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Objective: Cognitive impairments (CI) have recently been identified in canine epilepsy patients. A medium-chain triglyceride (MCT) enriched diet has been demonstrated to improve cognition in aged dogs and seizure control in canine epilepsy. This study evaluates the short-term effects of MCT oil consumption on cognitive abilities in dogs with epilepsy, a naturally occurring animal model.\ud \ud Methods: A 6-month multi-center, prospective, randomized, double-blinded, controlled cross-over diet trial was conducted comparing dietary supplementation (DS) of MCT-oil to a control oil. Allocation to dietary oil supplements, consisting of 9% total caloric intake, was block-randomized and supplemented into each dogs’ diet for three months followed by a respective switch of DS oil for a further three months. Non-invasive cognitive tests and a validated psychometric tool were utilized to evaluate cognitive function and perturbations associated with dietary intervention.\ud \ud Results: Twenty-nine dogs completed the trial, of which 18 completed non-invasive cognitive testing. Spatial-working memory (p=0.008), problem-solving ability (p=0.048) and owner-reported trainability (p=0.041) were significantly improved during MCT-oil supplementation compared to control-DS. \ud \ud Significance: MCT-oil DS improves cognition in dogs with epilepsy when compared to a control-DS. MCT supplementation may represent a promising option to address CI associated with epilepsy.

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Atmospheric new-particle formation (NPF) affects climate by contributing to a large fraction of the cloud condensation nuclei (CCN). Highly oxygenated organic molecules (HOMs) drive the early particle growth and therefore substantially influence the survival of newly formed particles to CCN. Nitrogen oxide (NOₓ) is known to suppress the NPF driven by HOMs, but the underlying mechanism remains largely unclear. Here, we examine the response of particle growth to the changes of HOM formation caused by NOₓ. We show that NOₓ suppresses particle growth in general, but the suppression is rather nonuniform and size dependent, which can be quantitatively explained by the shifted HOM volatility after adding NOₓ. By illustrating how NOₓ affects the early growth of new particles, a critical step of CCN formation, our results help provide a refined assessment of the potential climatic effects caused by the diverse changes of NOₓ level in forest regions around the globe.

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Epaxial muscle atrophy is related to spinal diseases in dogs. However, the influence of intervertebral disc herniation (IVDH) on the functional capacity of epaxial muscles has not been investigated. We aimed to estimate force and power-generating capacity of epaxial muscles in chondrodystrophic Dachshunds and non-chondrodystrophic Border terriers bred for similar purposes. Further we aimed to compare these features in Dachshunds with and without IVDH. Cadavers of Dachshunds (n = 16) and Border terriers (n = 7) were investigated with MRI. In the absence of clinical information, MRI findings were used to categorize the Dachshunds into affected (n = 8) and non-affected (n = 8). Epaxial muscle mass, muscle belly length, fascicle length, architectural index and physiological cross-sectional area (PCSA) were obtained through dissections, pain and exercise history through questionnaires. Difference between groups and effect of covariates were assessed with ANCOVA models. Dachshunds had greater muscle mass in M. splenius, M. longissimus capitis and M. iliocostalis thoracis (all P

A recent CLOUD (Cosmics Leaving OUtdoor Droplets) chamber study showed that sulfuric acid and dimethylamine produce new aerosols very efficiently, and yield particle formation rates that are compatible with boundary layer observations. These previously published new particle formation (NPF) rates are re-analyzed in the present study with an advanced method. The results show that the NPF rates at 1.7 nm are more than a factor of 10 faster than previously published due to earlier approximations in correcting particle measurements made at larger detection threshold. The revised NPF rates agree almost perfectly with calculated rates from a kinetic aerosol model at different sizes (1.7 nm and 4.3 nm mobility diameter). In addition, modeled and measured size distributions show good agreement over a wide range (up to ca. 30 nm). Furthermore, the aerosol model is modified such that evaporation rates for some clusters can be taken into account; these evaporation rates were previously published from a flow tube study. Using this model, the findings from the present study and the flow tube experiment can be brought into good agreement. This confirms that nucleation proceeds at rates that are compatible with collision-controlled (a.k.a. kinetically-controlled) new particle formation for the conditions during the CLOUD7 experiment (278 K, 38% RH, sulfuric acid concentration between 1×106 and 3×107 cm-3 and dimethylamine mixing ratio of ~40 pptv). Finally, the simulation of atmospheric new particle formation reveals that even tiny mixing ratios of dimethylamine (0.1 pptv) yield NPF rates that could explain significant boundary layer particle formation. This highlights the need for improved speciation and quantification techniques for atmospheric gas-phase amine measurements.

Background In the last decade, a disorder characterized by episodes of involuntary movements and dystonia has been recognized in Border Terriers. Objectives To define clinical features of paroxysmal dyskinesia (PD) in a large number of Border Terriers and to study the genetics of the disease. Animals 110 affected and 128 unaffected client-owned Border Terriers. Methods A questionnaire regarding clinical characteristics of PD was designed at Utrecht University and the University of Helsinki. Thirty-five affected Border Terriers underwent physical examination and blood testing (hematology and clinical biochemistry). Diagnostic imaging of the brain was performed in 17 affected dogs and electroencephalograms (EEG) between episodes were obtained in 10 affected dogs. A genomewide association study (GWAS) was performed with DNA of 110 affected and 128 unaffected dogs. Results One hundred forty-seven questionnaires were included in the study. The most characteristic signs during episodes were dystonia, muscle fasciculations, and falling over. The majority of owners believed that their dogs remained conscious during the episodes. A beneficial effect of anti-epileptic therapy was observed in 29 of 43 dogs. Fifteen owners changed their dogs’ diet to a hypoallergenic, gluten-free diet, and all reported reasonable to good improvement of signs. Clinical examinations and diagnostic test results were unremarkable. The GWAS did not identify significantly associated chromosome regions. Conclusions and Clinical Importance The survey results and EEG studies provided further evidence that the observed syndrome is a PD rather than epilepsy. Failure to achieve conclusive results by GWAS indicates that inheritance of PD in Border Terriers probably is complex.

