Effect of supplemental dietary leucine and immune system stimulation on whole-body nitrogen utilization in starter pigs.

The increase in circulating pro-inflammatory cytokines following an immune challenge (e.g., with bacterial lipopolysaccharide [LPS]) causes a disruption in normal AA metabolism and increases visceral protein synthesis at the expense of muscle protein synthesis. The objective of this study was to determine the effect of supplemental dietary Leu on the dynamics of whole body nitrogen (N) retention in starter pigs before and after immune system stimulation (ISS) induced by LPS. A total of 28 starter pigs (14.46 ± 0.73 kg BW) were assigned to isoenergetic and isonitrogenous diets formulated to supply essential AA 10% above estimated requirements for maximum whole-body protein deposition (PD) and to contain increasing amounts of Leu: CON (1.36% SID Leu); LEU-M (2.04% SID Leu); and LEU-H (2.72% SID Leu). Pigs were housed in metabolic crates, scale-fed every 4 h based on BW, and adjusted to dietary treatments for 5 d. The 108-h N-balance experiment was divided into two periods: prechallenge (before LPS challenge; six 12-h collections) and challenge (after LPS challenge; three 12-h collections) periods. In both periods, blood was collected to determine plasma AA and urea N concentrations. At the start of the challenge period, one-half of the pigs fed CON and all pigs fed LEU-M and LEU-H were challenged with LPS (ISS+; 30 µg/kg injected intramuscularly); the remaining pigs fed CON were injected with saline (ISS-). Whole-body N retention was determined during subsequent 12-h collections. Plasma free Leu concentration increased linearly with increasing Leu content in the diet before LPS was administered (CON, 124 µmol/L; LEU-M, 185 µmol/L; LEU-H, 227 µmol/L; < 0.01). During the prechallenge period, N retention was lower in pigs fed LEU-M ( < 0.01) and there was no difference between pigs fed CON and LEU-H (7.91, 7.18, and 7.71 g/12 h for CON, LEU-M, and LEU-H, respectively). During the challenge period, N retention in pigs fed CON was higher in ISS- than ISS+ (5.37 vs. 3.83 g/12 h; < 0.01) but was not affected by diet in ISS+ pigs (3.83, 3.21, and 3.45 g/12 h for CON, LEU-M, and LEU-H, respectively; > 0.10). In healthy pigs, feeding a high excess of dietary Leu induced an anabolic response to compensate for reduced N retention that occurred in pigs fed an intermediate excess of dietary Leu. There was no effect of supplemental Leu on N retention in pigs after an LPS challenge.

Doppler evaluation of prosthetic mitral valves.

For the evaluation of patients with prosthetic heart valves Doppler echocardiography is superior over other noninvasive techniques because it allows quantitative assessment of valve function. As a noninvasive method Doppler is safe, easily repeatable and provides haemodynamic data that closely correlate with parameters obtained by invasive procedures (Sagar et al., 1986: Simpson et al., 1986; Wilkins et al., 1986; Gibbs, 1987). The purpose of our study was to evaluate Doppler characteristics of mechanical and tissue mitral prostheses; Starr-Edwards, Björk-Shiley, Hall-Medtronic and Hancock in patients with clinically normal valve function.

[Factors contributing to the onset of heart rupture in acute infarct]. / Faktori koji pridonose nastanku rupture srca u akutnom infarktu.

The aim of this study was to find out the contributing factors for cardiac rupture in the course of acute myocardial infarction (AMI). Past medical histories and autopsy data of 80 patients were analyzed. The first group consisted of 30 patients who died due to heart rupture in the course of AMI and the control group of 50 patients who died from the other, more common complications of AMI. There was no difference between the groups according to age and sex of the patients. All patients who died from the rupture of the heart had a history of heavy chest pain, while it was lacking in 30% of the patients of the control group (p less than 0.01). All the first group patients showed electrocardiograms diagnostic for AMI, while it was lacking in 14% of the second group patients (p less than 0.05). Almost a half of the second group patients (47%) were in the class I of the Killip's classification, while only 20% of the control group did not developed left ventricular failure. Pathological study showed that the rupture of the heart most commonly occurred in the course of an anterior myocardial infarction. There was no difference according to the size of infarctions between observed groups, but the thickness of the left ventricular wall was significantly less (p less than 0.05) in the control group, and the heart weights were higher (p less than 0.05) in the control group. There was advanced atherosclerosis of the coronary arteries and about two thirds of the first group patients showed acute coronary thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of nursery feeding program on subsequent growth performance, carcass quality, meat quality, and physical and chemical body composition of growing-finishing pigs.

