Inhibition of Human Mammary Cell Line Proliferation by Membrane Lectin-Mediated Uptake of Ha-ras Antisense Oligodeoxynucleotide

The Ha-ras oncogene promotes cell proliferation. Antisense oligonucleotides complementary to the ras gene sequence encompassing a mutated codon 12 selectively induce a cell proliferation inhibition. However, the concentration required to reach an effective inhibition is high due to the low efficiency of the oligonucleotide crossing through cell membranes, leading to a low concentration in the cytosol and/or the nucleoplasm. In the present paper, we show that anti-ras oligonucleotides linked to a glycosylated carrier, serum albumin bearing mannose 6-phosphate residues, are more efficient than free oligonucleotides or oligonucleotides bound to an unglycosylated carrier at inhibiting proliferation of a human tumor mammary cell line expressing the mutated Ha-ras. Using fluorescein-labeled neoglycoproteins and fluorescein-labeled oligonucleotides bound to neoglycoproteins, flow cytometry and confocal microscopy revealed that (i) these tumor cells express a membrane lectin specific for mannose 6-phosphate-bearing proteins, (ii) the membrane lectin actively mediates the uptake of macromolecules substituted with mannose 6-phosphate, and (iii) the fluorescein-labeled oligonucleotides bound to the neoglycoprotein accumulate in intracellular vesicles. Furthermore, with antisense oligonucleotides carried by the neoglycoproteins, the concentration required to inhibit cell proliferation is lower than that of the carrier-free antisense oligonucleotides.     

Psychological Preparation for Pediatric Oncology Patients Undergoing Painful Procedures: A Methodological Critique of the Research

Hypnosis and cognitive-behavioral packages are effective in preparing pediatric oncology patients for bone marrow aspiration and lumbar puncture. However, the relative efficacy of different preparations has not been determined, and potent components of preparation packages have yet to be identified. Further, factors hypothesized to moderate effectiveness of preparation (e.g., cognitive development) have not been investigated. Finally, due to a failure to employ process measures, the extent to which hypothesized mediators of behavior change (e.g., self-efficacy) are modified by preparation is unclear. Following an overview of empirical investigations, we make recommendations for addressing these limitations in future research.     

Determination of needed radiographic room capacity to serve an emergency department

This study describes a method for determining the number of radiographic rooms devoted to emergency radiology that would be required to keep mean patient waiting time at a desired level. A desired mean waiting time for patients must be determined. In our setting, a mean waiting time of 8 minutes resulted in few complaints. The waiting time then sets the required utilization rate of available capacity. Daily and hourly volume and variability in volume of examinations were measured over a 3-month period. This represents the demand. The needed number of rooms is determined by comparing demand with effective available capacity for different numbers of rooms. To maintain an 8-minute mean waiting time, 50% utilization of capacity is required. Mean demand on Sundays is 176 examinations. Five rooms are required, since this gives a 180-examination effective capacity. Using waiting time as the primary decision criterion for making capacity decisions in emergency radiology has several advantages: the method is easy to use, volume variability is taken into account, and the focus is on service to patients.     

Ancient,highly polymorphic human major histocompatibility complex DQA1 intron sequences

A 438 basepair intron 1 sequence adjacent to exon 2 in the human major histocompatibility complex DQA1 gene defined 16 allelic variants in 69 individuals from wide ethnic backgrounds. In contrast, the most variable coding region spanned by the 247 basepair exon 2 defined 11 allelic variants. Our phylogenetic human intron 1 tree derived by the Bootstrap algorithm reflects the same relative allelic relationships as the reported DQA1 exon 2 tree [Gyllensten and Erlich, Hum Immunol 36:1–10, 1989]. Thus 3′ DQA1 intron 1 and exon 2 have cosegregated since divergence of the human races. Comparison of human alleles to a Rhesus monkey DQA1 first intron sequence found only 10 nucleotide substitutions unique to Rhesus, with the other 428 positions (98%) found in at least one human allele. This high degree of homology reflects the evolutionary stability of intron sequences since these two species diverged over 20 million years ago. Because more intron 1 alleles exist than exon 2 alleles, these polymorphic introns can be used to improve tissue typing for transplantation, paternity testing, and forensics and to derive more complete phylogenetic trees. These results suggest that introns represent a previously underutilized polymorphic resource. © 1994 Wiley-Liss, Inc.