The aim of our retrospective study was to determine significant differences of selected parameters between groups, divided according to the IFA titres (6 groups) and PCR positive result (one group) in attempt to improve current diagnostic and treatment criteria. Thrombocytopenia was the most prominent change in all positive dogs. There were significant differences only between each positive group compared to the control group. Our results showed the necessity of introducing additional diagnostic procedures in clinical practice to confirm the clinical relevance of exposure to A. phagocytophilum.
COBISS.SI-ID: 28169945
This study was conducted in collaboration with the Department of Reproduction, Obstetrics and Herd Health Faculty of Veterinary Medicine, Ghent Belgium. Associations between dairy herd management practices and both bacterial counts (BC) and coliform counts (CC) from 254 and 242 dairy herds in Flanders (Belgium), respectively, were studied. Data were analyzed using multivariable, multilevel linear regression analysis, allowing variance components analyses. Both BC and CC fluctuated throughout the year, although the milk quality parameters followed an opposite pattern. Multivariable, multilevel regression analysis revealed several management practices associated with either BC or CC. Increasing the cleaning frequency of the housing during wintertime under the Belgian weather conditions and implementing premilking teat disinfection before attaching the milking unit will likely result in lower BC values. Herds with a conventional milking parlor had substantially lower BC than herds where the cows were milked using an automatic milking system. Lower BC were observed when the dry cows were supplemented with a mix of minerals and vitamins, whereas in herds where prepartum heifers were often treated with antimicrobials before calving had a lower CC than farms where heifers were either not or only rarely treated. The variation in both BC and CC seems to be mainly determined by differences in management between the herds, as most variation in both parameters resided at the herd rather than at the observation level. Still, only a small proportion of the total variance was explained by factors capturing information related to the milking, herd health, and dry cow management, which suggests that the bacteriological milk quality and, in particular, CC is primarily driven by other factors than the ones included in this study.
COBISS.SI-ID: 3811706
Invited review article »Cooperation of sex chromosomal genes and endocrine influences for hypothalamic sexual differentiation," outlines findings that alter our concept/understanding of sexual differentiation of the brain. This paper presents the results of our own ongoing research work and findings of other research groups in the field; it illustrates the brain sexual differentiation from hormonal and sex chromosome perspective and discusses the influence of such differences on animal and human behavior. There have been occasional lively debates about the actual number of sexes that can be defined. However, there is little debate that mammalian sexual differentiation starts from the perspective of two primary sexes that correspond to differential sex chromosomes (X versus Y) that lead to individuals with sex typical characteristics, ranging from breast development and function, facial hair, different reproductive organs in humans, to larger body sizes in many mammals, presence or absence of antlers in ungulates, and differential plumage in birds. Beside obvious external differences, sex differences exist in many other organs or organ systems such as liver, immune system and brain. While sex chromosomes are usually credited as the key trigger for generating sex differences, most sex differences (at least in mammals) are thought to arise due to differential exposure to sex steroid hormones secreted by the gonads during development. In male mammals, the formation of the testis is triggered by the expression of the Sry gene on the Y chromosome. Sry gene induces a genetic cascade that leads gonadal primordia to develop into testes. Subsequently, testes secrete different hormones, key among them being the steroid hormone testosterone and the peptide anti-mullerian hormone, which are responsible for development of the male phenotype. While dogma states that ovaries develop in the absence of Sry gene, newer data indicate a critical genetic cascade for ovarian development. Although sex steroid hormones account for most aspects of brain sexual differentiation, a growing literature has raised important questions about the direct role of genes on sex chromosomes separate from sex steroid actions. Sex chromosomes obviously differ by sex, but it has been controversial as to what extent the genes on these chromosomes might affect brain development directly and differentially to cause differences in the brain between males and females.
