Impact of in situ chemical oxidation on contaminant mass discharge: linking source-zone and plume-scale characterizations of remediation performance

A large-scale permanganate-based in situ chemical oxidation (ISCO) effort has been conducted over the past ten years at a federal Superfund site in Tucson, AZ, for which trichloroethene (TCE) is the primary contaminant of concern. Remediation performance was assessed by examining the impact of treatment on contaminant mass discharge, an approach that has been used for only a very few prior ISCO projects. Contaminant mass discharge tests were conducted before and after permanganate injection to measure the impact at the source-zone scale. The results indicate that ISCO caused a significant reduction in mass discharge (approximately 75%). The standard approach of characterizing discharge at the source-zone scale was supplemented with additional characterization at the plume scale, which was evaluated by examining the change in contaminant mass discharge associated with the pump-and-treat system. The integrated contaminant mass discharge decreased by approximately 70%, consistent with the source-zone-scale measurements. The integrated mass discharge rebounded from 0.1 to 0.2 kg/d within one year after cessation of permanganate injections, after which it has been stable for several years. Collection of the integrated contaminant mass discharge data throughout the ISCO treatment period provided a high-resolution, real-time analysis of the site-wide impact of ISCO, thereby linking source-zone remediation to impacts on overall risk. The results indicate that ISCO was successful in reducing contaminant mass discharge at this site, which comprises a highly heterogeneous subsurface environment. Analysis of TCE sediment concentration data for core material collected before and after ISCO supports the hypothesis that the remaining mass discharge is associated in part with poorly accessible contaminant mass residing within lower-permeability zones.

Laparoscopic resection for recurrent Crohn's disease: safety, feasibility and short-term outcomes

AIM

The safety, feasibility and short-term outcomes of laparoscopic resection were assessed in patients with recurrent ileocolic Crohn's disease.

METHOD

A consecutive series of patients was identified from a prospectively collated database. Data included patient demographics, previous medical and surgical treatment, operative details and postoperative course. Data from the original index open operation were collected retrospectively by review of the case notes.

RESULTS

Between 2005 and 2009, 27 patients [21 women, mean (range) age 31 years (16-51 years)] underwent laparoscopic resection for recurrent ileocolic Crohn's disease. All had histologically confirmed recurrent disease at the ileocolic anastomosis. Five (18.5%) patients required extended resection for Crohn's colitis, three (11.1%) had fistulating disease and one (3.4%) patient had a psoas abscess. The median (range) operative time was 110 min (70-170 min) with a conversion rate of two (7.4%) of 27 patients. The length of stay was 4 days (2-7 days) with time to return to work or full activity of 3.5 weeks (2-7 weeks).

CONCLUSION

Laparoscopic resection of recurrent ileocolic Crohn's disease is safe, feasible and associated with short-term benefits.

Trends towards increased use of the laparoscopic approach in colorectal surgery

AIM

The aim of the study was to identify the trend towards laparoscopic resection in the practice of one surgeon and to determine whether the default approach to all colorectal procedures could be by means of minimally invasive techniques with an associated low rate of conversion.

METHOD

A prospective database of primary colorectal resections under the care of one colorectal surgeon collected between July 2003 and December 2008 was analysed to determine the trend in the use of the laparoscopic approach and the rate of conversion of an intention-to-treat policy for laparoscopic procedures. Patients with recurrent rectal or colonic malignancy were excluded from the study.

RESULTS

A total of 598 patients underwent elective colorectal resection of which 371 (62%) were carried out laparoscopically with a rate of conversion of 3.2%. The proportion of all colorectal resections that were undertaken laparoscopically in the first 1 year was 26% (22/85) (no conversions). This proportion rose to 100% (127/127) in the fifth year of the study of which 4.0% were converted. The introduction of more complex procedures did not have an adverse effect on the trend towards more laparoscopic resections The commencement of a laparoscopic colorectal fellowship in 2006 was associated with a marked increase in the number of laparoscopic cases.

CONCLUSION

A conscious decision to make the laparoscopic approach the default for all colorectal resections can be achieved safely with a low conversion rate. This can be achieved within the context of training a 'novice' laparoscopic colorectal surgeon.

Polyethylene glycol as a hydration agent in oriented membrane bilayer samples

Techniques such as NMR, ESR, fluorescence depolarization, and neutron scattering are commonly used to investigate the physical properties of membranes. Oriented membrane bilayer systems (single crystals) are often employed in these investigations. It is important to know and be able to control the level of hydration in these samples. In particular, one must have confidence that a sample is in fact "fully hydrated" and remains so during the course of the experiment. Full hydration is difficult to obtain by hydrating oriented samples using water-saturated vapor. An alternative method for hydrating oriented samples is to surround the oriented sample by a polymer solution. Higher hydration levels are achieved using this method. Three nuclear magnetic resonance studies using headgroup deuterated 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine (DPPC) were done to compare the hydration level of oriented headgroup samples surrounded by a polymer/water solution and fully hydrated multibilayer dispersions. Transition temperatures, quadrupolar splittings (at 50 degrees C) and spin-lattice relaxation times (at 50 degrees C) were measured. The simple tests of the transition temperature and quadrupolar splitting to determine full hydration, as my results show, are not sufficient. In this paper I demonstrate that more fully hydrated samples can easily be achieved by surrounding the oriented sample with a 5 wt% polyethylene glycol/water solution than by hydrating in water saturated vapor.

