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Background Abdominal visceral resections incur relatively higher rates of postoperative bleeding and venous thromboembolism (VTE). While guidelines recommend the use of perioperative chemical thromboprophylaxis, the most appropriate time for its initiation is unknown. Here, we investigated whether early (before skin closure) versus postoperative commencement of chemoprophylaxis affected VTE and bleeding rates following abdominal visceral resection. Methods Retrospective review of all elective abdominal visceral resections undertaken between January 1, 2018, and June 30, 2019, across four tertiary-referral hospitals. Major bleeding was defined as the need for blood transfusion, reintervention, or > 20 g/L fall in hemoglobin from baseline. Clinical VTE was defined as imaging-proven symptomatic disease Results A total of 945 cases were analyzed. Chemoprophylaxis was given early in 265 (28.0%) patients and postoperatively in 680 (72.0%) patients. Mean chemoprophylaxis exposure doses were similar between the two groups. Clinical VTE developed in 14 (1.5%) patients and was unrelated to chemoprophylaxis timing. Postoperative bleeding occurred in 71 (7.5%) patients, with 57 (80.3%) major bleeds, requiring blood transfusion in 48 (67.6%) cases and reintervention in 31 (43.7%) cases. Bleeding extended length-of-stay (median (IQR), 12 (7–27) versus 7 (5–11) days, p p = 0.038) and independently predicted its occurrence. Conclusions The risk of bleeding following elective abdominal visceral resections is substantial and is higher than the risk of clinical VTE. Compared with early chemoprophylaxis, postoperative initiation reduces bleeding risk without an increased risk of clinical VTE.

To determine whether early (before skin closure) versus postoperative chemoprophylaxis affects the incidence of venous thromboembolism (VTE) and bleeding following major abdominal surgery, in a high thromboembolic risk population.Major abdominal surgery incurs both VTE and bleeding risks. Patients with high preoperative VTE risk derive the most benefit from chemoprophylaxis, but carry an increased risk of bleeding. The optimal window for chemoprophylaxis in the perioperative period, whereby both VTE and bleeding risks are minimized, is unknown.Analysis of pooled data from five multicenter studies including only high thromboembolic risk (Caprini score4) patients. Clinical VTE was defined as radiographically-proven symptomatic disease30 days post-surgery. Major bleeding was defined as the need for blood transfusion, reintervention, or20 g/L fall in hemoglobin.From 5501 cases, chemoprophylaxis was initiated early in 1752 (31.8%) patients and postoperatively in 3749 (68.2%) patients. Baseline characteristics were similar between study groups. The incidence of clinical VTE was not associated with chemoprophylaxis timing (early 0.7% vs. postop 0.7%, OR 1.11, 95% CI 0.60-2.15, P=0.730). Contrastingly, compared with postoperative chemoprophylaxis, early usage increased the risk of all bleeding (5.1% vs. 2.6%, OR 2.04, 95% CI 1.52-2.73, P0.001) major bleeding (3.6% vs. 1.8%, OR 1.99, 95% CI 1.40-2.81, P0.001), and reintervention (2.0% vs. 1.0%, OR 2.10, 95% CI 1.32-3.35, P=0.003). Early chemoprophylaxis independently predicted postoperative bleeding (OR 1.71, 95% CI 1.25-2.34, P0.001), but not VTE.In high VTE risk patients undergoing major abdominal surgery, chemoprophylaxis commenced postoperatively reduces bleeding risk without affecting clinical VTE risk.

Major ventral hernia surgeries are commonly performed. Despite guideline recommendations for chemo-thromboprophylaxis in the perioperative period, the optimal timing for its initiation is unknown. We characterized the variability in perioperative chemoprophylaxis in elective major ventral hernia surgery and determine whether timing of chemoprophylaxis affects bleeding and symptomatic venous thromboembolism.Retrospective analysis of all elective major ventral hernia surgery undertaken between January 1, 2014, and December 31, 2019, at 14 hospitals across Australia. Major bleeding was defined as the need for blood transfusion, reoperation, or20 g/L fall in hemoglobin. Clinical venous thromboembolism was defined as imaging-proven symptomatic disease30 days postsurgery. Propensity score matched analysis was used to validate primary findings.In the study, 3,384 hernia repairs were analyzed. Chemoprophylaxis was administered early (before skin closure), postoperatively, or not given in 856 (25.3%), 1,701 (50.3%), and 827 (24.4%) patients, respectively. This varied between surgeons, trainees, and institutions. Clinical venous thromboembolism occurred in 6 (0.2%) patients and was unrelated to chemoprophylaxis timing. 134 (4.0%) patients had postoperative bleeding, with 67 (50%) major bleeds, requiring surgical control in 41 (30.6%) cases. Bleeding extended duration of stay (mean [standard deviation], 7.0 (13.9) vs 2.6 (4.7) days, P.001). Notably, compared with postoperative (odds ratio 1.98; 95% confidence interval, 1.36-2.88; P.001) and no (odds ratio 2.83; 95% confidence interval, 1.70-4.89; P.001) chemoprophylaxis, early initiation significantly increased bleeding risk and independently predicted its occurrence.The incidence of clinical venous thromboembolism after elective major ventral hernia repair is low. Variability in perioperative thromboprophylaxis is high. Early chemoprophylaxis increases bleeding risk without appreciable additional protection from venous thromboembolism.

