Heart rate variability in Konik and purebred Arabian horses in response to different predator vocalisations.

The current predation threat of domestic horses is generally low, and horses do not know predators' frightening cues. We studied whether horses still recognise predation threats. The aim of the study was to analyse the emotional response of purebred Arabian horses (Arabian) and Polish Konik horses (Konik) to an Arabian panther (Panthera pardus nimr) (panther) growl and a grey wolf (Canis lupus) (wolf) howl. Panther vocalisation was known to Arabian ancestors, whereas ancestors of Konik knew wolf vocalisation. The response to the howls of golden jackals (Canis aureus) (jackal), which did not prey on equids, was also studied comparatively. Two groups of 10 adult horses of each breed were subject to predator sounds of one predator daily for 5 min during a turn out on pasture. The test was performed for 18 days in total. The sound of each predator was interchangeably featured from one loudspeaker for 3 days followed by four loudspeakers simultaneously to imitate a group of predators for 3 days. The horses' emotional agitation in response to the sounds was measured based on the parameters of heart rate variability (HRV) using telemetric devices. The results showed that the predators' sounds were identified by horses as stressful or neutral. Horses generally retained their anti-predator responses even in the current habitat, which typically lacks predation cues. The results are not always coherent and may demonstrate that the response is somewhat attenuated. The wolf howl elicited a stronger response in Koniks. The panther growl more strongly influenced Arabians, whereas the jackal howl minimally elicited an agitation in the horses. The differentiated response of the two horse breeds to the three predator species suggests that the response is an innate adaptation to the predation risk in the habitat of the breed ancestors. This response occurs regardless of the emotional arousal specific to a breed, and the frightening cue is not the sound per se but the possible attack of predators. Horses display a type of understanding of the sound meaning. Their HRV response seems to be adequate for the threat signalised by the sound.

Expression and activity of collagenases in the digital laminae of horses with carbohydrate overload-induced acute laminitis.

BACKGROUND: Matrix metalloproteinases (MMP) are hypothesized to degrade structurally important components of the laminar extracellular matrix (ECM) in horses with laminitis. OBJECTIVE: To compare levels of expression of stromelysin-1 (MMP-3), collagenases (MMP-1, -13), and membrane type-MMPs (MMP-14, -15, -16), and the distribution of their ECM substrates, in laminae of healthy horses and horses with carbohydrate overload laminitis. ANIMALS: Twenty-five adult horses. METHODS: Gene and protein expression were determined in extracts of laminae using real-time quantitative polymerase chain reaction and Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis. Distribution of MMP-13 and ECM components was determined using indirect immunofluorescent microscopy of nonfixed frozen sections. ECM morphology was assessed by hematoxylin and eosin staining. RESULTS: Of the genes studied, only those encoding MMP-1 and -13 were upregulated in CHO-induced laminitis; MMP-1 at Obel grade (OG)1 lameness and MMP-13 at OG3 lameness. Laminar MMP-1 was present as 52 kDa proenzyme only. MMP-13 was present as pro- (61 kDa) and processed (48 kDa) enzyme. MMP-13 localized to the basal epithelium of the secondary epidermal laminae and its increased expression were accompanied by the appearance in secondary dermal laminae (SDL) of multiple foci that were devoid of collagen I, fibronectin, chondroitin and keratan sulfate glycosaminoglycans, and eosin-staining material. CONCLUSIONS AND CLINICAL RELEVANCE: MMP-13 is upregulated in laminae of horses with CHO-induced OG3 lameness and, by degrading components of the ECM, may contribute to the formation of ECM-free lesions (gaps or tears) that appear in the SDL with OG3 lameness.

Regulation of hypoxia-inducible factor-1α and related genes in equine digital lamellae and in cultured keratinocytes.

