micro-fluorimetry in the cell bodies of the tubero-infundibular dopamine neurones (situated in the arcuate and periventricular hypothalamic nuclei). The concentrations of follicle-stimulating (FSH) and luteinizing hormone (LH) in serum and pituitary were estimated by bio-assay.2. The characteristic changes in fluorescence intensity of the tuberal catecholamine-containing nerve cell group that are induced by unilateral intermittent electrical stimulation of the arcuate nucleus or of the medial preoptic area during 5-60 min, were accompanied by a marked rise in serum LH concentration. With arcuate stimulation, the rise in serum LH paralleled the increase in the fluorescence intensity of the nerve cell bodies, whereas with preoptic stimulation, the initial increase in cellular fluorescence intensity preceded the rise in serum LH. Preoptic stimulation also caused a moderate fall in pituitary LH which was simultaneous with the increase in fluorescence intensity. No systematic changes in FSH concentration were observed during the time interval studied.3. Pre-treatment with the tyrosine hydroxylase inhibitor alpha-methyltyrosine completely blocked the increase in fluorescence intensity caused by electrical stimulation of the arcuate nucleus but did not prevent the rise in serum LH.4. It is concluded that the tubero-infundibular dopamine neurones serve as an intermediary between the medial preoptic area (and possibly other forebrain structures) and neurones containing releasing factors. Under the present experimental conditions, stimulation of the tuberoinfundibular dopamine neurones increased the release of LH, probably by promoting the release of LH-releasing factor.