An evaluation of the effects of a service change from epidurals to rectus sheath catheters on postoperative pain.

Epidurals are frequently used as part of multi-modal perioperative analgesia. They are widely accepted as providing excellent pain relief but are associated with side-effects, have a significant failure rate and can limit a patient's mobility. We report on our use of rectus sheath catheters (RSCs), in conjunction with intravenous opiate via patient controlled analgesia (PCA), as a means of providing analgesia post-laparotomy for gynaecological oncological patients. Our experience is that this offers an alternative method of providing equivalent analgesia, avoiding the risks associated with epidural use and possibly has a role in reducing length of patient stay, although this requires further investigation.

Delays in treating endometrial cancer in the South West of England.

BACKGROUND: Poor cancer survival rates in the United Kingdom are often blamed on delayed medical care. A local audit of endometrial cancer revealed a variety of preventable delays. We surveyed practice in the South West of England to see if this was an isolated or widespread problem. METHODS: All 15 hospitals in the South West of England collected information prospectively from all women with endometrial cancer over 3 months in the spring of 2009. RESULTS: There were delays in all stages of the uterine cancer pathway. Excluding extraneous cases, 52% of women waited more than a month and 12% waited more than 6 months to see their GP from the onset of symptoms. Almost half the cases said they were unaware that abnormal bleeding was a symptom of cancer. Only a quarter of women had treatment within 31 days from the outpatient visit to first definitive treatment and 18% waited more than the target of 62 days for their treatment. CONCLUSIONS: Significant treatment delays occur because women do not report bleeding. If this is replicated throughout Britain, approximately 1000 women per year will delay presentation for at least 3 months and 600 will wait for more than 6 months.

Obstetric management following fertility-sparing radical vaginal trachelectomy for cervical cancer.

Radical vaginal trachelectomy now affords a fertility-sparing procedure for the treatment of early-stage cervical cancer in young women. Subsequent obstetric management within this group of women remains a challenge to the obstetrician, with risks of premature labour a continuing probability throughout pregnancy. Here we describe four cases of successful pregnancy following radical vaginal trachelectomy within our unit. The merits of early antenatal intervention, regular lower uterine segment length monitoring and use of daily progesterone pessaries are discussed, alongside the current supportive evidence. We conclude with a discussion of proposed recommendations for obstetric management of pregnancy in women post-radical vaginal trachelectomy.

Kinetics and efficiency of polyadenylation of late polyomavirus nuclear RNA: generation of oligomeric polyadenylated RNAs and their processing into mRNA.

The rate and efficiency of polyadenylation of late polyomavirus RNA in the nucleus of productively infected mouse kidney cells were determined by measuring incorporation of [3H]uridine into total and polyadenylated viral RNAs fractionated by oligodeoxythymidylic acid-cellulose chromatography. Polyadenylation is rapid: the average delay between synthesis and polyadenylation of viral RNA in the nucleus is 1 to 2 min. However, only 10 to 25% of viral RNA molecules become polyadenylated. Polyadenylated RNAs in the nucleus are a family of molecules which differ in size by an integral number of viral genome lengths (5.3 kilobases). These RNAs are generated by repeated passage of RNA polymerase around the circular viral DNA, accompanied by addition of polyadenylic acid to a unique 3' end situated 2.2 + n(5.3) kilobases from the 5' end of the RNAs (n can be an integer from 0 to at least 3). Between 30 and 50% of the sequences in nuclear polyadenylated RNA are conserved during processing and transport to the cytoplasm as mRNA. This is consistent with the molar ratios of nuclear polyadenylated RNAs in the different size classes, and it suggests that most polyadenylated nuclear RNA is efficiently processed to mRNA. Thus, the low overall conservation of viral RNA sequences between nucleus and cytoplasm is explained by (i) low efficiency of polyadenylation of nuclear RNA and (ii) removal of substantial parts of polyadenylated RNAs during splicing. The correlation between inefficient termination of transcription and inefficient polyadenylation of transcripts suggests that these two events may be causally linked.

Use of a novel S1 nuclease RNA-mapping technique to measure efficiency of transcription termination on polyomavirus DNA.

We devised a strategy to measure the efficiency of transcription termination in vivo by RNA polymerase on polyomavirus DNA. Pulse-labeled nuclear RNA was hybridized with a single-stranded polyomavirus DNA fragment which spans the transcription initiation region. Hybrids were treated with RNase, bound to nitrocellulose filters, eluted with S1 nuclease, and analyzed by gel electrophoresis. The ratio of full-length to less-than-full-length DNA-RNA hybrids was used to calculate transcription termination frequency. We found that 50% of the polymerases terminated per traverse of the L DNA strand during the late phase of infection. The method for mapping in vivo pulse-labeled RNAs which we developed is potentially useful for studying unstable cellular or viral RNAs.