Background Despite guidelines recommending perioperative thromboprophylaxis for patients undergoing general surgery, we have observed significant variations in its practice. This may compromise patient safety. Here, we quantify the heterogeneity of perioperative thromboprophylaxis across all major general surgical operations, and place them in relation to their risk of bleeding and venous thromboembolism. Methods Retrospective review of all elective major general surgeries performed between 1 January 2018 and 30 June 2019 across seven Victorian hospitals was conducted. Results A total of 5912 patients who underwent 6628 procedures were reviewed. Significant heterogeneity was found in the use of chemoprophylaxis, timing of its initiation, type of anticoagulant administered and application of extended chemoprophylaxis. These variations were observed within the same procedure, and between different surgeries and subspecialties. Contrastingly, there was minimal heterogeneity with the use of mechanical thromboprophylaxis. Oesophago-gastric, liver and colorectal cancer resections had the highest thromboembolic risk. Breast, oesophago-gastric, liver, pancreas and colon cancer resections had the highest bleeding risk. Conclusion Perioperative chemoprophylaxis across general surgery is highly variable. This study has highlighted key areas of variance. Our findings also enable surgeons to compare their practices, and provide baseline data to inform future efforts towards optimizing thromboprophylaxis for general surgical patients.

BACKGROUND Cholecystectomy is commonly performed in general surgery. Despite guidelines recommending chemical thromboprophylaxis in the perioperative period, the most appropriate time for its initiation is unknown. Here, we investigated whether timing of chemoprophylaxis affected venous thromboembolism (VTE) and bleeding rates post-cholecystectomy. METHODS Retrospective review of all elective cholecystectomies performed between 1 January 2018 and 30 June 2019, across seven Victorian hospitals. Clinical VTE was defined as imaging-proven symptomatic disease within 30 days of surgery. Major bleeding was defined as the need for blood transfusion, surgical intervention or >20 g/L fall in haemoglobin from baseline. RESULTS A total of 1744 cases were reviewed. Chemoprophylaxis was given early (pre- or intra-operatively), post-operatively or not given in 847 (48.6%), 573 (32.9%) and 324 (18.6%) patients, respectively. This varied significantly between surgeons, fellows, trainees and institutions. Clinical VTE occurred in 5 (0.3%) patients and was not associated with chemoprophylaxis timing. Bleeding occurred in 42 (2.4%) patients. Of this, half were major events, requiring surgical control in 5 (11.9%) patients and blood transfusion in 9 (21.4%) patients. Bleeding also extended length of stay (mean (SD), 3.1 (4.0) versus 1.4 (2.2) days, P

Urban areas are the primary source of human-made litter globally, and roadsides are a primary accumulation location. This study aimed to investigate how litter arrives at roadsides and determine the accumulation rate and composition of roadside litter. We monitored select roadsides in the Inland Empire, California, for litter abundance (count) and composition (material, item, and brand type). Receipt litter with sale time and location information was used to investigate whether wind, runoff, or human travel were dominant transport agents. Only 9% of the receipts could have experienced runoff, and wind direction was not correlated with receipt transport direction. However, human travel and receipt transport distances were similar in magnitude and distribution, suggesting that the displacement of litter from the place of purchase was predominantly affected by human travel. The median distance receipts traveled from the sale location to the litter observation location was 1.6 km, suggesting that most sources were nearby to where the litter was found. Litter accumulation rates were surprisingly stable (mean 40 349 (33 255–47 865) # km−1yr−1or 1170 (917–1447) kg km−1yr−1) despite repeated cleanups and the COVID-19 stay-at-home orders. A new approach was employed to hierarchically bootstrap litter composition proportions and estimate uncertainties. The most abundant materials were plastic and paper. Food-related items and tobacco products were the most common item types. The identified branded objects were from the primary manufacturers (Philip Morris (4, 2%–7%), Mars Incorporated (2, 1%–3%), RJ Reynolds (2, 1%–3%), and Jack in The Box (1, 1%–3%)), but unbranded objects were prevalent. Therefore, identifiable persistent labeling on all products would benefit future litter-related corporate social responsibility efforts. High-resolution monitoring on roadsides can inform urban litter prevention strategies by elucidating litter source, transport, and accumulation dynamics.

