Timing of Radiotherapy (RT) After Radical Prostatectomy (RP): Long-term outcomes in the RADICALS-RT trial [NCT00541047].

BACKGROUND: The optimal timing of radiotherapy (RT) after radical prostatectomy for prostate cancer has been uncertain. RADICALS-RT compared efficacy and safety of adjuvant RT versus an observation policy with salvage RT for PSA failure. METHODS: RADICALS-RT was a randomised controlled trial enrolling patients with ≥1 risk factor (pT3/4, Gleason 7-10, positive margins, pre-op PSA≥10ng/ml) for recurrence after radical prostatectomy. Patients were randomised 1:1 to adjuvant RT ("Adjuvant-RT") or an observation policy with salvage RT for PSA failure ("Salvage-RT") defined as PSA≥0.1ng/ml or 3 consecutive rises. Stratification factors were Gleason score, margin status, planned RT schedule (52.5Gy/20 fractions or 66Gy/33 fractions) and treatment centre. The primary outcome measure was freedom-from-distant metastasis, designed with 80% power to detect an improvement from 90% with Salvage-RT (control) to 95% at 10yr with Adjuvant-RT. Secondary outcome measures were bPFS, freedom-from-non-protocol hormone therapy, safety and patient-reported outcomes. Standard survival analysis methods were used; HR<1 favours Adjuvant-RT. FINDINGS: Between Oct-2007 and Dec-2016, 1396 participants from UK, Denmark, Canada and Ireland were randomised: 699 Salvage-RT, 697 Adjuvant-RT. Allocated groups were balanced with median age 65yr. 93% (649/697) Adjuvant-RT reported RT within 6m after randomisation; 39% (270/699) Salvage-RT reported RT during follow-up. Median follow-up was 7.8 years. With 80 distant metastasis events, 10yr FFDM was 93% for Adjuvant-RT and 90% for Salvage-RT: HR=0.68 (95%CI 0·43-1·07, p=0·095). Of 109 deaths, 17 were due to prostate cancer. Overall survival was not improved (HR=0.980, 95%CI 0.667-1.440, p=0.917). Adjuvant-RT reported worse urinary and faecal incontinence one year after randomisation (p=0.001); faecal incontinence remained significant after ten years (p=0.017). INTERPRETATION: Long-term results from RADICALS-RT confirm adjuvant RT after radical prostatectomy increases the risk of urinary and bowel morbidity, but does not meaningfully improve disease control. An observation policy with salvage RT for PSA failure should be the current standard after radical prostatectomy.

Lipid kinases play crucial and multiple roles in membrane trafficking and signaling.

Phosphotidylinositols (PIs) are known to play an essential role in membrane trafficking and signaling transduction. PIs serve multiple functions, such as recruitment of cytosolic proteins with PI phosphate (PIP) binding domains and modification of the physical properties of the membranes in which they reside. As substrates for phosphoinositide-specific lipases they function as a switch point in phosphoinositide metabolism. Recent work with epidermal growth factor receptor (EGFR) and colony stimulating factor-1 receptor (CSFR) has identified a possible connection between endocytosis of activated receptors and type-1 phosphatidylinositol-4-phosphate-5-kinase. Furthermore, serine/tyrosine phosphorylation of phosphatidylinositol-4-phosphate-5-kinase seems to be essential for its activities. Indeed, one of the products of the phosphatidylinositol-4-phosphate-5-kinases, PIP2, has been shown to be involved in multiple steps of endocytosis, including the assembly of the clathrin coat, regulation of adaptor proteins, and production of endocytic vesicles via the regulation of dynamin. The discussion in this review focuses primarily on receptors with intrinsic enzymatic activity, specifically on receptor tyrosine kinases (RTKs). We will discuss their structure; mechanism of action and potential role in membrane trafficking and/or signaling through the regulation of phosphatidylinositol phosphate kinases.

Phosphatidylinositol-4-phosphate 5-kinase-1beta is essential for epidermal growth factor receptor-mediated endocytosis.

Phosphatidylinositol-4,5-bisphosphate (PIP(2)) is known to play an important role in signal transduction and membrane trafficking. We show that one enzyme responsible for PIP(2) production, phosphatidylinositol-4-phosphate 5-kinase type 1beta (PIPKbeta), is essential for epidermal growth factor receptor (EGFR)-mediated endocytosis. Expression of murine PIPKbeta in NR6 cells expressing EGFR strikingly increased receptor internalization. Moreover, the kinase was shown to form an immunoprecipitable complex with EGFR. Expression of either a truncated kinase or a kinase dead mutant inhibited EGFR endocytosis and also blocked the membrane recruitment of PIPKbeta and both clathrin light chain and dynamin. Our results delineate a novel mechanism by which PIPKbeta regulates receptor-mediated endocytosis and receptor tyrosine kinase membrane traffic.

Aggresomes resemble sites specialized for virus assembly.