RNA polymerases stall and/or prematurely terminate nearby both early and late promoters on polyomavirus DNA.

Levels of transcription within the E and L strands of the five major PstI fragments of polyomavirus (strain AT3) were measured by pulse-labeling RNA both in infected cells and in isolated nuclei or viral transcription complexes during the late phase of infection. Quantification was assured by hybridization to single-stranded DNAs in solution followed by collection of hybrids on nitrocellulose filters and ribonuclease treatment. The level of in vivo transcription in the region of the early (E strand) promoter was two- to threefold higher than that in all other E-strand regions, suggesting that most RNA polymerases prematurely terminate transcription shortly downstream from this promoter during the late phase. In vitro transcription levels in this region were five- to tenfold higher than in the remainder of the E strand, suggesting that many RNA polymerases 'stall' shortly after initiation in vivo but can be reactivated and continue transcription in vitro upon exposure to detergents and high salt solution. Some premature termination nearby the late (L strand) promoter was also detected by the same method. Strikingly, many RNA polymerases also stalled on the L strand in the region of the early promoter, some 5 x 10(3) bases downstream from the late promoter. Treatment of cells with dichlororibofuranosylbenzimidazole did not affect polymerases that stalled or terminated prematurely, but strongly reduced the presence of polymerases that normally transcribed throughout the entire E or L strand. Examination of the size of RNA chains produced during in vitro incubations showed that many polymerases stalled in vivo within 50 to 100 nucleotides downstream from the initiation sites on both DNA strands. The number of polymerases active in vitro at the E strand promoter was similar to the number of polymerases at the L strand promoter. However, in contrast to L-strand transcription, most of the polymerases that initiated at the E-strand promoter were incapable of extended transcription in vivo. These results suggest that large T antigen-mediated repression of E-strand transcription is not simply due to the exclusion of RNA polymerases from the early promoter. Stalling and/or premature termination by RNA polymerases shortly downstream from the early promoter appears to be a mechanism by which temporal regulation of polyomavirus gene expression can be effected.

Production of active polyomavirus large T antigen in yeast Pichia pastoris.

The coding region of polyomavirus large T antigen was engineered into the genome of the methylotrophic yeast Pichia pastoris by use of the vector pHIL-D2. Expression of large T antigen was induced by methanol under the control of the strong alcohol oxidase (AOX1) promoter. Large T antigen was purified by immunoaffinity chromatography. We showed that yeast-derived large T antigen bound specifically to a DNA fragment that contains the polyomavirus replication origin, protected the four known major binding sites in the origin against DNase I digestion, and could unwind the strands of an origin-containing DNA fragment in an ATP-dependent manner. This system therefore provides a convenient and inexpensive source of biologically active polyomavirus large T antigen for in vitro studies.

Enhanced binding to origin DNA at low pH enables easy detection of polyomavirus large T antigen by gel mobility shift assay of unfixed complexes.

Enhanced, stable binding by polyomavirus large T antigen to the viral DNA replication origin at pH 6 allowed the development of a gel mobility shift assay for the detection of large T antigen. Such assays were not possible at pH 7.6 without previous fixation, due to instability of the complexes. We demonstrated that the gel mobility shift assay at pH 6 is very sensitive, allowing the detection of as little as 5 ng large T antigen, and is highly specific for DNA containing G(A/G)GGC target sequences. This method was used to detect large T antigen in crude cell lysates from transformed yeast cell lines or nuclear extracts from infected insect cells. Large T antigen-DNA complexes remained at or near the loading well in 5% acrylamide or 1.5% agarose gels, indicating that these complexes are very large. Glycerol gradient analysis showed that protein-DNA complexes formed at pH 6 were massive, and that large T antigen also formed large complexes when incubated at low pH in the absence of DNA. These results show that pH has a major effect on binding of large T antigen to its multiple target sites in the viral origin of DNA replication, presumably by affecting protein-protein interactions that are important for the stability of large T antigen-DNA complexes.

Haemoccult testing as an indicator of recurrent colorectal cancer: a 5-year prospective study.

A prospective study was conducted to assess the value of routine haemoccult testing as an indicator of early luminal recurrence of colorectal cancer. One hundred patients (mean age 72 years) undergoing radical resection (70% Dukes' B and 30% Dukes' C) for colorectal carcinoma were asked to provide 3-monthly haemoccult tests to a special follow-up clinic for a minimum of 5 years. Positive tests underwent further investigation with barium enema and colonoscopy. Patient compliance was 84%. Positive tests were obtained in 14 asymptomatic individuals, five of whom proved to have anastomotic recurrence. Recurrence was also identified in a further patient despite a negative haemoccult test. Three patients with anastomotic recurrence were able to undergo further radical surgery; two were still alive over 5 years after detection of recurrent disease. Haemoccult screening appears to detect increased numbers of patients with luminal recurrence (7.2%) when compared to historical controls (2.1%). Larger studies will be needed to determine if this increased detection rate results in improved long-term survival.