BACKGROUND: Acute biliary pain is the most common presentation of gallstone disease. Untreated patients risk recurrent pain, cholecystitis, obstructive jaundice, pancreatitis and multiple hospital presentations. We examine the outcome of implementing a policy to offer laparoscopic cholecystectomy on index presentation to patients with biliary colic in a tertiary hospital in Australia. METHODS: This is a retrospective cohort study of adult patients presenting to the emergency department (ED) with biliary pain during three 12-month periods. Outcomes in Group A, 3 years prior to policy implementation, were compared with groups 2 and 7 years post implementation (Groups B and C). Primary outcomes were representations to ED, admission rate and time to cholecystectomy. RESULTS: A total of 584 patients presented with biliary colic during the three study periods. Of these, 391 underwent cholecystectomy with three Strasberg Type A bile leaks and no bile duct injuries. The policy increased admission rates (A = 15.8%, B = 62.9%, C = 29.5%, P < 0.001) and surgery on index presentation (A = 12.0%, B = 60.7%, C = 27.4%, P < 0.001). There was a decline in time to cholecystectomy (days) (A = 143, B = 15, C = 31, P < 0.001), post-operative length of stay (days) (A = 3.6, B = 3.2, C = 2.0, P < 0.05) and representation rates to ED (A = 42.1%, B = 7.1%, C = 19.9%, P < 0.001). There was a decline in policy adherence in the later cohort. CONCLUSION: Index hospital admission and cholecystectomy for biliary colic decrease patient representations, time to surgery, post-operative stay and complications of gallstone disease. This study demonstrates the impact of the policy with initial improvement, the dangers of policy attrition and the need for continued reinforcement.

Background Studying proteins and enzymes involved in important biological processes in the Aedes aegypti mosquito is limited by the quantity that can be directly isolated from the mosquito. Adding to this difficulty, digestive enzymes (midgut proteases) involved in metabolizing blood meal proteins require a more oxidizing environment to allow proper folding of disulfide bonds. Therefore, recombinant techniques to express foreign proteins in Escherichia coli prove to be effective in producing milligram quantities of the expressed product. However, with the most commonly used strains having a reducing cytoplasm, soluble expression of recombinant proteases is hampered. Fortunately, new E. coli strains with a more oxidizing cytoplasm are now available to ensure proper folding of disulfide bonds. Results Utilizing an E. coli strain with a more oxidizing cytoplasm (SHuffle® T7, New England Biolabs) and changes in bacterial growth temperature has resulted in the soluble expression of the four most abundantly expressed Ae. aegypti midgut proteases (AaET, AaSPVI, AaSPVII, and AaLT). A previous attempt of solubly expressing the full-length zymogen forms of these proteases with the leader (signal) sequence and a modified pseudo propeptide with a heterologous enterokinase cleavage site led to insoluble recombinant protein expression. In combination with the more oxidizing cytoplasm, and changes in growth temperature, helped improve the solubility of the zymogen (no leader) native propeptide proteases in E. coli. Furthermore, the approach led to autocatalytic activation of the proteases during bacterial expression and observable BApNA activity. Different time-points after bacterial growth induction were tested to determine the time at which the inactive (zymogen) species is observed to transition to the active form. This helped with the purification and isolation of only the inactive zymogen forms using Nickel affinity. Conclusions The difficulty in solubly expressing recombinant proteases in E. coli is caused by the native reducing cytoplasm. However, with bacterial strains with a more oxidizing cytoplasm, recombinant soluble expression can be achieved, but only in concert with changes in bacterial growth temperature. The method described herein should provide a facile starting point to recombinantly expressing Ae. aegypti mosquito proteases or proteins dependent on disulfide bonds utilizing E. coli as a host. Electronic supplementary material The online version of this article (10.1186/s12858-018-0101-0) contains supplementary material, which is available to authorized users.

