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Minimally invasive diagnostic techniques in evaluating patients with breast disease have been increasingly utilized and accepted by physicians and patients over recent years. The incorporation of stereotactic core needle biopsy and ultrasound-guided core needle biopsy into the office practice of evaluating patients with breast disease by our surgical faculty has been met favorably. These procedures are readily learned by surgeons. The judicious use of these procedures is evidenced by the malignancy rate of core biopsies of 16 per cent, identical to the historical rate for needle localization assisted excisional biopsy at our institution. Core breast biopsy expedites definitive diagnosis and optimizes patient convenience. Reimbursement is highly variable, and active physician participation in negotiating with payors to insure that costs are met is essential.

A 3' co-terminus of two early herpes simplex virus type 1 mRNAs has been identified using the nuclease -S1 mapping procedure with cloned virus DNA probes. These mRNAs (5.0 kb and 1.2 kb), located within the genome region 0.56-0.60, are unspliced and are transcribed rightwards on the prototype genome orientation. The position of their 3' ends has been located on the virus DNA sequence and lies downstream from the polyadenylation signal 5'-AATAAA-3'. This hexanucleotide sequence also was present in the complementary DNA strand and was shown to be the polyadenylation signal for a leftwards-transcribed late mRNA. The abundance within the cytoplasm of the 5.0 kb and 1.2 kb mRNAs was investigated. Results indicated that these mRNAs were regulated in concert. It is suggested that sequences at the 3' co-terminus may be involved in their regulation.

Nuclease S1 and exonuclease VII analyses of immediate-early (IE) mRNA-2 of herpes simplex viruses types 1 and 2 (HSV-1, HSV-2) show them to be unspliced and of similar length. The DNA sequences around the 5' and 3' termini have been determined. Comparison of the sequences around the 5' ends reveals several common features. (1) Four discrete blocks of upstream homology which are precisely colinear with respect to the 5' termini of the mRNAs; the blocks include the 'TATA' box, a G-C rich sequence and a sequence (AATTAAATACAT) which may be involved in the coordinate induction of the IE class of genes. (2) Several copies of the sequence CCCCGCCC, found in different upstream positions in HSV-1 and HSV-2, which may be important in the expression of a wide variety of eukaryotic genes. (3) Potential hairpin structures in the region of the 5' termini which are present at similar locations in HSV-1 and HSV-2. Sequence comparison around the 3' termini of IEmRNA-2 reveals high homology at the proposed C-terminus of the polypeptide.

A modular system for assaying the activity of transcriptional regulatory signals based on herpes simplex virus (HSV) promoter and terminator sequences linked to the bacterial chloramphenicol acetyltransferase (CAT) gene has been used to study activation of HSV immediate early (IE) gene expression. Insertion of the SV40 72 base pair (bp) repeat increased mRNA levels by 15-fold thus demonstrating the ability of the HSV IE promoter to respond to a heterologous enhancer. A fragment containing part of the intergenic region located between HSV-2 immediate early (IE) genes-3 and -4/-5 increased mRNA levels by 5-fold in response to transactivation by an HSV virion structural polypeptide. The HSV activator fragment increased mRNA levels by 2-fold in the absence of transactivation indicating that cellular proteins are involved in IE gene expression. From HSV-1/HSV-2 DNA sequence comparisons we previously proposed that a DNA sequence, consensus TAATGARAT, present upstream of all HSV-1 and HSV-2 IE genes was required for the co-ordinate induction of IE genes. We show here that a synthetic oligonucleotide containing TAATGARAT conferred the ability to stimulate CAT activity only on transactivation: two copies of TAATGARAT stimulated expression by 2-fold while six copies gave an 8-fold increase. This activation, which was not dependent on orientation of the TAATGARAT sequence, directly demonstrates that TAATGARAT is a component of the IE gene activation sequence.