Assessing the effect of breed, age, and sex on muscarinic receptor distribution in atria and ventricles of turkeys

Atrial and ventricular myocardium from young (6-wk-old), young adult (3-6-mo-old), and aged (14-15-mo-old) meat-type (B.U.T. Big 6) and wild-type (Cröllwitzer) turkeys were used to study the influence of age and sex on cholinergic muscarinic receptors using [3H]-N-methyl-scopolamine (3H-NMS) binding studies. In both breeds, saturation experiments indicated the presence of regional-, sex-, and age-related differences in the density of cholinergic muscarinic receptors (Bmax), that is, a decrease or increase. Except for right atria, Bmax was decreased in both male and female B.U.T. Big 6 hearts with increasing age. Similarly, a negative correlation between Bmax and age could be seen in female and male atria of Cröllwitzer turkeys, while positive correlation could be seen in right and left ventricles of male, and only right ventricles of female Cröllwitzer turkeys. The affinity of the receptor (KD) was not affected by age, sex and breed. In all cardiac chamber tissues, the M2-subtype was shown to be predominant followed by the M3-subtype and to a lesser extent the M1-subtype. Aspects of this age-dependent remodeling of the heart differ between sexes, resulting in maladaptive changes in older turkeys with a high degree of frailty. These observations may help explain why males and females are susceptible to different cardiovascular diseases as they age and why frail older adults are most often affected by these diseases.

Dimethyl sulfoxide favors the emetic efficacy of lycorine in beagle dogs - a novel strategy for the treatment of poisoning

Poisoning in small animals represents an ongoing hazard and therapeutic problem in veterinary medicine. Therapeutic induction of emesis in time enables a fast elimination of a toxic compound resulting in a shortened course of poisoning and a higher safety level thereafter, which decisively improves prognosis and treatment. Lycorine is a reliable emetic drug in beagle dogs without serious side effects thought to be more beneficial in tolerability and efficacy than the rarely used apomorphine. Therefore, this study investigates efficacy and tolerability of differently composed potential drug formulations of lycorine hydrochloride for s.c. administration in dogs as an emetic principle. By emesis response analysis four dimethyl sulfoxide (DMSO)-based active pharmaceutical ingredient (API) formulations were favored. Two of them (F5 and F6) qualified for further drug development. Both formulations ensure a safe pharmacologically induced emesis within about 30 min after injection, suitable for use as an in time decontaminant in acute poisoning of dogs. DMSO-based formulations were well tolerated and offer a novel promising strategy for treatment of poisoning.

The Rho kinase (ROCK) inhibitor Y-27632 reduces the β2-adrenoceptor density but enhance cAMP formation in primary equine bronchial epithelial cells

The present study addresses the effect of the Rho-kinase (ROCK) inhibitor Y-27632 on the β₂-adrenoceptor density and β-agonist-stimulated intracellular second messenger cAMP formation in primary equine bronchial epithelial cells (EBEC). Y-27632 significantly decreased the β₂-adrenoceptor number (B_max) without markedly affecting the receptor affinity (dissociation constant, K_D) to the radioligand [¹²⁵I]-iodocyanopindolol (ICYP). In contrast, Y-27632 augmented the β-agonist-stimulated intracellular cAMP production. Herein, Y-27632 markedly increased the maximal cAMP responses (E_max) (isoproterenol > epinephrine > norepinephrine) but did not shift the β-agonist concentration-effect curves to the left. The β₂-selective antagonist ICI 118.551 and the β_1/β₂-antagonsit propranolol but not the β₁-selctive antagonist CGP 20712A reversed the isoproterenol-induced cAMP formation equally in Y-27632-treated and control EBEC, suggesting the effect was merely related to the β₂-subtype. These results show that Y-27632 differentially regulates the receptor density and function. Thus, these findings provide the first evidence that the functional interaction of the β₂-adrenoceptor and Rho-kinase (ROCK) signaling pathways decreases the receptor expression but enhances receptor downstream cAMP formation. This differential regulation of the receptor density and function by Y-27632 should be further reconsidered with regard to the beneficial effect of the drug in asthma therapy.

Expression of muscarinic acetylcholine receptors in turkey cardiac chambers

The aim of the present study was to characterize the specific binding sites for [N-methyl-³H]-scopolamine ([³H]-NMS), a radioligand for labeling muscarinic acetylcholine receptors (mAChRs), in membranes of four heart chambers obtained from adult male British United Turkey (BUT) Big 6 ("meat-type") and Cröllwitzer ("wild-type") turkeys. MAChR subtypes were examined by inhibiting [³H]-NMS binding with subtype selective non-labelled receptor antagonists. In all left and right atria as well as left and right ventricles of both turkey breeds, the specific [³H]-NMS binding was saturable, reversible and of high affinity (K_D range: 0.5-1.0 nM). The maximum receptor density (B_max) was not significantly different between the four cardiac chambers of BUT Big 6 turkeys, but a significant difference was found between atria and ventricles of Cröllwitzer turkeys. Moreover, significant lower B_max was found in the atria of Cröllwitzer turkeys than in the atria of BUT Big 6, while the ventricular B_max was significantly higher. In all cardiac chambers, unlabeled mAChR antagonists competed for specific [³H]-NMS binding sites in a concentration-dependent manner, suggesting the presence of the M₃ and M₂ receptor subtypes, whereby the latter was the predominant subtype. The presence of the M₁ subtype could not be excluded. In conclusion, there was a difference between BUT Big 6 ("meat-type") and Cröllwitzer ("wild-type") turkeys with regard to receptor density in heart chambers with dominant M₂ and M₃ receptor subtypes.

