Does closantel in therapeutic doses display thyroid hormone-like activity in sheep?

The aim of this study was to define the thyroid hormone-like activity of closantel in sheep by measuring some blood parameters that are known to be influenced by thyroid hormones triiodothyronine (T3) and thyroxine (T4). Our hypothesis was that, if closantel possesses thyroid hormone-like activity, its use under in vivo conditions will result in changes similar to those in hyperthyroidism. The study was conducted in 20 Jezersko-Solchava breed sheep. Blood sampling was performed before and 10 days after routine anthelmintic treatment with closantel. Complete blood count, plasma cholesterol, triglycerides, protein, and albumin levels, as well as those of serum T3 and T4, were compared before and 10 days after closantel administration. This routine anthelmintic treatment of sheep with closantel did not significantly influence hematological parameters, thyroid hormone levels, or most of the biochemical parameters. No evidence was found for thyroid hormone-like activity of closantel in sheep. However, significantly (P < 0.01) elevated levels of plasma triglycerides were present 10 days after closantel administration.

Lithium attenuates lipopolysaccharide-induced hypothermia in rats.

BACKGROUND: Changes in body temperature are common features among patients with sepsis and septic shock. Similarly, systemic administration of bacterial endotoxin (lipopolysaccharide, LPS) to rats leads to an initial hypothermia followed by elevation in body temperature. These changes in body temperature are accompanied by increased levels of prostaglandin E2 (PGE2) in the hypothalamus. OBJECTIVE: This study examined the effects of lithium and SB216763 - two different glycogen synthase kinase (GSK)-3 inhibitors - on LPS-induced changes in body temperature and hypothalamic PGE2 levels in endotoxemic rats. MATERIALS AND METHODS: Endotoxemia was induced by intraperitoneal injection of LPS (10 mg/kg). Lithium (100 mg/kg) and SB216763 (5 mg/kg) were administered at 2 h before LPS. Body temperature and mortality were monitored during 48 h after LPS injection. In another protocol, rats were sacrificed at 2 h post LPS injection and then, blood, liver and hypothalamus were extracted for inflammatory mediators determination. RESULTS: Lithium but not SB216763 significantly reduced LPS-induced hypothermia, while both compounds did not alter the subsequent elevation in body temperature. Moreover, only lithium significantly reduced hypothalamic PGE2 levels. On the other hand, both compounds significantly reduced plasma, hepatic and hypothalamic tumor necrosis factor-α and decreased plasma PGE2 levels. Both compounds did not alter LPS-induced mortality. CONCLUSIONS: These results suggest that the attenuation of LPS-induced hypothermia by lithium may derive from its reduction of hypothalamic PGE2 levels.

Effects of season, age, and breed on semen characteristics in different Bos taurus breeds in a 31-year retrospective study.

Besides genetic factors, the season of semen collection could have an important effect on ejaculate characteristics, although results from previously published studies are somewhat variable. To determine seasonal effects on semen characteristics, we have analyzed 71,983 ejaculates collected from bulls of four different breeds over a 31-year period. Ejaculate volume, semen concentration, and total sperm output were analyzed with the respect to season and age of bull. Results revealed that semen concentration did not vary significantly during seasons, and ejaculate volume and total sperm output are influenced by season in all breeds. The highest ejaculate volume and total number of sperm in ejaculates were observed during the summer, followed by spring, autumn, and winter. Results suggest that the gradual increase in the day length in the spring is most likely responsible for the highest sperm output during the summer months, suggesting that seasonal effects are also present in cattle, which is not normally considered a seasonal species.

Plasma pharmacokinetics of abamectin in fallow deer (Cervus dama dama) following subcutaneous administration.

The pharmacokinetics of abamectin (ABM) following a single subcutaneous administration of 200 µg/kg was evaluated in adult fallow deer by following ABM concentration in blood plasma. A nonlinear mixed effects modelling procedure was used for pharmacokinetic analysis. The time course of ABM concentration was described by a two-compartment model with first-order absorption. Abamectin absorption in fallow deer was rapid with a peak plasma concentration of 120.7 ± 33.2 ng/mL observed at 19.1 ± 7.7 h (mean ± SD). Half-lives of the distribution and terminal phase were 17.2 and 119.3 h, respectively. Typical apparent clearance of the bioavailable fraction (CL/F) was 0.795 L/h and was independent of animal weight. Considering the obtained pharmacokinetic parameters in our study, we may assume that effective parasite control in fallow deer is obtained using the usual recommended dose of 200 µg/kg.

Swallowing-induced atrial tachyarrhythmia triggered by salbutamol: case report and review of the literature.