Leucine-rich glioma-inactivated (LGI) protein was first thought to have a suppressor effect in the formation of some cancers. Developments in physiology and medicine made it possible to characterize the function of the LGI protein family and its crucial role in different conditions more precisely. These proteins play an important role in synaptic transmission, and dysfunction may cause hyperexcitability. Genetic mutation of LGI1 was confirmed to be the cause of autosomal dominant lateral temporal lobe epilepsy in humans. The LGI2 mutation was identified in benign familial juvenile epilepsy in Lagotto Romagnolo (LR) dogs. Cats with familial spontaneous temporal lobe epilepsy have been reported, and the etiology might be associated with LGI protein family dysfunction. In addition, an autoimmune reaction against LGI1 was detected in humans and cats with limbic encephalitis. These advances prompted a review of LGI protein function and its role in different seizure disorders.

Oxidation processes in Earth's atmosphere are tightly connected to many environmental and human health issues and are essential drivers for biogeochemistry. Until the recent discovery of the atmospheric relevance of the reaction of stabilized Criegee intermediates (sCIs) with SO2, atmospheric oxidation processes were thought to be dominated by a few main oxidants: ozone, hydroxyl radicals (OH), nitrate radicals and, e.g. over oceans, halogen atoms such as chlorine. Here, we report results from laboratory experiments at 293 K and atmospheric pressure focusing on sCI formation from the ozonolysis of isoprene and the most abundant monoterpenes (α-pinene and limonene), and subsequent reactions of the resulting sCIs with SO2 producing sulfuric acid (H2SO4). The measured total sCI yields were (0.15 ± 0.07), (0.27 ± 0.12) and (0.58 ± 0.26) for α-pinene, limonene and isoprene, respectively. The ratio between the rate coefficient for the sCI loss (including thermal decomposition and the reaction with water vapour) and the rate coefficient for the reaction of sCI with SO2, k(loss) /k(sCI + SO2), was determined at relative humidities of 10 and 50%. Observed values represent the average reactivity of all sCIs produced from the individual alkene used in the ozonolysis. For the monoterpene-derived sCIs, the relative rate coefficients k(loss) / k(sCI + SO2) were in the range (2.0–2.4) × 1012 molecules cm−3 and nearly independent of the relative humidity. This fact points to a minor importance of the sCI + H2O reaction in the case of the sCI arising from α-pinene and limonene. For the isoprene sCIs, however, the ratio k(loss) / k(sCI + SO2) was strongly dependent on the relative humidity. To explore whether sCIs could have a more general role in atmospheric oxidation, we investigated as an example the reactivity of acetone oxide (sCI from the ozonolysis of 2,3-dimethyl-2-butene) toward small organic acids, i.e. formic and acetic acid. Acetone oxide was found to react faster with the organic acids than with SO2; k(sCI + acid) / k(sCI + SO2) = (2.8 ± 0.3) for formic acid, and k(sCI + acid) / k(sCI + SO2) = (3.4 ± 0.2) for acetic acid. This finding indicates that sCIs can play a role in the formation and loss of other atmospheric constituents besides SO2.

Mobilimainonta on vielä tälläkin hetkellä suhteellisen vähän tutkittu aihealue tiedemaailmassa. Mobiililaitteiden hurja suosio ei ole vielä aiheuttanut täydellistä läpimurtoa mobiilimainnonnassa. Ei olla onnistuttu löytämään sellaista ratkaisua, joka tyydyttäisi niin mainostajia, kuin niiden vastaanottajiakin. Tästä syystä tämä tutkimus on aiheellinen. Tutkimusta varten tehtiin kirjallisuuskatsaus käytettävyydestä ja sen arvioinnista, mainonnan eri muodoista, kuten mobiilimainoksista sekä mobiilikäyttöliittymien suunnittelusta. Kirjallisuuskatsauksen jälkeen suoritettiin käytettävyystestaus. Lopuksi teoriataustan sekä käytettävyystestauksesta kerätyn datan avulla suoritettiin analyysi. Käytettävyystestauksessa testattiin neljää eri mainosta, joista kaksi saapui puhelimeen lähetetyn tekstiviestin jälkeen ja kaksi vastaamatta jätetyn puhelun jälkeen. Näistä mainoksista osa oli kontekstisidonnaisia ja osa käyttökontekstista riippumattomia. Käytettävyystestaus suoritettiin kesällä 2010. Käytettävyystestauksen myötä havaittiin, että ihmiset suhtautuvat mobiilimainoksiin hyvin eri tavoilla. Jotkut vastaanottaisivat mielellään mainoksia puhelimeensa, kun taas joillekin ne tuntuivat melko epämiellyttäviltä. Tärkeimpinä tuloksina tutkimuksesta voidaan pitää sitä, että sen myötä havaittiin olevan tilausta tietynlaisille mobiilimainoksille, sekä se, että mainosten kontekstisidonnaisuudella oli suuri vaikutus mainoksen koettuun miellyttävyyteen, sekä tehoon. Lisäksi havaittiin, että mobiilimainoksilla voi olla myös hyvin negatiivinen vaikutus vastaanottajissa.