Assessment of Plasma Zinc and Total Leukocyte Count in Calves Experimentally Infected with Mannheimia haemolytica

Mannheimia haemolytica is the main bacterial pathogen isolated in bovine respiratory disease (BRD), a common disease affecting calves before weaning. Previous research has shown that experimental infection with bovine herpesvirus 1, a respiratory virus, decreases plasma zinc (Zn) levels. However, changes in plasma Zn concentrations in calves experimentally infected with M. haemolytica have not been studied thus far. The objective of this study was to evaluate the effect of experimental infection with M. haemolytica on plasma Zn concentration in calves. Total leukocyte count and bovine respiratory disease (BRD) clinical score were also evaluated. We conducted a 6-day trial in 14 male Holstein calves randomly assigned to one of two groups, experimental (EG, n = 8) and control (CG, n = 6). Animals in EG were intrabronchially inoculated with M. haemolytica (6.5 × 10⁶ CFU/mL) on day 0 of the trial. Plasma Zn levels were affected by time, treatment, and time by treatment interaction, being lower in EG compared with CG on days 1, 2, and 3. Differences in total leukocyte count were significant on day 1, observing a tendency on day 3. BRD clinical score differed between groups, being higher in EG throughout the trial. We conclude that experimental M. haemolytica infection reduced plasma Zn concentration in clinically ill calves, suggesting that the clinical condition of animals (healthy/ill) should be considered to better interpret plasma Zn values.

Effects of Hypoxia and Acidosis on Cardiac Electrophysiology and Hemodynamics. Is NHE-Inhibition by Cariporide Still Advantageous?

Hypoxia often leads to severe cardiac malfunctions. It is assumed that intracellular calcium overload is -inter alia- responsible for left ventricular (LV) deterioration. Inhibition of the sodium-proton exchanger (NHE), which finally inhibits/slows calcium overload, may ameliorate cardiac function. Our aim was to evaluate cariporide, an inhibitor of NHE1 in a Langendorff-perfused heart model. To discriminate a potentially different impact of extracellular acidosis and hypoxia we examined 48 Chinchilla Bastard rabbits divided into 8 experimental groups: control group (pH = 7.4, O₂ = 100%) without or with cariporide (1 μM), acidosis group (pH = 7.0, O₂ = 100%) without or with cariporide (1 μM), hypoxia group (pH = 7.4, O₂ = 40%) without or with cariporide (1 μM) and hypoxia+acidosis group (pH = 7.0, O₂ = 40%) without or with cariporide (1 μM). Hearts were subjected to acidotic/hypoxic conditions for 90 min followed by 60 min of reperfusion. Hypoxia and hypoxia+acidosis led to a severe deterioration of LV function with a decrease in LV pressure by about 70% and an increase of end-diastolic pressure from 6.7 ± 0.6 to 36.8 ± 5.4 (hypoxia) or from 7.0 ± 0.2 to 18.6 ± 4.1 (hypoxia+acidosis). Moreover, maximum contraction velocity decreased from about 1,800 mmHg/s to 600 mmHg/s during hypoxia ± acidosis and maximum relaxation velocity deteriorated from −1,500 mmHg/s to about −600 mmHg/s. During reperfusion hearts subjected to hypoxia+acidosis recovered faster than hearts subjected to hypoxia alone, reaching control levels after 5 min of reperfusion. Electrophysiologic analysis revealed an 1.2 fold increase in both dispersion of activation-recovery interval and in total activation time in the hypoxia ± acidosis group. Cariporide application significantly improved LV hemodynamics and electrophysiology in the hypoxia group but not in the group subjected to hypoxia+acidosis. Immunohistologic analysis of cardiac specimen revealed a significant increase of factors involved in hypoxia/reperfusion injury like nitrotyrosine and poly-ADP-ribose as well as apoptosis-inducing factors like AIF or cleaved-caspase 3 in LV after hypoxia ± acidosis. ATP was reduced by hypoxia but not by acidosis. Again, cariporide mitigated these processes only in the hypoxia alone group, but not in the group with additional acidosis. Acidosis without hypoxia only marginally disturbed LV function and electrophysiology, and was not affected by cariporide. Thus, our study demonstrated that several detrimental effects of hypoxia were mitigated or abrogated by acidosis and that NHE-inhibition improved only hypoxia-induced cardiac dysfunction.