An experiment was conducted to examine the effect of the nursery feeding program on subsequent growth performance, carcass quality, meat quality, and physical and chemical body composition of growing-finishing pigs. Four dietary treatments were used in a 2 × 2 factorial arrangement of treatments based on diet complexity (Complex vs. Simple) and in-feed antibiotics (2,730 [+AB] vs. 0 [-AB] mg of chlortetracycline /kg].A total of 552 pigs, in 5 blocks, were weaned at 21 ± 2 d of age with an initial BW of 7.03 ± 0.07 kg. Each experimental block had 3 pens per treatment, with 8 pigs per pen in blocks 1 and 2, and 10 pigs per pen in the remaining 3 blocks. Nursery diets were fed in a 3-phase feeding program (Phase I, II, and III diets fed for 1, 2, and 3 wk, respectively). All pigs were fed common grower-finisher diets thereafter. Six pigs per treatment were slaughtered for chemical body composition analysis at wk 2, 8, 12, and 17 postweaning. An additional 11 pigs per treatment were slaughtered at wk 17 postweaning (approximately 115 kg BW or market weight) for analysis of carcass characteristics, chemical and physical body composition, and meat quality. During the nursery phase, ADG was lower (P < 0.05) for pigs fed the Simple diet than those fed the Complex diet (491 vs. 528 g/d). Antibiotic usage improved (P < 0.05) ADG in Phases II (408 vs. 438 g/d) and III (689 vs. 720 g/d). In Phase I and II, G:F was lower (P < 0.05) for pigs fed the Simple diet than those fed the Complex diet (0.46 vs. 0.58 and 0.75 vs. 0.78 in Phases I and II, respectively). During the grower phase, pigs previously fed -AB diets grew faster than pigs fed +AB diets (P < 0.05; 1,009 vs. 971 g/d). There were no treatment effects on overall ADG or G:F from weaning to finishing. Nursery feeding program did not affect carcass quality characteristics. However, pigs previously fed +AB diets tended (P = 0.07) to have increased LM depth. Nursery feeding program had no effect on objective or subjective meat quality measures, chemical body composition, or the weight of primal and retail carcass cuts at wk 17 postweaning, with the exception of primal belly weight. These results indicate that feeding simple nursery diets, or nursery diets without antibiotics, compromises growth performance during the nursery period but does not affect overall growth performance between weaning and market BW, carcass characteristics, and meat quality. Thus, feed costs for nursery pigs can be reduced by feeding simple diets without compromising market BW and carcass and meat quality.

Can prazosin be used in the treatment of refractory heart failure only on the basis of clinical monitoring?

25 patients are presented with chronic cardiomyopathy (NYHA class IV), who were refractory to conventional digitalis and diuretics treatment which was administered over at least 3 weeks. The patients were split in 2 groups: the first group consisted of 10 patients who were haemodynamically monitored while being administered nitroprusside for 24 hours. After the treatment, the cardiac index significantly increased (by 36%), left ventricular filling pressure decreased (by 48%), and systemic vascular resistance fell (by 47%). The second group, consisting of 15 patients, was administered prazosin in addition to conventional treatment. The effects of prazosin were clinically monitored. After 3 weeks of continual prazosin treatment, the clinical condition of 12 patients was improved to NYHA class II whereas the condition of the other 3 was improved only to NYHA class III. During further treatment this improvement was maintained. The effects of the treatment can be easily followed and assessed on the basis of clinical features, so that other, more complex methods of follow-up are not required. The results of our study show that patients with refractory heart failure can be safely administered prazosin without previous assessment of haemodynamic parameters.

Effects of fluorocarbon propellants on respiratory flow and ECG.

Ten subjects were exposed to the propellants freon 11, freon 12, freon 114, to two mixtures of freon 11 and 12 and to a mixture of freon 12 and 114. The length of exposure was 15, 45 or 60 seconds. Maximum expiratory flow-volume (MEF) curves and ECG were recorded before, and intermittently up to 1 hour after, exposure. Breathing level concentrations of propellants during exposure were determined by gas chromatography. All freons induced biphasic reduction of ventilatory capacity on inhalation. The first fall occurred within a few minutes of exposure while the second was delayed 13-30 minutes after exposure. The effects of mixtures were greater than those of individual freons. The relative fall in MEF 75% was more pronounced than that in MEF 50%. No clear-cut pathological changes in ECG were found. Nevertheless, most subjects developed variations in heart rate exceeding those noted before exposure. In a few cases inversion of the T wave, and in one case atrioventricular block, were observed.

Daily administration of furosemide in dilated cardiomyopathy--yes or no?

Seventeen patients with dilated cardiomyopathy (mean ejection fraction 22%) in the NYHA state III or IV were investigated. All patients fulfilled the criteria of an indication for administration of furosemide, since left ventricular filling pressure (LVFP, measured as pulmonary capillary pressure) was 20 or more mm Hg in all. This study investigates the effects of an acute (40 mg i.v.) administration of furosemide (observation period 0 to 90 minutes after administration). Conventional M-mode, 2-dimensional and Doppler-echocardiography was performed in all patients. Patients were divided into 2 groups according to the degree of (relative) mitral regurgitation (MR): group 1 with moderate to severe (n = 10) and group 2 with mild or no MR (n = 7), 90 minutes after administration of furosemide LVFP decreased by 76%. In group 1 this occurred together with a 23% rise of cardiac index and a fall of systemic vascular resistance of 21%. In group 2 cardiac index decreased by 22% with a rise of systemic vascular resistance of 14%. The chronic oral administration of furosemide over 4 weeks ameliorated the NYHA state of all patients by one grade. We conclude from our results that patients with advanced dilated cardiomyopathy profit only from acute administration of furosemide if a significant (relative) MR is present also. A low dose chronic oral administration of the drug, however, leads in any case to clinical amelioration.

[Advantages and hazards of the intraoperative control of endocardial electrode pacemakers]. / Prednosti i opasnosti intraoperativne kontrole polozaja endokardne elektrode pacemakera.

Discussed in this study are the authors' experiences with electrostimulation of the heart. The study is based on 276 pacemaker operations performed in the past 7 years. The authors remain partial to the transvenously introduced endocardial pacemakers monitored by X-raj. When radiation symptoms manifested themselves in 2 team members, a revision was made in the procedure. As a result, the means by which one may be exposed to uncontrolled and, prolenged stron radiotion were cited. Such radiation can result in pathologic changes in the blood, damage to the skin, nails, germinative epithelium and bone marrow. To prevent such an outcome, certain precautionary measures are taken which protect both the patient and surgical team. Also mentioned is that the surgical personnel should have the same benefits as radiologists.