Factors predictive of an advanced stage of colorectal cancer at presentation - a bi-national study.

AIM: Identifying elements associated with advanced colorectal cancer (CRC) stage may inform understanding of whether advanced disease is a corollary of access to healthcare or tumour biology and in turn allow the use of targeted screening and awareness programmes. The aim of this study was to identify factors that predict advanced stage of CRC at presentation in Australia and New Zealand. METHOD: This was a cross-sectional registry study sourced from the prospectively maintained Binational Colorectal Cancer Audit database of Australia and New Zealand. The primary outcome was stage as defined by the TNM system with associations drawn to demographic and perioperative variables. RESULTS: In total, 25 282 separate cancers were included. Univariate analysis found younger age, treatment at a public facility, increasing American Society of Anesthesiologists (ASA) grade, more distal tumours, and less recent year of surgery to all be associated with more advanced disease; sex and presentation at a rural vs urban hospital had no bearing on this outcome. Logistic regression identified younger age (< 60 years vs > 80 years: OR 1.96; 95% CI 1.80-2.14; P = 0.002), treatment at a public vs private hospital (OR 1.21; 95% CI 1.14-1.28; P < 0.001), increasing ASA grade (ASA4 vs ASA1: OR 1.37; 95% CI 1.17-1.59, P < 0.001) and more distal tumours (mid-low rectal vs right colon tumours: OR 1.52; 95% CI 1.41-1.64; P < 0.001) to be independent predictors of nodal or metastatic disease at presentation. CONCLUSION: Younger age, increasing ASA grade, more distal tumours, and treatment at a public rather than private facility are independently associated with the presence of nodal or distant CRC metastases at diagnosis.

An Improved Detached-Leaf Assay for Phenotyping Net Blotch of Barley Caused by Pyrenophora teres.

Net blotch, caused by Pyrenophora teres, is a major barley (Hordeum vulgare) leaf disease worldwide. P. teres occurs as two forms-P. teres f. teres, and P. teres f. maculata-inducing net and spot-like symptoms, respectively. An intact-seedling assay, where entire seedlings are inoculated by spraying with a conidial suspension, is frequently used for phenotyping net blotch. However, this presents a biosecurity risk in the glasshouse when nonlocal isolates are being screened. Alternatively, a detached-leaf assay (DLA-droplet method) can be used in which leaf segments laid out in a covered tray are inoculated with droplets of a conidial suspension, confining the inoculum. However, using this method, net and spot form symptoms cannot be distinguished from each other. We have developed an improved DLA (DLA-spray method) in which detached whole leaves are sprayed with the inoculum to produce distinct lesions. We compare the results for the three phenotyping methods above using four isolates from both net and spot forms of the disease to inoculate a standard set of eight barley genotypes. Results indicate that the DLA-spray method is a functional, informative and rapid test that readily differentiates the two forms of the pathogen in a biosecure environment.

Controlled surface charging as a depth-profiling probe for mesoscopic layers

Probing the structure of material layers just a few nanometres thick requires analytical techniques with high depth sensitivity. X-ray photoelectron spectroscopy (XPS) provides one such method, but obtaining vertically resolved structural information from the raw data is not straightforward. There are several XPS depth-profiling methods, including ion etching, angle-resolved XPS (ref. 2) and Tougaard's approach, but all suffer various limitations. Here we report a simple, non-destructive XPS depth-profiling method that yields accurate depth information with nanometre resolution. We demonstrate the technique using self-assembled multilayers on gold surfaces; the former contain 'marker' monolayers that have been inserted at predetermined depths. A controllable potential gradient is established vertically through the sample by charging the surface of the dielectric overlayer with an electron flood gun. The local potential is probed by measuring XPS line shifts, which correlate directly with the vertical position of atoms. We term the method 'controlled surface charging' and expect it to be generally applicable to a large variety of mesoscopic heterostructures.

Infliximab in ulcerative colitis is associated with an increased risk of postoperative complications after restorative proctocolectomy.

PURPOSE: Little data exist regarding infliximab use in surgical decision making and postoperative complications in ulcerative colitis. Our goals were to determine the rate of postoperative complications in infliximab-treated ulcerative colitis patients undergoing restorative proctocolectomy and to determine whether three-stage procedures are more often necessary. METHODS: We studied a group of infliximab-treated patients and matched control subjects who underwent two-stage restorative proctocolectomy between 2000 and 2006. Postoperative complications were compared. In addition, the rate of three-stage procedures was compared between all infliximab- and noninfliximab-treated patients. RESULTS: A total of 523 restorative proctocolectomies were performed. In the infliximab group, there were 46 two-stage and 39 three-stage procedures. Covariate-adjusted odds of early complication for the infliximab group was 3.54 times that of controls (P = 0.004; 95 percent confidence interval (CI), 1.51-8.31). The odds of sepsis were 13.8 times greater (P = 0.011; 95 percent CI, 1.82-105) and the odds of late complication were 2.19 times greater (P = 0.08; 95 percent CI, 0.91-5.28) for infliximab. The odds of requirement for three-stage procedures was 2.07 times greater in the infliximab group (P = 0.011; 95 percent CI, 1.18-3.63). CONCLUSIONS: Infliximab increases the risk of postoperative complications after restorative proctocolectomy and has altered the surgical approach to ulcerative colitis. Potential benefits of infliximab should be balanced against these risks.