Folic acid targeting of protein conjugates into ascites tumour cells from ovarian cancer patients.

Despite a wealth of in vitro data describing the use of folic acid for drug and DNA delivery into ovarian cancer cell lines, there have been no reports describing the targeting of such compounds to freshly isolated tumour cells. We have carried out a study to determine the usefulness of folic acid as a targeting ligand for ovarian cancer by measuring the uptake of folic acid-BSA-FITC in tumour cells isolated from the ascitic fluid of ovarian cancer patients. In 7 out of 7 patients we have found folic acid mediated uptake of the fluorescently labelled albumin, with the accumulation (average cell fluorescence) and differential uptake (ratio between receptor mediated and fluid phase uptake) varying between patients. Accumulation of folic acid-albumin FITC occurs in ascites tumour cells expressing the epithelial cell marker EMA, with a significant proportion of EMA negative cells also accumulating the conjugate. There is no correlation between cell cycle and uptake of folic acid-BSA-FITC. These results suggest that folic acid-targeting of therapeutics is a promising approach for the treatment of ovarian cancer.

A systematic review of the accuracy of diagnostic tests for inguinal lymph node status in vulvar cancer.

OBJECTIVE: To determine the accuracy of minimally and non-invasive tests to assess the groin node status in squamous cell vulvar cancer. METHODS: A systematic review of published research from 1979 to 2004 that compares the results of tests to determine groin node status with histology at inguinofemoral lymphadenectomy was made. Studies included in the review were those that compared the index test to the standard surgical intervention of inguinofemoral lymphadenectomy and allowed the construction of two-by-two tables. From these tables, sensitivity, specificity, and the likelihood ratios (with 95% confidence intervals) were reported and, where feasible, meta-analysis was used to pool results for each test separately. Sentinel node biopsy using technetium-99m-labelled nanocolloid ((99m)Tc) had a pooled sensitivity and negative LR of 97% (91-100 95% CI) and 0.12 (0.053-0.28 95% CI), respectively, and was the most accurate test reviewed. CONCLUSION: Five diagnostic tests were identified in a total of 29 studies (961 groins). Although the studies were small and the design often poor, this represents the best summary of the data to date. Sentinel node identification using (99m)Tc appeared to be the most promising test for accurately excluding lymph node metastases in squamous cell vulvar cancer and potentially reducing the radicality of surgery. Its efficacy as a tool in reducing the need for radical surgery and associated patient morbidity without reducing survival needs further assessment probably in a randomised control trial.

Efficiency of processing of viral RNA during the early and late phases of productive infection by polyoma virus.

The efficiency of processing of polyoma viral RNA and of its export from nucleus to cytoplasm was measured in primary mouse kidney cells by comparing the initial rates of incorporation of [3H]uridine into cytoplasmic and nuclear viral RNA. Appropriate methods of cell fractionation were chosen to maximize yields of cytoplasmic RNA and to minimize leakage of nuclear RNA. Incorporation of [3H]uridine into cellular 4S RNA in the cytoplasm was followed to monitor pool equilibration and maintenance of an excess of radioactive precursor throughout the experimental period. During the early phase of infection (9 to 11 h, in the presence of 5-fluorodeoxyuridine), viral RNA was rapidly and efficiently exported from nucleus to cytoplasm. Viral RNA appeared in the cytoplasm within 6 min of its synthesis, greater than half of the viral RNA synthesized in the nucleus was exported to the cytoplasm. In contrast, during the late phase of infection (28 to 30 h), viral RNA was exported more slowly, appearing in the cytoplasm 12 to 20 min after its synthesis, and much less efficiently-only 5% of late nuclear transcripts was exported. The poor efficiency of processing of late viral RNA may be, in part, a result of (i) the presence in nuclear transcripts of non-mRNA sequences which are removed during processing; (ii) the presence in nuclear transcripts of multiple copies of mRNA sequences, only one of which is incorporated into mature mRNA; and (iii) inefficient polyadenylation of viral nuclear RNA.

Polyoma virus giant RNAs contain tandem repeats of the nucleotide sequence of the entire viral genome.