Acute biliary pain is the most common presentation of gallstone disease. Untreated patients risk recurrent pain, cholecystitis, obstructive jaundice, pancreatitis and multiple hospital presentations. We examine the outcome of implementing a policy to offer laparoscopic cholecystectomy on index presentation to patients with biliary colic in a tertiary hospital in Australia.This is a retrospective cohort study of adult patients presenting to the emergency department (ED) with biliary pain during three 12-month periods. Outcomes in Group A, 3 years prior to policy implementation, were compared with groups 2 and 7 years post implementation (Groups B and C). Primary outcomes were representations to ED, admission rate and time to cholecystectomy.A total of 584 patients presented with biliary colic during the three study periods. Of these, 391 underwent cholecystectomy with three Strasberg Type A bile leaks and no bile duct injuries. The policy increased admission rates (A = 15.8%, B = 62.9%, C = 29.5%, P0.001) and surgery on index presentation (A = 12.0%, B = 60.7%, C = 27.4%, P0.001). There was a decline in time to cholecystectomy (days) (A = 143, B = 15, C = 31, P0.001), post-operative length of stay (days) (A = 3.6, B = 3.2, C = 2.0, P0.05) and representation rates to ED (A = 42.1%, B = 7.1%, C = 19.9%, P0.001). There was a decline in policy adherence in the later cohort.Index hospital admission and cholecystectomy for biliary colic decrease patient representations, time to surgery, post-operative stay and complications of gallstone disease. This study demonstrates the impact of the policy with initial improvement, the dangers of policy attrition and the need for continued reinforcement.

The fatigue life of welded connections can be improved by a variety of post-weld treatment methods. One of the most effective methods is ultrasonic impact treatment (UIT). This technology may be applied during shop fabrication, but the greatest benefit comes from field retrofitting applications. Tensile cyclic stress ranges drive fatigue crack initiation and growth at the weld toe. This is made worse by tensile residual stresses at the weld toe that can reach the yield strength of the base metal resulting from differential cooling of the weld metal during fabrication. This concentration of tensile residual stress can have the effect of fully tensile cyclic stress ranges even in stress reversal zones of the bridge. UIT induces yield-strength level compressive residual stresses by cold forming the material at the weld toe. Prior research has demonstrated the effectiveness of 27 kHz UIT systems for improving the fatigue life of welded bridge girders (Fisher and Roy, 2003). The AASHTO LRFD Bridge Construction Specification Commentary C11.9.1 suggests, but does not explicitly require, the use of 27 kHz systems. The existing language can be interpreted as a prohibition on other UIT systems. This thesis explores the effectiveness of a 20 kHz UIT system applied to transverse stiffener and cover plate termination welds. In this study, fourteen full-scale girders with welded attachments were subjected to constant amplitude fatigue loading. The test matrix considered variables of stress range and minimum stress. Testing has shown that the 20 kHz UIT system provided equivalent effect to the 27 kHz UIT system. The treatment of the transverse stiffener welds improved the performance from Category C’ to at least Category B. The performance of the cover plate termination welds improved from Category E’ to at least Category C. The results demonstrated 20 kHz UIT as a viable option for enhancing the fatigue performance of welded bridge girders. This finding will expand the alternatives available to bridge owners seeking solutions for extending the life of their aging steel bridge inventory. A parametric study was also conducted to investigate the variation of the stress concentration at cover plate terminations with respect to the cover plate and flange geometry. The stress concentration was analyzed using two and three-dimensional finite element analysis conducted with ABAQUS. The analysis indicated that the weld toe stress concentration at Category E’ cover plate details with unusually thick flanges and cover plates was comparable to more typically sized details. The severity of the stress concentration does not increase appreciably if the flange, cover plate, and fillet welds maintain similar proportions to one another. This finding suggests that if those geometric conditions are satisfied, these details would have comparable fatigue resistance as other Category E’ details.

The antibacterial efficacy of 4% chlorhexidine gluconate (CHG) and 1% triclosan as handwash antiseptics is well established. Few published studies have identified hand bacteria found in glove juice samples, and most studies have used nonclinical study subjects. We report a longitudinal comparative study to determine the effect of 4% CHG and 1% triclosan on the composition of the hand bacterial flora of clinical staff in a specialist surgical unit. Prehandwash and posthandwash samples were collected on 3 separate occasions throughout each day by using the glove juice method and a supervised handwashing technique. Total bacterial counts were determined as well as counts for specific pathogens including methicillin-resistant Staphylococcus aureus and coliforms. Both 4% CHG and 1% triclosan were found to effectively reduce the total hand bacterial count preduty (P =.0001). Four percent CHG also was consistently more effective at reducing the total count than was 1% triclosan. However, 1% triclosan eliminated methicillin-resistant S aureus, whereas 4% CHG failed to do so (P =.0001). Gram-negative bacteria were more likely to be eliminated after the use of 4% CHG compared with 1% triclosan. This study is the first to report the effects of 1% triclosan on the bacterial flora present on the hands of clinical staff and demonstrates the ability of 1% triclosan to eliminate methicillin-resistant S aureus.