The large cytoplasmic DNA viruses such as poxviruses, iridoviruses, and African swine fever virus (ASFV) assemble in discrete perinuclear foci called viral factories. Factories exclude host proteins, suggesting that they are novel subcellular structures induced by viruses. Novel perinuclear structures, called aggresomes are also formed by cells in response to misfolded protein (Johnston, J.A., C.L. Ward, and R.R. Kopito. 1998. J. Cell Biol. 143:1883--1898; García-Mata, R., Z. Bebök, E.J. Sorscher, and E.S. Sztul. 1999. J. Cell Biol. 146:1239--1254). In this study, we have investigated whether aggresomes and viral factories are related structures. Aggresomes were compared with viral factories produced by ASFV. Aggresomes and viral factories were located close to the microtubule organizing center and required an intact microtubular network for assembly. Both structures caused rearrangement of intermediate filaments and the collapse of vimentin into characteristic cages, and both recruited mitochondria and cellular chaperones. Given that ASFV factories resemble aggresomes, it is possible that a cellular response originally designed to reduce the toxicity of misfolded proteins is exploited by cytoplasmic DNA viruses to concentrate structural proteins at virus assembly sites.

A novel method of guideline development for the diagnosis and management of mild to moderate hypertension.

BACKGROUND: There are large numbers of clinical guidelines available covering many clinical areas. However, the variable quality of their content has meant that doctors may have been offered advice that has been poorly researched or is of a conflicting nature. It has been shown that local involvement in guideline development increases the likelihood of their use. AIM: To develop a guideline to be used by general practitioners in six practices in Birmingham from existing evidence-based guidelines. METHOD: Recommendations from the four most cited international hypertension guidelines, and the more recently published New Zealand guidelines, were divided into subject areas and tabulated to facilitate direct comparison. Where there was complete or majority (> or = 3/5) agreement, the recommendation was taken as acceptable for inclusion in the new guideline. Where there was disagreement (< or = 2/5), recommendations were based on the best available evidence following a further MEDLINE literature search and critical appraisal of the relevant literature. Each recommendation was accompanied by a grade of evidence (A-D), as defined by the Canadian Hypertension Society, and an 'action required' statement of either 'must', 'should', or 'could', based on the Eli-Lilly National Clinical Audit Centre Hypertension Audit criteria. The recommendations were summarized into a guideline algorithm and a supporting document. The final format of both parts of the guideline was decided after consultation with the practice teams. The practices individually decided on methods of data collection. RESULTS: The guideline was presented as a double-sided, A4 laminated sheet and an A4 bound supporting document containing a synthesis of the original guidelines in tabular form, a table of the resulting recommendations, and appendices of current literature reviews on areas of disagreement. The content of the final Birmingham Clinical Effectiveness Group (BCEG) guideline differed minimally from any of the original guidelines. CONCLUSION: The main strength of this method of guideline development may lie, not in the actual content of the resulting guideline, but in the strength of ownership felt by the BCEG and the practices following its development. While the full process is unlikely to be possible for general practitioners working outside an academic environment, the techniques used could provide a framework for practitioners to adapt national and international guidelines for use at a local level.

Use of a paper-cut as an adjunct to teaching the Whipple procedure by video.

BACKGROUND: Medical students often experience difficulty comprehending anatomic relationships of complex operations to which they are exposed during surgical clerkship. Pancreaticoduodenectomy, the Whipple procedure, is one such operation. Although video recordings are available to facilitate the learning of the Whipple procedure, commercially available tapes are not self-explanatory to the uninitiated. Since we have previously demonstrated that third-year medical students could learn the operative steps of inguinal herniorraphy by a paper-cutting exercise, we set out to determine whether an exercise of similar design could enhance a student's comprehension of the Whipple procedure. METHODS: Using Adobe Illustrator 5.5 for MacIntosh, an exercise was developed on a 8.5 x 11-inch paper that could be distributed to students for self-administration. The exercise was performed using a #15 scalpel or an iris scissors. Thirty-seven students were randomized into two groups. Each student received a pretest of questions focusing on the Whipple procedure. Group I was shown an 18-minute commercially available teaching video on the Whipple procedure. Group II was given the Whipple origami exercise, which required 20 minutes to complete. A first posttest was administered to each group. Next, the groups switched exercises, and a second posttest was administered. RESULTS: There was no significant difference between the groups' pretest scores (two-tailed t test, P = 0.290). Group I improved its score from an average of 64.21 (SD 14.27) to 67.89 (SD 13.16) after watching the video, and further to 77.89 (SD 14.37) after completing the paper-cut exercise. Group II improved from 60.00 (SD 9.43) to 78.95 (SD 11.00) after performing the paper-cut, but derived no additional measurable benefit from watching the video, average score 74.74 (SD 18.37). After the first exercise, students who performed the paper-cut showed a significantly greater improvement in test scores compared with students who saw the video (P = 0.0035 by Mann-Whitney U). After both groups had completed the exercises, the mean changes from baseline were no longer significantly different (P = 0.58 by Mann-Whitney U). CONCLUSION: As a single educational intervention, the paper-cut exercise was a more effective teaching device than the video in the given time frame. The origami model may be generalized to a variety of surgical procedures and appears to be a valuable adjunct to traditional teaching.