COBISS.SI-ID: 3318906
EBI2 is GPCR that induces cell proliferation and strong G protein–coupled signalling similar to the oncogenic GPCRs CMV-US28 and HHV8-ORF74. It functions as a chemotactic receptor responding to a finely tuned distribution of its ligand, oxysterol 7?,25-OH, which binds to EBI2 with high affinity and selectivity. To elucidate the role of EBI2 in B-cell and lymphoma development, we generated transgenic C57BL/6 mice expressing human EBI2 (hEBI2) under the control of the IgH promoter and intronic enhancer to induce expression in B cells (designated IgH-hEBI2). Here, we show that B-cell–targeted expression of hEBI2 in mice not only leads to an expanded CD5+ B1a B-cell subset from a young age, but also development of a late-onset CLL-like disease with lymphomatous transformation and premature death. These findings are highly similar to those observed in CLL patients and identify EBI2 as a promoter of B-cell malignancies. As such, our findings may suggest that the phenotype of human CLL-causing cells is highly altered in secondary lymphoid organs as compared with the body cavities where the cells may initially accumulate to the highest degree. CLL currently stands as incurable despite the availability of effective first line therapies often capable of achieving complete clinical remission. Our findings highlight the possibility of a CLL precursor with a markedly different phenotype to that of the clinically recognized cells.
COBISS.SI-ID: 4246138
The molecular mechanisms that underlie spleen development and congenital asplenia, a condition linked to increased risk of overwhelming infections, remain largely unknown. The transcription factor TLX1 controls cell fate specification and organ expansion during spleen development, and Tlx1 deletion causes asplenia in mice. Deregulation of TLX1 expression has recently been proposed in the pathogenesis of congenital asplenia in patients carrying mutations of the gene-encoding transcription factor SF-1. Herein, we have shown that TLX1-dependent regulation of retinoic acid (RA) metabolism is critical for spleen organogenesis. In a murine model, loss of Tlx1 during formation of the splenic anlage increased RA signaling by regulating several genes involved in RA metabolism. Uncontrolled RA activity resulted in premature differentiation of mesenchymal cells and reduced vasculogenesis of the splenic primordium. Pharmacological inhibition of RA signaling in Tlx1-deficient animals partially rescued the spleen defect. Finally, spleen growth was impaired in mice lacking either cytochrome P450 26B1 (Cyp26b1), which results in excess RA, or retinol dehydrogenase 10 (Rdh10), which results in RA deficiency. Together, these findings establish TLX1 as a critical regulator of RA metabolism and provide mechanistic insights into the molecular determinants of human congenital asplenia. This article ranked among the ten most prominent research achievements of the University of Ljubljana in 2016.
COBISS.SI-ID: 4158330
Electrochemotherapy combined with peritumoural interleukin-12 (IL-12) gene electrotransfer was used for treatment of mast cell tumours in 18 client-owned dogs at the Clinic for Small animals of Veterinary faculty Ljubljana. Local tumour control, recurrence rate, as well as safety of combined therapy were evaluated. One month after the therapy, no side effects were recorded and good local tumour control was observed with high complete responses rate (66%), which even increased during the observation period to 72%. IL-12 gene electrotransfer resulted in detectable serum IFN- and/or IL-12 levels in 78% of patients. In the treated tumours vascular changes as well as minimal T-lymphocytes infiltration was observed. After 1 week, the plasmid DNA was not detected intra- or peritumorally and no horizontal gene transfer to commensal bacteria was observed. In summary, our study demonstrates high antitumour efficacy of electrochemotherapy combined with IL-12 electrotransfer, which also prevented recurrences or distant metastases, as well as its safety and feasibility in treatment of canine mast cell tumours. Meaning and usability: Electrochemotherapy and electro genetherapy have proved to be very effective and safe for the treatment of tumours in dogs. The successfulness of the therapy is specially appreciated in tumours, which are too big for the surgical removal or are not responsive to standard chemotherapy. Application of these therapies on veterinary patients serves as a translational model for humans. This article was ranked among the five most prominent research achievements selected within the project Excellence in Science in field of biotechnological science in 2017.
COBISS.SI-ID: 2248059
This work was aimed to reveal mechanisms responsible for the respiratory arrest induced by cytolytic complex OlyA/PlyB (Ostreolysin), isolated from edible oyster mushrooms (Pleurotus ostreatus). Previous studies have demonstrated that at low concentrations Ostreolysin causes acute respiratory arrest in rats. Based on that two hypotheses were postulated: i) Ostreolysin produces swelling of neuroblastoma NG108-15 cells; and ii) Ostreolysin increases the neuronal intracellular Ca2+ activity. Experiments were performed on differentiated neuronal cells using confocal microscopy and spectrofluorometry to reveal changes in morphology and intracellular Ca2+ activity, respectively. Ostreolysin affected the neuronal cells morphology and increased the intracellular Ca2+ activity that could lead to neuronal dysfunction and respiratory arrest. Using pharmacological tools, the possible mechanisms underlying this toxic action were then described. These observations are important steps toward understanding the toxic respiratory effects of the Ostreolysin. This article was ranked among the five most prominent research achievements selected within the project Excellence in Science in field of biotechnological science in 2016.
