Myoglobin in myocardial infarction. Results in a coronary-care-unit population.

The purpose of this study was to define the performance characteristics of serum myoglobin determinations in the diagnosis of acute myocardial infarction (MI). Subjects of the study were 118 patients admitted consecutively to the coronary care unit. Daily measurements of serum myoglobin (by radioimmunoassay) were performed. For patients admitted within 24 hours of the onset of symptoms, a serum myoglobin level of 75 ng/ml had a diagnostic sensitivity of 91% and a specificity of 85%. In the same group of patients, the presence of the myocardial isoenzyme of creatine phosphokinase (CK-MB) showed a sensitivity of 94% and a specificity of 89%. Among the 32 patients with MI, the elevation of myoglobin preceded the appearance of CK-MB in 12 (38%), was concomitant with CK-MB appearance in 15 (47%), and followed CK-MB in none. Given the spectrum of patients in this coronary care unit, the addition of the myoglobin assay to the heart profile has increased its sensitivity for the diagnosis of MI. The assay materials are available in kit form, and the test can be performed in the routine radioimmunoassay laboratory. The results are available for reporting four to five hours after venipuncture.

Influence of carbohydrate on cytokine and phagocytic responses to 2 h of rowing.

PURPOSE: This study examined the influence of carbohydrate (C) versus placebo (P) beverage ingestion on the phagocytic and cytokine responses to normal rowing training by 15 elite female rowers. METHODS: Athletes received C or P before, during and after, two, 2-h bouts of rowing performed on consecutive days. Blood was collected before and 5-10 min and 1.5 h after rowing. Metabolic measures indicated that training was performed at moderate intensities, with some high-intensity intervals interspersed throughout the sessions. RESULTS: Concentrations of blood neutrophils and monocytes, phagocytic activity, and plasma IL-1ra were significantly lower postexercise after C versus P ingestion. No differences were observed for oxidative burst activity, IL-6, IL-8, or TNFalpha. Glucose was significantly higher after 2 h of rowing with C ingestion; however, cortisol, growth hormone, epinephrine, norepinephrine, and CRP were not affected by carbohydrate. CONCLUSIONS: These data indicate that carbohydrate compared with placebo ingestion attenuated the moderate rise in blood neutrophils, monocytes, phagocytosis, and plasma IL-1ra concentrations that followed 2-h bouts of training in elite female rowers. No changes in blood hormone concentrations were found.

Intracoronary myocardial perfusion imaging: patterns in patients with coronary artery disease.

Myocardial imaging following the intracoronary injection of radiolabeled particles is used to identify transmural scars in patients being evaluated for coronary atherosclerosis. Selective imaging of the microcirculation derived from each major coronary vessel is accomplished using a dual radionuclide technique. This report illustrates the various normal and abnormal imaging patterns encountered in patients with coronary artery disease. The regional myocardial nomenclature proposed by the American Heart Association Council on Cardiovascular Surgery is used. Correlation of the nuclear study with the contrast arteriogram and ventriculogram is essential for identifying both transmural scars and regions of collateral circulation. The procedure is safe and can be performed during routine coronary angiography.

Mechanism of electrical alternans in patients with pericardial effusion.

Electrical alternans concomitant with pericardial effusion has been considered a pathognomonic sign suggestive of a large effusion with cardiac tamponade, particularly if there is P wave alternans as well as QRS alternans. However, the mechanism of this phenomonon remains controversial. A patient with pericardial effusion secondary to adenocarcinoma of the lung with metastases, pericardial effusion, electrical alternans, and cardiac tamponade was studied by echocardiography, right and left heart catheterization, and pericardiocentesis. Hemodynamic data were consistent with cadiac tamponade. The echocardiogram demonstrated a large anterior and posterior pericardial effusion. Noncongruous motion of the septum and posterior wall was pericardial effusion. Noncongruous motion of the septum and posterior wall was recorded at a rate equal to the heart rate. In addition, congruous motion of the septum and posterior wall was recorded at a rate that was half the heart rate and corresponded to the electrical alternans. The congruous movement disappeared after pericardiocentesis, as did the electrical alternans. The electrical alternans is synchronous with and due to the pendulous movement of the heart within the pericardial sac, as demonstrated by echocardiogram and cineangiograms.