CASE: A 49-year-old patient experienced chest discomfort while swallowing. On electrocardiogram, episodes of atrial tachyarrhythmia were recorded immediately after swallowing; 24-hour Holter monitoring recorded several events. The arrhythmia resolved after therapy with atenolol, but recurred a year later. The patient noticed that before these episodes he had been using an inhalator of salbutamol. After stopping the beta-agonist, and after a week with the atenolol, the arrhythmia disappeared. DISCUSSION: Swallowing-induced atrial tachyarrhythmia (SIAT) is a rare phenomenon. Fewer than 50 cases of SIAT have been described in the literature. This article summarizes all the cases published, creating a comprehensive review of the current knowledge and approach to SIAT. It discusses demographics, clinical characteristics and types of arrhythmia, postulated mechanisms of SIAT, and different treatment possibilities such as medications, surgery, and radiofrequency catheter ablation (RFCA). CONCLUSION: Salbutamol is presented here as a possible trigger for SIAT. Although it is difficult to define causality in a case report, it is logical to think that a beta-agonist like salbutamol (known to induce tachycardia) may be the trigger of adrenergic reflexes originating in the esophagus while swallowing and that a beta-blocker such as atenolol (that blocks the adrenergic activity) may relieve it.

Conservative management of implantable cardioverter defibrillator-related endocarditis due to Bacillus spp.

Endocarditis is a devastating complication of implantable cardioverter-defibrillator (ICD) therapy. Partial or complete device removal has been advocated for the treatment of this condition although controlled data are lacking. We present a case of ICD-related endocarditis caused by Bacillus spp. that occurred following coronary angiography. To the best of our knowledge, Bacillus spp. has not been previously described in such context. Moreover, conservative treatment with device retention was successful (no recurrence during a 6-year follow-up). Conservative management may be attempted in selected cases of ICD-related endocarditis, especially, those involving low-virulence organisms and rapid response to antibiotic therapy. This case also suggests that coronary angiography may be associated with transient bacteremia and subsequent infection of indwelling cardiac devices.

ST elevation in the anterior precordial leads during right ventricular infarction: lessons learned during primary coronary angioplasty--a case report.

ST elevation in the anterior leads may be due to isolated right ventricular infarction associated with occlusion of a nondominant or codominant right coronary artery. The authors report a case of isolated right ventricular infarction from a dominant right coronary artery's proximal occlusion in the presence of collateral circulation provided by the left coronary artery. Extensive damage occurred owing to compromise of the collateral circulation during primary coronary angioplasty. This is an unusual angiographic pattern for isolated right ventricular infarction. The potential consequences of percutaneous interventions to collateral vessels is discussed.

Low-pressure deployment of stents: short- and long-term outcome.

This study investigates a strategy of low-pressure stenting with concomitant anti-platelet treatment designed to prevent short- and long-term events after stenting. Ninety consecutive patients who underwent percutaneous transluminal coronary angioplasty with stenting using low-pressure stent deployment (mean 8.1 atmospheres) with concomitant anti-platelet therapy based on ticlopidine and aspirin were followed. The 30-day outcome revealed a stent thrombosis rate of 6.4%, while the 9-month major clinical event rate was 8.6%. Low-pressure stent deployment appears to confer added risk for acute or sub-acute thrombosis even when aspirin and ticlopidine are used. Conversely, low-pressure inflation is associated with excellent long-term results.

Serum T3 and T4 concentrations in the adult rats treated with herbicide 2,4-dichlorophenoxyacetic acid.

The influence of sublethal doses of 2,4-dichlorophenoxyacetic acid (2,4-D) on serum T3 and T4 concentrations in Hsd Cpb: Wistar rats of both sexes was studied. The trial was performed on 24 males and females respectively, each divided into three groups of 8 animals (control, groups 1 and 2). Aqueous solution of the compound (11 mg/kg body weight--group 1 and 110 mg/kg body weight--group 2) or clean tap water (control group) was used. Aliquots of 2.4 ml/kg body weight were administered with a stomach tube from the 1st to 10th day of the experiment. Three days before the first treatment and on the 6th and 13th day of the experiment the serum T3 and T4 concentrations were determined by commercial radioimmunoassay kits (Byk-Sangtec Diagnostica), validated for rats. A significant decrease of serum T4 (P < 0.01) and T3 (P < 0.001) was determined in males of groups 1 and 2 during the experiment. On the 6th day of experiment serum T4 and T3 values were significantly lower (P < 0.001 and 0.01 respectively) in group 2 than in the controls and group 1 of both males and females. During the whole experiment serum T4 levels were lower in females than in males (P < 0.05).

Is it safe to administer thrombolytic therapy to myocardial infarction patients soon after laparoscopic cholecystectomy?

Thrombolytic therapy is usually contraindicated after abdominal surgery because of the risk of bleeding. We report a case of a 73-year-old woman who was admitted because of anterior wall acute myocardial infarction (AMI) two weeks after laparoscopic cholecystectomy. She was treated with streptokinase, aspirin and heparin and subsequently developed a hematoma at the site of the removed gallbladder. Our observation suggests that thrombolytic therapy for anterior AMI, two weeks after laparoscopic cholecystectomy, should be considered as a relative contraindication and an optional treatment in this life-threatening situation.