Rabbit models of heart disease.

Human heart disease is a major cause of death and disability. A variety of animal models of cardiac disease have been developed to better understand the etiology, cellular and molecular mechanisms of cardiac dysfunction and novel therapeutic strategies. The animal models have included large animals (e.g. pig and dog) and small rodents (e.g. mouse and rat) and the advantages of genetic manipulation in mice have appropriately encouraged the development of novel mouse models of cardiac disease. However, there are major differences between rodent and human hearts that raise cautions about the extrapolation of results from mouse to human. The rabbit is a medium-sized animal that has many cellular and molecular characteristics very much like human, and is a practical alternative to larger mammals. Numerous rabbit models of cardiac disease are discussed, including pressure or volume overload, ischemia, rapid-pacing, doxorubicin, drug-induced arrhythmias, transgenesis and infection. These models also lead to the assessment of therapeutic strategies which may become beneficial in human cardiac disease

An integrative description of a new Richtersius species from Greece (Tardigrada: Eutardigrada: Richtersiusidae)

In this paper, we describe a new tardigrade species, Richtersius tertius sp. n., from Greece. The description is based on morphological and morphometric analysis using light and scanning electron microscopy as well as genetic analysis based on four molecular markers (DNA sequences of three nuclear, i.e., 18S rRNA, 28S rRNA, ITS-2 and one mitochondrial COI fragment). Morphological and morphometric differences, together with genetic comparisons, provide independent verifications of Richtersius tertius sp. n. as a species new to science. Phenotypically, the new taxon differs from Richtersius coronifer (Richters, 1903) and Richtersius ziemowiti Kayastha, Berdi, Miaduchowska, Gawlak, Łukasiewicz, Gołdyn, Jędrzejewski et Kaczmarek, 2020 mainly by the morphology and size of cuticular pores, present only in hatchlings (first instars), as well as some morphometric characters. The results presented herein contribute further to the recognition of the morphological variability and biodiversity within Richtersius, with Richtersius tertius sp. n. being the third species formally described within the genus

Sprawozdanie z konferencji "Symposium etymologicum. Śladami myśli etymologicznej"

Report from the conference Symposium etymologicum. Tracing etymological thoughtThe article is a report from the conference Symposium etymologicum. Śladami myśli etymologicznej (Symposium etymologicum. Tracing etymological thought), which was held in Kraków on 27–29 May 2016. The Symposium etymologicum is a recurring international conference focusing on diachronic linguistics and especially etymology, a part of a series of etymological conferences organized under the auspices of the Etymological Commission of the International Committee of Slavists. The May 2016 Symposium, aside its usual goal of allowing for exchange of views between representative of various linguistics institutions, aimed to honour the memory of the prominent Slavist and etymologist – a full member of the Committee on Linguistics of the Polish Academy of Sciences – Professor Franciszek Sławski on the occasion of the 100th anniversary of his birth. Sprawozdanie z konferencji Symposium etymologicum. Śladami myśli etymologicznejArtykuł stanowi sprawozdanie z konferencji Symposium etymologicum. Śladami myśli etymologicznej, która odbyła się w Krakowie w dniach 27–29 maja 2016 roku. Symposium etymologicum to międzynarodowa konferencja naukowa o profilu diachronicznym ze szczególnym uwzględnieniem etymologii, wchodząca w cykl konferencji etymologicznych organizowanych pod patronatem Komisji Etymologicznej przy Międzynarodowym Komitecie Slawistów. Symposium z maja 2016 roku, poza celem merytorycznym, czyli wymianą poglądów między reprezentantami różnych ośrodków językoznawczych, miało również uczcić pamięć wybitnego slawisty i etymologa – członka rzeczywistego Komitetu Językoznawstwa PAN – prof. dr. hab. Franciszka Sławskiego w stulecie jego urodzin

Sprawozdanie z konferencji "Symposium etymologicum. Śladami myśli etymologicznej"

Report from the conference Symposium etymologicum. Tracing etymological thought The article is a report from the conference Symposium etymologicum. Śladami myśli etymologicznej (Symposium etymologicum. Tracing etymological thought), which was held in Kraków on 27–29 May 2016. The Symposium etymologicum is a recurring international conference focusing on diachronic linguistics and especially etymology, a part of a series of etymological conferences organized under the auspices of the Etymological Commission of the International Committee of Slavists. The May 2016 Symposium, aside its usual goal of allowing for exchange of views between representative of various linguistics institutions, aimed to honour the memory of the prominent Slavist and etymologist – a full member of the Committee on Linguistics of the Polish Academy of Sciences – Professor Franciszek Sławski on the occasion of the 100th anniversary of his birth.   Sprawozdanie z konferencji Symposium etymologicum. Śladami myśli etymologicznej Artykuł stanowi sprawozdanie z konferencji Symposium etymologicum. Śladami myśli etymologicznej, która odbyła się w Krakowie w dniach 27–29 maja 2016 roku. Symposium etymologicum to międzynarodowa konferencja naukowa o profilu diachronicznym ze szczególnym uwzględnieniem etymologii, wchodząca w cykl konferencji etymologicznych organizowanych pod patronatem Komisji Etymologicznej przy Międzynarodowym Komitecie Slawistów. Symposium z maja 2016 roku, poza celem merytorycznym, czyli wymianą poglądów między reprezentantami różnych ośrodków językoznawczych, miało również uczcić pamięć wybitnego slawisty i etymologa – członka rzeczywistego Komitetu Językoznawstwa PAN – prof. dr. hab. Franciszka Sławskiego w stulecie jego urodzin

Isolated Potentials and Pace-Mapping as Guides for Ablation of Ventricular Tachycardia in Various Types of Nonischemic Cardiomyopathy