Immune function in female elite rowers and non-athletes.

OBJECTIVE: To compare immune function in female rowers and controls in the resting state, and then correlate the results with a two month history of upper respiratory tract infection (URTI). METHODS: Subjects included 20 elite female rowers located at the ARCO Olympic Training Centre in Chula Vista, California, and 19 non-athletic female controls. These two groups were compared cross sectionally for immune function and infection rates. RESULTS: Granulocyte/monocyte phagocytosis, oxidative burst activity, and plasma cytokine concentrations (interleukin-6, tumour necrosis factor-alpha, and interleukin-1 receptor antagonist) did not differ significantly between groups. Phytohaemagglutinin induced lymphocyte proliferative response (adjusted whole blood method) was significantly higher (31% and 36% for optimal and suboptimal concentrations respectively) in rowers than in controls. Natural killer cell activity was substantially higher (1.6-fold for total lytic units) in the female rowers than in controls. Two month health logs disclosed 5.2 (1.2) and 3.3 (1.1) days with URTI symptoms for the rowers and controls respectively (p = 0.268). For all 39 subjects combined, and for the 20 rowers separately, none of the immune parameters correlated significantly with number of days with URTI symptoms. CONCLUSIONS: In this cross sectional comparison of elite female rowers and non-athletes, a group difference was found for natural killer cell activity and phytohaemagglutinin induced proliferative response (whole blood technique), but not other measures of immune function. The number of days with URTI symptoms during the spring season did not differ between groups, and variations in blood measures of immunity were unrelated to URTI.

Immune response to two hours of rowing in elite female rowers.

The influence of carbohydrate (C) versus placebo (P) beverage consumption on the immune and hormonal responses to normal rowing training sessions was measured in 15 elite female rowers residing at the U.S. Olympic Training Center. In a randomized, counterbalanced design, the athletes received C or P beverages (double-blind) before, during, and after two 2-hour bouts of rowing (one day apart). Blood samples were collected before, and 5-10 minutes and 1.5 hours after rowing. Metabolic measures indicated that training was performed at moderate intensities, with some high intensity intervals interspersed throughout the sessions (mean oxygen uptake of 2,307+/-169 m x min(-1), 57% of VO2max). Glucose and insulin were significantly lower after two hours of rowing with ingestion of P compared to C. The patterns of change in cortisol, growth hormone, epinephrine, and norepinephrine did not differ between C and P rowing trials. Blood neutrophil cell counts and the neutrophililymphocyte ratio were significantly higher following P versus C rowing sessions. The patterns of change in blood lymphocyte and lymphocyte subset counts, and lymphocyte proliferative responses did not differ between P and C trials, except for a slight difference in NK cell counts and activity. In summary, minimal changes in blood hormonal and immune measures were found following two-hour bouts of training in elite female rowers. Carbohydrate compared to placebo ingestion attenuated the moderate rise in blood neutrophil counts, but had slight or no effects on other immune parameters.

Factors associated with mortality in feedlot cattle: the Bruce County Beef Cattle Project.

The design of and the analysis of data from the Bruch County Beef Cattle Project, particularity the field study, are presented and discussed. A major value of the study may lie in its ability to relate laboratory findings to events in the field. The factor most strongly related to mortality was ration, with cattle on hay based rations having a much lower mortality on average than cattle on corn based rations. In general, management activities associated with growing cattle (as opposed to fattening) over the first winter were sparing for mortality. Groups of cattle given prophylactic vaccines or drugs within two days of arrival tended to experience higher mortality (not statistically higher) than those cattle not receiving those measures, or cattle groups recieving the same prophylactics more than 48 hours after arrival. However, these results require validation in the remaining years of the study. Fibrinous pneumonia was the most frequent diagnosis in the calves on postmortem examination.