Effects of antihistamines,ebastine and terfenadine,on electrocardiogram in conscious dogs and cats

The purpose of this study was to evaluate the effects of ebastine and terfenadine on the electrocardiogram of conscious dogs and cats. In dogs, terfenadine at oral doses of 30 mg/kg twice a day for 7 days prolonged the electrocardiographic QT interval and the corrected QT (QTc) interval on the seventh day, whereas the drug did not affect these parameters on the first day. Plasma concentrations of terfenadine and its active metabolite, fexofenadine, reached 306 and 8,541 ng/mL, respectively, on the seventh day. Ebastine at oral doses of 30 and 100 mg/kg once a day for 7 days was without effect on the QT and QTc intervals, whereas the drug slightly shortened the RR interval. On the seventh day following the dose of 100 mg/kg, plasma concentrations of ebastine and its active metabolite, carebastine, reached 36 and 1,939 ng/mL, respectively. In conscious cats, terfenadine at oral doses of 30 mg/kg twice a day for 7 days prolonged the QT and QTc intervals, QRS duration, JT and the corrected JT intervals. Unexpectedly, terfenadine induced ventricular tachyarrhythmia and premature beats. On the other hand, ebastine at oral doses of 100 mg/kg once a day for 7 days was without effect on the electrocardiographic parameters in cats. These results suggest that the electrocardiographic changes indicative of the proarrhythmic potential of terfenadine can be evaluated in conscious dogs and especially in conscious cats by repeated oral administration, and that ebastine does not induce such changes. 58:209–217, 2003. © 2003 Wiley‐Liss, Inc.     

Serial changes in N-isopropyl-p[125I]-iodoamphetamine in mouse lung observed with a confocal laser scanning microscope

Serial changes in N-isopropyl-p[125I]-iodoamphetamine (125I-IMP) in mouse lungs were observed with a confocal laser scanning microscope. Male mice were intravenously injected with 125I-IMP and subjected to autoradiographic procedures 20 minutes, and 3 and 24 hours after injection. Differential interference contrast (DIC) images and confocal images were obtained with a confocal laser scanning microscope, and superimposed images were evaluated. Large numbers of silver grains were observed in the interstitium, bronchioles, and alveolar sacs 20 minutes after the injection, and lamellar distribution of the grains was observed on the ciliary surface. The numbers of silver grains in the interstitium and bronchioles had decreased 3 hours after the injection of 125I-IMP, but the numbers of silver grains in the alveolar spaces had not. Although small numbers of silver grains remained in both the bronchioles and alveolar sacs 24 hours after the injection, most of them had washed out. Confocal laser scanning microscopy is considered to be a useful procedure for studying the distribution of radioisotopes by microautoradiography, because it allows clear autoradiographs to be obtained in which tissues and silver grains are perfectly matched and all silver grains are in focus.     

Severe Sinus Bradycardia in Anorexia Nervosa-A Case Report

A case of anorexia nervosa complicated with severe sinus bradycardia and low T3 syndrome was reported.     

Cardiovascular changes in response to selective monoamine oxidase inhibition in the rat

Chronic (21 days) treatment with the selective monoamine oxidase (MAO)-A inhibitor clorgyline, but not with the MAO-B inhibitor deprenyl in pithed rats leads to increased blood pressure responses to sympathetic stimulation and intravenous tyramine, and to elevated unstimulated heart rates. No significant changes are observed in plasma catecholamine responses to sympathetic stimulation, nor in β-adrenoreceptor numbers in heart ventricles. These findings suggest that the hypotensive effects of MAO inhibitors result from central nervous system rather than peripheral nervous system alterations.     

MR imaging of the thyroid: correlation between apparent diffusion coefficient and thyroid gland scintigraphy

PURPOSE: To evaluate the usefulness of echo-planar MR imaging for assessing the thyroid function and confirm the clinical use of MR imaging for thyroid diseases. MATERIALS AND METHODS: Thirty-four patients with a variety of thyroid disorders (24 Graves disease; five subacute thyroiditis; five Hashimoto thyroiditis) were examined using T1-, T2-, and diffusion-weighted magnetic resonance (MR) imaging and thyroid scintigraphy with Tc-99m pertechnetate. RESULTS: The ADC values obtained from the diffusion-weighted images of the patients with Graves disease were significantly higher than those of patients with subacute hyroiditis and Hashimoto thyroiditis, though no difference among those disorders was observed on T1- and T2-weighted images. Based on the ADC value, anisotropy was not observed in the thyroid gland. An ADC value of 1.82 x 10(-3) mm(2)/second or higher indicated the presence of Graves disease (sensitivity 75%, specificity 80%). CONCLUSION: Diffusion-weighted MR images may be of value for the diagnosis of thyroid diseases and could be clinically important in the evaluation of thyroid function.     

Microvascular resistance in response to iodinated contrast media in normal and functionally impaired kidneys

Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m² (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = ?0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media.     

Clinical Significance of Fasting Serum Bile Acid in the Long-Term Observation of Chronic Liver Disease

Fasting serum bile acid (FSBA) was serially measured by a fluorescent enzyme method in a follow-up study of 61 patients with chronic liver disease. In chronic inactive hepatitis, fluctuation of FSBA was within the normal range in both the exacerbated state and in remission. In chronic active hepatitis, FSBA was abnormally elevated in both states, but the difference was not significant. In chronic active hepatitis where FSBA was elevated in the remission state above its value in the exacerbated state, exacerbation of the disease occurred repeatedly during the follow-up period. In compensated liver cirrhosis progressing into the decompensated form, FSBA levels increased before a decrease in the serum values of albumin, cholesterol, and cholinesterase, and an elevation of bilirubin. In liver cirrhosis, FSBA levels increased above 100 microM, 1-4 months before the appearance of ascites.     

Clinical effects of long-term administration of pimobendan in patients with moderate congestive heart failure

Summary The long-term efficacy of the positive inotropic and vasodilator drug, pimobendan, was assessed in 21 patients suffering from symptomatic heart failure. Patients were randomized to 16 weeks of double-blind therapy with either 2.5 or 5.0mg/day of pimobendan (n = 10), or a matching placebo (n = 11). Patients were blinded on the study drug if their clinical status had not substantially worsened during the study. Of the placebo-treated patients, 5 patients were withdrawn from the study because of a deterioration of their heart failure, while none of the active treated group was withdrawn because of increased symptoms. Quality of life, assessed by the specific activity scale derived from the metabolic costs of individual physical activity, was 3.45 ± 0.90 (SD) mets in the baseline state and increased significantly after week 16, averaging 5.07 ± 1.40 and 4.67 ± 1.47 mets at weeks 16 and 24, respectively. In the placebo-treated group, the specific activity scale was 3.27 ± 1.21 mets at the baseline and remained unchanged throughout the study period. Patients treated with pimobendan were able to significantly increase their exercise duration. The accompanying increase in peak oxygen uptake was statistically insignificant, due to the limited number of patients enrolled in the study. These results suggest that in contrast to the recent pessimistic view of the long-term efficacy of cardiotonic drugs, pimobendan is beneficial in treating patients with congestive heart failure and may favorably modify their prognosis. Further largescale evaluation of this agent is warranted.