Quantitative discrimination between oil and water in drilled bore cores via Fast-Neutron Resonance Transmission Radiography.

A novel method utilizing the Fast Neutron Resonance Transmission Radiography is proposed for non-destructive, quantitative determination of the weight percentages of oil and water in cores taken from subterranean or underwater geological formations. The ability of the method to distinguish water from oil stems from the unambiguously-specific energy dependence of the neutron cross-sections for the principal elemental constituents. Monte-Carlo simulations and initial results of experimental investigations indicate that the technique may provide a rapid, accurate and non-destructive method for quantitative evaluation of core fluids in thick intact cores, including those of tight shales for which the use of conventional core analytical approaches appears to be questionable.

High-frame rate imaging of two-phase flow in a thin rectangular channel using fast neutrons.

We have demonstrated the feasibility of performing high-frame-rate, fast neutron radiography of air-water two-phase flows in a thin channel with rectangular cross section. The experiments have been carried out at the accelerator facility of the Physikalisch-Technische Bundesanstalt. A polychromatic, high-intensity fast neutron beam with average energy of 6 MeV was produced by 11.5 MeV deuterons hitting a thick Be target. Image sequences down to 10 ms exposure times were obtained using a fast-neutron imaging detector developed in the context of fast-neutron resonance imaging. Different two-phase flow regimes such as bubbly slug and churn flows have been examined. Two phase flow parameters like the volumetric gas fraction, bubble size and mean bubble velocities have been measured. The first results are promising, improvements for future experiments are also discussed.

Death-associated protein kinase increases glycolytic rate through binding and activation of pyruvate kinase.

Death-associated protein kinase (DAPk), a multi-domain serine/threonine kinase, regulates numerous cell death mechanisms and harbors tumor suppressor functions. In this study, we report that DAPk directly binds and functionally activates pyruvate kinase M2 (PKM2), a key glycolytic enzyme, which contributes to the regulation of cancer cell metabolism. PKM2 was identified as a novel binding partner of DAPk by a yeast two-hybrid screen. This interaction was validated in vitro by enzyme-linked immunosorbent assay using purified proteins and in vivo by co-immunoprecipitation of the two endogenous proteins from cells. In vitro interaction with full-length DAPk resulted in a significant increase in the activity of PKM2. Conversely, a fragment of DAPk harboring only the functional kinase domain (KD) could neither bind PKM2 in cells nor activate it in vitro. Indeed, DAPk failed to phosphorylate PKM2. Notably, transfection of cells, with a truncated DAPk lacking the KD, elevated endogenous PKM2 activity, suggesting that PKM2 activation by DAPk occurs independently of its kinase activity. DAPk-transfected cells displayed changes in glycolytic activity, as reflected by elevated lactate production, whereas glucose uptake remained unaltered. A mild reduction in cell proliferation was detected as well in these transfected cells. Altogether, this work identifies a new role for DAPk as a metabolic regulator, suggesting the concept of direct interactions between a tumor suppressor and a key glycolytic enzyme to limit cell growth. Moreover, the work documents a unique function of DAPk that is independent of its catalytic activity and a novel mechanism to activate PKM2 by protein-protein interaction.

Control of glycolysis through regulation of PFK1: old friends and recent additions.

Regulation of glucose metabolism is a crucial aspect of cell physiology in normal and disease conditions. Many regulatory events are involved in determining the metabolic fate of glucose and the pathways into which it is directed. The first reaction that commits glucose to the glycolytic pathway is catalyzed by the enzyme phosphofructokinase-1 (PFK-1) and is tightly regulated. One of the most potent activators of PFK-1 is fructose 2,6 bisphosphate (F2,6BP) and its cellular levels are correlated with glycolytic flux. F2,6BP is synthesized and degraded by a family of bifunctional enzymes-the 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (PFKFB). The interplay among F2,6BP levels, the enzymes that generate and degrade it, and PFK-1 activity has important consequences for several different aspects of cell metabolism as well as for systemic metabolic conditions. TIGAR, a recently identified F2,6 bisphosphatase (F2,6BPase), could also contribute to this complexity and participate in shaping the metabolic profile of the cell.

A systems level strategy for analyzing the cell death network: implication in exploring the apoptosis/autophagy connection.

