No abstract

The close association of human papillomavirus type 16 DNA with a majority of cervical carcinomas implies some role for the virus in this type of cancer. To define the transforming properties of HPV-16 DNA in vitro we have now performed transfection experiments on baby rat kidney cells using HPV-16 DNA in conjunction with an activated ras gene. We have demonstrated that a 6.6-kb DNA fragment, containing the early genes of HPV-16 under the control of Moloney murine leukaemia virus long terminal repeats (MoMuLV-LTRs), cooperates with EJ-ras in transforming these cells. Both DNAs are required and neither alone is effective. The cooperating activity appears to reside in a protein or proteins derived from the E6/E7 region of the HPV-16 genome.

The spatial coherency of strong ground motion from fifteen earthquakes recorded by the Lotung LSST strong motion array is analyzed. The earthquakes range in magnitude from 3.7 to 7.8 and in epicentral distance from 5 to 80 km. In all, a total of 533 station pairs are used with station separations ranging from 6 to 85 meters. Empirical coherency functions for the horizontal component S-waves appropriate for use in engineering analyses are derived from these data. The derived coherency functions are applicable to all frequencies and to separation distances up to 100 m. For these short station separations, the coherency decreases much faster with increasing frequency than with increasing station separation. The computed coherencies indicate that at high frequencies (>10 Hz) over 25 percent of the power of the ground motion is random for station separations greater than 30 m.

The clinical implications of newly acquired left bundle-branch block (LBBB) were examined prospectively in the Framingham Study population. During 18 years of observation 55 people developed LBBB. The mean age at the onset of LBBB was 62; LBBB occurred largely in people with antecedent hypertension, cardiac enlargement, coronary heart disease, or a combination of these. Coincident with or subsequent to the onset of LBBB, 48% developed clinical coronary disease or congestive failure for the first time. Throughout the entire period of observation only 11% remained free of clinically apparent cardiovascular abnormalities. Within 10 years of the onset of LBBB, 50% had died from cardiovascular diseases. In men, the appearance of LBBB contributed independently to an increased risk of cardiovascular disease mortality. Comparison with age- and sex-matched control subjects free from LBBB confirmed that in the general adult population, newly acquired LBBB is most often a hallmark of advanced hypertensive or ischemic heart disease, or both.

Coronary perforation is an uncommon but potentially life-threatening complication of percutaneous coronary intervention. The use of both atheroablative technologies for coronary intervention and adjunctive platelet glycoprotein blockade pharmacology may increase the incidence of or risk for life-threatening bleeding complications following the occurrence of coronary artery perforation. The interventional database for 6,214 percutaneous coronary interventions performed between January 1995 and June 1999 was analyzed. Hospital charts and cine angiograms for all patients identified in the database as having had coronary perforation were reviewed. Coronary perforation complicated 0.58% of all procedures and was more commonly observed in patients with a history of congestive heart failure and following use of atheroablative interventional technologies (2.8%). There was no association of abciximab therapy with either the incidence of or classification for coronary perforation. Adverse clinical outcomes (death, emergency surgical exploration) were related to the angiographic classification of perforation and were more frequently observed in patients who experienced a class 3 coronary perforation. These data suggest that specific clinical and procedural demographic factors are associated with the occurrence and severity of angiographic coronary perforation. An angiographic perforation class-specific algorithm for treatment of coronary perforation is proposed.