Fusion of Newcastle disease virus with liposomes: role of the lipid composition of liposomes

We demonstrate here that fusion occurs between the membrane of the Newcastle disease virus (NDV) and liposomes. Fluorescence dequenching studies (using Rhodamine-bearing viral envelopes) revealed the mixing of the lipids constituting the viral and liposomal membrane. The digestion of internal viral proteins by trypsin-containing liposomes indicated the mixing of the internal aqueous compartments. This last assay is independent of exchange of lipids between liposomal and viral membrane in the absence of fusion. Investigation of the effects of liposomal composition indicated that the presence of phosphatidylethanolamine and gangliosides are essential to optimize fusion. The fact that the Newcastle disease virus membrane can fuse with liposome also confirms that fusion must be determined by the viral proteins and could be mostly independent of the nature or presence of the host proteins.

Repopulating the Countryside: A 1980 Census Trend

Census data confirm that in the 1970's population grew more rapidly outside than inside metropolitan territory, reversing a historic pattern. The new data reveal that the dispersion of population growth beyond metropolitan areas was not so much a movement to small towns as a movement to the open countryside. The trends appear strong enough to suggest a new shift toward rural life-styles.

Cardiomyopathies characterized by evidence of resistance to left ventricular inflow

Restrictive cardiomyopathy characterized by evidence of left ventricular inflow obstruction was studied in four cases--one child and three adults. In three of the cases, including the child, there was pathologic evidence of hypertrophic cardiomyopathy with asymmetric septal hypertrophy. In the fourth case, no cardiac disease was identified as the anatomic basis for the inflow restriction. This latter case broadens the concept of restrictive cardiomyopathies.

Correlation of electrocardiographic and pathologic findings in healed myocardial infarction

A correlative study in 50 cases of healed myocardial infarction compared the 12 lead electrocardiogram with pathologic observations. The electrocardiogram was interpreted according to established Minnesota codes with some modifications. The following conclusions were reached: (1) The electrocardiogram underestimates the extent of myocardial infarction. (2) When a healed myocardial infarct at a specific location is recognized with electrocardiographic criteria, it is likely that there are unrecognized infarcts involving other areas of the left ventricle. (3) Infarctions involving the lateral and inferobasal areas are frequently unrecognized. (4) The electrocardiogram is more likely to miss myocardial infarcts in patients with multiple, than in those with single, electrocardiographically diagnosed infarcts. (5) Apical myocardial infarction does not appear to have specific electrocardiographic findings, other than those related to general infarct localization by electrocardiogram, particularly in patients with anteroseptal or anterolateral infarction. (6) Abnormal Q waves, generally thought to indicate transmural myocardial infarction, are frequently found in subendocardial infarction. (7) The simplified electrocardiographic classification of myocardial infarct site (anteroseptal, inferior, anterolateral) used in this study is preferable to more detailed classifications previously suggested by others.