Intracoronary stenting without intravascular ultrasound guidance followed by antiplatelet therapy with aspirin alone in selected patients.

One hundred selected patients with 103 lesions were treated with the deployment of 117 Palmaz-Schatz stents without the use of intravascular ultrasound, followed by antiplatelet therapy with aspirin alone. Angiographic and clinical follow-up revealed 2 stent thromboses; 3 stents required redilation, and 3 patients required intervention for disease progression elsewhere, suggesting that this approach can be applied effectively in selected patients.

Single chain antibody variable regions.

The use of antibodies or antibody fragments for targeting tumors (either for tumor imaging or as carriers for drugs or toxins), has encountered problems of clearance, and non-specific or inefficient binding in clinical trials. A novel approach, linking two antibody variable fragments (Fvs), with a short peptide to generate a continuous polypeptide chain, may be able to overcome some of these problems. Since these single chain antibody variable regions (scFvs), are transcribed from constructed 'genes', large-scale production in, for example, E. coli, should be straightforward.

General organization of protein in HeLa 40S nuclear ribonucleoprotein particles.

The majority of the protein mass of HeLa 40S heterogeneous nuclear ribonucleoprotein monoparticles is composed of multiple copies of six proteins that resolve in SDS gels as three groups of doublet bands (A1, A2; B1, B2; and C1, C2) (Beyer, A. L., M. E. Christensen, B. W. Walker, and W. M. LeStourgeon. 1977. Cell. 11: 127-138). We report here that when 40S monoparticles are exposed briefly to ribonuclease, proteins A1, C1, and C2 are solubilized coincidentally with the loss of most premessenger RNA sequences. The remaining proteins exist as tetramers of (A2)3(B1) or pentamers of (A2)3(B1)(B2). The tetramers may reassociate in highly specific ways to form either of two different structures. In 0.1 M salt approximately 12 tetramers (derived from three or four monoparticles) reassemble to form highly regular structures, which may possess dodecahedral symmetry. These structures sediment at 43S, are 20-22 nm in width, and have a mass near 2.3 million. These structures possess 450-500 bases of slowly labeled RNA, which migrates in gels as fragments 200-220 bases in length. In 9 mM salt the tetramers reassociate to form 2.0 M salt-insoluble helical filaments of indeterminant length with a pitch near 60 nm and diameter near 18 nm. If 40S monoparticles are treated briefly with nuclease-free proteases, the same proteins solubilized by nuclease (A1, C1, and C2) are preferentially cleaved. This protein cleavage is associated with the dissociation of most of the heterogeneous nuclear RNA. Proteins A2 and B1 again reassemble to form uniform, globular particles, but these sediment slightly slower than intact monoparticles. These findings indicate that proteins A1, C1, and C2 and most of the premessenger sequences occupy a peripheral position in intact monoparticles and that their homotypic and heterotypic associations are dependent on protein-RNA interactions. Protein cross-linking studies demonstrate that trimers of A1, A2, and C1 exist as the most easily stabilized homotypic association in 40S particles. This supports the 3:1 ratio (via densitometry) of the A and C proteins to the B proteins and indicates that 40S monoparticles are composed of three or four repeating units, each containing 3(A1),3(A2),1(B1),1(B2),3(C1), and 1(C2).

Intakes of vitamins and minerals by pregnant women with selected clinical symptoms.

Toxemia in pregnancy is characterized by a combination of at least two of the following clinical symptoms: hypertension, edema, and proteinuria. In this study the dietary intakes of young pregnant women attending a Maternal and Infant Care Program at Tuskegee Institute were evaluated for selected vitamins and minerals. Women with toxemia were identified, and women without toxemia served as controls. The toxemia group generally consumed lesser amounts of vitamins and minerals than the controls. However, both groups were deficient (less than two-thirds RDA) in calcium, magnesium, vitamin B6, vitamin B12, and thiamin. Milk, meat, and grains supplied an appreciable proportion of each vitamin except vitamin A, which was found primarily in the two vegetable groups. Meat and grains contained the greatest quantities of minerals, but milk provided a relatively good proportion of potassium, calcium, magnesium, and phosphorus. Anemia was not related to the incidence of toxemia. Women exhibiting anemia consumed smaller amounts of vitamins studied than did women without anemia.

The release of 40S hnRNP particles by brief digestion of HeLa nuclei with micrococcal nuclease.

Brief digestion of HeLa nuclei with mirococcal nuclease releases monomer hnRNP particles as well as monomer and polynucleosomes. Sucrose gradient analysis of the nuclease released material reveals a series of small A260 peaks overlapping a more predominant peak in the 40S region of the gradient. Analysis of the proteins, DNa, and RNA in successive gradient fractions has confirmed that the smaller peaks are monomer and polynucleosomes, and that the larger peak is 40S hnRNP. Like 40S particles isolated by low salt extraction or by sonication, the nuclease released particles are composed of rapidly labeled RNA associated with a group of non-histone proteins the most predominant of which are the 32,000-44,000 MW proteins previously identified as core hnRNP proteins. These results provide further evidence that 40S hnRNP particles exist as discrete structural components of larger in vivo ribonucleoprotein complexes.