Presence and function of β-adrenergic receptors in primary equine bronchial epithelia cells

The β-adrenergic receptor (β-AR) plays an important role in regulating a variety of cell and organ functions in different animal species and is an important target in asthma pathogenesis and therapy. The β-AR expression and function in equine bronchial epithelial cells (EBEC) were not known but innervation and significant decrease in receptor level were reported in the equine bronchial tissues from asthmatic horses. ¹²⁵I-iodocyanopindolol (ICYP) binding studies were undertaken in primary freshly isolated and cultured EBEC to identify the presence of the β-ARs. The receptor distribution was assessed using subtype-selective β-AR antagonists (ICI 118 551 (β₂) and CGP 20712A (β₁). The β-AR function was confirmed by measuring the agonist-induced intracellular cAMP accumulation in freshly isolated and cultured EBEC. In both freshly isolated and cultured EBEC, the specific ICYP binding was saturable and of high affinity. The maximal receptor density (B_max) was 9763 ± 140 binding sites/cell (mean ± SEM, n = 7) and 10575 ± 194 binding sites/cell (mean ± SEM, n = 5) in freshly isolated and cultured EBEC, respectively. The receptor affinity to the ligand (K_D) was also not different between the two cell conditions. ICI 118.551 displaced ICYP with 25 000-fold higher affinity than CGP 20712A. Moreover, in both fresh isolated and cultured EBEC, cAMP-accumulation was stimulated with a rank-order of potency of isoproterenol > adrenaline > noradrenaline. These results highlight the β₂-AR to be a key subtype in both freshly isolated and cultured primary EBEC.

Statistical optimization of process parameters for improvement of phycobiliproteins (PBPs) yield using ultrasound-assisted extraction and its kinetic study

The present study is mainly concerned for the development of an optimal ultrasound-assisted extraction (UAE) condition for phycobiliproteins (PBPs) from Oscillatoria sp. (BTA 170) using Taguchi methodology. Four process parameters viz. solid to liquid ratio, duty cycle, electrical acoustic intensity, and pH, for UAE were optimized using Taguchi methodology for enhanced PBPs extraction. The ratio of signal to noise (S/N) was used to compute the optimized condition required to attain a higher yield of PBPs, the average performance of individual parameter and corresponding interactive effects. The statistically significant parameters with their contribution were assessed using Analysis of variance (ANOVA). Results showed that duty cycle contributed the maximum influence (30.81%) on phycocyanin (PC) extraction followed by a solid liquid ratio (28.62%), pH (22.46%) and electrical acoustic intensity (18.10%). The highest contribution on the extraction of phycoerythrin (PE) was found from pH (33.16%), followed by duty cycle (31.57%), solid to liquid ratio (22.83%) and electrical acoustic intensity (12.45%). For extraction of allophycocyanin (APC), the duty cycle, solid to liquid ratio, pH and electrical acoustic intensity contributed 29.47, 29.07, 29.03, and 12.43% respectively. Results obtained from Taguchi methodology indicated that enhanced PC (94.10%), PE (95.20%) and APC (90.54%) can be achieved with solid-liquid ratio (0.2 g/ml), electrical acoustic intensity (16.99 w/cm²), duty cycle (75%), and pH 7 than the yield of PBPs obtained under unoptimized condition. In the present study, higher yield of PC (38.99%), PE (20.84%), and APC (11.93%) were attained with UAE compared to yield obtained from homogenized Oscillatoria sp. BTA 170 using 0.05 M phosphate buffer. Batch extraction data of PBPs under UAE was fitted well with the second order model. The values of second-order rate constant (k) were computed as 6.66 × 10^-4, 64.09 × 10^-4 and 1.49 × 10^-4 L/mg/min for extraction of PC, PE and APC respectively. The PBPs exhibited significant antioxidant property and hydrogen peroxide scavenging activity, which were increased with the enhancement of PBPs concentration.

Equine bronchial fibroblasts enhance proliferation and differentiation of primary equine bronchial epithelial cells co-cultured under air-liquid interface

Interaction between epithelial cells and fibroblasts play a key role in wound repair and remodelling in the asthmatic airway epithelium. We present the establishment of a co-culture model using primary equine bronchial epithelial cells (EBECs) and equine bronchial fibroblasts (EBFs). EBFs at passage between 4 and 8 were seeded on the bottom of 24-well plates and treated with mitomycin C at 80% confluency. Then, freshly isolated (P0) or passaged (P1) EBECs were seeded on the upper surface of membrane inserts that had been placed inside the EBF-containing well plates and grown first under liquid-liquid interface (LLI) then under air-liquid interface (ALI) conditions to induce epithelial differentiation. Morphological, structural and functional markers were monitored in co-cultured P0 and P1 EBEC monolayers by phase-contrast microscopy, scanning and transmission electron microscopy, hematoxylin-eosin, immunocytochemistry as well as by measuring the transepithelial electrical resistance (TEER) and transepithelial transport of selected drugs. After about 15–20 days of co-culture at ALI, P₀ and P₁ EBEC monolayers showed pseudo-stratified architecture, presence of ciliated cells, typically honeycomb-like pattern of tight junction protein 1 (TJP1) expression, and intact selective barrier functions. Interestingly, some notable differences were observed in the behaviour of co-cultured EBECs (adhesion to culture support, growth rate, differentiation rate) as compared to our previously described EBEC mono-culture system, suggesting that cross-talk between epithelial cells and fibroblasts actually takes place in our current co-culture setup through paracrine signalling. The EBEC-EBF co-culture model described herein will offer the opportunity to investigate epithelial-mesenchymal cell interactions and underlying disease mechanisms in the equine airways, thereby leading to a better understanding of their relevance to pathophysiology and treatment of equine and human asthma.

