Geographical Variation in the Use of Diverting Loop Ileostomy in Australia and New Zealand Colorectal Surgeons

David A. Clark,Bree Stephensen,Aleksandra Edmundson,Daniel Steffens,Michael Solomon 대한대장항문학회 2021 Annals of Coloproctolgy Vol.37 No.5

Purpose: Anastomotic leak (AL) after a low pelvic anastomosis is a devastating complication, with short- and long-term morbidity and increased mortality. Surgeons may employ various adjuncts in an attempt to reduce AL rates or mitigate their impact. These include the use of temporary diverting ileostomy (TDI), transanal or rectal tubes and pelvic drains. This questionnaire evaluates the preferences and routine use of these adjuncts in Australasian colorectal surgeons.Methods: A cross-sectional survey was administered to Australian and New Zealand colorectal surgeons on September 20, 2018. The study survey consisted of 15 questions exploring basic demographics and the number of rectal resections and ileal pouches performed in 12 months, along with the surgeon’s preference for the use of diverting stomas, rectal tubes, and pelvic drains.Results: There were 90 respondents to the survey (31.6%). Surgeons in Western Australia (71.4%) were more likely to use a mandatory TDI in colorectal extraperitoneal anastomoses than surgeons in Queensland (14.3%). South Australian surgeons are more likely to employ a mandatory TDI (100%) for ileal pouches than Queensland surgeons (42.9%). Rectal tubes are not commonly utilized (40.0% never use them), and pelvic drains are (45.6% in all cases). Surgeons consider a median AL rate of 15% was felt to justify the use of a TDI in low pelvic anastomoses and a median AL rate of 10% for ileal pouchesConclusion: There is considerable geographical variation in colorectal surgical practice throughout Australia and New Zealand. While surgeons interrogate the same literature, there are presumably other factors that see translation into variations in clinical practice.

A development study of drain fluid gastrografin as a biomarker of anastomotic leak

David A. Clark,Edward Yeoh,Aleksandra Edmundson,Craig Harris,Andrew Stevenson,Daniel Steffens,Michael Solomon 대한대장항문학회 2022 Annals of Coloproctolgy Vol.38 No.2

Purpose: Anastomotic leakage (AL) is the anathema of colorectal surgery. Its occurrence leads to increased morbidity and mortality and a prolonged hospital stay. Much work has gone into studying various biomarkers in drain fluid to facilitate early detection of AL. This stage 2a development study aims to assess the safety and feasibility of reliably detecting the iodine in Gastrografin (GG; Bayer Australia Ltd.) in drain fluid and stool samples by dual-energy computed tomography (DECT). Methods: This is a prospective, observational, controlled, consecutive cohort study establishing the safety and feasibility of the detection of GG in surgical drain fluid and stool as a biomarker of AL when patients with a low pelvic colorectal anastomosis undergo luminal flushing of the rectal tube with GG. Results: Ten consecutive patients were allocated to the saline flush group and the following 10 to the GG flush group. Three patients in the saline flush group developed an AL. One patient in the GG flush group developed an AL. An elevation in the drain fluid GG was detected using DECT on the day of clinical deterioration. None of the patients in the control group were found to have a positive result on DECT. Conclusion: This study demonstrates the safety of a novel approach to the early detection of AL from extraperitoneal colorectal anastomoses. The technique requires validation in a larger cohort and a multicenter study is planned to investigate the efficacy of GG rectal tube flushes as an early biomarker of AL in low pelvic anastomoses.

Cybotactic behavior in the de Vries smectic-A* liquid-crystal structure formed by a silicon-containing molecule.

Ryu, Seong Ho,Shin, Tae Joo,Gong, Tao,Shen, Yongqiang,Korblova, Eva,Shao, Renfan,Walba, David M,Clark, Noel A,Yoon, Dong Ki Published by the American Physical Society through 2014 Physical review. E, Statistical, nonlinear, and so Vol.89 No.3

<P>We have identified a metastable liquid-crystal (LC) structure in the de Vries smectic-A* phase (de Vries Sm-A*) formed by silicon-containing molecules under certain boundary conditions. The phase transition with the metastable structure was observed in a LC droplet placed on a planar aligned substrate and LCs confined in the groove of a silicon microchannel. During the rapid cooling step, a batonnet structure was generated as an intermediate and metastable state prior to the transition that yielded the thermodynamically stable toric focal conic domains. This distinctive behavior was characterized using depolarized reflection light microscopy and grazing incidence x-ray diffraction techniques. We concluded that the silicon groups in the molecules that formed the de Vries phase induced the formation of layered clusters called cybotactic structures. This observation is relevant to an exploration of the physical properties of cybotactic de Vries phases and gives a hint as to their optoelectronic applications.</P>

Channel Gap Measurements of Irradiated Plate Fuel and Comparison with Post-Irradiation Plate Thickness

James A. Smith,Casey J. Jesse,William A. Hanson,Clark L. Scott,David L. Cottle Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