The bulk of late virus-specific RNA synthesized in polyoma virus-infected mouse cells is larger than a single strand of poloma DNA. The arrangement of viral nucleotide sequences in these giant polyoma RNAs was studied by electron microscopy of hybrids between purified high molecular weight viral RNA and the HindII-1 fragment of polyoma DNA, which contains 91% of the viral genome. Hybrid molecules containing a short single-stranded gap (corresponding to the 9% of viral sequences not present in HindII-1), flanked by double-stranded regions, were photographed and measured. The majority of hybrid molecules contained no single-stranded loops or branches, showing that all viral sequences are transcribed contiguously and that no nonviral sequences are present in the RNA. Hybrid molecules, containing RNA up to 3.5 times the genome length, had a repeating structure of single-stranded gaps 8% of genome length interspersed with double-stranded regions 89% of genome length, showing that giant polyoma RNAs contain tandem repeats of the nucleotide sequence of the entire viral DNA. A small proportion of hybrid molecules contained single-stranded branches or deletion loops in characteristic positions, indicating that RNA "splicing" may occur on high molecular weight nuclear polyoma RNA.

RNA footprint mapping of RNA polymerase II molecules stalled in the intergenic region of polyomavirus DNA.

RNA polymerase II molecules that transcribe the late strand of the 5.3-kb circular polyomavirus genome stall just upstream of the DNA replication origin, in a region containing multiple binding sites for polyomavirus large T antigen. Stalling of RNA polymerases depends on the presence of functional large T antigen and on the integrity of large T antigen binding site A. To gain insight into the interaction between DNA-bound large T antigen and RNA polymerase II, we mapped the position of stalled RNA polymerases by analyzing nascent RNA chains associated with these polymerases. Elongation of RNA in vitro, followed by hybridization with a nested set of DNA fragments extending progressively farther into the stalling region, allowed localization of the 3' end of the nascent RNA to a position 5 to 10 nucleotides upstream of binding site A. Ribonuclease treatment of nascent RNAs on viral transcription complexes, followed by in vitro elongation and hybridization, allowed localization of the distal end of stalled RNA polymerases to a position 40 nucleotides upstream of binding site A. This RNA footprint shows that elongating RNA polymerases stall at a site very close to the position of DNA-bound large T antigen and that they protect approximately 30 nucleotides of nascent RNA against ribonuclease digestion.

RNA polymerase II pauses in vitro, but does not terminate, at discrete sites in promoter-proximal regions on polyomavirus transcription complexes.

Many RNA polymerases stall and/or prematurely terminate transcription nearby the early and late promoters of polyomavirus in vivo during the late phase of productive infection. In this paper we analyzed the RNAs made when these promoter-proximal RNA polymerases were allowed to elongate their nascent chains in vitro on viral transcription complexes isolated from infected cells. RNA was labeled in the presence of a high specific activity of one [alpha-32P]-ribonucleoside triphosphate (rNTP) (less than 1 microM final concentration) and saturating concentrations of the other three rNTPs. Under these conditions, promoter-proximal RNAs of discrete sizes were produced. We show that these discrete RNA species are produced by pausing of RNA polymerase II due to limiting concentrations of one of the rNTPs, and that the positions of the pause sites depend on which rNTP is limiting. This pausing does not result in release of the RNA polymerase or the nascent RNA chain from the transcription complex, as these chains can be further extended when high concentrations of all four rNTPs are supplied. Our results conflict with the interpretations of other investigators who suggest that formation of discrete RNA products, under similar in vitro conditions, reflects authentic termination by RNA polymerase II.

A rabbit beta-globin polyadenylation signal directs efficient termination of transcription of polyomavirus DNA.

We constructed a viable insertion mutant (ins 5) of polyomavirus which contains, upstream of the L-strand polyadenylation signal, a 94-nt fragment of rabbit beta-globin DNA. Included in this fragment are all of the sequence elements required for efficient cleavage and polyadenylation of rabbit beta-globin RNA. The beta-globin signal was efficiently recognized by the cleavage/polyadenylation machinery in mouse 3T6 cells infected with ins 5, signalling greater than 90% of the polyadenylation events on L-strand RNAs. Furthermore, the presence of this efficient polyadenylation signal resulted in a 1.4- to 2.5-fold increase in the fraction of virus-specific RNAs that were polyadenylated. Most importantly, termination of transcription by RNA polymerase II on ins 5 DNA was also increased compared with wild-type virus; nearly 100% of polymerases terminated per traverse of the ins 5 genome. These findings demonstrate that the rabbit beta-globin insert, which contains a strong polyadenylation signal, also contains at least part of a signal for termination of transcription by RNA polymerase II. These results also show that the multiple, spliced leaders on polyomavirus L-strand mRNAs, which arise as a result of inefficient termination and polyadenylation, are not necessary for efficient virus replication.