Modulation of TNF-α, IL-1Ra and IFN-γ in equine whole blood culture by glucocorticoids

Glucocorticoids are important drugs in the treatment of many inflammatory, autoimmune and allergic diseases in humans and animals. We investigated the effects of hydrocortisone and dexamethasone on TNF-α, IL-1Ra and INF-γ release in stimulated whole blood cell culture from healthy horses. Whole blood cell cultures proved to be useful for the characterization of the anti-inflammatory properties of new drugs. Diluted equine whole blood was exposed to lipopolysaccharide (LPS) and PCPwL (a cocktail consisting of phythemagglutinin E, concanavalin A, pokeweed mitogen and lipopolysaccharide) in the presence or absence of hydrocortisone and dexamethasone (10^-12 - 10^-5 M). TNF-α and IL-1Ra (LPS) as well as IFN-γ (PCPwL) levels were measured in the supernatants using specific enzyme-linked immunosorbent assay (ELISA). The LPS-induced TNF-α and IL-1Ra as well as the PCPwL-induced IFN-γ levels were more potently suppressed by dexamethasone than by hydrocortisone in a concentration-dependent manner. Dexamethasone inhibited TNF-α, IL-1Ra and IFN-γ with the half maximal inhibition concentration (IC₅₀) values of 0.09 μM, 0.453 μM and 0.001 μM, respectively, whereas hydrocortisone inhibited these cytokines with lower IC₅₀ values of 1.45 μM, 2.96 μM and 0.09 μM, respectively. Our results suggest that the equine whole blood test system is useful and reliable to evaluate drug effects and immunological alterations and offers several advantages including simple and cheap performance in physiological and pathological conditions.

Effect of Isothermic Dialysis on Intradialytic Hypertension

The primary outcome was incidence of intradialytic hypertension (IDH) during standard and cooler isothermic dialysate temperatures. Two pair of haemodialysis sessions were done at 37°C (SHD) and at isothermic temperature (IHD). All the four dialysis were done on the same time of the day to negate the changes due to circadian variation in body temperature. Axillary and tympanic temperatures were measured before start of the dialysis and dialysis temperature was adjusted as per axillary temperature. Sixty patients were enrolled and completed the study. The mean delivered dialysate temperature in the intervention group was 36.5 ± 0.2 achieving a 0.5 ± 0.2°C between-group separation. The incidence of IDH and intradialytic hypotension while on SHD and IHD were 79/120 (66%) vs 44/120 (37%), odds ratio (OR) 3.3, 95% confidence interval (CI) (1.96–5.65) and 45/120 (38%) vs 14/120 (12%), OR 4.5, 95% CI (2.3–8.7), respectively. The 4 h time averaged mean systolic blood pressure (SBP) at IHD and SHD were 154 ± 1.7 and 157.2 ± 1.1 mmHg, respectively, the mean difference in SBP being −3.4 mmHg to −3.1 mmHg, 95% CI, P < 0.001. The standard deviation, a measure of BP variability was lower at IHD than at SHD (P < 0.001). In a subgroup analysis during IHD there was a significant reduction of both SBP and diastolic BP during the entire duration of dialysis in 35 out of 60 patients (systolic 4 h mean 154.96 ± 2.22 vs 164.32 ± 1.99 mmHg), (diastolic 4 h mean 79.24 ± 0.82 vs 82.54 ± 0.68 mmHg) – (rANOVA for systolic and diastolic <0.001). This phenomenon of cooler dialysis causing reduction of BP was reproduced in the same group of patients when the IHD was repeated another time (systolic 4 h mean 157.95 ± 1.88 vs 160.65 ± 1.47), (diastolic 4 h mean 79.27 ± 0.74 vs 82.03 ± 1.07) rANOVA for systolic and diastolic <0.001. The incidence of IDH can be reduced significantly by reducing the dialysate temperature to patients' body temperature. Hypertension during dialysis is related to heat gain during dialysis.