One of the salient nuclear fuel performance parameters for new fuel types under development is changes in fuel thickness. To test the new commercially fabricated U-10Mo monolithic plate-type fuel, an irradiation experiment was designed that consisted of multiple mini-plate capsules distributed within the Advanced Test Reactor (ATR) core, the mini-plate 1 (MP-1) experiment. Each capsule contains eight mini-plates that were either fueled or "dummy" plates. Fuel thickness changes within a fuel assembly can be characterized by measuring the gaps between the plates ultrasonically. The channel gap probe (CGP) system is designed to measure the gaps between the plates and will provide information that supports qualification of U-10Mo monolithic fuel. This study will discuss the design and the results from the use of a custom-designed CGP system for characterizing the gaps between mini-plates within the MP-1 capsules. To ensure accurate and repeatable data, acceptance and calibration procedures have been developed. Unfortunately, there is no "gold" standard measurement to compare to CGP measurements. An effort was made to use plate thickness obtained from post-irradiation measurements to derive channel gap estimates for comparison with the CGP characterization.

Highly Oriented Liquid Crystal Semiconductor for Organic Field-Effect Transistors

Han, Moon Jong,Wei, Dayan,Kim, Yun Ho,Ahn, Hyungju,Shin, Tae Joo,Clark, Noel A.,Walba, David M.,Yoon, Dong Ki American Chemical Society 2018 ACS central science Vol.4 No.11

<▼1><P/><P>We report a mesogenic compound which introduces nematic liquid crystal (LC) ordering into the benzothienobenzothiophene (BTBT) family of LCs, creating a new class of LC semiconducting materials which respond in a facile way to anisotropic surfaces, and can, thereby, be effectively processed into highly oriented monodomains. Measurement on these domains of the electrical conductivity, with in situ monitoring of domain quality and orientation using LC birefringence textures in electroded cells, brings a new era of precision and reliability to the determination of anisotropic carrier mobility in LC semiconductors.</P></▼1><▼2><P>The synthetic LC OSC is uniaxial planar aligned on the rubbed polymer substrate due to the long-range ordering characteristic of the nematic phase directly observed by polarized optical microscopy.</P></▼2>

Nucleation and growth of a helical nanofilament (B4) liquid-crystal phase confined in nanobowls

Ryu, Seong Ho,Kim, Hanim,Lee, Sunhee,Cha, Yun Jeong,Shin, Tae Joo,Ahn, Hyungju,Korblova, Eva,Walba, David M.,Clark, Noel A.,Lee, Sang Bok,Yoon, Dong Ki The Royal Society of Chemistry 2015 SOFT MATTER Vol.11 No.39

<P>The B4 helical nanofilament (HNF) liquid crystal (LC) phase is a three-dimensional (3D) helical structure composed of 2D smectic layers. Because of the complex shape of the HNF phase, it is difficult to understand the generation mechanism of HNFs in the bulk as well as in the thin-film condition. Here, we directly investigated the nucleation and growth of HNFs in nanobowls. A combination of electron microscopy and X-ray diffraction was used to reveal the transitional surface structures, in which barrel-like structures as well as short HNFs with random handedness were observed, depending on the LC film thickness. These results will be useful in achieving a better understanding of thin film structures of complex chiral structures in soft matter.</P> <P>Graphic Abstract</P><P>We investigated the confined B4, helical nanofilament LC phase in nanobowls as a function of LC film thickness. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5sm01783a'> </P>

Self-assembled hydrophobic surface generated from a helical nanofilament (B4) liquid crystal phase

Kim, Hanim,Yi, Youngwoo,Chen, Dong,Korblova, Eva,Walba, David M.,Clark, Noel A.,Yoon, Dong Ki The Royal Society of Chemistry 2013 Soft matter Vol.9 No.10

<P>Hydrophobic air/liquid crystal (LC) surfaces exhibiting self-assembled dual scale roughness have been made by simple cooling of a bent-core mesogen from its high temperature isotropic melt through two liquid crystal phases. The transition to the fluid smectic B2 phase generates micron-scale toric focal conic domains (TFCDs) at the surface. Upon further cooling into the hexatic smectic B4 phase these TFCD structures are preserved and become textured by the nanometer-sized helical nanofilaments (HNFs) of the B4. The resulting TFCD/HNF surface is hydrophobic and shows clear evidence for surface tension reduction characteristic of dual-scale roughness, suggesting a simple self-assembly-based approach to low surface tension surfaces using LC morphology.</P> <P>Graphic Abstract</P><P>Hydrophobic air/liquid crystal (LC) surfaces exhibiting self-assembled dual scale roughness have been made by simple cooling of a bent-core mesogen from its high temperature isotropic melt through two liquid crystal phases. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3sm27221d'> </P>

Discovery Elbow System arthroplasty polyethylene bearing exchange: outcomes and experience

Daniel L J Morris,Katherine Walstow,Lisa Pitt,Marie Morgan,Amol A Tambe,David I Clark,Timothy Cresswell,Marius P Espag 대한견주관절학회 2024 대한견주관절의학회지 Vol.27 No.1