The mammalian cell death network comprises three distinct functional modules: apoptosis, autophagy and programmed necrosis. Currently, the field lacks systems level approaches to assess the extent to which the intermodular connectivity affects cell death performance. Here, we developed a platform that is based on single and double sets of RNAi-mediated perturbations targeting combinations of apoptotic and autophagic genes. The outcome of perturbations is measured both at the level of the overall cell death responses, using an unbiased quantitative reporter, and by assessing the molecular responses within the different functional modules. Epistatic analyses determine whether seemingly unrelated pairs of proteins are genetically linked. The initial running of this platform in etoposide-treated cells, using a few single and double perturbations, identified several levels of connectivity between apoptosis and autophagy. The knock down of caspase3 turned on a switch toward autophagic cell death, which requires Atg5 or Beclin-1. In addition, a reciprocal connection between these two autophagic genes and apoptosis was identified. By applying computational tools that are based on mining the protein-protein interaction database, a novel biochemical pathway connecting between Atg5 and caspase3 is suggested. Scaling up this platform into hundreds of perturbations potentially has a wide, general scope of applicability, and will provide the basis for future modeling of the cell death network.

Acetylcholinesterase-R increases germ cell apoptosis but enhances sperm motility.

Changes in protein subdomains through alternative splicing often modify protein-protein interactions, altering biological processes. A relevant example is that of the stress-induced up-regulation of the acetylcholinesterase (AChE-R) splice variant, a common response in various tissues. In germ cells of male transgenic TgR mice, AChE-R excess associates with reduced sperm differentiation and sperm counts. To explore the mechanism(s) by which AChE-R up-regulation affects spermatogenesis, we identified AChE-R's protein partners through a yeast two-hybrid screen. In meiotic spermatocytes from TgR mice, we detected AChE-R interaction with the scaffold protein RACK1 and elevated apoptosis. This correlated with reduced scavenging by RACK1 of the pro-apoptotic TAp73, an outcome compatible with the increased apoptosis. In contrast, at later stages in sperm development, AChE-R's interaction with the glycolytic enzyme enolase-alpha elevates enolase activity. In transfected cells, enforced AChE-R excess increased glucose uptake and adenosine tri-phosphate (ATP) levels. Correspondingly, TgR sperm cells display elevated ATP levels, mitochondrial hyperactivity and increased motility. In human donors' sperm, we found direct association of sperm motility with AChE-R expression. Interchanging interactions with RACK1 and enolase-alpha may hence enable AChE-R to affect both sperm differentiation and function by participating in independent cellular pathways.

Infected hydrocele following laparoscopic appendectomy: case report.

In the literature, specific reported complications after laparoscopic appendectomy include bowel injury, hemorrhage, wound infection, and cecal fistula. We report the occurrence of infected hydrocele after laparoscopic appendectomy in a 20-year-old man. This complication, to our knowledge, has not yet been described in the literature.

Modified testicular expression of stress-associated "readthrough" acetylcholinesterase predicts male infertility.

Male infertility is often attributed to stress. However, the protein or proteins that mediate stress-related infertility are not yet known. Overexpression of the "readthrough" variant of acetylcholinesterase (AChE-R) is involved in the cellular stress response in a variety of mammalian tissues. Here, we report testicular overexpression of AChE-R in heads, but not tails, of postmeiotic spermatozoa from mice subjected to a transient psychological stress compared with age-matched control mice. Transgenic mice overexpressing AChE-R displayed reduced sperm counts, decreased seminal gland weight, and impaired sperm motility compared with age-matched nontransgenic controls. AChE-R was prominent in meiotic phase spermatocytes and in tails, but not heads, of testicular spermatozoa from AChE-R transgenic mice. Head-localized AChE-R was characteristic of human sperm from fertile donors. In contrast, sperm head AChE-R staining was conspicuously reduced in samples from human couples for whom the cause of infertility could not be determined, similar to the pattern found in transgenic mice. These findings indicate AChE-R involvement in impaired sperm quality, which suggests that it is a molecular marker for stress-related infertility.

Physostigmine antagonizes morphine-induced respiratory depression in human subjects.

The effect of physostigmine on the respiratory depression induced by morphine was studied in human subjects who received morphine as part of their preanesthetic medication. After pretreatment with droperidol (2.5-5 mg, iv) to prevent nausea, the change in minute ventilation was measured in 16 patients in response to increasing concentrations of inspired CO2 (CO2-response curve) by the rebreathing method. This was repeated 30 min after morphine (0.166 mg/kg, iv) in nine subjects and in seven controls who did not receive morphine and again 5-10 min after physostigmine (13-33 micrograms/kg, iv) in all subjects. All subjects were given N-butylhyoscine hydrobromide (5 mg, iv) to antagonize any peripheral cholinergic effects of physostigmine. Morphine decreased the mean slope of the CO2-response curve from 1.78 +/- 0.18 to 1.12 +/- 0.14 1 X min-1 X mmHg-1 (P less than 0.01) and increased the alveolar PCO2 for a fixed minute ventilation (position of curve) from 45.0 +/- 1.3 to 51.9 +/- 1.5 mmHg (P less than 0.001). Physostigmine restored the mean slope after morphine to control value, i.e., 1.79 +/- 0.231 X min-1 X mmHg-1, and position to 46.2 +/- 1.2 mmHg (P less than 0.001). Physostigmine did not increase the slope or alter the position of the CO2-response curves of subjects given droperidol alone. The authors conclude that physostigmine can reverse the respiratory depressant effect of morphine and restore the sensitivity of the respiratory center of CO2, presumably by raising acetylcholine levels in the brain after these have been reduced by morphine.