REASONS FOR PERFORMING STUDY: Hypoxia-inducible factor-1α (HIF-1A) is an important protein in the regulation/induction of many genes in the cellular and tissue response to hypoxia and a central mediator in inflammatory signalling. As both hypoxia and inflammatory events are purported to occur in the lamellar epidermis in sepsis-related laminitis in the equid, HIF-1A may play a central role in this disease process. OBJECTIVESS: To assess the regulation of HIF-1A and HIF-1A-related genes in the equine keratinocyte in vitro and in the lamellar tissue of horses with sepsis-related laminitis. STUDY DESIGN: In vivo and in vitro experiments. METHODS: Real-time quantitative PCR (RT-qPCR) and immunoblotting were performed to assess the mRNA and protein concentrations of HIF-1A and the mRNA concentrations of HIF-1A-related genes in cultured equine keratinocytes and in lamellar samples from black walnut extract (BWE)- and carbohydrate overload (CHO)-induced laminitis. Hypoxia-inducible factor-1α was further localised via indirect immunofluorescence in frozen lamellar tissue sections. RESULTS: Hypoxia-inducible factor-1α appears to be regulated primarily at the post transcriptional level in the cultured equine keratinocyte, resulting in increased HIF-1A in response to hypoxia but not to lipopolysaccharide exposure. Hypoxia-inducible factor-1α is present at high concentrations in the normal equine lamina, and is increased in Obel grade 1 (OG1) stage laminitis in the CHO model of laminitis. Equine lamellar mRNA concentrations of cyclo-oxygenase-2 and inducible nitric oxide synthase, but not glucose transporter 1, are increased in the BWE and CHO models of laminitis. CONCLUSIONS AND POTENTIAL RELEVANCE: These data indicate that the normal equine lamellae are profoundly hypoxic in comparison with other tissues. The increased mRNA concentrations of cyclo-oxygenase-2 and inducible nitric oxide synthase 2 in equine keratinocytes exposed to hypoxia and lipopolysaccharide, and in lamellar tissue from BWE and CHO models of sepsis-related laminitis, suggest that the marked lamellar inflammatory gene expression in sepsis-related laminitis may be due to an interaction of constitutively high lamellar keratinocyte HIF-1A signalling with inflammatory signalling, possibly induced by circulating inflammatory mediators.

Association studies of CTLA-4, CD28, and ICOS gene polymorphisms with B-cell chronic lymphocytic leukemia in the Polish population.

Abnormal expression of the costimulatory molecules cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD28, and inducible co-stimulator (ICOS) leads to disturbances of immune response and an increased risk of cancer. An extended study was undertaken to evaluate the association among the polymorphisms CTLA-4c.49A>G, CTLA-4g.319C>T, CTLA-4g.*642AT(8_33), CD28c.17+3T>C, and ICOSc.1554+4GT(8_15) and susceptibility to B-cell chronic lymphocytic leukemia (B-CLL) in the Polish population. The study revealed increased frequency of the CTLA-4g.319C>T [T] allele and the CTLA-4g.319C>T [T] phenotype in B-CLL patients compared with healthy controls (p = 0.003, odds ratio [OR] = 1.73; and p = 0.009, OR = 1.74, respectively). The presence of the CD28c.17+3T>C [C] allele and the CD28c.17+3T>C [C] phenotype increased the OR of B-CLL to 1.59 (p = 0.007) and 1.74 (p = 0.007), respectively. Either CTLA-4g.319C>T or CD28c.17+3T>C was associated with time to Rai stage progression. The distributions of the alleles and genotypes of the ICOS gene significantly differed between patients and controls (p = 0.0009 and p = 0.006, respectively). Individuals possessing short alleles were 2.02 times more prone to B-CLL than others (p = 0.001), whereas carriers of long alleles were protected from B-CLL (p = 0.02, OR = 0.62). The haplotype association study and multivariate analysis confirmed the association of CTLA-4g.319C>T and ICOSc.1554+4GT(8_15) gene polymorphisms with B-CLL. The polymorphic sites CTLA-4c.49A>G and CTLA-4g.*642AT(8_33) did not correlate with B-CLL. Our results are the first in the literature to report that gene polymorphism of the costimulatory molecules CTLA-4, CD28, and ICOS contributes to susceptibility to B-CLL.

Different patterns of activation markers expression and CD4+ T-cell responses to ex vivo stimulation in patients with clinically quiescent multiple sclerosis (MS).

Patients with relapsing-remitting (RR) and secondary progressive (SP) forms of multiple sclerosis (MS), although in long-term clinical remission, showed different patterns of increased expressions of the activation markers: CD69, CD40L, and both membrane/surface and cytoplasmic CTLA-4 (mCTLA-4 and cCTLA-4, respectively) in freshly isolated peripheral blood (PB) CD4+ T cells compared with controls. Also observed were dysregulated responses to ex vivo stimulation in both groups of MS patients accompanied by increased IFN-gamma synthesis. Our findings may suggest that the mechanisms leading to each clinical form of the disease may be heterogeneous.

Stochastic model of ultrafine particle deposition and clearance in the human respiratory tract.

Deposition and clearance of insoluble ultrafine particles, ranging from 1 to 100 nm, were simulated by stochastic models using Monte Carlo methods. Brownian motion is the dominant mode of deposition in human airways. The additional effects of convective diffusion in bifurcations and axial diffusion (convective mixing) primarily affect particle transport and deposition of particles in the 1-10 nm range. Regarding total deposition, the effects of both convective mechanisms are practically compensated by the concomitant effect of molecular radial diffusion (Brownian motion). During the first hours following inhalation, 1 nm particles are predicted to be cleared much faster than particles in the size range from 10 to 100 nm, with a retained fraction of about 80% after 24 h. For 1-10 nm particles, extracellular transfer to blood is the most likely mode of clearance, while uptake and subsequent accumulation in epithelial cells are assumed to be the preferential mechanisms for 10-100 nm particles.