Pharmacokinetic evaluation of a transdermal anastrozole-in-adhesive formulation

Background and objective

Anastrozole is a well-established active pharmaceutical ingredient (API) used for the treatment of hormone-sensitive breast cancer (BC) in postmenopausal women. However, treatment with the only available oral formulation is often associated with concentration-dependent serious side effects such as hot flashes, fatigue, muscle and joint pain, nausea, diarrhea, headache, and others. In contrast, a sustained-release system for the local application of anastrozole should minimize these serious adverse drug reactions.

Methods

Anastrozole-in-adhesive transdermal drug delivery systems (TDDS) were developed offering efficient loading, avoidance of inhomogeneity or crystallization of the drug, the desired controlled release kinetics, storage stability, easy handling, mechanical stability, and sufficient stickiness on the skin. In vitro continuous anastrozole release profiles were studied in Franz diffusion cells. In vivo, consecutive drug plasma kinetics from the final anastrozole transdermal system was tested in beagle dogs. For drug analysis, a specific validated liquid chromatography– mass spectrometry method using fragment ion detection was developed and validated.

Results

After efficient drug loading, a linear and sustained 65% drug release from the TDDS over 48 h was obtained. In vivo data showed a favorable anastrozole plasma concentration–time course, avoiding side effect-associated peak concentrations as obtained after oral administration but matching therapeutic plasma levels up to 72 h.

Conclusion

These results provide the basis for establishing the transdermal application of anastrozole with improved pharmacokinetics and drug safety as novel therapeutic approach and promising option to treat human BC by decreasing the high burden of unwanted side effects.

Breed-related differences in age-dependent down-regulation of the β1-adrenoceptor and adenylate cyclase activity in atrial and ventricular myocardium of Cröllwitzer ("wild-type") turkeys

In conventional meat-type (British United Turkey (B.U.T.) Big 6) turkey hearts, it has been shown that all cardiac chambers exhibit down-regulation of the β1-adrenoceptors (β1-AR) and concomitantly cAMP accumulation with increasing age regardless of sex. In this study we proved the hypothesis that breed differences exist in age-dependent alterations in the β1-AR system. Right (RA) and left (LA) atrial as well as right (RV) and left (LV) ventricular tissues were collected from male and female Cröllwitzer "wild-type" turkey poults of increasing age (6 wk, 12 wk, 16 wk, 21 wk). The β1-AR density and function were quantified by (-)-[125I]-iodocyanopindolol (ICYP) radioligand binding analysis in cell membranes from 4 cardiac chambers. Basal and stimulated cAMP production was determined as indicator of the receptor function. Wild-type turkeys showed significantly higher heart to body weight ratio than the meat-type B.U.T. Big 6 turkeys. In both sexes of Cröllwitzer turkey hearts, the β1-AR density decreased with age but significance was reached in male cardiac chambers. The receptor affinity (KD) and subtype distribution were not altered. Sex had no effect on age-related decrease in receptor density but had an effect on adenylate cyclase (AC) activity and subsequently cAMP production. In male Cröllwitzer turkey hearts of all ages, cAMP remained at same level, whereas this was even increased in female cardiac chambers. Thus, breed affected age-related receptor-, G-protein and AC-stimulated cAMP formation in normal ventricles and atria, with females exhibiting pronounced increase with age. This suggests that the receptor signaling in wild-type turkey hearts is not as blunted as in hearts of meat-type turkey poults in which stressful farming conditions and fast growing lead to receptor down-regulation.

An Unusual Association of Renal Cell Carcinoma and Renal Malakoplakia with Focal Segmental Glomerulosclerosis in an Elderly Patient

The association of malignancy and glomerulonephritis may be missed, especially in elderly patients. Here, we report a case of eosinophilic variant of renal cell carcinoma and renal parenchymal malakoplakia discovered on renal biopsy in a patient with steroid-dependent nephrotic syndrome. The presence of malakoplakia in our biopsy was probably due to systemic steroid therapy for glomerulonephritis, presence of concomitant asymptomatic urinary tract infection, and/or history of diabetes mellitus. The patient had remission of proteinuria following laparoscopic removal of the tumor, indicating probable remission of glomerulonephritis.

Interpretation of Kidney Biopsy in Indian Patients Older than 60 Years: A Tertiary Care Experience

The adult population above the age of 60 years has significantly increased in India, with a life expectancy of 68.4 years in 2016. Data regarding the renal histopathology in these patients are scarce though the number of native kidney biopsies done in this subset of population is increasing. The present study is a retrospective analysis of 231 biopsies from a total of 700 biopsies, from patients above 60 years of age (M = 65.8%; F = 34.2%) with a mean age of 64 ± 6.03 years. The indications for kidney biopsy included nephrotic syndrome (NS) (30.4%), nephritic syndrome (19.1%), rapidly progressive renal failure (11.7%), acute kidney injury (AKI) (15.7%), and acute worsening of preexisting chronic kidney disease (CKD) (23%). The median percentage of glomerulosclerosis was 22% (5%–45%), and interstitial fibrosis and tubular atrophy was 30% (10%–50%). The most common cause for nephrotic syndrome was membranous nephropathy (31.4%) and for nephritic syndrome was benign arterionephrosclerosis (22.7%). Postinfectious glomerulonephritis (29.6%) was the leading cause for rapidly progressive renal failure. Acute injury on CKD was notable in patients with diabetic nephropathy (30.2%). The predominant causes for AKI were acute tubulointerstitial nephritis (33.3%), acute tubular necrosis (22.2%), and acute pyelonephritis (19.4%). The biopsy proven histopathological features enabled us in tailoring the therapy. None of the patients developed life-threatening complications following ultrasonography-guided biopsy.