Developing unplanned care teams in Scotland: evaluating outcomes

Mental health nursing, along with other professional groups, has had to adapt to new ways of delivering health services, often in response to government policy. Consequently, traditional professional boundaries and roles are being rapidly and consistently expanded, often requiring coordinated responses across strategic, educational and clinical domains to ensure service users experience high-quality mental health interventions. This paper explores and evaluates such a coordinated response in developing unplanned care services in Scotland. The evaluation, placed within a framework of realistic evaluation, highlights not only the efficacy of the provided training and education for new roles within unplanned care, but also that emotionally intelligent capabilities are required to successfully implement the level of change currently being experienced within the UK mental health services.

Reliable change indices and regression-based measures for the Rey-Osterreith Complex Figure test in partial epilepsy patients

The Rey-Osterreith Complex Figure (ROCF) is commonly used in evaluations of patients undergoing epilepsy surgery. We assessed test-retest performance on ROCF in 30 partial epilepsy patients (mean interval = 33.7 months) to derive reliable change indices (RCIs) and regression-based measures for change. ROCF reproductions were rescored by three raters (IRR Copy: 0.963; Delayed Recall: 0.986). The derived adjusted RC (90% CI) cutoff values for the ROCF Copy were (<or=-6.5, >or=8.4) and were (<or=-6.8, >or=10.0) for the Delayed Recall. Results from regression-based analyses were negative, using age, education, seizure duration, and age of onset, whereas a baseline score was a significant predictor of a follow-up score. The results provide a means to evaluate long-term outcome in epilepsy patients using the ROCF.

iGenomicViewer, a Gynecologic Oncology Group software library for the creation of highly customizable, portable, interactive, and linked visualizations of high throughput genomic data

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Background: An R software library was created with the goal of creating customizable, platform independent, and portable visualization tools for the annotation, dissemination and interrogation of high dimensioned genomic data. Methods: A set of R functions were created to extend the functionality of the sendplot R library. The functions were applied to BAC aCGH data generated for several GOG studies. Results: The iGenomicViewer function calls created and populated a directory structure which was then ported to a password protected server for interrogation by research team members. The linked html and image output allows users to examine genome wide plots of aberration frequencies and p-values and then drill down to visualizations of regions of interest. Users can interrogate a panel of plots which includes: 1) a heat map of the aCGH data for with tool-tip display of sample and assay specific data (e.g., assay values, sample IDs, and hyperlinks to UCSC browser and sample specific images); 2) a set of interactive annotation tracks which display location of cancer, disease and DNA repair genes; and 3) a plot which displays -log10 p-values and/or aberration frequencies for the BAC assays depicted in the heatmap. For the smallest regions of interest, the panel of plots contains a tiled heatmap which depicts the overlap and gaps in BAC coverage and their alignment with the gene locations represented in the adjacent annotation track. Conclusions: The iGenomicViewer library provides open source software for creation of customizable visualization tools for collaborative research projects involving high dimensioned genomic data.

No significant financial relationships to disclose.

A Gynecologic Oncology Group study of frequent copy number aberrations in African American versus Caucasian women with stage I versus stage IIIC/IV endometrioid endometrial cancer

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Background: An array-based comparative genomic hybridization (aCGH) analysis was performed to determine if frequent (>40%) copy number aberrations (CNAs) exist in African American (AA) versus Caucasian (C) women with stage I versus stage IIIC/IV endometrioid endometrial cancers (EEC). Methods: Tumor DNA was isolated from 80 frozen primary tumors from the GOG-210 protocol. RPCI 19K BAC arrays were hybridized (GeneTAC HybStation) and scanned (Gene Pix 4200AL Laser Scanner). Spot fluorescence values were quantified using ImaGene, vetted for quality and loess corrected with adjustments for chip-specific spatial effects. The genome was segmented to identify regions with common copy number means (DNAcopy software). Posterior aberration probabilities for the regions were obtained using CGHcall and data was visualized and annotated using iGenomicViewer in R. Validation will be performed by fluorescence in situ hybridization using select BAC probes and endometrial cancer tissue microarrays (TMAs) with either 400 cases linked with clinical, treatment and outcome data or 180 AA versus 120 C women from GOG-136. Results: Recurrent CNAs were identified in all stage and race groups. Distinct genomic losses and gains were observed that appear to segregate Caucasian women with stage I disease from African American women with stage I disease and African American or Caucasian women with stage IIIC/IV disease. Conclusions: The GOG-210 bank yielded high quality DNA for detecting and mapping CNAs in frozen primary tumors with high resolution. Our results would imply that racial disparity for AA EEC has a genetic basis regardless of stage. Validation studies are currently underway in two endometrial cancer TMAs. [Table: see text]

No significant financial relationships to disclose.

Laparoscopic management of an obstructed obturator hernia: should laparoscopic assessment be the default option?

An obturator hernia is a rare diagnosis that is frequently missed. Patients present with few clinical signs to identify the cause, apart from symptoms of intestinal obstruction. Therefore, obturator hernias are often diagnosed at exploratory laparotomy. The use of computed tomography (CT) has increased the chance of definitive preoperative diagnosis. However, despite these advances, patients who present acutely will frequently undergo an open procedure rather than laparoscopy. We present a case of an acute obstructed obturator hernia diagnosed in a 62-year-old female that was successfully managed laparoscopically.