COBISS.SI-ID: 3944570
Glucose metabolism is under the cooperative regulation of both insulin receptor (IR) and ß2-adrenergic receptor ß2AR, which represent the receptor tyrosine kinases (RTKs) and seven transmembrane receptors (7TMRs), respectively. Studies demonstrating cross-talk between these two receptors and their endogenous coexpression have suggested their possible interactions. To evaluate the effect of IR and prospective heteromerization on ß2AR properties, we showed that IR coexpression had no effect on the ligand binding properties of ß2AR; however, IR reduced ß2AR surface expression and accelerated its internalization. Additionally, both receptors displayed a similar distribution pattern with a high degree of colocalization. To test the possible direct interaction between ß2AR and IR, we employed quantitative BRET2 saturation and competition assays. Saturation assay data suggested constitutive ß2AR and IR homo- and heteromerization. Calculated acceptor/donor (AD50) values as a measure of the relative affinity for homo- and heteromer formation differed among the heteromers that could not be explained by a simple dimer model. In heterologous competition assays, a transient increase in the BRET2 signal with a subsequent hyperbolical decrease was observed, suggesting higher-order heteromer formation. To complement the BRET2 data, we employed the informational spectrum method (ISM), a virtual spectroscopy method to investigate protein-protein interactions. Computational peptide scanning of ß2AR and IR identified intracellular domains encompassing residues at the end of the 7th TM domain and C-terminal tail of ß2AR and a cytoplasmic part of the IR ß chain as prospective interaction domains. ISM further suggested a high probability of heteromer formation and homodimers as basic units engaged in heteromerization. In summary, our data suggest direct interaction and higher-order ß2AR:IR oligomer formation, likely comprising heteromers of homodimers.
COBISS.SI-ID: 3896954
Fezf1 gene has been identified in the present study as a regulator of female sexual behavior in mice. Regulation of the female sexual behavior could be through the regulation of estrogen receptor alpha expression in the ventromedial nucleus of the hypothalamus, as the expression of this receptor was reduced in mice with downregulated Fezf1. As expression of Fezf1 is very specific in the brain, this gene could present a potential target for the development of novel drugs regulating hypoactive sexual desire disorder in women, if similar function of FEZF1 will be confirmed in humans.
COBISS.SI-ID: 4402298
Long-term selection of modern pig breeds not only resulted in high growth rates and muscle hypertrophy, but also lowers meat quality, which is as an important issue in meat-producing animals. Therefore, the aim of this study was to elucidate the influence of domestication on the myofiber types formation, with the emphasize on the age-dependent myosin heavy chain isoform (MyHC) expression in the myofibers. In summary, the comparison of growing domestic and wild pigs showed that domestication and programmed selection lead to substantial changes in the direction and intensity of postnatal MyHC transformation in the pig longissimus muscle. In the domestic pig, the transformation of MyHC was shifted towards myofibers that expressed MyHC –IIb, which resulted in accelerated myofiber hypertrophy with glycolytic metabolic properties of the muscle as a whole. In the wild pig the maturation of the longissimus muscle was characterized by a faster elimination of foetal MyHC and differentiation towards oxidative myofibers in which type I, IIa and IIx MyHCs prevailed. The myofiber hypertrophy was intensive especially from 3 weeks until 7 months of age. In this period, the myofiber cross sectional area increased up to 10- and 20-fold in the wild and the domestic pig, respectively. In the domestic pig particularly, the hypertrophy of the myofibers in which MyHC -IIx and -IIb was most distinctive. The results of the study significantly contribute to the understanding of the cell mechanisms of muscle tissue formation in pig and could help to design adequate pig breeding programme that would allow finding appropriate balance between growth performance, muscularity and meat quality.
COBISS.SI-ID: 5050472