Renal allograft eosinophilia: An unusual presentation of sudden graft dysfunction

We present a case of sudden allograft dysfunction 11 months after renal transplantation which presented as severe peripheral and allograft eosinophilia and was managed as a case of an acute cellular rejection with significant interstitial graft eosinophilic infiltration. Patient had partial response to antirejection therapy and eventually ended up in a chronic allograft dysfunction.

Influence of Mechanical Circulatory Support on Endothelin Receptor Expression in Human Left Ventricular Myocardium from Patients with Dilated Cardiomyopathy (DCM)

Background

In terminal failing hearts ventricular assist devices (VAD) are implanted as a bridge to transplantation. Endothelin receptor (ETR) antagonists are used for treatment of secondary pulmonary hypertension in VAD patients. However, the cardiac ETR regulation in human heart failure and during VAD support is incompletely understood.

Methods

In paired left ventricular samples of 12 dilated cardiomyopathy patients we investigated the density of endothelin A (ET_A) and B (ET_B) receptors before VAD implantation and after device removal. Left ventricular samples of 12 non-failing donor hearts served as control. Receptor quantification was performed by binding of [¹²⁵I]-ET-1 in the presence of nonselective and ET_A selective ETR ligands as competitors. Additionally, the ETR mRNA expression was analyzed using quantitative real-time-PCR.

Results

The mRNA of ET_A but not ET_B receptors was significantly elevated in heart failure, whereas total ETR density analyzed by radioligand binding was significantly reduced due to ET_B receptor down regulation. ET_A and ET_B receptor density showed poor correlation to mRNA data (spearman correlation factor: 0.43 and 0.31, respectively). VAD support had no significant impact on the density of both receptors and on mRNA expression of ET_A whereas ET_B mRNA increased during VAD. A meta-analysis reveals that the ET_A receptor regulation in human heart failure appears to depend on non-failing hearts.

Conclusions

In deteriorating hearts of patients suffering from dilated cardiomyopathy the ET_A receptor density is not changed whereas the ET_B receptor is down regulated. The mRNA and the proteins of ET_A and ET_B show a weak correlation. Non-failing hearts might influence the interpretation of ET_A receptor regulation. Mechanical unloading of the failing hearts has no impact on the myocardial ETR density.

The Effectiveness of Gaseous Formaldehyde Decontamination Assessed by Biological Monitoring

The results of seven years experience of the effectiveness of routine gaseous formaldehyde decontamination of rooms, filter canisters and biological safety cabinets at ambient temperature are reported. The effectiveness of each decontamination was monitored biologically by the inactivation of Bacillus stearothermophilus spores at five locations in rooms and biological safety cabinets and at two locations in filter canisters. A greater than 104 reduction in viability was achieved for each group of five spore tests in 92% of room decontaminations and each group of five spore tests in 81% of biological safety cabinet decontaminations, and a greater than 104.7 reduction for both spore tests in 83% of filter canister decontaminations. This long-term study of 2,308 routine formaldehyde decontaminations of varying spaces in practical situations demonstrates the reliability of the procedure. The results confirm that previously-described methods can be applied with confidence for routine decontaminations of laboratory facilities and equipment.

Handling of Large Experimental Animals Infected with a Risk Group 4 Virus

The safe experimental handling of animals infected with a new Risk Category 4 virus posed significant biosafety challenges. Novel approaches for restraining, handling and inoculating horses, cats and large fruit-eating bats with equine morbillivirus were developed. Equipment was designed to allow staff working in encapsulating suits access to all parts of a large animal room capable of accommodating seven horses individually. Procedures were developed for the safe handling, anesthesia and euthanasia of experimental animals and for the disposal of infected horse carcasses. Comprehensive staff training for this demanding work included safety consciousness, teamwork and training in first aid and emergency procedures.

