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Context: New animal welfare legislation and ethical guidelines encourage alternative approaches for canine contraception, instead of surgical gonadectomy which is considered invasive and unjustified in healthy dogs. Aims: Reversible contraception might be achieved by inhibition of aromatase (CYP19), an enzyme catalysing the conversion of androgens to oestrogens. This study provides insights into the spatio-temporal expression and distribution of aromatase in canine ovarian tissue. Methods: Ovarian tissue was collected from 39 healthy and sexually mature bitches during different stages of the oestrous cycle: pro-oestrus (n = 8), oestrus (n = 12), dioestrus (n = 9) (luteal phase) and anoestrus (n = 10). Localisation of cytochrome P450 aromatase was determined by immunohistochemistry. Key results: Aromatase activity in the dog is high during pro-oestrus, ovulation and early dioestrus. Comparing types of follicles and corpora lutea, the highest aromatase abundance was found in antral follicles and luteinising follicles, whereas corpora lutea and early antral follicles showed an intermediate presence of the enzyme. Interesting was the high abundance of aromatase in luteinising theca interna cells, prevailing over granulosa cells. Conclusions and implications: Understanding of cells involved in oestradiol production is important for targeted inhibition of oestradiol synthesis, possibly offering an approach for contraception and suppression of oestrus. In clinical practice, contraception in female dogs is traditionally achieved by surgical gonadectomy. As this method is discouraged by new animal welfare legislation in some parts of the world and is also related to several side effects, alternative possibilities for contraception are needed. Here, we report the distribution of aromatase in the canine ovary during different stages of the oestrous cycle. In-depth knowledge of oestrogen synthesis in the female dog is mandatory for targeted inhibition of oestradiol, possibly by the use of aromatase inhibitors. Photograph by M. P. Kowalewski. [ABSTRACT FROM AUTHOR]

The interest in non-surgical approaches to contraception and fertility control in female dogs has increased in recent years. In this study the effect of an aromatase inhibitor (finrozole) was evaluated in fur production animals, farmed blue fox vixens, as a model for contraception in bitches. A total of 80 vixens were divided into 4 groups, receiving orally placebo (A) or finrozole 0.5 mg/kg (B), 3.5 mg/kg (C) or 24.5 mg/kg (D) for 21 consecutive days beginning in the pre-ovulatory period of heat. Monitoring of the vixens included clinical signs of heat, measurement of vaginal electrical resistance (VER) as well as oestradiol and progesterone concentrations in plasma. The approximate relation of the start of treatment to ovulation varied from 11 days before to one day after ovulation provided that the LH peak occurred 0.5–2 days before the VER peak and ovulation was then estimated to occur 2 days after the LH peak. Seventy vixens were artificially inseminated within 8 h after a 50 Ω decline in vaginal electrical resistance was detected. Ten vixens were not inseminated. Pregnancy was confirmed by transabdominal ultrasound examination and birth of cubs was recorded. The pregnancy rates in the groups were 89.5% (A), 81.3% (B), 55.6% (C) and 52.9% (D). The average number of live born pups in the four groups was 9.4 (A), 7.0 (B), 5.8 (C), and 3.8 (D), respectively. No deleterious effects (for instance malformations) of finrozole on pups could be verified. The administration of finrozole did not have a significant effect on oestradiol parameters and VER values in vixens. Progesterone values were significantly higher in treatment groups compared with the placebo group. The results indicate that pregnancy could be avoided by finrozole provided that doses of ≥3.5 mg/kg were used and the treatment was initiated at least four days before the day of artificial insemination. This corresponds with two to six days before ovulation provided that the LH peak occurred 0.5–2 days before the VER peak and that ovulation then occurred in average 2 days after the LH peak. • Doses of ≥3.5 mg/kg of finrozole initiated at least four days before the first AI could completely prevent pregnancy. • Vixens that had not reached their oestradiol peak were susceptible to the finrozole treatment. • No deleterious effects (for instance malformations) of finrozole on cubs were observed in this study. [ABSTRACT FROM AUTHOR]

We show in this work how systems formed by phosphoproteins on calcium phosphate surfaces can be directly characterized, in real time, in liquid medium, without the need for elution or labeling. Specifically, we show how this is possible by applying three different techniques: ellipsometry, quartz crystal microbalance with dissipation, and atomic force microscopy-based friction force spectroscopy. We apply these techniques to study two different model systems, i.e. those formed upon the adsorption of two model phosphoproteins (κ- and β-casein) on hydroxyapatite (HA) surfaces. Information on the kinetics of adsorption, surface excess, viscoelasticity, water content, thickness of the layers, and protein-surface interaction is provided. Results indicate that both phosphoproteins form homogeneous elastic highly hydrated monolayers on the HA surfaces, the strength of β-casein layers being higher by approximately a factor of 4. Based on the experimental results, models for the conformation of κ- and β-casein molecules adsorbed on HA surfaces are proposed. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In Sweden, the National Board of Health and Welfare forecasts a decrease in dentists with 26% and an increase in dental hygienists with 47% until the year of 2023. This, together with changes in both epidemiology, especially of dental caries, and political priorities, calls for an effective and well-developed cooperation between dentists and dental hygienists in future dentistry. Hence, the aim of this project was to investigate whether highlighting teamwork during the undergraduate studies of dental students and dental hygiene students could improve the students' holistic view on patients as well as their knowledge of and insight into each other's future professions. Thirty-four dental students and 24 dental hygiene students participated in the study. At the beginning of their final year in undergraduate education, a questionnaire testing the level of knowledge of the dental hygienists' clinical competences was completed by both groups of students. In addition, activities intending to improve teamwork quality included the following: (i) a seminar with a dentist representing the Public Dental Health Services in Sweden, (ii) dental students as supervisors for dental hygiene students, (iii) planning and treatment for shared patients and (iv) students' presentations of the treatments and their outcomes at a final seminar. The project was ended by the students answering the above-mentioned questionnaire for the second time, followed by an evaluation of the different activities included in the study. The knowledge of dental hygienists' competences showed higher scores in almost all questions. Both groups of students considered the following aspects important: seminars with external participants, dental students acting as supervisors and planning and treating shared patients. By initiating and encouraging teamwork between dental students and dental hygiene students, it is possible to increase knowledge on dental hygienists' competence and also to develop and strengthen a holistic view on patients and dental work, thereby preparing both groups of students for their professional life. [ABSTRACT FROM AUTHOR]