[Measurement of troponin I levels in suspected myocardial infarction]

Serum cardiac troponin I-values were compared to conventionally obtained diagnosis in 319 consecutive patients suspected of having myocardial infarction, of which 46 patients were given this diagnosis. All patients with troponin I > 20 micrograms/l (n = 40) also had abnormal creatine kinase and abnormal creatine kinase isoenzyme MB activity. All patients with troponin I values in the range 1.0-19.9 micrograms/l (n = 50) had a diagnosis of heart disease (myocardial angina pectoris, myocardial infarction, arrythmia, heart insufficiency). In this patient group, the creatine kinase measurements showed pathological values in only 12 cases. Troponin I seems to be a sensitive indicator of cardiac cell injury, and measurements of troponin I seems to be useful in ruling out cardiac injury.

Polarized transport of MHC class II molecules in Madin-Darby canine kidney cells is directed by a leucine-based signal in the cytoplasmic tail of the beta-chain

MHC class II molecules are found on the basolateral plasma membrane domain of polarized epithelial cells, where they can present Ag to intraepithelial lymphocytes in the vascular space. We have analyzed the sorting information required for efficient intracellular localization and polarized distribution of MHC class II molecules in stably transfected Madin-Darby canine kidney cells. These cells were able to present influenza virus particles to HLA-DR1-restricted T cell clones. Wild-type MHC class II molecules were located on the basolateral plasma membrane domain, in basolateral early endosomes, and in late multivesicular endosomes, the latter also containing the MHC class II-associated invariant chain and an HLA-DM fusion protein. A phenylalanine-leucine residue within the cytoplasmic tail of the beta-chain was required for basolateral distribution, efficient internalization, and localization of the MHC class II molecules to basolateral early endosomes. However, distribution to apically located, late multivesicular endosomes did not depend on signals in the class II cytoplasmic tails as both wild-type class II molecules and mutant molecules lacking the phenylalanine-leucine motif were found in these compartments. Our results demonstrate that sorting information in the tails of class II dimers is an absolute requirement for their basolateral surface distribution and intracellular localization.

[Measurements of serum activity of creatine kinase and creatine kinase isoenzyme MB in suspected myocardial infarction. Experiences from a hospital material]

Total creatine kinase and the creatine kinase isoenzyme MB activities were measured simultaneously in 767 serum samples from 592 patients with suspected myocardial infarction. The main and obligate finding was that in the 89 patients with verified infarction the fraction of MB-activity related to the total creatine kinase activity lay between 4 and 25%. In 72 patients diagnosed as not-having an infarction this fraction tended to lie below 4%. However, false positives frequently occurred within the lower total creatine kinase activity range.

[The final year of Gustav Mahler]

"I am three times without a country; a Bohemian among Austrians, an Austrian among Germans, and a Jew among all the peoples of the world". This famous quotation is typical of Gustav Mahler (1860-1911) and reflects his difficult and stormy life. His rheumatic mitral valve disease, diagnosed in 1907, was probably asymptomatic until recurrent throat infections put an end to his life. At the time of his death Mahler was at the peak of his career as a conductor, with 90 concerts scheduled for the 1910-11 season. He had completed his 9th and begun his 10th symphony, but would his real task as a composer have survived the serious domestic crisis and threatened his artistic life? "My time will come" said Mahler, and by this he meant the acknowledgement of his music. But this took a long time. Today Mahler's music is played all over the world. Without doubt he is "eternal among the great".

Cluster headache: heart rate and blood pressure changes during spontaneous attacks

The ECG findings before, during and following 81 spontaneous attacks of cluster headache in 24 patients have been recorded using a Holter cardiography system. No significant change in mean heart rate was found during attacks, when all attacks were considered as a group. Attacks which began when patients were awake differed from those which began during sleep as regards changes in mean heart rate. The mean heart rate decreased during the majority (61%) of attacks which began when patients were awake, whereas it remained unchanged or increased during the majority (67.5%) of attacks which began during sleep. The attacks which began when patients were awake also had higher absolute mean heart rate values before, during and following attacks compared to similar values for those attacks which began during sleep. blood pressure was measured during 11 attacks and showed a significant increase in both systolic and diastolic blood pressure. The heart rate and blood pressure in six patients usually increased during induced head pain.