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Electrophysiologic properties of surviving Purkinje cardiomyocytes in the late postmyocardial-infarction phase are not well established. By using standard microelectrode techniques, we evaluated the effects of the class III agent d-sotalol on action potential parameters of single Purkinje cardiomyocytes isolated from normal canine hearts or those 10-14 days after infarction. Measurements were obtained at 2.5, 3.5, and 6 mMextracellular potassium concentrations. Action-potential parameters recorded at baseline did not differ significantly between normal and infarct-surviving Purkinje cardiomyocytes. At 3.5 and 6 mMextracellular potassium concentrations, surviving Purkinje cells appeared to be more sensitive to the effects of d-sotalol than normal Purkinje cells. In contrast, at 2.5 mMextracellular potassium concentration, the differential responses of normal and infarctsurviving Purkinje cells to d-sotalol was abolished. Reverse rate dependence was more prominent in normal than in postinfarction Purkinje cells, independent of the extracellular potassium concentration studied. The previously described enhanced sensitivity of subacutely infarcted tissue to class III agents seems to persist on a cellular level 10-14 days after myocardial infarction, even after full normalization of baseline action-potential parameters. Differential membrane-regulation mechanisms, dependent on the extracellular potassium concentrations, may account for the increased susceptibility to antiarrhythmia agents in the late postinfarction phase.

Carbon dioxide and ammonia concentrations were periodically examined between 1969 and 1973 in various cattle houses (dairy cows, new-born to six-month-old calves, and young and old beef cattle) in relation to the dung disposal systems.

ABSTRACTReoviruses were isolated in cell culture from a green iguana (Iguana iguana) and two chameleons (species unknown). The viruses were isolated on reptile and avian cells at 28°C (82°F) and caused the formation of syncytia. Using a recently described nested reverse transcriptase polymerase chain reaction assay targeting the RNA-dependent RNA polymerase gene of the genera Orthoreovirusand Aquareovirus, the isolates were partially characterized as orthoreoviruses closely related to orthoreoviruses from snakes. The clinical significance of the reovirus infections in the lizards was not always clear. This study is the first to provide sequence data from reoviruses isolated from lizards.

The glycoprotein fetuin-A has anti-inflammatory effects, increases insulin resistance and plays an important role in calcium metabolism. The aim of our study was to assess the predictive value of fetuin-A on atherosclerotic plaque progression in comparison to the established cardiovascular biomarker high sensitivity C-reactive protein (hsCRP).

Methods for the detection of pathogens associated with respiratory disease in reptiles, including viruses, bacteria, fungi, and parasites, are constantly evolving as is our understanding of the specific roles played by various pathogens in disease processes. Some are known to be primary pathogens with high prevalence in captive reptiles, e.g. serpentoviruses in pythons or mycoplasma in tortoises. Others are very commonly found in reptiles with respiratory disease but are most often considered secondary, e.g. gram negative bacteria. Detection methods as well as specific pathogens associated with upper and lower respiratory disease are discussed.