Prognostic value of myocardial lactate dehydrogenase subunit ratio in heart transplant recipients

BACKGROUND: Allograft coronary artery disease (CAD) is a major long-term complication in heart transplant recipients. Unfortunately, methods for early estimation of the likelihood of development of the disease are not currently available. Lactate dehydrogenase (LDH) is composed of heart and muscle subunits. The prevalence of these subunits in LDH isoenzymes (LDH1 through LDH5) is an accurate indicator of myocardial metabolism and allows indirect estimation of oxygen availability to cardiocytes. This study investigated the prognostic value of myocardial LDH composition for the occurrence of morbid events in patients with severe allograft CAD. METHODS: Eighty-eight heart transplant recipients were followed up for a median of 4.3 years. The isoenzymes of LDH and the ratio of the heart and muscle subunits (H/M) were determined in 526 endomyocardial biopsy samples. RESULTS: Eleven patients (12%) died from allograft CAD during follow-up. They had significantly lower H/M ratios compared with event-free patients, with clear differences as early as 6 months after operation. A threshold value of 2.75 was derived from receiver operating characteristic curve analysis. Patients showing H/M values < or =2.75 had a significantly higher mortality rate than did those with higher values (p=.0003). Importantly, the H/M ratio emerged as the most powerful independent prognostic factor of death by allograft CAD (p=.001) in a multivariate model. CONCLUSIONS: Poor myocardial aerobic metabolism estimated through low H/M values was highly predictive of cardiac death resulting from severe allograft CAD. Analysis of LDH isoenzyme profile in routine endomyocardial biopsies might be of clinical value.     

Three-dimensional CT scan of hemimandibular hyperplasia: case report

Transient absorption spectra of adenine, adenosine and 2'-deoxyadenosine 5'-monophosphate (dAMP) arising from 248 nm laser flash photolysis using acetone as a photosensitizer have been observed. The intermediates recorded are assigned to the excited triplet states and dehydrogenated radicals of adenine and its nucleoside and nucleotide. The excited triplet states of adenine and its derivatives are produced via triplet-triplet excitation transfer and observed for the first time, while the dehydrogenated radicals stemming from the interaction of triplet acetone with adenine and its derivatives via electron transfer through a five-member-ring electron donor-acceptor intermediate. The site of dehydrogenation is suggested to be the hydrogen atom on C(8) of the adenine moiety. Moreover, three sets of kinetic parameters of the triplet decay have been determined. The rate constants of the unimolecular decay (k0), the triplet quenching by the ground state (ksq) and by the triplet quencher Mn2+ (kq) are 1.1 x 10(5), 7.9 x 10(4), 3.7 x 10(4) s-1, 6.9 x 10(8), 8.3 x 10(8), 3.6 x 10(8) dm3 mol-1 s-1 and 4.2 x 10(8), 3.5 x 10(8), 6.0 x 10(8) dm3 mol-1 s-1 respectively for adenine, adenosine and dAMP.     

Accumulation and metabolism of uneven fatty acids present in single cell protein

Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron.     

Pi (antitrypsin) typing methods. A comparison of acid starch-gel electrophoresis and isoelectric focusing

The Pi typing methods acid starch-gel electrophoresis (ASGE) and isoelectric focusing (IEF) have been compared by three reference laboratories: 564 samples of phenotypes Pi M, MS and MZ were tested in each of the three laboratories with a 96% agreement on initial typing. The discrepancies are recorded and reasons for disagreement discussed. IEF is a reliable method for Pi typing and gives results comparable to those obtained by ASGE.