Temozolomide induces apoptosis and senescence in glioma cells cultured as multicellular spheroids.

Temozolomide is an alkylating cytostatic drug that finds increasing application in the treatment of melanoma, anaplastic astrocytoma and glioblastoma multiforme. The compound is a prodrug that decomposes spontaneously, independent of an enzymatic activation step. DNA methylation induces futile mismatch repair cycles and depletion of the DNA repair enzyme O(6)-methylguanine-DNA methyltransferase should then initiate programmed cell death. We show drug-dependent inhibition of tumour growth in a three-dimensional cell culture model of the glioma cell lines U87MG and GaMG. Migrational behaviour of the glioblastoma cells remained unaltered. However, coincubation of tumour spheroids with primary brain aggregates showed reduced tumour cell invasion into brain tissue in the presence of temozolomide. This was not achieved by slowing cellular migration, as temozolomide-treated cells displayed no reduced motility. By transferase-mediated dUTP nick-end labelling (TUNEL) of apoptotic nuclei, we found that the drug was able to induce apoptosis throughout the tumour cell spheroids. Apoptosis was highest in the core region of the spheroids. Repetitive application of sublethal doses of temozolomide to multicellular spheroids resulted in the development of drug resistance in GaMG cells. We suggest that temozolomide is a strong initiator of apoptosis in glioblastoma tumour cells in a spheroid cell culture system, when cells are already in a stressful environment.

1,25(OH)2 vitamin D concentration in the plasma of Solanum glaucophyllum intoxicated rabbits.

OBJECTIVE: To test Solanum glaucophyllum calcinotic effects in adult New Zealand White rabbits in relation to cumulative dose and active principle concentration in plasma. DESIGN: An intoxication assay with controls. PROCEDURE: Rabbits were orally dosed with aqueous extracts of dry leaves of S glaucophyllum for 5, 7 or 9 days. During the experiment, body weight, calcaemia and phosphataemia were measured; retinal blood vessel calibre was observed by ophthalmoscopic examination of the ocular fundus. 1,25(OH)2 vitamin D plasma concentration was determined at the end of the experimental periods. Soft tissue calcium concentration and the presence of calcinotic lesions were studied after euthanasia. RESULTS: Toxic effects were evident in S glaucophyllum treated groups (loss of body weight, elevation of soft tissue calcium concentration, and presence of calcinotic lesions). Plasma 1,25(OH)2 vitamin D concentrations were negatively correlated with final body weight (r = -0.97; P < or = 0.001), and positively correlated with renal calcium concentration (r = 0.74; P = 0.02). There was also a significant regression of plasma 1,25 (OH)2 vitamin D concentration on the cumulative dose of S glaucophyllum (R2 = 0.87; P < or = 0.001). CONCLUSIONS: The procedure described here offers a sensitive and practical experimental model for the study of the pathogenesis of enteque seco.

Neutron activation analysis of Se in bovine plasma samples.

Elemental concentration of selenium in bovine plasma at parts-per-billion levels was determined using radiochemical neutron activation analysis (RNAA). This study was connected with the relation between the Enteque Seco, a toxic bovine calcinosis, and the Se status. The technique developed is based on the coprecipitation of Se with HgS. Good agreement with certified reference materials have been found. The values for the Se contents in normal bovine samples were in concordance with literature values.

Annual and weekly changes in the sleep-wake rhythm of school children.

Sleep-wake patterns in 10- and 14-year-old children were followed over a year using sleep diaries kept during 2-week periods every 5 weeks. The times of awakening and sleep duration closely followed the annual and weekly alternations of schooldays and holidays. During vacations, sleep duration increased considerably as compared to the school year. The clear decrease in sleep duration was observed in spring only for 14-year-olds. Weekly changes of sleep patterns during the school year disappeared during vacations. It was concluded that sleep duration in children is closely related to the school schedules and could be a result of sleep deprivation and recovery.

The politics of cutback management.

Health and social service organizations in the United States are experiencing decline in financial resources. Little is known about the management of such decline. Forty-three executives of health and human service organizations were interviewed to study their experience with cutback management. The political strategies used by the executives to cope with cutbacks are described.

Gel with nystatin for treatment of lung mycosis.

A method of preparation of the gel with nystatin for a local treatment of lung mycosis is described. Physico-chemical properties and the stability of this preparation have been investigated.