Physiological and proteomic analysis of salinity tolerance of the halotolerant cyanobacterium Anabaena sp

The halotolerant cyanobacterium Anabaena sp was grown under NaCl concentration of 0, 170 and 515 mM and physiological and proteomic analysis was performed. At 515 mM NaCl the cyanobacterium showed reduced photosynthetic activities and significant increase in soluble sugar content, proline and SOD activity. On the other hand Anabaena sp grown at 170 mM NaCl showed optimal growth, photosynthetic activities and comparatively low soluble sugar content, proline accumulation and SOD activity. The intracellular Na(+) content of the cells increased both at 170 and 515 mM NaCl. In contrast, the K(+) content of the cyanobacterium Anabaena sp remained stable in response to growth at identical concentration of NaCl. While cells grown at 170 mM NaCl showed highest intracellular K(+)/Na(+) ratio, salinity level of 515 mM NaCl resulted in reduced ratio of K(+)/Na(+). Proteomic analysis revealed 50 salt-responsive proteins in the cyanobacterium Anabaena sp under salt treatment compared with control. Ten protein spots were subjected to MALDI-TOF-MS/MS analysis and the identified proteins are involved in photosynthesis, protein folding, cell organization and energy metabolism. Differential expression of proteins related to photosynthesis, energy metabolism was observed in Anabaena sp grown at 170 mM NaCl. At 170 mM NaCl increased expression of photosynthesis related proteins and effective osmotic adjustment through increased antioxidant enzymes and modulation of intracellular ions contributed to better salinity tolerance and optimal growth. On the contrary, increased intracellular Na(+) content coupled with down regulation of photosynthetic and energy related proteins resulted in reduced growth at 515 mM NaCl. Therefore reduced growth at 515 mM NaCl could be due to accumulation of Na(+) ions and requirement to maintain higher organic osmolytes and antioxidants which is energy intensive. The results thus show that the basis of salt tolerance is different when the halotolerant cyanobacterium Anabaena sp is grown under low and high salinity levels.

Release kinetics of tumor necrosis factor-α and interleukin-1 receptor antagonist in the equine whole blood

Background

Horses are much predisposed and susceptible to excessive and acute inflammatory responses that cause the recruitment and stimulation of polymorphnuclear granulocytes (PMN) together with peripheral blood mononuclear cells (PBMC) and the release of cytokines. The aim of the study is to develop easy, quick, cheap and reproducible methods for measuring tumor necrosis factor alpha (TNF-α) and interleukin-1 receptor antagonist (IL-1Ra) in the equine whole blood cultures ex-vivo time- and concentration-dependently.

Results

Horse whole blood diluted to 10, 20 and 50 % was stimulated with lipopolysaccharide (LPS), PCPwL (a combination of phytohemagglutinin E, concanavalin A and pokeweed mitogen) or equine recombinant TNF-α (erTNF-α). TNF-α and IL-1Ra were analyzed in culture supernatants, which were collected at different time points using specific enzyme-linked immunosorbent assays (ELISA). Both cytokines could be detected optimal in stimulated 20 % whole blood cultures. TNF-α and IL-1Ra releases were time-dependent but the kinetic was different between them. PCPwL-induced TNF-α and IL-1Ra release was enhanced continuously over 24–48 h, respectively. Similarly, LPS-stimulated TNF-α was at maximum at time points between 8–12 h and started to decrease thereafter, whereas IL-1Ra peaked later between 12–24 h and rather continued to accumulate over 48 h. The equine recombinant TNF-α could induce also the IL-1Ra release.

Conclusions

Our results demonstrate that similar to PCPwL, LPS stimulated TNF-α and IL-1Ra production time-dependently in whole blood cultures, suggesting the suitability of whole blood cultures to assess the release of a variety of cytokines in health and diseases of horse.

Differential regulation of the β-adrenoceptor density and cyclic AMP level with age and sex in turkey cardiac chambers

Decreased responses of the heart to β-adrenoceptor stimulation with aging have been shown to occur merely in selected heart chambers in relation to increased catecholamine levels. However, there are no systematic studies that investigate all cardiac chambers with regard to receptor density and cAMP (adenosine 3', 5'-cyclic monophosphate) responses. We used meat-type turkey poults (British United Turkey (B.U.T.) Big 6) with increasing age because their heart seems to decrease in weight in relation to body weight and they are often used as an animal model for heart failure. The receptor density and distribution were quantified by radioligand binding analysis using (-)-[(125)I]-iodocyanopindolol and β-adrenoceptor subtype-specific antagonists (ICI 118.551 and CGP 20712 A) in membranes of four cardiac chambers (right and left atria and ventricles) of 6-week-, 12-week-, 16/21-week-, and 57-week-old B.U.T. BIG 6 turkeys. Receptor function was determined by measuring basal and stimulated cAMP production. In both sexes, the β-adrenoceptor density decreased significantly in all chambers with age without altered β-adrenoceptor subtype distribution. The receptor affinity (KD) to the radioligand was similar in hearts of all age groups. β-adrenoceptor-(isoproterenol and guanosine 5'-triphosphate), G-protein-(NaF) and catalytic unit of adenylate cyclase (forskolin, Mn(2+)) mediated cAMP responses were not chamber-dependent. Indeed, the cAMP level was significantly lower in 57-week-old hearts than in 6-week-, 12-week-, 16/21-week-old hearts. These data suggest that with increasing age and body weight, the β-adrenoceptor signal transduction pathway was highly blunted in all cardiac chambers, occurring by decreased receptor density and cAMP responses.