Background: The Discovery Elbow System (DES) utilizes a polyethylene bearing within the ulnar component. An exchange bearing requires preoperative freezing and implantation within 2 minutes of freezer removal to allow insertion. We report our outcomes and experience using this technique. Methods: This was an analysis of a two-surgeon consecutive series of DES bearing exchange. Inclusion criteria included patients in which exchange was attempted with a minimum 1-year follow-up. Clinical and radiographic review was performed 1, 2, 3, 5, 8 and 10 years postoperative. Outcome measures included range of movement, Oxford Elbow Score (OES), Mayo Elbow Performance Score (MEPS), complications and requirement for revision surgery. Results: Eleven DESs in 10 patients were included. Indications were bearing wear encountered during humeral component revision (n=5); bearing failure (n=4); and infection treated with debridement, antibiotics and implant retention (DAIR; n=2). Bearing exchange was conducted on the first attempt in 10 cases. One case required a second attempt. One patient developed infection postoperatively managed with two-stage revision. Mean follow-up of the bearing exchange DES was 3 years. No further surgery was required, with no infection recurrence in DAIR cases. Mean elbow flexion-extension and pronosupination arcs were 107° (±22°) and 140° (±26°). Mean OES was 36/48 (±12) and MEPS was 83/100 (±19). Conclusions: Our results support the use of DES bearing exchange in cases of bearing wear with well-fixed stems or acute infection. This series provides surgeons managing DES arthroplasty with management principles, successful and reproducible surgical techniques and expected clinical outcomes in performing DES polyethylene bearing exchange. Level of evidence: IV.

Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: An Australian Institution’s Experience

Ming Han Lim,Anton R. Lord,Lisa A. Simms,Katherine Hanigan,Aleksandra Edmundson,Matthew J.F.X. Rickard,Russell Stitz,David A. Clark,Graham L. Radford-Smith 대한대장항문학회 2021 Annals of Coloproctolgy Vol.37 No.5

Purpose: We report outcomes and evaluate patient factors and the impact of surgical evolution on outcomes in consecutive ulcerative colitis patients who had restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) at an Australian institution over 26 years.Methods: Data including clinical characteristics, preoperative medical therapy, and surgical outcomes were collected. We divided eligible patients into 3 period arms (period 1, 1990 to 1999; period 2, 2000 to 2009; period 3, 2010 to 2016). Outcomes of interest were IPAA leak and pouch failure.Results: A total of 212 patients were included. Median follow-up was 50 (interquartile range, 17 to 120) months. Rates of early and late complications were 34.9% and 52.0%, respectively. Early complications included wound infection (9.4%), pelvic sepsis (8.0%), and small bowel obstruction (6.6%) while late complications included small bowel obstruction (18.9%), anal stenosis (16.8%), and pouch fistula (13.3%). Overall, IPAA leak rate was 6.1% and pouch failure rate was 4.8%. Eighty-three patients (42.3%) experienced pouchitis. Over time, we observed an increase in patient exposure to thiopurine (P=0.0025), cyclosporin (P=0.0002), and anti-tumor necrosis factor (P<0.00001) coupled with a shift to laparoscopic technique (P<0.00001), stapled IPAA (P<0.00001), J pouch configuration (P<0.00001), a modified 2-stage procedure (P=0.00012), and a decline in defunctioning ileostomy rate at time of IPAA (P=0.00002). Apart from pouchitis, there was no significant difference in surgical and chronic inflammatory pouch outcomes with time.Conclusion: Despite greater patient exposure to immunomodulatory and biologic therapy before surgery coupled with a significant change in surgical techniques, surgical and chronic inflammatory pouch outcome rates have remained stable.

Multistep hierarchical self-assembly of chiral nanopore arrays

Kim, Hanim,Lee, Sunhee,Shin, Tae Joo,Korblova, Eva,Walba, David M.,Clark, Noel A.,Lee, Sang Bok,Yoon, Dong Ki National Academy of Sciences 2014 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.111 No.40

<P><B>Significance</B></P><P>Bent-core mesogenic molecules form smectic liquid crystal phases in which the molecular layers are locally polar and chiral, and have a built-in tendency for saddle splay curvature, a combination that fills bulk neat bent-core smectics with self-assembled helical nanofilament bundles of twisted layers. This observation led us to explore the growth mode of such smectics under conditions of nanoconfinement and the remarkable observation reported here that single nanofilaments readily grow in linear nanoscale pores, generating a new motif of hierarchically self-assembled hybrid organic/inorganic structures for applications in chiral synthesis and separation.</P><P>A series of simple hierarchical self-assembly steps achieve self-organization from the centimeter to the subnanometer-length scales in the form of square-centimeter arrays of linear nanopores, each one having a single chiral helical nanofilament of large internal surface area and interfacial interactions based on chiral crystalline molecular arrangements.</P>