CTCF, a conserved nuclear factor required for optimal transcriptional activity of the chicken c-myc gene, is an 11-Zn-finger protein differentially expressed in multiple forms.

A novel sequence-specific DNA-binding protein, CTCF, which interacts with the chicken c-myc gene promoter, has been identified and partially characterized (V. V. Lobanenkov, R. H. Nicolas, V. V. Adler, H. Paterson, E. M. Klenova, A. V. Polotskaja, and G. H. Goodwin, Oncogene 5:1743-1753, 1990). In order to test directly whether binding of CTCF to one specific DNA region of the c-myc promoter is important for chicken c-myc transcription, we have determined which nucleotides within this GC-rich region are responsible for recognition of overlapping sites by CTCF and Sp1-like proteins. Using missing-contact analysis of all four nucleotides in both DNA strands and homogeneous CTCF protein purified by sequence-specific chromatography, we have identified three sets of nucleotides which contact either CTCF or two Sp1-like proteins binding within the same DNA region. Specific mutations of 3 of 15 purines required for CTCF binding were designed to eliminate binding of CTCF without altering the binding of other proteins. Electrophoretic mobility shift assay of nuclear extracts showed that the mutant DNA sequence did not bind CTCF but did bind two Sp1-like proteins. When introduced into a 3.3-kbp-long 5'-flanking noncoding c-myc sequence fused to a reporter CAT gene, the same mutation of the CTCF binding site resulted in 10- and 3-fold reductions, respectively, of transcription in two different (erythroid and myeloid) stably transfected chicken cell lines. Isolation and analysis of the CTCF cDNA encoding an 82-kDa form of CTCF protein shows that DNA-binding domain of CTCF is composed of 11 Zn fingers: 10 are of C2H2 class, and 1 is of C2HC class. CTCF was found to be abundant and conserved in cells of vertebrate species. We detected six major nuclear forms of CTCF protein differentially expressed in different chicken cell lines and tissues. We conclude that isoforms of 11-Zn-finger factor CTCF which are present in chicken hematopoietic HD3 and BM2 cells can act as a positive regulator of the chicken c-myc gene transcription. Possible functions of other CTCF forms are discussed.

Translocation yield from the mouse spermatogonial stem cell following fractionated X-ray treatments: influence of unequal fraction size and of increasing fractionation interval.

(1) The genetic response of the mouse spermatogonial stem cell to a high dose of X-rays given in two unequal fractions 24 h apart can be dependent upon the order in which the two fractions are given. When 1000 R was administered as 100 R followed by 900 R the recovered translocation yield (22%) was similar to that which can be obtained by extrapolation from lower doses and also to that of a 500 + 500 R 24 h fractionation. By contrast, when the 900 R preceded the 100 R the response was much lower (7.4%), yet still greater than that produced by a single 1000 R treatment (4.5%). The same order of effectiveness was observed for length of sterile period. (2) The sub-additive translocation yields previously obtained with 800 R treatments given in fractions of 500 R and 300 R at intervals of 3-12 days were found to be maintained with intervals up to at least 15 days but additivity was regained by the end of the third week. Sterile period data indicated that with these intervals the germinal epithelium had recovered sufficiently from the first fraction for spermatogenesis to restart before the second fraction was given. (3) It is concluded from the two experiments that (a) 24 h after a radiation exposure the surviving stem cells are more sensitive than formerly both to killing and genetic damage, (b) at this time they are no longer heterogeneous in their radiosensitivities, so that increasing yields of genetic damage may be obtained with increasing dose i.e. there is no fall in yield at higher doses, (c) the change in sensitivity could be a consequence of a synchronization to a sensitive stage in a cell cycle, or to a transitional phase preparatory to entering a different cell cycle. (d) to achieve rapid repopulation of the germinal epithelium the surviving stem cells are stimulated to enter a shorter cell cycle and this is the cause of the sub-additive translocation yields with fractionation intervals of 3-15 days, (e) the recommencement of spermatogenesis is associated with the reestablishment of the heterogeneity in radiosensitivity among the stem cells. At this time additive translocation yields can again be recovered.

Complete identification of endocrine cells in the gastrointestinal tract using semithin-thin sections to identify motilin cells in human and animal intestine.

The present (Wiesbaden) classification of gut endocrine cells relies mainly on ultrastructure and the results of silver impregnation. Correlation with hormone production requires parallel immunology but conventional immune cytochemistry is, in most cases, difficult or at present impossible. The serial, semithin-thin-section technique offers an alternative, which provides absolute correlation between cell type and hormone production. The successful use of the technique is illustrated here by localization of motilin in the enterochromaffin cells of the small intestine.