[Investigations on the acute, carrageenan-induced inflammatory reaction and pharmacology of orally administered sodium salicylate in turkeys]

The complex mechanisms of acute inflammation have been subject to veterinary investigations since a long time. However, knowledge on the role of specific inflammatory mediators, as well as pharmacokinetics (PK) and -dynamics (PD) of non-steroidal anti-inflammatory drugs (NSAID) in birds is limited. The objective of this work therefore was to establish a modified tissue cage-model to investigate the acute, carrageenan-mediated inflammatory response, as well as plasma and exudate-kinetics and the antiphlogistic effect of orally administered sodium salicylate on the elicited inflammatory reaction in turkeys. Within the class Aves, comparable studies have so far only been published in chicken. Following bilateral subcutaneous implantation of carrageenan-treated synthetic sponges in the lateral thoracic region, sodium salicylate was administered orally at a dose of 50 mg/kg body weight (BW; therapy group) twice daily on three consecutive days, while a control group received drinking water as a placebo (n = 24 per group). Combined PK and PD of sodium salicylate were evaluated on the basis of salicylate- and prostaglandin (PG) E2-plasma- and -exudate-concentrations, exudate volumes, as well as leukocyte exudate counts. Sodium salicylate was readily absorbed from the gastrointestinal tract and accumulated in the inflammatory exudate. At 4, 6, and 10 h after first application, sodium salicylate significantly reduced PG E2-concentrations in the inflammatory exudate when compared to the control group, whereas leukocyte exudate counts increased over time in both study groups, unaffected by sodium salicylate The described modified tissue cage-model can be beneficial for further research on the pathophysiology of avian inflammatory processes and the investigation of the combined pharmacodynamics and -kinetics of drugs in birds of adequate size.

Perovskite-Ni composite: a potential route for management of radioactive metallic waste

Management of nickel - based radioactive metallic wastes is a difficult issue. To arrest the release of hazardous material to the environment it is proposed to develop perovskite coating for the metallic wastes. Polycrystalline BaCe0.8Y0.2O3-δ perovskite with orthorhombic structure has been synthesized by sol-gel route. Crystallographic analyses show, the perovskite belong to orthorhombic Pmcn space group at room temperature, and gets converted to orthorhombic Incn space group at 623K, cubic Pm3m space group (with a=4.434Å) at 1173K and again orthorhombic Pmcn space group at room temperature after cooling. Similar observations have been made from micro-Raman study as well. Microstructural studies of BaCe0.8Y0.2O3-δ-NiO/Ni composites showed absence of any reaction product at the interface. This suggests that both the components (i.e. perovskite and NiO/Ni) of the composite are compatible to each other. Interaction of BaCe0.8Y0.2O3-δ-NiO/Ni composites with simulated barium borosilicate waste glass melt also did not reveal any reaction product at the interfaces. Importantly, uranium from the waste glass melt was found to be partitioned within BaCe0.8Y0.2O3-δ perovskite structure. It is therefore concluded that BaCe0.8Y0.2O3-δ can be considered as a good coating material for management of radioactive Ni based metallic wastes.

Antimicrobial activity and identification of potential antimicrobial compounds from aquatic pteridophyte, Azolla microphylla Kaulf

Azolla microphylla Kaulf. is an aquatic nitrogen fixing pteridophyte commonly found in aquatic habitats including paddy fields. Methanolic extract of the fronds of A. microphylla was subjected to partial purification by solvent partitioning with diethyl ether and ethyl acetate followed by hydrolysis, and further partitioning with ethyl acetate. The two fractions, thus obtained were tested for antibacterial activity. It was observed that the ethyl acetate fraction inhibited the growth of the pathogenic bacterium Xanthomonas oryzae. The GC-MS analysis of the ethyl acetate fraction showed several prominent peaks with retention time ranging from 8.83 to 45.54 min. A comparison of these peaks with the GC-MS libraries revealed that it could be eicosenes and heptadecanes with potential of antimicrobial activity.

Mineral bone disease in maintenance hemodialysis patients: Association with morbidity and mortality

There is a paucity of data on mineral bone disease in maintenance hemodialysis (MHD) patients from India. This retrospective analysis was undertaken on 858 (males: 599; females: 259) patients from two medical centers on MHD from 1998 to 2010. Age, gender, months on dialysis, hours per session of dialysis, hemoglobin, serum calcium, inorganic phosphorus, intact parathyroid hormone (iPTH), urine output, erythropoietin dosage per week, blood sugar, blood pressure, urea reduction rate, gain in fluid and fluid removed per session, serum albumin, alkaline phosphatase, vitamin D level, supplemental vitamin D and use of phosphate binder for therapy were documented. Overall, 191 patients died (22%) during the observation period. There was an 86% patient survival rate at 1 year on dialysis and an overall predicted 3-year survival rate of 78%. A relatively higher iPTH (P = 0.012), a need for vitamin D supplementation (P = 0.003), less hours on dialysis per session (P = 0.046) and a non-vegetarian diet (P = 0.022) were significantly associated with mortality.