Nonischemic Cardiomyopathy and Ventricular Tachycardia.    Background : In patients with prior infarction, isolated potentials (IPs) during sinus rhythm reflect fixed scar and often indicate sites critical for ventricular tachycardia (VT). The purpose of this study was to determine the value of IPs in conjunction with pace-mapping to guide VT ablation in patients with various types of nonischemic cardiomyopathy. Methods : Mapping and ablation of VT were performed in 35 consecutive patients (26 men, age 55 ± 13 years, ejection fraction 0.31 ± 0.14) with VT and various etiologies of nonischemic cardiomyopathy. Pace-mapping was performed at sites with low voltage. Radiofrequency energy was delivered at sites with concealed entrainment or matching pace-maps. Results : One hundred ninety-five VTs (mean cycle length 363 ± 88 ms) were induced. Sites with prespecified ablation criteria displaying IPs during sinus rhythm were recorded in 21 of 35 patients (60%, IP-positive). In these patients, a total of 216 sites meeting prespecified ablation criteria were identified and 146 of 216 sites (68%) displayed IPs. Fifteen of 21 IP-positive patients (71%) no longer had inducible VT after ablation. In 14 of 35 patients, no sites with IPs where prespecified ablation criteria were met were identified (IP-negative) despite combined endocardial and epicardial mapping in 7 of 14 patients. Only 1 of 14 IP-negative patients (7%) no longer had inducible VT at the end of the ablation procedure. During a mean follow-up of 18 ± 13 months, 14 of 21 IP-positive patients (67%) remained arrhythmia-free, compared to 1 of 14 IP-negative patients (7%; P < 0.01). Half of the IP-negative patients had major adverse events due to recurrent arrhythmias, compared to none in IP-positive patients. Conclusion : IPs in conjunction with pace-mapping are helpful for identifying critical isthmus areas for ablation of VT in patients with various types of nonischemic cardiomyopathy. Patients with nonischemic cardiomyopathy in whom the arrhythmogenic substrate is characterized by IPs have a more favorable outcome than patients in whom IPs are absent. J Cardiovasc Electrophysiol, Vol. 21, pp. 1017-1023, September 2010)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79253/1/j.1540-8167.2010.01756.x.pd

Allosteric Regulation of Na/Ca Exchange Current by Cytosolic Ca in Intact Cardiac Myocytes

The cardiac sarcolemmal Na-Ca exchanger (NCX) is allosterically regulated by [Ca]i such that when [Ca]i is low, NCX current (INCX) deactivates. In this study, we used membrane potential (Em) and INCX to control Ca entry into and Ca efflux from intact cardiac myocytes to investigate whether this allosteric regulation (Ca activation) occurs with [Ca]i in the physiological range. In the absence of Ca activation, the electrochemical effect of increasing [Ca]i would be to increase inward INCX (Ca efflux) and to decrease outward INCX. On the other hand, Ca activation would increase INCX in both directions. Thus, we attributed [Ca]i-dependent increases in outward INCX to allosteric regulation. Ca activation of INCX was observed in ferret myocytes but not in wild-type mouse myocytes, suggesting that Ca regulation of NCX may be species dependent. We also studied transgenic mouse myocytes overexpressing either normal canine NCX or this same canine NCX lacking Ca regulation (Δ680–685). Animals with the normal canine NCX transgene showed Ca activation, whereas animals with the mutant transgene did not, confirming the role of this region in the process. In native ferret cells and in mice with expressed canine NCX, allosteric regulation by Ca occurs under physiological conditions (KmCaAct = 125 ± 16 nM SEM ≈ resting [Ca]i). This, along with the observation that no delay was observed between measured [Ca]i and activation of INCX under our conditions, suggests that beat to beat changes in NCX function can occur in vivo. These changes in the INCX activation state may influence SR Ca load and resting [Ca]i, helping to fine tune Ca influx and efflux from cells under both normal and pathophysiological conditions. Our failure to observe Ca activation in mouse myocytes may be due to either the extent of Ca regulation or to a difference in KmCaAct from other species. Model predictions for Ca activation, on which our estimates of KmCaAct are based, confirm that Ca activation strongly influences outward INCX, explaining why it increases rather than declines with increasing [Ca]i

Multistep Ion Channel Remodeling and Lethal Arrhythmia Precede Heart Failure in a Mouse Model of Inherited Dilated Cardiomyopathy

Background: Patients with inherited dilated cardiomyopathy (DCM) frequently die with severe heart failure (HF) or die suddenly with arrhythmias, although these symptoms are not always observed at birth. It remains unclear how and when HF and arrhythmogenic changes develop in these DCM mutation carriers. In order to address this issue, properties of the myocardium and underlying gene expressions were studied using a knock-in mouse model of human inherited DCM caused by a deletion mutation DK210 in cardiac troponinT. Methodology/Principal Findings: By 1 month, DCM mice had already enlarged hearts, but showed no symptoms of HF and a much lower mortality than at 2 months or later. At around 2 months, some would die suddenly with no clear symptoms of HF, whereas at 3 months, many of the survivors showed evident symptoms of HF. In isolated left ventricular myocardium (LV) from 2 month-mice, spontaneous activity frequently occurred and action potential duration (APD) was prolonged. Transient outward (Ito) and ultrarapid delayed rectifier K + (IKur) currents were significantly reduced in DCM myocytes. Correspondingly, down-regulation of Kv4.2, Kv1.5 and KChIP2 was evident in mRNA and protein levels. In LVs at 3-months, more frequent spontaneous activity, greater prolongation of APD and further down-regulation in above K + channels were observed. At 1 month, in contrast, infrequent spontaneous activity and down-regulation of Kv4.2, but not Kv1.5 or KChIP2, were observed