We investigated the effect of enalaprilat (ET) on long-term preservation of cardiac explant. Isolated rat hearts (n = 7/group) were pretreated with 0 to 40 nM ET and stored at 0 degree C for 16 h. Functional viability was assessed after 30-min working reperfusion without ET. Prestorage control function (mean +/- S.E.M.) (n = 7) included heart rate (HR), 291 +/- 12 bpm; aortic flow (AF). 49.8 +/- 1.9 ml/min; coronary flow (CF), 25.2 +/- 1.3 ml/min; cardiac output (CO), 75.0 +/- 1.2 ml/min; and work, 89.4 +/- 4.7 g-m/min. Post-storage function of untreated hearts was: AF, 61%; CF, 43%; CO, 55%; work, 48% of control. ET (20 nM) enhanced AF recovery to 85%; CF, 58%; CO, 76%; work, 73% of control (P < 0.05 v untreated). Hoe 140 (D-Arg-[Hyp2, Thi5,8, D-Phe7]BK) (1 nM) a bradykinin receptor antagonist, inhibited ET effect; function returned to the untreated level. Protein kinase C (PKC) inhibitors staurosporine (15 nM) and bisindolylmaleimide I (0.5 microM) also blocked ET effect. After 4 h of cold storage, membrane PKC activity changed little from the prestorage level in the untreated hearts, but was elevated significantly from 52.8 +/- 5.2 pmol/min/mg to 74.7 +/- 8.2 by 20 nM ET (P < 0.05 v untreated). Cytosol PKC did not change during 4 h cold storage with or without ET. Neither end-storage nor end-reperfusion myocardial ATP content was affected by 20 nM ET treatment. In conclusion, ET improves cardiac preservation possibly via bradykinin receptor and PKC without affecting ATP metabolism.

Ductal carcinoma in situ (DCIS) is commonly identified on screening mammography. Standard treatment for localized DCIS is wide local excision (WLE) and adjuvant radiotherapy. This approach represents overtreatment in many cases, where the DCIS would never have become clinically significant, or where less intensive treatment would have been satisfactory. We reviewed the medium-term outcome of a cohort of screen detected DCIS patients treated mainly with WLE without radiotherapy.All patients diagnosed with DCIS at NorthWestern BreastScreen between January 1994 and December 2005 were identified from a prospective database. Demographic, pathological, treatment, and outcome data were collected and analyzed. Survival and local recurrence (LR) rates were determined, and associations between various factors and recurrence were analyzed.A total of 422 patients were diagnosed with DCIS. There were 400 patients treated with WLE, and 27 of these received adjuvant radiotherapy. The 5- and 8-year overall and breast cancer specific survival rates were 96.1 and 91.3%, and 99.6 and 99.3%, respectively. The local recurrence rate was 15.4 and 17.1% at 5 and 8 years. Of 56 local recurrences, 34 had WLE after recurrence, 16 of which had adjuvant radiotherapy. No single factor was statistically significantly associated with local recurrence, although combining factors revealed groups where the LR rate was less than 5%.Breast cancer specific mortality was very low in this cohort of older patients with screen-detected DCIS. There was a moderate rate of local recurrence that could usually be salvaged with breast conservation. Decisions regarding adjuvant radiotherapy should take these findings into account.

Australia currently has no system of passive surveillance of antimicrobial resistance in spite of the importance of surveillance in identifying and defining emergent resistance being generally accepted. Queensland Health Pathology and Scientific Services have developed flexible software for passive surveillance with the capacity to handle national data. The system imports raw data strings in delimited ASCII text format into a relational database and screens to exclude duplicates before the processing of the cumulative susceptibility data. It allows considerable flexibility in inquiry parameters and has the ability to 'drill down' to individual laboratory results. Examples of analytical output are given for 49,169 unique isolate results obtained in all Queensland Health Pathology Service laboratories from 1 January to 30 June 2003. The system could form the basis of a national system for passive antimicrobial resistance surveillance.